Transport robots and robot systems

Abstract

To downsize an arm.SOLUTION: A transfer robot comprises a plurality of hands, a plurality of hand driving motors, and one arm. The plurality of hands can hold a transfer object and rotate respectively about one pivot. The plurality of hand driving motors are arranged side by side in such a manner that motor shafts to which the plurality of hands respectively are connected become concentric with respect to the pivot, and as a result, the plurality of hand driving motors directly drive the plurality of hands respectively. One arm incorporates the plurality of hand driving motors.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The disclosed embodiments relate to a transport robot and a robot system. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known a transport robot such as a horizontal articulated robot that transports an object by moving a hand that holds the object.

[0003] Also, in order to reduce the size of the arm of the transport robot, a transport robot that employs an arm-integrated built-in motor has been proposed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-11303 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned conventional technology, the motor and the belt that transmits the driving force of the motor to the hand are built into the arm that supports the hand, and there is room for improvement from the perspective of reducing the size of the arm.

[0006] An object of one aspect of the embodiment is to provide a transport robot and a robot system that can reduce the size of an arm. [Means for solving the problem]

[0007] A transport robot according to one aspect of the embodiment includes a plurality of hands, a plurality of hand drive motors, and one arm. The plurality of hands are capable of holding a transported object and each rotates about a single rotation axis. The plurality of hand drive motors are arranged in a line in a direction along the rotation axis such that motor shafts to which the plurality of hands are respectively connected are concentric with the rotation axis, and directly drive each of the plurality of hands. The single arm incorporates the plurality of hand drive motors. The one arm has a plurality of subframes that can be disassembled along the motor shaft on the side of the plurality of hands. The plurality of subframes each incorporate one of the plurality of hand drive motors, and each has an outer surface that constitutes the outer shape of the one arm on the side of the plurality of hands.

[0008] A robot system according to one aspect of the embodiment includes the above-described transfer robot and a control device. The control device controls the operation of the transfer robot. Effect of the Invention

[0009] According to one aspect of the embodiment, it is possible to provide a transport robot and a robot system that can reduce the size of the arm. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing an overview of a transfer robot. [Diagram 2] FIG. 2 is a perspective view of the transfer robot. [Diagram 3] FIG. 3 is a schematic side view of the first arm, the second arm, and the hand. [Figure 4A] FIG. 4A is a schematic side view of a combination of multiple hand drive motors. [Figure 4B] FIG. 4B is a schematic top view of a combination of multiple hand drive motors. [Figure 5A] FIG. 5A is a schematic side view showing a subframe incorporating a motor. [Figure 5B] FIG. 5B is a schematic side view showing the arm after assembly. [Figure 6] FIG. 6 is a schematic perspective view showing a subframe that does not incorporate a motor. [Figure 7]FIG. 7 is an exploded perspective view of the first motor unit. [Figure 8] FIG. 8 is an exploded perspective view of the second motor unit. [Figure 9] FIG. 9 is a schematic side cross-sectional view of the second arm after assembly. [Figure 10] FIG. 10 is a block diagram of the robot system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A transfer robot and a robot system according to the present invention will be described in detail below with reference to the accompanying drawings. Note that the present invention is not limited to the following embodiments.

[0012] In addition, in the following embodiments, expressions such as "parallel," "vertical," "symmetric," "circular," "semicircular," and "same" may be used, but these conditions do not need to be strictly satisfied. In other words, each of the above expressions allows for deviations in manufacturing accuracy, installation accuracy, processing accuracy, detection accuracy, and the like.

[0013] First, an overview of a transfer robot 10 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing an overview of the transfer robot 10. Fig. 1 shows a perspective view of the transfer robot 10 seen obliquely from above, and also shows a see-through side view of a second arm 12 (see S1 in Fig. 1).

[0014] For ease of explanation, Fig. 1 shows a three-dimensional Cartesian coordinate system with the Z axis, whose positive direction is vertically upward, the X axis, which is along the extension direction of the arm supporting the hand and whose positive direction is the tip side supporting the hand, and the Y axis, which is perpendicular to the X axis and Z axis. This Cartesian coordinate system may also be shown in other drawings used in the following explanation. Note that "orthogonal" means "perpendicular" to each other and "intersects".

[0015] 1, the transport robot 10 includes a main body 15 that is placed on a floor surface or the like, and a lifting unit 16 that moves up and down relative to the main body 15. The lifting unit 16 lifts and lowers a first arm 11 and a second arm 12 that are horizontally linked arms. In addition, a plurality of hands 13 are provided on the tip side of the second arm 12. Specifically, the second arm 12, which is an arm that supports the plurality of hands 13, supports the two hands 13 on the upper surface of the tip side.

[0016] Each of the multiple hands 13 can hold a transported object such as a semiconductor substrate, and each rotates coaxially around the motor shaft AH. In other words, each of the multiple hands 13 rotates on a single rotation axis. Here, to distinguish between the multiple hands 13, capital letters A, B are added to the end of the reference numerals of the hands 13 in order from the hand 13 closest to the second arm 12.

[0017] Although two hands 13 are shown in Fig. 1, there may be three or more hands 13. Furthermore, although two arms (first arm 11 and second arm 12) are shown as horizontal link type arms in Fig. 1, there may be one horizontal link type arm, or there may be three or more horizontal link type arms.

[0018] As shown in S1 in Fig. 1, the second arm 12 incorporates two hand drive motors M that directly drive the two hands 13, respectively, in a position aligned along the motor shaft AH with the motor shaft AH being concentric. In other words, the two hand drive motors M are aligned along the rotation axis of the hand 13, with the motor shafts AH to which the hands 13 are respectively connected being concentric with the rotation axis of the hand 13. Furthermore, each hand drive motor M directly drives the connected hand 13. Note that when multiple hand drive motors M are to be distinguished from one another, numbers are added to the end of the reference numerals, such as M1 and M2.

[0019] In this way, the hand drive motor M is a so-called direct drive motor, and directly drives each hand 13. By incorporating multiple hand drive motors M in the arm in a position where they are concentrically aligned along the motor shaft AH, the space required to accommodate the motors can be reduced. Furthermore, by using a direct drive motor for the hand drive motor M, it is possible to omit a drive belt. As a result, it is possible to reduce the size of the arm.

[0020] As shown in S1 of Fig. 1, each hand drive motor M includes an encoder ME and a hollow shaft MS. Each hand drive motor M is a so-called hollow motor that has a hollow section penetrating along the motor shaft AH. The encoder ME is provided on one side surface (one end surface) in the direction along the motor shaft AH.

[0021] The hollow shaft MS is connected to the rotor of the hand drive motor M, extends along the motor shaft AH, and rotates about the motor shaft AH. The hollow portion of the hand drive motor M communicates with the hollow portion of the hollow shaft MS, and the encoder ME is provided at a position avoiding the hollow portion.

[0022] In the example shown in FIG. 1, the hollow shaft MS2 of the hand driving motor M2 passes through the hand driving motor M1 and the hollow shaft MS1. The second arm 12 incorporates the hand driving motor M1 and the hand driving motor M2 with the hollow shaft MS1 and the hollow shaft MS2 protruding from the upper surface side of the second arm 12. The hand 13A is connected to the hollow shaft MS1, and the hand 13B is connected to the hollow shaft MS2. That is, the hollow shaft MS2, which is the inner hollow shaft MS, rotates the hand 13B, which is the upper hand 13, and the hollow shaft MS1, which is the outer hollow shaft MS, rotates the hand 13A, which is the lower hand 13. That is, the hand driving motor M2, which is the lower hand driving motor M, rotates the hand 13B, which is the upper hand 13, and the hand driving motor M1, which is the upper hand driving motor M, rotates the hand 13A, which is the lower hand 13.

[0023] In other words, hand drive motor M1 directly drives hand 13A, and hand drive motor M2 directly drives hand 13B, without going through a mechanism that transmits driving force such as a belt. When there are three or more hands 13, hand drive motors M in the same number as the number of hands 13 are built into second arm 12 with motor shafts AH concentrically arranged.

[0024] Here, the hand drive motor M may be a so-called radial gap motor or an axial gap motor. A radial gap motor refers to a motor in which a rotor and a stator face each other in the radial direction of the motor axis AH. An axial gap motor refers to a motor in which a rotor and a stator face each other in the direction along the motor axis AH. Note that an axial gap motor can be made thinner than a radial gap motor, that is, the height of the motor can be reduced, and is therefore preferable in terms of making the second arm 12 thinner.

[0025] Furthermore, when the hand drive motor M is a radial gap type built-in motor, the motor stator is usually shrink-fitted into the arm. On the other hand, when the hand drive motor M is an axial gap type built-in motor, the motor stator can be fixed to the arm with bolts or the like in a direction along the motor axis AH. Therefore, from the standpoint of reducing assembly man-hours, it is preferable to use an axial gap motor for the hand drive motor M.

[0026] The hand drive motor M may be a motor having a case that covers a rotor and a stator, or may be a so-called built-in motor that is attached directly to the frame of the second arm 12 without having a case.

[0027] As shown in S1 of FIG. 1, the second arm 12 incorporates multiple hand drive motors M with their encoders ME facing each other. That is, the multiple hand drive motors M each have an encoder ME on one side in the direction along the motor axis AH, and are incorporated in one arm with the encoders ME facing each other. In this way, by arranging the multiple hand drive motors M with the encoders ME provided on the end faces of the hand drive motors M facing each other, the wiring of the encoders ME can be gathered in close proximity to each other. Also, the space required for the wiring can be reduced. This makes it possible to miniaturize the arm.

[0028] The second arm 12 also houses multiple hand drive motors M, with the hollow shaft MS of one of the hand drive motors M inserted into the hollow shaft MS of the other hand drive motors M. In other words, the multiple hand drive motors M include hollow shafts MS connected to rotors and extending along the motor axis AH, and are built into one arm with the hollow shaft MS of one of the hand drive motors M inserted into the hollow shaft MS of the other hand drive motors M.

[0029] In this way, by arranging the hollow shafts MS of the multiple hand driving motors M nested together, it is possible to reduce the space required to accommodate the hand driving motors M. This makes it possible to reduce the size of the arm.

[0030] The case where the hand drive motor M is an axial gap motor will be described later with reference to FIGS.

[0031] Next, the configuration of the transport robot 10 will be further described with reference to Fig. 2. Fig. 2 is a perspective view of the transport robot 10. As shown in the figure, the transport robot 10 includes a main body unit 15, a lift unit 16, a first arm 11, a second arm 12, and a plurality of hands 13.

[0032] 2 illustrates an example of the transport robot 10 having two hands 13A and 13B, but the number of hands 13 may be any number. In addition, it is preferable that the lift axis A0, the first axis A1, the second axis A2, and the motor axis AH shown in the figure are parallel to each other.

[0033] The main body 15 incorporates a mechanism for raising and lowering the lifting unit 16. The lifting unit 16 rises and falls along a lifting axis A0 shown in the figure, and supports the base end side of the first arm 11 so as to be rotatable about a first axis A1. Note that the lifting unit 16 itself may be rotated about the first axis A1.

[0034] The first arm 11 supports the base end side of the second arm 12 at the tip side so as to be rotatable about the second axis A2. The second arm 12 supports the base end sides of the hands 13A and 13B at the tip side so as to be rotatable about the motor axis AH. The hands 13A and 13B include a base portion 13a and a fork portion 13b.

[0035] Thus, the transport robot 10 is a three-link horizontal articulated robot consisting of the first arm 11, the second arm 12, and the hand 13. As described above, the transport robot 10 has a lifting mechanism, so that it can access objects to be transported, such as substrates, that are located at different heights. Note that the first arm 11 may be omitted, and the robot may be a two-link horizontal articulated robot consisting of the second arm 12 and the hand 13.

[0036] Next, the appearance of the first arm 11, the second arm 12, and the hand 13 will be described with reference to Fig. 3. Fig. 3 is a schematic side view of the first arm 11, the second arm 12, and the hand 13. Note that Fig. 3 shows the first arm 11, the second arm 12, and the hand 13 in a folded position.

[0037] For reference, the figure also shows the first axis A1, the second axis A2, and the motor axis AH shown in Figure 2. Note that the "folded position" refers to a position in which the tip side of the second arm 12 faces the base end side of the first arm 11, and the tip side of the hand 13 faces the base end side of the second arm 12.

[0038] 3, the bottom side of the first arm 11 is substantially flat. On the other hand, the top side has a stepped shape in which the top surface of the end on the second axis A2 side is higher than the top surface of the end on the first axis A1 side. The reason why the top surface of the end on the second axis A2 side protrudes towards the second arm 12 side in this manner is because a motor that drives the second arm 12 is built into the first arm 11.

[0039] 3, the top surface of the second arm 12 is substantially flat. On the other hand, the bottom surface of the second arm 12 is stepped, with the lower surface of the end portion on the second axis A2 side being higher than the bottom surface of the other end portion. In this manner, the bottom surface of the end portion on the second axis A2 side is recessed more than the bottom surface of the other end portion in order to avoid the protruding shape of the first arm 11 described above.

[0040] Thus, in side view, second arm 12 has a shape in which the thickness at the other end side is greater than the thickness at the end side corresponding to second axis A2, and protrudes toward first arm 11. Therefore, the volume of the thicker portion can be made large, making it easy to ensure space for storing hand drive motors M (see FIG. 1) that drive hands 13 in line along motor axis AH.

[0041] A hand 13 is provided on the upper surface of the end portion opposite to the end portion on the second axis A2 side of the second arm 12. Two hands 13, hand 13A and hand 13B, are provided in this order along the motor axis AH when viewed from the second arm 12.

[0042] Second arm 12 is disassembled and can be constructed by attaching multiple separate sub-frames to a base frame, but this will be described later with reference to Figures 5A and 5B.

[0043] Next, a case in which the encoder ME of each hand drive motor M is shaped to fit within a semicircular outer shape will be described with reference to Figures 4A and 4B. Figure 4A is a schematic side view of multiple hand drive motors M combined, and Figure 4B is a schematic top view of the same.

[0044] Here, in FIGS. 4A and 4B, the encoders ME are different from those shown in FIG. 1 in that each encoder ME has a shape that fits within a semicircular disk-like outer shape and is arranged at the same height in the direction along the motor shaft AH.

[0045] The encoder ME also includes a disk-shaped portion fixed to the end face of the rotor of the hand drive motor M, and a detector shaped to fit within a semicircular outline obtained by dividing the disk portion into equal parts. For ease of explanation, the disk portion is omitted in Figures 4A and 4B, and only the detector is shown. The outline of the disk portion is assumed to be the same as the outline of the end face of each hand drive motor M.

[0046] As shown in FIG. 4A, the encoder ME1 of the hand driving motor M1 and the encoder ME2 of the hand driving motor M2 are arranged so that they at least partially overlap in the direction along the motor shaft AH. From the viewpoint of reducing the height, it is more preferable to arrange the encoders ME1 and ME2 at approximately the same height. Also, in FIG. 4A and FIG. 4B, an example is shown in which the encoder ME1 is arranged on the positive side of the motor shaft AH in the Y-axis direction, and the encoder ME2 is arranged on the negative side of the Y-axis direction. However, this is not a limitation, and the encoders ME1 and ME2 may be arranged at positions rotated by any angle around the motor shaft AH.

[0047] As shown in Figure 4B, the encoder ME1 of the hand drive motor M1 and the encoder ME2 of the hand drive motor M2 are oriented so that their sides face each other across the motor shaft AH. In other words, the multiple hand drive motors M are built into one arm with the end faces of the disk parts of the encoders ME that they each have facing each other across the detection unit, and with the sides of the detection units facing each other across the motor shaft AH (see Figure 1). Note that the shape of each encoder ME can be any shape, such as a sector or an irregular shape, as long as it can be arranged in an area corresponding to a semicircle.

[0048] In this way, by making the encoders ME have a shape that fits within the semicircular outline and by arranging them facing each other across the motor shaft AH, the height of the assembled multiple hand drive motors M can be reduced as a whole, thereby making it possible to make the arm thinner.

[0049] Next, the configuration of second arm 12 shown in Fig. 3 etc. will be described with reference to Fig. 5A and Fig. 5B. Fig. 5A is a schematic side view showing subframe 12S incorporating a motor, and Fig. 5B is a schematic side view showing the arm after assembly.

[0050] As shown in Fig. 5A, subframe 12S1, which is one of the subframes 12S, houses a hand driving motor M1. Subframe 12S2 houses a hand driving motor M2. A hollow shaft MS1 of the hand driving motor M1 protrudes from subframe 12S1 along a motor axis AH. A hollow shaft MS2 of the hand driving motor M2 protrudes from subframe 12S2 along a motor axis AH.

[0051] Here, for example, by moving subframe 12S1 in direction S31, hollow shaft MS2 of hand drive motor M2 can be inserted into the hollow portion of hand drive motor M1. Then, subframe 12S1 and subframe 12S2 can be assembled by fixing the bottom surface of subframe 12S1 and the top surface of subframe 12S2 in contact with each other. Note that, in the assembled state, the tip of hollow shaft MS2 protrudes from the tip of hollow shaft MS1.

[0052] That is, the second arm 12 (see FIG. 3) can be separated into multiple sub-frames 12S along the motor axis AH on the side supporting the multiple hands 13, and each hand drive motor M is fixed to each sub-frame 12S shown in FIG. 5A one by one. That is, the second arm 12 has multiple sub-frames 12S that can be disassembled along the motor axis AH on the multiple hands 13 side. Each sub-frame 12S incorporates one of the multiple hand drive motors M. In this way, by incorporating the hand drive motors M into each of the separate sub-frames 12S, the arm can be easily assembled.

[0053] Furthermore, as shown in FIG. 5B, subframe 12S1 and subframe 12S2 in the assembled state are moved toward base frame 12B of second arm 12 (see direction S32), thereby assembling subframe 12S incorporating a motor to base frame 12B.

[0054] Moreover, the subframe 12S3 is assembled from above to the base frame 12B (see the direction S33), thereby completing the second arm 12. The subframe 12S3 is a unit that does not incorporate the hand drive motor M. The configuration of the subframe 12S3 will be described later with reference to FIG.

[0055] Here, the outer shape of each of the multiple sub-frames 12S is a shape that forms part of the outer shape of the second arm 12. In other words, the multiple sub-frames 12S each have an outer surface that forms the outer shape of the second arm 12. Furthermore, when sub-frames 12S1 and 12S2 that house hand driving motors M are stacked such that the motor shafts AH of the hand driving motors M are concentric, they form the outer shape of the side where second arm 12 supports hand 13 (see FIG. 3).

[0056] In this way, by making the outer shape of each subframe 12S into a shape that becomes part of the outer shape of the second arm 12 when assembled, the number of parts of the second arm 12 can be reduced, making it possible to make the second arm 12 smaller.

[0057] Next, the configuration of the subframe 12S3 shown in Fig. 5B will be described with reference to Fig. 6. Fig. 6 is a schematic perspective view showing a subframe 12S that does not incorporate a motor. Note that Fig. 6 shows a state in which the top cover has been removed in order to show the internal configuration of the subframe 12S.

[0058] As shown in Fig. 6, the subframe 12S3 is a unit that houses the cable C13B connected to the hand 13B (see Fig. 3). When the hand 13B rotates, the cable C13B is wound around the rotation axis of the hand 13B. Here, a necessary and sufficient length of the cable C13B is housed in the subframe 12S so that the hand 13B has a sufficient rotation angle.

[0059] For example, as shown in FIG. 6, by storing the cable C13B in the subframe 12S in a position where it is bent into an S-shape or an inverted S-shape when viewed from above, a sufficient length can be ensured.

[0060] 5B, the hand drive motor M is a so-called direct drive motor, so there is no need to provide a mechanism for transmitting a drive force, such as a belt, to the second arm 12. Therefore, the volume of the subframe 12S can be made larger than in the case of belt drive, and the length of the cable C13B that can be accommodated can be made longer.

[0061] This contributes to an expansion of the rotation angle range of the hand 13B (see FIG. 3). Also, by using a direct drive motor as the hand drive motor M instead of a belt drive, it becomes easier to change the design to change the arm length of the second arm 12.

[0062] Next, a case where the hand drive motor M shown in Fig. 1 etc. is an axial gap motor will be described with reference to Figs. 7 to 9. Fig. 7 is an exploded perspective view of the first motor unit 100, and Fig. 8 is an exploded perspective view of the second motor unit 200. Also, Fig. 9 is a schematic side cross-sectional view of the second arm 12 after assembly.

[0063] As shown in Fig. 7, the first motor unit 100 includes a first motor 101 that corresponds to the hand drive motor M1 shown in Fig. 1 etc., and a subframe 12S1 shown in Fig. 5A etc. The upper and lower surfaces of the subframe 12S1 are open, but a removable cover is provided on the upper surface.

[0064] In addition, a communication hole can be appropriately provided on the side surface of the subframe 12S1 that is connected to the base frame 12B (see FIG. 5B). In addition, in FIG. 7, the inner wall provided inside the subframe 12S1 and to which each component of the first motor 101 is attached is omitted.

[0065] The first motor 101 includes a stator 110 and a rotor 120 that respectively correspond to the stator and rotor of an axial gap motor. The first motor 101 also includes a hollow shaft 121 and a boss 122 that correspond to the hollow shaft MS1 shown in FIG. 1 etc., a bearing 140, and a bearing presser 141.

[0066] The first motor 101 also includes an encoder 130 that corresponds to the encoder ME1 shown in FIG.

[0067] Stator 110 is disk-shaped with a hollow portion along motor shaft AH, and is provided with teeth and windings wound around the teeth on the end surface facing rotor 120. Stator 110 is molded after windings are wound around the teeth. Rotor 120 faces the end surface of stator 110 and has a hollow portion that communicates with the hollow portion of stator 110.

[0068] A plurality of magnets are provided along the circumferential direction on the end face of the rotor 120 facing the stator 110. A disk portion 131 of the encoder 130 is fixed to the other end face of the rotor 120. The disk portion 131 also has a hollow portion that communicates with the hollow portion of the rotor 120.

[0069] 7, hollow shaft 121 is fixed to the upper surface of rotor 120. Stator 110 is disposed such that the inner circumference is spaced apart from the outer circumference of hollow shaft 121. Bearing 140 is a so-called cross roller bearing. By using a cross roller bearing for bearing 140, it is possible to achieve both high rigidity and compact size.

[0070] For example, the inner circumference side of bearing 140 is fixed to the outer circumference of hollow shaft 121, and the outer circumference side of bearing 140 is fixed to subframe 12S1 by bearing presser 141. Note that the inner wall of subframe 12S1 to which bearing 140 is fixed is omitted in Fig. 7. Also, boss 122 is fixed to the upper surface of hollow shaft 121 so that the hollow portion of hollow shaft 121 communicates with the hollow portion.

[0071] The detection unit 132 of the encoder 130 is disposed so that its end face faces an end face of a disk unit 131 provided on an end face of the rotor 120. The support unit 133 supports the other end face side of the detection unit 132, and is fixed to the subframe 12S1. Note that the support unit 133 may be shaped so as to be fixable to the stator 110, and may be fixed to the stator 110.

[0072] Thus, the first motor 101 includes the disk-shaped stator 110 having a hollow portion along the motor axis AH, and the disk-shaped rotor 120 having a hollow portion and an end face facing the end face of the stator 110.

[0073] The first motor 101 is connected to the rotor 120 so as to communicate with the hollow portion of the rotor 120, and includes a hollow shaft 121 and a boss 122 that extend along the motor axis AH. The hollow shaft 121 of the first motor 101 is provided on the stator 110 side of the rotor 120, and extends along the motor axis AH, penetrating the hollow portion of the stator 110.

[0074] As shown in FIG. 7, by making the stator 110, rotor 120, hollow shaft 121 and boss 122 hollow, wiring and the shaft of a motor of another unit can be placed inside the hollow space, making it possible to miniaturize the arm.

[0075] As shown in Fig. 8, the second motor unit 200 includes a second motor 201 that corresponds to the hand drive motor M2 shown in Fig. 1 etc., and a subframe 12S2 shown in Fig. 5A etc. The top surface of the subframe 12S2 is open. A removable cover may be provided on the top surface.

[0076] In addition, a communication hole can be appropriately provided on the side surface of the subframe 12S2 that is connected to the base frame 12B (see FIG. 5B). In addition, in FIG. 8, the illustration of the inner wall provided inside the subframe 12S2 and to which each component of the second motor 201 is attached is omitted.

[0077] The second motor 201 includes a stator 210 and a rotor 220 that respectively correspond to the stator and rotor of an axial gap motor. The second motor 201 also includes a hollow shaft 221 that corresponds to the hollow shaft MS2 shown in FIG. 1 etc., a bearing 240, an outer periphery holder 241, and an inner periphery holder 242. The outer periphery holder 241 is a component that holds the outer periphery of the bearing 240, and the inner periphery holder 242 is a component that holds the inner periphery of the bearing 240.

[0078] The second motor 201 also includes an encoder 230 that corresponds to the encoder ME2 shown in FIG.

[0079] Stator 210 is disk-shaped with a hollow portion along motor shaft AH, and has teeth and windings wound on its end surface on the rotor 220 side. Stator 210 is molded after windings are wound around the teeth. Rotor 220 has an end surface facing stator 210 and has a hollow portion communicating with the hollow portion of stator 210.

[0080] A plurality of magnets are provided along the circumferential direction on the end face of rotor 220 facing stator 210. A disk portion 231 of encoder 230 is fixed to the other end face of rotor 220. A hollow portion through which hollow shaft 221 passes is provided in disk portion 231.

[0081] 8, hollow shaft 221 is fixed to the upper surface of rotor 220. Bearing 240 is a so-called cross roller bearing. By using a cross roller bearing as bearing 240, it is possible to achieve both high rigidity and compactness. For example, the inner periphery side of bearing 240 is fixed to the outer periphery of hollow shaft 221 by inner periphery holder 242, and the outer periphery side of bearing 240 is fixed to subframe 12S2 by outer periphery holder 241.

[0082] Detection unit 232 of encoder 230 is disposed so that its end face faces an end face of disk unit 231 provided on an end face of rotor 220. Support unit 233 supports the other end face side of detection unit 232, and is fixed to subframe 12S2. Note that support unit 233 may be shaped so as to be fixable to stator 210, and may be fixed to stator 210.

[0083] Thus, the second motor 201 includes a disk-shaped stator 210 having a hollow portion along the motor axis AH, and a disk-shaped rotor 220 having a hollow portion and an end face facing an end face of the stator 210.

[0084] The second motor 201 is connected to the rotor 220 so as to communicate with the hollow portion of the rotor 220, and includes a hollow shaft 221 extending along the motor axis AH. The hollow shaft 221 of the second motor 201 is fixed to an end face of the rotor 220 opposite to the stator 210, and extends along the motor axis AH in a direction away from the stator 210.

[0085] As shown in FIG. 8, by making the stator 210, rotor 220, and hollow shaft 221 hollow, wiring and the shaft of a motor of another unit can be arranged inside the hollow space, making it possible to reduce the size of the arm.

[0086] Next, the second arm 12 in a state where the first motor unit 100 shown in Fig. 7 and the second motor unit 200 shown in Fig. 8 are assembled will be described with reference to Fig. 9. Fig. 9 is a schematic side cross-sectional view of the second arm 12 after assembly. Note that Fig. 9 corresponds to a cross-sectional view taken along a plane parallel to the YZ plane at the position of the motor axis AH when looking at the second arm 12 from the tip end side to the base end side. In the following description, the configurations described in Figs. 7 and 8 will be omitted as appropriate.

[0087] As shown in Fig. 9, the first motor unit 100 and the second motor unit 200 are symmetrical with respect to the motor axis AH, except for the encoders ME1 and ME2. The encoders ME1 and ME2 are located opposite each other with respect to the motor axis AH. Note that Fig. 9 omits the illustration of the inner walls of the subframes 12S1 and 12S2 to which the encoders ME1 and ME2 are respectively fixed.

[0088] The boss 122 of the first motor unit 100 protrudes from the upper surface of the second arm 12. In addition, the hollow shaft 221 of the second motor unit 200 passes through the hollow portion of the first motor unit 100 and protrudes from the upper surface of the second arm 12.

[0089] Here, the stator 210, rotor 220, rotor 120, and stator 110 of the second motor 201, the first motor 101, and the second arm 12 are arranged in this order from the lower surface to the upper surface along the motor shaft AH.

[0090] Further, the encoder ME1 of the first motor unit 100 is disposed at a position facing the lower surface side of the rotor 120 in the first motor unit 100, and the encoder ME2 of the second motor unit 200 is disposed at a position facing the upper surface side of the rotor 220 in the second motor unit 200. As shown in Fig. 9, the encoder ME1 and the encoder ME2 are disposed at approximately the same height in the direction along the motor axis AH.

[0091] In this manner, the first motor 101, which is one of the hand drive motors M, has the hollow shaft 121 and boss 122 that constitute the hollow shaft extending through the hollow portion of the stator 110 in the first motor 101. Also, the second motor 201, which is one of the hand drive motors M, has the hollow shaft 221 extending in a direction away from the stator 210 in the second motor 201.

[0092] The second arm 12 incorporates the first motor 101 and the second motor 201, respectively, in a position where the hollow shaft 221 extending in a direction away from the stator 210 penetrates the hollow shaft 121 and the boss 122 that extend through the hollow portion of the stator 110. In other words, the hollow shaft 221 extending in a direction away from the stator 210 is incorporated in one arm in a position where it penetrates the hollow shaft 121 that extends through the hollow portion of the stator 110.

[0093] In this manner, the first motor 101 and the second motor 201 are disposed so that the hollow shaft 221 extending in a direction away from the stator 210 passes through the hollow shaft 121 extending through the hollow portion of the stator 110. In this manner, the height of the second arm 12 incorporating these motors can be reduced.

[0094] 9, the first motor 101 and the second motor 201 have a hollow portion that penetrates from the lower surface side to the upper surface side of the second arm 12 along the motor shaft AH. In such a hollow portion, for example, a cable for the hand 13B (see FIG. 3) connected to the hollow shaft 221 of the second motor unit 200 can be routed.

[0095] Although FIG. 9 shows the case where the hollow shafts of two motors are nested, when three or more motors are arranged coaxially, it is sufficient to arrange the motors so that they include at least one of the nested arrangements shown in FIG. 9.

[0096] Next, a robot system 1 including a transport robot 10 and a control device 20 that controls the operation of the transport robot 10 will be described with reference to Fig. 10. Fig. 10 is a block diagram of the robot system 1. Since the configuration of the transport robot 10 has already been described, the configuration of the control device 20 will be mainly described below. Note that an input terminal device such as a pendant connected to the control device 20 is omitted in Fig. 10.

[0097] 10, the control device 20 includes a control unit 21 and a storage unit 22. The control unit 21 includes an operation control unit 21a. The storage unit 22 stores teaching data 22a. The control device 20 is connected to the transfer robot 10.

[0098] Here, the control device 20 includes, for example, a computer and various circuits having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a HDD (Hard Disk Drive), an input / output port, etc. The CPU of the computer functions as the operation control unit 21a of the control unit 21, for example, by reading and executing a program stored in the ROM.

[0099] Moreover, the operation control unit 21a of the control unit 21 can be configured with hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0100] The storage unit 22 corresponds to, for example, a RAM or a HDD. The RAM or HDD can store the teaching data 22a. The control device 20 may acquire the above-mentioned programs and various information via other computers or portable recording media connected via a wired or wireless network.

[0101] The control unit 21 of the control device 20 controls the operation of the transport robot 10 based on the teaching data 22a, and also performs processing to suppress the operation of the transport robot 10 when an error occurs in the operation of the transport robot 10.

[0102] The operation control unit 21a controls the operation of the transport robot 10 based on the teaching data 22a. Specifically, the operation control unit 21a causes the transport robot 10 to transport an object to be transported, such as a substrate, by issuing instructions to the motors corresponding to each axis of the transport robot 10 based on the teaching data 22a stored in the storage unit 22. The operation control unit 21a also improves the operation accuracy of the transport robot 10 by performing feedback control using the encoder values ​​of the motors.

[0103] The teaching data 22a is generated in a teaching stage in which the transport robot 10 is taught how to operate, and is information including a "job" that specifies the operation of the transport robot 10, including the movement trajectory of the hand 13 (see FIG. 1). Note that the teaching data 22a generated by another computer connected via a wired or wireless network may be stored in the storage unit 22.

[0104] As described above, the transfer robot 10 according to this embodiment includes a plurality of hands 13 and a second arm 12. The plurality of hands 13 can hold an object to be transferred and rotate coaxially. The second arm 12 supports the plurality of hands 13. The second arm 12 supports the plurality of hands 13 on the upper surface at the tip side, and incorporates a plurality of hand drive motors M that directly drive the plurality of hands 13, aligned concentrically with the motor shaft AH and oriented along the motor shaft AH.

[0105] In this way, by incorporating multiple hand drive motors M, which respectively directly drive the hands 13, in the arm in a position aligned along the motor shaft AH and concentrically about the motor shaft AH, it is possible to reduce the space required to accommodate the hand drive motors M. This makes it possible to reduce the size of the arm.

[0106] Further advantages and modifications may readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof. [Explanation of symbols]

[0107] 1. Robot System 10. Transport Robot 11 First Arm 12 Second Arm 12B Base Frame 12S subframe 13 Hands 15 Main body 16 Lifting section 20 Control device 21 Control section 21a Operation control section 22 Memory section 22a Teaching Data 100 First motor unit 101 First motor 110 Stator 120 rotor 121 Hollow Shaft 122 Boss 130 Encoder 131 Disk section 132 Detection unit 133 Support part 140 Bearing 141 Bearing holder 200 Second motor unit 201 Second Motor 210 Stator 220 Rotor 221 Hollow Shaft 230 Encoder 231 Disk section 232 Detection unit 233 Support part 240 Bearing 241 Outer circumference clamp 242 Inner circumference clamp A0 Lifting axis A1 First axis A2 2nd axis AH motor shaft M Hand drive motor ME Encoder MS Hollow Shaft

Claims

1. a plurality of hands capable of holding an object to be transferred and each of which rotates about a single rotation axis; a plurality of hand drive motors, the motor shafts to which the plurality of hands are respectively connected being arranged concentrically about the pivot shaft in a direction along the pivot shaft, the hand drive motors directly driving the plurality of hands, One arm incorporating the plurality of hand drive motors; Equipped with The one arm is a plurality of subframes disassembled along the motor shaft at the plurality of hand sides; The plurality of subframes include: Each of the plurality of hand drive motors is built in, and each has an outer surface that constitutes the outer shape of one of the arms on the side of the plurality of hands. A transport robot characterized by the above.

2. The plurality of hand drive motors include An encoder is provided on each surface on one side in the direction along the motor shaft, and the encoders are built into one of the arms in a position facing each other. The transport robot according to claim 1 .

3. The encoder comprises: a disk portion fixed to an end surface of a rotor of the hand drive motor; a detection unit that is fixed to the stator or the arm of the hand drive motor, that faces an end face of the disk unit, and that is shaped to fit within a semicircular outer shape obtained by equally dividing the disk unit; Including, The plurality of hand drive motors include The encoders are built into one arm in such a manner that end faces of the disk parts face each other across the detection part, and side faces of the detection parts face each other across the motor shaft.

3. The transport robot according to claim 2 .

4. The hand drive motor is The motor includes a hollow shaft connected to a rotor and extending along the motor axis, and the hollow shaft of one of the hand drive motors is built into one of the arms in a position where it is inserted into the hollow shaft of the other hand drive motor. The transport robot according to claim 1 .

5. The inner hollow shaft rotates the upper hand, and the outer hollow shaft rotates the lower hand. The transport robot according to claim 4 .

6. The hand drive motor is It is an axial gap type motor. The transport robot according to any one of claims 1 to 5,

7. The hand drive motor is a disk-shaped stator having a hollow portion along the motor shaft; a disk-shaped rotor having an end face facing an end face of the stator and having the hollow portion; a hollow shaft connected to the rotor so as to communicate with the hollow portion of the rotor and extending along the motor shaft; The transport robot according to claim 6 , further comprising:

8. At least one of the plurality of hand drive motors is the hollow shaft extends through a hollow portion of the stator of the hand drive motor, At least one of the other hand drive motors is the hollow shaft extends in a direction away from the stator of the hand drive motor, The hollow shaft extending in a direction away from the stator is built into one of the arms in such a position that the hollow shaft extends through a hollow portion of the stator. The transport robot according to claim 7 .

9. The transport robot according to claim 1 ; A control device for controlling the operation of the transport robot; A robot system comprising:

10. a plurality of hands capable of holding an object to be transferred and each of which rotates about a single rotation axis; a plurality of hand drive motors, the motor shafts to which the plurality of hands are respectively connected being arranged concentrically about the pivot shaft in a direction along the pivot shaft, the hand drive motors directly driving the plurality of hands, One arm incorporating the plurality of hand drive motors; Equipped with The plurality of hand drive motors include an encoder is provided on one surface in a direction along the motor shaft, and the encoders are built into one of the arms in a position where they face each other; The encoder comprises: a disk portion fixed to an end surface of a rotor of the hand drive motor; a detection unit that is fixed to the stator or the arm of the hand drive motor, that faces an end face of the disk unit, and that is shaped to fit within a semicircular outer shape obtained by equally dividing the disk unit; Including, The plurality of hand drive motors include The encoders are built into one arm in such a manner that end faces of the disk parts face each other across the detection part, and side faces of the detection parts face each other across the motor shaft. A transport robot characterized by the above.

Images