JPH10113838A - Stopper of ball screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent positional slippage in the collisional direction at the time of collision of a moving article by providing a spiral projection to closely screw in a thread groove of a ball screw on a ball screw fitting surface of a split fastening stopper. SOLUTION: When a motor is driven and a screw transmission gear works, a slide unit moves on a ball screw 6 by a screw transmission, and when it moves to a terminal end, an end surface of the slide unit collides against a side surface of a stopper 8 and stops. At this time, the stopper 8 receives impact in the collisional direction, but as a spiral projection 3 of the stopper 8 is closely screwed in a thread groove 7 of the ball screw 6, no positional slippage in the collisional direction is caused by the impact. Additionally, no local load is generated on the stopper 8 and no breakage is caused on the stopper 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stopper for a ball screw provided at an end of a ball screw of a screw transmission device.

[0002]

2. Description of the Related Art Conventionally, a screw transmission device using a ball screw has been known as a driving means for converting a rotary motion into a linear motion. A screw transmission device is used for a feed mechanism of a machine tool or the like.A stopper for restricting the movement of the moving object in the axial direction is provided at a screw shaft end as a means for forcibly stopping the moving object moved by the ball screw. Is provided.

As a stopper of this type, a block type stopper fixed on a linear moving path of a moving object and a split stopper fixed on a ball screw 6 and rotating simultaneously with the ball screw as shown in FIG. It is roughly divided into a tightening type stopper. However, for the former block type stopper, it is necessary to machine a mounting hole or provide a rail so that the stopper can move to any position when changing the moving range of a moving object that moves linearly However, there is a problem in terms of simplicity of adjustment and manufacturing cost.

In the latter type, the frictional force between the outer peripheral surface of the feed screw and the inner surface of the stopper causes the frictional force.
Although it counters the impact force at the time of collision of moving objects, due to the friction coefficient of the contact surface and the variation in the tightening force of the split screw,
The resistance in the collision direction is not stable, causing a shift in the stop position,
In some cases, a moving object cannot be accurately braked during a collision. Furthermore, in the latter type of the split tightening type, the stopper rotates simultaneously with the feed screw due to its structure, which causes an inertial load on the drive source and requires a reduction in the weight of the stopper.
As described above, the tightening force of the split screw is required.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a stopper for a ball screw stopper which can easily change the installation position of the stopper and has a small inertial load on a driving source.

[0006]

SUMMARY OF THE INVENTION A ball screw stopper according to the present invention is a split tightening stopper that fits into a ball screw to restrict the movement of a moving object in the axial direction. The surface is provided with a helical projection which is screwed closely into the thread groove of the ball screw.

According to the present invention, since the spiral projection of the stopper is closely screwed into the thread groove of the ball screw, no displacement occurs in the collision direction when the moving object collides.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a split tightening stopper that fits into a ball screw to restrict the movement of a moving object in the axial direction. A spiral projection is provided on the mating surface to be screwed into the screw groove of the ball screw. Since the spiral projection of the stopper is tightly screwed into the screw groove of the ball screw, the moving object In the event of a collision, the stopper does not shift in the collision direction, and the impact force received when colliding with a moving object is received by the helical projection of the ball screw, so no local load occurs and the stopper is damaged I will not do it.

The invention according to claim 2 is characterized in that a helical metal wire is fixed to the thread groove fitting surface of the synthetic resin split fastening stopper by insert molding to form a helical projection. The spiral metal wire is fixed to the stopper body made of synthetic resin by insert molding, so it can be manufactured at low cost without the need for machining, etc. By using it as a prototype of a molding die, it is possible to easily cope with changes in the thread diameter and lead of the thread groove.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In FIG. 1, a stopper 8 of the present invention is a split tightening stopper composed of an upper collar and a lower collar divided into an upper collar 1 and a lower collar 2. It is tightly fixed by a nut 5. On the ball screw fitting surface of the stopper 8, as shown in FIG. 2, spiral projections 3 tightly screwed into the screw grooves 7 of the ball screw 6 are formed at the same pitch as the screw pitch of the ball screw 6.

The stopper 8 having the above structure is mounted on the ball screw 6 and is fixed at a stop position of the screw transmission device. Next, the operation of the present invention will be described with reference to FIG. In the figure, 9 is a base of a screw transmission device, 10 is a slide unit moved by a ball screw 6, and 11 is a motor. In the screw transmission device shown in the figure, a stopper 8 is mounted on a ball screw 6 and fixed at an appropriate position on a base 9.

When the motor 11 is driven and the screw transmission device is operated, the slide unit 10 moves on the ball screw 6 by screw transmission. When the slide unit 10 moves to the end, the end face of the slide unit 10 collides with the side surface of the stopper 8. Stop. At this time, the stopper 8 receives an impact in the collision direction, but since the helical projection 3 of the stopper 8 is tightly screwed into the screw groove 7 of the ball screw 6, the impact does not cause a displacement in the collision direction. .

Further, at the time of collision, the impact force applied to the stopper in the collision direction is received by the helical projection 3 of the ball screw 6, so that a local load is not applied to the stopper and the stopper is not damaged. FIG.
In another embodiment of the present invention, the split tightening stopper 8 is made of synthetic resin, and the helical metal wire 12 is fixed to the stopper body by insert molding.

In this embodiment, the helical metal wire can be processed by die-casting, so that the helical projection can be processed at low cost, and the ball screw can be used as the base of the molding die. It is possible to easily cope with changes in the thread diameter of the groove and the lead. FIG.
In another embodiment of the present invention, a stopper 8 having a spiral projection 3 is manufactured by sheet metal pressing.

[0015]

As described above, according to the present invention, since the helical projection of the stopper is closely screwed into the thread groove of the ball screw, the stopper is displaced in the collision direction when the moving object collides. Never. Further, the impact force received at the time of collision with the moving object is received by the helical projection screwed into the ball screw groove, so that a local load does not occur and the stopper is not damaged.

Further, since the spiral metal wire is fixed to the stopper body made of synthetic resin by insert molding,
It can be manufactured at low cost without the need for mechanical processing.Also, it is possible to easily change the thread diameter and lead of the thread groove by processing the metal wire by die casting and using the ball screw as the original mold. can do.

[Brief description of the drawings]

FIG. 1 is a sectional view of a stopper according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a state in which a stopper is engaged with a ball screw according to an embodiment of the present invention.

FIG. 3 is a schematic view of a screw transmission device according to an embodiment of the present invention.

FIG. 4 is a schematic view of a stopper according to another embodiment of the present invention.

FIG. 5 is a schematic view of a stopper according to another embodiment of the present invention.

FIG. 6 is a schematic view of a conventional stopper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper split collar 2 Lower split collar 3 Spiral projection 4 Bolt 5 Nut 6 Ball screw 7 Screw groove 8 Stopper 9 Base 10 Slide unit 11 Motor 12 Spiral metal wire

Claims (2)

[Claims] 1. A split tightening stopper that fits into a ball screw and restricts the movement of a moving object in an axial direction, and is spirally tightly screwed into a screw groove of the ball screw on a ball screw fitting surface of the split tightening stopper. A ball screw stopper characterized by having a projection. 2. A helical metal wire is fixed to a screw groove fitting surface of a synthetic resin split tightening stopper by insert molding to form a helical projection.
Ball screw stopper described.