A multi-channel positive displacement piston pump apparatus includes a motor and a plurality of positive displacement piston pumps driven by the motor. The plurality of pumps are aligned in a stacking direction, and each pump has an intake port and an outlet port, wherein the intake ports and the outlet ports of all pumps face in the same direction generally perpendicular to the stacking direction. In a method for retrofitting a positive displacement piston pump for use in a multi-channel pumping apparatus, an outlet port of a pump housing of the pump and a flush outlet port of the pump housing are plugged and an alternative fluid path is formed within the pump housing. The outlet port is disposed in line with an inlet port of the pump housing but on an opposite side of the pump housing. The flush outlet port is disposed in line with a flush inlet port of the pump housing but on an opposite side of the pump housing. In this way, the alternative fluid path is formed between the inlet port and the flush inlet port.

A pump may generally include a frame including a reservoir. The reservoir stores a hydraulic fluid. The pump may also include a motor assembly supported by the frame and a pump assembly operably driven by the motor assembly. The pump assembly is in fluid communication with the reservoir and configured to dispense the hydraulic fluid out of the frame. The pump assembly includes a first piston and a second piston, wherein the first piston dispenses hydraulic fluid out of the frame between a first pressure and a second pressure greater than the first pressure, and the second piston dispenses hydraulic fluid out of the frame between the first pressure and a third pressure, the third pressure being greater than the second pressure.

In an example, a fluid pump includes a shifter having a first end and pivotable about a second end, a cam rotatably engaged with the shifter, wherein the cam is to rotate about a cam shaft axis if the shifter pivots about the second end, a diaphragm fluidly engaged with a fluid cavity, a collar movable with a cam surface of the cam, wherein the collar is to compress the diaphragm so as to decrease the volume of the fluid cavity, a fluid inlet having a one-way inlet valve to only allow fluid into the fluid cavity, and a fluid outlet having a one-way outlet valve to only allow fluid out of the fluid cavity, wherein the one-way outlet valve is to allow fluid out of the fluid cavity upon the volume of the fluid cavity being decreased.

In an example, a fluid pump includes a shifter having a first end and pivotable about a second end, a cam rotatably engaged with the shifter, wherein the cam is to rotate about a cam shaft axis if the shifter pivots about the second end, a diaphragm fluidly engaged with a fluid cavity, a collar movable with a cam surface of the cam, wherein the collar is to compress the diaphragm so as to decrease the volume of the fluid cavity, a fluid inlet having a one-way inlet valve to only allow fluid into the fluid cavity, and a fluid outlet having a one-way outlet valve to only allow fluid out of the fluid cavity, wherein the one-way outlet valve is to allow fluid out of the fluid cavity upon the volume of the fluid cavity being decreased.

An electric drive pump system includes a power end and a detachable transmission assembly. The transmission assembly is mounted to the power end and is configured to provide rotational power to the power end through a plurality of electric motors. The plurality of electric motors use a gearbox to drive an output spline that engages the power end. A control module is used to regulate the performance characteristics of the plurality of electric motors. A temperature regulation assembly is configured to regulate the temperature of the transmission assembly and the power end.

An electric drive pump system includes a power end and a detachable transmission assembly. The transmission assembly is mounted to the power end and is configured to provide rotational power to the power end through a plurality of electric motors. The plurality of electric motors use a gearbox to drive an output spline that engages the power end. A control module is used to regulate the performance characteristics of the plurality of electric motors. A temperature regulation assembly is configured to regulate the temperature of the transmission assembly and the power end.

A novel embodiment of a drive mechanism for use in a pump, for example, of the type that would be used in a wearable drug delivery system, comprises, a cylindrically-shaped slider element configured with a channel on a circumferential surface thereof defining one or more zig-zag-shaped tracks therethrough. One or more pegs are engaged within the tracks, such that a back and forth longitudinal motion of the slider element along a radial axis of the cylinder causes movement of the pegs along one of the tracks through the channel, thus providing a movement of the pegs around the circumference of the cylinder which imparts a rotational motion to a header element disposed co-axially with the slider. The header element is in turn connected to a gear train, for example, a planetary gear box, which is coupled to the pump via a linkage or other type of mechanism.

A novel embodiment of a drive mechanism for use in a pump, for example, of the type that would be used in a wearable drug delivery system, comprises, a cylindrically-shaped slider element configured with a channel on a circumferential surface thereof defining one or more zig-zag-shaped tracks therethrough. One or more pegs are engaged within the tracks, such that a back and forth longitudinal motion of the slider element along a radial axis of the cylinder causes movement of the pegs along one of the tracks through the channel, thus providing a movement of the pegs around the circumference of the cylinder which imparts a rotational motion to a header element disposed co-axially with the slider. The header element is in turn connected to a gear train, for example, a planetary gear box, which is coupled to the pump via a linkage or other type of mechanism.

Pump subsystem for fluid delivery (e.g., in a wearable patch pump) comprises a fluid chamber with pumping motion and a valve shaft assembly with valving motion, both being driven by the same drive mechanism. Fluid chamber has variable volume chamber provided by a piston driven by the drive mechanism and translated relative to a plug in the pump housing. Piston extends the fluid chamber during an intake stroke and retracts the fluid chamber during a discharge stroke. Valve assembly has at least one valve shaft controllably translated by the drive mechanism to selectively align a first throughway with an opening in the pump chamber and a fluid intake port for an intake stroke to draw fluid into the fluid chamber, and align a second throughway with the opening in the pump hamber and a fluid discharge port for an discharge stroke to discharge fluid from the fluid chamber.

A tappet, which may be a pump actuator, comprises a body that is a contiguous piece of ferrous metal. The body comprises an outer shell and an inner side. The outer shell is case-hardened to a first hardness, and the inner side comprises a second hardness less than the first hardness. The outer shell comprises a bore-running surface and an outward projection that is operative as an anti-rotation guide feature and projects outwardly from the bore-running surface. The body further comprises two parallel planar surfaces disposed at a drive-input end of the body and an axle hole defined in each of the two parallel planar surfaces. The tappet further comprises an axial support pin mounted through the axle hole of each of the two parallel planar surfaces and a cam follower mounted to the body via the axial support pin.