Carrier device

Abstract

To achieve high speed in a device while preventing the entire device from being enlarged.SOLUTION: A carrier device 1 includes a fixed base 10 which has a large gear 14, a swivel body 20 which is supported on the fixed base 10 through a bearing 16, two or more servomotors 30, a carrier arm 50, and two or more speed reducers 40. A speed reducer 40 comprises a housing 41 united with the swivel body 20, a planetary carrier 42 supported rotatably inside the housing 41, an internal gear 43 provided inside the housing 41, a sun gear 44 connecting an output shaft 32 of the servomotor 30, a plurality of planetary gears 45 arranged around the sun gear 44 and supported rotatably by the planetary carrier 42, and an output gear 46 rotating integrally with the planetary carrier 42. The planetary gear 45 meshes with the sun gear 44 and also meshes with the internal gear 43. The output gear 46 has a smaller diameter than the large gear 14, and meshes with the large gear 14 outside the large gear 14.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a transfer device that transfers a workpiece using a transfer arm. [Background technology]

[0002] Conventionally, in a transport device that rotates a transport arm, an eccentric oscillating reducer is often used in the drive mechanism for rotating the transport arm (for example, Patent Document 1). Since such an eccentric oscillating reducer has small backlash, it has the advantage of providing excellent positional accuracy during transport operation when used in a transport device.

[0003] Also, a reducer using a planetary gear in a drive mechanism for a joint of a robot or the like is known (for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-212839 A [Patent Document 2] JP 2018-202545 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when it is assumed that an industrial robot equipped with an eccentric oscillating type reducer such as that in Patent Document 1 is used as, for example, a transport device for transporting a workpiece to be processed by a press from a stacker loaded with the workpiece to a press, a transport device for transporting a workpiece processed by a press from the press to a stocker, or a transport device for transporting a workpiece from one press to another among a plurality of presses, it is necessary to perform a reciprocating (oscillating) operation of the transport arm at a higher speed within a limited area (space) in order to improve production efficiency. If the rotation speed of the transport arm is increased for this purpose, the inside of the reducer will generate heat and the components will expand, resulting in a problem of limiting the speed increase.

[0006] In addition, the reducer of Patent Document 2 suppresses heat generation even when the reciprocating motion of the transport arm is accelerated. However, in order to increase the output torque of the motor in order to realize high-speed rotation using an inexpensive and lightweight motor, it is necessary to connect the gears in multiple stages to increase the reduction ratio. In this case, connecting the gears in multiple stages increases the distance from the rotation axis of the transport arm to the center of gravity of the motor. In other words, the moment of inertia of the rotating part of the transport device itself increases. This increase in the moment of inertia limits the increase in the acceleration and deceleration of the transport arm that continuously reciprocates within a limited area, and ultimately prevents the realization of continuous high-speed transport.

[0007] Therefore, the present invention provides a transport device that can easily ensure a large reduction ratio of the reducer and can achieve high speed movement of the transport arm that repeats swinging motion. [Means for solving the problem]

[0008] The present invention has been made to solve at least some of the above-mentioned problems, and can be realized in the following aspects or application examples.

[0009] [1] One aspect of the conveying device according to the present invention is A fixed base having a large gear which is an external gear; a rotating body supported on the fixed base via a bearing; Two or more servo motors that rotate the rotating body relative to the fixed base; A transport arm configured to be capable of transporting a workpiece by rotating together with the rotating body; Two or more reducers fixed to the rotating body and connected to the two or more servo motors, respectively; Including, the speed reducer includes a housing integral with the revolving body, a planetary carrier rotatably supported inside the housing, an internal gear provided inside the housing, a sun gear connected to an output shaft of the servo motor, a plurality of planetary gears disposed around the sun gear and rotatably supported by the planetary carrier, and an output gear rotating integrally with the planetary carrier; the planetary gear meshes with the sun gear and meshes with the internal gear; The output gear has a smaller diameter than the large gear and meshes with the large gear on the outside thereof.

[0010] According to one aspect of the transport device, it is possible to increase the rotation speed of the rotating body and the transport arm while suppressing heat generation by using planetary gears instead of an eccentric oscillating reducer that is prone to heat generation as in Patent Document 1. Also, according to one aspect of the transport device, it is possible to easily ensure a high reduction ratio by arranging two or more reducers using planetary gears around a large gear that is an external gear.

[0011] [2] In one embodiment of the conveying device, The fixed base has an annular end portion protruding from the fixed base, The annular end portion has an outer circumferential surface on which the annular gear is fixed, and an inner circumferential surface on which an outer ring of the bearing is fixed, The pivot body has an annular fixing portion disposed along an inner side of the annular end portion, The annular fixing portion has an inner ring of the bearing fixed to an inner circumferential surface of the annular fixing portion, The fixed base and the rotating body have an opening formed inside the annular fixed portion along a rotation axis of the rotating body, Wires may be configured to extend from the fixed base to the servo motor through the opening.

[0012] According to one aspect of the conveying device, an opening can be provided on the inside of the large gear, making it possible to use the opening for wiring. Also, according to one aspect of the conveying device, a large opening can be provided to match the large gear, making it possible to employ a large servo motor that requires a thick power line.

[0013] [3] In one embodiment of the conveying device, The workpiece may be a metal plate for press working or a product after press working.

[0014] According to one aspect of the conveying device, even when conveying a metal workpiece, the conveying speed of the workpiece can be increased. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a perspective view of a transport device according to the embodiment. [Diagram 2] 2 is a cross-sectional view taken along line AA in FIG. 1. [Diagram 3] 3 is a cross-sectional view of FIG. 2 taken along line B-B. [Figure 4] 3 is a cross-sectional view taken along CC in FIG. 2. [Diagram 5] 13 is an enlarged view showing a part of a vertical cross section of a transport device according to a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below are not intended to unduly limit the content of the present invention described in the claims. In addition, not all of the configurations described below are necessarily essential components of the present invention.

[0017] 1. Overview of the transport device 1 is a perspective view of a conveying device 1 according to this embodiment. The conveying device 1 includes a fixed base 10, a swivel body 20 rotatable relative to the fixed base 10, two or more servo motors 30, a conveying arm 50 that swivels together with the swivel body 20, and two or more reducers 40 connected to the two or more servo motors 30, respectively. The conveying device 1 may include a control device 6 that controls the operation of the conveying device 1.

[0018] The fixed base 10 is fixed on a machine base 11. In this embodiment, an example in which there are two servo motors 30 is shown, but the number is not limited to this and may be three or more. The two servo motors 30 can rotate the swivel body 20 relative to the fixed base 10.

[0019] The transport arm 50 is configured to be able to rotate together with the swivel body 20 to transport the workpiece 2. The transport arm 50 is fixed to the swivel body 20. The transport device 1 can be a so-called multi-joint robot, for example, a four-axis robot. The transport arm 50 includes a plurality of long members, for example, a first arm 51, a second arm 52, and a long member 53. The transport arm 50 can include a first drive mechanism 55, a second drive mechanism 56, and a third drive mechanism 58, each of which includes a servo motor. The transport arm 50 can further include a first lever set 57a and a second lever set 57b, which are formed of a link mechanism. One end of the first arm 51 is rotatably connected to the swivel body 20, and the first drive mechanism 55 rotates the first arm 51 up and down to raise and lower the other end. The second arm 52 is rotatably connected to the other end of the first arm 51. The first lever set 57a is connected to one end of the second arm 52 and is operated by the second drive mechanism 56. The second drive mechanism 56 operates the first lever set 57a to move the other end of the second arm 52 back and forth relative to the swivel body 20. The third drive mechanism 58 is fixed to the other end of the second arm 52 via the second lever set 57b, and moves up and down while maintaining a horizontal state even when the first arm 51 moves up and down. The long member 53 has one end rotatably connected to the third drive mechanism 58 and has a plurality of suction members 54 that hold the workpiece 2 at the other end (the free end of the transport arm 50). The long member 53 rotates the workpiece 2 horizontally relative to the other end of the second arm 52 by driving the third drive mechanism 58. The transport arm 50 can appropriately adopt a transport arm structure of a known articulated robot, and the suction member 54 is not limited to a suction mechanism as long as it can hold the workpiece 2, and may be, for example, a gripping mechanism.

[0020] The conveying device 1 is disposed adjacent to the press machine 3, for example. The conveying device 1 may also be disposed between a plurality of press machines 3, for example, and configured to convey a work from an upstream press machine to a downstream press machine. The work 2 may be a metal plate for press processing or a product after press processing. The conveying device 1 drives the servo motor 30 to horizontally rotate the swivel body 20 and the conveying arm 50 about the first rotation axis 24, and conveys the work 2 onto the press machine 3. This conveying operation, for example, involves rotating the first arm 51 by the first driving mechanism 55 to raise and lower the work 2, rotating the second arm 52 by the second driving mechanism 56 to move the work 2 forward and backward, and rotating the long member 53 by the third driving mechanism 58 to horizontally rotate the work 2, thereby conveying the work 2 to an appropriate position. Press-processed products tend to be heavy, and improved productivity is required in press processing. According to the conveying device 1, even when conveying a metal work 2 to be used in press processing, it is possible to increase the conveying speed of the work 2. In this embodiment, an example in which the workpiece 2 is transported to the press machine 3 will be described, but the workpiece 2 may be disposed adjacent to a device other than the press machine 3. For example, in the case of a machine tool, the workpiece 2 may be a processed product or material after cutting, and in the case of an injection molding machine, the workpiece 2 may be a plastic product or an insert.

[0021] The control device 6 is electrically connected to each operating unit of the transport device 1. The control device 6 may receive signals from a sensor (not shown) of the transport device 1. The control device 6 may also be a part of the control device of the press machine 3. The control device 6 includes, for example, an operation unit, a calculation unit, a storage unit, a display unit, and an output unit. The control device 6 includes, for example, a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), a storage medium such as a ROM (Read Only Memory), a RAM (Random Access Memory), or a HDD (Hard Disk Drive), a communication interface for high-speed data communication, and a user interface such as a display, a touch panel, or a keyboard. A part or all of the control device 6 may be provided on a cloud via the Internet.

[0022] The transport operation of the transport device 1 can be set in advance using the operation unit. The display unit can display the set contents and execution status of the transport operation. The calculation unit executes each process for executing the set transport operation. Then, the transport device 1 can operate according to the transport operation stored in the memory unit by a command signal from the output unit of the control device 6.

[0023] 2.Description of the reduction mechanism The speed reducing mechanism of the conveying device 1 will be described in detail with reference to Fig. 2 to Fig. 4. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1, Fig. 3 is a cross-sectional view taken along line BB in Fig. 2, and Fig. 4 is a cross-sectional view taken along line CC in Fig. 2.

[0024] The transport device 1 includes a fixed base 10 having a large gear 14 that is an external gear, and a swivel body 20 supported on the fixed base 10 via a bearing 16. The transport device 1 further includes two or more servo motors 30 fixed to the swivel body 20 via a reducer 40, a transport arm 50 having a fixed end fixed to the swivel body 20, and two or more reducers 40 fixed to the swivel body 20.

[0025] The fixed base 10 is disposed on a machine base 11 and rotatably supports the swivel body 20 and the transport arm 50. The fixed base 10 has, for example, an annular end portion 12 that protrudes from the fixed base 10. The fixed base 10 can be a hollow cylinder, and the annular end portion 12 is formed at the upper end of the cylinder. An annular gear 14 is fixed to the outer circumferential surface of the annular end portion 12, and an outer ring 16b of a bearing 16 is fixed to the inner circumferential surface of the annular end portion 12.

[0026] The bearing 16 is a rolling bearing including an outer ring 16b fixed to the fixed base 10, an inner ring 16a fixed to the swivel body 20, and balls or rollers between the outer ring 16b and the inner ring 16a. The bearing 16 is disposed, for example, in one horizontal plane. The bearing 16 is, for example, a cross roller bearing.

[0027] The rotating body 20 is an integral member with the transport arm 50 that covers the annular end 12 so as to straddle the annular end 12 from the inside to the outside. The base end of the transport arm 50 is fixed to the upper surface of the rotating body 20. The rotating body 20 rotates about a first rotation axis 24 relative to the fixed base 10 by driving the servo motor 30, so that the transport arm 50 and the workpiece 2 can be rotated about the first rotation axis 24. The first rotation axis 24 is a virtual line that is the rotation center of the rotating body 20 and is shown by a dashed line in the figure. The rotating body 20 has an annular fixed portion 26 that is arranged along the inside of the annular end 12. The inner ring 16a of the bearing 16 is fixed to the inner peripheral surface of the annular fixed portion 26. An annular seal member S is provided between the annular fixed portion 26 and the fixed base 10 below the portion where the inner ring 16a is fixed.

[0028] The fixed base 10 and the swivel body 20 have a first fixing portion 26 and a second fixing portion 27 of the swivel body 20. An opening 22 is formed along the first rotation axis 24. The conveying device 1 may be configured so that the wiring 36 extends from the fixed base 10 to the servo motor 30 through the opening 22. According to the conveying device 1, the opening 22 can be provided inside the large gear 14, so that wiring can be performed using the opening 22. Also, according to the conveying device 1, a large opening 22 can be provided in accordance with the large gear 14, so that a large servo motor 30 that requires a thick power line can be adopted. The wiring 36 may include a power line to the first drive mechanism 55 and the like other than the servo motor 30, and may include a signal line to a sensor (not shown). Also, the wiring 36 may extend below the fixed base 10 and be connected to the control device 6.

[0029] The reducer 40 includes a housing 41, a planetary carrier 42, an internal gear 43, a sun gear 44, a plurality of planetary gears 45, and an output gear 46.

[0030] The housing 41 is integral with the revolving body 20. The housing 41 is substantially cylindrical with an opening at the top and bottom, and is placed and fixed so that its lower end extends into the inside of the revolving body 20, and the servo motor 30 is placed and fixed at its upper end.

[0031] The planetary carrier 42 is rotatably supported inside the housing 41. The planetary carrier 42 is substantially cylindrical and is attached to the housing 41 via bearings arranged at two locations, one above the other, on the outer periphery of the planetary carrier 42. An output gear 46 is fixed integrally to the lower end of the planetary carrier 42. The rotation axis of the output shaft 32 is the second rotation axis 34. Therefore, when the planetary carrier 42 rotates about the second rotation axis 34, the output gear 46 rotates about the second rotation axis 34. The second rotation axis 34 is, for example, a virtual line parallel to the first rotation axis 24 extending in the vertical direction, and is shown by a dashed line in the figure. An annular seal member S is provided between the inner circumferential surface at the lower end of the housing 41 (below the bearings) and the outer circumferential surface of the planetary carrier 42. The seal member S is an oil seal, and the seal member S seals the lubricating oil in the narrow housing 41, thereby minimizing the amount of oil used in the planetary reduction mechanism.

[0032] The internal gear 43 is provided inside the housing 41. The internal gear 43 is formed integrally with the inner circumferential surface of the cylindrical housing 41 so as to surround the planetary carrier 42. The internal gear 43 is formed in a plane perpendicular to the second rotation axis 34, here, in a single horizontal plane.

[0033] The sun gear 44 is connected to the output shaft 32 of the servo motor 30. The sun gear 44 is provided on the outer periphery of the lower end of a rod connected to the output shaft 32. The rod extends from the output shaft 32 to the inside of the planetary carrier 42 along the second rotation axis 34. The sun gear 44 is an external gear, and transmits the rotation of the output shaft 32 to the reducer 40.

[0034] The planetary gears 45 are arranged around the sun gear 44 and rotatably supported by the planetary carrier 42. In this embodiment, the number of planetary gears 45 is three, but the number is not limited to three, and may be four or more. The upper and lower rotation shafts 45a of the planetary gears 45 are rotatably supported by the planetary carrier 42. The upper and lower rotation shafts 45a may be fixed to the planetary carrier 42 so that the planetary gears 45 are rotatable relative to the rotation shafts 45a. The rotation shafts 45a are parallel to the second rotation axis 34. The rotation shafts 45a are arranged around the second rotation axis 34, and are arranged so that a part of the planetary gears 45 protrudes outward from the outer circumferential surface of the planetary carrier 42. Each planetary gear 45 meshes with the sun gear 44 on the center side of the planetary carrier 42, and meshes with the internal gear 43 at a position protruding from the planetary carrier 42.

[0035] The output gear 46 rotates integrally with the planetary carrier 42. The output gear 46 has a smaller diameter than the large gear 14 and meshes with the large gear 14 on the outside of the large gear 14. The output gear 46 is an external gear with an outer diameter larger than the outer diameter of the planetary carrier 42. The outside and bottom of the output gear 46 are covered by the revolving body 20.

[0036] 3, in the conveying device 1, by driving the servo motor 30, the output shaft 32 and the sun gear 44 rotate, and the three planetary gears 45 meshing with the sun gear 44 rotate, and each planetary gear 45 meshes with the internal gear 43, so that each planetary gear 45 rolls along the internal gear 43 and rotates the planetary carrier 42 relative to the housing 41. Then, as shown in FIG. 4, when the planetary carrier 42 rotates, the output gear 46 rotates, so that the output gear 46 rotates around the large gear 14 while rolling, and the swivel body 20 supporting the planetary carrier 42 rotates about the first rotation axis 24 relative to the fixed base 10.

[0037] According to the transport device 1, by using the planetary gear 45, heat generation in the reducer 40 can be suppressed even if the rotation speed of the rotating body 20 and the transport arm 50 is increased by the servo motor 30. Also, according to the transport device 1, by arranging two or more reducers 40 around the fixed base 10 having the large gear 14 of the external gear, it is possible to suppress an increase in the size of the entire device while ensuring a high reduction ratio. And, according to the transport device 1, it is possible to respond to the increased speed required for the transport operation of the work 2 to the press machine 3.

[0038] According to the conveying device 1, backlash is larger than in the reduction mechanism of Patent Document 1, so malfunctions due to heat generation are less likely to occur even when the speed is increased. Also, according to the conveying device 1, a higher reduction ratio can be obtained by using the large gear 14 and the output gear 46 compared to Patent Document 2, which uses a planetary carrier as the output shaft, so that with the same motor output, it is easier to increase the rotational angular acceleration of the swivel body 20 and to increase the conveying speed.

[0039] In this embodiment, the center lines of rotation of all gears used in the reducer 40 are parallel to the first rotation axis 24 of the rotating body 20, but this is not limited to this and a non-parallel configuration may be used by using a combination of known gears.

[0040] Furthermore, the control device 6 may perform position control on two or more servo motors 30 so as to cancel out the backlash. By being able to cancel out the backlash, it is possible to achieve high stopping position accuracy at the transfer position of the workpiece 2 even at high speed. To be more specific, although backlash exists between the large gear 14 and the two output gears 46, the backlash during acceleration can be cancelled out by controlling one output gear 46 to generate a large torque and the other output gear 46 to generate a slight counter torque during acceleration, and the backlash can be cancelled out by controlling the opposite during deceleration.

[0041] As a modified example, the reducers 40a and 40b may be connected in multiple stages on the second rotation axis 34 as shown in FIG. 5. FIG. 5 is an enlarged view of a portion of a vertical section (a section corresponding to the AA section in FIG. 2) of the transport device 1a according to the modified example. The basic configuration is the same as that of the transport device 1, so a duplicated description will be omitted. The transport device 1a is configured such that a reducer 40a is added between the sun gear 44 and the reducer 40b, as compared with the transport device 1. The two reducers 40a and 40b are provided in a housing 41. The reducer 40a on the servo motor 30 side has a plurality of planetary gears 45 arranged around a sun gear 44 formed on the output shaft 32 of the servo motor 30, and the planetary gears 45 are rotatably supported by the planetary carrier 42. Each planetary gear 45 meshes with the sun gear 44 on the center side of the planetary carrier 42, and meshes with the internal gear 43 at a position protruding from the planetary carrier 42. The output shaft 47 protrudes from the lower surface of the planetary carrier 42 and rotates integrally with the planetary carrier 42. The output shaft 47 has approximately the same diameter as the output shaft 32, and has a sun gear 44a formed on its outer circumferential surface. The basic configuration of the reducers 40a and 40b is the same as that of the reducer 40 in the embodiment.

[0042] The planetary gears 45 of the reducer 40b on the rotating body 20 side are meshed with the sun gear 44a. Therefore, the conveying device 1a outputs The shaft 32 and sun gear 44 rotate, causing the planetary gears 45 of the reducer 40a to rotate, and each planetary gear 45 rolls along the internal gear 43 to rotate the planetary carrier 42 relative to the housing 41. When the planetary carrier 42 rotates, the output shaft 47 rotates, and the output gear 46 of the reducer 40b rotates as in the above embodiment, so that the output gear 46 rotates around the large gear 14 while rolling, and the swivel body 20 supporting the planetary carrier 42 rotates about the first rotation axis 24 relative to the fixed base 10.

[0043] In this way, the reduction ratio can be increased by connecting the multiple reducers 40a, 40b in multiple stages. Therefore, even if each servo motor 30 is an inexpensive and lightweight servo motor and the output torque is reduced, the output torque can be increased by the multiple reducers 40a, 40b, so that the high-speed rotation of the transport arm 50 can be realized. Moreover, since the multiple reducers 40a, 40b are stacked along the second rotation axis 34 (in a direction perpendicular to the rotation plane of the transport arm 50), an increase in the distance between the first rotation axis 24, which is the rotation axis of the transport arm 50, and the center of gravity position of the servo motor 30 is suppressed. Therefore, an increase in the moment of inertia of the rotating body 20 including the reducer 40 is also suppressed, and the acceleration and deceleration of the transport arm 50 can be increased. As a result, the continuous high-speed reciprocating motion of the transport arm 50 in a limited area (space) such as between presses can be realized while suppressing costs.

[0044] The present invention is not limited to the above-described embodiments, and various modifications are possible, including configurations that are substantially the same as those described in the embodiments (configurations with the same functions, methods, and results, or configurations with the same purpose and effect). The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments, or configurations that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments. [Explanation of symbols]

[0045] Reference Signs List 1, 1a...conveyor device, 2...workpiece, 3...press machine, 6...control device, 10...fixed base, 11...machine base, 12...annular end portion, 14...gear, 16...bearing, 16a...inner ring, 16b...outer ring, 20...swivel body, 22...opening, 24...first rotation axis, 26...annular fixed portion, 30...servo motor, 32...output shaft, 34...second rotation axis, 40...reduction gear, 41...housing, 42...planet Carrier, 43... internal gear, 44, 44a... sun gear, 45... planetary gear, 45a... rotating shaft, 46... output gear, 47... output shaft, 50... transfer arm, 51... first arm, 52... second arm, 53... long member, 54 suction member, 55... first drive mechanism, 56... second drive mechanism, 57a... first lever set, 57b... second lever set, 58... third drive mechanism, S... sealing member

Claims

1. A fixed base having a large gear which is an external gear; a rotating body supported on the fixed base via a bearing; Two or more servo motors that rotate the rotating body relative to the fixed base; A transport arm configured to be capable of transporting a workpiece by rotating together with the rotating body; two or more reducers fixed to the rotating body and connected to the two or more servo motors, respectively; Including, the speed reducer includes a housing integral with the revolving body, a planetary carrier rotatably supported inside the housing, an internal gear provided inside the housing, a sun gear connected to an output shaft of the servo motor, a plurality of planetary gears disposed around the sun gear and rotatably supported by the planetary carrier, and an output gear rotating integrally with the planetary carrier; the planetary gear meshes with the sun gear and meshes with the internal gear; A conveying device, wherein the output gear has a smaller diameter than the large gear and meshes with the large gear on the outside of the large gear.

2. 2. The conveying device according to claim 1, The fixed base has an annular end portion protruding from the fixed base, The annular end portion has an outer circumferential surface on which the annular gear is fixed, and an inner circumferential surface on which an outer ring of the bearing is fixed, The pivot body has an annular fixing portion disposed along an inner side of the annular end portion, The annular fixing portion has an inner ring of the bearing fixed to an inner circumferential surface of the annular fixing portion, The fixed base and the rotating body have an opening formed inside the annular fixed portion along a rotation axis of the rotating body, A conveying device, wherein wiring extends from the fixed base to the servo motor so as to pass through the opening.

3. 3. The conveying device according to claim 1, A conveying device, wherein the workpiece is a metal plate for press working or a product after press working.

Images