JP2018034218A - Finger mechanism and robot hand comprising finger mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily perform an operation return.SOLUTION: A finger mechanism comprising: a motor 31 as a driving source; a one-way power transmission mechanism 34 which can transmit a torque added to an input rotary body from the motor side to an output rotary body, and locks the output rotary body when a torque is added to the output rotary body from an output side; and an action part 35 which acts by the torque of the output rotary body. A rotary shaft 31a on the driving source side of the one-way power transmission mechanism 34 is provided with a torque input part 31b1 which connects an auxiliary driving source 40 and inputs a torque from the auxiliary driving source 40.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a finger mechanism that is provided at the end of a hand robot or the like and performs an operation on an object, and a robot hand equipped with the finger mechanism.

Conventionally, in this type of invention, for example, as described in Patent Document 1, the first actuator (8) as a drive source and the rotational motion of the first actuator (8) are linearly moved in the horizontal direction. A ball screw (8a) to be converted into a slide screw, a slide member (8b) screwed into the ball screw and moving in the horizontal direction, a second actuator (9) as a drive source supported by the slide member, and a second There is a gripping robot device provided with three sets of finger mechanisms each having a worm gear (9a) that transmits the rotational force of the actuator (9) and a gripping lever (10) that meshes with the worm gear (9a) and rotates.
This gripping robot apparatus grips a gripping object by using the first actuator (8) and the second actuator (9) as driving sources and changing the intervals and angles of the plurality of gripping levers (10).

JP 2009-50968 A

  By the way, in the conventional gripping robot apparatus as described above, for example, when an abnormality occurs on the drive source side such as a power failure, disconnection, emergency stop, or drive source failure in the state of gripping the object to be gripped, Unless the interval and angle of the grip lever (10) are maintained and the power supply is not restored, it is difficult to open and close the grip lever (10). In addition, the numerical value in the said parenthesis is the code | symbol described in patent document 1. FIG.

In view of such problems, the present invention has the following configuration.
The motor that is the drive source and the rotational force applied to the input rotator from the motor side can be transmitted to the output rotator, and when the rotational force is applied to the output rotator from the output side, the output rotator is locked. A directional power transmission mechanism and an operation unit that operates by the rotational force of the output rotator, and an auxiliary drive source is detachably connected to the rotation shaft on the drive source side of the unidirectional power transmission mechanism. A finger mechanism comprising a rotational force input unit for inputting rotational force from a drive source.

  Since the present invention is configured as described above, even when the operation is stopped due to an abnormality on the drive source side, the operation can be easily restored.

It is the schematic which shows an example of the robot hand provided with the finger mechanism which concerns on this invention. It is a schematic structure figure showing an example of a finger mechanism concerning the present invention. It is a principal part enlarged view of the same finger mechanism. FIG. 4 is an essential part enlarged view showing a state where an auxiliary drive source is connected to the finger mechanism of FIG. 3. It is a schematic structure figure showing other examples of the finger mechanism concerning the present invention. It is a principal part enlarged view which shows the state which connected the auxiliary drive source to the finger mechanism of FIG.

The first feature of the finger mechanism in the present embodiment is that a motor that is a driving source and a rotational force applied to the input rotator from the motor side can be transmitted to the output rotator, and a rotational force from the output side to the output rotator. Is added to the rotary shaft on the drive source side of the one-way power transmission mechanism, and includes a one-way power transmission mechanism that locks the output rotator and an operation unit that operates by the rotational force of the output rotator. Is provided with a rotational force input section for detachably connecting an auxiliary drive source and inputting rotational force from the auxiliary drive source (see FIGS. 2 to 6).
Here, the “auxiliary drive source” includes a mode in which the rotation input unit is rotated by an electric motor, a mode in which the rotation input unit is manually rotated, and the like.
The “rotary shaft on the drive source side of the one-way power transmission mechanism” includes the rotation shaft of the motor, the rotation shaft on the drive source side in the one-way power transmission mechanism itself, and the like.
Further, the rotation input unit may be singular or plural.
The finger mechanism includes a mode in which the auxiliary drive source is not mounted and a mode in which the auxiliary drive source is mounted in advance.

  A second feature is a gear in which the rotational force input portion is fixed to the rotational shaft as an aspect for facilitating the input of rotational force (see FIGS. 2 to 6).

  A third feature is that, as a preferred specific embodiment, the rotating shaft is a rotating shaft of the motor (see FIGS. 2 to 6).

  As a fourth feature, the motor and the one-way power transmission mechanism are arranged in parallel, and configured to transmit rotational force by a plurality of gears, as an aspect that enables shortening of the entire mechanism. At least one of the plurality of gears is provided with the rotational force input unit (see FIGS. 2 to 4).

  A fifth feature is that the motor and the one-way power transmission mechanism are connected in series so that the whole mechanism can be slimmed down, and the rotary shaft closer to the drive source than the one-way power transmission mechanism is connected. A gear is fixed, and a part of the gear is exposed to serve as the rotational force input unit (see FIGS. 5 to 6).

  According to a sixth feature, as a specific aspect having good convenience, the auxiliary drive source is mounted in advance so as to input a rotational force to the rotational force input unit (see FIGS. 4 and 6).

  The seventh feature is that, as a specific aspect excellent in operability, the operating portion is rotatable to a proximal end side link supporting the motor and the one-way power transmission mechanism, and to a distal end side of the proximal end side link. A distal end side link connected to the proximal end side link, a feed screw mechanism that is supported by the proximal end side link and receives rotational force from the output rotating body to the feed screw, and one end side is pivotally supported by a nut portion of the feed screw mechanism And an operation link pivotally supported at the other end around the rotation axis of the distal link, and the distal link is rotated with respect to the proximal link by the advancement and retraction of the nut portion as the feed screw rotates. (See FIGS. 2 to 6).

  The eighth feature is that, as a preferred mode of use of the finger mechanism, a robot hand is configured with at least one finger mechanism (see FIGS. 1 and 2).

<First Embodiment>
Next, specific embodiments having the above characteristics will be described in detail with reference to the drawings.

FIG. 1 shows a robot hand 1 having a plurality of finger mechanisms according to the present invention.
The robot hand 1 includes a plurality of fingers 10 that protrude in substantially the same direction and are spaced apart from each other by a palm body 20.

  Each finger 10 has a finger shaft hollow joint 10a, 10b connected to the front and back, a rotation axis a that inverts and spins between the palm 20 and the joint 10a, and a palm. 20 and a rotating shaft b that bends and extends between the node portion 10a and a rotating shaft c that bends and extends between the node portion 10a and the node portion 10b. The finger mechanism 30 provided for each of b and c makes a movement such as bending, progressing, adduction and abduction like a human hand.

  The node portions 10a and 10b may be formed of an elastic material such as elastic synthetic resin or rubber, for example. In addition, as another example of the node portions 10a and 10b, it is possible to adopt a mode in which cylindrical bodies made of a hard material such as metal are connected back and forth via a rotating shaft.

Next, the finger mechanism 30 corresponding to the rotation axis c will be described in detail as a particularly preferable aspect among the plurality of finger mechanisms corresponding to the rotation axes a, b, and c.
The finger mechanism corresponding to each of the other rotation axes a (or b) may have the same configuration as the finger mechanism 30, but may be configured other than the finger mechanism 30.

  2 to 4, the finger mechanism 30 adjusts the speed of a motor 31 that is a drive source, a rotation detection unit 32 that detects a rotation angle of the motor 31, and a rotational force transmitted from the motor 31. The speed control unit 33, the one-way power transmission mechanism 34 that transmits the rotational force transmitted from the speed control unit 33 only in one direction, and the operation unit 35 that is operated by the torque on the output side of the one-way power transmission mechanism 34. The auxiliary drive source 40 is connected to a rotary shaft 31a that transmits a rotational force on the drive source side of the one-way power transmission mechanism 34 (between the speed adjusting unit 33 and the motor 31 according to the illustrated example). A rotational force input unit 31b1 for inputting rotational force from the auxiliary drive source 40 is provided.

The motor 31 may be an electric motor that can control the bidirectional rotation angle. For example, a brushless motor is used, and the rotation angle (or rotation amount) is controlled by a control unit (not shown).
An output gear 31 b is provided on one end side (output side) of the rotation shaft 31 a of the motor 31, and the other end side is connected to the rotation detection unit 32.

According to the illustrated example, the output gear 31b is a spur gear, and a part of the outer peripheral portion thereof is exposed as a rotational force input portion 31b1 to which the auxiliary drive source 40 is connected.
The skin portion 11 of the node portion 10a is provided with an opening (not shown) through which the auxiliary drive source 40 is inserted.

  The rotation detection unit 32 is a rotary encoder. As another example of the rotation detection unit 32, a rotation angle sensor using a Hall element, a rotation angle sensor using a variable resistor, or the like can be used. The output of the rotation detection unit 32 is transmitted to a control unit (not shown).

According to a preferred example of the present embodiment, the speed control unit 33 uses a planetary gear mechanism (not shown) that transmits a rotational force coaxially.
The speed control unit 33 appropriately reduces the rotational force input by the input gear 33a by the planetary gear mechanism and transmits the rotational force to a one-way power transmission mechanism 34 described later.
The input gear 33 a is a spur gear that meshes with the output gear 31 b of the motor 31.
In addition, as another example of the speed control part 33, it is also possible to use gear mechanisms other than a planetary gear mechanism, and another reduction mechanism.

The one-way power transmission mechanism 34 can transmit the rotational force applied to the input rotator (not shown) from the speed control unit 33 to the output rotator 34a, and when the rotational force is applied to the output rotator 34a from the output side. Is a mechanism for locking the output rotator 34 a, which is connected in series to the speed control unit 33 and arranged in parallel to the motor 31.
An output gear 34b is fixed coaxially to the output rotating body 34a.
For the one-way power transmission mechanism 34, for example, the invention disclosed in the republished patent WO2013 / 133162 can be used.
Alternatively, the invention disclosed in the republished patent WO2013 / 164969 can be used as a mechanism in which the speed control unit 33 and the one-way power transmission mechanism 34 are integrated.

  As another example of the one-way power transmission mechanism 34, a worm gear mechanism, a sliding screw mechanism, a mechanism in which these mechanisms are appropriately combined, or the like can be used.

  The operating unit 35 includes a proximal end side link 35a, a distal end side link 35b rotatably connected to the distal end side of the proximal end side link 35a, a feed screw mechanism 35c supported by the proximal end side link 35a, An operation link 35d pivotally supported between the feed screw mechanism 35c and the distal end side link 35b is provided, and the distal end side link 35b is rotated with respect to the proximal end side link 35a to bend and extend between the node portions 10a and 10b. Let

The proximal end side link 35a is a member extending in the longitudinal direction in the node portion 10a, and supports the motor 31, the rotation detecting unit 32, the speed adjusting unit 33, the one-way power transmission mechanism 34, and the like.
The base end side link 35a is formed of, for example, a hard material such as metal in a cylindrical shape or a frame shape, and exposes the rotational force input portion 31b1 to the outside.

The distal end side link 35b is a member extending in the longitudinal direction in the node portion 10b, and the proximal end side thereof is rotatably supported on the distal end side of the proximal end side link 35a via the rotation shaft 35b1. .
The distal end side of the distal end side link 35b is joined to the inner surface of the skin portion 11 on the distal end side of the node portion 10b via an extending member 36 and an elastic member 37.
As another example, the extending member 36 and the elastic member 37 may be omitted, the distal end side of the distal end side link 35 b may be extended, and directly joined to the inner surface of the skin portion 11.

The feed screw mechanism 35c includes a feed screw 35c1 rotatably supported by the base end side link 35a, a spur gear-like input gear 35c2 fixed to the input side end of the feed screw 35c1 and meshed with the output gear 34b, A nut portion 35c3 screwed to the output side of the feed screw 35c1 is provided, and the feed screw 35c1 is rotated by the rotational force transmitted from the one-way power transmission mechanism 34.
The feed screw mechanism 35c includes a ball screw mechanism, a sliding screw mechanism, and the like.

  The actuating link 35d is pivotally supported at one end side by the nut portion 35c3 and pivotally supported at the other end side by the distal end side link 35b.

The auxiliary drive source 40 is provided independently of the robot hand 1, and includes a motor 41, a battery 42 serving as a power source for the motor 41, a control circuit (not shown) for controlling the motor 41, and an operation. A switch (not shown) and the like are integrally provided.
The motor 41 can be a brushless motor or other electric motor, similar to the motor 31.
The rotation shaft 41a of the motor 41 is provided with a spur gear-like output gear 41b.

  The auxiliary drive source 40 having the above configuration can be attached to the base end side link 35a and can be detached from the base end side link 35a so that the output gear 41b meshes with the rotational force input portion 31b1. The means for enabling the auxiliary drive source 40 to be attached to and detached from the proximal end side link 35a may be, for example, screwing or fitting.

Next, the characteristic effect of the finger mechanism 30 having the above-described configuration will be described in detail.
When the rotating shaft 31a of the motor 31 is rotated in one direction under the control of a control unit (not shown), the rotational force is transmitted through the output gear 31b, the input gear 33a, the speed control unit 33, and the one-way power transmission mechanism 34. It is transmitted to 35 feed screw mechanisms 35c.
Then, when the nut portion 35c3 moves to, for example, the input side (downward according to FIG. 2) due to the rotation of the feed screw 35c1 in one direction in the feed screw mechanism 35c, the tip is moved by the operation link 35d pivotally supported by the feed screw mechanism 35c. The side link 35b is pulled, the distal end side link 35b rotates about the rotation shaft 35b1, and the node portions 10a and 10b are bent.
Further, when the nut portion 35c3 moves to the output side (upward according to FIG. 2) due to the rotation of the motor 31 in the reverse direction, the extension between the node portions 10a and 10b is caused by the reverse action.

  Therefore, if a gripping object (not shown) is arranged between the plurality of fingers 10 in the robot hand 1 and at least one finger 10 is bent by the finger mechanism 30 or the like, the plurality of fingers 10 can grip the object to be gripped.

If the rotation of the rotary shaft 31a stops due to an abnormality on the drive source side, such as a power failure, disconnection, emergency stop, or failure of the motor 31, during the gripping operation by the bending motion of the finger body 10, one-way power transmission The bending state at that time is maintained by the function of the mechanism 34 and the like, and the finger body 10 cannot be extended even if an external force is applied to the node portion 10b.
In such a case, if the auxiliary drive source 40 is mounted on the finger 10 and an operation switch (not shown) of the auxiliary drive source 40 is operated to rotate the output gear 41b of the auxiliary drive source 40, this rotation The finger mechanism 30 is operated by force, and the finger body 10 can be bent or extended.

Therefore, according to the robot hand 1 having the above configuration, even when the operation is stopped due to an abnormality on the drive source side, the operation can be easily restored using the auxiliary drive source 40.
In addition, each joint can be flexed and extended individually, including adjustment of the force of gripping the object even during a power failure or failure.

<Second Embodiment>
Next, another embodiment will be described. In the embodiment described below, since the finger mechanism 30 of the robot hand 1 is changed to the finger mechanism 50, the changed part is mainly described in detail, and the same part as the robot hand 1 is duplicated. The detailed description to be omitted is omitted.

The finger mechanism 50 shown in FIGS. 5 to 6 is provided corresponding to the rotation axis c or the rotation axes a and b in the finger body 10 in the same manner as the finger mechanism 30 described above.
The finger mechanism 50 includes a motor 51 as a drive source, a rotation detection unit 52 that detects a rotation angle of the motor 51, a speed control unit 53 that adjusts the speed of the rotational force transmitted from the motor 51, and a speed control unit. A unidirectional power transmission mechanism 54 that transmits the rotational force transmitted from 53 in only one direction is connected in series, and the operation unit 35 that operates by the rotational force on the output side of the unidirectional power transmission mechanism 54 is connected thereto. Are connected in parallel, and a plurality of gears 51a, 54a are provided on a rotating shaft (not shown) that transmits a rotational force on the drive source side of the one-way power transmission mechanism 54, and the gears 51a, 54a are exposed. The part is a rotational force input part.

  The motor 51 is a brushless motor similar to the motor 31, and an output side portion of the casing is cut away to expose an outer peripheral portion of the gear 51 a fixed to a rotating shaft (not shown). The exposed portion of the gear 51a functions as a rotational force input unit.

  The rotation detection unit 52 is configured by an encoder or the like similarly to the rotation detection unit 32, detects the rotation angle of the motor 51, and transmits the detection signal to a control unit (not shown).

The speed control unit 53 is configured by a planetary gear mechanism in the same manner as the speed control unit 33. The speed control portion 53 has a notch on the input / output side portion of the casing covering the planetary gear mechanism. The cutout on the input side is continuous with the cutout in the casing of the motor 51.
The notch on the output side exposes the outer peripheral portion of the gear 54a fixed to the output-side rotation shaft (not shown) of the speed governor 53. The outer peripheral portion of the gear 54a functions as a rotational force input portion.

Similar to the one-way power transmission mechanism 34, the one-way power transmission mechanism 54 can transmit the rotational force transmitted from the speed control unit 53 to the output rotating body 54b, and the rotational force from the output side to the output rotating body 54b. This is a mechanism for locking the output rotator 54b when.
An output gear 54c is fixed coaxially to the output rotating body 54b.

  Since the operation unit 35 in the finger mechanism 50 is configured in substantially the same manner as the operation unit 35 of the finger mechanism 30, the same reference numerals as those of the finger mechanism 30 are used, and redundant detailed description is omitted.

  The auxiliary drive source 60 is detachably connected to the finger mechanism 50 having the above-described configuration as necessary.

The auxiliary drive source 60 is provided independently of the robot hand 1, and includes a plurality of (two in the illustrated example) motors 61 and 62, a battery 63 serving as a power source for the motors 61 and 62, and the motors 61, 62. A control circuit (not shown) for controlling 62, an operation switch (not shown) and the like are integrally provided.
Each of the motors 61 and 62 can be a brushless motor or other electric motor, similar to the motors 31 and 41.
The rotation shafts 61a and 62a of the motors 61 and 62 are provided with spur gear-like output gears 61b and 62b, respectively.

  The auxiliary drive source 60 configured as described above can be mounted on the proximal end side link 35a so that the output gears 61b and 62b are engaged with the exposed portions (rotational force input portions) of the gears 51a and 54a. It is also possible to leave from 35a. The means for making the auxiliary drive source 60 attachable to and detachable from the proximal end side link 35a may be, for example, screwing or fitting.

Therefore, according to the finger mechanism 50 shown in FIGS. 5 and 6, even when the operation is stopped due to an abnormality on the drive source side, the operation can be easily restored using the auxiliary drive source 60.
In addition, since the finger mechanism 50 is provided with a plurality of gears 51a and 54a having a rotational force input portion, a relatively large rotational force can be input from the outside.
Further, depending on the use situation or the like, only one of the gears 51a (or 54a) can be used as the rotational force input unit.

As a preferred embodiment, the finger mechanism 30 or the finger mechanism 50 is provided on each of the plurality of fingers 10 in the robot hand 1. As another example, only some of the fingers 10 among the plurality of fingers 10 are provided. Further, it is possible to adopt a mode in which the finger mechanism 30 or the finger mechanism 50 is provided.
That is, even if only one finger body 10 is bent and the other finger bodies 10 are not bent among the plurality of finger bodies 10, it is possible to grip the object to be grasped by these finger bodies 10. .

Moreover, although the auxiliary drive sources 40 and 60 of the above-described embodiment are configured to rotate the gears 41b and 61b electrically, as another example of the auxiliary drive source, a configuration in which the gears are manually rotated can be used. is there.
Furthermore, as another example, the rotational force input part 31b1 (or the outer peripheral part of the gears 51a and 54a) can be externally exposed so that it can be manually rotated.

  In addition, the operating unit 35 of the above embodiment is a mechanism that bends and extends between the proximal end side link 35a and the distal end side link 35b. However, the operating unit 35 is configured to operate by the rotational force of the output rotating bodies 34a and 54b. As other examples, a bending extension motion such as a mechanism for rotating the fingertip side of the finger body 10 by a rotational force of the output rotating bodies 34a and 54b, a mechanism for extending or contracting and sliding the fingertip side of the finger body 10, etc. It is possible to use a mechanism for performing operations other than the above.

  Moreover, according to the said embodiment, although the auxiliary drive sources 40 and 60 were separated from the rotational force input part 31b1 (or outer peripheral part of the gears 51a and 54a), it was set as the structure different from the finger body 10, Other examples As an example, the auxiliary drive sources 40 and 60 are connected in advance so as to input the rotational force to the rotational force input portion 31b1 (or the outer peripheral portion of the gears 51a and 54a) (see FIGS. 4 and 6). It is also possible. In this case, the motors 41, 61, 62 of the auxiliary drive sources 40, 60 are configured to freely rotate the output shaft in a non-energized state.

  Moreover, this invention is not limited to the embodiment mentioned above, In the range which does not change the summary of this invention, it can change suitably.

1: Robot hand 10: Finger body 10a, 10b: Node 20: Palm body 31, 41, 51, 61, 62: Motor 31a: Rotating shaft 31b1: Rotational force input unit 34, 54: One-way power transmission mechanism 35: Operating unit 40, 60: auxiliary drive source

Claims (8)

The motor that is the drive source and the rotational force applied to the input rotator from the motor side can be transmitted to the output rotator, and when the rotational force is applied to the output rotator from the output side, the output rotator is locked. A directional power transmission mechanism, and an operation unit that operates by the rotational force of the output rotator,
The rotational shaft on the drive source side of the one-way power transmission mechanism is provided with a rotational force input unit for detachably connecting the auxiliary drive source and inputting rotational force from the auxiliary drive source. And finger mechanism.   The finger mechanism according to claim 1, wherein the rotational force input unit is a gear fixed to the rotation shaft.   The finger mechanism according to claim 1, wherein the rotation shaft is a rotation shaft of the motor. The motor and the one-way power transmission mechanism are arranged in parallel and configured to transmit a rotational force by a plurality of gears,
The finger mechanism according to any one of claims 1 to 3, wherein the rotational force input portion is provided in at least one of the plurality of gears.   The motor and the one-way power transmission mechanism are connected in series, and a gear is fixed to a rotary shaft closer to the drive source than the one-way power transmission mechanism, and a part of the gear is exposed to input the rotational force. The finger mechanism according to any one of claims 1 to 3, wherein the finger mechanism is a part.   The finger mechanism according to claim 1, wherein the auxiliary drive source is mounted in advance so as to input a rotational force to the rotational force input unit.   The operation unit is supported by a proximal end link that supports the motor and the one-way power transmission mechanism, a distal end link that is rotatably connected to a distal end side of the proximal end link, and a proximal end link. A feed screw mechanism in which a rotational force is input from the output rotating body to the feed screw, and one end side is pivotally supported on the nut portion of the feed screw mechanism and the other end side is pivotally supported around the rotation axis of the tip side link. The said operation | movement link is provided, The said front end side link is rotated with respect to the said base end side link by advance and retreat of the said nut part accompanying rotation of the said feed screw, The any one of Claims 1-6 characterized by the above-mentioned. Finger mechanism.   A robot hand comprising at least one finger mechanism according to any one of claims 1 to 7.

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