WO2023032465A1

WO2023032465A1 - Tool changer

Info

Publication number: WO2023032465A1
Application number: PCT/JP2022/026850
Authority: WO
Inventors: 悠竹林
Original assignee: 株式会社コガネイ
Priority date: 2021-08-30
Filing date: 2022-07-06
Publication date: 2023-03-09
Also published as: JP2023033937A

Abstract

Provided is a tool changer having a simple structure.　This tool changer 10 has: a master unit 11 in which an electric motor 31 is incorporated; a tool unit 12 to which a lock pin 42 is attached, the lock pin 42 protruding toward the master unit 11, and the tool unit 12 being provided with an operation device; a cam member 33 provided with the master unit 11, the cam member 33 being rotationally driven by a shaft 32 of the electric motor 31; and a lock member 47 provided to the master unit 11 so as to be capable of moving in a direction crossing a rotational center axis of the cam member 33. The lock member 47 moves to a lock position for engaging with an engagement groove 56 in the lock pin 42 due to the cam member 33, and an unlock position for being released from the engagement groove 56.

Description

tool changer

The present invention relates to a tool changer to which a tool unit is detachably attached.

A tool exchange device is attached to the robot arm as a moving device in order to operate the robot arm to perform operations such as processing the workpiece. The tool changer has a master unit attached to the robot arm and a tool unit detachably attached to the master unit. The tool unit is provided with manipulating devices such as tools and hands for processing the work and transporting the work and jigs. A plurality of tool units with different operating devices according to the type of operation on the workpiece or jig are arranged on the support base, and one of the tool units is attached to the master unit of the tool changer according to the operation. .

Patent Document 1 describes an opening and closing chuck for a robot hand. This opening/closing chuck has fingers for gripping and moving an article, and the fingers are replaced according to the type of article. A stopper for fixing the finger is provided on the casing, and the finger is fixed by the stopper by the spring force of the spring. When the stopper is pushed manually against the spring force, the finger is released from the stopper and the finger can be replaced.

Patent Document 2 discloses a floating device provided between a robot arm and a replacement tool. This floating device has a fixed plate connected to a robot arm and a driven plate mounted thereon, and a tool plate is detachably mounted on the driven plate. The driven plate is provided with a mounting opening into which the connecting shaft of the tool plate is inserted, and the driven plate is provided with a locking mechanism for locking the connecting shaft inserted into the mounting opening. The lock mechanism includes a hydraulic cylinder and a lock plate. When the actuator of the cylinder is raised, the lock plate is unlocked by the biasing force of the spring, and the tool plate can be separated from the follower plate. On the other hand, when the actuator descends, it engages the groove of the coupling shaft and locks the tool plate.

JP-A-2004-82245 JP-A-63-300885

As in the open/close chuck described in Patent Document 1, if the fingers for gripping the article are manually replaced, it is troublesome for the operator to replace the fingers, and it is not suitable for use in an environment in which the intervention of the operator is not desired. is unsuitable. On the other hand, as described in Patent Literature 2, in a device that drives an actuator with a working fluid, the size of the device is increased, and piping or the like needs to be arranged, making the device complicated.

An object of the present invention is to provide a tool changing device with a simple structure.

A tool changing device of the present invention comprises a master unit in which an electric motor is incorporated, a tool unit provided with an operating device, and a lock pin projecting toward the master unit, and a tool unit provided in the master unit, wherein the electric a cam member that is rotationally driven by a shaft of a motor; and a lock member that is provided on the master unit so as to be movable in a direction transverse to the central axis of rotation of the cam member; It moves to a locked position where it engages with the engagement groove of the lock pin and a release position where it leaves the engagement groove.

The tool changer has a master unit in which an electric motor is incorporated, and a tool unit to which a lock pin projecting toward the master unit is attached. A cam member rotated by the electric motor moves the lock member to the lock pin. The tool unit can be detachably attached to the master unit by means of a tool changing device having a simple structure, since the tool unit can be moved between the lock position where it engages and the release position where it separates from the engagement groove.　

1 is a front view showing the appearance of a tool changing device according to an embodiment having a tool unit to which an electric hand as an operation device is attached and a master unit to which a robot arm is attached; FIG. FIG. 2 is a longitudinal sectional view of the tool changer shown in FIG. 1; FIG. 4 is a cross-sectional view showing the tool changing device with the tool unit removed from the master unit; FIG. 3 is an exploded perspective view of FIG. 2; FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3; FIG. 3 is a cross-sectional view taken along the line BB in FIG. 2, where (A) shows the locked position where the cam member is engaged with the lock pin, and (B) shows the released position where the cam member is separated from the lock pin. 3 is an enlarged cross-sectional view of a portion C in FIG. 2, where (A) shows the locked position of the cam member and (B) shows the released position of the cam member; FIG. FIG. 7 is a cross-sectional view showing the head of the lock pin shown in FIG. 6 with a chain double-dashed line, (A) showing a locked position where the cam member is engaged with the lock pin, and (B) showing the cam member extending from the lock pin. Shows the far release position. FIG. 9 is a cross-sectional view showing the same part as in FIG. 8 in a tool changer according to another embodiment;

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. As shown in FIG. 1 , the tool changing device 10 has a master unit 11 and a tool unit 12 attached to the master unit 11 . The master unit 11 is attached to a robot arm 13 as a moving device. An electric hand 14 as an operating device is attached to the tool unit 12 . A plurality of tool units 12 are arranged on a support table (not shown), and the tool unit 12 corresponding to the work performed by the industrial robot is attached to the master unit 11 by the robot arm 13 .

A connector 15 on the master unit 11 side is provided on the master unit 11 , and a connector 16 on the tool unit 12 side is provided on the tool unit 12 . The connector 15 is connected via a signal line 17 to a controller 18 arranged in the robot controller, and the connector 16 is connected via a signal line 19 to the electric hand 14 . The tool changer 10 moves along a predetermined movement path with the electric hand 14 by the robot arm 13 . The electric hand 14 has two fingers 20 for gripping a workpiece or the like, and the fingers 20 can move toward and away from each other. The electric hand 14 is controlled by a signal from the controller 18 to grip a workpiece or the like by the fingers 20 of the electric hand 14 at a predetermined position and to release the gripped workpiece or the like.

2 to 4 show the tool changer 10 with the master unit 11 separated from the robot arm 13 and the electric hand 14 removed from the tool unit 12 . As shown in FIGS. 2 to 4, the master unit 11 has a cylindrical unit body 22 in which a motor housing chamber 21 is formed, and a support plate 24 attached to the tip surface 23 of the unit body 22. there is As shown in FIGS. 4 and 5, in order to attach the support plate 24 to the unit main body 22, the unit main body 22 is formed with two screw mounting holes 25, and the support plate 24 is screwed in correspondence with the screw mounting holes 25. As shown in FIGS. A screw hole 25a is formed. A bolt 26 as a screw member is inserted into the screw mounting hole 25 from the back side of the unit body 22, and the threaded portion of the bolt 26 is screwed into the screw hole 25a. Thereby, the support plate 24 is fastened to the unit main body 22 .

In order to attach the unit body 22 to the robot arm 13, four screw mounting holes 27 are formed in the unit body 22, and screw mounting holes 27a are formed in the support plate 24 corresponding to the screw mounting holes 27. The head of a bolt 28 as a screw member is arranged in the large-diameter hole on the front side of the screw mounting hole 27a, and as shown in FIG. screwed to. Thereby, the master unit 11 is fastened to the robot arm 13 .

In this way, the support plate 24 is abutted against and fastened to the tip surface 23 of the unit body 22 by the bolts 26, and the tip surface of the support plate 24 faces the tool unit 12, and a mounting surface 29 to which the tool unit 12 is attached. configure. Note that the

respective bolts

26 and 28 are omitted in FIG.

The electric motor 31 is incorporated in the motor housing chamber 21. A shaft 32 of the electric motor 31 protrudes from the tip surface 23 of the unit body 22, and the shaft 32 is connected to a cam member 33 made of an elliptical plate cam. As shown in FIG. 4 , the cam member 33 is arranged in a cam accommodating portion 34 formed in the support plate 24 and driven to rotate about the rotation center axis O of the shaft 32 by the electric motor 31 . In order to transmit the rotation of the shaft 32 to the cam member 33, the cam member 33 is formed with a connecting hole 33a extending in a direction perpendicular to the central axis O of rotation. located at the tip.

As shown in FIGS. 2 and 3, a fitting hole 35 having a tapered portion is formed in the radially central portion of the tool unit 12 , and a fitting portion 36 that fits into the fitting hole 35 is the master unit 11 . The fitting portion 36 protrudes forward from the mounting surface 29 . As shown in FIG. 2, by fitting the fitting portion 36 into the fitting hole 35, the tool unit 12 is centered with respect to the master unit 11 with high accuracy.

A support hole 38 for rotatably supporting a shaft portion 37 provided in the cam member 33 is formed in the fitting portion 36 , and the cam member 33 is rotatably supported in the cam accommodating portion 34 of the support plate 24 . . The shaft portion 37 may be supported in the support hole 38 of the fitting portion 36 via a bearing. As shown in FIG. 4 , the support plate 24 is formed with locking member accommodating portions 39 on both sides of the cam accommodating portion 34 so as to be continuous with the cam accommodating portion 34 .

Four screw holes 41 are formed in the tool unit 12 as shown in FIG. A threaded portion 43 of a lock pin 42 is screwed into each threaded hole 41 as shown in FIGS. The rear surface of the tool unit 12 is an abutment surface 44 that abuts against the mounting surface 29 of the master unit 11 , and the lock pin 42 is provided with a large-diameter portion 45 that contacts the abutment surface 44 . When the threaded portion 43 is screwed into the threaded hole 41 , the large diameter portion 45 is in close contact with the abutment surface 44 . Each lock pin 42 protrudes from an abutment surface 44 of the tool unit 12 , and when the tool unit 12 is attached to the master unit 11 , the protruding portion of each lock pin 42 protrudes from the through hole formed in the support plate 24 . It penetrates through the hole 46 and protrudes into the locking member accommodating portion 39 . The through hole 46 opens into the lock member accommodating portion 39 , and the large diameter portion 45 of the lock pin 42 is inserted into the through hole 46 .

A lock member 47 is arranged in each of the lock member housing portions 39, and the support plate 24 is provided with two lock members 47 so as to face each other. The cam accommodating portion 34 and the lock member accommodating portion 39 are integrally formed by a groove or recess formed in the support plate 24 . Each lock member 47 is movable in the direction of a radial axis R extending perpendicularly to the rotation center axis O of the shaft 32, as shown in FIG. That is, the lock member 47 is movable in a direction crossing the rotation center axis O. As shown in FIG.

FIG. 5 is a cross-sectional view taken along line AA in FIG. 6A and 6B are cross-sectional views along the line BB in FIG. 2, FIG. 6A shows a locked state in which the cam member is engaged with the lock pin, and FIG. Indicates status. 7A and 7B are enlarged cross-sectional views of the portion C in FIG. 2, where FIG. 7A shows the locked position of the cam member and FIG. 7B shows the released position of the cam member.

5, in order to guide movement of the locking member 47, a locking member accommodation portion 39 is formed therebetween by opposing guide surfaces 48, the guide surfaces 48 on both sides of the cam member 33 It continues to the inner surface 52 of the cam accommodating portion 34 having a larger diameter than the outer diameter. The guide surfaces 48 facing each other are connected by an end wall surface 53 forming an end wall of the lock member accommodating portion 39 .

As shown in FIG. 7, each lock pin 42 has a head portion 54, and a small-diameter shaft portion 55 between the head portion 54 and the large-diameter portion 45 allows the lock pin 42 to engage with the lock pin 42 in an engaging groove. 56 is formed. A pin through hole 57 through which the head 54 passes is formed in each lock member 47 .

As shown in FIG. 5, the pin through-hole 57 has a large-diameter arcuate surface 62a having a larger diameter than the head 54 of the lock pin 42 and a small-diameter arcuate surface 62b which is continuous and opposed thereto. The small-diameter arc surface 62b has a radius of curvature corresponding to the outer diameter of the small-diameter shaft portion 55 of the lock pin 42, and is shifted in the moving direction of the lock member 47 with respect to the large-diameter arc surface 62a. The lock member 47 is formed with an arcuate surface 58 facing the large-diameter arcuate surface 62a of the pin through hole 57, and the arcuate surface 58 is offset from the large-diameter arcuate surface 62a in the movement direction of the lock member 47. there is The deviation of the movement direction of the locking member of the small-diameter arc surface 62b from the large-diameter arc surface 62a is greater in the arc surface 58. As shown in FIG. As shown in FIG. 7, the thickness of the circular arc surface 58 in the direction along the rotation center axis O is thinner than the thickness of the lock member 47, and a step surface is formed between the circular arc surface 58 and the pin through hole 57. . This stepped surface forms an engaging portion 59 that contacts the small-diameter shaft portion 55 side of the head portion 54 and engages with the engaging groove 56 . A locking space 61 into which the head portion 54 is inserted is provided between the tip surface 23 of the unit body 22 and the engaging portion 59, as shown in FIG.

FIG. 8 is a cross-sectional view showing the head portion 54 of the lock pin 42 shown in FIG. 6 by a chain double-dashed line. Therefore, as shown in FIG. 8A, when the lock member 47 is moved toward the cam member 33, the head portion 54 of the lock pin 42 enters the lock space 61 and engages the engagement groove 56. engages with the engaging portion 59 of the locking member 47 . On the other hand, as shown in FIG. 8B, when the lock members 47 are moved away from each other from the position shown in FIG. The head 54 can pass through the pin through hole 57 inside the radial arc surface 62a.

As shown in FIGS. 6A and 7A, when the lock member 47 is moved in the direction of approaching the cam member 33, the engaging portion 59 engages the engaging groove 56 and the head portion 54 is closed. is in the locked position. At this time, the head 54 enters into the locking space 61 . On the other hand, as shown in FIGS. 6(B) and 7(B), when the locking member 47 is moved away from the cam member 33, that is, moved radially outward, the engaging portion 59 is engaged. It is in a release position away from groove 56 .

A spring member 63 made of a compression coil spring is provided in a spring chamber 64 formed in each locking member 47 . A spring force is applied to each locking member 47 by a spring member 63 in a direction to approach the cam member 33 , that is, in a direction in which the engaging portion 59 engages the engaging groove 56 .

The cam member 33 is reciprocally rotated within a range of 90 degrees around the central axis O of rotation. A guide hole 66 into which the guide pin 65 is inserted is formed in the cam member 33 in an arc shape.

As shown in FIG. 6, the cam surface 67, which is the outer peripheral surface of the elliptical cam member 33, has a large diameter surface 67a with a diameter D1 and a short surface 67a at a position shifted by 90 degrees from the diameter D1 in the rotational direction. The outer diameter gradually changes between the large diameter surface 67a and the small diameter surface 67b. The large diameter surface 67a forms the release surface and the small diameter surface 67b forms the locking surface. When the cam member 33 is rotated by the electric motor 31 so that the diameter D2 is in the direction along the radial direction axis R, which is the moving direction of the lock member 47, the small diameter surface 67b constituting the lock surface is shifted to the direction shown in FIG. away from the cam contact surface 68 formed on the inner surface of each locking member 47, as shown in FIG. Thereby, as shown in FIG. 7A, the lock member 47 is brought to the lock position where it is engaged with the engagement groove 56 by the spring force of the spring member 63 . At this time, the guide pin 65 contacts one end face of the guide hole 66 .

Therefore, as shown in FIG. 1, the abutting surface 44 of the tool unit 12 abuts against the mounting surface 29 of the master unit 11, and the heads 54 of the four lock pins 42 are inserted into the pin through holes 57 of the lock member 47. , the tool unit 12 is fastened to the master unit 11 by the four lock pins 42 when the lock member 47 is at the lock position.

On the other hand, as shown in FIG. 6B, the electric motor 31 is rotated so that the diameter D1, which is larger than the diameter D2, is in the direction along the radial direction axis R, which is the movement direction of the lock member 47. When the cam member 33 is rotated in the opposite direction to rotate 90 degrees clockwise from the position shown in FIG. Then, the cam contact surfaces 68 of the lock members 47 are pressed against the spring force to move the lock members 47 away from each other. As a result, the lock member 47 is driven to the release position where the engagement between the engagement groove 56 and the engagement portion 59 is released, as shown in FIG. 7(B). At this time, the guide pin 65 contacts the other end surface of the guide hole 66 .

Therefore, when the lock member 47 is driven to the release position, the fastening of the tool unit 12 to the master unit 11 by the lock pin 42 is released, and the tool unit 12 can be removed from the master unit 11. Furthermore, another tool unit different from the removed tool unit 12 can be attached to the master unit 11 .

When performing operations such as processing and transporting a workpiece using the tool changing device 10 described above, the tool unit 12 is attached to the master unit 11 attached to the tip of the robot arm as a moving device. A plurality of tool units 12 are arranged on a support base (not shown), and a specific tool unit 12 is attached to the master unit 11 in conformity with the operation using the tool changer.

To attach the tool unit 12 to the master unit 11, as shown in FIGS. 6(B) and 7(B), the cam member 33 moves the two lock members 47 away from each other. As a result, the pin through hole 57 is coaxial with the through hole 46 of the support plate 24 so that the head 54 of the lock pin 42 can pass through the pin through hole 57 of the lock member 47 . Under this condition, the master unit 11 is brought closer to the tool unit 12 by the robot arm 13, the head 54 of the lock pin 42 of the tool unit 12 is positioned at the position of the pin through hole 57, and the pin through hole 57 is closed. let it pass.

Further, when the cam member 33 is rotated counterclockwise by 90 degrees by the electric motor 31, the lock member 47 is driven to the lock position by the spring force as shown in FIGS. 6(A) and 7(A). . As a result, the engagement portion 59 of the lock pin 42 of the lock member 47 is engaged with the engagement groove 56 , and the tool unit 12 is fastened to the master unit 11 by the lock pin 42 . Under this condition, the tool unit 12 can be operated by the robot arm 13 to perform a predetermined work. When the electric hand 14 is attached to the tool unit 12 as an operating member, the electric hand 14 grips the work, and the robot arm 13 conveys the work.

When removing the tool unit 12 from the master unit 11, the cam member 33 is moved from the locked position shown in FIGS. 6(A) and 7(A) to the released position shown in FIGS. 6(B) and 7(B). rotate.

In this way, by rotating the cam member 33 by the electric motor 31, the tool unit 12 is fastened to the master unit 11, and by rotating it in the opposite direction to the fastening, the fastening is released. The tool changer 10 can have a simple structure.

The cam surface 67 of the cam member 33 includes a large-diameter surface 67a whose long axis radius is half the radius D1 from the rotation center axis O, and 90 degrees in the rotational direction with respect to the long axis radius of this large-diameter surface 67a. The cam member 33 can drive the two lock members 47 at the same time. However, even with a single lock member 47 without providing two lock members 47, it is possible to switch between a state in which the tool unit 12 is fastened to the master unit 11 by the lock pin 42 and a state in which the fastening is released. In that case, the cam surface 67 can be provided with one large-diameter surface 67a and one small-diameter surface 67b, and the large-diameter surface 67a and the small-diameter surface 67b are shifted 180 degrees in the rotation direction of the cam member 33. can also be formed. Also, although the lock member 47 locks two lock pins 42 , one lock pin 42 may be locked by one lock member 47 .

FIG. 9 is a cross-sectional view showing the same parts as in FIG. 7 in a tool changer according to another embodiment, and in FIG. 8, the head 54 of the locking pin 42 is shown in phantom to show the engaging portion 59 and the pin through hole 57. As shown in FIG.

As shown in FIG. 9, the engaging portion 59 formed on the lock member 47 is provided on the cam member 33 side with respect to the pin through hole 57, unlike the case described above. Therefore, when the two lock members 47 are brought closer to each other, the engaging portion 59 of the lock member 47 is in the released position where it does not contact the head portion 54 of the lock pin 42, as shown in FIG. 9(A). On the other hand, when the two locking members 47 are moved apart from each other, the engaging portion 59 of the locking member 47 comes into contact with the head portion 54 of the locking pin 42 as shown in FIG. 9(B). Become.

The spring member 63 is mounted in the spring chamber 64 in the same manner as described above, with one end surface of the spring member 63 contacting the bottom surface of the spring chamber 64 and the other end surface contacting the end wall surface 53 . Therefore, the spring member 63 applies spring force in a direction to release the engaging portion 59 of the locking member 47 from the engaging groove 56 of the locking pin 42 .

The large-diameter surface 67a of the cam surface 67 of the cam member 33 presses against the cam contact surfaces 68 of the two lock members 47 to form lock surfaces that drive the lock members 47 to the lock position as shown in FIG. Configure. On the other hand, the small diameter surface 67b of the cam surface 67 is separated from the cam contact surfaces 68 of the two lock members 47 and constitutes a release surface that drives the lock members 47 to the release position as shown in FIG. 9(A).

Also in the master unit 11 of the form shown in FIG. 9, a single locking member 47 can be used without providing two locking members 47. Also, although the lock member 47 locks two lock pins 42 , one lock pin 42 may be locked by one lock member 47 .

The cam member 33 is formed by a plate cam, and the cam surface 67 is brought into contact with the cam contact surface 68 of the lock member 47 with the outer peripheral surface as the cam surface 67 . However, the cam member 33 is not limited to a plate cam, and a positive cam can be used. As the positive cam, for example, the lock member 47 may be formed with either a groove or a projection, and the cam member 33 may be provided with a groove or projection that meshes with the groove or projection of the lock member 47 . In that case, the spring member 63 becomes unnecessary.

The present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the spirit of the present invention. For example, although the case where the tool changing device is attached to the robot arm has been described, the tool changing device of the present invention is applicable not only to the robot arm but also to any moving device having a member for moving the tool unit. . In addition, although the electric hand 14 is attached to the tool unit 12 in the embodiment, the work equipment is not limited to the electric hand 14, and the tool unit 12 to which jigs and tools are attached can be used as the master unit. 11 can be installed.

The tool changing device of the present invention can be used to detachably attach the tool unit to the master unit.

Claims

a master unit in which an electric motor is incorporated;
a tool unit provided with an operation device and fitted with a lock pin projecting toward the master unit;
a cam member provided in the master unit and rotationally driven by the shaft of the electric motor;
a lock member provided on the master unit movably in a direction transverse to the rotation center axis of the cam member;
The tool changing device, wherein the lock member moves between a lock position where the lock pin is engaged with the engagement groove of the lock pin and a release position where the lock pin is separated from the engagement groove by the cam member.
A tool changer according to claim 1, wherein
The master unit has a support plate having a mounting surface against which the abutment surface of the tool unit abuts, the cam member is rotatably supported by the support plate, and the lock pin passes through the support plate. A tool changer provided with a through hole for
3. In the tool changer according to claim 1 or 2,
The cam member has a release surface for contacting the cam contact surface of the lock member to drive the lock member to the release position, and a lock surface having a diameter smaller than the radius of the release surface. A tool changer, wherein the lock member is provided with a spring member that engages the lock member with the engagement groove when facing the cam contact surface.
A tool changer according to claim 3, wherein
The cam member has a release surface comprising a major radius cam surface and a locking surface comprising a minor radius cam surface rotationally offset relative to the major radius.
In the tool changer according to any one of claims 1 to 4,
A tool changer, wherein two lock members are provided in the master unit so as to face each other via the cam member.
In the tool changer according to any one of claims 1 to 5,
a guide hole provided in the cam member;
a guide pin attached to the master unit and entering the guide hole;
A tool changer, wherein the guide pin regulates rotation of the cam member.
In the tool changer according to any one of claims 1 to 6,
The tool changing device, wherein the locking member has two engaging portions respectively engaged with the engaging grooves of the two locking pins.