US1490305A - Valve for two-cycle internal-combustion engines - Google Patents

Description

April 15 1924. 1,490,305

E. F. ANDREWS ET AL VALVE FOR TWO-CYCLE INTERNAL COMBUSTION ENGINES Original Filed April '7, 1919 srar PAT

GREECE.

EDWARD r. AnnREwsor CHICAGO, Ann RAY E; ACRE, or WHEA'TON, ILLINOIS.

VALVE FOR Two-CYCLE INTERNAL-COMBUSTION enemas.

Application filed. April 7, 1919, Serial No. 288,070. Renewed September 22, 1923.

To all whom it may concern:

Be it known that we, EDWARD F. AN- .nnnws, a citizen of the United States residing at Chicago, in the count of Cook and State of Illinois, and RAY ACRE, a

citizen of the United States, residing at Vheaton, county of Du Page, State of Illinois, have invented certain. new and useful Improvements in Valves for Two-Cycle Internal-Combustion Engines, of which the following is a specification.

This invention relates to improvements in valves for internal combustion engines of the two-cycle type.

One object of the invention resides in the provision, in a two-cycle internal combustion engine, of'an intake valve of the rotary cylindrical type, whereby wear and leakage may be reduced to a minimum, thus avoiding the chief objections to the use of disc valves of the type now so commonly employed.

Another object of the invention is to provide means for driving the said cylindrical valve at crank shaft speed directly from the crank pin thereby dispensing with gears and other complicated valve operating mechanisms.

A further object of the invention resides in the provision .of a valve of the type described which may be utilized in operating the timing mechanism of the ignition system of the engine or for driving a magneto or other device for supplying ignition to the. engine.

Another obiect of the invention is to provide, in combination with a valve of the type described, means whereby the ignition timing mechanism or a magneto or similar device may be driven directly from said valve.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying is illustrated.

Figure 1 is a vertical sectional view taken through a portion of the crank case of a two-cycle engine showing a valve constructed in accordance with the present invention mounted in operative position, and v Fig. 2 is a sectional "iew taken on the line 2--2 of Fig. 1, and Fig. 3 is a detail view showing the timing devices of the iging open at its inner end in order to drawings wherein one form of the invention I longitudinal nition system operatively associated with the actuating shaft carried by the valve.

Referring more in detail to the drawings, a lower corner of the crank case of a twocycle internal combustion engine is shown 'in section in Fig. 1, the bottom of the crank case being designatedas 10 and the rear .wall thereof, which is preferably removable,

the axis of the crank shaft 11, is shown the j intake valve 13-of the engine,wh1ch according to the present invention is of the rotary, hollow. cylindrical type, said valve bevide an outlet orifice 14 leading 1nto the crank case or compression chamber. The

inner end of the rotary valve 13 adjacent the outlet orifice 14: thereof is preferably provided with a suitable outwardly-flared flange 15 designed to seat against the adjacent wall of the crank case to thereby re-' tain the valve against lon itudinal dis-. placement outwardly. Depending from this flange 15 is a driving arm 16 for the rotary valve, afsuitable pin 17 being provided at the lower end of this arm 16, said pin be.- ing received within asuitable bearin 18 which is mounted within a hole 19 provided in the crank pin 11", said hole 19 and the bearing 18 lining the same, being arranged concentrically in said crank pin. By the arrangement of parts just described, it will be noted that upon rotation of the crank shaft the rotary valve 13 will be driven at crank shaft speed'directly from the crank pin and further thatksaidvalve will be maintained properly disposed and against displacement inwardly by means of the engagement of the lower end of the driving arm 16 against the outer surface of the bearing 18.

The rotary valve 13 is provided with a suitable slot 20 which is designed to register with the fuel passage 21. provided in the adjacent wall of the crank case, at the proper time and for the proper duration with relation to the ,cycleof operation'of the engine to properly admit thefuel charge into the interior of the crankcase or compression chamber. The fuel passage 21 communicates with the carburetter or other charge formingdevice at its lower end. It

I will be understood, however, that the valve brings into registration the slot and passage 21 and then cuts off such registration,

,thus effecting the opening and closing of said valve. Int-he conventional two-cycle engine, the slot 20 and passage 21 remain in registration for approximately 180 of. each revolution, while the piston is ascending in the cylinder and remain out of registration for the remaining 180 of each revolution, while the piston is descending, compressing the charge in the crank case preparatory to its being-bi-passed into the cylin- 'der upon the opening of the transfer ports.

The valve 13, by reason of its mounting within, the rear wall of the crank case, its relation thereto and the manner in which the same is driven, namely at crank shaft speed, directly fromthe crank pin, renders it very convenient and advantageous to utilize said valve as a means for operating either the timing mechanism ofthe ignition systemof the engine or a magneto or similar device for supplying ignition to the engine. With the above in view, the rear end of the rotary valve 13 is provided, in the present form of the invention, with a stub shaft 22, which shaft is fixed to the valve casing so as to revolve therewith and preferably projects outwardly therefrom through the adjacent wall of the crank case in such wise that its outer end is exposed exteriorly of said case, as shown clearly in Fig. 1. This outer'exposed, end of the shaft 22 is preferably provided with a cam surface 23 by means of which said shaft may be readily utilized for operating any desired form of timing mechanism for the ignition system,

' such for instance as shown in Fig. 3 of the drawings, in order to supply a properly, timed spark to the cylinder of the engine. The cam surface, when thus utilizing the shaft 22, acts to operate the make and break contact 35 of said timing mechanism. It will be readily observed. however,- that, if desired, the exposed portion of the shaft 22 may be coupled in any suitable manner,

either by utilizing the cam surface 23, or

otherwise, directly with a magneto of any standard type, or other like device, for the purpose of driving the same by means of powertransmitted thereto directly through the rotary valve for supplying ignition to the engine. The timing mechanism shown in Fig. 3 of the drawings is of special construction and formsthe subject matter of a. separate application, the same being included herein merely to illustrate generally the manner in which the valve and associated part 22 thereof are utilized in operating such mechanism. It will be apparent to those skilled in the art that any form of timing mechanism may be employed.

It will be noted that during the operation of the engine oil will be supplied to the bear ing surface of the valve 13 in the same manner that the other parts of the engine within the crank case thereof are lubricated. A portion of the oil thus supplied to the valve may, during the continued operation thereof, pass throughout the length of said valve and be deposited in the space 24 intermediate the outer end thereof and the adjacentwall of the crank case. To guard against the oil, which may so pass rearwardly into this .chamber 24, leaking therefrom outwardly through the rear wall of the crank case, a small duct" 25 is provided, which forms a communication between said chamber 211 and the fuel passage 21. From this it will be noted that any oil, which may pass into the chamber 24, will be immediately drawn back into the crank case during the succeeding. suction stroke of the engine by reason of the duct 25 and its communication with the fuel passage just described.

At 26 is illustrated a centrifugally actuated governor for the valve 13. This governor forms the subject matter of a separate apphcation and accordingly no claim is herein laid to the same. Briefly, it comprises a gate valve 26 pivoted at 26 to an arm 27 which projects outwardly from the periphvery of the flange 15 of the valve 13. The valve 26" is held normally in the position shown in Fig. 2 of the drawings by means of a suitable spring 28, the tension of which may be controlled by any suitable adjusting means, such as the screw 29 which engages through an upstanding lug 30 provided on the end of the arm 27. The valve 26 on the other side of the pivot 26 is provided with a governor arm 26 slotted as at 26 and provided with a suitable weighted element 26, said weight being adjustable within the slot 26 longitudinally of the arm 26. Fromthe above it will be noted that when the cylindrical valve 13 is rotated, carrying with it the weighted governor, the centrifugal force will act upon the weight 26 in such wise as to swing the gate valve 26 on its pivot 26", thus effecting a partial closing of the rotary valve outlet orifice 14. By proper adjustment of the spring 28 and the weight 26 such partial closing of the outlet orifice 14 of the valve can be made proportional to the rotational speed, thus providing a very effective, simple andeconomical governor for the -engine.

From the above it will bevnoted that a valve for two-cycleinternal combustion engines has been provided, the wear on which will be evenly distributed over its entire Itwillbe-further observedfrom'the fore- 4 going that, by reason of the valve and its construction and arrangement relatively to the crank shaft and casing, the same may be driven, as for example, by the novel means herein described and illustrated directly from the crank pin at crank shaft speed thereby eliminating the use of compli-v cated and troublesome driving mechanisms magneto orjsimilar-device. This is an ad-' vantage of peculiar'slgnificance 1n engines ofthe particular type shown in the drawings, wherein an overhung crank shaft is employed, and this, for the reason thatonly one end of such crank shafts'are exposed, such exposed end being necessarily constructed in order that the same may be employed: for the attachment of a starting crank. Thus it will be observed that, if the ignition apparatus is also placed on the end of the shaft, the construction is thereby complicated and the most satisfactory arrangement of parts cannot, therefore, be obtained. Attention is also directed to the feature of construction embodied in'the present improvements whereby any fuel or oil, which may leak past the cylindrical valve, is

quickly returned to the crank case of the engine, thus preventing waste or leakage.

It will be obvious to those skilled in the art that various changes and modifications crank case and ignition system, of a rotary cylindrical valve in one wall of said crank case, means for actuating said valve from said crank shaft, and a stub shaft carried by said valve and extending exteriorly of said crank case for operating said ignition system.

3. The combination in an internal combustion engine having a crank case and ignition system, ofan intake valve mounted in one wall of said crank case, means for operating said valve, and means associated with said valve for operating said ignition system.

4. In a two-cycle'internal combustion en gine, a crank case, a crank shaft, a fuel passage, a hollow, rotary, cylindrical valve open at its inner end into said case, said valve being mounted in one wall of said case adjacent the end of said shaft, and provided with a port adapted to register intermittently with said passage to admit fuel through saidvalve into said case, and means interposed between said valve and the end of said shaft for driving the former at the speed of the latter. 7

5a In an internal combustion engine, a crank case, a crank shaft terminating at one end in said case, a rotary cylindrical valve mounted in one wall of said case adjacent the end of said shaft and in line therewith, and means interposed between the adjacent ends ofsaid valve and shaft for operating the former at the same speed as the latter.

6. In an internal combustion engine, a crank case, a crank shaft terminating at one end in said case, a rotary cylindrical valve molmted in one wall of said case adjacent the end of said shaft and in line therewith, means interposed betweenthe adjacent ends of said valve and shaft for operating the former at the same speed as the latter, and means associated with said valve at the other end thereof for actuating the ignition system of the engine.

7. In a two-cycle internal combustion engine, a crank shaft, a rotary cylindrical "alve and an ignition system actuator, all of said elements being mounted on a common axis, and means for operating said valve and actuator from said shaft and at the same speed that said shaft is operated.

8. In a two-cycle internal combustion engine, a crank case, a crank shaft, a fuel passage, a hollow, rotary, cylindrical valve open at its inner end into said case, said valve being mounted in one wall of said case adjacent the end of said shaft, andpro vided with a port adapted to register intermittently with said passage to admit fuel through said valve into said case, and an operating arm depending from the inner end of said valve wlthln sa d case and provided with means for engagement with the crank pin of said shaft whereby upon operation of said shaft, said valve will be revolved at the speed of said shaft.

- shaft, and means for exposing fuel or oil which may leak past said'valve to the influence of the suction produced in said case whereby such fuel and oil may be drawn back into said case with the fuel charge thereby preventing leakage and waste thereof.

11. The combination in an internal combustion engine having a crank shaft, crank pin and crank case, of a rotary intake valve journalled in an opening provided in one wall of said crank case in line with the axis of said shaft and having a radial arm connected with said crank pin.

12. In an internal combustion engine, a crank case, a crank shaft having a crank pin, a fuel passage, a rotary valve operatively associated therewith for admitting fuel into said crank case during properly timed intervals in the cycle of operation of said engine, a crank arm' carried by said valve within said crank case, and a crank pin carried by said arm and engaging the the latter and the crank pin of said crank shaft, whereby said Valve will be operated at the speed of said shaft upon rotation thereof.

13. In a two-cycle internal combustion engine, an ignition system therefor, a crank shaft, a crank case, a rotary cylindrical valve in one wall of said crank case, means for actuating said valve from said crank shaft, a stub shaft carried by said valve and extending exteriorly of said crank case for operating said ignition system, and a cover plate fitted within the wall of said crank case around said shaft and formin together with the end wall of said va ve a 14. In a two -cycle internal combustion engine, a crank shaft, a crank case, a'fuel passage, a rotary cylindrical valve in one chamber for the collection of fuel and oil which may leak -past said valve.

wall of said crank case operatively associated with said passage, means for actuat-' ing said valve from said crank shaft, a

chamber adjacent the outer end of said valve for the collection of fuel and oil which may leak past. the latter, and a duct providing acommunication between said chamber and said fuel passage, whereby oil collecting in said chamber will be returned-to the crank case of said engine upon each suction stroke thereof.

In testimony whereof, we have subscribed our names.

EDWARD F. ANDREWS RAY E. ACRE.

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