Lifting device

Abstract

To enable a guide part to smoothly follow an inclined surface generated on a vertical guide surface in a lifting device having the guide part that is attached to a lifting part and that guides upward and downward movement of the lifting part in a state of being in contact with a vertical guide surface.SOLUTION: A lifting device comprises a lifting table 4 that can be raised and lowered and a guide part 5 that is attached to the lifting table 4 and guides upward and downward movement of the lifting table 4 in a state of being in contact with a guide surface 3a, wherein the guide part 5 includes: a fixed part 5a fixed to the lift table 4; a tilting plate 5d pivotably supported on the fixed part 5a; a guide roller 5e rotatably attached to the tilting plate 5d and in contact with the guide surface 3a; and an energizing part 5f that energizes the tilting plate 5d toward the guide surface 3a.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a lifting device. [Background technology]

[0002] In facilities where industrial machinery and the like are installed, an elevator device for transporting articles in the vertical direction is installed. For example, Patent Document 1 discloses a stacker crane, which is an elevator device used in automated warehouses. The stacker crane disclosed in Patent Document 1 includes a pair of masts, a platform that is raised and lowered between the masts, and guide rollers that abut against the surfaces of the masts. In such a stacker crane, the guide rollers rotate while abutting against the surfaces of the masts, so that the platform is guided along the masts as it is raised and lowered. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-142917 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the masts of the stacker crane disclosed in Patent Document 1 are several tens of meters high. This makes it difficult to make the distance between a pair of masts (hereinafter referred to as the inter-mast distance) uniform in the vertical direction. Patent Document 1 discloses a structure in which the guide rollers are supported by coil springs with horizontally disposed axes to absorb such changes in the distance between the masts in the vertical direction.

[0005] The configuration disclosed in Patent Document 1 moves the guide roller in a direction perpendicular to the vertical guide surface of the mast (the surface of the mast) (a direction along the axis of the coil spring). In Patent Document 1, when the guide roller support section tilts due to the reaction force that the guide roller receives from the vertical guide surface during lifting and lowering of the loading platform, the coil spring bends. When the coil spring bends, the coil spring does not expand and contract smoothly, making it difficult to smoothly move the guide roller so as to follow the horizontal position change of the vertical guide surface.

[0006] Furthermore, this type of problem does not only occur with stacker cranes, but occurs with all lifting devices that have a lifting section such as a loading platform and a guide section that is attached to the lifting section and abuts against a vertical guide surface to guide the lifting and lowering of the lifting section.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to enable a lifting device having a guide part that is attached to a lifting part and abuts a vertical guide surface to guide the lifting and lowering of the lifting part, so that the guide part can smoothly follow changes in the horizontal position of the vertical guide surface. [Means for solving the problem]

[0008] The present invention employs the following configuration as a means for solving the above problems.

[0009] A first aspect of the present invention is a lifting device comprising a lifting section that can be raised and lowered, and a guide section that is attached to the lifting section and abuts against a vertical guide surface to guide the lifting and lowering of the lifting section, wherein the guide section comprises a fixed section that is fixed to the lifting section, a tilting section that is pivotally supported on the fixed section so that it can tilt, a guide roller that is rotatably attached to the tilting section and abuts against the vertical guide surface, and a biasing section that biases the tilting section toward the vertical guide surface.

[0010] A second aspect of the present invention is the same as the first aspect, in that the biasing portion comprises a rod rotatably connected to the tilting portion and supported axially movably relative to the fixed portion, and an elastic body that biases the rod toward the tilting portion.

[0011] A third aspect of the present invention is the second aspect, and employs a configuration in which the rod is supported tiltably relative to the fixed portion.

[0012] A fourth aspect of the present invention is the third aspect, wherein the biasing portion comprises a biasing portion rotation shaft journaled relative to the fixed portion, and a bush fixed to the biasing portion rotation shaft and supporting the rod axially slidably.

[0013] A fifth aspect of the present invention employs a configuration in which, in any one of the second to fourth aspects, the guide roller is arranged between the connection position of the tilting portion and the fixed portion and the connection position of the rod and the tilting portion.

[0014] A sixth aspect of the present invention is any one of the first to fifth aspects, and is configured to include a travelling carriage section, a mast erected on the carriage section and having the vertical guide surface, and an elevation drive section that raises and lowers the elevation section. [Effects of the Invention]

[0015] According to the present invention, a tilting section is provided that is tiltable relative to a fixed section fixed to the lifting section, and a guide roller is attached to the tilting section. Furthermore, according to the present invention, the tilting section is biased toward the vertical guide surface by a biasing section. Therefore, when the vertical guide surface is displaced, the tilting section tilts relative to the fixed section while the guide roller remains in contact with the vertical guide surface, thereby absorbing the horizontal positional change of the vertical guide surface. This prevents a reaction force that would cause the biasing section to bend, allowing the guide roller to smoothly follow the vertical guide surface. Therefore, according to the present invention, in a lifting device having a guide section that is attached to the lifting section and abuts the vertical guide surface to guide the lifting section, the guide section can smoothly follow the horizontal positional change of the vertical guide surface. [Brief explanation of the drawings]

[0016] [Figure 1] 1A and 1B are schematic diagrams showing the general configuration of a stacker crane according to a first embodiment of the present invention, in which (a) is a side view and (b) is a top view. [Figure 2] 2 is a schematic side view of a guide portion provided in the stacker crane in the first embodiment of the present invention. FIG. [Figure 3] 3 is a cross-sectional view taken along the line AA in FIG. 2. [Figure 4] 3 is a cross-sectional view of FIG. 2 taken along line B-B. [Figure 5] 3 is a cross-sectional view taken along CC in FIG. 2. [Figure 6] 1A and 1B are overall views of a fixed part provided on a stacker crane in a first embodiment of the present invention, in which (a) is a side view, (b) is a front view seen from the direction of arrow A in (a), and (c) is a plan view seen from the direction of arrow B in (a). [Figure 7] 4 is an explanatory view showing an operation state in which a guide portion abuts against a guide surface positioned forward of a reference surface in the stacker crane according to the first embodiment of the present invention. FIG. [Figure 8]4 is an explanatory view showing an operation state in which a guide portion abuts against a guide surface positioned rearward of a reference surface in the stacker crane according to the first embodiment of the present invention. FIG. [Figure 9] FIG. 10 is a schematic side view of a guide portion provided in a stacker crane according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a plan view of a fixing portion provided on a stacker crane according to a second embodiment of the present invention. [Figure 11] FIG. 10 is a side view schematically showing the general configuration of a stacker crane according to a third embodiment of the present invention. [Figure 12] 10 is an explanatory view showing a state in which the guide portion abuts against a guide surface positioned parallel to the front of the reference surface; FIG. [Figure 13] 10 is an explanatory view showing an operation state in which the guide portion abuts against a guide surface positioned parallel to the rear of the reference surface; FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of a lifting device according to the present invention will be described with reference to the drawings.

[0018] (First embodiment) 1 is a schematic diagram showing the general configuration of a stacker crane 1 (lifting device) of this embodiment, where (a) is a side view and (b) is a top view. In this embodiment, the stacker crane 1 will be described as an example of a lifting device. However, the lifting device is not limited to the stacker crane 1. The lifting device may also be a vertical conveyor or a lift device.

[0019] The stacker crane 1 of this embodiment is installed in an automated warehouse and transports articles vertically and horizontally inside the automated warehouse. For example, the stacker crane 1 transports articles between an in-and-out device that takes articles in and out of the automated warehouse and a storage section of a rack that stores the articles. The stacker crane 1 also transports articles stored in a rack to another storage section of the rack. As shown in FIG. 1 , this stacker crane 1 includes a carriage section 2, a mast 3, a lifting platform 4 (lifting section), a guide section 5, a lifting drive section 6, and a transfer device 7.

[0020] The cart unit 2 can travel along rails (not shown) laid on the floor of the automated warehouse. The cart unit 2 is equipped with a travel motor (not shown) and travels horizontally using the power generated by the travel motor. The cart unit 2 directly or indirectly supports the mast 3, lifting platform 4, guide unit 5, lifting drive unit 6, and transfer device 7.

[0021] The masts 3 are erected relative to the bogie section 2. In this embodiment, two masts 3 are provided. These masts 3 are arranged at a distance from each other in the traveling direction of the bogie section 2. Each mast 3 is formed in a rectangular shape in a plan view. In other words, the masts 3 are formed in the shape of a prism having four sides. These masts 3 have the same vertical dimension. For example, each mast 3 is formed so that its vertical dimension is several tens of meters.

[0022] The masts 3 are arranged so that one of their four side surfaces faces each other in parallel. The side of each mast 3 that faces the other mast 3 is used as a guide surface 3a (vertical guide surface) for guiding the elevation of the platform 4. In other words, the masts 3 are arranged so that the guide surfaces 3a face each other in parallel. These guide surfaces 3a are vertical surfaces with their normal direction being horizontal. The upper ends of the masts 3 are connected to each other by an upper frame. This upper frame is omitted in Figure 1(b).

[0023] The lifting platform 4 is disposed between one mast 3 and the other mast 3. This lifting platform 4 can be raised and lowered between the one mast 3 and the other mast 3 by a lifting drive unit 6. When this lifting platform 4 is raised and lowered, it is guided along the guide surface 3a of the mast 3 by a guide unit 5. The lifting platform 4 supports the transfer device 7 from below. In other words, the transfer device 7 is raised and lowered together with the lifting platform 4.

[0024] The guide units 5 are attached to the edge of the lifting platform 4. In this embodiment, one guide unit 5 is provided on one edge of the lifting platform 4 on the mast 3 side, and another guide unit 5 is provided on the edge of the lifting platform 4 on the other mast 3 side. In this embodiment, two guide units 5 are provided with the transfer device 7 sandwiched between them in a plan view. These guide units 5 are arranged along the arrangement direction of the masts 3 (i.e., the traveling direction of the carriage unit 2).

[0025] Here, the detailed structure of the guide section 5 will be described with reference to Figs. 2 to 6. In this embodiment, the two guide sections 5 are provided in a symmetrical shape in the horizontal direction with the transfer device 7 at the center. Therefore, Figs. 2 to 6 illustrate and describe one of the two guide sections 5. As will be described later, the two guide sections may have different structures.

[0026] As described above, the guide unit 5 is attached to the lifting platform 4, and guides the lifting and lowering of the lifting platform 4 while abutting against the guide surface 3a of the mast 3. Fig. 2 is a schematic side view of the guide unit 5. Fig. 3 is a cross-sectional view taken along line AA in Fig. 2. Fig. 4 is a cross-sectional view taken along line BB in Fig. 2. Fig. 5 is a cross-sectional view taken along line CC in Fig. 2.

[0027] In the following description, for convenience of explanation, the normal direction to the guide surface 3a of the mast 3 will be referred to as the front-rear direction, and the horizontal direction perpendicular to the front-rear direction will be referred to as the left-right direction. The direction perpendicular to the front-rear direction and the left-right direction is the up-down direction.

[0028] As shown in FIG. 2, the guide portion 5 includes a fixed portion 5a, a sliding bearing 5b for connecting the tilting plate, a rotating shaft 5c for connecting the tilting plate, a tilting plate 5d (tilting portion), a guide roller 5e, and a biasing portion 5f.

[0029] The fixed part 5a is a part that is fixed to the lifting platform 4. Figure 6 shows an overall view of the fixed part 5a, with (a) being a side view, (b) being a front view seen from the direction of arrow A in (a), and (c) being a plan view seen from the direction of arrow B in (a). As shown in these figures, the fixed part 5a has a base plate 5a1, a right arm part 5a2, and a left arm part 5a3.

[0030] The base plate 5a1 is a plate-like portion fixed to the lifting platform 4. The base plate 5a1 is fixed to the lifting platform 4 with bolts (not shown). The right arm portion 5a2 and the left arm portion 5a3 are plate-like portions erected on the base plate 5a1 and are spaced apart in the left-right direction. The right arm portion 5a2 is located to the right of the left arm portion 5a3. The left arm portion 5a3 is located to the left of the right arm portion 5a2.

[0031] The right arm portion 5a2 and the left arm portion 5a3 are formed to have the same external shape. The right arm portion 5a2 and the left arm portion 5a3 each have a lower portion 5a4, an inclined portion 5a5, and an upper portion 5a6. The lower portion 5a4 is connected to the base plate 5a1. The inclined portion 5a5 extends from the upper portion of the lower portion 5a4 at an angle upward toward the mast 3 (forward). The upper portion 5a6 extends horizontally from the upper portion of the inclined portion 5a5 in a direction toward the mast 3.

[0032] The right arm portion 5a2 and the left arm portion 5a3 have a fitting hole 5a7 in their lower portion 5a4 into which a rod base connecting plain bearing 16 of the biasing portion 5f, which will be described later, is fitted. In addition, the right arm portion 5a2 and the left arm portion 5a3 have a fitting hole 5a8 in their upper portion 5a6 into which a tilt plate connecting plain bearing 5b is fitted.

[0033] As shown in Fig. 4, the tilt plate connecting plain bearing 5b is fitted into a fitting hole 5a8 provided in the upper part 5a6 of the fixed part 5a. In this embodiment, two tilt plate connecting plain bearings 5b are provided. One tilt plate connecting plain bearing 5b is fitted into a fitting hole 5a8 provided in the upper part 5a6 of the right arm part 5a2. The other tilt plate connecting plain bearing 5b is fitted into a fitting hole 5a8 provided in the upper part 5a6 of the left arm part 5a3. These tilt plate connecting plain bearings 5b rotatably support the tilt plate connecting rotation shaft 5c.

[0034] As shown in FIG. 4, the tilt plate connecting rotation shaft 5c is a shaft portion rotatably supported by two tilt plate connecting sliding bearings 5b. This tilt plate connecting rotation shaft 5c is supported rotatably around an axis L1 along the left-right direction. A tilt plate 5d is fixed to one end of this tilt plate connecting rotation shaft 5c. In this embodiment, two tilt plates 5d are provided. One tilt plate 5d is fixed to one end of the tilt plate connecting rotation shaft 5c, and the other tilt plate 5d is fixed to the other end of the tilt plate connecting rotation shaft 5c. The tilt plate 5d is fixed to the tilt plate 5d by fastening it with bolts (not shown).

[0035] The tilting plate 5d is a plate-like member pivotally supported on the fixed portion 5a so as to be tiltable. In this embodiment, two tilting plates 5d are provided as described above. As shown in FIG. 2, the tilting plates 5d are provided to extend in the vertical direction.

[0036] The upper end of each tilt plate 5d is fixed to a tilt-plate-connecting rotation shaft 5c. This tilt-plate-connecting rotation shaft 5c is rotatably connected to the fixed part 5a via a tilt-plate-connecting plain bearing 5b. Therefore, the tilt plate 5d is journaled to the fixed part 5a via the tilt-plate-connecting rotation shaft 5c and the tilt-plate-connecting plain bearing 5b. In other words, the tilt plate 5d is tiltable relative to the fixed part 5a around the axis L1 of the tilt-plate-connecting rotation shaft 5c.

[0037] The lower end of each tilting plate 5d is connected to a biasing portion 5f. As will be described later, the biasing portion 5f biases the tilting plate 5d toward the mast 3. Therefore, the lower end of each tilting plate 5d is always pressed toward the guide surface 3a of the mast 3.

[0038] The guide roller 5e is a member rotatably connected to the tilt plate 5d and abuts against the guide surface 3a of the mast 3. As shown in FIG. 5, the guide roller 5e has a shaft portion 5e1, a ball bearing 5e2, and a roller portion 5e3. The shaft portion 5e1 is fixed to the tilt plate 5d and is a cylindrical member with its axis oriented in the left-right direction. One end of the shaft portion 5e1 is fixed to one tilt plate 5d, and the other end of the shaft portion 5e1 is fixed to the other tilt plate 5d.

[0039] The ball bearing 5e2 is interposed between the shaft portion 5e1 and the roller portion 5e3, and rotatably connects the roller portion 5e3 to the shaft portion 5e1. The roller portion 5e3 is made of, for example, resin, and its peripheral surface abuts against the guide surface 3a of the mast 3. The roller portion 5e3 is rotatable about the axis L2 of the shaft portion 5e1, which extends in the left-right direction.

[0040] 2, the guide roller 5e is disposed in the vertical center of the tilting plate 5d. That is, in this embodiment, the guide roller 5e is disposed between the upper end of the tilting plate 5d connected to the fixed portion 5a and the lower end of the tilting plate 5d connected to the biasing portion 5f.

[0041] The biasing portion 5f is a component that biases the tilting plate 5d toward the guide surface 3a of the mast 3. As shown in Figures 2 and 3, the biasing portion 5f includes a rod tip connection rotating shaft 10, a rod tip connection plain bearing 11, a rod 12, a coil spring 13 (elastic body), a bush 14, a rod base connection rotating shaft 15 (biasing portion rotating shaft), and a rod base connection plain bearing 16. Note that in Figure 2, the portion including the bush 14 and the rod base connection rotating shaft 15 is shown in cross section for ease of explanation.

[0042] As shown in Fig. 3, the rod tip connection rotating shaft 10 is a shaft provided to connect the lower ends of the two tilt plates 5d. The rod tip connection rotating shaft 10 is formed in a cylindrical shape with an axis L3 aligned in the left-right direction. One end of the rod tip connection rotating shaft 10 is fixed to one of the tilt plates 5d, and the other end of the rod tip connection rotating shaft 10 is fixed to the other tilt plate 5d. The rod tip connection rotating shaft 10 is fixed to the tilt plates 5d by being fastened to the lower ends of the tilt plates 5d with bolts.

[0043] The rod tip portion connecting sliding bearing 11 is a bearing interposed between the rod tip portion connecting rotating shaft 10 and the tip of the rod 12. This rod tip portion connecting sliding bearing 11 connects the rod tip portion connecting rotating shaft 10 and the rod 12 so that the tip of the rod 12 can rotate around the axis L3 of the rod tip portion connecting rotating shaft 10 relative to the rod tip portion connecting rotating shaft 10.

[0044] The rod 12 is a rod-shaped member extending in the front-rear direction. The rod 12 is disposed so that its axis L4 is aligned with the front-rear direction. A through-hole 12b is provided in the tip 12a of the rod 12 (the end of the rod 12 on the mast 3 side), through which the rod tip connecting rotary shaft 10 is inserted. The through-hole 12b passes through the tip 12a of the rod 12 in the left-right direction. The tip 12a of the rod 12 is larger than the portion of the rod 12 excluding the tip 12a (base 12c) when viewed from the front-rear direction. The rear surface of the tip 12a is used as a receiving surface 12d of the coil spring 13.

[0045] The coil spring 13 is disposed between the tip 12a of the rod 12 and the bush 14, and is disposed so as to surround the base 12c of the tip 12a of the rod 12 from above, below, left, and right. In other words, the base 12c of the rod 12 is inserted through the coil spring 13. One end of the coil spring 13 in the front-to-rear direction abuts against the receiving surface 12d of the tip 12a of the rod 12 from behind. The other end of the coil spring 13 in the front-to-rear direction abuts against the bush 14 from the front.

[0046] Such a coil spring 13 is disposed between the tip 12a of the rod 12 and the bushing 14 in a state compressed in the front-to-rear direction. Therefore, the tip 12a of the rod 12 is urged toward the guide surface 3a of the mast 3 by the restoring force of the coil spring 13. Furthermore, the lower end of the tilting plate 5d connected to the tip 12a of the rod 12 is also urged toward the guide surface 3a of the mast 3 by the restoring force of the coil spring 13, similar to the tip 12a of the rod 12.

[0047] The bushing 14 is fixed to the rod tip connection rotating shaft 10 and supports the base 12c of the rod 12 so that it can slide in the front-rear direction. In other words, the bushing 14 is fixed to the rod tip connection rotating shaft 10 and supports the rod 12 so that it can slide in the direction of the axis L4. A flange is provided at the front end of the bushing 14. The end of the coil spring 13 abuts against the front surface of this flange.

[0048] The rod base connection rotating shaft 15 is a member that is journaled on the fixed part 5a via a rod base connection sliding bearing 16. The rod base connection sliding bearing 16 is supported rotatably about an axis L5 that extends in the left-right direction. The rod base connection rotating shaft 15 is provided with a through hole 15a that penetrates in the front-rear direction. A bush 14 is fitted into this through hole 15a. The rod base connection rotating shaft 15 supports the rod 12 via the bush 14.

[0049] The rod 12 supported by such a rod base connection rotating shaft 15 can also rotate about the axis L5 as a result of the rotation of the rod base connection rotating shaft 15 about the axis L5. In other words, the rod 12 can rotate by moving the tip end 12a up and down.

[0050] Two rod base connection sliding bearings 16 are provided. One of the rod base connection sliding bearings 16 is fitted into a fitting hole 5a7 provided in the lower part 5a4 of the right arm part 5a2 of the fixed part 5a. The other rod base connection sliding bearing 16 is provided to fit into a fitting hole 5a7 provided in the lower part 5a4 of the left arm part 5a3 of the fixed part 5a. As described above, these rod base connection sliding bearings 16 support the rod base connection rotating shaft 15 so that it can rotate about the axis L5.

[0051] Returning to Fig. 1, the lifting drive unit 6 is a drive unit for raising and lowering the lifting platform 4. This lifting drive unit 6 includes, for example, a motor fixed to the carriage unit 2, and a wire that is wound up or let out by the power of the motor and is connected to the lifting platform 4 from above via the upper end of the mast 3. In this type of lifting drive unit 6, the motor is driven to wind up or let out the wire, thereby raising and lowering the lifting platform 4.

[0052] The transfer device 7 is installed on the lifting platform 4 and moves the article in the left-right direction. The article is moved left-right by the transfer device 7, and thereby moved between the transfer device 7 and the destination (for example, a storage / retrieval device or a storage section of a rack).

[0053] Next, the lifting and lowering operation of the lifting platform 4 in the stacker crane 1 of this embodiment configured as described above will be described with reference to FIGS.

[0054] Under the control of a control device (not shown), the lifting platform 4 is raised and lowered by the lifting drive unit 6. At this time, the lifting platform 4 is raised and lowered along the guide surfaces 3a of the masts 3 by the guide units 5. As described above, the height of the masts 3 is several tens of meters, so it is difficult to make the distance between the two masts 3 (the inter-mast distance) uniform in the vertical direction. If the inter-mast distance changes in the vertical position, the guide surfaces 3a of the masts 3 that the guide units 5 abut against may become inclined, or the position of the guide surfaces 3a may be displaced horizontally. As a result, the guide surfaces 3a of the masts 3 may have inclined surfaces 3a1.

[0055] In the following description, the guide surface 3a, which is vertical at a pre-designed position, is referred to as the reference plane M. FIG. 7 is an explanatory diagram showing the operation of the guide unit 5 when it abuts against the guide surface 3a (inclined surface 3a1) located forward of the reference plane. The lower end of the tilting plate 5d is biased toward the mast 3 by the restoring force of the coil spring 13 of the biasing unit 5f. Therefore, as shown in FIG. 7, when the inclined surface 3a1 is located forward of the reference plane M, the tilting plate 5d tilts so that its lower end is located forward of its upper end.

[0056] In this way, by tilting the tilting plate 5d so that the lower end is positioned forward of the upper end, the circumferential surface of the roller portion 5e3 is always in contact with the guide surface 3a. In other words, in the stacker crane 1 of this embodiment, when the guide surface 3a is positioned forward of the reference plane, the guide roller 5e can be moved to follow the guide surface 3a with the circumferential surface of the roller portion 5e3 always in contact with the guide surface 3a.

[0057] 8 is an explanatory diagram illustrating the operation of the guide portion 5 when it abuts against the inclined surface 3a1 located rearward of the reference plane M. The lower end of the tilting plate 5d is biased toward the mast 3 by the restoring force of the coil spring 13 of the biasing portion 5f. Therefore, as shown in FIG. 8, when the inclined surface 3a1 is located rearward of the reference plane M, the tilting plate 5d tilts so that the lower end is located rearward of the upper end.

[0058] In this way, by tilting the tilting plate 5d so that the lower end is positioned rearward of the upper end, the circumferential surface of the roller portion 5e3 is always in contact with the guide surface 3a. In other words, in the stacker crane 1 of this embodiment, when the guide surface 3a is positioned rearward of the reference plane M, the guide roller 5e can be moved to follow the guide surface 3a with the circumferential surface of the roller portion 5e3 always in contact with the guide surface 3a.

[0059] In this way, according to the stacker crane 1 of this embodiment, even when the guide surface 3a has an inclined surface 3a1, the guide roller 5e can be made to always follow the guide surface 3a.

[0060] The stacker crane 1 of this embodiment as described above comprises a lifting platform 4 and a guide unit 5. The lifting platform 4 is capable of moving up and down. The guide unit 5 is attached to the lifting platform 4 and contacts the guide surface 3a to guide the lifting platform 4 as it moves up and down. The guide unit 5 also comprises a fixed unit 5a, a tilting plate 5d, a guide roller 5e, and a biasing unit 5f. The fixed unit 5a is fixed to the lifting platform 4. The tilting plate 5d is pivotally supported by the fixed unit 5a so that it can tilt. The guide roller 5e is rotatably attached to the tilting plate 5d and contacts the guide surface 3a. The biasing unit 5f biases the tilting plate 5d toward the guide surface 3a.

[0061] The stacker crane 1 of this embodiment is provided with a tilting plate 5d that can tilt relative to a fixed portion 5a fixed to the lifting platform 4, and a guide roller 5e is attached to the tilting plate 5d. Furthermore, the stacker crane 1 of this embodiment is biased toward the guide surface 3a by the biasing portion 5f. Therefore, if the inter-mast dimension changes and the horizontal position of the guide surface 3a changes, the tilting plate 5d tilts relative to the fixed portion 5a while the guide roller 5e remains in contact with the guide surface 3a, thereby absorbing the horizontal position change of the guide surface 3a. This prevents a reaction force that would bend the coil spring 13 of the biasing portion 5f from acting, allowing the guide roller 5e to follow the guide surface 3a. Therefore, the stacker crane 1 of this embodiment, when equipped with a guide portion 5 that is attached to the lifting platform 4 and abuts against the guide surface 3a to guide the lifting and lowering of the lifting platform 4, allows the guide portion 5 to smoothly follow the horizontal position change of the guide surface 3a.

[0062] In the stacker crane 1 of this embodiment, the biasing portion 5f includes a rod 12 and a coil spring 13. The rod 12 is rotatably connected to the tilting plate 5d and supported by the fixed portion 5a so as to be movable in the axial direction. The coil spring 13 biases the rod 12 toward the tilting plate 5d.

[0063] According to the stacker crane 1 of this embodiment, the rod 12 is supported so as to be movable in the direction along the axis L4 relative to the fixed part 5a. This makes it possible to change the position of the rod 12 in the direction along the axis L4 in accordance with the tilting movement of the tilting plate 5d relative to the fixed part 5a. This prevents the rod 12 from interfering with the tilting movement of the tilting plate 5d relative to the fixed part 5a.

[0064] Furthermore, in the stacker crane 1 of this embodiment, the rod 12 is supported so as to be tiltable relative to the fixed part 5a. This makes it possible to change the attitude of the rod 12 in the rotation direction about the axis L5 in accordance with the tilting movement of the tilting plate 5d relative to the fixed part 5a. This prevents the rod 12 from interfering with the tilting movement of the tilting plate 5d relative to the fixed part 5a.

[0065] Furthermore, in the stacker crane 1 of this embodiment, the biasing portion 5f includes a rod base connecting rotating shaft 15 journaled to the fixed portion 5a, and a bushing 14 fixed to the rod base connecting rotating shaft 15 and supporting the rod 12 axially slidably. According to the stacker crane 1 of this embodiment, the rod 12 can be made slidable and tiltable relative to the fixed portion 5a with a simple structure.

[0066] Furthermore, in the stacker crane 1 of this embodiment, a guide roller 5e is disposed between the connection position of the tilting plate 5d and the fixed part 5a and the connection position of the rod 12 and the tilting plate 5d. This configuration ensures a long distance from the connection position of the tilting plate 5d and the fixed part 5a, which serves as the fulcrum of the tilting plate 5d, to the connection position of the rod 12 and the tilting plate 5d, which serves as the point of force on the tilting plate 5d. This makes it possible to reduce the biasing force of the coil spring 13.

[0067] The stacker crane 1 of this embodiment comprises a travellable carriage section 2, a mast 3 erected on the carriage section 2 and having a guide surface 3a, and an elevation drive section 6 that raises and lowers the elevation platform 4. Therefore, the stacker crane 1 of this embodiment can be used as a stacker crane for use in automated warehouses and the like.

[0068] (Second embodiment) Next, a second embodiment of the present invention will be described with reference to Figures 9 and 10. Note that in this embodiment, the description of the same parts as those in the first embodiment will be omitted or simplified.

[0069] 9 is a schematic side view of a guide unit 5A provided in a stacker crane of this embodiment. As shown in this figure, the guide unit 5A of this embodiment includes a fixed unit 5g instead of the fixed unit 5a of the first embodiment, and also includes a tilting plate 5h instead of the tilting plate 5d of the first embodiment.

[0070] The fixed portion 5g is a portion that is fixed to the lift platform 4. Fig. 10 is a plan view of the fixed portion 5g. As shown in Fig. 10, the fixed portion 5g has a base plate 5g1, a right arm portion 5g2, and a left arm portion 5g3.

[0071] The base plate 5g1 is a plate-like portion fixed to the lifting platform 4. The base plate 5g1 is fixed to the lifting platform 4 with bolts (not shown). The right arm portion 5g2 and the left arm portion 5g3 are plate-like portions erected on the base plate 5g1 and are spaced apart in the left-right direction. The right arm portion 5g2 is located to the right of the left arm portion 5g3. The left arm portion 5g3 is located to the left of the right arm portion 5g2.

[0072] The right arm 5g2 and the left arm 5g3 are formed to have the same external shape. The right arm 5g2 and the left arm 5g3 each have a base 5g4 and a protruding portion 5g5. The base 5g4 is connected to the base plate 5g1 and extends in the vertical direction. The protruding portion 5g5 protrudes from the vertical center of the base 5g4 in a direction approaching the mast 3 (forward).

[0073] The right arm portion 5g2 and the left arm portion 5g3 have a fitting hole 5g6 formed in the upper part of the base portion 5g4, into which the rod base connecting plain bearing 16 of the biasing portion 5f fits. In addition, the right arm portion 5g2 and the left arm portion 5g3 have a fitting hole 5g7 formed in the protrusion 5g5, into which the tilt plate connecting plain bearing 5b fits.

[0074] The tilting plate 5h is a plate-like member pivotally supported by the fixed portion 5g so as to be tiltable. In this embodiment, similar to the tilting plate 5d in the first embodiment, two tilting plates 5h of the same shape are provided, aligned in the left-right direction. As shown in FIG. 9, these tilting plates 5h are provided extending in the up-down direction.

[0075] The vertical center of each tilt plate 5h is fixed to a tilt-plate-connecting rotation shaft 5c. This tilt-plate-connecting rotation shaft 5c is rotatably connected to a fixed part 5g via a tilt-plate-connecting plain bearing 5b. Therefore, the tilt plate 5h is journaled to the fixed part 5g via the tilt-plate-connecting rotation shaft 5c and the tilt-plate-connecting plain bearing 5b. In other words, the tilt plate 5h is tiltable relative to the fixed part 5g around the axis L1 of the tilt-plate-connecting rotation shaft 5c.

[0076] The upper end of each tilting plate 5h is connected to a biasing portion 5f. The biasing portion 5f biases the tilting plate 5h toward the mast 3. Therefore, the upper end of each tilting plate 5h is always pressed against the guide surface 3a of the mast 3.

[0077] 9, in this embodiment, the guide roller 5e is disposed at the lower end of the tilt plate 5h. That is, in this embodiment, the guide roller 5e is disposed below the center of the tilt plate 5h connected to the fixed portion 5g and the upper end of the tilt plate 5h connected to the biasing portion 5f.

[0078] In this embodiment, the rod tip connection rotating shaft 10 is fixed to the tilt plate 5h by being fastened to the upper end of the tilt plate 5h with bolts. One of the two rod base connection sliding bearings 16 is fitted into a fitting hole 5g6 provided in the upper end of the base 5g4 of the right arm 5g2 of the fixed part 5g. The other of the two rod base connection sliding bearings 16 is arranged to fit into a fitting hole 5g6 provided in the upper end of the base 5g4 of the left arm 5g3 of the fixed part 5g.

[0079] In the stacker crane of this embodiment, the lower end of the tilting plate 5h is biased toward the mast 3 by the restoring force of the coil spring 13 of the biasing portion 5f. Therefore, when the guide surface 3a is positioned rearward of the reference plane M, the tilting plate 5h tilts so that the lower end is positioned rearward of the upper end.

[0080] In this way, by tilting the tilting plate 5h so that the lower end is positioned rearward of the upper end, the circumferential surface of the roller portion 5e3 is always in contact with the guide surface 3a. In other words, in the stacker crane 1 of this embodiment, when the guide surface 3a is positioned rearward of the reference plane M, the guide roller 5e can be moved to follow the guide surface 3a with the circumferential surface of the roller portion 5e3 always in contact with the guide surface 3a.

[0081] Also, even when the guide surface 3a is positioned forward of the reference plane M, the tilting plate 5h tilts so that the upper end is positioned rearward of the lower end, so that the peripheral surface of the roller portion 5e3 is always in contact with the guide surface 3a.

[0082] In this way, in the stacker crane of this embodiment as well, the guide rollers 5e can be made to always follow the guide surfaces 3a even if the distance between the masts changes. Therefore, in the stacker crane of this embodiment as well, when the stacker crane has a guide part 5 that is attached to the lifting platform 4 and that guides the lifting and lowering of the lifting platform 4 while abutting against the guide surfaces 3a, the guide part 5 can be made to smoothly follow the guide surfaces 3a.

[0083] (Third embodiment) Next, a third embodiment of the present invention will be described with reference to Fig. 11. Note that in this embodiment, the description of the same parts as those in the first embodiment will be omitted or simplified.

[0084] 11 is a side view showing a schematic configuration of a stacker crane 1A (lifting device) of this embodiment. As shown in this figure, the stacker crane 1A of this embodiment is provided with a fixed guide unit 8 instead of one of the guide units 5 provided on both sides of the lifting platform 4 in the first embodiment.

[0085] This fixed guide unit 8 does not have a tilting plate 5d or a biasing unit 5f like the guide unit 5, and has a configuration in which the guide roller 5e is directly installed on the lifting platform 4. In other words, in the stacker crane 1A of this embodiment, changes in the inter-mast dimension are absorbed by the guide unit 5 arranged on one side of the lifting platform 4. Therefore, with the stacker crane 1 of this embodiment, the inclination of the guide surface 3a of the mast 3 is absorbed on only one side of the lifting platform 4, and it becomes possible to accurately position the lifting platform 4 using the fixed guide unit 8 side as a reference.

[0086] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the above-described embodiments. The shapes and combinations of the components shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0087] For example, in the above embodiment, a configuration in which only one biasing portion 5f is provided on the guide portion 5 has been described. However, the present invention is not limited to this. For example, multiple biasing portions 5f may be connected to the tilting plate 5d. By adopting such a configuration, for example, it is possible to reduce the biasing force of each biasing portion 5f.

[0088] In the above embodiment, the coil spring 13 is used as the elastic body. However, the present invention is not limited to this. For example, rubber, a leaf spring, or the like can also be used as the elastic body.

[0089] In the above embodiment, the lifting unit is configured to include the lifting platform 4. However, the shape of the lifting unit is not limited to the shape of the lifting platform 4. For example, it is also possible to adopt a configuration in which a box-shaped lifting unit is used.

[0090] In the above embodiment, guide rollers that come into contact with a side surface of the mast 3 other than the guide surface 3a may be provided.

[0091] Furthermore, even when the guide surface 3a is displaced forward parallel to the reference plane M as shown in FIG. 12, or when the guide surface 3a is displaced backward parallel to the reference plane M as shown in FIG. 13, the tilting of the tilting plate 5d allows the guide roller 5e to smoothly follow the guide surface 3a. [Explanation of symbols]

[0092] 1... Stacker crane (lifting device), 1A... Stacker crane (lifting device), 2... Cart section, 3... Mast, 3a... Guide surface (vertical guide surface), 3a1... Inclined surface, 4... Lifting platform (lifting section), 5... Guide section, 5a... Fixed section, 5A... Guide section, 5b... Slide bearing for connecting tilting plate, 5c... Rotating shaft for connecting tilting plate, 5d... Tilting plate (tilting section), 5e... Guide roller, 5f... Pressing section, 5g... Fixed section, 5h... Tilting plate (tilting section), 6... Lifting drive section, 7... Transfer device, 8... Fixed guide section, 10... Rotating shaft for connecting rod tip section, 11... Slide bearing for connecting rod tip section, 12... Rod, 13... Coil spring (elastic body), 14... Bush, 15... Rotating shaft for connecting rod base section (pressing section rotating shaft), 16... Slide bearing for connecting rod base section

Claims

1. A lifting device comprising: a lifting section that can be raised and lowered; and a guide section that is attached to the lifting section and that guides the lifting section in a state of contact with a vertical guide surface, The guide portion is a fixed portion fixed to the lifting portion; a tilting portion pivotally supported so as to be tiltable relative to the fixed portion; a guide roller rotatably attached to the tilting portion and in contact with the vertical guide surface; a biasing portion that biases the tilting portion toward the vertical guide surface; Equipped with The biasing portion is a rod rotatably connected to the tilting portion and supported axially movably relative to the fixed portion; an elastic body that biases the rod toward the tilting portion; Equipped with A lifting device characterized by:

2. 2. The lifting device according to claim 1, wherein the rod is supported tiltably relative to a fixed portion.

3. The biasing portion is a biasing portion rotation shaft pivotally supported by the fixed portion; The lifting device according to claim 2, further comprising: a bushing fixed to the biasing portion rotation shaft and supporting the rod so that the rod can slide in the axial direction.

4. The lifting device according to any one of claims 1 to 3, characterized in that the guide roller is arranged between the connection position between the tilting portion and the fixed portion and the connection position between the rod and the tilting portion.

5. A travelable carriage unit; a mast provided upright on the carriage portion and having the vertical guide surface; an elevation drive unit that raises and lowers the elevation unit; The lifting device according to any one of claims 1 to 4, further comprising:

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