A displacement pump arrangement, method for operating the displacement pump arrangement and a control device for controlling the displacement pump arrangement provide rotational-speed-variable control of an expeller pump unit for feeding a fluid. The arrangement includes an expeller pump and a drive, the drive being composed of an electric drive motor and a frequency converter, and a control device. The control device controls a state value such as a final pressure of the expeller pump a setpoint value. The control device detects state values of a control variable are supplied by the drive, in particular relating to the position, rotational speed and torque of the drive motor, and adjusts the displacement pump output to reach the setpoint value without using sensors.

A system may include multiple strain gauges and multiple position sensors positioned on multiple pressure pumps. The strain gauges may measure strain in chambers of the pressure pumps. The position sensors may measure positions of rotating members of the pressure pumps. One or more computing devices may be communicatively couplable to the strain gauges and the position sensors to determine an adjustment to a flow rate of fluid through at least one pump using a strain measurement and a position measurement for the at least one pump such that a timing of changes in composition of the fluid delivered to into a first manifold at an input for the pressure pumps matches the timing of the changes in composition of the fluid delivered from a second manifold at an output for the pressure pumps.

Disclosed is a hose pump rotor, which facilitates the adjustment of the positions of rollers in a radial direction such that a hose is squeezed to a moderate extent. A main rotating shaft comprises a main shaft and a rotor base which are fixedly connected to each other, roller support arms are symmetrically arranged on the rotor base and outer ends thereof are connected to rollers, with axes of the rollers being parallel to an axis of the main shaft, the roller support arms and the rotor base form a radially-displaceable limiting fit, and the roller support arms are fixedly connected to the rotor base via locking components. The roller support arms can be displaced on the rotor base in the radial direction and can be fixed by locking same via the locking components, that is to say, the positions where the rollers are fitted to the hose are adjusted, so that the force exerted by the rollers on the hose can be ensured, and normal operation of the hose can be guaranteed.

An ocular drainage system is provided for treating diseases that produce elevated intraocular pressures, such as glaucoma, wherein the system includes an implantable device and an external control unit, the implantable device includes a non-invasively adjustable valve featuring at least one deformable tube and a disk rotatably mounted within a housing, such that rotation of the disk using the external control unit causes the disk to apply a selected amount of compression to the deformable tube, thereby adjusting the fluidic resistance of the deformable tube and regulating the intraocular pressure.

In some implementations, a controller may obtain an indication of a first crank angle associated with a first pump, of a dual-pump single-power source system, that is mechanically connected to a power source of the dual-pump single-power source system via a first clutch. The controller may obtain an indication of a second crank angle associated with a second pump, of the dual-pump single-power source system, that is mechanically connected to the power source via a second clutch. The controller may determine that a difference between the first crank angle and the second crank angle is outside of a tolerance of a crank angle difference value. The controller may modulate a fluid pressure associated with at least one of the first clutch or the second clutch to cause the difference between the first crank angle and the second crank angle to be within the tolerance of the crank angle difference value.

In some implementations, a controller may obtain a set of measurement values associated with the dual-pump single-power source system, wherein the set of measurement values includes at least one of one or more speed measurements associated with a clutch that is coupled to a power source and a first pump of the dual-pump single-power source system, a measurement value indicating an output speed of the power source, or a first crank angle associated with the first pump and a second crank angle associated with a second pump of the dual-pump single-power source system. The controller may detect that the clutch is experiencing slippage based on comparing at least two measurement values of the set of measurement values. The controller may perform an action to cause the clutch to disengage a mechanical connection between the first pump and the power source while the power source is running and is mechanically connected to the second pump.

Presented herein are systems and methods for attenuating flow ripple generated by a hydraulic pump. In certain aspects, a method and system for operating a hydraulic positive displacement pump according to a stabilized command profile are disclosed, such that flow ripple generated by operation of the pump according to the stabilized command profile is attenuated as compared to operation of the pump according to a corresponding nominal command profile. In other aspects, a pressure-balanced active buffer is disclosed that allow for at least partially cancelling flow ripple in a hydraulic circuit comprising a pump. In another aspect, a method for generating ripple maps for a pump is disclosed. Such ripple maps may be used, for example, to determine the stabilized command profile used to operate the pump, or may be used by the pressure-balanced active buffer to counteract ripple in the hydraulic circuit.

A monitoring system can include a position sensor coupled to a pump to sense a position of a rotating assembly member of the pump and generate an associated position signal. The position signal can be used to determine a position of a displacement member in a chamber in a fluid end of the pump. The monitoring system can include a strain gauge to measure strain in the chamber and generate an associated strain signal. The strain signal can be used to determine an actuation point for a valve in the chamber. A computing device can determine an actuation delay of the valve by correlating the position of the displacement member in the chamber with the actuation point for the valve. The actuation delay can represent the actuation point relative to the position of the displacement member during operation of the pump.

A Metering pump includes a displacement element (4), a drive system with an electric drive motor (12) driving the displacement element (4) and a control device (22) controlling the electric drive motor (12). The control device (22) is configured in such a manner that it detects the current position of the displacement element (4), detects the torque (M) of the electric drive motor (12) at several positions of the displacement element (4) and monitors the torque (M) in relation to the position of the displacement element (4), and a method for controlling such metering pump.

An anti-ripple injection method for injecting an anti-ripple signal into a control system of a pump is disclosed. The control system controls an electric motor via an electric motor drive, and the electric motor drives the pump. The anti-ripple signal causes pressure ripples in the pump output to be at least partially cancelled. The anti-ripple injection method includes: injecting an anti-ripple signal of any waveform into the control system, the anti-ripple signal being represented by the following equation: f()=.sub.mA.sub.m cos(m+.sub.m), wherein is the rotation angle of the motor shaft, m is the order of a signal harmonic in the anti-ripple signal, A.sub.m and .sub.m are parameters with respect to the m.sup.th signal harmonic. A control system of a pump including the anti-ripple injection apparatus, and a pump system including the control system are also disclosed.