JPH05322005A - Idler pulley - Google Patents

Abstract

(57) [Summary] [Purpose] A sealing material is placed on the inner ring to securely prevent dust from entering the bearing. An outer ring portion 2 that contacts the belt, an inner ring portion 3 that is concentrically located inside the outer ring portion 2,
An idler pulley that includes a plurality of connecting members 4 that connect the outer ring portion 2 and the inner ring portion 3 and is rotatably supported by a support body 5 via a bearing 9 that contacts the inner peripheral surface of the inner ring portion 3. 1, the flexible sealing material 13 is provided on the outer surface of the inner ring portion 3 so as to come into contact with the plate material 10 and the overhanging portion 14 on the support body 5 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an idler pulley idlely supported by a support, and more particularly to a countermeasure for dust on a bearing.

[0002]

2. Description of the Related Art As shown in FIG. 3, an idler pulley a used for an automatic tensioner or the like generally has a plurality of connecting members d, d, ... Connecting an outer ring portion b and an inner ring portion c.
And is rotatably supported by a support body f via a bearing e that is in contact with the inner peripheral surface of the inner ring portion c. In such an idler pulley a, the bearing e is exposed from the gap between the inner ring portion c and the support body f, and dust enters the bearing e and causes abnormal noise and poor rotation. The plate material g is attached to the support body f with bolts h so that the bearing material e is covered with the plate material g.

[0003]

However, even if the bearing e is covered with the plate material g as described above, it is not possible to bring the plate material g into direct contact with the inner ring portion c in consideration of the rotation resistance of the idler pulley a. In addition, since there is play in the bearing e, a gap is inevitably formed between the inner ring portion c and the plate material g and the support body f, and dust enters through this gap, causing abnormal noise and poor rotation. ..

The present invention has been made in view of the above points, and an object thereof is to prevent dust from entering a bearing reliably by disposing a sealing material on the inner ring portion. And there is.

[0005]

In order to achieve the above-mentioned object, a solution means of the present invention according to claim 1 is an outer ring portion which comes into contact with a belt, and is located concentrically inside the outer ring portion. An idler that includes an inner ring portion and a plurality of connecting members that connect the outer ring portion and the inner ring portion, and is rotatably supported by a support through a bearing that contacts the inner peripheral surface of the inner ring portion. In the pulley, a flexible sealing material is provided on the outer surface of the inner ring portion so as to contact the support body side.

[0006] The solution means of the present invention according to claim 2 is that in the above-mentioned case, the flexible sealing material is applied or impregnated with oil.

[0007]

With the above construction, in the present invention according to claim 1, when the idler pulley is rotated, the flexible seal material provided on the outer surface of the inner ring portion is slidably contacted with the support body side. The flexible sealing material seals the gap between the support and the support side, dust is blocked by the flexible sealing material and does not enter the bearing, and abnormal noise and poor rotation are eliminated. Further, since the flexible sealing material only makes sliding contact with the support side, the sliding contact resistance is small and the rotation resistance of the idler pulley does not become so large. Further, even if the idler pulley is tilted, it does not come into direct contact with the support body side due to the interposition of the flexible sealing material, and abnormal noise and poor rotation are effectively eliminated.

According to the second aspect of the present invention, the oil which is applied or impregnated on the flexible sealing material enhances the dust trapping ability and enhances the dust intrusion prevention effect.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an idler pulley 1 according to an embodiment of the present invention. The idler pulley 1 is a belt (not shown)
And an inner ring portion 3 concentrically located inside the outer ring portion 2. The outer ring portion 2 and the inner ring portion 3 are connected to each other by a plurality of connecting members 4. , 4, ... Are linked together.

A support body 5 is inserted inside the inner ring portion 3, and a large number of balls 6, 6, ... Are provided between the support body 5 and the inner ring portion 3 with the outer race 7 and the inner race. A bearing 9 is sandwiched between the race 8 and the race 8.

Further, a disk-shaped plate member 10 is pushed from the side by a head 11b by screwing a shaft portion 11a of a bolt 11 into a screw hole 12 of the support body 5 at the tip of the support body 5. The inner race 8 of the bearing 9 is attached from the side by the plate member 10 so that the bearing 9 supports the support body 5.
I try not to leave. As a result, the idler pulley 1 is rotatably supported by the support 5 via the bearing 9 that contacts the inner peripheral surface of the inner ring portion 3.

The outer peripheral portion of the plate member 10 is curved outward in a C-shaped cross section so that the outer peripheral end faces the outer peripheral surface of the inner ring portion 3 so as to cover the bearing 9, and the outer peripheral end of the plate member 10 is covered. A gap having a predetermined distance is formed between the outer peripheral surface of the inner ring portion 3 and the inner ring portion 3.

Further, as a feature of the present invention, brush-like flexible sealing materials 13, 13 made of synthetic resin or the like are provided on both outer surfaces of the inner ring portion 3 on the support 5 side, that is, the outer periphery of the plate material 10. It is attached in a ring shape so as to come into contact with the inner surface of the end portion and the projecting portion 14 at the base end of the support body 5, respectively. Oil (not shown) is applied or impregnated on each of the flexible sealing members 13.

Therefore, since the both flexible seal members 13, 13 are brought into sliding contact with the plate member 10 and the overhanging portion 14 by the rotation of the idler pulley 1, the inner ring portion 3 and the plate member 10 are in contact with each other.
And between the flexible sealing material 13 and the overhanging portion 14,
13 can be completely sealed, dust can be reliably prevented from entering the bearing 9, and abnormal noise and defective rotation can be eliminated.

Further, since the sealing material 13 that is in sliding contact with the plate material 10 is flexible, the sliding contact resistance is small and it is possible to prevent the rotation of the idler pulley 1 from being hindered.

Further, even if the idler pulley 1 is tilted, the flexible seal member 1 is prevented from directly contacting the plate member 10 and the overhanging portion 14.
It is possible to prevent the noises and the rotation defects, and it is possible to effectively eliminate the abnormal noise and the defective rotation.

Further, the oil which is applied or impregnated on the flexible sealing materials 13 and 13 can enhance the dust trapping property and enhance the dust intrusion prevention effect.

Furthermore, there is an advantage that the grease leaked from the bearing 9 can be prevented from scattering to the outside by the flexible sealing materials 13, 13.

In the above embodiment, the flexible sealing material 1 is used.
Although a brush-like material is used as 3, a similar effect can be obtained even if a felt material or the like is attached to the outer surface of the inner ring portion 3.

[0021]

As described above, according to the present invention of claim 1, in an idler pulley rotatably supported by a support through a bearing, the idler pulley is flexible on the outer side surface of its inner ring portion. Since the sealing material is provided so as to be in contact with the side of the support, the intrusion of dust into the bearing can be reliably prevented by the flexible sealing material, and abnormal noise and rotation failure can be eliminated. Further, the sliding contact resistance of the flexible sealing material to the support side is small, and it is possible to prevent the rotation resistance of the idler pulley from increasing. Further, the flexible sealing material can prevent direct contact with the support side due to the inclination of the idler pulley, and it is possible to effectively eliminate abnormal noise and rotation failure.

According to the second aspect of the present invention, since the flexible sealing material is coated or impregnated with oil, it is possible to enhance the dust trapping ability by the oil and enhance the dust intrusion prevention effect.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an idler pulley.

FIG. 2 is an enlarged vertical sectional view showing a flexible sealing material portion of an idler pulley.

FIG. 3 is a view corresponding to FIG. 2 of a conventional example.

[Explanation of symbols]

 1 Idler Pulley 2 Outer Ring Part 3 Inner Ring Part 4 Connecting Member 5 Support 9 Bearing 13 Flexible Sealing Material

Claims (2)

[Claims] 1. An outer ring portion in contact with the belt, and an inner ring portion concentrically located inside the outer ring portion,
An idler pulley that is composed of a plurality of connecting members that connect the outer ring portion and the inner ring portion, and is rotatably supported by a support through a bearing that contacts the inner peripheral surface of the inner ring portion, An idler pulley, wherein a flexible sealing material is provided on the outer surface of the inner ring portion so as to contact the support body side. 2. The idler pulley according to claim 1, wherein the flexible sealing material is coated or impregnated with oil.