US1170087A - Valve-operating mechanism for internal-combustion engines. - Google Patents

Description

O. E. MICHAUD.

VALVE OPERATINGMECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JAN. 9, 1915.

Patented Feb. 1, 1916.

ONESIME E. MICHAUD, OF ST. LOUIS, MISSOURI.

VALVE-OPERATING MECI-IANISM FOR. INTERNAL-COMBUSTION ENGINES.

Speccation of Letters P atent.

Patented Feb. 1,1916.

`App1ication filed January 9, 1915. Serial No. 1, 275.

To all whom it may concern Be it known that I, ONESIME E. MICHAUD, a citizen of the United States, and a resident'of the city of St. Louis and State of Missouri, have invented a new and useful Improvement in Valve-Operating Mechanism for Internal-Combustion Engines, of which the following is a specification.

My invention relates to' valve Operating mechanisms, particularly to valve Operating mechanisms for internal combustion engines. 4

The principal object of my invention is a valve Operating mechanism which positively opens and closes the valves, and which will he rapid and reliable in its operation.

Further objects will appear more ully liereinafter.

Generally stated, the invention consists in a valve Operating mechanism'in which the Yalve is opened and also closed positively by the direct action of a tappet mechanism operatively connected to' the crank shaft of the engine.

The invention further consists in the parts and in the arranp'ements and combinations of part-s more fully set' forth hereinafter.

In the accompanving drawinos which form part of this specification, and in which like reference characters refer to like parts throughout the se eral views"Figure 1 is a vertical cross-section throuh one cylinder of an upright internal combustion' engine. showing a valve Operating' mechanism emhodving the invention applied thereto. the valve heinr in its 'closed position: Fiq. 2 is a fragmentary cross-section similar to Fig. 1 showing the parts ot the va'lve O erating mechanisn in their positions when the v'alve is open: and Fie 3 is a fra'gmentarv section through the lower portion of'th'e valVe operating rod and actuating mechanism, 'showing how the parts o erate incase the direction ot' rotation of the engine is reversed.

Referring to the accompanying drawings, a valve Operating mechanism emhodying the invention is shown applied to an internal combustion engine of ordinarv'construction. The engine comprises a'cylin'der 1 and a crankcase 2 Secured to, said cylinder. Mounted in the crank-case 2 is a crank-shaft 3 which is connected by means of a crankarm 4 and a connecting rod 5 to a piston 6 Operating in the cylinder 1. Mounted in the crank-case 2 at 'one'side of the crank- 'shaft 3 and parallel to it is a" shaft 7 which has a sprocket wheel 8 Secured thereto. Secured to the cranloshaft 3 is a second sprocket-wheel 9' which hashalf as many teeth as the sprocket-wheel 8, and connecting said sprocket-wheels is a sprocket chain 10. Also mounted in the crank-case 2, di-

rectly above the shaft 7 and parallel to it, is a second shaft- 11. The lower shaft 7 and the upper shaft 11 have intermeshing gears 12 and 13 respectively seeured thereto. The

gears 12 and 13 are of the same size and u serve to connect the shafts 7 and ll so that they rotate in opposite directions. The lower shaft 7 has Secured thereto a sleeve 14 which has an integral projection 15 constituting a valve opening cam or tappet.

Secured to the upper shaft 11 is a second sleeve 16 which'has an integral projection 17 constituting a valve closing cam or tapina screw-threaded portion; Interposed between the sleeve 20 and the valve casing. is

a compression coil spring 21 which operates to hold the valve D its closed position.

cr collar 20 having a downwardly proecti i' Slidablv mounted in the crank-case 2 is a val e Operating rod 22 which has a longitudinal hore or recess 23 extendin do nwardlv therein frmnits upner end. The upper portion of this bore is larger than the lower end` formin@ an axial recess which is screw-threaded at the top and is ada ted 'to recei e the'screw-threaded ortion of the sleeve 20 which is seoured to the valve stem 18. Extendine* through thelower end of the-here into the recess 23 is a plunger 24:,

which has integral therewith at its lower -end a cireular'head 25, larger than the rod 22. Mourted in the recess 23 surrounding the stem of the plune'er s a compression COll tom of said recess, and the other end of which 'enqaees a'washer 27. The ,Washer 27 is heldin place on the plunger 2 by a pin 28. A circumferential rib or collar 29 surrounds the rod22 a short distance above' its lower end.

In assembling the parts associated with the rod 22, the stem of the plunger 24; s pushed upwardlv through the bore into the spring 26 one end of whichengagesthe bot- ;reess 23 said rod th e spring ;2 6 and the Washer 27 are inserted through the upper end of the bore into the recess and assembled on the stem, and the pin 28 is inserted in its place in the stem through a hole 80 in the rod 22. The sleeve 20 is then screwed into the upper end of the recess 23 to connect the rod 22 and the valve stem 18.

The operation of the valve Operating mechanism is as follows: The tappet 15 engages the under face of the head 25 and, as said head is normallv held bythe spring 26 against the lower end of the rod 22, the rotation of the shaft 7 in the direction of the arrow (Figs. 1 and 2) raises the rod 22 and opens the valve. The outer surface of the tappet 15 is curved in the arc of a circle having the center of the shaft 7 as its center, and this curved surface engages the head 25 and holds the valve open during the upstroke of the pisten 6. At the end of the up stroke of the piston, the tappet 17 engages the unper face of the collar 29 to push the rod 22 downwardlv and close the valve. The parts are so proportioned and connected that the valve is alternatelv opened and closed at the proper times corresponding to the position of the piston in the cylinder of the engine. v

It freouentlv hanpens that an engine recoils and rotates the crank shaft for Dart of a revolution in the direction oppos te to the direction of its normal rotation. When this reverse movement of the crank-shaft occurs` the lower shaft 7 will be rotated in a counter-clnckwise direction. as shown b v the arrow in Fig. 3. Such rotation of the shaft 7 will cause the tannet 15 to engage the head 25 and move it down` thereby tendin& to move the valve beyond its closed position. In o der to rel e e the downward Dressure on the valve which would o herwise result in an iniurv or breaking ofsome of the parts` the head 25 and the plunsxer 24: are sebarable from he rod 22, and thev mav mo e downwardlv relative to the rod 22 against the tension of the serine' 26.

The val e Operat ng' mechanism shown and hereinbefore described onera es to open and also to close the valvepos tivelv. Acco d ng l as the movements ofthe valve are not dependent unon t e .action of the spring, i

thev can be made wi h recision as rapidly as is desirable: and thus the valve mechanism can be timed more accu atelv than heretofore to attain a greater eiicieney and an increased sneed of the engine The snrinq 21 which normallv ho ds the valve closed. can be weaker than in the ease where the closinr of the val e depends on this snring alone. thus avoiding evere shocks to ;the v-alve when it closes. 'of the valve Operating shafts 7 and 11 at 'one side of the valve Operating rod 22 enables the rod 22 to be actuated bfv a direct push .of the tappets '115 ;and 17 as these 'tap- The arrangement pets move upwardly and' downwardly re- Spectively. By this Construction the sliding friction incident to the use of cam surfaces is largely avoided.

I do not wish to be restricted to the particular Construction and arrangement of parts shown and hereinbefore described.

What I claim is:

1. A valve Operating mechanism for internal combustion engines' comprising a valve, a rod for Operating said valve, said rod having members constituting shoulders, and tappets mounted adjacent to said rod and rotating in opposite directions said tappets being arranged to engage said members of said rod alternately to open and close said valve. I

2. A valve Operating mechanism for internal combustion engines comprising a valve., a rod for Operating said Valve, said rod having members constituting shoulders, two shafts arranged one above the other at one side of said rod, and a sleeve Secured to each shaft and having a projection capable of engaging one of said members of said rod, said shafts being rotated in opposite directions.

3. A valve Operating mechanism for internal combustion engines comprising a Valve, a rod for Operating said valve, said rod having' spaced members connected thereto which constitute shoulders, two shafts mounted adjacent to said rod and ;rea-red together to rotate in opposite directions, and a cam Secured to each shaft and intermittently engaging one of the shoulders of said rod.

45. A valve Operating mechanism for internal combustion engines comprising a valve, a rod for Operating said valve, said rod having a collar fixed thereto, a member movablv'mounted on said rod. the movement of said member being limited in one direction, and tappet's mounted adiacent to said rod and operated in onposite directions, said tappets engaging said collar and said member alternately to open and close said valve.

5. A valve onerating mechanism for internal combustion engines' comprising a valve a rod' for Operating said valve, said rod having' a collar integral therewith, a plunger slidablv mounted in said rod and having a head larger than said rod. said head of said plunger normallv engag ng the end of said rod, a spring holding said plunger in 'its normal position, and tappets mounted adiacent to said rod and operated in ooposite directions, said tappets engaging said collar and said head alternately to open and close said valve.

6. A valve Operating mechanism for .internal combustion engines comprising a valve, a rod for Operating said valve. said rod having' a colla-r integral -therewith, a plunger 'slidably mounted ;in said rod and having a head larger than said rod, said head normallv engaging the end of said rod, a spring for holding said plunger in its normal position, two shafts mounted one above the other at one side of said rod and geared together to rotate in opposite directions, a sleeve Secured to one shaft and having a projection thereon arranged to engage said collar, and a sleeve Secured to the other shaft and having a projection thereon arranged to engage the head of said plunger, said sleeves engaging said collar and said head alternately to open and close said valve.

7. A valve Operating mechanism for internal combustion engines comprising a Valve, a rod for Operating said Valve, a member operatively connected to said rod and movable relatively thereto, means for limiting the movement of said member relatively to said rod in one direction, and a tappet mechanism operatively connected to the crank-shaft of said engine and arranged to engage said member during the normal direction of rotation of said crank-shaft in said direction in Which the movement of said member relatively to said rod is limited, said tappet mechanism upon reversal of direction of rotation of said crank-shaft of the engine engaging and moving said member relatively to said rod Without moving said valve.

Signed at St. Louis, Missouri this 7 th day of January, 1915.

ONESIME E. MICHAUD. VVtnesses:

NEIL D. PRESTON, MARTHA A. SHELTON.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C."

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