IMPROVEMENTS IN THE CONSTRUCTION OF BOXES MADE OF TIN OR OTHER METAL PLATE, AND APPARATUS FOR EFFECTING THE SAME
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Jabez James at the Office of
the Commissioners of Patents, with his Petition, on the 28th April
1.871..
I, JABEZ JAMES, of 40, Princes Street, Stamford Street, Lambeth, in
the County of Surrey, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF BOXES MADE OF TIN
OR OTHER METAL PLATE, AND APPARATUS FOR EFFECTING THE SAME," to be as
follows:-
Shallow boxes or the lids of boxes made of tin or other sheet metal as
ordinarily constructed have flanges or lips bent up at the sides and ends,
and the angles where the side and end flanges meet are usually secured
by soldering a flap of the one to the other.
The object of my Invention is the jointing of the one flange to the
other at the angle without soldering, and apparatus for effecting the
same.
The improved joint consists of a flap of the one flange bent over the
other flange, the end of this flap being passed through a slit in that
flange and bent back on the other side so as to form a hook. For
making this joint I in the first place prepare the sheet intended to form
the box or lid by cutting it to suitable shape and dimensions and cutting
out pieces at the angles so as to leave the required flaps; also making

page_text: the slits into which these flaps have to be inserted, and bending up the
flanges at the sides and ends. This part of the process is usually effected
by punching, and being employed for boxes or lids jointed in the ordinary
way forms no part of my Invention.
Having thus prepared the sheets I operate on them by the improved
apparatus which I will now describe:-It consists of a slide moved to
and fro in guides by a crank, eccentric, cam, or other convenient means.
The end of this slide is formed with projections upon it, one beyond the
other like steps, and fronting tliese several steps there are sliding bolsters
pressed towards the slide by springs or weights or moved towards or
from it by cams suitably timed to the movement of the slide. The
flange of the sheet to be operated on is inserted between the front of
the slide and these bolsters when the slide is in the back part of its
stroke. The slide advancing bears the flange against the bolsters, and
the successive projections acting on it in conjunction with the successive
bolsters cause successively the point of the flap of the flange to be bent,
then the bent point to be inserted into the slits of the other flange, and
finally that point after being passed through the slit to be bent or looped
over so that it is securely held in the slit, and thus one of the angles of
the box or lid has its side and end-flanges-securely-jointed together.
During the operation the sheet is held down by fingers acted on by cams,
and when the operation is completed these fingers are withdrawn and
a stirrup advances, which throws off the sheet from the machine. By
making the slide face of suitable width and providing it with two
symmetrical sets of projections, and mounting two sets of bolsters to face
them, two of the angles can have their jointing effected simultaneously,
and with a second slide with such duplicate projections and bolsters to
correspond the four angles can be jointed at once. The position and
form of the projections on the slide and of the bolsters are made
adjustable to suit various dimensions of lids or boxes.
Instead of forming each joint with only one flap there may be several
flaps each hooked as above described into slits provided to suit them
in the other flange, and thus the angles of deeper boxes or lids can be
jointed in like manner.