US2944646A - Carburettor vacuum control device - Google Patents

Description

July 12, 1960 v. G. WILLMER cARBuRETTo VACUUM CONTROL DEVICE Filed June 6, 1957 VICTOR GEORGE WILLMER BY am a 66W ATTORNEYS Decisive? Par fi iQ 73 c v QCARBURETTOR VACUUM CONTROL DEVICE Victor George Willmer, Toorbul, via Caboolture,

Queensland, Australia Filed June 6, 1957,Ser. No. 664,011

Claimspriority, application Australia June-8, 1956 2 2 Claims. (Cl.l192-'-3) This invention relates to improvements in and relating to vacuum control devices for use with carburettor's of vehicle internal combustion engines. I V

The operation of a carburettor of a car or motor cycle depends upon partial vacuum in the intake manifold which acts to draw the fuel from the carburettor ,jet.

However, there is the disadvantage that when .t'he'engine v wastage of .fuel, as well asi the, .deleterious effects .men

tione'd... i i; I Accordingly, my present invention has been-devised to overcome these disadvantageaand it hasfor itsprincipal object the provision of a device for attachment to or incorporation in the constructionof a carburettonand which is adapted to begbrought intooperation to elimi nate or.considerablyreducethe vacuum. exerted on the carburettor when the engine is-abeing usedasyabrake or over-run. v

Another, object of the invention :is to provide-a device of the character described which may be used, .ifdesired,

-togovern the driven speed of .a vehicle withoutacting toreduce the efi'iciency of the vehicle at speeds up to a predetermined speed.

-.Further objects of the'inventionare tojprovide a device. .of the aforestated nature "which is relatively simple and inexpensive to .manufacture and to instalin, a vehicle, and which will prove veryefficient, trouble-free .an'cLdurable in operation;

Otherobjects and advantages will :be "apparent from 'the following description. 1

- In the drawings:

Figure lis a sideelevational'viewof a'device according to my; invention, shown fitted to acar engine," part of which'is indicated-in brokenoutline; a

v Figure 2 is a half-sectional,elevational'view of :part the device shown in Figure 1; and e a ,Figure 3 is a plan viewalongth'e line 3-3 ofjFigure 2, :With certain parts omitted. I 7 r The vacuum control, device shown in the drawings in- V ,cludes a hollow body 10 which ismore or less T-shaped inplan view, an extension '11 of the body 10 being formed with registeringapertures 12 at top and bottom. "The said extension 11 is adapted to be'fitted between the '"carbur'ettor 13 and the intake manifold 14 of the vehicle engine; thefa'pertures 12 communicating with the car bure'ttor and intake manifold.

The mainiportion of'the bodylll has formed through its upper face a round opening 15, the periphery of which 'forms a vacuum break valve seating- 16 upon which provided with a downwardly extending stem 18; verti: cally movable in a valve stem guide 19 formed in the lower part of the body 10.

Over the main portion of the body 10 there is removably fitted a cover 20 having a gauze-covered air inlet 21 at its front and an opening 22 at its top defined by an annular upstanding flange 23. Mounted on the cover 20 centrally over the opening 22 thereof is an actuating-valve housing 24 formed as upper and lower portions 25 and 26 connected by screws and sealed from one another by an interposed valve diaphragm 27. To the bottom of the diaphragm 27 there is centrally secured an actuating rod 28 which passes down through'a central aperture 28a in the base of the lower portion 26 of the housing- 24, through the opening 22 of the cover 20, and through an oversize aperture (notshown) in one end of a lever arm 29, a washer 30 and split pin 31 being provided on the lower extremity of the'actuating rod 28 beneath thesaid end of .the lever arm 29. The other end of the lever arm29 is pivoted in a bifurcated bracket 32 secured to the side of the cover 20, while an intermediate part of the leverarm 29 is pivotally connected to a pivot lug 33 extending up from the centre of the vacuum break valve 17. v

A vacuum tube 34 is provided to connect the body 10 to the upper portion 25 of the actuating-valve housing 24, and this tube 34 has its ends secured in nipples 35 screwedinto tapped apertures 36 and-37 in the body 10 and in the upper portion 25 of the actuating valve housing 24 respectively. Further tapped apertures 38 and 39 are provided in the top portion 25 of the actuating- =va'lve housing 124 for'j the connection of control tubes "leading to acceleraton-Iclutchand dash-board connections.

5 The tapped aperture 39, has screwed therein a nipple 40 from which there leads a control tube 41 to .a-clu'tchactuated -air valve '42- mounted by meansliof a mounting bracket 43 onthe side of the engine. This airvalveais of a known type inwhich an air inlet 44 is normally maintained closed but maybe opened when 'any degree I of inward movement is imparted to a spring-loaded stem -or plunger. 45 by means of a pivoted lever 46, vthelatter :being connected in this case-to an actuating rod '47 'leading to the vehicle clutch (not shown) land adapted to'be moved in the-direction indicated by the arrow 48'whenever the clutch pedal, is depressed. Thus the upper'po'rfar'as' the tube'41 is concerned whenever the clutchis in normal released driving position, as will be the case when the engine isbeing used as a brake or over-run.

CWithin the tapped aperture 38 of the actuating-valve housing 24 there is screwed a T-shaped tube 49 of which one arm 50 is secured to an air inlet tube 51of lesser diameter. To the threaded outer end of th'e'air inlettube 51 there is s'ecuredby means'of'locknuts '52 onearrrft tif .a -U-shaped spring steel valvemer'nber 53 the other arm of which passes-the open-end of'the air inlet*t1'1 be'51 "and has a rubber pad 54 held in place by a metalplate 55. A central aperture (not shown) in the plate 55"al- 'lows' the-open end of the air inlet tube 51 'tob'earjagainst i the rubber pad '54 when'the outer arm of 'theyvalvelmem "there-normally seats a-vacuum break valve 1'] which -is ber 53 is moved towards the air inlet tube 51, andfor this purpose, the saidarm of the valve member 53 is co'nnected by a tension spring 56 to a cable 57 extending to the dash-board indicated at 58 of the vehicle for. operation by a controlknob 59." Thus the air inlet tube 51 will normally vent to atmosphere the upper portion zs-orthe valvehousing 24,'but it'may be closed whenfdesired b y pulling the knob 53 to cause the valve memberSS't seal the end-of thegtube 51, the-tension spring 56 aeting toen- I sure that no undue=strain wil1. be placed on the valve 2,944,646 Patented July 12,1960

member 53 by forceful pulling of the knob 59 and cable 57.

The T-shaped tube 49 has its other arm 60 connected to one end of a control tube 61 leading to an externally: threaded. connector tube 62 mounted on the engine by means of a mounting bracket 63. To the connector tube 62 is secured an air inlet tube 64. of lesser diameter pro vided with a valve member 65 similar in nature to and mounted in the same manner as the aforedescribed valve member 53, the valve member 65 tending normally'to maintain its sealing arm clear of the open end of the .air inlet tube 64. However, this valve member 65 is arranged so that it will be held against the end of the air inlet tube 64 when the accelerator (not shown) of the vehicle is released or inoperative, and to be clear of the air inlet tube 64 only when the accelerator is pressed; To this end, an actuating rod 66 from the accelerator is pivotally connected to an arm 67 of a lever member which has another arm 68 connected by a pivoted throttle-operating rod 69 to the fuel-control mechanism (not shown) of the carburettor. A control screw 70 is mounted by means of a bracket 71 on the lever arm 67 so that when the accelerator is inoperative or released the screw 70 will bear against and urge the valve member 65 into closed position on the air inlet tube 64, but when the accelerator is pressed to move the rod 66 in the direction indicated by the arrow 72 the screw 70 will immediately move clear of the valve member 65 to cause the control tube 61 to vent to atmosphere the upper portion 25 of the valve housing 24. V

In order that this opening of the air inlet tube 64 will take place before the fuel-control mechanism of the carburettor is operated by the rod 69, the latter has its upper end mounted slidably in a guide bracket 70a on the lower end of a rods 71a leading to the fuel-control mechanism, the rod 69 being held normally by a compression spring -72-so that a nut 73 on its upper end will be spaced from a top plate 74 of the guide bracket 70a. When'the rod 66 is moved upon depression of the accelerator, the valve member 65 will immediately move to open theair inlet tube 64, but the rod 69 will move a short distance against the action of the spring 72 before its upper nut 73 will strike the top plate 74 of the guide bracket 70a to cause the rod 71a to operate the fuel-control mechanisnythe -usual return spring (not shown) of the fuel-control mechanism being of greater tension than the spring 72 so that the above action will take place.

In the operation of the device, it will be apparent that the body 10 is subjected to vacuum within the carburettor and intake manifold, and it is required that the vacuum break valve 17 be raised when the engine is being used as a'brake or over-run. As the vacuum tube 34' connects the body 10 to the upper portion 25 of the actuating-valve that the diaphragm will be raised by the carburettor vacuum if the apertures 38 and 39 are closed to atmosphere, so that the rod 28 will move the lever arm 29 to raise the .larly, the accelerator-controlled valve member 65 will be acting to close the air inlet tube 64 when the accelerator .is in the released position of over-run, so that the aperture 38 will be closed to atmosphere as far as the tube 61 is concerned. 'Provided then the knob 59 of the cable 57 is pulled to close the valve member 53, the chamber withinthe upper portion 25 of the actuating-valve housing 24 .will be closed to atmosphere and the diaphragm 27 will be moved to raised position as a result of the connection to the engine vacuum by the tube 34 so that the carburettor vacuum will be broken.

If at any time during over-run, it is desired to restore the carburettor vacuum, either the. accelerator may be :housing 24 above the valve diaphragm 27, it will be seen pressed to open the valve 65, or the clutch pedal may be depressed to open the valve 42, or the knob 59 of the cable 57 may be released to open the valve 53. In any one of these cases, the chamber above the diaphragm 27 will be vented to atmosphere so that the vacuum through the tube 34 will lose its effect on the diaphragm 27 and allow the vacuum break valve 17 to return to closed position.

The device lends itself to the use of a governor device of any known type associated with the transmission of the vehicle or a wheel thereof, the governor being connected by a suitable cable to the valve member 65 so that when the vehicle reaches a predetermined speed the valve member65 will be moved to close the air inlet tube 64 even though the accelerator will be pressed. As the clutch will be in released position at this stage, the diaphragm 27 will be moved to open the vacuum break valve 17 provided the knob 59 is in withdrawn position. Speed governing means of this character will be found to be very advantageous in that the performance of the vehicle engine below the predetermined maximum speed will not be impaired in any way.

While devices made and used in accordance with my invention will be found very effective in achieving the ob,- jects for which the invention has been devised, it will be understood that the particular exemplary embodiment of the invention hereinbefore described may be subject to many minor modifications of constructional detail and design which will be readily apparent to persons skilled in the art without departing from the scope and ambit of the invention as defined by the appended claims.

What I claim is:

1. In combination with an internal combustion engine having a carburettor, an intake manifold, and an accelerator control for the-carburettor; a control device entirely vacuum-operated free of the speed of said engine for reducing the vacuum on the carburettor during periods of engine-braking or vehicle over-running, said control device including a chamber connected in communication with the carburettor and intake manifold, said chamber having an inlet for atmospheric air, a'vacuum break valve normally closing'such inlet, means responsive solely to vacuum conditions extantwithin said manifold for opening said valve to admit atmospheric air to the chamber to neutralize vacuum in the carburettor and intake manifold, alost-motion connection in said accelerator control, and de-control means connected to said accelerator control for rendering said vacuum responsive means inoperable coincident with initial movement of said lost-motion connection, whereby the vacuum control device is redered inoperative'upon actuation of the accelerator control before regulation of the carburettor thereby.

2. In an internal combustion engine having a carburettor and an intake manifold, a control device entirely vacuum-operated free of the speed of said engine for reducing the vacuum on the carburettor during periods of engine-braking or vehicle over-running; said control device comprising a main chamber, apartition dividing said chamber into upperv and lower sections and having an opening therein providing communication between the two such sections, said lower section being fitted between the carburettor and the'intake manifold of the engine, said upper section having an inlet for atmospheric air, a vacuum break valve normally closing the opening of said partition, a movable vacuum responsive member operatively connected to said vacuum break valve and normally occupying a position with the valve closed, said movable member being mounted in a housing defining on oneside of the member a vacuum chamber subjected to vacuum in the carburettor to draw the member into the vacuum chamber and thereby cause the valve to move to open position, at least one air inlet to such vacuum chamber provided with control means for opening and closing the same, opening of such inlet venting the vacuum chamber to the atmosphere to render said movable member inoper- 5 able and closure thereof sealing the vacuum chamber so that the member may be operated as aforesaid to control the valve in response to the vacuum within the carburettor, an accelerator control for said carburettor, said accelerator control including a lost-motion connection, and 5 means operatively connecting the accelerator control to the controlmeans in the air inlet to said vvacuum chamber for opening such inlet coincident with the initial movement of such lost-motion connection, whereby the" vacuum chamber is vented to the .atmospherebefore the 10 accelerator operates the carburettor. 1

References Cited in the file of this patent UNITED STATES PATENTS Loew Apr. 7, 1931 Vander Veer Mar. 31, 1936 Rodman May 3, 1938- Stone July 11, 1944 Hieger Feb. 11, 1947 i Mallory May 20, 1947 'Flint Nov.- 9, 1948 Reeves Sept. 18, 1956

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