US2018975A - Fuel pump for diesel engines - Google Patents

Description

Oct. 29, 1935. E. SCHUTZNIEDRIG FUEDPUMP FR DIESEL ENGINES Filed Jan. 30, l935 38heets-Sheet l INVENTOR WALD SCHl/7IZN/EDE/G.

ATTORNEYS Oct. 29, 1935.

E. SCHUTZN1EDRIG FUEL PUMP FOR DIESEL ENGINES Filed Jan. 30, 1955 5 Sheecs-Shee 2 INVENTOR WALO SCHUTZNIEOE/G &

Oct. 29, 1935. 1 E. SCHUTZNIEDRIG 25013975 FUEL PUMP FOR DIESEL ENGINES Filed Jan. 30, 1935 5 Sheets-She et 3 ATTO RN EY Patentecl Oct. 29, 1935 UNITED STATES PATENT OFFICE FUEL PU1\IP FOR DIESEL ENGINES Ewald Schutzniedrig, Detroit, Mich.,. Victor A. Koch, Detroit,

signor to Mlh.

Application January 30, 1933, Sofia] N0. 654,145 6 Claims. (C1. 103-38) The present invention relates to a novel fuel supply pump mechanism of a type particularly adapted for use in combination with internal combustion engines of the type that use heavy oil as fuel, and more particularly in combination chambers into which heavy oil is injected through nozzles, sufiiciznt pressure being exerted by the present pumping mechanism to eject the oil from the nozzles in the form of a fine spray.

Another object of the present invention is to provide means for supplying fuel to, and for varying and controlling the rate of fuel ejection from nozzles associated with the combu.stion chambers in an interial combustion engine of the type using heavy oil as fuel.

Another object cf the present invention is 120 provide a fuel pumping mechanism including a plurality of pumping units corresponding in number to the cylinders any given internal combustion engine of the Diesel type, each of.the pumping units comprising a, chamber and a pumping element therein, the chambers of the difierent units being in communica.tion with a common supply source and the comp1essing elements being constructed in two resiliently associated parts that facilitate adjustment in a manner to vary the amount of fuel pumped by the present pumping mechanism at any given speed of operation. The resiliently associated fuel impelling or pumping members may be adjusted manually to vary the amount 01 fuel pumped and accordingly vary the speed of the engineto which it supplies the fuel.

With the above and other ends in view the invention consists in mattem hereinafter set forth and. more particularly pointed out in the appended claims, reference being had to the accompanying drawings, in Which Flgure 1 is an end view or elevation of a. Diese] pumping mechanism th rewith;

' engine illustrating the agsociation o; the present Fig'. 2 is a, detail sect on cf a nozzle; Fig. 3 is a transyerse crpss section 01 the pumping mechanism;

Fig. 4 is a cross section taken along the line l4 o1 Figure 3;

Fig. 5 is a plan view of the pumping device with the cover thereof removed, and

Fig. 6 is a. plan section taken along the line 66 of Figure 3.

Like characters of reference are einployed throughout to designate corresponding parts.

In Figure 1 of the drawings thereis shown an engine of the double opposed type, having cylindrs arranged at an angle relative to each other and one above the other in horizontally extending banks. It is to be understood, however, that the particular engine shown is for illuS- 10 trative purposes only and. tha.t the present pumping mechanism may be employed to supply fuel to any internal combustion engine using heavy oil for that purpose.

The engine comprises cylinder blocks I having 10 drilled therein the upper and lower banks of cyl-. inders, pistons 2 being received in the cylinders. Valve heads 3 a're bolted to the ends of the cy1- inder blocks I and each head forms a, combustion chamber 4. In the valve heads 3 are mounted nozzles 5 to communicate with combustion chambers 4, the nozzles being shown in detail in Figure 2 on a larger scale. The motor also includes a pair of crank shafts 6 and 1 that are connected to their associated pistons by rods 8. Exhaust valves 9 are provided and are operated by cam shafts I0 that are driven through shafts I I and gearing I2 that is in turn directly operated by crank shafts 6 and I through chains I 3. II;

is obvicus, therefore, that the shafts 6 and I and 3 valves 9 operate in timed relation.

The above described mechanism might represent any weil known internal combustion engine and the present invention aims to supply fuel to the nozzles 5. For convenience in assembly and operation the present pumping means may be mounted on top of the engine as shown in Figure 1 but 1't is to be understood that its use is not necessarily confined to this mode of assembly, it may be used remote from the engine or in other 40 locations thereon, and it may be driven from the shaft 6 in a manner to be presently described, or it may be driven from the shaft I or from an external power source if such is found desirable.

The present pump mechanism is enclosed in a. box-like casi.ng I5 that is provided with a, remova.ble cover plate I6 and flanges I'I drilled to Iacilitate its attachment on any suitable support. A pair of cam shafts I 8 and I9 are journalied in the casing I5 and are geared together at 20, one 01' the shafts being provided with a sprocket 2I that is connected by chain 22 and sprocket 23 130 cam shaft 6. Opposit e s1'de walls of the pump casing Iormed with series of ports 24 that a r'e ccnnected by lines 25 to the nozzles 5 on their respective sides of the motor.

A1; the inner end cf each outlet port 24 is formed a chamber 26 that is connected by an inlet port 21 to a fuel supply channel 28, a check valve 29 of the spring pressed ba11 type being provided to prevent flow of fuel from the chamber 26 through the port 21. A plunger 30 is mounted in the chamber 26 and is adapted, by reciprocation, to

alternatively draw fuel through port 21 and force i1: through port 24 and 1ine 25 to nozzle 5, the pressure on the fuel being sufficient to eject the fuel from the nozzle.

Each chamber 26 is providad with an enlarged bore 3I in which is received a spring 32 that engages a fiange 33 on the plunger 30 to normally retract said plunger from the chamber 26. The plungers 30 are reta.ined in chambers 26 by pierced nuts 34.

Bach plunger 30 is formed with an axia}. bore 35 in which is mounted a tappet comprising a roller 36 carried by a fork 31 having a stem 38 received in the bore 35 and normally urged. Outwardly by a compressed coiled spring 39, the spring 39 being considerably lighter than .the spring 32. A plurality of cams 40 are formed. on shafts I8 and I9, there being a cam provided in direct alignment with each plunger 30 and roller 36 carried thereby.

A plurality of inwardly projecting brackets 4I are formedon the casing I5, there being a brackiat located directly above each ro1ler 35. A iever 42 is pivotally mounted at 43 on each bracket 4 I the opposite end of the 1ever resting an cam 44 011 shaft 45. A wedge shaped finger 46 is pivotally suspended from each lever 42 by a pivot pin 41 which is so located that the wedge shaped finger is suspended netween a roller 35 and its adjacent cam 40. A saries of resilient members 48 are provided to maintain the levers 42 in comtact with their cams 44 and the shaft 45 is provided with manual means Ior rotating the same, such as the wheel 49 indicated in broken lines in Figure 3 and in Figure 5.

In operating the present pumping mechanism the cam shafts I8 and I9 are gaused to rotate. Rotation of shafts I8 and I9 causes cams 40 thereon to engage their cotresponding wedge shaped. fingers 46 and force the same to move pivotally and through contact with rollers 36 compress springs 39 and 32 and thus reciprocate the plunger 30 force fuel from the chamber 26, through port 24 and line 25 to the respective nozzle on the end thereof. II: will be noted that the spring 39 forces the tappet towards the wedge shaped. finger 46 so that the action of the cam 40 and wedgefinger 48 must comp1ess the spring 39 until the fork 31 comes into positive contact with the plunger before any movement can be realized by plunger 30. II: is obvious, therefore, that the roller 35 is constantly and resiliently maintained in contactwith its adjacent wedge fingerv and the latter is resiliently maintained in constant contact with its adjacent cam and that an idle motion exists in the operation of the device due to the fast that the roll er must be moved a certain distance before the fork 31 supporting the same engages the adjacent plunger 30. T0 adjust the pumping rate of the preser'rt device it; is necessary 1:0 increase oi decrease the amount of idle motion.

T0 increase or decrease the amou nt cf idle motion between the plunger and. its tappet the cam lowered the wedge fingers 46 are cortesrondingbr lowered and they therefore compress the spring 39 and move the fork 31 nearer 110 the plunger 30.

Accordingly a given amount o1: the movement of the wedge member 46 causes an incr'eased amount 5 of movement of the plunger 30 due to the fach that the amount of idle motion of the tappet is reduced. If the levers 42 are raised the wedge members 46 am partially retracted and accordingly permit the spring 39 to move the fork 31 so that it projects outwardly a greater distance from the plunger 30 and thereby causes an ihcrease in the amount of idle motion with a 001- responding decrease in the stroke cf the plunger 30 for a given amount of movement of finger 46. 15

Although a specific embodiment .of the present invention has been illustrated and described it is to be understood that various changes may be made in the details of construction without departing from the spirit of the inventiom as set 20 forth in the appended claims, and such changes are contemplated.

What I Claim is: 1. A fue1 injector comprising a body formed wioh a pump chamber having a. co-axial enlarge- 25 ment at one end thereof, a retainer member detachably secured in said enlargement, a plunger reciprocallyreceived in said chamber and having an enlarged portion slidably received in said retainer member, resilient means for normally urg- 30 ing retractive movement of said plunger, said retainer member functioning definitely limit the retractive mo\rement of said plunger, a tappet mounted on said plunger and extending through an aperture in said retainer member, an actuator, 35 and a stroke adjuster between said actuator and tappet.

2. A fuel injec tor comprising a body formed with a pump chamber having a co-axial v'anlargement at one end thereof providing a shoulder 40 therein, a retainer member detachably mounted in said enlarement, said retainer member having a liner portion and an end wall, a plunger having a portion slidably received in said chamher and an enlarged portion received in the liner 45 portion of said retainer member and providing a shoulgier, a spring between said shoulders and normally urging said plunger into engagement with the end wall of said retainer, a tappet; mounted on said plunger and extending through 50 an aperture in the end wall of said retainer, an actuator. and a stroke adjuster between said actuator and said tappet.

3. A fuel injector comprising a body formed with a pump chamber having a co-axial enlarge- 55 ment at one end thereof, a retainer member detachably secured in said enlargment a plunger reciprocably received in said chamber and having an enla.rged portion slidably received in said retainer member, resilient means for normally 0 urging retractive movement of said plunger, said retainer member functioning 1:0 definitely limit the retractive movement of said plunger, a tappet resiliently monted in said plunger and adapted to engage said plunger positively, said 65 retainer having an aperture through which said tappet extends, an actuator, and. a stroke ad.- juster between said actuator and said tappet.

4. A fue1 injector comprising a body formed with a pump chamber having a co-axial enlarge- 7 '-ment at one end thereof, a, retainer member detachably secured in said enlargement, a plunger reciprocably received in said chamber and having an enlarged '1aortion slidably received in said retainer member, resilient means for normally urg- 7 ing retractive movement 01 said plunger, said re tain'er member functioning to definltely llmlt the retractive movement of said plunger, said plunger having an axial bore thereln, a stem slidably received in said bore and adapted to positively engage said plunger, resilient means normally holding said stem out of engagement with said plunger, said retainer having an aperture through which said stem extends, an actuator, and a stroke adjuster between said actuator and said stem.

5. A fuel injector comprising a body formed with a pump chamber having a co-axial enlargement at one end thereof providing a shoulder therein, a retainer member detachably mounted in said enlargement, said retainer member having a liner portion and an end wall, a. plunger having a portion slidably received in said chamber and an enlarged portion received in the liner portion of said retainer member and providing a shoulder, a. spring between said shoulders and norma.lly urging said plunger into engagement with the end wall of said retainer, a tappet resiliently mounted in said plunger and adapted to engage said plunger positively, said retainer having an aperture thr0ugh which said tapp 'at extends, an actuator anti a, stroke adjuster between said actuator and said tappet.

6. A fuel lnjectbr comprising a body formed with a. pump chamber having a co-axial enlargement at; one end thereof provriding a shoulder therein, a retainer member detachably mounted in said enlargement, said retainer member having a liner portlon and an end wall, a plunger having a portion slldably received in said chamber m and an enlarged portion received in the liner portion of said retainer member and providing a shoulder, a spring between said shoulders and normally urging said plunger into engagement with the end wal1 cf said retainer, said plunger 15 having an axial bore thereln, a stem slidably receivecl in said bore and adapted to positively engage said plunger, resillent means normally holding said stem out of engagement wlth said planser, said retainer having an aperture through 20 which said stem extends, an actuator, and a stroke adjuster between said actuator and said stem.

EWALD SCHUTZNIEDRIG.

Images