US1208998A - Internal-combustion engine. - Google Patents

Description

A. J. MACKAY.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED NOV- 28. I913.

Patented Dec. 19, 1916.

2 SHEETS-SHEET I.

I INVENTOR BY a ONY A. J. MACKAY. INTERNAL comausnou ENGINE.

APPLICATION FILED NOV- ?B. 913.

Patented Dec. 19, 1916.

2 SHEETS-SHEET 2- Fig. 5.

wmx'asszs & a. a.

UNITED STATES PATENT OFFICE.

ALEXANDER JAMES MAGKAY, OF BOURTON, ENGLAND, ASSIGNOB OF ONE-HALF TO DONALD NORMAN DODSON, OF WHETSTONE, ENGLAND.

INTERNAL-COMBUSTION Enema.

Specification of Letters Patent.

Patented Dec. 19, 1916.

Application filed November 28, 1913. Serial No. 808,485.

To all whom it may concern:

Be it known that I, ALEXANDER Jams MACKAY, a subject of the King of Great Britain and Ireland, residing at Adcroft House, Bourton', in the county of Dorset, England, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention relates to internal combustion engines and more articularly to those of the Diesel and semiiesel types in which air is compressed to a relatively high pressure com ared with that obtaining in ordinarygxp osion engines, and the fuel is then injected into the cylinder or a chamber communicating therewith.

The object of the present invention is to provide an improved construction of cylinder head and neighboring fparts whereby an improved arrangement '0 jet chamber is provided with a view to obtaining more perfect scavenging of these parts, more perfect combustion after injection of the fuel, more certain ignition on light load and greater economy of fuel, and also in the case of a semi-Diesel engine to provide for an improved arrangement and mounting of the hot bulb, whereby it may retain its heat, be

readily heated and also whereby it may be easily removed for cleaning purposes.

With these ends in view the principal feature of the present invention lies in the provision of a cylinder head having a cavity therein communicating along one side wit the cylinder and preferably taking roughly the form of an inverted U with bul 'ng sides in cross section, which cavity may orm with the upper end of the piston or a part carried thereby, a tubular space, at one end of which the fuel inlet jet is located. The cavity is preferably arranged so that gravity aids the passage of the fuel along the cavity. This is considered an important feature for the reason hereafter set forth.

The cavity is preferably tapered slightly along its length so that the fuel inlet et is arranged at the smaller end thereof, the

widening of the cavity from this point allowing of spreading of the fuel after leaving the jet. In the case of a semi-Diesel engine in which the compression temperature of the compressed air is not relied upon for ignition but a hot bulb or surface is employed, this surface or bulb is arranged at the end ing washers as hereafter described so that it may be readil heated and when once hot will retain its eat. I

Reference will now be made to the accompanylng drawings which show two convenlent modes of carryin the invention into effect in connection with two stroke cycle horizontal and vertical engines of the semi Diesel type in which a. hot bulb or its equivalent is used to aid i nition of the fuel.

In the drawings, igure 1 shows in longitudinal cross section the cylinder head of a horizontal engine to which the invention is applied. Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1. Fig. 3 is a sectional view taken in the same lane as Fig. 2 but showing the inlet and ex aust ports and the piston at the outer end of its stroke. Fig. 4 1s a cross sectional view through the inlet and exhaust ports in Fig. 3, while Fig. 5 is a view similar to Fig. 1 but showing by way of example how the invention may be applied to a vertical engine. Fig. 6 is a devcloped side view of the ports in the cylinder wall which may be conveniently adopted.

Referring more particularly to Figs. 1 to 4 of the accompanying drawings, a indicates a portion of the cylinder wall, 6 indicates the cylinder head which is shown as a se arate casting, which it will be understood is suitably bolted to the cylinder, while a indicates the piston. The cylinder head is pro vided with a cavity (5 which in cross-section is in the form of an inverted U with bulging sides, that is to say the cross-section corresponds substantially with that of the outer cover of an ordinary pneumatic tire. This cavity is tapered longitudinally, one end being of greater diameter than the other.

n the form shown the cavity though generally of tapering formation hasnot a uniform taper, but as will be seen the rate of the taper is greatest near the smaller end after which the rate of increase of the size of the cavity becomes less toward the larger end. In the cavity shown in Fig. 5 this formation is more pronounced and in this case the cavity, though of greater diameter at the inlet end, has actually its largest dimensions near the middle. In the narrow end of the cavity the fuel inlet jet 6 is arranged so that the fuel may enter the cavity an the end of the piston a and be sprayed along the length thereof toward the wider end. In the latter end of the cavity and opposite the fuel jet an opening is provided communicating with the ignition bulb f which is preferably seated between non-conducting soft washers g and kept in place by a suitable clamping evice such as the ring it which is situated behind the bulb as shown. By this means the bulb is easy to heat and retains its heat better when the engine has been started and the blow-lamp or the like used for initial heatin of the bulb has been extinguished. Besi es this the bulb, it will be seen, me be easily removed for cleaning and provl es 9. ready means of cleanin the combustion chamber as most or all 0 any unburnt fuel or residue remains in the bulb.

The axis of the cavity d is preferably arranged substantially vertically or at a substantial angle to the horizontal and so that the fuel inlet-end is at the higher level. By these means we insure that the fuel may properly traverse the cavity even when the guantity of fuel admitted is small, since the uel is aided by gravity. Further it is thus insured that the fuel, however small in amount, will reach the hot bulb and thus keep the same hot. Certain ignition is thus obtained even on light load and there is a minimum of waste. In the case of a horizontal engine the above mentioned disposition of the cavity may be readily obtained by arranging the same at right angles to the axis of the cylinder and with the fuel inlet at the top. This arrangement is clearly shown in Fig. 1. In the case of a vertical engine a similar eflect may be obtained by inclining the jet chamber or cavity with respect to the axis of the cylinder as will be presently described in connection with of the drawings. i

haflle member is provided. in the form of a transverse rib 2' which extends into the open bottom of the cavity in the cylinder head when the piston is at the inner end of its stroke, the sides of the rib being sloped toward the apexof the rib which may be substantially straight and hence substantially. at right an les to the axis of the cylinder, considering t e case of a horizontal engine. One side of the rib, viz: that which is on the same side of the engine cylinder as the exhaust port In in the cylinder walls, is gently sloped as at 7' while the opposite side is sloped abruptly as at Z.

In the side of the cylinder wall con'esponding to this latter abruptly sloped side of the rib on the piston, the air inlet port m is provided; the arrangement being such that when the end of its stro e air entering the cylinder will be directed upwardly by the abrupt wall of the baiiie member into one side of the cavity in the cylinder head, sweeping the iston is at or near the outer ignition space is thus insured. The path of the air when thus scavenging the cylinder and cavit d is shown by the continuous arrows in ig. 3. It will be seen that the end of the abruptly sloped side or wall Z of the rib z is slightly turned over at 1' toward the wall of the cylinder, thus insuring that the air will be'directed in the desired manner.

When the piston is at the inner end of its stroke the rib thereon enters the open portion of the cavity in the cylinder head and as previously mentioned a tubular space is thus formed as shown in Figs. 1 and 2.

Referring to Fig. 5 which shows by way of example how the invention may be a plied to an engine having a vertical or (iiagonal cylinder without sacrificing the help of gravity in aiding the pasage of fuel to the bulb,"the cavity (1 is here shown as inclined at a substantial inclination and with the jet e at the upper end. The cylinder head I; inclosing the cavity or chamber d is in this case shown as being integral with the cylinder but it may of course be made as a separate element. In order that the baflle member 2' preferably adopted upon the cylinder as before may inclose a tapering tubular space, it is, in the example shown, sloped to'correspond with the slope of the cavity :3. Otherwise the bafile member is similarly formed and performs the same functions as that already described in connection with Figs. 1 to 4. I a

It will be understood that it is not essential toprovide an inclined cavity as just described. If such a cavity is not desired the cavity may merely be arranged as in Fig. 1,

so that its axis is substantially at right angles to the cylinder.

. n order that the top of the piston and baflle member may, when at the inner end of the stroke, form as perfect a tapering cavity as possible, it will be seen 4 which shows the piston head in plan, that the rib with its sloping side j forms a tapering trough, one wall of which (viz: that on the inlet port side) is higher than the other, (see Fig. 2). To conform to the-she of this trough and the shape of the cavlty d the inlet and exhaust openings are arranged as shown in Fig. 3, so that they extend around the cylinder nearer one another upon the side thereof, in line with the smaller ends of the trough and cavity. That is the distance between the ends of the ports at s, t is less than at u, o. This arrangement has an advantage in that the larger beari surface between a and '1: may be arrange on the side of the cylinder which takes the thrust. This is a feature of importance since some types of engine wear badly adjacent the'ports if these are on the thrust from Fig.

side of the cylinder, since the ports scrape the'oil oil the piston on the side where it is -most needed.

In place of employing ports as shown in Fig. 4, which are parallel to the axis of the cylinder, the ports ma be conveniently arranged diagonally as own for example in the developed view'shown in Fig. 6, where it will be seen that the orts on each side of the central port are inclined. Such an arrangement has the advantafge of providing a better bearing surface or the piston and also we consider an easier path for the scavenging air.

- In operation the fuel entering at the small end of the tubular space travels down or along the space and part enters the ignition bulb which causes this portion to lfllt9, the flame so produced being reflected a igniting the remainder of the fuel as it enters.

Theignition cavity with'the fuel inlet at one end thereof and which preferably tapers outwardly from this end is also applicable to an engine of the ordinary Diesel type though in this case, of course, the ignition bulb will not be required.

It is to be understood that the invention is not limited to the exact detailed arrangements described, as modifications may be made within the spirit of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is V 1. In an internal combustion engine, a cylinder, a combustion chamber arranged across the end of the cylinder, said combustion chamber having a cavity which tapers gradually alon its length so that one end is of greater iameter than the other, an opening along one side of the chamber for afiording communication between the cavity and the cylinder,'a piston in said cylinder having a trough shaped end portion which is tapered to corres ond with the taper of the cavity and whic when the piston is at the inner end of its stroke, serves to close ck and the opening between the cavity" and the cylinder, and means for admitting fuel at the smaller end of the ta ering tubular s ace formed by the cavity an the said end 0 the piston, so that the fuel may be sprayed along said 5 ace-toward the lar er end.

2. n an internal com ustion engine, a c linder, a tapering elon ted combustion c amber disposed lengthwise across the end of the cylinder and communicatin therewith along one side, means for a mitting fuel at the smaller end of the combustion chamber and-ignition means at the larger end thereof facing the fuel inlet.

3. In an internal combustion engine, a cylinder, :1. cylinder head having an elongated cavity therein tapering longitudinally and disposed lengthwise across the end of the cylinder, said cavit communicating along one side with the cy inder, a piston in said cylinder having a tapering trough shaped portion which, when the piston is at the inner end of its stroke, servesto close the said opening and completes the tapering cavity so as to rovide a tapering tubular space in the cylinder head, means for admitting fuel at the smaller end of the space so formed, and ignition means at the larger end of the cavity.

4. In an internal combustion engine, a cylinder, a tapering elongated combustion chamber disposed lengthwise across the end of the cylinder and communicatin therewith along one side, means for a mitting fuel at the smaller end of the combustion chamber and i itionmeans at the larger end thereof facing the fuel inlet, the end of the chamber at which the ignition means are arranged being lower than the end at which the fuel is admitted.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ALEXANDER JAMES MAOKAY.

Witnesses:

- D. W. DoesoN,

P. A, DUTHUAITE.

Images