Year: 1888

page_text: Date of Application, 1st Feb., 1888
Complete Specification Left, 1st Nov., 1888
Complete Specification Accepted, 7th Dec.,
188
1 WILLIAM BELLBY AVERY, Scale Beam Manufacturer, of 12 Digbeth, Birmingham
in the County of Warwick, do hereby declare the nature of this invention to he as
follows :-
--
This invention consists in a novel mode of forming the knife edges for scale beams,
steelyards, and weighing machines, and in the mode of fitting and adjusting the same
thereto, the object being to simplify the fitting and adjusting, and to obviate the
necessity for hardening the centres after fitting, but before adjusting or setting.
In carrying out this invention, I form each centre of a block of steel of suitable
length, heart shaped in cross section, the point serving for the knife edge. This block
is slotted or grooved across its upper part at right angles to the knife edge, and in
this slot or groove the beam is secared. Through the lugs or ears formed by slotting
or grooving the block, holes are drilled parallel with the knife edge to receive rivets
by which the centres are secured to the beam or steelyard.
The centre block is next hardened and ground true, and is then ready to be fitted
to the beam or steelyard. The beam is machined down to exactly fit the slot, and the
end centres are then rivetted in position.
The middle centre, which is tlie one that has to be adjusted to the beam, is formed
with a central and oval hole or slot, and the beam as near to its centre of oscillation
as possible is tapped to receive two set screws, one on either side, which pass through
the oval hole or slot. When the centre is fitted onto the beam, the set screws are
screwed up nearly tight, and the beam is set up to be adjusted.
The adjustment is made by gently tapping the centre in one direction or the other,
and when the adjustment is obtained, the set screws are tightened and the beam is
taken to have the rivet holes drilled, the holes in the centre serving as bushes. When
drilled, the holes are rimered, the rivets are put in, and rivetted, and the beam is.
finished.
If the knife edges are not exactly in line, a small piece of packing is placed in the
centre under the beam during the adjustment.
1000

page_text: COMPLETE SPECIFICATION.
Improvements in Scale Beams, Steelyards, and Weighing Machines.
I WILLIAM BEILBY AVERY, Scale Beam Manufacturer, of 124 Digbeth, Birmingham
in the County of Warwick, 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 consists in a novel mode of forming the knife edges or centres for
scale beams, steel-yards, and weighing machines, and also in the mode of fitting and
adjusting the centres to the beams, the object being to simplify the fitting and
adjusting, and to obviate the necessity for hardening the centres after fitting, but
before adjusting or setting, as heretofore.
In carrying out this invention, I form each centre of a block of steel of suitable
length, heart shaped or triangular in cross section, the point of the heart serving for
the knife edge. This block is slotted or grooved transversely at its upper part, or at
right angles to the knife edge, and in this slot or groove the beam is secured by means
of screws or rivets.
•
The beam being machined down to exactly fit the grooves, the centre, which has
to be adjusted, is secured approximately in position by a set screw on either side of
the beam.
The adjustment is made by slightly moving the centre in one direction or the other,
and when the adjustment is obtained, rivet holes are drilled in the beam, and the
centre is rivetted thereto.
In the accompanying drawing:
--
Fig. 1 shows in side elevation the arrangement of an end centre or knife edge for
carrying the scale pan or weights.
Fig. 2 is a plan view, and
Fig. 3 is an end view.
Fig. 4 is a side elevation, showing the arrangement of the middle or main centre
or knife edge on which the beam oscillates.
Fig. 5 is an under side plan, and
Fig. 6 a cross section of the beam in the line cx, Figs. 4 and 5.
A is the beam of the weighing machine, B the centres or knife edges, which may
be heart shaped (see Figs. 1 and 4), or triangular in end view.-The blocks of which
the centres are formed are recessed or grooved transversely to receive the beam (see
Figs. 3 and 6), and the lugs B' thus formed are drilled to receive the rivets B² by
which the centres are secured to the beam.
Referring now to Figs. 1, 2 and 3, the centres are placed on the beam at the
. proper position, and-the-rivet- holes are drilled in the beam; the holes in the centres
serving as bushes. The rivets are then inserted and secured. The adjustment of the
end centres is unnecessary, as all adjustment can be effected by the third centre.
Referring now to Figs. 4, 5 and 6, the centre will be formed, in addition to the
rivet holes, with a central tapped hole C (see Fig. 4), and will be provided with set
screws.

page_text: To prepare for adjustment, the centre is placed on the beam, and is secured thereto
by screwing up the set screws nearly tight. The beam is then set up for adjustment,
which is effected by moving the centre slightly in one direction or the other, as the
case may be. The set screws can he lightly secured in order to make the adjustment
easy. When accurate adjustment is obtained, the set screws are tightened up, so
that the centre shall not move, and the beam is then taken to the drilling machine to
have the rivet holes drilled, the holes in the block forming bushes. When drilled,
the holes are rinered, the rivets put in and rivetted, and the beam is finished.
The blocks for the centros are bardened and ground true before they are fitted to
the beam.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. Forming the centres or knife edges as herein shown and described.
2. The mode of fitting and adjusting the centres or knife edges to the beams of
weighing machines as 'herein shown and described.