AN ARRANGEMENT FOR LOCKING A SHAFT TO A MACHINE MEMBER

Abstract: The invention relates to an arrangement for locking a shaft or an axle to a machine member. The shaft has a central cylindrical part (8) which is intended to carry a bearing. The arrangement includes two expander sleeves (9, 10) which have a conical internal shape and each of which is intended to be mounted on a respective end of the shaft of similar conical shape. The expander sleeves (9, 10) function as annular wedges with the apex of the wedge facing towards the cylindrical part (8) of the shaft or axle and when tightening a nut (6) are caused to expand against the machine member and therewith lock the shaft thereto. The shaft comprises an outer sleeve (1) which presents the conically shaped end-parts, and a pin (2) which is arranged coaxially with and within the sleeve (1) and one end of which has an outwardly curved, mushroom-headed end-part (3) whose radially inward surface is intended to abut an adjacent second expander sleeve, and the other end (5) of which pin (2) carries the nut (6) with which the first and second expander sleeves (9, 10) are caused to expand into clamping contact with the machine member (11, 12) when tightening the nut.

Description: An arrangement for locking a shaft to a machine member The present invention relates to an arrangement for locking a shaft or an axle to a machine member, said shaft being intended to carry a bearing on a central cylindrical part thereof. The arrangement includes first and second expander sleeves which have conical internal form and each of which is located on a respective end of corresponding configuration on the shaft. The expander sleeves function as annular wedges with the apex of the wedge facing towards the cylindrical part of the shaft or axle and when tightened with the aid of tightening means can be caused to expand against the machine member and therewith lock the shaft thereto. An arrangement of this kind intended for locking a shaft or an axle to the attachment lugs of a machine member is known from Swedish Published Specification 435 953. One drawback with this known locking arrangement is that locking is effected through the medium of two nuts mounted on respective ends of the shaft and that when the shaft is located in a confined space, it is diffi¬ cult to reach the nuts in order to tighten the same. Accordingly, it is an object of the present invention to provide an improved arrangement for locking a shaft or an axle to a machine member where solely one end of the shaft need be accessible in order to clamp or lock the shaft to said machine member. The inventive arrangement is characterised in that the shaft comprises an outer sleeve, which presents the conically shaped end-parts, and a pin which is arranged coaxially with and within the sleeve and one end of which has an outwardly curved, mushroom-headed end-part whose radially inward surface abuts an associated ex- pander sleeve, and the other end of which pin carries the fastener means with which the expander sleeves are caused to expand into clamping contact with the machine member. The invention will now be described in more detail with reference to the accompanying drawing, the single Figure of which illustrates a preferred embodiment of the invention in perspective and partly in section. The illustrated embodiment of the inventive arrangement includes an axle or shaft which comprises an outer sleeve 1 and a pin 2 which extends within the sleeve 1 coaxially therewith. Screwed onto one end of the pin 2 by means of screw threads 4 is a mushroom-headed end- part 3. The other end of the pin 2, the outer end 5, is screw-threaded and carries a tensioning nut 6 and a locking nut 7 which is located radially outwards of the nut 6. The sleeve 1 has a central cylindrical part 8 onto which the inner race or like bearing-part 14 of a bearing 15 to be mounted on the shaft can be press fitted. The illustrated embodiment of the inventive arrangement further includes two wedge-shaped expander sleeves 9 and 10 which are caused to expand into engage- ment with a respective attachment lug 11 and 12 on the machine member, by tightening the nut 6. Disposed be¬ tween the expander sleeve 9 and the tensioning nut 6 is a turnable washer or plate 13 which has a smooth side facing towards the expander sleeve 9 in the manner illustrated. The shaft is locked to the machine member in the follow¬ ing manner. The end-part 3 is screwed onto the pin 2, whereafter the the expander sleeve 10 is fitted onto the sleeve 1 and the pin 2 is inserted through the axial bore of the sleeve 1. The expander sleeve 9 is then fitted onto the other end of the sleeve 1, whereafter the washer or plate 13 is fitted onto the pin 2 and the nut 6 is screwed onto the pin 2 and into abutment with the washer or plate 13. When tightening of the nut 6 is continued, the force generated thereby will cause the expander sleeves 9 and 10 to expand so as to be pressed into recesses 16 and 17 in respective lugs 11 and 12 and therewith lock the shaft to said lugs.

Claims: CLAIMS 1. An arrangement for locking a shaft or an axle to a machine member, said shaft being intended to carry a bearing on a central cylindrical part (8) thereof, said arrangement including first and second expander sleeves (9, 10) which have conical internal form and each of which is intended to be mounted on a respective end of corresponding configuration on the shaft, said expander sleeves (9, 10) functioning as annular wedges with the apex of the wedge facing towards the cylindrical part (8) of the shaft or axle and when tightened with the aid of tightening means (6) are caused to expand against the machine member and therewith lock the shaft thereto, c h a r a c t e r i s e d in that the shaft comprises an outer sleeve (1) which presents the conically shaped end-parts, and a pin (2) which is arranged coaxially with and within the sleeve (1) and one end of which has an outwardly curved, mushroom-headed end-part (3) whose radially inward surface is intended to abut an adjacent second expander sleeve, and the other end (5) of which pin (2) carries the fastener means (6) with which the first and second expander sleeves (9, 10) are caused to expand into clamping contact with the machine member. 2 An arrangement according to Claim l, c h a r a c¬ t e r i s e d in that a turnable washer or plate (13) is positioned between the fastener means (6) and the first expander sleeve (9); in that said other end (5) of the pin (2) is screw-threaded; and in that the fastener means (6) consists of a nut screwed onto said other end. 3. An arrangement according to Claim 1 or 2, c h a r a c t e r i s e d in that the mushroom-headed end-part (3) is a separate part which is screwed (4) onto the pin (2). 4. An arrangement according to Claim 2, c h a r a c¬ t e r i s e d by a lock nut (7) which is screwed onto the pin (2) outwardly of the tensioning nut (6).

Inventors: SVENSSON EVERT, SVENSSON ROGER, SVENSSON, EVERT, SVENSSON, ROGER
Applicants: SVENSKA EXPANDER AB
Application year: 1990
Main classification: F16C11
IPC codes: F16B3, F16B21, F16C11, F16D1