US1666892A - Apparatus for regulating mixture formation in carburetor systems - Google Patents

Description

April 24, 1928.

. ,w. E. ERNST APPARATUS FOR REGULATING MIXTURE FORMATION IN CARBURETOR SYSTEMS Filed 0012.6 1925 2 Sheets-Sheet l jwen for Mike/n1 bar are! Ems? fil /0mm, I

April 24. 1928.

W. E. ERNST APPARATUS FOR REGULATING MIXTURE FORMATION IN CARBURETOR SYSTEMS 2 Sheets-Shet 2 Filed 0012.6, 1925 in mm fur Mme/m befihard ,5 P115 1 [oer ff f/ome 1 air. A no-load passage 7 is fitted in the usual way to the first throttle valve 3 in the direction of flow. (Arrow 8.)

a As regards Figure 2, the side walls 10 an 11 of a rotary value are used in a casing 9 as throttle organs. The position of this valve is shown in full lines with a comparatively small opening, whereas the dot and to dash lines'10-and 11 show the position at full opening. It will be seen from the draw- ""ingthat when the rotary slide valve is fully open, by narrowing the cross-section of the assagcs, both on entering and also on leav- 16 mg the rotary slide valve, the throttling effects can be maintained. The supplementary air is here admitted, by way of example,

through an opening 12 made in the. cover plate of the slide valve. This opening is controlled by an opening 13 in a cooperating plate 14 of any desired design. The full lines show exactly how the orifice 12 is opened and a quantity of extra air is admitted. The dot and dash opening 13- shows how, on full opening of the throttle organs 10 and 11, the full opening of the orifice 12 is alread exceeded, whilst only a small quantity 0 extra air is admitted.

This arrangement is designed to work with medium throttle openings and with a specially economical mixture, under the heaviest load of the motor, and to give a high efliciency result. With this object the plate 14 is placed between the slide valve and the 5 cover of the casing and held in position by the pressure of a spring. The stop of the plate is conveniently placed in the casing cover and can, with advantage, be made adjustable or regulated from the operators seat. This arrangement permits adaptation of the added supplementary air for various kinds of fuel and heat conditions of the motor. a

The dot and dash lines 15 and 16 show how the space between the throttle organs may be enlarged to bring the pressure in the throttle chamber into closer relationship with the atmospheric pressure. One or more passages 15 or 15 may, by way of example, be provided in the wall 10 for the draining of the mixture from the throttle chamber into the no-load section.

.In the form of execution, according to Figure 3, the inlet of the supplementary air into the space between two throttle valves 17 and 18 or any other desired throttle organs is controlled by a slide valve 19. The working of the slide valve is effected by any desired means as, for instance, an eccentric 20, which works on a flange 21 on the slide valve, whereby a spring 22 kee s this slide valve always against the eccentrlc. In place of the eccentric, of course, any other similarly acting device may be used, such as curved-discs and the like.

With a special form of execution a wedgeshaped ring 23 is provided which acts. on the shaft 24 of the eccentric and can move this shaft in an upward direction. The object of this arrangement is, for example, when working with a cold motor to admit less supplementary air than when working with a warm motor, thereby retaining, in both cases, the due degree of opening of the slide valve produced by the eccentric or the curved disc.

In the example, according to Figure 4, a conical throttle organ 26 and a similarly de-. signed throttle organ 27, following the stream line, are provided in a conical casing 25, the whole constituting a throttle chamber 28. The inclination of the casing walls 29 in the length of stroke of the throttle organ 26 is, in this case, different from the inclination of the casing walls 30 in the length of stroke of the throttle organ 27. The eliect of this is that the opening of the throttle organ 26' is always greater than the opening of the throttle organ 27.

The fuel for the operation without load is admitted, in the usual way, through an opening 31. The throttle bodies may, of course, be constructed in a stream line shape.

In the example, according to Figure 5, a boring out, or the like 34 m a housing 32 in the course of the inner walls 33 of this housing was effected whereby a sharp reduction 35 resulted. At a distance from the same there are openings 36 made for the supplementary air, which are controlled in .an desired way, as, for example, by a slide va ve 37 Throttle valves 38 and 39 are provided, as in Figure 1. By this arrangement the introduction of the supplementary air into the throttle chamber is made dependent in greater measure upon the number of revolutions of the motor, because, in this case, a particularly pronounced injector action of the mixture flowing through the housing takes place. By this special construction, an extension of cross-section is simultaneously produced in the throttle chamber itself, which, in many instances, has afavourable efiect.

In the forms of execution described foregoing, it is understood that, in the case of the two throttle organs in the stream line of the mixture, thethrottle organ lying first in the direction of flow always exercises a lesser throttling effect than the following .throttle organ in the direction of flow.

r 1n the ill a lever 43. The throttle valve 41, on the 'contrary, has a shaft 44 which can rotate opposite to another constructional part 45, also of desired design, which part is controlled by a lever 46 and a guide 47 in dependence upon the lever 43 of the other throttle valve. An arm 48 is fixed to the valve 41, which arm, under the action of a spring 49, impinges on a stop 50 and keeps the throttle valve 41 slightly open. it the other throttle valve 40 is closed or is in the no-load position. 011 the part 45 a further arm 51 is fixed, having a stop 52. The latter can be so adjusted that, on the oscillation of the two levers 43 and 46, the throttle valve 41 only sets up a corresponding oscillation when the throttle valve 40 shows a larger-opening than the throttle valve 41, as may be seen by the dot and dash linein 40.

The effect or this arrangement is that when the throttle valve 40 is in the no-load position the throttle valve 41 is always open, sothatthere is always a sutlicient depression at a no-load nozzle 53 which ensures the plassage of the fuel through the no-load nozz e.

Another efi'ect of this arrangement, simultaneously realized, is that the passage from the no-load nozzle to the main nozzle is extremely uniform and gentle, inasmuch as, by approximation of the depression in the throttle chamber to the atmospheric pressure, the delivery from the no-load nozzle is compljeted at the right time'if the main nozzle has taken up the correct supply of fuel for the composition of the mixture.

A similar result is achieved with the rotary slide valve, as may be seen in Figure 2, through the passages 15fand 15".

In the term of execution, according to Figure 7, a throttle valve 55 and a lever body with three lever arms 56, 57 and 58 are rigidly fixed to theshaft 54. The lever 56 is intended to im inge against a set screw 59 in the wall of the carburetor or of a stud attached thereto. thus giving the minimuin opening to this valve, such opening being necessary for the attainmentof the requisite depression in the throttle chamber. On the shaft 54 of the throttle valve 55 an accelorator lever 60, loosely rotatable, is fitted, which is served, in the usual manner, by a tension member 61 and is held by a spring 62 or other means as against the action of the tension member. A head piece 63 is fitted to the accelerator lever, which lies within the range of a set screw 64 or 65 in the lever arms 56 and 57. The last named arm is connected to the head 63 by a spring 66.

By this arrangement, the throttle valve 55 is kept in theminimum opening position by the pull of the accelerator spring 62 and the stop of the arm 56 against the set screw 59,

counterbalancing the action of the spring device 66.

The operation of the accelerator tension member 61 oscillates the accelerator lever in certain measure and it is only after impinging against the set screw that the throttle valve 55 is brought to a further opening. 7

The shaft 54 of the throttlevalve is connected with the shaft of the other throttle valve by levers and a connecting rod, similar to the way indicated in Fig. 6, so that the other throttle valve begins its movement at the commencement of the pull in the accelerator tension member; the throttle valve 55, on the contrary, only begins the opening movement and then further participates when the head-piece 63 impinges against the set screw 65.

Instead of only two throttle organs several mutually controlling throttle organs may, of course, be used in the same circumstances. The throttle organ may either form a part lot the carburetor or serve as an adjunct to same.

Figure 8, by way of example, shows such an arrangement wherein three throttle organs or valves. 67, 68, and 69, are provided. These three throttle organs or valves are positively connected one with the other and controlled so that each succeeding throttle organ or valve, proceeding from the carburetor point 70, provides a smaller opening than the preceding throttle organ or valve. Such a carburetor is fitted in the usual mannor to the motor block 71.

Figure 9 illustrates another arrangement wherein a suction conduit 74 is provided be tween the mixture forming place 72 and the openings 73 leading into the cylinder cham bers ofthe motor. Between mixture forming place 72 and openings 73 are arranged throttle organs or valves 75 and 76, so connected with each other that a larger opening is provided by the valve 75 than bythe valves 76. If desired, another throttle organ or valve77 may be provided, as indicated in dot and dash lines in Figure 9. In this case, also, the plurality of throttling organs or valves 75, 77, and 76,? respectively provide successive smaller openings for the flow of the fuel mixture from the main mixture forming place 72 to the openings 73 leading into the cylinder chambers'of the motor.

- Even in the case of over pressure of the two throttle organs, from the commencement of the load on, are not. opened to the sameextent. for instance, at the same throttle valve angle, but that the throttle organ coming first in the direction of flow of the mixture, outpaces the other throttle valve. 'lhereby the measure and the extent of the advance (an increasing and, in a given case. a decreasing advance) is suitably adapted to the existing conditions in the machine, in the sense that the nearest possible approximation to the atmospheric pressure is attained in all phases of working.

What I claim and desire to secure by Letters Patent of the United States is 1. In combination with the intake conduit of an internal combustion engine, a pair of throttle valves in said conduit spaced from each other to define a mixing space, and unyielding connecting means between said valves holding them at a fixed angular relation to each other so that a change in the degree of opening of one causes a corresponding change in the degree of opening of the other. the valve positioned nearer the motor being at all times inclined to the axis of said conduit to a greater extent than is the other valve.

2. Tu combination with the intake conduit of an internal combustion engine, a pair of throttle valves in said conduit spaced from each other todefine a mixing space, unyielding connccting means between said valves holding them at a fixed angular relation to each other so that a change in the degree of opening of one causes a corresponding change in the degree of opening of the other, each of said valves being adapted when in closed position to substantially close the conduit. the valve positioned near the motor being at all times inclined to the axis of said conduit to a greater extent than is the other valve, and means limiting the angular movement of said valves.

3. In combination with the intake conduit of an internal combustion engine, a pair of throttle valves in said conduit spaced from each other to define a mixing space, unyield ing connecting means between said valves holding them at a fixed angular relation to each other so that a change in the angular position of one causes a corresponding change in the angular position of the other, a conduit for supplemental air opening into said mixing space. and means controlled by the movements of said valves for opening and closing said last mentioned conduit.

4. In combination with the intake conduit of an internal combustion engine, a pair of throttle valves in said conduit spaced from each other to define a mixing space, unyielding connecting means between said valves holding them at a fixed angular relation to each other so that a change in the angular position of one. causes a corresponding change in the angular position of the other, the valve nearer the motor being at all times inclined to the axis of said conduit to a greater extent than to the other. the wall of said conduit being provided with a port for admitting supplemental air to said mixing space, and means controlled by the movements of said valves for opening and closing said port.

5. In combination with the intake conduit of an internal combustion engine, a pair of throttle valves in said conduit. each valve being adapted to substantially close the conduit to control the flow of fuel mixture through said conduit, said valves being spaced from each other to define a mixing space. unyielding connecting means between said valves holding them at a fixed angular relation to each other so that a change in the angular position of one causes a corresponding change in'the angular position of the other, the-valve neare the motor being at all times inclined to the axis of said conduit to a greater extent than the other, the wall of said conduit being provided with a port for admitting supplemental air to said mixing space, means controlled by the movements of said valves for opening and closing said port, and a no-load air passage leading to said mixing space.

' WILHELM EBERHARD ERNST.

Images