JPH0633878Y2 - Lumber support device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a lumbar support device, and more particularly to a lumbar support device having an improved support operation mechanism.

[Conventional technology]

As shown in FIG. 5, in recent years, it is well known that a backrest 2 of a seat 1 of a vehicle or the like has a built-in lumbar support device 3 so as to reduce fatigue of a driver's waist. .

Conventionally, the lumbar support device 3 is provided at a portion where the lumbar portion of the backrest 2 comes into contact with the lumbar portion so as to apply a pressing force to the lumbar portion. For example, the lumber support device 3 having the structure shown in FIGS. 6 and 7 has been adopted.

As shown in the figure, the lumbar support device 3 mainly includes a strip-shaped lumbar plate 4 for pressing the lumbar region.
And a support operation mechanism 5 for adjusting the amount of movement of the lumbar plate 4 in the front-back direction of the seat 1. The support operating mechanism 5 includes an operating lever 6 provided on the backrest side surface 2a of the seat 1, a cam 8 attached to a rotating shaft 7 rotated by the operating lever 6 and rotating about the shaft, and a mounting frame 9. The torsion spring 11 is mounted on a shaft 10 that is pivotally supported on the shaft 10 and the cam 8 rotates to increase the height h of the cam 8 to urge the mounting base 11a of the shaft 10 to rotate.
It consists of The tip portion 11b of the torsion spring 11 is attached to the central portion of the lumbar plate 4, and moves forward and backward in the front-rear direction FR of the seat 1 to apply a biasing force to the lumber plate 4.

[Problems to be solved by the device]

By the way, in the lumbar support device 3 of this type, as shown in FIGS. 6 and 7, the support operating mechanism 5 urges the mounting base 11a of the torsion spring 11 with the cam 8 and the tip portion thereof. The advancing / retreating stroke S of the cam 11b is adjusted. Since the operation lever 6 is provided on the backrest side surface 2a of the rotary shaft 7 of the cam 8, the lumbar plate 4 and the operation lever 6 are separated from each other. Since it is set in a substantially horizontal position and in a low position, as shown in FIG. 8, the mounting position of the operation lever 6 and the console box 12 are very close to each other, and the operation space D However, there was a problem in terms of operability due to its narrow size.

Further, in order to improve the effectiveness of the lumbar support device 3, it is necessary to increase the advancing / retreating stroke S of the torsion spring 11. For that purpose, the height h of the cam 8 must be increased as shown in FIG. Therefore, the inclination angle A of the cam 8 is increased by the increase in the thickness of the operation lever 6
There was a problem in that the operating load of was increased.

Further, in order to make the advancing / retreating stroke S of the torsion spring 11 stepless, it is necessary to make the inclination angle A of the cam 8 constant as shown in FIG. Cam 8 which is relatively small
Since the inclination of No. 2 is continuous, there is a problem that the cam 8 is rotated by the buckling during use, and the urging position of the cam 8 moves to the lower side of the height h.

Therefore, in order to reduce the operation load of the operation lever 6, as shown in FIG. 11, the shape of the cam 8 is made stepwise to reduce the inclination angle A and prevent the buckling. In order to regulate the rotation of the cam 8,
The stopper 13 had to be engaged with the back surface 8a of the.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to increase the adjustment operation space of the lumbar support and to increase the forward / backward stroke of the torsion spring without increasing the operation load. It is to provide a lumbar support device capable of performing the above.

[Means for Solving the Problems]

In order to achieve the above object, in the ramper support device according to the present invention, a dial type operation knob is rotatably provided above the back side of the seat, and the operation knob is provided with a rotational movement amount. A movement amount conversion mechanism for converting the movement amount in the axial direction is provided, and the lever mechanism is engaged with the movement amount conversion mechanism so as to swing horizontally. The lever mechanism includes a bracket having a U-shaped cross section having a shaft engaging hole and an elongated hole, and an arm member having a U-shaped cross section having a shaft mounting hole and a nut engaging hole corresponding to the bracket.
An arm member having a nut formed by penetrating a female screw portion and a shaft having an upper portion inserted through a shaft mounting hole of an arm member and swingably sandwiched by the fixed bracket via the nut is provided. , The shaft inserted into the shaft engaging hole of the bracket is used as a fulcrum, and the nut moves within the slot of the bracket to swing horizontally. The swing range is determined by the length of the slot of the bracket. Then, the shaft that is suspended and fixed to the arm member is rotated by the swing amount. A torsion spring is attached below the shaft that rotates due to this swinging to move back and forth in the longitudinal direction of the seat by the rotation and to apply a biasing force to the lumbar plate.

[Action]

According to this invention, the operation knob is provided above the back side of the seat, and the movement amount conversion mechanism and the lever mechanism are located at the same height as the operation knob, but are attached to the lumbar plate. Since the torsion spring for giving the force is attached below the shaft which is suspended and fixed to the lever mechanism, the attachment position of the operation knob is largely separated from the console box, so that the adjustment operation space of the lumbar support device is reduced. It will be increased.

Further, the rotation amount of the operation knob is converted into an axial movement amount of the rotation shaft by the movement amount conversion mechanism, and this axial movement amount is transmitted to the shaft which is suspended and fixed thereto via the lever mechanism. It becomes the amount of rotation. Therefore, since the operation knob is of a dial type, if the number of rotations thereof is increased, the forward / backward stroke of the torsion spring attached to the shaft is increased without increasing the operation load.

〔Example〕

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the adjustment operation of the lumbar support device 3 of the present invention is performed by the dial type operation knob 14, and the operation knob 14 is used in the seat 1 as shown in FIG. At least the console box 12 and the like maintain a height L that does not hinder the operation thereof, and are rotatably provided above the backrest left side surface 2a.

A female spline 14a is formed at the center of the operation knob 14, and the female spline 14a has a male spline 1 at one end.
The rotary shaft 15 on which 5a is formed is spline-fitted.
From the other end of the rotating shaft 15 toward the central part, the male screw part 15
b is formed. In the present embodiment, since the lumbar support device 3 is adopted in the driver's seat of the right-hand drive vehicle, the male screw portion 15b is formed with a left screw in consideration of operability. It doesn't matter.

A nut 16 having a female screw portion 16a penetrating the peripheral side portion of the columnar body is screwed into the male screw portion 15b. This nut 16 is an arm member whose side is U-shaped.
It is engaged in a nut engagement hole 17a formed on the back side of 17 and is regulated so as not to rotate following the rotation of the rotary shaft 15. By restricting the rotation of the nut 16 in this way, the nut is rotated when the operation knob 14 is rotated.
16 moves along the axial direction P of the rotating shaft 15 by a screw pitch corresponding to the amount of rotation thereof. That is,
The rotating shaft 15 formed with the male screw portion 15b and the nut 16 formed with the female screw portion 16a constitute a movement amount conversion mechanism 18 for converting the rotation amount of the rotating shaft 15 into the movement amount in the axial direction P thereof. ing.

Also, a shaft mounting hole is provided on the open side of the arm member 17.
17b is formed, and the upper end of the shaft 19 is inserted into this and fixed by a welding W. Further, the arm member 17 is swingably held in a bracket 20 having a U-shaped side surface formed to be wider than the arm member 17.

The upper piece 20a of the bracket 20 has a long hole 20c for engaging and guiding the nut 16 and a shaft engaging hole 20d for inserting the shaft 19, and a lower part. The piece 20b is formed with a long hole 20c which is planarly aligned with the long hole 20c of the upper piece 20a. This bracket 20
Is a seat back frame that is the skeleton of the seat 1.
It is screwed B to a mounting frame 22 for mounting and fixing this device to 21 (shown by a chain line in FIG. 1). That is, the rotary shaft 15 is provided at the center of the upper end of the mounting frame 22.
A U-shaped cutout portion 22a for inserting the cutout portion 22a is formed, and both side pieces are formed so as to be bent so that the cross-section has a V-shaped cross section with the cutout portion 22a sandwiched therebetween. Screw holes Ba are formed in both upper side pieces of the mounting frame 22, respectively, and the bracket 20 is screwed to the seat back frame 21 by a screw Ba. Thus, by fixing the bracket 20 to the mounting frame 22, the nut 16 moves in the elongated hole 20c by the rotation of the rotating shaft 15, whereby the arm member 17 uses the shaft 19 as a fulcrum. It is designed to swing with the nut 16. That is, the bracket 20 and the arm member 17 that is swingably held by the bracket 20 constitute a lever mechanism 23 that swings horizontally by the movement of the nut 16 about the shaft 19 as a fulcrum.

The swinging range of the arm member 17 constituting the lever mechanism 23 is determined by the length of the long hole 20c with which the nut 16 is engaged and guided, and the shaft 19 suspended and fixed to the arm member 17 has its length. It is designed to rotate by the amount of rocking. Below this shaft 19, a strip-shaped lumbar plate 4 built in a portion of the backrest 2 of the seat 1 that abuts the waist portion is moved forward and backward in the front-rear direction FR of the seat 1 and a biasing force is applied to this. Torsion springs for
11 is installed. Specifically, the shaft 19
Is inserted into a coil-shaped spring portion 11c of the torsion spring 11, and a mounting base portion 11a formed between the spring portions 11c is screwed to the shaft 19 B
The hanger member 24 is sandwiched and supported and fixed. The plane shape of the torsion spring 11 is adjusted to the shape of the lumbar plate 4 according to the cross sectional shape of the backrest 2.
Is curved so as to move forward and backward in the front-rear direction FR of the seat 1.

Further, the lower end portion of the shaft 19 has the mounting frame 22
It is inserted and supported through a washer 25 in a shaft support hole 22c opened in the overhanging piece 22b at the lower end of the. The mounting frame 22 has substantially the same length as the shaft 19 for mounting the bracket 20 on the upper end and supporting the shaft 19 on the lower end, and the central portion thereof is screwed to the seat / back frame 21 B The side surface is bent to form a dogleg shape for fixing. Above torsion spring
Behind the spring portion 11c of 11 are two bar portions 11d extending in the vertical width of the lumbar plate 4 so as to traverse the backrest 2 of the seat 1 and a tip portion 11b connecting these bar portions 11d. Is fixed to the lumbar plate 4.

Next, the operation of the above embodiment will be described.

As shown in FIGS. 2 and 3, the male screw portion 15 of the rotary shaft 15
When b is a left screw, when the operation knob 14 is manually turned counterclockwise R, the rotary shaft 15 spline-fitted thereto also rotates counterclockwise R.

When the rotating shaft 15 rotates counterclockwise R, the nut 16 screwed into the male screw portion 15b is engaged in the nut engaging holes 17a formed in the upper and lower pieces of the arm member 17 so as not to rotate. Since it is regulated by the
Along with the arrow Y, it moves to the operation knob 14 side. The nut 16 moves along the axial direction P by a screw pitch corresponding to the rotation amount of the rotating shaft 15, and the rotating shaft 15 formed with the male screw portion 15b and the nut 16 formed with the female screw portion 16a. The rotation amount of the rotary shaft 15 is converted into the movement amount in the axial direction P by the movement amount conversion mechanism 18 composed of.

When the nut 16 moves in the direction of arrow Y, the arm member 17 forming the lever mechanism 23 follows the movement and horizontally swings in the direction of arrow T. The rocking range is a long hole opened in the upper and lower pieces of the bracket 20 that constitutes the lever mechanism 23.
Limited by 20c.

A shaft 19 is hung and fixed to the arm member 17 by welding W, and the lower end of the shaft 19 is supported by the mounting frame 22. Therefore, the arm member 17 swings around the shaft 19 as a fulcrum. This movement causes the shaft 19 to rotate in the direction of arrow T as well. Therefore, since the bracket 20 and the arm member 17 constitute a lever mechanism in which they contact each other over a wide surface, the shaft 19 can be held vertically and wobble of the shaft can be minimized. Moreover, since the shaft itself is a mechanism for rotating, even if the shaft is relatively long, the runout of the rotating shaft does not occur. Since the torsion spring 11 is fixed to the shaft 19 by the hanger member 24, with the rotation thereof, the seat S advances in the forward direction of the seat 1 with a stroke S corresponding to the amount of rotation.

In this way, the state in which the torsion spring 11 is advanced is such that the urging force on the lumbar plate 4 becomes strong and the so-called lumbar support device 3 works well. Therefore, if the operation knob 14 is turned clockwise, the torsion spring 11 is retracted in the rearward direction of the seat 1 with a stroke S corresponding to the amount of rotation of the shaft 19.

Here, the forward / backward stroke S of the torsion spring 11
Is a bracket that substantially constitutes the lever mechanism 23.
It is determined by the length E of the 20 long holes 20c. However, if the length E of the long hole 20c is set to be large and the male screw portion 15b of the rotary shaft 15 is formed to be sufficiently long, since the operation knob 14 is a dial type, the rotational speed of the forward and reverse directions is The torsion spring 11 without increasing the operating load by increasing it.
The forward / backward stroke S can be increased.

The operating force and the rotation speed of the operation knob 14 are the same as those of the male screw portion 15
It can be adjusted by cutting the screw pitch of b and the female screw portion 16a. Furthermore, there is no buckling in use, because the sliding resistance of the male screw portion 15b and the female screw portion 16a exceeds the force of the rotating shaft 15 in the rotating direction.

The operation knob 14 is at least the console box.
12 and the like are provided above the backrest side surface 2a having a height L that does not hinder the operation, and the movement amount conversion mechanism 18 and the lever mechanism 23 are located at the same height as the operation knob 14. It will be. A torsion spring 11 for advancing and retracting the lumbar plate 4 in the front-rear direction FR of the seat 1 and applying an urging force is attached below a shaft 19 which is suspended and fixed to an arm member 17 of the lever mechanism 23. Therefore, as shown in FIG.
Since the mounting position of (1) is largely separated from the console box 12, the adjustment operation space of the lumbar support device 3 can be increased.

[Effect of device]

As described above, the present invention exhibits an excellent effect that the adjusting operation space of the lumbar support can be increased and the advancing / retreating stroke of the torsion spring can be increased without increasing the operation load.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention, FIG. 2 is a plan view showing an embodiment of the present invention, FIG. 3 is a schematic explanatory view showing a lever mechanism adopted in the present invention, and FIG. The figure is a schematic front view showing the positional relationship between the operation knob and the console box of the present invention. FIG. 5 is a perspective view showing a conventional seat, FIG. 6 is a plan view showing a conventional lumbar support device, FIG. 7 is a front view of FIG. 6, and FIG. 8 is an operating lever of the conventional lumbar support device. And FIG. 9 to FIG. 11 are schematic side sectional views showing the shape of the cam of the conventional lumbar support device. 1 ... Seat seat; 2 ... Backrest; 3 ... Lumber support device; 4
… Lumbar plate; 11… Torsion spring; 14… Operating knob; 15… Rotary axis; 18… Moving amount conversion mechanism; 23… Lever mechanism; 19… Shaft.

Claims (1)

[Scope of utility model registration request] 1. A lumbar support device having a torsion spring for applying a biasing force to a lumbar plate, wherein a dial type operation knob rotatably provided above a back side of a seat and a rotary shaft of the operation knob. A movement amount conversion mechanism for converting the rotation movement amount of the to the movement amount in the axial direction,
A lever mechanism that engages with the movement amount conversion mechanism and swings in the horizontal direction, wherein the lever mechanism has a bracket having a U-shaped cross section having a shaft engaging hole and an elongated hole, and a shaft corresponding to the bracket. An arm member having a U-shaped cross section having a mounting hole and a nut engaging hole, a nut formed by penetrating a female screw portion, and a shaft having an upper portion inserted through a shaft mounting hole of the arm member are fixed. In addition, the arm member oscillatably sandwiched by the bracket through the nut uses the shaft inserted into the shaft engaging hole of the bracket as a fulcrum, and the nut moves in the elongated hole of the bracket to move horizontally. Rocks,
Determine the swing range by the length of the long hole of the bracket,
A lumbar support device comprising a shaft fixed to an arm member so as to rotate by a swing amount.