US1115180A - Fuel-pump. - Google Patents

Description

0. DAY & G. E. WINDELER.

FUEL PUMP.

APPLICATION FILED JULY 21, 1913.

Patented Oct. 27, 1914.

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H 6 Q d m Wk? IIE n S F z w om & to N ne e6 .m X M a e r W 0% m w W Specification.

nrrnn PAW CHARLES DAY AND GEORGE EDWARD WVINDELER, 0F STOCKZPOBT, ENGLAND, ASSIGN- OBS T0 GENERAL ELECTRIC COMPANY, A CORPORATION 0E NEW YORK.

- FUEL-PUMP.

Original application filed June 13, 1912, Serial No. 703,395. Divided and this application filed. July 21, 1913.

Specification of Letters Patent.

Patented @ct. 2?, 1914i.

Serial No. 780,106.

To all whom it may concern:

Be it known that we, CHARLES DAY and GEORGE E. VVmnnLnn, subjects of the King of Great Britain, residing at 'Stockport, county of Cheshire, England, have invented certain new and useful Improvements in Fuel-Pumps, of which the following is a The present application is a division of our pending application, Serial No. 7 03,395, filed June 13, 1912, which division is made at the requirement of the United States Patent Ollice.

'Our invention relates to pumps for supplying liquid fuel to high compression internal combustion'engines and has for its object to improve their construction and operation. Pumps of this class commonly supply fuel at a pressure greater than the compression pressure of the engine; this, for example, may require a pump to deliver fuel at a pressure of 500 to 800 lbs. per square inch or even higher. Such a pump to be satisfactory in service must be well made in every particular.

The difliculties in makinga single plunger pump, while many, are not so great as in making multiple plunger pumps. In the lat ter case great-difficulty is experienced'in bor- I ing the, cylinders and drilling the crossheads with the exact pitch distance between them and in so positioning the cylinder bores and cross-head holes when assembled that they are directly alined. In this connection it is to be borne in mind that there can be noside clearance between the plungers and cylinder Walls, the parts being fitted as snugly as possible. We solve the problem by so arranging the plungers that they are self alined or self centered with respect to the cross-head.

Other features of our invention will be referred to later.

In the accompanying drawing which illustrates one of the embodiments of our invention, Figure 1 is a vertical section of a fourcylinder fuel pump, and Fig. 2 is afront elevation thereof. Y

"6 indicates" the main body of the pump that is made ofcast metal and is secured by bolts or other means to the engine frame 7, The lower part of the casing contains a supply chamber 3 which is filled with oil from a supply pipe 9 leading to a tank. Air is admitted to the pipe and chamberby the pipe 10. The bottom of the casing is provided with a removable cover 11 having an oil trough 12 to receive all leakage. This with a separate liner 14 which can be har' dened to reduce wear and later ground externally to exact size to fit the opening in the casting. This is a very advantageous an rangement if the body casting contains small blow holes or other imperfections. Without such a device the whole casting would have to be discarded and these are expensive. Moreover it often happens that the imperfections are not in evidence until considerable work has been done on the cast.

ing. "Whichever way the cylinder is made it should be carefully reamed to exact size.

In each cylinder is a hardened and carefully ground plunger 15 that is snugly fitted in the cylinder or liner and is ro'vided with small grooves 16 t reduce eakage. The

plunger passes through a stufiing box 17 of suitable construction, which also holds the liner in place by engaging the 11 per end thereof. The upper end of each p unger is provided with a cylindrical enlargement .18 which passes through the actuating cross-- head 19. The 11 per end of the enlargemel... terminates in a liead 20 having a flat under side which engages a finished surface on the upper side of the cross-head- The lower end of the enlargement is threaded to receive the nut 21. Between the finished surfaceon the under side of the cross-head and the nut is a hardened and ground washer 22 to receive the downward thrust on the working stroke. The wa nicely ed to the cross-head so that there is no trust motion in the vertical direction. After the parts are properly fitted the nuts are held against rotation by cotter pins. It will be noted, however. that the enlargement 18 does net-"fill the hole in the cross-head, a small clearance being left all ad it.

too 381 and head 20 are closely and This is to permit of the plunger being guided by the cylinder wall instead of by the cross-head thereby compensating for faulty alinernent orinaccuracies in machine work. Another way to look at it is that the cylinder determines the position of the plunger and also guides it while the cross-head serves solely as an'actu'ator, moving the plunger into and out of the cylinder. At

, this point it is well to bear in mind that 'of the plungers are similarly constructed.

In assembling they are slipped through the holes in the cross-head from above, after .which the nuts 21 are mounted in place.

The cross-head may be of any suitable shape and size provided it is strong and can be well guided. It is provided with as many correspondingly spaced holes as there are plungers, the top and bottom surfaces 00- operating on the plunger parts being carefully finished and exactly perpendicular to the axis of said holes. The back of the cross-head is enlarged as at 23 to form a good support and said support moves yertically in guides 24. This results in ample guiding surfaces with correspondingly low pressures thereon thus reducing wear. The cross-head is also provided with two flange pieces 25 through which the removable pin 26 extends, said pin connecting the lower end of the eccentric rod 27 and the crosshead for actuating the plungers. The pin is normally held in position by a pivoted latch 28 that enters a small groove 29 therein. By removing the pin 26. swinging the eccentric rod 27 out of the way and mounting the lever 30 in place as shown by dotted lines with its pin in the place of pin 2 6 the pinup can be actuated by hand to fill the pipes leading to the fuel iniectors or pulyerizers in the engine and thus force out any air which may be contained in the system. After this the parts are replaced and the en- I gine will be ready for operation. This hand "i113: 18 only desirable or necessary afh been shut down for a perioc. of time. The cross head is driven by an eccentric 31 that is mounted. on the end of the shaft 32, driven by the main engine shaft and may be the shaft which carries thecams for actuating the engine valves. Motion from the eccentric is transmitted to the cross-head by the rod 2'i and the eccent rap 33.

....l a o is connected by a rod 42 to the lever 43 i which is yibrated'in synchronism with the crosshead, sa1d lever having a fulcrum 4A that is adiusted by the rod 45' of the governing mechanism to cause the suction valves to close earlier or later as the demand for fuel changes.

Certain of the novel and useful features illustrated and described in this application and not claimed herein form the subject matter of our aforesaid application, Serial No. 703,395, filed June 13. 1912.

In accordance with the provisions of the patent statutes. we have described the prim ciple of operation of our invention together with the apparatus which we now consider to represent the best embodiment thereof; but we desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means. 4

What we claim as new and desire to secure by Letters Patent of the United States, 1s:

1. The combination with a frame, of a body firmly secured thereto and containing a plurality of separately spaced pump cylinders,

. with their axes in the same plane and countersunk at their upper ends, a liner for each cylinder closely fitted therein, and all of said liners bein finished to exactly the same size, a stu ng box in the countersunk upper end of each cylinder holding the liner in place, a plunger fitting each liner and passingthrough the stuffing box, a cylindrical enlargement at the upper end of each plunger haying screwthreads at its lower end and terminating in a head having a flat under side, a nut engaging said screwthreads, a hardened and ground washer above said nut, a crosshead having a plurality of holes to receive said enlargements with a clearance all around them, the upper and lower surfaces of the crosshead being parallel and finished to afford a nice sliding fit for the terminal head and the Washer respectively, guides on the frame for said crosshead, and means for reciprocating said crosshead.

2. The combination with a plurality of pump cylinders, of plungers therein, a crosshead engaging said plungers, two flange pieces on the crosshead, a removable pin passing through said flange pieces, a latch for holding said pin in place, a driving shaft operatively connected to said pin, and

a stationary fulcrum for a lever adjacent to said pin.

3. The combination with a plurality of pump cylinders, of a plunger for each cylto enter their cylinders, and the enlargements thereon will be received in said holes, and means for preventing axial play of said enlargements in said holes without prevent- 5 inder having a cylindrical enlargement of ing lateral play therein.

greater diameter than the plunger or its shank, and a reciprocating crosshead having a plurality of cylindrical holes in line with said cylinders and enough larger than said 2 enlargements to afford a good clearance all around them, whereby the plungers can be passed through the holes in the crosshead Gopt'os or this patent may be obtained for In witness whereof, we have hereunto set our hands this first day of July, 1913.

CHARLES DAY. GEORGE EDWARD WINDELER. Witnesses:

. ERNALD SIMPSON MosELEY,

ALEX. F. MACDONALD.

five cents each, by addressing the Commissioner of Patents, Washington, D. G. 1

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