JP5727336B2 - Conveying method - Google Patents

Description

The present invention relates to a method for transporting a transported object , and more particularly, to a transport method using a device having means for separating the transported object in a transporting direction, which is suitable when transporting a transported object such as a fine electronic component by vibration. .

  In general, there is known a vibration type conveying device called a parts feeder or a linear feeder that conveys a conveyed product on a predetermined conveying path by vibration. In this device, when transporting a transported object along a transport path, the transported object that moves continuously in the direction of transport to perform sorting, alignment, posture change, individual inspection, etc. It is known to provide means for separating. As this means, the inclination angle of the conveyance direction of the conveyance path is changed at a predetermined position, thereby changing the posture of the conveyance object, or by moving the conveyance object from the predetermined position on the downstream side at a higher speed than the upstream side. An interval has been provided between the front and rear conveyed items.

  However, in recent years, the objects to be transported have become finer, and higher transport speeds and transport amounts have been demanded. Therefore, the above-described change in posture and the difference in transport resistance caused by changing the tilt angle of the transport path are utilized. In the method, the conveyed product cannot be reliably separated into front and back, and as a result, there is a problem that a detection error of the conveyed product occurs and a problem occurs. Therefore, as shown in Patent Documents 1 to 3 below, a method has been proposed in which a subsequent transported object is temporarily stopped by suction to create an interval between the front transported object.

  In any of the methods described in the above documents, the opening shape of the suction port is circular.

JP-A-6-246236 JP 2002-137820 A JP 2003-3000613 A

  However, when the opening shape of the suction port is circular, there is a problem that the suction force exerted on the component cannot be changed quickly.

  Therefore, an object of the present invention is to increase the change rate of the suction force when the conveyance state of the conveyed product by the vibration type conveyance device is controlled by the suction force.

  In view of such a situation, the method for transporting a transported object of the present invention is a transporting method for transporting a transported object having a substantially rectangular parallelepiped shape by means of a vibratory transport device. A transport body provided with a transport path for transporting the transported object along a transport surface to be supported and guided; and the transport direction in a mode in which the transported object is transported in the transport direction on the transport path. A vibration mechanism that vibrates at a time, a suction port having a rectangular opening shape that opens on the transport surface of the transport path, and the presence or absence of suction force at the suction port can be switched, or the suction force can be increased or decreased. Suction action means.

According to the present invention, by making the shape of the opening of the suction port rectangular, the ventilation resistance or pressure loss can be reduced, and the suction force can be changed more rapidly than when it is circular. The opening shape of the suction port preferably has two opposite sides parallel to the carrying direction and two opposite sides perpendicular to the carrying direction. Moreover, it is preferable that the opening shape has an opening length smaller than the length along the conveying direction of the conveyed product and an opening width smaller than the width in the direction orthogonal to the conveying direction of the conveyed item .

  The present invention includes a transport body having a transport path through which a transported object is transported. The conveyed product is substantially a rectangular parallelepiped, and examples thereof include parts such as electronic components such as surface-mounted resistors, capacitors, and ICs. The conveyance path is often configured as a groove-shaped or one-groove-shaped path formed on the surface of the conveyance body, and is formed in a spiral shape or a straight line extending in the conveyance direction. The conveyance path includes a conveyance surface that supports and guides the conveyance object. Typical examples of the transport body include a bowl-shaped transport body having a spiral transport path on the inner surface, and a linear transport body having a straight transport path on the upper surface.

  The transport body is vibrated in the transport direction (front and back in the transport direction) by the vibration mechanism. The vibration mechanism typically transmits a vibration generation source such as an electromagnetic drive body or a piezoelectric drive body, vibrations generated by the vibration generation source to the transport body, and supports the transport body in a state where it can vibrate. Therefore, an elastic member such as a leaf spring is used. This vibration mechanism vibrates the transport body in such a manner that a forward force necessary to move the transported object on the transport path in the transport direction along the transport path is generated. Usually, the conveyance surface (inner bottom surface) of the conveyance path with which the conveyed product can contact is vibrated obliquely upward in the conveyance direction. The vibration having the vibration direction obliquely upward in the direction of conveyance advances the conveyance object diagonally upward, and immediately after that, the conveyance surface returns obliquely downward in the direction opposite to the conveyance direction. Repeat the cycle of continuing to move forward while staying away from the surface. As described above, the vibration period of the transport body includes the forward period in which the transport body advances in the transport direction and the reverse period in which the transport body moves backward.

  The suction port opens in the transport path and is essentially fixed to the transport body. In particular, it is preferable that the suction port is formed so as to open on a conveyance surface with which a conveyed product can contact, for example, an inner bottom surface or an inner side surface of the conveyance path. When a ceiling surface exists in the conveyance path, it may be open to the ceiling surface. The suction port is connected to a suction device constituted by an exhaust device such as a vacuum pump or an ejector via a suction path. The structure of the suction port is not particularly limited, but in order to efficiently apply the suction force to the transported object, the opening area is smaller than the projection surface with respect to the transport surface in the transport posture of the transported object, and the transported object on the transport path It is preferable to have a shape that does not hinder the conveyance, that is, a structure having an opening surface along the conveyance direction.

  In the suction path, there is provided a suction operation means configured such that the presence or absence of a suction force at the suction port can be switched or the suction force can be increased or decreased, such as an electromagnetic valve or a pneumatic operation valve. The suction operation means may be an opening / closing mechanism for opening / closing the suction port itself. The suction operation means may include a drive circuit that drives the electromagnetic valve, the pneumatic operation valve, the opening / closing mechanism, and the like.

  The suction control means controls the suction operation means. It is preferable that the suction control means switches the presence or absence of the suction force or increases or decreases the suction force in synchronization with the vibration cycle of the carrier. As long as the control of the suction control means is performed at a timing that is synchronized with the vibration cycle of the transport body as a result, the suction control means may be any one, but typically, the vibration cycle of the transport body, the excitation mechanism And a detection unit for detecting a control period of the vibration mechanism. In this case, a dedicated detector that detects the vibration period of the carrier may be used as the detection unit, but the detection signal, the control vibration, the drive signal, and the like that are used for the control drive of the vibration mechanism are taken in as they are. It is preferable in terms of the device configuration.

  The suction control means can switch the presence / absence of the suction force at the suction port or increase / decrease the suction force for each vibration cycle, so that the acceleration / deceleration of the conveyed product can be caused more reliably. In particular, for each vibration cycle of the conveying body, in synchronization with the vibration cycle, a suction period (Tc) in which a suction force is generated or a suction force is increasing, and a period in which the suction force is stopped Alternatively, it is preferable to provide a non-suction period (Td) in which the suction force is decreasing. By providing a suction period and a non-suction period synchronized with the vibration period for each vibration period, the fluctuation mode of the suction force is made steady for each vibration period, so that the separation effect of the conveyed product can be further stabilized. However, as long as the control timing is synchronized with the vibration cycle, the presence / absence of suction force may be switched or increased / decreased for each of the plurality of vibration cycles, or a suction period over a plurality of cycles may be provided. Good.

  In the case where the suction period (Tc) is provided for each vibration period of the carrier, the relationship between the forward period and the reverse period of the vibration period is set by the phase of the suction period and the length (ratio) of the period. Can do. At this time, it is preferable that the suction period includes a point in time when the conveyance body is at a front end position or a rear end position of vibration. In this way, by changing the phase of the suction period, it is possible to adjust the decelerating action or the accelerating action of the conveyed product by the suction force in detail and easily. In particular, in the deceleration mode, it is easy to avoid a complete stop of the conveyed product without setting the suction period short.

  In this case, in the suction period (Tc), the conveyed product according to the size (Tcb / Tb or Tcb / T) of the time corresponding to the reverse period (Tb) (the reverse suction time Tcb described later). Is slowed down. Further, when the transport speed of the transported object upstream of the suction port is somewhat lower than the forward speed in the forward period of the transport body (when the transport speed is relatively low), the suction period (Tc) The size and ratio (Tcb / Tb or Tcb / T) of the time corresponding to the reverse period (Tb) (reverse suction time Tcb described later) and the time corresponding to the forward period (advance suction time Tca described later) The conveyed product is accelerated or decelerated according to the balance with the size and ratio (Tca / Ta or Tca / T). The level of the conveyance speed varies depending on the vertical inclination angle in the vibration direction of the conveyance body, the friction coefficient between the conveyance object and the conveyance surface, and the like.

  It is desirable that the suction port has an opening length (La) in the transport direction that is ½ or less of a length (Lo) along the transport direction of the transported object. Thereby, since ratio of opening length (La) with respect to length (Lo) can be made small, the suction force by a suction port can be reliably given to a specific conveyance thing. Generally, by reducing the above ratio, when the conveyed product crosses the suction port, the period during which the conveyed item covers the entire suction port can be lengthened, and the number of vibration cycles in the period can be increased. Since a suction force can be applied to a single conveyed object a plurality of times, a more reliable deceleration or acceleration action can be obtained. On the other hand, regarding the shape of the suction port itself, it is preferable that the opening length (La) has an opening shape smaller than the opening width (Wa) in the direction orthogonal to the transport direction. In this way, it is possible to secure a large range along the transport direction in which the transported object can close the suction port while suppressing a decrease in the opening area in which the suction action occurs, so that the suction force is more reliably applied to the transported object. Can act on.

  Control of the above-mentioned conveyance state can be performed, for example, in order to separate a certain conveyance object from other conveyance objects before and after. This separation of the conveyed product is performed when the conveyed product is inspected while avoiding the influence of other conveyed products. In this case, the inspection position is set downstream of the suction port formation position. As described above, an inspection unit having an inspection position for inspecting a conveyed product may be provided on the downstream side of the suction port. In this case, processing means for performing various processes on the transported object, for example, alignment, sorting, posture change, etc. of the transported object may be provided in accordance with the inspection result of the transported object by the inspection means. Note that, regardless of the presence or absence of the inspection means, there may be a case where a processing means having a processing position downstream from the formation position of the suction port is provided.

  According to the present invention, since the suction force can be changed quickly, it is possible to control the transport state of the transported object by the suction force at a high speed, and it is possible to cope with high speed transport. Can play.

The schematic block diagram which shows the control system of the vibration type conveyed product conveying apparatus of embodiment which concerns on this invention. The side view which shows the apparatus structure of the embodiment. The front view (A) and a top view (B) which show a mode that the conveyance body of the embodiment was removed. 4 is a timing chart showing an example of a vibration period (detection signal) E, a control signal F, a drive signal G, a valve opening / closing state H, and a suction force I at a suction port of the transport body of the embodiment. The side view which shows the separation aspect (acceleration mode) of the conveyed product on the conveyance path in the embodiment. The side view which shows the separation aspect (deceleration mode) of the conveyed product on the conveyance path in the embodiment. Sectional drawing (a)-(c) which shows the example of the positional relationship of the structure of a conveyance path, and a conveyed product. The enlarged view which shows the structure of the conveyance path of an Example. The graph which shows the actual measurement data of the Example of acceleration mode. The graph which shows the actual measurement data of the Example of deceleration mode.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Initially, the schematic structure of the vibration type conveyed product conveying apparatus of this embodiment is demonstrated with reference to FIG.1 and FIG.2.

  FIG. 1 is a schematic configuration diagram showing a schematic configuration of an excitation drive circuit 100 that constitutes a control system used in the vibration type conveying apparatus according to the present invention. The excitation drive circuit 100 rectifies and smoothes the AC voltage supplied from the commercial power source 1 and steps down the voltage as necessary to supply a required DC voltage (hereinafter simply referred to as “supply voltage”) Vo. 120 and an inverter 130 for converting the supply voltage Vo supplied from the DC power source 120 into an AC output voltage Vp having a predetermined frequency. The output voltage Vp supplied from the inverter 130 is applied via the inductors 140 and 150 to the piezoelectric element 3 that is an excitation element of the vibration generation source. These inductors 140 and 150 are ripple removing choke coils. Only one of the inductors 140 and 150 may be provided, but it is preferable to provide both of the inductors 140 and 150 on both sides of the piezoelectric element 3, which is preferable in terms of noise countermeasures.

  Further, the excitation drive circuit 100 includes a detection transformer 170 that is a voltage detection means for detecting the voltage Vs across the piezoelectric element 3, and the output of the detection transformer 170 is connected to the control unit 180. The control unit 180 is configured by, for example, a microprocessor unit (MPU) or the like, and outputs a control signal S according to a voltage detection value Vd indicating the voltage Vs across the piezoelectric element 3 detected via the detection transformer 170. ing. The control signal S substantially includes a frequency command value that determines the frequency of the inverter 130 and a voltage command value that determines the voltage value, and is input to the PWM circuit 190 that is an inverter drive circuit. D is output to drive the switching elements 131, 132, 133, and 134 including FETs of the inverter 130, and the inverter 130 generates the predetermined AC output voltage Vp by PWM driving.

  The output voltage Vp of the inverter 130 is set by the width (duty ratio) and the period T of the rectangular pulse P corresponding to the drive signal D of the PWM circuit 190. For example, the effective voltage value changes as the duty ratio of the rectangular pulse P changes according to the drive signal D. Further, the drive frequency (f = 1 / T) is changed by changing the period t of the rectangular pulse P or the alternating period T of the positive and negative rectangular pulses P in accordance with the drive signal D. The duty ratio and frequency are controlled by the control signal S output from the control unit 180. The waveform of the output voltage Vp shown in the frame of the two-dot chain line in FIG. 1 is a schematic diagram showing only the principle, and does not accurately show the relationship between the switching cycle t of the inverter and the cycle T of the output voltage Vp. Absent.

  The control unit 180 of the present embodiment includes a setter 181 that can set the voltage reference value Vr and a setter 182 that can set the frequency reference value fr. The control unit 180 and the PWM circuit 190, which are inverter control means, control the inverter 130 so that the voltage value and the frequency correspond to the voltage reference value Vr and the frequency reference value fr. Further, the voltage Vs across the piezoelectric element 3 is detected via the detection transformer 170, and the control unit 180 can control the voltage Vs across the piezoelectric element 3 to be kept constant according to the voltage detection value Vd. ing. For example, the voltage Vs at both ends of the piezoelectric element 3 is directly detected, and the inverter 130 is controlled so as to keep the voltage detection value Vd corresponding to the voltage Vs at both ends constant (for example, the voltage reference value Vr). Compared to when the inverter is operated only by setting the voltage command value to the inverter, it is always unaffected by fluctuations in the size and number of vibration sources (fluctuation in drive current) or fluctuations in vibration load. A stable driving voltage can be provided. In addition, since an accurate drive voltage can be applied to the vibration generation source, the vibration generation efficiency can be increased by optimizing the drive voltage.

  In the present embodiment, the resonance frequency of the piezoelectric element 3 can be easily detected only by the above configuration. For example, the control unit 180 monitors the voltage detection value Vd while generating the control signal S so as to gradually change (sweep) the drive frequency while keeping the output voltage Vp supplied by the inverter 130 constant. The minimum point of the voltage detection value Vd (the impedance minimum point of the vibration generating source) can be detected as the resonance frequency. Further, when the drive frequency is gradually changed while performing the feedback control for keeping the voltage detection value Vd detected through the detection transformer 170 constant as described above, the voltage command value ( For example, the maximum point of the difference Vr−Vd) between the voltage reference value Vr and the voltage detection value Vd can be detected as the resonance frequency.

  The resonance frequency can be detected manually. For example, the resonance frequency can be automatically detected by a resonance point detection program that can be executed by the control unit 180. In other words, the drive frequency is changed (sweep) at a constant step amount by a control signal S, and the voltage detection value Vd (without voltage control) or the voltage command value (with voltage control) is monitored. Then, the frequency sweep may be continued until the minimum point of the voltage detection value Vd or the maximum point of the voltage command value is reached. In this case, in order to detect the resonance point more accurately, the frequency change direction is reversed and the step amount is reduced when the minimum point of the voltage detection value Vd or the maximum point of the voltage command value is exceeded during frequency sweep. It is also possible to take a method of continuing detection. The resonance point detecting means is realized by the control unit 180 set to operate as described above (for example, an operation of executing a resonance point detection program prepared in the control unit 180).

  FIG. 2 is a schematic side view of a vibration type conveying apparatus 10 provided with a vibration source 3 corresponding to the piezoelectric element 3, FIG. 2A is a schematic front view of this embodiment, and FIG. 2B is this embodiment. It is a schematic plan view which abbreviate | omits and shows the conveyance body.

  The vibration type conveying apparatus 10 of the present embodiment includes a base 1, a carrier 2 disposed above the base 1, a vibration source 3 for vibrating the carrier 2, and a vibration source 3. On the other side part (upper end) of the coupling member 4 connected to one side part (lower end), the first elastic support body 5 connected between the carrier 2 and the coupling member 4, and the vibration generating source 3 An inertial body 6 connected as a free end and a second elastic support 7 coupled between the coupling member 4 and the base 1 are provided. The base 1 includes a support plate 1A disposed on the installation surface, and a mounting plate 1B fixed on the support plate 1A and the second elastic support 7 fixed through bolts or the like. Yes.

  The transport body 2 has an attachment material 2A fixed to the first elastic support body 5 via bolts and the like, and a transport material 2B fixed on the attachment material 2A. Groove-shaped tracks are formed. The track extends in the left-right direction in FIG. 2 and holds the conveyed object (not shown), and the vibration S3 transmitted from the vibration generating source 3 described later causes the conveyed object to be in the direction indicated by the arrow FD (hereinafter simply referred to as “conveying direction”). FD ")).

  When the vibration generating source 3 is composed of the above-described piezoelectric element, the piezoelectric type vibration source (piezoelectric driving body) including the piezoelectric element specifically has a piezoelectric layer formed on both the front and back surfaces of the elastic plate. The piezoelectric layer has a bimorph type structure configured to bend by applying a predetermined voltage to the piezoelectric layer. Of course, it may be a unimorph type structure in which a piezoelectric layer is formed only on one side of the elastic plate. These piezoelectric vibration sources bend and vibrate at a frequency corresponding to the frequency by supplying AC power having a predetermined frequency from the outside.

  In the present embodiment, the two sets of the vibration source 3, the connecting member 4, the first elastic support body 5 and the second elastic support body 7 are respectively provided at two positions before and after being separated along the conveyance direction FD. Is provided. That is, the transport body 2 is elastically supported by the first elastic support body 5 and the second elastic support body 7 at two locations in the front and rear. Further, the vibration source 3 arranged in the front is arranged behind the first elastic support body 5 in the front, and further connected to the inertia body 6 arranged in the rear, and the vibration source 3 arranged in the rear is It arrange | positions ahead of the back 1st elastic support body 5, and is further connected to the inertia body 6 arrange | positioned ahead. That is, the inertial body 6 is arranged in the middle of the two sets of vibration generating sources 3 in the front-rear direction, and the two sets of vibration generating sources 3 are connected together to the common inertial body 6.

  The inertial body 6 has an inertial plate 6A connected to the vibration source 3 and an inertial block 6B fixed to the inertial plate 6A, and the inertial block 6B is suspended below the inertial plate 6A arranged on the upper part. It has a fixed structure. The inertia plate 6A is disposed immediately adjacent to the conveyance body 2, and the inertia block 6B is provided so as to protrude downward from the inertia plate 6A so as to overlap the same height range as the vibration generating source 3.

  Both the first elastic support 5 and the second elastic support 7 are plate-like elastic bodies, for example, leaf springs. The first elastic support 5 and the second elastic support 7 are arranged along a common straight line when viewed from the side. As a result, both elastic supports have support characteristics that are similar to those of a single plate-like elastic body between the base 1 and the carrier 2. That is, if the first elastic support 5 and the second elastic support 7 are provided at positions shifted in the front-rear direction, the direction is different from the original vibration direction S1 orthogonal to the posture of the vibration source 3. , Unnecessary vibration modes (for example, vibration modes swinging in the vertical direction) are generated, which may adversely affect the transport characteristics of the transport body 2, as described above. Is arranged along a common straight line, generation of unnecessary vibration modes can be suppressed.

  The common straight line is configured to be parallel to the extending direction of the vibration source 3. As a result, it is possible to efficiently transmit the bending vibration in the direction orthogonal to the extending direction of the vibration generating source 3 (the direction along the plate surface) to the first elastic support body 5 and efficiently vibrate the transport body 2. Can be made. In the present embodiment, by giving vibration S3 in a direction slightly tilted in the vertical direction with respect to the horizontal direction as indicated by the illustrated arrow to the transport body 2, a transport object (not shown) on the transport body 2 is transported in the direction of transport. It is comprised so that it can convey along FD. Therefore, in order to efficiently transmit such vibration, the vibration generating source 3 is set to a posture extending slightly in the front-rear direction with respect to the vertical direction, and the first elastic support 5 and the first The second elastic support 7 is configured to extend in a direction parallel to the vibration source 3.

  Furthermore, since the lower end of the vibration generating source 3 is connected to the connecting member 4 and the upper end of the vibration generating source 3 is connected to the inertial body 6, the inertial body 6 can be easily brought close to the transport body 2, Moments generated by the carrier 2 and the inertial body 6 that vibrate in opposite phases can be reduced, and unnecessary vibration modes can be suppressed. Further, since the inertial body 6 (particularly the inertial block 6B) is arranged so as to overlap the height range of the vibration generating source 3, even if the mass and volume of the inertial body 6 are increased, the device 10 is moved in the height direction. It can be configured compactly.

  In the apparatus 10 configured as described above, when AC vibration is applied to the vibration generation source 3 and bending vibration is generated, the connecting member 4 and the inertial body 6 are bent on the vibration generation source 3 on both sides of the vibration generation source 3. Vibrate in the direction. The vibration S1 of the connecting member 4 is amplified by the first elastic support body 5 and the second elastic support body 7 with the base 1 as a fulcrum, and causes the transport body 2 to generate vibration S3. In addition, a vibration S2 having a vibration phase opposite to that of the connecting member 4 is generated in the inertial body 6 that is a free end.

  In the present embodiment, the vibration generating source 3, the connecting member 4, the first elastic support body 5, the inertial body 6, and the second elastic support body 7 (in the illustrated example, the vibration generating source 3, the connecting member 4, the first elastic support body 6). The elastic support body 5 and the second elastic support body 6 are provided in a pair before and after the transport direction FD.) Corresponds to an excitation mechanism for vibrating the transport body 2. Further, the above-described voltage Vs (output of the inverter 130) corresponds to the drive signal (see FIG. 1) of the vibration mechanism.

  In the present embodiment, as shown in FIG. 1, the voltage Vs (drive signal for the excitation mechanism) at both ends is detected by a detection transformer 170 as voltage detection means, and the output (detection signal) E of this detection transformer 170 is suction controlled. It is introduced into the suction control circuit 210 as means. The suction control circuit 210 outputs a suction control signal F. The suction control signal F is supplied to the suction drive circuit 220, and the drive signal G from the suction drive circuit 220 drives the suction operation valve 230 operated by, for example, a piezoelectric actuator. Here, the suction drive circuit 220 and the suction operation valve 230 correspond to the above suction operation means. The suction actuating valve 230 is not particularly limited as long as the airflow and pressure can be intermittently switched, but in the illustrated example, the suction actuating valve 230 is configured by a piezoelectric valve that operates using the piezoelectric element 231 as a valve body in order to ensure high-speed response. The

  One end of the suction operation valve 230 is connected to a suction device (exhaust device) 240 such as a vacuum pump or an ejector via a suction pipe 241. The other end of the suction operation valve 230 is connected to the suction air passage 2d. The suction pipe 241 and the suction ventilation path 2d constitute the suction path described above. The suction air passage 2d opens to the transport path 2a provided in the transport body 2, and constitutes a suction port 2e. By the operation of the suction operation valve 230, the suction action (presence / absence or increase / decrease) of the suction device 240 is controlled at the suction port 2e.

  The suction control circuit 210 sets the phase value Ph and the operating width Wg based on the detection signal E and generates the suction control signal F. FIG. 4 is a graph showing the relationship between the detection signal E and the suction control signal F. In the illustrated example, the detection signal E is a sine wave having a frequency f = 1 / T (T is a period), but the waveform is not particularly limited. The detection signal E indicates the amplitude of the transport body 2, the potential drop period is the forward period Ta in which the transport body 2 is moving forward in the transport direction FD, and the potential rise period is the transport direction FD of the transport body 2. Is a retreat period Tb retreating in the opposite direction. In general, the vibration of the carrier 2 takes the maximum value of the forward speed and the backward speed at the intermediate point (the origin or zero cross point described later) between the forward period Ta and the backward period Tb, and the carrier 2 is at the front end position and the rear end position of the vibration. It becomes 0 when there is.

  Further, the suction control signal F has a rising point shifted by a reference time difference tph (phase difference θph = tph / T) on the minus side with respect to the origin (zero cross point) t0 where the detection signal E shifts from negative to positive. The pulse width is a rectangular pulse having a period width twg (phase width θwg = twg / T), but the waveform is not particularly limited. In the suction control signal F, a suction control period from the rising point before the origin t0 to the falling point after the origin t0 is set by the rectangular pulse. In the illustrated example, the reference time point of the phase point is the origin t0, but the reference time point is not particularly limited, and the time point when the carrier 2 is at the front end position (the time point when the detection signal E is minimal) or the carrier body 2 May be a time point at which the detection signal E is at the rear end position (a time point when the detection signal E becomes maximum).

  When the suction control signal F is input to the suction drive circuit 220, the suction drive circuit 220 outputs a drive signal G corresponding to the suction control signal F. In response to the drive signal G, the suction operation valve 230 As shown in the open / closed state H, the suction operation valve 230 is opened and suction is performed in the suction operation period corresponding to the suction control period. As shown by the suction force I, the operation of the suction operation valve 230 forms a suction period Tc in which suction force is generated at the suction port 2e corresponding to the operation period (or the suction force increases). Note that the illustrated suction force I indicates a change of the suction force in a state where the suction port 2e is closed for convenience of explanation, and does not indicate the measurement pressure itself at the actual opening position of the suction port 2e. Absent.

  In the case of the present embodiment, the suction period Tc is formed every vibration period T. Further, a non-suction period Td is provided in which the suction force stops (or the suction force decreases) every vibration cycle T. The suction period Tc and the non-suction period Td are determined based on the presence or absence of a suction force that can substantially act on the transport speed of the transported object PT. A mode that cannot be divided into two types may be used. Of the suction period Tc, the suction port 2e is traversed by the relationship between the forward suction time Tca that is a time corresponding to the forward period Ta of the carrier 2 and the reverse suction time Tcb that is a time corresponding to the reverse period Tb. The acceleration / deceleration state of the conveyed product PT is determined.

  The setting of the acceleration / deceleration state of the conveyed product PT is determined by the phase adjustment unit 211 and the time adjustment unit 212 provided in the suction control circuit 210. The phase adjustment unit 211 adjusts the phase of the suction control signal F (specifically, the reference time difference tph or the phase difference θph) by external input (including a case where a manual operation is received) or automatically. The time adjustment unit 212 adjusts the period width twg or the phase width θwg) of the suction control signal F by an external input (including a case where a manual operation is received) or automatically.

  The operation timing of the suction operation valve 230 constituting the suction operation means is determined so that the time lag of the operation and the suction force of the suction operation means are realized in order to realize the suction period Tc and the non-suction period Td having the desired length and phase. Control may be performed at an appropriate timing in consideration of responsiveness. In the illustrated example, the suction period Tc is set before and after the time point so as to include the time point when the transport body 2 is at the rear end position of the vibration. On the other hand, as shown by a dotted line in FIG. 4, the suction period Tc can be set before and after the time point so as to include the time point when the transport body 2 is at the front end position of the vibration. Thus, when the suction period Tc is set to include any of the above-mentioned points in time, both the time part corresponding to the forward period Ta and the time part corresponding to the backward period Tb are included in the suction period Tc. The selection of an acceleration mode and a deceleration mode, which will be described later, or the degree of acceleration / deceleration in the acceleration mode or the deceleration mode can be adjusted in detail and easily by changing the phase of the suction period Tc. Further, even when a certain length of the suction period Tc is secured (even if the period is not shortened), at least a part of the suction period Tc corresponds to the forward period Ta, or the suction period Tc Is prevented from occupying most of the reverse period Tb, so that it is possible to easily prevent the decelerating action from becoming excessive and the conveyed object PT from stopping. However, in the present invention, the case where the conveyed product PT is stopped by controlling the suction force is not excluded.

  Which of the acceleration mode and the deceleration mode is used to select the mode in which the suction period Tc includes the time point when the transport body 2 is at the front end position of vibration or the mode including the time point at the rear end position is selected. Alternatively, it is determined according to various conditions such as whether the conveyance speed of the conveyed product PT is high or low. However, the suction period Tc may be set so as to include both the time point at which the transport body 2 is at the front end position and the time point at the rear end position, and conversely, the suction period Tc is set not to include both time points. It doesn't matter. In the latter case, if the suction period Tc is provided only in one of the forward period Ta and the reverse period Tb and not provided in the other, only one of the acceleration action and the deceleration action is applied to the conveyed object PT. Can affect. As described above, the vibration speed of the transport body 2 is maximum at the intermediate point, but the stress received by the transported object PT when the transport body 2 moves forward or backward is increased during acceleration from the rear end position or the front end position (at the intermediate point). The suction period Tc includes a time point corresponding to the front end position or the rear end position of the transport body 2 from the viewpoint of increasing the influence on the transport state (transport speed) of the transported object PT. It is effective.

  FIGS. 5 and 6 schematically illustrate the movement modes of the acceleration mode and the deceleration mode of the conveyance object PT on the conveyance path 2a formed in the conveyance body 2 when the control method of the present embodiment is used for the separation process of the conveyance object. FIG. As shown in FIG. 5, when the conveyed product PT is accelerated in the acceleration region around the suction port 2 e by receiving the suction force from the suction port 2 e during the forward period, it is pulled forward from the subsequent conveyed product. As a result, a gap CL is generated between the front and rear conveyed items. Thereafter, the conveyance speed of the conveyed product PT is gradually reduced, and the interval CL decreases. A certain transported object is spaced from the preceding and following transported objects, and an inspection position is provided in the separated separation area to obstruct the certain transported object PT from the preceding and following transported objects. Can be inspected. As will be described later, the separation action of the conveyed product PT in the acceleration mode based on the suction force has an advantage that it does not easily affect the subsequent conveyance object, unlike the separation action by the conventional stop or deceleration. Therefore, not only the suction force control method based on the timing synchronized with the vibration cycle according to the present invention, but also a method of accelerating and separating by the suction force provided from the suction port 2e is effective.

  On the other hand, as shown in FIG. 6, when the conveyed product PT is decelerated in the deceleration region around the suction port 2e by receiving the suction force from the suction port 2e during the retreat period, An interval CL occurs. Also in this case, the inspection position is set in a certain separation region. The separation action of the conveyed product PT in the deceleration mode based on such a suction force is in common with the conventional method. However, in the present invention, the suction force is controlled at a timing synchronized with the vibration cycle of the carrier 2. There is an advantage that the action of the suction force on the transported object PT can be reduced from becoming unstable due to fluctuations in the timing relationship with the vibration period.

  7A to 7C are cross-sectional views showing a cross section orthogonal to the transport direction FD of the transport path 2a. In the example of FIGS. 7A and 7B, the transport path 2a is composed of two transport surfaces 2b and 2c that intersect and cross each other, and the suction ventilation path 2d opens on one of the tilted transport surfaces. The suction port 2e is provided. In the example of FIG. 7A, the suction port 2e is provided on the transport surface 2c that is steeper than the transport surface 2b. In the example of FIG. 7B, the suction port 2e is provided on the transport surface 2b that is gentler than the transport surface 2c. Is provided. In the example of FIG. 7C, the transport path 2a is constituted by a horizontal transport surface 2b and vertical transport surfaces (which may be inclined) 2c on both sides thereof, and the suction vent path 2d is formed. A suction port 2e is provided in the transport surface 2b. 7C, the suction port 2e may be formed by opening the suction path 2d on the transport surface 2c. Since the suction port 2e is provided on the transport surface of the transport path 2a as described above, as shown in FIG. 5 and FIG. 6, the process in which the transport object PT moves in the transport direction FD along the transport path 5a. Therefore, the conveyed product PT always passes by the side of the suction port 2a.

  FIG. 8 is an enlarged view when the suction port 2e and the inspection position arranged on the downstream side thereof are provided in part of the spiral conveyance path of the bowl-type parts feeder. Here, the conveyed product PT is a rectangular parallelepiped component, and the suction port 2e has an opening length La smaller than a length Lo along the conveying direction of the conveyed product PT and is orthogonal to the conveying direction of the conveyed product PT. A rectangular opening shape having an opening width Wa smaller than the width in the direction to be provided is provided. By making the opening shape of the suction port 2e rectangular, it is possible to reduce ventilation resistance or pressure loss compared to the case where the opening shape is a circle having the same diameter as the short side, and therefore suction applied to the conveyed object PT. It is possible to increase the strength of the force or the changing speed of the suction force. As illustrated, the rectangular opening shape of the suction port 2e includes two opposite sides parallel to the transport direction FD and two opposite sides orthogonal to the transport direction FD. Here, the opening length La is preferably ½ or less of the length Lo. According to this, since the ratio of La / Lo can be reduced, it is possible to ensure a long period during which the conveyed product PT covers the entire suction port 2e when the conveyed product PT crosses the suction port 2e. Since it becomes easy to configure so that the vibration period T (preferably a plurality of vibration periods) is included in the period, it is possible to reliably apply the suction force to the conveyed object PT. However, if the opening length La is too small, the suction area is reduced. Therefore, it is desirable to set the opening length La so as to ensure a necessary suction force according to the relationship between the transport speed of the transported object PT and the vibration cycle. . Further, as shown in the figure, the opening length La is smaller than the opening width Wa, and when La <Wa is established, it is possible to cover the entire suction port 2e while suppressing a decrease in the suction area (opening area of the suction port 2e). Since the position range in the conveyance direction of the conveyed product PT can be expanded, the acceleration / deceleration region (acceleration / deceleration period) for the conveyed product PT can be increased, or the vibration period and the conveyance position of the conveyed product PT can be increased. Even if the relationship changes, a suction force can be reliably exerted on the conveyed product PT, so that a stable control mode (separation action) can be obtained. Further, it is possible to reduce the influence of the suction force with respect to other transported objects before and after the transported object PT in the transport direction.

  On the downstream side of the suction port 2e, a slit-like detection region 3a of a detector (not shown) (for example, an optical sensor) is provided, and a detection signal is output when the front end of the conveyed object PT hits the detection region 3a. It has become. Further, an inspection device (not shown) for inspecting the conveyed product PT in the inspection range (inspection position) 4a when receiving this detection signal is provided. This inspection apparatus inspects the transported object PT in the inspection range 4a by, for example, optical means (photographing of images, measurement of reflectance, etc.), and the quality of the transported object PT itself and the quality of the posture (orientation). Etc. are discriminated. If the inspection result is good, the conveyed product PT is directly conveyed downstream on the conveyance path 2a, and if the inspection result is negative, compressed air or the like is sent from the air flow outlet 5a opened on the upper part of the conveyance path 2a. By blowing the airflow onto the conveyed product PT, the conveyed product PT is excluded from the conveyance path 2a at substantially the same position as the inspection range 4a. For example, in the case of a bowl-type transport body, the transported material thus removed is returned to the inner bottom (upstream end).

  FIG. 9 is a graph showing measurement results when the control mode of the acceleration mode is set when the suction force of the suction port 2e is actually changed in synchronization with the vibration cycle of the transport body 2 on the transport path 2a. is there. Here, the uppermost control graph shows the timing of the control signal (in the illustrated example, the duty ratio is 1 but is not particularly limited as shown in FIG. 4), and the second amplitude graph is the detected amplitude of the carrier 2. , The third pressure graph shows measured data of pressure in the vicinity of the suction port 2e (position in the suction air passage 2d closer to the suction port 2e than the suction operation valve 230). Here, when the control signal is 0, the suction force is generated (increased), and when the control signal is 1, the suction valve 230 is controlled so that the suction force stops (decreases). In addition, the time when the amplitude graph takes the maximum value is the time when the carrier 2 is at the rear end position, and the time when the amplitude graph takes the minimum value is the time when the carrier 2 is at the front end position. Therefore, the period during which the amplitude graph is falling is the forward period Ta, and the period during which the amplitude graph is rising is the backward period Tb. Further, in the pressure graph, the range in which the conveyed product PT is actually close to the suction port 2e and the actual suction force is generated is indicated by hatching. Even within this range, the pressure (negative pressure, that is, the suction force) increases or decreases as shown in the pressure graph, so that the acceleration / deceleration action by the suction force is also the vertical length (or unit time) of the hatched region. Increase or decrease according to the size of the area in the width.

  In this control mode of the acceleration mode, the phase θa at the time corresponding to the suction start timing of the control signal is shifted 90 degrees before the start time of the forward period Ta, thereby actually generating the suction force at the suction port 2e. The suction period Tc is set before and after the time point so as to include the time point when the transport body 2 is at the front end position of the vibration. The suction period Tc is set to be long in the forward period Ta and short in the reverse period Tb. That is, the above-described forward suction time Tca is longer than the backward suction time Tcb, and the control is performed at the timing when Tca> Tcb is satisfied. In this way, since the suction force is mainly given to the transported object PT while the transporting body 2 is moving forward, the transporting object PT is attracted to the suction port 2e to a speed close to the forward speed of the transporting body 2. Accelerated. However, in this acceleration mode, the transport speed on the upstream side of the suction port 2e of the transported object PT needs to be somewhat lower than the forward speed of the transport body 2 in order to sufficiently obtain the interval CL necessary for separation. There is.

  In this acceleration mode, as shown in FIG. 5, since the transported object PT is accelerated and a gap CL is provided between the transported object PT and the subsequent transported object, there is no possibility of reducing the transport speed of the subsequent transported object. It is not affected by the pushing force from the conveyed product. Here, in the pressure graph, it can be seen that the suction port 2e is closed only when the conveyed product PT crosses the suction port 2e, so that the pressure is reduced and the suction force is exerted on the conveyed product PT. When the conveyed product PT does not exist in the vicinity of the mouth 2e, the suction pressure 2e is not closed, so that the measurement pressure does not decrease. In the illustrated example, it can be understood that one conveyed object PT is accelerated while approaching the vicinity of the suction port 2e and receiving a suction force during approximately 4.5 cycles (4.5 T).

  FIG. 10 is a graph showing the measurement results when the control mode of the deceleration mode is set when the suction force of the suction port 2e is actually changed in synchronization with the vibration cycle of the transport body 2 on the transport path 2a. is there. Here, the control graph, the amplitude graph, and the pressure graph are the same as those in FIG. In this deceleration mode, by delaying the phase θa at the time corresponding to the suction start timing of the control signal by Δθ = 50 degrees from the case of FIG. 9, the suction period Tc becomes longer in the reverse period Tb than in the forward period Ta. It is set as follows. That is, the above-described reverse suction time Tcb is substantially equal to or longer than the forward suction time Tca, and Tcb to Tca or Tcb> Tca is established. In this case, since the influence on the conveyance speed of the conveyed object PT is basically larger at the time of retreat than at the time of advance, almost no acceleration action is obtained at the time of suction at the time of advance, whereas at the time of suction at the time of retreat. Since the decelerating action surely occurs, the conveyed product PT is attracted to the reverse suction port 2e and decelerated.

  In this deceleration mode, as shown in FIG. 6, the transport body 2 is separated from the forward transported object by the deceleration, so that an interval is generated, and therefore the transport speed on the upstream side of the suction port 2 e of the transported object PT is relatively high. However, the separation effect can be obtained without any trouble. Further, the deceleration action due to the suction force occurs only in the reverse period Tb for each vibration cycle of the transport body 2, and the reverse suction time Tcb for giving the deceleration action can be arbitrarily set within the reverse period Tb and the forward time giving the acceleration action Since the suction time Tca is also present, there is little risk of the transported object PT being completely stopped, and a stable deceleration operation can be obtained.

  Here, as in the case of FIG. 9, in the above pressure graph, the suction port 2e is closed only when the conveyed product PT crosses the suction port 2e, so that the pressure is reduced and the suction force is exerted on the conveyed product PT. However, when the conveyed product PT does not exist in the vicinity of the suction port 2e, the suction port 2e is not closed, so that the measurement pressure does not decrease. In the illustrated example, it can be understood that one conveyed product PT is decelerated while approaching the vicinity of the suction port 2e and receiving a suction force in approximately six cycles (6T).

  In this embodiment, since the suction period Tc set at the timing synchronized with the vibration cycle is provided for each vibration cycle of the transport body 2, the suction force controlled in timing for each vibration cycle is reliably exerted on the transported object PT. be able to. In particular, providing only one suction period Tc within one vibration period T as in the illustrated example ensures easy control of the suction force even when the suction force response is poor or the vibration frequency is high. It is preferable in that it can be performed. In addition, by adjusting the phase by a control signal synchronized with the vibration period and setting the time distribution corresponding to the forward period Ta and the reverse period Tb in one suction period Tc, or by setting the uneven distribution mode to either, The degree of increase / decrease in acceleration / deceleration action or acceleration / deceleration action on the conveyed object PT can be adjusted in more detail.

In the present embodiment, since the suction port 2e has a rectangular opening shape, it is possible to reduce ventilation resistance or pressure loss compared to a circular opening shape without corners, and therefore suction force applied to the conveyed product PT. It is possible to increase the strength or the changing speed of the suction force. The reason for this is that if there are corners in the opening shape, the entire length of the opening edge will increase during the process of returning to atmospheric pressure, improving the inflow efficiency of the atmosphere, and increasing the pressure difference around the opening center will disrupt the airflow. For this reason, the cause such as the rapid loss of suction power can be considered. In addition, since the pressure gradient from the vicinity of the center of each side of the opening shape toward the center of the opening shape increases and a difference in pressure gradient occurs around the center of the opening shape, this difference leads to the center from the center of the side of the opening shape. Since an early air flow is generated, the surrounding air is also engulfed by this early air flow, so that the vicinity of the opening returns to the atmospheric pressure at an early stage, and in some cases becomes a positive pressure with respect to the atmospheric pressure. A decrease may also occur .

  In order to efficiently apply the suction force to the conveyed product, the suction port 2e that opens on the conveyance surface of the conveyance path 2a as described above has an opening area that is larger than the projection surface with respect to the conveyance surface in the conveyance posture of the conveyance object PT. Is preferably reduced. At this time, the transported object PT on the transport path moves to some extent due to vibration, so that the suction port 2e is not easily protruded from the projection surface of the transported object PT, while the margin of the suction port 2e with respect to the projection surface is secured. In order to suppress a decrease in the opening area that causes a decrease in force, the orientation of the opening shape is aligned with the projection plane, and there are two opposite sides parallel to the conveyance direction FD and two opposite sides perpendicular to the conveyance direction FD. A rectangular opening shape is preferred. For example, when a predetermined margin is ensured between the opening shape of the suction port 2e and the projection surface, when the opening shape is rectangular, the gap between the conveyed object PT and the conveying surface is larger than when the opening shape is circular. Since the average distance from the outer surface of the conveyed product PT to the opening edge of the suction port 2e can be shortened, the speed of the pressure increase due to the introduction of outside air through the gap near the opening at the time of suction stop is increased and quickly The suction force can be reduced.

  Note that the vibratory conveyance device of the present invention is not limited to the above-described illustrated examples, and it is needless to say that various changes can be made without departing from the gist of the present invention. For example, in the above-described embodiment, one suction period Tc and the other non-suction period Td are provided for each vibration period T of the transport body 2, and the correspondence between the phase of the suction period Tc and the forward period Ta and the backward period Tb is provided. Although the conveyed object PT is accelerated / decelerated by setting the relationship, the length of the conveyed object PT, the opening length of the suction port 2e, as long as the presence / absence of the suction force and the timing of increase / decrease are synchronized with the vibration cycle, One suction period Tc may be provided for each of a plurality of periods of vibration according to the conveyance speed of the conveyed object PT on the upstream side, the vibration frequency of the conveyance body 2, or the like. The suction period Tc may be provided. Moreover, although the case where the transported object PT is separated in the transport direction is shown in the actual measurement data, it can be used in various cases where the transport speed of the transported object PT is controlled and adjusted. In this case, a plurality of suction ports may be arranged in the transport direction, and increase, decrease, increase / decrease, etc. of the transport speed may be realized individually or continuously at a plurality of locations.

  In the present embodiment, as an aspect of exerting the deceleration action or the acceleration action, a suction force is unconditionally generated at the suction port 2e for each vibration period T. However, the transported object PT is placed at a predetermined position on the transport path 2a. Whether to generate a suction force synchronized with the vibration cycle T or to change (switch) the generation timing of the suction force with respect to the vibration cycle T according to the detection signal of the detector. You may make it decide whether or not.

  Furthermore, in the present embodiment, the description has mainly been given of the case where either the deceleration action or the acceleration action is exerted on the conveyed product PT. However, the acceleration action is exerted on the same conveyed object PT after the deceleration action is exerted. Further, the acceleration action may be applied and then the deceleration action may be applied. In this case, when the period in which the conveyed object PT crosses the suction port 2e extends over a plurality of vibration periods, the reverse period for applying the deceleration action and the forward period for applying the acceleration action are not limited to periods within the same vibration period. Since the period within the vibration cycle can also be set, the deceleration action and the acceleration action can be realized for the same conveyed object PT by one suction port 2e. On the other hand, a plurality of suction ports 2e may be arranged in the transport direction, and a suction port 2e that provides a deceleration action and a suction port 2e that provides an acceleration action may be provided separately.

DESCRIPTION OF SYMBOLS 10 ... Vibration type conveying apparatus, 2 ... Conveyance body, 3 ... Vibration generating source, 2a ... Conveyance path, 2b, 2c ... Conveyance surface, 2d ... Suction air passage, 2e ... Suction port, 210 ... Suction control circuit, 220 ... Suction Drive circuit, 230 ... suction operation valve, 240 ... suction device, T ... vibration period, Ta ... forward period, Tb ... reverse period, Tc ... suction period, Td ... non-suction period, Tca ... forward suction time, Tcb ... reverse Suction time, Lo ... length, La ... opening length

Claims (6)

In the conveyance method of the conveyance object which conveys a substantially rectangular parallelepiped conveyance object by a vibration type conveyance device,
The vibratory transfer device is
A transport body provided with a transport path along which a transport object is transported along a transport surface that supports and guides the transport object;
An excitation mechanism that vibrates the transport body in the transport direction in a mode in which the transport object is transported in the transport direction on the transport path;
A suction port having a rectangular opening shape opening in the transport surface of the transport path;
A suction actuating means configured to switch the presence or absence of a suction force at the suction port, or configured to increase or decrease the suction force;
Comprising
The opening shape has two opposite sides parallel to the conveying direction and two opposite sides perpendicular to the conveying direction, and has an opening length smaller than the length along the conveying direction of the conveyed object, and It has an opening width smaller than the width in the direction orthogonal to the conveyance direction of the conveyed product,
The opening length is ½ or less of the length along the transport direction of the transported object,
The suction actuating means is controlled so that the switching or increase / decrease of the presence / absence of the suction force occurs in synchronization with the vibration cycle of the transport body by the vibration mechanism, and the presence / absence of the suction force for one transported object. A method for conveying a conveyed product, wherein the suction force is applied over a plurality of times of switching or increasing / decreasing.   2. The method for transporting a transported object according to claim 1, wherein the suction actuating unit is controlled so that switching or increasing / decreasing of the presence / absence of the suction force occurs at each vibration cycle.   The method for transporting a conveyed product according to claim 1, wherein the opening length is smaller than the opening width. Whether the suction force is switched or increased / decreased, the forward suction time (Tca) in which the suction force is applied to the transport object when the transport body moves forward within the vibration period is the transport time when the transport body moves backward. By controlling so as to be longer than the reverse suction time (Tcb) in which the suction force is applied to the object, the object is accelerated by the suction force when the object crosses the suction port. The conveyance method of the conveyed product as described in any one of Claims 1 thru | or 3 characterized by the above-mentioned. Whether the suction force is switched or increased / decreased, the reverse suction time (Tcb) during which the suction force is applied to the transport object when the transport body is retracted within the vibration period is the transport time when the transport body is moving forward. By controlling so that the suction time (Tca) at which the suction force is applied to an object is equal to or longer than the suction time (Tca) during advancement, the object is decelerated by the suction force when the object crosses the suction port. The conveyance method of the conveyed product as described in any one of Claims 1 thru | or 3 characterized by the above-mentioned. A detection area (3a) of the detector for the conveyed object is provided on the downstream side of the suction port of the conveyance path, and a detection signal of the detector is output when the conveyed object reaches the detection area (3a). The said conveyed product in the inspection range (4a) of an inspection apparatus is test | inspected by the said inspection apparatus by this , The conveying method of the conveyed article as described in any one of Claim 1 thru | or 5 characterized by the above-mentioned.

Images