Rotation operation handle for screw type jack device for furniture lifting

Abstract

To provide a rotation operation handle for a screw type jack device for furniture lifting which can accurately press furniture to be fixed to a ceiling surface without excess and deficiency.SOLUTION: A rotation operation handle includes a socket (54) which is rotatably inserted and held at a base end part of a handle body (47) around a vertical axis (O-O). A steel ball (56) stored in the middle section of the handle body is engaged with a ball-receiving recessed groove (55) formed correspondingly on an outer peripheral surface of the socket in an elastically biased state in which the handle body may rotate integrally with the socket, a load more excessive than the elastically biasing force of the steel ball acts on the socket during the rotation operation of a rotation operation shaft by the handle body in which the socket is inserted to and fit to the rotation operation shaft (30) vertical to a screw type jack device, and only the handle body idles.SELECTED DRAWING: Figure 18

Description

[Technical field]

[0001] The present invention relates to a rotating operating handle for a screw jack device for raising and lowering movable storage furniture or other furniture. [Background technology]

[0002] Screw-type jack devices for lifting furniture comprise a number of casters for moving the furniture, a number of jack units interposed between the top and bottom of the furniture and its base, a number of transmission shafts that link the multiple jack units together, and a rotating operating shaft that, by rotating the transmission shaft, raises and lowers all of the jack units in the same direction simultaneously; when the rotating operating shaft is rotated from above using a rotating operating handle, for example in a leftward direction, the furniture descends relative to the rise of the base, and the furniture can be moved by the casters that come into contact with the floor surface. On the other hand, when the rotating operating shaft is rotated in the opposite direction, rightward, the furniture rises relative to the descent of the base, and the furniture is positioned and fixed in a tensioned state between the top and bottom of the ceiling and floor of a residence. These screw-type jack devices for lifting furniture have been well known for some time, as disclosed in, for example, Patent Documents 1 and 2. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6350994 [Patent Document 2] Patent No. 3337457 Summary of the Invention [Problem to be solved by the invention]

[0004] However, while the rotation shaft is being rotated by manually operating the rotation handle, it is extremely difficult to accurately sense the position where the top of the furniture is pressed and fixed against the ceiling of the residence (in other words, the timing when the operation ends when it reaches the top dead center).Since the rotation is usually performed in a blind manner, there is a risk that the ceiling surface will be pushed up too hard, causing it to be distorted and deformed into an upward convex shape, or that it will come loose and be damaged.On the other hand, if the furniture is not pressed firmly against the ceiling surface or is not sufficiently fixed, the furniture itself will rattle or move unexpectedly, which is very dangerous.

[0005] In consideration of variations in ceiling height resulting from changes in a residence over the years, ceiling spacers made of cushioning material of a fixed thickness (for example, 20 mm) are attached to the top surface of the above furniture, but these too are crushed by the above-mentioned blind rotation operation, which currently impedes the convenience of this type of furniture. [Means for solving the problem]

[0006] The present invention aims to solve such problems, and in order to achieve the purpose, the present invention provides a method for installing a furniture member comprising:

[0007] A plurality of transmission shafts that link and connect the plurality of jack units;

[0008] A rotating operation handle of a screw jack device for lifting furniture, comprising a vertical rotating operation shaft that rotates the transmission shaft to lift and lower multiple jack units simultaneously in the same direction,

[0009] It is made up of a handle body of a certain length, a socket inserted and held at the base end of the handle body so as to be rotatable about a vertical axis, and a grip for an operator installed at the tip of the handle body.

[0010] The steel ball housed in the middle of the handle body is engaged with a ball receiving groove formed in the circular outer circumferential surface of the socket in a resilient and biased state so that the handle body can be rotated integrally with the socket around the vertical axis at all times.

[0011] The socket of the handle body is inserted and fitted onto the vertical rotating shaft of the screw jack device so that it can be freely inserted and removed from above and can rotate integrally with the screw jack device. When a load greater than the elastic pressure of the steel ball acts on the socket while the rotating shaft is being rotated to the left or right by the handle body, the steel ball comes out of the ball receiving groove of the socket and the handle body rotates by itself, so that the rotating force is not transmitted to the rotating shaft via the socket.

[0012] In claim 2, a stepped socket holding mouth is formed at the base end of the handle body,

[0013] Similarly, a spring receiving groove communicating with the socket holding mouth is formed in the middle of the handle body so as to extend along the longitudinal center line of the handle body,

[0014] The socket is inserted into the socket holding mouthpiece in a suspended state, and a compression coil spring for elastically biasing the steel ball that engages with the ball receiving groove of the socket is stored in the spring storage groove.

[0015] The socket, the steel ball and the compression coil spring are completely covered by a handle cover which is attached and fixed to the handle body from above.

[0016] Claim 3 is characterized in that the grip held by the operator is in the form of a knob or rod, and is attached and fixed in a state in which it protrudes upward from the tip of the handle body, opposite to the socket. Effect of the Invention

[0017] According to the configuration of claim 1, particularly when used to raise furniture and press it against the ceiling of a house, the socket (joint) held at the base end of the handle body is inserted and fitted into the vertical rotating shaft of the screw jack device so that it can be freely inserted and removed from above and can rotate together with the screw jack device. If a load (rotational torque) greater than the elastic pressure of the steel ball engaged with the socket is applied during the rotation of the handle body, the ball will come out of the ball receiving groove of the socket and the handle body will spin freely. As a result, the rotational force of the handle will not be transmitted to the rotating shaft of the screw jack device via the socket, and the furniture will not be raised. This has the effect of reliably solving the problems of the prior art described at the beginning of this document.

[0018] Furthermore, the rotating operating handle of the above configuration can be freely inserted and removed from above into the vertical rotating operating shaft of the screw-type jack device, so there is no need to modify the configuration of the screw-type jack device and it can be used as is with existing devices to achieve the above-mentioned effects, making it extremely convenient and versatile.

[0019] In this case, if the configuration of claim 2 is adopted, the retaining mouth tube of the socket, the steel ball, and the compression coil spring (torque spring) for elastically biasing the same can all be stored and installed rationally in the handle body of the rotation operating handle, which has a limited size and shape, without the risk of them falling off, and the handle can be easily stored in a handle storage box fitted into the bottom panel of the furniture, without the risk of them getting lost.

[0020] Furthermore, if the configuration of claim 3 is adopted, the grip for the operating hand can be in the form of a knob (knob) or a lever (rod), providing options for ease of grip and design. [Brief description of the drawings]

[0021] [Figure 1] 1 is an enlarged sectional front view of a main portion of a screw jack device for lifting and lowering furniture according to an embodiment of the present invention, showing the furniture being lowered. FIG. [Diagram 2] FIG. 2 is a bottom view showing the entire screw jack device. [Diagram 3] 3 is a cross-sectional view taken along line 3-3 of FIG. 2. [Figure 4] FIG. 4 is an enlarged view showing the jack unit extracted from FIG. 3. [Diagram 5] FIG. 4 is an exploded perspective view showing the operation unit. [Figure 6] FIG. 2 is an exploded perspective view showing a casing of the operation unit. [Figure 7] 4 is an exploded perspective view showing a mounting positional relationship of the operation unit to an intermediate frame on the bottom side of the furniture. FIG. [Figure 8] FIG. 8 is a perspective view showing the mounting state of FIG. 7. [Figure 9] 3 is a perspective view illustrating a rotary operation handle of a rotary operation shaft in the operation unit. FIG. [Figure 10] 10 is an exploded perspective view of the rotary operating handle of FIG. 9. FIG. [Figure 11] 11 is an exploded perspective view of the grip for an operating hand of FIG. 10. FIG. [Figure 12] FIG. 10 is a front view of FIG. [Figure 13] FIG. 13 is a plan view of FIG. 12. [Figure 14] FIG. 13 is a bottom view of FIG. 12. [Figure 15] FIG. 13 is a left side view of FIG. 12. [Figure 16] 16 is a cross-sectional view taken along line 16-16 of FIG. 13, illustrating an engaged state in which the handle body and the socket rotate integrally. [Figure 17] 17 is a plan view showing the engaged state from FIG. 16 with the handle cover removed. FIG. [Figure 18] 17 is a cross-sectional view corresponding to FIG. 16, showing the handle body in an idling state. FIG. [Figure 19]19 is a plan view of the above-mentioned idling state shown in FIG. 18 with the handle cover removed. [Figure 20(a)] 1 is a front view showing a piece of furniture in a lowering operation state in which the casters are in contact with the floor surface. FIG. [Figure 20(b)] FIG. 2 is a front view showing the furniture in a raised state, pressed and fixed against a ceiling surface. [Figure 21] FIG. 2 is a sectional front view corresponding to FIG. 1, showing a main part of the screw jack device in a state where the furniture is raised. [Figure 22] FIG. 4 is a cross-sectional view corresponding to FIG. 3, showing the furniture being raised. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] In the following, a screw-type jack device for raising and lowering movable partition storage furniture according to an embodiment of the present invention will be described in detail. In Fig. 1 to 3, which show the state in which the furniture (P) is operated so that it can be moved, (10) is the rectangular bottom plate of the furniture (P), from whose periphery hangs an enclosing frame (outer base) (11). (12) is the base (inner base) surrounded from the outside by the enclosing frame (11), which can be raised and lowered separately from the furniture (P), and on which multiple (a pair of left and right in the illustrated example) jack support frames (13) are fixed and traversed in parallel.

[0023] On the other hand, on the bottom plate (10) of the furniture (P), there are arranged substantially parallel to each other a plurality of jack mounting frames (14) (also a pair of left and right) facing the jack receiving frame (13) on the base wheel (12), one intermediate frame (15) interposed between the left and right sides of the two jack mounting frames (14), and a plurality of caster mounting frames (16) (also a pair of left and right) arranged in parallel on the outside of the two jack mounting frames (14). (17) and (18) are brackets and fixing screws for attaching the front and rear ends of each of the jack mounting frames (14) and the front and rear ends of the intermediate frame (15) to the four corners of the bottom plate (10) and the surrounding frame (11) of the furniture (P).

[0024] In this case, as is clear from Figure 1, the pair of left and right jack mounting frames (14) and the intermediate frame (15) each have an approximately U-shaped cross section, and the internal space of both jack mounting frames (14) is designed to allow the screw shaft (lifting pillar) of the jack unit (described later) to be inserted into, while the internal space of the intermediate frame (15) is designed to allow the rotating operating shaft of the operating unit (described later) to be inserted into.

[0025] A plurality of jack units (J) (four in the illustrated example) are interposed between the jack mounting frame (14) on the furniture (P) side and the jack receiving frame (13) on the base (12) side. An operating unit (U) is attached to the intermediate frame (15) near the front or rear end.

[0026] In addition, a number of casters (swivel wheels) (19) (four in the illustrated example) are supported on the underside of the caster mounting frame (16), and the casters (19) or the jack unit (J) are used to provide stable support for the bottom plate (10) of the furniture (P) as a whole.

[0027] As is clear from Figures 1 to 4, the multiple jack units (J) are arranged in a symmetrical manner with respect to adjacent units in the left-right and front-to-back directions, but each unit has the same configuration. (20) is a casing fixed and integrated to the underside of the jack mounting frame (14), has a substantially U-shaped cross section, and has a single screw shaft (lifting support) (21) erected on its vertical centerline.

[0028] Moreover, the vertical screw shaft (21) penetrates the casing (20) and its lower end is fixed integrally to the jack support frame (13) on the base wheel (12) side by an anti-rotation seat plate (22) and a fastening screw (23), while its upper end can escape into the internal space of the jack mounting frame (14) through a screw shaft escape hole (24) opening in the underside of the jack mounting frame (14).

[0029] (25) is a female-threaded rotating cylinder screwed onto the screw shaft (21) and is constrained so that it can only rotate within the casing (20). A downward bevel gear (26) protruding continuously from its upper portion is in constant mesh with a horizontal bevel gear (27) that is rotatably supported on the body surface of the casing (20).

[0030] In other words, when the female screw rotating cylinder (25) is rotated to the right (clockwise) or left (counterclockwise) by the meshing bevel gears (26) and (27), the screw shaft (21) that is screwed with it moves up and down only along the vertical center line of the casing (20) as shown in Figures 1 and 3 and Figures 21 and 22, thereby lifting and lowering the base wheel (12). (28) indicates a thrust bearing fitted to the upper end of the female screw rotating cylinder (25), and (29) indicates a bearing collar for the horizontal bevel gear (27).

[0031] The operation unit (U) is composed of a vertical rotating operation shaft (30), a downward bevel gear (31) formed by continuously and integrally protruding from the middle of the shaft, and a pair of opposing lateral bevel gears (32) kept in mesh with the downward bevel gear (31). As shown in Figs. 1 and 21, the rotating operation shaft (30) is rotated to the right (clockwise) (R) or to the left (counterclockwise) (L) about the vertical axis (OO) using a rotating operation handle (H) described later from above the bottom plate (10) of the furniture (P) (inside the furniture itself), thereby allowing the above-mentioned multiple screw jack units (J) to be raised and lowered simultaneously in the same direction at the same speed.

[0032] That is, as shown in Figures 5 to 8, the operating unit (U) is stored inside a casing (37) assembled from a protruding flange portion (33a) of a cover (33) having an approximately U-shaped cross section and a top plate (34) that covers the upper surface of the cover using a plurality of countersunk screws (35) and positioning (centering) protrusions (36), and the top plate (34) and the protruding flange portion (33a) of the cover (33) are attached to an intermediate frame (15) attached to the bottom plate (10) of the furniture (P) by a plurality of fixing bolts (38).

[0033] As shown in FIGS. 1 and 21, the vertical rotating operation shaft (30) of the operation unit (U) penetrates the casing (37) and the intermediate frame (15), and the intermediate height position and the lower end of the rotating operation shaft (30) are journaled in the casing (37) via a pair of upper and lower radial bearings (39), (40) so that the rotating operation shaft (30) only rotates on its own axis. Similarly, the remaining upper end of the rotating operation shaft (30) stands tall as a hexagonal shaft portion (30a) into the inside of a rotating operation shaft escape opening (41) formed by cutting out a portion of the bottom plate (10) of the furniture (P) near the front end or the rear end of the intermediate frame (15).

[0034] In this case, an upper radial bearing (39) that supports the middle portion of the rotary operating shaft (30) is fitted into the top plate (34) of the casing (37), and a lower radial bearing (40) that similarly supports the lower end portion is fitted into the cover (33) of the casing (37). (42) and (43) are the cover plate for the lower radial bearing (40) and the fixing screws therefor.

[0035] Furthermore, a pair of opposing lateral bevel gears (32) meshing with the downward bevel gear (31) of the rotary operating shaft (30) are rotatably supported on the body surface of the cover (33) of the casing (37) via a collar (44), and both lateral bevel gears (32) are interlocked with the corresponding lateral bevel gears (27) of the adjacent jack unit (J) via a transmission shaft (45), preferably made of a hexagonal bar of a required length, as is clear from Figures 1 and 21.

[0036] Therefore, when a rotating operation handle (H) is detachably attached from above to the vertical rotating operation shaft (30) and the rotating operation shaft (30) is rotated to the right (clockwise) (R) or to the left (counterclockwise) (L) around the vertical axis (OO), the downward bevel gear (31) and both lateral bevel gears (32) mesh and rotate, and this rotation action is transmitted to the female thread rotating cylinders (25) of the multiple jack units (J) via both transmission shafts (45). Due to the lifting and lowering movement of the screw shafts (lifting pillars) (21) screwed into these, the bases (12) of the furniture (P) are lifted and lowered all at once in the same direction at the same time, as shown in Figures 1 and 3 and Figures 21 and 22.

[0037] The rotary operating shaft escape port (41) cut into the bottom plate (10) of the furniture (P) is connected to the internal space of the intermediate frame (15) having a substantially U-shaped cross section, and the rotary operating handle (H) is inserted freely into and removed from the rotary operating shaft (30) from here for use. A handle storage box (46) with an opening / closing lid is fitted into the rotary operating shaft escape port (41), so that the rotary operating handle (H) can be stored therein to prevent it from getting lost when not in use.

[0038] The rotary operating handle (H) mentioned above is different from that of the prior art and is specifically designed to function as a torque limiter.

[0039] That is, the specific configuration of the rotating operation handle (H) will be explained with reference to Figures 9 to 17. (47) is a handle body molded into a flat plate of a certain length (e.g. 128 mm) and thickness (e.g. 10 mm) from glass fiber-reinforced polyamide resin (6 nylon) or other high-strength synthetic resin, with a stepped socket holding mouth tube (boss) (48) projecting downward in a continuous, integrated manner from its relatively wide base end, while a grip installation base (49) protrudes upward in a continuous manner from its relatively narrow tip end. (48a) indicates a socket receiving step located midway up the height of the socket holding mouth tube (48).

[0040] (50) is a grip to be held by the operator, which is attached and fixed from above to the grip installation base (49) using a hexagon socket bolt (51) and a pair of upper and lower nuts (52). In the example shown, a grip ball (knob) is shown in shape, but as long as the operator can grasp this by the operator's hand and rotate the rotation operating handle (H), it may be in the shape of a rod (lever) related to the knob shape or in other shapes, and may be installed so as to protrude upward in the opposite direction to the socket holding mouth tube (48).

[0041] Also, (53) is a spring storage groove that is open upward and communicates with the socket holding mouth tube (48), and is cut out and arranged in a row along the longitudinal center line of the handle body (47) with a length of about half that of the handle body (47) biased toward the base end side of the handle body (47). (54) is a socket (joint) that is inserted and fitted into the socket holding mouth tube (48) from above, and is made of zinc alloy and shaped like a stepped cylinder, with its locking step (54a) locking with the socket receiving step (48a) of the socket holding mouth tube (48) in the handle body (47) to be held in a suspended state.

[0042] In the suspended state, the large-diameter head (projecting flange) (54b) above the locking step (54a) of the socket (54) is at a height position facing the spring storage groove (53) of the handle body (47), and a ball receiving groove (55) is recessed in an arc shape into the circular outer circumferential surface of the head (54b). (54c) is a hexagonal bearing hole formed in the lower part of the socket (54) that hangs down from the socket holding mouth (48), and is removably inserted and fitted into the hexagonal shaft (30a) of the rotary operating shaft (30), so that the socket (54) and the rotary operating shaft (30) rotate together.

[0043] As long as they can rotate together, the hexagonal hole portion (54c) on the socket (54) side and the hexagonal shaft portion (30a) on the rotary operating shaft (30) side may be formed into a polygonal shape other than a hexagon or a spline, and may be fitted into each other in a concave-convex manner so that they can be freely inserted and removed from each other.

[0044] (56) is a steel ball for engaging the handle body (47) and the socket (54) held in its socket holding mouth tube (48) so as to rotate together about the vertical axis (OO) of the rotary operating shaft (30), and (57) is a compression coil spring (torque spring) that constantly presses and resiliently urges the steel ball (56) into the ball receiving groove (55) of the socket (54), and is housed in the spring housing groove (53) of the handle body (47). (58) is a spring retainer that is interposed between the steel ball (56) and the compression coil spring (57), and is made of hard synthetic resin (polyacetal).

[0045] In this case, the maximum load (N) of the compression coil spring (torque spring) (57) which applies a resilient biasing force to the steel ball (56) is set to 23 kgf, as an example, and when a load (rotational torque) greater than the preset load is applied during rotation of the rotation operation shaft (30) by the rotation operation handle (H) via the socket (54), the steel ball (56) comes out of the ball receiving groove (55) and only the handle body (47) rotates freely, so that the rotation operation force of the rotation operation handle (H) is not transmitted to the socket (54) and, by extension, to the rotation operation shaft (30). This is the same whether the rotation operation handle (H) is rotated to the right (clockwise) (R) or to the left (counterclockwise) (L).

[0046] Furthermore, (59) is a plate-shaped handle cover molded from the same synthetic resin as the handle body (47), and is attached to the handle body (47) from above using a pair of fixing screws (60) and their fastening nuts (61), thereby completely covering the socket (54), steel ball (56), compression coil spring (57), and its spring retainer (58).

[0047] In addition, the positioning protrusions and the receiving grooves for the positioning protrusions when attaching and fixing the handle cover (59) are formed in a plurality of positions scattered on the handle cover (59) and the handle body (47), and this is indicated by the reference numeral (62) in Fig. 10. It goes without saying that the grip (50) of the operating hand is exposed from the tip of the handle body (47).

[0048] Next, a method of using (operating) the screw jack device for lifting furniture according to the embodiment of the present invention will be described.

[0049] That is, for example, when the movable partition storage furniture (P) is operated to be in a movable state as shown in Figures 1 to 3, the socket (joint) (54) held in the rotary operating handle (H) is inserted into the rotary operating shaft (30) of the operating unit (U) of the screw-type jack device through the rotary operating shaft escape hole (41) of the bottom plate (10) so as to be freely inserted and removed.

[0050] When the hexagonal hole portion (54c) of the socket (54) is inserted into the hexagonal shaft portion (30a) of the rotation operating shaft (30), the socket (54) of the rotation operating handle (H) and the rotation operating shaft (30) can rotate together, and the rotation operating handle (H) is rotated in the left direction (counterclockwise) (L).

[0051] In this way, the rotating shaft (30) rotates around its vertical axis (OO), and the rotation is transmitted from the horizontal bevel gear (32) that rotates in mesh with the downward bevel gear (31) to the multiple jack units (J) via the transmission shaft (45), and the screw shaft (lifting column) (21) of the jack unit (J) raises the base (12) of the furniture (P), thereby lowering the furniture (P) itself, and the multiple casters (19) attached to it touch the floor surface (F) as shown in Figure 20 (a). In this case, the upper surface of the furniture (P) is at a low height position that does not contact the ceiling surface (C) of the residence, so that the furniture (P) can be moved freely and conveniently to change the installation location.

[0052] On the other hand, when the furniture (P) is to be positioned and fixed at a desired installation location, the above-mentioned rotating operation handle (H) is rotated to the right (clockwise) (R), which is the opposite of Figs. 1 to 3. Then, only the direction of rotation is reversed, and the rotating operation shaft (30) of the operating unit (U) rotates about its vertical axis (OO), and this rotation is transmitted simultaneously to the multiple jack units (J) via the downward bevel gear (31), the horizontal bevel gear (32) and the transmission shaft (45). The screw shaft (lifting column) (21) of the jack unit (J) lowers the base (12) of the furniture (P) as shown in Figs. 21 and 22, while raising the furniture (P) itself, and the multiple casters (19) attached to it rise above the floor surface (F).

[0053] In this case, as shown in FIG. 20(b), the lowered base (12) touches the floor surface (F), while the upper surface of the furniture (P) touches the ceiling surface (C) of the residence. However, if the rotation of the rotation operation shaft (30) by the rotation operation handle (H) is continued, the elasticity of the compression coil spring (torque spring) (57) which presses the steel ball (56) of the handle body (47) of the rotation operation handle (H) into the ball receiving groove (55) of the socket (joint) (54) separate from the handle body (47) may increase. When a load (rotational torque) greater than the pressing force (maximum load) is applied, the steel ball (56) will naturally come out of the ball receiving groove (55) of the socket (54) as shown in Figures 16, 17 to 18 and 19, and only the rotation operating handle (H) will rotate freely. As a result, the rotation operating force of the handle (H) will not be transmitted via the socket (54) to the rotation operating shaft (30) or further to the transmission shaft (45) and to the multiple screw-type jack units (J), and the transmission will be stopped (disconnected).

[0054] In other words, if a strong rotational force is applied by the rotation operating handle (H) until the cushioned ceiling spacer (63) attached to the top surface of the furniture (P) is completely crushed to a certain thickness (t) (the 20 mm example given above), and the timing to end the force is incorrect, it may distort or deform the ceiling surface (C) of the residence or cause cracks in the ceiling surface (C). On the other hand, if the furniture (P) is not firmly pressed against the ceiling surface (C) in a weak or insufficient manner, it may cause the furniture (P) to move unexpectedly, and these situations are prevented by using the rotation operating handle (H) having the above configuration.

[0055] In this regard, by using the rotary operating handle (H) of the above configuration in place of that of the prior art, the problems of the prior art mentioned at the beginning can be solved, and there is no need to modify the operating unit (U) including the rotary operating shaft (30) of the screw jack device for lifting furniture or other components, and the existing device can be used as is, which is extremely convenient in practical use.

[0056] Furthermore, unlike ratchet handles and torque wrenches, the rotation operation handle (H) of the above configuration does not require the preparation of two types, one for left-handed use and one for right-handed use, or the addition of a mechanism for switching between them. The same effect can be achieved whether the handle is rotated in the left or right direction during use.

[0057] In the illustrated example, the maximum load (N) (resilient compressive force) of the compression coil spring (torque spring) (57) is set to 23 kgf, and the fixed thickness (t) of the ceiling spacer (63) is set to 20 mm. When 5 mm (one-fourth) of the thickness is crushed (compressed), the compression coil spring (57) acts as a torque spring and causes the rotary operating handle (H) of the rotary operating shaft (30) to rotate freely. However, there is no intention to limit the set values ​​to these values ​​and they can be determined as appropriate.

[0058] Furthermore, it goes without saying that from the state in which the furniture (P) in Figures 21 and 22 is positioned and fixed, the furniture (P) can be moved along the floor surface (F) by rotating the rotation operating handle (H) again in the left direction (counterclockwise) (L). [Explanation of symbols]

[0059] (10)...Bottom plate (11) Enclosure (outer base) (12) Base (13) Jack support frame (14) Jack mounting frame (15) Intermediate frame (16) Caster mounting frame (19) Caster (20) Casing (21) Screw shaft (lifting support) (25) Female thread rotating cylinder (26) Downward bevel gear (27) Horizontal bevel gear (30) Rotational operation shaft (31) Downward bevel gear (32) Horizontal bevel gear (37) Casing (45) Transmission shaft (47) Handle body (48) Socket holding nozzle (49) Clip installation stand (50) Grip for operating hand (53) Spring storage groove (54) Socket (55) Ball receiving groove (56) Steel ball (57) Compression coil spring (torque spring) (59)···Steering wheel cover (C)...Ceiling surface (F)...Floor surface (H) Rotation control handle (J) Jack unit (OO)...Vertical axis (P)...Furniture (U) Operation unit

Claims

1. A plurality of jack units interposed between the upper and lower parts of the furniture and its base; A plurality of transmission shafts that link and connect the plurality of jack units; A rotating operation handle of a screw jack device for lifting furniture, comprising a vertical rotating operation shaft that rotates the transmission shaft to lift and lower multiple jack units simultaneously in the same direction, It is made up of a handle body of a certain length, a socket inserted and held at the base end of the handle body so as to be rotatable about a vertical axis, and a grip for an operator installed at the tip of the handle body. The steel ball housed in the middle of the handle body is engaged with a ball receiving groove formed in the circular outer circumferential surface of the socket in a resilient and biased state so that the handle body can be rotated integrally with the socket around the vertical axis at all times. A rotating operation handle of a screw type jack device for lifting furniture, characterized in that the socket of the handle body is inserted and fitted into the vertical rotating operation shaft of the screw type jack device so that it can be freely inserted and removed from above and can rotate together with the vertical rotating operation shaft, and when a load greater than the elastic pressure of the steel ball acts on the socket while the rotating operation shaft is being rotated in either the left or right direction by the handle body, the steel ball comes out of the ball receiving groove of the socket and the handle body alone rotates freely, so that the rotating operation force is not transmitted to the rotating operation shaft via the socket.

2. A stepped socket holding mouth is formed at the base end of the handle body, Similarly, a spring receiving groove communicating with the socket holding mouth is formed in the middle of the handle body so as to extend along the longitudinal center line of the handle body, The socket is inserted into the socket holding mouthpiece in a suspended state, and a compression coil spring for elastically biasing the steel ball that engages with the ball receiving groove of the socket is stored in the spring storage groove.

2. The rotation operating handle of a screw jack device for lifting furniture according to claim 1, wherein said socket, steel ball and compression coil spring are completely covered by a handle cover which is attached and fixed to said handle body from above.

3. 2. The rotating operating handle of a screw jack device for lifting furniture according to claim 1, wherein a grip held by an operating hand is in the form of a knob or rod and is attached and fixed in a state in which it protrudes upward from the tip of the handle body, opposite to the socket.

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