US2266297A - Fuel pump - Google Patents

Description

Dec. 16, 41941.

A. M. BABITCH ETAL FUEL PUMP Filed July 3, 1939 2 Sheets-Sheet 1 qa' Gttornegs Dec. 16, 1941. A. M. BABlTcH E-rAL FUEL PUMP Filled July 3, 1959 2 Sheets-Sheet 2 Patented Dec. 16, 1941 2,266,291 FUEL PUMP Abraham M.

Flint, Mich., poration, Detroit, ware Babitch and Gordon W. Harry, assignors to General Motors Cor- Mich., a corporation of Dela- Application July 3, 1939, Serial No. 282,707

4 Claims.

This invention relates to pumps and has been designed to improve the pumps which are used to supply fuel for internal combustion engines.

An object of the invention is to provide an improved operating mechanism.

Another object resides in an improved form of pulsator.

Other objects and advantages will be understood from the description which follows.

In the drawings:

Figure 1 is a vertical section through one embodiment.

Figure 2 is a vertical section at right angles to that shown by Figure l.

Figure 3 is a top plan view partly broken away and in section.

Figure 4 is a, vertical section through the upper part of the modified form.

Figure 5 is a vertical section through the upper part of another modification.

Figure 6 is `a horizontal section through the modification shown in Figure 5.

Figure 7 is a vertical section of a modified form of operating mechanism.

In the form of invention shown by Figures 1 to 3, numeral II is used to designate a housing for the operating mechanism. `Numeral I3 is the body member of the pump and I5 is a cap. Bolts |1 secure these parts together. The main diaphragm marked I9 is clamped between lthe housing II and the body I3. A second diaphragm 2| constituting a part of a pulsator is clamped between body I3 and cap I5. Housing is closed by a cover 23 secured by screws 25.

The body I3 at its top has a circular ledge 21 forming a space 29 beneath diaphragm 2|. The body I3 has a lower circular ledge 3| forming a space 33 above the diaphragm I9. As shown by Figure 3 the body I3 beneath the space 29 is formed into two arcuate chambers 35 and 31 which are open to space -29. The two chambers 35 and 31 are separated by a transverse partition. This partition includes a circular dome 39 closed at its top and open to the space 33, an inlet passage 45 extending somewhat radially and a similar and slightly offset outlet passage 41.

A flange 53 seats against the body over the inlet passage 45 and holds in position an inlet valve designated by numeral 55. This valve controls a passage of fuel from a source of supply to the fuel pumpclramber 3 3. A second-ange 51 is secured to the body over the outlet passage 41. It houses an outlet valve 59. Just beyond valve 59, flange 51 is formed with a passage 6| registering with a passage 63 in the body, passage opening is a shaft 1| having a projecting driving end 13.

At the other end of this shaft and Within the housing is an eccentric pin 15. Rotatable on pin 15 isy the eye 11 of a link 19. A second link 8| is rotatably associated with link 19 by a connecting pin 83. Links 19 and 8| have arms 85 and 81 respectively and a coil spring 89 is connected to these arms. In pulling the arms together the spring brings into contact faces 9| and 93 on the links and dov so before the links reach alignment. A retaining links 95 is pivoted to the housing at 91 and its other end is pivoted to link 8| by pin 99. Pin 99 is also connected to the lower forked end of a stem |0I. The stem has a neck |03 and a head |05. The head and the neck are projected through a rectangular aperture of a plate |01. Thereafter the stem |0| is rotated about its axis through 90 degrees to lock the stem and plate |01 from separation. This construction will be understood by comparing Figure 1 and Figure 2. Above and below the diaphragm are reinforcing plates |09. The two plates, the diaphragm, and the plate |01 are secured together by fastening means The pump may be located in a'ny position where driving means is available for rotating shaft 1|. The eccentric pin operates through the instrumentality of links 19 and 8| and the stem |0I to reciprocate the diaphragm. Fuel is drawn into the pump chamber through valve in response to the suction stroke of the pump and it is forcibly ejected through valve 59 by the discharge stroke. Uniform discharge is made possible by the pulsator, the pulsator including chambers 35, 31 and 29 together with the diaphragm 2| backed by the` air cushion between the diaphragm and the cap I5. Spring 89 biases the linkage to that position where faces 9| and 93 are in contact with the result that as long as this contact is made, full strokes both of suction and discharge occur. The discharge stroke may be resisted by built up pressure at the pump outlet due to the closure valve in the carburetor. When this outlet pressure is sufficient to overcome spring 89, the spring yields and a collapse of Ilinks 19 and 8| occurs. It will be observed that since the spring is connected only to the links and has no contact 63 55 with@ fixed abutment its force is applied wholly to the diaphragm and it oiers no resistance to the suction stroke merely opposing resistance to the discharge stroke to the extent of the built up pressure at the pump outlet valve. The force required to operate the pump is therefore reduced to a minimum owing to the noating support of the spring.

Figure 4 shows.a modification in which the body I3 has inlet and outlet ports substantially as before. The body has a depressed region |02, the space around this region being a part of the pump chamber. Above the body is a member |04 having an intermediate partition |06. A diaphragm |08 is preferably clamped between the circular margins of the body member and member |04. In advance of the outlet valve the body is formed with a passage H2 communicating with a passage ||4 in member |04 leading to the space between the diaphragm |08 and the partition |06, this spa-ce serving as a pulsator for the outlet valve. To provide a pulsator for the inlet valve there is a second diaphragm ||6 located between the top of member |04 and a cap ||8. 'I'he space between the partition |06 and the diaphragm ||6 is in communication by suitable passages in the member |04 and the body member with that side of the inlet valve remote from the pump chamber. struction a pulsator effect is provided for both the inlet and discharge of fuel.

The modification by which a double pulsator may be provided with but a single pulsator diaphragm is shown in Figures and 6. In these gures a body 20| and cap 203 clamp between them a diaphragm 205. The body and cap have transverse partitions 201 and 209 registering with each other whereby two chambers 2|| and 2| 3 are formed. The chamber 2|3 communicates by means of passages 2|5 and 2I1 in the body and the valve carried ange 2|9 with the region beyond the outlet valve. Chamber 2|| is similarly associated with the space on the side of the inlet valve remote from the pump chamber. Suitable means 2 I0 secure to them the cap and the body.

For some purposes the operating arrangement shown in Figure 7 may be used. In this form a stem 30| is connected to a diaphragm, not shown, and corresponds with the stem |0| of Figure 1. Links 305 and 301 connected together at 309 are terminally connected at 3|| to the stem 30| and to an eccentric 3|3 on a rotary shaft 3|4. A guide link 3|5 is connected to pin 3|| and to By this conspring 323.

a pin 3|'| carried by the housing. Link 301 has a specially formed surface 3|9 to engage a pin 32| in link 305 and thereby prevents alignment of the links. A spring 323 is hooked to pin 30B and to a plug 320 adjustably held within a tubular member 325 threaded into the housing. A nut 326 threaded on the plug and engaging the end of tubular member 325 provides adjustment for the spring. In this form of the invention the surface 3|9 of link 301 normally engages the pin 32| of link 305 under the influence of the This relation of links 305 and 301 prevails at all times except when the outlet pressure of the pump overcomes the tension of the spring 323 at which times during the discharge movement of the eccentric the linkage collapses.

We claim:

1. In a pump, a movable pumping member having a stem, a rotary driving member having a part movable therewith in response to rotation of said member to extreme positions substantially in the axis of said stem, links jointed together and to said stem and part, a floating spring connected to said links, cooperating members on said links adapted to engage and to prevent link alignment under the inuence of said spring.

2. In a pump, a movable pumping member having a stem, a driving member having a part adapted to move toward and away from said stem, links jointed together and to said stem and part, a oating spring' connected to said links, cooperating members on said links adapted to engage and to prevent link alignment under the inuence of said spring, said pump including a housing and a guiding link terminally pivoted to said housing and to said stem.

3. 'Ihe invention dened by claim 1, said jointed links having arms and said spring terminally attached to said arms.

4. In a pump, a movable pumping member having a stem, a driving shaft having an eccentric pin, said pin adapted to assume extreme positions substantially in the axis of said stem in response to rotation of said shaft, links jointed together at their adjacent ends and terminally pivoted to said stem and pin, a floating spring connected to said links, and cooperating members on said links adapted to engage and to prevent link alignment under the influence of said spring.

ABRAHAM M. BABITCH. GORDON W. HARRY.

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