Improvements in Wood Screw Cutting Machines.
Year: 1894

page_text: Date of Application, 20th Aug., 1894-Accepted, 5th Jan., 1895
Improvements in Wood Screw Cutting Machines.
I HERMANN WEILAND of Barmen, Bethovenstrasse 32, Rhenish Prussia,
Germany, Mechanical 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 :-
This invention has for its object to produce wood screws from wire nails, which
are properly shaped and provided with a suitable head, in such a manner that the
slot for turning the screw is cut in first into the head and then the stem of the nail
is provided with screw thread, but all in the same machine, so that the finished
wood screw is turned out of the machine.
The machine is shown on the accompanying drawing on which
Figure 1 is a top view ;
Figure 2 is a side view seen from the right side of Figure 1;
Figure 3 is a horizontal section of the tong arrangement.
Figure 4 is a side view of Figure 3;
Figure 5 shows the device for working the head;
Figure 6 shows the arrangement of the support of the thread-cutting chisel and
for cutting the point ;
Figures 7 and 8 is the device for cutting the slit into the head;
Figure 9 is a vertical cross section along line 1-1 of Figure 1.
a is the main shaft of the machine, it is carried in the frame b and receives its
motion from a pulley 1; n shaft a is losely held a box 2, which I shall describe
more fully when explaining the tong arrangement for holding the screws, which is
actuated by a toothed wheel 3 keyed on shaft a.
At the left end of the shaft a is also fixed a small wheel gearing into the wheel 4
(Figure 1), which is keyed to a small shaft c carried in the frame bat d and in a
bridge e. The shaft c carries the chain wheel 5, the conical wheel 6 and the cam
disc 8 (Figure 1).
The chain wheel drives the saw of the apparatus for cutting the slit into the
head and which I shall describe more fully further on, by means of the shaft 9 and
the conical wheels 10 and 11 (Figures 2 and 9).
On shaft c is also keyed a conical wheel 6 gearing into a similar wheel 7 on a
spindle 12 and a cam 8 on same shaft works upon a bar 23, to which is fixed the
holder 24 for the chisel (Figures 1, 6 and 9) for cutting the screw thread.
At one end of a bar 27 is keyed a bell-crank lever 27ª (Fig. 2) pressing with one
arın against a piece 27°, into which is cut a recess 27d and which forms a part of
the cam 8. This bar is caused to oscillate by the combined action of the piece 27°
and the spring 27b fixed at the end of the other arm of the lever 27ª. At the other
end of the bar 27, at the right side in Fig. 1, is held a piece 28 formed in
steps; this piece can be shifted lengthways on the bar by the following means:
To the left side of the piece 28 is put a ratchet wheel 29; a pawl 28ª on the
piece 28 causes the ratchet to be turned gradually; a counter pawl 28° preventing
its going back, now the left face of the boss of the ratchet wheel 29 is made
screw shaped and it faces a corresponding piece 29", which is held fast on the
frame of the machine, therefore when the bar 27 is turned round gradually with the
piece 28 upon it this will be shifted lengthways at the same time towards the right
together with the ratchet wheel 29 on account of the screw shape of the face of the
latter. A spring 28 pushing it towards the left again when it has made one revolution.
PD031

page_text: The piece 28 acts upon the lever 26 which by rising gradually upon the steps
on 28 governs the chisel in respect of its position when cutting the thread and thus
the depth of the cut is regulated.
l
The spindle 12 named above is journalled in bearings fand upon the frame b;
it lies at right angle to the main shaft a; a worm keyed upon this spindle causes
a shaft g to be turned by gearing into the worm wheel 15, which is keyed upon the
shaft g.
This shaft is carried in bearings h, i and k.
At the end of the spindle 12 is also keyed a cam disc 13 which actuates indirectly
the feeder. This is done as follows: The disc is provided with a projection and
this presses against the short arm 100 at the end of the bar 101 and thus pushes
the bar towards the right. Now a disc 103 at the side of the wheel 18 acts upon
a bent lever 102 and thus causes the bar 101 to oscillate with the lever 21 keyed
thereon. This lever serves to hold the arın 104 which is linked thereto at its outer
end 105. On bar 101 is also keyed a three armed lever 106 (a, b, c) opposite to the
disc 17; the arm 106 reaches below the disc 17 and causes also a to and fro motion
or oscillation of the lever; a spring fixed to the end of the arm 106" presses the
end of the arm 106 continually against the circumference of the disc 17. To the
arm 106 is connected a bar 107, which is linked to the arm 104, the end of which
is provided with knippers, which take the screw nail coming from the slotting
apparatus, as shown in Fig. 9, so that it can be brought to the tongs where the head
is worked and the thread is cut.
I will now explain how the blanks are taken from the slotting device and brought
into the tongs and how at the same time the finished screws are taken from the
tongs and how they are carried away out of the machine.
The disc 103 rises the lever 102 a little and thus also the lever 21 ; by this
movement the blank held by the upper nipper on arm 104 is raised a little above
the channel of the slotting device, and by the action of the disc 17 upon the
lever 106 the bar 104, which holds the blank, is brought in a vertical position just
above the tongs. A projection on disc 103 acting upon the arm 102 causes the
lever 21 to be lowered a little and consequently also the arm 104 and now the
lower nippers take hold of the finished screw in the tongs which is opened. Mean-
while a projection on the disc 13 has pushed the har 101 towards the right and all
the parts fixed thereto, the lever 21 and the arm 104 with the screw held by it.
By this movement towards the right the blank held also in the upper nippers pushes
against a fixture suitably arranged in the machine and it therefore is shifted towards
the left with regard to the nippers.
By the action of the disc 103 upon the lever 102 the lever 21 and arm 104 are
lowered so much that the blank is brought central to the tongs and a spring draws
the bar 101 then towards the left and thus the blank is put into the tongs which are
now closed. A spring 21 now pulls the lever 21 upwards, the disc 103 allowing this
movement and the arm 104 is also raised with the screw held by its nippers. The
disc 17 now acts again upon the lever 106 and brings back the arm 104 into the
starting position shown in full lines in Figure 2 and during this movement
the finished screw held in the lower nippers on 104 is stripped off and falls out of
the machine; a new blank is taken from the slotting apparatus and the same
operations as described above begin anew.
At the left end of the shaft is keyed the excentric disc 14 (Figure 1, 5) for
setting in motion the rack 56, which serves for actuating the tool shaping the heads
of the screws as will be more fully explained hereafter. A grooved disc 16 upon
same shaft causes the opening and closing of the tongs, and a disc 17 sets in motion
the feeder as explained before, whereas a cone wheel 18 gears into a cone wheel 19
for turning the plate 20. The boss of the wheel 18 is formed into a peculiarly
shaped disc serving to press down the arm 21 of the feeder, whilst it is pulled
upwards by a spring 21".
A cam disc 22, at the right end of shaft g, actuates the device for cutting the
pointed end of the screw.
A small triangular chisel held in the toolholder 30 (Figure 1 and 6) cuts first

page_text: said pointed end. The holder is fastened to the bar 31, which can be moved
radially and axially.
The radial motion is caused by an inclined plane 32 (Figure 1), upon which
slides a projection of the holder. The axial motion is done by an
arm of the
forked lever 33, with which the bar 31 is so connected, that the latter can be
turned. The forked lever 33 receives its motion from the grooved cam disc 22.
The device making the slot into the heads of the screws is arranged as follows:
A box 34 (Figures 1, 2, 7 and 8) is provided at both ends with a recess or curved
way 35, at the left side the recess has the shape of a screw head, at the other side it
corresponds to the stem of the screw; the recess is so formed that the screw nails
or blanks can slide therein (Figures 7 and 8); at the bottom side it is straight and
horizontal and it ends in a receiving arm; opposite to the straight part is arranged
the saw 36. A cross 37 carries the nails forwards in the recess 35 along the saw,
where they are provided with the slot and they are thence conducted into the
receivers.
The cross is set in motion on its spindle 39 by a ratchet wheel and pawl 38 by
means of the rod 40 and lever 41 (Figure 1 and 2), from the grooved disc 22, in
ratio to the working speed of the inachine.
The tongs or nippers consist of a mandrel 42 carried at m on the frame b
(Figures 1, 3 and 4) in which the round bar 43 is held excentrically but so that it
can be turned round. To the mandrel 42 is fitted the box 44 of the tongs; at the
left side it forms a toothed wheel 45 and at its right side a head 46 is put thereon;
it ends at the left end at m and at the right side at a nut 47 screwed upon the
mandrel.
The head 46 carries the legs 48 of the tongs (Figures 1, 3 and 4) so that they
can be moved; they are held by screws 49; at the right side they are provided
with adjustable cheeks 50 and at the left side they reach into the clamping disc 51,
wich is provided with corresponding openings; the clamping disc can be shifted
upon the box 44 and turns round with it; at its left side it is provided with wedge
shaped prolongations, so that the pressure upon the legs 48 can be applied in a
practical manner.
These projections slide in grooves of the box 44 (Figure 3), so that when the
clamping disc 51 is shifted towards the left side, the legs approach each other and
the tongs are opened and vice versa and in the latter case the tongs hold a screw
nail put between them very firmly and fast.
The movement of the clamping disc is caused by a three armed lever 52
(Figures 1, 3 and 4,) the central arm of which is fork shaped, the two other arms
of the same form an obtuse angle and at their ends they are provided with little
rolls and they are of unequal length; the box 2 actuates upon the ends of the
lever and it is provided at its ends with discs having spiral projections formed at
their inner sides which stand apart from each other a little more than the length
of both levers. An oblong hole 2ª is cut into the box which allows its axial motion
on shaft a, which however is limited by a pin 2 driven fast into the shaft (Figures 3)
so that the box is taken round with the shaft a.
When the machine is at work the box 2 is shifted as required, by means of the
grooved disc 16 and a connecting lever 16 shown in dotted lines in Figure 1, it
causes the three armed lever 52 to be moved to and fro and thus shifts the clamping
disc 51 on its shaft by the forked part of said lever; in consequence of which
movement the tonge are opened and closed.
The tongs are made to rotate by the wheel 3, driving by means of an intermediate
wheel, the wheel 45 (Figure 1).
From Figures 1 and 3 it will be seen that there is a considerable space between
the cheeks of the tongs and into this space I place the device for turning the heads
of the screws.
To the clamping piece 53 is fixed the shaping tool 54 (Figures 1, 3 and 4) at the
right end of the bar 43. A small gear wheel 55 (Figures 1 and 5) at the left end
of the bar and set in motion by the rack 56, which itself moves to and fro by the

page_text: cam disc 14, causes the shaping tool to be brought in contact with the head of the
screw blank so that this will be worked and shaped.
The face of the wheel 55 and that of the clamping piece facing each other are
screw shaped and corresponding to them is made the end of the mandrel and this
causes the whole device to be shifted towards the right while it rotates and thus
the upper face of the screw head is turned.
The chisel approaching the head of the screw in a curved line prevents the
breaking out of the edges and corners of the head at the slot.
The machine works in the following manner:
The screw blanks or nails are put into the plate 20, which is turned round against
a fork going up and down; the blankes are caught by the fork at their head and
when it is raised, they slide down along it into a channel as is generally the case
with these machines and I have therefore not given a detailed description of this
part of it, the same being old and well known. From this channel they are brought
automatically into the box 34 for cutting the slot and thence they are taken up by
the receiver, which carries it to the tong where it takes first away the finished
screw in order to be able to put in at the same time the new blank. On its way
back to the box 34 it deposes the finished screw.
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 a machine for making wood-screws a tong by means of which the nail or
screw blank can be so held that the hea of the screw and also the screw thread
can be worked simultaneously without changing their place; the opening and
closing of the tong being done automatically without the use of springs by shifting
a clamping box lengthways.
2. In a machine for making wood screws a tong in which the device for working
the head of the screws is lodged between the legs or jaws of the tong.
3. In a machine for making wood screws the device for cutting the slot into the
screw head:
box (34) having curved recesses (35) in which the
otting the slot.
blanks are taken up and carried aci
The whole as set forth and as illustrated.
DL 101 c
HERMANN WEILAND,
Per Karl J. Mayer,
Agent.