Abstract:
A hydraulic drive unit of a press machine and a swash plate type variable capacity axial piston pump to use for a hydraulic drive unit. Discharge of the pump and the direction of the hydraulic pressure can be controlled at high speed, and the direction of the hydraulic pressure and the timing of the discharge can coincide. The selector device 12 that includes spool valves in parallel is used in place of a servo valve. An electric motor 30 for driving the pump and cam of the axial piston pump 11 and an electric motor 47 for driving the selector cam of the selector device 12 are controlled cooperatively by commands from the numerical control device 14. Two spools 44a, 44b of the selector device 12 perform changeover actuation alternately. Synchronous control of the discharge of the axial piston pump 11 and the flowing direction change of working fluid to the hydraulic pressure cylinder 1 are done, so that the piston 1a of the hydraulic pressure cylinder 1 is made to move up and down.
Abstract:
A variable capacity wobble plate compressor of the type that a wobble plate mounted on a drive shaft is swung axially of the drive shaft as the drive shaft rotates, and pistons connected to the wobble plate make reciprocating motions in response to swinging of the wobble plate, wherein a change in the angularity of the wobble plate causes a change in stroke of the reciprocating motions of the pistons whereby the capacity of the compressor is varied. A sensing element arranged on the wobble plate is moved along a predetermined orbital path together with swinging of the wobble plate. A sensor arranged on a compressor housing generates an electric signal when the sensing element passes by the sensor as the wobble plate swings. A control unit determines the rotational speed of the compressor and the angularity of the wobble plate on the basis of the electric signal from the sensor. The sensor is so located as to align with a predetermined location between an axial center of the predetermined orbital path of swinging of the sensing element and an extreme possible point toward the pistons, when the wobble plate assumes the minimum angularity.
Abstract:
Disclosed is a device for controlling or measuring operational parameters of an axial piston machine. The tilting plate which engages and adjusts the stroke of the piston is provided with two opposite pivot pins supported in fixed bearings. At least one pivot pin is provided with a shearing stress sensor preferably in the form of a magnetoelastic feeler which produces electrical signals the pulsation of which is indicative of rotational speed and the magnitude of the signal is proportional to pressure applied by the pistons and thus to the delivery of the machine. A second sensor is coupled to the tilting plate to indicate the angular displacement of the latter. The output signals from the sensors are separated into the pressure dependent signals, frequency dependent signals and angular displacement signals which upon multiplication are applied to a programmable data processing unit. The output of the unit is supplied to a solenoid operated proportional valve which controls pressure fluid for hydraulic setting motors which adjust the angular displacement of the tilting plate.
Abstract:
The invention relates to a stroke-adjustable air conditioning compressor, in particular for motor vehicles, comprising a drive mechanism for pistons that move back and forth, the pistons being driven by means of an adjusting plate, such as a pivoting plate, pivoting ring or swash plate at an adjustable pivoting angle. The position of the pivoting angle is influenced inter alia by compressive forces, inertial forces and elastic forces that are active in the drive mechanism.
Abstract:
A peristaltic pump for propelling liquid through a flexible tube segment. The pump has a cam shaft which carries a plurality of cams each having a driving surface. The driving surfaces of adjacent cams are spaced at an angle to each other about the cam shaft. The pump also has a plurality of cam followers which are each reciprocal in a common direction perpendicular to the axis of the cam shaft. Each cam follower has a cam surface riding on the driving surface of a cam and a tube engaging surface for engaging the flexible tube segment. At least one of the cam followers is a restriction cam follower of which the tube engaging surface engages the flexible tube segment for a longer period than that of the other cam followers. The pump also has a motor for rotating the cam shaft whereby the cams cause the cam followers to each engage and occlude the flexible tube segment to form a propagating depression wave in the flexible tube segment for propelling liquid. The restriction cam followers prevent back flow of the liquid.
Abstract:
Control system and control method of a variable displacement hydraulic pump wherein the system includes a detection sensor for detection of the actually set displacement and a control unit for current control of a couple of solenoids controlling displacement increase and decrease.
Abstract:
A method for controlling an electrical drive of an electrically driven air compressor of a motor vehicle and a corresponding control circuit. A prevailing load torque of the air compressor that is applied at a drive shaft of the compressed air compressor is estimated as a function of at least one operating parameter and is fed forward as an estimated disturbance variable to the control circuit of the electrical drive to reduce a control error produced as a result of the prevailing load torque.
Abstract:
Disclosed is a supplying device of fixed colorants volume for a colorant dispenser. The supply device includes: a colorant source; a cylinder body having multiple piston cylinders arranged around a circumferential direction thereof; a swashplate having an oblique surface and arranged substantially coaxially with the cylinder body; multiple piston mechanisms, where each piston mechanism includes a piston rod and a piston connected to the piston rod, the piston rod has a rolling abutment structure abutting against the oblique surface, and the piston is constructed to be capable of making a stroke movement in the corresponding piston cylinder by means of rotation of the swashplate; an actuator for actuating the swashplate; a controller operatively connected to the actuator to control the amount of rotation of the swashplate; and an outlet for dispensing a colorant. Preferably, the supply device further includes an axial reset mechanism and a circumferential reset mechanism.
Abstract:
A hydraulic motor unit including a hydraulic motor (1′) which is connected to two working lines (3,4). The swiveling angle (α) of the hydraulic motor (1′) is adjustable by an adjusting unit (7) which is provided with a regulating piston (8) having two piston surfaces (9, 10). The regulation pressure acting on a first piston surface (10) in a regulation pressure chamber (12) can be adjusted by a control valve (13). The control valve (13) adjusting the regulation pressure is movable between two final positions. The pressure of a working line (3, 4) is applied to a first measuring surface (23) of the control valve (13) adjusting the regulation pressure while a second, opposite measuring surface (25) of the control valve (13) is impinged upon by a control pressure piston (34) at a force that depends on the control pressure only once a threshold value of a pipe (28, 18′) supplying control pressure has been exceeded.
Abstract:
Disclosed is a braking system of an automobile, which can produce and store an electric power by means of the energy generated when the automobile is braked, thereby increasing efficiency in energy use, and simultaneously which can perform an anti-lock braking function and a traction control function. In the braking system, a master cylinder generates a hydraulic pressure when the brake pedal is pressed. A variably exhausting pump unit performs a pumping operation by the hydraulic pressure from the master cylinder. A control section senses a traveling state of the automobile and controls so that a proper braking force is applied to a wheel of the automobile. A flow control valve providing the variably exhausting pump unit with the braking force. A generating section generates electricity by means of a bypassed hydraulic pressure according to the order of the control section.