JPH08300984A - Nut structure for feed screw - Google Patents

Abstract

PURPOSE: To provide a nut structure for a feed screw capable of being adapted to any large lead screw, and easy in manufacturing. CONSTITUTION: A screw tooth 4a formed on a part of a nut capable of being screwed with a feed screw is formed on at least one nut member 4, and the nut member 4 is fixed to a casing 6 to be screwed with the feed screw.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut structure for a feed screw, and more particularly to a nut structure that can be screwed with a lead screw having a large lead.

[0002]

2. Description of the Related Art Generally, a vehicle seat slide device includes a pair of lower rails fixed to a vehicle body and a pair of upper rails slidably mounted on the lower rails and on which a seat is placed.

Among the vehicle seat slide devices, the one in which the seat is manually slid is equipped with a manual lock device for fixing the seat at a predetermined position, which is swingably attached to one of the upper rails for operation. The seat is fixed by fitting a lock member operated by a lever and a latch plate attached to one of the lower rails.

On the other hand, in the structure in which the seat is slid electrically, a slide screw rotatably attached to one of the upper rails and a slide nut fixed to one of the lower rails are screwed together to form a slide screw. The seat is moved to a predetermined position by rotating the motor with an electric motor. In this configuration, the leads of the slide screw and the screw of the slide nut are smaller than the friction angle, and even if a force in the vehicle front-rear direction is applied to the slide nut due to a collision of the vehicle, the seat does not move in the front-rear direction, Therefore, it is not necessary to provide a lock device.

The inventor of the present application makes a study for applying to a vehicle seat slide device or a seat reclining device equipped with a manual lock device by making the lead of the slide screw and the slide nut screw larger than the friction angle. I have been earnestly repeating.

[0006]

However, it is difficult to manufacture a screw and a nut with a large lead because the amount of advance per rotation is large in tapping (thread cutting).
There is a problem in that it is particularly difficult to manufacture a nut that requires the formation of screw teeth on the inner surface.

The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide a nut structure for a feed screw which can accommodate any large lead screw and is easy to manufacture. Has an aim.

[0008]

In order to achieve the above object, a nut structure for a feed screw according to the present invention comprises at least one nut having screw teeth formed in a part of the nut that can be screwed with the feed screw. A member and a casing that accommodates the nut member are provided, and the nut member is fixed to the casing so that the nut screw can be screwed into the feed screw.

It is effective to apply a nut member having a screw lead having a friction angle larger than the friction angle to the above structure.

An elastic body may be interposed between the nut member and the casing.

The nut member may be fixed to the casing by attaching a pressing member to the casing from above the nut member.

An elastic body may be interposed between the nut member and the pressing member.

[0013]

Since at least one nut member having screw teeth formed on a part of the nut that can be screwed with the feed screw is fixed to the casing, the feed screw is inserted into the casing and screwed with the nut member. The member acts as a nut.

Instead of a large lead nut, which is difficult to manufacture,
The above nut structure can be adopted.

When an elastic body is interposed between the nut member and the casing, not only the resistance due to the twist of the nut member with the feed screw is reduced and rattling is eliminated, but also the vibration of the nut member is damped.

When the nut member is fixed to the casing by the pressing member, the shape of the casing is simplified.

When an elastic body is interposed between the nut member and the pressing member, resistance due to twisting of the nut member with the feed screw is reduced to eliminate backlash, and also vibration of the nut member is attenuated. .

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a feed screw nut structure 2 according to a first embodiment of the present invention, which is composed of four rectangular parallelepiped nut members 4 and a cylindrical casing 6 in which the nut members 4 are housed.

On the inner surface of each nut member 4, there are formed screw teeth 4a formed on a part of four feed screw nuts, and on the outer surface thereof, for fixing the nut member 4 to the casing 6. A plurality of (two in FIG. 1) screw holes 4b are formed.

On the other hand, inside the casing 6, feed screw insertion holes 6a are formed concentrically with the vertical axis of the casing 6, and are arranged parallel to the vertical axis of the casing 6 at intervals of 90 degrees.
A book groove 6b is formed along the feed screw insertion hole 6a. The casing 6 also has a plurality of (two in FIG. 1) screw holes 6c formed along each groove 6b.
After inserting the nut member 4 into the screw hole 6, the screw 8 is inserted into the screw hole 6 and screwed into the screw hole 4b of each nut member 4, whereby the nut member 4 is fixed to the casing 6.

When a feed screw (not shown) is inserted into the nut structure 2 having the above construction and gradually rotated, the feed screw and the screw teeth 4a of each nut member 4 are screwed together, and the nut structure 2 as a whole. Acts as a nut for the feed screw.

In the above structure, each nut member 4 has screw teeth corresponding to the four-threaded screw, and the four nut members 4 are attached at 90 degree (360 degree / 4) intervals. It is only necessary to form the same screw teeth on all of 4 and arrange the ends so as to match each other.

FIG. 2 shows a modified example 2A of the nut structure 2 of FIG. 1, in which five nut members 4 having screw teeth corresponding to the five-thread screw and five nut members 4 in which the nut members 4 are housed. And a cylindrical casing 6A having a groove 6b. Also in this configuration, each nut member 4 has screw teeth corresponding to the five-thread screw, and since the five nut members 4 are attached at 72 degree (360 degree / 5) intervals, The same screw teeth may be formed on all of them and the ends may be aligned with each other. Other configurations and operations are the same as those of the embodiment shown in FIG. 1, and the description thereof will be omitted.

FIG. 3 shows a nut structure 12 for a feed screw according to a second embodiment of the present invention, in which four nut members 14 having a tapered cross section and a casing 16 for accommodating the nut members 14 are provided. Is equipped with.

On the inner surface of each nut member 14, screw teeth 14a formed in a part of the nut for the feed screw are formed, while inside the casing 16, the feed screw is concentric with the vertical axis of the casing 16. The insertion holes 16a are formed, and four tapered grooves 16b are formed in parallel with the vertical axis of the casing 16 at intervals of 90 degrees along the feed screw insertion holes 16a.

In the case of this nut structure 12, the nut member 1
4 and the groove 16b of the casing 16 are formed in a tapered shape, the nut structure 2, 2A of FIG.
The fixing screw 8 used in No. is not necessary, but the nut member 14
After being accommodated in the groove 16b of the casing 16, the two covers 18 having the feed screw insertion holes 18a are attached to the casing 16
The nut member 14 is retained inside the casing 16 by being screwed to both ends of the casing 16.

FIG. 4 shows a modification 12 of the nut structure 12 of FIG.
3A shows the nut structure 12 of FIG. 3 in which a flat plate-shaped elastic body 20 is interposed between the nut member 14 and the groove 16b of the casing 16. By providing the elastic body 20, not only resistance due to twisting of the feed screw and nut can be reduced, but also abnormal noise due to rattling or operating noise due to vibration damping can be reduced.

FIG. 5 shows a nut structure 22 for a feed screw according to a third embodiment of the present invention, which comprises a rectangular parallelepiped nut member 24 and a rectangular parallelepiped casing 26 in which the nut member 24 is housed. Become.

On the inner surface of the nut member 24, screw teeth 24a formed on a part of the feed screw nut are formed, while on the casing 26, a feed screw insertion hole 26a is formed concentrically with the vertical axis of the casing 26. And a rectangular accommodating hole 26b is formed in parallel with the longitudinal axis of the casing 26 along the feed screw insertion hole 26a.

In the configuration shown in FIG. 5, the nut member 24
Is inserted into the rectangular accommodation hole 26b, and then the pressing plate 30 is screwed onto the casing 26 from above the nut member 24, whereby the nut member 24 is inserted into the rectangular accommodation hole 26 of the casing 26.
Retained inside.

FIG. 6 shows a modification 22 of the nut structure 22 of FIG.
5A, in the nut structure 22 of FIG. 5, a rectangular groove 24b is formed on the upper surface of the nut member 24A, the elastic body 32 is attached to the rectangular groove 24b, and the elastic body 3 is formed.
The pressing plate 30 is screwed to the casing 26 from above 2.

5 and 6, the nut members 24 and 24A are tapered as shown in FIG. 3 or 4, and the nut member receiving hole 26b of the casing 26 is also tapered. It can also be formed. In this case, insert the feed screw into the feed screw insertion hole 26a.
Even when the nut member is not inserted into the housing, the nut member is securely held in the accommodation hole.

In FIGS. 5 and 6, one nut member is provided, but a plurality of nut members may be provided, and the number of nut members is appropriately determined according to the axial force applied to the nut structure. It

The above-described nut structure according to the present invention can be applied not only to a vehicle seat slide device or a seat reclining device but also to other applications, and is used as a substitute for a large lead nut which is difficult to manufacture. Can be used.

[0035]

Since the present invention is configured as described above, it has the following effects.

Since the simple construction is such that at least one nut member having screw teeth formed on a part of the nut which can be screwed with the feed screw is fixed to the casing, the feed screw can be easily manufactured. The meshing portion with and is reduced, and biting due to twisting can be prevented.
As a result, operating noise is reduced and efficiency is improved.

Any large lead screw, including a lead screw whose screw lead has a larger friction angle, can be easily accommodated.

When an elastic body is interposed between the nut member and the casing, resistance due to twisting of the nut member with the feed screw is reduced, abnormal noise due to guttering is reduced, and vibration is dampened. The sound is reduced.

When the nut member is fixed to the casing with the pressing member, the shape of the casing is simplified and can be easily manufactured.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a nut structure for a feed screw according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of a modified example of the nut structure of FIG.

FIG. 3 is an exploded perspective view of a feed screw nut structure according to a second embodiment of the present invention.

FIG. 4 is an exploded perspective view of a modified example of the nut structure of FIG.

FIG. 5 is an exploded perspective view of a feed screw nut structure according to a third embodiment of the present invention.

FIG. 6 is an exploded perspective view of a modified example of the nut structure of FIG.

[Explanation of symbols]

 2,2A, 12,12A, 22,22A Nut structure 4,14,24 Nut member 4a, 14a, 24a Screw tooth 6,6A, 16,26 Casing 6a, 16a, 26a Feed screw insertion hole 6b, 16b Nut member accommodation Groove 18 Cover 26b Nut member accommodation hole 30 Holding plate 20, 32 Elastic body

Claims (5)

[Claims] 1. A nut structure capable of being screwed with a feed screw, wherein at least one nut member having screw teeth formed on a part of the nut screwable with the feed screw, and the nut member being housed. A nut structure for a feed screw, which is configured to be screwed with the feed screw by fixing the nut member to the casing. 2. The feed screw nut structure according to claim 1, wherein the lead of the screw of the nut member is larger than the friction angle. 3. The feed screw nut structure according to claim 1, wherein an elastic body is interposed between the nut member and the casing. 4. The nut structure for a feed screw according to claim 1, wherein the nut member is fixed to the casing by attaching a pressing member to the casing from above the nut member. 5. The nut structure for a feed screw according to claim 4, wherein an elastic body is interposed between the nut member and the pressing member.