JPH08141949A - Wrist shaft for rectangular robot - Google Patents

Abstract

PURPOSE: To improve rigidity and minimize a wrist shaft without causing any inconvenience in a wiring as a motor is not turned and moved even if the wrist shaft is turned and moved. CONSTITUTION: A wrist fitting shaft which forms one shaft in movement shafts and comprises a hollow frame is composed of a wrist shaft 51 attached to a tip of the wrist fitting shaft and motors 43 and 44 installed in the wrist fitting shaft apart from the wrist shaft 51 and a power transmission means 55 installed between a rotation shaft of the wrist shaft 51 and rotation shafts of the motors 43 and 44.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a wrist axis of an orthogonal robot. The present invention relates to a so-called wrist axis that is installed at the tip of the moving axis of an orthogonal robot that moves according to each moving axis such as the X axis, Y axis, and Z axis.

[0002]

2. Description of the Related Art Conventionally, as an orthogonal robot, FIG.
3, an orthogonal robot as shown in FIG. 14 is known. That is, 101 is the X axis, 102 is the Y axis, and 103 is the Z axis.
It is an axis and constitutes each moving axis. The final axis Z-axis 103
A wrist 104 axis is attached. The wrist shaft 104 is rotated in two orthogonal directions. That is, the motors 105 and 106 installed orthogonally rotate in the orthogonal directions. In the orthogonal robot shown in FIG. 13, the motor 106 is attached to the tip of the shaft driven by the motor 105, and as a result, the shaft driven by the motor 106 is rotated in two orthogonal directions. In the Cartesian robot shown in FIG. 14, the wrist axes are rotated in two orthogonal directions via gears by the motors 105 and 106 installed side by side. Also in this conventional example, the motor 105 and the motor 10
6 moves with the movement of the wrist axis.

[0003]

However, in the conventional wrist shaft, the motor 1 is rotated by the rotation and movement of the wrist shaft.
05, since the motor 106 also moves, there is a problem that when the wrist shaft rotates 180 ° or more, the wiring of the motor 105 and the motor 106 is caught.

[0004]

Means for Solving the Problems The present invention provides a wrist mounting shaft which constitutes one of the moving shafts and which is composed of a hollow frame,
It consists of a wrist shaft attached to the tip of the wrist attachment shaft, a motor installed on the wrist attachment shaft apart from the wrist shaft, and power transmission means installed between the rotation shaft of the wrist shaft and the rotation shaft of the motor. The present invention relates to a wrist axis of a Cartesian robot.

[0005]

When the motor is driven, the driving force is transmitted to the wrist shaft via the power transmission means, and the wrist shaft is rotated. Since the motor is fixed to the wrist mounting shaft, it does not move even if the wrist shaft rotates.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of guides and guide rails used in the present invention will be described below with reference to the drawings. Reference numeral 11 is a guide. The guide 11 is formed of a substantially rectangular parallelepiped as a whole as shown in FIG. 1 which is an assembly drawing.
Bearings 14 are provided on the upper surface and upper side surfaces of the guide 11. 12 is a guide rail. Guide rail 1
As shown in FIG. 1 and FIG. 2 showing an end view of the embodiment, reference numeral 2 is a rod-shaped rectangular parallelepiped having a length substantially equal to that of the guide 11, and a driving body locking portion is provided on one surface in the longitudinal direction thereof. , The rack 13 is formed. The guide rail 12 is fixed to the guide 11 with the rack 13 forming surface facing outward as shown in FIG. 2, and constitutes a part of the guide 11. Reference numeral 15 denotes a transported object fixing plate which is a transported object fixing member. As shown in FIGS. 1 and 2, the plate 15 is provided with a flat mounting surface 16 on its upper surface, has a U-shaped cross section, and is fitted into the guide 11 with its inner surface facing downward.

Reference numeral 21 is a table, which is fixed on the plate 15 and constitutes a part of the plate 15. Table 2
An electric motor 22 is fixed to the upper surface of 1. A drive wheel 23 composed of a pinion gear is fixed to the tip of the electric motor 22, and the drive wheel 23 meshes with the rack 13.

Next, the operation of the guide rail used in this embodiment will be described. When the electric motor 22 is driven,
The drive wheel 23 reciprocates along the rack 13 formed on the guide rail 12 forming the outer peripheral surface of the guide 11. The transported object fixing plate 15 moves as the drive wheels 23 move. Reference numerals 24, 25, 26, 27, 28 and 29 are mounting parts. FIG. 3 is a side view of an embodiment in which the end surface of the table 21 is L-shaped and the rack 13 forming surface faces the lower surface. In this embodiment, it becomes easy to install the electric motor on the side surface.

FIGS. 4 and 5 are end views of an embodiment in which the guide rail 12 is not provided and the rack 13 is directly provided on the guide 11. That is, even if the rack is provided directly on the guide 11,
It may be provided on the guide rail 12. In this embodiment, since the guide rail 12 can be omitted, it is possible to further improve the processing accuracy. Then, the drive wheel 23 moves directly according to the rack 13 provided on the guide rail 12.

FIG. 6 is a perspective view of an embodiment of an industrial robot in which the linear conveying device shown in FIGS. 1 to 4 is assembled in the three XYZ directions. That is, 31 is an X-axis linear transport device, 32 is a Y-axis linear transport device, 33.
Is a Z-axis linear transport device. As shown in FIGS. 1, 2, 3, 4, 5 and the like, these linear transport devices 31, 32, 33 respectively have a guide 11, a rack 13,
Plate 15, table 21, electric motor 22, drive wheel 23
Etc. The end of the guide 11 of the Y-axis linear transport device 32 is fixed to the table 21 of the X-axis linear transport device 31 via mounting parts 24 and 25. Similarly, on the table 21 of the Y-axis linear direction transport device 32, Z
The axial linear transport device 32 is fixed via the mounting parts 24, 25. At the tip of the Z-axis linear direction transfer device 33, a welding spot gun and other work unit mounting portion 34 for fixing an actuator are provided. An operation unit 35 controls the drive of each electric motor 22, and supplies an electric current to the working unit attachment unit 34.

Next, the operation of the guide rail used in this embodiment will be described. The amount of movement from the operation unit 35 to the predetermined position of the working unit attachment unit 34 is analyzed as the amount of movement in the XYZ three-axis directions, and each motor 2 is moved according to the amount of movement in each axial direction.
Supply current to 2. Then, the electric motor 22 is driven to rotate each drive wheel 23. Then, the drive wheel 23 moves to the guide 11
The guide rail 12 or the guide 1 that constitutes the outer peripheral surface
It moves along the rack 13 directly provided on the No. 1. Therefore, the transported object fixing plate 15 moves as the drive wheels 23 move. Each linear transport device 31, 32,
Each of the movements of 33 causes the working unit mounting portion 34 to move to a desired three-dimensional position. Then, an actuator such as a welding spot gun attached to the working portion attachment portion 34 is operated. Further, the working portion mounting portion 34
Other shafts may be installed in sequence.

Therefore, in the guide rail used in the embodiment of the present invention, the guide has a flat and substantially rectangular parallelepiped shape, and the plate has a substantially U-shaped cross section and is fitted to the outer peripheral surface of the guide at the inner peripheral surface. Therefore, it is stable and has rigidity. Further, since the guide rail can be omitted, the processing accuracy can be further improved and the processing is easy. Furthermore, it is not necessary to provide a frame separately from the guide,
The guide also serves as the frame. Therefore, it is not necessary to obtain parallel accuracy between the frame and the guide, and since the electric motor itself moves, the stop position can be easily controlled.

Next, an embodiment of the present invention will be described with reference to FIGS. 41 is an orthogonal robot. The orthogonal robot 41 includes an X-axis linear transport device 31 forming the X-axis and a Y-axis linear transport device 3 forming the Y-axis.
2 and the Z-axis linear direction conveying devices 33 constituting the Z-axis are made orthogonal to each other, and each axis is a guide 1 shown in FIGS.
1 is assembled as shown in FIGS.
Although the wrist attaching shaft is composed of the Y-axis linear transport device 32 which constitutes the Y-axis in this embodiment, it may be composed of the X-axis, the Z-axis or the like. Y-axis linear transport device 3, which is a wrist mounting shaft
2, the hollow frame 42 having a rectangular shape and the guide 11 are fixed to each other as shown in FIG. FIG.
The plate 15 is attached to the X-axis as shown in FIG. 43 is a 4th axis drive motor, 44 is a 5th axis drive motor. Fourth axis drive motor 43, fifth axis drive motor 4
Both 4 are arranged side by side at one end of the Y-axis linear transport device 32 which is a wrist mounting shaft. 51 is a wrist axis and is the fourth
The shaft drive motor 43 and the fifth shaft drive motor 44 are attached to the tip of the hollow frame 42 at the end opposite to the attachment ends. The wrist shaft 51 is a sheath-shaped wrist shaft main body 52, and a fourth shaft reducer 53 attached to the lower end of the tip of the wrist shaft main body 52,
Fifth axis reducer 5 attached to the tip of fourth axis reducer 53
4 and. The sheath-shaped wrist shaft main body 52 is fixed by inserting the tip of the hollow frame 42. 55 is a power transmission means. The power transmission means 55 is a belt in this embodiment, and the fourth shaft drive motor 43 is provided in the hollow frame 42.
Is installed between the drive shaft and the shaft of the fourth shaft reducer 53 to transmit the driving force. Similarly, the power transmission means 55 is installed in the hollow frame 42 between the drive shaft of the fifth shaft drive motor 44 and the shaft of the fifth shaft reducer 54 to transmit the driving force. Although the power transmission means 55 is a belt in this embodiment, it may be driven by a chain or a shaft. A working unit 56 is attached to the tip of the fifth shaft reducer 54.

Next, the operation of the embodiment will be described. When the fourth axis drive motor 43 is driven, the driving force is transmitted through the power transmission means 55 to the fourth axis reducer 5 constituting the wrist axis 51.
3, the wrist shaft 51 is rotated. When the fifth axis drive motor 44 is driven, the driving force is transmitted to the fifth axis reducer 54 constituting the wrist shaft 51 via the power transmission means 55,
The wrist shaft 51 is rotated.

Since the fifth axis drive motor 44 and the fourth axis drive motor 43 are fixed to the Y-axis linear transport device 32 which is a wrist mounting axis, they do not move even if the wrist axis rotates. The working unit 56 moved to the working position works on the work piece.

[0016]

[Effects of the Invention] Therefore, in the present invention, since the motor does not move rotationally even if the wrist shaft rotates or moves, there is no inconvenience in wiring, rigidity is improved, and size reduction is achieved.

[Brief description of drawings]

FIG. 1 is a component diagram of a guide rail used in an embodiment of the present invention in an assembled state.

FIG. 2 is an end view of a guide rail used in an embodiment of the present invention.

FIG. 3 is an end view of a guide rail used in another embodiment of the present invention.

FIG. 4 is an end view of a guide rail used in another embodiment of the present invention.

FIG. 5 is an end view of a guide rail used in another embodiment of the present invention.

FIG. 6 is a perspective view of a guide rail used in an embodiment of the present invention in a state of being used in a three-axis robot.

FIG. 7 is a front view of an embodiment of the present invention.

FIG. 8 is a partially enlarged central sectional view of the embodiment of the present invention.

FIG. 9 is a plan view of an embodiment of the present invention.

FIG. 10 is a side view showing a state where the guide rail according to the embodiment of the present invention is attached to the guide rail.

FIG. 11 is a partial perspective view of an embodiment of the present invention.

FIG. 12 is a schematic perspective view of an embodiment of the present invention.

FIG. 13 is a perspective view of a conventional example.

FIG. 14 is a perspective view of a conventional example.

[Explanation of symbols]

 11 guides, 12 guide rails 13 racks 15 plates 22 electric motors 23 drive wheels 32 wrist mounting shafts (Y-axis linear transfer device) 43 fourth axis drive motors 44 fifth axis drive motors 51 wrist shafts 55 power transmission means

Claims (1)

[Claims] 1. A wrist mounting shaft that constitutes one of the moving shafts and is composed of a hollow frame, a wrist shaft that is mounted at the tip of the wrist mounting shaft, and a motor that is installed on the wrist mounting shaft apart from the wrist shaft. A wrist axis of a Cartesian robot comprising a power transmission means installed between a rotation axis of a wrist axis and a rotation axis of a motor.