JPH0223854Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a linear carriage that is incorporated into a linear sliding portion of an optical device or the like.

[Conventional technology]

As a guide device for moving a slidable member while keeping it in a horizontal state, two guide shafts are installed in parallel, and the outer circumferential surface of the guide shaft is inserted into the shaft insertion hole of the housing passed between the guide shafts. There is one in which a linear ball bearing is attached as a raceway surface, and the slidable member is supported by the housing.

However, in order to move the housing smoothly, the guide device described above needs to support two axes in parallel with high precision, and there is a problem in that it takes a lot of effort to assemble. Furthermore, since the two shafts are installed in parallel, the guide device becomes large, making it unsuitable for machines and equipment that are intended to be downsized.

U.S. Pat. No. 3,186,775 discloses a linear carriage in which a housing is movably supported along a single guide shaft. The linear carriage is shown in FIGS. 4 and 5 of the accompanying drawings. As shown, housing 2
0 is provided with a rod insertion hole 21, and a flat guide surface 23 in the axial direction is formed on the outer periphery of the rod 22 inserted into the rod insertion hole 21. A pair of linear ball bearings 24 are attached to both ends of the rod insertion hole 21, with the outer peripheral surface of the rod 22 serving as a ball rolling surface. Further, a needle bearing 25 whose rolling surface is the guide surface 23 of the rod 22 is rotatably attached to the housing 20.

In the linear carriage constructed as described above, the housing 20 is supported movably in the axial direction by the linear ball bearing 24, and the housing 20 rotates about the rod 22 by engagement between the needle bearing 25 and the guide surface 23. It prevents you from doing so.

By the way, in the above linear carriage,
If there is looseness between the needle bearing 25 and the guide surface 23, the housing 20 will run out around the rod 22, so it is necessary to apply an appropriate preload between the needle bearing 25 and the guide surface 23. .

Therefore, in the linear carriage shown in FIGS. 4 and 5, the needle bearing 25 is supported by an eccentric pin 26, and the rotation of the eccentric pin 26 presses the needle bearing 25 against the guide surface 23.

[Problem that the invention attempts to solve]

However, when adjusting the preload by rotating the eccentric pin 26, the preload force changes slightly depending on the rotation angle of the eccentric pin 26, so it is extremely difficult to apply an appropriate preload, and it takes a lot of effort to adjust the preload. There is an inconvenience that it takes. Furthermore, there is a risk that the eccentric pin 26 may rotate due to vibrations transmitted to the housing, and there is a problem that the preload is likely to change.

In view of the above points, the technical problem of this invention is to improve the motion performance of the housing by applying a constant preload between the guide surface of the rod and the rotating body in contact with it.

[Means for solving problems]

In order to solve the above problems, this invention forms a rod insertion hole in the housing, forms a flat guide surface in the axial direction on the outer periphery of the rod inserted into the rod insertion hole, and rolls on this guide surface. A rotating body to be used as a surface is placed in the storage space provided in the housing, and the support pin of the rotating body is fitted into the pin insertion hole provided in the housing with a margin in the radial direction, and the support pin is inserted into the pin insertion hole. An elastic body is provided that applies pressure in the radial direction, and the elastic body presses the rotating body against the guide surface to apply an appropriate preload between the two.

〔Example〕

Embodiments of this invention will be described below with reference to FIGS. 1 to 3.

As shown in the figure, a rod insertion hole 2 is formed in the housing 1, passing through it from one end to the other end. Both ends of the rod insertion hole 2 are formed into large diameter holes 3, and linear ball bearings 4, 4 are attached to each of the large diameter holes 3.

A rod 5 is inserted into the inside of the linear ball bearing 4, and a flat guide surface 6 in the axial direction is formed on the outer periphery of the rod 5. This guide surface 6
may be formed over the entire length of the rod 5, or may be formed only at the center of the rod 5, taking into account the stroke of the housing 1, as shown.

The housing 1 has a storage space 7 that is open on the side and communicates with the center of the rod insertion hole 2, and inside the storage space 7 is a radial bearing whose rolling surface is the guide surface 6 of the rod 5. Rotating body 8 such as
is located. Both ends of a support pin 9 that supports the rotating body 8 are inserted into pin insertion holes 10 formed in the housing 1.

The inner diameter of the pin insertion hole 10 is larger than the outer diameter of the support pin 9, and a radial gap is provided between the pin insertion hole 10 and the support pin 9 to allow the support pin 9 to move in the radial direction. A fitting groove 11 is formed in the inner peripheral surface of the pin insertion hole 10, and the inner diameter of the O-ring 12 fitted in the fitting groove 11 is smaller than the outer diameter of the support pin 9. Also, the second
As shown in the figure, the dimension L between the axis A of the pin insertion hole 10 and the guide surface 6 of the rod 5 is smaller than the radius r of the rotating body 8. For this reason, the rotating body 8
When the outer periphery of the rotary body 8 is in contact with the guide surface 6 of the rod 5, the axis of the rotating body 8 is eccentric with respect to the axis of the pin insertion hole 10, and a part of the O-ring 12 is compressed due to the eccentricity. The rotating body 8 is pressed against the guide surface 6 by the restoring elasticity caused by the compression of the O-ring 12, and an appropriate preload is applied between the rotating body 8 and the guide surface 6.

This structure prevents the housing 1 from rotating around the rod 5, and allows the housing 1 to move smoothly in the axial direction of the rod 5 while maintaining a horizontal state.

In the case of the embodiment, the O-ring 12 is shown as an elastic member that applies preload between the rotating body 8 and the guide surface 6, but the elastic member is not limited to this, and may be, for example, a leaf spring or a bent plate. It is also possible to use a wave spring in which the spring is formed into an annular shape.

〔effect〕

As described above, this invention loosely fits the support pin of the rotating body into the pin insertion hole formed in the housing, attaches an elastic member inside the pin insertion hole, and attaches the rotating body to the flat guide surface of the rod. Since the housing is pressed, a constant preload can be applied between the rotating body and the guide surface, which can have a great effect on improving the motion performance of the housing.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional plan view showing an embodiment of the linear carriage according to this invention, and Fig. 2 is a -
3 is a partially cutaway perspective view of the same as above, FIG. 4 is a partially cutaway sectional view showing a conventional linear carriage, and FIG. 5 is a sectional view taken along the - line of FIG. 4. be. 1...Housing, 2...Rod insertion hole, 4...
... Linear ball bearing, 5 ... Rod, 6 ... Guide surface, 7 ... Storage space, 8 ... Rotating body, 9 ... Support pin, 10 ... Pin insertion hole, 12 ... O ring.

Claims (1)

[Scope of utility model registration request] A rod insertion hole is formed in the housing, and a flat guide surface in the axial direction is provided on the outer periphery of the rod inserted into the rod insertion hole. , place the rotating body with the guide surface as the rolling surface in the storage space provided in the housing, and fit the support pin of the rotating body into the pin insertion hole formed in the housing with a margin in the radial direction. A linear carriage, wherein an elastic body is provided inside the pin insertion hole to press the support pin in the radial direction and press the rotating body against the guide surface.