JP6172651B2 - Electric gripping device - Google Patents

Description

The present invention relates to an electric gripper equipment, in particular, artificial arm or for those who forearm is deficient, such as by cutting, and is preferably applied to the self-help tool for those who gripping function becomes failure.

  For example, the prosthetic hands currently selectable by the forearm amputeer include decorative prostheses, active prostheses, and myoelectric prostheses. The active prosthetic hand is a prosthetic hand that operates the opening and closing of the hook-shaped hand by pulling the cable using the movement of the shoulder on the side opposite to the cut forearm side, and is relatively inexpensive and highly workable. . However, since it is necessary to attach the harness for pulling the cable to the body, there is a problem that the user is restrained and the design of the hook is greatly damaged.

  On the other hand, the myoelectric prosthetic hand has a natural appearance close to that of a human hand, and has a merit that natural operability can be obtained because the finger movement is performed using a myoelectric potential measurable from the forearm as a signal source. Some myoelectric prostheses have three or five finger members and achieve the same movement as that of a healthy person's finger, but the mechanism is complicated and the price increases. Therefore, it is not easy to obtain a myoelectric prosthesis. In addition, since such myoelectric prostheses are generally heavy, there are many amputees who do not get used to the weight even when they are finally obtained and stop using it. Furthermore, the myoelectric prosthesis is based on the premise that the surface electromyogram is sensed by the myoelectric sensor, but the sensing operation may become unstable due to the skin condition of the forearm amputee, for example, perspiration. Also, there are forearm amputees whose surface myoelectric potential is so weak that they cannot withstand sensing, or there are no forearm amputees, and such forearm amputees cannot actually use myoelectric prosthetic hands. .

  These problems become obstacles, and many forearm amputees do not use work prostheses, and currently use decorative prostheses with low functionality.

Japanese Patent Laid-Open No. 11-56885 Japanese Patent Laid-Open No. 10-201782

  The present invention has been made in view of the above problems, and an object of the present invention is to realize a prosthetic hand and a self-helper that are lightweight, inexpensive and excellent in stability while achieving both workability and operability.

Therefore, the present invention is an electric gripping device that can be mounted on the upper forearm,
A non-contact sensor that detects changes in the skin surface that appear as the upper forearm muscle contracts and relaxes;
According to the detected skin surface change, a plurality of finger members capable of taking a closed state in which the tips contact each other and an open state in which the tips are radially open, and a drive source driven by energization are driven. In response, a hand unit having an opening and closing mechanism for displacing the plurality of finger members so as to be in the open state and the closed state;
A pair of proximal end portions for receiving the upper portion of the forearm, facing each other through the opening portion, a pair of distal end portions for supporting the hand unit, facing each other through the opening portion, and the proximal end side An interface unit having an open part continuous from the position to the distal side,
The ingredients example,
The pair of distal end portions are formed with a positional relationship shifted by a predetermined angle in the pronation direction of the forearm to be attached to the pair of proximal end portions .

  ADVANTAGE OF THE INVENTION According to this invention, it can contribute to provision of the prosthetic hand and self-help tool which were lightweight and cheap, and was excellent in stability, making workability and operativity compatible.

It is a perspective view which shows the example of an external appearance structure of the electric prosthetic hand as one Embodiment of this invention electric holding device. It is a schematic diagram shown in the state which mounted | worn the electric prosthesis of FIG. 1 to the forearm part of the forearm defect | deletion person. It is a perspective view which shows embodiment of the interface unit which is a component of the electric prosthesis of FIG. It is a front view of the holding | grip function part of the hand unit which is a component of the electric prosthetic hand of FIG. It is the figure which showed the hand unit from the lower part in the state which removed the cap from some finger members. It is the figure which showed the hand unit from the lower part in the state which removed the front-end | tip part from some finger members. It is the figure shown from the lower part in the state which fractured | ruptured a part of hand unit in order to demonstrate the opening / closing mechanism and opening / closing operation | movement of a finger member. It is the figure shown from the lower part in the state which fractured | ruptured a part of hand unit in order to demonstrate the opening / closing mechanism and opening / closing operation | movement of a finger member. It is the figure shown from the lower part in the state which fractured | ruptured a part of hand unit in order to demonstrate the opening / closing mechanism and opening / closing operation | movement of a finger member. (A) And (b) is the typical side view for demonstrating the bottom view and detection principle which respectively show the external appearance structure of the sensor unit of the form of the photo reflector used as the component of the electric prosthesis of FIG. It is a block diagram which shows the structural example of the control system employable for the electric prosthesis shown in FIG. It is a flowchart which shows an example of the control procedure by the control system of FIG. It is explanatory drawing for demonstrating the aspect of the calibration performed prior to use of an electric prosthetic hand. It is a perspective view which shows the example of an external appearance structure of the self-help tool as other embodiment of this invention electric holding device.

  Hereinafter, the present invention will be described in detail with reference to the drawings. In the following description, an electric gripping device or hand unit for the left forearm is illustrated, but it goes without saying that application to the right forearm is possible by appropriately changing the symmetry. In addition, the “cut end” refers to the rest of the forearm that has been lost due to the cut, but the electric prosthetic hand according to the embodiment shown in FIG. It can be applied to the rest.

(1) Configuration (1-1) Overall Configuration FIG. 1 is a perspective view showing an external configuration example of an electric prosthesis as an embodiment of the electric gripping device of the present invention. The electric prosthetic hand shown in the figure includes an interface unit 100, a hand unit 200, and a support unit 500 for supporting the hand unit 200 on the interface unit 100. The interface unit 100 functions to connect the cut end of the user's left forearm and the hand unit 200. The hand unit 200 includes a plurality of (in this example, three) finger members, a gripping function unit 300 that performs a gripping function, a drive unit 400 that includes a motor and a control unit for driving the gripping function unit 300, and the like. Have The support unit 500 is supported by the support unit 501 that supports the hand unit 200 at the site of the drive unit 400 and the end of the interface unit 100 (the side that is distal from the shoulder) so as to be rotatable about the rotation shaft 541. A supported portion 511.

  FIG. 2 is a schematic diagram showing the electric prosthesis of FIG. 1 mounted on the remaining forearm of the user. As shown in the figure, the electric prosthesis of this example receives the cut end 1 from the open part of the interface unit 100 defined on the base end side (the side proximal to the shoulder), and appropriately surrounds the periphery thereof. It is attached by surrounding with a band member 130. In addition, what is shown with the code | symbol 480 is a wiring member for sending / receiving an electrical signal between the sensor unit mentioned later and the control part incorporated in the drive part 400. FIG.

(1-2) Interface Unit FIG. 3 is a perspective view showing the interface unit 100 according to the present embodiment. The interface unit 100 of this example is a member made of ABS resin formed using, for example, a 3D printer, and has a hollow substantially cylindrical shape with both ends open as a basic shape, and receives a cut end on the base end side, The support unit 500 is supported on the distal side. A pair of opposed substantially U-shaped cutout portions 121O and 121I are formed at the open end on the proximal end side in the distal direction. On the other hand, at the open end on the end side, a pair of opposed substantially U-shaped notches 131O and 131I are shifted relative to the notches 121O and 121I by a predetermined angle in the circumferential direction with respect to the longitudinal axis 100L. And formed toward the base end side. Therefore, the interface unit 100 has a pair of opposed base end portions 123R and 123U and a pair of distal end portions 133R and 133U facing each other with a positional relationship shifted in the circumferential direction. The shift direction is the counterclockwise direction C in FIG. 3, that is, the clockwise (inward) direction as viewed from the user, and the shift angle is an appropriate angle of more than 0 degree and less than 90 degrees. Further, the notches 121O and 131O are connected to each other at the bottom of the U shape via the open portion 101. Therefore, the interface unit 100 is connected to the open end portion on the distal side from the open end portion on the base end side. Until now, it has one continuous open part formed by the cutout part 121O, the open part 101 and the cutout part 131O.

  Because the conventional prosthetic hand is an active prosthetic hand or a myoelectric prosthetic hand, it is necessary to produce a hard socket for inserting the cutting end so that the prosthetic orthosis fits the cutting end over time, The production was time-consuming and expensive. Further, when the socket does not fit, the cut end is easily damaged, and sweat accumulated in the sealed socket causes skin irritation such as rash. On the other hand, the interface unit according to the present embodiment is provided with an open part as described above, so that it is versatile and can be easily mounted flexibly corresponding to a cut end that may have various dimensions. In addition, it is possible to suppress the occurrence of wounds and inflammation.

(1-3) Support angle and palmar dorsiflexion function of the hand unit As described above, by including the end side portions 133R and 133U shifted by an appropriate angle of more than 0 degrees and less than 90 degrees in the clockwise direction when viewed from the user. The support unit 500 or the hand unit 200 is supported at a position rotated by the angle. Note that the angle can be determined as appropriate, but preferably 15 to 75 degrees, more preferably 30 degrees, considering that a human performs an operation of grasping or releasing an object on a desk in normal life. -60 degrees, more preferably 40 degrees to 60 degrees, and most preferably about 45 degrees.

  The support unit 500 or the hand unit 200 is further rotatably supported around a rotation shaft 541 that is inserted into the shaft hole 141 in the end portion of the end portions 133R and 133U. Here, if a free-stop hinge mechanism is employed for the supported portion 511 including the rotation shaft 541, the hand unit 200 can be set to a desired palmar bending position according to the work content. This setting can be made by using, for example, fingers of an arm that is not cut or by abutting the finger member of the hand unit 200 against some stationary object. Thus, the user can work in a comfortable posture by changing the palm bending angle of the hand unit 200 to a desired angle according to the work content. Note that the position of the rotation axis 541, that is, the rotation center of palmar dorsiflexion, is not a radiused wrist joint that is a wrist joint, but a position corresponding to a joint of a healthy person's finger (metacarpal joint). It is preferable to do.

(1-4) Gripping Function Unit of Hand Unit FIG. 4 is a front view of the gripping function unit of the hand unit, and the arrangement of the finger members according to the present embodiment will be described with reference to FIG. The gripping function unit 300 of this example has three finger members 311, 312, and 313, which are the first finger (big finger), the second finger (indicator finger), and the third finger (middle finger) of a healthy person's hand, respectively. ) At the end of the drive unit 400 with a positional relationship corresponding to That is, when viewed from the front with these finger members open as shown, the finger member 311 corresponds to the Y-shaped trunk portion, and the finger members 312 and 313 correspond to the left and right branch portions of the Y-shape, and accordingly The interval between the finger members 311 and 312 and the interval between the finger members 311 and 313 are larger than the interval between the finger members 312 and 313, and the healthy person uses the first to third fingers. Thus, a state close to trying to grip an object is realized. Further, by adopting the arrangement of the finger members as in this example, three entry directions of the object are secured when gripping the object, so that it is difficult to turn the arm in and out, or only the grip function unit 300 Even if an operation that cannot be performed is required, it is possible to supplement with a minimum compensation operation using movements of the shoulders and the waist. Furthermore, the fact that having three finger members enables a gripping operation by a gripping force in addition to the conventional pinching operation of the active hook is also a great feature. In addition, when it is not necessary to distinguish these finger members from each other, they are comprehensively referred to by reference numeral 310.

  FIG. 5 is a view showing the hand unit 200 from below with the cap removed from some of the finger members (finger members 311). As shown in this figure, for example, a silicone rubber cap 350 can be detachably attached to the distal end side extending portion of each finger member 310, thereby enabling replacement of the cap at the time of fouling, It is possible to realize a non-slip function when gripping an object and a function of protecting the tip of a finger member or a gripping object.

  FIG. 6 is a view showing the hand unit from below with the tip portion removed from some finger members. The finger member 310 includes a distal end side extending portion 321 serving as a part where the cap 350 is attached and gripping an object, and a proximal end side extending portion 323 whose proximal end is linked to the driving unit 400. The distal end side extending portion 321 is attached so as to be rotatable with respect to the rotation shaft 327 of the proximal end side extending portion 323 forming the joint portion, and the distal end side extending portion 321 is extended to the proximal end side on the rotation shaft 325. A torsion spring 327 is provided that imparts a turning behavior in a direction to bend the portion 323 at a predetermined angle (for example, 135 degrees). As a result, when the gripping function unit 300 is closed, the tips of the three finger members 310 can be brought into close contact with each other without gaps, and the gripping property of the small article is improved and an excessive force is applied to the gripping object. Can be prevented from acting.

(1-5) Opening / Closing Mechanism of Gripping Function Unit FIGS. 7 to 9 are shown from below in a state where a part of the hand unit is seen through in order to explain the opening / closing mechanism and opening / closing operation of the finger member or the holding function unit. FIG. 7 shows a state in which the finger member or the gripping function unit is closed, FIG. 9 shows an open state, and FIG. 8 shows an intermediate state therebetween.

  In these drawings, what is indicated by reference numeral 401 is a linear motor that forms the main part of the drive unit 400, and the protruding position of the mover or the rod 403 can be positioned. The base end portion of the base end side extending portion 323 of the finger member 310 is connected to a connecting portion 405 provided at the tip end of the rod 403, while the side portion of the base end side extending portion 323 is the front end side of the drive unit 400. Is restricted by a restriction groove 413 of a disk-shaped opening / closing drive member 411 disposed in In addition, a torsion spring (not shown) or the like gives the proximal end side extending portion 323 a turning habit in a direction in which the side portion is positioned in the restriction groove 323.

  Accordingly, in the position shown in FIG. 7 in which the rod 403 is completely retracted, the base end portion of the base end side extending portion 323 is drawn inward of the housing 421 of the drive unit 400, and the base end side extending portion 323 is In order to be regulated by the regulating groove 413 at the side position separated from the end of 403, it is displaced in a direction that forms a small angle with respect to the axis of the rod 403. At this time, since the distal end side extending portions 321 are close to each other by the action of the torsion spring 327, the distal ends come into contact with each other. Hereinafter, the state illustrated in FIG. 7 is also referred to as a closed state of the gripping function unit 300.

  When the rod 403 is advanced, that is, protruded from the state of FIG. 7, as shown in FIG. 8, the base end side extending portion 323 is pushed out toward the outside of the housing 421, and the base end side extending portion is The angle of the H.323 increases with respect to the axis of the drive unit 400 while its side is regulated and guided by the regulation groove 413 of the opening / closing drive member 411. In the position shown in FIG. 9 in which the rod 403 completely protrudes, the proximal-side extending portion 323 is regulated by the regulating groove 413 at the side portion close to the end portion of the rod 403, and the axial line of the rod 403 In order to displace in a direction that forms a large angle with respect to the base end extension portion 323, and thus the tip end extension portion 321, are separated from each other radially (Y-shape as described above). Hereinafter, the state illustrated in FIG. 9 is also referred to as an open state of the gripping function unit 300.

  As will be described later, in the present embodiment, the position or protrusion amount of the mover of the linear motor 401, that is, the rod 403 is controlled by detecting a change in the shape of the skin surface as the user contracts / relaxes muscles. Is. As the linear motor, for example, an L12 Mini Linear Actuator manufactured by Fergelli can be used, and the protruding amount of the rod of the linear motor can be controlled in the range of 0 to 20 mm. Whether the user makes the rod 403 fully projecting or not projecting when the user exerts muscular contraction or when the muscle relaxes in a natural state, that is, the gripping function unit 300 is opened or closed. However, in order to reduce the load on the user who works while holding an object, the hand unit 200 may be configured so that the grip function unit 300 is closed when the muscle is relaxed. preferable.

  Patent Document 1 proposes a configuration in which a linear actuator is provided as a drive source for opening and closing three finger members. However, in this document, the arrangement of the three finger members, the mechanism for separating the finger members radially (Y-shaped), and the finger members are basically two-body structures and the torsion springs 327 are provided at their joints. There is no disclosure or suggestion about the arrangement to be arranged, and therefore the operational effects of the present embodiment as described above cannot be achieved.

(6) Sensor Unit FIGS. 10A and 10B are a bottom view showing an external configuration of a sensor unit that detects a change in skin surface shape and a schematic side view for explaining the detection principle. In the present embodiment, the reflection type optical distance sensor 470 is used for non-contact detection of changes in the shape of the skin surface accompanying changes in muscle contraction (changes in the height of the skin surface since muscle relaxation). In other words, a change in the skin surface shape is detected as a change in the distance between the optical distance sensor 470 and the skin surface 11 (hereinafter referred to as a sensor-skin distance). A member 474 that supports the optical distance sensor 470 is carried by a spacer 472 made of a soft material such as sponge, and the optical distance sensor 470 is positioned at a distance from the skin surface 11 by disposing the spacer 472 on the skin surface 11. Retained.

  As the optical distance sensor 470, for example, SG-105 manufactured by KODENSHI INC. Having an LED 470E that emits infrared light toward the skin surface 11 and a phototransistor 470P that receives reflected light from the skin surface 11 is used. The sensor-skin distance can be detected based on the voltage resistance value that changes according to the amount. The spacer 472 can hold the optical distance sensor 470 at a position where the distance between the sensor and the skin is about 3 mm when the muscle is relaxed. Further, the optical distance sensor 470 may be disposed near the skin immediately above the forearm ulnar carpal flexor muscle, which is a part where the change in the height of the skin surface according to muscle contraction for palmar flexion of the wrist joint, for example. it can.

  As described above, in this embodiment, the optical distance sensor 470 detects a skin shape change at the cut end, and opens and closes the gripping function unit 300. The optical distance sensor 470 is simpler and less expensive than the myoelectric sensor used in the myoelectric prosthesis, is easily insulated, and is less prone to malfunction due to sweating. Further, since only the soft spacer 472 contacts the skin and the hard sensor can be structured not to contact the skin directly, the skin is not damaged.

  In addition, an electric prosthetic hand using a pressure-sensitive sensor in which an output signal changes linearly by a displacement generated according to the magnitude of a force applied from the skin is proposed instead of a myoelectric sensor (Patent Document 2). However, since the pressure-sensitive sensor is disposed in close contact with the skin in structure, it can be influenced by the skin state at the position of placement as in the case of the myoelectric sensor. Using a non-contact sensor is effective for stable detection.

2. Control System (2-1) Configuration of Control System FIG. 11 shows a configuration example of a control system of the hand unit 200 according to the present embodiment. In the figure, what is indicated by reference numeral 450 is a control unit, on which a CPU 451, ROM 453, RAM 455, EEPROM 457, and I / O 459 are mounted. The CPU 451 controls each unit according to a program corresponding to the control procedure stored in the ROM 453. The ROM 453 stores necessary fixed data in addition to a program corresponding to a control procedure described later with reference to FIG. The RAM 455 has a data storage area and a storage area used as a work area. The EEPROM 457 can store parameters used in the control process, for example, parameters for driving the linear motor 401. The detection value (analog quantity) of the optical distance sensor 470 is converted into a digital quantity by the A / D converter 461 and provided to the CPU 451 via the I / O 459 which is an input / output unit. Further, a drive signal for the linear motor 401 generated by the CPU 451 and output from the I / O 459 is supplied to the linear motor 401 via the motor driver 463.

  An operation / display unit 480 is further connected to the I / O 459 to receive a user's operation input and perform necessary notification to the user. For example, the operation / display unit 480 includes an on / off switch of a power source (not shown), a switch (calibration switch) for starting calibration described later, and a lamp (notifying that the power is on) A power-on lamp) and a lamp (calibration lamp) for notifying the execution of calibration can be provided. Instead of the notification by display or together with it, it can be configured to perform notification by voice.

  For example, the A / D converter 461 and the motor driver 463 can be housed in the drive unit 400 together with the control unit 450. Further, the operation / display unit 480 can be arranged on the exterior of the drive unit 400.

(2-2) Control Procedure FIG. 12 shows an example of the control procedure of the hand unit 200 using the above configuration. This procedure may be started when the user wears the electric prosthesis according to this embodiment and performs a power-on operation using, for example, an on / off switch provided in the operation / display unit 480. it can. As the power source, for example, a lithium ion battery can be used, and power is supplied to each required unit in accordance with a power-on operation.

  When the procedure of FIG. 12 is started, first, in step S1, after performing necessary initial processing including the start of sampling of the detection value of the optical distance sensor 470, it is determined whether or not calibration execution is instructed in step S3. judge. If an affirmative determination is made here, calibration shown in steps S5 to S9 is performed. The calibration is performed to optimize the driving of the linear motor 401 or the opening / closing operation of the gripping function unit 300 according to the individual difference or physical condition of the user, and is versatile and not specialized for a specific individual. This is a feature of the electric prosthesis of this embodiment. In steps S5 and S7, the sensor-skin distance is detected during muscle relaxation (natural state) and muscle contraction (muscle strength exertion state) in accordance with the operation of the calibration switch, respectively. A parameter (Xstate) and a muscle strength exertion state parameter (Xmax) are acquired. In step S9, the drive parameters of the linear motor 401 are further calculated based on these parameters and set in the EEPROM 457.

  FIG. 13 is an explanatory diagram for explaining a mode of calibration. In this example, in consideration of the variation in detection, in both steps S5 and S7, for example, a simple moving average of 10 detection values (Xi; i = 0 to 9) is calculated at a sampling frequency of 100 Hz, An average value of 100 moving average values (Xmi; i = 0 to 99) is further calculated to be a natural state parameter (Xstate) and a muscle strength exertion state parameter (Xmax), respectively. Further, a value (a) obtained by dividing the maximum protrusion amount Lmax of the mover or rod of the linear motor 401 by the absolute value (Xdifference) of the difference between these parameters is set in the EEPROM 457 as a drive parameter of the linear motor 401. In use, the moving average value (Xmi) of 10 detected values is calculated in the same sampling cycle, and this is multiplied by the drive parameter (a), so that the rod protrusion amount according to the muscle contraction state of the user. And the linear motor 401 can be driven.

  Note that when the user performs calibration, the calibration lamp can be appropriately turned on, blinked, and turned off. For example, when the calibration switch is operated immediately after startup and during acquisition of the natural state parameter, it is lit, and after the acquisition is completed, the blinking state is used to prompt the calibration switch to be operated again in order to acquire the muscle strength state parameter. In addition, the lighting state can be turned on during acquisition of the muscular strength exertion state parameter, and the lighting state can be turned off when a series of calibrations are completed. Since the calibration is completed only by operating the calibration switch twice, it is possible for the user alone to perform the calibration with a simple operation.

  Referring to FIG. 12 again, after the above calibration process is completed or when the user does not want to execute the calibration, the process proceeds to step S11, and the drive parameter (a) set in the EEPROM 457 is changed. Then, the rod projection amount is determined by multiplying the moving average value (Xmi) of the detection values acquired at the time of use, and the linear motor 401 is driven so as to obtain the projection amount in step S13. Thereby, the user can adjust the opening of the gripping function unit 300 according to the intention. In addition, if the rod protrusion amount determined in step S11 has not changed so far, the process in step S13 can be skipped.

  Next, in step S15, it is determined whether or not a power-off operation has been performed. If a negative determination is made, the process returns to step S3, and the subsequent processing is repeated. On the other hand, if an affirmative determination is made, the process proceeds to step S17, where a required end process (for example, a process in which the rod is completely retracted and the gripping function unit 300 is closed) is performed, and then the power is turned off and Exit.

(3) Effects of the embodiment According to the present embodiment, in this research, both high workability such as an active prosthesis and high operability such as a myoelectric prosthesis can be achieved. In addition, because it is versatile, it can be easily attached in a flexible manner to cut ends that can have various dimensions, and it has an interface that can suppress the occurrence of scratches and inflammation, Compared to sockets used in active prosthetic hands and myoelectric prosthetic hands, there is no sense of restraint and it is lightweight, and in addition, relatively inexpensive components can be used as motors and sensors. Can be realized. Furthermore, compared to myoelectric prosthetic hands, which are based on the assumption that surface myoelectric potential is sensed by an electromyographic sensor, by detecting a change in the shape of the skin surface using a non-contact sensor, the effect of the skin condition of the forearm amputee can be reduced. It is difficult to receive and stable detection or operation becomes possible.

  When the electric prosthetic hand according to the above-described embodiment is actually manufactured and attached to the forearm amputee, it is confirmed that the operation can be performed in a short time training, and the grasping function unit against the change in the shape change of the skin surface It was confirmed that the opening and closing of the door responded with high accuracy and reproducibility. Furthermore, when we conducted an upper limb function evaluation using SHAP (Southampton Hand Assessment Procedure), an evaluation test of upper limb function developed in the UK, it is lightweight and can handle even small objects sufficiently. The possibility of having utility became clear.

(4) Other Embodiments In the above-described embodiments, the case where the present invention is applied to an electric prosthesis has been described. However, the present invention can be applied not only to a user who has lost a forearm, but also to a self-help device for a healthy person. A healthy person as used herein refers to a person whose forearm is present but whose forearm or finger function is incomplete due to cerebral infarction or nerve damage.

  FIG. 14 is a perspective view showing an external configuration example of a self-helper as an embodiment of the electric gripping device of the present invention, and parts that can be configured similarly to the electric prosthetic hand shown in FIG. It is. The self-help tool according to this embodiment is different from the above-described electric prosthesis in the structure of the interface unit.

  That is, the interface unit 100 ′ according to the present embodiment is similar to the interface unit 100 in the structure on the proximal end side close to the shoulder, but the structure on the distal end side is bent to avoid the forearm or finger of a healthy person. It is the point which has the terminal part 133R 'and 133U' which extend. In FIG. 14, a separate end portion is connected to and integrated with the main body of the interface unit 100 ′, but may be integrally formed in advance. Further, similarly to the above, the end portions 133R and 133U are shifted in the circumferential direction with respect to the main body of the interface unit 100 ′ so that the support unit 500 or the hand unit 200 is supported at a position rotated by an appropriate angle. However, such a shift is not always necessary if the healthy person can perform the pronation.

  According to this embodiment, the self-help tool which can achieve the effect similar to the electric prosthesis mentioned above can be provided to a healthy person. Further, as is apparent from the figure, the hand unit 200 can adopt the same configuration as that used for the electric prosthetic hand, and is highly versatile in that sense.

(5) Others The present invention is not limited to the above-described embodiments, and appropriate modifications and changes can be made without departing from the scope of the present invention.

  For example, in the above example, the interface unit has been described as a 3D printer made of ABS resin, but it is also possible to use a material with higher rigidity in consideration of lifting a relatively heavy object. Appropriate ones can be adopted for. Moreover, about the spring employ | adopted as a finger member, an appropriate member is employable, without being restricted to a torsion spring, The spring constant can also be selected appropriately. Furthermore, in order to detect a change in skin shape, the optical distance sensor is used in the above-described embodiment. However, the distance between the sensor and the skin can be detected using an ultrasonic sensor, and the distance is measured. Not only a thing but the structure which detects the change of surface shape itself by scanning slit light may be employ | adopted. In addition, in the above-described embodiment, the configuration using a linear motor as a drive source for opening and closing the gripping function unit has been described. However, a linear motion mechanism such as a solenoid, or a mechanism in which a rotary motor and a cam are combined. Etc. can also be used. However, in order to provide an electric gripping apparatus and a hand unit for the apparatus that are lightweight, inexpensive and excellent in stability while achieving both workability and operability, the components employed in the above-described embodiments are used. May be preferred.

100, 100 'interface unit 121I, 121O, 131I, 131O Notch portion of interface unit 123R, 123U Base end side portion of interface unit 133R, 133U, 133R', 133U 'End side portion of interface unit 200 Hand unit 300 Gripping function Portions 310, 311, 312, 313 Finger member 321 Finger member distal end side extending portion 323 Finger member proximal end side extending portion 327 Torsion spring 400 Drive portion 401 Linear motor 403 Movable element (rod)
411 Opening / closing drive member 413 Restriction groove 450 Control unit 470 Optical distance sensor 472 Spacer 480 Operation / display unit 500 Support unit 541 Rotating shaft

Claims (5)

An electric gripping device that can be mounted on the upper forearm,
A non-contact sensor that detects changes in the skin surface that appear as the upper forearm muscle contracts and relaxes;
According to the detected skin surface change, a plurality of finger members capable of taking a closed state in which the tips contact each other and an open state in which the tips are radially open, and a drive source driven by energization are driven. In response, a hand unit having an opening and closing mechanism for displacing the plurality of finger members so as to be in the open state and the closed state;
A pair of proximal end portions for receiving the upper portion of the forearm, facing each other through the opening portion, a pair of distal end portions for supporting the hand unit, facing each other through the opening portion, and the proximal end side An interface unit having an open part continuous from the position to the distal side,
The ingredients example,
The pair of distal side portions is formed with a positional relationship shifted with respect to the pair of proximal side portions by a predetermined angle in the pronation direction of the forearm to be attached . The interface unit is a member having a hollow, substantially cylindrical shape with both ends open as a basic shape, and has a pair of substantially U-shaped notches facing the open end on the base end side. And a pair of substantially U-shaped notches facing the distal open end, thereby forming the pair of proximal end portions and the pair of proximal ends. of that one of the one and the pair of cut of the distal notch section of the cutout portion is connected, the electric gripping device according to claim 1, characterized in that the continuous opening is formed. The electric gripping device according to claim 1 or 2 , which functions as a prosthetic hand for a forearm defect person. The electric gripping device according to claim 1 or 2 , wherein the electric gripping device functions as a self-help device for a person with a malfunctioning finger, and the end portion is bent to avoid the finger. A support having a support portion for supporting the hand unit, and a supported portion that is supported so as to be rotatable about a rotation shaft inserted between the pair of end portions and to be locked at the rotation position. The electric gripping device according to any one of claims 1 to 4 , further comprising a unit.

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