Conveyor stage

Abstract

To provide a transportation stage which can be operated with high accuracy while reducing costs.SOLUTION: A transportation stage includes: a square steel pipe 21; linear motion guide devices 13 provided at the square steel pipe 21; a table 15 movably supported by the linear motion guide devices 13; and a drive part 17 which moves the table 15. In the square steel pipe 21, reinforcement ribs 41 are fixed and installation portions of the linear motion guide devices 13 are reinforced by the reinforcement ribs 41.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a transfer stage.

Background Art

[0002] For example, in a transfer stage used in a liquid crystal manufacturing apparatus or the like, a square steel pipe may be used as a gantry for reasons such as reduction of manufacturing man-hours.

[0003] As a technique using such a square steel pipe as a gantry, Patent Document 1 discloses a linear motion device in which a hollow structure body that is a square steel pipe is used as a gantry, and a linear drive mechanism portion linearly moves along a toothed rail supported by this gantry.

[0004] Further, Patent Document 2 discloses a positioning device that provides linear motion guide devices on both sides of a base of a can manufacturing structure constructed by connecting a plurality of can materials in the same plane and guiding a beam by these linear motion guide devices.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in the technique described in Patent Document 1, it is necessary to highly accurately process the upper surface of the hollow structure body that is the mounting surface of the toothed rail. However, when the hollow structure body becomes long, it becomes difficult to ensure high processing accuracy. For this reason, the accuracy of the toothed rail attached to the mounting surface formed by the upper surface of the hollow structure body decreases, and the accuracy of the linear motion of the linear drive mechanism portion decreases.

[0007] Furthermore, the technology described in Patent Document 2 above involves connecting multiple can materials on the same plane to create the base of the can structure, resulting in a complex base structure that requires considerable effort to manufacture and incurs high costs.

[0008] Therefore, the present invention aims to provide a transport stage that can operate with high precision while keeping costs down. [Means for solving the problem]

[0009] The present invention consists of the following configuration. Rectangular steel pipe and A linear motion guide device provided on the aforementioned rectangular steel pipe, A table supported so as to be movable by the aforementioned linear motion guide device, A drive unit for moving the table, Equipped with, The aforementioned rectangular steel pipe has reinforcing ribs fixed inside, and the location where the linear motion guide device is installed is reinforced by these reinforcing ribs. Transport stage. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a transport stage that can be operated with high precision while keeping costs down. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view of the transport stage according to the first embodiment. [Figure 2] This is a perspective view of the base that makes up the transport stage. [Figure 3] This is a cross-sectional view of AA in Figure 2. [Figure 4] This is a perspective view of the base with reinforcing ribs of a different shape. [Figure 5] Figure 4 is a cross-sectional view of BB. [Figure 6] This is a perspective view of a transport stage equipped with other drive units. [Figure 7]It is a perspective view of a transfer stage according to the second embodiment. [Figure 8] It is a view seen from the arrow C direction in FIG. 7. [Figure 9] FIG. 9 is a view showing a state before inserting a pair of reinforcing ribs 91 into the square steel pipe 71. [Figure 10] FIG. 10 is a view showing a state after inserting a pair of reinforcing ribs 91 into the square steel pipe 71. [Figure 11] It is an equivalent view seen from the arrow C direction in FIG. 7 of the transfer stage without reinforcing ribs for explaining deformation during transfer. [Figure 12] It is a perspective view of a transfer stage provided with other drive units.

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (First Embodiment) First, the transfer stage according to the first embodiment will be described. FIG. 1 is a perspective view of a transfer stage 100 according to the first embodiment. As shown in FIG. 1, the transfer stage 100 according to the first embodiment includes a base 11, a linear motion guide device 13, a table 15, and a drive unit 17. The transfer stage 100 is used, for example, as a transfer device such as a liquid crystal manufacturing apparatus. The table 15 is formed in a flat plate shape with its upper surface serving as a mounting surface, and is reciprocated by the drive unit 17. Thereby, the transfer stage 100 transfers the workpiece W placed on the upper part of the table 15 along the transfer direction X.

[0013] FIG. 2 is a perspective view of the base 11 constituting the transfer stage 100. FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2.

[0014] As shown in Figures 2 and 3, the base 11 has a long rectangular steel pipe 21. Multiple bottom plates 23 are fixed to the bottom of the rectangular steel pipe 21. These bottom plates 23 are spaced apart in the longitudinal direction of the rectangular steel pipe 21. As a result, the rectangular steel pipe 21 is placed on the floor surface via the bottom plates 23.

[0015] A long support member 25 is fixed to the upper part of the rectangular steel pipe 21. This support member 25 has a flat fixed plate portion 27 and a pair of support rails 29 that protrude upward from the upper surface of the fixed plate portion 27. The support rails 29 are formed on the upper surface of the fixed plate portion 27 at intervals in the width direction, so that the support member 25 is formed in a concave shape in cross-section. A linear motion guide device 13 is attached to the upper surface of the support rails 29 on this support member 25.

[0016] The rectangular steel pipe 21 is a steel pipe with a square cross-section, and can be made of general structural carbon steel pipe (STKR material) or cold-formed rectangular steel pipe (BCR material), for example. When installed, the lower side of the rectangular steel pipe 21 is the bottom surface 31, the upper side is the top surface 33, and both sides are the side surfaces 35. A bottom plate 23 is fixed to the bottom surface 31 of the rectangular steel pipe 21, and a support member 25 is fixed to the top surface 33. In addition, end plates 37 are welded to both ends of the rectangular steel pipe 21, closing the openings at both ends of the rectangular steel pipe 21.

[0017] The rectangular steel pipe 21 has reinforcing ribs 41 made of multiple plates inside. In this example, the rectangular steel pipe 21 has two reinforcing ribs 41. The reinforcing ribs 41 have an outer shape that is slightly smaller than the inner shape of the rectangular steel pipe 21 and are fitted into the rectangular steel pipe 21. These reinforcing ribs 41 are spaced apart in the longitudinal direction of the rectangular steel pipe 21 and are fixed along the width direction of the rectangular steel pipe 21. Specifically, the reinforcing ribs 41 are fitted inside the rectangular steel pipe 21 and are arranged along a plane perpendicular to the longitudinal direction of the rectangular steel pipe 21, and their peripheral edges are welded to the inner circumference of the rectangular steel pipe 21 for fixation. These reinforcing ribs 41 are provided above the bottom plate 23 fixed to the bottom surface 31 of the rectangular steel pipe 21. The rectangular steel pipe 21 having the reinforcing ribs 41 has a circular window portion 39 at a position corresponding to the installation position of the reinforcing ribs 41 on the side portion 35. These window sections 39 are sealed by sealing plates 43 fixed to the outer surface of the side section 35 (see Figure 1).

[0018] When manufacturing the base 11 equipped with the above-described rectangular steel pipe 21, first, the bottom plate 23 is welded and fixed to the bottom surface portion 31 of the rectangular steel pipe 21, and the reinforcing ribs 41 are fitted inside the rectangular steel pipe 21 and positioned in the installation location. Then, the peripheral edge of the reinforcing rib 41 is welded and fixed to the inner circumference of the rectangular steel pipe 21 through the window portion 39 of the side portion 35 of the rectangular steel pipe 21. Next, the end plate 37 is welded and fixed to the end of the rectangular steel pipe 21, and the sealing plate 43 is fastened and fixed to the side portion 35 of the rectangular steel pipe 21 with bolts. Furthermore, the support member 25 is fixed to the upper part of the rectangular steel pipe 21.

[0019] Subsequently, the upper surface of the support rail 29 of the support member 25, which will serve as the mounting surface for the linear motion guide device 13, is finished. Specifically, the upper surface of the support rail 29 is machined to create a flat surface. This upper surface of the support rail 29 may also be formed into a flat surface by grinding. It is preferable to machine or grind the upper surface of the square steel pipe 21, which will serve as the mounting surface for the support member 25, to make it a flat surface.

[0020] As shown in Figure 1, the linear motion guide device 13, which is attached to the support rail 29 of the support member 25, comprises a rail body 51 and a movable body 53.

[0021] The rail body 51 is fixed to the mounting surface which is the upper surface of the support rail 29 of the support member 25 provided on the upper part of the square steel pipe 21. The movable body 53 is fixed to the lower surface of the table 15. The movable body 53 is formed in a concave shape in cross-section, and is assembled to the rail body 51 with the concave portion fitted into the rail body 51.

[0022] The movable body 53, fixed to the table 15, has multiple rolling elements (not shown) rotatably held on the inner surface of a concave portion facing both sides of the rail body 51. The rolling elements allow for linear motion relative to the rail body 51 with low friction. As a result, the table 15 can move smoothly along the transport direction X by the linear motion guide device 13.

[0023] The drive unit 17 is equipped with a ball screw device consisting of a screw shaft 57 rotated by a drive motor 55 and a nut 59 fixed to the lower part of the table 15. The screw shaft 57 is positioned along the longitudinal direction of the square steel pipe 21 between the support rails 29 of the support member 25, and both ends are rotatably supported by bearings 58. The drive motor 55 has its rotation axis connected to one end of the screw shaft 57 and rotates the screw shaft 57. The drive unit 17 equipped with this ball screw device moves the nut 59 fixed to the table 15 along the screw shaft 57 by rotating the screw shaft 57 with the drive motor 55. As a result the table 15 supported by the linear motion guide device 13 moves, and the workpiece W placed on the table 15 is conveyed along the conveying direction X.

[0024] In the transport stage 100 configured in this way, as described above, the upper surface of the support rail 29 to which the rail body 51 of the linear motion guide device 13 is attached is finished to a flat surface by cutting or grinding in order to ensure accuracy.

[0025] Here, since the rectangular steel pipe 21 of the base 11 is long (for example, 7m), if reinforcing ribs 41 are not provided on this rectangular steel pipe 21, there is a risk that slight deformation such as bending may occur near the center in the longitudinal direction. Due to the effects of this deformation, it is conceivable that it will be difficult to machine the mounting surface, which is the upper surface of the support rail 29 etc. to which the rail body 51 of the linear motion guide device 13 is attached, to be a smooth surface with high precision.

[0026] According to the transport stage 100 of the first embodiment, the rigidity of the rectangular steel pipe 21 is increased by fixing the reinforcing ribs 41 inside the rectangular steel pipe 21. This suppresses the deflection of the rectangular steel pipe 21, allowing the mounting surface for the linear motion guide device 13 on the rectangular steel pipe 21 to be processed into a highly precise, smooth surface. This makes it possible to improve the transport accuracy of the table 15 supported by the linear motion guide device 13, and enable high-precision operation, while suppressing the increased cost that would result from creating a complex structure to increase strength.

[0027] In the example above, two reinforcing ribs 41 are shown installed on the square steel pipe 21. However, the number of reinforcing ribs 41 is not limited to two. Depending on the length of the square steel pipe 21, one reinforcing rib 41 may be installed, or three or more reinforcing ribs 41 may be installed.

[0028] Furthermore, the reinforcing ribs 41 installed inside the square steel pipe 21 may have other shapes. Figure 4 is a perspective view of the base 11 with reinforcing ribs 41A of a different shape. Figure 5 is a cross-sectional view of BB in Figure 4.

[0029] In the base 11 shown in Figures 4 and 5, a reinforcing rib 41A made of a plate material formed in an H shape in plan view is installed on the rectangular steel pipe 21. This reinforcing rib 41A has a width dimension smaller than the width dimension inside the rectangular steel pipe 21, and a pair of protrusions 42 are formed on the upper edge and lower edge, respectively. The protrusions 42 formed on the upper and lower edges are each formed closer to the sides of the reinforcing rib 41A.

[0030] The reinforcing rib 41A is welded and fixed to the inner circumference of the square steel pipe 21, with its protruding portion 42 positioned directly below the rail body 51 of the linear motion guide device 13, which is attached to the support rail 29 of the support member 25. With the base 11 equipped with the square steel pipe 21 on which the reinforcing rib 41A is installed, the area directly below the rail body 51 of the linear motion guide device 13 can be effectively reinforced by the reinforcing rib 41A.

[0031] Furthermore, the drive unit 17 provided on the transport stage 100 is not limited to one equipped with a ball screw device. Figure 6 is a perspective view of the transport stage 100 equipped with other drive units 17A.

[0032] The transport stage 100 shown in Figure 6 is equipped with a drive unit 17A consisting of a linear actuator. This drive unit 17A, consisting of a linear actuator, comprises a fixed rail 61 and a movable element 63. The fixed rail 61 is made of permanent magnets and is arranged along the longitudinal direction of the rectangular steel pipe 21 between the support rails 29 of the support member 25. The movable element 63 is a module having an electromagnetic coil and is fixed to the lower part of the table 15 and positioned with a gap between it and the fixed rail 61.

[0033] In this drive unit 17A, when an electromagnetic force is generated in the electromagnetic coil of the movable element 63, attractive and repulsive forces are generated between it and the fixed rail 61, which is made of a permanent magnet. These attractive and repulsive forces then become the moving force that moves the table 15, causing the table 15, supported by the linear motion guide device 13, to move, and the workpiece W placed on the table 15 to be transported along the transport direction X. The drive unit 17A, which is made of a linear actuator, may have the fixed rail 61 equipped with an electromagnetic coil and the movable element 63 made of a permanent magnet, or both the fixed rail 61 and the movable element 63 may be equipped with electromagnetic coils.

[0034] (Second Embodiment) Next, we will describe the transport stage according to the second embodiment. Note that components identical to those in the first embodiment described above are denoted by the same reference numerals and their descriptions are omitted. Figure 7 is a perspective view of the transport stage 200 according to the second embodiment. Figure 8 is a view taken along arrow C in Figure 7.

[0035] As shown in Figures 7 and 8, the transport stage 200 according to the second embodiment has a base 11 which includes a rectangular steel pipe 71 made of a steel pipe with a rectangular cross-section. When installed, the long side of this rectangular steel pipe 71 is the bottom surface 73 and the top surface 75, and the short side is the side surface 77. As a result, the rectangular steel pipe 71 has a wide shape with a large width dimension in cross-section.

[0036] On the upper part of this rectangular steel pipe 71, support rails 81 made of long flat plates are fixed at each installation position of the linear motion guide device 13, and the linear motion guide device 13 is directly attached to the upper surface of these support rails 81.

[0037] The rectangular steel pipe 71 has two reinforcing ribs 91 made of elongated plates inside. These reinforcing ribs 91 are arranged along the longitudinal direction of the rectangular steel pipe 71 and are spaced apart in the width direction of the rectangular steel pipe 71.

[0038] Figure 9 shows the state before the pair of reinforcing ribs 91 are inserted into the rectangular steel pipe 71. Figure 10 shows the state after the pair of reinforcing ribs 91 have been inserted into the rectangular steel pipe 71. As shown in Figures 7 to 10, the pair of reinforcing ribs 91 are inserted into the rectangular steel pipe 71 so as to be positioned directly below the rail body 51 of the linear motion guide device 13 which is attached to the support rail 81. Here, the bottom surface 73 and top surface 75 of the rectangular steel pipe 71 are provided with multiple through holes 73a and 75a at positions directly below the rail body 51, i.e., opposite the bottom and top surfaces of the pair of reinforcing ribs 91. The number and pitch of the multiple through holes 73a and 75a are determined considering strength, etc. The bottom and top surfaces of the pair of reinforcing ribs 91 are spot-welded to the bottom surface 73 and top surface 75 of the rectangular steel pipe 71 through these multiple through holes 73a and 75a. In other words, the reinforcing rib 91 is fixed directly below the location where the linear motion guide device 13 is installed in the width direction of the square steel pipe 71.

[0039] Thus, in the case of the transport stage 200 according to the second embodiment, the rigidity of the square steel pipe 71 is increased by fixing the reinforcing rib 91 inside the square steel pipe 71, thereby suppressing the deflection of the square steel pipe 71 and allowing the mounting surface of the linear motion guide device 13 on the square steel pipe 71 to be processed into a highly precise smooth surface.

[0040] In the transport stage 200, when the workpiece W is placed on the table 15 and transported, the load of the table 15 on which the workpiece W is placed is applied to the square steel pipe 71 of the base 11. At this time, as shown in Figure 11, in the case of a square steel pipe 71 without reinforcing ribs 91, deformation occurs such that the center of the upper surface 75 bends downward (see the dotted line in Figure 11), which may reduce the transport accuracy. In particular, this deformation is more likely to occur in the case of a wide square steel pipe 71 in cross-sectional view.

[0041] In contrast, in a rectangular steel pipe 71 in which reinforcing ribs 91 are arranged along the longitudinal direction and these reinforcing ribs 91 are fixed directly below the installation location of the linear motion guide device 13 in the width direction of the rectangular steel pipe 71, the load is supported by the reinforcing ribs 91 even when the workpiece W is loaded onto the table 15 and transported, and deformation of the rectangular steel pipe 71 is suppressed. As a result, displacement during transport is reduced and transport can be performed with high precision.

[0042] Furthermore, in the transport stage 200 according to the second embodiment, the drive unit 17 is not limited to a structure that includes a ball screw device. Figure 12 is a perspective view of the transport stage 200 equipped with other drive units 17A.

[0043] The transport stage 200 shown in Figure 12 is equipped with a drive unit 17A consisting of a linear actuator. The fixed rails 61 constituting the drive unit 17A are arranged along the longitudinal direction of the rectangular steel pipe 71 between support rails 81 provided on the upper part of the rectangular steel pipe 71.

[0044] In this drive unit 17A, the table 15 supported by the linear motion guide device 13 moves due to the attractive and repulsive forces generated between the movable element 63 and the fixed rail 61, and the workpiece W placed on the table 15 is transported along the transport direction X.

[0045] Thus, the present invention is not limited to the embodiments described above. It is also intended and within the scope of protection to be provided for the combination of each configuration of the embodiments, as well as for modifications and applications by those skilled in the art based on the description in the specification and well-known technology.

[0046] As described above, the following matters are disclosed in this specification: (1) Square steel pipe and A linear motion guide device provided on the aforementioned rectangular steel pipe, A table supported so as to be movable by the aforementioned linear motion guide device, A drive unit for moving the table, Equipped with, The aforementioned rectangular steel pipe has reinforcing ribs fixed inside, and the installation location of the linear motion guide device is reinforced by the reinforcing ribs, in a conveying stage. In this transport stage, reinforcing ribs are fixed inside a rectangular steel pipe that houses a linear motion guide device that movably supports the table, thereby reinforcing the installation location of the linear motion guide device. In this way, by fixing reinforcing ribs inside the square steel pipe, the rigidity of the square steel pipe is increased, thereby suppressing deflection of the square steel pipe and allowing the mounting surface of the linear motion guide device on the square steel pipe to be processed into a highly precise, smooth surface. This makes it possible to improve the transport accuracy of the table supported by the linear motion guide device and enable high-precision operation while suppressing the increased cost that would result from creating a complex structure to increase strength.

[0047] (2) The conveying stage according to (1), wherein the reinforcing ribs consist of plate material fixed along the width direction of the square steel pipe. With this configuration of the conveying stage, the rigidity of the square steel pipe can be easily increased by reinforcing ribs made of plate material fixed along the width direction of the square steel pipe.

[0048] (3) The conveying stage according to (1), wherein the reinforcing ribs are arranged along the longitudinal direction of the rectangular steel pipe and consist of plate material fixed directly below the installation location of the linear motion guide device in the width direction of the rectangular steel pipe. With this configuration of the conveying stage, the rigidity of the rectangular steel pipe can be easily increased along its longitudinal direction by reinforcing ribs made of plate material that are arranged and fixed along the longitudinal direction of the rectangular steel pipe. Furthermore, since the reinforcing ribs are fixed directly below the installation location of the linear motion guide device in the width direction of the square steel pipe, deformation of the square steel pipe is suppressed when a workpiece is loaded onto the table and transported, reducing displacement during transport and enabling high-precision transport.

[0049] (4) The transport stage according to any one of (1) to (3), wherein the drive unit is a ball screw device that moves a nut fixed to the table along the screw shaft by rotating the screw shaft with a drive motor. In this transport stage, the screw shaft is rotated by the drive motor, causing a nut fixed to the table to move along the screw shaft. This moves the table, which is supported by a linear motion guide device, and allows the workpiece placed on the table to be transported smoothly.

[0050] (5) The transport stage according to any one of (1) to (3), wherein the drive unit is a linear actuator having a fixed rail fixed to the rectangular steel pipe along its longitudinal direction and a movable element provided on the table, and generating a moving force for the movable element along the fixed rail by magnetic force. This transport stage uses magnetic force to generate a moving force in the movable element along a fixed rail, thereby moving the table supported by the linear motion guide device and smoothly transporting the workpiece placed on the table. [Explanation of Symbols]

[0051] 13 Linear motion guide device 15 tables 17,17A Drive Unit 21.71 Square steel pipe 41,91 Reinforcement Ribs 55 Drive motor 57 Screw shaft 59 Nut 61 Fixed Rail 63 Mover 100,200 transport stages

Claims

1. Rectangular steel pipe and A linear motion guide device provided on the aforementioned rectangular steel pipe, A table supported so as to be movable by the aforementioned linear motion guide device, A drive unit for moving the table, Equipped with, The aforementioned rectangular steel pipe has a bottom surface, a top surface, and side surfaces, with reinforcing ribs fixed inside, and the installation location of the linear motion guide device is reinforced by the reinforcing ribs. The reinforcing ribs are arranged along the longitudinal direction of the rectangular steel pipe and consist of plate members fixed directly below the installation location of the linear motion guide device in the width direction of the rectangular steel pipe. The bottom and top surfaces of the rectangular steel pipe are provided with a plurality of through holes at positions opposite to the lower and upper surfaces of the reinforcing ribs. The lower and upper surfaces of the reinforcing ribs are spot-welded to the bottom and upper surfaces of the rectangular steel pipe through the plurality of through holes. Transport stage.

2. Rectangular steel pipe and A linear motion guide device provided on the aforementioned rectangular steel pipe, A table supported so as to be movable by the aforementioned linear motion guide device, A drive unit for moving the table, Equipped with, The aforementioned rectangular steel pipe has a bottom surface, a top surface, and side surfaces, with reinforcing ribs fixed inside, and the installation location of the linear motion guide device is reinforced by the reinforcing ribs. The reinforcing rib consists of a plate fixed along the width direction of the rectangular steel pipe, and its peripheral edge is welded and fixed to the inner circumference of the rectangular steel pipe. The side surface of the rectangular steel pipe is provided with a window portion at a position away from the installation position of the reinforcing rib for welding the reinforcing rib. Transport stage.

3. The aforementioned rectangular steel pipe consists of a steel pipe with a rectangular cross-section. The transport stage according to claim 1 or 2.

4. The drive unit is a ball screw device that moves a nut fixed to the table along the screw shaft by rotating the screw shaft with a drive motor. The transport stage according to claim 1.

5. The drive unit is a linear actuator comprising a fixed rail fixed to the rectangular steel pipe along its longitudinal direction and a movable element provided on the table, and generating a moving force along the fixed rail on the movable element by magnetic force. The transport stage according to claim 1.

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