JP2008157370A - Follower bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a follower bearing effectively preventing the leakage of grease to the outside of the bearing without increasing torque loss. <P>SOLUTION: The follower bearing comprises an inner ring 12, an outer ring 13, a plurality of rollers arranged along the raceway surfaces of the inner ring 12 and the outer ring 13, and a seal 16 as a sealing member having a fixed portion 16a fixed to the outer ring 13, a contact lip portion 16b abutting on the inner ring 12, and a non-contact lip portion 16c arranged axially inside of the contact lip portion 16b at a predetermined clearance from the inner ring 12 for sealing the clearance between the inner ring 12 and the outer ring 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a follower bearing, for example, a follower bearing for a tenter clip in a film manufacturing process.

  A conventional roller follower 101 will be described with reference to FIGS. 4 and 5. 4 is a cross-sectional view of the roller follower 101, and FIG. 2 is a view showing a hermetic seal 107 employed in the roller follower 101.

  Referring to FIG. 4, roller follower 101 includes an inner ring 102, an outer ring 103, a plurality of rollers 104 disposed between inner ring 102 and outer ring 103, and a cage 105 that holds a gap between adjacent rollers 104. A pair of side plates 106a and 106b that are fitted to both axial ends of the inner ring 102 and rotate integrally with the inner ring 102, and a sealing seal 107 that is disposed between the outer ring 103 and the pair of side plates 106a and 106b, respectively. The bearing is filled with grease that lubricates the rolling surface of the roller 104.

  Next, referring to FIG. 5, the hermetic seal 107 includes a fixing portion 107 a that is fixed to the outer ring 103 and a contact lip portion 107 b that contacts the side plates 106 a and 106 b. The contact lip 107b has a gradually decreasing cross-sectional thickness from the base toward the tip, and the vicinity of the tip is in sliding contact with the outer diameter surfaces of the side plates 106a and 106b.

  The sealing seal 107 having the above configuration is provided mainly for preventing dust from entering the bearing. When the roller follower 101 is used in a high rotation and high load environment, the grease seal outside the bearing is used. May not be completely prevented. Therefore, it could not be used as a bearing for an environment where grease leakage is not allowed, for example, a tenter clip guide of a film stretching machine.

Therefore, a rolling bearing having a hermetic seal that prevents grease from leaking outside the bearing is described in, for example, Japanese Utility Model Publication No. 47-6802 (Patent Document 1). The sealing member described in the publication has two contact lip portions that are in sliding contact with the outer diameter surface of the inner ring. Thus, it is described that it can completely resist the flow pressure due to the stirring resistance of the grease and the pressure of the outside air, and exhibits the sealing effect completely.
Japanese Utility Model Publication No. 47-6802

  The hermetic seal described in the above publication has a problem that torque loss due to contact with the inner ring is larger than that of a single contact lip portion. On the other hand, in the roller follower 101 as shown in FIG. 4, measures for preventing leakage of grease are taken. Specifically, a method of significantly reducing the amount of grease filled in the bearing or increasing the contact pressure between the inner ring 102 and the contact lip 107b can be used.

  However, if the amount of grease is reduced, the lubrication performance, which is the original purpose, is lowered, and there is a concern that the bearing life may be reduced. Further, when the contact pressure between the inner ring 102 and the contact lip 107b is increased, the torque loss increases.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a follower bearing that effectively prevents leakage of grease to the outside of the bearing without increasing torque loss.

  A follower bearing according to the present invention is fixed to an inner ring having a raceway surface on an outer diameter surface, an outer ring having a raceway surface on an inner diameter surface, a plurality of rollers disposed along the raceway surfaces of the inner ring and the outer ring, and the outer ring. A fixed lip portion, a contact lip portion that contacts the inner ring, and a non-contact lip portion arranged with a predetermined gap between the inner ring and the inner ring on the inner side in the axial direction from the contact lip portion, and seals the gap between the inner ring and the outer ring And a sealing member.

In the sealing member configured as described above, the non-contact lip portion reduces the amount of grease reaching the position of the contact lip portion due to the labyrinth effect with the inner ring. And the contact lip is
Prevents grease from leaking outside the bearing and dust from entering the bearing. Thereby, sealing performance improves. Further, by making one of the two lip portions non-contact, an increase in torque loss due to contact with the inner ring can be suppressed.

  Preferably, the cross-sectional thickness of the contact lip portion increases from the root toward the tip. Thereby, the elastic deformability of a contact lip part improves. As a result, it is possible to maintain the sealing performance corresponding to the change in the radial clearance between the inner ring and the outer ring, and to suppress an increase in torque loss.

  Preferably, the contact lip has an acute corner that contacts the inner ring. As a result, the contact area between the contact lip portion and the inner ring is reduced. As a result, an increase in torque loss can be suppressed more effectively.

  Preferably, the sealing member is made of a resin material. The sealing member having the above-described configuration is desirably manufactured from a resin material having a high elastic deformability from the viewpoint of suppressing an increase in torque loss due to contact with the inner ring. Examples of the resin material include nitrile rubber, fluorine rubber, and silicone rubber.

  According to the present invention, by using a sealing member having a contact lip portion and a non-contact lip portion, a follower bearing that effectively prevents leakage of grease to the outside of the bearing without increasing torque loss is obtained. Can do.

  With reference to FIG. 1 and FIG. 2, the roller follower 11 as a follower bearing which concerns on one Embodiment of this invention is demonstrated. 1 is a cross-sectional view of the roller follower 11, and FIG. 2 is an enlarged cross-sectional view of the periphery of the hermetic seal 16.

  First, referring to FIG. 1, the roller follower 11 is disposed along the inner race 12 having a raceway surface on the outer diameter surface, the outer ring 13 having the raceway surface on the inner diameter surface, and the raceway surfaces of the inner ring 12 and the outer ring 13. A plurality of rollers 14, a retainer 15 that holds an interval between adjacent rollers 14, and a sealing seal 16 as a sealing member that seals a gap between the inner ring 12 and the outer ring 13. It is filled with grease that lubricates the rolling surface.

  The inner ring 12 includes a cylindrical inner ring member 12a and a pair of side plates 12b. The inner ring member 12a has an inner diameter surface that fits on the rotation shaft and an outer diameter surface that has a raceway surface. The pair of side plates 12b are ring members that are fitted to both ends of the inner ring member 12a in the axial direction and rotate integrally, and are separate from the inner ring member 12a from the viewpoint of assembly of the roller follower 11.

  Next, referring to FIG. 2, the hermetic seal 16 is an annular member formed by injection molding of a resin material. As the resin material, for example, nitrile rubber, fluorine rubber, silicone rubber, or the like can be used.

  The hermetic seal 16 is a ring-shaped member, and has a fixed portion 16 a fixed to the outer ring 13 at an outer diameter portion thereof, a contact lip portion 16 b and a non-contact lip portion 16 c at an inner diameter portion, and a seal seal 16. And a metal core 16d that holds the shape. The fixing portion 16a is fitted into the fixing groove 13a of the outer ring 13, and the two lip portions 16b and 16c are arranged so as to face the outer diameter surface of the side plate 12b.

  The contact lip portion 16b has an inversely tapered shape whose cross-sectional thickness increases from the base toward the tip, and the tip portion (the innermost diameter portion) is provided with an acute angle corner portion 16e that contacts the outer diameter surface of the side plate 12b. It has been. On the other hand, the non-contact lip portion 16c branches off from the root portion of the contact lip portion 16b, and extends downward at a predetermined angle. A predetermined gap is provided between the tip of the non-contact lip portion 16c and the outer diameter surface of the side plate 12b. The non-contact lip portion 16c of the hermetic seal 16 is disposed on the inner side in the axial direction of the inner ring 12 than the contact lip portion 16b.

  The hermetic seal 16 configured as described above produces a labyrinth effect between the non-contact lip portion 16c and the outer diameter surface of the side plate 12b. Further, by inclining the non-contact lip portion 16c, the grease is guided to the inner wall surface in the axial direction of the non-contact lip portion 16c and moves outward in the radial direction. As a result, it is possible to prevent the grease inside the bearing from moving outward in the axial direction to some extent. On the other hand, the contact lip portion 16c contacts the outer diameter surface of the side plate 12b to prevent dust from entering the bearing. Further, since the amount of grease reaching the position of the contact lip portion 16c is reduced by the labyrinth effect of the non-contact lip portion 16c, leakage of grease to the outside of the bearing can be effectively prevented.

  Since no contact resistance occurs between the non-contact lip portion 16c and the side plate 12b, there is no increase in torque loss due to the provision of the non-contact lip portion 16c. Moreover, the contact area can be reduced by making the part which contacts the side plate 12b of the contact lip | rip part 16b into the acute angle | corner corner | angular part 16e. As a result, an increase in torque loss can be suppressed.

  Furthermore, the elastic deformability is improved by making the contact lip portion 16b into an inversely tapered shape. As a result, it is possible to maintain the sealing performance in response to the change in the radial gap between the inner ring 12 and the outer ring 13 and to suppress an increase in torque loss.

  Next, a test for confirming the effect of the present invention will be described. In the test, a roller follower (invention product) according to an embodiment of the present invention as shown in FIG. 1 and a conventional roller follower (conventional product) as shown in FIG. (Tangential force) and the amount of grease leaked to the outside of the bearing. Specifically, the test was conducted at room temperature for 2 hours at a grease filling amount of 100% with respect to the bearing internal space, a radial load applied to the bearing of 170 N and a rotational speed of 700 rpm. The results are shown in FIG.

  Referring to FIG. 3, about 40% of the grease leaked to the outside of the bearing in the conventional product, but no grease leakage was confirmed in the invention product. Thereby, it was confirmed that the leakage of grease can be effectively prevented by employing the hermetic seal 16 as shown in FIG. Moreover, there was almost no difference in rotational torque between the invention product and the conventional product. Accordingly, it was confirmed that the increase in torque loss can be suppressed by adopting the hermetic seal 16 shown in FIG.

  Moreover, although the sealing seal | sticker 16 in said embodiment showed the example which has the non-contact lip | rip part 16c one by one, you may provide the some non-contact lip | rip part 16c, without restricting to this. Thereby, the sealing performance of the hermetic seal 16 is further improved. On the other hand, torque loss does not increase even if a plurality of non-contact lip portions 16c are received.

  Moreover, although the sealing seal 16 in the above embodiment has shown an example in which the non-contact lip portion 16c is provided only on the inner side of the contact lip portion 16b, in addition to this, in addition to this, the outer side of the contact lip portion 16b (“the inner ring 12 It may be provided on the “axially outer side”. This is particularly effective when used outdoors where there is a high risk of dust contamination.

  Further, the roller follower 11 in the above embodiment can be used for any application, but is particularly suitable for use in an environment where a reduction in torque loss is required or an environment where grease leakage is not allowed. For example, a tenter clip bearing or the like in the film manufacturing process may be used.

  Furthermore, in the above embodiment, the example of the roller follower 11 is shown as the follower bearing according to the present invention, but the present invention can also be applied to a cam follower. That is, the “follower bearing” in the present specification should be understood as a concept including not only a roller follower but also a cam follower.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The present invention is advantageously used for a follower bearing.

It is sectional drawing of the roller follower which concerns on one Embodiment of this invention. FIG. 2 is an enlarged sectional view around a sealing member of the roller follower shown in FIG. 1. It is a figure which shows the result of the test which confirms the effect of this invention. It is a figure which shows the conventional roller follower. It is an enlarged view of the sealing member of the roller follower shown in FIG.

Explanation of symbols

  11, 101 Roller follower, 12, 102 Inner ring, 12a Inner ring member, 12b, 106a, 106b Side plate, 13, 103 Outer ring, 13a Fixing groove, 14, 104 Roller, 15, 105 Cage, 16, 107 Seal seal, 16a, 107a fixed part, 16b, 107b contact lip part, 16c non-contact lip part, 16d cored bar, 16e corner part.

Claims (4)

An inner ring having a raceway surface on the outer diameter surface;
An outer ring having a raceway surface on the inner diameter surface;
A plurality of rollers disposed along the raceways of the inner ring and the outer ring;
A fixed portion fixed to the outer ring; a contact lip portion that contacts the inner ring; and a non-contact lip portion that is disposed with a predetermined clearance from the inner ring on an inner side in the axial direction from the contact lip portion. And a sealing member that seals a gap between the outer rings.   The follower bearing according to claim 1, wherein a cross-sectional thickness of the contact lip portion increases from a root toward a tip.   The follower bearing according to claim 1, wherein the contact lip portion has an acute corner portion that contacts the inner ring. The follower bearing according to claim 1, wherein the sealing member is formed of a resin material.

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