MXPA99007893A - Differential with fixing mechanism - Google Patents

Abstract

The present invention relates to a differential characterized in that it comprises: a housing defining a chamber and a pair of aligned openings: a pair of driving shafts having terminal segments that extend through the openings aligned in the housing and located inside the housing. chamber, a gear train for transferring the rotating force from the housing to the motor shaft, while allowing for differences in speed between them, the gear train being retained inside the chamber and including a pair of side gears fixed to the terminal segments of the drive shafts, and a button fastener assembly that includes a block spaced between the end segments of the drive shafts and having peripheral flanges extending outwardly from the opposing side surfaces to define open holding chambers within which They retain the terminal segments of the motor axes, also including the button clamp assembly a fastening shell mounted on the spacer block to cover the retaining chambers and enclose the end segments of the driving shafts, and a fastener to secure the fastening cap on the spaced block

Description

DIFFERENTIAL WITH AXLE CLAMP MECHANISM Field of the Invention The current invention relates to differentials for use in automotive drivelines and, more particularly, to a spacer assembly for a helical gear differential. BACKGROUND OF THE INVENTION Differentials of the type used in automotive control lines generally include a planetary gear train held within a differential housing to facilitate relative rotation (ie, differentiation in speeds) between a pair of driving axles. In helical gear differentials, the gear train typically includes helical side gears fixed to one end of the drive shafts that are interlocked with sets of helical pinion pairs inserted into gear pockets formed in the differential housing. Because the gear pockets are parallel to the rotational axis of the differential housing, the pinions rotate on axes that are parallel to the common axis of the drive shafts and the side gears. In response to the differentiation in speeds between the driving axes, the torsional moment transmitted through the interlocking coupling of the lateral gears and pinions generates pressure forces that are exerted by the components of the gears against the surface of the wall of the pockets of gears and other pressure surfaces inside the differential housing to frictionally limit such differentiation in speeds and the ratio of torsional moment between the driving axes. A problem associated with some of the conventional helical gear differentials is the axial separation of the drive shafts within the differential housing relative to the side gears. A related problem involves the conservation of an appropriate spatial relationship between the ends of the motor axes. More typically, C-mount slides are used to retain the ends of the drive shafts in relation to the side gears. In addition, it is known to install spacers (eg, dowels, blocks, pressure plates, etc.) in the differential housing between the terminal ends of the drive shafts. However, due to limited access to the gear train, such spacers can be difficult to install inside the differential housing. Examples of conventional arrangements of spacers and fasteners in helical differentials are shown in U.S. Patent Nos. 4,495,835, 4,51,221, 5,221,238, 5,554,018, 5,671,640.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a spacer assembly for use in a helical differential which is superior to conventional C-clamp devices and spacers, in terms of simplified function and assembly. According to a preferred embodiment of the present invention, a shaft spacer and fastener mechanism, hereinafter called a button clamp assembly, is installed between the ends of the shafts inside the differential housing of a differential assembly. The end of each shaft includes a button-type terminal cushion formed by an annular groove adapted to receive a C-fastener therein for locating and restricting a lateral gear between the differential housing and the shaft. The button fastener assembly includes a spacer block having a peripheral flange extending outwardly from its opposite side surfaces to define a pair of open retention chambers. The spacer block is disposed between the axes such that the button-type terminal cushions are located inside the retention chambers. The button fastener assembly also includes a fastening shell secured to the spacer block to enclose the open end of the retaining chambers and the end cushions. When installing the C-bracket in the slots, the end cushions are retained inside the retaining chambers of the spacer block and the C fasteners are laterally delimited - by the side gear and the button fastener assembly. In this way, the lateral space between the axes is maintained and the fasteners in C are prevented from disengaging. In addition, the button fastener assembly is free to rotate with respect to any of the axes and is easily installed through conventional windows. formed in the differential housing. Other areas of applicability of the current invention will become apparent from the detailed description below. However, it should be understood that the detailed description and specific examples, while indicating a preferred embodiment of the invention, are for illustrative purposes only, since various modifications and changes will become apparent to those skilled in the art, without departing of the spirit and scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood with reference to the detailed description and the accompanying drawings, in which: Fig. 1 is a perspective view of a differential assembly equipped with the button fastener assembly of the present invention; Fig. 2 is a terminal view of the differential assembly shown in Fig. 1; Fig. 3 is a sectional view taken generally along line 3-3 of Fig. 2, having removed the axes; Fig. 4 is a sectional view taken generally along line 4-4 of Fig. 2; Fig. 5 is a sectional view taken generally along line 5-5 of Fig. 2; Fig. 6 is a sectional view taken generally along line 6-6 of Fig. 5; Fig. 7 is a first perspective view of the spacer block associated with the button fastener assembly of the present invention; Fig. 8 is a second perspective view of the spacer block; Fig. 9 is an enlarged terminal view of the spacer block; FIG. 10 is a first perspective view of a fastening cap associated with the fastener assembly of the present invention; Fig. 11 is a second perspective view of the fastening cap; Fig. 12 is a first perspective view of the button fastener assembly; and Fig. 13 is a second perspective view of the button fastener assembly of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY Referring to Figs. 1-13, an axle retention mechanism for use with a differential assembly 10 will be described. The differential assembly 10 will be described in sufficient detail to represent the structure and function of the axle retention mechanism. In particular, the differential assembly 10 is of the helical parallel shaft type used in automotive control line applications. However, it will be understood that the shaft retention mechanism of the present invention is applicable for use in various differential assemblies 10 and, as such, the particular structure is illustrative only. The differential assembly 10 includes a housing assembly 12 defining an internal chamber 14. The housing assembly 12 includes a main drum 16 and an end cap 18 which is secured to a radial flange 20 of the drum 16 by means of a plurality of bolts. (not shown) installed in aligned mounting holes 22. As is known, a bevel or bevel gear may be held in the radial flange 20 in the housing assembly 12 to transfer the rotating force (i.e., torsional moment) to the same. The housing assembly 12 defines a pair of aligned axial openings 24 and 26 in communication with the chamber 14 and which are adapted to receive and support in a manner that allows their movement, the terminal segments of a pair of driving shafts, called the present axes 28a. and 28b. The terminal segment of the axes 28a, 28b includes a corresponding annular groove 30a, 30b separating a button-type terminal pad 32a, 32b from an externally ribbed segment 34a, 34b. The terminal pads 32a, 32b have a corresponding peripheral circular surface 36a, 36b, an outer surface 38a, 38b, and an inner surface 40a, 40b. The outer diameter of the end cushions 32a, 32b is shown slightly smaller than the outer diameter of the spline segment 34a, 34b on the axes 28a, 28b. As will be explained, a button fastening assembly 42 is installed between the end cushions 32a, 32b to maintain axial spacing between shafts 28a and 28b and prevent axial separation thereof. The differential assembly 10 includes a planetary gear train that operates to transfer the torsional moment from the housing assembly 12 to the axes 28a, 28b in a manner that facilitates the difference in speeds between them. The helical gear train is mounted in the chamber 14 and includes a pair of side gears 44a44b having internal ribs 46a, 46b interlaced with external ribs 34a, 34b on the corresponding axis 28a, 28b. In addition, the side gears 44a, 44b include axial hubs 45a, 45b retained in corresponding annular plugs formed in the drum 16 and terminal shell 18 of the housing assembly 12 and annular chambers 47a, 47b. C-retaining springs, or C-clips 48a, 48b, are retained in aligned slots 30a, 30b and chambers 47a, 47b to axially position and constrain the side gears 44a, 44b between the end wall surfaces of the housing assembly 12 and the terminal pads 32a, 32b of the axes 28a, 28b. The helical gear train also includes a series of first sprockets 50 inserted in pockets 52 formed in raised segments of the hub 54 of the drum 16, and a series of second sprockets 56 inserted in pockets 58 also formed in segments of the hub 54 of the drum 16. The pockets 52 and 58 are formed in pairs such that they communicate with each other and with the camera 14. In addition, the pockets 52 and 58 are aligned such that they are substantially parallel to the rotational axis of the axes 28a, 28b. When assembled, the first pinions 50 engage with the side gear 44a while the second pinions 56 engage with the side gear 44b. In addition, the pairs are arranged such that one of the first sprockets 50 is also engaged with one of the second sprockets 56. Windows 60 are formed in the drum 16 between the hub segments 54 and are provided to allow access to the gear train in. of the chamber 14. In accordance with the present invention, the button fastener assembly 42 is provided to maintain the side gears 44a, 44b and shafts 28a, 28b in an axially spaced relation relative to each other, while avoiding uncoupling inopportune of the fasteners at C 481, 48b of the slots 30a, 30b. The button fastener assembly 42 includes a spacer block 62 and a fastening shell 64 which, when assembled, can be joined by means of a threaded fastener 66. As is best seen in Figs. 7 and 8, the spacer block 62 has a pair of laterally spaced flat surfaces 68a, 68b. Extending outward from the surface 68a, 68a are peripheral flanges 70a, 70b which, together with the flat surfaces 68a, 68b, define horseshoe-shaped retention chambers 72a, 72b. Holding chambers 72a, 72b are configured such that the corresponding external surfaces 38a, 38b of the end cushions 32a, 32b are adapted to be aligned in proximity to the corresponding surfaces 68a, 68b of the spacer block 62 while the peripheral surfaces 36a, 36b of the terminal pads 32a, 32b are aligned in proximity to the inner edge surfaces 74a, 74b of the flanges 70a, 70b. A threaded hole 76 is shown extending between a flat mounting surface 78 and an outer surface 80 of the spacer block 62. By inserting the C-fasteners 48a, 48b into the slots 30a, 30b and the chambers 47a, 47b, the spacer block traverses one of the windows 60 in the drum 16 such that the open end of the flanges 70a, 70b fits the peripheral surfaces 36a, 36b of the end cushions 32a, 32b. Once the terminal pads 32a, 32b are located in the holding chambers 72a, 72b, a surface 82 of the fastening shell 64 is aligned with the mounting surface 80 of the spacer block 62 such that its opening 84 aligns with the threaded hole 76. In this position, as best shown in Figs. 12 and 13, the ears 88 extending from the opposite edges of the surface 82 on the fastening cap 64 cover the open end of the holding chambers 70a, 70b. Subsequently, the fastener 66 is screwed into the fastening shell 64 and inserted into the spacer block 62 to form the button fastener assembly 42. The push fastener assembly 42 allows for the installation of the C fasteners 48a, 48b, keeping the axes 28a, 28b separate and at the same time keeping the C-fasteners 48a, 48b in place. Once installed, the button fastener assembly 42 is free to rotate with respect to any of the axes 28a, 28b and the housing assembly 12. When the vehicle is entering a curve, the outer rim acts to force the spacer block 62. against the opposite lateral gear 44a, 44b. The button fastener assembly 42 maintains the proper spatial relationship between the axes 28a, 28b and the side gears 44a, 44b under curve conditions. As such, the button fastener assembly 42 comprises, in essence, a retention method for C-bracket shafts, without limiting their rotation. The invention being described, it will be apparent that it can carry many variations. Such variations should not be considered deviations from the spirit and scope of the invention, and all these modifications, as will be apparent to those skilled in the art, should be included within the scope of the following claims.

Claims (2)

1. CLAIMS 1.- A differential characterized in that it comprises: a housing defining a chamber and a pair of aligned openings; a pair of driving axes having terminal segments that extend through the openings aligned in the housing and located inside the chamber; a gear train for transferring the rotating force from the housing to the motor shaft, at the same time allowing differences in speed between them, the gear train being retained inside the chamber and including a pair of lateral gears fixed to the terminal segments of the motor axes; and a button fastener assembly that includes a spacer block between the end segments of the drive shafts and having peripheral flanges extending outwardly from the opposing side surfaces to define open holding chambers within which the end segments of the drive shafts are retained. motor shafts, also including the button clamp assembly, a fastening shell mounted on the spacer block to cover the retaining chambers and enclose the end segments of the driving shafts, and a fastener for securing the fastening shell on the spacer block.
2. 2. The differential according to claim 1, characterized in that each end segment of the motor shafts includes an annular groove and a terminal cushion adapted to be retained inside the chamber, and also comprising a fastener clip adapted for retention in the annular groove and against the corresponding lateral gear to locate and axially restrict the side gear on the end segment of the drive shaft between the clip and the housing. 3. - The differential according to claim 2 characterized in that the clip clip is adapted to be retained in an annular chamber formed in the side gear and that is aligned with the annular groove in the motor shaft such that the clip fastener is delimited laterally by the side gear and the push button assembly. 4. The differential according to claim 2 characterized in that the terminal cushion has an external surface adapted to be located in proximity to the lateral surface of the spacer block and a peripheral surface adapted to be located in proximity to an inner edge surface of the peripheral tab. 5. The differential according to claim 2, characterized in that the fixing cap has a surface adapted to be located in proximity to a mounting surface in the spacer block such that an ear that extends from the surface of the fastening cap the open end of the holding chamber. 6. - The differential according to claim 1 characterized in that the spacer block has a hole and the fastening cap has an aperture alignable with the hole, the fastener extending through the opening and into the hole to hold the cap of Fixation in the spacer block. 1 . - The differential according to claim 1 characterized in that the gear train also includes pinions mounted to allow rotation in pockets of gears formed in the housing and communicating with the camera, including the pinions a first pinion interlaced with one of the side gears and a second pinion interlocked with the other of the side gears and the first pinion. 8. The differential according to claim 7, characterized in that the gear pockets are parallel to the rotating axis of the driving axes. 9. - A differential assembly characterized in that it comprises: a differential housing defining a chamber and a pair of aligned openings in communication with the chamber; a pair of drive shafts extending through the openings in the differential housing and having terminal segments located inside the chamber; a pair of lateral gears arranged in the chamber and fixed to the terminal segments of the driving axes; sets of pairs of pinions mounted to allow their rotation inside the differential housing and in interlocking coupling with each other and with one of the lateral gears; and a button fastener assembly including a spacer block having a body portion disposed between the end segments of the drive shafts and retaining tabs extending from opposite sides of the body portion to partially surround the end segments of the shafts motors, also including the button fastener assembly, a fastening shell mounted on the body portion and extending beyond an edge of the body portion to define a cap flange cooperating with the retaining flanges to completely enclose the end segments and to prevent the push-button assembly from moving laterally relative to the driving axles. 10. - The differential assembly according to claim 9 characterized in that the body portion of the spacer block includes a threaded hole for receiving a threaded fastener that is inserted through an opening in the fastening cap to hold the fastening cap on the block spacer 11. The differential assembly according to claim 9, characterized in that the button fastener assembly is free to rotate relative to the driving axes and the differential housing. 12. The differential assembly according to claim 9, characterized in that the body portion and the retention flanges of the spacer block are generally configured in U to define a pair of open retention chambers inside of which the terminal segments of the spacer are located. the motor axes. 13. The differential assembly according to claim 9, characterized in that the retaining flanges define a pair of open retention chambers inside of which the terminal segments of the driving shafts are retained, and wherein each of the terminal segments of the drive shafts includes an annular groove and a terminal cushion adapted to be retained within the retaining chamber, and which also comprises a fastener clip adapted to be retained in the annular groove and against the corresponding lateral gear for axial positioning and restraint. lateral gear in the terminal segment of the motor shaft between the clip and the housing. 14. The differential assembly according to claim 13, characterized in that the clip is adapted to be retained in an annular chamber formed in the side gear and which is aligned with the annular groove in the motor shaft such that the clip is delimited laterally by the side gear and the button clamp assembly. 15. A differential assembly for the provision of torsional moment from a drive shaft to a pair of driving axes, characterized in that it comprises: a differential housing adapted to be rotationally driven by the propeller shaft, the housing defining a chamber having openings for axes in its opposite ends; a pair of lateral gears disposed inside the chamber, the lateral gears being mounted, so as not to allow their rotation, in the terminal segments of the driving shafts extending through the shaft openings; a pair of interlocking differential gears mounted to allow their rotation inside gear pockets formed in the differential housing, the pinions having a longitudinal axis parallel to the axis of the lateral gears, each pinion being interlaced with one of the lateral gears; and a button fastener assembly including a spacer block having a body portion disposed between the end segments of the drive shafts and a peripheral flange extending from opposite sides of the body portion enclosing an outer surface of the segments terminals of the motor axes, where the button clamp assembly is free to rotate in relation to the drive shafts and housing. 16. The differential assembly according to claim 15 characterized in that the button fastener assembly also includes a fastening shell connected to the spacer block, the fastening shell cooperating with the peripheral flange to secure the fastener assembly between the end segments of the motor axes. 17. The differential assembly according to claim 15, characterized in that the peripheral flanges define a pair of open retention chambers inside of which the terminal segments of the driving shafts are retained, and wherein each of the terminal segments of the Motor shafts include an annular groove and a terminal cushion adapted to be retained inside the holding chamber, and also comprising a fastener clip adapted for retention within the annular groove and against one of the corresponding side gears for axially locating and restraining the side gear on the end segment of the drive shaft between the fastener clip and the housing. 18. The differential assembly according to claim 17, characterized in that the fastening clip is adapted to be retained inside an annular chamber formed in the lateral gear and which is aligned with the annular groove in the motor shaft such that the fastening clip is delimited by the lateral gear and the push button assembly. EXCERPT OF THE INVENTION A shaft spacer and fastener mechanism, called a button clamp assembly, is installed between the ends of the shafts within the differential housing of a differential assembly. The end of each shaft includes a button-type terminal cushion formed by an annular groove which is adapted to receive a C-clamp to axially position and constrain a lateral gear between the differential housing and the shaft. The button fastener assembly includes a spacer block having a peripheral flange extending outwardly from its opposite side surfaces to define a pair of open retention chambers. The spacer block is disposed between the axes such that the button-type terminal cushions are located inside the retention chambers. The button fastener assembly also includes a fastening shell fastened to the spacer block to cover the open end of the retaining chambers and enclose the end cushions. When installing the C-bracket in the slots, the end cushions are retained inside the retaining chambers of the spacer block and the C-clips are laterally delimited by the side gear and button fastener assembly.