JP6260137B2 - Industrial robot - Google Patents

Description

  The present invention relates to an industrial robot, and more particularly to an industrial robot that requires cable processing that does not hinder the turning operation of a turning portion.

  2. Description of the Related Art Conventionally, industrial robots equipped with a turning section that can be turned to exhibit a predetermined function have been put to practical use in various applications. Various cables such as motor power lines and encoder signal lines are arranged in the internal space of such industrial robots, and appropriate cable processing is performed so as not to hinder the turning operation. .

  As shown in FIG. 11, as an example of cable processing in the housing 103 that supports the swivel unit 100 so that the swivel unit 100 can swivel upward, the lower ends of the cables 104 are assembled to form the swivel unit 100 in the bottom wall of the housing 103. The maximum turning angle set in advance in either the forward or reverse direction by connecting the upper ends of the cables 104 together and fixing them at a portion spaced from the turning center C (indicated by a two-dot chain line) in FIG. When the turning unit 100 is in a neutral state and is connected to a portion separated from the turning center C of the turning unit 100 that is in a neutral state that can be turned up to, each cable straddles the turning center as viewed from the front in FIG. A cable process that is set to be in a (crossing) posture.

  With such cable processing, when the swivel unit 100 is swung in the forward direction or the reverse direction, as shown in FIG. 12, the upper end portion of each cable 104 moves with the swivel operation of the swivel unit 100, By changing the amount of twisting or bending of each cable 104 according to the amount of movement, the turning operation of the turning unit 100 within a predetermined angle range is not hindered.

  In addition, as disclosed in the following Patent Document 1, by placing the cable in a coiled state in a predetermined internal space and changing the twisting amount of the cable according to the turning angle of the turning portion, Cable processing is also known in which the turning operation of the turning part is not hindered.

JP 2003-170384 A

  By the way, when the former cable processing (the cable processing example shown in FIG. 11 and FIG. 12) is adopted, each cable has a posture that crosses the turning center when the turning portion is in a neutral state. Other parts and mechanisms cannot be arranged, and the space around the turning center becomes a dead space. Further, as in the cable processing shown in FIG. 11 and FIG. 12, if the upper end portion and the lower end portion of each cable are connected to a predetermined connection portion in a state where they are gathered together, It is considered that there is a relatively high possibility that a situation in which an excessive load concentrates on a specific cable or a situation in which cables in a twisted state interfere with each other occurs because the twist amount differs for each cable.

  Further, the above-described problems can occur when the cable processing shown in FIGS. 11 and 12 is adopted regardless of the type of cable.

  Note that the applicant assigns each cable between a parallel posture region that is parallel to one another on one horizontal plane, a vertical posture region that is parallel to one another on one vertical plane, and a parallel posture region and a vertical posture region. And an arcuate region that is bent in an arcuate shape, and a predetermined portion of the parallel posture region of each cable is secured by a common first clamp with a slight gap between adjacent cables. In addition, a patent application has been filed regarding a configuration in which a predetermined portion of each cable in a vertical posture region is held in a state where a slight gap is secured between adjacent cables by a common second clamp (Japanese Patent Laid-Open No. 2002). -011687). In such a configuration, when the swivel part to which the second clamp is fixed turns, only the second clamp turns and the first clamp remains fixed without moving, so that the second clamp turns. Accordingly, the arc-shaped region of each cable can be deformed to absorb the turning motion of the predetermined part.

  However, even in such a configuration, the horizontal posture region and the arc-shaped region of the cable are in a posture that crosses the turning center, and therefore other parts and mechanisms cannot be arranged at the turning center. It is difficult to make effective use of this space. Furthermore, since it is the structure which hold | maintains the cable arrange | positioned in parallel mutually with the clamp in the state which ensured some clearance gap, although possibility that a cable will interfere can be reduced, two orthogonally crossed mutually Since each cable is held by the first clamp and the second clamp on a plane (horizontal plane, vertical plane), when the turning portion turns, the cable is held by the portion held by the first clamp and the second clamp. The distance between the different parts differs for each cable, and the twist amount for each cable greatly varies as the turning angle increases. In this respect, it can be said that the configuration disclosed in Japanese Patent Laid-Open No. 20037-011687 has room for reconsideration.

  Further, the configuration disclosed in Patent Document 1 is considered to be suitable when there is a single cable, but when there are a plurality of cables, a coil shape is formed in a state in which the plurality of cables are bundled. It is difficult to make the cable itself, and interference between cables is likely to occur. In particular, in the configuration disclosed in Patent Document 1, in the case where the number of cables is large or in the case of a multi-core cable, the cable distance in the vertical direction is narrower toward the portion closer to the lower end of the cable due to the large weight. Therefore, there is a high possibility that the cables adjacent to each other in the upper and lower sides are in contact with each other and rubbed.

  The present invention has been made paying attention to such a problem, and a main purpose thereof is not to hinder the turning operation of the turning portion, and is dead at the turning center of the turning portion in the space in which the cable is arranged. An object of the present invention is to provide an industrial robot to which cable processing that can avoid the formation of a space and that can prevent and suppress interference between cables is provided.

That is, the present invention relates to an industrial robot including a fixed portion and a turning portion that can turn around a turning center axis with respect to the fixed portion, and is a first cable connecting portion that is relatively close to the turning portion. A movable end portion that is connected to the swivel portion and moves in accordance with the turning operation of the turning portion, and a fixed end portion that is connected to the second cable connection portion relatively far from the turning portion and does not move even if the turning portion turns. And a cable length from a movable end connection position that is a connection position of the movable end to the first cable connection section to a fixed end connection position that is a connection position of the fixed end to the second cable connection section. A plurality of cables set longer than the linear distance from the movable end connecting position to the fixed end connecting position along the turning center axis direction are arranged at equal or substantially equal intervals around the turning center axis. The movable end connection position and Cable bulge amount in which the area between the movable end connection position and the fixed end connection position of the cable bulges away from the turning center axis in the reference state where the fixed end connecting position faces the turning center axis direction Each cable can be transformed into a twisted state in which the amount of cable bulge is reduced with the amount of movement of the movable end of each cable that increases as the turning angle of the turning part increases from the reference state. When each cable is in the reference state, a predetermined structure is arranged in a space around the turning center axis surrounded by each cable and a specific area is inflated, and the turning part has a preset turning angle set in advance. when pivoted to, cases each cable of maximum twist state most twisted and arranged so as not to interfere with its structure, a plurality of cables, which are formed in the interior space of the fixing unit A motor that outputs a driving force for turning the swiveling part with respect to the fixed part is arranged outside the cable containing part and is not interfered with the inner wall of the cable containing part when it is housed in the cable housing part and in the reference state. It is characterized in that the.

  In the case of the industrial robot according to the present invention, the linear distance between the movable end connecting position and the fixed end connecting position of each cable along the turning center axis direction is determined from the movable end connecting position of the cable to the fixed end. Turn multiple cables set to be shorter than the length to the connection position (cable length from the movable end connection position to the fixed end connection position) and set to maximize the cable bulge amount in the reference state. By arranging them at equal or substantially equal intervals around the turning center axis of the part, there is a specific area around the turning center axis including the turning center axis surrounded by each cable in the reference state according to the amount of cable bulging. A space bulging in a direction away from the turning center axis than other regions (hereinafter referred to as “a space around the turning center”) can be formed. And in the industrial robot which concerns on this invention, the structure is arrange | positioned in this turning center periphery space. In other words, according to the industrial robot of the present invention, it is not possible to arrange the structure with conventional cable processing, and it is possible to arrange the structure in the space around the turning center that was a dead space. .

  Moreover, in the industrial robot according to the present invention, when the movable end of each cable moves around the turning center axis in accordance with the turning operation of the turning part, each cable arranged evenly or substantially equally around the turning center axis. By deforming the cable from the reference state to the twisted state, the cable that is in the maximum twisted state when the swivel portion is swung to a preset maximum swivel angle without any hindrance to the swivel operation of the swivel portion is structured. Since it is configured so as not to interfere with an object, the swollen portion in a specific area between the movable end connection position and the fixed end connection position of each cable is associated with the turning operation of the turning portion in the direction in which the turning angle increases. Even if the projecting amount gradually decreases, the arrangement condition of the structure disposed in the space around the turning center where the degree of bulging of the predetermined portion decreases according to the torsional deformation of each cable, for example, the turning angle of the turning portion Mechanism and configured to change in accordance with the deformation amount of the cable) in other words is not required, it is possible to effectively utilize if prior to turning around the center space was dead space as structure installation space.

  In particular, in the industrial robot according to the present invention, since a plurality of cables are arranged at equal or substantially equal intervals around the turning center axis, the movable ends and the fixed ends of each cable are assembled and connected. Compared with the mode in which the cables are twisted and arranged in a coiled state, the probability that adjacent cables around the turning center axis interfere with each other in both the reference state and the twisted state is drastically reduced. The probability that the cables interfere with each other can be made closer to zero as the number of cables is smaller or the distance between the cables around the turning center axis is larger. Of course, by employing the cable processing according to the present invention, it is possible to completely avoid a situation where the cables interfere with each other without depending on the number of cables and the distance between the cables around the turning center axis. In addition, by adopting cable processing in which a plurality of cables are arranged around the turning center axis at equal or substantially equal intervals, the twisting amount of each cable can be made uniform or substantially uniform between the cables with the turning operation of the turning part. As a result, it is possible to avoid a situation in which an excessive load acts on a specific cable. In addition, in the present invention, it is possible to effectively utilize the space around the turning center as a structure installation space by arranging a plurality of cables at equal or substantially equal intervals around the turning center axis. In the case where the configuration disclosed in Patent Document 1 causes a problem, that is, in the case of a large number of cables or a multi-core cable, due to the large weight, the portion closer to the lower end of the cable is closer to the vertical direction. This is advantageous in this respect because the distance between the cables becomes narrow, and the cables adjacent to each other in the upper and lower sides cannot come into contact with each other and rub against each other.

  Further, in the case of the industrial robot according to the present invention, each cable having the maximum bulge amount from the turning center axis in a state where the turning portion is not turning has a movable end connecting position and a fixed end connecting position. Compared with the mode in which the load due to torsional deformation continues to be applied (the mode in which each cable is arranged in a coiled state, etc.) because it is not twisted in the reference state facing the swivel axis. By limiting the time for receiving the load caused by the deformation only when the swivel part swivels, it is possible to make it difficult to be affected by the torsional deformation, contributing to the extension of the life of each cable.

  In the present invention, the cable in the reference state in which the bulge amount of the region between the movable end connection position and the fixed end connection position of the cable is the maximum is not twisted when captured in units of cables. However, it is not intended to positively exclude from the scope of the present invention an embodiment that is twisted by an arbitrary amount (regardless of whether it is a minute amount) in the reference state.

  The reference state of the cable in the present invention is a state in which the movable end connection position and the fixed end connection position face the turning center axis direction, and the movable end connection position and the fixed end connection position are the turning center. Of course, “facing directly in front when viewed from the direction parallel to the axis”, “the movable end connection position and the fixed end connection position are not directly in front when viewed from the direction parallel to the rotation center axis, but in the direction of the rotation center axis. It also includes the state of “facing at an arbitrary angle with respect to”. In the latter case, that is, the state that “the movable end connecting position and the fixed end connecting position face each other at an arbitrary angle with respect to the turning center axis direction although they are not directly in front when viewed from the direction parallel to the turning center axis” This is a state that occurs when the distance from the movable end connecting position to the turning central axis and the distance from the fixed end connecting position to the turning central axis are different from each other when captured in units of cables.

  By the way, when adopting a mode in which the distance from the movable end connecting position to the turning central axis and the distance from the fixed end connecting position to the turning central axis are adopted, it is possible to move adjacent to the turning central axis. The interval between the end connection positions and the interval between the fixed end connection positions adjacent to each other around the turning center axis are also greatly different. In other words, the pitch (separation distance) around the turning center axis of the connecting positions having the shorter distance to the turning center axis in the movable end connecting position or the fixed end connecting position has the longer distance to the turning center axis. It becomes shorter than the pitch around the turning center axis between the connection positions. This is combined with the fact that when each cable is deformed from the standard state to the twisted state, the amount of twist deformation of the movable end side region of each cable and the amount of twist deformation of the fixed end side region are greatly different. Of these cables, the region near the connection position with the shorter distance to the turning center axis interferes with the same area of the adjacent cable around the turning center axis, or the situation is too close without interference. it is conceivable that.

  Therefore, in the industrial robot of the present invention, the movable end connection positions of the cables are arranged at an equal pitch on the circumference centered on the rotation center axis, and the movable end connection of each cable is centered on the rotation center axis. The fixed end connection positions of the cables are preferably set to be arranged at an equal pitch on the circumference having the same or substantially the same radius as the circumference arranged at an equal pitch. By adopting such cable processing, it is possible to prevent / suppress the phenomenon that the torsional deformation amount of each cable is greatly different between the movable end side region and the fixed end side region. Interference between adjacent cables can be avoided.

In the present invention, the structure disposed in the space around the turning center is not particularly limited. However, when the industrial robot of the present invention is configured so that the turning part can be raised and lowered, the turning part can be raised and lowered. The components of the lifting mechanism to be moved can be employed as a structure arranged in the space around the turning center. In this case, it is preferable that a driving motor serving as a driving source for the lifting mechanism is disposed outside the cable housing portion.

Further, the present invention relates to an industrial robot used in various fields. As a preferred example of the industrial robot, a hand capable of moving forward and backward along a predetermined forward / backward direction is provided at the tip, and at least a base is used. A transfer robot for transferring a semiconductor wafer that includes an arm whose end is turnable around a turning center axis and that is disposed in the wafer transfer chamber and delivers the semiconductor wafer can be given.

  According to the present invention, a plurality of cables having the maximum bulge amount with respect to the turning center axis in the reference state are arranged evenly or substantially uniformly around the turning stop axis, and the space around the turning center surrounded by the plurality of cables is arranged. Since the structure can be arranged and set so that it does not interfere with the structure even when the cables are twisted in accordance with the turning movement of the turning section, it may interfere with the turning action of the turning section. In addition, it is possible to avoid the formation of a dead space at the turning center of the turning portion in the space in which the cable is arranged, and it is possible to prevent / suppress interference between the cables.

1 is an overall schematic diagram of a transfer robot according to an embodiment of the present invention. FIG. 2 is a diagram corresponding to FIG. 1 of the transfer robot in which the hand is in a delivery position in the embodiment. The figure which shows the structure which has arrange | positioned each cable of a reference | standard state in the housing | casing in the transfer robot which concerns on the same embodiment. The figure which shows the principal part of FIG. The figure which looked at the principal part of FIG. 3 from the direction orthogonal to the turning center axis. Xx sectional view taken on the line of FIG. FIG. 5 is a sectional view taken along line yy of FIG. 4. FIG. 4 is a view corresponding to FIG. 3 in a state in which the turning unit is moved upward in the transfer robot according to the embodiment. FIG. 5 is a diagram corresponding to FIG. 4 in which each cable in the housing is in a maximum twisted state in the same embodiment. FIG. 6 is a diagram corresponding to FIG. 5 in which each cable in the housing is in a maximum twisted state in the embodiment. The figure which shows an example of the conventional cable process. FIG. 11 is a diagram corresponding to FIG. 11, showing a state in which the turning unit has turned a predetermined angle in a configuration employing conventional cable processing.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  In this embodiment, as shown in FIGS. 1 and 2, the industrial robot is provided with a hand 11 capable of moving back and forth in a predetermined advancing and retracting direction at the distal end, and at least a base end configured to be turnable. The case of the transfer robot T having 12 will be described.

  The transfer robot T moves the hand 11 provided at the tip along a linear movement path between the transfer start position (S) shown in FIG. 1 and the delivery position (E) shown in FIG. A transfer drive mechanism 1 having a movable arm 12 and a main body 13 that rotatably supports the base end portion of the arm 12, and the hand 11 is moved from a transfer start position (S) to a delivery position (by a linear operation and a swing operation). E), the transfer object W on the hand 11 can be transferred to a predetermined transfer destination position. Examples of the transfer object include a disk-shaped semiconductor wafer W and a liquid crystal panel (not shown).

  As shown in FIGS. 1 and 2, the transfer robot T of the present embodiment is disposed in the wafer transfer chamber A, and delivers the wafer W to the port B1 in the load lock chamber B adjacent to the wafer transfer chamber A. Alternatively, the wafer W can be delivered into a wafer storage container on a load port (not shown) adjacent to the wafer transfer chamber A. 1 and 2 exemplify a configuration in which one load lock chamber B is adjacent to the wafer transfer chamber A, but a plurality of load lock chambers B are adjacent to the wafer transfer chamber A. The wafer W may be transferred to the port B1 in B.

  As shown in FIGS. 1 and 2, the arm 12 constituting the transport driving mechanism 1 includes a first link element 14 disposed on the most proximal side (main body 13 side) of the arm 12, and a first link element 14. The second link element 15 is connected to the front end of the second link element 15 so as to be horizontally turnable, and the hand 11 is an end effector connected to the front end of the second link element 15 so as to be horizontally turnable. The arm 12 has a link structure (multiple shapes) whose shape changes between a folded state (see FIG. 1) in which the arm length is minimum and an extended state (see FIG. 2) in which the arm length is longer than in the folded state. Joint structure). Further, in the internal space of the first link element 14, a power transmission mechanism (for example, a pulley and a belt) that transmits power to the second link element 15 to rotate the second link element 15 is provided. A power transmission mechanism (for example, a pulley and a belt) that transmits power to the hand 11 to rotate the hand 11 is also provided in the internal space (not shown). Although FIG. 1 shows a hand 11 that is formed in a fork shape with a bifurcated tip, for example, a hand 11 having another shape such as a tip that is formed in a substantially rectangular shape in plan view is applied. May be.

  In such an arm 12, the base 11 is horizontally swiveled around the turning center axis C, or the link elements 14 and 15 are horizontally swiveled at the joint portion to appropriately deform the shape of the entire arm 12, while the hand 11 is moved. The wafer W is moved from the transfer start position (S) to the delivery position (E) to transfer the wafer W to a predetermined transfer target position (regular transfer position). It is to be noted that a plurality of arms 12 are provided in the height direction, or a plurality of sets of transfer robots are provided in the same horizontal plane, and different movements are performed for each arm 12 or the same movement is performed to improve transfer efficiency and processing efficiency. Improvements can also be made.

  The transport robot T according to the present embodiment controls the operation of the transport drive mechanism 1 by the control unit 2. 1 and 2 exemplify a mode in which the control unit 2 is built in or attached to the main body unit 13, the control unit is connected to the main body unit 13 by connecting an information processing device or the like separate from the main unit 13. 2 can also be configured.

  As shown in FIGS. 3 to 5, the main body 13 of the transfer robot T according to the present embodiment includes a fixed portion 3 and a turning portion 4 that can turn with respect to the fixed portion 3. In the present embodiment, the swivel unit 4 is disposed above the fixed unit 3. FIG. 3 is a cross-sectional view showing the internal structure of the transfer robot T, but for convenience of explanation, the parallel oblique lines attached to the cut surface are omitted.

  The fixing portion 3 has an internal space 3S surrounded by the side wall 31, the upper wall 32, and the bottom wall 33. In the internal space 3S, a cable housing portion 5 capable of housing a plurality of cables 9, and a cable housing portion 5 An elevating mechanism 6 that moves the hoist so as to move up and down is disposed.

  The cable housing portion 5 has a cable housing space 5S surrounded by the side wall 51, the upper wall 52, and the bottom wall 53, and the first cable connecting portion 7 provided in a portion near the upper wall 52 in the cable housing space 5S. And a second cable connection portion 8 provided in a portion close to the bottom wall 53 in the cable housing space 5S. In the present embodiment, the entire cable 9 is not arranged in the cable housing space 5S, but the upper end side portion including the upper end portion of each cable 9 is arranged in the internal space 4S of the swivel unit 4. The lower end portion side portion including the lower end portion is passed through a cable guide 34 provided in a predetermined position (in the illustrated example, near the lower end portion of the cable housing portion 5) in the internal space 3S of the fixed portion 3 and outside the cable housing space 5S. It is pulled out of the cable housing space 5S. Here, of each cable 9 housed in the cable housing portion 5, a portion connected to the first cable connection portion 7 is referred to as a “movable end portion”, and a portion connected to the second cable connection portion 8 is referred to as a “fixed end”. Part ". One end of the cable guide 34 is attached to the side wall 51 of the cable housing portion 5, and the other end is supported by a cable guide support portion 35 disposed in a standing posture on the bottom wall 33 of the fixed portion 3. In the present embodiment, a side opening (not shown) that connects the cable housing space 5S to the internal space 3S of the fixed portion 3 is formed in the side wall 51 of the cable housing portion 5 near the mounting position of the cable guide 34. The lower end side portion of each cable 9 pulled out from the cable housing space 5S through the side opening is passed through the cable guide 34.

  The first cable connection portion 7 has a cylindrical shape centered on the turning center C of the turning portion 4, and is as shown in FIGS. 3 and 6 (FIG. 6 is a sectional view taken along line xx of FIG. 5). The first cable insertion holding portions 71 that can insert the movable end portions of the respective cables 9 and can hold the inserted movable end portions are provided at equal pitches in the circumferential direction on the inward surface (inner peripheral surface). A first cable connection tubular body 72 is provided. The plurality of first cable insertion holding portions 71 are arranged on the circumference of the same radius centered on the turning center C of the turning portion 4, and the interval between the first cable insertion holding portions 71 adjacent in the circumferential direction is substantially the same. Will be equal. Here, instead of “the interval between the first cable insertion holding portions 71 adjacent in the circumferential direction becomes equal”, “the interval between the first cable insertion holding portions 71 adjacent in the circumferential direction becomes substantially equal” This is because the angle of 360 degrees for one round is not evenly divisible by the number of first cable insertion holding portions 71 (“7” in the illustrated example).

  The first cable insertion holding portion 71 has a first opening 73 that penetrates in the height direction and is opened outward when viewed from the center of the first cable connection cylindrical body 72. The movable end portion of each cable 9 inserted into the first opening 73 that penetrates only in the height direction while being attached to the inner peripheral surface of the body 72 is held. In the present embodiment, the first cable connected to the first cable connection tubular body 72 by the bolt 74 that can be screwed into the first cable insertion holding portion 71 from the outward surface (outer peripheral surface) of the first cable connection tubular body 72. It is configured so that a good mounting state of the insertion holding portion 71 and a good holding state (tightened state) of the first cable insertion holding portion 71 with respect to the movable end portion of the cable 9 can be maintained (see FIG. 6).

  In the transfer robot T of this embodiment, the movable end portions of the cables 9 accommodated in the cable accommodating portion 5 are inserted and held in the first cable insertion holding portions 71 provided in total in the first cable connecting portion 7. Can be made. Therefore, the “movable end connection position 91 that is the connection position of the movable end with respect to the first cable connection portion 7” in the present invention (this embodiment) is defined by the position of each first cable insertion holding portion 71. It can be said.

  The first cable connection portion 7 of the present embodiment is a first cable connection tubular body 72 having a cable insertion space 7S penetrating in the height direction, and the first cable insertion holding portion 71 at the lower end portion on the inward surface. The lower cylindrical portion 75 provided with the upper cylindrical portion 77 disposed above the lower cylindrical portion 75 via the stepped portion 76, and the flange provided on the upper end portion of the upper cylindrical portion 77. It is comprised by the part 78. The cable insertion space 7 </ b> S communicates with the internal space 4 </ b> S of the turning portion 4 at the upper end portion of the first cable connection tubular body 72, and the cable accommodation space 5 </ b> S of the cable accommodation portion 5 at the lower end portion of the first cable connection tubular body 72. Communicating with The radial space in the cable insertion space 7 </ b> S is set so that the upper cylindrical body 77 is narrower than the lower cylindrical body 75, and the lower cylindrical body 75 of each cable 9 is provided. Predetermined regions above the portion held by the first cable insertion holding portion 71 are in contact with or close to each other in the internal space of the upper cylindrical body 77 (see FIG. 6). Further, the first cable connecting tubular body 72 of the present embodiment integrally forms the lower tubular portion 75, the step portion 76, the upper tubular portion 77, and the flange portion 78. In the present embodiment, the first cable connecting tubular body 72 is held by the first holding portion 42 disposed in the internal space 4S of the turning portion 4 so that the first cable connecting tubular body 72 rotates integrally with the turning portion 4. (See FIG. 3).

  Of each cable 9, the upper end side portion from the movable end portion held by each first cable insertion holding portion 71 is inside the turning portion 4 via the cable insertion space 7 </ b> S of the first cable connection tubular body 72. Arranged in the space 4S. Appropriate connection terminals are provided at the ends of the cables 9 arranged in the internal space 4S of the swivel unit 4, and each connection terminal is connected to each motor M or encoder (not shown) in the internal space 4S of the swivel unit 4. Connected. FIG. 3 illustrates two motors M in the internal space of the turning unit 4 and a cable 9 that is a power line of each motor M. Of these two motors M, the motor M on the right side relative to the paper surface outputs a driving force for turning the turning portion 4 relative to the fixed portion 3, and the motor on the left side relatively toward the paper surface. M outputs a driving force for moving the hand 11 of the arm 12 forward and backward.

  Then, in a state where the movable end portion of each cable 9 is inserted and held in each first cable insertion holding portion 71, when the turning portion 4 turns with respect to the fixed portion 3, the movable end portion of each cable 9 is It moves in the circumferential direction while maintaining the holding state by each first cable insertion holding portion 71.

  Further, the transfer robot T of the present embodiment has the fixed end of each cable 9 positioned farther from the motor M than the first cable connection 7 in the housing 3 (in the present embodiment, the first cable connection 7). 2nd cable connection part 8 provided in the lower position).

  As shown in FIG. 7 (the figure is a cross-sectional view taken along the line yy of FIG. 5), the second cable connection portion 8 has an inward surface set in a circular shape in plan view and an outward surface in a polygonal shape in plan view. A plurality of insertion recesses 82, each of which has an annular body 81 set as a shape, into which a fixed end of each cable 9 can be inserted, are formed in a flat flat portion on the outward surface of the annular body 81, and each insertion recess A pressing fixing portion 83 that can fix the cable 9 inserted into the cable 82 from the outward surface side of the annular body 81 and fix the cable 9 so as not to be removed is provided. In the present embodiment, the combination of the insertion concave portion 82 and the pressing fixing portion 83 includes the second cable insertion holding portion 84 that can insert the fixed end portion of each cable 9 and can hold the inserted fixed end portion. It is composed. The center of the annular body 81 and the center of the first cable connecting tubular body 72 are both coincident or substantially coincident with the turning center C of the turning portion 4. In the present embodiment, the annular cable 81 is held by the second holding portion 54 provided on the bottom wall 53 of the cable housing portion 5, and the position of the second cable insertion holding portion 84 is maintained even when the turning portion 4 is turned. It is configured not to move (see FIG. 3). In the present embodiment, the bolt 85 inserted into the pressing and fixing portion 83 is screwed into the annular body 81, so that a good mounting state of the pressing and fixing portion 83 with respect to the annular body 81 and the second end with respect to the fixed end of the cable 9 are achieved. The cable insertion holding portion 84 is configured to maintain a good holding state (tightened state) (see FIG. 7).

  Each cable 9 is fixed even if the turning part 4 turns with respect to the fixing part 3 in a state where the fixed end part of each cable 9 is inserted and held in each second cable insertion holding part 84 having such a configuration. The end portion remains in the position while maintaining the holding state by the second cable insertion holding portions 84 and does not move in the circumferential direction.

  In the transfer robot T of the present embodiment, as shown in FIG. 7, a plurality of second cable insertion holding portions 84 are provided so as to be arranged on the circumference of the same radius centered on the turning center C of the turning portion 4. The intervals between the second cable insertion holding portions 84 adjacent in the circumferential direction are set to be substantially equal. In the present embodiment, similarly to the first cable insertion holding portion 71, the angle of 360 degrees for one round is not evenly divisible by the number of second cable insertion holding portions 84 (seven in the illustrated example). The interval between the second cable insertion holding portions 84 adjacent to each other in the circumferential direction is “substantially the same”.

  In the transfer robot T of the present embodiment, the fixed end portions of the cables 9 can be inserted and held in the second cable insertion holding portions 84 provided in total in the second cable connection portion 8. Therefore, the “fixed end connection position 92 that is the connection position of the fixed end with respect to the second cable connection portion 8” in the present invention (this embodiment) is defined by the position of each second cable insertion holding portion 84. It can be said.

In the transfer robot T according to the present embodiment, the fixed end position is connected to the second cable connecting portion 8 from the movable end connecting position 91 that is the connecting position of the movable end portion to the first cable connecting portion 7. A plurality of cables 9 in which the cable length to the end connection position 92 is set to be longer than the linear distance from the movable end connection position 91 to the fixed end connection position 92 along the turning center axis C direction The cable housing space 5S is arranged at equal or substantially equal intervals around the turning center axis C. Therefore, as shown in FIGS. 4 and 5, the movable end connection position 91 and the fixed end connection position 92 of each cable 9 are movable in the cable 9 in a state where they face each other substantially in front of the turning center axis C. cable inflated amount that bulges in a direction away from the pivot axis C in the region between the end connection position 91 and the fixed end connection position 92 is maximized. When this state is the reference state of the cable 9, in the reference state, the portion farther from the movable end connection position 91 and the fixed end connection position 92, that is, the middle between the movable end connection position 91 and the fixed end connection position 92. The closer to, the greater the amount of cable bulge. In the surrounding space including the turning center C surrounded by the cable 9 in such a reference state (hereinafter referred to as “turning center surrounding space 9S”), the central portion in the direction of the turning center axis C is separated from the turning center axis C. In this embodiment, a structure is arranged in the space 9S around the turning center.

  In the transfer robot T according to the present embodiment, a ball screw 61 that is a component of the elevating mechanism 6 that moves the cable housing portion 5 to be movable up and down, and a ball screw cover 62 that covers the ball screw 61 are arranged in the space 9S around the turning center. (The ball screw cover 62 is omitted in FIG. 3, and the ball screw 61 is omitted in FIG. 7). Further, when a nut 63 that can be screwed back and forth with respect to the ball screw 61 is fixed to the bottom wall 53 of the cable housing portion 5 and the ball screw driving motor 6M disposed near the bottom wall 33 of the fixing portion 3 is driven. Depending on the rotation angle of the ball screw 61 and the rotation direction of the ball screw 61, the nut 63, and thus the entire cable housing portion 5, can be moved up and down in the axial direction of the ball screw 61 (see FIGS. 3 and 8). Note that the axis center of the ball screw 61 coincides with or substantially coincides with the turning center C of the turning portion 4. Further, in the present embodiment, the guide slider 63 that guides the up-and-down movement of the cable housing portion 5 is supported by the slider support portion 36 provided on the side wall 31 of the fixed portion 3 so as to be slidable. The ball screw cover 62 can cover the ball screw 61 without impairing the function of the ball screw 61. The ball screw cover 62 is disposed in the turning center peripheral space 9S in a fixed state that does not move relative to the housing 3 in the height direction when the ball screw 61 is operated. In the present embodiment, a cylindrical screw with a sharpened tip (upper end) is applied as the ball screw cover 62. When the cable housing part 5 is lifted and lowered by the lifting mechanism 6, the turning part 4 and the arm 12 are also lifted and lowered together with the cable housing part 5.

  As shown in FIGS. 3 and 8, the turning portion 4 is supported by the fixed portion 3 by a bearing portion 41 so as to be turnable. In the present embodiment, the bearing portion 41 is attached in a state in which the inward surface of the bearing portion 41 faces the outward surface of the upper tubular portion 77 of the first cable connection tubular body 72 so as to be in contact therewith. In addition to the motor M and the first holding part 42 described above, the internal space 4S of the turning part 4 includes a reduction gear G and a motor M that outputs a driving force for turning the entire turning part 4 and the reduction gear G. And a turning driving force transmission belt G1 interposed therebetween. Such a turning part 4 can turn with respect to the fixed part 3 and moves up and down simultaneously with the cable housing part 5 according to the operation amount of the ball screw 61 (the amount of rotation and the direction of rotation of the screw shaft).

  In the present embodiment, at least a portion between the movable end portion and the fixed end portion is provided in association with each motor M in addition to the power line of the motor M in the cable 9 that is accommodated in the cable accommodating portion 5. Various cables 9 such as a signal line of an encoder (not shown) are included. Of each cable 9. The “cable 9” in the following description means a cable 9 generically referring to power lines and signal lines housed and arranged in the cable housing part 5 unless otherwise specified.

The transfer robot T according to the present embodiment is configured so that the turning unit 4 can turn both in the forward and reverse directions, with the turning angle when the cable 9 is in the above-described reference state as a reference (reference angle). ing. In this embodiment, for example, when the turning unit 4 is set to be capable of turning up to 141 degrees in the forward and reverse directions with respect to the reference angle, and the maximum angle turn in the reverse direction from the position of the maximum turn in the forward direction, The turning angle is set to be 282 degrees. Here, the turning angle of the turning unit 4 in the forward / reverse direction is based on the following formula 1 when the number of transfer destinations (load lock chamber B, etc.) of the wafer W by the transfer robot T is n, for example. Can be set.
(N-1) / n × 1/2 × 360 + α (Formula 1)
Α in the above equation 1 corresponds to the play angle, and can be set to an appropriate value depending on the specifications.

  When the turning part 4 turns in either the forward or reverse direction from the reference angle, the first cable connection part 7 also turns in the same direction as the turning part 4. As a result, the movable end portion (movable end connection position 91) of each cable 9 moves around the turning center axis C. At this time, since the fixed end (fixed end connection position 92) of each cable 9 does not move, each cable 9 is twisted according to the movement of the movable end connection position 91, and the movable end connection position is reached. The amount of cable bulge in the portion between 91 and the fixed end connection position 92 is smaller than that in the reference state. When the turning unit 4 is turned to a preset maximum turning angle, the moving amount of the movable end of each cable 9 is also maximized, and the cable bulge amount is minimized as shown in FIGS. Each of the cables 9 that have become the maximum twisted state is the most twisted within the assumed range.

  In the transfer robot T of the present embodiment, even when the cables 9 not interfering with each other in the reference state are in the maximum twisted state, they do not interfere with each other, and the combination of the plurality of cables 9 in the maximum twisted state It is set to form a substantially cylindrical solid object as a whole. Further, the turning center peripheral space 9S surrounded by the cables 9 in the maximum twisted state is a hollow, substantially cylindrical space having almost no bulge in the central portion in the turning center axis C direction. That is, the space shape of the turning center peripheral space 9 </ b> S changes according to the twist deformation of the cable 9.

  Even if the transfer robot T of this embodiment arrange | positions the ball screw 61 and the ball screw cover 62 in the rotation center periphery space 9S, and each cable 9 will be in the maximum twist state with the turning operation | movement of the turning part 4. Each cable 9 is configured not to interfere with the ball screw 61 and the ball screw cover 62. Here, the width (squeezing degree) of the space 9S around the turning center when the rotation motor M is turned to the maximum turning angle is the amount of bulging of the cable 9 in the maximum twisted state, in other words, from the cable 9 to the turning center. It is defined by the distance (radius) to the axis C. In the present embodiment, the cable 9 in the maximum twist state is set so that the distance to the turning center axis C is substantially the same over the entire range from the movable end connection position 91 to the fixed end connection position 92. Of the structures (the ball screw 61 and the ball screw cover 62 in the present embodiment) arranged in the space 9S around the turning center, the distance to the turning center axis C is closest to the cable 9 in the radial direction around the turning center axis C. Each cable 9 is configured not to interfere with the ball screw 61 and the ball screw cover 62 by setting the distance from the arrangement position of the structure (the ball screw cover 62 in this embodiment) to the turning center axis C.

  Further, in the transfer robot T according to the present embodiment, the portion of the cable 9 that is in the reference state where the expansion amount of the cable 9 is the maximum and that is farthest from the turning center axis C does not interfere with the side wall 51 of the cable housing portion 5. It is set.

  As described above, the transfer robot T according to the present embodiment has the movable end connection position 91 and the fixed end connection position 92 of each cable 9 facing each other in the direction of the turning axis C when each cable 9 is in the reference state. Are set to be shorter than the cable length from the movable end connection position 91 to the fixed end connection position 92 of the cable 9 so that the cable bulge amount is maximized in the reference state. Are arranged at equal or substantially equal intervals around the turning center axis C of the turning unit 4, so that the turning center axis peripheral space S including the turning center axis C surrounded by each cable 9 in the reference state is provided. A space in which the central portion in the direction of the turning central axis C is bulged can be formed. The width of the turning center peripheral space 9S is changed by the torsional deformation of the cable 9 that is twisted more as the moving distance of the movable end connecting position 91 that moves around the turning center axis C is longer according to the turning angle of the turning portion 4. In the transfer robot T according to the present embodiment, when the turning portion turns to the maximum turning angle, the turning center is turned by the cable 9 in the maximum twist state that minimizes the amount of cable bulging. By setting so that the surrounding space 9S is not squeezed, the structure cannot be placed with conventional cable processing, and the structure is placed in the turning center surrounding space 9S that has become a dead space. can do.

  Furthermore, since the transfer robot T according to the present embodiment arranges the plurality of cables 9 around the turning center axis C at equal or substantially equal intervals, the movable ends and the fixed ends of the cables 9 are arranged with each other. A mode in which the cables are assembled and connected, a mode in which each cable 9 is twisted in a coiled state, or two planes (horizontal plane, vertical plane) orthogonal to each other, each cable being a first clamp and a second clamp Compared with the mode held by the above, the distance between the movable ends of the adjacent cables 9 and the distance between the fixed ends of the adjacent cables 9 are different even when each cable is twisted with the turning operation of the turning portion 4. In any case, the distance between the movable end connection position 91 and the fixed end connection position 92 is different for each cable 9 without any change from the respective intervals in the state before twisting (reference state). Of course, the amount of twist of each cable 9 can be made uniform or substantially uniform for all the cables 9, and it is possible to avoid a situation in which an excessive load concentrates on the specific cable 9 and acts on the cable 9. Even in the case of a large number of cables or multi-core cables, it is not necessary to arrange each cable 9 in a coiled state. There is no possibility that the cables become narrow and come into contact with each other and rub against each other, and the probability that adjacent cables 9 around the turning center axis C interfere with each other in both the reference state and the twisted state (including the maximum twisted state). Can be reduced, and suitable cable processing can be realized.

  In particular, each cable 9 having the maximum bulge amount when the swivel unit 4 is not swiveling has the movable end connection position 91 and the fixed end connection position 92 substantially in front of the swivel axis C in this reference state. Since it is in a state where it is not twisted facing each other, the load due to torsional deformation is constantly applied to the cable 9 as compared to the state in which the load due to torsional deformation always continues (such as an aspect in which each cable 9 is twisted in a coil shape). The operating time can be limited during the turning operation of the turning unit 4, which contributes to the extension of the service life of each cable 9.

  Further, in the transfer robot T according to the present embodiment, the movable end connection positions 91 of the cables 9 are arranged on the circumference around the turning center axis C at an equal pitch, and the cables 9 are centered on the turning center axis C and are connected to each cable. Nine movable end connection positions 91 are set so that the fixed end connection positions 92 of each cable 9 are arranged at an equal pitch on the circumference having substantially the same radius as the circumference arranged at an equal pitch. Here, for example, if the difference between the distance from the movable end connecting position 91 to the turning center axis C and the distance from the fixed end connecting position 92 to the turning center axis C is set large, the movable end of each cable 9 is set. The pitch between the connection positions 91 and the pitch between the fixed end connection positions 92 are also greatly different from each other, and when each cable 9 is deformed from the reference state to the twisted state in such an aspect, the movable end portion of each cable 9 is The torsional deformation amount of the side region is different from the torsional deformation amount of the fixed end side region, and among the cables 9, the region near the connection position where the distance to the turning center axis C is shorter is adjacent to the turning center axis C. It is assumed that a situation occurs in which the same region of the matching cable 9 is interfered with or is not too close. However, in the transfer robot T according to the present embodiment, the movable end connection position 91 and the fixed end connection position 92 of each cable 9 are both equidistant on the circumference of the substantially same radius centered on the turning center axis C. Since they are set so as to be lined up, the amount of twist deformation in each cable 9 is not greatly different between the movable end side region and the fixed end side region, and the cables adjacent to the periphery of the turning center axis C even in the maximum twist state. Interference between the nine can be avoided.

  In addition, this invention is not limited to embodiment mentioned above. For example, the structure arranged in the peripheral space including the turning center surrounded by a plurality of cables is not limited to the components constituting the lifting mechanism, and an appropriate structure can be selected according to the application, specifications, and the like.

  Moreover, the industrial robot to which the above-described cable processing is applied may be an industrial robot other than the transfer robot (such as various industrial robots having a turning axis).

  The number of cables is not particularly limited as long as it is plural, and the type of cable is also not particularly limited. In addition to power lines such as power cables and various signal lines, soft tubes used for air piping, etc. The cable processing (cable arrangement) in the present invention can be applied as long as it does not bend greatly due to its own weight.

  In the above-described embodiment, the mode in which a plurality of cables are arranged in the lower region of the swivel unit is illustrated. However, the configuration in which a plurality of cables are arranged in the upper region of the swivel unit and the swivel center axis of the swivel unit are not in the vertical direction. For example, it may be a horizontal direction or a direction at a predetermined angle other than 90 degrees with respect to the horizontal direction.

  Also, the part of the cable in the reference state that bulges most in the direction away from the turning center axis is not the central part between the movable end connection position and the fixed end connection position of the cable, but is more movable than the central part. You may employ | adopt the cable process which becomes a part which approached any one side of an edge part connection position or a fixed edge part connection position. In this case, the “specific region” in the “space around the turning center axis surrounded by each cable and inflating the specific region” in claim 1 of the present application is the movable end connecting position and the fixed end of the cable. It means not a region formed by the central portion between the connecting positions but a region formed by a portion closer to either the movable end connecting position or the fixed end connecting position than the central portion.

  Even in such a case, each cable is twisted in accordance with the turning motion of the turning portion by setting the space around the turning center surrounded by the cable in the maximum twisted state so that the arrangement space of the structure can be secured. Even in the case of deformation, it is possible to realize a configuration in which the cable does not interfere with the structure.

  Of the cable deformed from the reference state to the maximum twisted state, the distance from the predetermined part (the part farthest from the turning center in the reference state) between the movable end connecting position and the fixed end connecting position to the turning center However, it is shorter than the distance from the movable end connection position to the turning center, or the distance from the fixed end connection position to the turning center, and a space in which a part of the space around the turning center is confined (the predetermined part is on the turning center side). You may set so that it may become a recessed space. Even in this case, if each cable in the maximum twisted state is set so as not to interfere with the structure disposed in the space around the turning center, the various effects described above can be obtained.

  Moreover, although it is preferable that the cable in the reference state is not twisted at all when captured in units of cables, an aspect in which the cable is twisted by an arbitrary amount in the reference state may be used.

  When the cable is in the reference state, the movable end connection position and the fixed end connection position of each cable are set so that they face each other at an arbitrary angle with respect to the turning center axis direction although they are not directly in front when viewed from the turning center axis direction. May be. For example, when captured in units of cables, if the distance from the movable end connection position to the turning center axis is different from the distance from the fixed end connecting position to the turning center axis, the movable end connection Although the position and the fixed end connection position are not directly in front when viewed from the turning center axis direction, an arbitrary angle with respect to the turning center axis direction (this angle is the distance from the movable end connecting position to the turning center axis, Determined on the basis of the difference in the distance from the joint connection position to the turning center axis).

  In addition, the cable processing according to the present invention is applied to an industrial robot in which the turning unit is set to be turnable up to a predetermined angle only in one direction with reference to the turning angle when the cable is in the reference state (reference angle). It is also possible.

  Moreover, in the above-mentioned embodiment, although the aspect which performs the wiring process of the part withdraw | derived out of cable accommodation space among cables with the cable guide provided outside cable accommodation space was illustrated, cable accommodation space was not used. You may comprise so that it may mount in the cable mounting base (The arrangement location, a shape, and size are not specifically limited) provided outside.

  Furthermore, the specific configurations of the first cable connection portion and the second cable connection portion can be changed as appropriate, and the cable connection portions can have different configurations or the same configuration. .

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 11 ... Hand 12 ... Arm 4 ... Turning part 61, 62 ... Structure (ball screw, ball screw cover)
7 ... 1st cable connection part 8 ... 2nd cable connection part 9 ... Cable 91 ... Movable end part connection position 92 ... Fixed end part connection position 9S ... Space around the turning center axis (space around the turning center)
C: Turning center axis T ... Industrial robot (conveying robot)

Claims (4)

An industrial robot comprising a fixed part and a turning part capable of turning about a turning center axis with respect to the fixed part ,
A movable end connected to the first cable connecting portion relatively close to the turning portion and moving with the turning operation of the turning portion, and a second cable connecting portion relatively far from the turning portion; The fixed end with respect to the second cable connection portion from a movable end connection position that is a connection position of the movable end portion with respect to the first cable connection portion, and has a fixed end portion that does not move even when the turning portion turns. A plurality of cables in which the cable length to the fixed end connection position that is the connection position of the section is set to be longer than the linear distance from the movable end connection position to the fixed end connection position along the turning center axis direction In the reference state where the movable end connection position and the fixed end connection position of each cable face the direction of the turning center axis. The cable bulging amount in which the region between the movable end connecting position and the fixed end connecting position of the cable bulges away from the turning central axis is maximized, and the turning of the turning portion from the reference state Along with the amount of movement of the movable end portion of each cable that increases as the angle increases, each cable is configured to be deformable into a twisted state in which the cable bulge amount decreases,
When each cable is in the reference state, a predetermined structure is arranged in a space around the turning center axis surrounded by each cable and a specific area is expanded, and the turning portion is set to a preset maximum. When turning to a turning angle, the cable is configured so that the cables that are twisted to the maximum twist state do not interfere with the structure .
The plurality of cables are accommodated in a cable accommodating portion formed in an internal space of the fixed portion, and do not interfere with an inner wall of the cable accommodating portion when in the reference state.
An industrial robot characterized in that a motor that outputs a driving force for turning the turning portion with respect to the fixed portion is disposed outside the cable housing portion . The structure is a component of an elevating mechanism that moves the swivel portion so as to be able to move up and down,
The industrial robot according to claim 1, wherein a drive motor serving as a drive source for the elevating mechanism is disposed outside the cable housing portion . The movable end connection positions of the cables are arranged at an equal pitch on a circumference centered on the turning center axis, and are centered on the turning center axis and on a circumference having the same or substantially the same radius as the circumference. The industrial robot according to claim 1 , wherein the fixed end connection positions of the cables are arranged at an equal pitch . What transfer robot der for semiconductor wafer transport with an arm which is pivotably configured around the pivot axis and at least a base end portion provided at the distal end portion forward and backward operable hand along a predetermined moving direction, 4. The industrial robot according to claim 1, wherein the industrial robot is disposed in a wafer transfer chamber for delivering a semiconductor wafer .

Images