US761768A - Mixing-box for gas-engines. - Google Patents

Description

v ernor it automatically determines at anyin- UNITED STATES- Patented June 7, 1904.

PATENT OFFICE.

LAVVRENOE M. JOHNSTON, OF DAYTON, OHIO, ASSIG-NOR TO THE NEIV ERA GAS ENGINE COMPANY, OF DAYTON, OHIO.

MIXING-BOXIFOR GAS-ENGINES.

SPECIFICATION forming part of Letters Patent No. 761,768, dated June '7, 1904.

Application filed June 9, 1902.

specification.

My invention relates to improvements in the mixing-boxes of gas-engines, wherein the air is mixed with the gas to form the explosive mixture and by which the mixture is sup-.

plied to the cylinders of the engine.

The primary object of my improved mixing-box is to automatically control the supply of gas to the mixing-chamber and to automatically control the supply of the explosive mixture from the mixing-chamber to the engine-cylinders, so that the supplyof gas to the mixture and the supply of the mixture to the engine-cylinders shall be always proportional to the work to be done' by the engine. In other words, the operation of my mixing-box is such that in connection with a suitable govstant the amount of gas admitted to the mixing-chamber andthe amount of the explosive mixture admitted to the cylinders for each explosion, so that when the .load is light a small proportion of gas is used in the mixture and a small amountof the mixture is admitted to the cylinders and, on the other hand, when the load is heavya proportionately larger amount of gas and of the mixture is used, so that at any instant just the right proportion of gas and just the right quantity of the mixture are admitted to the cylinders to produce an explosion of suflicient'force to operate the engine under its load at that instant. With the use of my improved mixing-box I am thus enabled to havethe explosions occur at regularintervals and not at varying intervals, as is now the general practice, and I find that its use cond uces to a high efficiency of the engine with an economical expenditure of gas.

A secondary object of my improved mixas No. 110,789. (No model.)

ing-box isthe control by the operator of the I supply of air to the mixing-chamber and also the primary control by the operator of the ever. as I have before stated, is automatically determined.

The various advantages of my mixing-box will appear more fully as I proceed with my specification.

In the drawings, Figure l is a front elevationof my improved mixing-box. Fig. 2 is a top plan view of Fig. 1 with the short pipe at the top removed and with a portion of the outer cap ofthe mixing-box removed. Fig. 3 is a vertical section on the line 3 3 of Fig. 1. Fig. 4 is a cross-section on the line 4 A of Fig. 1. Fig. 5 is a rear elevation of the mixing chamber, showing the ports partially closed. Fig. 6 is an elevation of the inner cylinder of the mixing-chamber.

My improved mixing-box, as shown, consists of a mixing-chamber surrounded at its upper end by a gas-chamber and at its lower end by a mixture-chamber, the. first communicating with a source of gas-supply and the latter communicating with the cylinder-heads of the engine. The air is admitted directly into the mixing-chamber, and its supplyis under the control of the operator. I also prefer to use a suitable mechanism for controlling the supply of gasto the gas-chamber,

this being one of the secondary elements of my invention.

Referring now to the drawings, A Is the outer casing, preferably of cylindrical form, which of the gas-pipe that is to convey the gas-supply. A short cylinder E fits snugly within the upper end of the casing A, so as to be capable of rotation, and rests upon an annular offset E on the inner face of said casing. This offset divides the casing and serves,'in connection with the mixing-chamber, as will appear presently, to form an upper gas-chamber X and a lower mixture-chamber Y, surrounding said mixing-chamber. The cylinder E is provided with aslot E, which registers vertically with a slot F in the outer casing A in the line of the gas-supply, as best seen in Fig. 4. It has a handle 6, which projects through a slot (2' in the outer casing A and serves to move the cylinder E so as to make the slot E register in its horizontal movement either entirely, partially, or not at all with the slot F, in which latter position, of course, no gas would enter the gas-chamber. Thus by moving the cylinder E the flow of gas into the gas-chamber may be regulated and varied by the operator from nothing to a maximum. The handle 6 is provided with a needle 0, which travels over a gage on the face of the outer casing and indicates the effective size of the opening through the slots E F, so that the operator is enabled to gage the size of the opening and through it the supply of gas to the gas-chamber.

Fitting within the upper end of the casing A is an inner cap G, provided on its upper side with an annular socketin which fits a rotatable disk G. The bottom of this inner cap and the disk G are respectively provided with ports g and g, which by the rotation of the disk G may be caused to register either entirely or only partially with each other. The disk G has a handle 9, extending through a slot g in the cap G, which serves to rotate the disk and in connection with a needle 7t and a scale over which it travels to regulate and indicate the proportionate size of the efiective openings through the ports 9 g. An outer cap H fits aboi e the inner cap G and the disk Gr and serves to hold the latter in place, the two caps being secured to the casing A in any convenient manner. The capH has an opening H, usually surmounted by a suitable pipe I for admitting air to the ports 1 g. The pipe I, or when it is not used the opening H, is open to the air. The ports 9 are preferably made larger than the ports 9, so that the admission of air can never be entirely cut off. As will presently appear, these ports are directly above the mixing-chamber and open directly into it.

I have thus far described the arrangement by which the gas and air are respectively admitted into the mixing-box and how the quantity of each may be respectively varied by the operator, so as to approximately deter mine in the first instance the proportions of the two in the mixture.

1 have now to describe how the gas is admitted to the actual mixing-chamber and how the mixture of gas and air is admitted to the cylinders and the means whereby in each case the quantities are automatically controlled and determined by the engine.

The mixing-chamber Z consists of an inner and outer cylinder, the one movable upon the other, and, as will be shown, the movement of the slidable cylinder is the means through which the effective size of the ports of the mixing-chamber is determined.

J is the outer cylinder and is secured within the casing A, with its upper end bearing against the lower side of the inner cap (1 and its sides bearing against the annular ofl'set E on the inner side of the casing A. The parts are so ground at these points as to lit together gas-tight, thus forming the upper and lower chambers X and Y, surrounding the mixingchamber Z, as above stated. The cylinder J is prolonged below its attachment to the easing A and is screw-threaded on its inner side at the bottom to receive a seat J", provided with a suitable stuffing-box J. through which passes a rod K. This rod K is secured at its upper end to the bottom K of the inner cylinder K. The mixing of the gas and air takes place within this inner cylinder K. \Vhen in its highest or normal position, the cylinder K bears against the bottom of the inner cap G, and it is prevented from horizontal rotation by means of a pin 1 and slot 2, the former on the outer cylinder J and the latter on the inner cylinder K. the slot being open at the top, so as to permit the inner cylinder to be removed.

The inner and outer cylinders are provided with two sets of ports or holes which normally register with each other, of which one set is located opposite the port D in the casing A and the other is opposite the slot F, through which the gas-supply is admitted to the easing A, these ports being marked in the drawings respectively 117' and Z1 j. A coil-spring Z on the rod K bears between the bottom of the cylinder K and the top of the seat J, and tends to hold the cylinder K in its highest or normal position, with the ports in the two cylinders exactly registering with each other.

The rod K is provided at its lower end with a milled nut M, which is capable of up-anddown adjustment and which is provided with an annular groove in which is pivoted, by means of suitable trunnions, the end of a swinging arm M. This arm M is pivoted intel-mediate its ends to the engine-cylimler and has its other end suitably connected to a slide which is operated up and down by the governor-balls, the arrangement being such that when the balls fiy apart on accounto'l the in creased rapidity of movement of the engine the arm M is depressed at its connection with the nut M and is raised when the halls approach each other as the engine slows down. This connection of the arm M to the slide and IlO lstood that the rate of flow of gas from the gasthe smaller load the proportion of gas in the operating governor-balls is not shown in the drawings, as it 1s the usual. construction and is readily understood without illustration.

It is apparent that as the arm M is depressed by reason of the increased speedof the engine (by this is meant a speed above that at which the engine is designed to run under all loads) the rod K, and with it the cylinder K, is pulled mixing-chamber. If the cylinder be depressed.

far enough, as when the' engine runs away, the ports of the mixing-chamber are entirely closed, thereby cutting off the gas-supply from the mixing-chamber and the supply of tlhe explosive mixture from the engine-cyliners.

From the above it will be readily underchamber X to the mixing-chamber Z and of the explosive mixture from the mixing chamber to the mixture-chamber Y and thence through the ports D D to the engine-cylinders is under the direct control of the governorballs. Thus when the load is decreased and the engine begins to speed up on account of mixture is decreased, and the amount of the mixture supplied to the cylinders is also decreased, and vice versa. In other words, the amount of explosive mixture supplied to the engine-cylinders and the proportion of gas in the mixture at any instant is automatically determined by the engine itself.

To prevent an air cushion from being formed between the seat J "and the bottom of the cylinder K, which would interfere with the easy operation of the movable cylinder, the bottom K of said cylinder is provided with openings 3.

The amount of air which enters the cylinder K is of course, as I have shown, at all times regulated by the operator. The operator also determines the flow of gas into the gas-chamber X, and thus in the first instance approximately determines the relative proportions of the gas and air in the mixture; but the engine itself automatically determines the exact proportions in the mixture and the rate of supply to the engine-cylinders at any instant.

By making the nut M adjustable the proper position of the-end of the arm M may be exactly determined, so as to have the ports of the mixing-chamber fully open when-the engine is running at the designed speed under its maximum load. In order to observe the operation of the movable cylinder K and see the size of the effective openings of the ports in the mixing-chain ber, I prefer toprovide the outer casing with a sight or peep hole P, covered by a glass P. Opposite this I place ports 3', respectively, in the cylinder K and the cylinder J, having the same relative arrangementand the same size as the other ports in these cylinders. It is thus apparent that the ports will vary just as the others do, so that it is possible to see the effective size of the ports at any instant. The peep-hole P is thus of value iii-adjusting the parts.

I have thus described the preferred arrangement of my improved mixing-box; but I do not wish to limit myself to the exact construction andarrangement described. It is apparent that the construction may be widel y varied Without departing from the spirit of my invention. As a single instance of the possible mechanical variations the movable cylinder of the mixing-chamber might be the outer cylinder instead of the inner cylinder, as I have described it, with such mechanical changes as are necessary to bring about its operation in this manner. Other changes of form and arrangement are possible, and I shall not attempt to point them outf Again, it is possible to make use of only portions of my improved mixing-box without add-ing to' it'all the details which I have described. These matters will be apparent to a mechanic skilled in the art, and I shall not attempt to discuss them, but shall now point out in the claims what I consider as new in my invention and what I desire to cover by Letters Patent.

tomatically determined by the engine, substantially as and for the purpose described.

2. In a mixing-box for gas-engines, a mixing-chamber, an air-chamber located. above said mixing-chamber, a partition between said air and mixing chamber provided with ports, a rotatable disk provided with corresponding ports located above said partition and provided with means for rotating it, a gas-chamber connected to a source of gas-supply, and a hand-valve controlling said supply, ports connecting said gas and mixing chamber, ports connecting said mixing-chamber with a passage leading to the engine-cylind ers, and mechanism whereby the effective size of said ports at any instant is automatically determined by the engine, substantially as and for the purpose described.

8. A mixing-box for gas-engines comprising an outer casing opening into the cylinderheads at its lower end, and having lugs for securing it to said cylinder-heads, fixed and longitudinally movable cylinders disposed therein, both suitably capped at the bottom and being supported against internally-disposed offsets on the outer casing, one at the middle and one at the bottom, ports in said cylinders connecting the annular chambers thus formed about them with their interior, a rotatable cylinder fitting the internal bore of said outer casing and resting on said middle oflset, registerable slots in said rotatable cylinder and said outer casing adjacent a source of gas-supply, a cap resting on the tops of said outer casing and said cylinders, a disk disposed above said cap, said disk and said cap being provided with registerable openings, together with means for automatically depressing said longitudinally-movable cylinder, substantially as described.

4:. A mixing-box for gas-engines comprising an outer casing opening into the cylinderheads with lugs thereon for securing it to said heads, internally-disposed oifsets on said casing, one at the middle and one at the bottom, a fixed cylinder screw-threaded to said bottom offset, a longitudinally-movable cylinder within said fixed cylinder, and means for automatically depressingthe same, each of said cylinders having ports as described and being suitably capped at the bottom; a rotatable cylinder fitting the internal bore of said casing and resting on said. middle offset, corresponding slots in said rotatable cylinder and in the outer casing adjacent a source of gassupply, means for rotating said cylinder from the outside ofsaid casing, a false cap closing in said outer casing and said fixed and longitudinally-movable cylinders, an outer cap with a centrally-disposed opening, and a rotatable disk located in a socket in said false cap, said disk and said false cap having registerable ports, together with means for rotating said disk from the outside, substantially as described.

5. A mixing-box for gas-engines, comprising an outer casing opening into the cylinderheads with lugs thereon for securing it to said heads, internally-disposed oii'sets on said casing, one at the middle and one at the bottom, a fixed cylinder provided with a screw-cap at the bottom and being screw-threaded to said bottom offset and fitting gas-tight within said middle offset, a longitudinally-movablc c vlinder within said fixed cylinder having a cap at the bottom provided with the openings 3, an operating-rod secured to said bottom cap and projecting through the bottom of said fixed cylinder, the spring! between said bottom caps, registerable ports in said fixed and movable cylinders above and below said middle offset of the outer casing, a rotatable cylinder fitting the internal bore of the outer casing, and resting on the middle ofl'set, with means for operating the same from without, registerable slots in said rotatable cylinder and the outer casing adjacent a source of gassupply, an inner cap closing in all said cylinders and havinga centrally-disrmsed socket, a rotatable disk in said socket with means for operating the same from without, registerable ports in said disk and said inner cap and an outer cap, having a centrally-displaced opening, substantially as described.

LAVVRENGE M. JOHNSTON lVitnesses:

W. H. H. ECKI, Buss F. BORNS'IEIN.

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