Abstract: In a gate driver device, cathode conductor 2, gate conductor 3, and positive and negative conductors 8 and 9 between the principal turn-on and turn-off capacitors and MOSFET switching elements Q11-Q1i and Q21-Q2j are disposed on a wide plate. A thin insulation layer is inserted between conductor 3 and conductors 8 and 9. Numerous chip-type ceramic capacitors C11-C1m and C21-C2n to be used as principal capacitors are arranged in rows in the space between conductor 2 and conductors 8 and 9. The gate voltage of switching elements Q11-Q1i is reduced exponentially by time constant circuit TC, and the leak inductance of transformer Thf is employed to smooth the charging current.

Abstract: Disclosed is a method of controlling an internal combustion engine driven electric vehicle in power operation of the vehicle, in which control is made so that a voltage of a DC intermediate circuit is maintained to a first constant DC voltage in a first speed range of from a zero vehicle speed to a first vehicle speed, the voltage of the DC intermediate circuit is changed in proportion to the vehicle speed in the second speed range of from the first vehicle speed to a second vehicle speed, and the voltage of the DC intermediate circuit is made to be a second constant DC voltage in the third speed range not lower than the second vehicle speed, and control is further made so that an AC output of the second power converter is made to have a variable voltage and a variable frequency in the first and second speed ranges, while the AC output of the second power converter is made to have a constant voltage and a variable frequency in the third speed range.

Abstract: Disclosed is a method of controlling an internal combustion engine driven electric vehicle in power operation of the vehicle, in which control is made so that a voltage of a DC intermediate circuit is maintained to a first constant DC voltage in a first speed range of from a zero vehicle speed to a first vehicle speed, the voltage of the DC intermediate circuit is changed in proportion to the vehicle speed in the second speed range of from the first vehicle speed to a second vehicle speed, end the voltage of the DC intermediate circuit is made to be a second constant DC voltage in the third speed range not lower than the second vehicle speed, and control is further made so that an AC output of the second power converter is made to have a variable voltage and a variable frequency in the first and second speed ranges, while the AC output of the second power converter is made to have a constant voltage and a variable frequency in the third speed range.

Abstract: Disclosed is a method of controlling an internal combustion engine driven electric vehicle in power operation of the vehicle, in which control is made so that a voltage of a DC intermediate circuit is maintained to a first constant DC voltage in a first speed range of from a zero vehicle speed to a first vehicle speed, the voltage of the DC intermediate circuit is changed in proportion to the vehicle speed in the second speed range of from the first vehicle speed to a second vehicle speed, and the voltage of the DC intermediate circuit is made to be a second constant DC voltage in the third speed range not lower than the second vehicle speed, and control is further made so that an AC output of the second power converter is made to have a variable voltage and a variable frequency in the first and second speed ranges, while the AC output of the second power converter is made to have a constant voltage and a variable frequency in the third speed range.

Abstract: A floating seal device includes a fixed side O-ring held by a fixed side seal retainer, a rotary side O-ring held by a rotary side seal retainer, and fixed side and rotary side seal rings pressed against each other by the respective O-rings so that their opposed surfaces may be slidably held in contact with each other. Such device is improved in order to eliminate oil leakage, to reduce mechanical power loss, to avoid an increase in weight and to shorten the replacement time for lubricant oil by mounting an oil absorbing member made of felt or the like to a peripheral wall surface formed on the opposed surface of the rotary side seal ring.

Abstract: An electric wheel drive for a wheel body having a drive housing with an interior side facing toward the body and having an opposite exterior side facing away from the body includes a drive motor which has a drive shaft facing the exterior side. Second stage star-type reduction gear and a first stage planetary reduction gear are connected to the drive shaft of the drive motor and they are located adjacent the exterior side. The second stage gear has an outer driving gear surface which is in driving engagement with the wheel hubs of a tire. The construction includes a cooling air passage extending from said housing interior side past said drive motor first and then through first and second gear stages to the exterior side.

Abstract: The invention is a hydraulic control system for use in positioning and clamping a movable object on a support, which system is adapted to be connected to a source of pressurized hydraulic fluid, to a hydraulically operated piston-cylinder assembly connected to the movable object for moving the movable object and to a hydraulically operated clamp and which comprises a path for the supply of pressurized fluid to and from the hydraulically operated clamp, a check valve in the path which check valve normally prevents return of fluid from the hydraulically operated clamp, a hydraulically operated pilot piston movable between a non-actuating position and an actuating position in which it opens the check valve, a path for the supply of pressurized fluid to the piston-cylinder assembly, which path is connected on its high pressure side to the hydraulically operated pilot piston, and a switching valve for controlling the supply of pressurized fluid to the piston-cylinder assembly, the arrangement being such that when

Abstract: A slide mechanism comprising a movable frame mounted for generally horizontal longitudinal movement along a support frame, the movable frame comprising first and second projections which extend transversely of the support frame adjacent an upper portion and a lower portion respectively of the support frame, and a slide member releasably mounted in a first groove formed in the under side of the first projection and having a second groove arranged for sliding movement along a guide rail disposed longitudinally on the upper side of the said upper portion of the support frame, wherein one of the first and second grooves has a wedge shaped cross-section and the other groove has a semi-cylindrical cross-section, there being provided means for urging together an inclined face on the second projection and an inclined face on a downward projection of the said lower portion of the support frame which is disposed in a recess in the second projection.

Abstract: A mounting apparatus for releasably mounting attachments on a vehicle body, the apparatus comprising a bracket for securing to the vehicle body and a connecting member for securing to an attachment for the vehicle, the bracket comprising two vertically spaced projections each having an upwardly facing notch, and the connecting member having a respective pin for engaging with the notch of each projection to support the connecting member on the bracket and a locking member movable transversely of the upper projection and engageable with a contact surface formed on an underside of the upper projection to lock the respective pin in the upper projection.

Abstract: A power slide mechanism comprising a supporting frame, a moving frame mounted slidable on said supporting frame, double-acting fluid pressure device including a cylinder, a piston fitted slidably in the cylinder and a respective piston rod fixed to the piston at each end thereof and penetrating through the cylinder so that one end of each piston rod projects from respective end face of the cylinder, and a respective engaging and fastening device mounted at each end of the supporting frame and adapted to releasably engage the free end of a respective one of the piston rods.

Abstract: The invention is a control system for a hydraulic clamping device adapted to be connected to a source of pressurized hydraulic fluid and to a hydraulically operated clamp, which system comprises a path for supply of pressurized fluid to and from the clamp, a check valve in the said path, a hydraulically operated pilot piston movable between a non-actuating position and an actuating position in which it urges open the check valve, means to hold the pilot piston in the actuating position and thereby maintains the check valve open and a switching means for controlling the supply of pressurized fluid to and from the pilot piston, the switching means being capable of occupying a neutral position, a position in which pressurized fluid is supplied to the pilot piston to urge the pilot piston to the actuating position to open the check valve and a position in which pressurized fluid is supplied to the pilot piston to return the pilot piston to the non-actuating position and thereby permit the check valve to close.