US2021744A - Internal-combustion engine of the fuel-injection type - Google Patents

Description

Nov. 19, 1935. F. A. PERKINS 2,021,744

INTERNAL COMBUSTION ENGINE OF THE FUEL INJECTION TYPE Filed March 30, 1953 2 Sheets-Sheet l INVENTOR F'. A. PERKINS Nov. 19, 1935.

INTERNAL COMBUSTION ENGINE OF THE FUEL INJECTION TYPE Filed March so, less 2 Sheets-Sheet 2 Patented Nov. 19,1935

i UNITED STATES PATENT OFFICE INTERNAL-COMBUSTION ENGINE F A FUEL-INJECTION TYPE f Francis Arthur Perkins, lieterborough, England, assignor to F. Perkins Limited, Peterborough,

England, a. company Application March-30, 1933, Serial No. 663,509.

In Great Britain Apr 14, 1932 I r 4 Claims. (01. 123-32) This inventionrelates to internal-combustion engines of the kind in which the fuel is injected into the engine througha-fuel-injection nozzle or nozzles during thecompression stroke and 5 which is provided with'a combustion chamber communicating with the engine cylinder through a transfer passage. I It is the object of the present invention to improve the mixing of the fuel and air in engines of this kind.

According to'the present invention the fueland it is therefore advantageous that the charge 7 should'have a swirling 'motion in the combustion chamber.- To this end the-transfer passage may be directed aside from the centre of the combustion chamber at its entry thereto (for example .tangentially to the wall thereof) so that the entering charge is caused to swirl therein. Preferably the combustion chamber .is circular in .form, i. e.,' cylindrical, spherical orgof like shape,

in order to facilitate swirling.

In one construction in accordance with the.

invention the transfer passage. extends through the cylinderhead in an inclined direction upwardly, the combustion chamber is located at the upper en'dthereof, and the fuel nozzle is located in an inclined bore entering the transfer passage from the side thereof. This construction makesfor accessibility of the parts. Preferably the cylinder head is made detachable and the bore of the fuel nozzle is located in the head above the transfer'passage, being inclined downwardly thereto to intersect it.

It may sometimes be desirable to delay the passage of air along the transferfpassage during the compression stroke until fuel-injection commences, as this has the effect of'ensuring that the maximum amount of air traverses the transfer passage during the injection of the fuel. If this is desired a valve is provided according to the present invention in the transfer passage to isolate the combustion chamber from the working cylinder during the beginning of the compression Preferably also it stroke. In one construction the valve is located in the cylinder head'and is mechanically operated to open'during injection of the fuel. Alternatively the valve may be held normally closed by means of a spring and automatically opened 5 late in the compression stroke by the pressure from. the working cylinder, means being provided to hold the valve open until after the end of the working stroke.

The present invention includes internal-'- l0 combustion engines as hereinabove described, wherein (a) a charge of air is partly compressed within the engine cylinder, (b) the air thus compressed-is admitted through the transfer passage to'the combustion chamber, (c) fuel is injected into the passage while the compressed air is passing therethrough to the combustion chain her, and (d) the mixture is exploded in the combustion chamber.

The following is a description by way of example of two constructional forms of internal combustion engine'in accordance with the present invention.

In the accompanying drawings:-

" Figure 1 is a vertical cross-section through the upper part of 'thecylinder and the cylinder head of one formof engine, and v Figure 2 is a similar view of a second form. Referring to Figure l, the enginecomprises a cylinder H in which works a piston l2 and which 9 is closed at the upper end by a detachable cylin der head IS in which a combustion chamber II is formed. The combustion chamber is substan .tially cylindrical in cross-section as seen in the.

transfer passage causes gases which issue therefrom during the explosion stroke into the cylin-. der to impinge upon the piston at an angle.

An inclined bore l6 enters the side of the transfer passage from above and contains a fuel-injection nozzle H. The nozzle is secured in position by studs l8 and nuts l9 and is fed by an oil pipe 28. The nozzle itself is of standard construction such as is readily obtainable in the market, but it is'pierced at its point with two 55 orifices or groups of orifices, one facing up the ,ed by a tube 25 which servestodivide it from a water space 26 and to prevent the outflow of water, in the event of removal of the nozzle for inspection or cleaning.

A cover 21 containing an air inlet manifold 28 is provided over the valve gear. The cylinder head is detachably secured in place by means of studs 29 and nuts 30.

It will be observed that the outer half of the combustion chamber takes the form of a removable cap 33 which is detachably secured by studs 3| and nuts 32, and is not water-cooled. The heat to which this part of the combustion cham- .ber attains during running of theengine, which is less than a red heat, is such as to facilitate ignition of the fuel.

It will be observed that the inclined disposition of the transfer passage serves to bring the combustion chamber into an accessible position at one side of the engine and to facilitate the disposition of the injection nozzle between the stems of the inlet and outlet valves with an accessible rear end to the injection nozzle so that it can easily be removed and replaced. This a matter of considerable practical importance as the nozzlemayrequire cleaning. from time to time.

The length of the combustion chamber l4 in a direction parallel to the axis of the engine is relatively short, that is to say it is smaller than the diameter of the chamber and this permits a chamber to be employed of sufficient diameter to give the fuel a path of considerable length in a circumferential or swirling direction in the combustion chamber. It will be observed that the tangential disposition of the transfer passage causes the gases which are forced into the combustion chamber on the compression stroke of the'engine to swirl as they enter it, and the circular shape of the chamber facilitates the swirling motion.

The nozzle, by directing fuel upwardly into the combustion chamber, causes this fuel to partake in the swirling motion of the air, to be thoroughly mixed therewith, and to occupy a path in the chamber of sufficient length to ensure its complete combustion. At the same time the portion of the fuel which is injected downwardly towards.

the working cylinder attacks the compressed and highly heated air therein before this air is cooled by passage through the neck of the transfer passage. This assists the engine in starting from the cold and further ensures that such air as remains in the main cylinder in the clearance space is utilized for purposes of combustion. Thus more power isobtainable. The nozzle may be constructed so that the main portion of .the fuel passes upwardly into the combustion chamber. v

Referring to Figure 2, this shows an engine which in its main essentials is similar to Figure '1, that is to say there is a cylinder 66, piston I2, transfer passage 55, combustion chamber l4 and ly mixed exhaust valve 2|. There is also an inlet valve and the valve may be operated by over head rockers as described in connection with Figure 1. An additional valve 34 is, however, provided which is capable of closing the-bottom of the 5 sion stroke of the engine but is opened by a rocker of the overhead valve gear, not shown in 15 the figure, when the fuel injection is about to commence after the compression stroke has been partly completed. Consequently the whole .of

' the air which rushes through the transfer passage entrains fuel with it and becomes thorough- 20 with the fuel prior to, as well as during, the swirling operation in the combustion chamber.

In other respects the engine illustrated in Figure 2 operates similarly to that illustrated in 25 Figure 1. I

While the invention has been described with reference to the specific forms illustrated in Figures l and 2, it is to be understood that the in- .vention is not limited to the forms illustrated. 80 In particular the valve 34 could be operated partly automatically by causing it to seat against the pressure and to be held on its seating by a spring which would be forced back as soon as the compression pressure reached a predeter- 35 mined amount. With such a construction the valve would preferably be held open mechanically during the firing stroke. Again, a hot plug, an

electric starter plug, wick holder, or other like device may be provided in a suitable opening in 40 the combustion chamber in order to assist the ignition when starting or running. The fuel nozzle may be arranged to direct the fuel obliquely across the transfer passage so that it impinges upon the opposite wall thereof if de- 45 sired.

1. A compression-ignition engine comprising in combination a working cylinder, a cylinder head and a combustion chamber therein, a trans- 60 fer passage affording communication between the cylinder and combustion chamber and opening tangentially into the said chamber, a fuel injector nozzle recessed substantially flush in a wall of said transfer passage said injector nozzle 55 being arranged to inject part of the fuel along the transfer passage towards the engine cylinder and simultaneously to inject part of the fuel along the transfer passage tangentially into the combustion chamber, and a piston and operative 60 connections to expel substantially the whole of the air from the cylinder into the combustion chamber and transfer passage past the fuel injector on the compression stroke.

2. A compression-ignition engine comprising in 65 combination a working cylinder, a cylinder head and a combustion chamber therein a transfer passage leading from the combustion chamber to the cylinder in a direction inclined to the axis of the cylinder, .said transfer passage leading tangentially into the combustion chamber, a fuel injector nozzle recessed flush in a wall of said transfer passage said injector nozzle being arranged to inject part of the fuel along the transfer passage towards the engine cylinder and simultaneously to inject part of the fuel along the transfer passage tangentially into the combustion chamber, and a piston and operative connections to expel substantially the wholeof the air from the cylinder into the combustion chamber and transfer passage past the fuel injector on the compression stroke. v

3. A compression-ignition engine comprising in combination, a working cylinder, a detachable cylinder head, a combustion chamber. .in said head, a transfer passage in said head. leading from the combustion chamber to thecylinder in a direction inclined to the axis thereof and :opening tangentially into the .combusti'onjchamber, a, bore in the cylinder head above the transfer passage and inclined downwardly opening thereintc',*a fuel injector located in said bore and recessed flush in the transfer passage to inject part of the fuel along the transfer passage towards the engine cylinder and simultaneously to inject part of the fuel along the transfer passage tangentially into the combustion chamber, and a piston and operative connections to expel substantially the whole of the air from the cylinder into the combustion chamber and transfer passage past the fuel injector on the compression stroke.

4. A compression-ignition engine as claimed 10 in claim 3 in which the transfer passage, the bore in the-cylinder head and the central axis of the working cylinder are substantially coplanar and in addition the transfer passage and the bore aforesaid are mutually perpendicular. l5

FRANCIS ARTHUR PERKINS.

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