US3022737A - Fuel pump - Google Patents

Description

Feb. 27, 1962 c. H. TUCKEY 3,022,737

FUEL PUMP Filed May 6, 1959 WAV/1471;,

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cfm/a4 fs ff. rackyfr BY A ATTORNEYS United States Patent Charles H. Tucirey, Sass tCity, Mich., assigner 'te Waihro Corporation, Cass City, Mich., a corporation or Michigan Filed May 6, i959, Ser. No. SlLil'! 2 Claims. (Cl. 10S-nda) This invention relates to a fuel pump and is particularly intended to be an improvement on cca-pending application, Serial No. 766,614, iled Gctober l0, 1958, new Patent No. 2,984,188.

It is an object of the present invention to provide a construction which is relatively simple and economical as far as the manufacture is concerned and one in which there are no mechanical parts which can wear out or become mechanically out of order.

Another object of the invention is the provision of a housing which adapts to a very simple valve construction for a fuel line pump.

Other objects and features of the invention relating to details of construction and operation will be apparent in the following description and claims.

Drawings accompany the disclosure and the various views thereof may be brieily described as:

FIGURE l, a sectional view showing the relationship of the parts of the pump.

FIGURE 2, a sectional view on line 22 of FIG. l.

FIGURE 3, a modied view of the construction showing the manner in which the housing can be used as a lilter.

Referring to 'the drawings, in FIGURE l, a main housing 10 has a side extension l?. tapped to receive a nipple connection la. Fl`he housing has a central bore forming an elongate chamber i6 and a concentric annular recess 1S around the central bore. At the bottom of the housing is a hose connector projection 2t) opening into the central bore 16. At the bottom of the central bore is a conical valve seat 22.

Disposed within the central bore is a sac diaphragm 24 having a radial, outwardly extending, sealing ilange 26 extending outwardly over the recess l. The closed end of the sac 24 contacts and seals the valve seat 22 as a unidirectional valve admitting fuel from a supply. The sac also divides elongate chamber le into a fuel re' ceiving chamber outside the sac and a 'pulsation pressure chamber inside the sac.

A cap 30 is pressed over a slight annular ridge 28 on to the open end of the housing liti and serves to clamp the sealing ange Z6 over the top of the housing. The cap 30 has a hollow hose connection 32 which is adapted to be connected to a source of pulsating pressure such as a crank case of a two-cycle engine or a manifold or a carburetor passage. The hollow projection Z serves as an inlet for a fuel supply and the nipple 14 serves as an outlet. In the wall between the bore 16 and the recess 18 is an opening 34 which is closed by a wide rubber band or cylinder 36. This hole 34 is aligned with a second hole 33 leading to the nipple lid.

in the operation, pulsating pressure in the main bore inside the sac 2li will cause the sac to enlarge and ensmall, thus reducing the pressure in passage lil and also causing the sac which contacts the valve seat 22 to refrom the valve seat. T his carries fuel into the bore l outside the sac 2d. Ile-expansion of the sac 24 again seals the valve seat 22 and forces liquid out through hole past the elastic band 36 into the outlet passage 38. rhere is thus provided an extremely simple pump construction which has no mechanical parts.

In FIGURE 3 a modified construction is shown using the same housing but using a closed cap Sil with an annular seal ring 52. The cap Sil has an annular recess 54 which receives one end of a cylindrical screen element Se, the other end of which bears against the bottom of bore le. Also in the cap is a depending magnetic element SS which projects into the area inside the screen 56. ln the operation of the device flow will enter the passage di), pass through the screen and out the openings 3dand 38. Any metal particles in the gas will be attracted to the magnetic element 5? to keep them out of nui.

the engine. The cap may be removed and the element 56 cleaned or replaced.

l claim:

l. A fuel pump for small engines to operate `from a source o pulsating pressure in the engine of the type having a housing with a pumping chamber, an inlet and an outlet to said opening, an inlet valve anda diaphragm Within said chamber, that improvement which comprises a means forming an annular chamber around said pumping chamber, a passage through the Wall of said pumping chamber connecting to said annular chamber, said annular chamber being connected with the outlet of said pump, and an outlet valve comprising a band of resilient mate# rial positioned snugly around the inner walls of the annular chamber overlying the connection with said pumping chamber, said material permitting ilow outward from said pumping chamber into said annular chamber and blocking ilow in a reverse direction.

2. A pumping device as defined in claim 1 in which the pumping chamber and the annular chamber are opened at one end of the housing, and means closing the open ends of said chambers at said end of said housing for connecting said pumping velement to a source of pulsating pressure.

References Cited in the tile of this patent UNITED STATES PATENTS 1,503,279 NiXOn July 29, 1924 2,920,573 Schaurte Ian. l2, 1960 FOREIGN PATENTS 79,747 Netherlands Nov. 15, 1955 257,519 Italy Mar. 7, 1928

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