US2289116A - Valve-actuating mechanism for internal combustion engines - Google Patents

Description

VALVE-ACTUATING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed Sept. 29, 1941 5 Sheets-Sheet 'l A B 8/ L llllll llllll! IIIHIHIIIIHU mum . mnwvrm I R3 5 r M F B.HAL FQRI ATTORNEYS y 1942. F. B. ALFQRD r 2,289,115

VALVE-ACTUATING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed Sept. 29, 1941 s Sheets-Sheet 2 B K IIIIR II E K E g .2 2 J1; E I 2; E F g X J x //vl/NTOR F. 814 ALFoRb y 1942- F. B. HALFORD 2,289,116

VALVE-ACTUATING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed Sept. 29, 1941 3 Sheets-Sheet 3 Patented July 7, 1942 VALVE-ACTUATING MECHANISM FOR INTERNAL CONEBUSTION ENGINES Frank Bernard Halford, Edgware, England, as-

signor to D. Napier & Son Limited, London, England, a company of Great Britain Application September 29, 1941, Serial No. 412,901 In Great Britain September 5, 1940 3 Claims.

This invention relates to valve-actuating mechanism for internal combustion engines of the type comprising banks of cylinders arranged in U or H form and has for its object to simplify the construction and arrangement of this mechanism especially where the valves of the engine are sleeve valves of the type to which reciprocating and oscillating movement is imparted.

An engine of the U type has two banks of cylinders arranged in parallel planes and operating on parallel crankshafts, the cylinder arrangement having in end view a U form. In an engine of the H type there are four banks of cylinders arranged in pairs and opposed so that they resemble two engines of U type arranged oppositely. The cylinders in such an H type of engine lie in two parallel planes and act on two crankshafts spaced apart side by side.

Valve-actuating mechanism for engines of the above-mentioned type according to this invention comprises in combination a shaft which is supported in bearings spaced apart along it and lies between two banks of cylinders, the shaft extending longitudinally and parallel with the crankshafts on which these cylinders act and from one of which crankshafts this shaft is driven through gearing, a series of shafts arranged adjacent and transversely with respect to the said longitudinal shaft along which these transverse shafts are spaced apart, gearing through which each transverse shaft is separately driven from the longitudinal shaft, and means whereby each transverse shaft as it is rotated imparts movement to the valves of two cylinders situated in separate banks and on opposite sides of the longitudinal shaft.

In the preferred construction there is a series of worms spaced apart along the longitudinal shaft and with the bearings which support the shaft between them. On eachof the transverse shafts is a worm wheel which engages one of the worms on the longitudinal shaft. Cranks at the ends of each of these transverse shafts engage and impart reciprocating and oscillatory movement to the sleeve valves of twocylinders situated in separate banks and on opposite sides of the longitudinal shaft.

In such an arrangement of valve-actuating mechanism lubricant under pressure for the several transverse crankshafts and the bearings in the cranks thereof is supplied through each of these crankshafts by way of passages leading thereto from adjacent fixed parts in which are the bearings for the longitudinal shaft. Each transverse crankshaft is formed hollowed to contain the lubricant which passes thence to bearings in the cranks at the opposite ends of this shaft, the lubricant on its way to the interior of that crankshaft being delivered to at least one annular groove in a fixed part in which are the bearings of this crankshaft and with which communicate one or more radial passages in the wall of that crankshaft. Alternatively the annular groove may be in the rotating part and passages registering with that groove may be formed in the fixed part. Again, there may be an annular groove in each part, these grooves being positioned so that they will register and permit the oil to flow from one to the other.

This improved arrangement simplifies the assembly of an engine either of the U or H type. It enables two banks of cylinders to be assembled with their valves and the improved valveactuating mechanism comprising the worm-carrying shaft between the cylinder banks. The whole can then be mounted on the crank case, the pistons which have been already connected to the engine crankshaft being then inserted in the respective cylinders. The two cylinder blocks, whether these are formed separate or integral, can then be bolted up to the crank case. The arrangement is particularly convenient where an engine of the H type is constructed and arranged, more particularly with respect to the firing of the charges in the cylinders, as described in the specification of the present applicants United States of America Letters Patent No. 2,214,529.

The accompanying drawings illustrate a construction that may be adopted in carrying out the invention. In these drawings,

Figure l is a somewhat diagrammatic plan showing a part of a transmission shaft with the mechanism for actuating therefrom the sleeve valves of cylinders in two separate banks.

Figure 2 is a somewhat diagrammatic plan showing the general lay-out of the shafting and gearing through which the actuation of the valves is effected.

Figure 3 is a diagrammatic end view of the shafting and gearing shown in Figure 2 as seen from the left hand side of that figure. This figure also indicates the arrangement of the banks of cylinders in an engine of the H type.

Figure 4 is a longitudinal sectional elevation of one of the crankshafts by which the sleeve valves are actuated and showing one arrangement for conveying lubricant to the parts.

Figure 5 is a view similar to Figure 4 but showing an alternative arrangement of the passages for lubricant.

Figure 6 is again a similar view but showing another arrangement of the lubricant passages.

Referring to Figures 1, 2 and 3, the longitudinal worm-carrying shaft is here shown as driven through suitable gearing from the one engine crankshaft. The shaft A has on it and suitably spaced apart along it the worms B. Bearings C for this shaft are arranged in pairs on either side of the worms, the shaft being carried by these bearings in a suitably formed bracket or other member or part D of which portions are seen in Figures 4, and 6.

In Figure 3 is indicated the arrangement in an engine of H type wherein there are four banks of cylinders indicated at E E E E The two banks of cylinders E, E act on the one crankshaft F while the two banks of cylinders E E act on the second crankshaft G. These two crankshafts are geared together through gear wheels F G on the respective shafts and an intermediate gear Wheel H. On the one end of the worm-carrying shaft A is a gear wheel A which meshes with a wheel J on one end of an intermediate shaft J on the other end of which is a gear wheel J This meshes with a gear wheel K on an intermediate shaft K and this wheel in turn meshes with the gear wheel F on the crankshaft F. A second longitudinal wormcarrying shaft A similar to the shaft A is driven through similar gearing from the wheel F on the crankshaft F. The arrangement is indicated both in Figure 2 and in Figure 3, the intermediate gear wheels through which the drive is transmitted from the crankshaft F to the worm shaft A being indicated at K J and J. A gear wheel similar to the gear wheel A through which the worm-carrying shaft A is driven need not necessarily be placed at the end of that shaft, as in the arrangement illustrated, but may be situated if preferred at some intermediate point in the length of that shaft.

Mounted in bearings in the bracket or similar part D and adjacent to each Worm B is a short crankshaft L which extends transversely with respect to the shaft A and carries thereon, preferably about the centre of its length, a worm wheel M which meshes with an adjacent worm B on the shaft A. Each of the cranks L which are on the end of the shaft L engage through a spherical or like hearing a pin N projecting laterally from a sleeve valve N to which as the crankshaft L is rotated is given a reciprocating and oscillating movement in a known manner. As will be seen in Figure l, by this means this movement is imparted simultaneously by the one crankshaft L to two sleeve valves in cylinders situated oppositely and in separate banks of cylinders. Thus. for example, two of the sleeve valves seen in Figure 1 as being reciprocated by a single crankshaft L may be in cylinders in the two banks of cylinders E and E in the diagrammatic view in Figure 3.

Lubricant is delivered under pressure to the transverse crankshafts L and to the bearings in the cranks L on the ends thereof through passages arranged in various ways in the fixed parts or brackets D and in each crank or in the parts carried thereby. Figures 4, 5 and 6 illustrate alternative arrangements for such delivery of the lubricant.

In each case the crankshaft is formed hollow, and referring first to the arrangement shown in Figure 4, this shaft L has internally an annular space L which surrounds and is formed by a tube 0 which extends through the crankshaft the tube being fixed to the latter at its ends, as for instance by spinning or similarly enlarging the ends in the manner shown in Figure 4, thus closing in the annular space L From this space lead passages L to the bearings in the cranks L The worm Wheel M is conveniently formed on an annulus M which engages and is suitably connected to a radially projecting flange L formed about the centre of the length of the crankshaft L. In the bracket member D are the bearings P for the crankshaft L and in the part of this bracket member which lies between one of the bearings P and the flange L is an annular groove R which faces a cylindrical part L of the crankshaft L. Through this part of the crankshaft one or more oil passages L lead in a radial direction, the ends of these passages register with the groove and thus establish communication between the space L within the crankshaft and the annular groove R. Lubricant passes to the annular groove R through passages indicated at R R in the bracket or hearing member D. These passages may lead from one of the adfacent bearings C in which is carried the shaft A and through these passages the lubricant can be delivered under pressure to the annular groove R whence it can pass to the bearings P, to the space L within the crankshaft L and to the bearings in the cranks L Turning to the alternative arrangement for delivering lubricant to the crankshaft as shown in Figure 5, in this case the interior L of each crankshaft L is cylindrical but with its opposite ends closed as by discs L sprung into place, or fixed in some other convenient manner. The whole of the interior of the crankshaft thus constitutes a receptacle for lubricant which can pass thence through passages L to the bearings in the cranks L As in the construction shown in Figure 4 the worm wheel M is formed on an annulus M mounted on a radial flange L situated about the centre of the length of the crankshaft L between the roller bearings P In a part where the worm wheel annulus M and the crankshaft flange L abut there is formed in the crankshaft flange an annular groove L with which communicate one or more radial passages L leading to the interior L of the crankshaft. Passages S lead through the worm wheel annulus M each of these passages registering at one end with the annular groove L and the other end of each passage terminating in an opening in an annular groove S in the side face of the worm wheel. As will be seen there is an annular groove S in each side face of the worm wheel annulus M and the passages S alternate in opening into these annular grooves. In each adjacent face of the bracket member D is an annular groove R between which and the groove S in that side face of the worm annulus M is placed a flat metal ring T through which are a series of holes T which will register with the annular grooves S and R These rings T fioat, each being prevented from radial movement as it lies in a slight recess in the face of the bracket member D. From each annular groove R passages R lead to some point whence lubricant can be delivered into these passages under pressure. As in the arrangement described above this lubricant may flow to these parts from the bearings on the shaft A. The floating metal rings T serve to take the thrust.

Referring to the construction shown in Figure 6, this is similar in general arrangement to that shown in Figure 4, but differs in certain details. Here again the interior of the crankshaft L is cylindrical with the ends closed by discs L Into this interior L passages L run from a cylindrical external part L of the crankshaft. Opposite to the radial passages L is an annular groove R to which lubricant is delivered under pressure through one or more passages R in the bracket or bearing part D. In this case the crankshaft L is carried in ball bearings P in place of the roller bearings P or P shown in Figures 4 and 5. In Figure 6 is indicated one of the bolts by means of which the worm wheel annulus M is attached to the radial flange L on the crankshaft.

In place of the actuation of the valves N from the shaft A being effected by a series of worms on the shaft and a series of worm wheels on the transverse crankshafts as described above, in some cases it may be desirable to employ skew gear wheels on these parts through which valveactuating crankshafts such as L are driven from the longitudinal driving shaft A.

In the case of the construction of transverse crankshaft L as above described with reference to Figure 4 the thrust may be taken by providing taper roller bearings P for that crankshaft. In the case of the construction shown in Figure 5 and as mentioned above, the floating rings T serve to take up thrust, ordinary roller bearings P then being employed. This provision to take up thrust is desirable where the transmission is by way of worms on the longitudinal shaft A and worm wheels on the transverse shafts L. It is still more necessary to take up thrust where skew gearing is employed as above indicated.

If the engine is of U form and thus has only two banks of cylinders arranged as E and E in Figure 3, only a single longitudinal shaft A is required to transmit movement to the valves of all the cylinders in these two banks.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a mechanism for actuating the sleeve valves of an internal combustion engine, the combination of a driving shaft, a series of worm gears on said shaft spaced apart with bearings for the shaft between these gears, means for supplying lubricant under pressure to each of these shaft bearings, a series of hollow shafts lying adjacent and transversely with respect to the said driving shaft, a worm gear on each transverse shaft engaging a corresponding worm gear on the driving shaft, cranks at the ends of each of the said transverse shafts which engage and impart reciprocating and oscillatory movement to the sleeve valves of two cylinders, said parts having passages through which lubricant can pass from the said bearings of the driving shaft into the adjacent hollow crank shafts and to the bearings thereof and through the wall of each crank shaft whereby lubricant can pass from within the crankshaft to the crank pins on the ends thereof.

2. In a mechanism for actuating the sleeve valves of an internal combustion engine, the combination of a driving shaft, a series of worm gears spaced apart along the shaft, fixed parts in each of which is a bearing for the driving shaft located between the gears on the said shaft, means for supplying lubricant under pressure to each of these shaft bearings, a series of hollow shafts carried in bearings in the said fixed parts and lying adjacent and transversely with respect to the driving shaft, a worm gear on each transverse shaft engaging a corresponding worm gear on the driving shaft, cranks at the ends of each of the said transverse shafts which engage and impart reciprocating and oscillatory movement to the sleeve valves of two cylinders, said parts having passages through which lubricant can pass from the said bearings of the driving shaft through the said fixed parts into the hollow crankshafts and to the bearings thereof, and also through the wall of each crank shaft from within the crank shaft to the crank pins on the ends thereof.

3. In a mechanism for actuating the sleeve valves of an internal combustion engine, the combination of a driving shaft, a series of worm gears spaced apart along said shaft, fixed parts in each of which is a bearing for the driving shaft, said bearings being located between the gears on the said shaft, means for supplying lubricant under pressure to each of these shaft bearings, a series of hollow shafts carried in bearings in the said fixed parts and lying adjacent and transversely with respect to the driving shaft, a worm gear on each transverse shaft positioned about the center of the length of that shaft and between the bearings of the shaft, a corresponding worm gear on the driving shaft coacting with the first worm gear, cranks at the ends of each of the said transverse shafts which engage and impart reciprocating and oscillatory movement to the sleeve valves of two cylinders, each of said fixed parts having at least one passage through which lubricant can pass from the said bearings of the driving shaft, the wall of the adjacent crank shaft having at least one passage adapted to register with the end of said first lubricant passage whereby as said crankshaft rotates the lubricant can pass into the hollow within the crankshaft, the wall of each crankshaft having passages through which lubricant can pass from within the crankshaft to the crank pins on the ends thereof.

FRANK BERNARD HALFORD.

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