Driving Gear for the Valve Motion of Motor Engines.
Year: 1887

page_text: Date of Application, 21st Mar., 1887.
Complete Left, 20th July, 1887.
Complete Accepted, 23rd Aug., 1887.
Driving Gear for the Valve Motion of Motor Engines.
1 CHARLES DENTON ABEL of 28 Southampton Buildings Chancery Lane in the
County of Middlesex, Consulting Engineer and Patent Agent do hereby declare the
nature of this invention to be as follows:-
This invention relates to improved means for driving the valve gear of motor
engines from the engine shaft, and it is applicable in all cases where the valve motion
is not worked directly from the engine shaft but from a separate way shaft. The
object of the invention is to actuate the way shaft or valve gear shaft in such a manner
that it receives precisely the same motion as the engine shaft, while at the same time
the reversal of the eccentrics upon the way shaft or valve gear shaft is effected by a
simple shifting of the driving gear. This is effected by driving the way shaft by
means of an endless pitch chain or articulated chain or a band, the chain or band
being tightened by means of stretching rollers, by shifting which the way shaft
receives a partial rotation relatively to the engine shaft, whereby the desired shifting
or reversal of the valve gear is effected. The shifting of the stretching rollers is
effected in such a manner that they are simultaneously moved between two end
positions so that the chain or band always remains stretched, while either the
following part is lengthened just as much as the leading part is shortened, or, vice
versa, the relative rotation of the way shaft being effected by such shortening of the
one side and lengthening of the other side.
When an endless band or belt is employed, this has either holes formed in it at
equal distances along its length or notches along its edges, which gear with teeth or
studs on the peripheries of the driving and driven pullies.
The arrangements of parts for carrying out the above described invention may
be carried out in a variety of ways, both with horizontal vertical, and inclined
engines. Thus according to one arrangement, suitable for vertical engines, the endless
band or chain passes from the engine shaft pulley to the way shaft pulley over two
CD077

page_text: stretching pullies situated respectively on the leading and on the following side of the
band, being both within the same and in such positions, that the band passes at an angle
over one or both of them. The stretching pullies are carried by pivotted arms that
are connected together by a link, so that if the arm of the one pulley be moved so as
to shift its pulley, the other arm and pulley will be simultaneously shifted to the same
extent in the same direction.
By such movement the one side of the endless band will be drawn outwards to an
increased angle, and the other part will move inwards to a less angle, and by thus
shortening the one part of the band and lengthening the other part the before
described relative partial rotation will be imparted to the way shaft so as to effect
the reversal or shifting of the valve gear, the reversal being effected when the way
shaft is turned through an angle equal 2 (90°-8) where & is equal to the lead angle
of the eccentric.
According to another arrangement the endless band is bent into two loops lying in
the same direction in passing from the engine shaft to the way shaft and the two
stretching pullies being situated respectively in one of the loops, so that the one
pulley is within the endless band and the other outside of it. The axes of the
rollers are carried by slides actuated by a right and left handed screw or by other
suitable mechanism, whereby they can be shifted simultaneously nearer to or farther
away from each other to an equal extent.
By such motion of the pulleys the one loop will be lengthened and the other
shortened, and the relative partial rotation of the way shaft will thus be effected as
before.
T
1 1000

page_text: COMPLETE SPECIFICATION.
Driving Gear for the Valve Motion of Motor Engines.
I, CHALES DENTON ABEL of No. 28 Southampton Buildings Chancery Lane in the
County of Middlesex, Consulting Engineer and Patent Agent do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
This invention relates to improved means for driving the valve gear of motor
engines from the engine shaft, and it is applicable in all cases where the valve motion
is not worked directly from the engine shaft but from a separate way shaft. The
object of the invention is to actuate the way shaft or valve gear shaft in such a manner
that it receives precisely the same motion as the engine shaft, while at the same
time the reversal of the eccentrics upon the way shaft or valve gear shaft is effected
by a simple shifting of the driving gear. This is effected by driving the way
shaft by means of an endless pitch chain or articulated chain or
the chain or band being tightened by means of stretching rollers, by shifting which
a band,
the way shaft receives a partial rotation relatively to the engine shaft whereby the
usual shifting or reversal of the valve gear is effected. The shifting of the stretching
rollers is effected in such a manner that they are simultaneously moved between two
end positions, so that the chain or band always remains stretched, while either the
following part is lengthened just as much as the leading part is shortened or, vice
versa, the relative rotation of the way shaft being effected by such shortening of the
one side and lengthening of the other side.
When an endless band or belt is employed, this has either holes formed in
it at equal distances along its length or notched along its edges, which gear with
teeth or studs on the peripheries of the driving and driven pullies.
The arrangements of parts for carrying out the above described invention may be
constructed in a variety of ways, both with horizontal, vertical, and inclined engines.
Thus according to one arrangement, suitable for vertical engines, the endless band or
chain passes from the engine shaft pulley to the way shaft pulley over two stretching
pullies situated respectively on the leading and on the following side of the band
being both within the same and in such positions that the band passes at an angle
over one or both of them. The stretching pullies are carried by pivotted arms that
are connected together by a link, so that if the arm of the one pulley be moved so as
to shift its pulley, the other arm and pulley will be simultaneously shifted to the same
oxtent in the same direction.
By such movement the one side of the endless band will be drawn outwards to an
increased angle, and the other part will move inwards to a less angle and by thus
shortening the one part of the band and lengthening the other part, the before described
relative partial rotation will be imparted to the way shaft so as to effect the reversal
or shifting of the valve gear, the reversal being effected when the way shaft is
turned through an angle equal 2 (90°-8) where is equal to the lead angle of the
eccentric.

page_text: According to another arrangement the endless band is bent into two loops lying in
the same direction in passing from the engine shaft to the way shaft, the two stretching
pullies being situated respectively in one of the loops, so that the one pulley is within
the endless band and the other outside of it. The axes of the rollers are carried by
slides actuated by a right and left handed screw or by other suitable mechanism
whereby they can be shifted simultaneously nearer to or farther away from each other
to an equal extent.
By such motion of the pullies the one loop will be lengthened and the other shortened,
and the relative partial rotation of the way shaft will thus be effected as before.
On the accompanying drawings are shewn two arrangements of the above described
invention for vertical marine engines, Fig. 1 and 3 shewing the two general arrange-
ments of the engine to a small scale, while Fig. 2 shows a diagram of the gear for the
arrangement at Fig. 1 and Fig. 4 a diagram of the gear shewn in Fig. 3. In the
arrangement shewn at Figs. 1 and 2, the engine shaft I is geared with the way
shaft V by means of a pitch-chain or band led over guide pullies II II that keep it
stretched. The guide pullies are mounted on pins on levers IV IV which are
connected together by a rod III. If now the one lever IV be turned upon its centre
or y the same motion will be imparted to the other lever and consequently both guide
pullies 11 II will be moved from their position a a into the positions bb, thus shifting
the chain into the finely dotted position. By this notion the one side of the chain
or band will have been shortened while the other will have been lengthened to the
same extent, and consequently the countershaft V will have been turned relatively to
the mainshaft to the required extent for effecting the reversal of the valve gear,
namely through an angle equal to 2 (90°-8) where & represents the angle of lead of
the eccentric. In the arrangement at Figs. 3 and 4 the two guide rollers II II arc
arranged, the one inside and the outside the endless chain or band, instead of both
inside as in the previous arrangement and they are carried in blocks that are directly
shifted in contrary directions by a right and left handed screw, so that, for reversing,
the guide pullies are shifted from the positions a a to the positions bb, thus effecting
the turning of the way shaft V as before described.
The keeping the endless chain or band stretched by the pullies II II may obviously
be effected by other means than by levers or screws as described, such as by weights
or by fluid pressure acting on a piston.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed I declare that what I claim is :-
1. Actuating the valve gear of motor engines from a way-shaft driven from the
engine shaft by an endless chain or band so arranged that by simultaneously altering
the positions of its leading and following sides it effects the reversal of the valve gear,
substantially as herein described.
2. In motor engines whose valve gear is actuated from a way shaft driven from the
engine shaft by an endless chain or band, the use in combination with the endless
chain or band of two guide pullies over which the same is led and which are so
arranged that by shifting them simultaneously the way shaft is partly rotated relatively
to the engine shaft substantially as herein described.
1007