US3060916A

US3060916A - Valve control mechanism for internal combustion piston engines

Info

Publication number: US3060916A
Application number: US57446A
Authority: US
Inventors: Buchi Alfred Johann
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-09-26
Filing date: 1960-09-21
Publication date: 1962-10-30
Anticipated expiration: 1979-10-30

Description

Oct. 30, 1962 A. J. BUCHI 3,060,916

VALVE CONTROL MECHANISM FOR INTERNAL COMBUSTION PISTON ENGINES Filed Sept. 21, 1960 2 Sheets-Sheet l Oct. 30, 1962 A. J. BUCHI 3,060,916

VALVE CONTROL MECHANISM FOR INTERNAL COMBUSTION PISTON ENGINES Filed Sept. 21, 1960 2 Sheets-Sheet 2 United States Patent D 3,060,916 VALVE CONTROL MECHANISM FOR INTERNAL COMBUSTION PISTON ENGINES Alfred Johann Buchi, Archstrasse 2, Winterthur, Switzerland Filed Sept. 21, 1960, Ser. No. 57,446

Claims priority, application Switzerland Sept. 26, 1959 7 Claims. (Cl. 123-79) The present invention relates to valve control mechanism for internal combustion piston engines of the kind having concentric inner and outer valves, the outer valve being guided in the cylinder head and the inner valve being guided within the outer valve.

According to the invention there is provided valve control mechanism for an engine of the kind described comprising an overhead camshaft, rocker arms operable by cams on said cam shaft for opening the valves, spring means for closing the valves, a cam on the camshaft and a rocker arm for the inner valve being arranged in a plane containing the valve axis, and two cams on the camshaft and two rocker arms for the outer valve being spaced symmetrically of the valve axis and extending parallel to the cam and rocker arm for the inner valve, said rocker arms being rotatably mounted on a common shaft, an element intermediate the rocker arms and the outer valve and operatively connected to the actuating stern of the outer valve, said element comprising a cup- -like centre part and extensions parallel to the cam shaft and projecting from the cup-like centre part, said extensions co-acting with the rocker arms of the outer valve to open the outer valve, and said cup-like centre part co-acting with said spring means for the outer valve, and a retainer member for the spring means of the inner valve, said retainer member having at least two arms and being firmly connected to the actuating stem of the inner valve, the arms on the retainer member being received in slots in said cup-like centre-part, the arms being reciprocable in said slots.

Specific embodiments of the invention are shown by way of example in the accompanying drawings whereof:

FIG. 1 is an axial section transversely through the cylinder head of an internal combustion engine having valve control mechanism according to the present invention, the control mechanism being shown in its position in which the inner valve is open,

\FIG. 1a corresponds with FIG. 1 but shows the valve control mechanism in its position in which both the valves are closed.

FIG. 2 is a longitudinal section through a part of the cylinder head and the control mechanism shown in FIG. 1.

FIG. 3 is a transverse section showing a modification of part of the control mechanism shown in FIGS. 1, la and 2.

FIG. 4 is a longitudinal section corresponding with FIG. 3.

FIG. 5 is a plan view of a part of the control mechanism shown in FIGS. 3 and 4.

FIG. 6 is a longitudinal section showing a further modification of part of the control mechanism shown in FIGS. 1, 1a and 2 and,

FIG. 7 is a plan View of FIG. 6.

In FIGS. 1, 1a and 2, Z is the cylinder head and R is a housing for the cylinder head and the control gear. The outer valve V is guided in the cylinder head and V is the inner valve moving concentrically of and inside the outer valve. The valves are opened by an overhead cam shaft '1 with control cams 2 and 3 (FIG. 2) and by means of rocker arms 4 pressing on the valve stems or valve spring retainers. The valves are closed again by the

valve springs

6 and 6a for the inner valve and valve 3,066,916 Patented Oct. 30, 1962 springs 9 for the outer valve. FIG. 1 shows the inner valve V in the open position and the outer valve V in the closed position. In FIG. 1a, both valves are closed, the inner valve bearing on the outer valve and the outer valve on the cylinder head. Each of the two valves has its control members which can be actuated independently of those appertaining to the other valve. The cam shaft 1 is driven in known manner through a transmission from the crankshaft. The middle cam lies in a transverse plane of the cylinder head, which plane extends through the centre line of the valves, the middle cam controlling the inner valve V The other two cams control outer valve V and are also provided in a transverse plane of the cylinder head which is parallel to the cylinder axis. The control cams press on the rocker arms 4 and these can be provided with a device 5 which cancels outlhe play between one rocker arm and the pressure points on the valve rods. The rocker arms 4 are rotatably fixed on the shaft 4b and are so designed that they are interchangeable. The restoring means of the inner valve consist of two two-part hair-

pin springs

6 and 6a, which act each via a stirrup 7 on the one end of a two-armed

valve spring retainer

8, 8a which may be constructed in the form of a yoke and rigidly attached to the stem 13 by means of a two part conical member 16. The

spring retainer

8, 8a has at 8b a track of a width to accommodate horizontal movement of the stirrup 7.

The

springs

6 and 6a are held at the other end on the cylinder head by means of a plate 20. The return spring of the outer valve V consists of a helical spring 9, as shown in FIGS. 1, la and 2. Between the rocker arms 4 for the outer valve and the actuating stem 15 there is disposed a pot-shaped engine element 10, which comprises a centre part 10 and extensions 10a projecting from the upper rim of the centre part (FIG. 2). The extensions ltla each co-operate with one rocker arm 4 and in known manner with movable ball sockets 10c and ball pins 411. The base of this engine element is screwed fast to the hollow stem 15 of the outer valve V The screw connection 15a consists of an internal thread of one attachment 11 projecting outwardly from the base of the engine element, and an external thread on the hollow stem 15. The attachment 11 is made in one piece with the pot-shaped engine element or is connected rigidly to the latter. The screw connection 15a is locked by means of a screw-threaded nut 12. The engine element serves the purpose of a retainer for the spring 9 of the outer valve, it being supported on the cylinder head Z and pressing on the base portion of the element 10 for closing the outer valve V FIGS. 3 and 4 show a modification of the pot-shaped engine element. In this case, the engine element 16' comprises two separate upper and lower parts 18 and 14 whereof the downward projection of the lower part 14 is attached to the actuating stem 15 of the outer valve. A ball joint 19 is provided between the upper cup or potlike part 18 and the lower part 14, and the pot 18 is supported in a spherical surfiace 14a of the lower part 14, which is screwed fast to the hollow stem 15 or is made in one piece with the stem. The base of the pot 18 is given a suitable spherical form for forming the ball joint 19. With this modification, the outer valve with the stem 15 and the lower part 14 can be rotated about the stem 13 of the inner valve.

FIG. 5 is a plan view showing the relative positions of the members serving as spring retainers for the outer and inner valves, and of the yoke 8 and the pot-shaped element 10' in the construction according to FIGS. 3 and 4. The yoke arms 8a of the inner valve and the vane-like extensions we of the pot-shaped element 18 are set at right-angles to one another. Furthermore, the yoke arms 8a extend into the wall of the element 10' through slots b displaced by 180. Owing to the ball joint .19, the sockets 100! can be'made in one piece with the arms 10c or be connected fast thereto. In the event of any inaccuracies in the setting of the rocker arms a satisfactory guiding of the stem in the guideway 21 without any binding is assured because of the ball joint. The formation of the operative point between the rocker arm and engine element in the form of a ball joint 4a/10d, in conjunction with the ball joint 19, provides for axial power transmission of the control forces transmitted -from the control cams to the valves.

In FIGS. 6 and 7, a helical spring 6 is provided instead of the two-part hair-

pin springs

6, 6a with stirrups 7, which spring 6' surrounds the helical spring 9 and the pot 18 of the element 10' for the outer valve V The valve spring retainer 8' for the cylindrical spring 6 is three-armed with arms 8a offset at 120 relatively to one another. These arms co-operate with the cylindrical spring 6 by means of a ring 6". As described for the two-armed spring retainer in connection with FIG. 4, the three-armed spring retainer 8' is connected fast to the stem 13' of the inner valve by means of keys 16. The pot 18 of the element 10' can be of the same design as that of the element 10 in FIGS. 3 to 5. However, a suitable formation of the

slots

10b and 10b" is provided for guiding the three armed spring retainer.

What I claim is:

1. A valve control mechanism for internal combustion piston engines of the type having a cylinder head, concentric inner and outer valves, means guiding the outer valve in the cylinder head, means guiding the inner valve in the outer valve, a common lever shaft, levers mounted on said shaft for operating each of a pair of said inner and outer valves, an intermediate element, said intermediate element being defined by a body having a base portion secured to the other valve and an upper portion provided with an open end, extensions projectin from the open end of the upper portion transversely with respect to the levers, a return spring for the outer valve with one end of the spring bearing against the base portion of the body and the other end against the cylinder head, a retainer means secured to the inner valve, at least two arms on said retainer means, the upper portion of the body having slots for receiving said arms to allow reciproca'ble movement of the arms, a return spring for the inner valve with one end of the inner valve return spring coacting with said arms and the other end coacting with said cylinder head, means operably connecting one of the levers with said inner valve for actuating the inner valve, and means operably connecting each of said extensions with a lever for actuating the outer valve through said intermediate element.

2. The control mechanism as claimed in claim 1, including an actuating stem for the outer valve, means firmly securing the base portion of the intermediate element to the actuating stem, and a rotatable joint means between the base portion and the upper portion thereby allowing the actuating stem and base portion to rotate relative to the inner valve.

3. The control mechanism as claimed in claim 2, in which said joint means is defined by spherical surfaces on the base portion and upper portion.

4. The control mechanism as claimed in claim 1, including an actuating stem for the outer valve, and means firmly securing the base portion of the intermediate element to the actuating stem.

5. The control mechanism as claimed in claim 1, in which the return spring for the inner valve is of hair-pin form and the return spring for the outer valve is of helical form centered on the valve axis.

6. The control mechanism as claimed in claim 1, in which the return springs for the inner and outer valves are of helical form centered on the respective valve axes.

7. A valve control mechanism for internal combustion piston engines of the type having a cylinder head, concentric inner and outer valves, means guiding the outer valve in the cylinder head, means guiding the inner valve in the outer valve, a common lever shaft, levers mounted on said shaft for operating each of a pair of said inner and outer valves, a hollow actuating stem for the outer valve, an actuating stem for the inner valve mounted within the actuating stem for the outer valve, an intermediate element for each pair of inner and outer valves,

said intermediate element including a lower part and an upper part having an open upper end, means securing the lower part to the actuating stem for the outer valve, spherical surfaces on the upper part and the lower part constituting a rotatable joint between such parts, extensions projecting horizontally from the open end of the upper part transversely with respect to the levers, a retainer means fastly secured to the actuating stem for the H inner valve, said retainer means having three arms offset 120 relative to one another, said upper part having three vertical slots offset 120 relative to one another for receiving said arms with the free ends of the arms extending outwardly of said upper part, a ring carried by the free ends of said arms, a helical return spring surrounding the actuating stem for the outer valve with one end of the spring bearing against the lower part and the other end bearing against the cylinder head, a helical return spring for the inner valve surrounding the return spring for the outer valve with one end of the return i spring for the inner valve bearing against said ring and the other end bearing against said cylinder head, means operably connecting one of the levers with the actuating stern of the inner valve for actuating the inner valve, and means operably connecting each of said extensions with a lever for actuating the stem of the outer valve through said intermediate element.

References Cited in the file of this patent UNITED STATES PATENTS 1,589,441 Stenger June 22, 1956 FOREIGN PATENTS 406,424 France Dec. 8, 1909 179,406 Great Britain May 11, 1922 416,496. Great Britain Sept. 17, 1934