US2131228A

US2131228A - Fuel injection pump

Info

Publication number: US2131228A
Application number: US95399A
Authority: US
Inventors: L Orange Rudolf
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-09-14
Filing date: 1936-08-11
Publication date: 1938-09-27
Anticipated expiration: 1955-09-27

Description

R. LORANGE FUEL INJECTION PUMP Sept. `27, 1938.

Original Filed Sept. 14, 1935 Patented Sept. 27, 1938 UNITED STATES Marzo FUEL INJECTION PUMP Rudolf Lrange, Stuttgart-Feuerbach, Germany Original application September 14, 1935, Serial No. 40,598. Diirided and this application Au;-

gust 11, 1936, Serial No.

September 20,. 1934 1 Claim.v

This is a division from application Serial Number 40,598 of September 14,1935.

This invention relates to a fuel injection pump particularly for use with compression ignition and like engines and of the kind wherein a plunger with constant stroke operates within a barrel relative to which it is angularly displaced for regulating the effective stroke of the plunger, the regulation being obtained by the provisionv of helical edges which co-operate for relieving thev pump pressure at any suitable point of the delivery stroke according to the angular position of the plunger.

The object of the invention is to obtain a pump construction wherein the inlet stream of fuel can be readily separated from the relieving stream thereof without the employment of a hollow plunger, and the invention consists in this respect in the provision of a solid plunger having a helical relieving groove which is in constant communication, through a surrounding barrel, with a relief outlet in the pump casing, the inlet of said casing being in communication with the pump chamber through a port controlled by the plunger, and the relieving groove of the latter being adapted, in known manner, to enter, sooner or later according to the angular position of the plunger, into communication with a recess in the pump chamber for relieving the pump pressure through the relief outlet.

Fig. 1 of the accompanying drawing represents a vertical section of a pump constructed according to the invention, and

Fig. 2 is a vertical section of a modified form of the pump.

'Ihe pump comprises a casing B wherein a barrel L is rigidlyfitted as a guide fora solid pump plunger M. The casing B is provided with a fuel inlet A and with a relief outlet Y, and it has two internal, circumferential grooves I and I0 each forming, together with the barrel L, a passage for the fuel. 'I'he groove I communicates with the fuel inlet A and it also communicates, through a conduit I2 in the barrel L with a port situated in the pump chamber 4. This port is traversed by the upper end of the plunger M and is thus controlled by the latter. The groove I 0 communicates, through a duct I3, with the relief outlet Y, and it also communicates, through ducts 9, with an internal, circumferential groove 8- in the barrel L. The latter groove cooperates with the plunger M to form a passage which is in constant communication with a helical relieving groove 6 made in the plunger M. There is a recess 5 made in the wall forming the pump chamber l, and the 95,3991.. In Germany (CL 10S-41) relieving groove. 6' cam by angularV displace-- ment of the plunger M,be put intocommunicatiorr with the pump chamber through the recess 5 at different points of the delivery stroke of. the

plunger for relieving the pressure in the chamber 5 through the groove and through the relief. outlet. The volume of fuel delivered bythe pumpis regulatedin this manner'. As the plunger uncovers the inlet port, fuel is admitted into the pump chamber, and after the portl hasy been closed. by 10 the plunger during the delivery stroke. ofthe latter, fuel. will be forced. past a delivery valve D and through a delivery port J into thev engine cylinder until the relieving passages are opened..

As the relieving groove 6 enters into communica- 15 tion with the pump chamber, it traverses an edge 2 of the recess'` 5 which is substantially parallel to the edge of the groove.

In the modified. pump construction. shown in Fig. 2, an additional duct. K is' providedv through 20 which the pump chamber communicates with the relief outlet Y. This duct opens into the pump chamber through a port which is substantially' on a level with the. inlet port and which is opened.

and closed simultaneously with the latter. It 25 will therefore be seen that while the. ports are opened, the pump chamber will be flushed with fuel' passing directly from. the inlet and through the chamber' into the relief outlet. This ilow of liquid, which clears the. pump chamber of all air 30 bubbles, continues for about one-half or twothirds of the time occupied by the complete plunger stroke, according tothe construction of the operating cam.

The fuel is supplied in any suitable manner, for 35.

instance by means of a separate feed pump, and', it will be seen that in both. pump constructions a continuous passage is formed through which fuel, which is not forced through the delivery pipe, can

circulate from. and to a supply tank which. is in 40 oscillating lever I5 which bearsl by means of a 45 f cup-shaped thrust member S against the head I6 of the plunger. The return stroke ofthe plungerv is effected by a spring C which engages the plunger head inside the thrust member S.

The angular displacement of the plunger for 5o regulating the effective stroke of the pump, is 'effected through the medium of a rod D1 which is arranged at right anglesv to the plunger and slidably mounted in rigid bearings I'l for rectilinear movement. Each pump plunger of the engine is tted with an operating lever R which is suitably coupled to the rod D1, so that the rectilinear movement oi the rod will be transmitted to the plungers and converted in the latter to a rotary movement. Y

The casting. B which encloses the barrel L is detachably connected to a casing F which encloses the operating elements.

I claim:

A fuel injection pump of the character described comprising a casing having a fuel inlet and a relief outlet, a barrel' mounted in said casing provided on the one hand with a port` which communicates with said fuel inlet and on the other hand with an internal circumferential groove which communicates with said relief outlet, a solidpump plunger fitted snugly in said barrel and adapted to control said port, said plunger being formed with a helical relieving groove, means for reciprocating the plunger within the barrel, said means operative to maintain the relieving groove in constant communication with the barrel groove while moving the free end of the plunger across said port, a delivery valve closing the end of the b rrel and forming a pump chamber between it and the free end of the plunger, the barrel having in said pump chamber a recess adapted, during the delivery stroke of the plunger, to be thrown into communication with the relieving groove of the latter for relieving the pump pressure through the relief outlet, and means for imparting to the plunger an angular displacement in order to determine the point of the stroke at which the relief takes place, the barrel being provided with a duct which is closed by the plunger substantially at the same time as the inlet port and which communicates with the relief outlet for allowing free circulation of fuel through the pump chamber when the inlet port is opened.