The present invention relates to a flexible tube pump, and more particularly to a pump with a magnetically collapsible elastomeric member which collapses over a mandrel.
Reciprocating pumps are highly desirable for use in numerous applications, particularly in environments where liquid flow rate is relatively low and the required liquid pressure rise is relatively high. For applications requiring less pressure rise and greater flow rate, single stage centrifugal pumps are favored because of their simplicity, low cost, and low maintenance requirements.
Another pump type is a flexible tube pump. Such pumps are often used for the transportation and pressurization of sensitive media or for applications in the vacuum field where the achievement of a “Clean” vacuum is relatively important. Common forms of pumps with a flexible member are bellows and diaphragm pumps. The diaphragm is typically an elastomer forming part of the volume being pumped. By reciprocating the flexible member within the pump head space in which are usually located inlet and outlet one-way valves, the media being pumped enters and is then forced out of the pump head. The mechanism for actuating the flexible member may be by linkage to a motor or by valved compressed air.
Other actuators include a magnetically responsive elastic tube stretched onto, thereby sealing to, a shaft with inlet and outlet ports at or adjacent tube ends. Local to the inlet port a magnetic field is generated within the enclosing body. This field is substantially concentric to the tube, which responds by expanding circumferentially towards the magnetic field. This creates a volume between the tube and shaft, the length of the tube outside the influence of the magnetic field remains sealed upon the shaft. Subsequent movement of the magnetic field along the axis of the pump gives transport to the volume and any media enclosed within from the inlet port to the outlet port, whereupon reduction of the magnetic field results in exhaustion of the volume. This cycle results in a pumping action.
Disadvantageously, known flexible tube pumps are complicated, relatively costly to manufacture and provide minimal pumping pressure.
Accordingly, it is desirable to provide an inexpensive flexible tube pump which provides increased pressures.
The magnetic pump system according to the present invention includes a ring shaped electric magnet that when pulsed with high voltage and high current, causes an magnetically deflectable elastic member to collapse over a mandrill with an arcuate outer surface. The volume between the arcuate outer surface and the inside of the elastic member is reduced causing compression and expulsion of the fluid therein through a one-way passage system. When the magnetic field subsides, the tube regains its shape drawing fluid in through the one-way passage system.
When the magnet is energized, an intense magnetic field is created. If the elastic member is conductive, eddy currents are generated on the elastic member. This creates a magnetic field that is opposite to the ring magnet field. The two fields repel each other and since the elastic member is elastic it moves towards the mandrill. If the elastic member is magnetic, the fields of the magnet and the ring magnet repel each other and the same action occurs.
The present invention therefore provides an inexpensive flexible tube pump which provides increased pressures.
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
a is a schematic top view of a single bitter disc in which a multiple thereof forms a magnet for use with the present invention;
b is a schematic top view of a magnetic bitter disc showing contact which allows a multiple of stacked bitter discs to form a helical magnetic coil;
c is a schematic top view of a bitter disc showing contact areas which allows a multiple of stacked bitter discs to form a helical magnetic coil;
d is a schematic bottom view of a bitter disc showing a contact area which allow a multiple of stacked bitter discs to form a helical magnetic coil;
The mandrill 12 defines a longitudinal axis A. The mandrill 12 is a generally tubular member with an arcuate outer surface 17 defined about the axis A to form a generally hour-glass shape. More preferably, the outer surface 17 is parabolic. A passage system 18 (
Referring to
Each passage 18a-18c of the passage system 18 includes a one-way check valve 28 such that fluid will only flow from inlet port 20 to the discharge port 22. Each passage is essentially segmented into an input portion, which feeds into volume V, and a discharge portion which feeds from the volume V. The input and discharge portions need not be linearly aligned. Each check valve 28 is preferably threaded into the inner diameter of the passages 18a-18c, however, other mounting arrangements may also be utilized.
The magnetically deflectable elastic member 14 is preferably a tubular rubber material impregnated with conductor or magnetic materials. Alternately, flexible electrically conductive strips such as copper plated spring steel strips or wires are mounted around the tube.
The deflectable elastic member 14 is mounted to the mandrill 12 adjacent each manifold 24, 26 through an annular clamp ring 30. The clamp ring 30 includes a wedge shape 32 which corresponds to a mandrill wedge shape section 34 along each rim 36 thereof. The clamp ring 30 is attached to the mandrill 12 though fasteners F (also illustrated in
The ring magnet 16 is preferably a ring magnet which generates a field that is parabolic in shape (
Referring to
Each bitter disc 38 is rotated relative to the adjacent disc so that each contact area C on one side of a bitter disc 38 contacts the contact area C2 on an opposite side of the adjacent bitter disc 38. That is, the contact areas C1, C2 on a single bitter disc are radially displaced and on opposite sides of each bitter disc 38. By radially displacing each adjacent bitter disc 38 in a stack (
Referring to
This control circuit 44 is preferably a single phase supply, however, a poly-phase supply may be used by replacing the transformer and bridge with a poly-phase transformer and bridge. Depending on the incoming voltage and desired DC voltage the transformer may not be required. For example, if the incoming power is 480V AC the DC voltage will be about 700V. If the switches are designed to handle these voltages no transformer would be required.
The control sequence of operation is generally as follows: 1) initially AC and DC switches are open; 2) the AC switch is closed and the capacitor charged for time T1; 3) the AC switch is opened; 4) the DC switch is closed discharging the capacitor into the ring magnet; and 5) the DC switch is opened for time T2.
Each time this sequence is executed the ring magnet 16 fires and collapses the deflectable elastic member 14 (
One magnet has been illustrated for simplicity of explanation, however, multiple magnets are preferably utilized to produce a greater flow velocity. The magnets are fired in sequence from inlet port to discharge port. The advantage is that as one magnet is firing the firing circuit of the others can be charging. Notably, the deflectable elastic member may extend beyond the inlet and discharge such that if the deflectable elastic member is extended from the inlet to the source and from the discharge to the destination a totally lead free system is achieved.
It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting.
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present invention.
The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.