US2474121A

US2474121A - Control of fuel-injection engines

Info

Publication number: US2474121A
Application number: US741807A
Authority: US
Inventors: Sanders Arthur Freeman
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-09-09
Filing date: 1947-04-16
Publication date: 1949-06-21
Anticipated expiration: 1966-06-21

Description

June 2l, 1949. A F, SANDERS CONTROL OF FUEL INJECTION ENGINES Filed April 16, 1947 FIC l FIG Z- FIG 3 JNVENToR. Jah/T3719 Patented June 2l, 1949 UNITED STATES PATENT OFFICE Application April 16, 1947, Serial No. 741,807 In Great Britain September 9, 1942 Section 1, Public Law 690, August 8, 1946 Patent expires September 9, 1962 3 Claims.

This invention relates to a fuel-injection engine such as has a device, responsive to the lubrication pressure of the engine, which is associated directly or indirectly with the main fuel control member of the fuel pumping unit so as to cut olf the fuel delivery if the lubrication pressure falls below a predetermined value.

According to the invention, the device also limits the maximum fuel delivery in running conditions. Furthermore, the device is preferably adapted also to provide an excess fuel delivery (beyond the normal maximum) at starting.

In the accompanying drawings:

Figure 1 is a sectional elevation of a device according to the invention;

Figure 2 is a plan thereof; and

Figure 3 is a fragmentary elevational view showing an alternative means of operation.

In the construction shown the device is carried by a bracket I bolted or otherwise secured against an appropriate wall of the fuel pumping unit I I, the device comprising a vertical cylinder l2 connected at its lower end to a pipe I 3 leading to the lubrication system of the engine (not shown) so as to receive the pressure thereof. In the cylinder is disposed a plunger I4 biassed downwardly by a combined torsion and tension spring I5, a stop being provided to limit the outward movement of the plunger. The latter has a cylindrical portion I6 outside the cylinder, and above that a truncated cone portion I 'I, which parts can coact, dependently upon the lubrication pressure, with a roll-er I8 carried at the end of the main fuel control member I9 of the pump unit. On one side of the truncated cone portion is milled a slot 20 of a width to receive the roller, the bottom of the slot curving out to join the cylindrical portion I6 of the plunger.

Normally the slot is away from the roller, as shown by Figure 1, and when the engine is stationary the roller engages the upper end (maximum diameter) of the truncated cone portion, the fuel delivery then being cut ofl", as shown by the full lines. To start the engine the plunger is turned through 180 to bring the slot 20 of the truncated cone portion into alignment with the roller, thus subjecting the biassing spring I to a torsional stress, and the main fuel control member I9 can then be forced by the normal governor spring into a position in which excess fuel, f

(Cl. 12B-140) 2 the roller to the left (Figure 1) and out of the slot 20. Also, the lubrication pressure building up beneath the plunger will force this outwardl;T against the tension of the biassing spring I5 until the roller is quite clear of the slot 20, and, in fact, the cylindrical portion I6 of the plunger is in line with the roller, as shown by the chain lines of Figure 1. The cylindrical portion I6 will then determine the maximum fuel delivery as long as the lubrication pressure is maintained. When the roller is quite clear of the slotl 2% the torsion of the spring I 5 will twist the plunger to move the slot out of alignment with the roller, i. e., back to the position of Figure 2.

In the event, however, of the lubrication pressure failing, the spring acting upon the plunger will return the parts to the engine-stationary position shown by the full lines of Figure 1, the inclined surface of the truncated cone portion acting on the roller to force the main fuel control member I9 to the fuel cut-off position. The roller may be supported against side thrust as necessary.

To stop the engine the plunger can be pushed down manually and held down until the engine is stopped; and, if desired, provision may be made for effecting this, or for turning the plunger to the starting position, from the dashboard or the like accessible place in the case of a motor-vehicle having an engine fitted with the device of the invention.

A remote control means is illustrated in Figure 3, in which the plunger is shown in the stop position. The end 22 of a Bowden or like control is wound round and appropriately secured to an exposed portion of the plunger. In addition, a Bowden or like control 23 is connected to a lever 24 the free end of which is adapted to coact with the head ofl the truncated cone portion Il of the plunger. The drawing shows the parts when the control 23 has been pulled to cause the lever 24 to force the plunger downwardly against the oil pressure, thereby stopping the engine. By means of the control 22 the plunger can be rotated through to bring the slot 20 into co-operation with the roller I 8, whereby to place the main fuel control member in the starting position, as above described. As the engine starts the roller I8 will tend to be withdrawn from the slot 2t and the oil pressure will tend to lift the slot 2li clear of the roller, such that the plunger can be turned by the spring l5 back to the normal running position-assuming, of course, that the control 22 has not been held in the starting position and that the lever 24 is likewise free to turn from the position shown in Figure 3.

Furthermore, by arranging the cylindrical portion I6 to be eccentric, or shaped as a cam, as indicated by the dash-dot line 16a: in Figure 2, and by providing means for manually twisting the plunger when desired, the maximum fuel delivery can be adjusted when desired.

Furthermore, electric contacts may be arranged and connected up to illuminate a pilot light in the event of the lubrication pressure failing, so as to obviate the likelihood of the driver attempting to restart the engine without investigating the trouble.

Obviously, instead of using a piston form of plunger, use may be made of a diaphragm or bellows device, or some other form of hydraulic device may be used, provision being made for its torsional control as well as for its axial movement.

What I claim as my `invention and desire to secure by Letters Patent of the United States is:

1. For a fuel-injection engine, the combination with a fuel pumping unit having a main fuel control member, of a plunger having a head coacting with said member, said head having a frusta-conical portion the smaller diameter of which is adjacent an eccentric cylindrical portion, means biassing said plunger to a position in which the larger diameter of said frustoconical portion engages said member to cut off the fuel delivery, means for applying the lubrication pressure of the engine to said plunger to force it against the biassing means so that, when the engine is running normally, said cylindrical portion engages said member to limit the maximum fuel delivery, and means for partially rotating the plunger to control the maximum fuel delivery when the engine is running normally.

2. For a fuel-injection engine, the combination with a fuel pumping unit having a main fuel control member, ofv a plunger having. a head coacting with said member, said head having a frusto-conical portion the smaller diameter of which is adjacent a cylindrical portion, means biassing said plunger to a position in which the larger diameter of said frusto-conical portion engages said member to cut off the fuel delivery, means for applying the lubrication pressure of the engine to said plunger to force it against the biassing means so that, when the engine is run- 5G ning normally, said cylindrical portion engages said member to limit the maximum fuel delivery, said plunger having a longitudinal peripheral groove through the frusto-conical portion to receive the adjacent end of said member, the bottom wall of said groove being nearer the axis of the plunger than the periphery of said cylindrical portion, and means for partially rotating the plunger to enable said member to enter said groove and to thus increase the maximum fuel delivery above normal when the engine is being started.

3. For a fuel-injection engine, the combination with a fuel pumping unit having a main fuel control member, of an angularly and axially movable plunger having a head coacting with said member, said head having a frusto-conical portion the smaller diameter of which is adjacent a cam portion, and said frusto-conical portion having a longitudinal peripheral groove in it to receive the adjacent end of said member, the bottom Wall of said groove being nearer the axis of the plunger than the periphery of said cam portion, means biassing said plunger to a position in which the larger diameter of said frustoconical portion engages said member to cut off the fuel delivery, with said groove spaced angularly from said member, means for applying the lubrication pressure of the engine to said plunger to force it axially against the biassing means so that, when the engine is running normally, said cam portion engages said member to limit the maximum fuel delivery, and means for partially rotating the plunger 'against said biassing means to control the maximum fuel delivery when the engine is running normally and to enable said member to enter saidgroove to increase the maximum fuel delivery above normal when the engine is being started.v 1

ARTHUR FREEMAN SANDERS.

REFERENCES CITED They following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,201,123 Davis May 14, 194i) FOREIGN PATENTS Number Country Date 408,760 Great Britain .Apr. 19, 1934