CA1086363A

CA1086363A - Bearing

Info

Publication number: CA1086363A
Application number: CA300,744A
Authority: CA
Inventors: Donald A. Coil; John L. Johnson, Jr.; Horace J. Swinland
Original assignee: Caterpillar Tractor Co
Current assignee: Caterpillar Inc
Priority date: 1977-07-07
Filing date: 1978-04-10
Publication date: 1980-09-23
Also published as: DE2829792A1; DE2829792C2; HK72783A; GB1559567A; JPS5417448A

Abstract

BEARING

Abstract of the Disclosure A bearing has a body, a surface and a tab extend-ing from the body. The tab is of a construction sufficient for insertion of the bearing into a preselected cavity only with the bearing surface oriented in a preselected direction.

Description

1~86363 Machine assemblies, such as an automotive crankshaft and journal bearing assembly for example, frequently incorporate thrust bearings for limiting axial motion. The thrust bearing is inserted in a cavity between the crankshaft, engine block and ~`
main journal bearing to limit motion along the axis of rotation of the crankshaft. The thrust bearing has two faces with bearing surface material on one surface only. The bearing is sometimes inadvertently inserted incorrectly with the bearing surface material to~ards the engine block surface which is stationary relative to the thrust bearing instead of the crankshaft thrust face or cheek which moves relative to the bearing. This damages the crankshaft and bearing.
It is desirable to have a bearing which has bearing surface material only on one surface, but which cannot be inserted incorrectly.
To this end, according to the present invention, an assembly comprises first and second relatively rotatable members, each of hhich has a radially extending and axially directed sur-face, the surfaces being directed towards each other and defin-ing a cavity between them, the cavity having a portion of reduced cross-sectional area, and a thrust bearing in the cavity, the bearing comprising a body having a periphery and a bearing surface, and a tab extending from the periphery adjacent the bearing surface, thetabbeing so dimensioned and arranged that it lies in the portion of the cavity of reduced cross-sectional area with the bearing surface directed towards one of the two axially

- 2 -facing surfaces and the tab preventing the bearing from being inserted into the cavity with the bearing surface towards the other of the two axially facing surfaces, and the tab also being spaced from the first and second members in the portion of the cavity of reduced cross-sectional area when the body of the bearing is in contact with the other of the two axially facing surfaces.
Three examples of thrust bearing assemblies in accordance with the invention incorporated in an automotive crankshaft assembly are illustrated in the accompanying drawings, in which:-Figure 1 is a side view of part of the crankshaftwith the bearing assembly in section;
Figure 2 is an isometric view of one example of the thrust bearing;
Figure 3 is a cross-sectional view similar to part of Figure 1, but to a larger scale;
Figure 4 is a view similar to Figure 2, but of a second example of the bearing;
Figure 5 is a cross-section view similar to Figure 3 but of a second example; and Figure 6 is a cross-sectional view similar to Figure 3 but of a third example.
Referring to Figure 1, a crankshaft 10, a main journal bearing 12 and part 14 of an engine block define between them a cavity 16. The block 14 has a protrusion 18 which extends toward a lobe 19 ~ !

~086363 and cheek or thrust face 20 of the crankshaft 10.
The journal bearing 12 is held in the block 14 and preferably has its ends generally flush therewith (Figure 3). ~lternatively an end portion 13 of the 5. bearing 12 can extend to a location generally flush with the protrusion 18 (Figures 5, 6). The shape of the cavity 16 is influenced by the relationship of the bearing 12, the crankshaft cheek 20 and the block 14.
10. Referring to Figures 2 and 3, a bearing 21, preferably a thrust bearing like a washer, is positioned in the cavity 16. The bearing 21 has a body portion 22, a bearing surface 24, inner and outer peripheries 26, 28 and at least one tab 30 adjacent the surface 24.
15. The tab 30 preferably extends outwardly from the outer periphery 28 in opposed relation to the inner periphery 26. m e tab 30 is preferably of a smaller cross-sectional dimension than the body 22 of the bearing 21 and is shaped for insertion of the bearing 21 into the cavity 16 with 20. the surface 24 oriented only toward the crankshaft cheek 20 defining the cavity 16. The tab 30 prevents insertion in any other manner by abutting the protrusion 18 and . preventing the body 22 of the bearing 21 from entering the cavity 16.

~`

,--1C~86363 The tab 30 abuts the washer surface 24 which is pre-ferably a bearing surface. The tab 30 and washer 21 are preferably constructed of steel and the surface 24 is preferably bonded bearing material such as aluminum. The tab 30 is spaced a preselected distance from the engine block protrusion 18 when the ~asher body 22 and engine block 14 are in abutting contact.
The ~asher 21 has an arcuate configuration, preferably semi-circular, and has first and second end portions 32, 34 ~Figure 2, 4). The end portions 32, 34 are preferably tapered.
The tab 30 is preferabl~ spaced a preselected distance from the end portions 32, 34. The tab 30 can extend radially outward from the outer peripheral surface 28 or inwardly from inner peripheral surface 26, spaced from the first end portion 32 and the second end portion 34. There can be more than one tab 30.
~eferring to Figures 4 - 6, the tab 30 can extend in~ardly from the inner peripher~ 26 in opposed relation to the outer peripher~ 28. The tab 30 can be tapered adjacent the surface 24 and the body 22 can be tapered adjacent the tab 30.
In operation, an assembler inserts the thrust bearing 21 into the cavity 16 with the surface 24 adjacent the crankshaft cheek 20. If the assembler attempts to insert the thrust bearing 21 with the bearing surface 24 adjacent the engine block 14, the tab 30 abuts the engine block protrusion 18 or the journal bearing end portion 13 and prevents incorrect insertion.
Other aspects, objects and advantages will become apparent from a study of the specification, drawings and appended claims.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An assembly comprising first and second relatively rotatable members, each of which has a radially extending and axially directed surface, the surfaces being directed towards each other and defining a cavity between them, the cavity having a portion of reduced cross-sectional area, and a thrust bearing in the cavity, the bearing comprising a body having a periphery and a bearing surface, and a tab extending from the periphery adjacent the bearing surface, the tab being so dimensioned and arranged that it lies in the portion of the cavity of reduced cross-sectional area with the bearing surface directed towards one of the two axially facing surfaces and the tab preventing the bearing from being inserted into the cavity with the bearing surface towards the other of the two axially facing surfaces, and the tab also being spaced from the first and second members in the portion of the cavity of reduced cross-sectional area when the body of the bearing is in contact with the other of the two axially facing surfaces.

2. An assembly according to Claim 1, in which the body of the bearing has inner and outer peripheries and said tab extends inwardly from said inner periphery in opposed relation to said outer periphery.

3. An assembly according to Claim 1, in which the body of the bearing has inner and outer peripheries and said tab extends outwardly from said outer periphery in opposed relation to said inner periphery.

4. An assembly according to Claim 1,wherein said tab is tapered adjacent said bearing surface.

5. An assembly according to Claim 4,in which the bearing is arcuately shaped and has first and second end portions.

6. An assembly according to Claim 5, wherein said tab is peripherally spaced a preselected distance from said end portions.

7. An assembly according to Claim 5 or Claim 6, wherein said end portions are tapered.

8. An assembly according to any one of claims 1 through 3, wherein said body is tapered adjacent said tab.

9. An automotive crankshaft assembly comprising a crankshaft having a cheek, a main journal bearing rotably supporting the crankshaft and an engine block supporting the main journal bearing, wherein the cheek forms the first relatively rotatable member of an assembly in accordance with any one of claims 1 through 3, and a part of the engine block forms the second of the relatively rotatable members, the bearing surface of the thrust bearing being directed towards the cheek.