JP2829238B2 - Telescopic guide structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescopic guide structure.

[0002]

2. Description of the Related Art A linear moving ball bearing device disclosed in Japanese Patent Publication No. 60-25650 is known as a telescopic guide structure used for telescopic legs and the like of a drawing table.

[0003]

In this apparatus, four round bar rails in the longitudinal direction are respectively attached to the inner surface of an outer cylinder and the outer surface of an inner cylinder inserted into the outer cylinder. The outer cylinder and the inner cylinder are extended and contracted by rolling the ball between the four rail shafts. In addition, the channel material was welded and bent into a U-shape to mount the four rail shafts. Therefore, there is a problem that many components are required for the expansion and contraction guide, and the production is troublesome.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a telescopic guide structure which requires a small number of components and has a small play of a ball, and can perform a smooth telescopic guide.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides an outer cylinder and a plurality of inner cylinders inserted into the outer cylinder which are rotatably held by a retainer. Via a ball, is a telescopic guide structure for telescopic guidance, wherein the outer cylindrical body is formed of a bent plate material and the inner cylindrical body is formed integrally with the bent plate material in a continuous tubular shape, and By bending the bent plate material itself forming the outer cylinder and the inner cylinder, the outer V-groove and the inner V-groove in the longitudinal direction which also serve as ribs are aligned with the inner circumferential surface of the outer cylinder which faces each other and the inner V-groove. The ball is formed on the outer peripheral surface of the cylindrical body, and the ball is rotatably held between the outer V-groove and the inner V-groove.

[0006]

When the outer cylinder and the inner cylinder are relatively moved in the longitudinal direction, the ball rolls in the outer V-groove and the inner V-groove, and the outer cylinder and the inner cylinder are guided to expand and contract. At this time, since the outer V-groove and the inner V-groove come into contact with the ball from all sides, the backlash of the ball during rolling is regulated, and the outer cylinder and the inner cylinder slide and expand and contract smoothly.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing embodiments.

FIG. 1 and FIG. 2 show an embodiment of a telescopic guide structure according to the present invention.
And an inner cylinder 2 loosely inserted into the outer cylinder 1 in the longitudinal direction (axial direction) so as to be relatively movable in the longitudinal direction (axial direction). A ball 4 made of a plurality of steel balls or the like held rotatably by a retainer 3. For example, the outer cylinder 1 can be used as a movable side and the inner cylinder 2 can be used as a support and fixed side, and can be used as an extendable leg of a drafting table or an extendable leg of an overbed table.

More specifically, the outer cylinder 1 is formed of a bent plate material so that its cross section has a substantially square shape. In the illustrated example, the outer cylinder 1 has a main bent plate portion 5a having one side opening and a sub-folded plate portion 5b provided so as to cover one side opening of the main bent plate portion 5a from inside. And consisting of

The inner cylindrical body 2 is formed of a bent plate material and has a substantially rectangular cross section , and is integrally formed in a cylindrical shape with no break.

Further, longitudinally outer V-grooves 6 and inner V-grooves 7 are formed on the inner peripheral surface of the outer cylindrical body 1 and the outer peripheral surface of the inner cylindrical body 2 at predetermined intervals, respectively. Groove 6 and inner V groove 7
Are arranged so as to be able to roll freely.

At least one pair of the inner and outer V-grooves 7 and 6 are arranged so as to be substantially symmetrical with respect to a center line W which bisects the outer cylinder 1 or the inner cylinder 2 from the center in a cross section.

In the illustrated example, the outer V-groove 6 and the inner V-groove 7 are opposed in parallel to one side wall 1a of the outer cylinder 1 and one side wall 2a of the inner cylinder 2, and to face in parallel. Other side wall 1 of outer cylinder 1
b and the other side wall 2b of the inner cylindrical body 2 respectively.

The outer V-groove 6 and the inner V-groove 7 are formed by bending the bent plate material forming the outer cylinder 1 and the inner cylinder 2. For example, as shown in the figure, in the outer cylinder 1, a part of the one side wall 1a and a part of the other side wall 1b are bent outward in a V-shape, and in the inner cylinder 2, An outer V-groove 6 and an inner V-groove 7 are formed by bending a part of the one side wall 2a and a part of the other side wall 2b in a V-shape.

Since the outer V-groove 6 and the inner V-groove 7 have a simple V-shape, they can be easily formed integrally. In addition, the outer V groove 6 and the inner
The V-groove 7 is formed in the outer cylinder 1 and the inner cylinder 2 in the longitudinal direction.
It also serves as a rib to increase strength
You. As described above, the channel material and the rail shaft of the round bar which have been conventionally used for the expansion and contraction guide become unnecessary, the number of parts can be reduced, and the production becomes easy. Next, the retainer 3 is shaped like a strip, and a plurality of ball holding holes 8 are formed at appropriate intervals in the longitudinal direction.

While the ball 4 is rotatably held in the ball holding hole 8, the ball 4 is inserted between the outer V-groove 6 and the inner V-groove 7, and the retainer 3 is inserted into the outer cylinder 1. Between the peripheral surface and the outer peripheral surface of the inner cylindrical body 2 (in the illustrated example, one side wall 1a, 2
a) and between the other side walls 1b and 2b). In order to prevent the retainer 3 and the ball 4 from coming out when the outer cylinder 1 and the inner cylinder 2 are expanded and contracted, a stopper is appropriately provided on the outer cylinder 1 or the inner cylinder 2.

Thus, the telescopic guide structure is formed. As shown in FIGS. 2 and 3, the outer cylinder 1 and the inner cylinder 2 are relatively moved in the longitudinal direction, so that the ball 4 rolls in the outer V-groove 6 and the inner V-groove 7. The outer cylindrical body 1 and the inner cylindrical body 2 are guided to expand and contract.

In the present invention, as shown in FIGS. 1 and 4, the cross-sectional shape of the rolling surface of the ball 4 is V-shaped,
The inclined surfaces 6a and 6b of the outer V groove 6 and the inclined surfaces 7 of the inner V groove 7
a, 7b come into contact with the ball 4 from all sides, and the inner and outer cylindrical bodies 2,
Since the backlash between the ball 4 and the inner and outer cylinders 2 and 1 in the direction orthogonal to the longitudinal direction of the first cylinder 1 (particularly in the direction of the center line W) can be regulated, the outer cylinder 1 and the inner cylinder 2 slide smoothly. To expand and contract.

By the way, although not shown, the inner and outer cylinders 2,
Assuming that the cross-sectional shape of the rolling surface of the ball 4 at 1 is arc-shaped, unless the rolling surface of each of the inner and outer cylinders 2 and 1 is machined with high precision in accordance with the ball radius (for example, one rolling surface) When the radius is larger than the ball radius, the rattling between the inner and outer cylinders 2 and 1 and the ball 4 in the direction of the center line W cannot be suppressed, but in the present invention, the outer V groove 6 and the inner V groove 7 are used. Even if the shapes (for example, the inclination angles α and β of the two 6 and 7) are slightly different from each other, the rattling with the ball 4 can be suppressed as described above, and the processing becomes easy.

The present invention is not limited to the above-described embodiment, and the design can be freely changed without departing from the gist of the present invention. For example, the outer cylinder 1 and the inner cylinder 2 have a substantially square cross section, but may have other polygonal shapes, elliptical shapes, circular shapes, or the like. When used for telescopic legs or the like of a drafting table, the outer cylinder 1 may be on the fixed support side, the inner cylinder 2 may be on the movable side, or both 1 and 2 may be on the movable side.

[0021]

Since the present invention is configured as described above, the following significant effects can be obtained.

According to the telescopic guide structure of the first aspect,
Since the number of components constituting the telescopic guide structure can be reduced, and the outer V-groove 6 and the inner V-groove 7 do not require high-precision processing, they can be easily manufactured. In addition, rattling between the outer V-groove 6 and the inner V-groove 7 and the ball 4 is small, and the outer cylinder 1 and the inner cylinder 2 can be smoothly expanded and contracted.

Further, the inner V-groove 7 and the outer V-groove 6, since the form in the folded sheet itself form the outer cylinder 1 and the inner cylinder 2, Hakare lighter, and the outer V-groove 6 And the portion forming the inner V-groove 7 can also be used as a rib, and the strength of the outer cylinder 1 and the inner cylinder 2 can be increased.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view.

FIG. 3 is a longitudinal sectional view.

FIG. 4 is an enlarged cross-sectional view of a main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 Inner cylinder 3 Retainer 4 Ball 6 Outer V groove 7 Inner V groove

Continuation of the front page (56) References JP-A-51-120861 (JP, A) JP-A-57-49410 (JP, A) JP-A-2-26189 (JP, A) Real opening , U) JP-B 63-6206 (JP, B2) JP-B 60-34187 (JP, B2) JP-B 60-25650 (JP, B2) JP-B 54-18435 (JP, Y2) (58) Field surveyed (Int.Cl. ⁶ , DB name) F16D 29/00-29/06 A47B 88/08 A47B 9/20

Claims (1)

(57) [Claims] 1. An expansion and contraction guide for guiding an outer cylinder 1 and an inner cylinder 2 inserted into the outer cylinder 1 via a plurality of balls 4 rotatably held by a retainer 3. A structural body, wherein the outer cylindrical body 1 is formed of a bent plate material and the inner cylindrical body 2 is integrally formed of a bent plate material into a continuous cylindrical shape;
In addition, the bent plate material itself forming the outer cylinder 1 and the inner cylinder 2 is bent, and the outer V-groove 6 and the inner V-groove 7 in the longitudinal direction which also serve as ribs are connected to the outer cylinder 1 facing each other. Are formed on the inner peripheral surface of the inner cylindrical body 2 and the outer peripheral surface of the inner cylindrical body 2, respectively.
A telescopic guide structure wherein the ball 4 is rotatably held between the groove 7.