Belt transmission mechanism and transfer robot provided with same

Abstract

The invention provides a belt transmission mechanism and a transfer robot. The belt transmission mechanism is provided with two steel belts, the winding directions of which are opposite to each other relative to the two belt wheels, and the rotation angle of the belt wheels can be enlarged. The present invention is provided with: pulleys (6A, 6B); a steel strip having both ends (711, 712) and both ends (721, 722); and covers (91, 92). The pulley (6A) has recessed portions (61, 62) that are recessed from the outer peripheral surface of the pulley (6A). A block member (81) is fixed to the end portion (711), and the block member (81) is disposed in the recess (61). The cover (91) is fixedly disposed in the recess (61) so as to surround the block member (81), and has an outer peripheral surface having the same diameter as the outer peripheral surface of the pulley (6A). A block member (82) is fixed to the end portion (721), and the block member (82) is disposed in the recess (62). The cover (92) is fixedly disposed in the recess (62) so as to surround the block member (82), and has an outer peripheral surface having the same diameter as the outer peripheral surface of the pulley (6A).

Description

Technical Field

[0001] The present disclosure relates to a belt drive mechanism and a handling robot including the belt drive mechanism. Background Art

[0002] Among handling robots, there is a handling robot including a horizontally articulated arm mechanism. As such a handling robot, for example, there is a handling robot disclosed in Patent Document 1 below. This handling robot includes an arm that can be rotatably attached to each other and a hand that can be rotatably attached to the end of the arm. The arm and the hand are rotationally driven by a belt drive device. In Patent Document 1, a metal steel belt is used as the belt constituting the belt drive device. Compared with, for example, a rubber synchronous belt, the steel belt emits less dust and exhaust gas, and the belt drive device using the steel belt is suitable for being assembled in a handling robot arranged in a vacuum environment.

[0003] In the belt drive device disclosed in Patent Document 1, two steel belts are provided with respect to two pulleys (a driving pulley and a driven pulley). Each of the two steel belts is not an endless belt but an end belt having two end portions. The two steel belts are mounted at different upper and lower heights with respect to the two pulleys (see Figure 1 of the same document). Further, the two steel belts are mounted with opposite winding directions with respect to the two pulleys (see Figure 2 of the same document). By mounting the two end belts in this way, the pulley can be rotated in both rotational directions about the axis. Both end portions of each steel belt are fastened to the pulley by a press-in pin, a threaded member, etc. in a state of being along the outer peripheral surface of the pulley. In the belt drive device having a structure in which both end portions of such an end belt are fastened to the pulley, the positioning accuracy is better than that of an endless belt, and the position shift with respect to the pulley can be suppressed.

[0004] However, in the above-described conventional belt drive mechanism, overlapping of the steel belt (end belt) on the outer periphery of the pulley is not allowed, and there is a limit to the rotation angle of the pulley. Further, for the belt wound around the pulley, interference with the fastening portion at the end of the belt needs to be avoided, and thus the rotation angle of the pulley is further limited.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2008-223974 Summary of the Invention

[0008] -Problems to be Solved by the Invention-

[0009] The present disclosure is made in view of such a situation, and its main problem is to provide a belt drive mechanism that is configured to include two steel belts mounted on two pulleys with opposite winding directions, and is a structure that can expand the rotation angle of the pulleys.

[0010] In order to solve the above problems, in the present disclosure, the following technical means are adopted.

[0011] The belt drive mechanism provided by the first aspect of the present disclosure includes: a first pulley and a second pulley, which are configured to be rotatable about a pair of axes parallel to each other respectively; a first steel belt, having a first end portion mounted on the first pulley and a second end portion mounted on the second pulley, and wound around the first pulley and the second pulley; a second steel belt, having a third end portion mounted on the first pulley and a fourth end portion mounted on the second pulley, and being separated and arranged in the axial direction of the first pulley and the second pulley with respect to the first steel belt, and wound around the first pulley and the second pulley so as to have a winding direction opposite to that of the first steel belt; a first cover; and a second cover, the first pulley has a first recess and a second recess respectively recessed from the outer peripheral surface, a first block member is fixed to the first end portion and is disposed in the first recess, and the first cover is fixedly disposed in the first recess so as to surround the first block member and has a first outer peripheral surface having the same diameter as the outer peripheral surface of the first pulley, a second block member is fixed to the third end portion and is disposed in the second recess, and the second cover is fixedly disposed in the second recess so as to surround the second block member and has a second outer peripheral surface having the same diameter as the outer peripheral surface of the first pulley.

[0012] In a preferred embodiment, a third cover and a fourth cover are further included, the second pulley has a third recess and a fourth recess respectively recessed from the outer peripheral surface, a third block member is fixed to the second end portion and is disposed in the third recess, and the third cover is fixedly disposed in the third recess so as to surround the third block member and has a third outer peripheral surface having the same diameter as the outer peripheral surface of the second pulley, a fourth block member is fixed to the fourth end portion and is disposed in the fourth recess, and the fourth cover is fixedly disposed in the fourth recess so as to surround the fourth block member and has a fourth outer peripheral surface having the same diameter as the outer peripheral surface of the second pulley.

[0013] In a preferred embodiment, a belt tension adjustment portion capable of pressing the corresponding first block member or the second block member toward the circumferential direction of the first pulley is provided on at least one of the first cover and the second cover.

[0014] In a preferred embodiment, the first concave portion has a first guiding surface that abuts against the first steel belt and is smoothly connected to the outer peripheral surface of the first pulley, and the second concave portion has a second guiding surface that abuts against the second steel belt and is smoothly connected to the outer peripheral surface of the first pulley.

[0015] The transfer robot provided by the second aspect of the present disclosure includes: a belt drive mechanism provided by the first aspect of the present disclosure; and a horizontally articulated arm mechanism having an arm that rotates by the belt drive mechanism.

[0016] -Advantages of the Invention-

[0017] According to the belt drive mechanism of the present disclosure, the first steel belt can span the outer peripheral surface of the first pulley and the first outer peripheral surface of the first cover and wind approximately one full turn (about 360°) in the circumferential direction of the first pulley. In addition, the second steel belt can span the outer peripheral surface of the first pulley and the second outer peripheral surface of the second cover and wind approximately one full turn (about 360°) in the circumferential direction of the first pulley. Therefore, the rotation angle of the first pulley can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a top view showing an example of a transfer robot including the belt drive mechanism of the present disclosure.

[0019] Figure 2 is showing Figure 1 a longitudinal sectional view of the schematic structure of the transfer robot shown.

[0020] Figure 3 is a top view showing an example of the schematic structure of the belt drive mechanism.

[0021] Figure 4 is along Figure 2 a partial sectional view taken along line IV-IV.

[0022] Figure 5 is along Figure 2 a partial sectional view taken along line V-V.

[0023] Figure 6 is along Figure 2 a partial sectional view taken along line VI-VI.

[0024] Figure 7 is along Figure 2 a partial sectional view taken along line VII-VII.

[0025] Figure 8 is schematically showing in Figure 3In the first pulley and the second pulley shown, (a) is a top view of a state in which rotation is maximized in one rotational direction, and (b) is a top view of a state in which rotation is maximized in the other rotational direction. Detailed Implementation Modes

[0026] Hereinafter, preferred implementation modes of the present disclosure will be specifically described with reference to the accompanying drawings.

[0027] In the present disclosure, terms such as "first" and "second" are used only as labels, and it is not necessary to assign a sequence to these objects.

[0028] Figures 1 to 7 An example of a transfer robot including a belt drive mechanism according to the present disclosure is shown. The transfer robot A1 of the present embodiment is used, for example, to transfer thin plate-like workpieces such as circular silicon wafers (not shown). The transfer robot A1 includes a support body 1, a first arm 2, a second arm 3, a hand 4, first pulleys 6A, 6C, 6E, second pulleys 6B, 6D, 6F, a first steel belt 71, a second steel belt 72, a first block member 81, a second block member 82, a third block member 83, a fourth block member 84, a first cover 91, a second cover 92, a third cover 93, and a fourth cover 94.

[0029] The support body 1 is supported by a moving mechanism (not shown) and can move in a given direction within a vertical plane. The structure of the moving mechanism is not particularly limited, and examples thereof may include a structure having a vertical multi-joint type arm mechanism and a slider unit capable of linearly moving in the horizontal direction.

[0030] As Figure 2 shown, the first arm 2 and the second arm 3 are supported by the support body 1 and are horizontal multi-joint type arm mechanisms that move within a horizontal plane. The base end portion ( Figure 2 the right end portion in ) of the first arm 2 is supported so as to be rotatable about a first axis O1 extending in the vertical direction with respect to the support body 1. An opening is formed in the lower wall of the base end portion of the first arm 2, and a cylindrical rotating shaft 50 extending downward from the periphery of the opening is connected to the first arm 2. Although detailed illustration is omitted, a drive source (such as a motor) for rotating the first arm 2 is disposed inside the support body 1, and by driving this drive source, the first arm 2 is rotated about the first axis O1 via the rotating shaft 50. In addition, a rotating shaft 51 and a rotating shaft 52 extending upward from the support body 1 side are inserted through the opening in the lower wall. The rotating shaft 52 is externally fitted to the rotating shaft 51. A bearing (not shown) is interposed between the rotating shaft 51 and the rotating shaft 52. The rotating shaft 51 and the rotating shaft 52 can rotate about the first axis O1.

[0031] At the front end portion of the first arm 2 ( Figure 2An opening is formed in the upper wall of the left end portion of [the relevant part]. In addition, a fixed shaft 53 is provided on the lower wall of the front end portion of the first arm 2. The fixed shaft 53 has a second axis O2 extending in the vertical direction as its central axis, passes through the opening in the upper wall, and extends upward.

[0032] The second arm 3 is supported by the first arm 2. At the base end portion of the second arm 3 ( Figure 2 the right end portion of [the relevant part]), an opening is formed in the lower wall. A cylindrical rotating shaft 54 extending downward from the periphery of the opening is connected to the second arm 3. The rotating shaft 54 is externally fitted to the rotating shaft 55, and the rotating shaft 55 is externally fitted to the fixed shaft 53. Bearings (not shown) are respectively interposed between the fixed shaft 53 and the rotating shaft 55, and between the rotating shaft 55 and the rotating shaft 54. Thus, the rotating shaft 54 can rotate about the second axis O2. With such a structure, the second arm 3 is rotatably supported relative to the front end portion of the first arm 2 ( Figure 2 the left end portion of [the relevant part]) about the second axis O2 extending in the vertical direction. In addition, the fixed shaft 53 provided at the front end portion of the first arm 2 passes through the opening in the lower wall of the second arm 3 and extends into the interior of the second arm 3.

[0033] At the front end portion of the second arm 3 ( Figure 2 the left end portion of [the relevant part]), an opening is formed in the upper wall. In addition, a fixed shaft 56 is provided on the lower wall of the front end portion of the second arm 3. The fixed shaft 56 has a third axis O3 extending in the vertical direction as its central axis, passes through the opening in the upper wall, and extends upward.

[0034] As Figure 1 shown, etc., the front end of the hand 4 is formed in a two-pronged shape and is supported by the second arm 3 in a horizontal posture. The hand 4 is used to place and hold a thin plate-like workpiece (not shown) of a given size such as a circular silicon wafer. As Figure 2 shown, at the base end portion of the hand 4 ( Figure 2 the right end portion of [the relevant part]), a rotating shaft 57 extending downward is connected. The rotating shaft 57 is externally fitted to the fixed shaft 56 provided at the front end portion of the second arm 3, and a bearing (not shown) is interposed between the fixed shaft 56 and the rotating shaft 57. With such a structure, the hand 4 is rotatably supported relative to the front end portion of the second arm 3 about the third axis O3 extending in the vertical direction.

[0035] The first pulleys 6A, 6C, 6E, the second pulleys 6B, 6D, 6F, the first steel belt 71, and the second steel belt 72 rotationally drive the second arm 3 (rotating shaft 54) and the hand 4 (rotating shaft 57). As will be described in detail later, the first steel belt 71 and the second steel belt 72 are each a thin metal sheet strip and are mounted on the first pulleys 6A (6C, 6E) and the second pulleys 6B (6D, 6F). In addition, the first block member 81 and the third block member 83 are mounted on the first steel belt 71, and the second block member 82 and the fourth block member 84 are mounted on the second steel belt 72 (refer to Figure 3 ). The first cover 91 and the second cover 92 are mounted on the first pulleys 6A (6C, 6E), and the third cover 93 and the fourth cover 94 are mounted on the second pulleys 6B (6D, 6F). The first pulleys 6A, 6C, 6E, the second pulleys 6B, 6D, 6F, the first steel belt 71, the second steel belt 72, the first block member 81, the second block member 82, the third block member 83, the fourth block member 84, the first cover 91, the second cover 92, the third cover 93, and the fourth cover 94 constitute the belt drive mechanism of the present disclosure.

[0036] As Figure 2 shown, the first pulley 6A is connected to the upper end of the rotating shaft 51 and can rotate about the first axis O1. The second pulley 6B is connected to the lower end of the rotating shaft 54 and is externally fitted to the rotating shaft 5 and can rotate about the second axis O2. The first steel belt 71 and the second steel belt 72 are each an endless belt having two end portions. The first steel belt 71 and the second steel belt 72 are wound around the first pulley 6A and the second pulley 6B. The second steel belt 72 is located at a position separated from the first steel belt 71 in the axial direction (vertical direction) of the first pulley 6A and the second pulley 6B. In the illustrated example, the second steel belt 72 is located below the first steel belt 71. In addition, as Figure 3 shown, the second steel belt 72 is wound around the first pulley 6A and the second pulley 6B so as to have a winding direction opposite to that of the first steel belt 71. In addition, in Figure 3 , the second steel belt 72 is shown by a dashed line in order to distinguish it from the first steel belt 71. If the rotating shaft 51 is rotated, the first pulley 6A and the second pulley 6B connected to the first pulley 6A via the first steel belt 71 and the second steel belt 72 rotate. And the second arm 3 connected to the second pulley 6B via the rotating shaft 54 rotates about the second axis O2.

[0037] As Figure 2 shown, the first pulley 6C is connected to the upper end of the rotating shaft 52 and can rotate about the first axis O1. The second pulley 6D is connected to the lower end of the rotating shaft 55 and is externally fitted to the fixed shaft 53 and can rotate about the second axis O2. On the first pulley 6C and the second pulley 6D, the first steel belt 71 and the second steel belt 72 are wound in the same manner as on the first pulley 6A and the second pulley 6B.

[0038] The first pulley 6E is connected to the upper end of the rotating shaft 55 and is externally fitted to the fixed shaft 53, and can rotate about the second axis O2. The second pulley 6F is connected to the lower end of the rotating shaft 57 and is externally fitted to the fixed shaft 56, and can rotate about the third axis O3. On the first pulley 6E and the second pulley 6F, the first steel belt 71 and the second steel belt 72 are wound in the same way as on the first pulley 6A and the second pulley 6B. If the rotating shaft 52 is rotated, the first pulley 6C and the second pulley 6D connected to the first pulley 6C via the first steel belt 71 and the second steel belt 72 rotate. Further, if the second pulley 6D rotates, the first pulley 6E connected to the second pulley 6D via the rotating shaft 55 and the second pulley 6F connected to the first pulley 6E via the first steel belt 71 and the second steel belt 72 rotate. And the hand 4 connected to the second pulley 6F via the rotating shaft 57 rotates about the third axis O3.

[0039] Next, with reference to Figures 4 to 7 , the first pulley 6A, the second pulley 6B, the first steel belt 71, the second steel belt 72, the first block member 81, the second block member 82, the third block member 83, the fourth block member 84, the first cover 91, the second cover 92, the third cover 93, and the fourth cover 94 will be specifically described.

[0040] As Figure 4 shown, the first pulley 6A has a first recess 61. The first recess 61 is recessed from the outer peripheral surface 60 and the upper surface of the first pulley 6A, and has a first surface 611 and a first guide surface 612. The first surface 611 is a plane that is in surface contact with the abutting surface 911 of the first cover 91 described later. The first guide surface 612 is a convex curved surface that is smoothly connected to both the outer peripheral surface 60 and the first surface 611 of the first pulley 6A.

[0041] The first block member 81 is fixed to the first end portion 711 which is one end of the first steel belt 71 by appropriate means such as welding. A pair of through holes 811 are formed in the first block member 81. In the first end portion 711, through holes are formed in a region corresponding to the pair of through holes 811. The through holes 811 are elongated holes having the left - right direction in Figure 4 as the long - side direction. Threaded holes are formed in the first surface 611 of the first pulley 6A, and mounting bolts 86 are screwed into the threaded holes through the through holes 811. Thus, the first block member 81 is fixed to the first pulley 6A. The first steel belt 71 wound around the first pulley 6A abuts against the outer peripheral surface 60, the first guide surface 612, and the first surface 611.

[0042] The first cover 91 is disposed in the first recess 61 and has a first outer peripheral surface 910, an abutting surface 911, a retracted surface 912, a recess 913, and working holes 914 and 915. The abutting surface 911 is in surface contact with the first surface 611 of the first pulley 6A. The retracted surface 912 is a surface that retracts slightly upward compared to the abutting surface 911. The dimension by which the retracted surface 912 retracts from the abutting surface 911 is slightly larger than the thickness of the first steel belt 71. Thus, the portion of the first steel belt 71 located between the first surface 611 to the first guiding surface 612 and the retracted surface 912 is slightly separated from the retracted surface 912. The recess 913 is a portion that is recessed upward in Figure 4 , and the first block member 81 is accommodated in the recess 913. The working hole 914 is a through hole that leads from the first outer peripheral surface 910 to the recess 913 and is used to operate the mounting bolt 86 from the outside with a tool. The working hole 915 is used to operate the adjusting screw 97 of the threaded hole mounted on the first cover 91 from the outside. When the adjusting screw 97 is screwed in, the first block member 81 is pressed in the circumferential direction of the first pulley 6A (to the right in Figure 4 ), and the tension of the first steel belt 71 increases. By operating the adjusting screw 97 in this way, the tension of the first steel belt 71 can be adjusted. The working hole 915 and the adjusting screw 97 are an example of the belt tension adjusting portion of the present disclosure. A threaded hole extending along a direction orthogonal to the paper surface of Figure 4 is formed in the first recess 61 of the first pulley 6A, and the mounting bolt 96 is screwed into the threaded hole. Thus, the first cover 91 is fixed to the first pulley 6A so as to surround the first block member 81. Figure 4 The retracted surface 912 is a surface that retracts slightly upward compared to the abutting surface 911. The dimension by which the retracted surface 912 retracts from the abutting surface 911 is slightly larger than the thickness of the first steel belt 71. Thus, the portion of the first steel belt 71 located between the first surface 611 to the first guiding surface 612 and the retracted surface 912 is slightly separated from the retracted surface 912. The recess 913 is a portion that is recessed upward in Figure 4 , and the first block member 81 is accommodated in the recess 913. Figure 4 The recess 913 is a portion that is recessed upward in Figure 4 , and the first block member 81 is accommodated in the recess 913. The working hole 914 is a through hole that leads from the first outer peripheral surface 910 to the recess 913 and is used to operate the mounting bolt 86 from the outside with a tool. The working hole 915 is used to operate the adjusting screw 97 of the threaded hole mounted on the first cover 91 from the outside. When the adjusting screw 97 is screwed in, the first block member 81 is pressed in the circumferential direction of the first pulley 6A (to the right in Figure 4 ), and the tension of the first steel belt 71 increases. By operating the adjusting screw 97 in this way, the tension of the first steel belt 71 can be adjusted. The working hole 915 and the adjusting screw 97 are an example of the belt tension adjusting portion of the present disclosure. A threaded hole extending along a direction orthogonal to the paper surface of Figure 4 is formed in the first recess 61 of the first pulley 6A, and the mounting bolt 96 is screwed into the threaded hole. Thus, the first cover 91 is fixed to the first pulley 6A so as to surround the first block member 81. Figure 4 When the adjusting screw 97 is screwed in, the first block member 81 is pressed in the circumferential direction of the first pulley 6A (to the right in Figure 4 ), and the tension of the first steel belt 71 increases. By operating the adjusting screw 97 in this way, the tension of the first steel belt 71 can be adjusted. The working hole 915 and the adjusting screw 97 are an example of the belt tension adjusting portion of the present disclosure. A threaded hole extending along a direction orthogonal to the paper surface of Figure 4 is formed in the first recess 61 of the first pulley 6A, and the mounting bolt 96 is screwed into the threaded hole. Thus, the first cover 91 is fixed to the first pulley 6A so as to surround the first block member 81. Figure 4 A threaded hole extending along a direction orthogonal to the paper surface of Figure 4 is formed in the first recess 61 of the first pulley 6A, and the mounting bolt 96 is screwed into the threaded hole. Thus, the first cover 91 is fixed to the first pulley 6A so as to surround the first block member 81.

[0043] The diameter of the first outer peripheral surface 910 of the first cover 91 is the same as the diameter of the outer peripheral surface 60 of the first pulley 6A. Here, "the first outer peripheral surface 910 and the outer peripheral surface 60 have the same diameter" means that the first outer peripheral surface 910 is an arc shape having the same radius of curvature as the radius of the outer peripheral surface 60. In the state where the first cover 91 is fixed to the first pulley 6A, the center of the radius of curvature of the first outer peripheral surface 910 coincides with the center of the outer peripheral surface 60, and the outer peripheral surface 60 and the first outer peripheral surface 910 form a series of circumferential shapes with the same diameter. Additionally, in design, the first outer peripheral surface 910 and the outer peripheral surface 60 are set to have the same diameter, but in practice, there may be some errors in the state where the first cover 91 is fixed to the first pulley 6A.

[0044] As Figure 5 shown, the first pulley 6A has a second recess 62. The second recess 62 is recessed from the outer peripheral surface 60 and the lower surface of the first pulley 6A and has a second surface 621 and a second guiding surface 622. The second surface 621 is a flat surface that is in surface contact with the abutting surface 921 of the second cover 92 described later. The second guiding surface 622 is a convex curved surface that is smoothly connected to both the outer peripheral surface 60 and the second surface 621 of the first pulley 6A.

[0045] The second component 82 is fixed to the third end portion 721 which is one end of the second steel strip 72 by appropriate means such as welding. A pair of through holes 821 are formed in the second component 82. In the third end portion 721, through holes are formed in a region corresponding to the pair of through holes 821. The through holes 821 are oblong holes with the vertical direction in Figure 5 the above as the long side direction. Threaded holes are formed in the second surface 621 of the first pulley 6A, and mounting bolts 86 are screwed into the threaded holes through the through holes 821. Thus, the second component 82 is fixed to the first pulley 6A. The second steel strip 72 wound around the first pulley 6A abuts against the outer peripheral surface 60, the second guide surface 622 and the second surface 621.

[0046] The second cover 92 is disposed in the second recess 62 and has a second outer peripheral surface 920, an abutting surface 921, a retracting surface 922, a recess 923 and working holes 924, 925. The abutting surface 921 is in surface contact with the second surface 621 of the first pulley 6A. The retracting surface 922 is a surface that retracts slightly to the Figure 5 right side of. The dimension by which the retracting surface 922 retracts from the abutting surface 921 is slightly larger than the thickness of the second steel strip 72. Thus, the portion of the second steel strip 72 located between the second surface 621 to the second guide surface 622 and the retracting surface 922 is slightly separated from the retracting surface 922. The recess 923 is a portion that is recessed to the Figure 5 right side in. The second component 82 is received in the recess 923. The working hole 924 is a through hole leading from the second outer peripheral surface 920 to the recess 923 and is used to operate the mounting bolt 86 from the outside with a tool. The working hole 925 is used to operate an adjusting screw 97 screwed into a threaded hole of the second cover 92 from the outside. When the adjusting screw 97 is screwed in, the second component 82 is pressed toward the circumferential direction of the first pulley 6A ( Figure 5 the upper side of), and the tension of the second steel strip 72 increases. By operating the adjusting screw 97 in this way, the tension of the second steel strip 72 can be adjusted. The working hole 925 and the adjusting screw 97 are an example of the belt tension adjusting portion of the present disclosure. Threaded holes extending along a direction orthogonal to the Figure 5 paper surface are formed in the second recess 62 of the first pulley 6A, and mounting bolts 96 are screwed into the threaded holes. Thus, the second cover 92 is fixed to the first pulley 6A so as to surround the second component 82.

[0047] The diameter of the second outer peripheral surface 920 of the second cover 92 is the same as the diameter of the outer peripheral surface 60 of the first pulley 6A. Here, "the second outer peripheral surface 920 and the outer peripheral surface 60 have the same diameter" means that the second outer peripheral surface 920 is an arc shape having the same radius of curvature as the radius of the outer peripheral surface 60. In a state where the second cover 92 is fixed to the first pulley 6A, the center of the radius of curvature of the second outer peripheral surface 920 coincides with the center of the outer peripheral surface 60, and the outer peripheral surface 60 and the second outer peripheral surface 920 form a series of circumferential shapes with the same diameter. In addition, in design, the second outer peripheral surface 920 and the outer peripheral surface 60 are set to have the same diameter, but in fact, some errors may occur in a state where the second cover 92 is fixed to the first pulley 6A.

[0048] As Figure 6 shown, the second pulley 6B has a third recess 63. The third recess 63 is recessed from the outer peripheral surface 60 and the upper surface of the second pulley 6B, and has a third surface 631 and a third guide surface 632. The third surface 631 is a plane that is in surface contact with the abutting surface 931 of the third cover 93 described later. The third guide surface 632 is a convex curved surface that is smoothly connected to both the outer peripheral surface 60 and the third surface 631 of the second pulley 6B.

[0049] The third block member 83 is fixed to the second end portion 712 which is the other end of the first steel belt 71 by appropriate means such as welding. A pair of through holes 831 are formed in the third block member 83. In the second end portion 712, through holes are formed in a region corresponding to the pair of through holes 831. A threaded hole is formed in the third surface 631 of the second pulley 6B, and the mounting bolt 86 is screwed into the threaded hole through the through holes 831. Thus, the third block member 83 is fixed to the second pulley 6B. The first steel belt 71 wound around the second pulley 6B abuts against the outer peripheral surface 60, the third guide surface 632, and the third surface 631.

[0050] The third cover 93 is disposed in the third recess 63, and has a third outer peripheral surface 930, an abutting surface 931, a retracted surface 932, a recess 933, and an operation hole 934. The abutting surface 931 is in surface contact with the third surface 631 of the second pulley 6B. The retracted surface 932 is a surface that retracts slightly to the Figure 6 left side of. The dimension by which the retracted surface 932 retracts from the abutting surface 931 is slightly larger than the thickness of the first steel belt 71. Thus, a portion of the first steel belt 71 located between the third surface 631 to the third guide surface 632 and the retracted surface 932 is slightly separated from the retracted surface 932.

[0051] The recess 933 is from the abutting surface 931 to Figure 6The left recessed part in [it], in which the third component 83 is received in the recess 933. The operation hole 934 is a through hole leading from the third outer peripheral surface 930 to the recess 933, and is used to operate the mounting bolt 86 from the outside through a tool. In the third recess 63 of the second pulley 6B, a threaded hole extending along a direction orthogonal to the paper surface of Figure 6 is formed, and the mounting bolt 96 is screwed into the threaded hole. Thus, the third cover 93 is fixed to the second pulley 6B so as to surround the third component 83.

[0052] The diameter of the third outer peripheral surface 930 of the third cover 93 is the same as the diameter of the outer peripheral surface 60 of the second pulley 6B. Here, "the third outer peripheral surface 930 and the outer peripheral surface 60 have the same diameter" means that the third outer peripheral surface 930 is an arc shape having the same radius of curvature as the radius of the outer peripheral surface 60. In the state where the third cover 93 is fixed to the second pulley 6B, the center of the radius of curvature of the third outer peripheral surface 930 coincides with the center of the outer peripheral surface 60, and the outer peripheral surface 60 and the third outer peripheral surface 930 form a series of circumferences of the same diameter. In addition, in design, the third outer peripheral surface 930 and the outer peripheral surface 60 are set to have the same diameter, but in fact, some errors may occur in the state where the third cover 93 is fixed to the second pulley 6B.

[0053] As Figure 7 shown, the second pulley 6B has a fourth recess 64. The fourth recess 64 is recessed from the outer peripheral surface 60 and the lower surface of the second pulley 6B, and has a fourth surface 641 and a fourth guide surface 642. The fourth surface 641 is a plane that is in surface contact with the abutting surface 941 of the fourth cover 94 described later. The fourth guide surface 642 is a convex curved surface that is smoothly connected to both the outer peripheral surface 60 and the fourth surface 641 of the second pulley 6B.

[0054] The fourth component 84 is fixed to the fourth end portion 722, which is the other end of the second steel belt 72, by appropriate means such as welding. A pair of through holes 841 are formed in the fourth component 84. In the fourth end portion 722, through holes are formed in a region corresponding to the pair of through holes 841. A threaded hole is formed in the fourth surface 641 of the second pulley 6B, and the mounting bolt 86 is screwed into the threaded hole through the through holes 841. Thus, the fourth component 84 is fixed to the second pulley 6B. The second steel belt 72 wound around the second pulley 6B abuts against the outer peripheral surface 60, the fourth guide surface 642, and the fourth surface 641.

[0055] The fourth cover 94 is disposed in the fourth recess 64, and has a fourth outer peripheral surface 940, an abutting surface 941, a retracted surface 942, a recess 943, and an operation hole 944. The abutting surface 941 is in surface contact with the fourth surface 641 of the second pulley 6B. The retracted surface 942 is slightly more Figure 7The surface that retracts downward. The dimension by which the retracting surface 942 retracts from the abutting surface 941 is slightly larger than the thickness of the second steel belt 72. Thus, the portion of the second steel belt 72 located between the fourth surface 641 to the fourth guiding surface 642 and the retracting surface 942 is slightly separated from the retracting surface 942. The recess 943 is the portion that is recessed downward from the abutting surface 941, and the fourth block member 84 is received in the recess 943. The working hole 944 is a through hole that leads from the fourth outer peripheral surface 940 to the recess 943 and is used to operate the mounting bolt 86 from the outside with a tool. In the fourth recess 64 of the second pulley 6B, a threaded hole is formed that extends along a direction orthogonal to the Figure 7 plane of the paper, and the mounting bolt 96 is screwed into the threaded hole. Thus, the fourth cover 94 is fixed to the second pulley 6B so as to surround the fourth block member 84. Figure 7 plane of the paper, and the mounting bolt 96 is screwed into the threaded hole. Thus, the fourth cover 94 is fixed to the second pulley 6B so as to surround the fourth block member 84.

[0056] The diameter of the fourth outer peripheral surface 940 of the fourth cover 94 is the same as the diameter of the outer peripheral surface 60 of the second pulley 6B. Here, "the fourth outer peripheral surface 940 and the outer peripheral surface 60 have the same diameter" means that the fourth outer peripheral surface 940 is an arc shape having the same radius of curvature as the radius of the outer peripheral surface 60. In the state where the fourth cover 94 is fixed to the second pulley 6B, the center of the radius of curvature of the fourth outer peripheral surface 940 coincides with the center of the outer peripheral surface 60, and the outer peripheral surface 60 and the fourth outer peripheral surface 940 form a series of circumferential shapes with the same diameter. In addition, in the design, the fourth outer peripheral surface 940 and the outer peripheral surface 60 are set to have the same diameter, but in fact, there may be some errors in the state where the fourth cover 94 is fixed to the second pulley 6B.

[0057] Figure 8 is a top view schematically showing the states of the first pulley 6A and the second pulley 6B rotating maximally in one rotational direction and rotating maximally in the other rotational direction. In addition, in Figure 8 , the second steel belt 72 is shown by a dashed line in order to distinguish it from the first steel belt 71.

[0058] As Figure 8 shown in (a) of

[0059] As Figure 8As shown in (b), in a state where the first pulley 6A and the second pulley 6B are rotated to the maximum extent in the other rotational direction, the first steel belt 71 is wound around the outer peripheral surface 60 of the second pulley 6B and the third outer peripheral surface 930 of the third cover 93, and is wound approximately once (about 360°) in the circumferential direction of the second pulley 6B. Further, the second steel belt 72 is wound around the outer peripheral surface 60 of the first pulley 6A and the second outer peripheral surface 920 of the second cover 92, and is wound approximately once (about 360°) in the circumferential direction of the first pulley 6A. From this, it can be seen that in the present embodiment, the rotational angles of the first pulley 6A and the second pulley 6B are approximately 360°.

[0060] Figure 2 The structures of the first pulley 6C and the second pulley 6D shown are the same as the structures of the above-mentioned first pulley 6A and second pulley 6B. The first steel belt 71 and the second steel belt 72 are also wound around the first pulley 6C and the second pulley 6D. The mounting structures of the first steel belt 71 and the second steel belt 72 with respect to these first pulley 6C and second pulley 6D are also the same as those of the above-mentioned first pulley 6A and second pulley 6B. The first steel belt 71 and the second steel belt 72 are fixed to the first pulley 6C and the second pulley 6D using the first block member 81 to the fourth block member 84. Further, the first cover 91 and the second cover 92 are mounted on the first pulley 6C in the same manner as on the first pulley 6A, and the third cover 93 and the fourth cover 94 are mounted on the second pulley 6D in the same manner as on the second pulley 6B. The rotational angles of the first pulley 6C and the second pulley 6D are approximately 360°, the same as those of the above-mentioned first pulley 6A and second pulley 6B.

[0061] Figure 2 The structures of the first pulley 6E and the second pulley 6F shown are the same as the structures of the above-mentioned first pulley 6A and second pulley 6B. The first steel belt 71 and the second steel belt 72 are also wound around the first pulley 6E and the first pulley 6E. The mounting structures of the first steel belt 71 and the second steel belt 72 with respect to these first pulley 6E and first pulley 6E are also the same as those of the above-mentioned first pulley 6A and second pulley 6B. The first steel belt 71 and the second steel belt 72 are fixed to the first pulley 6E and the second pulley 6F using the first block member 81 to the fourth block member 84. Further, the first cover 91 and the second cover 92 are mounted on the first pulley 6E in the same manner as on the first pulley 6A, and the third cover 93 and the fourth cover 94 are mounted on the second pulley 6F in the same manner as on the second pulley 6B. The rotational angles of the first pulley 6E and the second pulley 6F are approximately 360°, the same as those of the above-mentioned first pulley 6A and second pulley 6B.

[0062] Next, the operation of the present embodiment will be described.

[0063] In the transfer robot A1, a first steel belt 71 and a second steel belt 72 are wound around a first pulley 6A (6C, 6E) and a second pulley 6B (6D, 6F). The first steel belt 71 and the second steel belt 72 are end belts each having two end portions. The second steel belt 72 is disposed separately from the first steel belt 71 in the axial direction (vertical direction) of the first pulley 6A (6C, 6E) and the second pulley 6B (6D, 6F). The second steel belt 72 is wound around the first pulley 6A (6C, 6E) and the second pulley 6B (6D, 6F) in a direction opposite to the winding direction of the first steel belt 71.

[0064] The first pulleys 6A (6C, 6E) each have a first recess 61 and a second recess 62 recessed from the outer peripheral surface 60. A first block member 81 is fixed to a first end portion 711 which is one end of the first steel belt 71, and the first block member 81 is disposed in the first recess 61. A first cover 91 is fixedly disposed in the first recess 61 so as to surround the first block member 81. The first cover 91 has a first outer peripheral surface 910 having the same diameter as the outer peripheral surface 60 of the first pulley 6A (6C, 6E). A second block member 82 is fixed to a third end portion 721 which is one end of the second steel belt 72, and the second block member 82 is disposed in the second recess 62. A second cover 92 is fixedly disposed in the second recess 62 so as to surround the second block member 82. The second cover 92 has a second outer peripheral surface 920 having the same diameter as the outer peripheral surface 60 of the first pulley 6A (6C, 6E). With such a structure, the first steel belt 71 can be wound around the first outer peripheral surface 910 of the first cover 91 fixedly disposed to surround the first block member 81 without interfering with the first block member 81 which is the fixing portion of the first steel belt 71 with respect to the first pulley 6A (6C, 6E). In addition, the second steel belt 72 can be wound around the second outer peripheral surface 920 of the second cover 92 fixedly disposed to surround the second block member 82 without interfering with the second block member 82 which is the fixing portion of the second steel belt 72 with respect to the first pulley 6A (6C, 6E). Thereby, the first steel belt 71 (second steel belt 72) can cross the outer peripheral surface 60 of the first pulley 6A (6C, 6E) and the first outer peripheral surface 910 (second outer peripheral surface 920) of the first cover 91 (second cover 92), and can be wound approximately one week (about 360°) in the circumferential direction of the first pulley 6A (6C, 6E). Therefore, the rotation angle of the first pulley 6A (6C, 6E) can be enlarged.

[0065] The second pulleys 6B (6D, 6F) each have a third concave portion 63 and a fourth concave portion 64 that are recessed from the outer peripheral surface 60. A third block member 83 is fixed to the second end portion 712 that is the other end of the first steel belt 71, and the third block member 83 is disposed in the third concave portion 63. A third cover 93 is fixedly disposed in the third concave portion 63 so as to surround the third block member 83. The third cover 93 has a third outer peripheral surface 930 having the same diameter as the outer peripheral surface 60 of the second pulley 6B (6D, 6F). A fourth block member 84 is fixed to the fourth end portion 722 that is the other end of the second steel belt 72, and the fourth block member 84 is disposed in the fourth concave portion 64. A fourth cover 94 is fixedly disposed in the fourth concave portion 64 so as to surround the fourth block member 84. The fourth cover 94 has a fourth outer peripheral surface 940 having the same diameter as the outer peripheral surface 60 of the second pulley 6B (6D, 6F). With such a structure, the first steel belt 71 can be wound around the third outer peripheral surface 930 of the third cover 93 that is fixedly disposed to surround the third block member 83 without interfering with the third block member 83 that is the fixing portion of the first steel belt 71 with respect to the second pulley 6B (6D, 6F). In addition, the second steel belt 72 can be wound around the fourth outer peripheral surface 940 of the fourth cover 94 that is fixedly disposed to surround the fourth block member 84 without interfering with the fourth block member 84 that is the fixing portion of the second steel belt 72 with respect to the second pulley 6B (6D, 6F). Thereby, the first steel belt 71 (second steel belt 72) can cross the outer peripheral surface 60 of the second pulley 6B (6D, 6F) and the third outer peripheral surface 930 (fourth outer peripheral surface 940) of the third cover 93 (fourth cover 94) and be wound approximately one turn (about 360°) in the circumferential direction of the second pulley 6B (6D, 6F). In addition, as described above, the first steel belt 71 (second steel belt 72) can cross the outer peripheral surface 60 of the first pulley 6A (6C, 6E) and the first outer peripheral surface 910 (second outer peripheral surface 920) of the first cover 91 (second cover 92) and be wound approximately one turn (about 360°) in the circumferential direction of the first pulley 6A. Thereby, the rotation angles of the first pulley 6A and the second pulley 6B are about 360°. In the conventional structure (the structure described in Japanese Unexamined Patent Application Publication No. 2008-223974) Figure 3 the rotation angle of the pulley is, for example, about 300°. In the present embodiment, the rotation angles of the first pulley 6A (6C, 6E) and the second pulley 6B (6D, 6F) can be increased.

[0066] An adjustment screw 97 (belt tension adjustment portion) capable of pressing the first block member 81 in the circumferential direction toward the first pulley 6A (6C, 6E) is provided on the first cover 91. An adjustment screw 97 (belt tension adjustment portion) capable of pressing the second block member 82 in the circumferential direction toward the first pulley 6A (6C, 6E) is provided on the second cover 92. With such a structure, as Figure 2As shown, for example, when a plurality of first pulleys 6A, 6C are arranged in the direction of the first axis O1, the adjustment screw 97 can be easily operated from the outside, and the tensions of the first steel belt 71 and the second steel belt 72 can be easily adjusted. In addition, different from this embodiment, the adjustment screw 97 may be provided only on either the first cover 91 or the second cover 92. In this case, by operating the adjustment screw 97, the tensions of the first steel belt 71 and the second steel belt 72 mounted with opposite winding directions can also be adjusted.

[0067] The first concave portion 61 of the first pulley 6A (6C, 6E) has a first guide surface 612. The first guide surface 612 is smoothly connected to the outer peripheral surface 60 of the first pulley 6A and abuts against the first steel belt 71. In addition, the second concave portion 62 of the first pulley 6A (6C, 6E) has a second guide surface 622. The second guide surface 622 is smoothly connected to the outer peripheral surface 60 of the first pulley 6A and abuts against the second steel belt 72. According to such a structure, an eccentric load can be prevented from being generated on the first steel belt 71 and the second steel belt 72 wound around the first pulley 6A (6C, 6E), and the first pulley 6A (6C, 6E) can rotate smoothly. In the present embodiment, in the second pulley 6B (6D, 6F), third guide surfaces 632 and fourth guide surfaces 642 similar to the first guide surface 612 and the second guide surface 622 of the first pulley 6A (6C, 6E) are also formed. Thereby, an eccentric load can be prevented from being generated on the first steel belt 71 and the second steel belt 72 wound around the second pulley 6B (6D, 6F), and the second pulley 6B (6D, 6F) can rotate smoothly.

[0068] The belt transmission mechanism according to the present disclosure is not limited to the above-described embodiment. Various design changes can be made to the specific structure of the handling device according to the present disclosure.

[0069] -Symbol Explanation-

[0070] A1: Handling robot, 2: First arm, 3: Second arm, 6A, 6C, 6E: First pulley, 6B, 6D, 6F: Second pulley, 60: Outer peripheral surface, 61: First recess, 612: First guiding surface, 62: Second recess, 622: Second guiding surface, 63: Third recess, 64: Fourth recess, 71: First steel belt, 711: First end portion, 712: Second end portion, 72: Second steel belt, 721: Third end portion, 722: Fourth end portion, 81: First block member, 82: Second block member, 83: Third block member, 84: Fourth block member, 91: First cover, 910: First outer peripheral surface, 92: Second cover, 920: Second outer peripheral surface, 93: Third cover, 930: Third outer peripheral surface, 94: Fourth cover, 940: Fourth outer peripheral surface, 97: Adjusting screw (with tension adjusting portion), O1: First axis, O2: Second axis, O3: Third axis.

Claims

1. A belt transmission mechanism, comprising: The first pulley and the second pulley are configured to be rotatable around a pair of mutually parallel axes; A first steel belt having a first end portion mounted on the first pulley and a second end portion mounted on the second pulley, and wound around the first pulley and the second pulley; A second steel belt having a third end portion mounted on the first pulley and a fourth end portion mounted on the second pulley, and being separated from the first steel belt in the axial direction of the first pulley and the second pulley, and being wound around the first pulley and the second pulley in a direction opposite to that of the first steel belt; First hood; as well as The second cover, The first pulley has a first recess and a second recess respectively recessed from the outer peripheral surface. A first block member is fixed to the first end portion, and the first block member is disposed in the first recessed portion. The first cover is fixedly arranged in the first recess so as to surround the first block member and has a first outer peripheral surface having the same diameter as the outer peripheral surface of the first pulley. A second block member is fixed to the third end portion, and the second block member is disposed in the second recessed portion. The second cover is fixedly arranged in the second recessed portion so as to surround the second block member and has a second outer peripheral surface having the same diameter as the outer peripheral surface of the first pulley.

2. The belt transmission mechanism according to claim 1, wherein: The belt transmission mechanism further includes a third cover and a fourth cover. The second pulley has a third recess and a fourth recess respectively recessed from the outer peripheral surface. A third block member is fixed to the second end portion, and the third block member is disposed in the third recessed portion. The third cover is fixedly arranged in the third recessed portion so as to surround the third block member and has a third outer peripheral surface having the same diameter as the outer peripheral surface of the second pulley. A fourth block component is fixed to the fourth end portion, and the fourth block component is arranged in the fourth recessed portion. The fourth cover is fixedly arranged in the fourth recessed portion so as to surround the fourth block member and has a fourth outer peripheral surface having the same diameter as the outer peripheral surface of the second pulley.

3. The belt transmission mechanism according to claim 1, wherein: A belt tension adjusting portion capable of pressing the corresponding first block member or the second block member in the circumferential direction of the first pulley is provided on at least one of the first cover and the second cover.

4. The belt transmission mechanism according to claim 1, wherein: The first recess has a first guide surface that abuts against the first steel belt and smoothly connects to the outer peripheral surface of the first pulley. The second recess has a second guide surface that contacts the second steel belt and is smoothly connected to the outer peripheral surface of the first pulley.

5. A transport robot comprising: The belt transmission mechanism according to any one of claims 1 to 4; and a horizontal multi-joint arm mechanism having an arm that is rotated by the belt transmission mechanism.

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