Conveying device

Abstract

To provide a conveyance device which is suitable for achieving stabilization of traveling property of a structure part moved by a linear movement mechanism.SOLUTION: A conveyance device A1 includes a fixing base 1, a turning base 2 which is turnably supported by the fixing base 1 around a vertical turning axis Os, a linear movement mechanism 3 supported by the turning base 2, and a first arm 4A which is supported by the linear movement mechanism 3 and is moved along a horizontal and straight movement stroke GL extending in a first direction by operation of the linear movement mechanism 3, wherein the linear movement mechanism 3 includes a linear movement mechanism 3 for transmitting driving force to the first arm 4A and one first guide rail 32A which movably supports the first arm 4A and extends in the first direction, and the first arm 4A is supported by the one first guide rail 32A in a cantilever manner.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a conveying device, and more particularly to a conveying device capable of linearly conveying a workpiece.

Background Art

[0002] Among conveying devices, there are those having a mechanism (linear movement mechanism) for moving a hand along a linear movement stroke. Such a conveying device is frequently used, for example, for loading or unloading thin plate-shaped workpieces such as wafers or glass substrates into or out of each processing chamber in a semiconductor manufacturing process or a liquid crystal display panel manufacturing process.

[0003] As a conveying device for conveying such a thin plate-shaped workpiece, for example, there is one disclosed in Patent Document 1 below. This conveying device includes a fixed base, a swing base rotatably supported on the fixed base, a linear movement mechanism supported on the swing base, and a pair of hands separately supported on the linear movement mechanism. The linear movement mechanism has a pair of drive mechanisms (for example, belt drive mechanisms) for driving each of the pair of hands, and when the drive mechanisms are driven, the hands are linearly moved in the horizontal direction. Thereby, it is possible to separately convey the thin plate-shaped workpieces held by the pair of hands along a horizontal linear movement stroke.

[0004] The linear movement mechanism has guide rails that movably support each of the pair of hands. The pair of hands are each supported by two guide rails. In a configuration where each hand is supported by two guide rails, the support state of the hand is stable. On the other hand, in order to slide the hand supported by the two guide rails along a horizontal linear movement stroke, adjustment of the parallelism of the two guide rails is necessary, and high accuracy is required for sliding travel. Also, in order to slide the pair of hands, four guide rails are required. This leads to an increase in weight and cost, and there was room for improvement.

Prior Art Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2008-272847 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention was conceived under these circumstances, and its main objective is to provide a conveying device suitable for stabilizing the movement of structural parts moved by a linear movement mechanism. [Means for solving the problem]

[0007] To solve the above problems, the present invention employs the following technical means.

[0008] The conveying device provided by the present invention comprises a fixed base, a pivot base supported so as to be pivotable about a pivot axis perpendicular to the fixed base, a linear movement mechanism supported on the pivot base, and a first arm supported on the linear movement mechanism and moving along a horizontal linear movement stroke extending in a first direction by the operation of the linear movement mechanism, wherein the linear movement mechanism includes a first drive mechanism for transmitting a driving force to the first arm, and a first guide rail that movably supports the first arm and extends in the first direction, and the first arm is cantilevered on the first guide rail.

[0009] In a preferred embodiment, the linear motion mechanism further comprises a second arm supported by the linear motion mechanism and moving along the motion stroke extending in the first direction by the operation of the linear motion mechanism, the linear motion mechanism comprising a second drive mechanism for transmitting a driving force to the second arm, and a second guide rail that movably supports the second arm and extends in the first direction, wherein the first guide rail and the second guide rail are spaced apart in a second direction perpendicular to both the vertical and the first direction, and the second arm is cantilevered to the second guide rail.

[0010] In a preferred embodiment, a first end effector can be attached to the first arm, and the first center of gravity position, which is the center of gravity of the first arm and the first end effector, is set to coincide with the one first guide rail in the vertical direction when viewed in the first direction.

[0011] In a preferred embodiment, a second end effector can be attached to the second arm, and the second center of gravity position, which is the center of gravity of the second arm and the second end effector, is set to coincide with the one second guide rail in the vertical direction when viewed in the first direction.

[0012] In a preferred embodiment, the first drive mechanism includes a first drive shaft arranged along a horizontal axis, a plurality of first pulleys including a first drive pulley attached to the first drive shaft, and a first output belt wrapped around the plurality of first pulleys so as to be in a vertical plane and reciprocating over a predetermined section along a parallel line of the movement stroke; the second drive mechanism includes a second drive shaft arranged along a horizontal axis, a plurality of second pulleys including a second drive pulley attached to the second drive shaft, and a second output belt wrapped around the plurality of second pulleys so as to be in a vertical plane and reciprocating over a predetermined section along a parallel line of the movement stroke; and the linear movement mechanism includes a first connecting member connecting the first arm and the first output belt, and a second connecting member connecting the second arm and the second output belt. [Effects of the Invention]

[0013] The conveying device according to the present invention comprises a fixed base, a pivot base supported so as to be pivotable around a pivot axis perpendicular to the fixed base, a linear movement mechanism supported on the pivot base, and a first arm supported on the linear movement mechanism. The first arm moves along a horizontal linear movement path extending in a first direction by the operation of the linear movement mechanism. The linear movement mechanism comprises a first drive mechanism A for transmitting driving force to the first arm, and a first guide rail that supports the first arm so as to be movable and extends in the first direction, and the first arm is cantilevered on the one first guide rail. With this configuration, since the first arm slides while being supported by a single first guide rail, unlike the case where it is supported by, for example, two guide rails, adjustment of the parallelism of the guide rails is unnecessary. Therefore, the stabilization of the movement of the structural part moved by the linear movement mechanism can be improved.

[0014] Other features and advantages of the present invention will become more apparent from the detailed description below with reference to the accompanying drawings. [Brief explanation of the drawing]

[0015] [Figure 1] This is an overall perspective view showing an example of a transport device according to the present invention. [Figure 2] Figure 1 is a perspective view showing an example of the use of the conveying device. [Figure 3] Figure 2 is a plan view of the conveying device shown. [Figure 4] This is a cross-sectional view along the line IV-IV in Figure 3. [Figure 5] This is a partial cross-sectional view along the VV line in Figure 4. [Figure 6] This is a partial cross-sectional view along the line VI-VI in Figure 4. [Figure 7] This is a magnified view of a portion of Figure 4. [Modes for carrying out the invention]

[0016] Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

[0017] Figs. 1 to 7 show an example of a transfer device according to the present invention. As shown in Figs. 1 to 4, the transfer device A1 includes a fixed base 1, a swivel base 2 that is supported so as to be swivellable around a swivel axis Os perpendicular to the fixed base 1, a linear movement mechanism 3 supported by the swivel base 2, and a first arm 4A and a second arm 4B separately supported by the linear movement mechanism 3. Fig. 2 shows an example of the usage state of the transfer device A1. A first end effector 5A, a second end effector 5B, and a work unit 7 are attached to the transfer device A1. The transfer device A1 of the present embodiment is used, for example, to transfer a thin plate-shaped glass substrate. Although details will be described later, in the transfer device A1, the weight load of the glass substrate, which is the workpiece (transfer target), is not received, or hardly received, by the first arm 4A, the second arm 4B, etc.

[0018] As clearly shown in Fig. 4, the fixed base 1 includes a housing 10 having a substantially cylindrical outer shape, which includes a bottom wall portion 11, a cylindrical side wall portion 12, and a ceiling wall 13. A central opening 13A is formed in the ceiling wall 13.

[0019] Inside the fixed base 1, a lifting base 14 is supported. The lifting base 14 has a cylindrical portion 141 having an outer diameter smaller than that of the central opening 13A and having a predetermined dimension in the vertical direction, and an outward flange portion 142 formed at the lower end of the cylindrical portion 141. A plurality of linear guide rails 15 in the vertical direction are attached to the inner wall of the side wall portion 12 of the housing 10, and a plurality of guide members 16 provided on the outward flange portion 142 of the lifting base 14 are supported so as to be slidable in the vertical direction with respect to the linear guide rails 15. Thereby, the lifting base 14 is movable within a predetermined range in the vertical direction with respect to the fixed base 1, and at this time, the upper part of the cylindrical portion 141 of the lifting base 14 protrudes from and retracts into the central opening 13A of the housing 10.

[0020] Between the ceiling wall 13 of the fixed base 1 and the outer flange portion 142 of the elevating base 14, both ends of a bellows 17 arranged so as to surround the cylindrical portion 141 of the elevating base 14 are connected. This bellows 17 hermetically seals between the ceiling wall 13 of the fixed base 1 and the outer flange portion 142 of the elevating base 14 regardless of the vertical movement of the elevating base 14.

[0021] Inside the fixed base 1, also on the outside of the bellows 17, there is arranged a ball screw mechanism 18 composed of a screw shaft 181 arranged vertically in the z - direction and rotating, and a nut member 182 screwed onto this screw shaft 181 and fixedly penetrated in the outer flange portion 142 of the elevating base 14. The screw shaft 181 is linked to a motor M1 by a belt 184 wound around a pulley 183 attached to the lower end thereof, and is rotated in the forward and reverse directions by driving this motor M1. By rotating the screw shaft 181 in this way, the elevating base 14 is elevated and lowered.

[0022] As shown in FIG. 4, the swivel base 2 includes a cylindrical shaft 21 and an upper plate 22 integrally connected above it. The cylindrical shaft 21 is rotatably supported about a swivel axis Os via a bearing 231 inside the cylindrical portion 141 of the elevating base 14. A seal mechanism 232 is also interposed between the cylindrical portion 141 and the cylindrical shaft 21, above the bearing 231. The seal mechanism 232 shields the space above the seal mechanism 232 and the inner space of the elevating base 14 below the seal mechanism 232 to maintain airtightness. An integrally formed pulley 211 is provided at the lower end of the cylindrical shaft 21, and a belt 241 is wound around between this pulley 211 and a pulley attached to the output shaft of a motor M2 supported inside the cylindrical portion 141. Thereby, when the motor M2 is driven, the swivel base 2 swivels around the swivel axis Os.

[0023] As shown in Figure 4, a first transmission shaft 25 and a second transmission shaft 26, which transmit driving force to the first drive mechanism 33A and the second drive mechanism 33B (described later), are coaxially inserted along the pivot axis Os on the cylindrical shaft 21 of the slewing base 2. The first transmission shaft 25 is a cylindrical shaft and is rotatably supported inside the cylindrical shaft 21 via a bearing 233. The second transmission shaft 26 is rotatably supported inside the first transmission shaft 25 via a bearing 234. The lower end of the second transmission shaft 26 is connected to the output shaft of the motor M4, which is supported within the cylindrical section 141. A bevel gear is provided at the upper end of the second transmission shaft 26. On the other hand, a pulley 251 is provided at the lower end of the first transmission shaft 25, and a belt 242 is wrapped between this pulley 251 and a pulley attached to the output shaft of the motor M3, which is supported within the cylindrical section 141. A bevel gear is provided at the upper end of the first transmission shaft 25.

[0024] The linear movement mechanism 3 is for transporting the first arm 4A and the second arm 4B along a horizontal linear movement path GL extending in the first direction x. As shown in Figure 4, the linear movement mechanism 3 includes a guide member 31, a first guide rail 32A and a second guide rail 32B provided on the guide member 31, a first drive mechanism 33A and a second drive mechanism 33B that transmit horizontal driving force to the first arm 4A and the second arm 4B, and a first connecting member 35A and a second connecting member 35B.

[0025] The guide member 31 has a long rectangular shape in plan view, with a longitudinal axis (movement stroke GL) extending horizontally, and includes a bottom wall 311, side walls 312, a middle wall 313, and a cover 314. The guide member 31 is also fixed to the upper plate 22 of the swivel base 2, and when the swivel base 2 is swiveled, the guide member 31 rotates in conjunction with it. The space between the bottom wall 311 of the guide member 31 and the upper plate 22 of the swivel base 2 is airtightly sealed by a sealing member (not shown). In this embodiment, one first guide rail 32A and one second guide rail 32B are fixedly positioned at appropriate locations on the guide member 31.

[0026] The first guide rail 32A and the second guide rail 32B each extend in the first direction x. As shown in Figure 4, the first guide rail 32A and the second guide rail 32B are spaced apart in the second direction y, which is perpendicular to both the first direction x (the direction perpendicular to the plane of the paper in Figure 4) and the vertical direction z. The first guide rail 32A is located on one side of the second direction y (left side in the figure), and the second guide rail 32B is located on the other side of the second direction y (right side in the figure).

[0027] The first arm 4A is supported on the first guide rail 32A via the first slider 321A. The first arm 4A has a connecting portion 41a and a main portion 42a. The connecting portion 41a is fixed to the first slider 321A. The main portion 42a is connected to the connecting portion 41a and is located outside the guide member 31. The main portion 42a is formed to bypass the side of the workpiece unit 7 (left side in Figure 4). The illustrated first arm 4A is cantilevered to one of the first guide rails 32A via the first slider 321A. The first arm 4A is made of, for example, a metal material having moderate strength.

[0028] The first arm 4A (connecting portion 41a) passes through a slit 314a formed on the side surface of the cover 314, and a first connecting member 35A is provided on the connecting portion 41a. The first connecting member 35A passes through a slit 312a formed in the side wall 312 and is connected to the first output belt 337A of the first drive mechanism 33A, which will be described later. In this way, the first connecting member 35A connects the first arm 4A and the first output belt 337A.

[0029] The second arm 4B is supported on the second guide rail 32B via the second slider 321B. The second arm 4B has a connecting portion 41b and a main portion 42b. The connecting portion 41b is fixed to the second slider 321B. The main portion 42b is connected to the connecting portion 41b and is located outside the guide member 31. The illustrated second arm 4B is cantilevered to one of the second guide rails 32B via the second slider 321B. The second arm 4B is made of, for example, a metal material having moderate strength.

[0030] The second arm 4B passes through a slit 314b formed on the upper surface of the cover 314, and a second connecting member 35B is provided at the connecting portion 41b. The second connecting member 35B is connected to the second output belt 337B of the second drive mechanism 33B, which will be described later. In this way, the second connecting member 35B connects the second arm 4B and the second output belt 337B.

[0031] As shown in Figures 1, 2, and 4, the tip of the first arm 4A (main part 42a) and the second arm 4B (main part 42b) overlap in a plan view (viewed in the vertical direction z). The tip of the first arm 4A (main part 42a) is located above the second arm 4B (main part 42b) in the vertical direction z.

[0032] The first drive mechanism 33A and the second drive mechanism 33B are for moving the first arm 4A and the second arm 4B separately along the movement path GL. Since the first drive mechanism 33A and the second drive mechanism 33B have basically the same configuration, the configuration of the first drive mechanism 33A will be described in detail below, and the explanation of the second drive mechanism 33B will be omitted as appropriate.

[0033] As shown in Figures 4 and 5, the first drive mechanism 33A comprises a transmission shaft 331a, a first drive shaft 332a, a first bevel gear mechanism 333A, a reduction mechanism 334, a first drive pulley 335a, pulleys 335b to 335g, and a first output belt 337A, and is housed within a guide member 31. The transmission shaft 331a is supported by the guide member 31 so as to be rotatable around a horizontal axis O1 that is perpendicular to the pivot axis Os. A bevel gear is provided at one end of the transmission shaft 331a (right side in the figure), and this bevel gear meshes with a bevel gear provided at the upper end of the first transmission shaft 25. The first bevel gear mechanism 333A consists of a bevel gear at the upper end of the first transmission shaft 25 and a bevel gear at one end of the transmission shaft 331a, and is intended to convert the rotation of the first transmission shaft 25 around the pivot axis Os into rotation around the horizontal axis O1 and transmit it to the first drive pulley 335a. The other end of the transmission shaft 331a is connected to the input shaft of the reduction mechanism 334.

[0034] The first drive shaft 332a is supported by a guide member 31 so as to be rotatable around a horizontal axis O1. One end of the first drive shaft 332a is connected to the output shaft of a reduction mechanism 334. A first drive pulley 335a is provided at the other end (left side in the figure) of the first drive shaft 332a. A sealing mechanism 338 is interposed between the first drive shaft 332a and the guide member 31. This sealing mechanism 338 provides an airtight seal to the inside space of the lifting base 14, which communicates with the inside of the guide member 31 via the swivel base 2, from the outside. A coupling joint (not shown) may be provided between the transmission shaft 331a and the first drive shaft 332a if necessary.

[0035] As shown in Figure 5, pulleys 335b to 335g are each supported within the guide member 31 so as to be rotatable around a predetermined horizontal axis. The first output belt 337A is wrapped around the first drive pulley 335a and pulleys 335b to 335g (collectively known as the first pulleys) along a vertical plane. Pulleys 335b and 335c are located near both ends of the guide member 31 in the longitudinal direction (the direction along the travel stroke GL). On the other hand, pulleys 335d, 335e, 335f, and 335g are located near the first drive pulley 335a, and pulleys 335f and 335g are positioned outside the first output belt 337A and press against it. As a result, the first output belt 337A is subjected to appropriate tension. For the first output belt 337A, a timing belt is preferably used, for example.

[0036] With this configuration, when the motor M3 is driven, the rotational driving force of the motor M3 is transmitted to the first drive mechanism 33A via the belt 242 and the first transmission shaft 25. In the first drive mechanism 33A, the axial direction of rotation is converted from rotation around the pivot axis Os to rotation around the horizontal axis O1 by the first bevel gear mechanism 333A, and the rotation is reduced by the reduction mechanism 334 before the first drive pulley 335a is rotated. As the first drive pulley 335a rotates, the first output belt 337A reciprocates within a predetermined vertical plane.

[0037] The pulleys 335b and 335c are arranged along a line parallel to the travel path GL. In Figure 5, the region of the first output belt 337A located below the pulleys 335b and 335c is a section 34a parallel to the travel path GL, and the first output belt 337A is configured to reciprocate within this section 34a. The other end of the first connecting member 35A, one end of which is connected to the connecting portion 41a of the first arm 4A, is connected to a predetermined portion of the section 34a of the first output belt 337A. As a result, the first arm 4A slides horizontally along the travel path GL while being cantilevered on one first guide rail 32A by the drive of the first drive mechanism 33A.

[0038] As shown in Figures 4 and 6, the second drive mechanism 33B comprises a transmission shaft 331b, a second drive shaft 332b, a second bevel gear mechanism 333B, a reduction mechanism 334, a second drive pulley 336a, pulleys 336b to 336g, and a second output belt 337B, and is housed within the guide member 31. The transmission shaft 331b and the second drive shaft 332b are positioned on the opposite side of the pivot axis Os from the transmission shaft 331a and the first drive shaft 332a of the first drive mechanism 33A, and are rotatably supported by the guide member 31 around the horizontal axis O1. A bevel gear is provided at one end of the transmission shaft 331b (left side in the figure), and this bevel gear meshes with a bevel gear provided at the upper end of the second transmission shaft 26. The second bevel gear mechanism 333B consists of a bevel gear at the upper end of the second transmission shaft 26 and a bevel gear at one end of the transmission shaft 331b, and is intended to convert the rotation of the second transmission shaft 26 around the pivot axis Os into rotation around the horizontal axis O1 and transmit it to the second drive pulley 336a. The other end of the transmission shaft 331b is connected to the input shaft of the reduction mechanism 334.

[0039] The second drive shaft 332b is supported by a guide member 31 so as to be rotatable around the horizontal axis O1. One end of the second drive shaft 332b is connected to the output shaft of the reduction mechanism 334. The other end (right side in the figure) of the second drive shaft 332b is provided with a second drive pulley 336a.

[0040] As shown in Figure 6, pulleys 336b to 336g are each supported within the guide member 31 so as to be rotatable around a predetermined horizontal axis. The arrangement of pulleys 336b to 336g is inverted vertically from the arrangement of pulleys 335b to 335g in the first drive mechanism 33A. The second output belt 337B is wrapped around the second drive pulley 336a and pulleys 336b to 336g (collectively, a plurality of 21 pulleys) along a vertical plane. Pulleys 336b and 336c are provided near both ends of the guide member 31 in the longitudinal direction (direction along the movement stroke GL). On the other hand, pulleys 336d, 336e, 336f, and 336g are located near the second drive pulley 336a, and pulleys 336f and 336g are positioned outside the second output belt 337B and press against it. As a result, the second output belt 337B is subjected to appropriate tension. A timing belt is preferably used as the second output belt 337B.

[0041] When the motor M4 is driven, the rotational driving force of the motor M4 is transmitted to the second drive mechanism 33B via the second transmission shaft 26. In the second drive mechanism 33B, the axial direction of rotation is converted from rotation around the pivot axis Os to rotation around the horizontal axis O1 by the second bevel gear mechanism 333B, and the second drive pulley 336a is rotated after being reduced by the reduction mechanism 334. As the second drive pulley 336a rotates, the second output belt 337B reciprocates within a predetermined vertical plane.

[0042] The pulleys 335b and 335c are arranged along a line parallel to the travel path GL. In Figure 6, the region of the second output belt 337B located above the pulleys 336b and 336c is a section 34b parallel to the travel path GL, and the second output belt 337B is configured to reciprocate within this section 34b. The other end of a second connecting member 35B, one end of which is connected to the connecting portion 41b of the second arm 4B, is connected to a predetermined portion of the section 34b of the second output belt 337B. As a result, the second arm 4B slides horizontally along the travel path GL while being cantilevered on one second guide rail 32B by the drive of the second drive mechanism 33B.

[0043] The first end effector 5A, shown in Figures 2 to 4, is detachably attached to the first arm 4A and is used to transport the workpiece 8 (described later) from inside the workpiece unit 7 to a processing chamber or load lock chamber (not shown) located on one side of the first direction x (left side in Figure 3), and to transport the workpiece 8 from the processing chamber or load lock chamber (not shown) back into the workpiece unit 7. The first end effector 5A has a mounting portion 51a and a pair of tip portions 52a, and these mounting portion 51a and the pair of tip portions 52a are connected by a bifurcated fork portion. The mounting portion 51a is made of, for example, a metal plate and is attached directly below the tip of the first arm 4A (main portion 42a). The entire first end effector 5A is positioned so as to be substantially aligned with the horizontal plane. Detailed illustrations are omitted, but locking portions for securing the workpiece 8 are provided at appropriate locations on the tip portions 52a.

[0044] The second end effector 5B is detachably attached to the second arm 4B and is used to load the workpiece 8 from the workpiece unit 7 into a processing chamber or load lock chamber (not shown), and to load the workpiece 8 from the processing chamber or load lock chamber (not shown) into the workpiece unit 7. The second end effector 5B has the same configuration as the first end effector 5A. The second end effector 5B has a mounting portion 51b and a pair of tip portions 52b, and these mounting portion 51b and the pair of tip portions 52b are connected by a bifurcated fork portion. The mounting portion 51b is made of, for example, a metal plate and is mounted directly above the tip portion of the second arm 4B (main portion 42b). The second end effector 5B is positioned so that the entire structure is substantially aligned with the horizontal plane. In the second end effector 5B, as in the first end effector 5A, locking portions (not shown) for locking the workpiece 8 are provided at appropriate locations on the tip portions 52b.

[0045] Alternatively, the first end effector 5A can be used for loading into the processing room, etc., and the second end effector 5B can be used for unloading from the processing room, etc. Conversely, the second end effector 5B can be used for loading into the processing room, etc., and the first end effector 5A can be used for unloading from the processing room, etc.

[0046] As shown in Figure 2, the first end effector 5A and the second end effector 5B overlap each other in a plan view (view in the vertical direction z). The first end effector 5A is positioned above the second end effector 5B in the vertical direction z. The first end effector 5A slides horizontally along the movement path GL while being supported by a first guide rail 32A via a first arm 4A. The second end effector 5B slides horizontally along the movement path GL while being supported by a second guide rail 32B via a second arm 4B.

[0047] The workpiece unit 7 bears the weight load of the workpiece 8 during transport. As shown in Figure 1, a base 6 is provided at an appropriate location on the cover 314 of the guide member 31. In the illustrated example, a pair of bases 6 are arranged spaced apart in the second direction y. Each base 6 has, for example, a rectangular cross-section and extends in the first direction x. The workpiece unit 7 is attached to the pair of bases 6 and is supported by the guide member 31 via the pair of bases 6.

[0048] As shown in Figures 2 to 4, the workpiece unit 7 comprises side walls 70 and support plates 71. The side walls 70 are arranged in pairs so as to be separated in the second direction y. The support plates 71 are located in the region sandwiched between the pair of side walls 70 in a plan view (viewed in the vertical direction z). The support plates 71 are provided in two stages, upper and lower, separated by a gap in the vertical direction z, and the support plates 71 of each stage are arranged to be substantially parallel to the horizontal plane. In the illustrated example, the upper support plate 71 consists of a single rectangular plate-shaped section extending in a series in the second direction y, and the lower support plate 71 consists of two rectangular plate-shaped sections separated in the second direction y. Figure 3 is a transparent view of the workpiece unit 7, and the workpiece unit 7 is represented by dashed lines.

[0049] The first end effector 5A moves directly above the upper support plate 71 of the work unit 7 when transporting the workpiece 8 from the work unit 7 to a processing chamber (not shown) and when transporting the workpiece 8 from the processing chamber (not shown). The second end effector 5B moves between the lower support plate 71 and the upper support plate 71 of the work unit 7 when transporting the workpiece 8 from the work unit 7 to a processing chamber (not shown) and when transporting the workpiece 8 from the processing chamber (not shown).

[0050] As shown in Figures 3 and 4, the workpiece 8 transported by the transport device A1 can be placed inside the workpiece unit 7. The workpiece 8 transported from inside the workpiece unit 7 to a processing room (not shown) by the first end effector 5A is placed on the upper support plate 71 of the workpiece unit 7. The workpiece 8 transported from inside the workpiece unit 7 to a processing room (not shown) by the second end effector 5B is placed on the lower support plate 71 of the workpiece unit 7.

[0051] In this embodiment, the workpiece 8 is, for example, a glass substrate for a liquid crystal display panel. The workpiece 8 is rectangular in shape. A detailed illustration is omitted, but locking portions are provided at appropriate locations on the workpiece 8. The locking portions provided on the workpiece 8 are configured to lock onto the locking portions provided on the tip portion 52a (tip portion 52b) of the first end effector 5A (second end effector 5B). For example, the locking portion on the first end effector 5A (second end effector 5B) side has a pin, and the locking portion on the workpiece 8 side has a locking hole, and by inserting the pin into the locking hole, the locking portion on the workpiece 8 side is locked onto the locking portion on the first end effector 5A (second end effector 5B) side. The workpiece 8 is locked by the first end effector 5A (second end effector 5B), and the locking can be released by the lifting and lowering operation of the lifting base 14. Note that Figures 3 and 4 show workpiece 8 with transparency, and workpiece 8 is represented by dashed lines.

[0052] In the process of loading and unloading the workpiece 8 into and out of the workpiece unit 7 by the first end effector 5A and the second end effector 5B, the workpiece 8 is moved along the movement path GL while sliding on the support plate 71. Preferably, the upper surface of the support plate 71 is made of a low-friction material so as to reduce the sliding resistance of the workpiece 8. For example, the entire support plate 71 may be made of a low-friction material, or the surface (at least the upper surface) of the support plate 71 may be coated with a low-friction material (for example, molybdenum plating).

[0053] During the process of loading and unloading the workpiece 8 into and out of the workpiece unit 7 by the first end effector 5A and the second end effector 5B, and while the workpiece 8 is positioned within the workpiece unit 7, the weight load of the workpiece 8 is borne by the guide member 31 via the workpiece unit 7. Therefore, during the transport of the workpiece 8, the weight load of the workpiece 8 is not applied to the first end effector 5A and the second end effector 5B, nor to the first arm 4A and the second arm 4B that support them.

[0054] In this embodiment, as shown in Figures 2 to 4 and Figure 7, a weight 44a is provided on the first arm 4A. Also, as shown in Figures 4, 6 and 7, a weight 44b is provided on the second arm 4B. In the illustrated example, the weight 44a is provided at the tip of the main portion 42a of the first arm 4A. The weight 44b is provided at the lower part of the connecting portion 41b of the second arm 4B.

[0055] As shown in Figure 7, by providing a weight 44a on the first arm 4A, the first center of gravity position C1, which is the center of gravity of the first arm 4A and the first end effector 5A, coincides with the first guide rail 32A in the vertical direction z when viewed in the first direction x. Therefore, by providing the weight 44a, the first center of gravity position C1, which is the center of gravity of the first arm 4A and the first end effector 5A, is appropriately set to coincide with the first guide rail 32A in the vertical direction z when viewed in the first direction x. Note that the original center of gravity position C10 of the first arm 4A and the first end effector 5A when the weight 44a is not provided is deviated to one side of the second direction y (left side in the figure) compared to the first center of gravity position C1.

[0056] As shown in Figure 7, by providing a weight 44b to the second arm 4B, the second center of gravity position C2, which is the center of gravity of the second arm 4B and the second end effector 5B, coincides with the second guide rail 32B in the vertical direction z when viewed in the first direction x. Therefore, by providing the weight 44b, the second center of gravity position C2, which is the center of gravity of the second arm 4B and the second end effector 5B, is appropriately set to coincide with the second guide rail 32B in the vertical direction z when viewed in the first direction x. Note that the original center of gravity position C20 of the second arm 4B and the second end effector 5B when the weight 44b is not provided is deviated to one side of the second direction y (left side in the figure) compared to the second center of gravity position C2.

[0057] Next, the operation of this embodiment will be described.

[0058] The transport device A1 comprises a fixed base 1, a pivot base 2 supported so as to be pivotable around a pivot axis Os perpendicular to the fixed base 1, a linear movement mechanism 3 supported on the pivot base 2, and a first arm 4A supported on the linear movement mechanism 3. The first arm 4A moves along a horizontal linear movement path GL extending in a first direction x by the operation of the linear movement mechanism 3. The linear movement mechanism 3 comprises a first drive mechanism 33A for transmitting driving force to the first arm 4A, and a first guide rail 32A that supports the first arm 4A so as to be movable and extends in the first direction x, and the first arm 4A is cantilevered on the one first guide rail 32A. With this configuration, the first arm 4A slides while being supported by a single first guide rail 32A, so unlike when it is supported by, for example, two guide rails, adjustment of the parallelism of the guide rails is unnecessary. Therefore, the movement of the structural parts (first arm 4A and first end effector 5A) moved by the linear movement mechanism 3 can be stabilized.

[0059] The transport device A1 includes a second arm 4B supported by a linear movement mechanism 3, and the second arm 4B moves along a horizontal linear movement path GL extending in a first direction x by the operation of the linear movement mechanism 3. The linear movement mechanism 3 includes a second drive mechanism 33B for transmitting driving force to the second arm 4B, and a second guide rail 32B that movably supports the second arm 4B and extends in the first direction x. The first guide rail 32A and the second guide rail 32B are spaced apart in a second direction y (a direction perpendicular to both the vertical direction z and the first direction x), and the second arm 4B is cantilevered on one of the second guide rails 32B. With this configuration, the second arm 4B slides while being supported by a single second guide rail 32B, so unlike when it is supported by, for example, two guide rails, adjustment of the parallelism of the guide rails is unnecessary. Therefore, the movement of the structural parts moved by the linear movement mechanism 3 (the first arm 4A and first end effector 5A, and the second arm 4B and second end effector 5B mentioned above) can be stabilized. In addition, since only two guide rails (first guide rail 32A and second guide rail 32B) are required to slide the pair of first arms 4A and second arms 4B, it is possible to miniaturize and lighten the linear movement mechanism 3.

[0060] In this embodiment, the first center of gravity position C1, which is the center of gravity of the first arm 4A and the first end effector 5A, is set to coincide with the first guide rail 32A in the vertical direction z when viewed in the first direction x. With this configuration, the moment load acting on the first guide rail 32A can be reduced, and the lifespan of the first guide rail 32A, which cantilever-supports the first arm 4A, etc., is extended. Similarly, the second center of gravity position C2, which is the center of gravity of the second arm 4B and the second end effector 5B, is set to coincide with the second guide rail 32B in the vertical direction z when viewed in the first direction x. With this configuration, the moment load acting on the second guide rail 32B can be reduced, and the lifespan of the second guide rail 32B, which cantilever-supports the second arm 4B, etc., is extended.

[0061] The first drive mechanism 33A (and the second drive mechanism 33B) are each composed of belt-type drive mechanisms. The first arm 4A (and the second arm 4B) is connected to the first output belt 337A (and the second output belt 337B) via the first connecting member 35A (and the second connecting member 35B). With this configuration, for example, when the travel distance of the first arm 4A (and the second arm 4B) is extended due to an increase in the size of the workpiece 8, this can be easily accommodated by lengthening the first guide rail 32A (and the second guide rail 32B) and the first output belt 337A (and the second output belt 337B). Therefore, it is possible to appropriately avoid the linear movement mechanism 3 becoming heavier due to the increased travel distance of the first arm 4A (and the second arm 4B). Furthermore, the first arm 4A (and the second arm 4B) is supported by one first guide rail 32A (and one second guide rail 32B). This makes it possible to suppress meandering during sliding motion, unlike when the first arm 4A (second arm 4B) is supported by two guide rails.

[0062] Although embodiments of the present invention have been described above, the scope of the present invention is not limited to the embodiments described above, and any modifications within the scope of the matters described in each claim are all included within the scope of the present invention.

[0063] In the above embodiment, the first drive mechanism 33A (second drive mechanism 33B) was configured to include a first bevel gear mechanism 333A (second drive mechanism 33B) and a reduction mechanism 334, but the specific configuration of the first drive mechanism 33A (second drive mechanism 33B) can be changed in various ways. It is sufficient that the driving force of the motor M3 (motor M4) can be output as rotation around the horizontal axis O1. Also, in the above embodiment, the first drive shaft 332a and the second drive shaft 332b were supported so as to be rotatable around a common horizontal axis O1, but the first drive shaft 332a and the second drive shaft 332b may be supported so as to be rotatable around different horizontal axes.

[0064] The workpiece to be transported by the transport device according to the present invention is not limited to the glass substrate of the above embodiment. Furthermore, in the above embodiment, the workpiece 8 was configured to slide directly on the support plate 71 within the workpiece unit 7, but other configurations are also possible. For example, the workpiece unit may be provided with rollers to support the workpiece, and the workpiece may be configured to slide on these rollers when being transported into or out of the workpiece unit. Alternatively, permanent magnets may be provided at appropriate locations on the workpiece unit and the workpiece, and the workpiece may be configured to levitate magnetically within the workpiece unit due to the repulsive force of the permanent magnets. [Explanation of symbols]

[0065] A1: Conveyor device, 1: Fixed base, 2: Swivel base, 3: Linear movement mechanism, 32A: First guide rail, 32B: Second guide rail, 33A: First drive mechanism, 33B: Second drive mechanism, 335a: First drive pulley, 336a: Second drive pulley, 337A: First output belt, 337B: Second output belt, 34a, 34b: Section, 35A: First connecting member, 35B: Second connecting member, 4A: First arm, 4B: Second arm, 5A: First end effector, 5B: Second end effector, C1: First center of gravity position, C2: Second center of gravity position, GL: Movement stroke, Os: Swivel axis, O1: Horizontal axis, x: First direction, y: Second direction, z: Vertical direction

Claims

1. Fixed base and A pivot base supported so as to be able to pivot around a pivot axis perpendicular to the fixed base, A linear movement mechanism supported by the aforementioned pivot base, It comprises a first arm and a second arm supported by the linear movement mechanism, which move along a horizontal linear movement path extending in a first direction by the operation of the linear movement mechanism, The linear movement mechanism includes a guide member, a first drive mechanism for transmitting driving force to the first arm, a first guide rail that movably supports the first arm and extends in the first direction, a second drive mechanism for transmitting driving force to the second arm, and a second guide rail that movably supports the second arm and extends in the first direction. The first guide rail and the second guide rail are arranged on the guide member at a distance from each other in a second direction perpendicular to both the vertical direction and the first direction. The first arm is cantilevered to one of the first guide rails, The second arm is cantilevered to the first second guide rail, The system further comprises a first end effector attached to the first arm, a second end effector attached to the second arm and positioned vertically below the first end effector, and a workpiece unit supported by the guide member. The first center of gravity position, which is the center of gravity of the first arm and the first end effector, is set to coincide with the one first guide rail in the vertical direction when viewed in the first direction. The second center of gravity position, which is the center of gravity of the second arm and the second end effector, is set to coincide with the one second guide rail in the vertical direction when viewed in the first direction. The workpiece unit is provided in correspondence with the first end effector and the second end effector, and comprises a conveying device with two vertically spaced support plates.

2. The first drive mechanism includes a first drive shaft arranged along a horizontal axis, a plurality of first pulleys including a first drive pulley attached to the first drive shaft, and a first output belt wrapped around the plurality of first pulleys so as to be in a vertical plane and reciprocating over a predetermined section along a parallel line of the movement stroke. The second drive mechanism includes a second drive shaft arranged along a horizontal axis, a plurality of second pulleys including a second drive pulley attached to the second drive shaft, and a second output belt wrapped around the plurality of second pulleys so as to be in a vertical plane and reciprocating over a predetermined section along a parallel line of the travel stroke. The conveying device according to claim 1, wherein the linear movement mechanism includes a first connecting member that connects the first arm and the first output belt, and a second connecting member that connects the second arm and the second output belt.

Images