JPH065105Y2 - Robot wrist device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a wrist device having at least two axes of freedom at the tip of a robot arm.

(Prior Art) Conventionally, as a wrist device of this type, as disclosed in Japanese Utility Model Laid-Open No. 61-9295, as shown in FIG. 5, a wrist body a constituted by a tip end portion of a robot arm serves as an axis line of the robot arm. A swing case b swingable around a Y axis orthogonal to the X axis is pivotally supported, and a tool holder c rotatable around a Z axis orthogonal to the Y axis is pivotally supported on the swing case b. These rocking cases b
It is known that the tool holder c and the tool holder c are driven by separate motors (not shown) mounted on the robot arm.

In this device, the drive shaft d of the motor for the rocking case and the drive shaft e of the motor for the tool holder are arranged on the X axis so as to be double inside and outside, and these drive shafts d and e are input to the wrist main body a. The pair of first and second bevel gear mechanisms f and g serving as gear shafts are housed so that the output gear shafts f ₁ and g _{1 of the both} bevel gear mechanisms are arranged to face each other on one side and the other side on the Y axis, The output gear shaft f ₁ of the first bevel gear mechanism f is formed on the outer surface of the wrist body a on the one side in the Y-axis direction.
A first reduction gear h connected to the first reduction gear h
And a third bevel gear mechanism i in which the output gear shaft i ₁ is arranged on the Z axis, and an input gear of the third bevel gear mechanism i. The transmission mechanism j that connects the output gear shaft g ₁ of the second bevel gear mechanism g to the shaft i ₂ is housed, and the output gear shaft of the third bevel gear mechanism i is provided on the outer surface of the swing case b in the Z-axis direction. i ₁
A second speed reducer k connected to the second speed reducer k
The tool holder c is rotated via the.

(Problems to be Solved by the Invention) In the above-mentioned one, since the speed reducers h and k are arranged immediately in front of the rocking case b and the tool holder c, respectively, the rocking case b
And bevel gear mechanism f to the operation accuracy of the tool holder c,
The effect of backlash of g and i can be reduced,
In order to further improve the operation accuracy, it is desirable to eliminate backlash.

Further, in order to improve maintainability, it is desired that the wrist main body a can be separated from the robot arm, and that each gear shaft of each bevel gear mechanism can be easily attached and detached. An object of the present invention is to improve the above-mentioned wrist device of the prior art so as to satisfy the above demands.

(Means for Solving the Problem) In order to achieve the above object, in the present invention, in the conventional wrist device, the output gear shaft of the first and second bevel gear mechanisms and the input gear shaft and output of the third bevel gear mechanism are provided. The gear shafts are respectively supported by respective bearing members, and these bearing members are attached to corresponding attachment points of the wrist body and the rocking case via shims, respectively, and further, the first and second bevel gear mechanisms. Of the input gear shaft is separable from the drive shafts of the both motors, and a bearing member that coaxially supports the both input gear shafts is attached to the attachment position of the wrist body in the X-axis direction through a shim, In addition, a mounting base for the robot arm is formed integrally with the bearing member.

(Operation) Since each gear shaft of each bevel gear mechanism is mounted on the wrist body or rocking case by pivotally supporting the gear shaft on the bearing member, as compared with those directly supporting the gear shaft on the wrist body or rocking case, The gear shaft can be easily attached / detached, and the wrist can be easily attached / detached to / from the robot arm at the attachment base formed on the bearing member for the input gear shaft of the first and second bevel gear mechanisms, thereby improving the maintainability of the wrist.

Further, since each bearing member is attached to the wrist body or the swing case through the shim, the backlash of each bevel gear mechanism can be easily removed by adjusting the shim.

(Example) Referring to FIG. 1, (1) is a guide rail (2a) on a base (2)
It shows a traveling platform that is moved back and forth along, and is equipped with a robot arm (4) that can be vertically swung via a swivel platform (3) that can swivel around a vertical axis on the platform (1), A wrist device A having three degrees of freedom was attached to the tip of the robot arm (4) to construct an industrial robot having a six-axis structure as a whole.

As shown in FIGS. 2 and 3, the wrist device A includes a wrist body (5) having a tubular portion (5a) in the X-axis direction, which is the axis of the robot arm (4), and a wrist body (5). A swinging case (6) having a substantially U-shape in plan view, which is swingably supported around a Y axis orthogonal to the X axis at the tip, and the tip of the swinging case (6) is orthogonal to the Y axis. A tool holder (7) rotatably supported around the Z-axis is provided, and a gear box (8) that extends to both sides is attached to the rear end of the robot arm (4), and the gear box (8) is attached to the gear box (8). , 4th
As shown in the figure, the motor for the wrist body (9) (hereinafter referred to as the X-axis motor), the motor for the rocking case (10) (hereinafter referred to as the Y-axis motor), and the motor for the tool holder (11) (Hereinafter Z
A shaft motor) will be mounted in the robot arm (4), and the speed reducer (1) in the gear box (8) by the X-axis motor (9) will be installed.
2) and a gear, an X-axis drive shaft (9a), and a Y-axis motor (10), which is driven via a gear.
0a) and a Z-axis drive shaft (11a) which is driven by a Z-axis motor (11) via a gear, are arranged on the X-axis in triple layers, and the wrist body (5) is provided with a Y-axis drive shaft. A first bevel gear mechanism (13) having an input gear shaft (13a) that is spline-fitted to the outer periphery of the end of (10a), and an input gear shaft (14a that is spline-fitted to the inner periphery of the end of the Z-axis drive shaft (11a). Second bevel gear mechanism (1)
4) and stored.

The both input gear shafts (13a) (14a) are the cylindrical parts of the wrist body (5).
And input gear shaft of the second bevel gear mechanism to the first Bearing member (18 ₁₎ in the interpolated tubular in (5a) (14) and (14a) to the outside is pivotally supported on the inner and outer double, said An outer end portion of the first bearing member (18 ₁ ) is screwed to the outer end surface of the tubular portion (5a) through a shim (19), and further, the X-shaped portion is attached to the outer end of the first bearing member (18 ₁ ). When the mounting base (20) bolted to the shaft drive shaft (9a) is integrally formed and the base (20a) is connected to the shaft (9a), the both input gear shafts (13a) (14a) are Y-shaped. The shafts and the Z-axis drive shafts (9a) and (10a) are connected to each other.

Also, the output gear shaft (13b) of the both bevel gear mechanisms (13) (14)
Second and third bearing members (18 ₂ ) and (18 ₃ ) that respectively support (14b).
The provided second Bearing member (18 ₂₎ to the opening of the Y-axis direction one side of the distal end of the wrist body (5), and third Bearing member (18 ₃₎ of the wrist body
The output gears (13b) and (14b) are attached to the openings on the other side in the Y-axis direction at the tip of (5) via shims (19) so as to face one side and the other side on the Y-axis. The first bearing member.
The position adjustment of the both input gear shafts (13a) (14a) in the X-axis direction by the shim (19) of (18 ₁ ) and the second and third bearing members (18 ₂ ) (18 ₃ )
The first and second bevel gear mechanisms (13) are adjusted by adjusting the positions of the output gear shafts (13b) and (14b) in the Y-axis direction by using the shim (19).
Removed the backlash in (14).

A first speed reducer (17 ₁ ) is attached to the outer surface of the tip of the wrist body (5) on one side in the Y-axis direction via the second bearing member (18 ₂ ). (17 ₁₎ to the first bevel gear mechanism which is pivotally supported by the second Bearing member (18 ₂₎ (14) of the output gear shaft (13b)
Was connected. First reduction gear (17 _1), as the second reduction gear to be described later and (17 ₂₎ is constituted by a known cyclo speed reducer in Japanese Unexamined Utility Model Publication No. 63-131386 or the like, a shaft (17a) case has become the output from any of (17b) in Todaseru so, in this embodiment fixed first reduction gear (17 ₁₎ of the shaft (17a) to a second Bearing member (18 _2), wherein first reduction gear tail one side of the pivot case (6) (17 ₁₎ cylindrical portion for receiving the tubular portion to form a (6a) (6a) to the first speed reducer (17) of the case ( A lid body (6b) for applying an outer peripheral flange (17c) formed in 17b) to the tubular portion (6a)
Fastened together by, while fitting the tail end other side of the swing casing (6) in the third Bearing member (18 ₃₎ opening the outer periphery of the Y-axis direction end for mounting a wrist body (5) Shaft support and thus the rocking case
The first bevel gear mechanism (13) and the first reduction gear (17 ₁₎ and the Y-axis of the swing through was as given in (6).

The swing case (6) has a first gear chamber (6c) at the tip thereof.
And the second gear chamber (6d) over the entire length on the other side in the Y-axis direction.
Are formed, the third bevel gear mechanism (15) is arranged in the first gear chamber (6c), its input gear shaft (15a) is parallel to the Y axis, and its output gear shaft (15b) is aligned with the Z axis. So as to connect the input gear shaft (15a) and the output gear shaft (14b) of the second bevel gear mechanism (14) to the second gear chamber (6d). Transmission mechanism consisting of two gears fixed to 15a) (16)
Stored. In the figure, (6e) shows a lid that covers the second gear chamber (6d).

The input gear shaft (15a) and the output gear shaft (15b) of the third bevel gear mechanism (15) are respectively provided at the opening on the other side in the Y axis direction and the opening in the Z axis direction of the first gear chamber (6c). The fourth and fifth bearing members (18 ₄ ) (18 ₅ ) mounted via the shims (19) respectively support the respective bearings, and the shims (19) of the fourth bearing members (18 ₄ ) are used for input. Gear shaft
And position adjustment of the Y-axis direction (15a), by performing the position adjustment of the Z-axis direction of the output gear shaft (15b) by a shim (19) of the fifth Bearing member (18 _5), the third bevel gear mechanism Removed the backlash of (15).

Further, the second reduction gear (17 ₂ ) is attached to the outer side surface of the swinging case (6) in the Z-axis direction via the fifth bearing member (18 ₅ ), and the third reduction gear (17 ₂ ) is attached thereto.
The output gear shaft (15b) of the bevel gear mechanism (15) was connected.

Second reduction gear (17 _2), the flange of the case (17b) (17
In c) it is fastened to the fifth Bearing member (18 ₅₎ with the pivot case (6), wherein the connecting the tool holder (7) to the shaft (17a), the said tool holder (7) Te thus Second bevel gear mechanism (14), transmission mechanism (16), and third bevel gear mechanism (15)
If was so given the Z-axis of rotation via the second reduction gear (17 _2).

Said wrist body (5) is first journalled member attached thereto (18 ₁₎
Is attached to the X-axis drive shaft (9a) as described above at the mounting base (20), and the wrist main body (5) is rotated about the X-axis to allow the Y-axis of the swing case (6) to be rotated. By swinging around and turning the tool holder (7) around the Z-axis, 3
Axis motion control is performed.

(Effect of the Invention) As is apparent from the above description, according to the present invention, the backlash of each bevel gear mechanism can be removed to improve the operation accuracy of the rocking case and the tool holder, and each gear of each bevel gear mechanism can be improved. The shaft can be easily attached and detached, and maintainability is improved.

[Brief description of drawings]

FIG. 1 is a side view of an example of a robot equipped with the device of the present invention,
2 is a cutaway plan view of the wrist device, FIG. 3 is a side view with a part thereof cut away, and FIG. 4 is a cutaway plan view of the robot arm,
FIG. 5 is a cross-sectional view of a conventional example. (4) …… Robot arm, (5) …… Wrist body (6) …… Swing case, (7) …… Tool holder (10) …… Swing case motor, (11) …… Tool holder Motor (10a) (11a) …… Drive shaft, (13) …… First bevel gear mechanism (14) …… Second bevel gear mechanism (15) …… Third bevel gear mechanism (13a) (14b) (15a) …… Input gear shaft (13b) (14b) (15b) …… Output gear shaft (16) …… Transmission mechanism, (17 ₁ ) …… First reduction gear (17 ₂ ) …… Second reduction gear (18 ₁ ) 〜 (18 ₅ ) …… Bearing member (19) …… Shims, (20) …… Mounting base

Claims (1)

[Scope of utility model registration request] 1. A wrist body attached to the tip of a robot arm, and a swing case swingably supported on the wrist body around a Y axis orthogonal to the X axis which is the axis of the robot arm.
The rocking case is provided with a tool holder rotatably supported around a Z axis orthogonal to the Y axis, and the rocking case and the tool holder are driven by respective motors mounted on a robot arm. And a first bevel gear mechanism having an input gear shaft connected to a drive shaft of a motor for a rocking case, and an input connected to a drive shaft of a motor for a tool holder. Second with gear shaft
A bevel gear mechanism, in which both input gear shafts are inside and outside on the X-axis.
And the output gear shafts of both bevel gear mechanisms are
A first speed reducer for connecting the output gear shaft of the first bevel gear mechanism is attached to the outer surface of the wrist body on the one side in the Y-axis direction so as to be opposed to the one side and the other side on the shaft. , The first
The rocking case is rocked via a speed reducer,
Further, the swing case accommodates a third bevel gear mechanism in which an output gear shaft is arranged on the Z-axis, and a transmission mechanism that connects the input gear shaft of the third bevel gear mechanism to the output gear shaft of the second bevel gear mechanism. At the same time, a second reduction gear that connects the output gear shaft of the third bevel gear mechanism is attached to the outer surface of the swing case in the Z-axis direction, and the tool holder is rotated through the second reduction gear. In the above, the first
The output gear shaft of the second bevel gear mechanism and the input gear shaft and the output gear shaft of the third bevel gear mechanism are rotatably supported by different bearing members, and these bearing members are respectively provided on the wrist body and the swing case. The respective input gear shafts are mounted on the corresponding mounting positions via shims respectively, and further, the input gear shafts of the first and second bevel gear mechanisms are separable from the drive shafts of the both motors, and the both input gear shafts are coaxially supported. A wrist device for a robot, characterized in that a bearing member is attached to a mounting portion of the wrist body in the X-axis direction via a shim, and a mounting base for a robot arm is integrally formed on the bearing member.