Abstract: A compound transmission (10) comprising a main transmission section (12) connected in series with a range type multiple speed auxiliary section (14) having at least two selectable range type ratios, and a shift control unit (56) therefor, is provided. The shift control includes a resilient range interlock structure (178, 190) for inhibiting main section shifts from neutral during a range shift transient.

Abstract: A control system and method for a semi-automatic mechanical transmission system (10) is provided for sensing high resistance to vehicle forward movement and allowing engagement of a gear ratio lower than the lowest engageable ratio at substantially constant vehicle speed.

Abstract: A method and control for controlling an AMT system (10) having an operator actuated engine compression brake (17) is provided including sensing vehicle deceleration and monitoring throttle position (THL), vehicle brake actuation (BRK) and engine compression brake (ECB) actuation to select one of three (50, 52, 54) mutually exclusive vehicle deceleration downshift shift profiles.

Abstract: A control (220) for providing a dual pressure source (236) of pressurized fluid to a pressurized fluid operated shift actuator (30) for a mechanical change gear transmission (202) is provided.

Abstract: A control and control method for a semi-automatic mechanical transmission system (10) is provided for sensing operator request for a direct downshift into an optimum pull-away ratio and for automatically determining and engaging the optimum pull-away ratio.

Abstract: A control system and method for a semi-automatic mechanical transmission system (10) is provided for allowing operator request for a direct downshift into transmission neutral, under certain predefined conditioned, by a single movement of the shift lever (1).

Abstract: A self-diagnostic method for controlling an AMT system (10) is provided including sensing and identifying faulty input signals (THD, THPS and RTDS) from the throttle position sensor assembly (22) sensors (22A, 22B and 22C). If only a known one of the input signals is faulty, logic method of control (38) is modified to a logic method tolerant of the identified faulty input signal.

Abstract: A single shaft (106) shifting mechanism (100) for a change gear transmission (10) is provided. The shifting mechanism includes in-gear/neutral detent device (194, 196, 198) and stop and positioning devices (200, 202, 204,206) all of which are integral with the mechanism allowing a relatively simple block mechanism (102) to be utilized with standard remote and/or direct shift actuators.

Abstract: An improved control system and method for an automatic/semi-automatic transmission system (10) including an automatic change gear transmission (12) driven by a throttle (26) controlled engine (14) is provided. The control system includes a processing unit (42) for receiving inputs indicating at least throttle position (THL) and vehicle speed (OS) and for determining vehicle deceleration (dOS/dt) and for processing these inputs in accordance with a program or logic rules to determine the selected engaged gear ratio and for issuing command signals to a transmission shifting mechanism (34). The processing unit includes logic rules by which vehicle performance is maximized and the control will evaluate and allow and/or execute skip downshifts upon sensing conditions indicative of vehicle deceleration due to ascending a steep grade.

Abstract: A method for smoothing skip up-shifts in an automated mechanical transmission system (10) without requiring direct sensing of the rotational speed of the engine (14) is provided. The method involves delaying re-engagement of the master clutch (16) after engagement of a selected transmission ratio (E) during a skip up-shift by a period of time (T) directly proportional to the number (N) of ratios skipped and/or a function of the identity of the newly engaged ratio.

Abstract: An improved S-cam (100) for expanding internal shoe (20) drum brakes (10) is provided. The working surfaces (116) of the S-cam are provided at their ends with an extremely high rise/low mechanical advantage portion (122) providing a warning ramp to indicate to the operator that brake relining is required and to minimize the possibility of cam flip.

Abstract: A control for an extended range splitter type compound transmission (10) comprising a main transmission section (12) connected in series with a splitter type auxiliary transmission section (14) connected in series with an extended range section (15) is provided. The main section shift lever (72) has a first (1) and a second (1E) position for selection of low ratio (50). Selection of the second position (1E) will automatically cause the extended range section clutch (206) to be shifted to the speed reduction position thereof.

Abstract: An improved automatic clutch control system for controlling a vehicle master clutch (16) drivingly interposed a throttle controlled engine (14) and a change gear transmission (12) in an automatic/semi-automatic mechanical transmission system (AMT) is provided. A monitored clutch parameter (CPV) is compared to a reference value (IEPCPV) to determine the expected point of incipient engagement of the clutch. The reference value is periodically updated, to compensate for wear and the like.

Abstract: An electrically controlled, fluidly actuated X-Y type shifting mechanism (30) for cooperation with a mechanical change gear transmission shift bar housing assembly (10) normally controlled by a manual shift lever is provided. The mechanism (30) includes a housing (32) having a single pressurized fluid connection (52) and a single electrical connection assembly (50) which is mounted to a shift bar housing assembly normally receiving a shift lever lower. A shift finger (38) extends into the shift bar housing for cooperation with the shift rail (12, 14, 16) shift blocks (24, 26, 28) and is positioned by two transversely mounted, axially movable shafts (68, 110). Each of shafts is axially positioned in a selected one of three selectable axial position by piston/cylinder assemblies (46, 42) controlled by six three-way, two-position electrically operated valves (150, 152, 154, 156, 158, 160).

Abstract: A method for controlling an AMT System (10) is provided including sensing the presence of an existing or impending wheel lock-up condition and modifying the method for controlling the system to respond to said wheel lock-up condition in as safe a manner as possible. The method for controlling the AMT System (10) in response to sensing a wheel lock-up condition includes immediately releasing the clutch or coupling (14) and prohibiting the central processing unit (56) from issuing any transmission change gear command output signals.

Abstract: A control system and method for sensing and reacting conditions indicative of unacceptable slow CTIS response to selected pressure setting changes.

Abstract: A transmission shift yoke (3) (see FIG. 2) has to slide over the shift bar (1) and then be anchored accurately in the desired position by a fastener, i.e., set screw or bolt (8). The set screw must be locked to prevent its loss or more seriously its falling into machinery. A expansible snap ring (10) is arranged on a spotface (11) in a recess (12) in the bar; it is expanded by the tapered shank (14) of the fastener (8) and then snaps into a waist (19) of the fastener to prevent its being readily unscrewed more than half a turn or so. A really robust torque, however, on the head (9) by means of a spanner/wrench will forcibly expand the snap ring out of the waist (19) and over the widest part of the tapered shank (13).

Abstract: A clip to clip independently rotatable parts that must be axially held relative to each other, but not be constrained from sliding axially together. Each part (9, 10) has a bore and an internal annular groove (28) and the clip has transverse flanges (23, 24) that spring out and enter the grooves when the bores are aligned. The clip has a gap so that the cross-section can be changed considerably by gripping holes in the flanges with long-nosed pliars, or other gripping tool, that can enter the internal bores, address the clip to the grooves, and release the clip to enter the grooves. The tool is also used to remove the clip for dissembling the parts. Thus the parts, e.g. mainshaft gears, that have to be slide each way to engage respective dogs, can be replaced individually - in contrast to existing gear-pairs which tend to be unseparable without destruction of the clip (and usually of both gears).

Abstract: A transmission system (10) including a control display (2, 302) is provided. The control display comprised of three sections, a currently engaged gear ratio section (2'") a maximum permissible consecutive upshift indicating section (2') and a maximum permissible consecutive downshift indicating section (2"). The central processing unit (38) includes circuitry and logic rules to process input signals to determine the currently permissible gear ratios and will indicate said gear ratios, in the form of maximum permissible upshifts and downshifts, at said display. The central processing unit also includes circuitry and logic rules to sense the existence of a fault condition, to assign a predetermined code ("18") thereto and to issue command output signals to the display to cause the second and third sections to assume a fault condition indicating display and to cause said first section to display to assigned code.

Abstract: A compound transmission (14) comprising an input auxiliary section (18) and a main mechanical change gear transmission (20) is provided. The auxiliary section (18) utilizes friction clutch means (50) having a first and second selectable position for engaging a direct drive or reduction input ratio and a third disengaged position allowing the auxiliary section to provide the torque break function normally provided by a master clutch. Preferably, a positive clutch disconnect (66) is interposed between the friction clutch assembly and the main transmission section (20) to provide reduced main transmission section inertia to provide quicker, easier and and lower energy synchronization of the main transmission.