JPH0412257Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a bearing structure that rotatably supports a shaft such as a crankshaft.

[Conventional technology]

FIG. 3 shows a crank press, and in the figure, reference numeral 11 indicates a crankshaft disposed in the crown portion 15 of the press machine 13. As shown in FIG.

This crankshaft 11 has a flywheel 1
9, a clutch 21 and a brake 23 are arranged.

Rotation of a motor 25 is transmitted to the crankshaft 11 via a drive mechanism (not shown).

The crankshaft 11 is supported by a plurality of bearings 27, and one end of a connecting rod 31 is connected to the crank portion 29 of the crankshaft 11.
A slide 33 of the press machine 13 is connected to the other end of the connecting rod 31.

A bolster 37 is disposed below the slide 33 and supported by a bed 35.

In the crank press configured as above,
As the crankshaft 11 rotates, the connecting rod 31 moves up and down, and the slide 33 moves up and down.
is moved up and down along the column 39, and the slide 33
is fitted into the bolster 37, and press working is performed.

[Problem that the invention attempts to solve]

In such a crank press, a large load is instantaneously applied to the slide 33 during press working, that is, when the slide 33 is fitted to the bolster 37. A high load will also temporarily act on the bearing 27 portion.

4 and 5 show a conventional bearing 27, in which an outer race 41
A rolling element 45 is interposed between the inner race 43 and the inner race 43, and the crankshaft 11 to be supported is inserted through the inner race 43. In addition, the rolling element 4
5 is supported by a retainer 47.

In this bearing 27, the amount of deformation due to the operating load rating of the rolling elements 45 in consideration of a predetermined life is δ1, the amount of deformation due to the static load rating, which is the limit load at which plastic deformation occurs in the rolling elements 45, is δ2, and the amount of deformation due to the static load rating, which is the limit load at which plastic deformation occurs in the rolling elements 45, is δ2. Moving object 4
5 and the outer race 41 is δ3.

When a high load is temporarily applied to such a bearing 27, a load higher than the static load rating acts on the rolling elements 45, plastic deformation occurs in the rolling elements 45, and the rolling elements against the inner race 43 and outer race 41 are There is a possibility that plastic deformation will occur on the raceway surfaces 48 and 49 of the 45.

Therefore, conventionally, in order to prevent plastic deformation of the raceway surfaces 48, 49 and rolling elements 45 of the bearing 27 due to this temporary high load, it has been necessary to increase the size and number of the bearing 27.

[Purpose of invention]

The present invention solves the above-mentioned problems, and aims to provide a bearing structure that can reliably prevent plastic deformation of the bearing raceway and rolling elements due to temporary high loads. .

[Means for solving problems]

In the bearing structure according to the present invention, a large diameter hole and a small diameter hole are formed in the bearing member so as to be aligned with the axis, a metal part is formed on the inner surface of the small diameter hole, and an outer race and an inner race are formed in the large diameter hole. The outer race of a rolling bearing with a rolling element interposed between them is inserted, and the dimension C obtained by subtracting the inner radius of the inner race from the inner radius of the metal part is the usage rating of the rolling element. When the amount of deformation due to load is δ1, the amount of deformation due to static load rating is δ2, and the dimension of the gap formed between the rolling element and the outer race under no load is δ3, the dimension satisfies δ1+δ3<C<δ2+δ3. This is what I did.

[Effect of invention]

In this invention, a large diameter hole and a small diameter hole are formed in the bearing member with the same axis, a metal part is formed on the inner surface of the small diameter hole, and a rolling element is formed in the large diameter hole between the outer race and the inner race. Insert the outer race of the rolling bearing with the
Dimension C is calculated by subtracting the inner radius of the inner race from the inner radius of the metal part, δ1 is the amount of deformation due to the rated load of the rolling element, δ2 is the amount of deformation due to the static load rating, and the distance between the rolling element and the outer race when no load is applied. When the dimension of the gap formed between the two is δ3, the dimension is set such that δ1+δ3<C<δ2+δ3, so the deformation of the bearing is δ2+δ3
When the above temporary high load is applied, the metal part comes into contact with the shaft inserted into the inner race of the bearing, and this contact causes the load to be supported by the metal part of the bearing member, causing the raceway surface of the bearing to And it becomes possible to reliably prevent plastic deformation of the rolling elements.

On the other hand, during normal loading, the deformation of the bearing is
is less than δ2+δ3, the metal portion does not come into contact with the shaft inserted into the inner race of the bearing, and the load is supported by the rolling elements, allowing the bearing to rotate smoothly.

[Example of idea]

Hereinafter, details of the present invention will be described with reference to an embodiment shown in the drawings.

1 and 2 show an embodiment of the bearing structure of the present invention, and in these figures, reference numeral 51 indicates a bearing member that constitutes a frame bearing of a press machine, for example. .

This bearing member 51 has a large diameter hole 53 and a small diameter hole 55 formed with the same axis. For example, the small diameter hole 55 has a metal part 5 made of bronze on its inner surface.
7 is formed. An outer race 59 of a rolling bearing 63 having a rolling element 61 interposed between an outer race 59 and an inner race 60 is fitted into the large diameter hole 53 formed on both sides of the small diameter hole 55 .

In addition, the inner race 60 of the rolling bearing 63
And the outer race 59 is formed with arc-shaped raceway surfaces 67 and 69, and these raceway surfaces 6
A rolling element 61 is rotatably arranged between 7 and 69. Further, the rolling elements 61 are supported by a retainer 71.

In addition, in this rolling bearing 63, the amount of deformation due to the operating load rating of the rolling element 61 considering a predetermined life is δ1, the amount of deformation due to the static load rating, which is the limit load at which plastic deformation occurs in the rolling element 61, is δ2, and the amount of deformation due to the unloaded load is δ2. The gap dimension formed between the rolling element 61 and the outer race 59 at this time is δ3.

Therefore, in the bearing structure of this embodiment, the inner radius of the metal portion 57 is larger than the inner radius of the inner race 60 by a minute dimension C.

This minute dimension C is set to a dimension that satisfies δ1+δ3<C<δ2+δ3 with respect to δ1, δ2, and δ3 described above.

In the bearing structure configured as described above, the large diameter hole 53 and the small diameter hole 55 are formed in the bearing member 51 with the same axis, the metal part 57 is formed on the inner surface of the small diameter hole 55, and the large diameter hole 53 is formed with the same axis. To, outer lace 5
The outer race 5 of a rolling bearing 63 has a rolling element 61 interposed between the outer race 5 and the inner race 60.
9, and further subtract the inner radius of the inner race 60 from the inner radius of the metal part 57, which is the dimension C.
When the amount of deformation due to the operating load rating of the rolling element 61 is δ1, the amount of deformation due to the static load rating is δ2, and the gap dimension formed between the rolling element 61 and the outer race 59 at no load is δ3, Since the dimensions are such that δ1+δ3<C<δ2+δ3, when a temporary high load is applied to the rolling bearing 63 causing deformation of δ2+δ3 or more, the metal portion 57 of the bearing member 51 will, for example,
The metal portion 57 of the bearing member 51 abuts against the crankshaft 73, and due to this abutment, the load is supported by the metal portion 57 of the bearing member 51.
And it becomes possible to reliably prevent plastic deformation of the rolling elements 61.

As a result, a high load can be easily supported by the rolling bearing 63, which is smaller than the conventional one.

On the other hand, during normal load application, the rolling bearing 6
The deformation of No. 3 is less than δ2 + δ3, the metal portion 57 of the bearing member 51 does not come into contact with the crankshaft 73, the load is supported by the rolling elements 61, and the bearing rotates smoothly.

In the embodiments described above, the present invention was applied to radial ball bearings, but the present invention is not limited to such embodiments. For example, the present invention is applicable to roller bearings, taper bearings, needle bearings, etc. Needless to say, the present invention can be applied to other types of bearings, as well as thrust bearings.

[Effect of idea]

As described above, according to the present invention, a large diameter hole and a small diameter hole are formed in the bearing member with the same axis, a metal part is formed on the inner surface of the small diameter hole, and an outer race and an inner race are formed in the large diameter hole. Insert the outer race of a rolling bearing with a rolling element between them, and then calculate the dimension C, which is the inner radius of the metal part minus the inner radius of the inner race, and the amount of deformation due to the rated load of the rolling element. When δ1 is the amount of deformation due to the static load rating, δ2 is the gap formed between the rolling element and the outer race under no load, and δ3 is the dimension that satisfies δ1+δ3<C<δ2+δ3, the bearing raceway There is an advantage that plastic deformation of the surface and the rolling elements can be reliably prevented.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing an embodiment of the bearing structure of the present invention, Fig. 2 is a longitudinal cross-sectional view showing an enlarged main part of Fig. 1, and Fig. 3 is a longitudinal cross-sectional view showing a press machine. ,
FIG. 4 is a vertical cross-sectional view showing a conventional bearing, and FIG. 5 is a vertical cross-sectional view showing a part of the bearing shown in FIG. 4 in an enlarged manner. 51...Bearing member, 53...Large diameter hole, 55...
Small diameter hole, 57...metal part, 59...outer race, 60...inner race, 61...rolling element, 63...rolling bearing.

Claims (1)

[Claims for Utility Model Registration] A large diameter hole and a small diameter hole are formed in the bearing member with the same axis, a metal part is formed on the inner surface of the small diameter hole, and an outer race and an inner race are formed in the large diameter hole. The outer race of a rolling bearing with a rolling element interposed between them is inserted, and the dimension C obtained by subtracting the inner radius of the inner race from the inner radius of the metal part is the operating load rating of the rolling element. When the amount of deformation due to the static load rating is δ1, the amount of deformation due to the static load rating is δ2, and the gap dimension formed between the rolling element and the outer race under no load is δ3, the dimensions were set such that δ1+δ3<C<δ2+δ3. The bearing structure is characterized by: