JPH0672193A - Seat lifter - Google Patents

Abstract

PURPOSE:To increase the layout freedom of front and rear link mechanism and reduce the number of part items so as to attain cost reduction. CONSTITUTION:A seat slide rail device 10 is provided fixedly with a leg bracket 20, and front add rear link mechanism 40F, 40R are disposed between the leg bracket 20 and a side bracket 30 fixed to a seat cushion in such a way as to elevate the front and rear parts of the side bracket 30. The link mechanism 40F, 40R are driven by a front and a rear electric motors 51F, 51R, provided orthogonally to the sliding direction, through worms, worm wheels, lead screws 54F, 54R and nut members 56F, 56R screwed with the lead screws 54F, 54R.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat lifter used for adjusting the front-rear height of a seat cushion in an automobile or the like.

[0002]

2. Description of the Related Art As a conventional seat lifter, for example, one disclosed in Japanese Utility Model Laid-Open No. 3-69544 is known.

This is provided between the leg bracket fixed to the seat slide rail device, the side bracket fixed to the seat cushion, and the both brackets so that the front and rear of the side bracket can be moved up and down. It is provided with a linked front and rear link mechanism, and an electric motor drive mechanism that independently drives the front and rear link mechanisms. Then, the electric motors that independently drive the front and rear link mechanisms are opposed to each other and are arranged in a straight line, and the screw bolts that convert the rotational force of the electric motor into a linear movement are opposed to each other and are arranged in a straight line. A nut block is screwed into each of the screw bolts, and the nut block is connected to the link mechanism so that when the occupant is seated on the seat cushion, a force is exerted on the screw bolts so as to face each other.

[0004]

However, in such a conventional seat lifter, since the electric motors are opposed to each other and are arranged in a straight line in parallel with the sliding direction, the space for disposing the link mechanism is reduced. There was a problem that I could not get enough. As a result, the stroke of the link mechanism is limited, and a sufficient lever ratio or the like cannot be obtained. Therefore, the electric motor must be increased in size and drive torque must be increased.

Further, since the screw bolts are also arranged in a straight line so as to face each other, there is a problem that extra cost is inevitable because extra components are required for changing the movement direction for transmitting the driving force by the electric motor. there were.

An object of the present invention is to solve the conventional problems described above, to provide a seat lifter capable of increasing the degree of freedom in layout of the front-rear link mechanism and reducing the number of parts to reduce the cost. It is in.

[0007]

To achieve the above object, the present invention provides a leg bracket fixed to a seat slide rail device, a side bracket fixed to a seat cushion, and a space between the both brackets. A seat lifter provided with a front side and a rear side link mechanism that are interposed and linked to the front and rear of the side bracket so as to be able to move up and down, and an electric motor drive mechanism that independently drives the front and rear link mechanisms, An electric motor driving mechanism, an worm fixed to an output shaft of the electric motor, a worm wheel meshing with the worm, and a lead screw fixed to the worm wheel coaxially.
It is composed of a nut member screwed to the lead screw and connected to the link mechanism, and the electric motor is provided above the seat slide rail device on the leg bracket with its axis orthogonal to the sliding direction.
The worm wheel is arranged between the seat cushion and the seat slide rail device.

[0008]

According to the present invention, the electric motor is provided on the leg bracket above the seat slide rail device so as to be orthogonal to the sliding direction. The rotation of the electric motor is converted into the linear motion of the nut member through the worm, the worm wheel, and the lead screw in this order, and the link mechanism is rotated. As a result, the side bracket is moved up and down, and the height of the seat cushion is adjusted.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 and 2 are a plan view and a side view showing only the left side of a lifter according to an embodiment of the present invention, and the right side is almost mirror-symmetrical except for a part of an electric motor and a link mechanism. It has the same configuration.

In the figure, 10 is a seat slide rail device, which includes a lower rail 14 fixedly mounted on the floor of a vehicle through a mounting bracket 12 and an upper rail 16 fitted to the lower rail 14 so as to be movable back and forth. Mostly equipped. Although the seat slide rail device itself is well known, further detailed description thereof will be omitted. In the present embodiment, a so-called vertical type in which the upper rail 16 has an inverted T-shaped cross section is adopted.

20 is the seat slide rail device 1 described above.
0, in particular, a leg bracket fixedly mounted on the upper rail 16, and as is apparent from FIG. 3, it is extended from one end fixed to the upper rail 16 toward the center of the seat cushion C and the other end is It is bent downward.

Reference numeral 30 denotes a side bracket fixedly provided on the lower surface of the seat cushion C, and reference numeral 40 denotes a link mechanism interposed between the leg bracket 20 and the side bracket 30. The front side link mechanism moves up and down on the front side of the side bracket 30. 40F and a rear side link mechanism 40R that moves up and down on the rear side of the side bracket 30.

Reference numeral 50 denotes an electric motor drive mechanism for driving the above-mentioned link mechanism 40, which is composed of front and rear electric motor drive mechanisms 50F, 50R for driving the front and rear link mechanisms 40F, 40R.

The electric motor drive mechanism 50 has front axes of the front electric motors 5 parallel to each other and arranged in parallel with each other at right angles to the front and rear sliding direction of the seat slide rail device 10.
1F and a rear electric motor 51R, both motors 51
F and 51R are above the seat slide rail device 10 and near the center of the leg bracket 20 in the front-rear direction.
It is fixed with bolts B respectively. A worm 52 is provided on each output shaft of the electric motors 51F and 51R.
F and 52R are fixedly installed on the same axis (the worm casing is labeled in the figure). Further, worm wheels 53F and 53R meshing with the worms 52F and 52R are rotatably supported by the casing, and the casing is provided with the leg bracket 2.
It is fixed to the downward bent portion of 0 by a bolt B (in the figure, the casing is labeled with a worm wheel).

To the worm wheels 53F and 53R, lead screws 54F and 54R extending in the front-rear direction parallel to the sliding direction are fixed, and the lead screws 54F and 54R each have a leg bracket 20 at the tip thereof. Bearing 55 fixed to and supported by
It is rotatably supported by F and 55R.

56F and 56R are lead screws 5
4F and 54R are nut members screwed respectively, and the front side nut member 56F is the front side link mechanism 40 described above.
F and the rear nut member 56R are the rear link mechanism 40R.
And are connected to each other. That is, the front nut member 56F is rotatably connected to one end of the front first link lever 41F of the front link mechanism 40F, and the other end of the first link lever 41F is pivotally attached to one end of the second link lever 42F. . The other end of the second link lever 42F is fixed to a front connecting rod 60F for synchronizing with the right front link mechanism. The third link lever 4 is provided on the connecting rod 60F.
One end of 3F is fixed, and one end of a fourth link lever 44F is pivotally attached to the other end of the third link lever 43F.
The other end of the fourth link lever 44F is pivotally attached to the side bracket 30.

Similarly, the rear nut member 56R is rotatably connected to one end of the rear first link lever 41R of the rear link mechanism 40R, and the other end of the first link lever 41R is an arch-shaped second link. It is pivotally attached to one end of the lever 42R. The other end of the second link lever 42R is fixed to a rear connecting rod 60R for synchronizing with the right rear link mechanism. The third link lever 43R is provided on the rear connecting rod 60R.
Is fixedly attached, and the other end of the third link lever 43R is pivotally attached to the side bracket 30. The front and rear connecting rods 60F and 60R are respectively provided with the leg bracket 2
It is pivotally supported at 0.

Next, 70 is a lead screw for front and rear seat slides, which is rotatably supported by the leg bracket 20 and fixed to the lower rail 14 by a nut member 7.
1 is screwed together. The lead screw 70 is driven by a motor (not shown) via a reduction gear mechanism 72 including a worm and a worm wheel.

In this embodiment, as is apparent from FIG. 3, the lead screw 70 for front and rear seat slides and the nut member 71 are located below the leg bracket 20 on the side of the seat slide rail device 10. And the lead screw 54F of the seat lifter,
Worm wheels 54F and 54R fixed to 54R
Is arranged in a triangular area surrounded by a two-dot chain line in FIG. 3, that is, between the seat cushion C and the seat slide rail device 10. With this arrangement, it is possible to use a large-diameter worm wheel in a limited space, and a large reduction gear ratio can be achieved, so that the electric motor can be downsized and the seat cushion can have a low hip point. It will be easy.

In this embodiment having the above structure, the occupant sits on the seat cushion C and the side bracket 30
When a load is applied to the connecting rods, a force acts to rotate the connecting rods 60F and 60R clockwise. These are the first and second link levers 41F, 42F, 41R,
Although it is input to the nut members 56F and 56R via 42R, the nut members 56F and 56R do not move and the seat cushion C is held in that position due to the irreversible screw engagement with the lead screws 54F and 54R.

Here, the electric motors 51F and 51R are activated to adjust the height or inclination of the seat cushion C. For example, when attempting to lift the front side, the front electric motor 51F is activated, and the nut member 56F is moved to the right in FIG. 2 via the worm 52F, the worm wheel 53F, and the lead screw 54F. By the rightward movement of the nut member 56F, the second link lever 42F, the connecting rod 60F and the third link lever 43F are simultaneously rotated counterclockwise via the first link lever 41F. Then, the third link lever 43
The front side of the side bracket 30 rises via the fourth link lever 44F pivotally attached to the other end of F.

When the rear side of the side bracket 30 is to be lifted, the rear electric motor 51R is started,
Similarly to the case of the front side, the nut member 56R is moved rightward in FIG. Then, the second link lever 42R, the connecting rod 60R, and the third link lever 43R simultaneously rotate counterclockwise via the first link lever 41R, and the side bracket pivotally attached to the other end of the third link lever 43R. The rear side of 30 rises.

[0024]

As is apparent from the above description, according to the present invention, it is possible to increase the degree of freedom in the layout of the front and rear link mechanism, and reduce the number of parts to reduce the cost.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, showing only the left side.

FIG. 2 is a partial cross-sectional side view of an embodiment of the present invention.

FIG. 3 is a rear view of an embodiment of the present invention.

[Explanation of symbols]

 10 seat slide rail device 14 lower rail 16 upper rail 20 leg bracket 30 side bracket 40 link mechanism 50 electric motor drive mechanism 51 electric motor 52 worm 53 worm wheel 54 lead screw 56 nut member 60 connecting rod

Claims (1)

[Claims] 1. A leg bracket fixed to a seat slide rail device, a side bracket fixed to a seat cushion, and a side bracket interposed between the both brackets and linked to the front and rear of the side bracket so as to be able to move up and down. In a seat lifter including front and rear link mechanisms and an electric motor drive mechanism that independently drives the front and rear link mechanisms, the electric motor drive mechanism includes an electric motor, and an output shaft of the electric motor. A worm fixed to the worm, a worm wheel meshing with the worm, a lead screw coaxially fixed to the worm wheel, and a nut member screwed to the lead screw and connected to the link mechanism. ,
Further, the electric motor is provided above the seat slide rail device in the leg bracket with its axis orthogonal to the sliding direction, and the worm wheel is provided between the seat cushion and the seat slide rail device. A seat lifter characterized by that.