JP2000047118A - Endoscopic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscopic device by which the observation is smoothly executed and also whose durability is improved. SOLUTION: A zoom lens mounted in the objective optical system at the leading end part of the endoscope is connected to an actuator 39, and the zoom lens is moved in the optical axis direction in accordance with the movement of the actuator 39. When a zoom switch is turned on, waveform data is read from a ROM 66 through an energizing control circuit 71 and an FPGA 65, and a driving signal is applied on the actuator 39 through an amplification circuit 68 etc., and a current at this time is detected by a current detection circuit 72, and integrated, then, compared with the limit value of a limit value setting circuit 76 by a comparison circuit 75, and in the case that the value is exceeding the limit value, by energizing while reducing the driving pulse ratio, the function of the smooth endoscopic observation is secured while maintaining the zooming operation, and also, by limiting the energizing quantity, the actuator 39 is restrained from being heated, then, the durability is secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope apparatus for driving a driven body such as a zoom lens by a piezoelectric actuator.

[0002]

2. Description of the Related Art In recent years, endoscopes have been widely used in the medical and industrial fields. For example, JP-A-9-
In the endoscope apparatus disclosed in Japanese Patent No. 988583, a part of the objective optical system is constituted by a zoom lens, and the zoom lens is connected to a moving object moved by a piezoelectric actuator to move the zoom lens. Which changes the magnification of the observation image by using the above method. In the endoscope apparatus having such a configuration, routine inspection and close observation can be performed by changing the magnification with one endoscope, which is convenient.

[0003]

When an objective optical system constituting a zoom lens of an endoscope is driven by using the above-described piezoelectric actuator, if the zoom operation is performed continuously for a long time or frequently, this actuator is required. When current is supplied to the piezoelectric element, heat is generated in the piezoelectric element, and there is a disadvantage that the characteristics of the element are deteriorated, and the element is easily burnt or broken.

On the other hand, in the above-mentioned publication, when the current flowing through the actuator exceeds a predetermined threshold value, the overcurrent protection circuit determines that the current is an overcurrent and stops the energization of the actuator to protect the actuator. I have.

However, in this configuration, when the zoom operation is performed at a high frequency, the zoom operation is stopped every time the current amount exceeds the threshold value, and it is necessary to wait for a while until the zoom operation can be performed normally. As a result, smooth endoscopy was not possible, and the usability was poor.

(Object of the Invention) The present invention has been made in view of the above-mentioned points, and has as its object to provide an endoscope apparatus which enables smooth endoscope observation and has excellent durability. I have.

[0007]

SUMMARY OF THE INVENTION An endoscope having a driven body driven by a piezoelectric actuator, a control device detachably connected to the endoscope to drive and control the piezoelectric actuator, In an endoscope device including a switch that generates a drive signal, in the control device, a current limit detecting unit that detects a current limit to the piezoelectric actuator, and a predetermined limit value related to the current limit, A comparison unit configured to compare a magnitude of the detection value detected by the current detection unit with the limit value; and an energization control unit configured to variably control an energization amount to the piezoelectric actuator based on a comparison result by the comparison unit. By providing a function of driving the driven body by reducing the amount of energization even if the detection value exceeds the limit value,
Smooth endoscope observation is ensured, and heat generation is suppressed due to a decrease in the amount of electricity, thereby preventing a decrease in durability.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 15 show a first embodiment of the present invention.
FIG. 1 shows an appearance of an endoscope apparatus according to a first embodiment of the present invention, and FIG. 2 shows an entire configuration of the endoscope apparatus according to the first embodiment. 3 shows the appearance of the endoscope, FIG. 4 shows the structure of the distal end of the endoscope, FIG. 5 shows the appearance of the actuator provided at the distal end, FIG. 6 shows the structure of the actuator, and FIG. 8 shows a waveform of a drive signal, FIG. 8 shows a front view of the zoom control device, FIG. 9 shows a display example of a monitor screen, FIG. 10 shows a schematic configuration of the zoom control device, and FIG. FIG. 12 shows the operation when the zoom switch is turned on, FIG. 13 shows the drive pulse ratio, and FIG. 14 shows the waveform of the current detected by the current detection circuit and the integrated value of the current. ,
FIG. 15 shows the magnitude relation of the current integrated value including the limit value set by the limit value setting circuit.

The endoscope apparatus 1 according to the first embodiment of the present invention shown in FIGS. 1 and 2 has a zoom function (adjustable to any magnification from magnification to wide angle). Hereinafter, the light source device 3 supplies illumination light to a light guide of the endoscope 2, a camera control unit (abbreviated as CCU) 4 that performs signal processing on image pickup means, and the like. , A color monitor 5 for displaying a video signal output from the CCU 4, a zoom control device 6 for performing enlargement / wide-angle control (also simply referred to as zoom control), and a foot switch 7 detachably connected to the zoom control device 6. And

As shown in FIG. 3, the endoscope 2 includes an elongated insertion portion 8 inserted into a patient's body, etc., an operation portion 9 provided at a base end of the insertion portion 8, and an operation portion 9. A universal cord 11 having one end extended, and a connector 12 provided at the other end of the universal cord 11 (see FIG. 1)
Is detachably connected to the light source device 3.

The insertion portion 8 has a hard distal portion 13 in which the image pickup means is built, a bendable portion 14 provided at the rear end of the distal portion 13, and a flexible portion 14 provided at the rear end of the curved portion 14. By operating a bending operation knob 16 provided on the operation section 9, the bending section 14 is formed of a flexible tube section 15 having flexibility.
Can be curved.

As shown in FIG. 1, a connector 18 at one end of a video cable 17 is connected to the connector 12, and a connector 19 at the other end of the video cable 17 is detachably connected to the CCU 4.

A zoom cable 20 is connected to the connector 12.
Is connected detachably, a zoom connector 21 at the other end of the zoom cable 20 is connected to one end of a connection cable 23 via a connection connector 22, and a connector 24 at the other end of the connection cable 23 is It is detachably connected to the zoom control device 6. The zoom connector 21 has a waterproof structure by attaching a waterproof cap 25 for the zoom connector, and can perform washing and the like.

The zoom cable 20 has no connection connector 22 and no zoom connector 21,
It may be an integral type that doubles as 3. In this case, the connector 24 is replaced with the zoom connector 21.

The zoom cable 20 is connected to the connector 1
2 is detachably connected to the connector 20a.
2. The structure is easily detached from the device 2 with a weak force (for example, there is no lock mechanism for maintaining the connection state).

By adopting such a structure, even when a user accidentally hooks a part of the body on the zoom cable 20 at the time of an inspection or the like, the connector 20a is disengaged from the connector 12 by a weak force at the time of hooking. The detachment prevents disconnection of the zoom cable 20 and the like, and prevents breakage of connector contacts and the like.

Further, two types of zoom cables 20 having different cable lengths are provided as the zoom cable 20, and an appropriate cable length is set according to the position or distance between the zoom control device 6 and the connector 12 of the endoscope 2. That can be used. Note that the cable length is not limited to two types and may be three or more types. Instead of preparing a plurality of zoom cables 20 having different lengths, the zoom cable 20 may be made curl-cord-type so that it can be extended and contracted.

A foot switch connector 27 provided at the other end of a connection cord 26 having one end connected to the foot switch 7 as a remote switch is detachably connected to the zoom control device 6. The foot switch 7 is provided with an enlargement operation foot switch 7a and a wide angle operation foot switch 7b. As shown in FIG. 3, the foot switch 7 is provided with an enlarged operation foot switch 7a and a wide angle operation foot switch 7b on the slope so that the foot switch 7 can be easily operated by stepping on the foot. For example, an inclined plate is attached to the bottom surface of the foot switch 7 with a screw or the like, or is integrally attached with an adhesive or the like.

As shown in FIG. 2, a light guide fiber 31 is inserted into the endoscope 2 and the connector 12 is connected to the light source device 3 so that the illumination light from the lamp 32 in the light source device 3 is transmitted to the light guide. The illumination light is incident on one incident end of the fiber 31, and this illumination light is transmitted, emitted from the other end fixed to the distal end portion 13 of the insertion section 8 through the illumination lens 33, and illuminates a subject such as an affected part.

As shown in FIGS. 2 and 4, the distal end portion 13 of the endoscope 2 has an objective optical system 34 as a zoom optical system.
In the vicinity of the image forming position of the objective optical system 34, an imaging device for capturing an observation image passing through the objective optical system 34, preferably a solid-state imaging device, more specifically, a charge-coupled device (abbreviated as CCD) 3
5 is built-in.

The objective optical system 34 is provided with a zoom lens 38 movable in the direction of the optical axis, and the movement of the zoom lens 38 enables wide angle / magnification (adjustment of magnification ratio). In FIG. 4, each lens of the objective optical system 34 is shown in a half section. An actuator 39 for driving a zoom lens 38 as a driven body is provided in the distal end portion 13 and is connected to the zoom lens 38. The zoom lens 38 is moved in the optical axis direction by driving the actuator 39.

As shown in FIGS. 5 and 6, the actuator 39 is a so-called impact type piezoelectric actuator (rapidly deformable actuator),
1, a moving body 42 provided so as to be able to move inside the pipe 41 in the axial direction, and a notch 43 provided on the side of the pipe 41 so as to be engaged with the moving body 42. A friction plate 44 is provided on the inner surface as a frictional force generating mechanism for pressing the shaft in a direction perpendicular to the axis. The friction plate 44
The moving member 42 is moved by pressing against the friction plate 44 by being formed of an elastically deformable plate member bent in a triangular mountain shape.

A fitting hole 45 is formed in the side of the tip of the moving body 42.
The output shaft attached to the zoom lens 38 is fitted into and fixed to the fitting hole 45. A guide 46 having a shape in which the pipe is cut in half is provided on the distal end side of the pipe 41 in order to hold the distal end of the moving body 42.

The moving body 42 has a sliding pipe 47 whose outer surface comes into contact with and slides against the inner surface of the pipe 41, an upper lid 48 and a lower lid 49 provided at both openings of the sliding pipe 47, and
A piezoelectric element 50 is provided inside the sliding pipe 47 and has a lower lid 49 having one end firmly fixed to one end thereof.
The piezoelectric element 50 is connected with a lead wire 51 for supplying drive power to the piezoelectric element 50, and this lead wire 51 is connected to the endoscope 2.
1, and is electrically connected to the zoom control device 6 via the zoom cable 20 when the endoscope 2 is connected as shown in FIG.

The piezoelectric element 50 is formed by laminating ceramic piezoelectric members such as barium titanate, lead zirconate titanate, and porcelain, and providing electrodes thereon. When a force that moves the moving body 42 with a force smaller than the frictional force caused by the pressure contact of the friction plate 44 is applied, the movement of the moving body 42 is suppressed, and the moving body 42 is moved with a force larger than the frictional force. When the moving force acts, the moving body 42 moves overcoming the frictional force. In the present embodiment, an impact type piezoelectric actuator that applies a drive signal having a sharply changing waveform to the actuator 39 in order to generate a force larger than the frictional force is employed.

As shown in FIG. 1, the drive section 52 in the zoom control device 6 generates a drive signal having the waveform shown in FIG. 7, and the piezoelectric element 50 is driven in the direction parallel to the optical axis in FIG. Mechanically expands or contracts.

More specifically, the driving section 51 is provided as shown in FIG.
As shown in (1), a waveform obtained by rectifying a sine wave into a full wave (in this case, it is also driven in the T direction, so it is also called a T-direction drive waveform)
7B, and a drive signal having a waveform obtained by inverting the drive signal of FIG. 7A (in this case, the drive signal is driven in the W direction and is also referred to as a W direction drive waveform). Is output. In FIG. 7, the horizontal axis represents time, and the vertical axis represents the voltage of the drive signal. Each drive signal has an amplitude of 90 V, for example. These waveforms include a waveform portion that expands or contracts the piezoelectric element 50 slowly over time, and a waveform portion that expands or contracts sharply.

For example, when the drive signal shown in FIG. 7A is applied to the piezoelectric element 50, the time-differential waveform of the voltage is discontinuously inverted (in this case, the direction in which the piezoelectric element 50 contracts rapidly from the contracting direction). 4), the moving body 42 moves to the right in FIG. 4, for example, about several microns per one cycle of the drive signal.

The movement of the moving body 42 also moves the zoom lens 38 to the right, and in this case, the objective optical system 34
Is in a lens state that is larger than before the movement.

On the other hand, the drive signal shown in FIG.
When the voltage is applied to 0, the moving body 42 is moved to the left in FIG.
Also moves to the left, and in this case, the objective optical system 34 enters a lens state in which the angle becomes wider than before the movement.

The zoom lens 38 constituting the objective optical system 34 is different from a general so-called zoom lens (the focus point does not change even if the magnification is changed). ). When the magnification is changed, for example, the depth of field is 5 to 100 m on the wide-angle side.
m, the depth of field changes from 2 to 5 mm on the magnification side.

In this embodiment, basically, a minute distance is moved by one cycle Tc or Tc 'of the drive signal shown in FIG. 7A or 7B, and the drive is performed in one cycle of this drive signal. Since a predetermined distance or the like is moved by controlling the number of signals, a drive pulse is used instead of a drive signal, or the number of drive signals is abbreviated as the number of drive pulses.

As will be described later, in the step mode or the like, the time Ta or Ta 'during which the drive signal is actually output can be selected within the time Tb or Tb' shown in FIG. That is, by selecting the drive pulse ratio as shown in FIG. 7, the user can change the moving speed of the zoom lens 38.

As shown in FIG. 2, an image signal picked up by the CCD 35 is amplified by a preamplifier 36, and then amplified by a CCU.
4, a standard video signal is generated, and this video signal is input to the color monitor 5 via a monitor cable, and an image of the subject is displayed on the monitor screen.

The operation unit 9 is provided with a zoom switch 40 for operating the actuator near the bending knob 16. Then, an operation signal when the zoom switch 40 or the foot switch 7 is operated is input to a control circuit 53 provided in the zoom control device 6.

That is, the zoom switch 40 and the foot switch 7 form a remote switch connected to the zoom control device 6 by a cable or the like and provided at a separated position.

The zoom switch 40 is connected to the enlargement side (Te
(Le side and below, T direction) switch 40T and wide angle side (Wi
(de direction, W direction) switch 40W. For example, when the zoom switch 40 is tilted forward, the T-direction switch 40T is turned on, and when it is tilted rearward, the W-direction switch 40W is turned on. Note that the zoom switch 40 may have a structure that can be set in two steps in each of the T direction and the W direction.

As shown in FIG. 3, the operating section 9 has a curved knob 1
6. A zoom switch 40 for operating the actuator is provided near 6.
An air supply / water supply button 10a for performing an air supply / water supply operation and a suction button 10b for performing a suction operation are provided near the bending knob 16. The zoom control device 6 is provided with a detecting means for detecting the connection of the connector 27 of the foot switch 7. When the connector 27 is connected, the foot switch 7 is given priority and the zoom switch 40 is operated. In this case, the control circuit 53 does not accept the zoom operation.

Thus, when the foot switch 7 is connected, the zoom operation is preferentially performed with this, and when the bending knob 16 is operated to bend, it is erroneously provided near the bending knob 16. Even if the user touches or moves the zoom switch 40, the zoom operation is not performed.

As shown in FIG. 8, a power switch 56 and a connector receiver 57 to which the connector 24 is detachably connected are provided on the front of the zoom controller 6, and a front side for setting a mode or the like is provided above these. A panel 58 is provided.

The front panel 58 includes a step mode switch 59 for setting operation of the actuator 39 (or the zoom lens 38) in a step mode in which the actuator 39 (or the zoom lens 38) is stepped by a predetermined amount when the remote switch is pressed once. A speed mode switch (or a continuous movement mode switch) 60 is provided for continuously moving only when the button is pressed.

In the step mode and the speed mode, switches 49a to 49e and 50a to 50e for setting the moving amount or moving speed in a plurality of stages are provided (in FIG. 8, for simplicity, the sign switches 49a, 4a).
9e, 50a and 50e only). These switches 4
Each of 9a to 49e and 50a to 50e has a switch function for selecting and an indicator function for indicating that the switch is selected.

For example, when the speed mode switch 60 is pressed in order to switch from the step mode to the speed mode, for example, the switch 60c of level 3 is set to the selected speed mode in the initial setting state,
The switch 60c is illuminated (by an indicator such as an internal LED) so that the operator can recognize it.

In the speed mode, the remote switch is set to 1
The number of signals for which a drive signal is output within a certain time Tb when the button is pressed once can be set in five stages by switches 60a to 60e. That is, a desired drive pulse ratio shown in FIG. 7A can be selected from five stages.

For example, in FIG.
0a has the smallest number of signals, and the switch 60e of (level) 5 is set in a stepwise manner so that the number of signals is largest. The switch 60c of (level) 3 has an intermediate number of signals, and is normally set to a value at which the moving operation can be sufficiently performed with this setting.

A similar function is provided in the step mode. In this step mode, the time during which the drive signal is output when the remote switch is pressed once can be set in five stages by the switches 59a to 59e. For example, in FIG. 8, the switch 59a of (level) 1 is set in a stepwise manner so that the time during which the drive signal is output is the shortest, and the switch 59e of (level) 5 is the longest. Then, the switch 59c of (level) 3 is an intermediate time, and is usually set to a value at which the moving operation can be sufficiently performed by this setting.

The front panel 58 shown in FIG. 8 has, for example, an LED 61A in the vicinity of a portion described as being operated at low speed.
Is provided, and the control circuit 53 turns on the LED 61A to notify the user that the vehicle is running at a low speed when the energization amount described below is being limited.

The control circuit 53 sends a signal to the video signal processing circuit 37 shown in FIG.
As shown in (1), a display 61B is displayed on the monitor screen, which is an operation state during the limitation of the power supply amount such as SLOW. The user may be notified or notified that the power supply amount is being limited by displaying only one of FIG. 8 and FIG. In addition, the user may be notified or notified by a buzzer sound or the like that the power supply amount is being limited.

FIG. 10 shows a functional configuration inside the zoom control device 6. Foot switch 7, zoom switch 40
When the mode switch 59 of the front panel 58 is operated, the respective signals are input to the CPU 63 via the I / O port 62.

The CPU 63 is connected to a RAM 64 used to store mode selection information and the like and to be used as a work area where the CPU 63 processes according to a program. The CPU 63 is connected to a field programmable gate array (abbreviated as FPGA) 65, receives an operation signal from a remote switch, sends a signal according to the instruction to the FPGA 65, and sends an address signal generated by the FPGA 65 to the FPGA 65. The drive waveform data of the drive signal is applied to the ROM 66 in which the drive signal has been written in advance, and the corresponding drive waveform data is read.

The drive waveform data read from the ROM 66 is converted into an analog drive waveform signal by the D / A converter 67, and the amplifier circuit 68 constituting the drive unit 51
The driving signal is amplified by the controller 39 and is applied to the actuator 39. Further, in the present embodiment, there is provided a current detection and integration means 69 for detecting and integrating a current flowing through the actuator 39, and the output of the current detection and integration means 69 is input to the CPU 63, and the CPU 63
It is characterized in that the amount of current supply (the amount of injected current) is variably controlled as compared with the limit value in 63.

FIG. 11 shows a more specific configuration of FIG. When the remote switch is operated, the energization control circuit 71 constituted by the CPU 63 issues a corresponding signal generation command to F
Put out to PGA65. In this case, a signal generation command for driving at the drive pulse ratio n / N stored in the RAM 64 in the initially set state is issued.

The FPGA 55 receives this signal, applies an address signal to the ROM 66, reads out the previously written drive waveform data, and sends it to the D / A converter 67.

The D / A converter 67 converts the signal into an analog signal and outputs the signal to an amplifier circuit 68 constituting the drive unit 51.
The drive signal is amplified by the amplifier circuit 68 and output to the actuator 39.

The current value of the drive signal flowing through the actuator 39 is detected by a current detection circuit 72, and is converted into a digital signal by an A / D converter 73.
4 and integration is performed. The integrated current area is compared with the limit value setting circuit 7 by the comparison circuit 75 by the CPU 63.
6 is compared to the limit value.

When the value is equal to or less than the limit value, the operation of the power supply control circuit 71 is continued.
Referring to the drive pulse ratio of the drive pulse ratio setting circuit 77 constituted by M64 (instead of stopping the energization)
The amount of current is variably limited.

Next, the operation of operating the zoom switch 40 to control the amount of energization will be described below with reference to FIG. When a remote switch such as the zoom switch 40 is operated, the CPU 63 performs a signal generation command process as shown in step S1.

That is, this signal generation command is transmitted to the FPGA 65
The FPGA 65 performs a process of specifying an address to a ROM 66, and the waveform data read from the ROM 66 passes through a D / A converter 67 and is further amplified by an amplifying circuit 68.
And is output to the actuator 39.

That is, the drive pulse energizing process in step S2 starts. In this case, the drive pulse ratio n / N is more specifically nin / 400, and this value is an initially set value.

FIG. 13 shows a drive pulse waveform read out from the ROM 66 and output, and shows a drive pulse ratio n / N in this case.

The basic cycle (N in number of pulses) of the intermittent energizing pulse is set to a time corresponding to 400 pulses.
In this case, the frequency is set to about 20 kHz. This is a pulse amount that allows the endoscope image at the time of zooming to be captured by the naked eye as a smooth movement.

Next, as shown in step S3, the drive signal flowing through the actuator 39 is subjected to current detection and integral calculation to calculate the area S. The current waveform applied to the actuator 39 and detected by the current detection circuit 72 is a waveform having positive and negative polarities such as a sine wave distorted as shown in FIG.

Then, detection (rectification) of the current detection circuit 72 is performed.
14A is extracted, and the positive portion shown by the diagonal lines in FIG. 14A is extracted.
As shown in (B), the average area S = (S1 + S2 + S3)
+ ... Sn) / n is calculated.

Then, it is determined whether or not the area S calculated in the next step S4 is larger than the area Sth of the limit value.

That is, it is determined whether or not the area S is larger than the area Sth (of the limit value) in the heat-generating temperature state that causes deterioration in the characteristics and the life of the piezoelectric element 50.

FIG. 15 shows the relationship between the current integral (integrated) values. In a normal use state, the area Snor in that case is smaller than the area (value) Sth of the limit value, and the value of the area increases as the temperature increases due to heat generation, and becomes maximum as shown in Sshort in a short-circuit state. . In the released state, the value is 0. In FIG. 15, the value Sshor in the short-circuit state is shown.
threshold values Ssh and Sop for detecting the values of t and the released state
Are also shown.

Then, according to the judgment in step S4,
When the detected area S is larger than the area Sth of the limit value, the process of changing the pulse ratio setting is performed as shown in step S5. That is, n in the pulse ratio n / 400
Is reduced to n-1 (may be reduced to 2 or 3 instead of 1).

Further, the CPU 63 outputs to the video signal processing circuit 37 that the power supply amount is to be restricted, and causes the display screen of the monitor 5 to display a display 61B as shown in FIG. LED 61A indicates that the vehicle is running at low speed. From these displays, the user can recognize that the use state is limited in the amount of power supply, and can recognize that even if the zoom speed is slower than the normal use state, it is not due to a failure or the like.

Next, it is determined whether or not n <4 in step S6. That is, it is determined whether or not the current pulse ratio n / 400 is equal to or smaller than the minimum value at which zooming can be stably performed in a desired direction. If n.ltoreq.4, it is difficult to perform the moving operation stably. If the value is less than this value, the CPU 63 issues an energization stop command in step S7 to stop energization in step S8. When the power supply is stopped, the user may be notified that the power supply has been stopped by a buzzer or the like.

If n <4 in step S6 is not satisfied, the process returns to step S1. In step S4, S> S
If it does not correspond to th, then n <nin in step S9
Is determined.

That is, it is determined whether or not the current pulse ratio n / N is smaller than the initially set pulse ratio nin / N. If not, the process returns to step S1. Performs the process of changing the pulse ratio setting in step S10. That is, n in the pulse ratio n / 400 is increased to n + 1, and the process returns to step S1 (may be increased by 2 or 3 instead of 1). In this case, since the temperature of the actuator 39 is equal to or lower than the limit value,
Increase the pulse ratio and return to the ratio at the time of initial setting.

By performing such a process of controlling the amount of energization, a remote switch such as the zoom switch 40 is temporarily operated frequently, and the actuator 39 (the piezoelectric element 5 of the actuator 39) is operated.
When the temperature of 0) is equal to or higher than the limit value, the amount of power is reduced to maintain the zoom function.
A smoother endoscope inspection function can be ensured than in the case of stopping.

In this case, the zoom function is lower than the normal zoom function. However, since this state is displayed to the user on the monitor 5 or the like (presentation), the user is notified.
The user can recognize the state.

When the temperature of the actuator 39 (the piezoelectric element 50 thereof) exceeds the limit value,
Since the amount of energization is reduced, the rise in temperature can be effectively suppressed, and characteristic durability of the actuator 39 can be prevented to ensure excellent durability.

The amount of decrease in the energizing pulse ratio may be varied according to the difference between the current integral value and the limit value.

FIG. 16 is a flowchart of a zoom control operation having a function of controlling the amount of power supply according to a modification.

This modification is different from the one in step S4 in FIG.
> Instead of making a determination of Sth, S> of step S4 '
The judgment of Snori (i = 1 to 5) is made, and if it does not correspond to this, the process of step S10 is performed.

FIG. 17 shows the drive pulse ratio initial setting values nin1 to nin5 for the levels 1 to 5 in the speed mode of FIG. 8 and the current integrated values Snor1 to Snor5 in the normal (normal) state.

That is, in step S4 'of FIG. 16, it is determined whether or not the area S of the detected current is larger than the current integrated value Snori at the initially set level i.

That is, in this modification, steps S1 to S3 are performed in the same manner as in FIG. 12, and then the area S of the detected current in step S4 'is calculated from the current integrated value Snori at the initially set level i. It is determined whether it is large.

In the state where almost no current flows through the actuator 39, such as at the time of starting in the initial state, the temperature is low. Therefore, the current integration value Sno in the normal use state is obtained.
Often smaller than ri.

In such a case, the pulse ratio is increased by the process of changing the pulse ratio setting in step S10, and the process returns to step S1.

That is, when the actuator 39 is initially energized, the movement of the actuator 39 is slow because the temperature of the actuator 39 is low, and it takes time until the actuator 39 reaches a steady state. As in the present modification, at the time of the initial drive in which the detected current area S is small, the actuator 39 increases the drive pulse ratio until it reaches a steady value Snori corresponding to each speed setting level i. Try to reach steady speed.

If the determination in step S4 'is S> Snori, the processes in steps S5 to S8 are performed in the same manner as in FIG.

Therefore, according to the present modification, the temperature is low in the state where almost no current flows through the actuator 39 as in the start-up in the initial state, the current flowing therethrough is small, and the actuator 39 reaches the normal use state. In the absence state, the drive pulse ratio is quickly increased, and the state is set to reach the current integrated value in a normal use state.

That is, in the initial state, the actuator 39
It is not necessary to perform an operation of repeatedly moving between the Wide end and the Tele end to set a use state close to a normal zoom use state, and there is almost no waiting for such a time, so that it can be used quickly.

In the first embodiment, the control of the energization amount is performed by changing the pulse ratio by changing the pulse ratio setting as shown in FIG. In this case, the pulse ratio n /
400 to (n + 1) / 400 or (n-1) / 400
However, instead of this, for example, the area S> Sth
In the case of (S-S)
th) etc. a value proportional to the difference from the limit value a (S-Sth)
(Where a is, for example, 1
A positive value that is much smaller and a (S-Sth) is 4
A positive integer well below 00).

When the area S <Sth, the value b (Sth−S) proportional to the difference from the limit value such as (Sth−S) is increased as the process of step S10 in FIG. (Where b is a positive value sufficiently smaller than 1, for example, and b (Sth-S) is a positive integer sufficiently smaller than 400).

When the amount of energization is varied, instead of increasing or decreasing the pulse ratio, for example, the amplifier circuit 68 shown in FIG. 11 is constituted by a gain control amplifier, and the actuator 39 is controlled by controlling the gain control voltage of the gain control amplifier. May be changed by increasing or decreasing the amplitude of the drive pulse voltage applied to the power supply.

(Second Embodiment) Next, FIGS.
A second embodiment of the present invention will be described with reference to FIG. FIG. 18 shows a flowchart of the energization amount control according to the second embodiment, and FIG. 19 shows an operation explanatory diagram thereof. This embodiment measures the number of times of energization within a set time, and when the number of times of energization reaches a preset number of times, reduces the amount of energization, and is almost the same as the first embodiment. The purpose of this is to achieve.

When the power is turned on as shown in FIG.
The counter value of the energization frequency m is set in the counter circuit constituted by the CPU 63 and the like by the counter setting in step S11.

Then, the turning on of the zoom switch 40 in step S12 is accepted, and the zoom switch is turned on within the ton energization time ton seconds by the timer circuit in step S13.
It is determined whether or not it has been performed. If it has not been turned on, the process returns to step S11. If it has been turned on, the subtraction process of step S14 is performed and 1 is subtracted from the counter value. Then, it is determined whether or not the counter value in step S15 is equal to or less than 0. If the counter value is equal to or less than 0, a process of changing the pulse ratio setting is performed in step S19, and n of the pulse ratio n / 400 is reduced by, for example, one. It returns to step S11.

On the other hand, if the counter value does not satisfy 0 in step S15, the processing of the signal generation command in step S16, the address designation to the ROM 66 in step S17, and the energization of the drive waveform in step S18 are performed. That is, a normal zoom operation is performed.

FIG. 19 is a diagram for explaining the operation in this case. As shown in FIG. 19A, the timer circuit periodically outputs the time ton and the time ton so that the time ton when the energization is prohibited appears after the time ton when the energization is permitted.

When a remote switch such as the zoom switch 40 is turned on as shown in FIG. 19B, the counter value is sequentially reduced from the energization frequency m within the time ton as shown in FIG. The counter value is not changed within the time toff.

If, for example, the remote switch is pressed α times within the time ton, the counter value becomes m−α, and if this value is larger than 0, the zoom switch 4
The zoom movement operation corresponding to the operation of 0 is continued, and when it becomes 0 or less, the operation is continued by reducing the pulse ratio as shown in step S19.

According to the present embodiment, the zoom switch 40 is frequently operated within a predetermined time and the actuator 3
In the case where the temperature rises in the case of No. 9, since the amount of energization in that case is reduced, a smooth endoscope inspection function is ensured as in the first embodiment, and the durability is improved. There is an effect that can be improved.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 20 is a flowchart of an operation that retains the function of controlling the amount of energization according to the third embodiment, and FIG. 21 is an explanatory diagram of the operation. In the present embodiment, the energizing time is integrated within a set time, and when the energizing time reaches a preset energizing time, the amount of energizing is reduced, which is almost the same as the first embodiment. The purpose of this is to achieve.

In the present embodiment, step S in FIG.
As the processing of the 11 counter set, the energizing time ttot is set instead of the energizing number m. In this case, the energization time t
The digital value of tot is set as the count value in the counter circuit.

If it is determined in step S13 that the zoom switch 40 has been turned on within the time period ton seconds set by the timer circuit, if the zoom switch 40 has not been turned on, the process returns to step S12. Steps S16, S17, and S18 are performed (before performing steps S14 and S15), and after this step S18, steps S14 and S15 are performed, and step S1 is performed.
If the counter value of 5 ≦ 0, the pulse ratio setting is changed in step S19 and the process returns to step S12.

The present embodiment is partially different from the case of FIG. 18 in that the present embodiment measures the time during which the zoom switch 40 is pressed.
Basically, the same processing as in FIG. 18 is performed (the processing procedure in FIG. 18 can be changed as shown in FIG. 20 by changing the number of energizations by 1).

In the subtraction process in step S14, the time ti during which the zoom switch 40 is pressed is subtracted from the counter value. Otherwise, the same processing as in the second embodiment is performed.

In this embodiment, when the remote switch such as the zoom switch 40 is turned on as shown in FIG. 21B with respect to the time setting by the timer circuit of FIG. As shown in the figure, the ON time is subtracted from the energization time ttot of the counter value within the time ton, and the counter value is not changed within the time toff.

Then, for example, a value ttot obtained by subtracting the total time during which the remote switch is pressed within the time ton from ttot.
The operation is continued until − (t1 + t2 + t3 +... + Tα) becomes 0 or more, and when it becomes 0 or less, the pulse ratio is reduced and the operation is continued as shown in step S19.

According to the present embodiment, the actuator 3
9 is suppressed not only when the zoom switch 40 is pressed intermittently but also continuously when the zoom switch 40 is pressed.
Even when is pressed, energization for a predetermined time or more can be limited or prohibited. The other effects are almost the same as those of the first embodiment.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIGS. 22 (A) and 22 (B) show the current waveforms flowing through the actuator 39 when energizing in the Tele direction and energizing in the Wide direction by solid lines.
Actuator 3 in a state where it abuts on end e (wide-angle end)
The waveform of the current flowing through 9 is indicated by a dashed line, and FIG. 23 shows, for example, a state in which the state of abutment at the Tele end is displayed on a monitor.

In the present embodiment, when the actuator 39 is located at either the enlarged end or the wide-angle end, if the electric current is further applied in the abutting direction, all the kinetic energy supplied to the actuator 39 is changed to thermal energy. Therefore, the amount of heat generated by the actuator 39 significantly increases as compared with the normal operation, and the collision detection is performed by using the phenomenon that the current value also increases accordingly.

That is, a value slightly lower than the positive current area of the current waveform shown by the one-dot chain line in FIG.
Is detected by a current detection circuit and compared with this threshold value to detect whether the state is at the enlarged end or the wide-angle end.

When it is determined by comparison that the end is the enlarged end or the wide-angle end, the fact is displayed on the monitor as shown in FIG. Alternatively, the user may be warned with a buzzer sound.

When the state of the wide-angle end or the wide-angle end is detected, if the operation in the direction of hitting the wide-angle end or the wide-angle end is performed for a set time or more, the power supply is stopped or the power supply is stopped. The amount may be limited. In this way, it is possible to prevent the operation in the direction in which the actuator 39 comes into contact with the enlarged end or the wide-angle end from being performed extra, and the actuator 39 from being unnecessarily heated.

The threshold value used in this embodiment is
The threshold value Sth set in the first embodiment may be different from the threshold value Sth, and the first embodiment and the present embodiment may be used simultaneously.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described. In the present embodiment, the contents described in the first to fourth embodiments are applied to a visual field conversion mechanism of an endoscope. The configuration of the visual field conversion mechanism mounted on the endoscope end is different from the first to fourth embodiments.

FIG. 24 shows the configuration of the distal end portion 13 of the endoscope 2. The distal end portion main body 91 constituting the distal end portion 13 includes:
The objective optical system 34 is arranged in the axial direction of the distal end portion main body 91 (the left-right direction in FIG. 24), and the CCD 35 is arranged at the image forming position.

A mirror 101 is housed in a notch provided at a position forward of the optical path of the objective optical system 34. One end of the mirror 101 is rotatably supported, and the mirror 101 is located at a position closer to the other end than this one end. A pin provided on the output shaft 39a of the actuator 39 is engaged with the provided elongated hole (not shown) and is rotatably connected.

An actuator 39 is mounted in a recess provided in the distal end body 91 near the base end of the output shaft 39a. The actuator 39 is connected to a zoom control device 6 (however, in the present embodiment, it is referred to as a visual field conversion control device because it performs a visual field conversion, as described in the first embodiment). The CCD 35 is also connected to the CCU 4 through the amplifier 36.

By operating the zoom switch 40 or the remote switch 59 including the foot switch 7, a drive signal is applied from the drive unit 51 to the actuator 39 via the control circuit 53, and the output shaft 39a is moved to the position shown in FIG. The mirror 101 is moved in the direction shown by the arrow, and the mirror 101 is rotated around one end by this movement, so that the direction of the field of view can be changed or the field of view can be changed.

For example, the light coming from the direction of the light beam 102 in FIG. 24 is reflected by the mirror 101, passes through the optical axis of the objective lens system 34, and enters the CCD 35. In other words, in this state, the direction of the light beam 102 becomes the viewing direction, and when the remote switch 59 is operated to change the tilt angle of the mirror 101, the viewing direction changes.

Next, the operation of the present embodiment will be described. When the actuator 39 is driven by a drive pulse from the drive unit 51, the mirror 101 rotates around one end of the mirror 101. At this time, the light coming from the direction of the light beam 102 in FIG.
4 and is incident on the CCD 35. That is, mirror 1
By 01, the optical axis is bent. Remote switch 59
The operation of the actuator 39 when is pressed is the first to fourth operations.
Since the content is the same as that described in the embodiment, the description thereof will be omitted.

The role of the mirror 101 in the present embodiment is as follows.
Although the direction of the incident light is variably controlled, the present invention is not limited to this, and the light emitted from the endoscope 2 may be controlled as in the following modified examples.

For example, a laser probe or a laser diode may be provided in place of the CCD 35 to variably control the direction in which laser light is emitted. Also,
Instead of the CCD 35, an illumination fiber may be arranged to variably control the direction in which the illumination light is emitted. In this case, the objective optical system 34 functions as a lens system for projecting or irradiating laser light or illumination light emitted from the end face of the illumination fiber. Therefore, in practice, it is preferable to use a lens system having a configuration suitable for such a function.

This embodiment has the following effects. The improvement in the operability of the visual field conversion according to the present embodiment is semantically the same by reading the effects described in the first to fourth embodiments in terms of the operability of the visual field conversion (the same configuration). Control device).

(Sixth Embodiment) Next, an eighth embodiment of the present invention will be described with reference to FIGS. In this embodiment, the piezoelectric element 50 described in the first embodiment is used.
The drive control means of the actuator 39 is applied to the bending drive of the endoscope.

As shown in FIG. 25, each bending piece 111 constituting the bending portion 14 is rotatably connected (pivotally attached) by a pivot pin 112 between adjacent bending pieces 111 at, for example, a left-right position. As a result, they are connected to be able to bend vertically.

The angle wires 113A and 113B for bending the bending portion 14 in the vertical direction are provided on each bending piece 111.
Are inserted along the inner wall in the up-down direction at the upper end, for example, the upper end 114A and the lower end 11 of the foremost bending piece 111.
4B is fixed by brazing or the like.

Further, the angle wires 113A, 113B
The rear end of the piezoelectric actuator 115 is disposed at an upper and lower position in the flexible tube portion 15 behind the bending portion 14 or the like.
A, 115B. The two piezoelectric actuators 115A and 115B have the same structure. For example, the configuration of the piezoelectric actuator 115A is shown in FIG.

A movable body 117 which is in sliding contact with the inner peripheral surface of the stationary member 116 is accommodated inside the cylindrical stationary member 116, and the front end of a laminated piezoelectric element 118 is attached to the movable body 117. .

The movable body 117 has a plurality of legs 119 formed of an elastic member extending rearward, and the rear end of each leg 119 has a biasing force for elastically expanding. Part 119
A projection 120 for sliding contact is provided on the outer side of the rear end, and elastically presses against the inner peripheral surface of the stationary member 116. By this pressing, a frictional force acts between the stationary member 116 and the moving body 117. I have to.

For example, a front end of a laminated piezoelectric element 118 formed by laminating a plurality of piezoelectric crystal plates is fixed to the moving body 117, and a rear end side of the piezoelectric element 118 is a free end which can be freely displaced. , Protruding rearward from the moving body 117. A flexible lead wire 121 provided so as to be electrically connected to the electrode of the piezoelectric element 118 is connected to the drive unit 51 via the endoscope.

By operating the remote switch 59, a drive signal as shown in FIG. 7 is applied from the drive unit 51 to the piezoelectric actuators 115Ab and 115B. The stationary member 116 is fixed to the flexible tube 15 or the like by bonding the outer peripheral surface thereof.

Further, a bending switch 40 in which the zoom switch 40 is replaced with another is provided without providing the bending operation knob 16 in the first embodiment.

In this embodiment, the bending switch 40
Is operated, the piezoelectric actuator 115A disposed on the upper side and the piezoelectric actuator 115B disposed on the lower side
, A driving signal for driving in the opposite direction is applied (see the following operation).

Next, the operation of the present embodiment will be described. The endoscope is connected to the zoom control device 6 (in this case, read as a bending control device) 6 shown in FIG. 1 and the remote switch 59 (the bending switch 40 or the foot switch 7 thereof) is operated. Can be curved.

The manner of bending in this case can be substantially explained by reading the contents of the first embodiment and the like. For example, in the speed mode, for example, when the T switch 40T associated with the upward bending switch of the bending switch 40 is operated (ON), the driving pulse of FIG. 7B is applied to the piezoelectric actuator 115A, and the angle wire is turned on. 113A is moved to the rear side to pull the upward portion of the bending piece 111 to the rear side, and the driving pulse of FIG. 7A is applied to the piezoelectric actuator 115B to move the angle wire 113B to the front side. Become relaxed. Then, the bending piece 111 is bent upward.

On the other hand, when the W switch 40W associated with the downward bending switch of the bending switch 40 is operated (ON), the driving pulse shown in FIG. 7B is applied to the piezoelectric actuator 115B and the angle wire 11 is turned on.
3A pulls the lower part of the bending piece 111 being moved to the rear side to the rear side, and the driving pulse of FIG. 7A is applied to the piezoelectric actuator 115A to move the angle wire 113A to the front side. Become relaxed.
Then, the bending piece 111 is bent downward.

When the foot switch 7a or the foot switch 7b is operated, the bending piece 111 is bent upward or downward. In other modes and the like, it can be almost explained by reading the operation of the first embodiment.
The description is omitted. It should be noted that the bending speed may be operated in two types, high speed / low speed, instead of one type.

Further, in the present embodiment, the present invention is applied to, for example, vertical bending, but may be applied to, for example, vertical and horizontal bending. In this case, a piezoelectric actuator similar to that in the vertical direction may be provided in the horizontal direction, or a switch for bending in the horizontal direction may be further provided as the bending switch 40. Further, in order to enable operation by the foot switch 7, a foot switch for bending in the left-right direction may be further provided.
This embodiment has the effect of replacing the zoom control function of the first to fourth embodiments with a curve.

(Seventh Embodiment) Next, a seventh embodiment of the present invention will be described with reference to FIG. In this embodiment, the piezoelectric actuator is applied to a treatment tool raising mechanism, and in this case, control is performed by a zoom control device (in this case, read as a treatment tool raising control device) 6 according to the first embodiment or the like. It is like that.

FIG. 27 shows the structure of the distal end portion 13 of the side-viewing type endoscope. An illumination lens 131 for side-view illumination and an objective lens system 132 for side-view observation are arranged adjacent to the base end side of the tip section main body 130 constituting the tip section 13. Then, the illumination light emitted from the distal end face of the light guide fiber 133 connected to the light source device 3 of FIG. 2 is expanded by the illumination lens 131 and emitted to the side, and the illuminated subject such as the affected part is illuminated. Is imaged through the objective lens system 132 on the CCD 134 disposed at the image forming position.

The CCD 134 is connected to the CCU 4 shown in FIG. 2, and a subject image is displayed on the color monitor 5 via the video signal processing circuit 37 in the CCU 4.

The distal end portion 13 has a treatment instrument channel 1.
A treatment instrument raising mechanism storage section 136 is provided by cutting out a position desired by the distal end opening 35 from the side of the distal end body 130, and a treatment instrument raising table 137 is stored near the bottom thereof.

The treatment instrument raising table 137 is disposed so as to face the distal end opening of the treatment instrument channel 135, and the base end of the treatment instrument raising table 137 is fixed to the distal end main body 13 by a pin 138.
It is pivotally attached to zero.

When the distal end of the treatment instrument 139 inserted through the treatment instrument channel 135 is projected from the distal end opening of the treatment instrument channel 135, the treatment instrument 139 is regulated in accordance with the inclination angle of the treatment instrument raising base 137. The protruding direction (leading-out direction) of the tip side of the tool 139 can be controlled.

A piezoelectric actuator 140 is provided on the back side of the treatment instrument raising table 137. In other words, the distal end body 130 on the back side of the treatment instrument raising table 137 has the distal end 13.
The guide hole 141 is provided in the axial direction of the
A moving body 142 is disposed on 41 such that a leg 143 extending to the moving body 142 slides on the moving body 142 to exert a frictional force.

A rear end of the laminated piezoelectric element 144 is fixed to the moving body 142, and a front end of the piezoelectric element 144 is a free end. A lead wire 145 is connected to the front end side of the piezoelectric element 144, and the lead wire 145 is connected to the drive unit 51 in FIG.

By operating the remote switch, the piezoelectric actuator 140 is moved in the axial direction of the guide hole 141 so that the inclination angle (elevation angle) of the treatment instrument elevator 137 can be variably controlled.

The treatment instrument raising base 137 is urged by an elastic body such as a spring (not shown) so as to rotate toward the piezoelectric actuator 140 disposed on the back side (front side). 137 is the piezoelectric actuator 14
At 0, the inclination angle is regulated. Then, for example, by moving the piezoelectric actuator 140 to the rear side from this state, the treatment instrument raising table 137 stands up to the side.

Next, the operation of the present embodiment will be described. By operating the remote switch, the treatment tool raising base 137 can be raised via the treatment tool raising control device 6 as described in the first embodiment.

The treatment instrument 139 in this case is not limited to the forceps, but may be, for example, a laser probe, a clip, or an endoscope having a thin insertion portion. This embodiment has an effect obtained by replacing the first to fourth embodiments. It should be noted that embodiments and the like configured by partially combining the above-described embodiments and the like also belong to the present invention.

[Supplementary notes] (1) Supplementary items An endoscope having a driven body driven by a piezoelectric actuator, a control device detachably connected to the endoscope for driving and controlling the piezoelectric actuator, and a switch for generating a drive signal for the piezoelectric actuator In the endoscope apparatus, in the control device, an energization amount detection unit for detecting an energization amount to the piezoelectric actuator, and a predetermined limit value related to the energization amount are set, and the detection detected by the current detection unit is performed. An endoscope apparatus comprising: comparison means for comparing the magnitude of the value with the limit value; and power supply control means for controlling the amount of power supply to the piezoelectric actuator based on a comparison result by the comparison means. .

1-0. There is provided a presenting means for presenting the comparison result. 1-1. The energization amount detection means detects an injection current amount to the piezoelectric actuator, and the energization amount control means decreases the energization amount at a predetermined rate when the injection current amount exceeds the limit value. It is characterized in that it is controlled so that

1-1-1. The energization amount is adjusted by increasing or decreasing the drive pulse ratio of the piezoelectric actuator. 1-1-2. The amount of current is adjusted by increasing or decreasing the drive pulse voltage amplitude of the piezoelectric actuator.

1-2. The energization amount detection unit detects the amount of injection current to the piezoelectric actuator, and the energization amount control unit returns the energization amount to a normal value when the amount of injection current falls below the limit value. It is characterized by the following control. 1-2-1. The energization amount is adjusted by increasing or decreasing the drive pulse ratio of the piezoelectric actuator. 1-2-2. The amount of current is adjusted by increasing or decreasing the drive pulse voltage amplitude of the piezoelectric actuator.

1-3. The energization amount detection unit detects an amount of current injected into the piezoelectric actuator, and the energization control unit controls the amount of energization to increase or decrease at a rate corresponding to a difference between the amount of injection current and the limit value. It is characterized by doing. 1-3-1. The energization amount is adjusted by increasing or decreasing the drive pulse ratio of the piezoelectric actuator. 1-3-2. The amount of current is adjusted by increasing or decreasing the amplitude of the drive pulse voltage of the piezoelectric actuator.

1-4. The energization amount detection means is means for detecting the number of energizations to the piezoelectric actuator per unit time. 1-5. The power supply amount detecting means is a means for detecting a power supply time per unit time to the piezoelectric actuator. 1-6. The energizing amount detecting means is means for detecting an integrated value of energizing time to the piezoelectric actuator.

1-7. The energization amount detection unit detects the amount of current injected into the piezoelectric actuator, and the energization amount control unit controls the amount of energization to the piezoelectric actuator so that the amount of injection current becomes a predetermined value. Features. 1-7-1. The energization amount is adjusted by amplifying a drive pulse ratio of the piezoelectric actuator. 1-7-2. The amount of current is adjusted by increasing or decreasing the drive pulse voltage amplitude of the piezoelectric actuator.

1-8. The energization control means sets the limit value so that the energization amount exceeds the limit value when the piezoelectric actuator reaches a movement stroke end, and limits the energization amount to the piezoelectric actuator. And 1-9. As the predetermined limit value in the control device, a first limit value and a second limit value different from the first limit value are set. The second limit value is set so that the amount exceeds the second limit value, and the amount of energization of the actuator is limited.

(2) Prior art for supplementary items 1-1 to 1-6 Same as described in the text (conventional technology) (3) Object for supplementary items 1-1 to 1-6 Same as the description (5) Prior art for supplementary items 1 to 7 In addition to the content described in Japanese Patent Application No. 10-117475 (2), when the zoom speed is low during the initial operation of the endoscope apparatus, the speed is increased. It reciprocates between the wide-angle end and the wide-angle end until a steady state is reached, but this method takes a long time to set up and is inconvenient. (6) Object for additional items 1-7 In addition to the contents described in (3) above, initial setup is facilitated.

(7) Prior Art for Additional Items 1-8 JP-A-9-322566 In addition to the contents of the above (2), in order to detect the position of the piezoelectric actuator, an electrode for position detection is provided at one end of the piezoelectric actuator. However, it is difficult to manufacture elements and process electrodes. (8) Object to additional items 1-8 In addition to the content of the above item (3), an endoscope device that can easily manufacture a piezoelectric actuator is provided.

[0159]

As described above, according to the present invention, an endoscope having a driven body driven by a piezoelectric actuator, and a control for drivingly controlling the piezoelectric actuator which is detachably connected to the endoscope. An endoscope apparatus comprising: a device; and a switch for generating a drive signal for the piezoelectric actuator. In the control device, an energization amount detecting means for detecting an energization amount to the piezoelectric actuator; Comparing means for comparing the magnitude of the detected value detected by the current detecting means with the limit value, and varying the amount of current supplied to the piezoelectric actuator based on the comparison result by the comparing means. Since the power supply control means is provided for controlling, even if the detected value exceeds the limit value, the function to drive the driven body by reducing the power supply amount is provided. To ensure smooth endoscopic observation, and to suppress the heat generation due to a decrease in current amount can prevent a decrease in durability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an appearance of an endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing the overall configuration of the endoscope apparatus.

FIG. 3 is a perspective view showing the appearance of the endoscope.

FIG. 4 is a perspective view showing a structure of a distal end portion of the endoscope with a part cut away.

FIG. 5 is an external view showing an external appearance of an actuator provided at a distal end portion.

FIG. 6 is a sectional view showing the structure of the actuator.

FIG. 7 is a diagram showing a waveform of a drive signal.

FIG. 8 is a front view of the zoom control device.

FIG. 9 is a view showing a display example of a monitor screen.

FIG. 10 is a block diagram illustrating a schematic configuration of a zoom control device.

FIG. 11 is a block diagram showing a functional configuration of a zoom control device.

FIG. 12 is a flowchart illustrating an operation when a zoom switch is turned on.

FIG. 13 is a diagram showing a drive pulse ratio.

FIG. 14 is a diagram illustrating a waveform and the like of a current detected by a current detection circuit.

FIG. 15 is a diagram showing a magnitude relationship of current integrated values including a limit value set by a limit value setting circuit.

FIG. 16 is a flowchart illustrating an operation when a zoom switch is turned on in a modification of the first embodiment.

FIG. 17 is a diagram showing a drive pulse ratio initial set value for each level in a speed mode, a current integrated value in a normal state, and the like.

FIG. 18 is a flowchart illustrating an operation when a zoom switch is turned on according to the second embodiment of the present invention.

FIG. 19 is an operation explanatory diagram of the second embodiment.

FIG. 20 is a flowchart showing an operation when a zoom switch is turned on in the third embodiment of the present invention.

FIG. 21 is an operation explanatory diagram of the third embodiment.

FIG. 22 is a diagram showing current waveforms at the enlarged end and the wide-angle end for explaining a fourth embodiment of the present invention.

FIG. 23 is a view showing a display example of a monitor screen.

FIG. 24 is a sectional view showing a configuration of a distal end portion of an endoscope according to a fifth embodiment of the present invention.

FIG. 25 is a diagram showing a bending drive mechanism of an endoscope according to a sixth embodiment of the present invention.

FIG. 26 is a sectional view showing the structure of a piezoelectric actuator according to a sixth embodiment.

FIG. 27 is a sectional view showing a configuration of a distal end portion of an endoscope according to a seventh embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Endoscope apparatus 2 ... Endoscope 3 ... Light source apparatus 4 ... CCU 5 ... Color monitor 6 ... Zoom control apparatus 7 ... Foot switch 8 ... Insertion part 9 ... Operation part 13 ... Tip part 34 ... Objective optical system 35 ... CCD 38 Zoom lens 39 Actuator 40 Zoom switch 50 Piezoelectric element 51 Drive unit 53 Control circuit 56 Power switch 59 Step mode switch 60 Speed mode switch (continuous movement mode switch) 62 I / O 63 ... CPU 64 ... RAM 65 ... FPGA 66 ... ROM 67 ... D / A converter 69 ... Current detection and integration means 71 ... Electrification control circuit 75 ... Comparison circuit 76 ... Limit value setting circuit 77 ... Drive pulse ratio setting circuit

Claims (1)

[Claims] 1. An endoscope having a driven body driven by a piezoelectric actuator, a control device detachably connected to the endoscope to drive and control the piezoelectric actuator, and generating a drive signal for the piezoelectric actuator. An endoscope device comprising: a switch for causing a current to flow through the piezoelectric actuator in the control device; and setting a predetermined limit value related to the current to the piezoelectric actuator in the control device; Comparing means for comparing the magnitude of the detection value detected by the and the limit value,
An endoscope apparatus comprising: an energization control unit that controls an amount of energization to the piezoelectric actuator based on a comparison result by the comparison unit.