JP7331466B2 - robot - Google Patents

Description

The present invention relates to a robot equipped with a rotary actuator having a motor and a rotation restricting mechanism for restricting rotation of the stopped motor, and having a plurality of joints and an arm connected to the joints.

As a conventional industrial robot, a base as a support member, a first arm connected to the base via a joint, a second arm connected to the tip side of the first arm via a joint, and a joint and a wrist connected to the distal end side of the second arm via a portion. Also, in this type of industrial robot, the joint portion includes a motor having a rotor and a stator, a speed reducer connected to the motor, and a safety brake for maintaining the rotor in a stopped state. is configured as a rotary actuator.

As a rotary actuator mounted on such an industrial robot, there is known one that includes a motor and a rotation restricting mechanism that restricts the rotation of the stopped motor (see, for example, Patent Document 1). .

In the rotary actuator mounted on the robot disclosed in Patent Document 1, the rotation restricting mechanism includes a disk-shaped rotation-side restricting member fixed to the rotor of the motor, and engages with the rotating-side restricting member to restrict its rotational movement. A pin-shaped regulating member and a driving mechanism for moving the regulating member in the axial direction of the rotor are provided. Further, a plurality of protrusions protruding radially outward of the rotor are provided on the peripheral edge of the rotation-side regulating member. At the tip of the restricting member, an annular restricting portion is provided that enters between the projections adjacent in the circumferential direction to restrict the rotational movement of the rotation-side restricting member.

JP 2017-189081 A

The rotary actuator mounted on the robot disclosed in Patent Document 1 has a structure in which the rotor is stopped and held by engagement (collision) between the protrusion and the restricting portion. Therefore, for example, when the restricting portion enters between the protrusions during rotation of the motor, the rotating force is transmitted to the restricting portion as it is until the rotor stops, and the impact force is imposed on the restricting portion. As a result, there is a possibility that an excessive force acts on one point where the protrusion and the restricting portion collide, and the protrusion and the restricting portion are damaged or deformed. Further, there are cases where it is desired to use the engagement between the protrusion and the restricting portion not only for holding the rotor but also for braking the rotor in an emergency. In this case, when the restricting portion enters between the protrusions during rotation of the motor, there is a possibility that the protrusion or the restricting portion may be dented, or the restricting portion may jump over the protrusion and the motor may not be stopped immediately. In such a case, a robot having a plurality of joints may move unexpectedly, leaving room for improvement in terms of durability and workability.

The present invention has been made in view of the circumstances described above, and by using both a compact and lightweight first rotation restricting mechanism and a second rotation restricting mechanism with large brake torque and high durability, the position of the joint can be adjusted. To provide a robot capable of introducing a rotation regulating mechanism suitable for each occasion and achieving both improved durability and improved workability of the robot.

(1)
A robot having a plurality of joints and an arm connected to the joints,
The plurality of joints includes at least one first joint including a motor and a first rotation restricting mechanism that restricts rotation of the motor, and at least one including a motor and a second rotation restricting mechanism that restricts rotation of the motor. a second articulation, and
The first rotation restricting mechanism is a mechanism for restricting rotation of the motor by inserting a first member between a plurality of projections formed on an outer peripheral portion of a first rotating body supported by a rotating shaft of the motor. and
The second rotation restricting mechanism restricts rotation of the motor by a frictional force generated by bringing a second member into contact with an end surface of a second rotating body supported by the rotating shaft of the motor in the direction of the rotating shaft. is a mechanism,
The second joint portion has a configuration in which a speed reducer, the motor, the second rotation restriction mechanism, and a detector that optically detects the rotational position of the motor are arranged in order from the torque output direction side,
A coil holder that houses a coil that generates a magnetic force for moving the second member in the rotation axis direction of the motor is provided between the second rotating body of the second rotation restricting mechanism and the detector. Robot .

In the robot of (1), a small and lightweight first rotation regulating mechanism and a large brake torque and high durability second rotation regulating mechanism are used together, and at least two types of stopping or braking mechanisms and characteristics are different from each other. A robot is configured including a rotation control mechanism. As a result, the type of rotation control mechanism can be appropriately selected according to the position of each joint based on the required torque of each joint of the robot, the characteristics of the robot as a whole, such as its overall size and weight, and its balance. The entire robot can be optimized in terms of stopping and braking parts. That is, it is possible to introduce a regulation mechanism suitable for each position of the joint portion, and to improve durability and workability of the robot at the same time.
In addition, since the coil holder is arranged between the second rotating body of the second rotation restricting mechanism and the detector, even if frictional powder from the second rotating body is generated due to the use of the second rotation restricting mechanism, However, the coil holder acts as a barrier to prevent the friction powder from entering the detector. This intrusion suppression can prevent it from affecting the operation of the detector.
(2)
A robot having a plurality of joints and an arm connected to the joints,
The plurality of joints includes at least one first joint including a motor and a first rotation restricting mechanism that restricts rotation of the motor, and at least one including a motor and a second rotation restricting mechanism that restricts rotation of the motor. a second articulation, and
The first rotation restricting mechanism is a mechanism for restricting rotation of the motor by inserting a first member between a plurality of projections formed on an outer peripheral portion of a first rotating body supported by a rotating shaft of the motor. and
The second rotation restricting mechanism restricts rotation of the motor by a frictional force generated by bringing a second member into contact with an end surface of a second rotating body supported by the rotating shaft of the motor in the direction of the rotating shaft. is a mechanism,
The second joint portion includes a magnet holder that is fixed to the rotating shaft of the motor and supports the magnet of the motor,
A polygonal hole is formed in the second rotating body of the second rotation restricting mechanism,
The robot, wherein the second rotating body is fixed to the magnet holder via an attachment that fits into the polygonal hole.
In the robot of (2), a small and lightweight first rotation regulating mechanism and a large brake torque and high durability second rotation regulating mechanism are used together, and at least two types of stopping or braking mechanisms and characteristics are different from each other. A robot is configured including a rotation control mechanism. As a result, the type of rotation control mechanism can be appropriately selected according to the position of each joint based on the required torque of each joint of the robot, the characteristics of the robot as a whole, such as its overall size and weight, and its balance. The entire robot can be optimized in terms of stopping and braking parts. In other words, it is possible to introduce a regulation mechanism suitable for each position of the joint, and to improve both durability and workability of the robot.
In addition, when assembling and producing the second rotation restricting mechanism, it is possible to facilitate the work process by providing a magnetization process after shrink-fitting and appropriately changing the process according to the arrangement order of the constituent members. can be done.

( 3 )
The robot according to (1) or (2) ,
Among the plurality of joints, the joint closest to the distal end is the first joint, and the joint closest to the proximal end is the second joint.

Here, in a robot having a plurality of joints and an arm connected to the joints, the front end side of the robot is generally required to be lightweight. For this reason, the first joint that is configured to include the compact and lightweight first rotation restricting mechanism is suitable for the joint that is arranged on the most distal end side. On the other hand, the base end side (base side) of the robot may be fixed to a fixed surface such as a ceiling surface or the ground, and in such a case, the required torque of the joint portion on the base end side becomes large. For this reason, the second joint portion that includes the second rotation restricting mechanism with large brake torque and high durability is suitable for the joint portion that is arranged on the most proximal side. That is, as in ( 3 ), by appropriately selecting and introducing a rotation control mechanism according to the position of the robot's distal end side and proximal end side, the robot as a whole is more appropriately optimized from the characteristics and balance of the robot as a whole. be able to.

( 4 )
The robot according to (1) or (2) ,
Among the plurality of joint portions, the joint portion for determining the three-dimensional position of the arm arranged on the most distal side is the second joint portion, and the joint portion connected to the distal side of the arm is the second joint portion. A robot with one joint.

Here, in a robot having a plurality of joints and an arm connected to the joints, the required torque for determining the three-dimensional position (mainly the position among the positions and orientations) of the arm on the tip side of the robot is generally growing. For this reason, the joint portion for that purpose is suitable for the second joint portion configured to include the second rotation restricting mechanism with large brake torque and high durability. On the other hand, since the joint connected to the distal end of the arm is mainly for determining the posture, the required torque for determining the position of the arm does not need to be so large. For this reason, the first joint that is configured to include the compact and lightweight first rotation restricting mechanism is suitable for the joint that is connected to the distal end side of the arm. That is, as in ( 4 ), by appropriately selecting and introducing the rotation control mechanism according to the degree of contribution to each arm's position determination or attitude determination, the entire robot can be more appropriately optimized from the characteristics and balance of the entire robot. can be

( 5 )
The robot according to (1) or (2) ,
Among the plurality of joints, the joint having an output torque equal to or less than a threshold is the first joint, and the joint having an output torque exceeding the threshold is the second joint.

When configured as in ( 5 ), in a robot having a plurality of joints and an arm connected to the joints, the rotation restricting mechanism is appropriately selected and introduced according to the magnitude of the output torque required for each joint. As a result, the entire robot can be optimized more appropriately based on the characteristics and balance of the robot as a whole.

( 6 )
The robot according to any one of ( 3 ) to (4),
comprising two said arms;
including six joints as the plurality of joints,
Of the six joints, the three joints arranged on the distal side are the first joints, and the three joints arranged on the proximal side are the second joints.

If the robot of ( 6 ) has six joints, it is not necessary for the required torque to be so large for the three joints located on the tip side. A configured first articulation is suitable. On the other hand, the three joints arranged at the proximal end require a larger torque than the three joints at the distal end. Therefore, the three joints arranged at the proximal end are suitable for the second joint that includes a second rotation restricting mechanism with large brake torque and high durability.

( 7 )
The robot according to any one of (1) to ( 6 ),
the second joint includes a housing that accommodates the motor and the second rotation restricting mechanism,
A hole through which an electric wire is passed is provided at an end of the housing in a direction orthogonal to the rotation axis direction of the motor,
The robot, wherein a reinforcing member is formed in the hole to reinforce the hole.

Here, when the second rotation restricting mechanism is mounted on a predetermined joint portion, the outer shape of the joint portion tends to increase in size, and accordingly the housing also increases in size. Therefore, with the configuration of ( 7 ), even if the second rotation restricting mechanism is mounted and the housing of the joint is enlarged, a reinforcing member is formed in the hole through which the electric wire is passed. can increase the strength of the housing. As a result, it is possible to suppress the vibration of the robot itself during operation of the robot.

(8)
( 1 ) The robot according to
In the robot, the gap between the coil holder and the rotor of the motor is a distance that suppresses the passage of abrasion powder generated by the contact between the second member and the second rotating body.

With the configuration of (8), the gap between the coil holder and the rotor of the motor is set to a distance that suppresses the passage of the frictional powder, thereby further suppressing the entry of the frictional powder into the detector. be able to.

(9)
(1 ) The robot according to
The second joint portion includes a magnet holder that is fixed to the rotating shaft of the motor and supports the magnet of the motor,
A polygonal hole is formed in the second rotating body of the second rotation restricting mechanism,
The robot, wherein the second rotating body is fixed to the magnet holder via an attachment that fits into the polygonal hole.

With the configuration as in (9), when assembling and producing the second rotation restricting mechanism, it is possible to provide a magnetization process after shrink-fitting and appropriately change the process according to the arrangement order of the constituent members. The process can be facilitated.

According to the present invention, a rotation restriction mechanism suitable for each joint position is introduced by using both a small and lightweight first rotation restriction mechanism and a large brake torque and high durability second rotation restriction mechanism. It is possible to improve the durability of the robot and improve the workability at the same time.

1 is a front view of an industrial robot according to an embodiment of the invention; FIG. (A) is a perspective view of the industrial robot shown in FIG. 1, and (B) is a perspective view showing how the industrial robot shown in (A) is operating. 1. It is a longitudinal cross-sectional view of the 4th joint part shown in FIG. 1, the 5th joint part, and the 6th joint part. FIG. 4 is an enlarged view for explaining the configuration of the G section shown in FIG. 3, where (A) is an enlarged view showing a state in which the regulation pin is in the regulation release position, and (B) is a state in which the regulation pin is in the regulation position; is an enlarged view showing the. 4 is a plan view of a rotation-side regulating member and a regulating pin shown in FIG. 3; FIG. It is a longitudinal cross-sectional view of the 1st joint part, the 2nd joint part, and the 3rd joint part which are shown in FIG. FIG. 7 is a cross-sectional view taken along line H of FIG. 6; FIG. 7 is a view in the direction of arrow I in FIG. 6;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

(Schematic configuration of industrial robot)
First, with reference to FIGS. 1 and 2, the outline of the configuration of an industrial robot 1 according to an embodiment of the present invention will be described. FIG. 1 is a front view of an industrial robot 1 according to an embodiment of the invention. 2(A) is a perspective view of the industrial robot 1 shown in FIG. 1, and FIG. 2(B) is a perspective view showing how the industrial robot 1 shown in FIG. 2(A) operates.

As shown in FIGS. 1 and 2, an industrial robot 1 (hereinafter also referred to as "robot 1") of this embodiment is a multi-joint robot used for assembling and manufacturing predetermined products, and is used in assembly lines and manufacturing lines. installed and used. The robot 1 of this embodiment includes multiple joints 2 and 3 and multiple arms 4 connected to the multiple joints 2 and 3 . In this embodiment, the robot 1 has six joints 2 and 3 and two arms 4 .

In the following description, when each of the six joints 2 and 3 is separately represented, three of the six joints 2 and 3 arranged on the base end side of the robot 1 are referred to as the "second joints." The type 2 joint part 2" and the three parts arranged on the tip side thereof are called the "first type joint part 3". Further, each of the "second type joints 2" is also referred to as "first joint 2A", "second joint 2B" and "third joint 2C" in order from the base end side of the robot 1. Each of the "first type joints 3" is also referred to as "fourth joint 3A", "fifth joint 3B" and "sixth joint 3C" in order from the base end side of the robot 1. Further, in the following description, when each of the two arms 4 is distinguished, each of the two arms 4 will be referred to as "first arm 4A" and "second arm 4B" in order from the base end side of the robot 1. ”.

Further, the robot 1 further includes a support member 5 that is connected to the first joint portion 2A so as to be relatively rotatable. The support member 5 has a flanged cylindrical shape with a flange portion 5a. A through hole (not shown) is formed in the inner peripheral side of the support member 5 so as to extend through the support member 5 in the axial direction. The flange portion 5a is formed in an annular shape, and constitutes a bottom portion as a base of the robot 1. As shown in FIG. The support member 5 is firmly connected and fixed to a fixed surface such as the ground or ceiling surface in the production factory via the flange portion 5a. Also, the arm 4 is formed in an elongated cylindrical shape.

In the robot 1, the first joint portion 2A and the second joint portion 2B are connected so as to be relatively rotatable, and the second joint portion 2B and the base end of the first arm 4A are fixed. Further, the tip of the first arm 4A and the third joint portion 2C are fixed, and the third joint portion 2C and the fourth joint portion 3A are connected so as to be relatively rotatable. Further, the fourth joint portion 3A and the proximal end of the second arm 4B are connected so as to be relatively rotatable, the distal end of the second arm 4B and the fifth joint portion 3B are fixed, and the fifth joint portion 3B and the sixth joint portion 3B are fixed. 3 C of joint parts are connected so that relative rotation is possible. A hand, a tool, or the like can be attached to the sixth joint portion 3C so as to be relatively rotatable.

That is, the robot 1 of this embodiment employs a serial link structure, the fourth joint portion 3A, the fifth joint portion 3B, and the sixth joint portion 3C are arranged on the tip side of the robot 1, and the sixth joint portion 3C is arranged on the most distal side. The first joint portion 2A, the second joint portion 2B, and the third joint portion 2C are arranged on the proximal side of the robot 1, and the first joint portion 2A is arranged on the most proximal side. In addition, due to the joint configuration of the robot 1 described above, the first joint portion 2A, the second joint portion 2B, and the third joint portion 2C are three-dimensional positions (in other words, The joint part 2 mainly determines the position among the positions and orientations. The fourth joint portion 3A, the fifth joint portion 3B and the sixth joint portion 3C are the joint portions 3 connected to the distal end side of the second arm 4B.

Here, in this embodiment, each of the joints 2 and 3 is configured as a rotary actuator including the motor 10 as described below. Rotation restriction mechanisms 30 and 70 for restricting rotation of the motors 10 are mounted on the joints 2 and 3, respectively. Two types of mechanisms are employed as the rotation restricting mechanisms 30 and 70. The first rotation restricting mechanism 30 is of the pin contact type, and the second rotation restricting mechanism 70 is of the electromagnetic type. A second rotation restricting mechanism 70 is mounted on the second type joint portion 2 of the first joint portion 2A, the second joint portion 2B and the third joint portion 2C. A first rotation restricting mechanism 30 is mounted on the first type joint portion 3 of the joint portion 3C.

Specific configurations of the first type joint portion 3 and the second type joint portion 2 will be further described below. As shown in FIG. 1, in this embodiment, the first joint portion 2A, the second joint portion 2B, and the third joint portion 2C in the second joint portion 2 are formed to have the same size, and the first joint portion 2C is formed to have the same size. In the portion 3, the fourth joint portion 3A, the fifth joint portion 3B, and the sixth joint portion 3C are formed with the same size. Also, the sizes of the first joint portion 2A, the second joint portion 2B, and the third joint portion 2C are provided larger than the sizes of the fourth joint portion 3A, the fifth joint portion 3B, and the sixth joint portion 3C. . That is, the second type joint part 2 is larger than the first type joint part 3 . However, the first joint portion 2A, the second joint portion 2B and the third joint portion 2C and the fourth joint portion 3A, the fifth joint portion 3B and the sixth joint portion 3C are different in size and rotation control mechanism 30, They are constructed similarly except that 70 is different. First, the configuration of the first type joint portion 3 will be described.

(Structure of first type joint)
Next, with reference to FIGS. 3 to 5, configurations of the first type joint portion 3, that is, the fourth joint portion 3A, the fifth joint portion 3B, and the sixth joint portion 3C on which the first rotation restricting mechanism 30 is mounted. A specific description will be given. FIG. 3 is a longitudinal sectional view of the first type joint portion 3 shown in FIG. 4A and 4B are enlarged views for explaining the configuration of the G portion shown in FIG. 3, and FIG. 4(B) is an enlarged view showing a state in which the regulation pin 32 is in the regulation position. 5 is a plan view of the rotation-side regulating member 31 and the regulating pin 32 shown in FIG. 3. FIG.
In the following description, for convenience of explanation, the Z1 direction side in FIG. 3 will be referred to as the "upper" side, and the Z2 direction side, which is the opposite side, will be referred to as the "lower" side. In addition, the X1 direction side in FIG. 3 is defined as the "left" side, and the opposite X2 direction side is defined as the "right" side.

As shown in FIG. 3, the first type joint 3 includes a motor 10, a speed reducer 20 connected to the motor 10, a position detection mechanism 60 (detector) for detecting the rotational position of the motor 10, A circuit board B to which the motor 10 and the position detection mechanism 60 are electrically connected, and a case body 80 (housing) that houses the motor 10, the speed reducer 20, the position detection mechanism 60, and the circuit board B. The first type joint portion 3 itself is configured as a rotary actuator.

The motor 10 is a hollow motor with a through hole formed in the center in the radial direction, and includes a hollow magnet holder 12 . Also, the motor 10 includes a rotor 11 and a stator 14 . Further, the speed reducer 20 is a hollow speed reducer having a through hole formed in the center in the radial direction. The motor 10 and the speed reducer 20 are arranged to overlap each other in the vertical direction. Specifically, the motor 10 is arranged on the upper side, and the speed reducer 20 is arranged on the lower side. Also, the motor 10 and the speed reducer 20 are coaxially arranged.

The speed reducer 20 of this embodiment is a hollow wave gear device, and includes a rigid internal gear 21 , a flexible external gear 22 , a wave generator 23 , and a cross roller bearing 26 . The wave generator 23 includes a hollow input shaft 24 connected to the magnet holder 12 of the motor 10 and an elastic bearing 25 attached to the outer peripheral side of the input shaft 24 . In this embodiment, the rigid internal gear 21 serves as the output shaft of the speed reducer 20 .

Further, the first type joint portion 3 is inserted through a first rotation restricting mechanism 30 that restricts the rotation of the stopped rotor 11, the magnet holder 12 of the motor 10, and the input shaft 24 of the speed reducer 20. and an output-side member 18 fixed to the rigid internal gear 21 . The first rotation restricting mechanism 30 and the rotating shaft 17 are similarly housed in the case body 80 .

The motor 10 includes the rotor 11, the stator 14, and the rotary shaft 17, as described above. The rotor 11 includes a magnet holder 12 and a driving magnet 13 fixed to the magnet holder 12 . The magnet holder 12 is integrally fixed to the rotating shaft 17 of the motor 10 and fixes the driving magnet 13 . The magnet holder 12 is formed in a generally cylindrical shape elongated in the vertical direction, and is arranged so that the axial direction of the magnet holder 12 is aligned with the vertical direction. That is, the vertical direction is the axial direction of the magnet holder 12 and the axial direction of the rotor 11 . The driving magnet 13 is formed in a cylindrical shape. The length (length in the vertical direction) of the driving magnet 13 is set shorter than that of the magnet holder 12 , and the driving magnet 13 is fixed to the outer peripheral surface of the lower end portion of the magnet holder 12 .

The stator 14 is formed in a substantially cylindrical shape as a whole, and is arranged on the outer peripheral side (outside in the radial direction) of the driving magnet 13 so as to cover the outer peripheral surface of the driving magnet 13 . The upper end side portion of the magnet holder 12 protrudes upward from the upper end surface of the stator 14 . The stator 14 includes a drive coil (not shown) and a stator core (not shown) having a plurality of salient poles around which the drive coil is wound via insulators. The salient poles of the stator core are formed so as to protrude toward the inner peripheral side, and the tip surfaces of the salient poles face the outer peripheral surface of the drive magnet 13 . Motor 10 is fixed to case body 80 . Specifically, the outer peripheral surface of the stator 14 is fixed to the case body 80 .

The speed reducer 20 includes the rigid internal gear 21, the flexible external gear 22, the wave generator 23, and the cross roller bearing 26, as described above. The rigid internal gear 21 is formed in a flat, substantially cylindrical shape, and is arranged so that the axial direction of the rigid internal gear 21 coincides with the vertical direction. That is, the vertical direction is the axial direction of the rigid internal gear 21 that is the output shaft of the speed reducer 20 . The rigid internal gear 21 is fixed to an inner ring 26 a of a cross roller bearing 26 . The outer ring 26b of the cross roller bearing 26 is fixed to the lower end portion of the case body 80, and the rigid internal gear 21 is rotatably held by the lower end portion of the case body 80 via the cross roller bearing 26. there is

The flexible external gear 22 has a flange portion 22a at its upper end and is formed in a substantially cylindrical shape with a flange. The flange portion 22 a is formed in a substantially annular shape, and the outer peripheral portion of the flange portion 22 a is fixed to the case body 80 . That is, the speed reducer 20 is fixed to the case body 80 . Further, the rigid internal gear 21 constitutes the lower end side portion of the speed reducer 20 . A flange portion 22 a of the flexible external gear 22 constitutes an upper end portion of the speed reducer 20 . Internal teeth are formed on the inner peripheral surface of the rigid internal gear 21 . External teeth that mesh with the internal teeth of the rigid internal gear 21 are formed on the outer peripheral surface of the flexible external gear 22 on the lower end side.

The wave generator 23 has the input shaft 24 and the wave bearing 25 as described above. The input shaft 24 is formed in a cylindrical shape elongated in the vertical direction as a whole, and is arranged so that the axial direction of the input shaft 24 coincides with the vertical direction. A portion of the input shaft 24 other than the lower end portion is formed in an elongated, substantially cylindrical shape. The lower end portion of the input shaft 24 has a circular inner peripheral surface when viewed from the axial direction of the input shaft 24, and an outer peripheral surface having a circular shape when viewed from the axial direction of the input shaft 24. The elliptical portion 24a has an elliptical shape.

The upper end portion of the input shaft 24 of the wave generator 23 is inserted into and fixed to the inner peripheral side of the lower end portion of the magnet holder 12 of the motor 10 . Specifically, the upper end portion of the input shaft 24 is inserted into and fixed to the inner peripheral side of the portion of the magnet holder 12 to which the driving magnet 13 is fixed. The magnet holder 12 and the input shaft 24 are arranged coaxially. Further, the upper end portion of the input shaft 24 is fixed to the magnet holder 12 by adhesion.

A center portion of the input shaft 24 in the vertical direction is rotatably supported by the bearing 16 . Bearing 16 is a ball bearing. This bearing 16 is attached to the bearing holding member 15 , and the bearing holding member 15 is fixed to the case body 80 . That is, the input shaft 24 is rotatably supported by the bearing 16 attached to the case body 80 via the bearing holding member 15 . The bearing holding member 15 is formed in an annular flat plate shape, and is fixed to the case body 80 so as to overlap the flange portion 22a of the flexible external gear 22 in the vertical direction.

Wave bearing 25 is a ball bearing with a flexible inner ring (not shown) and an outer ring (not shown). The wave bearing 25 is arranged along the outer peripheral surface of the elliptical portion 24a and bent in an elliptical shape. The lower end portion of the flexible external gear 22 where the external teeth are formed is arranged on the outer peripheral side of the wave bearing 25 so as to surround the wave bearing 25, and this portion is bent in an elliptical shape. The external teeth of the flexible external gear 22 mesh with the internal teeth of the rigid internal gear 21 at two locations in the longitudinal direction of the lower end portion of the flexible external gear 22 that bends in an elliptical shape. .

The output side member 18 has a flange portion 18a and a cylinder portion 18b and is formed in a substantially cylindrical shape with a flange. The output side member 18 is arranged so that the axial direction of the output side member 18 is aligned with the vertical direction. ing. The flange portion 18a is formed in a flat and annular shape and is connected to the lower end of the cylindrical portion 18b. The flange portion 18 a is fixed to the rigid internal gear 21 so that the upper surface of the flange portion 18 a contacts the lower surface of the rigid internal gear 21 . Further, the flange portion 18 a is arranged below the lower end of the case body 80 and outside the case body 80 .

A small diameter portion 18d having an outer diameter smaller than that of the lower end portion of the cylindrical portion 18b is formed on the upper end side of the cylindrical portion 18b. An annular step surface 18e is formed. The small diameter portion 18d is inserted into the inner peripheral side of the lower end portion of the rotating shaft 17, and the lower end surface of the rotating shaft 17 faces the stepped surface 18e. Further, the through hole 18 c communicates with the inner peripheral side of the rotating shaft 17 . The upper end portion of the cylindrical portion 18b is arranged on the inner peripheral side of the lower end portion of the input shaft 24 of the speed reducer 20 . A bearing 19 is arranged between the outer peripheral surface of the cylindrical portion 18b and the inner peripheral surface of the lower end portion of the input shaft 24. As shown in FIG. Bearing 19 is a ball bearing.

The rotating shaft 17 is configured as a rotating shaft of the motor 10 and is rotationally driven via the magnet holder 12 . The rotating shaft 17 is formed in a vertically elongated cylindrical shape, and is arranged so that the axial direction of the rotating shaft 17 is aligned with the vertical direction. As described above, the rotary shaft 17 is inserted through the inner peripheral sides of the magnet holder 12 and the input shaft 24 . The upper end surface of the rotating shaft 17 is arranged above the upper end surface of the magnet holder 12 , and the lower end surface of the rotating shaft 17 is arranged above the lower end surface of the input shaft 24 . Further, as described above, the small diameter portion 18d of the output side member 18 is inserted into the inner peripheral side of the lower end portion of the rotating shaft 17, and the lower end surface of the rotating shaft 17 faces the stepped surface 18e. A lower end side of 17 is held by an output side member 18 .

The upper end side of the rotating shaft 17 is held by a holding member 50 . The holding member 50 is fixed to the support 51 , and the support 51 is fixed to the case body 80 . That is, the holding member 50 is fixed to the case body 80 via the struts 51 . The holding member 50 has a cylindrical holding portion 50 a that holds the upper end side of the rotating shaft 17 . The holding portion 50a is arranged such that the axial direction of the holding portion 50a is aligned with the vertical direction, and a through hole 50b is formed through the holding portion 50a in the vertical direction on the inner peripheral side of the holding portion 50a.

A large-diameter portion 50c having an inner diameter larger than that of the upper end of the holding portion 50a is formed at the lower end of the holding portion 50a. An annular step surface 50d is formed. The upper end side of the rotating shaft 17 is inserted into the inner peripheral side of the large diameter portion 50c, and the upper end surface of the rotating shaft 17 faces the stepped surface 50d. Further, the through hole 50 b communicates with the inner peripheral side of the rotating shaft 17 .

The position detection mechanism 60 is arranged above the stator 14 of the motor 10 . This position detection mechanism 60 includes a slit plate 61 fixed to the upper end side of the magnet holder 12 and a sensor 62 . The sensor 62 is a transmissive optical sensor that includes a light-emitting element and a light-receiving element that are arranged to face each other. The sensor 62 is fixed to the fixed member 35 as an encoder holder.

The fixing member 35 is fixed to the case body 80 . That is, the sensor 62 is fixed to the case body 80 via the fixing member 35 . The slit plate 61 of the position detection mechanism 60 is formed in a thin flat plate shape and in an annular shape. A plurality of slit holes (not shown) are formed in the slit plate 61 at regular intervals in the circumferential direction of the slit plate 61 . The slit plate 61 is fixed to the magnet holder 12 of the motor 10 so that a portion of the slit plate 61 in the circumferential direction is arranged between the light emitting element and the light receiving element of the sensor 62 .

The case body 80 includes a case body 81 with openings at both upper and lower ends, and a cover 82 that closes the upper end side opening of the case body 81 . The lower end side opening of the case main body 81 is closed by the speed reducer 20 . The side surface of the case main body 81 is formed with an opening 81a that opens in a direction perpendicular to the vertical direction. That is, the case body 80 is formed with an opening 81a that opens in a direction perpendicular to the vertical direction. The opening 81a is formed so as to pass through the side portion of the case main body 81 .

A through-hole 82a in which a pin 43, which constitutes the driving mechanism 40 of the first rotation restricting mechanism 30 described later, is arranged is formed in the upper surface portion of the cover 82. As shown in FIG. That is, the case body 80 is formed with a through hole 82a. The through hole 82a is formed so as to penetrate the upper surface portion of the cover 82 in the vertical direction, and the inside and the outside of the case body 80 communicate through the through hole 82a. Moreover, the through hole 82a is formed in a substantially round hole shape.

As shown in FIGS. 3 and 4, the first rotation restricting mechanism 30 is provided in the first type joint portion 3 to hold the stopped rotor 11 at its stop position. Contained. The first rotation restricting mechanism 30 engages a plate-shaped and substantially annular rotation restricting member 31 (first rotating body) with the rotation restricting member 31 to prevent rotation of the rotation restricting member 31 in the circumferential direction. It includes a regulation pin 32 (first member) that regulates the movement of the side regulation member 31 and a drive mechanism 40 that moves the regulation pin 32 vertically along the axial direction of the rotor 11 . That is, the first rotation regulating mechanism 30 of this embodiment is regulated between a plurality of protrusions 31a (protrusions) described below formed on the outer peripheral portion of the rotation-side regulating member 31 supported by the magnet holder 12 of the motor 10. It is a mechanism that restricts the rotation of the motor 10 by inserting the pin 32 .

The drive mechanism 40 has a compression coil spring 42 as a biasing member that biases the regulation pin 32 upward, and a solenoid 41 that moves the regulation pin 32 downward via a plunger 41a.

The solenoid 41 is fixed to the case body 80 so that the plunger 41a of the solenoid 41 protrudes downward when the solenoid 41 is energized. The upper end (the other end) of the plunger 41 a protrudes above the main body 41 b of the solenoid 41 . The plunger 41a of the solenoid 41 moves the regulation pin 32 along the axial direction of the rotor 11 to a regulation release position, which will be described later, by contacting and pressing the regulation pin 32 with the lower end (one end) of the plunger 41a. . A pin 43 is fixed to the upper end portion of the plunger 41a protruding upward from the body portion 41b.

The pin 43 has a cylindrical shaft portion 43a and an annular flange portion 43b extending radially outward from one end of the shaft portion 43a, and is formed in a cylindrical shape with a flange. That is, the pin 43 is fixed to the upper end portion of the plunger 41a so that the axial direction of the pin 43 is aligned with the vertical direction, and the flange portion 43b is arranged on the lower side. Further, the pin 43 is arranged coaxially with the plunger 41a. A shaft portion 43 a of the pin 43 is arranged in the through hole 82 a of the case body 80 . The outer diameter of the shaft portion 43a is set slightly smaller than the inner diameter of the through hole 82a.
The lower surface of the flange portion 43b of the pin 43 is formed with a recess into which the upper end portion of the plunger 41a is inserted and fixed.

As shown in FIG. 3, the rotation-side regulating member 31 is fixed to the upper end surface of the magnet holder 12 of the rotor 11 so that the thickness direction of the rotation-side regulating member 31 is aligned with the vertical direction. It is arranged above 60. As shown in FIG. 5 , on the outer peripheral surface of the rotation-side regulating member 31 , a plurality of projections 31 a projecting radially outward of the rotation-side regulating member 31 are formed along the circumferential direction of the rotation-side regulating member 31 . are formed at intervals of In this embodiment, 12 protrusions 31a are formed at a pitch of 30° with respect to the center of rotation-side regulating member 31 . In addition, the protrusion 31a is formed to have a substantially isosceles trapezoidal shape when viewed in the vertical direction.
The number of protrusions 31a formed on the rotation-side regulating member 31 is not particularly limited, and may be 11 or less, or 13 or more.

As shown in FIGS. 3 and 4, the restricting pin 32 is a cylindrical member having a uniform cross-sectional shape perpendicular to the axial direction (vertical direction) of the rotor 11. are arranged so that the The regulating pin 32 is fixed to a plunger 41 a arranged above the regulating pin 32 . Specifically, the regulation pin 32 is fixed in contact with the lower end of the plunger 41a.

As shown in FIG. 4, the lower end surface of the regulating pin 32 is formed with a concave portion 32a that is recessed upward, and the upper end portion of the compression coil spring 42 of the drive mechanism 40 is arranged in the concave portion 32a. It is In addition, in this embodiment, the restricting pin 32 is formed in a columnar shape, but is not limited to this.

The regulating pin 32 is arranged on the outer peripheral side of the rotation-side regulating member 31 when viewed in the vertical direction. Specifically, as shown in FIG. 5 , when viewed from above and below, a portion of the regulating pin 32 is more inclined than the virtual circle VC connecting the tip surfaces of the plurality of projections 31 a of the rotation-side regulating member 31 . A regulating pin 32 is arranged so as to be arranged radially inside the side regulating member 31 . As shown in FIGS. 3 and 4, the linear bushing 33 is similarly formed into a columnar shape with a uniform cross-sectional shape perpendicular to the vertical direction, so that the axial direction of the linear bushing 33 is aligned with the vertical direction. are placed in

The linear bushing 33 is entirely inserted into a recess 35a (see FIG. 4) formed in the upper surface of the fixing member 35. As shown in FIG. The lower end surface of the linear bushing 33 is in contact with the bottom surface of the recess 35a. Further, a recess 35b in which the lower end portion of the compression coil spring 42 of the drive mechanism 40 is arranged is formed in the bottom surface of the recess 35a so as to be recessed downward. On the inner peripheral side of the linear bushing 33, the restricting pin 32 is entirely inserted and arranged.

Further, in this embodiment, the solenoid 41 of the drive mechanism 40 is in a non-energized state when the motor 10 is stopped, and is in an energized state when the motor 10 is driven. As shown in FIG. 4B, when the solenoid 41 is not energized, the urging force of the compression coil spring 42 of the driving mechanism 40 causes the regulating pin 32 to be arranged between the protrusions 31a of the rotation-side regulating member 31. , the restricting pin 32 is raised. Therefore, the rotation of the stopped rotor 11 is restricted by the engagement between the protrusion 31 a of the rotation-side restricting member 31 and the restricting pin 32 . On the other hand, when the solenoid 41 is energized, as shown in FIG. 4A, the plunger 41a protrudes downward, and the restriction pin 32 is released from between the protrusions 31a of the rotation-side restriction member 31. Pin 32 descends. Therefore, the rotor 11 becomes rotatable.

In this way, the drive mechanism 40 is configured to have a regulating position (the position shown in FIG. The regulation pin 32 is moved between the regulation release position (the position shown in FIG. 4A) where the regulation pin 32 is removed from the space 31a. Also, the compression coil spring 42 of the drive mechanism 40 biases the regulation pin 32 toward the regulation position. The solenoid 41 moves the regulation pin 32 from the regulation position toward the regulation release position.
When the regulation pin 32 is at the regulation release position, the plunger 41a of the driving mechanism 40 arranged on the outer peripheral side of the rotation-side regulation member 31 is arranged at a position not to contact the protrusion 31a of the rotation-side regulation member 31. .

As shown in FIG. 3, the circuit board B is a rigid board such as a glass epoxy board, and is formed in a flat plate shape. The circuit board B is fixed to the case body 80 so that the thickness direction of the circuit board B is aligned with the vertical direction. Further, the circuit board B is fixed to the upper end side of the case body 80 and arranged above the rotation-side restricting member 31 . The upper end of the rotating shaft 17 is arranged above the upper surface of the circuit board B. As shown in FIG.

A motor drive circuit for driving the motor 10 and a signal transmission circuit for outputting a signal input to the circuit board B to the outside of the circuit board B are mounted on the circuit board B. FIG. At least two connectors are mounted on the circuit board B. As shown in FIG. A wire connected to one of the two connectors is routed so as to pass through the inner peripheral side of the rotating shaft 17 and then pulled out from the through hole 18 c of the output side member 18 . The wiring to be connected to the other connector is pulled out from the opening 81 a of the case body 80 .

(Structure of second type joint)
Next, referring to FIGS. 6 to 8, configurations of the second type joint portion 2, that is, the first joint portion 2A, the second joint portion 2B, and the third joint portion 2C on which the second rotation restricting mechanism 70 is mounted. A specific description will be given. FIG. 6 is a longitudinal sectional view of the first joint portion 2A, the second joint portion 2B and the third joint portion 2C shown in FIG. 7 is a cross-sectional view taken along line HH of FIG. 6. FIG. 8 is a view in the direction of arrow I in FIG. 6. FIG.
In the following description, for convenience of explanation, the Z1 direction side in FIG. 6 is referred to as the "upper" side, and the Z2 direction side, which is the opposite side, is referred to as the "lower" side, as in FIG. In addition, the X1 direction side in FIG. 6 is the "left" side, and the opposite X2 direction side is the "right" side. In addition, the Y1 direction side in FIGS. 7 and 8 is defined as the "rear" side, and the Y2 direction side, which is the opposite side, is defined as the "front" side.

As shown in FIG. 6, the second type joint section 2 includes a motor 10, a speed reducer 20 connected to the motor 10, a position detection mechanism 60 for detecting the rotational position of the motor 10, the motor 10 and the position A circuit board B to which the detection mechanism 60 is electrically connected, and a case body 80 that houses the motor 10, the speed reducer 20, the position detection mechanism 60, and the circuit board B. It is itself configured as a rotary actuator. In addition, the second type joint portion 2 is inserted through the second rotation restricting mechanism 70 that restricts the rotation of the stopped rotor 11, the magnet holder 12 of the motor 10, and the input shaft 24 of the speed reducer 20. and an output-side member 18 fixed to the rigid internal gear 21 . The motor 10 and the second rotation restricting mechanism 70 are accommodated in the case body 80 in the same manner as the first type joint portion 3 .
The second mold joint 2 has a second rotation restricting mechanism 70 in place of the first rotation restricting mechanism 30 of the first mold joint 3, and parts other than the second rotation restricting mechanism are the first mold joints. It is configured in the same manner as the joint section 3 . Therefore, in the configuration of the second type joint portion 2, the same or equivalent parts as those of the first type joint portion 3 are denoted by the same or equivalent reference numerals in the drawings, and the description thereof is omitted or simplified.

The second rotation restricting mechanism 70 is provided in the second type joint section 2 to hold the stopped rotor 11 at its stop position, and is accommodated in the case body 80 (housing). Unlike the first rotation restricting mechanism 30, the second rotation restricting mechanism 70 is an electromagnetic brake mechanism, specifically an electromagnetic brake mechanism. Examples of the electromagnetic brake mechanism include a non-excitation operation type and an excitation operation type. . In the second type joint portion 2, the first rotation restricting mechanism 30 is not mounted as described above, and a predetermined space is provided in the vertical direction between the fixed member 35 and the motor 10, and the second rotation restricting mechanism is provided in the space. A mechanism 70 is arranged. The second rotation restricting mechanism 70 is fixed to the lower side of the fixing member 35 . That is, the second type joint portion 2 has a configuration in which the speed reducer 20, the motor 10, the second rotation restriction mechanism 70, and the position detection mechanism 60 are arranged in this order from the torque output direction side. The fixing member 35 of the second type joint part 2 is not provided with the concave portion 35a and the recess 35b shown in FIG.

The second rotation restricting mechanism 70 includes a flat plate-shaped and substantially circular yoke 71 (coil holder), a flat plate-shaped and substantially circular friction plate 72 (second rotor), the friction plate 72 and the magnet holder of the motor 10 . 12 interposed between the friction plate 72 and the magnet holder 12 to restrict the circumferential movement of the friction plate 72 and the magnet holder 12; ), and a movable plate 74 (second member) that restricts the movement of the friction plate 72 in the circumferential direction. That is, the second rotation restricting mechanism 70 restricts the rotation of the motor 10 by the friction force generated by bringing the movable plate 74 into contact with the upper end surface of the friction plate 72 supported by the magnet holder 12 (rotating shaft 17) of the motor 10. It is a regulatory mechanism.

The yoke 71 is fitted and fixed in a circumferential groove formed in the lower end surface of the fixing member 35 in the circumferential direction. placed. The yoke 71 has an accommodation groove 71a formed in the lower end face in the circumferential direction, a substantially annular coil 71b accommodated in the accommodation groove 71a, and a movable plate 74 facing the friction plate 72. and a plurality of biasing springs (not shown).

When the coil 71b is energized, it generates a magnetic force for moving the movable plate 74 upward (in the direction of the rotating shaft of the motor 10). Also, the spring is inserted into a hole provided in the yoke 71 and its lower end is in contact with the movable plate 74 . Further, the gap between the yoke 71 and the rotor 11 (magnet holder 12) of the motor 10 is set to a distance that suppresses the passage of abrasion powder that may be generated by contact between the movable plate 74 and the friction plate 72. FIG. This makes it possible to prevent the friction powder from entering the position detection mechanism 60 side.
Although the spring is not particularly limited, for example, a coil spring can be used.

As shown in FIG. 7 , the outer shape of the hub 73 is formed in a substantially rectangular (polygonal) shape, and the inner shape thereof is formed in an annular shape corresponding to the outer shape of the magnet holder 12 . Further, as shown in FIG. 6, an annular step surface 12a perpendicular to the vertical direction is formed on the outer peripheral side of the middle portion of the magnet holder 12 in the vertical direction. The inner shape of the hub 73 is inserted into the magnet holder 12 , and the lower end surface of the hub 73 faces the stepped surface 12 a of the magnet holder 12 . Thereby, the hub 73 is firmly fixed to the magnet holder 12 .

As shown in FIGS. 6 and 7 , the friction plate 72 is formed with a substantially rectangular (polygonal) hole 72 a corresponding to the outer shape of the hub 73 . A hub 73 is fitted in the substantially rectangular hole 72a. That is, the friction plate 72 is supported by the magnet holder 12 via a hub 73 fitted in the substantially rectangular hole 72a.
In this embodiment, the hole 72a of the friction plate 72 is formed in a substantially rectangular shape, but it is not limited to this. Polygons may be used, and other than rectangles, triangles, pentagons, hexagons, trapezoids, and the like may be used. The hole 72a may be spline-shaped.

As shown in FIG. 6, the movable plate 74 is made of a magnetic material, is inserted into the magnet holder 12, and is interposed between the yoke 71 and the friction plate 72 so as to be movable in the axial direction of the magnet holder 12, that is, in the vertical direction. be The movable plate 74 is arranged between the yoke 71 and the friction plate 72 so as not to rotate in the circumferential direction of the rotating shaft 17 . The movable plate 74 contacts the lower end surface of the yoke 71 when moving upward, and contacts the upper end surface of the friction plate 72 when moving downward. The second rotation regulating mechanism 70 has a configuration in which a connecting body between a hub 73 and a friction plate 72, a movable plate 74, and a yoke 71 are arranged in order from the torque output direction.

Further, in this embodiment, the coil 71b of the yoke 71 of the second rotation restricting mechanism 70 is in a non-energized state when the motor 10 is stopped, and is in an energized state when the motor 10 is driven. Further, when an abnormality occurs during operation of the second type joint portion 2, the coil 71b of the yoke 71 is switched to a non-energized state even when the motor 10 is driven, and the second type joint portion 2 is abnormally stopped. That is, when the coil 71 b of the yoke 71 is not energized, no magnetic force is generated, and the biasing force of the spring of the yoke 71 causes the movable plate 74 to move downward and contact the friction plate 72 . Due to this contact, the friction plate 72 is restricted from moving in the circumferential direction, and as a result, the rotation of the rotor 11 is restricted. On the other hand, when the yoke 71 is energized, a magnetic force is generated to move the movable plate 74 upward against the biasing force of the spring. Due to this movement, the contact state between the friction plate 72 and the movable plate 74 is released and a gap is formed. Therefore, the rotor 11 becomes rotatable.

Thus, the second rotation restricting mechanism 70 moves the movable plate 74 between the restricting position where the friction plate 72 and the movable plate 74 are in contact with each other and the restriction release position where the movable plate 74 separates from the friction plate 72. . A spring of the yoke 71 biases the movable plate 74 toward the restricted position. When the coil 71b of the yoke 71 is energized, it moves the movable plate 74 from the regulated position toward the regulated position.

Further, in this embodiment, the second rotation restricting mechanism 70 is mounted on the second type joint portion 2 as described above. The second rotation restricting mechanism 70 is of an electromagnetic type, and has a larger occupied volume and weight than the pin contact type of the first rotation restricting mechanism 30 . Therefore, the case body 80 of the second type joint part 2 is provided larger than the first type joint part 3 . As shown in FIG. 8, a substantially rectangular opening 81b is provided in the upper side of the side surface of the case body 80 of the second die joint 2 (the end in the direction perpendicular to the rotation axis direction of the motor 10). (hole) is formed. The opening 81b is open in a direction perpendicular to the vertical direction, and an electric wire is passed through the opening 81b. In the opening 81b, a reinforcing member 81c extending in the vertical direction is formed in the substantially rectangular front-rear intermediate portion to span the upper edge and the lower edge of the opening 81b. The reinforcing member 81c reinforces the strength of the opening 81b.

(Connecting structure of first type joint, second type joint and arm)
With reference to FIG. 2 again, the connecting structure of the second type joint 2, the first type joint 3 and the arm 4 of the robot 1 according to this embodiment will be described.

As described above, the support member 5 and the first joint portion 2A are connected so as to be relatively rotatable, and the first joint portion 2A and the second joint portion 2B are connected so as to be relatively rotatable. Further, the second joint portion 2B and the proximal end of the first arm 4A are fixed, the distal end of the first arm 4A and the third joint portion 2C are fixed, and the third joint portion 2C and the fourth joint portion 3A are fixed. It is connected so that relative rotation is possible. Further, the fourth joint portion 3A and the proximal end of the second arm 4B are connected so as to be relatively rotatable, the distal end of the second arm 4B and the fifth joint portion 3B are fixed, and the fifth joint portion 3B and the sixth joint portion 3B are fixed. 3 C of joint parts are connected so that relative rotation is possible. Specifically, for example, the joints 2 and 3 and the arm 4 are connected as follows so that the robot 1 can perform the motion shown in FIG. 2(B).

In the following description, the axial direction of the rigid internal gear 21 of the first joint portion 2A is defined as "the axial direction of the first joint portion 2A", and the axial direction of the rigid internal gear 21 of the second joint section 2B is defined as " "the axial direction of the second joint portion 2B". Further, the axial direction of the rigid internal gear 21 of the third joint portion 2C is defined as "the axial direction of the third joint portion 2C", and the axial direction of the rigid internal gear 21 of the fourth joint portion 3A is defined as "the fourth joint portion 3A". "axis direction". Further, the axial direction of the rigid internal gear 21 of the fifth joint portion 3B is defined as the “axial direction of the fifth joint portion 3B”, and the axial direction of the rigid internal gear 21 of the sixth joint portion 3C is defined as the “sixth joint portion 3C”. "axis direction".

First, the support member 5 and the first joint portion 2A are connected by fixing the end surface of the support member 5 on the side where the flange portion 5a is not formed to the flange portion 18a of the first joint portion 2A. there is That is, the support member 5 and the first joint portion 2A are connected so that the axial direction of the first joint portion 2A and the axial direction of the support member 5 are aligned. The first joint portion 2A and the second joint portion 2B are connected so that the axial direction of the first joint portion 2A and the axial direction of the second joint portion 2B are orthogonal. A side surface of the case main body 81 of the first joint portion 2A having the opening 81b is fixed to the flange portion 18a of the second joint portion 2B.

The second joint portion 2B and the first arm 4A are connected so that the axial direction of the second joint portion 2B and the longitudinal direction (axial direction) of the first arm 4A are orthogonal. Further, the proximal end of the first arm 4A is fixed to the side surface of the case main body 81 of the second joint portion 2B where the opening 81b is formed. The first arm 4A and the third joint portion 2C are connected so that the longitudinal direction of the first arm 4A and the axial direction of the third joint portion 2C are orthogonal. Further, the tip of the first arm 4A is fixed to the side surface of the case main body 81 of the third joint 2C where the opening 81b is formed.

The third joint portion 2C and the fourth joint portion 3A are connected so that the axial direction of the third joint portion 2C and the axial direction of the fourth joint portion 3A are orthogonal. Further, the side surface of the case main body 81 of the fourth joint portion 3A, in which the opening portion 81a is formed, is fixed to the flange portion 18a of the third joint portion 2C. More specifically, the fourth joint portion is attached to the flange portion 18a of the third joint portion 2C via the connecting member 6 fixed to the side surface of the case main body 81 of the fourth joint portion 3A where the opening portion 81a is formed. The side surface of the case main body 81 of 3A on which the opening 81a is formed is fixed. The connecting member 6 has a flanged cylindrical shape with a flange portion 5a fixed to the flange portion 18a of the third joint portion 2C.

The fourth joint portion 3A and the second arm 4B are connected so that the axial direction of the fourth joint portion 3A and the longitudinal direction of the second arm 4B are aligned. Also, the proximal end of the second arm 4B is fixed to the flange portion 18a of the fourth joint portion 3A.
A flange portion 4a for fixing the proximal end of the second arm 4B to the flange portion 18a of the fourth joint portion 3A is formed at the proximal end of the second arm 4B. The portion 18a and the flange portion 4a are fixed to each other.

The second arm 4B and the fifth joint portion 3B are connected so that the longitudinal direction of the second arm 4B and the axial direction of the fifth joint portion 3B are orthogonal. Further, the tip of the second arm 4B is fixed to the side surface of the case main body 81 of the fifth joint 3B where the opening 81a is formed. The fifth joint portion 3B and the sixth joint portion 3C are connected so that the axial direction of the fifth joint portion 3B and the axial direction of the sixth joint portion 3C are orthogonal. Further, the side surface of the case body 81 of the sixth joint portion 3C, in which the opening portion 81a is formed, is fixed to the flange portion 18a of the fifth joint portion 3B.

By connecting the first type joint part 3, the second type joint part 2 and the arm 4 in this way, the second type joint part 2 supports the second arm 4B and the first type joint part 3. The output torque (required torque) of the first joint portion 2A, the second joint portion 2B, and the third joint portion 2C of the second type joint portion 2 is large. On the other hand, unlike the second type joint portion 2, the first type joint portion 3 does not have a mechanism that requires support attached to its distal end side. The required torque of the joint portion 3B and the sixth joint portion 3C may be smaller than that of the second type joint portion 2. That is, among the six joint portions 2 and 3, the joint portions 2 and 3 whose output torque is equal to or less than the threshold are the fourth joint portion 3A, the fifth joint portion 3B and the sixth joint portion 3C of the first type joint portion 3. be. The joint portions 2 and 3 whose output torque exceeds the threshold are the first joint portion 2A, the second joint portion 2B and the third joint portion 2C of the second type joint portion 2, respectively.

(Main effects of this form)
As described above, in this embodiment, the plurality (six in this embodiment) of the joints 2 and 3 are the first type joints including the motor 10 and the first rotation restricting mechanism 30 that restricts the rotation of the motor 10. 3, and a second type joint 2 including a motor 10 and a second rotation restricting mechanism 70 that restricts the rotation of the motor 10. The first rotation regulating mechanism 30 includes a regulating pin 32 between a plurality of protrusions 31a (protrusions) formed on the outer peripheral portion of a rotation-side regulating member 31 (first rotating body) supported by the rotating shaft 17 of the motor 10. It is a mechanism for restricting the rotation of the motor 10 by inserting (the first member). The second rotation restricting mechanism 70 is configured by bringing a movable plate 74 (second member) into contact with the end surface of the friction plate 72 (second rotating body) supported by the rotating shaft 17 of the motor 10 in the direction of the rotating shaft 17. It is a mechanism that regulates the rotation of the motor 10 by the generated frictional force.

Two types of rotation restricting mechanisms 30, 70 having different stopping or braking mechanisms and characteristics are used in combination with a small and lightweight first rotation restricting mechanism 30 and a second rotation restricting mechanism 70 with large brake torque and high durability. The robot 1 is configured including As a result, the rotation restricting mechanisms 30, 30, 30, 30, 300, 300, 300, 300, 300, 300, 300, 300, 300, 300, 300, 300, 300, 300, and 300 can be controlled according to the positions of the joints 2, 3 according to the required torque of the joints 2, 3 of the robot 1, and the characteristics and balance of the robot 1 as a whole, such as its overall size and weight. By appropriately selecting the type of 70, the entire robot 1 can be optimized in terms of stopping and braking the joints 2 and 3. FIG. That is, a regulation mechanism suitable for each position of the joints 2 and 3 can be introduced, and both durability improvement and workability improvement of the robot 1 can be achieved.

Further, in this embodiment, among the plurality of joints 2, 3, the joints 2, 3 arranged on the most distal side are the first type joints 3 (first joints) having the first rotation restricting mechanism 30. be. The joint portion located closest to the proximal end is the second type joint portion 2 (second joint portion) having the second rotation restricting mechanism 70 .

Here, in the robot 1 having a plurality of joints 2 and 3 and an arm 4 connected to the joints 2 and 3, the front end side of the robot 1 is generally required to be lightweight. For this reason, the first-type joint part 3 (first joint part) configured to include the compact and lightweight first rotation restricting mechanism 30 is suitable for the joint part 3 arranged on the most distal side. On the other hand, the base end side (base side) of the robot 1 may be fixed to a fixed surface such as a ceiling surface or the ground. . For this reason, the joint portion 2 arranged on the most proximal side is the second type joint portion 2 (second joint portion) that includes the second rotation restricting mechanism 70 with large braking torque and high durability. Are suitable. That is, by appropriately selecting and introducing the rotation restricting mechanisms 30 and 70 according to the position of the robot 1 on the distal end side and the proximal end side, the robot 1 as a whole can be controlled more appropriately from the characteristics and balance of the robot 1 as a whole. can be optimized.

Further, in this embodiment, among the plurality of joints 2 and 3, the joints 2 and 3 for determining the three-dimensional position of the arm 4 arranged on the most distal side are the second type joints 2 (second joints ). The joint portion connected to the distal end side of the arm 4 is the first type joint portion 3 (first joint portion).

Here, in the robot 1 having a plurality of joints 2 and 3 and an arm 4 connected to the joints 2 and 3, the three-dimensional position (mainly the position among the positions and orientations) of the arm 4 on the tip side of the robot 1 is The required torque for determination is generally large. For this reason, the second-type joint 2 (second joint) configured to include the second rotation restricting mechanism 70 with large braking torque and high durability is suitable for the joint 2 for this purpose. On the other hand, since the joint portion 3 connected to the tip side of the arm 4 is mainly for determining the posture, the required torque for determining this posture does not need to be so large. For this reason, the joint 3 connected to the distal end side of the arm 4 is suitable for the first-type joint 3 (first joint) configured to include the small and lightweight first rotation restricting mechanism 30. ing. That is, by appropriately selecting and introducing the rotation restricting mechanisms 30 and 70 in accordance with the degree of contribution to position determination or attitude determination of each arm 4, the robot 1 as a whole can be improved from the characteristics and balance of the robot 1 as a whole. can be properly optimized.

Further, in the present embodiment, among the plurality of joint portions 2 and 3, the joint portion 3 whose output torque is equal to or less than the threshold is the first type joint portion 3 (first joint portion). The joint portion 2 whose output torque exceeds the threshold is the second type joint portion 2 (second joint portion).

Therefore, in the robot 1 having a plurality of joints 2 and 3 and the arm 4 connected to the joints 2 and 3, the rotation restricting mechanisms 30 and 30 are controlled according to the magnitude of the output torque required for each joint 2 and 3. By appropriately selecting and introducing 70, the entire robot 1 can be optimized more appropriately from the characteristics and balance of the robot 1 as a whole.

Moreover, in this embodiment, two arms 4 are included, and six joints 2 and 3 are included as the plurality of joints 2 and 3 . Of the six joints 2 and 3, the three joints 3 arranged on the distal end side are the first type joints 3 (first joints). Each of the three joints 2 arranged on the proximal end side is a second type joint 2 (second joint).

When six joints 2 and 3 are provided as in this embodiment, the three joints 3 arranged on the distal end side do not need to require a large torque, so the compact and lightweight first rotation restricting mechanism 30 A first type joint 3 (first joint) is suitable. On the other hand, the three joints 2 arranged at the proximal end require a larger torque than the three joints 3 at the distal end. Therefore, the three joints 2 arranged at the proximal end are suitable for the second type joints 2 (second joints) configured to include the second rotation restricting mechanism 70 with large braking torque and high durability. ing.

Further, in this embodiment, the second type joint portion 2 (second joint portion) includes a case body 80 (housing) that houses the motor 10 and the second rotation restricting mechanism 70 . An opening 81a (hole) through which an electric wire is passed is provided at the end of the case body 80 in a direction perpendicular to the rotation axis direction of the motor 10, and a reinforcing member 81c for reinforcing the opening 81b is provided in the opening 81b. formed.

Here, when the second rotation restricting mechanism 70 is mounted on a predetermined joint portion 2, the external shape of the joint portion 2 tends to increase, and accordingly the case body 80 (housing) also increases in size. Therefore, with this configuration, even if the second rotation restricting mechanism 70 is mounted and the case body 80 of the joint portion 2 is enlarged, the reinforcing member 81c is formed in the opening 81b for passing the electric wire. The strength of the case body 80 of the joint portion 2 can be increased. As a result, vibration of the robot 1 itself can be suppressed when the robot 1 operates. Note that such a reinforcing member may be provided in an opening provided in the case body 80 of the joint portion 3 for passing an electric wire.

Further, in this embodiment, the second type joint portion 2 (second joint portion) optically detects the rotational positions of the speed reducer 20, the motor 10, the second rotation restricting mechanism 70, and the motor 10 in this order from the torque output direction side. It is a configuration in which a position detection mechanism 60 (detector) that detects the target is arranged. Between the friction plate 72 (second rotating body) of the second rotation restricting mechanism 70 and the position detection mechanism 60, a coil 71b for generating a magnetic force for moving the friction plate 72 in the rotation axis direction of the motor 10 is accommodated. A yoke 71 is provided.

In this manner, the yoke 71 is arranged between the friction plate 72 (second rotating body) of the second rotation restricting mechanism 70 and the position detecting mechanism 60 (detector). Even if friction powder is generated from the friction plate 72 during use, the yoke 71 serves as a barrier to prevent the friction powder from entering the position detection mechanism 60 side. By suppressing this intrusion, it is possible to prevent the operation of the position detection mechanism 60 from being affected.

Further, in this embodiment, the gap between the yoke 71 and the rotor 11 (magnet holder 12) of the motor 10 is the wear that can occur due to contact between the movable plate 74 (second member) and the friction plate 72 (second rotating body). It is a distance that suppresses the passage of powder.

Therefore, since the gap between the yoke 71 and the rotor 11 is set to a distance that suppresses the passage of the friction powder, it is possible to further suppress the friction powder from entering the position detection mechanism 60 (detector) side. can be done.

Further, in this embodiment, the second type joint portion 2 (second joint portion) includes a magnet holder 12 that is fixed to the rotating shaft 17 of the motor 10 and supports the driving magnet 13 of the motor 10 . A substantially rectangular (an example of a polygonal) hole 72a is formed in the friction plate 72 (second rotor) of the second rotation restricting mechanism 70 . The friction plate 72 is supported by the magnet holder 12 via a hub 73 fitted in the substantially rectangular hole 72a.

Therefore, during the assembly and production of the second rotation restricting mechanism 70, it is easy to provide a magnetization process after shrink-fitting and appropriately change the process according to the arrangement order of the constituent members. can do.

(Other embodiments)
The embodiment described above is an example of the preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

In the embodiment described above, the compression coil spring 42 of the first rotation restricting mechanism 30 urges the restricting pin 32 upward, and the solenoid 41 moves the restricting pin 32 downward, but it is not limited to this. For example, the compression coil spring 42 may urge the regulation pin 32 downward, and the solenoid 41 may move the regulation pin 32 upward. Further, in the embodiment described above, the compression coil spring 42 of the first rotation restricting mechanism 30 urges the restricting pin 32, but this is not restrictive. For example, the regulation pin 32 may be biased by another spring member such as a tension coil spring.

In the embodiment described above, the protrusion 31a of the rotation-side regulating member 31 is formed so as to protrude radially outward of the rotor 11, but is not limited to this. For example, the protrusion 31 a may be formed to protrude radially inward of the rotor 11 .

Although the pin 43 is fixed to the upper end portion of the plunger 41a of the drive mechanism 40 in the embodiment described above, the present invention is not limited to this. For example, the pin 43 may not be fixed to the upper end of the plunger 41a. In this case, the length of the upper end portion of the plunger 41a that protrudes upward from the body portion 41b of the solenoid 41 is longer, and the upper end portion of the plunger 41a is arranged in the through hole 82a of the case body 80. ing. When the regulating pin 32 is at the regulating position, the upper end of the plunger 41a protrudes outside the case body 80, and the upper end of the plunger 41a protruding outside the case body 80 extends toward the inside of the case body 80. When pressed, the regulating pin 32 at the regulating position moves to the regulating position.

If the pin 43 is not fixed to the upper end of the plunger 41a of the drive mechanism 40, the upper end of the plunger 41a may be arranged inside the case body 80 when the regulating pin 32 is in the regulating position. In this case, the cover 82 may not have the through hole 82a.

In the embodiment described above, the rigid internal gear 21 serves as the output shaft of the speed reducer 20, but it is not limited to this. For example, the flexible external gear 22 may serve as the output shaft of the speed reducer 20 . In this case, the rigid internal gear 21 is fixed to the case body 80 and the inner ring 26a of the cross roller bearing 26, and the flexible external gear 22 is fixed to the outer ring 26b of the cross roller bearing 26 and the flange portion 18a of the output side member 18. be done. Moreover, although the speed reducer 20 is a hollow wave gear device in the embodiment described above, it is not limited to this. For example, the speed reducer 20 may be a hollow speed reducer other than the hollow wave gear device. Also, the speed reducer 20 may be a speed reducer other than the hollow speed reducer. Moreover, although the motor 10 is a hollow motor in the embodiment described above, it is not limited to this. For example, motor 10 may be a motor other than a hollow motor. Further, although the motor 10 is a so-called inner rotor type motor in the embodiment described above, it is not limited to this. For example, the motor 10 may be an outer rotor type motor.

Although the robot 1 has six joints 2 and 3 in the embodiment described above, it is not limited to this. For example, the number of joints 2 and 3 included in the robot 1 may be five or less, or may be seven or more. Moreover, although the robot 1 is provided with two arms 4 in the form mentioned above, it is not limited to this. For example, the number of arms 4 provided in the robot 1 may be one, or three or more. In addition, in the embodiment described above, the joints 2 and 3 of the robot 1 are configured by rotary actuators having the motor 10 and the speed reducer 20, but the present invention is not limited to this. For example, rotary actuators may be used other than the joints 2 and 3 of the robot 1 . In addition, the rotary actuator may be used as a driving portion of a θ stage (rotational stage). Moreover, although the robot 1 is an industrial robot in the embodiment described above, the robot 1 can be applied to various uses. For example, robot 1 may be a service robot.

1 Industrial robots (robots)
2 Second type joint 2A First joint 2B Second joint 2C Third joint 3 First type joint 3A Fourth joint 3B Fifth joint 3C Sixth joint 4 Arm 4A First arm 4B 2 Arm 4a Flange 5 Supporting member 5a Flange 6 Connecting member 6a Flange 10 Motor 11 Rotor 12 Magnet holder 12a Step surface 13 Driving magnet (magnet)
14 Stator 15 Bearing holding member 16 Bearing 17 Rotating shaft 18 Output side member 18a Flange 18b Cylindrical portion 18c Through hole 18d Small diameter portion 18e Step surface 19 Bearing 20 Reducer 21 Rigid internal gear 22 Flexible external gear 22a Flange 23 Wave motion generating part 24 Input shaft 24a Elliptical part 25 Wave bearing 26 Cross roller bearing 26a Inner ring 26b Outer ring 30 First rotation restricting mechanism 31 Rotation side restricting member (first rotor)
31a projection (projection)
32 Regulating pin (first member)
32a recess 33 linear bushing 35 fixing member 35a recess 35b recess 40 drive mechanism 41 solenoid 41a plunger 41b body portion 42 compression coil spring 43 pin 43a shaft portion 43b flange portion 50 holding member 50a holding portion 50b through hole 50c large diameter portion 50d step surface 51 Post 60 Position detection mechanism (detector)
61 slit plate 62 sensor 70 second rotation restricting mechanism 71 yoke 71a housing groove 71b coil 72 friction plate (second rotor)
72a hole 73 hub 74 movable plate (second member)
80 case body (casing)
81 Case body 81a Opening 81b Opening (hole)
81c reinforcing member 82 cover 82a through hole

Claims (9)

A robot having a plurality of joints and an arm connected to the joints,
The plurality of joints includes at least one first joint including a motor and a first rotation restricting mechanism that restricts rotation of the motor, and at least one including a motor and a second rotation restricting mechanism that restricts rotation of the motor. a second articulation, and
The first rotation restricting mechanism is a mechanism for restricting rotation of the motor by inserting a first member between a plurality of projections formed on an outer peripheral portion of a first rotating body supported by a rotating shaft of the motor. and
The second rotation restricting mechanism restricts rotation of the motor by a frictional force generated by bringing a second member into contact with an end surface of a second rotating body supported by the rotating shaft of the motor in the direction of the rotating shaft. is a mechanism,
The second joint portion has a configuration in which a speed reducer, the motor, the second rotation restriction mechanism, and a detector that optically detects the rotational position of the motor are arranged in order from the torque output direction side,
A coil holder that houses a coil that generates a magnetic force for moving the second member in the rotation axis direction of the motor is provided between the second rotating body of the second rotation restricting mechanism and the detector. Robot . A robot having a plurality of joints and an arm connected to the joints,
The plurality of joints includes at least one first joint including a motor and a first rotation restricting mechanism that restricts rotation of the motor, and at least one including a motor and a second rotation restricting mechanism that restricts rotation of the motor. a second articulation, and
The first rotation restricting mechanism is a mechanism for restricting rotation of the motor by inserting a first member between a plurality of projections formed on an outer peripheral portion of a first rotating body supported by a rotating shaft of the motor. and
The second rotation restricting mechanism restricts rotation of the motor by a frictional force generated by bringing a second member into contact with an end surface of a second rotating body supported by the rotating shaft of the motor in the direction of the rotating shaft. is a mechanism,
The second joint portion includes a magnet holder that is fixed to the rotating shaft of the motor and supports the magnet of the motor,
A polygonal hole is formed in the second rotating body of the second rotation restricting mechanism,
The robot, wherein the second rotating body is fixed to the magnet holder via an attachment that fits into the polygonal hole. The robot according to claim 1 or 2 ,
Among the plurality of joints, the joint closest to the distal end is the first joint, and the joint closest to the proximal end is the second joint. The robot according to claim 1 or 2 ,
Among the plurality of joint portions, the joint portion for determining the three-dimensional position of the arm arranged on the most distal side is the second joint portion, and the joint portion connected to the distal side of the arm is the second joint portion. A robot with one joint. The robot according to claim 1 or 2 ,
Among the plurality of joints, the joint having an output torque equal to or less than a threshold is the first joint, and the joint having an output torque exceeding the threshold is the second joint. The robot according to any one of claims 3 to 5 ,
comprising two said arms;
including six joints as the plurality of joints,
Of the six joints, the three joints arranged on the distal side are the first joints, and the three joints arranged on the proximal side are the second joints. The robot according to any one of claims 1 to 6 ,
the second joint includes a housing that accommodates the motor and the second rotation restricting mechanism,
A hole through which an electric wire is passed is provided at an end of the housing in a direction orthogonal to the rotation axis direction of the motor,
The robot, wherein a reinforcing member is formed in the hole to reinforce the hole. The robot according to claim 1 ,
In the robot, the gap between the coil holder and the rotor of the motor is a distance that suppresses the passage of abrasion powder generated by the contact between the second member and the second rotating body. The robot according to claim 1 ,
The second joint portion includes a magnet holder that is fixed to the rotating shaft of the motor and supports the magnet of the motor,
A polygonal hole is formed in the second rotating body of the second rotation restricting mechanism,
The robot, wherein the second rotating body is fixed to the magnet holder via an attachment that fits into the polygonal hole.

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