US2190738A - Antistall device - Google Patents

Description

Feb. 20, 1940. J, SCHWEISS 4 2,190,738

ANTISTALL DEVICE Filed Sept. 19, 1938 Egg@ y .fm/enfoca d-Ose/o c/we/SS Patented Feb. 20, 1940 UNITED STATES PATENT OFFICE AN'rIs'r-ALL DEVICE Application September 19, 1938, Serial No. 230,716

3 Claims.

'I'his invention relates to carburetors for in-v ternal combustion engines and consists particularly in a novel antistalling device therefor.

Devices have been suggested which utilize 5 intake manifoldy suction to slightly open the carburetor throttle valve whenever the suction in the engine intake system drops excessively. These devices hold the throttle valve open when there is no suction in the intake system, or in i l other words, when the engine is inoperative and thus cannot be'used in carburetors having antipercolating mechanism, as described, lfor instance, in Moseley Patent No. 2,013,787. 'I'his `mechanism requires full closing of the throttle l valve when the engine is inoperative in order to open a vent for relieving vapor pressure formed at the base of the main nozzle and prevent the gasoline from spilling into the intake manifold.

It is an object of the present invention to provide an antistall device which may be utilized with a carburetor embodying antipercolating.

mechanism as described in the Moseley patent.

Another object is to provide an antistall device which is constructed and arranged to insure slight opening of the throttle valve when the suction in the engine intake system drops sui'- ciently to indicate that the engine will stall if the throttle valve is permitted to fully close, but which permits full closing of the throttle valve at all other times.

These objects and other more detailed objects hereafter appearing are attained substantially by the structures illustrated in the accompanying drawing in which:

Fig. 1 is a side view of a portion of an internal combustion engine intake system including the carburetor and apart of the intakefmanifold, with the invention applied thereto.

Fig. 2 is a detail section taken substantially on line 2-2 of Fig. 3.

Fig. 3 is a detail side view and section taken substantially on line 3-3 of Fig. 1.

Fig. 4 is a side view and section illustrating a modification.

Fig. 5 is an enlarged diagrammatic view illus,- trating a part of the structure in Fig. 4.

Fig. 6 is a view showing a part of the structure inFig. 2, but in a different position.

Fig. 1 illustrates a downdraft carburetor in- 50 cluding a barrel portion I, flanged-at its lower end as at 2 and attached by means of bolts 3 to the intake manifold 4, the usual "hot spot 5 being provided. The usual constant level chamber 6 is located adjacent barrel I. Pivotally 5| mounted on shaft 1 near the lower portion of barrel I, is a butterfly-type throttle valve 8. Shaft 1 projects beyond both sides of the barrel and at one'end carries an arm 9 for connection to the usual accelerating pump (not shown) by means of a link 9a and lever 9b. A lever I0 rigid 5 with the other end of shaft 1 has two pairs of Voutstanding threaded lugs II and I2 mounting stop screws I3 and I4. Lever I0 is perforated at one end as at I5, for attachment to the usual manual control mechanism connected to the ac- 10 celerator pedal.

A bracket I 6 is mounted between the carburetor flange and manifold and at its outer end carries a suction device generally indicated at I1. Device |1 includes a diaphragm I8 normally urged 15 to the right byl a coiled spring I9 (see Fig. 4). A tube 20 connects the device with the intake manifold suction. A guide tube 2l extends horizontally from the suction device and slidably receives a rod 22 secured to the vdiaphragm and 20 having at its outer extremity annular ridges 23, 24 and 25 with recesses 26 and 21 therebetween. A small hole or recess 28 in the upper wall of tube 2I near the outer end thereof receives a loose ball plunger 29 whch is in position to be 25 engaged by screw I4 on lever IU.

In operation, suction device I1 is constructed to insure the maintenance of diaphragm I8 in its left hand or inward position whenever normal operative suction exists in the intake manifold, 3o

this including the lowest suction which prevails when the throttle valve is substantially closed and with the engine continuing in operation. Spring I9 is calibrated to move diaphragm I8 and rod 22 to the right only when the intake suc- 35 tion approaches zero so as to indicate that the engine is about to stall unless the throttle valve is opened. In s uch case middle ridge 24 on rod 22 is moved under ball 29, as shown in Fig. 6, raising the same into the path of screw I4 so as 40 to prevent full closing of the throttle valve or to open the valve slightly if it is already closed. When the speed of the engine again picks up, diaphragm' I8 is drawn to the left permitting ball 29 to drop into recess 21. When the engine stops 45 operating and there is no suction in the intake system, spring |19 forces rod 22 fully to the right permitting ball 29 to drop into recess 26, as in Fig. 2. This permits full closing of the throttle valve and, consequently, opening of the antipercolator vent, as described in the above mentioned Moseley patent. Screw I4 is adjusted so as to just clear ball 29 when the latter is in either of the recesses 26 or 21. Screw I3 cooperates with a stop 30 on the outside of barrel I to limit 55 the closing movement of the throttle valve to. its normal idling position.

In Figs. 4 and 5 is shown a modiiication utilizing a suction device l1 as in the previous form. A lever 35 is pivoted at 36 to carburetor barrel I and a bell. crank lever 31 is pivotally connected to the lower extremity thereof, as at 38. Lever 31 has a curved slot 39 in the lower portion theref of slidably receiving apin 40 projecting from lever Ilia on throttle shaft 1. Diaphragm actuated rod 22 is pinned to the end of lever 31 opposite slot 39.

Whenever normal operating suction exists in ment of the toggle levers movesthe upper edge of slot 39 slightly downwardly so as to: engage pin 4.0 and prevent full closing of the throttle valve, or open the valve. When there is no suction in the intake system, toggle levers 3.5 and 31v will be moved to a disaligned position opposite the solid line position in Fig. 5, again permitting full closing of the throttle valve.

Fig. 5 indicates diagrammatically the three positions of toggle levers 35 and 31 which permit free opening movement of the throttle valve at l drops to a point to indicate that the engine is all times and also permit full closing of the valve except when the suction in the intake system about to stall.

The novel antistall device may be used with substantially any type of carburetor. and, although', an important advantage of the device is obtained when it is used with an anti-percolating device as disclosed in the above-mentioned Moseley patent, the device has other advantages and may be used where no anti-percolator is provided. The specic form of suction responsive device shown is not essential. The structure shown may be modied in the above and other respects as will occur to those skilled in the art However, in case the intake suction drops conduit, aguide projecting from said device havand the exclusive use of all such modications as come within the scope of the appended claims is contemplated.

I claim:

l. In combination with internal combustion en- 5 gine intake conduit'including a carburetor having a throttle valve and on operating arm therefor,'a device responsive to suction in said conduit, a lever pivoted adjacent said mechanism, a second lever pivotally connected to said rst lever and having a slot, said arm having an element movable in said slot and said levers forming a toggle. and a rod operated by said device and connected to one of said levers intermediate Ithe ends of the toggle so as to disalign said levers when there is normal operatinggsuction and when there is no suction in said mechanism and to substantially valign said levers when the intake pressure apw proaches atmospheric, said throttle arm element being freely movable in said slot to permit full opening andclosing of said throttle valve when said levers are disaligned but cooperating with an end of said sloty when said levers are aligned to insure at least partial openingof said throttle valve.

2. AIn combination with an internal combustion engine intake conduit including a carburetor having a throttle valve and operating mechanism therefor, a device responsive to suction in said ing a recess adjacent said mechanism, a plunger in said recess, and a rod connected to said device and vmovable thereby along said guide, 'said rod having a raised portion for engaging said plunger when the intake pressure approaches atmospheric `to move the same into the path of said mechanismto insure at least partial opening of said throttle valve and said rod having recessed structure adjacent said raised portion to permit full closing of'said throttle when the intake suction fails.

3. The combination of elements specified in claim 2 in which said recessed structure is constructed and arranged to permit full closing of said throttle valve Vwhen normal operating suc- 4 tions exist in said intake conduit.v

JOSEPH SCHWEISS.

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