Claims
- 1. A liquid dispensing pump system, comprising:a pump module including a displacement piston and a piston valve disposed in a cylinder and defining a pumping chamber, wherein the displacement piston travels back and forth in the cylinder, producing suction, and discharging pumping action, a port case fitting with a plurality of ports able to communicate one at a time with a fluid slot in the piston valve based on rotation of the piston valve, and the direction of travel of the displacement piston determines the direction of flow out of any port; a motor for driving the displacement piston back and forth in the cylinder; a ratchet-actuator assembly for rotating the piston valve so that the fluid slot of the piston valve communicates with one of the plurality of ports in the port case fitting; and a motor and base assembly for supporting the pump module, the motor for driving the displacement piston, and the ratchet-actuator assembly for rotating the piston valve.
- 2. The system of claim 1, wherein the ratchet-actuator assembly includes:an actuator for rotating an actuator shaft, a cam and camshaft extending from the actuator shaft, and a ratchet extending from a ratchet shaft, wherein the actuator shaft rotates back and forth causing the cam to lower or lift a pawl to engage or disengage with a ratchet tooth and a roller clutch transfers forward rotation of the camshaft to the ratchet when the pawl is not engaged with the ratchet tooth.
- 3. The system of claim 2, wherein the actuator is a pneumatic actuator with a vane blade.
- 4. The system of claim 1, wherein the ratchet-actuator assembly transfers the forward and reverse rotation of an actuator shaft to forward rotation of a ratchet shaft coupled to the piston valve.
- 5. The system of claim 1, wherein the ratchet-actuator assembly includes:a ratchet in a housing and having ratchet teeth, wherein the ratchet is integral with or fixed to a ratchet shaft and coupled to a roller clutch, an actuator shaft with a cam and camshaft coupled to the roller clutch, and a pawl adjacent the cam, wherein the rotational position of the cam determines whether the pawl engages or disengages the ratchet teeth, and wherein the roller clutch engages when the camshaft rotates forward and disengages when the camshaft rotates back.
- 6. An apparatus for pumping fluid, comprising:a pump module, including a cylinder liner with a plurality of ports, a displacement piston slidably disposed in the cylinder liner, a piston valve with a fluid slot rotatably disposed in the cylinder liner, wherein the displacement piston and the piston valve and cylinder liner define a pumping chamber; a first motor operably driving the displacement piston back and forth; a second motor operably rotating the piston valve to align the fluid slot with each of the liner ports; and a motor and base assembly supporting the pump module, the first motor, and the second motor.
- 7. The apparatus of 6, further comprising a controller coupled to the first motor and the second motor during refill, discharge, and drawback modes to actuate:the displacement piston to expand the volume of the pumping chamber and the piston valve to rotate the fluid slot so the pumping chamber only communicates with an intake port, the displacement piston to reduce the volume of the pumping chamber and the piston valve to rotate the fluid slot so the pumping chamber only communicates with a discharge port, and the displacement piston to reduce the volume of the pumping chamber and the piston valve to rotate the fluid slot so the pumping chamber only communicates with a drawback port.
- 8. The apparatus of claim 6, wherein the first motor is coupled to a plurality of lead screws supported by the motor base assembly and disposed parallel to the pump module.
- 9. The apparatus of claim 8, further comprising a plurality of displacement slide blocks, each displacement slide block having a lead screw hole parallel to the pump module, a member joining the displacement slide blocks holding the pump module, and wherein each of the plurality of lead screw resides in a lead screw hole in one of the displacement slide blocks.
- 10. The apparatus of claim 8, wherein the first motor is coupled to a motor pulley, wherein each of the plurality of leads screws is coupled to a lead screw pulley, and wherein a belt couples the first motor pulley and each of the lead screw pulleys to drive the displacement piston back and forth.
- 11. The apparatus of claim 9, further comprising a plurality of linear bearing shafts, wherein each of the plurality of linear bearing shafts resides in a linear bearing shaft hole in one of the displacement slide blocks.
- 12. The apparatus of claim 6, wherein the second motor includes a ratchet-actuator assembly for rotating a cam actuator shaft forward or back and a ratchet assembly converting the forward or reverse rotation to forward rotation of the piston valve.
- 13. The apparatus of 12, wherein the ratchet-actuator assembly includes:a ratchet, in a housing, having ratchet teeth, a shaft, and supporting a roller clutch, an actuator shaft with a cam, and a pawl biased to engage the ratchet teeth, wherein the rotation of the cam raises and lowers the pawl with respect to the ratchet teeth, wherein each ratchet tooth catches on the pawl.
- 14. A ratchet-actuator assembly, comprising:a ratchet, in a housing, having ratchet teeth, a shaft, and supporting a roller clutch; an actuator shaft with a cam and camshaft; a pawl biased to engage the ratchet teeth; and wherein the actuator shaft rotates the cam back and forth so as to engage and disengage the pawl with respect to the ratchet teeth and the camshaft engages the roller clutch to rotate the ratchet forward.
- 15. A ratchet-actuator assembly, comprising:an actuator shaft with a cam and camshaft; an actuator for rotating the actuator shaft back and forth; and a ratchet with one or more teeth, a housing, a shaft, a pawl, a spring, and a roller clutch, wherein the housing rotatably supports the ratchet, the pawl, and the spring to bias the pawl against the ratchet, wherein the ratchet supports the roller clutch to engage and disengage the camshaft depending on the direction of rotation of the camshaft and the pawl selectively engages the teeth depending on the position of the cam with respect to the pawl.
- 16. The ratchet-actuator assembly of claim 15, wherein the actuator is a pneumatic actuator, including a vane blade extending from a vane shaft and directing pressurized gas for rotation of a vane shaft back and forth.
- 17. A ratchet-actuator assembly comprising:an actuator for rotating an actuator shaft; a cam and camshaft extending from the actuator shaft; and a ratchet extending from a ratchet shaft, wherein the actuator shaft rotates back and forth causing the cam to lower or lift a pawl to engage or disengage a ratchet tooth and a roller clutch transfers forward rotation of the camshaft to the ratchet when the pawl is not engaged with the ratchet tooth.
Parent Case Info
This application is a continuation-in-part of application Ser. No. 09/360,851, filed Jul. 24, 1999, which is incorporated herein by reference.
US Referenced Citations (4)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/360851 |
Jul 1999 |
US |
Child |
09/522249 |
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US |