Improvements in Engine Oscillating Valves and Valve-gear.
Year: 1899

page_text: Date of Application, 23rd Oct., 1899-Accepted, 9th Dec., 1899
COMPLETE SPECIFICATION.
Improvements in Engine Oscillating Valves and Valve-gear.
I, LASZLO SZEKELYHIDY, Engineer, of Szolnok, in the Kingdom of Hungary, do
hereby declare the nature of my said invention and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement:-
The present invention relates to oscillating valve motion and consists in the
details of construction herein after set forth and particularly pointed out in the
claims.
In order to render the present specification easily intelligible reference is had
to the accompanying drawings in which similar letters and numerals of reference
denote similar parts throughout the several views.:-
-
Fig. 1 is a sectional elevation taken on the line of Figure 2 which is a
cross sectional elevation on line y-y of Figure 1, showing the valves and the
parts of the cylinders necessary to explain the invention. Fig. 3 is a part
elevation showing the driving mechanism and governor for the valves. Fig. 4
is part of a steam cylinder in elevation and longitudinal section, showing the
employment of two valves one at each end of the cylinder. Fig. 5 is a longi-
tudinal sectional elevation on the line a-a of Fig. 6, which is a cross sectional
elevation on line b-b of Figure 5, showing a modified form of the compensating
mechanism, Fig. 7 is a horizontal section on line c-c of Figure 5 and Fig. 8 is
a detail section showing the arrangement of one valve instead of two.
Referring first to Figures 1 and 2. The steam chest 1 is provided with the
ordinary ports 33 and 34 to each end of the cylinder and the exhaust port 35,
the said ports opening into a concave valve seat in which are disposed the under
valve 2 and the upper valve 6. The lower valve 2 is provided with ports 3 and 4
and exhaust port 5 in the well known manner, said ports being adapted to co-
operate with the upper segmental slide 6. These slides are oscillated relative
to each other and the steam directed alternately to each end of the cylinder and
to the exhaust in the well known manner which need not be described.
The front end of the lower valve 2 is provided with a disc 15 having a slot 16
therein in which the rectangular cross bar 17 of a hollow spindle 18 engages,
whilst the front end of the segmental upper slide 6 is provided with an upwardly
extending transverse flange 21 having rectangular slot in which the transverse
bar 24 of the spindle 23 engages. The hollow spindle 18 is provided with
packing 29 between it and the gland of the steam chest cover 19 and packing 25
is provided between the said hollow spindle and the full spindle 23 The upper
slide 6 is suspended from a compensating piston 12 by means of the connecting
piece 14, the spindle 13 passing transversely through the piston 12 and the
spindle 7 passing through the part 14 and the ends of the segmental slide 7.
The piston 12 slides in a ring of packing 11, supported in the cylinder 8 and
kept tight by means of the upper packing ring 10 which may be depressed down
on to the packing 11 by means of screws 9. One end of the spindle 7 rests
against the disc 24 of the spindle 23, against which it is pressed by a piston 26

page_text: mounted in the rear cover 27 of the steam chest and normally pressed towards
the spindle 7 by means of a spring 29 within the housing 28. By this means
the discs 15 and 21 are held tightly against their packing 20 and 25 and the
steam chest kept steam tight.
The compensating piston 12 has the effect of relieving the valve 6 of steam
pressure, since this valve will only be pressed down on the face of the valve 2
by the amount of pressure corresponding to the difference in the area of the
piston 12 and the effective area of the valve 6.
The valves are operated in the manner shown at Figure 3: the hollow spindle 18
is provided with the lever 30 and the spindle 23 of the upper valve with the
lever 31. The lever 30 is connected by means of the rod 36 to the upper end
of a rock lever 38 pivoted at 37, the lower end of which is operated by means of
the eccentric on the driving shaft in the usual manner. The lever arm 31 is
provided with a link 41 adjustable by means of the sleeve 40 and having a slide
block 44 at its free end, to which it pivoted at 43, said block being adapted
to slide in a slot 45 of a rocking lever 42 also pivotally supported at 37, and
operated by an eccentric on the driving shaft by means of the eccentric rod 49.
Eccentric rod 48 operates the rocking lever 38. At a point in the link 41
between the lever 31 and the slide block 44, a vertical lever 47 is pivotally attached
to the said rod, said lever being adjustable in length by means of the sleeve 47°
and screw threads and having its upper end pivoted to the governor lever 46
so that the action of the governor will be to vary the position of the sliding
block in the slot 45 and thus to vary the stroke of the valve 6 and the amount
of steam fed to the cylinder.
In Figure 4 a cylinder is illustrated having a separate valve for each end,
the only difference in the construction of the lower valve 2 being that the
port 4 is omitted in it at one cylinder end and the port 3 at the other as will be
easily understood.
In Figures 5 to 7 a modified method of compensating the upper valve is
illustrated. In this case the valve 50 is of a box like form having a channel 51
extending around it close to the edge said channel extending downwardly from
the top of the valve. A compensating piston 52 is provided with a depending
edge 53 and 54 all round which passes into the channel 51. At the bottom of
the channel 51 an upwardly spring pressed packing ring or ledge
55 is provided, which is normally forced upwardly by means of
springs 58 mounted in openings 57 in the valve. These openings extend through
the valve from one side to the other and allow a free circulation of steam in
the steam chest. Openings 56 also extend through the part 52 for the same
purpose. Suitable packing material, not shown, is inserted between the ring 55
and the lower edge of the depending ledge 53 of the part 52. The operation of
this valve is similar to that of the valves of Figures 1 and 2 the cross bar 24
of spindle 23 engaging a slot 59 in the end of the valve and of the compensating
piston whilst a cross bar 63 engages a slot or depression 60 in the rear ends
of these parts and is provided with a rearwardly extending pin 62 which extends
into a housing 61 mounted in the rear cover of the steam chest and filled with
suitable packing so as to form an equivalent for the spring pressed piston 26
of Figures and 2. By this arrangement the steam will have access through
the passages 57 to the under side of the packing ring 55 and will force this
and the upper or compensating piston upwards and the piston 50 downwards
on to the face of the valve 2. Thus it will be seen, that since the compensating
piston closes against the top of the steam chest the only steam which will be
effective in pressing apart the two parts of the piston is that which has access
to the lower surface of the packing ring 55. In this construction the valve. 50
may be employed alone, without the valve 2, as illustrated at Figure 8, but it
should then be provided with an exhaust port as indicated at 64.
The steam feed to the cylinder may also be regulated by hand by means of the
sleeve 47 of the rod 47.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1: Compensated oscillating slide valve motion having a lower valve (2)
operated by a rectangular cross bar (17) and lever (30) attached to the hollow
spindle (18) having further a shaft (7) forced against the spindle (23) by means
of a spring pressed piston (26), an upper segmental valve (6) with actuating
cross bar (24) and lever (31) on spindle (23) and a compensating piston, moving
in packing rings (8 10), and having suspended thereon by means of a spindle (1:3)
and the hanger (14), the upper slide valve (6), substantially as described.
2: A modified form of the compensating mechanism covered by Claim 1:
consisting of the piston (50) having openings therethrough and having a canal
around its edges extending downwardly from the top, a packing ring supported
near the bottom of the said canal and being normally spring pressed upwardly
and an upper piston part (52) having depending ledges to extend into said
channel, and closing against the top of the steam surface, and inlet orifices to
allow the steam access to the lower surface of the spring retained packing ring
substantially as described.
3: The actuating mechanism for the oscillating valves covered in Claims 1
and 2 consisting of the levers 30 and 31, pivotally mounted rocking levers 38
and 42 actuated from the main driving shaft eccentrics, a rod to connect lever 30
to its rocking lever 38 and a rod 41 adjustable in length and having its forward
end pivoted to a slide block 44 to connect the lever 31 with the slot in the
upper end of the rocking lever 42, and means in connection with the governor
lever, to vary the position of the slide block 44 in the slot 45 according to the
position of the governor lever substantially as described.
1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C..
13, Temple Street, Birmingham, and 25, Cross Street, Manchester,
Agents.