Work platform

Abstract

To provide a work platform for performing work at heights.SOLUTION: A top plate (1) is supported at an adjustable height by four legs (2) arranged mutually spaced apart in X and Y directions relative to the X and Y directions mutually perpendicular to each other on a plane of the top plate. The legs (2) constitute an extendable leg by slidably inserting a lower leg (4) that rises from a base section installed on a floor surface with respect to an upper leg (3) suspended from the top plate (1). A locking mechanism (6) for connecting adjacent upper legs (3, 3) by an upper connecting rail (7) and for fixedly locking the upper legs (3) and the lower leg (4) in an extended state disabling mutual sliding is provided on the upper connecting rail (7). The locking mechanism (6) releases the fixed lock by moving an operating body (15), which forms a grip portion (15a) outside the upper connecting rail (7), in a direction intersecting with a longitudinal direction P of the upper connecting rail (7).SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a workbench for performing high-altitude work by allowing a worker to stand on a top plate portion. [Background technology]

[0002] Although various types of workbenches have been provided, it is preferable to configure the workbench in a generally box-like shape overall in order to form a flat top panel with a relatively large area and enable stable installation. Also, in order to enable work at different heights, it is preferable to configure the workbench so that the top panel can be held at different heights, i.e., a high position and a low position.

[0003] In this regard, a workbench formed entirely in a box shape from synthetic resin is known (Patent Document 1). This workbench has side panels between rectangular top and bottom panels arranged above and below, a pair of opposing side panels forming folding side panels that can be folded inward so as to fold in half, and another pair of opposing rigid side panels forming support side panels that can be rotated toward the interior space of the box. By extending the folding side panels and fitting the support side panels between the top and bottom panels, a high workbench can be provided, with the top panel held in a high position. Furthermore, by releasing the fitting of the support side panels and storing them between the top and bottom panels, and then bending the folding side panels to bring the top and bottom panels together, a low workbench can be provided, with the top panel held in a low position.

[0004] However, in the workbench of Patent Document 1, in order to change a low workbench into a high one, the top plate must be raised by extending the folding side plates, and then the supporting side plates must be fitted between the raised top plate and the bottom plate, which is a complicated and labor-intensive process. Moreover, if the supporting side plates are not fitted completely, there is a risk that the supporting side plates will come off and the top plate will fall while a worker is standing on the top plate.

[0005] Furthermore, in order to change from a high workbench to a low one, the supporting side panels must be removed and then the top and bottom panels must be brought together via the folding side panels. This not only makes the process complicated, but also poses the risk of injury to the worker's fingers if they become pinched between the folding side panels or the top and bottom panels while they are folded.

[0006] The present applicant has provided a workbench that is composed of an upper base having a top plate and a lower base placed below the upper base, and that can hold the top plate at different heights by moving the upper base relative to the lower base (Patent Document 2). According to this workbench, a plurality of upper legs are provided at intervals on the upper base, and a plurality of lower legs are provided at intervals on the lower base, and the top plate can be held at a low position by storing the upper legs between adjacent lower legs and storing the lower legs between adjacent upper legs. Then, the top plate can be held at a high position by raising the upper base and supporting the upper legs on the lower legs.

[0007] However, while the workbench of Patent Document 2 is highly functional, when the tabletop is held at a high position, the upper legs stored between the lower legs are pulled up together with the upper base, and the upper legs must be rotated to support them on the lower legs. Moreover, the workbench has many components (components) and a complex structure, resulting in a relatively high cost. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 4469483 [Patent Document 2] Patent No. 5400752 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention provides a workbench in which the legs supporting the tabletop are made up of four telescopic legs, each consisting of an upper leg and a lower leg, which are inserted so as to slide freely, and the tabletop is held at a high position when the upper leg is raised and the legs are extended.By minimizing the number of connecting bars connecting adjacent legs, the workbench can be provided at low cost and with a simple structure.Furthermore, the locking mechanism that locks the telescopic legs so that they cannot slide relative to each other when extended is easy to use and allows for safe locking. [Means for solving the problem]

[0010] Therefore, the present invention provides, as a first means, a configuration in which a tabletop is supported in height changeable by four legs arranged at a distance from each other in the X and Y directions, which are orthogonal to each other on the plane of the tabletop, the legs having upper legs hanging down from the tabletop and lower legs standing up from a seat placed on the floor, the lower legs being inserted slidably into the upper legs to form telescopic legs, adjacent upper legs are connected by upper connecting bars, and a locking mechanism is provided on the upper connecting bar to fix and lock the upper legs and lower legs so that they cannot slide relative to each other when extended, the locking mechanism being made up of a rod movable back and forth in a longitudinal direction P of the upper connecting bar, an operating body movable back and forth in a direction intersecting the longitudinal direction P, and a spring, the rod being movable forward and backward the operating body comprises a grip portion attached to the outside of the upper connecting bar and a drive portion formed integrally with the operating body, and is configured to move the drive portion in a direction intersecting the actuating portion when the operating body is moved forward or backward; the drive portion and the actuating portion are interconnected to form an interlocking means that moves the rod backward when the operating body is moved forward and moves the rod forward when the operating body is moved backward; and the spring is configured to apply a resilient biasing force in at least one of the forward movement direction of the rod and the backward movement direction of the operating body.

[0011] In a preferred embodiment, the spring constantly urges the rod in the forward direction to move it forward, thereby holding the operating body in a standby position where it has been moved backward via the interlocking means, and when the operating body is moved forward by gripping the grip, the interlocking means causes the rod to move backward against the spring, and by gripping the grip and raising and lowering the upper connecting bar, the telescopic leg is extended or retracted.

[0012] In another preferred embodiment, the spring constantly urges the operating body in the backward direction to move it backward, thereby holding the rod in a locked position where it has moved forward via the interlocking means; when the operating body is moved forward against the spring by gripping the grip, the interlocking means causes the rod to move backward, and by gripping the grip and raising and lowering the upper connecting bar, the telescopic leg is extended or retracted.

[0013] It is preferable that the locking mechanism be provided with a viewing hole that allows a portion of the rod to be visible from the outside of the locking mechanism when the rod moves forward to the locked position, but that makes the portion invisible when the rod moves backward to the unlocked position.

[0014] The present invention provides a second means for adjusting the height of a tabletop supported by four legs spaced apart in the X and Y directions, which are orthogonal to each other on the plane of the tabletop, the legs including upper legs hanging down from the tabletop and lower legs standing up from a seat placed on the floor, the lower legs being inserted slidably into the upper legs to form telescopic legs, adjacent upper legs being connected by upper connecting bars, and a locking mechanism is provided on the upper connecting bars to lock the upper and lower legs together so that they cannot slide relative to each other when extended, the locking mechanism being connected to rods located outside both ends of the upper connecting bar and supported so as to be movable back and forth in the longitudinal direction P of the upper connecting bar. The rod is composed of an operating body that has a grip portion attached to the outside of the upper connecting bar and is movable back and forth in a direction intersecting the longitudinal direction P, and the rod is provided with a locking means at its tip that engages with the lower leg at a locked position when moved forward and releases the lock at an unlocked position when moved backward, and an operating portion that is formed by bending the tail end is inserted into cam holes and guide holes formed in the operating body and the upper connecting bar, respectively, so that it can move together with the locking means, and the cam hole forms a drive portion with a cam edge portion that contacts the operating portion of the rod, and when the operating body is moved forward in the forward direction, the drive portion pushes the operating portion to form an interlocking means that moves the rod backward.

[0015] In this case, preferably, the grip portion of the operating body is formed by a cylindrical body attached to the outside of the upper connecting bar so as to be freely rotatable in the circumferential direction, and the upper connecting bar and the grip portion are each provided with an inner viewing hole and an outer viewing hole that make the end of the rod located inside the upper connecting bar visible from above, and the outer viewing hole provided in the grip portion is positioned so that the end can be seen only when the rod has moved forward to the lock position and the operating body has moved backward to the rear standby position.

[0016] In the first or second means described above, preferably, the lower leg has a groove formed by recessing inward the wall portion of the cylindrical wall inserted into the upper leg that faces the rod, and a locking hole is provided at the bottom of the groove to allow the rod locking means to be inserted and locked in a removable manner. [Effects of the Invention]

[0017] According to the present invention, in a workbench in which four legs 2 supporting a tabletop 1 are arranged at a distance in the X and Y directions, and each object 2 is composed of an upper leg 3 and a lower leg 4 that can be extended or retracted, the height of the tabletop can be changed. Of the four upper legs 3, two adjacent upper legs in the Y direction are connected by an upper connecting bar 7, and a locking mechanism 6 is provided on the upper connecting bar 7. The locking mechanism 6 has a grip portion 15a on an operating body 15 for operating locking and unlocking using a rod 12, and the grip portion 15a is attached to the outside of the upper connecting bar 7. Therefore, the worker can hold and operate the grip portion 15a, and while still holding it, raise and lower the upper connecting bar 7 together with the operating body 15 to extend or retract the telescopic legs, making it very easy to use. [Brief explanation of the drawings]

[0018] [Figure 1] 1A and 1B show a workbench according to an embodiment of the present invention, in which FIG. 1A is a perspective view showing a state in which the top plate is held at a low position, and FIG. 1B is a perspective view showing a state in which the top plate is held at a high position. [Figure 2] 1 is a perspective view showing an upper unit including a top plate, upper legs, and upper connecting bars, and a lower unit including lower legs and lower connecting bars, separated into upper and lower halves. FIG. [Figure 3] 10 is a perspective view showing an embodiment of a locking mechanism, with components of the locking mechanism disassembled relative to an upper connecting bar of an upper unit; FIG. [Figure 4] 10 is a perspective view showing a state in which a locking mechanism is attached to an upper connecting bar between adjacent legs in the Y direction of the workbench. FIG. [Figure 5]Regarding the locking mechanism, (A) is a perspective view with a part broken away, (B) is an explanatory diagram showing the relationship between the upper connecting bar and the rod, and (C) is an explanatory diagram showing the relationship between the operating body and the rod. [Figure 6] 1 shows the operation of the locking mechanism, where (A) is a plan view in the locked state, (B) is a cross-sectional view showing the interlocking means in the locked state, (C) is a plan view in the unlocked state, and (D) is a cross-sectional view showing the interlocking means in the unlocked state. [Figure 7] 10 is a plan view showing a method of operating an operating body of the locking mechanism for a pair of upper connecting bars arranged side by side. FIG. [Figure 8] Regarding the upper leg and upper connecting bar of the upper unit, (A) is a perspective view showing the state in which the upper connecting bar equipped with a locking mechanism has been removed from the upper leg, and (B) is a perspective view showing the state of the rod. [Figure 9] Regarding the operation of the workbench, (A) is a cross-sectional view showing the state in which the top plate is held in a low position and the upper and lower legs are fixed and locked by the locking mechanism, and (B) is an enlarged cross-section showing the relationship between the legs and the locking means. [Figure 10] Regarding the operation of the workbench, (A) is a cross-sectional view showing the state in which the locking mechanism is released and the upper legs are pulled up from the lower legs, and (B) is an enlarged cross-sectional view showing the relationship between the legs and the locking means. [Figure 11] Regarding the operation of the workbench, (A) is a cross-sectional view showing the state in which the top plate is held in a high position and the upper and lower legs are fixed and locked by the locking mechanism, (B) is an oblique view showing the locking holes of the lower legs, and (C) is a cross-sectional view showing a preferred embodiment of the safety member. [Figure 12] FIG. 10 is a perspective view showing an engaging portion and an engaged portion provided on the lower connecting bar of two workbenches. [Figure 13] 10 is a cross-sectional view showing the state in which two workbenches are integrally connected by engaging an engaging portion with an engaged portion. FIG. [Figure 14] 10A and 10B show another embodiment of the locking mechanism, in which (A) is a perspective view showing a state in which the operating body is separated, and (B) is a perspective view showing a state in which the operating body is assembled. [Figure 15]10A and 10B are cross-sectional views showing the operation of an operating body in a locking mechanism according to another embodiment, in which (A) is a cross-sectional view showing a locked state and (B) is a cross-sectional view showing an unlocked state. DETAILED DESCRIPTION OF THE INVENTION

[0019] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] (Basic configuration) 1 and 2, the workbench supports the top plate 1 so that the height thereof can be freely changed by four legs 2 arranged at intervals in the X and Y directions, which are orthogonal to each other on the plane of the top plate 1. Fig. 1(A) shows the state when the top plate 1 is supported at a low position L, and Fig. 1(B) shows the state when the top plate 1 is supported at a high position H.

[0021] In the illustrated embodiment, the tabletop 1 is formed of a thick, substantially rectangular plate with side edges parallel to the X and Y directions, and legs 2 are provided below the four corners of the tabletop 1.

[0022] Each of the four legs 2 has an upper leg 3 hanging down from the tabletop 1 and a lower leg 4 standing up from a seat 5 placed on the floor. The lower leg 4 is inserted into the upper leg 3 so that it can slide freely, forming an extendable leg. A locking mechanism 6 is provided to lock both legs 3, 4 so that they cannot slide.

[0023] The locking mechanism 6 is provided to fix and lock both legs when at least the upper legs 3 and the lower legs 4 are extended, that is, when the tabletop 1 is raised to the high position H. In the illustrated embodiment, as will be described later, the locking mechanism 6 is configured to fix and lock both legs even when the legs 3 and the lower legs 4 are retracted, that is, when the tabletop 1 is lowered to the low position L.

[0024] In the illustrated example, of the four upper legs 3 that make up the four leg portions 2, two adjacent upper legs 3, 3 in the Y direction are connected by an upper connecting bar 7. In other words, no connecting bar is provided in the X direction. In contrast, of the four lower legs 4 that make up the four leg portions 2, two adjacent lower legs 4, 4 in the X direction are connected by a lower connecting bar 8. In other words, no connecting bar is provided in the Y direction. However, this configuration is not necessarily limited to this, and the arrangement and number of upper connecting bars 7 and lower connecting bars 8 can be configured as desired.

[0025] Preferably, the upper connecting bar 7 connects the upper legs 3, 3 near their lower ends, and the lower connecting bar 8 connects the lower legs 4, 4 near their lower ends.

[0026] 2 and 3, the upper leg 3 is made of a cylindrical section 3a formed from an extruded material of a metal such as aluminum and having a substantially rectangular cross section, and is provided with a bifurcated bracket 3b near the lower end of the upper leg 3. Adjacent upper legs 3, 3 are arranged with the brackets 3b, 3b facing each other, and are connected by fastening with fastening means such as rivets with both ends of the upper connecting bar 7 fitted into the brackets 3b, 3b.

[0027] In contrast, the lower leg 4 is formed from an extruded material made of a metal such as aluminum, and forms a cylindrical body that is slidably fitted into the cylindrical portion 3a of the upper leg 3, and a groove portion 4a is formed by recessing the cylindrical wall of the cylindrical body facing in the Y direction inward.

[0028] A flat seat portion 5 is attached to the lower end of the lower leg 4, and a connecting bracket 9 is provided directly above the seat portion 5, to which the end of the lower connecting bar 8 is attached and fixed. In the illustrated embodiment, the portion near the lower end of the lower leg 4 is inserted into the tubular portion 9a and fixed with a fastening means such as a rivet, with the bifurcated wall 9b facing in the X direction. As a result, the lower legs 4, 4 adjacent in the X direction are arranged with the bifurcated walls 9b, 9b facing each other, and are connected by fitting both ends of the lower connecting bar 8 into the bifurcated walls 9b, 9b and fixing them with a fastening means such as a rivet.

[0029] In the illustrated embodiment, as shown in Figure 2, the upper legs 3 and lower legs 4 that make up the leg section 2 are separated, and the workbench is composed of an upper unit 10 having the top plate 1, four upper legs 3, and two upper connecting bars 7, and a lower unit 11 having four lower legs 4 with the seat section 5, and two lower connecting bars 8.

[0030] Furthermore, the lower unit 11 is composed of a first lower unit 11A and a second lower unit 11B, each having two lower legs 4 and a lower connecting bar 8, and the first lower unit 11A and the second lower unit 11B are arranged at a distance from each other in the Y direction.

[0031] (locking mechanism) 3 to 8 show a preferred embodiment of the locking mechanism 6 provided on the upper connecting bar 7. FIG.

[0032] The locking mechanism 6 is composed of a pair of rods 12, 12 that are movable back and forth in the longitudinal direction P (hereinafter referred to as the P direction) of the upper connecting bar 7, locking the upper leg 3 and the lower leg 4 together by moving forward and releasing the lock by moving backward, a spring 13 that resiliently urges each rod in the forward direction, a support member 14 that supports each rod on the underside of the upper connecting bar 7 so that it can move back and forth, an operating body 15 that is provided on the upper connecting bar 7 and is movable back and forth in the Q direction that intersects the P direction and releases the lock by moving forward, and an interlocking means 20 that moves the rods 12, 12 backward against the spring 13 when the operating body 15 is moved forward.

[0033] 3 to 8, the upper connecting bar 7 is a cylindrical body made of an extruded material of a metal such as aluminum, and has an upper arc wall 7a and a lower arc wall 7b that form concentric arcs in cross section. The operating body 15 is a cylindrical body that is rotatably fitted onto the outer periphery of the upper connecting bar 7, and forms a grip portion 15a located on the outer periphery of the upper connecting bar 7. The operating body 15 is configured to release the lock by moving forward with the rotation direction as the forward / backward movement direction.

[0034] Therefore, when raising the upper unit 10 as described below, the user can grasp the grip portion 15a of the operating body 15 with their fingers, move it forward in the rotational direction, and lift the upper connecting bar 7 as is.

[0035] The rod 12 has a locking means 12a at its tip that engages with the lower leg 4 when it moves forward to the locked position P1 and releases the lock when it moves backward to the unlocked position P2, and an operating part 12b that is bent upward is provided at its tail end, and the operating part 12b is inserted through the lower peripheral wall of the operating body 15 and the lower arc wall 7b of the upper connecting bar 7.

[0036] Therefore, corresponding to the insertion position of the actuating portion 12b, the operating body 15 has a cam hole 16 formed in the lower wall portion of the peripheral wall and an outer see-through hole 18a formed in the upper wall portion. The upper connecting bar 7 has a guide hole 17 formed in the lower arc-shaped wall 7b and an inner see-through hole 18b formed in the upper arc-shaped wall 7a. The actuating portion 12b is inserted through the cam hole 16 and guide hole 17 from below the operating body 15, and an end portion 12c located at the extension end extended from the actuating portion 12b faces the inner see-through hole 18b.

[0037] Fig. 5 shows a state in which the rod 12 has moved forward to the locked position P1 due to the elastic force of the spring 13. As shown in Fig. 5(B), the guide hole 17 in the lower arcuate wall 7b of the upper connecting bar 7 is formed as an elongated hole or slot extending in the P direction, and when the rod 12 moves back and forth between the locked position P1 and the unlocked position P2, the operating portion 12b moves back and forth along the guide hole 17. In the illustrated embodiment, the guide hole 17 is formed long enough to allow the rod 12 to move back in the P direction to a retracted position P3, which will be described later.

[0038] The inner viewing hole 18b is provided directly above the guide hole 17 at a position that coincides with the guide hole 17 in the P direction, and in the illustrated embodiment, is formed as an elongated hole or slot of the same shape as the guide hole 17. However, the inner viewing hole 18b does not necessarily have to be formed so as to extend long in the P direction, and it is sufficient if it is formed with a size and shape that allows the end 12c to be seen from above when the rod 12 is moved to the lock position P1.

[0039] In contrast, as shown in Figure 5(C), the cam hole 16 of the operating body 15 has a long hole 16a that forms a long hole or slot of a length corresponding to the guide hole 17, and a cam edge portion 16b that comes into contact with the operating portion 12b when the operating body 15 is rotated in the forward direction F1, thereby pushing the operating body 15 to the unlock position P2.

[0040] By configuring it in this manner, the cam edge portion 16b forms a drive portion 19 that pushes the operating portion 12b from the intersecting direction, and so when the operating body 15 is rotated in the forward direction F1, the drive portion 19 and the operating portion 12b together form an interlocking means 20 that moves the rod 12 backward to the unlocked position P2.

[0041] The outer see-through hole 18b is disposed so as to face directly above the end 12c of the rod 12 that has moved to the lock position P1 when the operating body 15 is rotated in the backward direction F2 and held in the standby position Q1, and in the illustrated embodiment, is formed as a triangular hole. In this case, the triangular hole serves as a direction marker 21 that indicates the direction in which the operating body 15 operates by aligning the apex of the triangle toward the forward direction F1 of the operating body 15. However, the shape is not limited to a triangle, and the hole may be formed as an arrow-shaped hole, or a direction marker 21 separate from the hole may be provided.

[0042] (Operation of the locking mechanism) Fig. 6 shows the operation of the locking mechanism 6. Fig. 6(A) and (B) show a state in which the rod 12 moves forward to the locked position P1 due to the resilient biasing force of the spring 13, and in conjunction with this, the operating body 15 is rotated in the backward direction F2 and held at a standby position Q1. From this state, as shown in Fig. 6(C) and (D), when an operator grips the grip portion 15a of the operating body 15 and rotates it in the forward direction F1, the driving portion 19 (cam edge portion 16b) constituting the interlocking means 20 pushes the operating portion 12b from the intersecting direction and moves the rod 12 backward along the obliquely intersecting cam edge portion 16b to the unlocked position P2 against the resilient biasing force of the spring 13.

[0043] The operating body 15 rotated in the forward direction is stopped at the operating position Q2 while the operator is holding the grip portion 15a, but when the operator is released from its grip, the opposite occurs to the above, as the spring 13 causes the operating portion 12b of the rod 12 moving forward to push the drive portion 19 (cam edge portion 16b), causing the operating body 15 to rotate in the backward direction F2.As a result, the rod 12 moves forward to the lock position P1, and the operating body 15 rotates in the backward direction F2 to the standby position Q1.

[0044] As shown in Fig. 6(A), when the rod 12 is in the locked position P1, the end 12c of the rod 12 faces the upper viewing hole 18a, and by visually checking this state from above, the operator can confirm that the rod 12 is in the locked state. On the other hand, as shown in Fig. 6(C), when the rod 12 is in the unlocked position P2, the upper viewing hole 18a is displaced by the rotation of the operating body 15, and the end 12c of the rod 12 cannot be seen from above, so by visually checking this state from above, the operator can confirm that the rod 12 is in the unlocked state.

[0045] 1 and 2, the workbench is provided with a locking mechanism 6 on each of a pair of left and right upper connecting bars 7, 7 that are arranged parallel to each other and spaced apart in the X direction. Therefore, when an operator operates the operating body 15 to simultaneously pull up or down the pair of left and right upper connecting bars 7, 7 with both hands, the rotation of the operating body 15 in the forward direction F1 for unlocking and the interlocking means 16 that is actuated thereby are preferably configured symmetrically for the left and right operating bodies 15L, 15R, as shown in FIG. 7. Considering the ease of movement of the operator's hands, it is desirable to configure the forward direction F1 of the right operating body 15R, which is held in the right hand, to be clockwise, and the forward direction F1 of the left operating body 15L, which is held in the left hand, to be counterclockwise, as shown in the figure.

[0046] (Rod retraction position) Incidentally, in the illustrated embodiment, when assembling the upper unit 10 on the workbench, if the pair of upper legs 3, 3 are attached to the top plate 1 and then connected by the upper connecting bar 7, as shown in Figure 8(A), the cylindrical operating body 15 must be previously attached to the upper connecting bar 7 as a component that constitutes the locking mechanism 6. In other words, if the upper connecting bar 7 is first fitted and fixed between the upper legs 3, 3, then in that state, the operating body 15 cannot be attached later.

[0047] Therefore, in order to prevent the locking means 12a at the tip of the rod 12 from interfering with the insertion of the upper connecting bar 7, which has a locking mechanism 6 including an operating body 15 pre-assembled thereto, between the upper legs 3, 3, the guide hole 17 of the upper connecting bar 7 and the long hole 16a of the operating body 15 are formed long in the P direction as shown in Figure 8(B).This makes it possible to retract the rod 12 against the spring 13 to a retracted position P3, which is further retracted than the unlocked position P2, that is, to a position where the locking means 12a at the tip does not protrude from the end face of the upper connecting bar 7.

[0048] (Modified embodiment regarding spring configuration) As described above, the rod 12 and the operating body 15 are configured to interlock with each other via the interlocking means 20. For this reason, in the illustrated embodiment, the rod 12 is configured to be resiliently urged toward the lock position P1 by the spring 13, but instead of or in addition to the configuration in which the rod 12 is provided with the spring 13, a modified embodiment may be configured in which a spring is provided to resiliently urge the operating body 15 toward the standby position Q1.

[0049] In this modified embodiment, the operating body 15 is normally stopped at the standby position Q1 by a spring, and the interlocking means 20 holds the rod 12 at the locked position P1. From this state, when the operator grips the grip portion 15a and rotates the operating body 15 in the forward direction F1 against the spring to the actuated position Q2, the interlocking means 20 moves the rod 12 backward toward the unlocked position P2. Then, when the operator releases the grip portion 15a, the operating body 15 is returned to the standby position Q1 by the spring, and the interlocking means 20 returns the rod 12 to the locked position P1.

[0050] As yet another modified embodiment, the spring 13 can be omitted. The interlocking means 20 is configured so that when the operating body 15 is moved to the standby position Q1, the rod 12 moves to the locked position P1. Conversely, when the operating body 15 is moved to the actuated position Q2, the rod 12 moves to the unlocked position P2. Therefore, even if the spring force of the spring 13 described above does not exist, it is sufficient to provide a retaining means that prevents the operating body 15 and the rod 12 from easily moving toward the actuated position Q2 and the unlocked position P2, respectively, in a locked and engaged state in which the operating body 15 is moved to the standby position Q1 and the rod 12 is moved to the locked position P1. In this case, by operating with a force greater than the retaining force of the retaining means, the operating body 15 can be moved toward the actuated position Q2 and the rod 12 can be moved toward the unlocked position P2.

[0051] (Workbench action) As described above, the workbench is configured so that the height of the tabletop 1 can be freely changed by extending and retracting the upper legs 3 and lower legs 4 that make up the telescopic legs of the leg section 2. Therefore, the tabletop 1 is configured to be supported at a selected height, such as the low position L shown in Fig. 1(A) or the high position H shown in Fig. 1(B). At that time, the locking mechanism 6 locks the upper legs 3 and lower legs 4 so that they cannot be extended or retracted, allowing the worker to work safely on the tabletop 1.

[0052] Figure 9 shows the tabletop 1 supported at low position L, with the upper leg 3 and lower leg 4 of the leg section 2 retracted. In this case, if the lower end 3e of the upper leg 3 is configured to rest on the tubular section 9a of the connecting fitting 9 as shown in Figure 9(B), the weight of the tabletop 1 can be supported appropriately.

[0053] In this state, the rod 12 of the locking mechanism 6 is at the locked position P1, advanced toward the leg 2 by the spring 13, and the locking means 12a at the tip of the rod is inserted through the insertion hole 3c of the upper leg 3 and is inserted and locked into the low-position locking hole 22a formed in the bottom of the groove 4a of the lower leg 4. Therefore, when carrying a workbench with the top plate 1 supported in the low position L, for example, when an operator lifts the upper unit 10 by grasping a component (the top plate 1 or the upper connecting bar 7), the lower unit 11 is also lifted integrally.

[0054] When the rod 12 is advanced to the lock position P1, the lock mechanism 6 rotates the operating body 15 in the backward direction via the interlocking means 20, causing the operating body 15 to wait at a predetermined waiting position Q1.

[0055] Therefore, as described above, when the operating body 15 is rotated in the forward direction, the rod 12 is moved backward to the unlock position P2 against the spring 13 via the interlocking means 20, causing the locking means 12a to retreat and escape from the insertion hole 3c of the upper leg 3, thereby releasing the fixed lock.

[0056] Therefore, if an operator places both hands on the pair of upper connecting bars 7, 7 that make up the upper unit 10 and rotates the operating bodies 15 of each of the locking mechanisms 6, 6 to move the rod 12 back to the unlocked position P2, and then holds the grip portions 15a to hold the operating bodies 15 in the activated position Q2, and then lifts the upper connecting bars 7, 7, the upper unit 10 can be raised toward the high position H, as shown in Fig. 10. At this time, the rod 12 is raised together with the upper connecting bar 7 and the upper leg 3, with the locking means 12a at the tip thereof aligned with the inside of the groove portion 4a of the lower leg 4.

[0057] 10 and 11, when the tabletop 1 reaches the high position H, a high-position locking hole 22b is provided at the bottom of the groove 4a of the lower leg 4 at a location facing the locking means 12a. Therefore, when the tabletop 1 is raised to the high position H and the operating body 15 is released from its forward rotation, the rod 12 moves forward due to the spring 13, and the locking means 12a at the tip is inserted and locked into the high-position locking hole 22b, locking the upper leg 3 and the lower leg 4 so that they cannot be extended or retracted. This allows the worker to work safely on the tabletop 1.

[0058] As a result of the rod 12 moving forward as described above, the operating body 15 is rotated in the backward direction via the interlocking means 20 and returns to the original standby position Q1.

[0059] Therefore, when lowering the tabletop 1 from a state in which it is supported at high position H (FIGS. 1(B) and 11) to a state in low position L (FIGS. 1(A) and 9), the worker places both hands on the upper connecting bars 7, 7, rotates the operating body 15 to release the fixed lock, and then lowers the upper unit 10 while retracting the upper legs 3 and lower legs 4, as described above. When the tabletop 1 reaches low position L, the lower end 3e of the upper leg 3 is placed on the tubular portion 9a of the connecting fitting 9, as described above. Furthermore, when the rotation of the operating body 15 is released, the rod 12 moves forward, inserting and locking the locking means 12a into the locking hole 22a for the low position in the lower leg 4.

[0060] In this regard, in the illustrated embodiment, the locking mechanism 6 is configured to fix and lock the top plate 1 at two height positions, a high position H and a low position L, but the locking holes 22 can be arbitrarily provided in the lower legs 4 between the locking holes 22a for the low position and the locking holes 22b for the high position, and it may be configured to be able to fix and lock at three or more height positions, for example.

[0061] In a preferred embodiment, the high-position locking hole 22b is provided with a safety member 23 below the hole, as shown in Figure 11(B). The safety member 23 is made up of a metal fitting fixed to the bottom of the groove 4a, located directly below the locking hole 22b, and has a canopy-shaped support portion 23a facing the underside of the locking means 12a of the rod 12.

[0062] Therefore, even if the operating body 15 rotates due to an unexpected external force when the tabletop 1 is supported at the high position H, and the tip of the locking means 12a is about to escape from the high-position locking hole 22b, the tip of the locking means 12a is prevented from moving downward by being placed on the support portion 23a of the safety member 23, so there is no danger of the upper unit 10 suddenly dropping together with the tabletop 1.

[0063] In this case, the safety member 23 can be configured as in the embodiment shown in Figure 11 (C), in which case a guide portion 23b is formed that consists of a tapered surface that extends from the support portion 23a to the lower end and continues diagonally downward to the bottom of the groove portion 4a.

[0064] According to this embodiment, when the upper unit 10 is being raised, even if the rotation of the operating body 15 is released and the tip of the locking means 12a of the rod 12 is moved while being in contact with the bottom of the groove portion 4a and sliding, as shown by the chain line, the tip of the locking means 12a rides up onto the guide portion 23b, causing the rod 12 to move backward against the spring 13, and as soon as the locking means 12a faces the locking hole 22b, it can be inserted and locked into the locking hole 22b.

[0065] (Configuration for connecting multiple workbenches) As shown in Figures 12 and 13, the workbench is configured so that a plurality of workbenches can be used in a linked state.

[0066] In the illustrated example, a work platform with the top plate 1 supported at a high position H and a work platform with the top plate 1 supported at a low position L are connected side by side, allowing a worker to get on from the top plate 1 at the low position L, which forms a staircase, to the top plate 1 at the high position H. However, multiple work platforms connected side by side can also be aligned so that the top plates 1 are at the same height (low position L or high position H), in which case the multiple top plates 1 can provide a large floor surface for work.

[0067] To enable such connection, as shown in Fig. 2, an engaging portion 24A and an engaged portion 24B that can be freely engaged with and disengaged from each other are provided on the outer sides of the lower connecting bars 8, 8 of the first lower unit 11A and the second lower unit 11B. In the illustrated embodiment, the engaging portion 24A is formed by a dovetail-shaped recess, while the engaged portion 24B is formed by a protrusion that locks into the recess to prevent it from coming off.

[0068] Therefore, in the illustrated embodiment, the engaging portion 24A and the engaged portion 24B are engaged by fitting into each other from above and below. However, as long as they can be engaged with each other freely and detachably, they are not limited to a configuration of recessed and protruding portions.

[0069] 13, the engaging portions 24A and engaged portions 24B for connecting workbenches are provided on the lower connecting bars 8, 8 of the lower unit 11, so that multiple workbenches arranged side by side can always be easily connected to each other. In other words, the lower connecting bars 8, 8 between adjacent workbenches are always positioned at the same height, so even if one workbench supports the top plate 1 at high position H and the other workbench supports the top plate 1 at low position L, as shown in the figure, the engaging portions 24A and engaged portions 24B can be properly engaged with each other simply by slightly lifting one workbench and then lowering it.

[0070] Furthermore, when multiple workbenches are connected side by side, the upper connecting bars 7 equipped with the locking mechanisms 6 of each workbench have open outer spaces, so that by operating the operating body 15 while the workbenches are still connected, the top plate 1 of any of the workbenches can be raised and lowered between the high position H and the low position L.

[0071] (Second embodiment of locking mechanism) 14 and 15 show another embodiment (referred to as the second embodiment) of the locking mechanism 6. A rod 12 is disposed below the upper connecting bar 7 via a support member 14 so as to be movable back and forth in the direction P, and is provided with locking means 12a at the tip, an operating part 12b at the bent tail end, and an end 12c at the extended end of operating part 12b, and is resiliently biased in the forward movement direction by a spring 13, as in the above-described embodiment, and operating part 12b is inserted into a guide hole 17 in the upper connecting bar 7, as in the above-described embodiment.

[0072] In the second embodiment, the operating body 15 comprises a base 15b arranged facing the underside of the upper connecting bar 7, and a grip portion 15a arranged facing the side surface of the upper connecting bar 7, and the actuating portion 12b is inserted into a cam hole 16 formed in the base portion 15b. Note that the cam hole 16 is formed with an elongated hole 16a and a cam edge portion 16b, the cam edge portion 16b constitutes a driving portion 19, and the driving portion 19 and the actuating portion 12b constitute interlocking means 20, as in the above-described embodiment.

[0073] In the second embodiment, the operating body 15 is supported so that the grip portion 15a can move freely in the direction of approach and separation relative to the side of the upper connecting bar 7 via a bolt 25, that is, so that it can move freely in the Q direction that intersects with the P direction, and is normally held in a standby position Q1 away from the side of the upper connecting bar 7 by a spring 26.

[0074] Therefore, the top surface of the upper connecting bar 7 is open, which has the advantage of providing a tread 27 for a worker to place their feet on when climbing onto the top board 1.

[0075] A viewing hole 28 is formed in the upper wall of the upper connecting bar 7, which makes the end 12c of the rod 12 visible from above when the rod 12 moves forward to the locked position P1, but is positioned so that the end 12c cannot be seen when the rod 12 moves backward to the unlocked position P2.

[0076] As shown in FIG. 15(A), when the rod 12 is in the lock position P1, the operating body 15 is subjected to the resilient force of the spring 26 and is held in the standby position Q1.

[0077] From this state, when the operator grasps the entire upper connecting bar 7 and grip portion 15a with his / her fingers and moves grip portion 15a in a direction approaching the side of the upper connecting bar 7 against the force of spring 26, as shown in Figure 15(B), the base portion 15b moves forward in a direction intersecting the P direction, i.e., the operating body 15 moves forward in the Q direction to the operating position Q2, and the interlocking means 20 moves the rod 12 against the force of spring 13 to the unlocked position P2.

[0078] When the operator releases the grip portion 15a, the operating body 15 is returned to the standby position Q1 by the spring 26, and the rod 12 is returned to the unlocked position P2 by the spring 13. [Explanation of symbols]

[0079] 1 baking sheet 2 legs 3 upper leg 3a Cylindrical part 3b Bracket 3c Insertion hole 3e bottom edge 4 lower legs 4a Groove 5 Seat 6 Locking mechanism 7 Upper connecting bar 7a Upper arc wall 7b Lower arc wall 8 Lower connecting bar 9 Connecting fittings 9a Cylindrical part 9b bifurcated wall 10 Upper unit 11 Lower unit 11A First lower unit 11B Second lower unit 12 rods 12a Locking means 12b Actuating part 12c end P1 Lock position P2 Unlock position P3 Evacuation position 13 Spring 14 Support member 15 Control unit 15a Grip 15b Base F1 Forward direction F2 Reverse direction Q1 Standby position Q2 Working position 16 Cam hole 16a long hole 16b Cam edge 17 Guide hole 18a Outside viewing hole 18b Inner transparent hole 19 Drive unit 20 Linkage means 21 Directional markings 22 Locking hole 22a Locking hole for low position 22b High position locking hole 23 Safety Components 23a Support part 23b Guide part 24A Engagement part 24B Engaged part 25 volts 26 Spring 27 Tread 28 Sight Hole

Claims

1. In a configuration in which the tabletop (1) is supported by four legs (2) spaced apart from each other in the X and Y directions, the X and Y directions being orthogonal to each other on the plane of the tabletop (1), such that the tabletop can be adjusted in height, The legs (2) comprise upper legs (3) suspended from the top board (1) and lower legs (4) erected from the seat placed on the floor, and the lower legs are slidably inserted into the upper legs to form telescopic legs. Adjacent upper legs (3, 3) are connected by upper connecting bars (7), and the upper connecting bars (7) are provided with a locking mechanism (6) that fixes and locks the upper legs (3) and lower legs (4) so ​​that they cannot slide relative to each other when extended. The locking mechanism (6) is composed of a rod (12) movable back and forth in the longitudinal direction P of the upper connecting bar (7), an operating body (15) movable back and forth in a direction intersecting the longitudinal direction P, and a spring (13), The rod (12) has a locking means (12a) at its tip end that engages with the lower leg (4) at a lock position (P1) when the rod (12) has moved forward and releases the engagement at an unlock position (P2) when the rod (12) has moved backward, and an operating part (12b) that is integrally formed with the rod (12); The operating body (15) includes a grip portion (15a) attached to the outer side of the upper connecting bar (7) and a drive portion (19) formed integrally with the operating body, and is configured so that when the operating body (15) is moved forward or backward, the drive portion (19) moves in a direction intersecting with the actuation portion (12b), The drive unit (19) and the operating unit (12b) are connected to each other, thereby constituting an interlocking means (20) that moves the rod (12) backward when the operating body (15) is moved forward, and moves the rod (12) forward when the operating body (15) is moved backward. The spring (13) is configured to exert a spring force in at least one of the forward movement direction of the rod (12) and the backward movement direction of the operating body (15).

2. The spring (13) always resiliently biases the rod (12) in the forward direction to move it forward, thereby holding the operating body (15) at a standby position (Q1) where the operating body (15) has moved backward via the interlocking means (20). When the operating body (15) is moved in a forward direction (F1) by gripping the grip (15a), the interlocking means (20) moves the rod (12) backward against the spring (13), 2. The workbench according to claim 1, wherein the telescopic legs are extended or retracted by gripping the grips (15a) and raising or lowering the upper connecting bars (7).

3. The spring (13) always resiliently biases the operating body (15) in the backward direction (F2) to move it backward, thereby holding the rod (12) at the lock position (P1) where the rod (12) has moved forward via the interlocking means (20). When the grip (15a) is gripped to move the operating body (15) in a forward direction (F1) against the spring (13), the interlocking means (20) moves the rod (12) backward, 2. The workbench according to claim 1, wherein the telescopic legs are extended or retracted by gripping the grips (15a) and raising or lowering the upper connecting bars (7).

4. 2. The workbench according to claim 1, wherein the locking mechanism (6) is provided with a viewing hole (18a) that makes a portion (12c) of the rod (12) visible from the outside of the locking mechanism when the rod (12) moves forward to the locked position (P1), but makes the portion (12c) invisible when the rod (12) moves backward to the unlocked position (P2).

5. In a configuration in which the tabletop (1) is supported by four legs (2) spaced apart from each other in the X and Y directions, the X and Y directions being orthogonal to each other on the plane of the tabletop (1), such that the tabletop can be adjusted in height, The legs (2) include upper legs (3) suspended from the top board (1) and lower legs (4) standing upright from the seat portion placed on the floor, and the lower legs are slidably inserted into the upper legs to form telescopic legs; Adjacent upper legs (3, 3) are connected by an upper connecting bar (7), and a locking mechanism (6) is provided on the upper connecting bar (7) to fix and lock the upper legs (3) and the lower legs (4) so ​​that they cannot slide relative to each other when they are extended, The locking mechanism (6) is composed of a rod (12) located outside both ends of the upper connecting bar (7) and supported so as to be movable back and forth in the longitudinal direction P of the upper connecting bar, and an operating body (15) having a grip portion (15a) attached to the outside of the upper connecting bar (7) and movable back and forth in a direction intersecting the longitudinal direction P, The rod (12) is provided at its tip with a locking means (12a) that engages with the lower leg (4) at a lock position (P1) when moved forward and releases the lock at an unlock position (P2) when moved backward, and an operating portion (12b) formed by bending the tail end is inserted into a cam hole (16) and a guide hole (17) formed in the operating body (15) and the upper connecting bar (7), respectively, so as to be movable together with the locking means (12a). The cam hole (16) forms a drive unit (19) with a cam edge portion (16b) that contacts the operating portion (12a) of the rod (12), and when the operating body (15) is moved forward in the forward direction (F1), the drive unit (19) pushes the operating portion (12a) to move the rod (12) backward, forming an interlocking means (20).

6. The grip portion (15a) of the operating body (15) is formed of a cylindrical body that is attached to the outside of the upper connecting bar (7) so as to be rotatable in the circumferential direction, the upper connecting bar (7) and the grip portion (15a) are provided with an inner viewing hole (18b) and an outer viewing hole (18a), respectively, through which the end portion (12c) of the rod (12) located inside the upper connecting bar (7) can be seen from above; The workbench according to claim 5, characterized in that the outer viewing hole (18a) provided in the grip portion (15a) is provided at a position that makes the end (12c) visible only when the rod (12) has moved forward to the lock position (P1) and the operating body (15) has moved backward to the standby position (Q1).

7. The workbench of claim 1 or 5, characterized in that the lower leg (4) has a groove (4a) formed by recessing inward the wall portion of the cylindrical wall inserted into the upper leg (3) that faces the rod (12), and a locking hole (22) is provided at the bottom of the groove (4a) to allow the locking means (12a) of the rod (12) to be inserted and locked in a freely insertable and detachable manner.

Images