JPH018738Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement of a plastic bearing protection plate used in a sealed type bearing.

(Prior Art) In sealed type bearings, protective plates made of steel plates have been widely used. However, since the outer periphery of the protection plate is pushed into the locking groove on the outer ring side by the stamping process, in miniature bearings, etc., the stamping process may cause cracks in the outer ring end or distortion of the outer diameter, and may also occur over time. Due to this change, the elastic force of the bent portion weakens, causing the protection plate to rattle and generate noise.

On the other hand, various types of plastic protection plates have been developed to avoid the problems encountered with steel protection plates.

Fig. 5 shows an example (Utility Model Application Publication No. 49-43636), in which the sealing plate A is formed from a plastic plate of approximately uniform thickness, and the inner ring side has a protruding edge B, and A mounting portion C is formed on the outer ring side, the outer periphery of which is curved in an inverted U-shape. As shown in FIG. 6, the mounting portion C of the sealing plate A is inserted into the substantially rectangular groove D on the outer ring side by bending the mounting portion C and pressing it from the outside. Due to the elastic force, the mounting portion C is fitted into the groove D in a bent state.

However, since the plastic sealing plate A is configured to be fitted into the groove D by the elastic force of the mounting part C in a bent state, the molding accuracy of the mounting part C and the groove D If the machining accuracy is poor, it will be difficult to fix the sealing plate A perpendicularly to the inner and outer rings, and the projecting edge portion B will tilt inward or outward.

Also, when the sealing plate A thermally expands, the mounting part C becomes the sixth
Since the shape changes to that shown by the dotted line in the figure, it becomes extremely difficult to maintain the mounting position of the sealing plate A constant, and the protruding edge B tilts inward or outward.

Furthermore, when the shape of the mounting portion C becomes as shown by the dotted line in FIG. 6 due to thermal expansion, stress F due to the expansion is applied approximately perpendicularly to the outer ring. As a result, the end of the outer ring is forced wider in the direction of the arrow, causing distortion and deterioration of roundness.

(Problems to be Solved by the Invention) This invention solves the above-mentioned problems with conventional plastic protection plates, namely (a) poor molding accuracy of the protection plate and poor machining accuracy of the protection plate locking groove. It becomes difficult to mount and fix the plate perpendicularly to the inner and outer rings, (b) the mounting position of the protection plate changes due to thermal expansion of the protection plate, and (c) due to thermal expansion of the protection plate. , the outer ring is easily deformed in the direction of diameter expansion, etc., and is an extremely simple and robust method.
Moreover, it can be fitted perpendicularly to the inner and outer rings into the locking groove of the outer ring's protection plate, and the bearing manufacturing cost can be significantly reduced. The object of the present invention is to provide a plastic bearing protection plate that can prevent the occurrence of dust and has an excellent dustproof effect.

(Means for Solving the Problems) The present invention provides an outer circumferential edge having a substantially hemispherical cross section into a protection plate locking groove having a substantially inverted U-shaped cross section formed at the inner circumferential end of the outer ring. In the flange-shaped bearing protection plate that is designed to be fitted, the protection plate main body is connected to the hemispherical outer peripheral edge, and is continuous with the outer peripheral edge and is thinner than other parts in cross-sectional view. A flanged body made of plastic is provided with a thick wave-shaped curved portion and a flat plate portion continuous to the curved portion, and the outer peripheral edge fitted into the protective plate locking groove of the outer ring is engaged with the protective plate. The basic structure of the invention is to abut both side surfaces of the locking groove and to provide a gap between the inner peripheral surface of the deep part of the protective plate locking groove and the outer peripheral surface of the outer peripheral edge.

(Function) When the protection plate body 3 is applied to the outside of the bearing outer ring 1 and the outer circumference of the body is evenly pressed inward, the wave-shaped curved portion 7 of the protection plate body 3 is compressively deformed. The hemispherical outer peripheral edge 3a is fitted into the protective plate locking groove 2.

When the outer peripheral edge 3a is fitted into the locking groove 2, the diameter of the protection plate main body 3 expands due to the elastic force of the waveform curved portion 7, and the outer peripheral edge 3a is fixed into the locking groove 2. be done.

The hemispherical outer peripheral edge 3a comes into line contact with both side surfaces of the locking groove 2, which has an inverted U-shaped cross section, and a gap S remains at the inner part of the locking groove 2. That is, the outer peripheral edge 3a is fitted perpendicularly to the inner and outer rings by coming into contact with both side surfaces of the locking groove 2, and the outer ring 1 is fitted in the direction of the arrow () by the elasticity of the curved portion 7. F ₁ , F ₂ ) are applied.

Now, when the protective plate thermally expands, the acting force F ₁ ,
_F2 increases. However, the direction of its action hardly changes, and as a result, the force F that tries to spread the outer ring 1 does not become so large, and the damage and distortion of the outer ring 1 is reduced.

Further, even if thermal expansion occurs in the protection plate main body 3, the shape of the hemispherical outer peripheral edge 3a itself hardly changes. As a result, the line of contact between the outer peripheral edge 3a and the locking groove 2 hardly moves, and even if there is thermal expansion, the protective plate main body 3 is always held perpendicular to the outer ring 1, and the inner peripheral edge side does not move outward or inward.

Furthermore, even if the molding accuracy of the protection plate main body 3 and the processing accuracy of the locking groove 2 are slightly poor, the elastic force of the curved portion 7 acts radially evenly on the outer peripheral edge 3a, so that the hemispherical outer peripheral edge 3a is firmly pressed into the inverted U-shaped locking groove 2, and is firmly fixed to the outer ring 1 with extremely accurate perpendicularity.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a partial vertical cross-sectional view of a bearing equipped with a protection plate according to the first embodiment of the present invention. A protection plate locking groove with a cross section that is approximately inverted U-shaped (the cross section is approximately U-shaped in the lower part), 3 is a plastic protection plate main body, 4 is an inner ring, 5 is a ball, 6
is a retainer.

The protection plate main body 3 includes an outer circumferential edge 3a having a substantially hemispherical cross-sectional shape, a wave-shaped curved portion 7 that is continuous with the outer circumferential edge 3a and has approximately half the thickness of the other portion, and the curved portion 7. It is made of heat-resistant material such as hard nylon or polyacetate, and a continuous flat plate part 3b.
It is formed into a so-called brim-shaped body by integrally molding engineered plastic which has excellent wear resistance and appropriate elasticity.

The outer peripheral edge 3a of the protection plate main body 3 is shaped like the inverted U.
The protective plate is formed in a shape that forms a gap S between the outer peripheral surface of the outer peripheral edge 3a and the inner part of the locking groove 2 when the protective plate is fitted into the locking groove 2 of the present embodiment. In this case, the outer peripheral edge 3a has a substantially hemispherical cross-sectional shape. Therefore, the outer peripheral edge 3a of the protection plate main body 3 comes into contact with both side surfaces of the locking groove 2 when the outer ring 1 is fitted into the locking groove 2.

A substantially semicircular recess 8 having an appropriate radius of curvature is provided on the inner surface of the outer peripheral edge side of the brim-shaped protection plate main body 3.
The recessed portion 8 forms a curved portion 7 having a wavy cross-sectional shape in the main body 3 at a position continuous with the hemispherical outer peripheral edge 3a.

The thickness of the curved portion 7 is selected to be approximately half the thickness of the other portions. Therefore, the diameter of the protective plate is easily reduced due to the thin, corrugated curved portion 7, making it easy to fit and absorbing the expansion allowance when the temperature rises.

FIG. 2 shows a second embodiment of the present invention. In the first embodiment, by forming one recess 8, the brim-like protection plate main body 3 has a wave-shaped cross section. However, in the second embodiment, by providing two depressions 8, 8 on the inner and outer surfaces of the protection plate main body 3, the wave-shaped curved portion 7 is formed.
I am trying to form a .

3 and 4 show third and fourth embodiments of the present invention, in which a sealing piece 9 is formed at the inner peripheral end of the protection plate main body 3. That is, a recess 10 having an appropriate depth and a substantially semicircular cross section is formed on the outer surface of the inner ring side end of the protection plate main body 3. A thin sealing piece 9 having extremely thin elasticity is formed in the radial direction at the end.

The tip end 9a of the seal piece 9 is always in light contact with the edge of the outer peripheral surface of the inner ring 4 when it is fitted onto the outer ring 1, thereby achieving more complete dustproofing. . Furthermore, if the expansion amount of the protection plate main body 3 cannot be fully absorbed by the curved portion 7, the seal piece 9 is designed to absorb the remainder.

Next, the case where the plastic bearing protection plate according to the present invention is attached to the outer ring 1 will be explained.

When installing the protection plate, first, the protection plate main body 3 is applied to the outside of the bearing outer ring 1, and the outer circumference of the main body 3 is evenly pressed inward. Then, the curved portion 7 of the protective plate main body 3 is bent due to the elasticity of the material itself, and the diameter is slightly reduced in the radial direction, and the outer peripheral edge 3a is fitted into the locking groove 2 of the outer ring 1. .

At this time, the outer peripheral edge 3a of the protection plate main body 3 comes into line contact with both side surfaces of the locking groove 2 of the outer ring 1, and is fitted into the outer ring 1 in a substantially perpendicular manner.

Further, the seal piece 9 of the protection plate main body 3 has its tip 9a always in contact with the inner ring 4 side with extremely weak elasticity, and comes into rotational contact with the inner ring 4.

(Effects of the invention) Since the present invention has the above configuration, it has the following advantages.

(1) The protection plate main body 3 has a wave-shaped curved part 7 at the inside position of the outer peripheral edge and its thickness is thinner than other parts, so when the protection plate is attached to the outer ring, Place the protective plate body 3 towards the
If the outer periphery of the main body 3 is evenly pressed inward, the diameter of the protection plate will be reduced without any force, making it extremely easy to attach the outer ring to the locking groove 2.

(2) Once the outer peripheral edge 3a of the protective plate main body is fitted into the locking groove 2, the elasticity of the curved portion 7 presses the outer peripheral edge 3a toward the locking groove 2, and the protective plate is held extremely tightly. Moreover, it is fixed firmly and perpendicularly to the outer ring. the result,
There is no chance that the protective plate body will fall off or rattle during use of the bearing, causing noise.

Furthermore, even if a temperature change occurs in the protection plate main body 3 while the bearing is in use, the expansion and contraction caused by the temperature change will be sufficiently absorbed within the curved portion 7, thereby preventing the protection plate from shaking due to temperature changes. Sticking is prevented.

(3) Since the outer peripheral edge 3a of the protection plate main body 3 is formed into a substantially hemispherical shape and is fitted into the locking groove 2 having an inverted U-shaped cross section, the curved portion may be formed due to thermal expansion or the like. Even if the elastic force of the outer ring 7 changes, the linear contact portion between the outer peripheral edge 3a and the locking groove 2 will not be displaced, and as a result, the protection plate main body 3 will always be held perpendicular to the outer ring. be done.

(4) The outer peripheral edge 3a of the protection plate main body 3 is formed into a substantially hemispherical shape, and when this is fitted into the locking groove 2 of the outer ring, the outer peripheral surface of the outer peripheral edge and the deep part of the locking groove 2 A gap S is provided between them so that the outer peripheral edge 3a comes into contact with both side surfaces of the locking groove 2. As a result, a force in a direction oblique to the axis acts on the outer ring 1, a force in a direction perpendicular to the axis decreases, and deformation of the outer ring 1 is prevented. That is, even if the protective plate is fitted, the roundness of the outer ring 1 will hardly decrease.

(5) Outer peripheral edge 3a of the protection plate main body 3 having a hemispherical cross section
is pushed into the locking groove 2 having an inverted U-shaped cross section by the elastic force of the curved portion 7, and the outer peripheral edge 3a
Since a gap S is provided between the inner part of the locking groove 2 and the inner part of the locking groove 2, the elastic force of the curved part 7 is presses the outer circumferential edge 3a radially and evenly, and the hemispherical outer circumferential edge 3a is firmly fixed in the locking groove 2 with accurate perpendicularity to the outer ring 1. . In other words, the protection plate does not require high processing accuracy and is easy to process.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view of a bearing equipped with a plastic bearing protection plate according to the first embodiment of the present invention, and Figure 2 is a partial cross-sectional view of a bearing equipped with a plastic bearing protection plate according to the second embodiment of the invention. FIGS. 3 and 4 are partial longitudinal sectional views of a bearing equipped with a protection plate according to another embodiment of the present invention. FIG. 5 is a longitudinal cross-sectional view of a conventional plastic bearing protection plate.
FIG. 6 is a partial vertical sectional view of a bearing equipped with a conventional plastic protection plate. 1 is the outer ring, 2 is the locking groove, 3 is the protective plate body, 3a
3b is a flat plate portion, 4 is an inner ring, 7 is a curved portion, and S is a gap.

Claims (1)

[Scope of utility model registration request] A flange-shaped bearing in which an outer circumferential edge 3a having a substantially hemispherical cross section is fitted into a protective plate locking groove 2 having a substantially inverted U-shaped cross section formed on the inner circumferential side end of an outer ring 1. In the protection plate for use, the protection plate main body 3 is
The hemispherical outer peripheral edge 3a, a wavy curved part 7 continuous with the outer peripheral edge 3a and having a thickness thinner than other parts, and a flat plate part 3b continuous with the curved part 7.
It is a flanged body made of plastic and has an outer ring 1.
The outer peripheral edge 3a fitted into the protective plate locking groove 2 of
is in contact with both side surfaces of the protective plate locking groove 2, and a gap S is provided between the deep inner peripheral surface of the protective plate locking groove 2 and the outer peripheral surface of the outer peripheral edge 3a. protection plate.