JPS5835882Y2 - belt tensioner - Google Patents

Description

[Detailed description of the invention] This invention relates to a belt tensioner, and in particular uses a general rolling bearing in which rolling elements such as balls and rollers are arranged between an outer ring and an inner ring as the rotating element of the tensioner, and this makes it possible to rotate the belt tensioner. Our goal is to provide a belt tensioner with high precision and long service life.

Generally, when maintaining the tension of a belt, a so-called tensioner is used, and the belt is compressed by the tensioner to remove slack.

This tensioner is also incorporated into the belt drive mechanism of an internal combustion engine.

When a belt drive mechanism is used in such internal combustion engines, particularly as a means of driving a power distribution unit, belt elongation has a considerable adverse effect on the ignition timing.

Therefore, in this case, it is particularly important that the tensioner itself is robust and that it always maintains high precision as a rotating body.

This invention was developed to satisfy the above-mentioned requirements, and will be explained below with reference to a typical embodiment shown in FIGS. 1 and 2. In embodiment 1, a belt tensioner, 2 is a ball bearing as a rotating element, 3 is an outer ring in contact with a belt (not shown), 4 is an inner ring on the fixed side, 5 is a holding plate for fixing, 6 is a bracket for position adjustment, 1 is for mounting the bracket is a member, and 8 is a fixing bolt.

The ball bearing 2 is sealed by a seal body S fixed to an outer ring 3, and the outer ring 3 is wider than the inner ring 4 so that a presser plate 5, which will be described later, does not protrude from the end surface of the bearing 2.

In particular, in this example, a single-row ball bearing is shown, but the same method can be applied to a double-row ball bearing.

The holding plate 5 includes a fitting portion 51 that is press-fitted and fixed to the inner peripheral surface of one end of the inner ring 4, a positioning flange (periphery) 52 that has a larger diameter than this and contacts the end surface of the inner ring, and a center position. and a bottom wall 53 having a long hole 54 for adjusting the position of the tensioner white body.

The holding plate 5 in this embodiment has its original form cast,
Although this was formed by performing the necessary finishing machining, it may also be machined from a solid body, or it may be press-formed from a steel plate for the casing.

Alternatively, the mesh part and the flange part may be continuous in the circumferential direction or may be discontinuous depending on the forming means.

The bracket 6 has a fitting portion 61 that is press-fitted to the inner circumferential surface of the other end of the inner ring 4, and a shoulder portion 62 that has a larger diameter than the fitting portion 61 and is positioned in contact with the end surface of the inner ring in the axial direction. An extension, for example a cylindrical part 63, and a subsequent attachment surface 64 are formed.

The mounting has ears 641 and 642 that protrude in the radial direction at two places on the circumference of the surface 640, and one ear 64
1 has a bolt insertion hole 643 that serves as a fulcrum for adjusting the tensioner's position, and the other ear 642 has a hole 644 that engages a coil spring that pulls the tensioner in one direction.

The ball bearing 2, the presser plate 5, and the bracket 6 as rotating elements thus formed are assembled in the relationship shown in FIG. 2 to form the belt tensioner of this invention.

As mentioned above, the belt tensioner of this invention uses general rolling bearings for the rotating elements, so it not only has excellent rotational performance and long life, but also has separate parts. Since the presser plate and bracket are integrally held against the inner ring, the parts of the tensioner itself can be handled as a unit without being separated from each other, and there is also a fitting part for attaching the inner ring to the bracket. Therefore, it is easy to fit the inner ring, and it is also easy to align the elongated holes in the holding plate.
It is advantageous in terms of ease of handling and cost reduction.

In addition, if the inner ring of the bearing and the retaining plate or bracket are held in such a way that they do not separate, the retaining plate or bracket can be rotated with a small amount of force relative to the inner ring, so the tensioner can be attached to the mounting member using bolts. When installing, there is almost no need to consider the alignment accuracy of the elongated holes.

Furthermore, since the holding plate and the bracket are formed with a flange portion or a shoulder portion of an arbitrary shape that serves as a stopper for positioning the inner ring, when assembling it to the inner ring, simply push it in from the end face side of the inner ring. As a result of being able to assemble easily and reliably, it is possible to improve accuracy and reduce manufacturing costs.

As a matter of course, the embodiment is merely one example of the invention, and the invention may be implemented with appropriate modifications within the scope of the claims.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along the line AA in FIG. 2 showing an embodiment of the belt tensioner of this invention, and FIG. 2 is a front view of the tensioner shown in FIG. 1. In the examples, 1 is a belt tensioner, 2 is a ball bearing, 3 is an outer ring, 4 is an inner ring, 5 is a holding plate, 6 is a bracket, 7 is a mounting member, and 8 is a bolt.

Claims (2)

[Scope of utility model registration request] (1) In a belt tensioner that has rolling elements between an outer ring and an inner ring so that the outer ring can rotate in contact with the belt, one end face of the inner ring has a It is equipped with a holding plate that has a fitting part fixed to the inner circumferential surface, a positioning flange with a larger diameter than this and in contact with the end face of the inner ring, and a bottom wall that is long enough to adjust the position of the tensioner itself. , a fitting portion fixed to the inner circumferential surface of the end side of the inner ring, an axially extending cylindrical portion having a larger diameter than the fitting portion and a shoulder portion for positioning that contacts the end surface of the inner ring, and a subsequent mounting portion. Features a bracket with a Tachelt tensioner. (2) The belt tensioner according to claim 1, wherein the outer ring width is larger than the inner ring width.