AU685913B2

AU685913B2 - Improved puller tool

Info

Publication number: AU685913B2
Application number: AU17750/95A
Authority: AU
Inventors: Gary Rovere
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-05-31
Filing date: 1995-04-27
Publication date: 1998-01-29
Anticipated expiration: 2015-04-27
Also published as: AU1775095A

Description

1- P/oc4oil Regulation 3.2

AUSTRALIA

Patents Act 199 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

S

C

Name of Applicant: Actual Inventor: Address for service GARY ROVERE Gary Rovere in Australia: CARTER SMITH BEADLE :2 Railway Parade Camberwell Victoria 3124 Australia Invention Title: IMPROVED PULLER TOOL Details of Associated Provisional Application: PM5984 filed 31 May 1994 The folowing statement is a full description of this invention, including the best method of performing it known to us, -2- INTRODUCTION TO INVENTION This invention relates to puller tools and in particular to manual automotive or industrial tools for removing roller bearings and the like housed in blind recesses.

BACKGROUND TO INVENTION Ball and roller bearings comprise one or a plurality of independent turning elements separated by a number of balls or rollers. Such bearings find common application in numerous automotive, engineering and industrial situations where immersion lubrication is not practical and minimal friction is required in the turning element.

The mounting of ball and roller bearings requires engagement of the inner and outer races of a bearing on a shaft and within a housing respectively. The inner race must be a tight fit on the receiving shaft and the outer race must be a tight fit into the receiving housing in order to limit the relative motion to that between only the ball or rollers and the races.

In many situations, ball bearings are mounted in a blind housing where the bearing can only be accessed from one side. Accordingly, once the bearing is pressed home it is very difficult to remove as a blind housing prevents access to the rear of the bearing and requires that the bearing must be pulled out rather than pushed out.

Many automotive ball bearings fit into the above category where the bearing is fitted to a blind housing. Accordingly, many automotive bearings are very difficult to remove without necessitating a major dismantling of part of the vehicle or machine.

To date various puller devices have been developed to assist in removing 25 roller bearings, for example Australian Patent 556667 by Broden Installations Pty.

Ltd. Such tools require a detailed and time consuming "operation" to be performed on the in situ bearing in order to allow the tool to engage the bearing for removal.

Similarly Australian Patent 91277/91 discloses a tool for removing bearings which .i0* requires complex invasive interaction with the in situ bearing in order to facilitate removal. Furthermore, such devices require insertion of gripping means between the MAW:fP:#1558SPC 27Apntl99S I- I- -3inner and outer races where such areas of bearings are commonly shielded by dust and oil covers and seals. The operation of removing a bearing involv s considerable forces and the precarious nature of the engagement of such tools to the intermediate section of the bearing races may involve danger of damage to the bearing and housing and possible danger to the operator.

As an alternative to the use of such unsatisfactory devices, many operators rely on the use of improvised tools including hammers, punches etc., to prize the bearings out. Of course, the tight nature of a bearings location within a housing easily results in a bearing jamming if incorrectly removed or if any sideway twist results in inaccurate removal exasperating the task of removal.

OBJECT AND STATEMENT OF INVENTION One object of the invention is to provide an improved puller tool.

Accordingly, the invention provides a puller tool comprising a shaft having a first part capable of insertion through the inner aperture of a roller bearing or similar device when fitted in a housing and a retractable key fitted at or near the terminal end of said first part, wherein said retractable key may adopt a first position substantially within the confines of the outside diameter of said shaft first part allowing for said insertion through the inner aperture of a roller bearing and a second position exceeding the outside diameter of said shaft first part so as to provide for the subsequent engagement of said bearing by the co-operation of said and said bearing, and a drawing or pulling means fitted to a second part of said shaft which is adapted to pull said shaft and said engaged bearing from said housing.

The retractable key may be in the form of a centrifugal, gravity or spring activated key and the drawing means may be provided by the screw threading of the o 25 second part of the shaft and the provision of a nut or similar device in conjunction with a bridge mount shaped to abut the housing and provide the neceAsy leverage to support the puller.

The key is most preferably mounted substantially within the confines of the S".i terminal end of the first part of said shaft by way of a gudgeon pin posiPioned transverse to the axial direction of the shaft to provide a pivot for the key which is 27 A4 1995 -4shaped, dimensioned and positioned such that when the key adopts said first position, it is substantially aligned to the axial direction of the shaft and does not protrude beyond the transverse dimensions of the first part of the shaft but when the key adopts said second position, it is transversely aligned to said shaft and does protrude beyond the transverse dimensions of the irst part of said shaft, most preferably from either side of the shaft.

The key is preferably a semi-circular or half moon shaped disc of hardened steel, most preferably a woodruff type key.

The shaft may be provided with a means to prevent rotation of said shaft upon removal of a bearing, preferably in the form of a hexagonal configuration of the terminal end of said second part adapted to receive a spanner or socket.

DETAILED DESCRIPTION OF INVENTION_ A particularly preferred form of the invention will be described in greater detail by reference to the following figures in which: Figure 1 shows a side view of the puller tool.

Figure 2 shows a perspective view of the first part of the puller tool.

Figure 3 shows a bridge support.

Figure 4 shows the puller tool in a first position for insertion through an in situ bearing.

Figure 5 shows the puller tool in a second position inserted through and :....engaging an in situ bearing.

Figure 6 shows the puller tool extracting a bearing.

Referring firstly to Figure 1, the puller tools main component comprises a cylindrical shaft having a first part 1 of reduced diameter at one end of the tool.

3o, 25 The reduced diameter of this part of the tool allows the tool to be inserted into the aperture formed by the inner race of a ball or roller bearing which has been fitted into a housing. The terminal end of the first part of said shaft is provided with a axial slot 11 (visible in cross-section). The slot 11 accommodates a key 5 in the o form of a semicircular shaped woodruff type key of hardened steel. The key is mounted in a transverse pivot by way of a gudgeon pin 10 such that the key is free 27 Apil 1995 to rock from a first inclined position lying in substantially axial alignment with tlhe shaft to a second position lying in substantially transverse alignment with the shaft such that the ends of the key protrude from either side of the shaft 1. The first and second positions of the key are determined by the end face 14 and inclined face respectively of the axial slot 11 which provide stops for both the first and second positions of the key.

The first position provides for the key to lie substantially within the confines of the first part of the shaft 1 such that no part of the key 5 projects beyond the outside diameter of the first part of said shaft.

The second position (shown in Figure 2) provides for the key to lie in a position traverse to the shaft and thereby exceed the diameter of the first part of said shaft with the ends of said key projecting beyond the outside diameter of the first part of said shaft. The key is pivoted loosely in the slot to provide for the free movement of the key back and forth from the first and second position by the action of centrifugal force and/or gravity. The cylindrical shaft is provided with a second part 6 comprising the main body of the tool. The second part is a threaded shaft 12 co-axial with, and of greater diameter than, the first part of said shaft. The threading 12 provides the means of drawing or pulling the tool when used in conjunction with n bridge support and a suitable nut. The terminal end of the second S 20 part of the tool takes the form of a hexagonal head 13 adapted to receive a suitable spanner or wrench to steady the tool and prevent unwanted rotation during extraction.

"I Figure 2 shows a perspective view of the first part of the tool where the axial slot 11 is visible. The gudgeon pin 10 is positioned to allow the key 5 to adopt the 25 first position where the key is axially aligned and contained almost entirely within the slot such that no part of the key protrudes beyond the outside diameter of the :i first part of the tool and a second position where the key is transversely aligned and specifically projecting out from both sides of the first part of the tool.

S" Figure 3 shows the bridging support 7 having an aperture 16 of a suitable size to freely receive the fi3t and second parts of the shaft but provide a stop for the MAWPP:I58.SPC 27 As 1995 -6drawing nut 8. The bridging support provides the means of anchoring the tool against the housing and effecting the drawing of the bearing against the action of the nut 8. The size and shape of the bridging support shall be dictated by the specific housing worked on but the general purpose bridging shown in Figure 3 shall function in many circumstances.

Figures 4, 5 and 6 show the puller in use. To commence use, the key would be manually placed in the first position such that the first end of the tool 1, including the key 5, could be inserted through the aperture formed by the inner race of a ball bearing 2 via the bridge mount 7. Once the tool is inserted into the bearing with the first end and the key having traversed the inner race, the tool would be rapidly rotated so as to cause the key 5 to adopt the second position being transverse to the axial direction of the shaft by the action of centrifugal force, see Figure With the key 5 in the second position protruding beyond the diameter of the shaft 1, the tool can then be drawn back until the traversely positioned key is caused to abut the inner race of the ball bearing. Having abutted the inner race of the ball bearing 3, the tool then encounters the resistance of the bearing which is firmly located in a housing 4 or the like.

In order to draw or pull the tool and bearing from the housing, the second part of the shaft of the tool is provided with a threaded region 12. The threaded 20 region of the shaft is fitted with a suitably threaded nut 8. In conjunction with the second part of the shaft, a bridge mount 7 is adapted to co-operate with the nut 8 threaded onto the second part of the shaft 12 so as to provide an anchorage means for the puller tool. The bridge mount 7 is shaped to abut the housing 4 of said bearing so as to provide a means of levering the tools shaft 1 and engaged bearing 3 25 from the housing by winding up the nut 8 with a suitable spanner (see Figure 6).

The end of the second part of the shaft is provided with a hexagonal shaped head 13 to allow the shaft to be grasped and prevented from rotating against the winding action of the nut 8.

Once the bearing is removed from the housing, the whole tool will be released and the bearing can be disengaged from the puller tool.

MAWPi:#155.SPC 27A/ 199 -7- If the puller tool is required to be disengaged prior to full removal of the bearing, the inclined part of the axial slot 11 has been provided to additionally function as an access channel to allow a drift or other small diameter tool to be inserted through the shaft 1 in order to return the key from the traverse to the axial position thereby allowing the puller tool to be removed with the bearing still in situ.

From the foregoing the invention can be seen to provide a simple and reliable tool for extraction of roller or ball bearings or other types of devices inserted by a press fit into a housing, provided that such devices have a central aperture which can be accessed. The tool does not require invasive or destructive interaction with the bearing and provides an easy and reliable method of removing fitted bearings from housings.

6* 00 e o* MAW:PPfiiSSSSSPC 27 April 19S

Claims

8- The claims defining the invention are as follows: 1. A puller tool comprising a shaft having a first part capable of insertion through the inner aperture of a roller bearing or similar device when fitted in a housing and a single retractable key fitted at or near the terminal end of said first part, wherein said retractable key may adopt a first position substantially within the confines of the outside diameter of said shaft first part allowing for said insertion through the inner aperture of a roller bearing and a second position traversing and thereby exceeding the outside diameter of said shaft first part so as to provide for the subsequent engagement of said bearing by the co-operation of said key and said bearing, and a drawing or pulling means fitted to a second part of said shaft which is adapted to pull said shaft and said engaged bearing from said housing. 2. A puller tool according to claim 1 wherein said retractable key is adapted to move from said first position to said second position by the action of centrifugal force, gravity or a resilient means. 3. A puller tool according to claim 2 wherein said retractable key is activated by centrifugal force and pivotally mounted in an axial slot formed in the terminal end of the first part of said shaft by way of a gudgeon pin positioned transverse to the axial direction of said shaft across said slot. 4. A puller tool according to claim 3 wherein said retractable key is a shaped, dimensioned and positioned such that when the key adopts said first position, it is substantially aligned to the axial direction of said shaft and does not protrude beyond the transverse dimensions of the first part of said shaft and when the key adopts said second position, it is transversely aligned to said shaft and part thereof OO:. does protrude beyond the transverse dimensions of the first part of said shaft. 0 5. A puller tool according to claim 4 wherein said retractable key is a 0 semi-circular shaped woodruff type key having one curved edge and one straight 6 S. edge and being centrally pivoted in the axial slot of said shaft with the curved edge facing the terminal end of said shaft. Y°"L MAW'PP:#15585.SPC 23 OctOber 1997 -e e~pa~ ~pges~ -9- 6. A puller tool according to claim 5 wherein said axial slot has an end face and an inclined face adapted to abut the straight edge of said key and thereby determine the first and second positions of said key. 7. A puller tool according to any one of claims 1 to 6 wherein said second part of said shaft is provided with a screw thread and a nut adapted to co- operate with said screw thread to provide said drawing or pulling means whereby said puller tool and engaged bearing can be drawn or pulled against said housing. 8. A puller tool according to claim 7 wherein the terminal end of said second part of said shaft is provided with a hexagonal head.
9. A puller tool according to claim 7 incorporating a bridging support adapted to co-operate with said drawing means and said housing to facilitate the drawing of said puller tool against said housing. A puller tool according to any one of claims 1 to 9 substantially as hereinbefore described with particular reference to the examples. DATED: 27 April 1995 CARTER SMITH BEADLE Patent Attorneys for the Applicant: GARY ROVERE t o 1. MAW:PP lS58S.SPC 27 Apr 199 i I P~ll~ L l~l ABSTRACT A puller tool comprising a shaft having a first part 1 capable of insertion through the inner aperture of a roller bearing or similar device when fitted in a housing and a retractable key 5 fitted at or near the terminal end of said first prt, wherein said retractable key may adopt a first position substantially within the confines of the outside diameter of said shaft first part allowing for said insertion through the inner aperture of a roller bearing and a second position exceeding the outside diameter of said shaft first part so as to provide for the subsequent engagement of said bearing by the co-operation of said key and said bearing, and a drawing or pulling means 12 fitted to a second part 6 of said shaft which is adapted to pull said shaft and said engaged bearing from said housing. os *0 a a I~~b~a