FR2880700A1 - Operator hand presence detecting device for control handle of e.g. public works vehicle, has processing unit to find presence from electric signals of electrodes formed in form of coating to be applied on wall of half-shells of handle - Google Patents

Abstract

The device has a processing unit (8), connected to conducting measurement electrodes (4, 5, 6, 7), to determine the presence or absence of hand of an operator on a control handle from electric signals coming from the electrodes. The electrodes are formed partially in the form of coating to be applied on an inner wall of a part of half-shells (9, 10) of the handle, where the coating shape is complementary to that of the wall after application. An independent claim is also included for a control handle comprising an operator hand presence detecting device.

Description

The present invention relates to a device for detecting the presence of

  the hand of the operator on a control handle intended in particular for use in a public works machine, agricultural machine, or a handling machine.

  The realization of a presence detection of the operator, corresponding to the gripping of the handle by the operator, is imposed by the manufacturer of the machine or the legislation, in the case of so-called security functions that can be fulfilled by the control handle and which require control from the operator.

  The control of the movement of an organ of a public works machine may constitute such a function, for example.

  It is known to perform the presence detection of the operator by including a trigger in the handle, the trigger controlling an electrical switch. Thus, the operator actuates the trigger and the electric switch by tightening the handle.

  This first solution allows presence detection. However, it requires an effort on the part of the operator, who must maintain the grip of the handle. It is also difficult to maintain the watertightness of the handle, because the trigger is a moving part relative to the body of the handle. It should be noted that the tightness of the handle is particularly important for cabs of public machines intended to be washed with water, or subjected to the weather, in the case of open cabins.

  In addition, this solution does not allow latitude in the positioning of the hand on the handle, because the trigger imposes this positioning.

  According to a second known embodiment, outer electrodes made of metal sheets are included in the shells of the handle, these electrodes forming between them one or more capacitors. These abilities vary depending on whether there is presence of the operator's hand. This capacity is connected to an electronic circuit which allows or prohibits the realization of the security function according to the presence or absence of the hand.

  This second solution allows presence detection. However, the placement of the electrodes on the handle is difficult. Indeed, the surfaces of the parts that make up the handles are left surfaces on which it is difficult to fix sheet electrodes.

  Consequently, only electrodes of limited size can be used, these electrodes having a low sensitivity, a limited detection zone, and measurements strongly disturbed by external elements other than the hand of the operator.

  In addition, their mounting cost on the handle is important and they affect the external appearance of the handle.

  The present invention aims to overcome the disadvantages mentioned above by providing a position detection device requiring no effort on the part of the operator, allowing the seal of the handle, and allowing adaptation to the shape of the handle.

  For this purpose, the subject of the present invention is a device for detecting the presence of the operator's hand on a control handle intended in particular for use in a public works machine, a farming machine or a handling machine, comprising a shell defining an interior space, comprising: - at least one measuring conductive electrode, comprising a conductive material, and forming with reference at least one capacitor, and - processing means connected to the electrodes making it possible to determine the presence or the absence of the hand of the operator from the electrical signals from the electrodes, characterized in that at least one of the electrodes is at least partly in the form of a coating intended to be applied to the inner wall of the part of the shell of the handle, and whose shape is complementary to that of the wall after application.

  These provisions allow the easy installation on a left surface, the watertight because the shell can be completely closed, and do not require a fixing device to provide in the shells constituting the handles, allowing an investment and a small footprint.

  These arrangements also make it possible to increase the surface area of the electrodes and consequently to avoid the use of significant electronic gain, the device thus being less sensitive to external disturbances other than those of the operator's hand.

  According to a first possibility, the conductive material consists of a layer of flexible conductor.

  According to one embodiment, the flexible conductor layer is constituted by a copper film.

  Advantageously, the conductor layer is fixed on a flexible adhesive support, itself intended to be fixed on the inner wall of the shell.

  According to a second possibility, the conductive material is constituted by a coating, made in particular in the form of a conductive paint or by a galvanoplastic deposit applied on the shell.

  Advantageously, the conductive material is covered with an insulating layer.

  This arrangement makes it possible to guarantee the operation of the device, even if the sealing of the hull is no longer ensured, and to prevent problems due to condensation inside the hull.

  According to one embodiment, the insulating layer is constituted by a varnish or a resin.

  According to another possibility, the electrode is constituted by a flexible circuit comprising conductive tracks embedded in an insulating flexible support thus constituting a superposition of a flexible insulating support layer, a metal layer, and an insulating support layer. flexible.

  Advantageously, at least one electrode is multiple, composed of several individual electrodes.

  This arrangement allows to adapt the device to particular shapes of the handle, while maintaining a simple mounting on the handle and a large surface of the electrode.

  According to one embodiment, the device comprises at least a first and a second measurement electrode.

  According to one possibility, the device comprises at least one pair of electrodes comprising a measurement electrode and a reference electrode forming between them a capacitance.

  According to another possibility, the device comprises at least one measurement electrode forming a capacitance with the mass of the machine on which the device and the handle are fixed.

  Advantageously, the processing means make it possible to combine the signals coming from the two measurement electrodes, in order to output a signal indicating the detection when the two measurement electrodes detect a presence, or when at least one of the measurement electrodes detects a presence.

  This arrangement makes it possible to adjust the grip holding requirement to conclude that presence detection is required.

  According to one embodiment, the processing means perform a periodic calibration to take into account changes in the external conditions affecting the detection parameters.

  This arrangement makes it possible to take account of the ambient humidity or the wearing of a glove by the operator.

  Advantageously, the processing means comprises delay means for maintaining the detection signal at a given value of detection or non-detection, during a determined time interval after the change of information from the electrodes.

  This arrangement makes it possible to avoid blocking the safety function when the operator releases the handle for an insignificant period of time, for example to take back the handle in hand, or to unlock the safety function while the operator has simply touched the door. handle inadvertently, without intention to seize it.

  The present invention also relates to a control handle intended in particular for use in a public works machine, agricultural machine or a handling machine, comprising a detection device as described above.

  Advantageously, at least one measuring electrode is located in the shell, at its longitudinal portion.

  According to one embodiment, at least one measuring electrode is disposed in the shell, at the free end of the handle.

  In any case, the invention will be better understood with the aid of the following description, with reference to the appended diagrammatic drawing, representing by way of nonlimiting example, several embodiments of a device and a handle according to the invention.

  Figure 1 shows a handful of construction equipment according to the invention, seen from the outside.

  Figure 2 is a sectional view of the handle of Figure 1 illustrating the position of the processing means, in the form of electronic card, in the mounted state.

  Figure 3 shows a handle of Figure 1 in the disassembled state, the two half-shells of this handle having been separated and revealing the detection device.

  Figure 4 is a detailed view of an electrode, in section along IV-IV of Figure 3, according to a first embodiment.

  Figure 5 is a schematic detail view of the electronic board showing its connections.

  Figure 6 shows the circuit diagram of the components of the electronic card.

  Figure 7 is a detailed view of an electrode, according to a second embodiment.

  Fig. 8 is a detail view of an electrode according to a second embodiment.

  Figure 9 is a schematic detail view of the electronic board, showing its connections, according to a variant of the first embodiment.

  According to a first embodiment shown in FIGS. 1 to 6, a device 2 for detecting the presence of the operator's hand on a control handle 3 intended in particular for use in a public works machine or a machine agricultural, comprises: a first pair and a second pair of electrodes, each pair of electrodes comprising a measuring electrode 4, 5 and a reference electrode 6, 7 connected to the ground, the two coupled electrodes forming a sensor capacitive.

  - Processing means 8, consisting of an electronic card, connected to the electrodes 4, 5, 6, 7 and for determining the presence or absence of the hand of the operator from the electrical signals from the electrodes.

  According to a variant of this first embodiment, the electrodes 4 and 6 on the one hand and 5 and 7 on the other hand, constitute two multiple measurement electrodes, which form a capacitance with the mass of the machine, the coupling being realized through the operator.

  This variant incorporates the elements of the first embodiment, with the exception of the connections of the electronic card, which will be detailed below.

  The handle 3 comprises a shell of insulating material forming an elongate envelope delimiting an interior space, formed by two half-plates 9 and 10 intended to be assembled.

  The handle 3 has an elongate shape having a free end 12 and a fixing end 13 intended to be fixed on a not shown movable support, the movement of the handle on the support for generating control signals to organs to be controlled for perform the safety function.

  At the fixing end 13, the handle has an opening 14 through which conductive wires 15, 16, 17 may pass for: conveying the signals from the processing means 15 and 10 - providing a power supply 16 , 17.

  Each electrode 4, 5, 6, 7 is connected via a conductive wire 18, 19, 20, 21 to the electronic card 8.

  The electrodes 4, 5, 6, 7 are made in the form of a coating comprising a conductive material and are each intended to be fixed on the inner part of a shell 9, 10 forming the handle 3 by adapting to its shape.

  As shown in Figures 1 to 3, all the electrodes 4, 5, 6, 7 are located at the longitudinal portion of the handle, and are formed of an elongated rectangle-shaped coating. Two electrodes forming a pair, or alternatively a multiple electrode, are arranged parallel to the inside of the same half-shell.

  As shown in FIG. 4, in this embodiment, each electrode is constituted by a flexible coating, comprising a flexible conductive material, in the form of a flexible layer of copper 23.

  This flexible copper conductive layer 23 is fixed on a self-adhesive support 24, which makes it possible to fix it on the inner wall of a half-shell 9.

  The copper layer 23 is covered with a varnish 25 to seal.

  Alternatively, the varnish can be replaced by a resin.

  Referring to Figures 5 and 6, we now detail the components of the electronic card 8 and their operation.

  FIG. 5 illustrates the connections of the card 8, in the case of pairs of electrodes each comprising a measuring electrode and a reference electrode.

  The connection of the card 8 comprises: two inputs E1 and E2, intended to connect the conductor wires 18 and 19 respectively connected to the two measuring electrodes 4, 5 of the two pairs of electrodes, - two inputs Elref and E2ref, intended to connect the conductive wires 20 and 21 respectively connected to the two reference electrodes 6, 7 of the two pairs of electrodes, these two inputs being connected directly to the ground, two inputs A1 and A2 intended to be respectively connected to the supply leads 16 and 17, the input A2 being connected to ground, an output O to be connected to the output signal wire 18.

  FIG. 9 illustrates the connections of the card 8, in the case of the variant comprising multiple measuring electrodes forming a capacitance with the mass of the machine.

  The connection of the card 8 comprises in this case: two inputs E1 and E2 intended to connect the conductive wires 18 and 20 on the one hand and 19 and 21 on the other hand respectively connected to the two multiple measurement electrodes 4, 6 on the one hand and 5 and 7 on the other hand, two inputs A1 and A2 intended to be respectively connected to the supply leads 16 and 17, the input A2 being connected to ground, - an output O intended to be connected to the output signal wire 18.

  Figure 6 schematically shows the components of the board 8, connected to the inputs and outputs described above.

  The card 8 includes a chip 26 dedicated to the detection of contact. This may be for example a QT320 type chip from Quantum Research Group Limited or any other equivalent chip.

  The chip makes it possible to carry out the detection according to two channels, which correspond to the two measuring electrodes.

  It outputs for each channel a digital signal indicating whether there is presence detection as a function of detection thresholds that can be set independently for each channel.

  The internal operation of the chip is known and described in the documentation thereof, and therefore will not be repeated in detail here.

  The chip 26 has 8 tabs: - two tabs S1A and S1B, which constitute the inputs of the first channel - two tabs S2A and S2B, which constitute the inputs of the second channel, - a tab OUT1, which constitutes the output of the first channel, providing a signal indicating whether or not there is detection by the first measuring electrode, - a tab OUT2 which constitutes the output of the second channel, providing a signal indicating whether there is detection or not by the second measurement electrode, - two legs Vdd and Vss power supply.

  The supply leg Vdd is connected to: - the feed input Al of the card 8, - to the ground via a capacitor C4.

  The feed leg Vss is connected to the ground.

  The tab S1A is connected: - to the input El of the card 8 via a resistor R3, - to the tab S1B by a capacitor C1, and - to the ground via a capacitor C3 .

  The tab S2A is connected: - to the input E2 of the card 8 via a resistor R4, - to the leg Si B by a capacitor C1.

  The output tabs of the two channels OUT1, OUT2 are connected, respectively by two resistors R1 and R2, to two inputs of a component 27, which makes it possible to carry out an AND or logical OR operation on the two output signals of the first and second channels of the chip to provide the output signal of the board on the output O. This component 27 allows to combine the signals from the two measurement electrodes, in order to output a signal indicating the detection when the two electrodes measuring a presence, or when at least one of the measuring electrodes detects a presence. 10 and

  By way of example, the values of the voltages, capacitors and resistances used may be as follows: Vcc: 4.5 Vf-R1: 1.5k -R2: 1.5k0-R3: 47k0-R4 47kO - Cl: between 2 nF and 100 nF - C2: between 2 nF and 100 nF - C3: 5 pF - C4: 100 nF.

  Preferably, the capacitors implanted on the board are of NOP or COG ceramic type, or of PPS film type or of Y5E and X7R ceramic type.

  The type of circuit described above is particularly suitable for increasing the sensitivity of detection and allowing it through the thickness of the shell forming the handle 3.

  Chip 26 is programmed to be periodically calibrated to account for changes in external conditions affecting the sensing parameters.

  On the other hand, the card 8 comprises unrepresented timing means for maintaining the detection signal at a given value of detection or non-detection, for a determined time interval after the change of information from the electrodes.

  According to a second embodiment, the same elements are repeated, the electrode structure being however different.

  As shown in FIG. 7, in this embodiment, the electrodes consist of a flexible circuit comprising conductive tracks embedded in an insulating flexible support.

  The flexible circuit comprises a superposition of a first layer of flexible insulating support 28, a metal layer 29, and a second layer of flexible insulating support 30, the flexible circuit being able to be fixed on the half-shell by a layer of adhesive 32 .

  According to a third embodiment, the same elements are repeated, the electrode structure being however different.

  As shown in FIG. 8, the coating constituting the electrode comprises a conductive layer constituted by a deposit of material 33, produced in the form of a conductive paint or, alternatively, by a galvanoplastic deposit. This deposit of material can be applied directly on the hull.

  This coating may itself be protected by an insulating layer 34, to ensure sealing.

  Alternatively, a measuring electrode is disposed at the free end of the handle. This arrangement makes it possible to manipulate the handle by not grasping it, but simply by putting one's hand on its end.

  It should be noted that the use of multiple electrodes, composed of several individual electrodes makes it possible to adapt the device to particular shapes of the handle, while maintaining a simple mounting on the handle and a large surface of the electrode as well as incorporated.

  In particular, this arrangement is used when the shell comprises a screw thread 35, as shown in Figures 2 and 3, which does not allow to simply fix a sufficient surface electrode in one part on the shell.

  As is self-evident, the invention is not limited to the preferred embodiments described above, by way of non-limiting examples; it encompasses all the variants in the context of the claims below.

Claims (18)

  1. Device (2) for detecting the presence of the hand of the operator on a control handle (3) intended in particular for use in a public works machine, agricultural machine or handling machine, comprising a hull (9, 10) defining an interior space, comprising: at least one measuring electrode (4, 5, 6, 7) comprising a conductive material and forming with reference at least one capacitor, and - processing means (8) connected to the electrodes (4, 5, 6, 7) for determining the presence or absence of the operator's hand from the electrical signals from the electrodes, characterized in that at least one of the electrodes (4, 5, 6, 7) is made at least partly in the form of a coating, intended to be applied to the inner wall of a part of the shell (9, 10) of the handle, and whose shape is complementary to that of the wall after application.   2. Device according to claim 1, characterized in that the conductive material is constituted by a flexible conductor layer (23).   3. Device according to claim 2, characterized in that the flexible conductor layer (23) is constituted by a copper film.   4. Device according to one of claims 2 and 3, characterized in that the conductor layer (23) is fixed on a flexible adhesive support (24), itself intended to be fixed on the inner wall of the shell ( 9, 10).   5. Device according to claim 1, characterized in that the conductive material is constituted by a material deposit (33), in particular in the form of a conductive paint or by a galvanoplastic deposit applied to the shell (9, 10).   6. Device according to one of claims 1 to 5, characterized in that the conductive material (23, 33) is covered with an insulating layer (25, 28, 34).   7. Device according to claim 6, characterized in that the insulating layer consists of a varnish (25) or a resin.   8. Device according to claim 1, characterized in that the electrode is constituted by a flexible circuit, comprising conductive tracks (29) embedded in a flexible insulating support (30, 28) thus constituting a superposition of a layer of flexible insulating backing (28), a metal layer (29), and a flexible insulating backing layer (30).   9. Device according to one of claims 1 to 8, characterized in that at least one electrode is multiple, composed of several individual electrodes.   10. Device according to one of claims 1 to 9, characterized in that it comprises at least a first (4, 6) and a second (5, 7) measuring electrode.   11. Device according to one of claims 1 to 10, characterized in that it comprises at least one pair of electrodes comprising a measuring electrode (4, 5) and a reference electrode (6, 7) forming between them a capacity.   12. Device according to one of claims 1 to 10, characterized in that it comprises at least one measuring electrode (4, 5, 6, 7) forming a capacity with the mass of the machine on which is fixed the device and the handle.   Device according to one of Claims 10 to 12, characterized in that the processing means (8) make it possible to combine the signals coming from the two measuring electrodes (4, 6, 5, 7) in order to output (0) a signal indicating the detection when the two measuring electrodes detect a presence, or when at least one of the measuring electrodes detects a presence.   14. Device according to one of claims 1 to 13, characterized in that the processing means (8) perform a periodic calibration to take into account changes in the external conditions affecting the detection parameters.   15. Device according to one of claims 1 to 14, characterized in that the processing means (8) comprises timing means for maintaining the detection signal at a given value of detection or non-detection, during an interval determined time after the change of information from the electrodes.   16. Control handle intended in particular for use in a public works machine, a farm machine or a handling machine, comprising a device according to one of claims 1 to 15.   17. Control handle according to claim 16, characterized in that at least one electrode pair is located in the shell (8, 9) at its longitudinal portion.   18. Control handle according to one of claims 16 and 17, characterized in that at least one measuring electrode is disposed in the shell (8, 9) at the free end (12) of the handle .