US1688285A - Carburetor - Google Patents

Description

Oct. 16, 1928.

M. PURvls ET AL CARBURETOR Filed June 29. 1926 CDH Patented @et 16, i928.

MATTHEW. PURVIS AND THOMAS LELE, l QF PLYMUTH, ENGLAND.

CARBURETOR.

Application led June 29, 1926, Serial flo. and in Great Britain May 25, 1926.

rihis invention relates to carburetors for internal combustion engines and has for its object to devise improvements in the construction and arrangement of carburetoi's which will obviate the necessity for any float chamber and choke tubes, ywill render the carburetor simple and cheap to manufacture and easy to'manipulate and control, will facilitate the cleaning of the saine when necessary and will Vlead to anv increase in power obtainable for aA given consumption of fuel, J l

The invention consists in a carburetor for internal combustion engines comprising a :iet tube having` a yplurality of lateral open ings or a slot therein and passing across the air inlet pipe and a movable piston surrounding the jet tube and controlling both the air and liquid fuel supplies simultaneously.

rlhe invention also consists in other details and arrangementsherinafter described or indicated.

The accompanying drawings illustrate two modes of carrying out the invention.

Figure l is a sectional elevation of one convenient form of carburetor constructed in accordance with the invention.`

j Figure 2 is a section on the line 2--2 of Figure l. y A

Figure 3 is a plan of Figure l but showing the piston moved into a position in which the air inlet and fuel jet openings are par tia ly open.

Figure 4 is a sectional view showing a modification of a detail.

ln carrying our invention into eiect in one convenient manner as illustrated in Figures l to 3, we form our improved carburetor with a cylinder a, piston and jet tube c, the whole being' united with the air inlet tube d and being provided with flanges e so that it may be mounted conveniently upon the top of the induction manifold, it being understood, however, that the carburetor may be fitted in any other suitable position and by any other suitable means.

The jet tube c is connected with the inlet f for the liquid fuel supply and passes across the air inlet tube d and in the form illustrated is provided with a plurality of down-V wardly directed openings or apertures y, this direction of the openings'being chosen'in the form illustrated which is adapted to be mounted upon the top of the induction manitine spray giving perfect acceleration while at the Asaine time overcoming the diiiicultyr experienced when starting cold sincev no priming will be necessary.

, iiny other suitable arrangement of the apertures may be chosen, however, depending upon the location of the carburetor, and,

moreover, it will be understood that in place oi' such apertures we may adopt one or more longitudinal slots in the wall of the jet to replace the apertures or sets of apertures (when more than one set is employed).

The piston o is adapted to surround thejet tube in a fluid-tightmanner and is con- 'trollable by any suitable Bowden wire or other actua-ting gear connected with the shank or extension 71, of the piston, the arrangement being such that when the piston is moved towards the right looking at Figure l the air inlet and the fuel jets will be gradually opened to an extent determined by the extent of movement of the piston so that thereby the air and fuel supplies will be simultaneously controlled and the proper mixture ratio maintained under all condi tions of working.

` Moreover since the piston surrounds the jet tube in a i'iuidtight manner and cont pletely closes the fuel jets and lair supply tube when in the position shown in Figure l no float chamber will be needed thus conducing to simplicity and cheapness of con-` struction and eliminating any float feed which is often a source of trouble.

ln the form shown in Figure l the fluid Y of the piston round the jet tube is obtained by means of a split bush z' surrounding the jet tube and arranged within the cylinder, such split bush having its parts 'held together by means of springs 7c which also serve to control a. split sleeve Z round the piston so to press the same tightly against :die walls of the cylinder and thus maintain iiuid tightness of the piston within its cylinder.

ln an alternative form of fluid-tight connection in accordance with the invention illustrated in Figure 4 the iet tube is surrounded by a split bush z" having its ends coiled or bevelled so that the parts may be pressedntogetlier by means of a spring m at one end and a plate it screwed to the piston at the other end, the outer sleeve Z being maintained in fluid-tight contact With the cylinder Wall by means of the springs k which in this case however need not press upon the inner bush.

l Wle ind that very satisfactory results may be obtained from our carburetor when the saine is combined With any suitable air heating system by which the incoming air may be heated either by the exhaust gas from the engine or otherwise.

Ne Wish it to be understood that the invention is not to be confined to the foregoing details of construction which are given purely by Way of illustration and not of limitation since We may vary the form of our jet tube and its locationttvhether vertical, horizontal or inclined) and We may also vary the vmeans adopted `'for *maintaining fluidtightconnection between' the jet tube and con-trolling piston surrounding the rsame as also the means adopted for actuating` the piston Vdepending upon any particular practical requirements that may have `to 'be fullilled;

Having nonT described our invention *what We claim as new and desire to secure by Letters Patent is :--V y l. A carburetor for internal combustion engines comprising in combination a jet tube through which the fuel may issue laterally, an air inlet pipe lacross Awhich said jet tube extends, a piston surrounding said jet tube, a cylinder Within which said piston is slidable and an axially split sleeve surrounding said piston and making` fluid-tight contact with the Wall of said cylinder.` I

2. A carburetor for internal combustion engines comprising lin combination a jet tube trom Whichtuel may issue laterally, an air inlet pipe yacross which said jet tube extends, a piston oo-axialcxvith said jet tube, a cylinder Within which said Apiston is slidable,

a split sleeve surrounding said piston7 a splitv bush surrounding said jet tube and enclosed by said' piston and springs interposed between said split bush and said split sleeve.

In testimony whereof We have signed our names to this specification.

l MATTHEW PURVS.

THOMAS LEE.

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