Abstract: A control apparatus of an automated manual transmission includes an input shaft provided with a plurality of drive gears, an output shaft provided with a plurality of driven gears engaged with the drive gears, and a reverse idler gear engaging with gears for backward movement respectively provided at the input and output sides when a backward moving stage is selected, as a mechanism for backward moving. Further, there is provided with a bypass clutch capable of selectively transmitting or shutting a power of the input shaft to the output shaft. When the backward moving stage is selected (S1), the bypass clutch is engaged (S3) so as to stop a rotation of the input shaft (S4), and thereafter, the reverse idler gear and the backward moving gears are engaged with each other (S5). Thus, a shift operation to a reverse mode can be securely and smoothly executed for a short time.

Abstract: A transmission having one or more clutches and brakes wherein only one clutch or brake need be engaged to connect the input to the output is equipped with a two-step actuator valve arrangement in which two valves, arranged in series, must be opened before any clutch or brake is engaged to power the output shaft. A single first-step actuator valve is arranged in series with a plurality of second-step actuator valves. Each of the second-step valves controls a clutch or brake.

Abstract: A PTO clutch of an agricultural vehicle connects an input driveline to an output driveline for coupling to an attached implement. A method and system for controlling the PTO clutch includes sensors for sensing rotational speeds on both sides of the clutch. Clutch slip is determined from the sensed speeds. A controller receives an actual slip signal and a desired slip signal and controls pressure in the clutch to maintain a constant desired clutch slip in order to avoid overload conditions. The torque transmitted by the clutch is determined as a function of the slip in the clutch and the clutch pressure, and a signal representing this torque is displayed to an operator.

Abstract: A method for controlling hydraulic pressure of an automatic transmission for a vehicle is provided. The automatic transmission has a clutch element engaged by a solenoid pressure to perform speed change. The solenoid pressure is generated by a solenoid that is driven by a solenoid drive current. The method calculates a required clutch engagement pressure and a required solenoid pressure corresponding to the required clutch engagement pressure based on a relationship between the clutch engagement pressure and the solenoid pressure. The method outputs a required solenoid drive current corresponding to the required solenoid pressure based on a relationship between the solenoid pressure and the solenoid drive current. The solenoid outputs the solenoid pressure corresponding to the required solenoid drive current.

Abstract: The engageable and disengageable friction clutch between the prime mover and the gearbox in the power train of a motor vehicle can be adjusted by an electric motor against the opposition of at least one resilient element by applying rest current from a source to an electric motor which opposes the bias of the resilient element in response to detection, by a sensor, that the bias of such resilient element upon a displaceable clutch actuating member exceeds the force then being exerted by the clutch. The application of rest current to the motor normally takes place when the vehicle is started and/or subsequent to shifting of the gearbox into a different gear. The thus actuated motor can prevent a worm wheel gearing or an analogous motor-operated component from partially disengaging the clutch when the disengagement is undesirable or harmful.

Abstract: The present invention provides a method and apparatus for controlling the pressure of an actuating fluid flowing through an inching clutch. The invention includes the steps of determining an actual pressure of the actuating fluid, establishing an inching pressure threshold, comparing the actual pressure with the threshold, and controlling the actual pressure in response to the comparison. In one embodiment, the pressure is controlled using a first control algorithm in response to the fluid pressure being less than an inching threshold, and using a second control algorithm in response to the pressure being greater than or equal to the inching threshold.

Abstract: A transmission having one or more clutches and brakes wherein only one clutch or brake need be engaged to connect the input to the output is equipped with a two-step actuator valve arrangement in which two valves, arranged in series, must be opened before any clutch or brake is engaged to power the output shaft. A single first-step actuator valve is arranged in series with a plurality of second-step actuator valves. Each of the second-step valves controls a clutch or brake.

Abstract: The automatic servo-mechanism for sequential gearbox and clutch, which is fitted or which can be fitted to a motorised vehicle, comprises: a sequential gearbox, a hydraulic circuit (1) and an actuator (11) that controls the clutch, which actuator is actuated by a solenoid valve (10), characterized therein that it consists of: a selector (15) that regulates the analog electric signal that controls the solenoid valve (10), a microswitch (16) on the lever that actuates the clutch mechanically; the hydraulic circuit also contains at least one check valve (6) downstream of the pump (3); at least one pneumatic-hydraulic accumulator (7), connected downstream of the aforementioned check valve; the aforementioned proportional solenoid valve (10) that regulates the pressure in the controlled section (33) this is connected to the aforementioned actuator (11) according to the analog signal received.

Abstract: A vehicle driving system having a clutch actuator and gear shifting device that use motors is provided. A clutch is disengaged and engaged and gear shifting is conducted at high speeds. The clutch actuator drives the clutch and includes a motion converting mechanism and two motors. The motion converting mechanism is a mechanism for converting rotary motion to linear motion and for applying an operating force to the clutch. The two motors are for applying a rotating force to the motion converting mechanism. The gear shifting automatically shifts gears by driving a transmission rack of a transmission and includes a ball screw mechanism and two motors. The ball screw mechanism is a mechanism for converting rotary motion to linear motion and for applying an operating force to the transmission. The two motors are for applying a rotating force to the ball screw mechanism.

Abstract: An electro-hydraulic control mechanism provides controlled engagement pressure for both a torque converter clutch and a shifting torque transmitting mechanism. The control mechanism include a TCC regulator valve that establishes the engagement pressure for the torque converter clutch and a TTM regulator valve that controls the engagement pressure for the torque transmitting mechanisms. An electronically-controlled variable bleed solenoid controls the output pressure level of both of the regulator valves. A control valve is employed to multiplex the output of the regulator valves and to ensure that the torque transmitting mechanism remains engaged during the engagement of the torque converter clutch. The control valve also ensure that the output pressure of the TTM regulator valve is communicated with a manual control valve in the event of an unexpected discontinuance of electrical power.

Abstract: A control system is utilized for the starting and running-down of a PTO shaft on an agricultural vehicle, such as a tractor. The hydraulically actuated clutch, as well as the other parts and sub-assemblies connected with the clutch as part of the drive, attain a maximum service life under all conditions of use. The control system, both in normal operating mode and also in management operating mode, protects the cardan shaft against destruction through too great an angle of flexion. Finally, in the management mode of operation, the control system prevents the occurrence of a loss of time, which would reduce the effective time of use of the tractor with the tool in question, and renders impossible a stalling of the engine when starting the PTO shaft through too early ground contact of the tool, in which the PTO shaft is not yet turning.

Abstract: A hydraulic actuation system for an automated transmission system including, a hydraulic clutch actuator (22) for controlling engagement of a clutch (14), a gear engagement actuator (114,115) for controlling engagement of a gear, said gear engagement actuator (114,115) being in the form of a double acting ram having first and second working chambers (118,119) acting on opposite sides of a piston (116,117), a main control valve (120), the main control valve (120) selectively connecting the clutch actuator (22) and/or the gear engagement actuator (114,115) to an accumulator (275) or to a reservoir (278); a gear engagement control valve (144,146) selectively connecting the first and second working chambers (118,119) of the gear engagement actuator (114,115) to the main control valve (120) or to the reservoir (278); an electrically driven pump (223) being provided to charge the accumulator, the pressure of fluid supplied by the pump being controlled by variation of the current driving the pump (223).

Abstract: A system reduces the amount of work exerted by an ATV operator to change transmission gears. The system includes a foot lever assembly with a mechanical portion, such as a mechanical linkage, attached to an automated portion, such as an electrical switch. When the ATV operator applies a predetermined amount of force to the foot lever assembly, a clutch assembly and a gear box are actuated in a single motion, assisted by the automated portion of the foot lever assembly. Thus, the operator is able to exert less work in order to change the gears.

Abstract: A hydraulic actuation system for an automated transmission system including an active clutch includes, a hydraulic clutch actuator for controlling engagement of the active clutch, a gear engagement actuator for controlling engagement of a gear, a hydraulic accumulator, a hydraulic fluid reservoir, a main control valve for selectively connecting the hydraulic clutch actuator and the gear engagement actuator to the accumulator or to the reservoir and an isolation valve for isolating the gear engagement actuator from the main control valve, when the clutch actuator is connected to the accumulator, the clutch actuator causing the clutch to engage when connected to the accumulator and causing the clutch to disengage when connected to the reservoir. Two such hydraulic actuation systems may be connected in parallel to control the clutches of a twin clutch transmission system, allowing the twin clutch transmission system to be driven in a restricted emergency mode, using only one clutch.

Abstract: A method is provided for controlling a PTO clutch of a transmission subject to a varying inertial load. The method includes providing a signal to a pressure control valve selectively engaged with the PTO clutch configured to engage a drive source of the transmission with an implement. The signal to the pressure control valve is modulated based on a single predetermined profile.

Abstract: Within the scope of the method for acceleration of the torque breakdown of clutches in automatic transmissions, the follow-up of the hydraulic pressure and therewith the torque breakdown are accelerated by an over-compensation in the control.

Abstract: A walk behind self-propelled crawler has a travel ready lever mounted to one of the left and right handlebars and adapted to be gripped by a human operator to place the electric motors in an operative condition, and a clutch control pushbutton switch disposed on the control board at a position close to the other handlebar, the clutch control pushbutton switch being adapted to be manually operated to actuate the electromagnetic clutch.

Abstract: A control system for a selective clutch that prevents interference with automatic engagement/disengagement of a friction clutch (2) when manual engagement/disengagement is selected at the time of starting a vehicle. The selective clutch includes an autoclutch device that automatically disengages and engages the clutch (2) using an actuator (10) under the control of a controller (6, 9). The selective clutch also includes a manual clutch device that allows engagement and disengagement of the clutch based on depressing of a clutch pedal (11). The clutch disengagement and engagement by the autoclutch device is prohibited, or the prohibition is canceled, based on a vehicle velocity (28), gear speed (23) of a gear box (3), and clutch pedal depression (16).

Abstract: A torque transfer system, particularly an automated shift transmission of a motor vehicle, has a movable shifter element that is subject to a position-dependent force. The gear positions of the transmission correspond to minima of potential energy of the position-dependent force, so that the movable element will have a tendency to fall into the nearest one of the shift positions. To perform a gear shift, the movable shifter element is moved into the vicinity of the targeted gear position by means of a control device directing a shift actuator. When the movable shifter element has stopped moving within a given tolerance band of the targeted position, the control device generates a stall-releasing signal, e.g., a series of pulses of alternating polarity to overcome a holding force or holding torque of the movable element, so that the latter will seek a position of minimum potential energy and thus move towards the targeted gear-shift position.

Abstract: Disclosed is a shift control method comprising the steps of determining if an input shift signal is a power-on upshift signal; determining if driving conditions satisfy power-on upshift learn conditions if the input shift signal is a power-on upshift signal; performing power-on upshift control if power-on upshift learn conditions are satisfied; learning an initial fill time and completing shifting; determining if shifting is completed; determining if run-up occurred during the shift operation if shifting is completed; determining if interlocking occurred if run-up did not occur; determining, if interlocking occurred, if the interlocking is above a predetermined level; and learning a fill time if the interlocking is above the predetermined level.

Abstract: The present invention provides a clutch connection method which controls the disconnection/connection of a wet friction clutch on the basis of a duty pulse outputted from an electronic control unit. When the clutch is connected, the electronic control unit initially outputs a start duty (Dst) for largely connecting the clutch as far as the vicinity of a torque point, and, thereafter, outputs, at prescribed time intervals (&Dgr;t), a gradual connection duty (Dk) for gradually connecting the clutch, and determines a gradual connection duty value on the basis of a clutch input/output side revolution difference &Dgr;N. Since the clutch is gradually connected while monitoring the clutch connection state, variations between connection times and connection shock, resulting from individual clutch differences or the like, can be eliminated, whereby it is possible to achieve a stable feel.

Abstract: A method and a device for actuating a motor vehicle clutch device (4). A control device (12) automatically influence the frictional power of the clutch device (4) in accordance with predetermined criteria (19) by varying the continuously variable ratio of a vehicle transmission (2).

Abstract: The present invention provides a shift control valve that controls the supply of engagement control hydraulic pressure to a drive friction engagement element and a reverse friction engagement element, having first and second main pressure oil lines (such as oil lines 151, 152, and 155) provided in parallel between a manual valve 58 and an oil line 100 (main pressure supply source) linked to a main regulator valve 50, oil lines 121, 122, and 156 that connect the manual valve 58 to a LOW clutch 11, and oil lines 130, 131, 132, and 133 that connect the manual valve 58 to a reverse clutch 14, and a first linear solenoid valve 86 (linear A) that allows the main pressure to be set as desired being provided to at least one of the first and second main pressure oil lines.

Abstract: The invention relates to a transmission system with a shift mechanism for controlling the transmission system, a control device for controlling a transmission system with a shift mechanism, a method for controlling such a transmission system or shift mechanism, as well as an application for the transmission system.

Abstract: A first clutch circuit for an automatic transmission in a hybrid drive vehicle comprises an apply line extending from a manual valve to a clutch, with a check ball disposed in the apply line operable to move out of the apply line upon upstream fluid pressure, and an exhaust line extending from the apply line, downstream of the check ball, to an exhaust valve. A driver-triggered valve actuating means operates to close the exhaust valve when the driver selects drive with a driver shift lever and to open the exhaust valve when the driver shifts out of drive thereby releasing the clutch.

Abstract: In a power transmission apparatus for a vehicle having a hydraulic pressure type clutch capable of switching to transmit and cut power between a crankshaft of an engine and driving wheels and a clutch control valve for controlling hydraulic pressure provided to the clutch, the operational characteristic of the hydraulic pressure clutch is made variable and an adjuster mechanism for compensating for a wear amount of clutch plates is dispensed with. A clutch control valve includes a valve housing having an input port connected to a hydraulic pump and an output port connected to a clutch. A spool is capable of switching to communicate and cut the input port and the output port and is slidably fitted in the valve housing. Furthermore, a linear solenoid is coaxially connected to the spool and is capable of controlling output hydraulic pressure from the output port to a value in accordance with input current of the linear solenoid.

Abstract: In a power transmission apparatus for a vehicle having a gear transmission capable of transmitting power from a crankshaft of an engine to driving wheels by selectively establishing a plurality of shift stages of gear trains and a clutch for cutting power transmission from the crankshaft to the gear transmission in operating to shift the power transmission, when the clutch is operated to cut or connect in cooperation with the shift operation of the gear transmission, shift operability is promoted while avoiding an increase in weight. A gear transmission is shifted by a first actuator and a clutch is driven by a second actuator which is independent of the first actuator.

Abstract: A hydraulic actuation system for an automated transmission system including an active clutch includes, a hydraulic clutch actuator for controlling engagement of the active clutch, a gear engagement actuator for controlling engagement of a gear, a hydraulic accumulator, a hydraulic fluid reservoir, a main control valve for selectively connecting the hydraulic clutch actuator and the gear engagement actuator to the accumulator or to the reservoir and an isolation valve for isolating the gear engagement actuator from the main control valve, when the clutch actuator is connected to the accumulator, the clutch actuator causing the clutch to engage when connected to the accumulator and causing the clutch to disengage when connected to the reservoir. Two such hydraulic actuation systems may be connected in parallel to control the clutches of a twin clutch transmission system, allowing the twin clutch transmission system to be driven in a restricted emergency mode, using only one clutch.

Abstract: A hydraulic actuation system for an automated transmission system including, a hydraulic clutch actuator (22) for controlling engagement of a clutch (14), a gear engagement actuator (114,115) for controlling engagement of a gear, said gear engagement actuator (114,115) being in the form of a double acting ram having first and second working chambers (118,119) acting on opposite sides of a piston (116,117), a main control valve (120), the main control valve (120) selectively connecting the clutch actuator (22) and/or the gear engagement actuator (114,115) to an accumulator (275) or to a reservoir (278); a gear engagement control valve (144,146) selectively connecting the first and second working chambers (118,119) of the gear engagement actuator (114,115) to the main control valve (120) or to the reservoir (278); an electrically driven pump (223) being provided to charge the accumulator, the pressure of fluid supplied by the pump being controlled by variation of-the current driving the pump (223).

Abstract: Within the scope of the method for acceleration of the torque breakdown of clutches in automatic transmissions, the follow-up of the hydraulic pressure and therewith the torque breakdown are accelerated by an over-compensation in the control.

Abstract: A clutch between the combustion engine and the manual multiple-gear-ratio transmission in the power train of a motor vehicle is disengaged or otherwise adjusted in response to a signal from a control unit which processes signals transmitted by sensors serving to monitor the positions and/or the extent of movements of one or more mobile components of the manual transmission. A signal to disengage or to otherwise adjust the clutch is generated when the monitored position(s) of and/or the magnitude(s) of force(s) acting upon one or more mobile components indicate that the operator of the motor vehicle intends to shift the transmission into or from a selected gear ratio.

Abstract: An automatic transmission for a vehicle comprises a torque converter TC equipped with a lock-up clutch 4. This automatic transmission further comprises FIRST˜FOURTH speed clutches 31˜34 for a shift control executing a shift from an off-going speed ratio to an on-coming speed ratio by controlling the release of the hydraulic pressure from the off-going clutch and by controlling the supply of the hydraulic pressure to the on-coming clutch. A control system comprises first and second off-going pressure releasing valves 70 and 80, which release the hydraulic pressure from the off-going clutch during the shift, a lock-up control valve 40 and a lock-up timing valve 50, which control the engagement of the lock-up mechanism, and a linear solenoid valve 60, which supplies a control pressure to these valves and controls the operation of these valves.

Abstract: A pressure control apparatus and method are provided for controlling hydraulic clutches of a backward and forward drive switching device mounted in a transmission of a working vehicle such as a tractor. When a backward and forward drive switching shuttle lever is operated, a current supplied to an electromagnetic proportional valve is controlled to gradually increase the pressure for a hydraulic clutch corresponding to a direction of movement. When a propelling drive connecting and disconnecting clutch pedal is operated, the pressure for that hydraulic clutch is controlled through the electromagnetic proportion valve, based on a depressed position of the pedal. When the operator switches the shuttle lever from forward to backward or vice versa, a microcomputer causes the shuttle control current to rise at a point of time of start of a clutch engaging operation of the clutch pedal.

Abstract: A control system for a selective clutch that prevents interference with automatic engagement/disengagement of a friction clutch (2) when manual engagement/disengagement is selected at the time of starting a vehicle. The selective clutch includes an autoclutch device that automatically disengages and engages the clutch (2) using an actuator (10) under the control of a controller (6, 9). The selective clutch also includes a manual clutch device that allows engagement and disengagement of the clutch based on depressing of a clutch pedal (11). The clutch disengagement and engagement by the autoclutch device is prohibited, or the prohibition is canceled, based on a vehicle velocity (28), gear speed (23) of a gear box (3), and clutch pedal depression (16).

Abstract: An adaptive electronic transmission control for an automatic transmission having multiple-ratio gearing establishing plural torque flow paths between a torque input member and a driven member, the relative motion of the elements of the gearing being controlled by a friction torque establishing member and an overrunning coupling connection between two gear elements of the gearing. A ratio shift is achieved by establishing a driving connection between a selected gearing element and a torque delivery shaft. The shift is achieved by controlling the capacity of the friction element using a fluid pressure actuator. Shift quality is optimized by establishing a bias pressure on a friction element accumulator and by using a feedback control system to control the rate of change of transmission ratio during the shift.

Abstract: A system for controlling an automatic transmission of a vehicle, in which a pressure supply time to complete removal of the clutch-stroke play is determined based on the input shaft rotational speed. And a residual oil amount in the clutch is estimated and the time is corrected by the residual oil amount. The preparatory pressure to be supplied within the time is also determined based on the input shaft rotational speed and the ATF temperature. With this, it becomes possible to effect the clutch-stroke play removal within a less variant time and with a good response, thereby decreasing the shift shock effectively so as to improve the feeling of the vehicle occupant.

Abstract: An electronically controlled transmission has microprocessor and a clutch housing including an integrated solenoid controlled valve; the clutch housing including a valve track operatively receiving a valve element connected for operation by the integrated solenoid controlled valve; and a friction disc pack within the clutch housing having a piston actuator pressurized by fluid flow regulated by operation of the integrated solenoid controlled valve in response to electronic control signals from the microprocessor.

Abstract: A clutch control arrangement designed to prevent intentional starting of a vehicle while a clutch-stroke-position learning is being performed. The clutch control arrangement includes a mechanism for automatically disengaging and engaging a clutch. The vehicle has a manual transmission of which gear position (shift position) is changed as a driver operates a shift lever. The clutch control arrangement further includes a learning unit for learning a stroke position of the clutch, and a unit for interrupting the operation of the learning unit when the shift lever is operated toward a transmission gear engaged position during the clutch-stroke-position learning. Preferably, the automatic disengagement and engagement mechanism automatically disengages or engages the clutch depending upon a gear engaged condition of the manual transmission after interrupting the clutch-stroke-position learning.

Abstract: A clutch between the combustion engine and the manual multiple-gear-ratio transmission in the power train of a motor vehicle is disengaged or otherwise adjusted in response to a signal from a control unit which processes signals transmitted by sensors serving to monitor the positions and/or the extent of movements of one or more mobile components of the manual transmission. A signal to disengage or to otherwise adjust the clutch is generated when the monitored position(s) of and/or the magnitude(s) of force(s) acting upon one or more mobile components indicate that the operator of the motor vehicle intends to shift the transmission into or from a selected gear ratio.

Abstract: An apparatus for engaging and disengaging a clutch, which is applicable to a vehicle provided with a so-called semiautomatic clutch, and which can prevent occurrence of an engagement shock and jerky acceleration of a vehicle when an automatic engaging and disengaging mode and a manual engaging and disengaging mode are switched from one to the other. The apparatus includes a manual disconnection/connection device (2) for manually engaging and disengaging the clutch (1) by operating a clutch pedal (9), an automatic disconnection/connection device (3) for automatically engaging and disengaging the clutch (1) in accordance with a predetermined input signal, and switching control device (14) for switching between a manual engaging and disengaging mode and an automatic engaging and disengaging mode after the clutch (1) has been engaged. This post-engagement switching operation can prevent an engagement shock during the same operation.