US2091037A - Diesel engine - Google Patents

Description

Aug. 24, 193 7.

. ,5 WK 1 y l- J 5 1 1 Q 0 D R I\ INVENTOR.

\ .5 GILBERT c. GOODS CLARENCE w. MILLER Q g waEoReE RI-IARRINGTOM D ATToRNEx Aug. 24, 1937. e. c. GOODE ET AL DIESEL ENGINE 4 Sheets-Sheet 2 Filed Oct. 28, 19.35

A 3 o E 9 9 9 q JNVENTOR. cuss/era @0005 #gARENOE w MILLER 78B R. IMRRINGTGM ATTORNEY;

Aug. 24, 1937. G. c. GOODE ET AL DIESEL ENGINE 4 Sheets-Sheet 5 Filed Oct. 28, 1933 INVEN TOR. GILBERT 01 GUODE CLARENCE W MILLER BY MGORGE R. HARRINGTOM 6 7 ATTORNEY 4, 1937. G. c. GOODE ET AL 2,091,037

DIESEL ENGINE Filed Oct. 28, 1933 4 Sheets-Sheet 4 IN V EN TOR. GILBERT a. @0005 cz/mavas w MILLER 9 GEORGiE RJMRRINGTOM M I A T TORNE Y6.

Patented Aug. 24, 1937 DIESEL ENGINE Gilbert 0. Geode, Birmingham, Clarence w. Miller and George R. Harrington, Detroit, Mich, assignors to Chrysler Corporation, Detroit,

Mich, a corporation of Delaware Application October 28, 1933, Serial No. 695,556

Claims.

This invention relates to internal combustion engines of the fuel injection type and more especially to the mechanism for injecting fuel into the cylinders of such engines.

5 The main object of the invention is to improve the operation of an internal combustion engine of the force fuel injection type.

Another object is to improve the control of the timing of the injection of fuel in an engine of the above type.

Another object is to improve the control of the measuring of the quantity of fuel injected into the several cylinders of an internal combustion engine.

10 Another object is to provide improved means for adjusting fuel injection pumps initially to deliver accurately measured quantities of fuel.

Another object is to provide improved means in conjunction with the means measuring the Q0 quantities of fuel delivered by each of a group of fuel pumps during operationof the engine for uniformally varying the quantities of fuel delivered by the pumps so,that identical quantities of fuel are delivered to all the cylinders of the engine at any given time and the quantities delivered to each cylinder uniformally variable for variable speed operation of the engine.

Another'object is to provide improved means for preventing dribbling of fuel at the tip of the g fuel injection nozzle. Another object is to provide improved means for preventing carbonization of the tip of the I which may be lockedin non-operating position to cut a cylinder out of service.

Another object is to provide an improved type of pump plunger which is easily constructed and not subject to deflection due to high pressures encountered in fuel pumps.

Another object is to provide a timing controlled mechanism which prevents fluttering of the cam shaft and which is stable and self-locking in adjusted position.

Other objects and advantages will become apparent from the following description and appended claims.

For the purpose of illustrating the genus of the invention, a typical concrete embodiment of a fuel injection system for an internal combustion engine is shown in the accompanying drawings, in which:

Figure 1 is a side elevation, with parts broken away and in section of an internal combustion engine with a fuel injection system and control arrangement therefor constructed in accordance with the principles of this invention;

Fig. 2 is a fragmentary enlarged section taken on the line 2-2 of Fig. 1;

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

Fig. 4 is a detail view of pump elements shown in Fig. 2;

Figs. 5, 6 and '7 are sections on the lines 55, 6-5 and 'l-'l of Fig. 2;

Fig. 8 is an enlarged section on the line 8-8 of Fig. 1; 4

Fig. 9 is a perspective, partially in section, of pump elements shown in Fig. 1.

Referring to the drawings and more particularly to Figs. 1 and 3, the numeral l0 designates the block of an internal combustion engine pro vided with a plurality of cylinders H, in which are reciprocably mounted pistons l2 connected by a connecting rod 113 to a crank shaft l t. The cylinder block it is closed by means of a cylinder head l5, provided with passages it for a cooling fluid and further provided with compression chambers 20 for each of the cylinders. Cylinder head H5 is also provided with air intake passages 2i, closed by intake valves 22 the air intake passages opening downwardly into the top of the cylinders l l. The cylinder block is provided with an exhaust passage for each cylinder, designated 23, disposed laterally of the cylinders and opening upwardly into the compres sion chambers 20. The exhaust passages 23 are closed by exhaust valves 25 and the intake and exhaust valves 22 and 20 are operable by means of a cam shaft 25 driven by a gear 20 which is in turn driven by a gear 21 fixed to the crank. shaft M. Each exhaust valve 20 is operated directly by a tappet and' cam follower mechanism 30, while the air intake valves 22 are operated by a similar tappet and cam follower mechanism, push rods 3 l and overhead rocker arms 32. Valve springs 33 are provided for closing the valves 22 and 20 except as these valves are opened by the cams 3d of the cam shaft 25.

A plurality of fuel pumps 35 are provided, each individual to one of the cylinders ll, the pumps being operable by cams 36 fixed to a cam shaft 31 journaled in the cylinder block it. Fuel supply conduits 00 convey fuel to the pumps 35 either by gravity or under pressure from any suitable source. Referring also to Fig. 2 of the drawings, the pumps 35 are each provided with a discharge fuel line M extending to a fuel injection nozzle t2 mounted. in the cylinder head 55 fixed to the cam shaft 25.

gear 43, meshes with and is of the same diameter and has the same number of teeth as a gear 26 The gear 43 is not fixed to'the cam shaft 31 but is operated through a timing adjustment mechanism illustrated in Figs.

1 and 8. The timing adjustment mechanism for the cam shaft 31 varies the rotational angular relationship of this cam shaft relative to the cam shaft and includes a sleeve 44 journaled in a bearing in the cylinder block In. A retaining ring 46 and bearing 45 maintain the sleeve 44 against'axial displacement. The cam shaft 31 is hollow throughout its length and is provided with an enlarged end 41 journaled for rotation within a portion of the sleeve 44. The sleeve 44 is fixed against relative rotation with respect to the gear 43 by any suitable means such as bolts 50. Within the hollow enlarged end 41' of the cam shaft 31 and within the bore of the sleeve 44 a spline sleeve 5| is disposed. A snap ring 52 received within a suitable groove provided in the bore of the sleeve 44 retains the enlarged end 41 ,of the cam shaft 31 against relative axial displacement with respect to the sleeve 44. The spline sleeve 5| is provided with oppositely pitched teeth 53 and 54 upon the periphery of its opposite end halves. As viewed. from the right hand end of the sleeve 5| in Fig. 1, the teeth 53 are of left hand pitch while the: teeth 54 are of right hand pitch.

The pitch of the spline teeth 53 and 54 is of the same angle with respect to the axis of the 54 of the sleeve 5| and the sleeve 44 is provided with internally directed teeth 56 cooperating with the teeth 53 of the spline sleeve 5|. The pitch of the spline teeth 53 and 54 is made very slight,

an angle of 4 to -6 degrees, and of opposite pitch so that variation in speed or load upon either the gear 43 or cam shaft 31 will not cause axial displacement of the spline sleeve 5|. ,The spline .sleeve 5|, however, may be moved axially by means of a-manually controlled rod 51 extending through the hollow cam shaft 31. A manually controlled lever 60 is pivoted at an intermediate point 6| to the cylinder block l0 and pivotally connected at one end to the control rod 51 and maybe employed to axially move the splined sleeve 5|. The control rod 51 is connected to the spline sleeve 5| through a bearing 62 disposed in a recess 63 adjacent one end'of the spline sleeve and locked in position by means of a threaded ring 63- which in turn is locked to the spline sleeve by means of a snap ring 64.'

As viewed in Figs. 1 and 8, clockwise rotation of the manual controlled lever 60 will cause a .movementof the spline sleeve 5| axially to the 'left and will cause a counter-clockwise rotation of the sleeve 5| relative to the gear 43, as viewed Counter-clockwise rotation of the manual confrom the right hand end of thesefigures, and will also cause a counter-clockwise rotation of the cam shaft 31 relative to the splined sleeve 5|.

sleeve 5| by means of the manual control lever 68, the angular relation between the cam shaft 31 and the cam shaft 25 for the valves of the engine may be adjusted as desired to vary the timing of the fuel pumps relative to the intake and exhaust valves. By making the pitch of the teeth 53 and 54 of equal angles relative to the axis of the splined teeth 50, variations in load upon either the gear 43 or the cam shaft 31 for variations in speed of either of these elements, will cause the teeth 55 and 56 to exert equal and opposite forces tending to axially move the splined sleeve 5| so that no movement of the splined sleeve will result. By making the pitch of the teeth 53 and 54 less than the frictional angle of repose between these teeth and the teeth 55 and 56, accidental axial displacement of the splined sleeve 5| is largely prevented. As a i further precaution against accidental axial displacement cf the splined sleeve 5|, a brake shoe 65 may be providedcooperating with the pivot pin 6| of the manual controlled lever 60 and pressed into engagement with the pivot pin by means of a spring 66. An adjusting screw 61 may beprovided for varying the tension on the spring 66.

Referring more particularly to Figs. 2, 5, 6, '7, 9 and 4, the construction of one of -the fuel pumps .will be described. An individual fuel pump is provided for each cylinder and comprises a housing 10 within which is rotatably mounted a plunger barrel 1| and a plunger 12 is rotatably mounted within the plunger barrel. The plunger barrel 1| is normally maintained against rotation relative to the housing by means of an eccentric locking-pin 13, fixed to an adjusting nut 14 and cooperating with a slot 15 is the plunger barrel to adjust the rotative position of the plunger barrel relative to the housing 10. The fuel injection pump is of the constant stroke type and the plunger 12 is operated by means of a cam 38 fixed to the cam shaft 31. The lower end of the pump plunger 12 is provided with .a head 16 which is rotatably secured between the bottom closed end of a plunger guide 11. and a spring plate secured to the plunger guide. A plunger return spring 18 is arranged in compressed relation between the lower spring plate 88 and an upper spring plate 8| for the purpose of maintaining the plunger guide in contact with the cam 36. The upper spring plate 8| also serves to maintain a control sleeve 82 in position within the pump housing and in surrounding relation with respect to the plunger barrel 1|. The upper end of the control sleeve 82 is in the form of a gear 83 interposed between the upper spring plate 8| anda shoulder 84 provided in the housing 10, the gear cooperating with a tooth control rod 85 common to all of the fuel injection pumps of the engine. Adjacent its upper end, the plunger guide 11 is provided with a groove 86 with which a locking pin 81- is adapted to cooperate to lock the plunger and guide in an elevated position so that the pump may be assembled or disassembled with respect to the engine as a complete unit or by which any of the cylinders of the engine may be thrown out of service as desired.

To adjust the quantity of fuel delivered by the pump at each stroke of the plunger 12 an axially arranged slot 80 is cut in the periphery of the plunger and extends into the upper end surface of the plunger. The plunger 12 is also provided with a gear 9| adjacent the lower end portion thereof on which are formed spirally arranged teeth, adapted to cooperate with correspondingly formed spline teeth 92 provided on the interior surface of the lower end of the control sleeve 82. With the control sleeve 82 fixed in position, upward movement of the plunger 12 also causes rotation of the plunger to bring the slot 90 into registration with an intake port 93 provided in the plunger barrel H. The control sleeve 82 may be fixed in position, as for example by the control rod 85, and with the control rod in retracted position the time at which the slots 99 would register with the ports 93 may be adjusted by means of the eccentric lock pin 13 so that a proper amount of oil may be delivered by the fuel pump for oper ating the engine at idling speed. The rotative position of the pump barrel ll of each of the pumps may be adjusted in this manner so that each pump will deliver an accurately measured and uniform quantity of fuel. The eccentric lock pin 13 functions both to hold the plunger barrel in adjusted position and to varythe adjustment of the rotative position of the plunger barrel to vary the initial quantity of fuel delivered by each pump so that uniform delivery of all pumps may be obtained. The pump plunger has a continuous periphery, except for the slot 99 cut in the end of the same. The pump plunger has little tendency to bend even when operated under extremely high pressures to which the pumps are subjected.

There will be no wear of the pump plunger or plunger barrel due to misalignment of the end portion of theplunger opposite the slotted portion due to high pressures encountered within the fuel injection pump.

Ar intake passage 9d is provided in the pump housing 76 and extends between the port 93 in the sleeve of the plunger valve H and the conduit 40 adapted to supply fuel. by gravity or from a sourc of fuel under pressure.

In the operation of the pump, elevation of the pump plunger 12 will cut off communication be tween the compression chamber 95 above the plunger and the intake passage 94 as soon as the plunger has moved above the intake port 93.

- The plunger 72 will force the fuel from the compression chamber and by the delivery valve 95 until such time as the slot 99 has been brought into registry with the intake port 93. When the slot 90 is brought into registry with the intake port 93 the pressure is relieved within the com-.

pression chamber and excess fluid-is forced back "through the slot 90 and port 93 into the intake passage 99. As the pressure is released inthe compression chamber 95 through the slot 99, the valve 96 will again seat against the shoulder 97 provided in delivery valve sleeve 99.

As will be noted from Figs; 2 and 4, upward movement of the pump plunger 12 will cause clockwise rotation of the plunger relative to the, pump housing as viewed from the bottom of the pump. Thus if the plunger valve 7! is rotated from the bottom of the pump will decrease the 1 interval between the closing of the intake port 93 and the point at which the pressure within the compression chamber '95 is relieved through the slot 90 so that a smaller quantity of fuel will be delivered at a single stroke of the plunger. It

will also be noted that the interval may be lengthened or decreased by rotating the control sleeve 82 in a counter-clockwise or clockwise direction, respectively. The throttling control of the engine may be exercised in the latter manner. The throttle control of the engine is connected to the control rod in order to rotate the control sleeve 82 in a counter-clockwise direction and increase the interval between the closing of the port 93 and release through the slot and port 93 to increase the quantity of fuel delivered to the cylinders of the engine. Opposite movement of the control rod causes clockwise rotation of the control sleeve 82, decreases the interval between the closing of the port 93 and release through the slot 99 and intake port 93 and decreases the quantity of fuel delivered to the cylinders of the engine.

The discharge valve 96 is preferably in the form" when the valve is in closed position. Thus there will be a high unit pressure tending to maintain the valve 96 in closed position. During the up-' stroke of the plunger 72, pressure within the compression chamber is instantly reduced as soon as the slot 90 comes into registry with the intake port 93. There will then exist a greater pressure in the delivery piping 98 than in the compression chamber. This difference in pressure will move the delivery valve 96 downwardly against its seat,

this movement being aided by the delivery valve spring 899. During the movement of the valve 96 downwardly within the bore 99, the cylindrical valve will act as a piston within this bore and relieve the pressure within'a delivery piping to prevent dripping of fuel from the tip of the deliv-' ery nozzle 92 into the combustion chamber of the engine.

Downward movement of the valve 96 within the bore 99 withdraws a small amount of fuel back through the delivery piping relieving the pressure within this piping and causes instantaneous closing of the nozzle valve or needle H02 within the delivery nozzle Hill to prevent dribbling of fuel into the combustion chamber of the engine. It will be noted that the throttle control rod 85 may be controlled by a manual means or by means of agovernor on both for either of manual, automatic or combined manual-automatic control of the engine. I

Referring to Figs. 1 and 2, cooling fluid piping E95 leads from a cold point of the cooling system (not shown) for the engine and conduits M6 individual to each delivery nozzle Mil convey cool fluid to the tip ofeach delivery nozzle. This cools the tip of the nozzles and prevents carbonization of the fuel at the nozzle tips.- The conduits )6 lead into the cooling fluid passages i6 and return the cooling liquid employed to the cooling system at these points.

As many changes could be made in the above described constructions and many ,apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter pertaining to the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. What is claimed is:

1. A fuel pump comprising a housing provided with a cylinder, a pump plunger reciprocable in said cylinder, means for reciprocating said plunger with a constant stroke in said cylinder, means for oscillating said piston substantially continuously during its entire reciprocation, said plunger having a slot provided in the periphery thereof and extending into the working face of the plunger for relieving the pressure in said cylinder and interrupting the discharge therefrom, and a relief port in the wall of said cylinder registerable with said slot upon oscillation of said plunger throughout a predetermined range of its oscillative movement.

2. A fuel pump comprising a casing provided with a cylindrical sleeve, a plunger reciprocable in said sleeve, means for reciprocating said plunger with a constant stroke, said means including positive acting apparatus for urging said plunger through the fluid displacing portion of itsreciprocating movement in said sleeve, means for oscillating said plunger during its reciprocation, including a rotatable member and contacting elements on the latter and said plunger for oscillating said plunger during axial movement thereof relative to the cylinder and member, said plunger having an axially disposed slot provided in the periphery thereof and extending into the working face of the plunger, a port in the wall of said sleeve, registerable with said slot, upon oscillation of said plunger, and means for rotating said.

plunger independently of its axial movement and through the medium of said co-acting elements including variable control apparatus so constructed and arranged as to rotate said member.

3. A fuel pump comprising a casing provided 40 with a cylindrical sleeve, a plunger reciprocable terable with said slot upon rotation of said plunger, means for rotatably adjusting said cyl- 50 inder relative to said housing, and control apparatus operatively connected with said means for oscillating the piston during its reciprocation for adjusting the rotative position of said plunger relative to said cylindrical sleeve through the action of said piston oscillating means.

4. A fuel pump comprising a casing, a sleeve rotatably mounted in said casing and provided with a cylinder, a piston reciprocable in said cyl-, inder, means for reciprocating said piston with a constant stroke in said cylinder, means for oscillating said piston during its reciprocation in-v cluding an internally helically splined tube surrounding said piston and rotatable relative to said casing, said piston having elements thereon cacting with the splines of said tube and having an axially disposed slot provided in the periphery thereof and extending into the Working face of the piston, said sleeve being provided with a port opening into a wall of said cylinder and registerable with said slot in said piston upon rotation of the latter, means for locking said sleeve in rotatably adjusted position with respect to said casing to vary the amount of oscillation of said piston that thepiston must make before bringing said slot into registry with said port, and means for rotating said piston independently of its reciprocation including control apparatus adapted to rotate said tube and said piston in unison through the action of said splines and co-acting elements on said piston.

5. A fuel pump including a housing, a cylinder in said housing having inlet and outlet ports, a

reciprocable and rotatable pump plunger in said cylinder having an opening in its periphery leading to its discharge end and normally angularly disposed with respect to said inlet port and registering with a continuous Wall portion of said 'cylinder during the effective portion of the fuel displacing stroke of said plunger, said inlet port being so disposed as to be closed by said plunger at the beginning of the effective portion of the fuel displacing stroke thereof, and means for positively moving said plunger axially and simul taneously rotating the latter in a substantially predetermined timed relationship during the effective portion of its fuel displacing stroke for bringing said opening and said inlet port into communication with each other to terminate the discharge of fuel

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