FR2689581A1 - Self-locking metal cap and plastic bearing. - Google Patents

Abstract

An assembly of a self-locking metal cap and plastic bearing cup which can be mounted at the end of a spider pin for attachment in the fork hole. 'a universal joint. According to the invention, a metal cap (24) has a circumferential side wall, an end wall and an open end and carries a bearing inside, resilient tabs (32) extending outwardly formed. with the side wall near the open end, and they can retain the bonnet in the bore after insertion and a monolithic plastic bearing cup (26) is fixedly mounted in the bonnet, the cup has a circumferential side wall, a end wall and an open end as well as a integral lip seal formed on the inner circumference of its side wall. The invention applies in particular to the steering mechanisms of vehicles.

Description

The present invention relates to support bowls for

  Universal joint fork pin ends and more specifically self-locking metal bearing cap assemblies and plastic bearings that immediately retain the cross in the forks of a universal joint. Universal joints are well-known devices used for the interconnection of two members or shafts adapted to rotate about respective non-aligned and / or angularly adjustable axes of rotation. Universal joints of this type are widely used in the steering mechanism of Typically, such universal joints comprise a spider which is formed by a central body portion having four circumferentially equally spaced and outwardly extending axes. The axes are coplanar and are arranged in opposed and axially aligned pairs which are arranged at right angle relative to each other A bowl is rotatably mounted on the end of each of the axes and each of the two opposite pairs of cuvettes is fixed in a fork The forks are respectively fixed

  to rotating members to form the universal joint connection.

  In general, the outer peripheral surface of the shaft and the inner wall of the associated bowl are spaced apart and a ring of needle bearings is disposed in this space. The needle bearings engage in rolling the wall or track and the axis to permit substantially frictionless rotation therebetween A separate seal consisting of a base of resilient elastomeric material is required to seal the opening that exists between the open end of the bowl and the axis.

  on the bowl at the time of assembly.

  When installing universal joints of this type, the following assembly method is frequently used. Two opposite axes on the spider are placed in the two holes which are formed in the arms of a fork. A bowl is inserted axially through one of the holes on the

  fork, the open end of the bowl receiving the end of the axis associated.

  A self-closing ring is then mounted in the bore, behind the closed end of the bowl, to prevent radial outward movement of the bowl, away from the axis. Another bowl is inserted through the bore into the bowl. the opposite arm of the fork and it is likewise fixed in position by a self-closing ring A fork is then mounted

  on the remaining pair of opposite axes in an identical manner.

  The present invention relates to a self-locking metal cap for a raceway which is adapted to receive a spider pin and to be secured in a fork bore of a universal joint assembly. A bearing cap metal having an open end and adapted to carry a raceway therein, has a number of outwardly extending resilient lugs or catch, which are integral with and spaced on the cap. metal inward from its open end These tabs lock immediately when inserted to hold the bowl in a fork hole after insertion This new construction eliminates the need for a self-closing ring, a throat associated with the ring

  self-closing and their assembly which is required.

  A plastic bearing is preferably mounted in the self-locking metal cap. The plastic bearing comprises a monolithic open end plastic cup and a material lip seal which is formed on the inner circumference of the open end of the tube. the bowl, which avoids the need for a separate seal At least one radial groove and at least one axial groove are formed in the inner surface of the bowl for lubrication purposes. The invention will be better understood and other purposes, features, details

  and benefits of it will become clearer during the description

  explanatory text which will follow with reference to the accompanying schematic drawings given solely by way of example and illustrating an embodiment of the invention and in which: FIG. 1 is a longitudinal elevational view, partially shown in longitudinal section, of the assembling one of the rotating members of a universal joint including self-locking metal cap and plastic bearing assemblies according to the present invention;

  FIG. 2 is an enlarged sectional view of a self-supporting metal cap;

  blocker and a track of Figure 1; and FIG. 3 is a plan view taken substantially along the line 3-3

of Figure 2.

  Referring now to the drawings, at 8 in FIG. 1 is generally illustrated a portion of an assembly of a universal joint comprising a fork 10 having two arms 12 and 14. A spider 16 is mounted between the arms 12 and 14 of the fork 10 by means of cup assembly 18 which are received in bores 19 of the arms 12 and 14 The spider 16 has a central body portion 20 having four outwardly extending axes which are circumferentially equally spaced 22 The shafts 22 are arranged in a single plane and at right angles to each other A bearing cup assembly 18 is rotatably mounted at the end of each of the pins 22 and each of the opposed pairs of cup assemblies 18 is attached to the fork 10 in the holes 19 which are formed in its arms 12, 14 Two forks 10 are fixed, each to one of a pair of rotating members (no

  shown) to form a universal joint connection.

  The assembly 18 of the bowl of the present invention, as can be seen more clearly in FIG. 2, consists of a self-locking metal cap 24 in which a bowl 26 of a suitable material rests, as will be described hereinafter. The metal cap 24 is provided with an open end and is adapted to receive a suitable support device for carrying the end of the shaft 22 as part of the assembly of a universal joint. The support ring may be of any suitable type, such as the needle roller ring which is typically used in universal joint bearing cups. Preferably, however, the support device is a plastic cup according to a another aspect of the present invention, as will be described in

detail below.

  The metal cap 24 is further provided with a number of outwardly extending resilient tabs 32 which are integral with the wall

  circumferential hat being formed for example by repelling them.

  The tabs 32 serve to securely retain the metal cap 24 in the bore 19 of the arms 12 or 14 of the fork when the cap 24 has been inserted through the bore 19 The tabs 32 are formed to slope towards

  the outside from the wall of the cap 24 and away from its open end.

  Thus, while the open end of the metal cap 24 is inserted into the associated bore, and as the outer diameter of the cap 24 is substantially equal to the diameter of the bore, the elastic tabs 32 are deformed to

  the interior to allow the insertion of the cap 24 through the bore 19.

  When the distal ends of the tabs 32 are completely passed through the bore 19, they return to their position extending outwardly so the distal ends of the tabs 32 engage the inner surface of the arm 12 or 14 of the fork The legs 32 thus allow immediate and automatic blocking of the assembly of the support bowl 18 during insertion into the bore 19

arm 12 or 14 of the fork.

  To ensure proper alignment of the metal cap 24 in the bore of an arm 12 or 14 of the fork, at least three tabs 32 must be formed in the metal cap. Preferably, four of these tabs 32 are formed, which are The lugs 32 may be of any suitable shape and formed by any suitable method and as previously indicated they are preferably formed pushing back the sections of the wall of the metal cap 24. In the preferred embodiment, the metal cap 24 retains a plastic cup 26 The cup 26 is in the form of a one-piece member having an open end and a lip seal 28 of material that is formed on the inner circumference of the open end The cup 26 is fixedly mounted in the metal cap 24 in any suitable manner, for example by pressure fitting or by means of Adhesive Suitable adhesives include epoxy resin adhesives The plastic cup 26 is provided with a chamfer edge 34 at the outer circumference of its closed end to facilitate assembly into the metal cap 24 The metal cap 24 reinforces and stiffens the plastic bowl 26, and holds it

  in good alignment with respect to the axis 22 and the arms 12 and 14 of the fork.

  The internal diameter of the bowl 26 is substantially equal to or slightly smaller than the outer diameter of the axis 22, so the bowl 26 can be mounted very precisely on the axis 22, for example, by a slight pressure fitting As it can be seen in FIG. 1, the lip seal coming from material 28 extends outwards, beyond the extreme surface of the bowl 26 and is adapted to come into sealing engagement with a shoulder 30 which is formed on the shaft 22 The seal 28 thus forms a seal to prevent the loss of lubricant from the interior of the bowl 26 as well as to prevent the introduction of foreign matter into the bowl 26 By integrally molding the lip seal 28 with the bowl 26, this eliminates the need for a separate seal member and the time and effort required for assembly. The plastic bearing cup 26 further has, on its inner surface, one or more elongated grooves which extend radially along the end wall and axially along the side wall of the bowl 26 to contain and dispense the lubricant at the interface between the bowl 26 and the axis 22 To this end, an axial groove 36 must be placed in order to communicate with an associated radial groove 38. In a preferred embodiment, as illustrated in FIG. the cut 26 is provided with three circumferentially spaced circumferential grooves 36, each in communication with an associated radial groove 38, the three grooves 38 radiating from an intersection approximately in the center

  from the closed end of the bowl 26.

  The plastic bowl may be formed of any suitable plastics. It has been found, by way of example, that 30% of glass-filled nylon 6, 6 and 30% of glass-filled nylon 4, 6 were good materials.

adapted to the bowl.

  When assembling the universal joints of the type comprising the self-locking metal cap and the assembly of the plastic support bowl 18 according to the present invention, two opposite axes 22 on the spider 16 are placed in the pair of bores which are formed in the arms 12 and 14 of a fork 10 The grooves 36 and 38 in the inner surface of the bowl 26 are filled with lubricant and the open end of the assembly 18 of the bowl is inserted through one end. holes 19 of the fork 10 with the open end of the bowl 26 receiving the end of the associated shaft 22, for example, by slight pressure adjustment When the tabs 32 formed in the cap 24 have passed completely through the piercing 19, they return to their outwardly extending position, so their distal end comes into engagement with the inner surface of the arm 14 of the fork The cap 24 thus allows an immediate and automatic blocking of the assembly 18 of the bowl during insertion into the bore 19 of the arm 14 of the fork A second assembly of a support bowl 18 is inserted through the bore in the opposite arm of the fork 10 identically and is fixed likewise in position.

Claims (9)

  A self-locking metal cap for fixing a bearing and adapted to carry the end of a spider pin in a fork piercing of a universal joint member, characterized in that it comprises: a cap metal (24) having an open end and which is adapted to carry a bearing therein; and a number of outwardly extending elastic tabs (32) integral with and disposed on the open end of said metal cap, said tabs adapted to retain said metal cap in a bore after insertion.   Metal cap according to claim 1, characterized in that each of the tabs (32) extends outwardly and further away from the open end of said metal cap (24), so that each of said tabs will deform towards the during insertion of the cap through a bore (19) formed in an arm (12, 14) of the fork to return to its extended position to   outside during a complete insertion of said hat.   Metal cap according to claim 1, characterized in that said cap (24) has a peripheral side wall and the tabs (32) comprise portions which are pushed outwardly of said side wall. Metal cap according to claim 1, characterized in that   has at least three legs (32).   Metal cap according to claim 4, characterized in that has four legs (32).   Metal hat according to any one of claims 4 or 5,   characterized in that the tabs (32) are substantially equally spaced   circumferentially on the hat.   Metal cap according to claim 1, characterized in that it further comprises a plastic bearing mounted in said metal cap (24). 8 Plastic bearing adapted to be mounted on the end of a spider pin and fixed in a fork hole of a universal joint member, characterized in that it comprises: a monolithic plastic bearing cup (26) having a circumferential side wall and an end wall and having an open end; a lip seal (28) of material which is formed on the inner circumference of the open end of the side wall of the bowl; at least one radially extending groove (38) which is formed in the inner surface of the end wall of said bowl; and at least one axially extending groove (36) formed in the   internal surface of the side wall of said bowl.   9 plastic bearing according to claim 8, characterized in that each groove (38) extending radially is placed in order to be in   communicating with an axially extending associated groove (36).   Plastic bearing according to claim 9, characterized in that it comprises at least three grooves (38) extending radially and at least three   grooves (36) extending axially.   Plastic bearing according to claim 9, characterized in that the radially extending grooves (38) are substantially equally spaced circumferentially.   12 Assembling a self-locking metal cap and a plastic support bowl mountable to the end of a spider shaft and secured in a fork hole of a joint member universal, characterized in that it comprises: a metal cap (24) having a circumferential side wall, an end wall and an open end, and adapted to carry a bearing therein; a number of outwardly extending resilient tabs (32) integral with said sidewall near the open end of said cap, said tabs adapted to retain said cap in the bore after insertion of said assembly; and a monolithic plastic bearing cup (26) securely fastened in said metal cap, said cup having a circumferential side wall, an end wall and an open end, a lip seal of material formed on the inner circumference of the wall side of said bowl at its open end, at least one radially extending groove formed in the inner surface of the end wall of the bowl and at least one axially extending groove formed in the inner surface of the side wall of the bowl.