US2036452A - Fuel pump - Google Patents

Description

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FUEL PUMP Filed Deo. 6, 1954 2 Sheets-Sheet 1 April?, 1936.. A M BAWCH EFM www FUL PUMP Filed Deo. 6, 1954 2 Sheets-Sheet 2 I l mw Il Mmmmun "uw Patented Apr. 7, 1936 PATENT OFFICE FUEL PUMP Abraham M. Babitch and Gordon W. Harry, Flint, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application December 6, 1934, Serial No. 756,257

4 Claims.

This invention relates to pumps and has been designed as an improved pump for supplying fuel from the fuel reservoir of a motor vehicle to the engine.

The object of the invention is to provide a pump having superior characteristics such as freedom from leakage, simplicity in the process of assembling the parts, and freedom from noise in operation.

Other objects and advantages will be understood from the following description.

In the illustrated embodiment shown in the drawings the fuel pump is associated with a vacuum booster pump intended particularly for sup-,- plementing the engine manifold in the operation of a suction motor of an accessory such as a windshield cleaner.

lin the drawings:

Fig. 1 is a vertical section through the com bined pump structure.

Fig. 2 is a section on line 2-2 of Fig. l.

Fig. 3 is a section on line 3-3 of Fig. 1.

Fig. l is a perspective of the fuel pump valve assembly and the retainer therefor, parts being shown in disassembled relation.

Fig. 5 is a plan view of the rocker arm and linlr assembly.

Referring by reference characters to the drawings, numeral lll is the upper of three casing members, these being preferably made by die casting. The member ll is recessed on its un.- derside at as i3. To its upper surface there is secured an inverted cup l5 which may be of glass and which is held against a gasket il by a conventional bail it. The top of the bail carries a screw 2l upon which is threaded a nut ttl, the latter engaging a cup-shaped stamping t5 in Contact with the glass cup l5 to hold it in position. Within the cup l5 and integral with the casing ll is a closed air dome 2l. The casing is also formed with a wall 29 merging with the wall of the air dome at spaced points marlied a and `b in Fig. 2. Between the spaced points a and b the wall 29 is spaced from the wall of the air dome 2l to form a pump inlet space or region 3l. The upper wall of member ll also has formed therein an arcuate sediment collecting recess 33. The upper part of the dome 2l together with the wall 29 is formed with a circular ledge 35 upon which is supported the lower and smaller edge of a funnel-shaped ring 3l to the top of which ring is secured a strainer il@ of wire cloth. A plurality of peripherally spaced fingers 4I extend from the top of ring 3l and engage the glass cup. The strainer assem- (Cl. 10S-150) bly is thus resiliently held in position. Leading into the space within the glass cup and communicating Withthe region outside the dome 2l and the wall 29 is a passage i3 extending through the Wall of casing ll as shown in Fig. 2. An inlet pipe from the fuelreservoir is to be secured to the entrance t3. From the region Within the dome 2l an outlet passage 45 extends through casing ll to the wall thereof as shown in Fig. 2. From the end of this passage a conduit is to be connected for communi.` cation with the carburetor of the engine.

It will now be understood that the recess i3 is the pump chamber, and that fuel enters it by way of passage 53,. through the screen 39 and then through space 3l. From the pump chamber the fuel passes into the dome 2l and out through passage 45. Controlling the en- .trance and exit are inlet and outlet valve assemblies. The inlet valve assembly, marked tl, is beneath the flared opening from space 3l leading to the pump chamber. The outlet valve assembly, marked 69, is in the communieating passage from the pump chamber to the dome. The two Valve assemblies, tl and t9, are identical in construction and are illustrated in Fig. l and Fig. 4. Each valve assembly consists of a disc valve 5l formed to engage a seat 53,- the seat being the smaller diameter part of an apertured ring 55. A stamping 5l has a circular edge 59 bent over and engaging the the outer face of ring 55. The stamping surrounds the outer periphery of ring and is inwardly bent to engage the opposite face of the larger diameter portion as shown at lil. 'Ihe stamping is then extended to form a ring portion t3. It is Within this ring portion that the disc valve 5l reciprocates to and from itsseat. The stamping then extends as shown by Fig. 4 to form an abutment for the spring 65 of the valve. Inlet valve assembly lll is positioned as shown by Fig. l and Fig. 4 with the face 59 engaging the casing wall around the passage between space 3l and the pump charnber. Outlet valve assembly Il!) is inverted so that the face tl engages the annular wall between the pump chamber and the dome 2l. A valve clamp or retainer 6l, shown in detail in Fig. 4, is provided with openings for the passage of suitable fastening means by which it may be secured to the underside of casing ll. This clamp has opposite arcuate arms ll and l3. Arm ll engages face 6| of Valve 'll and arm i3 engages face 59 of valve 49. By this expedient it is unnecessary to make separate "vate assemblies. .is single .cs in position. En this wey the cost et manu Lecture is reduced as is also the cost o' assembly and removal o the valves.

The intermediate pump casing ineinher is designated by numeral Fastening means clamp casing members il and together with the pump diapiu'agin tl'ierehetween. Casing member has an inner part il@ `with an apertured wall di through which the diaphragm stem extends with a small clearance. @Veritoing the wall Si is an oil seal disc @il formed from sott material such as rubberl or leather. lt is positioned by a retainer ill. lhe retainer has at its lower end a flange seated on the casing member. A spring @t engages the retainer at its lower end and a spring guide washer iii at its upper end. lt may be stated here that this spring ii@ is the instrumentality llor producing the discharge stroke oi' the pump. The guide washer lli is seated on shoulder of stem together with diaphragm protecting washers @3 and 95, the former beneath and the latter above the diaphragm llt. Above Washer there is press-litted on the stem. a Washer Sl. Washer @il has a central stepped portion at da. The assembly of dia phragm and Washers is then rigidly secured by riveting or spinning over the hollowed end oi rod. as shown by i. The recess in. Washer 9i' provided by the stepped construetion taires care of any copper shavings which may be produced when the Wher is pressiitted over the stern which is to be copper= plated. Since Washer is fitted on the stern fixed relationship exists between the position of the diaphragm and the :dat on its stern $3, which flat must be correctly positioned for engagement With operating mechanism as will he explained below.

Beneath intermediate casing l5 is a third casing member This third member is secured to casing 'it by' fastening means iti and a plirsgin iii@ is clamped between these casing members. A cap SUE is secured by Jasteni means lili to the bottoniL of casing il. s

ills is seated upon a suitable abutment trl casing @s and engages diaphragm peotecting Washer iii, the latr seing depressed centrally to position the spring as at UUS. Washer lili is secured to the phragrn and lower washer by rivets lil winch als scorre additional washer il@ h centrally disposed raised portion angular in outline at itt. Wltlun this angular raised portion is seated e. similarly shaped h E23 of stein t ln Way there is no possible leakage through diaphragin lull, and since no relative rotation can occur betwn the stem and the diaphragm fiat face on the stem l2@ for engagement *mth operating mechanism is definitely located by predetermined position of rotation of tl'ie dia ph s1-gn.. The lower casing has suitable inlet and outlet openings at itil, 62s. lt also has inn let and outlet valves, the latter oi which is shovm at iti Since it is old to associate such a second pump with a fuel pump and since no details of the second pump, in addition to those already described, constitute a part of this invention, it is unnecessary to further describe the second pump.

The operating means for the two pumps is located in the intermediate chamber llo and a portion of the operating means projects from 'iti into the engine casing when the casing; h clamped to the engine casing, provision for which is shown by openings G33 in the casing fange A pivot pin lill is press-fitted into casing and extends e/eross an opening flange A bushing it@ is journaled on the pin Journaled for rotation on the bushing is a rocker arm liti. One end o ann en tends into the path of movement of cam Mt within the engine casing. The other end oi rocher arm Mi is forked, its furcations Mii and Ml rotatably supported on the bushing i 3Q. Between the furcations M5 and Ml are the jour-- naled ends oi links M9 and Elli. Between these links and also journaled on the same bushing is lil a shorter linlr 53, A. U-shaped link spacer and spring seat is shown at it. The legs of this U-shaped spring seat are mounted for rotation on the bushing i239 and are located between linhs M9 and ll and straddle link. E53. Adjacent the bend of the U of member liiti and on the legs are locating lugs im. Cooperating with these lugs is a casing lug i553. The lugs on member W5 and on the casing position a spring Q66. This spring acts to push the member litt whereby it engages a surface E63 on the rocker arm illi between the furcations and thereby functions to keep the rocker arm in contact with the cam. The surface |63 is also adapted to engage the end surfaces of links M9, it, and itl@ .t and to swing said links. The engaging surfaces between the links and the rocker arm afford lost motion connections whereby the pumps may operate with variable strokes. The mecharucal mechanism involving the rocker arm and the links function to maire the suction stroke oi? the fuel pump and the discharge stroke o." the vacuum pump. The springs and im ser' e to the other strokes of the two pumps. "nlVm td@ and loi are brought into contact at extreme ends as shown in Fig. 5. The cnrs shaped into hooked form as may be seen l where they are extended through an onenT the liet portion t6@ ot stern. Mil. the hooked end itl oi' linh :lo interlocltci, 'lith the end it@ of stern @3. lin assembling` the parte it will seen t t the nots on the sten-'is must be positioned as shown, and dats have a fixed relationship to tl phragin in the case oi both pumps, nredetei positions' of the haphragms will insure coi..- rect relationship ot the stems with in is desirable that the hot oil should me from the crank". oase through the o1 into the pump casing provided ior sage oi the rocher arm. Such oil d the diaplu'agm and the oil loss serious. To that end a plate as shown in l'f'ig. 3 is placed over harige lift, its edge resting on in the casing as shown ln Fig. liti an opening Elli and the rocker aim lill .As sur faces ill and H9 snugly fitting the upper und lower walls of the seal opening as the onu rotates on its pivot. The side laces of the roc arm engage the side Walls oiP the opening llt. To secure the seal in position there are provided tenons li in the casing ilange. Adjacent these tenons the seal has apertured depressed regions os at Wfl. After the apertures are positioned to surround the tenons, the latter are staked over the seal to hold it as shown in Fig. 2. It will be seen that in the staking process the end of the tenon is not clamped against the seal. ln this Way slight movement o1' the seal is provided to accommodate any irregularity in the location of the rocker arm which snugly ilts the opening in the seal as explained above. Provision is made for the return of any oil which may enter the pump casing from the crank case. In the lower part of the casing ilange is a pocket within which any oil passing around the rocker arm may collect. A flap valve |81 of flexible material and secured to the seal |1| covers an opening |89 communicating with the crank case. This valve is secured by suitable fastening means 9| The oil may return to the crank case through this valve, but the valve closes against the passage of oil from the crank case.

Among the advantages resulting from the novel pump structure described above are the following: The screen is not clamped between covers as in many prior constructions. Leaking, which would aii'ect priming of the pump, is therefore avoided. The provisions to prevent rotation of the diaphragms relative to their stems is of help in assembling the parts because the stems must be located in predetermined positions of rotation to engage the links. The oil sealing devices for the fuel pump stem and for the passage between the crank case and pump casing effectively prevent damage to the diaphragms from heated oil within the crank case. A leak-proof assembly is provided for the connection between the vacuum pump diaphragm and its stem. The sliding contact between the parts rotating on the pivot pin bushing prevents nose. The novel valve assembly is of importance, particularly for purposes of assembly and replacement. Both valves are alike and assembly and replacement of both is simultaneously eiected by the attachment or removal of a simple retainer. The use of the bushing to take the load of the rocker arm and links prevents any loosening of the pivot pin in the casing.

We claim:

1. In a pump, a pump casing, a movable pumping member therein, an actuating lever journaled in said casing, projecting therefrom and operably connected to said movable member. sealing means carried by said casing and apertured for the passage oi said lever, said lever being shaped to continuously fit the aperture of said seal as it rotates, said sealing means being secured to said casing by means permitting slight movement thereof to accommodate irregularities in the position of said lever.

2. In a pump, a pump casing, a movable pumping member therein, an actuating lever journaled in said casing, projecting therefrom and operably connected to said movable member, sealing means carried by said casing and apertured for the passage of said lever, said lever being shaped to continuously ilt the aperture of said seal as it rotates, said seal having at its lower end an opening covered by a nap valve to permit passage of uid from within the pump casing.

3. In a pump, a pump casing, an actuating rocker arm journaled therein and projecting ABRAHAM M. BABITCH. GORDON W. HARRY.

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