Slotting fastener driving device

This disclosure relates to a fastener driving device which produces a slot around a shank of the fastener as it is being driven. It is useful in a situation where a sheet material which is subject to expansion and contraction is to be fastened to a base and wherein movement resulting from expansion and contraction must be permitted to avoid buckling. The invention resides specifically in the guide body and driver element of the tool in that the driver element is T-shaped in cross section with the central portion of the T constituting the driver proper and the portions extending laterally from the central portion terminating below the bottom of the driver proper and having a recess extending from the bottom of the driver proper through the length of said punch into which the shank of a fastener may be pushed. In this way as the fastener is driven into the base through the sheet material, a slot is formed extending to both sides of the shank of the fastener.

BRIEF SUMMARY OF THE INVENTION 
While the invention is useful in any situation where a sheet of material, 
which expands and contracts with changes in temperature, must be fastened 
to a base while being permitted to move with respect to the base as it 
expands and contracts, the invention is particularly designed and will be 
described specifically in connection with the problem of fastening 
aluminum and vinyl siding to the studs of a building. The practice at the 
present time involves preslotting the siding at the factory. The slots, 
which are of course parallel to the length of the siding, are disposed at 
intervals which correspond to the spacing of the studs in the building to 
which the siding is to be attached. The nails or other fasteners are then 
driven through these slots and into the studs and the siding is then held 
in place but may move longitudinally as it expands and contracts. 
As a practical matter, however, the prepunched slots do not always line up 
with the studs. The installers in this situation will drive the fastener 
through non-slotted portions of the siding into the stud and then of 
course the siding is trapped against the stud and cannot move as it 
expands and contracts and the siding then buckles. This has been a very 
serious problem and there has been no sound solution to it. 
According to the present invention the siding is fastened to the studs by 
means of staples with one leg of the staple entering the stud directly 
beyond the edge of the siding and the other leg of the staple passing 
through a slot in the siding. The tool of the present invention is 
arranged to drive the staple and concurrently punch out a slot around the 
leg of the staple which passes through the siding. The tool is also 
designed so that the staple is not driven home tight against the siding 
whereby it would be trapped and as a result the siding is held in place 
securely but is completely free to move longitudinally as the material of 
the siding expands and contracts.

DETAILED DESCRIPTION 
FIGS. 1 and 2 show front and side elevational views of a conventional 
stapler or nailer generally operated pneumatically. The details of the 
mechanism for operating the stapler or nailer do not form a part of the 
present invention and will not be described in detail. 
Basically, the tool comprises a housing 10 within which there is a cylinder 
and a piston 11 which reciprocates therein. The tool has a handle portion 
12 by means of which it is gripped and a trigger mechanism for operating 
the tool. The trigger mechanism is not shown and a safety device 13 is 
only shown partially. A magazine for staples or nails is provided as at 14 
and the magazine communicates with a guide body 15, which embodies a guide 
track along which the driver 16 moves during the operation of stapling. 
The details of the tool will not be described further since the basic 
invention in the present case lies in the driver-punch element and the 
structure of the guide body. 
The driver may be best visualized as seen in the perspective view of FIG. 
12. The driver proper is shown at 20 and laterally extending portions 21 
give the driver-punch combination a T-shaped cross section. At the bottom 
end of the driver is the surface 22 which engages the crown of the staple 
in driving the staple into the work. The extending lateral portions 21 
terminate in a punch indicated generally at 23. The shape of the punch 
could be any of several commercially accepted and well known shapes 
including flat, pointed, concave, etc. The shape of the punch as described 
herein is that of an inverted V. The punch 23 is formed by the sloping 
portions 24 and it will be observed that between the apex 25 of the 
inverted V-shaped punch and the bottom 22 of the driver proper there is 
provided a recess 26 into which a leg of a staple may be pushed. The 
driver is, of course, provided with a hole 27 by means of which the driver 
is secured to the piston. It should also be noted that the portions 21 
which terminate in the punch are rounded as at 21a , so that the slot 
which is punched will terminate in rounded ends. 
In FIGS. 5 to 11 inclusive the action of the driver-punch combination in 
passing through the guide body and engaging in driving the staple is shown 
and for illustrative purposes the cover of the guide body has been 
removed. In these Figures, it is assumed that the piece of siding 30 has 
been placed upon the studs and that the siding has the upstanding flange 
31 along its upper edge, as is conventional. It will be noted that the 
nose of the guide body has the portion 32 raised above the portion 33 by 
the thickness of the siding 30, and that a notch 34 is provided of a 
greater depth than the height of the upstanding flange 31. The notch 34 
provides the abutment 35 against which the nose of the tool may be placed 
preparatory to driving the staple. The staple is indicated at 37 and it 
may be considered as the foremost staple in a stick of staples extending 
back into the magazine 14. 
It will also be noted that the guide body has the slanting portion 38, the 
purpose of which will appear as the description proceeds. 
Assuming now that the trigger of the tool has been actuated, the 
driver-punch combination begins to descend and the bottom 22 of the driver 
20 picks off the foremost staple in the stick, as shown in FIG. 6. 
In FIG. 7 the driver-punch combination has proceeded downward and the outer 
leg 37a of the staple 37 has begun to come into contact with the sloping 
portion 38 of the drive track. 
In FIG. 8 the staple has reached the point of entry into the siding 
material 30 and the base to which it is to be attached and it will be seen 
that the staple is in a somewhat slanted position. 
In FIG. 9 the driver continues to descend, the slanting portion 38 of the 
drive track pushes the upper portion of the leg 37b of the staple into the 
recess 26, so as to bring it into the apex 25 of the inverted V-shaped 
punch. In FIG. 10, the inverted V-shaped punch has begun to punch out a 
slot in the siding 30, and by virtue of the shift of the leg 37b of the 
staple 37 into the recess 26, the slot punched by the punch will extend to 
both sides of the staple leg 37b. 
In FIG. 11 the staple 37 is driven as far as it will be driven by the 
driver and it will be observed that the crown 37c of the staple is not 
driven down against the upstanding flange 31. Therefore, by virtue of the 
fact that the flange is not trapped by the staple and that the leg 37b 
passes through a slot, the siding 30 may move in a direction perpendicular 
to the drawing of FIG. 11 as it expands and contracts, thereby avoiding 
buckling. 
The depth to which the staple is driven is determined by the length of the 
driver proper in relation to the stroke of the piston and the location of 
the piston stop 11a. This determination is well known and within the 
capabilities of those skilled in the art. It is simply necessary to make 
the relationship between the piston and the piston stop and the length of 
the driver such that the crown of the staple in its fully driven condition 
does not bear against the upstanding flange 31. 
While the invention has been described in connection with a pneumatic 
stapler, it should be understood that the particular instrumentality for 
driving the driver-punch combination is not a limitation upon the present 
invention and that while the invention has been described specifically 
with staples and specifically in connection with the fastening of siding 
to studs, these likewise do not constitute limitations on the invention. 
It will be obvious that numerous modifications may be made without 
departing from the spirit of the invention and therefore no limitation not 
expressly set forth in the claims is intended and no such limitation 
should be implied.