FR2616495A1 - UNIVERSAL JOINT - Google Patents

Abstract

The invention relates to universal joints. It relates to a universal joint in which two half-shafts 2a, 2b each formed of two half-elements, are arranged around a spherical member 5. The contact surfaces of the half-shafts 2a, 2b with the spherical member 5 are parts of cylindrical surface of the same diameter as the spherical member 5. In addition, the parts delimiting these surfaces have a frustoconical shape centered on the center of the spherical member. Application to universal joints intended to transmit low to medium torques.

Description

2.616495

  The present invention relates to a universal joint and more specifically to such a joint comprising two half-shafts and a spherical member placed between the two half-shafts and intended to connect them so that at least one of them is movable.

  A universal joint usually has a first

  first half-shaft, a second half-shaft and a cross or

  a spherical member connecting the half-shafts via

  stirrups belonging to these. However, these conventional universal joints are invariably made up of a very large number of elements and consequently

  manufacture or assembly is inconvenient. In particular

  when establishing a universal joint of quali-

  high, each organ should be performed with a precision

  sion and the assembly of the organs thus produced is

  difficult. Consequently, such a universal joint of quali-

  The high price tends to be expensive.

  - In view of the prior art, the inventor has already suggested an improved universal joint, in the

  Japanese Utility Model Published Application No. 51-59744.

  In the case of this universal joint however, as the spherical housing faces of the parts forming the stirrups are delimited in concave form, along a spherical face of the spherical member, the stirrup parts

  should be removed so that they house the spherical organ

America.

  As a result, when stirrups and half

  trees are formed in one piece, they must be

  made of a material having sufficient elasticity.

  However, when using a plastic or the like as an elastic material for example, the formed universal joint can be used for the transmission of low torques but not for the transmission of high torques. Accordingly, as shown for example in Figure 4 of the aforementioned document, the parts forming the stirrups and the half-shafts are made of a metallic material, independently of each other, and, after arrangement of the spherical member in the parts of stirrups, these and the half-shafts are fixedly connected by fastening devices such as screws. However, the above-mentioned construction and method can be improved so that the mounting is easy.

and the cost is reduced.

  Consequently, the subject of the invention is an improved universal joint which does not have the disadvantages of the prior art and which can be manufactured and

mounted with a low cost.

  For this purpose, a universal joint according to the invention comprises a first and a second half-shaft comprising two stirrup-shaped parts and a spherical member intended to be placed between the first and second halves so that they are connected to each other. to one another by being movable relative to each other. More precisely, this universal joint is characterized in the following manner. The first and the

  second half-tree-are each made up of two-half

  separate elements together forming the pair of stirrup parts. Seats are formed in facing faces of the stirrup parts and have a frustoconical shape so that each cone has a virtual vertex of angle substantially equal to 90, the virtual vertices of the cones being substantially in contact or confused. In addition, curved faces are formed in the surfaces facing the seats. Each of the

  these curved faces have a central axis of transverse direction

  dirty to half-trees and is a peripheral part of a

  virtual cylinder with the same diameter as the spherical

  which is supported by the curved faces so that it

can turn.

  The operation and results are now described.

  given by such a construction.

  In this construction, it is not necessary

  that a connecting device, for example by punch-

  is used for connecting the respective parts of the stirrups of the first and second half-shaft to the spherical member, since the first and second half-shafts can be easily connected and mounted by proper determination of their angle of

  cooperation. In addition, as the first and second half

  shaft and spherical member all have a relatively simple configuration or construction, these bodies can be

  made in an inexpensive way. Moreover, as the

  spherical shaft and at least one of the half-shafts are sup-

  carried by the curved faces so that they can turn,

  by linear contact at four peripheral faces

  external lines arranged on two transverse axes

  intersecting perpendicular to the center of the spherical

  the transmission of couples between the two half-lives

  shafts can be achieved regularly, even with relatively high tolerances, and this universal joint is suitable enough for applications

  important forces, in the presence of

  because there is no connection by punching, matting or mounting of another kind of spherical

and the stirrup.

  In addition, the half-shafts are constituted by the combination of two separate half-elements, the half-shafts can be easily manufactured in series in any way - conventional, for example by molding, by working with the press

(forging) or the like.

  In addition, in a variant of the invention, in the universal joint described above, one of the first and second half-shafts is integral with a spherical member,

  replacing the independent spherical organ previously described

  the other half-shaft forms a seat, in opposite faces of the two stirrup parts, these faces having a

  frustoconical shape so that each cone has a vertex

  angle of substantially 90, the virtual vertices of the cones being substantially in contact or confused. In addition, curved faces are formed in the surfaces facing the seats. Each of these curved faces has a central axis of direction transverse to the half-shafts and

  is formed by a peripheral part of a virgin cylinder

  the same diameter as the spherical member which is supported between the curved faces so that it can rotate. The previous construction has the following advantages. First, as one of the half-trees is united

  of the spherical organ that replaces the spherical organ

  during the construction described above, this

  construction forms a more robust structure of

  well suited to the transmission of high torques,

  given the smallest number of connecting elements

  Dement. Then, this construction allows an additional reduction of cost and a greater efficiency by reduction of the operations of manufacture and assembly of the

universal joint.

  Other features and advantages of the invention

  will be better understood by reading the description

  which follows, with reference to the accompanying drawings in which: Figure 1 is a section through a transverse plane

  representing a universal joint according to a method of

  preferred embodiment of the invention; Figure 2 is a section along the line II-II of Figure 1; Figure 3 is a side elevation of a first half-shaft of the universal joint of Figure 1; Figure 4 is a section along the line IV-IV of Figure 3; Figure 5 is a plan view. following the arrows V of Figure 3; Figure 6 is a plan view illustrating the mounting operations of the universal joint according to the invention; Figure 7 is an exploded side elevation in partial section showing the first half-shaft (or the second half-shaft); Figures 8, 9 and 10 are sections showing various devices for connecting the half-elements; Figures 11 to 16 are respectively a longitudinal section and cross sections showing various devices for connecting the half-elements formed to the press and shown in Figure 11; Figure 17 is a longitudinal section of a universal joint according to another advantageous embodiment of the invention; Figure 18 is a section along the line II-II of Figure 17; Fig. 19 is a section showing another embodiment of the invention; Figure 20 is a section on the line II-II of Figure 19; and

  FIG. 21 is a section showing the connection

  of a half-shaft comprising a spherical member

  is integral and another half-shaft.

  We first refer to Figure 1; a single joint

  versel A according to the invention comprises a first half-shaft 2a and a second half-shaft 2b, each having a pair of

  parts of stirrup 1, seats 3 having a truncated shape

  nique and made in the faces opposite the parts 1 stirrup, curved faces 4 formed in the facing faces of the seats 3, and a spherical member 5 supported

  between the curved faces 4 so that it can rotate.

  The seats 3 of frustoconical shape, as represented in FIG. 3, are made in such a way that each cone has a virtual vertex a having an angle of 90 substantially, the virtual vertices having cones being substantially

contact, that is to say, confused.

  In addition, the two curved faces 4 formed at the

  upper face of the seats 3 have a central axis

  substantially perpendicular to the shafts 2a, 2b and these

  faces are formed along a peripheral face portion

  a virtual cylinder b of the same diameter as the

spherical 5.

  The assembly of the universal joint A having the aforementioned construction is described with reference to FIG. 6. After the spherical member 5 has been introduced between the curved faces 4 of the stirrup parts of the first half-shaft 2a, the second half -tree 2b is slid laterally, its axis being perpendicular to the first half-shaft 2a, the curved faces 4 of the second half-shaft 2b then being slid on the spherical member 5. Then, the half-shafts 2a, 2b are spaced so that they are aligned. Accordingly, the spherical member 5 is supported by the curved faces 4 of the first member 2a and the second member 2b so that it can rotate in linear contact with the four outer peripheral faces, along two axes

  intersecting perpendicularly the center of the spherical

  In addition, since the spherical member 5 is placed between them, the two half-shafts 2a, 2b can not separate from each other. When these half-shafts 2a, 2b are connected while being aligned as shown in FIG. 2, as the inclined lateral faces of the frustoconical seats 3 of the half-shafts 2a, 2b are in mutually linear contact, the half-shafts 2a, 2b do not can not move in the direction perpendicular to their axes,

  so that a couple can be transmitted reliably.

  Referring now to Figure 7 (which does not represent

  only one of the half-trees); the half-shafts 2a, 2b consist of two separate half-elements 2a1 and 2a2,

  forming the respective stirrup parts 1. The half

  respective elements 2al and 2a2 can be made

  by welding as shown in Figure 8, or by a fastening device such as bolts 6 shown in Figure 9, or they can be connected to each other by arranging around them an outer collar 16 as shown in Fig. 10. Reference numeral 15 in Fig. 8 denotes flanged portions formed by welding.

  The half-shafts 2a, 2b, constituted by the combination

  its half-elements 2a1 and 2a2 can be easily manufactured by molding or the like. In addition, since the half-shafts 2a, 2b are identical, their production in

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  big series is even easier. If the half-trees must

  can be used in low torque applications,

  the elements can be mass-produced to one.

  extremely low cost, for example by pressing a sheet of metal. In this case, one more

  wide variety of devices can be used for

  interconnection of half-elements 2al and 2a2. For example, as shown in Fig. 12, protruding portions 7 may be formed at the edges of the half-members 2a1 and 2a2, and these members may be connected at these weld-projecting portions. As shown in FIG. 13, the elements can be connected at projecting portions 8 by means of bolts 9. In addition, as shown in FIG. 14, one edge of the elements can be connected by matting and the other edge can be connected by a bolt 12. Obviously, both edges can be connected by matting. In FIG. 15, the half-elements 2a1 and 2a2 are connected by arrangement of a collar

  external 13 around them. Moreover, in the arrangement

  16, the half-elements are arranged one above the other on an outer peripheral face

  an inner collar 14 which, at its peripheral face

  dull, has grooves or grooves 14a, the various elements being connected by welding. The arrangement of Figure 16 is convenient because the half-elements can be connected by splines 14a to an external splined shaft.

(not shown)

  The curved faces 4 are formed along a portion of the peripheral face of the virtual cylinder b, having the same diameter as the spherical member 5. In this case, two projecting parts for example may be formed at the lower ends of the cylinder virtual b so that they support the spherical member 5 at its center and prevent the passage of the spherical member over the projecting portions. This arrangement is advantageous because

  the positioning of the spherical member 5 during its

  troduction is facilitated, so that the assembly of the seal

  is facilitated and the manufacturing yield is increased.

  In addition, as shown in FIGS. 17 to 20, various reinforcing members can be formed on the

half-shafts 2a, 2b.

  Thus, in the embodiments shown in Figures 17 and 18, ribs 17 are formed axially on the half-shafts 2a, 2b, the outer faces of the respective stirrup portions 1 of the half-shafts 2a, 2b. These ribs 17 are formed from the anterior edges of the respective stirrup portions 1 to the vicinity of their base. These ribs 17 reinforce the parts of the necks of the bases of the stirrup parts 1 and thus contribute to the overall reinforcement of the universal joint. In this case, the configuration of the ribs 17 may be advantageously modified according to the intended use of the universal joint A. For example, in place of the preceding ribs that leave. from the front edges of the stirrups 1 towards the proximity of the necks, the ribs can be formed only to the outer faces

stirrup collar 1.

  In addition, in the embodiments of FIGS. 19 and 10, reinforcing rings 10 are mounted on the thin outer surfaces of the neck portions of the stirrup portions 1 of the respective half-shafts 2a, 2b, the reinforcing rings 10 covering the parts thin, so that

  the thin parts covered by these rings 10 have practically

  the same thickness as the cylindrical parts of

  respective half-trees. This arrangement, despite its simplicity

  cited, gives sufficient strength to the joint.

  It is possible, for fixing the reinforcing ring 10 on the half-shaft, to form on the ring, on the half-shaft or on both, a locking groove intended to cooperate with a key attached to the half shaft , to the ring or both, or with an independent key intended to be introduced from the outside of the seal. It is also possible to fix by welding parts of

  contact of the ring and the half-shaft.

  The reinforcing ring 10 must have a thickness

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  such that the thin portion 21 may have at least

  the same thickness as the cylindrical portion 20 of the half-shaft when the ring 10 is mounted on the thin portion 21. In addition, the reinforcing ring 10 must be of sufficient length to cover the outer surface of the thin portion. , but it is not necessary that it join the end of the cylindrical part of the half (end opposite to that to which the organ

spherical 5 is introduced).

  In addition, if the half-shafts (half-members) or reinforcing members are formed of an injection-molded resin, the universal joint can still be manufactured at a lower cost due to the high manufacturing efficiency.

  given by the injection molding process.

  In addition, the half-shafts (half-elements) or reinforcing members may be formed of a material

  produced by an injection molding process of a material

  - raiau powder or metal powder. This method of molding by injection of a metal powder is described

briefly in the sequel.

  Initially, a metal powder, for example stainless steel, is well mixed with a suitable binder so that the powder particles are covered with the binder. Then, the mixture is processed in a granulation device to form granules that can be easily introduced into an injection molding device. This material in the form of granules is heated and then melted by injection into a mold having a predetermined shape. After this molded material has been heated again so that the binder contained therein is removed, the material is subjected to a sintering operation. In this sintering, the material has a physical shrinkage of 30%. Then, this shrinkage material is formed into a finished product. This shrinkage material has a high mechanical strength because it has a very compact structure and is suitable for the formation of a very robust half-shaft or reinforcement member,

  with a higher yield than that of the manufacturing

  other processes such as molding or

to the press.

  Furthermore, the powder material used in the above process may be, in place of a stainless steel powder, a ceramic powder, a plastic powder or the like, depending on the intended application of the universal joint. In these cases too, it is possible to manufacture the organs with high efficiency without loss of material, so that the universal joint can be manufactured

at an even lower cost.

  In the construction shown in Figure 21, one of the half-shafts 2a is integrally formed with a spherical member 5 'on which the other half-shaft 2b is mounted, so that a universal joint A is formed. In this case, as the curved face 4 of the other half-shaft 2b is in contact with the spherical member 5 'of the half-shaft 2a, the half-shaft 2b can rotate relative to the spherical member. The above construction has advantages because the universal joint is more robust and is better suited to applications requiring high torques, being

  given the reduced number of connections ..

  This construction is also advantageous because the

  mounting ration can be further facilitated, the joint

  can be assembled by a single mounting operation.

  As a result, the manufacturing yield of the universal joint

  versel can still be improved.

  This half-shaft, integral with the spherical-shaped member

  In the construction shown in FIG. 21j, it can easily be carried out by the aforementioned injection molding method (especially in the case of the use of a resin-based material) or by the injection molding process. 'a metal powder (especially in

  the case of the use of a metallic material).

  Of course, various modifications can be made by those skilled in the art to the universal joints which have just been described as examples only.

  limiting without departing from the scope of the invention.

Claims (12)

  A universal joint, of the type comprising: a first and a second half (2a, 2b), each having a pair of stirrup parts (1), and a spherical member (5) disposed between the first and second   the second half shaft (2a, 2b) so that it connects the half   trees by allowing the movement of one of them at least,   characterized in that the first and second half   shaft (2a, 2b) are constituted by two separate half-elements   res (2al, 2a2) forming together the pair of stirrup parts (1), in that seats (3) having a frustoconical shape are arranged in opposite faces of the stirrup parts (1), each cone having a virtual vertex (a) making an angle of substantially 90, the virtual vertices (a) of the facing cones (3) being   practically in contact, in that the seats (3) delimit   curved faces (4) arranged opposite, and in this   that the seats (3) have a central axis of trans-   to the half-shafts and are formed by a portion of a peripheral surface of a virtual cylinder (b) having the same diameter as the spherical member (5) which is supported so that it can rotate between the curved faces (4).   2. Universal joint according to claim 1, characterized   characterized in that the half-elements (2a1, 2a2) constituting the first and second half-shafts (2a, 2b) are formed by a forging device.   3. Universal joint according to claim 1, characterized   characterized in that the half-elements (2a1, 2a2) constituting the first and second half-shafts (2a, 2b) are formed by a stamped metal sheet.   4. Universal joint according to claim 1, characterized   characterized in that the half-elements (2a1, 2a2) constituting the first and second half-shafts (2a, 2b) are formed by   a method of injection molding a resin.   5. Universal joint according to claim 1, characterized   characterized in that the half-elements (2a1, 2a2) constituting the first and second half-shafts (2a, 2b) are formed of a metallic material shaped by a method of   injection molding of a powder material.   A universal joint comprising: first and second half shafts (2a, 2b) each having a pair of stirrup portions (1), and a spherical member (5 ') positioned between the first and second half shafts (2a, 2b) and connecting them so that at least one of the first and second half-shafts (2a, 2b) is movable, characterized in that one of the first and second half-shafts (2a, 2b) is formed in one piece with   the spherical member (5 '), the other half-shaft (2a, 2b) forms   in facing faces of a pair of stirrup parts (1), seats (3) having a frustoconical shape such that each cone has a virtual vertex (a) at an angle of substantially 90, the virtual vertices (a) cones - being substantially in contact, in that the seats (3) delimit curved faces (4) in facing faces, and in that the seats (3) have a central axis of direction transverse to the last and are formed by a portion of a peripheral face of a virtual cylinder (b) having the same diameter as the spherical member (5 ') which is supported so that it can rotate between the curved faces (4).   7. Universal joint according to claim 6, characterized   in that the first and second half-shafts (2a,   2b) are formed by an injection molding process.   8. Universal joint according to claim 6, characterized   characterized in that the first and second half-shafts (2a, 2b) are made of a metal material shaped by a process of injection molding a powder material.   9. Universal joint according to any one of the   1 to 6, characterized in that a reinforcing   cement (10) is attached to an outer peripheral surface of a thin portion (21) of the first half-shaft (2a) and the   second half-shaft (2b), the reinforcing member (10)   covering at least part of the outer peripheral surface.   10. Universal joint according to claim 9, characterized   characterized in that the reinforcing member (10) comprises a reinforcing ring having a thickness such that the thin portion (21) can have substantially at least the same   thickness that the cylindrical portion (20) of the half   respective shafts (2a, 2b) when the ring (10) is on the thin part (21).   11. Universal joint according to claim 9, characterized   characterized in that the reinforcing member (10) is a   rib formed axially on the first and second half   shaft (2a, 2b) to an outer surface.   12. Universal joint according to claim 11,   characterized in that the rib starts from the anterior edges of the first and second half-shafts (2a, 2b) and joins the   near the thin part (21). - -