US1490613A - Valve mechanism - Google Patents

Description

April 15 1924. 1,490,613

A. LE-PORT ET AL VALVE MECHANISM Filed Feb. 25. 1922 2 Sheets-sheer 1 April 15 ,1924. 1,490,613

A. LEF'ORT ET AL VALVE MECHANISM Filed Feb. 23. 1922 2 Sheets-Sheet 2 ilatented Apr. l5, Y 1." 'v q" l l il hi il STATES PATENT OFFCE.

VALVE ianonemsm.

Application filed February 23, 1.922. Serial No. 538,752.

To all whom t may concern j Be it known that we7 ARMAND Lnron'r and NELSON D. JENKINS, citizens of the United States, andy residing in the city and county of Sanlirancisco, State of California, have invented a new andu'seul improvement in a Valve Mechanism, oiwhich the ollowing is a specification. Y

Uur invention relates to improvements in valve mechanisms for internal combustion motors wherein the exhaust valves of a pair of cylinders are operated by a single tappet and push rod, and the intake valves of the same pair of cylinders are Similarly operated by a single push rod and tappet, said tappets operating in conjunction with cams mounted. directly on the crank shaft by ymeans of which cams said intake and exsynchrowherein the actuating cams are mounted directly upon the crank shaft of the motor thereby reducing lost motion and providing as more correct and closer timing adjustment between the valves and the crank shaft.

A still further object of the invention is to provide a new and improved valve mechvanism wherein a single tappet and push rod is arranged to actuate two valves. either exhaust or intake therebyfurther reducing ythe number of parts.

We ac'complishthese and other objects by means 4ci the preferred form of the invention disclosed in the drawings forming a part ot the present specification, wherein like numerals of references are used to designate similar parts throughout the said specification and drawings, andin which:

Fig. 1 is a vertical sectional view of a four-cylinder internal combustion -motor, disclosing lour invention applied thereto;

ldig. 2vis-a plan view of the'motordisclosing the arrangement of the upper portions of the valve actuating mechanism;

Fig. 3 is a vertical sectional view taken on line 3-k-3 Aoi? Fig. 1 of the drawings; and

Fig. 4 is an enlarged plan view oft the actuating cams.

Referring to the drawings the numerall vis used to designatein general an internal Ved the usual pistons 6,7, Sand 9 respectively, said cylinders being connected in the usual manner by means of suitable connecting rods 11 to a crank shaft 12 rotatably mounted in what we term split bearings 14. yEach cylinder is provided with an intake valve 1G actuated by rocker arms 17, and an exhaust valve 18 similarly operated by rocker arms 19.

ln order to more clearly illustrate the manner in which the intake and exhaust valves of a pair of cylinders is actuated and operated in synchronism with the cycles of the pistons of thatpair of cylinders we will describe the valve mechanism for the centralypair of-cylinders 3 and 4.

For convenience thepush rod ends of all o1 the rocker arms 17 and 19 arearranged in the same vertical plane with the crank shaft 12. y

A vertically disposed/push rod 21 is rotatably mounted in the motor 1 in its central plane and is provided at its upper end with a semi-circular plate 22 which plate, when the push rod 21 is rotated in a man ner hereinafter more fully described, alte-rnately moves under the adjusting screws 23 mounted in the push rod ends of the rocker arms 19 of the exhaust Valves 18 of the cylinders 3 and 4.

The lower end of the push rod 21 is de.

the same relative position to each other when connected,

yThe tappet 24 is provided adjacent its lower end with two pair of diametrically disposed arms 26 and 27 arranged at right angles to each other and in diierent planes, as disclosed in Figs. 1 and 3 of the drawings.

A double-faced cam 28 is mounted directly upon thecrank shaft 12 midway of the split bearing 14 and is provided on one side with an inclined projection 29 which extends approximately one-quarter distance around the face of said cam and is arranged to engage one of the diametrically opposed arms 26 and move the same and the tappet 24 through a one-quarter revolution when one of the arms 27 will then be brought within the path of a second projection 31 which is inclined for a quarter distance on the face of the cam 28 and which engages said arm 27 and again moves the tappet 24 through another quarter revolution, the

Vremaining portion of the projection 31 being parallel with the plane of rotation so as to engage the side of the arm 27 and hold the same against further movement as disclosed in Fig. 4 of the drawings.

In other words, during one-half of each revolution of the cam 28 the push rods will be rotated through one-half of a revolution which will move the semi-circular disc 22 from an engageable position below one exhaust valve rocker arm 19 of the cylinder 3 to the engageable position below the push rod end of the rocker arm of the exhaust valve 18 of the cylinder 2, or vice versa. In other Words rotation of the push rod 21 Will move the semi-circular member 22 thereon to be moved alternately into engageable positions beneath the rocker arms of a pair of two adjacent cylinders.

A second push rod 32 is rotatably arranged parallel with the push rod 21 and is likewise provided with a semi-circular'plate 33 which is arranged to be moved alternately into engageable positions between the rocker arms 17 of the intake valves 16 of the cylinders 2 and 3.

It is obvious then, that one push rod will be operated to engage and actuate two exhaust valves while the second rod for that pair of cylinders will similarly be operated to engage and actuate the two intake valves of the same pair of cylinders.

The projections 29 and 31 are the same on all of the cams 28 excepting that said projections are positioned to actuate their respective exhaust and intake valves in synchronism with the cycles of their respective cylinders.

Directly mounted upon the crank shaft 12 and on each side of the cam 28 is a tappet cam 34 which engages the bottom of its respective tappet and raises said tappet and push rod to move the semi-circular portion on top of said push rod to engage the adjusting screws 23 on the rocker arms and through said rocker arms to actuate their respective valves. These cams 34 are also timed or positioned relatively to each other and to the crank shaft to actuate said tappets, push rods and rocker arms in synchronism with the cycles of the pistons.

As there is only one cylinder on each end of the motor and two push rods must be provided for actuating the intake and exhaust valves properly we have provided a bifurcated dummy rocker arm 36 adjacent these push rods, which bifurcations assume the same relative position to the rocker arms of the adjacent cylinder which would be assumed by the rocker arms of another cylinder,

Laconia These dummy rocker arms are provided to take the push of the rods and cams 34 when the valves of the end cylinder are not to be operated, as during the 'compression and firing strokes.

In operation we will assume that cylinders 2, 3, 4 and 5 are, according to the standard order of lil-ing, on their intake, compression, exhaust and firing strokes, respectively, as indicated in Fig. 1 of the drawings by the letters I, C, E and F.

The pistons 7 and 8 of the cylinders 3 and 4 respectively, being illustrated at the ends of their compression and exhaust strokes respectively, it is obvious that the exhaust valve 18 of the cylinder 4 has Vjust been closed by the action of the tappet 24'and the projections 29 and 31 on the cam 28, these projections being then in the position disclosed in Fig. 3 of the drawings. It is also obvious that the intake valve 16 of the cylinder 4 is about to be opened and this is illustrated by the dotted position of the cam 34 immediately to the left of the central bearing cam- 28, which is turning over toward the observer and is about to lift the tappet 46 and push rod 32 to actuate the rocker arm 17 of the intake valve 16 of said cylinder 4.

Reference to Fig. 2 of the drawings will disclose that both semi-circular plates 22 and 33 are positioned under the ends of the rocker arms 17 and 19 of the cylinder 4.

During the next half revolution of the` crank shaft the tappet 24 will be rotated to Abring the plate 22 under the exhaust valve rocker arm 19 of the cylinder 3 and the same half revolution of the crank shaft will cause the cam 34' on the left hand side of the central bearing to raise the tappet 46, plate 33 and actuate the rocker arm 17 to operate the intake valve 16 of the cylinder 4 as that cylinder will then be on its intake stroke.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

1. The combination with an internal combustion motor, crank shaft, valves and pistons thereof, of a tappet arrangedto actuate the exhaust valves of a pair of adjacent cylinders of said motors; a second tappet arranged to actuate the intake valves of the same cylinders; and cams mounted directly upon said crank shaft and arranged to actuate said tappets to alternately engage and actuate the intake and exhaust valves of said cylinders in synchronism with the cycles of said pistons.

2. Thecombination with an internal combustion motor, crank shaft, valves and pistons thereof, of a tappet arranged toV alternately engage and actuatethe exhaust valves of adjacent cylinders of said motor; a second tappet arranged to alternately engage and actuate the intake valves of the same cylinders; means for actuating the said tappets to alternately engage their respective valves; and means directly mounted upon the crank shaft for actuating said tappets in synchronism with the cycles of the said cylinders.

3. The combination with an internal cornbustion motor, crank shaft, valves and pistons thereof, of a tappet for each pair of cylinders arranged to be moved into engageable position With either one of the intake valves of said pair of cylinders; a second tappet arranged to be moved into engageable position With the exhaust valves of said cylinders; and means directly connected to the crank shaft of said motor and arranged to actuate said tappets to engage said valves and actuate the said valves in synchronism with the cycles of its respective piston.

4. The combination With an internal combustion motor, and the crank shaft, valves and pistons thereof, of a rotatable tappet mountedvvithin said motor for each pair of cylinders, when rotated intermittently, to be moved into engageable position With either intake valve of said pair of cylinders; a second tappet rotatably mounted and arranged to be moved into engageable position with either exhaust valve of said pair of cylinders; means directly mounted upon the crank shaft for rotating the tappets to move the same into engageable position to the Sja proper valve; and means mounted directly on the said crank shaft for actuating said tappets to operate their respective valves in synchronism with their respective pistons.

5. The combination With an internal combustion motor and the crank shaft, valvesv rotatably mounted Within said motor for the same pair of cylinders and likewise having a semicircular plate on the top thereof arranged to be moved into engageable position with either exhaust valve of the same pair of cylinders; a cam mounted directly on the crank shaft and arranged to engage the lower ends of both tappets and to rotate the same to bring the semi-circular plates into engageable position with the proper valves and in synchronism with the pistons; and cams mounted on either side of the first mentioned cams and arranged to actuate the tappets to operate the valves in synchronism With said pair of pistons.

In Witness whereof We hereunto set our signatures.

ARMAND LEPORT. NELSON D. JENKINS.

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