JPH08391A - Vertical adjustment device for seat back - Google Patents

Abstract

PURPOSE:To provide a seat back vertical adjustment device capable of vertically adjusting a seat back, while a user keeping his/her back in contact therewith. CONSTITUTION:When a motor 14 is rotated via a switch 31, motor rotation is converted to the telescopic motion of a telescopic device, and a seat back mounted via a support member 7 can be elevated in the same direction via the expansion and contraction of the device. The elevation of the seat back 6 in a reverse direction, if desired, can be realized by reversing the motor 14 via the switch 31. Thus, a user can elevate the seat back 6 in either vertical directions via one-hand switch operation, and easily and accurately fix the seat back 6 at any position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backrest up / down adjustment device mainly used for office chairs and the like, and relates to a backrest up / down adjustment device for a chair in which a backrest is moved up and down by a lifting device. .

[0002]

2. Description of the Related Art Conventionally, a backrest up-and-down adjusting device, which is mainly used for office chairs and the like, has a back rod that is erected at a rear end of a seat,
The supporting member for mounting the backrest is mounted so as to be slidable in the vertical direction, and also has a stopping means for manually stopping the sliding of both members at a stepwise or arbitrary position.

[0003]

When adjusting the vertical position of the backrest using these devices, the stop means is once manually released and the backrest is manually lifted or pushed down. After adjusting to the user's body shape, the stop means was manually operated to stop the vertical position of the backrest.

For this reason, depending on the device, even if the user has to stand up from the chair and operate from the back of the chair, or if the device can be operated while sitting down, turn both hands to the back of the back and You must operate the stop means with the other hand to operate the backrest with the other hand, and the operability is poor, and the user can adjust the up and down position of the backrest while keeping his back on the backrest. Since it does not exist, there is a drawback that it is difficult to adjust the backrest to an appropriate position.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks of the prior art and to provide an up / down adjustment device for a backrest while the user keeps his back on the backrest.

[0006]

SUMMARY OF THE INVENTION A chair back up and down adjusting device according to the present invention includes a backrest supporting member which is vertically slidably and non-rotatably fitted to a back rod standing at the rear end of a seat. In addition, at the same time by driving a motor capable of forward and reverse drive operation through at least the switch part, one end of an extendable telescopic device is attached to the back rod, and the other end of the telescopic device is attached to the support member. The feature is that the lean is slidable up and down with respect to the back rod.

It is preferable that the switch portion of the drive motor is arranged at a place where the user can reach while sitting.

Guide parts which are oriented in the vertical direction are provided on the left and right sides of a back rod having a substantially U-shaped cross section with its back part closed, and a support member is fitted to the guide rod so as not to be rotatable with respect to the back rod. The expansion / contraction device may be provided in the middle of both the guide portions.

The attachment portion of the telescopic device and the back rod and the attachment portion of the telescopic device and the support member can be pivotally supported so as to be rotatable in the front-back direction of the chair.

[0010]

When the motor is rotated via the switch, the rotation of the motor is converted into the expansion / contraction motion of the expansion / contraction device, and the expansion / contraction of the expansion / contraction device allows the backrest mounted via the support member to move up and down in the same direction. it can. If you want to raise and lower the backrest in the opposite direction, simply rotate the motor in the reverse direction via the switch. Therefore, the user can move the backrest up and down in any direction by simply operating the switch with one hand, and the backrest can be easily and reliably fixed at any position.

By arranging the switch part at a position where the seated person can reach, the user can adjust the backrest up and down with one hand in a natural state while sitting.

Since the supporting member and the expansion / contraction device are provided inside the back rod whose cross section is substantially U-shaped in cross section, the internal mechanism cannot be seen from the outside and the appearance is improved.

When an excessive force is applied to the backrest, the back rod bends and hinders the vertical movement of the support member. However, both ends of the expansion / contraction device are pivotally supported by the back rod and the support member to allow rotation. Therefore, it is possible to form a slight gap between the guide portion and the support member. By forming this gap, it is possible to prevent galling between the guide portion and the support member.

[0014]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partially broken sectional view of a chair to which the present invention is applied,
There is shown a backrest up-and-down adjusting device arranged in the back rod 1.

The back rod 1 is attached to a mounting bracket 4 mounted below the metal seat frame 3 in the seat 2 as shown by a dotted line in the figure.
A tilting shaft 5 is tiltably supported. The backrest 6 is attached to the back rod 1 so as to be vertically slidable via a support member 7 fixed to the rear surface thereof. 31
Is a changeover switch unit for driving the motor 14 to be described later in the forward and reverse directions, and is disposed on the surface of the cover body 32 on the lower surface of the seat. Further, 33 is a battery of the motor 14, which is fixed to the lower surface of the seat frame 3. Further, the battery 33, the switch unit 31, and the motor 14 are connected by a power supply cord 28.

As shown in FIG. 2, the support member 7 is a slide member 10 that slides in an opening 9 provided in the back rod 1 having a closed back portion having a substantially U-shaped cross section, and a slide member 10 of the slide member 10. Two guide members 8, 8 arranged side by side
And a mounting member 11 for the backrest 6 mounted on the front surface of the slide member 10, and a mounting bracket 12 is fixed to the back surface of the slide member 10.

In the back rod 1, a telescopic device 40 constituted by a cylinder 13, a motor 14, a gear box 15, and an elevating member 16 which is vertically slidably fitted in the cylinder 13. Is stored. A projecting piece 17 provided below the gear box 15 is held at one end of the telescopic device 40 by two mounting plates 18, 18 fixed to a predetermined portion of the inner peripheral surface of the back rod 1. Bolt 19 penetrating 17 and mounting plates 18, 18.
Is pivotally attached to the back rod 1.

As shown in FIG. 3, this telescopic device 40
The motor 14 is fixed on the gear box 15 of
Further, the drive shaft 20 of the motor 14 is the gear box 1
5 is fixed to the first gear 21, and the first gear 21 is meshed with the second gear 22 and the second gear 22 to give rotational power to the third gear 23. The gear box 15 serves as a transmission means. I am configuring.

The third gear 23 is connected to a screw rod 24, and the upper end of the screw rod 24 extends from inside the gear box 15 to inside the cylinder 13 above. Further, a male screw portion 25 is formed on the outer periphery of the screw rod 24 extending inside the cylinder 13.

The male screw portion 25 of the screw rod 24 is screwed into the female screw portion 26 formed on the inner circumference of the elevating member 16, and the relative rotation of the screw rod 24 and the elevating member 16 causes the two to move relative to each other. It can be moved up and down. Further, the inside of the elevating member 16 is hollow so that the screw rod 24 can be penetrated when the elevating member 16 is lowered by the relative rotation. The connecting portion 29 at the upper end of the elevating member 16 is held by the mounting member 12 of the supporting member 7 as shown in FIGS.
It is pivotally attached to 2.

As shown in FIGS. 4 and 5, the support member 7 has guide portions 8 in the guide ports 30 of the back rod 1.
Further, the slide members 10 are respectively fitted in the openings 9,
The back rod 1 is slidable in the up-down direction and is non-rotatably fitted to the back rod 1.

Further, since the telescopic device 40 and the supporting member 7 are pivotally attached by the bolts 27 as described above, and the elevating device 40 and the back rod 1 are also pivotally attached by the bolts 19, the backrest 6 is supported. Even if the back rod 1 or the like is slightly bent by the force applied to the support member 7, the support member 7 can be slid smoothly in the back rod 1.

Next, the operation of this embodiment will be described with reference to FIGS. When the motor 14 is used to raise the backrest 6 of the chair in the state shown in FIG.
By pushing the raising switch of the switch unit 31 arranged at a predetermined position of the motor 14, the motor 14 is rotated and the drive shaft 2
0, first gear 21, second gear 22, and third gear 23
The rotational force is transmitted to (without limiting the number of gears), and the screw rod 24 rotates. At that time, the lifting member 16
A part of the support member 7 is fixed to the mounting member 12 via the connecting portion 29 so as not to be horizontally rotatable, and the mounting member 12 is not rotatable horizontally with respect to the back rod 1 via the guide members 8, 8. Therefore, the elevating member 16 is restricted in rotation, and the screw rod 24 rotates with respect to the elevating member 16. A female screw portion 26 is formed on the elevating member 16, and the male screw portion 25 of the screw rod 24 is screwed into the female screw portion 26.
Raise the backrest 6 fixed to.

Next, when it is desired to lower the backrest 6 of the chair, the switch portion 3 installed at a predetermined position of the cover body 32.
By pressing the lowering switch 1 of FIG. 1, the motor 14 rotates in the reverse direction, and the backrest 6 can be lowered in the opposite manner to the above. Even when the backrest 6 is not moved up and down but a rotational force is simply applied to the backrest 6, the support member 7 fixed to the backrest 6 restricts rotation in the back rod 1 through the guide members 8 and 8. Therefore, the backrest 6 does not rotate.

Thus, not only can the motor 14 be driven by operating the switch portion 31 provided on the lower surface of the seat 3 with one hand to freely move the backrest 6 up and down, but also the motor 14 can be stopped. It is also possible to securely hold the backrest 6 at any position without locking it at the moment. In addition, the user can easily adjust the backrest 6 to an arbitrary level with one hand without bothering both hands while sitting.

Further, since the electric motor 14 is used, the switch portion 31 can be installed at any position of the chair even when the motor 14 which is the drive portion is installed inside the back rod 1. When applied to such a structure in which the backrest 6 is tilted by the tilting shaft 5, the switch portion 31 and the motor 14 are connected by the highly flexible energizing cord 28, so that the tilting of the backrest 6 is adversely affected. Never give.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and even if there are changes and additions within the scope not departing from the gist of the present invention, the present invention is not limited. Included in the invention.

For example, a male screw portion is formed on the outer periphery of the elevating member 16, and a drive shaft extending from the third gear into the cylinder 13 is formed into a hollow pipe having a female screw portion on the inner periphery. The male screw portion and the female screw portion may be reversed from the case of the above-described embodiment by screwing the elevating member 16.

[0029]

In the chair up-and-down adjusting device of the present invention, when the motor is rotated through the switch, the rotation of the motor is converted into the expansion and contraction motion of the expansion and contraction device, and the expansion and contraction of the expansion and contraction device causes the support member to move. The backrest attached via the can be raised and lowered in the same direction. If you want to raise and lower the backrest in the opposite direction, simply rotate the motor in the reverse direction via the switch. Therefore, the user can move the backrest up and down in any direction by simply operating the switch with one hand, and the backrest can be easily and reliably fixed at any position.

[0030]

[Brief description of drawings]

FIG. 1 is a partially broken sectional view of a chair according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of FIG.

FIG. 3 is a sectional view of a telescopic device.

FIG. 4 is an enlarged perspective view of a main part of FIG.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

[Explanation of symbols] 1 back rod 2 seat surface 3 seat frame 4 mounting bracket 5 tilting shaft 6 backrest 7 support member 8 guide member 9 opening 10 sliding member 11 mounting member 12 mounting bracket 13 cylinder 14 motor 15 gearbox 16 lifting Member 17 Projecting piece 18 Mounting plate 19 Bolt 20 Drive shaft 21 First gear 22 Second gear 23 Third gear 24 Screw rod 25 Male screw part 26 Female screw part 27 Bolt 29 Connection part 30 Guide port 31 Switch part 32 Cover body 33 Battery 40 telescopic device

Claims (4)

[Claims] 1. A motor capable of vertically and slidably and non-rotatably fitted with a support member of a backrest on a back rod standing upright at a rear end of a seat and at least forward and backward drive operation is possible via a switch portion. Drive one end of the telescopic device attached to the back rod, and the other end of the telescopic device attached to the support member, so that the backrest can be slid vertically with respect to the back rod. A characteristic vertical adjustment device for the backrest of the chair. 2. The switch portion of the drive motor is arranged at a position where a user can reach while sitting on the seat.
An up-and-down adjusting device for the backrest of the chair described in. 3. A back rod having a substantially U-shaped cross section with a closed back portion is provided with guide portions facing left and right, and a supporting member is non-rotatably fitted to the back rod. A telescopic device is provided in the middle of both of the guide portions.
Or the up and down adjustment device for the backrest of the chair according to 2. 4. The mounting portion between the telescopic device and the back rod, and the mounting portion between the telescopic device and the support member are pivotally supported so as to be rotatable in the front-rear direction of the chair, respectively. The up and down adjustment device for the backrest of the chair described.