Abstract:
The invention provides a variable speed hydraulic pump designed to operate at a maximum horsepower throughout its pressure range by adjusting motor speed according to motor load parameters. In particular, the variable speed hydraulic pump includes a hydraulic pump unit coupled to a variable speed electric motor by a drive unit and to a hydraulic fluid tank for pressurizing and pumping hydraulic fluid when operated by the motor. A motor controller is electrically connected to the motor to supply drive signals to the motor based on electrical characteristics of the drive signals which are dependent on the load exerted on the motor. Suction from the load is provided by both the main pump and a bidirectional supercharging pump by reversing the direction of the motor and shifting a 4/3 valve to connect the main pump inlet to the load and its outlet to tank. In addition, the controller reduces the motor speed at the maximum rated pressure to just maintain the pressure, to reduce the amount of fluid pumped through the maximum pressure relief valve.
Abstract:
Elektronische Steuerungseinrichtung für einen Kältemittelkompressor, welcher zumindest eine Antriebseinheit sowie einen mit der Antriebseinheit in Wirkverbindung stehenden Kompressionsmechanismus mit zumindest einem sich in einem Zylinder eines Zylinderblocks des Kältemittelkompressors in einem Betriebszustand des Kältemittelkompressors zur betriebsgemäßen Verdichtung von Kältemittel hin- und herbewegenden und über eine Kurbelwelle der Antriebseinheit angetriebenen Kolben umfasst, wobei die elektronische Steuerungseinrichtung des Kältemittelkompressors zumindest dazu eingerichtet ist, zumindest einen physikalischen Prozessparameter, vorzugsweise die Drehgeschwindigkeit (n) der Kurbelwelle oder die Leistungsaufnahme des Kältemittelkompressors, zu detektieren, ein an den Kältemittelkompressor gerichtetes Abschaltsignal zu detektieren, welches Abschaltsignal eine Betriebsphase des Kältemittelkompressors beendet, in welcher Betriebsphase der Kältemittelkompressor mit einem positiven Betriebsdrehmoment bestimmungsgemäß betrieben wird, sowie dazu eingerichtet ist, ein von der Antriebseinheit an die Kurbelwelle zur Einstellung deren Drehgeschwindigkeit (n) angelegtes Drehmoment zu regeln, wobei die elektronische Steuerungseinrichtung weiters dazu eingerichtet ist, unmittelbar nach Detektieren des Abschaltsignals ein Bremsmoment an die Kurbelwelle anzulegen, wobei das Bremsmoment dem während der Betriebsphase vorherrschenden positiven Drehmoment entgegengerichtet ist und der Betrag dieses Bremsmomentes eine Funktion des detektierten physikalischen Prozessparameters, vorzugsweise der Drehgeschwindigkeit (n) der Kurbelwelle oder der Leistungsaufnahme des Kältemittelkompressors, ist.
Abstract:
The invention relates to a method and to a device for operating an electric peristaltic hose pump, in particular a hose pump for transporting fluids in medical-technical devices, in particular extracorporeal blood treatment devices. In order to monitor the regular operation of a hose pump, the power consumption of the pump or a physical variable in correlation with the power consumption, in particular the pump flow, is monitored. According to the invention, the pump flow comprises a periodically non-altering direct component which is superimposed on a periodically altering alternating component. In order to monitor the regular operation of the hose pump, the alternating component of the power consumption in relation to the direct component of the power consumption is monitored as whether it increases and/or decreases during blood treatment.
Abstract:
Embodiments of a system, controller, and method for operating a plurality of pumps for a turbine driven fracturing pump system used in hydraulic fracturing are disclosed. In an embodiment, a method of operating a plurality of pumps associated with a hydraulic fracturing system includes receiving a demand Hydraulic Horse Power (HHP) signal. The demand HHP signal may include the Horse Power (HP) required for the hydraulic fracturing system to operate and may include consideration for frictional and other losses. The method further includes operating available pump units at a percentage of rating below Maximum Continuous Power (MCP) level, based at least in part on the demand HHP signal. Furthermore, the method may include receiving a signal for loss of power from one or more pump units. The method further includes operating one or more units at MCP level and operating one or more pump units at Maximum Intermittent Power (MIP) level to meet the demand HHP signal.
Abstract:
A method of controlling a hydraulic system having a variable displacement pump operatively coupled to an engine. The method includes detecting a speed of the engine, and determining a desired power value of the pump. The method also includes identifying an allowable power value that may be expended by the pump at the detected speed. The method also includes selecting a pump power value. The selected pump power value is the lower of the allowable power value and the desired power value. The method further includes adjusting the pump to deliver the selected pump power value.
Abstract:
The invention further relates to an apparatus and method for monitoring a peristaltic hose pump, in particular a peristaltic hose pump of an extracorporeal blood treatment device. The power consumed by the pump and/or the pressure in the tubing segment upstream or downstream of the pump is/are measured during operation of the pump and test signals I1(t), I2(t) which are associated with the individual displacement members are determined. The power or pressure signals associated with the individual displacement members significantly differ from each other during abnormal operation of the hose pump, but no significant differences can be recognized during normal operation of the pump.
Abstract:
The invention further relates to an apparatus and method for monitoring a peristaltic hose pump, in particular a peristaltic hose pump of an extracorporeal blood treatment device. The power consumed by the pump and/or the pressure in the tubing segment upstream or downstream of the pump is/are measured during operation of the pump and test signals I1(t), I2(t) which are associated with the individual displacement members are determined. The power or pressure signals associated with the individual displacement members significantly differ from each other during abnormal operation of the hose pump, but no significant differences can be recognized during normal operation of the pump.
Abstract:
A method of monitoring the operation of a compressor includes sensing a parameter on a housing of the compressor from a device placed on the housing, generating a representative sensor signal in response to the sensed parameter, transmitting from the device a data signal related to the representative sensor signal, and receiving the data signal at a location remote from the housing. Other methods and an apparatus for monitoring the compressor are further disclosed.
Abstract:
The invention provides a variable speed hydraulic pump designed to operate at a maximum horsepower throughout its pressure range by adjusting motor speed according to motor load parameters. In particular, the variable speed hydraulic pump includes a hydraulic pump unit coupled to a variable speed electric motor by a drive unit and to a hydraulic fluid tank for pressurizing and pumping hydraulic fluid when operated by the motor. A motor controller is electrically connected to the motor to supply drive signals to the motor based on electrical characteristics of the drive signals which are dependent on the load exerted on the motor. Suction from the load is provided by both the main pump and a bidirectional supercharging pump by reversing the direction of the motor and shifting a 4/3 valve to connect the main pump inlet to the load and its outlet to tank. In addition, the controller reduces the motor speed at the maximum rated pressure to just maintain the pressure, to reduce the amount of fluid pumped through the maximum pressure relief valve.
Abstract:
A control system for a hydraulic pump of the variable displacement type using a pair of coaxially arranged pressure responding pistons. The control system comprises a servo valve for controlling a conduit of pump delivery pressure which is to be applied to a larger chamber of a servo cylinder in response to the pump delivery pressure and external pilot pressure. The servo valve includes a servo spool for controlling the conduit in order to control the pump delivery pressure, a servo sleeve for movably receiving the servo spool, a pump delivery pressure responding piston for biasing the servo spool in response to the pump delivery pressure, an external pilot pressure responding piston adapted for biasing the servo spool in response to the external pilot pressure and being coaxially arranged with the pump delivery pressure responding piston. The lever assembly causes the servo sleeve to move in accordance with the movement of the servo piston. The lever assembly has an inclined surface part for causing displacement of the servo piston as a function of displacement of the pressure responding pistons to show a characteristic hyperbola.