JPH06336130A - Power seat sliding device - Google Patents

Abstract

PURPOSE:To improve the sitting feeling by the suppressing the chattering feeling of a seat, softening the shock of the seat on the stop at the front and rear edges of the stroke without incurring the cost increase, and preventing a driver from being applied with the discomfortable feeling. CONSTITUTION:An elastic member 60 having through holes 63 and 64 through which a screw member 41 penetrate is interposed between a nut member 42 which constitutes a driving part and a housing 50, and annular projections 63a and 64a are formed at the peripheral edges of the through holes 63 and 64, and the inner peripheries of the through holes 63 and 64 are brought into slide contact with the outer periphery of the screw member 41 so that the chattering feeling due to the fine movement of the backlash portion of the nut member is softened. Further, a softening part set along the front and rear edge parts 51 and 52 of the housing 50 is formed at the front and rear edges of the elastic member 60a, and the softening part is springily attached at a stopper part at the front and rear edges of the shift stroke of the nut member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a vehicle body side rail and a seat side rail that is fitted to the vehicle body side rail so as to be movable back and forth and supports a seat. The present invention relates to a power seat slide device that adjusts the front-back position of a seat by moving the seat back and forth with an electric motor.

[0002]

2. Description of the Related Art As a conventional power seat slide device, there is one shown in FIGS. 12 and 13, for example. That is, a vehicle body side rail 1 and a seat side rail 2 which is fitted to the vehicle body side rail 1 so as to be movable back and forth and supports a seat.
The seat-side rail 2 is moved back and forth via the drive unit to adjust the front-back position of the seat. The drive unit is rotatably supported on the seat-side rail 2 via a gear box 3 and a bearing member 4, and is relatively driven by a screw member 5 driven to rotate by an electric motor (not shown). And a nut member 7 that is rotatably screwed into and is fitted into a housing 6 that is fixed to the vehicle body side rail 1.

As shown in FIG. 12, between the nut member 7 and the housing 6, an elastic member 8 for absorbing a shock at the time of starting is usually interposed. That is, as shown in FIG. 13, the nut member 7 was fitted into the housing 6 via the elastic member 8 having a similar shape to the housing 6 and having the through hole 8a for penetrating the screw member 4. By the way, conventionally, the through hole 8a formed in the elastic member 8 for penetrating the screw member 3 has a sufficiently large diameter with respect to the screw member 3 and does not come into sliding contact with the outer diameter of the screw member 3. It had been.

At the front end and the rear end of the movement stroke of the seat side rail 2 with respect to the vehicle body side rail 1, the movement is stopped by a mechanical engagement relationship. That is, at the rear end of the movement stroke of the seat side rail 2, the movement is stopped by the collision of the gearbox 3 with the front end surface portion of the housing 6, while at the front end of the movement stroke, the bearing is provided at the rear end surface portion of the housing 6. The movement was set to stop when the members 4 collide.

[0005]

However, in such a conventional technique, the nut member 7 and the housing 6 have a backlash between the nut member 7 and the screw member 5 even when the screw member 5 is stopped. As a result, it is possible to make slight movements without any resistance, and this slight movement causes a so-called rattling feeling of the seat (discomfort felt by the seated person due to slight movement of the seat). There was a problem that the sitting feeling was impaired.

When the seat-side rail 2 stops at the front and rear ends of the stroke, the front and rear end surfaces of the housing 6, which is a rigid body, collides with a gear box or the like, which is also a rigid body. The impact due to such a collision is also transmitted to the seat side and gives an unpleasant feeling to the seated person, so that there is a problem that a good seated feeling of the seated person is impaired.
The applicant has previously proposed a device as shown in Japanese Patent Application No. 4-67007 as a technique capable of buffering the shock due to such a mechanical engagement relationship.

In this device, elastic cushioning bodies are respectively fitted to the screw members on the front side and the rear side of the nut member, and the nut members are elastically contacted at the front end and the rear end of the moving stroke of the nut member. is there. According to this
Although the impact of the seat can be mitigated when stopping at the front end and the rear end of the stroke, it is necessary to separately dispose the elastic shock absorbers before and after the nut member. Therefore, the number of parts is increased and the number of assembling steps is increased, and there is a possibility that cost reduction cannot be sufficiently achieved.

The present invention has been made by paying attention to the problems of the prior art as described above, and eliminates the rattling feeling of the seat, and the front and rear ends of the stroke without increasing the cost. The impact of the seat when stopping at
An object of the present invention is to provide a seat slide device capable of further improving the seating feeling without giving discomfort to the seated person.

[0009]

SUMMARY OF THE INVENTION The gist of the present invention for achieving such an object is to provide a rail (2) on a vehicle body side.
0) and a seat side rail (30) that is fitted to the vehicle body side rail (20) so as to be movable back and forth and supports the seat (B), and the seat side rail is provided via a drive unit (40). (30)
In the power seat slide device (10) for adjusting the front-rear position of the seat (B) by moving the vehicle back and forth by an electric motor (45), the drive unit (40) includes the vehicle body side rail (20) or the seat side. A screw member (41) rotatably supported by one of the rails (30) and rotationally driven by the electric motor (45), and openings (53, 54) through which the screw member (41) penetrates. Is formed to form the vehicle body side rail (20) or the seat side rail (3
0) a housing (50) fixed to the other one,
A nut member (42) fitted into the housing (50) by being rotatably engaged with the screw member (41), and through holes (63, 64) through which the screw member (41) passes. And the nut member (4
2) and an elastic member (60) interposed between the housing (50), and the peripheral edges of the through holes (63, 64) of the elastic member (60) have the openings (53, 54). ) Is formed with an annular protrusion (63a, 64a) penetrating the inside of the housing (50) and extending to the outside of the housing (50). The through holes (6
The power seat slide device (10) is characterized in that the inner periphery of the screw seat (41) is in sliding contact with the outer periphery of the screw member (41).

Further, the gist of the present invention from another point of view is that the vehicle body side rail (20) is fitted to the vehicle body side rail (20) so as to be movable back and forth to support the seat (B). A power seat which has a seat side rail (30) and which moves the seat side rail (30) back and forth by an electric motor (45) via a drive unit (40) to adjust the front and rear position of the seat (B). In the slide device (10), the drive part (40) is rotatably supported by one of the vehicle body side rail (20) and the seat side rail (30) and is rotated by the electric motor (45). A driven screw member (41) and openings (53, 54) through which the screw member (41) penetrates are formed to form the vehicle body side rail (2).
0) or the housing (50) fixed to the other of the seat side rails (30), and the screw member (41).
The housing (50) is rotatably screwed into the housing (50).
The nut member (42) fitted inside and the through holes (63, 64) through which the screw member (41) penetrates are formed to form the nut member (42) and the housing (5).
0) and an elastic member (60a) interposed therebetween,
A front end edge and a rear end edge of the elastic member (60a) respectively extend outside the housing (50) and extend along the outer wall surfaces of the front and rear end portions (51, 52) of the housing (6).
5, 66) are formed, and when the housing (50) collides with the stopper portions (43, 44) at the front and rear ends of the movement stroke of the nut member (42), the buffer portions (65, 66). The power seat slide device (10) is characterized by being arranged so as to make elastic contact with the stopper portions (43, 44).

Further, the gist of the present invention from another point of view is that the vehicle body side rail (20) is fitted to the vehicle body side rail (20) so as to be movable back and forth to support the seat (B). A power seat which has a seat side rail (30) and which moves the seat side rail (30) back and forth by an electric motor (45) via a drive unit (40) to adjust the front and rear position of the seat (B). In the slide device (10), the drive part (40) is rotatably supported by one of the vehicle body side rail (20) and the seat side rail (30) and is rotated by the electric motor (45). A driven screw member (41) and openings (53, 54) through which the screw member (41) penetrates are formed to form the vehicle body side rail (2).
0) or the housing (50) fixed to the other of the seat side rails (30), and the screw member (41).
The housing (50) is rotatably screwed into the housing (50).
The nut member (42) fitted inside and the through holes (63, 64) through which the screw member (41) penetrates are formed to form the nut member (42) and the housing (5).
0) and an elastic member (60b) interposed therebetween,
The peripheral edges of the through holes (63, 64) of the elastic member (60b) penetrate the inside of the openings (53, 54) and extend to the outside of the housing (50) with annular protrusions (63a, 64).
a), and the inner periphery of the through hole (63, 64) is formed by the screw member (63, 64) so as to generate a frictional resistance that alleviates a feeling of rattling due to a slight movement of the nut member (42) due to a backlash. 41) is in sliding contact with the outer periphery of the housing, and the front and rear edges of the elastic member (60b) extend outside the housing (50) to extend from the front and rear ends (51, 52) of the housing. The buffer member (65, 66) along the outer wall surface is formed, and the nut member (4
At the front and rear ends of the moving stroke of 2), the housing (5
0) collides with the stopper portion (43, 44), the buffer portion (65, 66) is arranged so as to make elastic contact with the stopper portion (43, 44). Exist in.

[0012]

When the power seat slide device (10) is assembled, the nut member (4) which constitutes the drive section (40) is installed.
An elastic member (60) having a through hole (63, 64) through which the screw member (41) penetrates is interposed between the housing 2 (2) and the housing (50). This elastic member (60, 6
0b) through holes (63, 64) have peripheral edges penetrating through the openings (53, 54) of the housing (50) and extending to the outside of the housing (50).
When forming a ring, the annular protrusions (63a, 64a)
The inner periphery of the through hole (63, 64) including the inner side of the is slidably contacted with the outer periphery of the screw member (41).

Therefore, in a state where a part of the elastic member (60) is supported by the peripheral edges of the openings (53, 54) of the housing (50), the screw member (4) has a large area.
It comes into contact with 1). As a result, an appropriate frictional resistance is generated between the elastic member (60) and the screw member (41), and the nut member (42) and the housing (50) relative to the screw member (41). Appropriate resistance will be added to such movement (that is, movement of the seat (B) back and forth). Therefore, even when the seat (B) slightly moves by the amount of backlash between the nut member (42) and the screw member (41), the slight movement becomes a gentle movement and the rattling sensation does not occur, and the seated person is uncomfortable. I don't feel pleasant.

When the screw member (41) is rotationally driven by the electric motor (45), the screw member (4)
The nut member (42) and the housing (50) move relative to each other along the longitudinal direction of (1), so that the seat side rail (30) is different from the vehicle body side rail (20) installed on the vehicle body side (A). ) Moves relative to the front-back direction and the seat (B)
The front and rear positions of are adjusted.

When the housing (50) collides with the stopper portions (43, 44) at the front end and the rear end of the movement stroke of the nut member (42), the movement of the nut member (42) is restricted, but the elasticity is reduced. Member (60a, 6
0b) has a front edge and a rear edge, respectively.
0) extending outwardly of the housing (50) to form buffer portions (65, 66) along the front and rear ends of the housing (50), the front and rear ends (51, 52) of the housing (50) are stopper portions (51, 52). 43, 44) does not directly collide with each other, but the cushioning portions (65, 66) of the elastic member (60) disposed therebetween make elastic contact with the stopper portions (43, 44).

Thereby, the buffer member (65) is provided between the nut member (42) and the housing (50) between the nut member (42) and the stopper portion (43) provided at one end of the screw member (41) at the front end of the moving stroke. ) Is inserted and stopped by making elastic contact. Therefore, since the impact force at the time of stopping is absorbed by the degree of bending of the cushioning portion (65), it is hard to feel as a physical sensation and the seated person does not feel discomfort.

At the rear end of the moving stroke as well, a buffer portion (66) is sandwiched between the housing (50) and the stopper portion (44) provided at the other end of the screw member (41). Comes into elastic contact and stops while absorbing the shock. In this way, the elastic members (60a, 60b)
By using the front and rear edges as the buffer portions (65, 66), it is possible to eliminate the uncomfortable impact at the time of stop without increasing the number of parts.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show a first embodiment of the present invention. However, FIGS. 6 and 7 are common to the other embodiments. As shown in FIG. 6, a seat B is mounted on a vehicle body floor A via a power seat slide device 10 so that the front-rear position can be adjusted. The power seat slide device 10 is
It has a pair of rail units 20a, 20a which are respectively arranged below both side portions of the seat B and extend in the front-rear direction. Each rail unit 20a has a leg member 1 on the vehicle body floor A.
The vehicle body side rail 20 is fixedly installed via the terminals 2 and 13, and the seat side rail 30 is fitted to the vehicle body side rail 20 so as to be movable back and forth and directly supports the seat B.

As shown in FIG. 7, the vehicle body side rail 20 is formed in a groove-shaped cross section having an open upper side, and has a bottom surface portion 21 and both side wall portions 22 and 22. On the other hand, the seat side rail 30 is formed in a groove-shaped cross section that opens downward and has a ceiling portion 31 and side wall portions 32, 32. A drive unit 40 for moving the seat side rail 30 back and forth with respect to the vehicle body side rail 20 is provided in a space formed between the vehicle body side rail 20 and the seat side rail 30.

The drive unit 40 is rotatably supported by the seat side rail 30 and is screwed into a screw member 41 which is rotatably driven by an electric motor 45 so as to be relatively rotatable with respect to the screw member 41. And a nut member 42 that is fitted in a housing 50 that is fixedly installed in the housing 20. The electric motor 45 is attached to the side wall portion 32 of the one seat side rail 30, and the rotational force of the output shaft is generated by the flexible shaft 46.
It is also transmitted to a gear box 43 installed inside the vehicle.

As shown in FIG. 1, the housing 50 into which the nut member 42 is fitted is molded from a material having rigidity such as metal, and has a box shape with an open upper side as shown in the drawing. . The front and rear end portions 51 and 52 of the housing 50 are provided with openings 53 and 54, respectively, through which a screw member 41, which will be described later, penetrates. As shown in FIG. 7, the housing 50 is fixed to the vehicle body-side rail 20 so that it cannot move back and forth and cannot rotate because the bottom portion 55 is screwed to the bottom surface portion 21 of the vehicle body-side rail 20.

An elastic member 60 is interposed between the nut member 42 and the housing 50. The elastic member 60 is
For example, it is made of a material having elasticity such as rubber or soft resin, and as shown in FIGS. 2 to 5, it is a box-shaped member having a shape similar to the housing 50 as a whole.
The front and rear end portions 61 and 62 of the elastic member 60 are provided with through holes 63 and 64 through which the screw member 41 passes.

The peripheral edge of the through hole 63 at the front end 61 of the elastic member 60 extends into the opening 53 of the housing 50 to form an annular projection 63a. In addition, the peripheral edge of the through hole 64 in the rear end portion 62 of the elastic member 60 also includes the housing 5
An annular protrusion 64a is formed by extending into the zero opening 54. As shown in FIG. 5, the annular projection 64a has an L-shaped cross section in which the tip edge side is bent along the front end surface portion 51 of the housing 50, which will be described later.

Through holes 63, 6 of such elastic member 60
As shown in FIG. 1, the inner circumference of 4 is provided with a frictional resistance (of a size that does not hinder the movement of the seat) that relieves the feeling of backlash caused by the slight movement of the nut member 42 due to the backlash. As shown in FIG. 7, the front end of the screw member 41 is rotatably seated on the seat side rail via a gear box 43 that is a speed reduction mechanism. The rear end portion of the screw member 41 is supported by the ceiling portion 31 of 30 and is also rotatably supported by the ceiling portion 31 via a bearing member 44.

As shown in FIG. 9, a worm 47 and a worm wheel 48 that meshes with the worm 47 are internally provided in the gear box 43. The parts are integrally solidified. The front end of the ceiling 31 of the seat-side rail 30 is raised to form a storage room for storing the gearbox 43.

Next, the operation of the first embodiment will be described.
In FIG. 7, when the electric motor 45 is started, its rotational force is transmitted to the screw member 41 via the flexible shaft 46 and the gear box 43, and the screw member 41 is rotationally driven.

The nut member 42 is fixedly mounted on the vehicle body side rail 20 by being fitted into the housing 50 screwed to the bottom surface portion 21 of the vehicle body side rail 20. When the screw member 41 rotates, the nut member 42 is moved in the longitudinal direction thereof. Along the nut member 42 moves relatively forward or backward. Therefore, as shown in FIG. 6, the rail units 20 forming a pair on both sides.
The seat B supported by the seat side rails 22 and 22 of a and 20a moves in the front-rear direction, and the front-rear position on the vehicle body floor A is adjusted.

And, the power seat slide device 1
0, when assembled, the nut member 42 and the housing 50
Through hole 6 through which the screw member 41 penetrates
The elastic member 60 in which 3, 64 are formed is interposed. The peripheral edges of the through holes 63, 64 of the elastic member 60 are
The annular protrusions 63a and 64a are formed so as to extend to the outside of the housing 50 by penetrating the openings 53 and 54 of the through holes 63 and 6 including the inside of the annular protrusions 63a and 64a.
The inner circumference of 4 is in sliding contact with the outer circumference of the screw member 41.

Therefore, the vicinity of the peripheral edges of the through holes 63 and 64, which are a part of the elastic member 60, is the opening 5 of the housing 50.
The screw member 41 is contacted with a wide area while being supported within the peripheral edges of the screws 3, 54. As a result, an appropriate frictional resistance is generated between the elastic member 60 and the screw member 41, and an appropriate resistance to the relative movement of the nut member 42 and the housing 50 with respect to the screw member 41 (that is, the front-back movement of the seat B). Will be added. Therefore, even when the seat B slightly moves by the amount of the backlash between the nut member 42 and the screw member 41, the slight movement causes a gradual movement and the rattling feeling does not occur, and the sitting feeling of the seated person is further improved. Can be improved.

8 and 9 show a second embodiment of the present invention. In the present embodiment, the elastic member 60a interposed between the nut member 42 of the drive unit 40 and the housing 50.
However, it is different from the elastic member 60 of the first embodiment.
The same parts as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted.

As shown in FIG. 8, the elastic member 60a is formed of a material having elasticity such as rubber or soft resin into a box-like shape similar to the housing 50, as in the first embodiment. . The front and rear end portions 61 and 62 of the elastic member 60a are provided with through holes 63 and 64 through which the screw member 41 passes. Further, the front end edge of the front end portion 61 of the elastic member 60 extends to the outside front side of the housing 50, and forms a buffer portion 65 along the outer wall surface of the front end portion 51 of the housing 50. Similarly, the rear end edge of the rear end portion 62 of the elastic member 60 extends outward and rearward of the housing 50 and forms a buffer portion 66 along the outer wall surface of the rear end portion 52 of the housing 50.

The thickness of each buffer portion 65, 66 is set to such a thickness that the outer wall surfaces of the front and rear end portions 51, 52 of the housing make elastic contact at the front end and the rear end of the moving stroke of the nut member 42. Further, the buffer portions 65 and 66 are provided with insertion holes 67 and 68 corresponding to the through holes 63 and 64, respectively, into which the screw member 41 is inserted.

As shown in FIG. 9, at the front end of the movement stroke of the nut member 42, the buffer portion 65 is sandwiched between the front end portion 51 of the housing 50 and the end surface (stopper portion) of the gear box 43, and at the time of stopping. At the rear end of the stroke, which absorbs impact, the rear end portion 52 of the housing 50 and the bearing member 4
A cushioning portion 66 is sandwiched between the end face 4 (stopper portion) and arranged so as to absorb a shock at the time of stop.

Next, the operation of the second embodiment will be described.
As shown in FIG. 9, at the front end of the movement stroke of the nut member 42 with respect to the screw member 41 (the rearmost position of the seat B), the end surface (stopper portion) of the gear box 43 collides with the front end portion 51 side of the housing 50. Thus, the relative forward movement of the nut member 42 is forcibly restricted.
Further, the rear end of the movement stroke of the nut member 42 (seat B
At the frontmost position), the relative rearward movement of the nut member 42 is forcibly restricted by the end surface (stopper portion) of the bearing member 44 colliding with the rear end portion 52 side of the housing 50.

As described above, when the housing 50 collides with the stopper portion such as the end surface of the gear box 43 at the front end and the rear end of the moving stroke of the nut member 42, the front and rear end portions 51 and 52 of the housing 50 directly contact the stopper portion. Instead of colliding, the cushioning portions 65 and 66 of the elastic member 60 arranged between them make elastic contact with the stopper portion.

As a result, the nut member 42 and the housing 50 are moved toward the screw member 4 at the front end of the moving stroke.
The cushioning portion 65 is sandwiched between the gearbox 43 and the gearbox 43 that supports the front end side of No. 1 and elastically stops. Therefore,
Since the impact force at the time of stopping is absorbed by the degree of bending of the buffer portion 65, it is hard to feel as a physical sensation and the seated person does not feel discomfort.

Similarly, at the rear end of the moving stroke as well, the housing 50 makes elastic contact with the bearing member 44 supporting the rear end side of the screw member 41 so as to sandwich the cushioning portion 66, and stops while absorbing the shock. To do. in this way,
By using the front and rear edges of the elastic member 60a as the cushioning portions 65 and 66, it is possible to eliminate an unpleasant impact at the time of stop without increasing the number of parts and the number of assembling steps, and it is possible to achieve a sufficient cost reduction. it can. Also, the screw member 4
1 has not only the inner circumferences of the through holes 63 and 64 of the elastic member 60a but also the insertion holes 67 and 68 of the respective cushioning portions 65 and 66.
The inner circumference is also in sliding contact. Therefore, since the frictional resistance of the elastic member 60a with respect to the screw member 41 is increased, the rattling feeling can be suppressed.

10 and 11 show a third embodiment of the present invention. In this embodiment, the elastic member 60b interposed between the nut member 42 and the housing 50 is provided with both the annular protrusions 63a and 64a in the first embodiment and the buffer portions 65 and 66 in the second embodiment. It was formed.
Thereby, in this embodiment, one elastic member 60b is used.
As a result, the actions and effects of the above-described first and second embodiments can be achieved.

As shown in FIG. 5, the annular projection of the elastic member is formed in an L-shaped cross section with its tip edge side bent along the outer wall surface of the front end of the housing, and has a wider area. By arranging along the outer wall surface of the front end portion, the buffer portion can be used on the tip side of the annular projection. In addition, the present invention is not limited to the various embodiments shown in the drawings, but has various aspects. For example, an electric motor, a gear box, a screw member, etc. are attached to the vehicle body side rail side, and a nut member, a housing, etc. It may be fixed to.

[0040]

According to the power seat slide device of the present invention, an annular protrusion is formed on the peripheral edge of the through hole of the elastic member interposed between the nut member that constitutes the drive section and the housing, and the through hole of the through hole is formed. Since the inner circumference is slidably contacted with the outer circumference of the screw member, the unpleasant rattling feeling of the seat due to the slight movement of the backlash between the nut member and the screw member can be eliminated, and the sitting feeling of the seated person can be improved. Can be improved.

Further, cushioning portions are formed along the front and rear end portions of the housing at the front end edge and the rear end edge of the elastic member, respectively, and the cushioning portions are arranged so as to elastically contact the stopper portion at the front and rear ends of the moving stroke of the nut member. Since it has been installed, without increasing the cost without increasing the number of components, the impact of the seat at the time of stopping at the front end and the rear end of the stroke of the nut member is alleviated and eliminated so that the seated person does not feel uncomfortable. The sitting feeling can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a peripheral configuration of a nut member of a power seat slide device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a front end side of an elastic member of the power seat slide device according to the first embodiment of the invention.

FIG. 3 is a cross-sectional view showing a front end side of an elastic member of the power seat slide device according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing a rear end side of an elastic member of the power seat slide device according to the first embodiment of the present invention.

FIG. 5 is a sectional view showing a rear end side of an elastic member of the power seat slide device according to the first embodiment of the present invention.

FIG. 6 is a perspective view showing a seat supported by the power seat slide device according to the first embodiment of the present invention.

FIG. 7 is an exploded perspective view showing the overall configuration of the power seat slide device according to the first embodiment of the present invention.

FIG. 8 is an exploded perspective view showing a peripheral configuration of a nut member of a power seat slide device according to a second embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view showing one rail unit of the power seat slide device according to the second embodiment of the present invention.

FIG. 10 is a sectional view showing a peripheral structure of a nut member of a power seat slide device according to a third embodiment of the present invention.

FIG. 11 is a perspective view showing the front end side of the elastic member of the power seat slide device according to the third embodiment of the present invention.

FIG. 12 is a vertical cross-sectional view showing one rail unit of a conventional power seat slide device.

FIG. 13 is an exploded perspective view showing a peripheral configuration of a nut member in a conventional power seat slide device.

[Explanation of symbols]

 B ... Seat 10 ... Power seat slide device 20 ... Car body side rail 30 ... Seat side rail 40 ... Drive part 46 ... Electric motor 40 ... Drive part 41 ... Screw member 42 ... Nut member 46 ... Electric motor 50 ... Housing 53, 54 ... Opening portion 60 ... Elastic member 63, 64 ... Through hole 63a, 64a ... Annular projection 65, 66 ... Buffer portion

Claims (3)

[Claims] 1. A vehicle body side rail, and a seat side rail that is fitted to the vehicle body side rail so as to be movable back and forth to support a seat, and the seat side rail is moved back and forth by an electric motor via a drive unit. In the power seat slide device for adjusting the front-back position of the seat, the drive unit is rotatably supported by one of the vehicle body side rail and the seat side rail, and is rotationally driven by the electric motor. A screw member, a housing in which an opening through which the screw member penetrates is formed and which is fixedly provided on the other of the vehicle body side rail or the seat side rail, and screwed rotatably relative to the screw member. A nut member fitted into the housing; and an elastic member having a through hole through which the screw member penetrates and interposed between the nut member and the housing. The elastic member has a peripheral edge of a through hole that forms an annular protrusion that penetrates through the opening and extends to the outside of the housing, and reduces friction caused by slight movement of the nut member due to backlash. A power seat slide device, wherein an inner periphery of the through hole is in sliding contact with an outer periphery of the screw member so as to generate resistance. 2. A vehicle body side rail, and a seat side rail which is fitted to the vehicle body side rail so as to be movable back and forth to support a seat, and the seat side rail is moved forward and backward by an electric motor via a drive unit. In the power seat slide device for adjusting the front-back position of the seat, the drive unit is rotatably supported by one of the vehicle body side rail and the seat side rail, and is rotationally driven by the electric motor. A screw member, a housing in which an opening through which the screw member penetrates is formed and which is fixedly provided on the other of the vehicle body side rail or the seat side rail, and screwed rotatably relative to the screw member. A nut member fitted into the housing; and an elastic member having a through hole through which the screw member penetrates and interposed between the nut member and the housing. A front end edge and a rear end edge of the elastic member respectively extend outward of the housing to form buffer portions along outer wall surfaces of front and rear end portions of the housing, and front and rear ends of a moving stroke of the nut member. In the power seat slide device, the buffer portion is arranged so as to elastically contact the stopper portion when the housing collides with the stopper portion. 3. A vehicle body side rail, and a seat side rail which is fitted to the vehicle body side rail so as to be movable back and forth to support a seat, and the seat side rail is moved forward and backward by an electric motor via a drive unit. In the power seat slide device for adjusting the front-back position of the seat, the drive unit is rotatably supported by one of the vehicle body side rail and the seat side rail, and is rotationally driven by the electric motor. A screw member, a housing in which an opening through which the screw member penetrates is formed and which is fixedly provided on the other of the vehicle body side rail or the seat side rail, and screwed rotatably relative to the screw member. A nut member fitted into the housing; and an elastic member having a through hole through which the screw member penetrates and interposed between the nut member and the housing. The elastic member has a peripheral edge of a through hole that forms an annular protrusion that penetrates through the opening and extends to the outside of the housing, and reduces friction caused by slight movement of the nut member due to backlash. The inner periphery of the through hole is in sliding contact with the outer periphery of the screw member so as to generate resistance, and the front end edge and the rear end edge of the elastic member respectively extend outside the housing and extend in front of and behind the housing. A buffer portion is formed along the outer wall surface of the end portion, and the buffer portion is arranged so as to elastically contact the stopper portion when the housing collides with the stopper portion at the front and rear ends of the moving stroke of the nut member. Power seat slide device characterized by: