Improvements in' Plate Bending Apparatus.
Year: 1896

page_text: Date of Application, 25th Sept., 1896-Accepted, 7th Nov., 1896
COMPLETE SPECIFICATION.
Improvements in' Plate Bending Apparatus.
I, JOHN FIELDING, of Atlas Works, Gloucester, Engineer, 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:-
My invention relates to apparatus for bending metal plates, constructed and
operating as I shall describe referring to the accompanying drawings.
Fig. 1 is a vertical section Fig. 2 is a part side elevation, partly in section, and
Fig. 3 a sectional plan of apparatus according to my invention, Figs. 4, 5 and 6
shew details hereinafter referred to.
From a base A extends upwards a strong framing consisting of a back piece B
and a front piece C which is bolted at its bottom to the base A and at its top to
the back B by an eye bolt D.
Between the two parts of the framing the girder E is arranged to move hori-
zontally, its bottom bearing on balls or rollers e running on the base A, and the
top guided between flanged rollers el revolving on the pin d which is engaged by
the eye bolt D.
On the back of the girder E are several inclines F and on a rod G or several
such rods are fixed corresponding inclined pieces H the lowest of which is on the
ram of a hydraulic cylinder I fixed in the base A and provided with valve I'
worked in the usual way by adjustable tappets J³ on a rod J and hand lever K.
In races between the sloping fronts of the pieces H and the slopes F and also
between the backs of the pieces H and faces L on the back frame B are inter-
posed rollers. On the back of the upright B is fixed a hydraulic cylinder M
having a yoke N connected to the girder E about its middle so as to draw it
back.
On the base A is mounted a ratchet wheel aud barrel from which a rope or
chain passes round a guide pulley P and is hooked to the hinder edge of the plate
which is to be bent. A hydraulic cylinder Q has its piston rod connected to a
pawl R which engages with the ratchet wheel.
The underside of the piston in Q is always subject to pressure and the cylinder
above the piston is put alternately in communication with the supply and discharge
of water under pressure by the valve T which is operated by the same lever K
which works the valve 12 of the main cylinder. Thus, when water under pressure
is admitted to and discharged from the main cylinder I, it is at the same time
admitted to and discharged from the top of cylinder Q. The plunger in the
cylinder M is always subject to pressure.
The apparatus operates in the following manner.
The front part of the plate that is to be bent is introduced between the curved
faces of E and C and the rope or chain is hooked to its hinder edge. The plunger
of I being then forced upwards by the hydraulic pressure, the inclined pieces H
rising with it and acting on the slopes F, cause the girder E to advance, bending
that part of the plate which is engaged between E and C; at the same time the
piston of Q is forced down lowering the pawl R. On now relieving the plunger
of I from pressure, it descends lowering the pieces H, the plunger of the
cylinder M drawing back the girder E, at the same time, the piston Q being
relieved of pressure, on its upper side ascends raising the pawl R and so turning
the ratchet wheel and barrel partly round thereby advancing the plate so as to
bring a fresh part of it into the gap between E and C to be operated on as above
described

page_text: As the stroke of the bending girder requires to be less for bending to a curve of
great radius than for bending to a curve of smaller radius, I provide an automatic
stop arrangement which acts upon and closes the supply valve of the cylinder I as
soon as the bending girder has been moved sufficiently far.
By means of a double or compound adjustment this stop arrangement can be
regulated so as to suit the movement of the bending girder to any required curve
and any thickness of plate. As shewn in Fig. 4 a screwed sleeve with hand
wheel J is screwed with threads of equal pitch upon the tappet rod J and into the
boss J which is pivotted to the hand lever K.
When the sleeve is screwed downwards the valve closes earlier and conversely.
As shewn in section Fig. 5 and elevation Fig. 6 a second adjustment is provided
by a similar screwed sleeve with hand wheel J³ which slides freely upon the tappet
rod J but is screwed into the boss on the tappet J which projects from one of the
wedge pieces H. Indicator plates and pointers are fitted to J and J* the one
being marked to correspond to different thicknesses of plate and the other to curves
of different radius.
A third screwed sleeve and hand wheel J is provided for closing the valve
when the bending girder has completed its back stroke, for the purpose of
preventing waste of water under pressure.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A plate bending apparatus constructed and operating substantially as described
with reference to the accompanying drawings.
2. In combination with the inclines on the bending girder the corresponding
slopes on the pieces moved by the hydraulic plunger, with the plane backs of these
pieces and the corresponding faces on the back frame, antifriction rollers interposed,
substantially as described.
3. The combination of the feeding rope or chain and its barrel, the ratchet
wheel pawl and hydraulic cylinder, operating the pawl, substantially as described.
4. In combination with the valve lever and the tappet on the wedge piece the
adjusting devices substantially as described with reference to Figs. 4, 5 and 6.
Dated this 25th day of September 1896.
ABEL & IMRAY,
Agents for the Applicant.