JPS6153198B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a robot having multiple axes.

It is desired that the structure of such a robot be as simple as possible.

The present invention provides a first single-axis drive device 1 having a horizontal axis and a working means 5;
a second single-axis drive device 2 having a vertical axis for vertically moving the second single-axis drive device 2; and a third single-axis drive device 2 for moving the second single-axis drive device 2 along a horizontal axis perpendicular to the horizontal axis of the first single-axis drive device 1. a shaft drive device 3; the first single-shaft drive device 1 comprises: a first elongated moving body 4 having a horizontal axis and having a working means 5 attached to one end; and both sides of the first moving body 4; a pair of first rails 26, 27 that extend horizontally and parallel to each other on one side and guide the first moving body 4; The first threaded rod 17, the first movable body 4, the first rails 26, 27, and the first threaded rod 17 are surrounded, the first rails 26, 27 are fixed, and the first threaded rod 17 is moved around the horizontal axis. a first servo motor 13 having an output shaft 14 connected to an end of a threaded rod 17 opposite to the working means 5 and fixed to the end of the first case 6; and a first nut 24, 25 fixed to the first moving body 4 and screwed onto the first threaded rod 17, having an axis parallel to the first threaded rod 17 within the case 6 and rotating around the axis. The rotary cylinders 31 and 32 are supported, and the cylinder part 44 is fixed to the end of the rotary cylinders 31 and 32 on the side of the working means 5 and has spline irregularities formed on its inner peripheral surface. a first rotary shaft 40 that is inserted into the cylindrical portion 44 , has an unevenness formed on the outer peripheral surface thereof to form a spline by fitting into the unevenness of the cylindrical portion 44 , and has a free end portion 43 connected to the working means 5 ; a first bevel gear 45 that meshes with the first bevel gear and has an axis perpendicular to the first rotating shaft 40; a second bevel gear 46 that is fixed to the first case 26 and that is fixed to the first case 26
The second single-axis drive device 2 includes a second moving body 75 to which the outer wall of the first case is fixed.
and a pair of second rails 73 and 74 that guide both sides of the second moving body 75 and extend parallel and vertically to each other.
and between the second rails 73 and 74 and the second rail 7
The second threaded rod 67 extends parallel to the rails 73, 74, and the second rails 73, 74 are fixed to the second threaded rod 67. a second case 60 that is rotatably supported around the second case 60; a third servo motor 81 that is fixed to the end of the second case 60 and drives the second threaded rod 67 around its axis; and a third servo motor 81 that is fixed to the second moving body 75. a second nut 79 that is screwed onto the second threaded rod 67; A pair of pulleys 92, 93 are freely supported, respectively, and a pair of pulleys 92, 93 are wound around the pulleys 92, 93.
A cable 91 whose both ends are connected to the second movable body 75 and has an endless shape; a double-acting cylinder 94 having a piston 95 connected to the cable 91 and having an axis extending vertically; Compressed air is supplied to the upper piston chamber 97, and this air pressure allows the piston 95 to receive a reaction force due to the weight of the second moving body 75 and the first single-axis drive device 1 fixed to the second moving body 75. such an air pressure source 99, which is connected to said upper piston chamber 97 and whose value is selected to be able to maintain said upper piston chamber 9 at a pressure slightly greater than said air pressure;
7 to the atmosphere, and the lower piston chamber 96 of the double-acting cylinder 94 is released to the atmosphere. A pair of third rails 136 and 137 that guide both ends of the moving body 135 and the third moving body 135 and extend horizontally parallel to each other and perpendicular to the horizontal axis of the first single-axis drive device 1.
and a third threaded rod 129 extending between the third rails 136, 137 and parallel to the third rails 136, 137.
and the third rails 136, 137 and the third threaded rod 129
a main body 120 which surrounds the main body 120, has third rails 136, 137 fixed thereon, and rotatably supports a third threaded rod 129 around its axis;
a fourth servo motor 131 that drives the third screw rod 12 around its axis;
This robot has a plurality of axes, and is characterized in that it includes a third nut 134 that is screwed into the third nut 9.

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a front view thereof, FIG. 3 is a side view thereof, and FIG. 4 is a plan view thereof. This robot basically includes a first single-axis drive device 1, a second single-axis drive device 2, and a third single-axis drive device 3. The moving body 4 provided in the first single-axis drive device 1 is
Move in the left-right direction of the figure, that is, in the x-axis direction. Second
A first single-axis drive device 1 is attached to the single-axis drive device 2, and this second single-axis drive device 2 moves the first single-axis drive device 1 up and down in the vertical direction in FIG. 3, that is, in the y-axis direction. drive The third single-axis drive device 3 includes a second
A single-axis drive device 2 is installed. This third single-axis drive device 3 displaces the second single-axis drive device 2 in the vertical direction of FIG. 4, that is, in the z-axis direction. A working means 5 for performing gripping work is removably attached to the end of the moving body 4. Instead of the working means 5 that performs this gripping work, a working means such as a drill may be installed.

FIG. 5 is a longitudinal sectional view of the first single-axis drive device 1, FIG. 6 is a horizontal sectional view thereof, FIG. 7 is a sectional view taken from the cutting plane line - in FIG. FIG. 8 is a sectional view taken along the section line - in FIG. 6. The first single-axis drive device 1 basically consists of the above-mentioned moving body 4 and a case 6 as a main body. The case 6 consists of four side walls 7, 8, 9, 10 and two end walls 11, 12. A DC servo motor 13 is mounted on the end wall 11. This DC servo motor 13 is equipped with a detector that detects the speed of its output shaft 14. The moving body 4 has a square or rectangular cross section perpendicular to its axis, and has a large section modulus. The movable body 4 is driven to advance and retreat into the case 6 along the longitudinal direction of the movable body 4 by a screw feed mechanism 15.

In the screw feeding mechanism 15, the screw rod 17 has an axis parallel to the longitudinal direction of the moving body 4, and has a bearing 18,
19 to the case 6. This threaded rod 17 is connected to the DC servo motor 13 by a shaft coupling 20.
is connected to the output shaft 14 of. The other end of the threaded rod 17 is connected to an encoder 22 by a shaft coupling 21 . Nuts 24 and 25 fixed to the movable piece 231 are screwed into the threaded rod 17. Such threaded rod 17 and nuts 24, 25 may be ball screws. The moving piece 231 is guided by a pair of rails 26 and 27 extending parallel to the threaded rod 17.

The above-mentioned working means 5 is removably attached to a mounting plate 29 fixed to the end of the cylindrical body 28 of the movable body 4. A pair of rotary cylinders 31 and 32 having axes parallel to the threaded rod 17 are provided within the case 6 to transmit rotational force to the working means 5. This rotating tube 3
1 and 32 are supported by a bearing 34 and a bearing 35 on a support plate 33 on the end wall 11 side. Encoders 38 and 39 are connected to the ends of the rotary cylinders 31 and 32 by shaft couplings 36 and 37.

The vicinity of the other end of the rotary cylinder 31 is shown enlarged in FIG. A rotating shaft 40 is inserted into the rotating tube 31 . This rotating shaft 40 is inserted into an insertion hole 41 formed in the end wall 12 of the case 6 . This rotating shaft 40
The end portion of the mounting plate 29 is supported by a bearing 42 on the mounting plate 29 . This bearing 42 receives the radial force and thrust force of the rotating shaft 40. Free end portion 4 of rotating shaft 40
3 is connected to the working means 5 and rotational force is transmitted thereto.

The rotating shaft 40 is formed with spline irregularities, and a cylindrical portion 44 fixed to the end of the rotating cylinder 31 is inserted through the rotating shaft 40 .

As is clear from FIG. 10, the rotating shaft 40 and the cylindrical portion 44, and therefore the rotating barrel 31, are spline-coupled and are mutually displaceable in the axial direction, but rotate integrally in the circumferential direction. do. Cylinder part 44
A bevel gear 45 is fixed to. This bevel gear 4
5 meshes with a bevel gear 46 having an axis perpendicular to the axis of the rotating shaft 40. A rotating shaft 50 connected to the bevel gear 46 is supported by a radial bearing 48 and a thrust bearing 49. case 47
is attached to the side wall 9 of the case 6 by the bracket 251.
Fixed. The rotating shaft 50 is connected to a DC servo motor 5 fixed to the outside of the side wall 9 via a shaft coupling 51.
2. Bearing 5 provided in case 47
3 and 54 support the cylindrical portion 44. The other rotating barrel 32 has the same configuration as the rotating barrel 32, and a rotating shaft 55 is inserted through the rotating barrel 32, and its end 56 transmits rotational force to the working means 5. The rotary shaft 55 is driven by a DC servo motor 57, similar to the configuration related to the rotary shaft 40.

FIG. 11 is a vertical cross-sectional view of the second single-shaft drive device 2 seen from the front, FIG. 12 is a vertical cross-sectional view of the second single-shaft drive device 2 seen from the side, and FIG. 13 is a vertical cross-sectional view of the second single-shaft drive device 2 seen from the side. FIG. 12 is a horizontal sectional view taken along the cutting plane line - in FIG. 11; The case 60 of the second single-axis drive device 2 is
It consists of four side walls 61, 62, 63, 64 and two end walls 65, 66. Inside this case 60,
A threaded rod 67 extending vertically is supported by bearings 68 and 69. The bearing 68 receives the radial force of the threaded rod 67, and the bearing 69 receives the radial force and thrust force of the threaded rod 67. The bearing 68 is attached to the end wall 65
The bearing 69 is attached to the end wall 66 via a bracket 70. side wall 63,6
4 has a reinforcing material 7 whose cross section perpendicular to the axis is formed in a C-shape.
1 and 72 are fixed to its side walls 63 and 64. This reinforcing body 72 has a pair of rails 73, 7 extending parallel to the axis of the threaded rod 67 on both sides of the threaded rod 67.
4 is fixed. The rails 73 and 74 are the moving body 7
5 legs 76, 77 are guided. A nut 79 that is screwed onto the threaded rod 67 is fixed to the moving body 75. One lower end of the threaded rod 67 is connected to a DC servo motor 81 via a shaft coupling 80 . The other upper end of the threaded rod 67 is connected to an encoder 83 by a shaft coupling 82 . DC servo motor 81
is equipped with a detector for detecting the rotational speed of the threaded rod 67.

The moving body 75 is provided with an auxiliary drive means 90. A movable piece 78 is fixed to the movable body 75, and both ends of a cable 91 such as a wire rope are connected to this movable piece 78, thus forming an endless loop. The cable 91 is wound around pulleys 92 and 93 rotatably supported by the case 60. The pulleys 92 and 93 have axes perpendicular to the axis of the threaded rod 67, and are arranged further above and below the movable range of the moving piece 78, respectively. A piston 95 of a double-acting cylinder 94 is fixed to the cable 91 .

FIG. 14 is a simplified diagram of the auxiliary drive means 90. Of the two piston chambers 96 and 97 partitioned by the piston 95 of the double-acting cylinder 94, one piston chamber 96 is open to the atmosphere, and the other piston 97 is connected to air pressure through a pipe 98. source 99. A relief valve 100 is connected to this conduit 98. Mobile body 75
A mounting seat 102 attached to the side wall 7 of the first single-axis drive device 1 is fixed.

The air pressure of the air pressure source 99 is selected to a value that can receive the reaction force due to the weight of the moving piece 78, the first single-axis drive device 1, and the like. As a result, when the threaded rod 67 and the first single-shaft drive device 1 are at rest, no downward force is applied to the nut 79. The pressure of the relief valve 100 is chosen to be slightly greater than the air pressure of the air pressure source 99. Threaded rod 67 for raising the first single-axis drive 1
is driven by the servo motor 81, the nut 79 is displaced downward in FIGS. 11, 12, and 14. As a result, the pressure in the piston chamber 97 increases, and the relief valve 100 becomes open. Therefore, even if the capacity of the servo motor 81 is small, it is possible to easily rotate the threaded rod 67 and raise the first single-axis drive device 1. piston 95
Atmospheric air is introduced into the piston chamber 96 when the piston moves downward.

In order to lower the first single-axis drive device 1, the threaded rod 67 is driven by the servo motor 81 to lower the nut 79. At this time, the piston 95 rises, whereby the air in the piston chamber 97 is discharged from the relief valve 100, and the atmosphere is sucked into the piston chamber 96. The air pressure in the piston chamber 97 supports the weight of the first single-axis drive device 1, etc., so even if the first single-axis drive device 1 descends rapidly, the small capacity of the servo motor 81 can provide accurate Vertical positioning can be performed.

A long hole 111 formed in the side wall 62 for allowing movement of the movable body 75 has covers 112 and 113 that are extendable and retractable on both sides of the reciprocating direction of the movable body 75.
is placed. The covers 112 and 113 are covered by a cover body 213 fixed to the side wall 62.

FIG. 15 is a horizontal cross-sectional view of the third single-axis drive device 3, FIG. 16 is a vertical cross-sectional view thereof, and FIG. 17 is a cross-sectional view taken along the section line - in FIG. 15. The main body 120 has a side wall 12 made of angle iron.
1, 122, end walls 123, 124, and a reinforcing body 125 made of channel steel. Reinforcement body 125,1
A threaded rod 129 extending in the Z-axis direction is rotatably supported by bearings 127 and 128 attached to the bearings 26 . Bearing 127 supports radial and thrust forces, and bearing 128 supports radial forces. One end of the threaded rod 129 is connected to a DC servo motor 131 via a shaft coupling 130. The other end of the threaded rod 129 is connected to the encoder 13 via a shaft coupling 132.
3. Servo motor 131 includes a speed detector that detects the rotational speed of threaded rod 129. A nut 134 screwed onto the threaded rod 129 is fixed to a movable body 135. A rail 1 extending parallel to the axis of the threaded rod 129 is provided above the side walls 121 and 122.
36,137 are fixed. Legs 138 and 139 of the movable body 135 are supported by the rails 136. An end wall 66 of the second single-axis drive device 2 is fixed to the upper part of the moving body 135 via a mounting piece 140. An electrical connector 141 is connected to the moving body 135, and the electrical connector 141 is connected to the first uniaxial drive device 1 and the second uniaxial drive device 2 via flexible wires. Electrical signals are transmitted and received to and from the electrical connector 141 via a flexible wire 142 . Expandable covers 143 and 144 for dustproofing are provided on both sides of the movable body 135 in the reciprocating direction, and these covers 143 and 144 are connected to the cover body 145 fixed to the side walls 121 and 122.
covered by.

FIG. 18 is a block diagram showing a control device for the robot shown in FIGS. 1 to 17. The first single-axis drive device 1, the second single-axis drive device 2, and the third single-axis drive device 3 are connected to a common processing circuit 151 configured by an analog computer or the like via a connection terminal 150. Common processing circuit 151
A teaching device 152 is connected through a connection terminal 150 to the teaching device 152 . The common processing circuit 151 includes
Via the connection terminal 153 an individual processing circuit 154 for the first uniaxial drive 1 , an individual processing circuit 155 for the second uniaxial drive 2 and an individual processing circuit 156 for the third uniaxial drive 3 is connected.
The working procedure of the first single-axis driving device 1 is performed by operating the teaching device 152, and the working procedure of the first single-shaft driving device 1 is performed by the individual processing circuit 1.
54. The reproduction work operation of the first single-axis drive device 1 is performed according to the contents stored in the individual processing circuit 154, and a signal is derived via the common processing circuit 151. As a result, the first single-shaft drive device 1 performs the regeneration work operation. The second single-axis drive device 2 and the third single-axis drive device 3 similarly perform cooperative operations with the individual processing circuits 155 and 156 via the common processing circuit 151. Sequential related control of the operations of the first single-axis drive device 1 to the third single-axis drive device 3 is performed by a common processing circuit 1
51.

The first single-axis drive device 1 to the third single-axis drive device 3 are
They can be individually attached to and detached from the connection terminals 150. The individual processing circuits 154 to 156 also connect to the connection terminal 153.
It can be selectively attached and detached. According to such a configuration, the first single-axis drive device 1 to the third single-axis drive device 3
When one or more of the single-axis drive units 1 to 3 are used, the corresponding individual processing circuits 154 to 156 are attached to the respective terminals 153 and used, so the unused first to third unit Individual processing circuits 154 to 1 corresponding to the shaft drive device 3
56 is not attached, thus simplifying the construction and eliminating waste.

FIG. 19 is a plan view of a part of a factory in which the first single-axis drive device 1 is installed. A product 162 forged by the press device 160 is placed on a conveyor 164 and conveyed by a dispensing device 163. The product 162 carried by the conveyor 164 is sucked up by a vacuum suction device 165. This vacuum suction device 165 is attached to the movable body 4 of the first single-axis drive device 1 . conveyor 16
4, another conveyor 166 is arranged in parallel. The first single-axis drive device 1 includes a conveyor 164,
It is fixed to a support 167 that spans above 166. The vacuum suction device 165 is fixed to the movable body 4 of the first single-axis drive device 1 . Vacuum suction device 165
The product 162 that has been attracted and lifted by the conveyor 166 is moved by the action of the first single-axis drive device 1
and is conveyed on the conveyor 166 by the extrusion device 168. 19th like this
In the factory shown in the figure, the individual processing circuit 154 shown in FIG. 18 is used in connection with the first single-axis drive 1, and the remaining second and third single-axis drives 2 and Processing circuits 155, 15
6 is unnecessary and will not be used. The control device is therefore simplified.

FIG. 20 is a simplified front view of a part of a factory using the first single-axis drive device 1 and the second single-axis drive device 2. FIG. A product 171 conveyed by the conveyor 170 is placed on a conveyor 172. This conveyor 172 is tilted as shown by a virtual line 174 by the driving force of the cylinder 173. Along with this, the product 171 is transferred to the conveyor 172.
tilted up. This tilted product 171 is suspended from a hanger conveyor 175 that runs at intervals in a direction perpendicular to the plane of the paper of FIG. 20 using the first single-axis drive device 1 and the second single-axis drive device 2.
The hanger conveyor 175 conveys the products in a tilted state as shown by the reference numeral 174.
A hook 178 attached to the movable body 4 of the first single-axis drive device 1 for hanging on the hanger 176 of the
performs the operation shown in FIG. The hook 178 moved by the single-axis drive device follows movement paths a, b, c, and d, and moves by the second single-shaft drive device 2 to follow movement paths e, f, and g. Hook 17
8 moves forward in the direction of path a,
The hook 178 is inserted into a hook hole formed in the product 171. The hook 178 then moves upward along path e, and then moves forward along path b. The hanger 176 is then hooked into the hook hole of the product 171 by lowering the hook 178 along the path f. Then, by retracting the hook 178 as shown in path c,
The hooking state between the hooking tool 178 and the hooking hole of the product 171 is released. Then, the hook 178 follows path c, then descends as shown in path g, and retreats again as shown in path d to return to its original position. In such a factory, the third single-axis drive device 3 and the individual processing circuit 156 are omitted in the control device shown in FIG.

As another embodiment of the invention, the single-axis drive may have angular displacement functions such as swivel, oscillation, wrist swing for the working means 5, and the single-axis drive for performing such angular displacements. A robot can be constructed by combining devices.

As described above, according to the present invention, the following effects are achieved.

(a) The first single-axis drive device 1 is raised and lowered by the second single-axis drive device 2, and the third single-axis drive device 3
Since the second single-axis drive device 2 is moved by the second single-axis drive device 2, the working means 5 can be made to follow the predetermined shortest necessary path, and after simplifying the work procedure to be performed, the robot according to the present invention This allows the robot to perform work using the minimum number of axes, maximizing the performance of each axis of the robot.

(b) In the first single-shaft drive device 1, the spline-coupled first rotating shaft 40 is connected to the working means 5, and the desired work can be achieved with a simple structure.

(c) The cylindrical portion 44 through which the first rotating shaft 40 is inserted is
and is driven by the second servo motor 52 via the second bevel gears 45 and 46, so the second
A mounting location for the servo motor 52 can be easily secured, and this also simplifies the structure.

(d) In the second single-axis drive device 2, the reaction force due to the weight of the second moving body 75 and the first single-axis drive device 1 can be received by the air pressure of the air pressure source 99, so that the third servo motor 81 can be made small and accurate positioning can be performed.

(e) Furthermore, since air pressure is used, a buffering effect is achieved, and generation of large impact force when the first single-shaft drive device 1 is lowered can be avoided.

(f) Furthermore, the configuration of the third single-axis drive device 3 is also simplified. This facilitates implementation of the invention.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a front view of the robot, FIG. 3 is a side view of the robot, FIG. 4 is a plan view of the robot, and FIG. A vertical cross-sectional view of the single-axis drive device 1, FIG.
A horizontal cross-sectional view of the single-axis drive device 1, FIG. 7 is a cross-sectional view taken from the cutting plane line - of FIG. 6, FIG. 8 is a cross-sectional view taken from the cutting plane line - of FIG. 6, and FIG. 9 is a cross-sectional view taken from the cutting plane line - of FIG. An enlarged cross-sectional view showing the configuration for driving the rotating shaft 40 related to the rotating cylinder 31, FIG. 10 is a cross-sectional view taken from the cutting plane line - in FIG. 9, and FIG. 11 shows the second single-shaft drive device 2 Figure 12 is a cross-sectional view of the
13 is a sectional view taken from the side of the single-axis drive device 2, FIG. 13 is a sectional view taken from the cutting plane line - in FIG. 12, and FIG. 14 is a simplified diagram for explaining the operation of the second single-axis drive device 2. FIG. 15 is a horizontal cross-sectional view of the third single-axis drive device 3, FIG. 16 is a vertical cross-sectional view of the third single-shaft drive device 3, and FIG. 18 is a block diagram showing the control device for the robot shown in FIGS. 1 to 17, and FIG. 19 is a plan view of a part of the factory including the first single-axis drive device 1. 20 is a simplified front view of a factory including the first single-axis drive device 1 and the second single-axis drive device 2, and FIG. 21 is a diagram showing the working path of the hook 178 in the factory shown in FIG. 20. It is. 1... First single-axis drive device, 2... Second single-axis drive device, 3... Third single-axis drive device, 4, 75, 13
5... Moving object, 5... Working means, 13, 52, 8
1,131...DC servo motor, 17,31,
32,67,129...Threaded rod, 22,38,3
9,83,133...Encoder, 91...Cable, 92,93...Pulley, 94...Double acting cylinder, 99...Pneumatic pressure source, 100...Relief valve,
150, 153...Connection terminal, 151...Common processing circuit, 152...Teaching device, 154-
156...Individual processing circuit.

Claims (1)

[Scope of Claims] 1. A first single-axis drive device 1 that is equipped with a working means 5 and has a horizontal axis; and a second single-axis drive device 2 that has a vertical axis that drives the first single-axis drive device 1 up and down. and the second single-axis drive device 2 is connected to the first single-axis drive device 1.
a third uniaxial drive 3 moving along a horizontal axis perpendicular to the horizontal axis of the first uniaxial drive 1, the first uniaxial drive 1 having a horizontal axis and having a working means 5 attached to one end thereof. a long first moving body 4; a pair of first rails 26, 27 extending horizontally and parallel to each other on both sides of the first moving body 4 and guiding the first moving body 4; 27, a first threaded rod 17 extending horizontally between the first rails 26, 27 and parallel to the first rails 26, 27; 26 and 27 are fixed, and a first case 6 supporting the first threaded rod 17 around the horizontal axis; and an output shaft 14 connected to the end of the threaded rod 17 opposite to the working means 5; a first servo motor 13 fixed to an end of the first case 6; a first nut 24, 25 fixed to the first moving body 4 and screwed into the first threaded rod 17; The rotary cylinders 31 and 32 have an axis parallel to the threaded rod 17 and are rotatably supported around the axis. A cylindrical portion 44 is formed on the circumferential surface, and a concavity and convexity is formed on the outer circumferential surface of the cylindrical portion 44 and is inserted into the cylindrical portion 44 and fits into the concave and convex portions of the cylindrical portion 44 to form a spline. a first bevel gear 45 fixed to the cylindrical portion 44; a second bevel gear 46 meshing with the first bevel gear and having an axis perpendicular to the first rotating shaft 40; Fixed to the first case 26, the second bevel gear 46
The second single-axis drive device 2 includes a second moving body 75 to which the outer wall of the first case is fixed.
and a pair of second rails 73 and 74 that guide both sides of the second moving body 75 and extend parallel and vertically to each other.
and between the second rails 73 and 74 and the second rail 7
The second threaded rod 67 extends parallel to the rails 73, 74, and the second rails 73, 74 are fixed to the second threaded rod 67. a second case 60 that is rotatably supported around the second case 60; a third servo motor 81 that is fixed to the end of the second case 60 and drives the second threaded rod 67 around its axis; and a third servo motor 81 that is fixed to the second moving body 75. a second nut 79 that is screwed onto the second threaded rod 67; A pair of pulleys 92, 93 are freely supported, respectively, and a pair of pulleys 92, 93 are wound around the pulleys 92, 93.
A cable 91 whose both ends are connected to the second movable body 75 and has an endless shape; a double-acting cylinder 94 having a piston 95 connected to the cable 91 and having an axis extending vertically; Compressed air is supplied to the upper piston chamber 97, and this air pressure allows the piston 95 to receive a reaction force due to the weight of the second moving body 75 and the first single-axis drive device 1 fixed to the second moving body 75. such an air pressure source 99, which is connected to said upper piston chamber 97 and whose value is selected to be able to maintain said upper piston chamber 9 at a pressure slightly greater than said air pressure;
7 to the atmosphere, and the lower piston chamber 96 of the double-acting cylinder 94 is released to the atmosphere. A pair of third rails 136 and 137 that guide both ends of the moving body 135 and the third moving body 135 and extend horizontally parallel to each other and perpendicular to the horizontal axis of the first single-axis drive device 1.
and a third threaded rod 129 extending between the third rails 136, 137 and parallel to the third rails 136, 137.
and the third rails 136, 137 and the third threaded rod 129
a main body 120 which surrounds the main body 120, has third rails 136, 137 fixed thereon, and rotatably supports a third threaded rod 129 around its axis;
a fourth servo motor 131 that drives the third screw rod 12 around its axis;
a third nut 134 screwed into the third nut 134;