JP4516048B2 - Squeegee with adjustable gap - Google Patents

Description

The present invention relates to a ball screw, and more particularly, to a squeegee capable of adjusting a clearance attached to an end of a ball screw nut.

  As shown in FIG. 1, the conventional ball screw has a squeegee 11 fitted on both ends of a nut 12 assembled to a screw shaft 10, and the squeegee 121 is fastened by a positioning screw element 121. Mainly prevents the intrusion of foreign matter and leakage of the lubricating oil by the convex edge 111, but in order to compensate for the processing error, a certain distance between the convex edge 111 of the squeegee 11 and the spiral groove 101 on the screw shaft 10 is fixed. If a gap (for example, 0.25 mm) is maintained and a production error is added, the gap becomes larger, but according to well-known data, if the particle size of the foreign material exceeds 0.17 mm, the ball screw will be damaged. Maintaining a gap of about 0.25 mm has no effect of preventing foreign material intrusion and lubricating oil leakage.

  In order to improve the shaving effect, the gap between the convex edge 111 of the squeegee 11 and the spiral groove 101 on the screw shaft 10 is made zero, and then the convex edge 111 of the squeegee 11 becomes the spiral groove 101 of the screw shaft 10. As a result, the frictional resistance is greatly increased, the working efficiency of the ball screw is significantly reduced, and there is a problem that a large amount of foreign matter accumulates at the contact portion between the squeegee 11 and the spiral groove 101.

  Therefore, the ball screw has been improved to the following two methods.

The first is proposed in US Pat. No. 6,571,653 B1 shown in FIG. This is because, as described above, the squeegee 13 prevents the intrusion of foreign matters and leakage of the lubricating oil by the convex edge 131, and is compressed in the radial direction by providing the annular spring 14 on the back surface of the convex edge 131. The frictional resistance is reduced by increasing the force and opening the cut edge 132 with one end closed on the convex edge 131.
However, according to such a cut end 132, the foreign matter accumulates rapidly on the cut end 132 as the squeegee 13 rotates (a large amount accumulates in the feed direction), and the foreign matter remains on the ball screw all the time. Since the friction resistance of the convex edge 131 is greatly increased by the annular spring 14, the working efficiency of the ball screw is greatly reduced.
In addition, the spring has a problem that it is gradually loosened due to elastic fatigue, and as a result, the effect of preventing the intrusion of foreign matter and the leakage of the lubricating oil gradually decreases.

Second, a product as shown in FIG. 3 has been proposed. The nut 15 positions the annular brush 17 by a C-shaped engagement ring 16, and the annular brush 17 serves as a squeegee.
However, the annular brush 17 eliminates problems such as excessive frictional resistance and maintenance of gaps. However, foreign matter cannot be prevented from entering, and when a ball screw is used for a long period of time, the foreign matter is removed from the nut 15 and the screw shaft. Intrudes between 18 and leaks a large amount of lubricating oil. Therefore, the operation of the ball screw becomes unstable.

  The main objective of this invention is to provide the squeegee which can adjust a clearance gap.

Another object of the present invention is to provide a squeegee that can reduce the frictional resistance of shaving and can effectively guide and discharge foreign matter.

The first invention of the present application made to achieve the above object is a squeegee that is assembled between a nut and a screw shaft and is installed in an annular groove on the inner peripheral surface of the nut. It is a member that can be bent in an annular shape having a maximum outer diameter larger than that of the inner peripheral surface annular groove of the nut, and an outer peripheral surface thereof is provided with a conical surface inclined to the inner peripheral surface annular groove of the nut. Has a slit that penetrates the shaving tooth portion on the back side, and a spiral shaving tooth portion that meshes with the spiral groove of a ball screw is provided on the back side of the squeegee, and the spiral shaving tooth portion and the spiral groove the gap between increases gradually from the inside of the nut of the squeegee to the outside of the nut of the squeegee, before Symbol helical scraping teeth, the end located inside the nut of the squeegee, the The squeegee said The end of the squeegee extends spirally to the end located outside the nut, and the width of the end located inside the nut of the squeegee is wider than the end located outside the nut of the squeegee, and from the inside The gist of the present invention is a squeegee with an adjustable gap, which is formed so as to gradually decrease outward .

In the second aspect of the invention, said one end of the conical surface of the squeegee is provided with a guide conical surface, the guide conical surface is characterized in that mesh with the helical groove of the nut, according to the first shot bright The gist is that the gap is adjustable.

In the third invention of the present application, the shape of the annular groove on the inner peripheral surface of the nut is any one of a cylindrical shape , a combination of a cylindrical shape and a conical shape , or a combination of two conical shapes. The gist of the invention is the squeegee capable of adjusting the clearance according to claim 1 or 2.

In the fourth aspect of the present invention, the cut groove has first through gap adjustable squeegee according to any one of the third invention is characterized in that opened obliquely toward the forming direction of the spiral grooves of the ball screw It is the gist.

According to the squeegee capable of adjusting the gap according to the present invention, the gap can be adjusted, and the frictional resistance of shaving can be reduced, and foreign matters can be effectively guided and discharged.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  First, FIG. 4 and FIG. 5 will be referred to. The squeegee 30 with adjustable gap according to the present invention includes one ball screw 20, two squeegees 30, and one nut 40. The squeegee 30 is assembled to the ball screw 20 according to the nut 40. Refer to FIGS. 6 and 7 for the structure of the nut and screw shaft.

  The ball screw 20 has a spiral groove 21 on the circumferential surface.

  The squeegee 30 is an annular member that is fitted to the ball screw 20, and a helical tooth portion 31 that meshes with the helical groove 21 of the ball screw 20 is provided on the back side thereof. The gap between the helical tooth portion 31 and the helical groove 21 gradually increases from the inside to the outside. Thereby, the width | variety of a helical cutting tooth part reduces gradually from an inner side to an outer side. A conical surface 32 is provided on the peripheral surface of the squeegee 30. A guide conical surface 33 is provided at one end of the conical surface 32. The conical surface 32 has a cut groove 34 penetrating the shaving tooth portion 31 on the back side, and the cut groove 34 is opened obliquely along the direction of the spiral groove 21 of the ball screw 20.

  The nut 40 is provided by being fitted to the ball screw 20. Inner circumferential surface annular grooves 42 are formed on the two end surfaces. The inner circumferential surface annular groove 42 corresponds to the conical surface 32 of the squeegee 30, and the inner circumferential surface annular groove 42 has an inner diameter smaller than the maximum outer diameter of the squeegee 30. The squeegee 30 is tightly fitted to the inner peripheral surface of the inner peripheral surface annular groove 42 at the conical surface 32, and the squeegee 30 is reduced in the radial direction by the cut groove 34. A positioning hole 41 is formed in the nut 40 in the radial direction, and the fixing screw 43 is fastened to the conical surface 32 of the squeegee 30 by the positioning hole 41. Then, the squeegee 30 is positioned (the amount of deformation in the radial direction is also fixed), and the shaving tooth portion 31 can be adjusted to a predetermined gap as requested by the user.

Next, the operation principle of the present invention will be described in detail with reference to the drawings. In order to reduce the gap between the squeegees, the squeegee 30 is positioned in the nut 40, and the squeegee 30 corresponds to the spiral groove 21 of the ball screw 20 at the shaving tooth portion 31. When the squeegee 30 is rotated, the squeegee 30 is tightly fitted into the inner circumferential annular groove 42 by the conical surface 32, and the squeegee 30 is moved inward of the inner circumferential annular groove 42. The squeegee 30 is contracted and deformed in the radial direction by the groove 34. The clearance between the spiral tooth portion 31 and the spiral groove 21 gradually increases from the inside to the outside. However, when the squeegee 30 is deformed in the radial direction, the gap between each spiral cutting tooth portion 31 and the spiral groove 21 becomes constant (that is, the deformation amount in the radial direction of the spiral cutting tooth portion 31 increases as it goes outward). . Therefore, the user can reduce the gap of the squeegee 30 as necessary, and the squeegee 30 is tightened when the fixing screw 43 screwed into the positioning hole 41 of the nut 40 is screwed in the radial direction.

  In order to increase the squeegee clearance, first, the fixing screw 43 is loosened (the squeegee 30 is not tightened), and the squeegee 30 according to the present invention is rotated in the reverse direction with respect to the nut 40. Then, the squeegee 30 gradually escapes from the inner peripheral surface annular groove 42 by the conical surface 32, and the squeegee 30 has a radius due to the cut groove 34 as the squeegee 30 moves to the outside of the inner peripheral surface annular groove 42. It expands and deforms in the direction, and the gap between the spiral toothed portion 31 and the spiral groove 21 is enlarged. Therefore, the user can enlarge the gap of the squeegee 30 as necessary. Furthermore, when the fixing screw 43 screwed into the positioning hole 41 of the nut 40 is screwed in the radial direction, the squeegee 30 is tightened.

  Further, a cut groove 34 penetrating the shaving tooth portion 31 is opened on the conical surface 32 of the squeegee 30, and the cut groove 34 is opened obliquely along the direction of the spiral groove 21 of the ball screw 20. Therefore, the squeegee 30 according to the present invention discharges the foreign matter along the cut groove 34 formed obliquely when the foreign matter is scraped by the spiral cutting tooth portion 31 (the foreign matter can be discharged to the outside). Therefore, the inclination angle can be appropriately designed according to the rotation direction). Therefore, according to the squeegee 30 according to the present invention, foreign matters are not excessively accumulated.

  In particular, a guide conical surface 33 is provided at one end of the conical surface 32 of the squeegee 30 according to the present invention, and the inner diameter of the inner circumferential surface annular groove 42 of the nut 40 is the maximum outer diameter of the squeegee 30. It is designed on condition that it is smaller than. Therefore, the guide cone surface 33 allows the worker of the assembling work to quickly attach the squeegee 30 to the inner peripheral surface annular groove 42 of the nut 40. Therefore, the assembling work of the squeegee 30 is facilitated.

Finally, as shown in FIGS. 8 to 10, the inner circumferential surface annular groove 42 of the nut 40 according to the present invention may have a cylindrical shape shown in FIG. 8, or a conical shape and a cylindrical shape shown in FIG. 9. It may be a combination, or may be a combination of two conical shapes shown in FIG. In these forms, the gap can be adjusted in the same manner as in the squeegee. Therefore, the inner peripheral surface annular groove 42 of the nut 40 according to the present invention can adjust the gap even if the above-mentioned form is appropriately selected and adopted as necessary.

It is sectional drawing of the prior art example 1. FIG. It is sectional drawing of the prior art example 2. FIG. It is sectional drawing of the prior art example 3. FIG. 1 is a perspective view of a squeegee according to the present invention. 1 is a side view of a squeegee according to the present invention. It is sectional drawing which shows the state in which the squeegee which concerns on this invention was assembled | attached. It is sectional drawing which shows the union state of this invention. It is sectional drawing which shows Example 1 of the internal peripheral surface annular groove of the nut which concerns on this invention. It is sectional drawing which shows Example 2 of the internal peripheral surface annular groove of the nut which concerns on this invention. It is sectional drawing which shows Example 3 of the internal peripheral surface annular groove of the nut which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Screw shaft 101 Spiral groove 111 Squeegee 111 Convex edge 12 Nut 121 Positioning screw element 13 Squeegee 131 Convex edge 132 Cut 14 Annular spring 15 Nut 16 C-type engagement ring 17 Annular brush 18 Screw shaft 20 Ball screw 21 Spiral groove 30 Squeegee 31 Shaving tooth portion 32 Conical surface 34 Groove 40 Nuts 41 Positioning hole 42 Inner peripheral surface annular groove 43 Fixing screw

Claims (4)

In a squeegee that is assembled between a nut and a screw shaft and is installed in an annular groove on the inner peripheral surface of the nut, the gap being adjustable.
The squeegee is an annular deflectable member whose maximum outer diameter is larger than the inner peripheral annular groove of the nut,
The outer peripheral surface is provided with a conical surface inclined to the inner peripheral surface annular groove of the nut,
The conical surface is provided with a kerf that penetrates the shaving portion to the back side,
On the back side of the squeegee, there is provided a helical tooth portion that meshes with the helical groove of the ball screw,
The gap between the helical tooth portion and the helical groove gradually increases from the inside of the nut of the squeegee to the outside of the nut of the squeegee,
Before SL helical scraping teeth, the end located inside the nut of the squeegee, helically extending to an end located outside of the nut of the squeegee, the width inside the nut of the squeegee The end portion located in the squeegee is wider than the end portion located outside the nut, and is formed so as to gradually decrease from the inside to the outside .
Squeegee with adjustable gap. 2. The squeegee with adjustable gap according to claim 1, wherein a guide conical surface is provided at one end of the conical surface of the squeegee, and the guide conical surface meshes with a spiral groove of the nut. The shape of the annular groove on the inner peripheral surface of the nut is any one of a cylindrical shape , a combination of a cylindrical shape and a conical shape , or a combination of two conical shapes, according to claim 1 or 2. Squeegee with adjustable gap. The squeegee with adjustable gap according to any one of claims 1 to 3, wherein the cut groove is formed obliquely in a direction in which the spiral groove of the ball screw is formed.

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