Abstract: The invention relates to a thermostat unit adapted to be attached to a radiator valve of the type having a rotatable adjusting spindle and a surrounding ring shaped housing portion. The thermostat has a rotary knob unit with a body portion and a smaller diameter neck portion which connects to the valve spindle. The thermostat has a base unit with a supporting ring portion which surrounds said rotary knob body portion and a tightening ring portion which is attachable to the valve housing. The base unit supporting ring portion provides lateral or transverse support for the knob unit body portion to prevent breaking thereof when the knob unit body portion is subjected to large transverse forces resulting from accidental blows to which the knob unit body portion may be subjected.

Abstract: The invention relates to a hydraulic planetary piston type machine and particularly to the rotary slide valve thereof. This type of machine has a rotary piston gear having rotational and orbital movement and a cardan type shaft connects the slide valve to the piston gear. The valve has inlet and outlet, annularly shaped, axially spaced distributor grooves in axially spaced relation. Alternately arranged inlet and outlet stub grooves extend axially from the distributor grooves into axially overlapping relation. The stub grooves in the valve have a commuting action with circumferentially arranged ports in the casing to provide for feeding and exhausting pressurized fluid to and from expanding and contracting chambers formed by the piston gear. In smaller machines the correspondingly smaller flow passages present sufficient flow resistance to substantially affect the efficiency of the machine.

Abstract: The invention relates to a valve assembly. A closure member for the valve unit is controlled directly or indirectly by a movable wall of an expansible chamber filled with a refrigerant medium having vapor and liquid phases. The pressure exerted by the vapor phase of the medium provides a bias which is directly related to the temperature of the liquid phase. A heat transfer element such as a heating resistor in the liquid phase is heated or allowed to cool in a controlled manner by an external control unit. A temperature responsive sensor element in the liquid phase of the medium is part of a feedback system for the control unit which allows a selected temperature to be maintained in the chamber which results in a desired constant pressure to be maintained in the chamber. A pilot valve unit is disposed between the valve closure member and the movable wall. An expansible chamber behind the closure member houses a spring for biasing in a valve closing direction.

Abstract: The invention relates to a valve assembly. A closure member for the valve unit is controlled directly or indirectly by a movable wall of an expansible chamber filled with a refrigerant medium having vapor and liquid phases. The pressure exerted by the vapor phase of the medium provides a bias which is directly related to the temperature of the liquid phase. A heat transfer element such as a heating resistor in the liquid phase is heated or allowed to cool in a controlled manner by an external control unit. A temperature responsive sensor element in the liquid phase of the medium is part of a feedback system for the control unit which allows a selected temperature to be maintained in the chamber which results in a desired constant pressure to be maintained in the chamber. A pilot valve unit is disposed between the valve closure member and the movable wall. An expansible chamber behind the closure member houses a spring for biasing in a valve closing direction.

Abstract: The invention relates to an electrohydraulic control assembly of the type having a slide valve unit for controlling the operating direction of a hydraulic servomotor. The assembly includes a bridge circuit between the pressure source and the drain tank which has a pressure operated valve in each of its four branches. Diagonally opposite bridge terminals between the supply and exhaust branches of the bridge circuit are connected operating chambers on opposite sides of the slide valve unit. The bridge circuit valves are operated by solenoid valves to achieve selective directional operation of the slide valve unit.

Abstract: The invention relates to a gerotor type of rotary piston machine. In this type of device an externally toothed rotor member is eccentrically offset relative to an internally toothed stator member and in operation these members mesh to form expanding and contracting cells on opposite sides of the line of eccentricity. There is a shaft means for driving the rotor and a distributing valve for feeding and exhausting the cells. The distributing valve, which is normally connected to the drive shaft, is connected to the rotor member for movement therewith adjacent to the rotor and stator member. An annular chamber is formed between the periphery of the distributing valve and the interior of the casing. One set of the distributing ports is formed as ports within the confines of the periphery of the valve. The other set of distributing ports are formed by the periphery of the valve.

Abstract: The invention relates to a heat emitter unit for a hot water heating system. The heat emitter unit is characterized by a valve and a heat emitter unit being integrated in a manner so that the valve casing and the heat emitter pipe to which fins are attached are in axial alignment. The heat emitter pipe has a central tube arrangement which provides in parallel a central bypass and a surrounding valve controlled passage. Heat from hot water flowing through the surrounding valve controlled passage is transferred through the finned pipe to the fins.

Abstract: The invention relates to a hydrostatic control unit of the metering type utilized for some automotive type power steering systems. The control unit has a valving section with inlet and outlet ports connectable to a pump and a tank and two working ports connectable to opposite sides of a bidirectional servomotor which is connectable to wheel steering linkage. A metering motor controlled by the valving section supplies and exhausts metered fluid to and from the servomotor through the two working ports of the valving section. The valving section has a single movable slide element cooperable with a stationary housing member. A gearing unit which may be of the planetary type is provided having two inputs and one output with the two inputs being connectable to the vehicle steering wheel and the metering motor input shaft and the output being connectable to the slide valve element.

Abstract: The invention relates to a measuring probe for the acoustic determination of the specific gravity of a liquid. The probe includes a holder to which is attached at opposite ends thereof a ceramic piezoelectric transducer disc and a reflector disk. A reference element having a known acoustical impedance has one end thereof abutting the transducer disc and the other end thereof spaced from the reflector disc to form a sampling space therebetween.

Abstract: The invention relates to control apparatus for feeding liquified refrigerant to the evaporator of a refrigeration system. A main valve controlled by a differential pressure type servo-element controls the flow of refrigerant to the evaporator. A float type pilot valve has a nozzle and closure member controlled by a float which has a liquid level identical to liquid level in the evaporator. A pilot conduit which extends between the main valve and the pilot valve has first and second throttle units arranged in series. The first throttle unit controls a flow of liquid refrigerant through the pilot conduit to control the main valve. The second throttle unit controls a flow of refrigerant through the pilot conduit which is at least partially in vapor form. This arrangement with two throttle units allows control over a broader proportional range for the settings of the float in the pilot valve.

Abstract: The invention relates to a manually setable, knob-type thermostatic control assembly for radiator valves. The knob normally has a fixed or usual setting to provide a desired temperature for a room. Occasionally the setting is temporarily changed for one reason or another and the unit must be reset to its usual setting. This is facilitated herein and in the prior art by providing index markings on the relatively rotatable members. The novelty herein, however, is in providing a cap for the rotatable knob member which carries the index marking and the cap is readily adjustable relative to rotatable member in a simple manner without detaching the cap from the knob member.

Abstract: The invention relates to a brushless type electric motor having an axial air gap and is directed to a particular design and arrangement for the pole shoes thereto.

Abstract: The invention relates to a control unit for an adjustable fluid pump or motor controlled by a servomotor. The control unit is of the type having a slide valve with a neutral blocking position with supply and exhaust positions on opposite sides of the neutral position. The neutral position provides a zero pump feed condition and the improvement resides in a construction wherein the fed amount is absolutely zero. This is accomplished with a secondary valve which has a fixed part and a moveable part which moves with the actuator. The secondary valve has fluid passages which short circuit the supply and exhaust connections of the unit over a small travel range on opposite sides of the neutral position of the actuator.

Abstract: The invention relates to a starter device for single phase, asynchronous motors, the starter device being of the type which provides a PTC resistor for series starting operation with the auxiliary winding. The starter device may be used for different types of motors by reason of an arrangement of contacts for connecting the main and auxiliary windings, starting capacitors and a two phase power supply which accommodates different modes of starting operation required by different motors.Three capacitor contacts provide for connecting capacitors in different ways relative to the PTC resistor and one of two sets of winding contacts may be selected to suit a desired mode of starting operation.

Abstract: The invention relates to a motor of the type energizable by a DC voltage and having at least two parallel stator winding branches with each branch having a stator winding in series with a controllable switching element. A demagnetization branch in parallel with each stator winding branch has an oppositely poled demagnetization winding inductively coupled to the associated stator winding and a series connected diode poled oppositely of the associated switching element. When one stator winding is switched off the voltage induced in the inductively coupled demagnetization winding produces a current which flows through the associated diode and the next simultaneously switched on stator winding. In this way the magnetic energy of the switched off stator winding is rapidly reduced and is utilized to supplement the magnetic field of the simultaneously switched on stator winding.

Abstract: The invention relates to a brushless type DC motor assembly of the type having a permanent magnet rotor and a pair of poles provided with two windings, the windings having a common junction which is connectable to the positive terminal of a DC voltage source. A pair of controlled rectifiers in respective series with the windings are followed by a series branch having a smoothing choke and an electronic chopper switch, the series branch being connectable to the negative terminal of the DC voltage source. The invention is directed to an improved circuit permitting operation of the motor at higher power by providing an extinguishing circuit for the controlled rectifiers which includes a series arranged extinguishing capacitor and a swingover choke that connects the upstream sides of the controlled rectifiers. The extinguishing circuit also includes extinguishing diodes connected in antiparallel respectively to the rectifiers.

Abstract: The invention relates to hydraulic control apparatus for a servomotor of the type utilized for vehicle steering systems. Such apparatus has a control circuit controlled by a manually operated device such as a steering wheel and a power circuit connected between the servomotor and a power source such as a hydraulic pump. The power circuit includes resetting apparatus for throttling the return flow branch in a manner so that forces applied to the servomotor in the same direction as actuation are absorbed with a minimum of reactionary movement by the valves on the return flow side of the apparatus.

Abstract: The invention relates to the slide shoe arrangement of a radial piston type of machine. This type of machine has a housing with a rotatable shaft and a piston carrier mounted on the shaft. Pistons in the carrier have reciprocal and radial movement relative to the carrier and shoes attached to the pistons have sliding engagement with an annularly shaped, eccentrically adjustable, track which surrounds the carrier. The track has a spherical surface portion with a predetermined radius R1. The shoes have spherically shaped surface portions of radius R2 which engage the track, radii R2 being larger than radius R 2 to form tapered gap chambers between the spherical shoe surfaces and the spherical track surface. The shoe portions may have annularly shaped flanges contacting the track surface through the spherical shoe surfaces. The flanges are resiliently connected to the shoe portions.

Abstract: A speed regulator for a guide and follower motor assembly. A guide pulse frequency generator driven by a guide motor drives a frequency converter which drives a follower motor. The frequency converter includes a frequency regulator with a negative feed back which includes a frequency divider. Adjusting and setting circuits for the frequency divider include an up/down counter for operating the frequency divider, a resetting operation of the counter to provide a frequency indicating value for its output, an adjustable pulse generator for driving the counter, an add/subtract circuit, and a comparator responsive to the add/subtract circuit and the counter to control the pulse generator.

Abstract: The invention relates to a pumping system for supplying fluid at a variable delivery rate in accordance with demand. The system includes one pump having a variable delivery rate and one or more auxiliary pumps arranged in parallel therewith, each having a fixed delivery rate. The variable delivery pump operates over a predetermined control range between minimum and maximum rates. Each fixed delivery rate pump has on and off operating modes with the on mode delivery rate being at the maximum delivery rate of the variable delivery pump. A control unit for operating the pumps matches the pump delivery with the demand. The control unit functions to set the variable delivery pump at its minimum delivery rate when operation of the fixed delivery pump is initiated during upward demand control and for setting it at its maximum delivery rate when operation of the fixed delivery pump is terminated during downward demand control.