GB2207961A

GB2207961A - Flanged bush

Info

Publication number: GB2207961A
Application number: GB08818095A
Authority: GB
Inventors: Yoshio Iijima
Original assignee: Daido Metal Co Ltd
Current assignee: Daido Metal Co Ltd
Priority date: 1984-07-26
Filing date: 1987-07-16
Publication date: 1989-02-15
Also published as: GB8818095D0; GB2193268B; GB2193268A; GB2207961B; GB8716795D0

Abstract

A flanged bush (45) comprises a generally cylindrical sliding section having at one end thereof an integrally-formed outwardly radially-extending flange. The sliding section is lined with a bearing material which also covers the end axial face of the flange. An external groove forming a stress relieving groove is provided at the junction of the flange and the cylindrical section. The bush may be formed with or without an axial seam. <IMAGE>

Description

A Flanged Bush and a Method of and Apparatus for Producing a Flanged Bush The present invention relates to a flanged bush and a method of and an apparatus for producing flanged bushes (which may for example be used as sliding parts for bearing both axial thrust load and radial load in various industrial machines).

Hitherto, a flanged bush of the kind described has been produced by preparing a cylindrical bush and a thrust washer separately, and fixing the thrust washer to the cylindrical bush by means of a pin or by means of adhesion or welding.

This conventional method, however, is generally difficult to conduct and suffers from low precision, due to separate formation of the cylindrical bush and the washer, resulting in a lengthy and expensive production process.

Accordingly, an object of the invention is to provide a method and an apparatus for producing flanged bushes which are improved to alleviate or overcome the above-described problem of the prior art.

To this end, according to one aspect of the invention, there is provided a method of producing flanged bushes comprising: inserting a generally cylindrical stock into a through bore formed in a die, and axially compressing the stock to cause it to conform with the throughbore, thereby forming a flange.

According to another aspect of the invention, apparatus for producing a flanged bush comprises a die having a throughbore formed therein, means for inserting a generally cylindrical stock into the throughbore, and means for axially compressing the stock to cause it to conform with the throughbore, thereby forming a flange.

According to a further aspect of the invention apparatus for producing a flanged bush comprises: a die having a through bore having a configuration conform ing with the configuration of said flanged bush; a coining punch device disposed at one axial end of said die and adapted to insert a generally cylindrical stock into said bore in said die; and a flange-forming punch device disposed at the other axial end of said die and adapted to press the inner end of said cylindrical stock in said bore in cooperation with said coining punch device so as to form a flange.

According to yet a further aspect a flanged bush comprises a generally cylindrical sliding section having at one end thereof an integrally-formed outwardly axiallyextending flange. The stock from which such a bush is made may, but need not, have a seam.

The above and other objects, features and advantages of the invention will become clear from the following description of the preferred embodiments when the same is read in conjunction with the accompanying drawings; in which: Figure 1 is a schematic illustration of a first embodiment of an apparatus of the invention for producing a flanged bush; Figure 2 is a schematic illustration of a second embodiment of the apparatus of the invetnion for producing a flanged bush; Figure 3 is a perspective view of a flat sheet from which a flanged bush is produced in accordance with a method of the invention; Figures 3B and 3C are perspective views of cylindrical stocks of flanged bushes with and without a side seam, respectively; Figures 3D to 3G are sectional views of various cylindrical stocks;; Figures 4A to 4F are illustrations of steps of a process for forming flanged bushes from cylindrical stocks; Figures 5A and SB are perspective views of flanged bushes with and without a side seam, respectively; and Figures 5C to 5F are sectional views of flanged bushes fromed from various types of stocks.

Referring first to Figure 1, a first embodiment of the apparatus for producing a flanged bush in accordance with the inveniton is generally designated by a reference numberal 10. The apparatus 10 includes a die 1 carried by a frame (not shown), a coining punch device 2 and a flange-forming punch device 11. The coining punch device 2 includes a coining punch 3 to be moved axially in a bore lc (see Figure 4A) of a small diameter formed in the die 1, a coining punch slider 4 connected to this coining punch and a cam-type actuator 5. The coining punch slider 4 is reciprocatably received in a sleeve bearing 6 which is fixed to a coining frame 7.The flange-forming punch device 11 includes a flangeforming punch 12 adapted to reciprocatingly move in a large bore la (see Figure 4a) formed in the die 1, a flange-forming punch slider 13 connected to the flangeforming punch 12, and a crank or cam-type actuator 16 for actuating the punch slider. The flange-forming punch slider 13 is reciprocatably received in a sleeve bearing 14 fixed to a flange-forming frame 15.

As may be seen in Figure 4A, in addition to the aforementioned small and large bores ic and la, a frustconical bore 1b continuing from the large bore la is formed in the die 1. These bores la, lb and lc in combination provide a cavity which conforms with the outer configuration of the finished flanged bush.

Referring now to Figure 2, a second embodiment of the apparatus for producing a flanged bush in accordance with the invention is denoted generally by a reference numeral 10'. This embodiment 10' is distinguished from the first embodiment 10 in that it employs a plurality of dies 1 carried by an indexing device 20, and hence is suited to mass-produ-=tion of flanged bushes. The indexing device 20 has an indexing table 21 carrying a plurality of dies 1 arranged at a constant angular interval, and an indexing mechanism 22 which is operatively connected to the coining punch device 2 and the flangeforming punch device 11 so as to rotate the indexing table 21 repeatedly by a predetermined angle.A means (not shown) for supplying cylindrical stocks of the flanged bush and means (also not shown) for taking out the products are arranged in the vicinity of the indexing table 21.

Figures 3B to 3G show examples of cylindrical stocks for use in the production of the flanged bush.

More specifically, figure 3B shows a cylindrical stock of a bush 31 having a side seam 31a, formed by bending a flat sheet 30 (as shown in Figure 3A). Figure 3C shows a stock 32 having no seam, prepared by, for example, forging, drawing, cutting, pouring or centrifugal casting.

These cylindrical stocks can have vertical sections as shown in Figures 3D to 3G. The cylindrical stock 33 shown in Figure 3D is made of a ferrous and nonferrous homogeneous material having good slidability.

The cylindrical stocks 34, 35, 36 shown in Figures 3E to 3G have bi-metallic or multi-layer structures composed of cylindrical ferrous carries 34a, 35a, 36a lined with layers 34b, 35b, 36b of a bearing metal. Notches 34c, 35c, 36c are formed as desired in the outer or inner peripheral surfaces.

Figures 4A to 4F illustrate a process for forming a collared bush by the apparatus of the invention.

In the step shown in Figure 4A, a cylindrical stock S is driven into the small bore 1c in the die 1 from the right side end of the die 1 by means of the coining punch 3. When the apparatus shown in Figure 2 is used, the cylindrical stocks S are fed from the stock feeder (not shown) to the dies 1 carried by the indexing table 21 of the indexing device 20, and are successively brought, upon rotation of the indexing table, to a position where the die 1 is aligned with the coining punch 3 and the flange-forming punch 12. As shown in Figure 4A, the brim of the entrance-side end of the small bore 1c formed in the die 1 is tapered at an angle 1 to facilitate the insertion of the cylindrical stock.

This angle Q1 may be between 0O and 900, and is preferably between 110 and 50 In a step shown in Figure 4B, the cylindrical stock S received in the small bore Ic in the die 1 is forcibly moved to the left by the coining punch 3.

Referring now to Figure 4C, the flange-forming punch 12 starts to move to the right, while the cylindrical stock S is further moved to the left in the die 1.

In the step shown in Figure 4D, the flange-forming punch 12 is further moved to the right until its reduced-diameter portion 12a comes into the cylindrical stock S. It is to be noted that the reduced-diameter portion 12a of the flange-forming punch 12 has a diameter which is slightly smaller than the inside diameter of the cylindrical stock S.

In the next step, shown in Figure 4E, the coining punch 3 and the flange-forming punch 12 are further moved to the left and to the right, respectively, so that the left end of the stock S is expanded radially outwardly as it is pressed by a step on the flangeforming punch 12.

In the final step, shown in Figure 4F, the left end portion of the cylindrical stock S is pressed by the flange-forming punch 12 so that the expanded extremity of the stock is compressed radially along the frustoconical bore lb of the die 1, while the cylindrical portion of the stock S is compressed axially by the coining punch 3. Consequently, the cylindrical stock S is formed into a flanged bush having an outer configuration conforming with the shape of the cavity defined by the small bore 1c and the frust-conical bore 1b in the die 1. As shown in Figure 4F, the frustconical bore 1b in the die 1 has a conical angle e2 which may be between 0 and 90 , and is preferably between 300 and 450.

Figures 5A to 5F show flanged-bushes 40-45 which are formed from the cylindrical stock S by the production apparatus 10 or 10' of the invention. More specifically, Figure 5A shows a flanged bush 40 having a seam 40a, manufactured from the seamed cylindrical stock 31 shown in Figure 3B, while Figure 5B shows a flanged bush 41 made from the seamless cylindrical stock 32 shown in Figure 3C. Figures 5C to 5F show, respectively, flanged bushes 42 to 45 formed from cylindrical stocks 33 to 36 shown in Figures 3D to 3G.

Claims

Claims:

1. A method of producing a flanged bush comprising: inserting a generally cylindrical stock into a through bore formed in a die, and axially compressing the stock to cause it to conform with the throughbore, thereby forming a flange.

2. A composite flanged bush substantially as specifically described, with reference to Figure 5C.

2. A method as claimed in claim 1 in which the flange is formed by pressing at least part of the stock between the throughbore and an axially-movable flange-forming punch.

3. A method as claimed in claim 2 in which the flange is first partially formed by pressing the stock against the flange-forming punch.

4. A method as claimed in claim 1 or claim 2 or claim 3, in which the stock is inserted into one end of the throughbore, and the flange is formed at the other end.

5. A method of producing a flanged bush comprising inserting a generally cylindrical stock into one end of a throughbore formed in a die, inserting an axiallymovable flange-forming punch into the throughbore and stock from the other end thereof, axially pressing the stock against the flange-forming punch so as partially to form a flange, and completing the flange by pressing it between a shoulder formed in the throughbore and the flange-forming punch.

6. A method of producing a flanged bush substantially as specifically described herein with reference to Figures 4B to 4F.

7. Apparatus for producing a flanged bush comprising a die having a throughbore formed therein, means for inserting a generally cylindrical stock into the throughbore, and means for axially compressing the stock to cause it to conform with the throughbore; thereby forming a flange.

8. Apparatus as claimed in claim 7 in which the axial compressing means is a flange-forming punch axiallymovable within the throughbore and arranged to form the flange between itself and a shoulder formed in the throughbore.

9. Apparatus as claimed in claim 7 or claim 8 in which the inserting means is cam-operated.

10. Apparatus as claimed in any one of claims 7 to 9 in which the axial compressing means is cam-operated.

11. Apparatus as claimed in any one of claims 7 to 10 including an indexing table carrying a plurality of dies, means for inserting stock into one of the dies in a first position, means for rotating the indexing table to a second operative position, in which the flange is formed, and for rotating it into a third position, and means for removing the finished bush.

12. An apparatus for producing a flanged bush comprising: a die having a throughbore having a configuration conforming with the configuration of said flanged bush; a coining punch device disposed at one axial end of said die and adapted to insert a qenerally cylindrical stock into said bore in said die; and a flange-forming punch device disposed at the other axial end of said die and adapted to press the inner end of said cylindrical stock in said bore in cooperation with said coining punch device so as to form a flange.

13. Apparatus for producing a flanged bush substantially as specifically described herein with reference to Figure 4A, and to Figure 1 or to Figure 2.

14. A flanged bush comprising a generally cylindrical sliding section having at one end thereof an integrallyformed outwardly ra#ally-extending flange.

15. A bush as claimed in claim 14 in which the sliding section is lined with a bearing material.

16. A bush as claimed in claim 15 in which the end axial face of the flange is also covered with the bearing material.

17. A bush as claimed in any one of claims 14 to 16 in which the outer edge of the flange is chamfered with respect to the bush axis.

18. A bush as claimed in claim 17 in which the chamfer angle lies between 300 and 450.

19. A flanged bush substantially as specifically described herein with reference to either Figure SA or 5B, and any one of Figures 5C to 5F.

AMENDED CLAIMS

1. A composite flanged bush capable of having been formed by compression of a generally cylindrical hollow composite stock comprising an external support member having a circumferential external groove therein and an internal hollow cylindrical sliding member secured thereto, the formed bush being such that the external support member has a cylindrical body portion and an outwardly-extending flange at one end thereof, said flange having a flat end surface, the sliding member covering substantially entirely an axial inner bore of the bush and the said end surface, and the external groove forming a stress-relieving groove at the junction of the body portion and the flange.