Improvements in or relating to Clamps or Joints for Boxes and the like, of Cardboard, Leather, Wood or Similar Material.
Year: 1897

page_text: Date of Application, 1st Jan., 1897-Accepted, 7th Aug., 1897 _
Improvements in or relating to Clamps or Joints for Boxes and the
like, of Cardboard, Leather, Wood or Similar Material.
A communication from CARL DAVID AND SON, of I Meszarosuliza 38, Budapest,
Hungary, Manufacturers of cardboard articles
I, ALFRED JULIUS BOULT, of 111 Hatton Garden in the County of Middlesex,
Chartered Patent Agent, 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:-
The present invention relates to clamps or joints for boxes of cardboard, leather,
wood or similar material, which are manufactured from strips of material in
lengths corresponding to the width of the box or in continuous lengths.
The clamping strips hitherto used may be divided into two main classes the
earlier ones being characterised by the direction of pull or strain on the clamp-
connection being normal to the plane of the bent clamp points whereas in the
second class the plane of the holding points was parallel to the direction of the pull.
This is illustrated respectively in Figures 9 and 10 of the accompanying drawings,
in which the clamps are supposed to be removed from the joints formed by them,
so that the holes made by the points are visible. The arrows indicate the direc-
tion of the pull acting on the joint.
These two systems of clamps have great disadvantages, one being that cuts in
a straight line are conducive to breaking of the material along that line especially
so in boxes made of inferior card-board, or wood, when the direction of the fibres
of the latter coincides with the line in which the cuts are made. In joints of
the second class, their strength is impaired by the points splitting or cutting the
material injuriously in cases where inferior cardboard or wood the fibres of which
have the same direction as that of the clamp-points is employed.
The clamps forming the subject of the present invention are, on the contrary
provided with points arranged so that they neither lie in one line nor can the
prints cut or split the material. A suitable arrangement is shown in the same
manner as Figures 9 and 10, in Figure 11 in which they form an interrupted or
broken zig-zag line, whereby the box material is impaired as little as possible and
moreover the strain acts against the surface of the points and not against their
ege. They form therefore a connecting link between the two well-known systems
and combine the advantages of both without having any of their disadvantages.
A breaking line is not formed owing to the distance of the holes for the clamping
points from each other and to their oblique position and the beginning and the
end of one hole being at different distances from the edge of the material.
The new clamping stips are shown in Figures 1 to 4 and 7 and 8 the two latter
showing them on an enlarged scale in order to better illustrate the manner of
forming the clamping points. The manner of employing them is clearly shown in
Figures 5 and 6.
As shown in these figures the clamps consist of a central main part a with lateral

page_text: square or rhomboidal projections b the spaces c between being also square or of
any other shape. The points e of the clamping strips which penetrate into the
box material are formed on the outer edges of the projections b their bases being
shorter than the edge of the projection so that they do not join at the point of
the projections b. Their points liefore they are bent at right angles to the surface
of the strip, lie approximately in line with the outer corners of the projections the
right hand point of one touching the left hand point of the next clamp. After they
have been bent the points of the clamps become equally distant from each other so that
the holes which they cut on the card-board or other material are uniform and
regular along the edge.
A further advantage which must not be undervalued is that in consequence
of the oblique position of the points relatively, to the central axis of the strip
although said points when driven into the material bend back somewhat in the
shape of a hook they never bend flat before penetrating into the material as often
occurs, with the clamps illustrated in Figure 9.
..
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondent and in what manner
the same is to be performed, I declare that what I claim is:
}
1. A clamping strip or joint for boxes and the like of cardboard, leather, wood
or similar material wherein the points of the clamps are formed on the outer edges
of lateral square or rhomboidal projections formed on the strip so that their bases
do not touch and so that the points bent at the right angles to the plane of the clamp-,
ing strip are in a non-continuous zig-zag line and are approximately equidistant
from each other and are at an oblique angle to the central line of the strip to the
direction of pull or strain on the completed joint.
2. A clamping strip or joint for boxes and the like substantially 'as described
and illustrated in Figures 1, 2, 3 and 4 of the accompanying drawings.