for traction engines for Traction Engines.
Year: 1898

page_text: THOMAS HURST, Broadhurst Farm, Clifton, near Manchester, Engineer, do
hereby declare the nature of this invention to be as follows:-
An improved road wheel for traction engines.
Having a cast iron rim with dovetailed slots running diagonally across to
receive wood blocks driven into same the said blocks to project so that the engine
travels entirely on wood so as to do no damage to roads.
The said dovetails to be as near together as possible consistently with strength.
Doted this 8th day of Wal 1900
An improved Road Wheel for Traction Engines.
I, THOMAS HURST, of Broadhurst Farm, Clifton, near Manchester, in the
County of Lancaster, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
accertained in and by the following statement and accompanying drawings:-
My said invention relates to road wheels for traction engines of the type which
are provided on their peripheries with blocks of wood to afford a better gripping
surface and render them less liable to injure the roads. The object of my inven-
tion is to simplify the method of securing such wooden blocks firmly in position
and at the same time to increase the utility of the blocks. This I effect by
arranging the blocks diagonally across the periphery of the wheel, preferably
on their ends so that the grain of the wood is disposed vertically to the periphery
of the wheel.
The blocks are forced within diagonal dovetailed or undercut recesses formed
in the rim of the wheel.
And in order that my invention may be fully understood I have attached
hereto a sheet of explanatory drawings to which I will now refer.

page_text: Fig. 1 of the drawings shows in perspective view a road wheel for a traction
engine fitted with wood blocks in accordance with my invention.
Fig. 2 is a plan of a portion of the wheel rim showing the diagonal arrange-
ment of the wood blocks.
Fig. 3 is a sectional elevation of two of the blocks and a portion of the rim on
the line A B Fig. 2.
Figs. 4 to 6 represent a modification of my invention.
Referring in the first place to Figs. 1 to 3 1 cast the rim a of the wheel with
any suitable number of dovetail or undercut recesses in its periphery as shown
in Fig. 3. These recesses are arranged diagonally across the periphery of the
rim at any convenient angle, say at about 20° although I do not confine myself
to this. The dovetail recesses, as will be more particularly seen from an in-
spection of Figs. 1 and 2, do not extend completely across the width of the rim,
the metal thus left at each end of the blocks forming a stop to prevent their
lateral movement. The blocks of wood, or it might be of other suitable
material such as woodite or other non-metallic substance are formed with
straight sides and of a width equal to the outside aperture of the dovetail recesses.
One block only or any suitable number of blocks may be used to fill the under-
cut recess, three being shown in the drawings.
The blocks are arranged on end, that is, with their grain about radial with
the axis of the wheel as shown more clearly in Fig. 3 whereby the wear resisting
properties of the wood blocks are greatly increased. The blocks bare forcibly
hammered into the undercut recesses.
Under the compression requisite to enable this to be done, tlie wood is
expanded and completely occupies the dovetailed gaps formed in the rim as
shown in Fig. 3 and is thus securely held in position therein. If desired how-
ever, I might positively lock the blocks within the dovetailed recesses in the
rim a by means of a bolt c (Fig. 2).
The dimensions of the blocks 6 are arranged so that a little more than half of
their depth protrudes beyond the metallic rim.
To prevent injury to the edges of the blocks on their coming into contact
with the ground I arrange between the blocks b wooden packing pieces d pre-
ferably cut with the grain of the wood longitudinal as shown in Figs. 1 and 2.
The packing pieces d may be secured to the blocks b by means of pins e sec
Fig. 2.
In a modification of my invention shown in Figs. 4 to 6 I cast the rim so as
to leave one end of each dovetail recess open as shown in Fig. 5. In this case
the recesses may be slightly tapered in the direction of their length as shown
in Fig. 4 and the wooden block, or blocks, correspondingly tapered and driven
in the rim from the open end, the tapered end of the blocks being first introduced
within the undercut recess to facilitate the operation. A wrought iron ring f
is then bolted upon the side of the rim so as to surround the open ends of the
dovetailed gaps and thus secure the blocks in position. The ring f may be
in segments if desired for convenience in fitting. The blocks are arranged on
their ends, and packing pieces d with the grain horizontal are disposed between
the blocks as already described with reference to Figs. 1 to 3.
•
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) In road wheels for traction engines the employment of wood blocks arranged
diagonally within undercut diagonal recesses formed in the rim of the wheel
substantially as described and shown.
2) In road wheels for traction engines forming the rim of the wheel with
diagonal undercut or dovetail recesses and forcing within the recesses wooden
blocks arranged with the grain vertical to the periphery of the wheel or about

page_text: radial with the axis of the wheel the spaces between the blocks being filled with
packing pieces of wood in the manner and substantially as described and
illustrated.