US2239884A

US2239884A - Variable push rod for diesel

Info

Publication number: US2239884A
Authority: US
Publication date: 1941-04-29
Anticipated expiration: 1958-04-29

Description

Patented A rize, 1 941 UNITED STATES PATENT OFFICE VARIABLE PUSH ROD FOR DIESEL INJECTORS Lawrence J. Deeley, Blossvale, N. Y. v Application April 23, 1940, Serial No. 331,250 7 Claims. (Cl. 103-38) My invention relates broadly to fuel pump units for internal combustion engines, and more particularly to variable push rod assemblies for the pump units.

An important object of my invention is to provide a push rod assembly wherein the connection between the push rod and the pump plunger is unique to permit the stroke of the plunger to be manually controlled to efiectively regulate the quantity of fuel supplied to the engine cylinder.

Another object of my invention is to provide a push rod assembly of the above-mentioned character wherein the fuel injecting stroke of the pump plunger is started at the same position of the engine piston for every operation thereof regardless of the adjustment of the assembly to regulate the distance that the plunger is set to travel, thereby assuring proper timing of the fuel injected into the engine cylinders for'every speed of the engine.

Still another object of my invention is to provide a push rod assembly of the above-mentioned character that is simple in its construction, inexpensive to manufacture and efficient and eflicacious in the performance of its duties.

Other objects and advantages of my invention, will be apparent during the course of the following description.

In the drawingforming a part of this specificatiomand wherein like numerals are employed to designate like parts throughout the same,

Figure 1 is a top plan view of a four-cylinder push rod assembly unit,

Figure 2 is a vertical sectional view of one of the push rod assemblies,

Figure 3 is a transverse sectional view taken on the line 3-3 of Figure 2,

' Figure 4 is a fragmentary transverse sectional view taken on the line 4-4 of Figure 2, and

Figure 5 is a fragmentary perspective view of a longitudinal section of the casing.

In the. accompanying drawing, wherein for the purpose of illustration, is shown a preferred embodiment of my invention, the numeral l designates a guide block which comprises a laterally extending integral part of the engine having a channel I I in its outer vertical face, the side walls of which channels are grooved, as atl2, to receive the ribs I3 of the support M.

The support is adapted to carry a plurality of laterally spaced push rod assemblies l and each of the assemblies is adapted to be connected to a fuel pump for separately injecting fuel into the cylinders of the engine. Each of the push rod assemblies is identical in its construction and operation and a detailed description of but one will, therefore, be given.

A guide plate l5 extends forwardly of the block 10 below the support [4 and the square'portion l6 of the push rod I1 is snugly but slidably accommodated within the essentially square opening l8. The opening I3 is arranged directly above the cam shaft 2| of the engine and the lower end IQ of the push rod contacts the cam 20. pressed engagement with the periphery of the cam by the coil spring-22 which is interposed between the bottom face of the guide plate and a spring seat 23 carried by the lower end of the rod. The upper end 24 of the push rod extends a substantial distance above the guide and in axial alignment with the internal bore 25 of the casing 26 fixedly secured to the face 21 of the support by the bolts 28.

A pump plunger 29 is interposed between the pumpbarrel 30 and the casing, the upper end of the plunger being formed with an enlarged head portion 3| arranged to reciprocate within the bore 32 of the barrel and the lower end thereof being formed with an enlarged axially extending sleeve 33 reciprocally received within the bore 25 of the casing. The sleeve 33 is pro-, vided with laterally extending trunnions 34 which normally travel in longitudinally extending grooves 35 provided at opposite sides of the bore.

The grooves terminate adjacent the upper end of the bore 25 in an annular groove 31, said groove defining shoulders 36 which engage the trunnions to limit the upward movement of the plunger relative to the casing. The lower ends of the grooves 35 open directly through the bottom face of the casing and the upper ends thereof open directly into the annular groove 31.

The internal bore 38 of the sleeve 33 is provided with a helical track or thread 33 which receives the thread formed on the upper end 24 of the push rod and, as clearly illustrated in Figure 2, the interfitting threads 39 and 40 of the push rod and pump plunger have an essentially steep pitch. The threaded end of the push rod may be entirely accommodated by the bore 38, however, it is limited in the distance which it may be retracted therefrom to substantially the position as shown in Figure 2. It may thus be seen that the relation of the push rod with the pump plunger is fixed at all times, but that the push rod may be advanced into or retracted from the bore 38 to substantially vary the combined length of the' plunger and push rod.

The outer face 21 of the support is formed with The rod is at all times yieldably held in nular groove disposed adjacent the upper end of the bore, the saidplunger being normally held in fixed association with the push rod by engagement of the trunnions within the longitudinal grooves but adapted to rotate relative thereto upon move open into an annular groove disposed-adjacent the upper end of the bore,a reciprocally actuated push rod arranged below the pasmg'am having I an end screw-threadedly received by* a recess opening through the lower e'ndof the plunger, the said plunger being normally held in fixed association with the push rod by engagement of the trunnions within the longitudinal grooves but adapted to rotate relative thereto upon movement of the trunnions into register with the said annular groove, and means independent of the above-mentioned parts to move the casing axially of the said plunger.

6. A fuel pump having in combination, a supporting member, a tubular casing carried by the said member, a plunger having trunnions adapted to travel in longitudinal grooves provided in the the upper end of the bore, an actuator means connected to the said support in a manner to move the support and easing axially of the plunger, and a reciprocally actuated push rod arranged below the casing and having an end screwthreadedly received by a recess opening through the lower end of the plunger, the said plunger being normally held against rotation on the push rod by engagement of the trunnions within the longitudinal grooves of the casing but being adapted to rotate relative thereto upon move ment of the trunnions into register with the annular groove.

.7. A fuel pump having in combination, a supporting member, a tubular casing carried by the said member, a plunger having trunnions adapted to travel in longitudinal grooves provided in the bore of the casing which longitudinal grooves open into an annular groove disposed adjacent the upper end of the bore, an actuator means .associated with the said support in a manner to move the support and easing axially of the plunger, a reciprocally actuated .push rod arranged below the casing and having an end screw-threadedly received by a recess opening through the lower end of the plunger, and means to reciprocally actuate the said push rod, the said plunger being normally held against rotation on the push rod by engagement of the trunnions within the longitudinal grooves of the casing but being adapted to rotate relative thereto upon movement of the trunnions\into register with the annular grooves.

LAWRENCE J. DEELEY.

n a R R E J a Apr-5129,, E941 CUTTING AND WELDING TORCH Filed Aug. 22., l