JPH0713242U - Rotating chair automatic return device - Google Patents

Abstract

(57) [Summary] [Purpose] A roller attached to a rotating arm, which is rotatably attached to a pedestal and attached to a pedestal, and one end of which is rotatably fixed to the rotator, is provided with elastic biasing means. In an automatic returning device for a rotating chair, which is pressed against a cam fixed to the pedestal so as not to be rotatable, the rotating arm and the rotating arm are rotated without applying an unreasonable bending moment to the pivot point of the rotating arm and the rotating seat. (EN) Provided is an automatic returning device which is excellent in durability without a risk of damage to a shaft that pivotally attaches a seat. [Structure] By forming a recess in the middle of the rotating arm 16 to which the roller 20 is attached, the contact point P1 between the cam 14 fixed to the pedestal 3 and the roller 20 pressed against this, and the rotating arm 16 of the rotating arm 16. The pivot point P2 on the rotary seat 6 is at the same height.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an automatic return device for a swivel chair, and more specifically, a seat plate is rotatably attached to a pedestal, and a roller of a rotating arm attached to the seat plate is attached to a cam fixed to the pedestal. The present invention relates to an improvement of an automatic returning device for a rotating chair, which is configured to automatically return the seat plate of the rotated chair to its original position by pressing the spring with a spring means.

[0002]

[Prior art]

 6 and 7 show an example of a conventional automatic returning device for a swivel chair. In the structure of this automatic return device, first, the rotating seat b attached to the lower surface of the seat plate a of the chair is rotatably attached to the support cylinder d at the upper end of the pedestal c. A cam e having a substantially heart shape in a plan view is fixed to the upper part of the support cylinder d, while one end of a rotating arm g is rotated with respect to the rotating seat b on an axis f on the lower surface of the rotating seat b. The roller i is rotatably rotatably rotatably attached to the lower surface of the intermediate portion of the rotative arm g while being rotatably rotatably rotatably rotatably attached to the rotative arm g by a vane means h. Is pressed against the outer peripheral edge of the cam e fixed to the support cylinder d at the upper end of the pillar c. According to this automatic returning device for a swivel chair, in a normal state in which no person is sitting on the chair, the roller i axially attached to the swivel arm g on the lower surface of the swivel seat b is formed at the rear portion of the heart-shaped cam e. The seat plate a of the chair is rotationally fixed in a state of facing the front. When a person sits on the chair and rotates the seat plate a, the rotating seat b on the lower surface of the seat plate a rotates together with the seat plate a, whereby the roller i of the rotating arm g elastically urges the spring means h. As shown by the imaginary line in the figure, the cam e goes out from the concave portion j of the cam e and moves along the outer peripheral edge of the cam e, but when a person leaves the chair, the outer peripheral edge of the cam e is pressed. The roller i of the rotating arm g rotates the rotating seat b in an attempt to return to the direction of the recess j of the cam e by the elastic biasing of the spring step h, so that the seat plate a of the chair faces the front. It automatically returns to the state of.

[0003]

[Problems to be solved by the device]

 However, in the conventional automatic return device for a swivel chair as described above, the roller i, which is pressed against the outer peripheral edge of the cam e fixed to the pedestal c by the elastic biasing force of the spring means h, is moved by the shaft f. The rotation arm g is rotatably attached to the rotation seat b, and is attached to the lower surface of the rotation arm g in a protruding state. The height H1 of the contact point P1 between the cam e and the roller i and the rotation arm g. And the height H2 of the pivot seat P2 between the rotary seat b and the rotary seat b are deviated from each other by ΔH. For this reason, the roller i is pressed against the outer peripheral edge of the cam e by the elastic biasing force of the spring means h, so that the shaft f is rotated with respect to the shaft attachment point P2 between the rotating arm g and the rotating seat b. There is a problem that a bending moment that twists backward is applied, and the shaft f formed by pivotally attaching the rotating arm g to the rotating seat b is easily damaged. Therefore, in the present invention, an unreasonable bending moment is not applied to the pivotal attachment point P2 between the rotary arm g and the rotary seat b, so that the rotary arm g is pivotally mounted on the rotary seat b. The object of the present invention is to provide an automatic return device for a swivel chair, which has excellent durability and does not have the possibility of damaging f.

[0004]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention has an automatic return device in a swivel chair, in which a rotary seat attached to a seat plate is rotatably attached to a pedestal, and one end of which is pivotally attached to the rotary seat. In an automatic returning device for a rotating chair, in which a roller attached to a rotating arm is pressed against a cam fixed to the pedestal by elastic biasing means, an intermediate portion of the rotating arm to which the roller is attached is vertically moved. Since the cam fixed to the pedestal and the roller of the rotating arm pressed against this are made to have the same height, the height of the contact point between the cam fixed to the pedestal and the shaft of the rotating arm to the rotation seat is the same. It will be.

[0005]

[Action]

 In the automatic returning device for a swivel chair according to the present invention as described above, in a normal state in which no person is sitting on the chair, the roller of the rotating arm pivotally mounted on the swivel seat is fixed on the pedestal. The seat of the chair is rotatably fixed to the front in a recess provided in the outer peripheral edge. Then, when a person sits on the chair and rotates the seat plate, the rotary seat on the lower surface of the seat plate rotates together with the seat plate, and the roller of the rotating arm moves along the outer peripheral edge of the cam against the elastic biasing force. However, when a person leaves the chair, the roller of the rotating arm pressed against the outer peripheral edge of the cam tries to return to the position of the recess on the outer peripheral edge of the cam by the elastic force, and the rotary seat is rotated. The seat plate of the chair automatically returns to its original position with the front facing. In this case, since the contact point between the cam fixed to the pedestal and the roller pressed against it and the pivot point of the rotation arm and the rotation seat to which the roller is attached are at the same height, Even when the roller of the rotating arm is pressed against the cam of the pedestal by the elastic biasing means, no bending moment is applied to the pivot point of the rotating arm and the rotary seat.

[0006]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the drawings. FIG. 1 is a partially cutaway side view showing an example of a swivel chair A which employs an automatic restoration device 1 according to the present invention, and FIG. 2 is a view showing the automatic restoration device 1 part of the swivel chair A from below. FIG. 3 is an exploded perspective view, FIG. 3 is an explanatory side sectional view of the automatic return device 1, FIG. 4 is a bottom view of the automatic return device 1, and FIG. 5 is a rear view.

In this swivel chair A, a seat plate 2 is attached to the upper end of a pedestal 3 fixed to a floor surface F so as to be rotatable and automatically returnable via the automatic return device 1. In the structure, first, a seat support 4 is fixed to the lower surface of the seat plate 2, and slide rails 5 are attached to both inner sides of the seat support 4, and a rotary seat 6 is attached to the slide rail 5 by a slider 7. The rotary seat 6 is mounted so as to be slidable back and forth, and the rotary seat 6 is always elastically biased rearward of the seat support 4 by a tension spring 8. A rotary shaft 9 is projected from the lower surface of the rotary seat 6, and the rotary shaft 9 is inserted into a support cylinder 10 fixed to the upper end of the pedestal 3 so as not to rotate, and the lower end of the rotary shaft 9 is fixed. It is rotatably supported in the support barrel 10 via bushes 11 and 12 mounted above and below the support barrel 10 while being prevented from coming off by a C ring 13 attached to the support barrel 10.

A plate-shaped cam 14 is non-rotatably fixed to the upper part of the support cylinder 10 which is non-rotatably fixed to the upper end of the pedestal 3. The cam 14 has a recess 14a formed on the rear side of the swivel chair A, and has a substantially heart-like shape in plan view that swells left and right gradually from both sides of the recess 14a toward the front top 14b. Has been formed. On the other hand, a bearing portion 15 projecting downward from the lower surface of the rotary seat 6 is provided on the lower surface of the rotary seat 6 attached to the lower surface of the seat plate 2 via a seat support 4 at one rear side of the rotary shaft 9. A rotary arm 16 is rotatably attached to the lower end of the bearing 15 by a shaft 17, and the rotary arm 16 is attached to the other end of a vertical axis 18 and is attached to the upper and lower ends of the vertical arm 18. A roller 20 is elastically urged in the direction of the rotating shaft 9 above and below the cam 14 by springs 19 and 19, and a roller 20 rotatably attached to the middle portion of the rotating arm 16 is fixed to the upper portion of the support cylinder 10. It is attached in a state of being pressed against the outer peripheral edge of the plate-shaped cam 14.

In the present invention, the rotating arm 16 that presses the roller 20 against the cam 14 by the elastic force of the spring 19 is moved up and down on the left and right sides of the roller 20 as shown in FIG. The roller 20 is attached to the concave portion 16a by bending it in the direction, and the contact point P1 between the cam 14 and the roller 20 and the rotary arm 16 are attached to the bearing portion 15 on the lower surface of the rotary seat 6 with respect to the shaft. It is provided such that the heights of the pivot points P2 that are pivotally pivoted by 17 are the same. Further, in the illustrated embodiment, as the roller 20, one provided with flange portions 20a, 20a on the upper and lower outer peripheral edges is used.

In the swivel chair A using the automatic resetting device 1 according to the present invention as described above, in a normal state in which no person is sitting, the swivel seat 6 is seated by the elastic biasing force of the springs 8, 8. The seat plate 2 of the chair is in the most forward position with respect to the pedestal 3 fixed to the floor surface F. Further, the roller 20 of the rotating arm 16 pivotally mounted on the rotating seat 6 has a recess 14a formed in the rear portion of the heart-shaped cam 14 fixed to the support cylinder 10 at the upper end of the pillar 3 fixed to the floor F. Inside, the seat plate 2 of the chair is fixed in rotation while facing forward. Then, when a person sits on the chair and rotates the seat plate 2 to the right or left, the rotary seat 6 attached to the seat support 4 on the lower surface of the seat plate 2 rotates together with the seat plate 2 and the rotating arm 16 Roller 20 moves out of the recess 14a of the cam 14 against the elastic biasing force of the springs 19 and moves along the outer peripheral edge bulging left and right, but when a person leaves the chair, the outside of the cam 14 The roller 20 of the rotating arm 16 pressed against the bulging portion of the peripheral edge rotates the rotary seat 6 in an attempt to return to the recess 14a at the rear portion of the cam 14 by the elastic bias of the springs 19 and 19, thereby rotating the seat of the chair. The plate 2 automatically rotates and returns to the state in which the plate 2 faces the front face.

Further, in this embodiment, the rotary seat 6 attached to the pedestal 3 and the seat support 4 fixed to the lower surface of the seat plate 2 are slidably attached to each other in the front-rear direction, and the tension spring 8 is provided. , 8, the rotary seat 6 is always attached to the rear of the seat support 4 in an elastically biased state, so that a person sits on the chair and pulls the seat plate 2 rearward against the elastic force of the spring 8. In this state, when a person leaves the chair, the seat plate 2 moves forward with respect to the rotary seat 6 by the elastic force of the springs 8 and 8 together with the seat support 4, and automatically returns to the original position. As described above, the rotary seat 6 is provided so as to be slidable back and forth and capable of automatically returning to the seat support 4 fixed to the seat plate 2, and further, the rotary seat 6 rotates with respect to the pedestal 3. Since it is provided so that it can be automatically returned, no matter what position the seatboard 2 is in the front-back direction and at any rotation angle, when the person leaves the chair, the seatboard 2 is in the most forward orientation. In addition, the chair automatically returns to the front, so the chair does not extend into the aisle and get in the way.

Further, in the embodiment, when the seat plate 2 is returned to rotate, the cam 14 is formed in a state of bulging left and right with the top portion 14b formed on the front side thereof being sandwiched therebetween. Therefore, regardless of the angle of the seat plate 2, the seat plate 2 is rotated and returned to the state of facing the front with less rotation. Further, in the present invention, the contact point P1 between the cam 14 fixed to the pedestal 3 and the roller 20 pressed against the cam 14, and the axis of the rotating arm 16 and the rotary seat 6 to which the roller 20 is attached. While the landing point P2 is at the same height, the other end of the rotating arm 16 is also elastically urged by the tension springs 19 and 19 above and below the vertical axis 18 fixed to it and above and below the cam 14. Even when the roller 20 is pressed against the cam 14 by the elastic force of the spring 19, the bending moment is not applied to the pivot point P2 between the rotating arm 16 and the rotating seat 6, and the rotating arm 16 is prevented. The shaft 17 which is rotatably attached to the rotary seat 6 is not damaged by excessive force and is excellent in durability. Further, as in the embodiment, when the roller 20 to be pressed against the cam 14 is provided with the flange portions 20a and 20a on the upper and lower sides thereof, the roller 20 does not come off from the outer peripheral edge of the cam 14. The cam 14 can always be reliably pressed against the cam 14.

[0013]

[Effect of device]

 As described above, according to the automatic returning device for a swivel chair according to the present invention, the rotary seat attached to the seat plate is rotatably attached to the pedestal, and one end is rotatably fixed to the rotary seat. In an automatic returning device for a rotating chair, in which a roller attached to a rotating arm is pressed against a cam fixed to the pedestal, a contact point between the cam fixed to the pedestal and the roller pressed against the cam. Since the pivot arm and the rotary seat are at the same height, the bending moment is applied to the pivot arm and the rotary seat even when the roller is pressed against the cam. It is excellent in durability because there is no risk of damaging the shaft that pivotally mounts the rotary shaft with respect to the rotary seat.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an example of a swivel chair A that employs an automatic restoration device 1 according to the present invention.

FIG. 2 is an exploded perspective view of the portion of the automatic restoration device 1 seen from below.

FIG. 3 is a side cross sectional explanatory view of the automatic restoration device 1 in the same manner.

FIG. 4 is a bottom view of the automatic restoration device 1.

FIG. 5 is a rear view of the automatic restoration device 1.

FIG. 6 is a rear view of a conventional automatic restoration device.

FIG. 7 is a bottom view of a conventional automatic restoration device.

[Explanation of symbols]

 P1 Contact point between cam and roller P2 Axial point between pivot arm and rotary seat A Rotating chair F Floor surface 1 Automatic reset device 2 Seat plate 3 Pillar 4 Seat rest 5 Slide rail 6 Rotating seat 7 Slider 8 Spring 9 Rotating shaft 10 Support tube 11 Bushing 12 Bushing 13 C ring 14 Cam 14a Recess 14b Top 15 Bearing 16 Rotating arm 17 Shaft 18 Vertical axis 19 Spring 20 Roller 20a Collar

Claims (1)

[Scope of utility model registration request] 1. A leg attached by a resilient biasing means to a rotary seat attached to a seat plate so as to be rotatable with respect to a pedestal, and a roller attached to a rotary arm whose one end is rotatably fixed to the rotary seat. In an automatic returning device for a swivel chair, which is pressed against a cam fixed to a column so that it cannot rotate, a cam fixed to a pedestal is formed by vertically arranging an intermediate part of a rotating arm to which the roller is attached. An automatic returning device for a swivel chair, characterized in that a contact point of the rotary arm pressed against the roller with a roller and a shaft attachment point of the rotary arm to the rotary seat are at the same height.