Abstract: A method of manufacturing a driving drum includes: molding a first cylindrical member including first large- and small-diameter parts, a diameter of an outer circumferential surface of the first small-diameter part being smaller than that of the first large-diameter part; molding a second cylindrical member having second large- and small-diameter parts, a diameter of an inner circumferential surface of the second large-diameter part corresponding to the diameter of the outer circumferential surface of the first small-diameter part, a diameter of an inner circumferential surface of the second small-diameter part corresponding to that of the first small-diameter part, and the diameter of the inner circumferential surface of the second small-diameter part being smaller than that of the second large-diameter part; and forming a first cam groove between the first and second small-diameter parts and forming a second cam groove between the first and second large-diameter parts.

Abstract: A power transmission mechanism equipped with a first shaft including a first double helical gear, a second shaft including a second double helical gear and a third double helical gear arranged in alignment with the second double helical gear in an axial direction, and a third shaft including a fourth double helical gear that meshes with the third double helical gear. The second double helical gear includes a pair of right and left tooth portions whose torsional directions are reverse to each other such that the left tooth portion and the right tooth portion are offset in phase from each other, and the third double helical gear includes a pair of right and left tooth portions whose torsional directions are reverse to each other such that the left tooth portion and the right tooth portion are identical in phase to each other.

Abstract: A method of manufacturing a driving drum includes: molding a first cylindrical member including first large- and small-diameter parts, a diameter of an outer circumferential surface of the first small-diameter part being smaller than that of the first large-diameter part; molding a second cylindrical member having second large- and small-diameter parts, a diameter of an inner circumferential surface of the second large-diameter part corresponding to the diameter of the outer circumferential surface of the first small-diameter part, a diameter of an inner circumferential surface of the second small-diameter part corresponding to that of the first small-diameter part, and the diameter of the inner circumferential surface of the second small-diameter part being smaller than that of the second large-diameter part; and forming a first cam groove between the first and second small-diameter parts and forming a second cam groove between the first and second large-diameter parts.

Abstract: With respect to a relation between an amount of axial displacement of a first bearing as well as an amount of axial displacement of a second bearing relative to an axial force generated at a meshing part between a first double-helical gear and a second double-helical gear, and an amount of axial displacement of the second bearing as well as an amount of axial displacement of a third bearing relative to an axial force generated at a meshing part between a third double-helical gear and a fourth double-helical gear, the second bearing is configured to have a smaller amount of axial displacement than that of at least one of the first bearing and the third bearing.

Abstract: There is provided a power transmission mechanism equipped with a first shaft including a first double helical gear, a second shaft including a second double helical gear and a third double helical gear arranged in alignment with the second double helical gear in an axial direction, and a third shaft including a fourth double helical gear that meshes with the third double helical gear. The second double helical gear includes a pair of right and left tooth portions whose torsional directions are reverse to each other such that the left tooth portion and the right tooth portion are offset in phase from each other, and the third double helical gear includes a pair of right and left tooth portions whose torsional directions are reverse to each other such that the left tooth portion and the right tooth portion are identical in phase to each other.

Abstract: With respect to a relation between an amount of axial displacement of a first bearing as well as an amount of axial displacement of a second bearing relative to an axial force generated at a meshing part between a first double-helical gear and a second double-helical gear, and an amount of axial displacement of the second bearing as well as an amount of axial displacement of a third bearing relative to an axial force generated at a meshing part between a third double-helical gear and a fourth double-helical gear, the second bearing is configured to have a smaller amount of axial displacement than that of at least one of the first bearing and the third bearing.

Abstract: A control device for a drive line of a vehicle, in which a drive line from a power source to drive wheel includes a wheel control for controlling the speed of the wheels, and a connection mechanism for increasing/decreasing a torque transmission capacity between the power source and the drive wheels. The control device includes a trouble detector for detecting that the wheel control is in a situation unable to control the speed of the wheels normally. A braking detector detects that a braking operation to brake the rotation of the wheels is executed. And, a torque interruption control reduces the torque transmission capacity by the connection mechanism, when it is detected by the trouble detector that the wheel control cannot control the speed of the wheels normally and when it is detected by the braking detector that the braking operation to brake the rotation of the wheels is executed.

Abstract: A vehicle drive apparatus has a pump that supplies operating fluid for performing speed shift control of a power transfer apparatus, and a driving motor that drives the pump. If it is determined that the power transfer apparatus is in a neutral state (N range), it is then determined whether the vehicle is running. If the vehicle is running, it is determined whether the operation speed of the driving motor has reached a speed that allows the pump to produce a predetermined fluid pressure. If that speed has not been reached, the motor operation speed is controlled to the speed that allows the pump to produce the predetermined fluid pressure. The vehicle drive apparatus secures a pressure and a flow of fluid when the power transfer apparatus is operated to the neutral state during the running of the vehicle.

Abstract: A vehicle drive apparatus has a pump that supplies operating fluid for performing speed shift control of a power transfer apparatus, and a driving motor that drives the pump. If it is determined that the power transfer apparatus is in a neutral state (N range), it is then determined whether the vehicle is running. If the vehicle is running, it is determined whether the operation speed of the driving motor has reached a speed that allows the pump to produce a predetermined fluid pressure. If that speed has not been reached, the motor operation speed is controlled to the speed that allows the pump to produce the predetermined fluid pressure. The vehicle drive apparatus secures a pressure and a flow of fluid when the power transfer apparatus is operated to the neutral state during the running of the vehicle.

Abstract: A hydraulic control system for an automatic transmission to establish a predetermined stage by applying a first frictional engagement element and releasing a second frictional engagement element, comprising: a first hydraulic servo for actuating the first frictional engagement element; a second hydraulic servo for actuating the second frictional engagement element; change-over means for switching the feed of an oil pressure to the first hydraulic servo; signal pressure generating means for generating a signal pressure; and a pressure regulator valve for regulating the pressure to be fed to the second hydraulic servo.

Abstract: A motor vehicle shift control apparatus wherein two hydraulically operated frictional coupling devices are simultaneously released and engaged, respectively, to effect a clutch-to-clutch shift of an automatic transmission, including an overshoot control device for compensating the hydraulic pressure of at least one of the coupling devices during the clutch-to-clutch shift such that the amount of engine speed overshoot is held within a predetermined range, and an inhibiting device for inhibiting an operation of the overshoot control device if a preventing device for preventing an excessive rise of the engine speed above an upper limit is expected to be activated, or if the preventing device is in operation. The inhibiting device may be replaced by a device for reducing the output of the engine if the engine speed is higher than a threshold not higher than the upper limit.

Abstract: A hydraulic control system for an automatic transmission includes a regulator valve in a hydraulic circuit for supplying pressure to a servo of a frictional engagement element. The regulator valve has an input port, an output port and a drain port. A valve member of the regulator valve includes a pressure receiving area fed with a feedback pressure from the portion of the hydraulic circuit between the regulator valve and the servo, and another pressure receiving area selectively fed with pressure from a signal pressure source. A further pressure receiving area, having a surface area different from the another pressure receiving area, is constantly fed pressure from the signal pressure source.

Abstract: A control system for an automatic transmission includes a first frictional engagement element and a second frictional engagement element; and a first hydraulic servo for controlling the application/release of the first frictional engagement element and a second hydraulic servo for controlling the application/release of the second frictional engagement element. A regulator valve regulates the oil pressure to the first hydraulic servo. A signal pressure is applied to the regulator valve to establish a predetermined gear stage by switching the applied/released states of the first frictional engagement element and the second frictional engagement element by feeding/releasing oil pressure to/from the first hydraulic servo and the second hydraulic servo.

Abstract: A shift control system for shifting an automatic transmission from a predetermined gear stage to another by draining an oil pressure from predetermined frictional engagement element to release the same frictional engagement element and by feeding the oil pressure to another frictional engagement element to engage the same frictional engagement element while controlling the drain oil pressure of the frictional engagement element to be released and the engaging oil pressure to the frictional engagement element to be engaged. The shift control system includes an engine racing detector for detecting the racing of the engine while the transmission is being shifted in a clutch-to-clutch manner, and a hydraulic control circuit for controlling at least one of the drain oil pressure and the engaging oil pressure, on the basis of the degree of racing of the engine, as detected by the engine racing detector, such that the amount of racing of the engine falls within a predetermined range.

Abstract: A shift timing detecting system for detecting the start of a shift of an automatic transmission A in terms of a change in the R.P.M. of a predetermined rotary member after a shift command has been outputted. The shift timing detecting system comprises: a detector for detecting a change in the output R.P.M. of the automatic transmission; an arithmetic processor for arithmetically processing the change in the output R.P.M. with different coefficients to determine two processed values: a comparator for comparing the two processed values: and a shift start decider 5 for deciding the start of the shift on the basis of the result of the comparison. Since the shifting situation can be grasped from the change in the output torque accompanying the start of the shift and the change in the output R.P.M. caused by the former change, the start of the shift can be accurately detected without any time delay.