Abstract: An improved automatic slack adjuster (10) for disc brakes is provided. The slack adjuster includes an elongated rod (16) threadably attached to a nut member (28), only one of which rod and nut member is rotatable relative to the housing (12) for slack adjustment purposes. A coil return spring (36) acts on spring seat washer (40) which bears on the nut member. The spring seat washer is rotationally fixed (42, 44) to the non-rotatable one of the rod and nut members to prevent wind-up of the coil return spring during a slack adjustment operation.

Abstract: An adjustable spring stop assembly (10) for a spring (S) received within a bore (B) is provided. The adjustable spring stop assembly comprises a washer member (12) and an adjustment member (14). The washer member is axially fixable within the bore and is provided with a centrally located aperture (16) and a plurality of radially extending, radially aligned slot pairs of different diametrical lengths (18--18, 20--20, 22--22, 24--24, and 26--26). The adjustment member is provided with a pair of axially extending and inwardly tapering ear portions (34) which may be received within any selected one of the slot pairs. The adjustment member is provided with a fitting (40) which is accessible from the exterior of the bore through the centrally located aperture in the washer member for incrementally selectively varying the separation (44) of a surface (32) on the adjustment member from the washer member.

Abstract: A combined shift control for a motor vehicle driveline comprising a change speed gear transmission and a two speed axle whereby, for instance, a five speed gear box with one reverse gear is effectively extended to provide a seven speed driveline with one reverse gear. The gear box includes three parallel shift rods (12, 13, 14) each carrying a respective selector block (15, 16, 17). The slot (18) of the fourth/fifth selector block (17) is deeper than usual so that the gear lever (21) can operate it in two different transverse positions. In the first position the gear lever (21) actuates the fourth and fifth gears, but in the second position, after overcoming a spring-loaded plunger (20) and operating two micro-switches (24) which serve to change the axle ratio to a higher value, the gear lever (21) effectively actuates two further driveline speeds (sixth/seventh) when selector block 17 is caused to move the shift rod 14 to engage fourth and fifth transmission gears again.

Abstract: An improved spider-anchor pin assembly (14) for a drum brake (10) is provided. The improved assembly includes a stamped sheet metal spider body (42) and a one-piece forged anchor pin piece (46) removably attached to the spider body by a plurality of threaded fasteners (82, 84). Preferably, the anchor pin piece is symetrical about a plane (P) extending normal to the axis of the anchor pin sections (94 and 96) and bisecting of the flange section (76) thereof.

Abstract: A fluid actuated shift bar housing assembly for a change gear transmission wherein the shift bars are biased to an axially centered neutral position by constant fluid pressure in a constantly pressurized chamber and are selectively axially moved to an axially displaced gear engaged position by selective pressurization of a selectively pressurized chamber. A detent mechanism is provided for retaining the shift bars in the displaced positions thereof, said detent providing a resistance to axial movement of the shift bars having a smaller axial magnitude than the axial centering bias of the constant fluid pressure.

Abstract: An anchor pin assembly (100) for a drum brake (10) is provided. The anchor pin assembly is mountable to a drum brake spider (14) provided with an anchor pin receiving bore (34). The assembly includes two anchor pin pieces (102 and 104) having inclined ramps (116 and 118) formed on the inner ends thereof, an expansion member (120) having mating ramps (122 and 124) formed thereon and a bolt (132) and nut (138) for applying an axially inward compressive force to the pieces to cause radially outward expansion of the expansion member.

Abstract: A sheet metal fastener (100) preferably for self retention to a panel (112) having a slotted aperture (130) therethrough and for receipt of an externally threaded fastener (136) is provided. The fastener defines a first (114) and second (126) thread engaging slot for engagement of externally threaded fasteners at two axially spaced external threads.

Abstract: A shift control mechanism for a change speed transmission, or a change speed transmission section, having selectively axially movable gears, the selective axial movement of which is effective to cause engagement and disengagement of the axially moved gear, is provided. The shift control mechanism is utilized for a four speed transmission, or transmission section, and comprises a first shift fork fixed to a first shift rail, a second shift fork fixed to a second shift rail and a third shift fork fixed to a third shift rail. The shift rails are independently axially movable, the first and second shift rails are concentrically received in a first bore of a housing, the third shift rail is received in the second bore of a housing, and positive interlock means are provided to prevent simultaneous displacement of any two or more of the shift rails.

Abstract: An axle wheel end assembly (10) is provided for vehicles having an onboard tire inflation system (12). The wheel end assembly includes a rotary seal assembly (68) defining an annular air chamber (70) which seal assembly is received in a relatively protected inboardly opening annular space (69) defined by an axle spindle surface (66) and an axially inboardly extending sleeve (62) of the hub (42). Open/close valve member (110) is located outboard of the hub flange (50) interposed the fluid connections between the annular air chamber (70) and the opening (120) to the tire rim (122) for isolating the interior of the tire rim from the inflation system for storage and/or steady state driving conditions.

Abstract: An improved control system for a change speed multiple drive axle assembly, such as a tandem axle assembly (10), having a lockable interaxle differential (35) is provided. The improved control system (306) permits engagement and disengagement of the interaxle differential lockup in either the high or low speed ranges of the tandem axle mechanisms (11 and 12) and includes means to sense actual and/or impending engagement (96) of the interaxle differential lockup (84) to prevent operator shifting of the axle shift selector switch (150).

Abstract: A simple change gear transmission utilizing an improved clutch structure and/or an improved idler structure to provide compounded countershafts is provided. The improved clutch structure involves the use of axially adjacent tube clutch members (76, 90) operated by side-by-side shift forks (86, 100) to selectively clutch one at a time four axially adjacent mainshaft gears (50, 52, 54, 56) to a mainshaft (18). Compound countershaft (16) comprising a forward portion (20) and a rearward portion (22) are provided for increasing the number and/or range of gear ratios. A combination tube clutch-idler shaft (108) is utilized to provide increased reduction to the rearward countershaft portion for first gear and reverse gear operation of the transmission.

Abstract: A shift actuator (10, 100, 200) for selectively shifting a shift member (12, 102) to one of at least two selectable operating positions is provided. The actuator includes a rotational member such as a cam (36) or scotch yoke flywheel (204) rotatably driven by a unidirectional rotational motor (26) to one of two or more selectable rotational positions, each of which rotational positions is effective to cause a single compression spring (56, 166) to urge an engagement member (64 and 66, 108) to axially move the shift member to one of the at least two selected positions.

Abstract: An improved mainshaft gear retainer assembly (66, 68) for a multiple countershaft (18, 18A) transmission (10) having at least one pair of floating mainshaft gears (44-46, 48-50) positioned axially close together in groups of two and clutchable to a mainshaft (40) one at a time by positive clutches (54, 56, 58) is provided. The improved mainshaft gear retainer assembly prevents axial movement of the two closely positioned gears and reacts the axial forces on a clutched one of the mainshaft gears toward and away from the other mainshaft gear to the mainshaft by means of thrust surfaces (46D--82B,82C--78C, 78D--74B, 74C--70, 94B--82C or 82B--84) which are all rotating, or tending to rotate, at the same speed as the clutched mainshaft gear and the mainshaft. The gear retainer comprises relatively simple components and allows easy assembly and disassembly of the mainshaft gears and gear retainers from the mainshaft.

Abstract: A single acting, clearance sensing slack adjuster for brakes is provided. The slack adjuster includes a displaceable brake actuation means (28), a rotatable driving member (74), and a rotatable driven member (82). A normally engaged positive clutch (64-66) provides a driving connection between the driven member and a rotatable adjustment member (50). The rotatable adjustment member is rotatable in a given direction to advance the brake friction member (32) to maintain the running clearance (38) within predetermined limits. The driving member is rotatable in the slack-decreasing direction of rotation thereof in response to greater than predetermined movement (102) of the brake actuation means. A force limiting coil clutch (80) couples the driving member to the driven member.

Abstract: A multiple substantially identical countershaft (16, 16A), simple change gear transmission (10) having two-piece (20, 20A, 22, 22A) countershafts is provided. The use of two-piece countershafts allows the countershafts to be supported by three bearings (72, 74 and 76) while not requiring greater than normal manufacturing accuracy of the transmission housing (H). A driving connection between the front and rear countershaft portions is utilized which will allow a degree of axial misalignment between the front and rear portions and which when connected assures proper circumferential alignment of the countershaft gears.

Abstract: A control (100) for positioning and locking the auxiliary transmission section (13) of a compound change gear transmission (11) in neutral is provided. The control includes a selector switch (132) for activating or deactivating the control and a monitoring device (42) for sensing if the main transmission section (12) is in neutral. The control, once activated, will retain the auxiliary transmission section in neutral until the selector switch is switched to a deactivated position (M) simultaneously with the main transmission section shifted to neutral.

Abstract: An improved, thin walled fastener for retaining studs, rods, or the like is provided. The fastener is of the push-on type comprising a one-piece, generally thin, stamped sheet metal resilient body defining a generally centrally located stud retaining aperture for receipt and retention of studs, rods or the like. The body is preferably generally frusto-conical or dome shaped in cross section. The fastener is formed by punching or shearing a hole in a blank and then forming a generally dome shaped impression in the blank, the impression being generally coaxial with the axis of the punched hole. The required transverse extensions of the body are minimized by the utilization of the relatively smooth continuous edge of the punched hole rather than the burred edge of a punched hole as the stud retaining edge of the fastener stud retaining aperture.

Abstract: An improved, blocked, change gear transmission utilizing at least one improved resilient jaw clutch assembly to selectively engage a selected gear to a shaft is provided. The improved jaw clutch assembly comprises two axially engageable jaw clutch members and a blocker mechanism to prevent engagement of the jaw clutch members until the jaw clutch members are rotating at a substantially synchronous speed. Preferably, one of the jaw clutch members carries axially and radially outwardly extending external clutch teeth designed for selective interengagement with axially and radially inwardly extending internal jaw clutch teeth carried by the other jaw clutch member. The improvement comprises providing a back-lash between the interengageable clutch teeth which is substantially greater than the back-lash normally utilized with similar clutch assemblies, said increased back-lash being in the range of five to fifteen times greater than normal back-lash and preferably about ten times greater than normal back-lash.

Abstract: An improved drum brake (10) is provided with an improved retaining spring (28) which passes over or close to the axis of the brake anchor structure (18). The improved retaining spring is a one-piece coil tension spring comprising a coil portion (46) and an attachment portion (50) extending axially from the opposite ends of the coil portion. Each attachment portion comprises a downwardly extending first section (52), an upwardly and outwardly extending second section (56), a downwardly extending third section (62) and an axially extending fourth section (64).

Abstract: A shiftable change speed gear system, particularly a transmission, having resilient shifting mechanisms for simplifying the transmission structure and the shifting thereof. The transmission is preferably provided with multiple countershafts having countershaft gears thereon disposed in meshing engagement with main shaft gears encircling the transmission main shaft, said main shaft gears being supported on and solely by the countershaft gears. The main shaft gears are axially movable relative to the main shaft by conventional means for effecting shifting of the transmission.