Improvements in or relating to the Valve Mechanism of Explosion Engines.
Year: 1896

page_text: a
Date of Application, 30th Dec., 1898
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Valve Mechanism of Explosion
Engines.
I, JOHANNES VAN TOLL, Engineer, of 13 Heathfield South, Twickenham, in the
county of Middlesex, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the valve mechanism of explosion engines, and by it
I am able to dispense with the gearing usually employed for the purpose of reduc-
ing the number of operations of the valve mechanism below that of the revolutions
of the engine shaft. The invention may be applied to any or all of the valves
as required, say for example the exhaust valve.
In carrying out the invention I employ an eccentric block which rotates with
the engine shaft and in the periphery of this I form grooves or a divided groove
so arranged that at one portion of the periphery there is only a single groove,
and at the other portion there are two, the dividing strip of metal preferably
terminating at a point at one or both ends, the eccentric block thus arranged,
operating as a cami as well as an eccentric.
The valve may be of any suitable type-the mushroom type preferred-and
controlled by a spring or other means so that it normally remains in its closed
position or vice versa according to the arrangement. Between the valve and the
eccentric is arranged a tubular or other rod or equivalent which in certain positions
will engage with the stem of the valve and under the operation of the eccentric
operate it, while in certain other positions due to the cam portion of the eccentric
this rod is moved clear of the valve stem and so does not operate the valve. The
rod may be carried in a pivotted sleeve so as to allow of the rod travelling inwards
in the sleeve, and having its axial plane varied by the turning of the sleeve about
its pivot. Other means may however be employed to carry this rod. The opera-
tion is as follows:-
One end of the rod engages permanently with the groove in the eccentric and
it may be retained there by a spring, a strip or gravity; this end is preferably,
forked so as to obtain a suitable bearing and hold upon the block. The operation
of the eccentric as it rotates causes this rod to travel axially to and fro while the
operation of the cam groove at certain times causes the other end of the rod to
engage with the valve, and at other times to clear it thus obtaining the results
usually secured by means of toothed gearing.
I do not bind myself to employ a groove in the eccentric block so long as the
result I have described is attained. As an example of a variation, the side faces
of the block could be suitably shaped and the rod forked to correspond, and thus
obtain the same result; or a raised face could be formed upon the periphery of
the eccentric.
For the purpose of operating or controlling this mechanism by or from the
governor, I may make the eccentric loose upon the shaft and by means of feathers
cause it to rotate therewith, but leave it free to travel longitudinally thereon,

page_text: the governor by means of a suitable jaw and grooved collar upon the eccentric or
by other suitable means causing it to travel upon the shaft. By thus moving
the eccentric the rod can be controlled so that no matter what its position in regard
to the cam it does not engage that the valve and therefore does not operate it.
The eccentric may be similarly operated by hand if desired.
.
.
1000
BOULT & WADE
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to the Valve Mechanism of Explosion
Engines.
"I, JOHANNES VAN TOLL, Engineer, formerly of 13 Heathfield South, Twickenliam,
Middlesex, now of 18 Radford Street, Coventry in the county of Warwick, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and' by 'the following
statement:-
This invention relates to the valve niechanism of explosion engines, and by it
I am able to dispense with the gearing usually employed for the purpose of reduc-
ing the number of operations of the valve mechanism below that of the revolutions
of the engine shaft. The invention may be applied to any or all of the valves
as required; say for example the exhaust valve."
In carrying out the invention I employ an eccentric block which rotates; with
the engine shaft and in the periphery of this I form grooves or a divided groove
so arranged that at one portion of the periphery there is only a single, groove,
and at the other portion there are two, the dividing strip of metal preferably
terminating at a point at one or both ends, the eccentric block thus arranged,
operating as a cam as well as an eccentric.
The valve may be of any suitable type the mushroom type preferred-and
controlled by a spring or other means so that it normally remains in its closed
position or vice versa according to the arrangement. Between the valve and the
eccentric is arranged a tubular or other rod or equivalent which in certain positions
will engage with the stem of the valve, and under the operation of the eccentric
operate it, while in certain other positions due to the cam portion of the eccentric
this rod is moved clear of the valve stem and so does not operate the valve. The
rod may be carried in a pivotted sleeve so as to allow of the rod travelling inwards
in the sleeve, and liaving its axial plane varied by the turning of the sleeve about
its pivot. Other means may however be employed to carry this rod. The opera-
tion is as follows:-
One end of the rod engages permanently with the groove in the eccentric and
it may be retained there by a spring, a strip or gravity; this end is preferably
forked so as to obtain a suitable bearing and hold upon the block. The operation
of the eccentric as it rotates causes this rod to travel axially to and fro while the
operation of the cam groove at certain times causes the other end of the rod to
engage with the valve, and at other times to clear it thus obtaining the results
usually secured by means of toothed gearing.
I do not bind myself to employ a groove in the eccentric block so long as the
result I have described is attained. As an example of a variation, the side faces
of the block could be suitably shaped and the rod forked to correspond and thus
obtain the same result; or a raised face could be formed upon the periphery of
the eccentric.

page_text: For the purpose of operating or controlling this mechanism by or from the
governor, I may make the eccentric loose upon the shaft and by means of feathers
cause it to rotate therewith, but leave it. free to travel, longitudinally thereon,
the governor by means of a suitable jaw and grooved collar upon the eccentric or
by other suitable means causing it to travel upon the shaft. By thus moving
the eccentric the rod can be controlled so that no matter what its position in regard
to the cam it does not engage with the valve and therefore does not operate it.
The eccentric, may be similarly operated by hand, if desired.
In the accompanying drawings,
Figure 1 is a part sectional plan of the improved valve mechanism.
Figure 2 is a similar view showing the mechanism in another position.
Figure 3 is a part, sectional plan showing the position of the parts when the
governor is in operation.
Like letters indicate like parts throughout the drawings.
Upon the main crank-shaft A of an explosion engine is mounted an eccentric B
so as to revolve with the crank-shaft but be capable of movement upon the latter
in an axial' direction. Upon the periphery of the eccentric 13 is formed an endless
screw groove B' B³.
A rod C is carried in a sleeve D pivotally niounted on a bracket E secured to
the cylinder For framing of the engine. The rod C is held so as to slide longi-
tudinally to and fro through the sleeve D, and has mounted upon one end one or
more rollers C which engage with the endless screw on the periphery of the
eccentric B. A coiled spring C upon the rod C between a collar C3 on the latter
and the sleeve D tends to hold the roller C¹ always in engagement with the
periphery of the eccentric..
The valve G of the engine is of the lift type being held normally closed by a
spring G. The end of the valve spindle G is cut square as also is the end C
of the rod C, the axis about which the sleeve D can turn and the axis of the valve
spindle being also arranged so that the planes in which they lie intersect at right
angles. With the above arrangement, while the eccentric B is running normally,
that is, unacted upon by the governor, when the roller Centers the part 13¹ of
the endless screw on the periphery of the eccentric, the rod C will be brought into
line with the valve spindle G2 so that the end of the latter will be struck by the
end C of the rod C, and the valve G lifted off its seat in the manner shown in
Figure 1, When, however, upon the next revolution of the eccentric B the
roller Centers the part B2 of the endless screw, the rod C will be thrown out of
line with the valve spindle G so that the latter will not be struck as the rod C
reciprocates, the parts assuming the position shown in Figure 2..
A shaft governor H is arranged upon a fly wheel J the arms H¹ of the governor
engaging with a groove B³ on a sleeve B forming part of the eccentric B. With
this arrangement it will be seen that should the speed of the engine exceed the
predetermined limit, the action of the governor will move the eccentric B along
the shaft A in an axial direction, so that when the roller C enters the part B¹ of
the endless screw the end C of the rod C, as the latter is reciprocated, will miss
the end of the valve spindle G2 owing to the rod C being out of line with that
spindle, and in this manner the charge to the engine is cut off until the speed is
reduced.
If desired two rollers in place of the single one C, shown in the drawings, may
be mounted in a fork upon the end of the rod C in such a manner that they
follow one another in the endless screw as the eccentric revolves. The fork carry-
ing them may be pivotted upon the end of the rod C or formed integral with it
any turning movement which the rollers may require being obtained by the
movement of the rod C within the sleeve D.
Other governing arrangements may be employed if desired, and it will be
understood that the parts of the mechanism may be varied to suit. different con
structions of engine."
:

page_text: 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. A valve-operating eccentric having an endless screw formed on its periphery
for the purpose described.
2. In valve mechanism for explosion engines the combination with the main
shaft of an eccentric such as B B B upon it and a sliding pivotally-held rod' such
as C substantially as and for the purpose described.
3. Operating a valve of an explosion engine at every alternate stroke directly
from the main shaft by an eccentric such as B B B on the latter reciprocating a
sliding pivotally-held rod substantially as described.
4. The employment of an endless screw upon the periphery of an eccentric in
order to bring about the operation of a valve of an explosion engine at every
alternate stroke substantially as described.
5. Governing an explosion engine by the axial movement on the main shaft of
an eccentric such as B B B substantially as described.
6. The complete valve mechanism for an explosion engine substantially as
described and illustrated in the accompanying drawings.
Dated this 28th day of Oct 1897
JOHN VAN TOLL.
Boult & Wade
Agents for the Applicant.