US3421448A

US3421448A - Fluid pressure actuated reciprocable pump

Info

Publication number: US3421448A
Application number: US608542A
Authority: US
Inventors: Lee M Brewer; John F Yonker
Original assignee: General Motors Corp
Current assignee: Motors Liquidation Co
Priority date: 1967-01-11
Filing date: 1967-01-11
Publication date: 1969-01-14
Anticipated expiration: 1986-01-14

Description

Jan. 14, 1969 M. BREWER ET AL 3,421,448

FLUID PRESSURE ACTUATED RECIPROCABLE PUMP Filed aan. 11, 1967 BY zz f 022/56? United States Patent Office Patented Jan. 14, 1969 7 Claims ABSTRACT F THE DISCLOSURE This invention relates to pumps and more particularly to reciprocable fluid pressure actuated pumps operable by secondary fluid under the control of a spring and magnet operated valve means.

Summary 0f the invention The reciprocable pump herein discl-osed comprises a one-way ow head in which the pressure of a primary iluid as secured from a supply source may be changed and a reciprocating pumping arrangement operable by a secondary fluid under the control of spring and magnet operated valve means.

Drawings showing the invention In the drawings:

FIGURE 1 is an elevational view of a fuel pump with portions broken away and showing parts .as positioned during a pumping stroke; and

FIGURE 2 is a view similar to that of FIGURE 1 but showing parts as positioned during a suction stroke.

Description A one-way flow head for a pump is disclosed in the U.S. Patent 2,868,135 granted Jan. 13, 1959 in the name of D. R. Reinertson and entitled Fuel Pump with Pulsator. Such a head is depicted at in the above described drawing. The head 10 includes an inlet 12 and an outlet 14 for a primary fluid such .as gasoline and also an inlet cham- -ber 16 and an outlet chamber 18 for that tluid. The chambers 16 `and 18 are separated by a partition 20 and conventional inlet and

outlet valves

22 and 24 are provided for pressure operation to give one direction flow from the `chamber 16 and subsequently into the chamber 18. The head 10 bears flange 26 by means of which fastenings such as the bolts 28 are employed tightly to hold the head to a drive casing 30 with a gasket 32 interposed. The casing includes a valve cap 34 flanged at 36 for retention -by the bolts 28 with the peripheral margin of a rolling diaphragm 38 interposed. An air chamber or secondary fluid chamber 40 is defined by the valve cap 34 and the diaphragm 38.

The casing 30 surrounds a pumping chamber 42 which extends from the diaphragm 38 to the bottom wall 44 of the ow head 10. The bottom wall 44 ha-s two

ports

46 and 48 controlled by the one-

way valves

22 and 24 respectively.

An annular portion of the rolling type diaphragm 38 is retained between the bottom of a cup 50` and an annulus 52 'by means of screws 54. A coiled spring 53 is compressed between the head bottom wall 44 and the bottom of the cup 50. The wall 44 is recessed at 55 freely to receive the upper rim of the cup 50. A raised portion 56 of the cup 50 is threadedly attached Ias at 58 to one end of a shaft 60, The other end of the shaft 60 bears an upwardly facing shoulder 62 and is slidable in a brass sleeve 64 which has a shoulder 66 facing the shoulders 62 and cooperating therewith to retain a coil spring 68 surrounding the shaft. The sleeve 64 is slidable in an upturned wall of an inverted cup 70. The latter bears a flange 72 held to the cap 34 by `a plate 74 and screws 76. The cup and the plate 74 each bears apertures such as at 78 and 80 respectively.

The brass or nonmagnetic sleeve 64 is reduced in diameter at its upper portion slightly to receive an annular magnet 82. The magnet is a drive tit on the sleeve so that the magnet is permanently held against a shoulder 84 on the sleeve to form a two-piece unit.

A nipple 86 is arranged to serve as an inlet for a secondary fluid or air under pressure passing to the secondary chamber 40 and if the magnet 82 is not in its lowest position, air from the chamber 40 will exhaust through the apertures 80.

In operation, pressurized air admitted at 86 will raise the rolling type diaphragm 38 against the spring 53. Primary tluid or gasoline in the pumping chamber 42 will be forced out by way of the valve 24, the -chamber 18 and the outlet 14 and in accordance with the pressure 'as provided by Way of the inlet nipple 86. At this time, and as depicted in FIGURE l, the aperture-s 180 .will .be closed by the air pressure acting on the magnet 82 and also by virtue of magnetic 'attraction of the latter to the plate 74. As the spring 53 is compressed the smaller spring 68 will also be compressed. When the small spring 68 is compressed to a desired and predetermined amount, it will overcome the forces holding the magnet 82 to its seat on the plate 74. This will shift the valve to its open position, i.e. the spring 68 will move the magnet 82 away from the plate 74 and toward the upper wall of the cup 70 permitting air or the secondary fluid to escape through the apertures 80. The return spring 53 is then effective to push the pumping diaphragm 38 downwardly and to draw more primary uid into the pump by way of inlet 12, the chamber 16 and the valve 22 to effect a suction stroke. When the cup 50 reaches the end of its suction stroke travel, it contacts the upper end of the sleeve 64 and moves the magnet 82 away from its upper position to its low position to close the ports 80 again to start the pumping cycle. Magnetic attraction between the magnet 82 and the plate 74 assures a quick closing of the valve.

Insofar as the present invention is concerned the ow head 10 could take any form, the patent mentioned being only exemplary in this respect. The rolling diaphragm 38 may be replaced by a piston as the pumping means although the diaphragm is preferred particularly in small pumps. The telescopic relation of the sleeve 64 and the shaft 60 with the spring 68 interposed constitutes a lost motion connection enabling the rolling diaphragm to move or remain motionless depending upon the pressure of or demands for the primary fluid in the discharge line or outlet 14. The discharge pressure, of course, depends upon the ratings of the springs 53 and 68 which will be determined in accordance with the particular use. It will be appreciated that the areas of the holes 78 and y80 as well as of the inlet in the nipple 86 mu-st be such that .air can be exhausted through the

holes

78 and 80 on the spring downstroke of the diaphragm 38 at a faster rate than it can come in inlet 86. This being the case, back pressure will not re-stain the downstroke.

We claim:

1. A pump comprising a How head and a drive casing, said flow head having one way pressure actuated Valves for controlling the flow of a primary fluid through the pump, a reciprocable pumping means in said casing and dividing the interior of the latter into a pumping chamber for said primary fluid in communication with said valves and a second chamber for a secondary fluid, valve means for controlling flow of said se-condary Huid through said second chamber, said valve means including an inlet and outlet port and a magnetic member serving to open and close the ports of said valve means, said magnetic member being interconnected to said pumping means to be `actuated thereby to open and close said valve means, and spring means in said casing urging the latter and said pumping means to move relatively.

2. A pump as set forth in claim 1, said valve means including a lost motion connection.

3. A pump as set forth in claim l, said spring lmeans in said casing being in said pumping chamber.

4. A pump as set forth inl claim 1, said recipr-ocable pumping means being al diaphragm.

5. A pump as set forth in claim 1, Said valve means being in a valve cap forming a portion of said casing, an inlet for said secondary fluid leading to a second chamber, and an outlet leading from' the latter and controlled by said valve means.

6. A pump as set forth in claim 1, an outlet from said second chamber, said valve means including a magnet movable With said pumping means to close and open said outlet, and an inlet to said secondary chamber for said secondary uid.

7. A pump comprising a ow head and a drive casing, said flow head having one Way pressure actuated valves for controlling the ow of a primary fluid through the pump, a reciprocable pumping means in said casing and dividing the interior of the latter into a pumping chamber for said primary fluid in communication with said valves and a second chamber for a secondary fluid, valve means for controlling ovv of said secondary tluid through said Second chamber, said valve means including a shaft having one end fixed to said pumping means to move therewith, a sleeve slideable in said casing and carrying Said magnetic means, spring means urging said shaft and sleeve in opposite directions, and a port connected to said second chamber and controlled by said valve means, magnetic means included in said valve means and connected to said pumping means'to be actuated thereby to open and close said `valve means, and spring means in said casing urging the latter and said pumping means to move relatively.

References Cited UNITED STATES PATENTS .2,221,071 11/1940 Barron 1034152 2,260,306 10/1941 Ferguson 10s-152 3,192,865 7/1965 Kiempay 103-152 3,294,030 12/1966 FOX 103-150 3,299,826 1/1967 Williams 10a-152 ROBERT M. WALKER, Primary Examiner.