Movable stand

Abstract

To provide a mobile carriage that can eliminate the need for heavy manual labor during movement, reduce the amount of crane used for moving the carriage, and facilitate fine adjustment of the position.SOLUTION: A mobile carriage 1 comprises a placement base part 2 on which an object to be placed is placed, leg parts 3 that support the placement base part 2 on the upper side and are spaced apart from each other and have lower ends that are in contact with the ground, wheel support parts 4 that integrally support a plurality of wheels 41 arranged on the lower side of each leg part 3, and a switching device 5 that switches between a state in which the wheels 41 are made to protrude downward and become movable, and a state in which the wheels 41 are stored and moved upward and made non-movable. The switching device 5 includes a connecting member 51 that integrally connects both wheel support parts 4 of the leg parts 3, and a hydraulic jack 52 located between the connecting member 51 and the placement base part 2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a stand for placing heavy objects such as columnar structures on an object to be placed.

Background Art

[0002] Conventionally, when manufacturing a steel columnar structure or the like in a factory, this columnar structure is placed on a portal horse stand. Since the above columnar structure is a heavy object, the horse stand supporting it is designed to be sturdy, and the horse stand itself also becomes a heavy object. Note that Patent Document 1 discloses a movable work stand.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the horse stand becomes a heavy object, it becomes necessary to move it using a crane in the factory. In this case, if the crane is not available because it is being used for other work, the horse stand has to be dragged and moved by a plurality of workers, which places a heavy burden on the workers. Also, when dragging the horse stand to move it, there is a risk that the horse stand will tip over, and if it tips over, repair work on the horse stand becomes necessary. Furthermore, in order to avoid the fine members welded to the columnar structure from contacting the horse stand and to place the columnar structure on the horse stand while maintaining its weight balance, fine adjustment of the position of the horse stand is required, but such fine adjustment is not easy with the above dragging.

[0005] In view of the above circumstances, this invention aims to provide a movable platform that eliminates the need for manual dragging during movement, reduces the amount of crane used for moving the platform, and facilitates fine adjustment of its position. [Means for solving the problem]

[0006] The movable stand of this invention comprises: a mounting base on which an object to be mounted is placed; legs spaced apart from each other, supporting the mounting base at the top and having their lower ends in contact with the ground; a wheel support section that integrally supports a plurality of wheels located on the lower side of each leg and is provided to be vertically movable; and a switching device that switches between a state in which the wheels are moved to protrude below the lower ends of the legs to make them movable and a state in which the wheels are moved to a position above the lower ends of the legs to make them immobile. The above-described switching device is characterized by comprising a connecting member that integrally connects the two wheel support portions of the spaced-apart legs, and an operating device that is positioned between the connecting member and the base portion described above and moves in the vertical direction.

[0007] With the above configuration, when moving the movable frame, the wheels only need to be moved to protrude below the lower end of the legs, eliminating the need for heavy dragging work, reducing the amount of crane used to move the frame, and also making fine adjustments to the position of the movable frame easier. On the other hand, when placing an object on the movable frame, the wheels can be retracted above the lower end of the legs, allowing the movable frame to stably support the object.

[0008] Furthermore, the vertical movement of the above-mentioned operating device causes both wheel support sections connected by the connecting member to move as a single unit, and the wheels of both legs extend simultaneously from the lower ends of those legs. This results in improved operability compared to a mechanism that requires operating each leg individually to extend its wheels.

[0009] Each leg may be provided with a guide portion that guides the relative vertical movement between the leg and the wheel support portion. This allows the wheel to be extended stably from the leg by the guide portion.

[0010] The guide section described above has a vertical plate that extends from the lower side to the upper side of the leg, and this vertical plate may also serve as a reinforcing rib for the leg. This reduces the number of plates specifically for reinforcing ribs.

[0011] The above operating device is a manual hydraulic jack, and the operating lever for raising the piston rod of this hydraulic jack may be extended to one of the legs. This allows the operator to manually operate the operating lever from the outside of one of the legs to extend the wheels on both legs.

[0012] The release operation unit for operating the release valve of the hydraulic jack may be extended to one of the legs. This allows the operator to manually operate the release operation unit from the outside of one of the legs to retract the wheels at both legs.

[0013] The base and legs described above may be detachably connected. This would allow the base to be replaced with one of a different size to accommodate changes in the size of the object being placed on it. [Effects of the Invention]

[0014] With this invention, heavy lifting work to drag the movable frame is unnecessary, the amount of crane used to move the frame can be reduced, fine adjustment of the position of the movable frame can be made easier, and when placing columnar structures or the like on the movable frame, the wheels only need to be stored above the lower end of the legs, so that the object placed on the movable frame can be stably supported. Furthermore, because the wheels of both legs extend simultaneously from the underside of the legs due to the vertical movement of the above-mentioned operating device, it has the effect of improving operability compared to operating the wheels of each leg individually. [Brief explanation of the drawing]

[0015] [Figure 1] It is a perspective view showing the movable gantry of the embodiment. [Figure 2] It is a front view of the wheel storage state of the movable gantry shown in FIG. 1. [Figure 3] It is a cross-sectional view taken along the line A-A of FIG. 1. [Figure 4] It is a side view of the wheel storage state of the movable gantry shown in FIG. 1. [Figure 5] It is a side view of the wheel protruding state of the movable gantry shown in FIG. 1. [Figure 6] It is an explanatory view showing a mode of supporting an object to be placed on the movable gantry shown in FIG. 1.

Mode for Carrying Out the Invention

[0016] Hereinafter, embodiments of this invention will be described based on the accompanying drawings. As shown in FIGS. 1, 2, and 3, the movable gantry 1 of this embodiment includes one mounting table portion 2, two leg portions 3, a wheel support portion 4 provided on each leg portion 3, and one switching device 5.

[0017] The above mounting table portion 2 is a portion on which an object to be placed (such as a steel column) is placed, and includes, for example, a load receiving portion 21 in which H-shaped steel is horizontally arranged with its flanges facing up and down. Reinforcement plates 21a are welded and fixed to the above flanges and webs on the central side and both end sides of the load receiving portion 21. Further, on the upper surfaces of both end sides of the load receiving portion 21, receiving columns 22 for preventing the object to be placed from slipping off are fixed by welding or the like.

[0018] An inclined surface portion 22a that slopes downward toward the load receiving portion 21 is formed at the upper end of the above receiving column 22, and when the object to be placed suspended by a crane is lowered from above and placed on the load receiving portion 21, it is easy to guide the object to be placed toward the load receiving portion 21 side.

[0019] In addition, a handle part 24 is fixed to the outer surface of each receiving column 22 (the surface opposite to the load receiving part 21 side). This handle part 24 is a part that an operator can grip when moving the movable mount 1.

[0020] The above-mentioned leg part 3 supports the placement table part 2 on its upper part 31 side, and the lower surface of its lower end part 32 is grounded on the ground side. The two leg parts 3 are spaced apart from each other and are located at the end side of the load receiving part 21, and the position outside the leg part 3 is a position deviated from directly below the object to be placed on the load receiving part 21.

[0021] Also, the leg part 3 is made of, for example, an H-shaped steel with flanges arranged horizontally up and down, and the web extending direction (longitudinal direction) thereof is orthogonal to the web extending direction (longitudinal direction) of the load receiving part 21. The upper part 31 of this leg part 3 consists of an upper flange, and the lower end part 32 consists of a lower flange. Also, reinforcing plates 33 are welded and fixed to the above-mentioned flanges and webs on the central side and both end sides of each leg part 3. The position of the reinforcing plate 33 on the central side coincides with the web position of the load receiving part 21. Both end parts of the lower surface part 25 of the load receiving part 21 are in contact with the upper part 31, and the load receiving part 21 is detachably fixed to the leg part 3 by bolts and nuts 11.

[0022] The above-mentioned wheel support part 4 is located in the inner area of the two areas partitioned by the webs of each leg part 3. Each wheel support part 4 supports two wheels 41 respectively. The two wheels 41 are arranged spaced apart in the web extending direction (longitudinal direction) of the leg part 3. The traveling direction of the wheel 41 coincides with the web extending direction of the leg part 3. An opening 32a for passing the wheel 41 is formed in the lower end part 32 of each leg part 3.

[0023] The above-mentioned wheel support part 4 includes two column parts 42 that are spaced apart from each other in the longitudinal direction of the leg part 3 and are located on the wheel 41. The lower sides of these column parts 42 axially support the wheels 41 rotatably respectively. The substantially central parts of the two column parts 42 are connected and integrated by a beam part 43.

[0024] Each leg portion 3 is equipped with a guide portion 300 that guides the relative vertical movement between the leg portion 3 and the wheel support portion 4. This guide portion 300 is located at each end of the longitudinal direction of each leg portion 3 in the inner region of the two regions, and consists of a vertical plate member 301 erected from the lower end portion 32 to the upper portion 31 of the leg portion, a grooved wheel (door roller) 302 attached to the vertical plate member 301, and a rail portion 303 attached to the column portion 42. Both column portions 42 of each wheel support portion 4 are sandwiched between the two guide portions 300, restricting lateral movement within the leg portion 3 while allowing vertical movement.

[0025] On each column 42 side, two grooved wheels 302 are fixed to the vertical plate 301, spaced apart vertically from each other. Each grooved wheel 302 is rotatably supported by a horizontally positioned shaft. The grooved wheels 302 are fixed, for example, by bolts. Each vertical plate 301 has an L-shaped cross-section and is welded to the upper and lower flanges and web of the leg 3, thus also serving as a reinforcing rib for the leg 3. The rail section 303 is formed, for example, by welding a round steel bar to the column 42.

[0026] As shown in Figures 4 and 5, the switching device 5 switches between a state in which the wheel 41 is moved to protrude below the lower end 32 of the leg portion 3 to make the movable frame 1 movable, and a state in which the wheel 41 is moved to retract above the lower end 32 of the leg portion 3 to make the movable frame 1 immobile. The switching device 5 comprises a connecting member 51, a hydraulic jack 52 as an operating device, an operating lever 53, and a release operating unit 54.

[0027] The connecting member 51 is made of, for example, a square pipe. The two wheel support sections 4 are integrated by connecting their respective central portions with the connecting member 51. In this embodiment, flanges welded to both ends of the connecting member 51 and flanges welded to the beam section 43 of the wheel support section 4 are fixed together with bolts and nuts. In this embodiment, bolted connections are used in places where it is intended that only the damaged portion, rather than the entire component, will be replaced if the component is damaged.

[0028] The hydraulic jack 52 is, for example, a commercially available hydraulic jack and is installed to operate the piston rod 52a vertically at a position between the connecting member 51 and the base portion 2 described above. The hydraulic jack 52 is located on the center of the connecting member 51, and the upper end of the piston rod 52a is positioned at the center of gravity of the base portion 2 described above (the lower part of the central reinforcing plate 21a). Furthermore, a recess 26 with an open bottom is formed on the lower surface of the lower surface portion 25 at the position of the center of gravity of the base portion 2, and the upper end of the piston rod 52a is fitted into this recess 26. The recess 26 is, for example, a short round steel pipe welded and fixed to the lower surface portion 25.

[0029] Furthermore, the hydraulic jack 52 is fixed to the upper surface of the connecting member 51 by bolts and nuts. When the piston rod 52a of the hydraulic jack 52 is in its lowest position, the wheel 41 is positioned above the lower surface of the lower end 32 of the leg portion 3, while when the piston rod 52a extends to a predetermined height or more, the wheel 41 protrudes downward from the lower end 32 of the leg portion 3.

[0030] The hydraulic jack 52 includes a pump unit 52b that sends working fluid into the cylinder to raise the piston rod 52a, and a release valve 52c that removes the working fluid from the cylinder to lower the piston rod 52a. The release valve 52c can, for example, seal the release hole of the hydraulic jack 52 by pressing a steel ball that contacts the release hole with the rotation of a screw part, while simultaneously removing the working fluid from the cylinder by rotating the screw part in a loosening direction.

[0031] The base end of the operating lever 53 is connected to the handle portion used to operate the pump portion 52b. The operating grip portion 53a of the operating lever 53 is located above the upper surface of the upper part 31 of one of the legs 3. For example, the operating lever 53 extends laterally from the handle portion at its base end, and is bent upward near the one of the legs 3, passing directly below the lower surface 25 of the load-receiving portion 21, forming a roughly Z shape with the operating grip portion 53a extending laterally above the upper surface of the leg 3. The tip of the operating grip portion 53a does not extend beyond the outer edge of the upper part 31 (upper flange) of the leg 3. In addition, a clamping portion 31a is provided on the upper surface of the upper part 31 of one of the legs 3 to clamp and hold the operating grip portion 53a in place.

[0032] One end of the release operating section 54 is connected to the threaded portion of the release valve 52c of the hydraulic jack 52, and the other end penetrates the web below the upper part 31 of one of the legs 3 and is located in the outer region of the two regions separated by the web. The other end is then bent approximately 90 degrees in the outer region to form a handle portion 54a. By twisting this handle portion 54a, the threaded portion of the release valve 52c can be rotated. That is, the handle portion 54a of the release operating section 54 is located below the upper part 31 of one of the legs 3 and is hidden by the upper part 31 (upper flange). For example, by fixing a hexagonal socket to one end of the release operating section 54 and fixing a hexagonal member to the threaded portion and engaging them, the engagement angle can be made flexible, preventing damage to the release valve 52c due to relative positional displacement between the connecting member 51 and the leg 3. Furthermore, a stopper 54b that limits the range of rotation of the handle portion 54a is fixed to the web.

[0033] The tip of the handle portion 54a of the release operation portion 54 is positioned so as not to extend beyond the outer edge of the upper portion 31 (upper flange) of the leg portion 3. In addition, pictograms indicating release (wheel retraction: non-movable) and non-release (wheel extension: movable) by rotating the handle portion 54a are attached to the upper surface of the upper portion 31 of one of the leg portions 3.

[0034] With the above configuration, when moving the movable frame 1, the wheels 41 can be moved to protrude below the lower end 32 of the legs 3 (lifting the legs 3 of the movable frame 1), making the movable frame 1 movable. This eliminates the need for heavy lifting work to drag the movable frame 1, reduces the amount of crane used for moving the frame, and also makes fine adjustment of the position of the movable frame 1 easier. On the other hand, when placing an object to be placed on the movable frame 1, the wheels 41 can be moved to retract above the lower end 32 of the legs 3 (lowering the legs 3 of the movable frame 1), making the movable frame 1 immobile, allowing for stable placement of the object to be placed (steel columns, etc.). Figure 6 shows an example of a state in which steel columns P are placed as objects to be placed on two movable frames 1.

[0035] Furthermore, as the piston rod 52a of the hydraulic jack 52 rises, the two wheel support sections 4 connected by the connecting member 51 operate as a single unit, and the wheels 41 of both legs 3 extend simultaneously from the lower ends 32 of the legs 3. This improves operability compared to a mechanism that requires operating the wheels 41 on each side of the legs 3 separately. Also, because it relies on the hydraulic jack 52, the wheels can be extended with minimal effort.

[0036] If a guide section 300 is provided to guide the relative vertical movement between each leg section 3 and the wheel support section 4, the wheel extension from the leg section 3 can be performed stably by the guide section 300.

[0037] The guide section 300 is not limited to the above-described configuration; it may also have a structure in which the column section 42 is equipped with grooved wheels 302 and the upright plate 301 is equipped with rail section 303. However, in this embodiment, if the grooved wheels 302 are bolted to the side of the leg section 3, even if the upright plate 301 on the leg section 3 side is not vertical, or if the verticality deteriorates over time, it becomes easy to make the vertical alignment of the grooved wheels 302 vertical by interposing an adjustment thin plate at the bolt fixing location.

[0038] If the vertical plate 301 of the guide section 300 also serves as a reinforcing rib for the leg section 3, the number of reinforcing plates 33 specifically for the ribs can be reduced.

[0039] If the operating lever 53 for raising the piston rod 52a of the hydraulic jack 52 is extended to one of the leg portions 3, the operator can manually operate the operating lever 53 from the outside of one of the leg portions 3 to extend the wheels at each leg portion 3. Here, the operating lever 53 could also be simply positioned diagonally and extended to one of the leg portions 3, but in this case, the operating lever 53 would be more likely to hit the mounting base portion 2 when moving up and down, and the range of vertical movement of the operating lever 53 would be reduced. On the other hand, if the operating lever 53 is roughly Z-shaped, as in this embodiment, the operating lever 53 would be less likely to hit the mounting base portion 2 when moving up and down, the range of vertical movement of the operating lever 53 could be increased, and the piston rod 52a could be raised with a smaller stroke.

[0040] If the release operating section 54 for operating the release valve 52c of the hydraulic jack 52 is extended to one of the leg sections 3, the operator can operate the release operating section 54 by hand from the outside of one of the leg sections 3 to retract the wheels 41 of each leg section 3. In addition, since the handle portion 54a of the release operating section 54 is positioned below the upper part 31 of one of the leg sections 3 and hidden by the upper part 31, accidental operation of the release operating section 54 can be prevented.

[0041] If the mounting base 2 and the leg portion 3 are detachably connected by bolts and nuts 11, etc., then the mounting base 2 can be replaced with one of a different size to accommodate changes in the size of the object being mounted.

[0042] When the tip of the piston rod 52a of the hydraulic jack 52 is fitted into the recess 26 on the lower surface of the mounting base 2, which has an opening at the bottom, the upward force of the piston rod 52a can be transmitted to the mounting base 2 without slippage, even if the tip of the piston rod 52a is not fixed to the lower surface of the mounting base 2. Furthermore, since the piston rod 52a and the mounting base 2 are not fixed in this way, it becomes easy to replace the mounting base 2 with one of a different size, as described above.

[0043] In the above embodiment, the operating device was a manually operated hydraulic jack, but it is not limited to this. For example, an electric operating device may be used as the operating device, with its battery placed on the connecting member 51 and the operating buttons provided on the leg portion 3.

[0044] Although embodiments of this invention have been described above with reference to the drawings, this invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiments within the same scope as this invention, or within the equivalent scope. [Explanation of symbols]

[0045] 1: Movable stand 2: Mounting platform 3: Legs 4:Wheel support part 5: Switching device 11: Bolts and nuts 21: Load-bearing section 21a: Reinforcement plate 22: Support pillar 22a: Inclined surface part 24: Handle section 25: Bottom part 26: Recess 31: Top 31a: Holding part 32: Bottom end 32a: opening 33: Reinforcement plate 41 :Wheel 42:Column part 43:Beam part 51: Connecting member 52: Hydraulic jack (operating device) 52a: Piston rod 52b: Pump section 52c: Release valve 53: Operating lever 53a: Operation grip 54: Release operation unit 54a: Handle 300: Guide Section 301: Standing board material 302: Grooved car 303: Rail section P: Steel column (object to be placed on)

Claims

1. The device comprises a mounting base on which an object to be mounted is placed, legs spaced apart from each other that support the mounting base from above and whose lower ends touch the ground, a wheel support section that integrally supports a plurality of wheels located on the lower side of each leg and is provided to be vertically movable, and a switching device that switches between a state in which the wheels are moved to protrude below the lower end of the legs to make them movable and a state in which the wheels are moved to a state in which they are retracted above the lower end of the legs to make them immovable. The above-mentioned switching device comprises a connecting member that integrally connects the two wheel support portions of the spaced-apart legs, and an operating device that is positioned between the connecting member and the base portion described above and moves in the vertical direction. The above operating device is a manually operated hydraulic jack, and the operating lever for raising the piston rod of this hydraulic jack extends upwards to the plate-like portion that forms the upper part of one of the legs. The release operation unit for operating the release valve of the above-mentioned hydraulic jack is extended to the leg portion on one side. The movable frame is characterized in that the handle portion of the release operation section is located below the plate-shaped portion which is the upper part of one of the legs, and the plate-shaped portion is located between the operating lever and the handle portion.

2. A movable frame according to claim 1, characterized in that each leg is provided with a guide portion that guides the relative vertical movement between the leg and the wheel support portion.

3. The movable frame according to claim 2, wherein the guide portion has a vertical plate that extends from the lower side to the upper side of the leg portion, and the vertical plate also serves as a reinforcing rib for the leg portion.

4. A movable frame according to claim 2 or claim 3, characterized in that the guide portion causes the relative vertical movement between the leg portion and the wheel support portion to be linear in the vertical direction.

5. A movable frame according to any one of claims 1 to 4, characterized in that the base portion and the leg portion described above are detachably connected.

Images