AN IMPROVED COMBINED SLIDE- BLOCK AND CROSS-HEAD FOR STEAM AND OTHER ENGINES
Year: 1880

page_text: LETTERS PATENT to John Thomas Abell, of Cannon Street, in the City of
London, Engineer, for an Invention of "AN IMPROVED COMBINED SLIDE-
BLOCK AND CROSS-HEAD FOR STEAM AND OTHER ENGINES."
PROVISIONAL SPECIFICATION left by the said John Thomas Abell at the
Office of the Commissioners of Patents on the 16th January 1880.
JOHN THOMAS ABELL, of Cannon Street, in the City of London, Engineer.
"AN IMPROVED COMBINED SLIDE-BLOCK AND CROSS-HEAD FOR STEAM AND OTHER
ENGINES."
The object of this Invention is to effect a simple and cheap combined slide-block
and cross-head for engines, and so to arrange the parts thereof as to produce the
free and easy working thereof, and to facilitate the repairing, cleaning, and oiling
the same.
My improved combined cross-head and slide-block is formed of two suitable
pieces of iron securely bolted together by a screw-bolt and nut; the underside of
the upper piece is planed even; the lower piece in its cross-section somewhat
resembles that of channel-iron, except that its flanges project or open outwards,
thus making the inner angles thereof obtuse. The whole of the outer surface of
this lower piece is properly planed so that it may fit and slide freely, it is then
bolted to the said upper piece. The lower part of the said upper piece overlaps the
under piece of such slide-block, thus forming two acute angles, one on each side
thereof. In these angles the slide bars of the engine are fitted, which slide bars are
cast with and form part of the engine bed. By this method the said slide-bars
form a wedge-shaped space or opening, wherein works or slides the flanges of the
said lower piece, thus constituting the working surfaces of the slide-block.
When either of the said surfaces or the surfaces of the said slide-bars are worn
away, by simply withdrawing the bolt which joins the said upper and lower pieces
together, and thus separating them, the upper surface of the under piece of the
slide-block can be filed or otherwise reduced to the level of the worn surfaces of the
upper part of the slide bars, so that when the said two pieces are again bolted
together the slide-block will fit as when first made.

page_text: The piston-rod of the engine is keyed into the upper piece of my improved slide-
block and cross-head, thus causing the centre of such piston-rod to be slightly above
the slide-bars of the engine bed.
On the upper part of the slide-block are two ears, in one of which I pivot by a
pin the connecting-rod of the engine, the centre of which pin is in the same plane
or at the same level as the centre of the said piston-rod and a little above the
slide-bars, by which arrangement the gland and stuffing-box of the piston-rod can
easily have attention at any time, and the several parts thereof be cleaned and oiled
with facility as required.
Oil is supplied to the sliding surfaces by two syphons or cups cast with and on
each side of the said upper portion of the slide-block.
These improved arrangements form a cheap, thoroughly substantial, and compact
slide-block and cross-head together, which can be taken to pieces and put together
again by any ordinary engine-man or even by a lad, and the several parts can with
ease and facility have prompt attention and be kept in good working order without
interfering with any other portion of the engine.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Thomas Abell in the Great Seal Patent Office on the 7th
July 1880.
JOHN THOMAS ABELL, of Cannon Street, in the City of London, Engineer.
'AN IMPROVED COMBINED SLIDE-BLOCK AND CROSS-HEAD FOR STEAM AND OTHER
ENGINES."
The object of this Invention is to effect a simple and cheap combined slide-block
and cross-head (hereinafter designated "slide-block") for engines, and so to arrange
the parts thereof as to secure the free and easy working thereof, and to facilitate
the repairing, cleaning, and oiling the same.
In order that my said Invention may be more fully understood and be more
readily performed, I will explain the same with the aid of the accompanying
Drawing, which forms part of this Specification, reference being made thereto by
the numerals and letters marked thereon. The same index letters refer to the same
parts in each Figure of the said Drawing.
Fig. 1 is a side elevation of my improved slide-block; and Fig. 2 is a plan
thereof; Fig. 3 is an end elevation and part cross-section of the same on the
line A, B, Fig. 1.
My said improved slide-block is formed of two suitable pieces of iron a, b, secured
together by the screw-bolt c and lock-nuts c¹; the underside of the said upper
piece a is planed even; the said lower piece b in its cross-section somewhat
resembles that of channel-iron (see Fig. 3) except that its flanges project or open
outwards, as shown, thus making the angles thereof at 61 obtuse. The whole of
the outer surface of the lower piece b is properly planed so that both pieces when
united may fit accurately and slide freely upon and against the engine-bed d. The
lower part of the said upper piece a overlaps the under piece b, thus forming there-
with two acute angles, one on each side at a¹. In these angles a¹ the slide-bars d'
of the engine are fitted, which slide-bars d' are cast with and form part of the
engine-bed d, as shown in Fig. 3. By this method the slide-bars d form a wedge-
shaped or tapering opening, wherein works or slides the flanges of the said lower
piece b.
When the sliding surfaces of this improved slide-block or the surfaces of the
slide-bars d' are worn away, by simply withdrawing the bolt c which unites the
said upper and lower pieces, and thus separating such pieces, the upper surface of
the piece b can be filed or otherwise reduced to the level of the worn surface.of
the upper part of the slide-bars d¹, so that when the pieces a and b are again
bolted together the slide-block will fit and work as when first made.
The piston-rod e of the engine is keyed to the upper piece a so as to place the
centre of such piston-rod slightly above the slide-bars d of the engine bed.
On the upper portion a of the slide-block are two ears fin which I pivot by a
pin the connecting-rod fi of the engine, the centre of which pin is in the same
plane or at the same level as the centre of the piston-rod e, and consequently a
little above the slide-bars d', by which arrangements the gland and stuffing-box of
the said piston-rod and connecting-rod pin can easily have attention at any time,
and the several parts thereof be cleaned and oiled with facility as required.
Oil is supplied to the sliding surfaces by two syphons or oil-cups g cast in the
said upper portion of the slide-block, as shown.
These improved arrangements form a cheap, thoroughly substantial, and compact
slide-block and cross-head together, which can be taken apart and put together
again by any ordinary engine-man, or even by a lad, and the several parts can with
ease and facility have prompt attention, and be kept in good working order without
interfering with any other portion of the engine.

page_text: Having thus fully described and ascertained the nature of my said Invention
and the method of performing the same, without restricting myself to the precise
forms and relative dimensions of the several details now illustrated, I claim as my
Invention and desire to secure by the herein before-mentioned in part recited
Letters Patent,—
Firstly. The shape or form of the lower piece b of the slide-block, substantially
as described and shown in transverse section in Figure 3.
Secondly. The form of slide-bars and engine bed together, substantially as
described and shown in transverse section in Figure 3.
Thirdly. The method of uniting the upper and lower pieces of the said slide-block
by a separate or disunited bolt c, substantially as described and shown in the
Drawing.
Fourthly. The arrangement and combination of the several parts of the said
slide-block and the slide-bars, substantially as described and shown in the Drawing.
In witness whereof, I, the said John Thomas Abell, have hereunto set
my hand and seal, this Twenty fourth day of June, in the year of our
Lord One thousand eight hundred and eighty.
J. T. ABELL. (LS.)