U.S. patent number 3,918,619 [Application Number 05/427,309] was granted by the patent office on 1975-11-11 for safety device for seal fixing apparatus.
Invention is credited to Pierre Termet.
United States Patent |
3,918,619 |
Termet |
November 11, 1975 |
Safety device for seal fixing apparatus
Abstract
Fastening apparatus in the form of a gun in which the energy
resulting from the explosion of a cartridge drives a piston which
in turn drives the fastener, such as a nail, bolt or the like into
the material to be fastened. The barrel with its muzzle, cartridge
chamber, breech block, and firing device forms an assembly which
slides in a tubular casing rigidly attached to the stock of the
apparatus which carries the trigger, the assembly being urged by
means of a spring in the firing direction. The trigger is only able
to operate the firing device when the front end of the muzzle of
the barrel is protruding from the tubular casing by a length less
than a given length.
Inventors: |
Termet; Pierre (Lyon 3.degree.,
FR) |
Family
ID: |
9109272 |
Appl.
No.: |
05/427,309 |
Filed: |
December 21, 1973 |
Foreign Application Priority Data
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|
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Dec 26, 1972 [FR] |
|
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72.46212 |
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Current U.S.
Class: |
227/8;
227/10 |
Current CPC
Class: |
B25C
1/143 (20130101) |
Current International
Class: |
B25C
1/14 (20060101); B25C 1/00 (20060101); B25C
001/14 () |
Field of
Search: |
;227/8,10 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Custer, Jr.; Granville Y.
Attorney, Agent or Firm: Brisebois & Kruger
Claims
I claim:
1. Cartridge-actuated fastening device including:
a slidable assembly comprising a barrel, a muzzle at one end of
said barrel, a cartridge chamber at the other end of said barrel,
and a breech-block and percussion means for exploding said
cartridge located on the side of said chamber remote from said
barrel,
a driving piston slidably mounted in said barrel for actuation by
the gases produced by an explosion in said cartridge chamber to
eject a fastener from said muzzle and,
a tubular casing having a handle near one end thereof, said
assembly being mounted for axial sliding movement in said casing,
spring means biassing said assembly so that said muzzle projects
from the other end of said casing for a predetermined distance
except when said spring means is compressed by pressing said muzzle
against a material in which said fastener is to be driven,
latch means carried by said assembly and movable between a first
position in which said latch means does and a second position in
which it does not prevent operation of said percussion means,
a trigger mounted on said handle,
catch means carried by said trigger moving said latch means to said
second position when said catch means is in engagement with said
latch means and said trigger is actuated,
said latch means being spaced from a position in which it is
engaged by said catch means by a distance no greater than said
predetermined distance whenever said muzzle projects said
predetermined distance from said tubular member.
2. Device as claimed in claim 1 in which said catch means is in the
form of a fork and the latch means is a rod having a head beneath
which said fork engages to move said latch means when said trigger
is actuated with said muzzle pressed into said tubular member.
3. Device as claimed in claim 1 in which said muzzle has an
external peripheral chamfer at an angle of 60.degree. to the axis
of said nozzle.
4. Device as claimed in claim 1 in which said barrel carries
threads which engage correspondingly threaded means fixed to said
cartridge chamber and comprising a control member connected to
rotate said barrel relative to said threaded means and thereby
alter the axial position of said barrel relative to said cartridge
chamber to provide at least one gas vent between said barrel and
cartridge chamber.
5. Device as claimed in claim 4 in which said muzzle is slidably
mounted in said casing for movement toward and away from said
barrel and said muzzle and casing are provided with abutment means
which interengage to limit the sliding movement of said muzzle.
6. Device as claimed in claim 5 in which the abutment means on said
muzzle is brought closer to the abutment means on said casing as
said barrel is moved away from said cartridge chamber, thereby
decreasing the extent to which said muzzle is permitted to move
away from said barrel.
7. Device as claimed in claim 4 in which said control member is a
sleeve forming part of said casing and rotatable with respect to
the remainder of said casing, said sleeve encircling said barrel,
and said barrel and sleeve being provided with interfitting slot
and projecting means which cause said barrel to rotate with said
sleeve, while permitting relative axial sliding movement
therebetween.
Description
The present invention relates to a novel safety device for
fastener-driving apparatus of the type in which a fastener such as
a pin, a nail or a bolt is driven into suitable material by the
force produced by the explosion of a cartridge.
Such apparatus is already known in which the gases emanating from
the explosion of the cartridge propel the bolt by means of a
drive-piston which remains permanently inside the apparatus and
which is subjected on one side to the pressure resulting from the
explosion of the cartridge, while its other side bears against the
bolt to drive it into the material.
Such apparatus enables bolt driving velocities to be obtained which
are of the order of 60 to 180 metres/second, while apparatus known
as "direct firing" guns in which the gases emanating from the
explosion of the cartridge propels the bolt directly operate with
driving velocities of the order of 400 metres/second.
The so-called piston-driven apparatus is therefore much safer to
use than the so-called "direct firing" apparatus. It is for this
reason that in the majority of applications it is not necessary to
place a protective shield on the end of the barrel to protect the
user from possible ricochets of the bolt when it is fixed.
However, excessive inclination of the apparatus relative to the
perpendicular to the surface of the material into which the bolt is
being driven may cause ricochets even in the case of the
piston-driven apparatus. Although these ricochets (taking into
account the low initial velocity of this type of apparatus and of
the velocity reduction inherent in the penetration of the bolt into
the material) are of no great danger, it has appeared useful,
especially in the case of piston-driven apparatus having driving
velocities greater than approximately 100 metres/second, to provide
means whereby the said apparatus cannot fire the cartridge while
its axis makes an angle greater than a given angle, which is
15.degree. to 30.degree. for example, with the perpendicular to the
material to be penetrated.
The aim of the present invention is to permit construction of such
apparatus which cannot be fired while it is excessively inclined
relative to the position which it should occupy at the moment of
firing.
Another object of the invention is to provide a device of this type
in which the maximum angle at which the axis of the device may be
positioned with respect to a perpendicular to the material to be
penetrated without making it impossible to fire the device
decreases as the velocity with which the device is fired
increases.
These aims are attained by the present invention.
The object of the present invention is to provide a new article of
manufacture consisting of a fastener driver operating by means of
the energy resulting from the explosion of a cartridge, of the
piston-driven type, characterized by the fact that the assembly
formed by the barrel with its muzzle, the cartridge chamber, the
breech block and its firing device, slides in a tubular casing
forming an integral part of the stock of the apparatus which
carries the trigger, the above-mentioned assembly being resiliently
urged in the firing direction by the action of a spring, and the
trigger only being able to actuate the firing device when the front
end of the muzzle of the barrel is projecting from the tubular
casing by a length less than a given length.
In a particular embodiment of the invention, the trigger, which is
pivoted at a point adjacent to the rear portion of the apparatus,
has a fork-shaped part which, when the assembly including the
barrel is pushed backwards at the moment of firing, positions
itself around a lug provided with a head, so that the operation of
the trigger applies traction to this lug, which releases a
spring-biassed mass, with the result that this mass hits the
striker.
It will be observed that, in this embodiment, when the assembly
including the barrel is not pushed far enough backwards, the fork
cannot engage the lug so that operation of the trigger cannot cause
striking.
Under these conditions it is necessary to push the front end of the
gun into the tubular casing by a sufficient amount to be able to
fire.
As moreover this minimum insertion of the barrel corresponds to a
given angle of the axis of the apparatus relative to the surface of
the material to be penetrated which is such that said material
bears both on the outer edge of the front portion of the casing of
the apparatus and on the font end of the barrel, it will be
understood that the apparatus in accordance with the invention can
only fire when its inclination relative to the perpendicular to the
reception material is less than a given inclination.
In accordance with a particular embodiment of the invention, the
forward end of the muzzle of the barrel is formed with a chamfer so
that this forward portion of the muzzle of the barrel has a
flattened frusto-conical form (for example with an apex angle of
the order of 60.degree.).
In this way, the maximum angle of inclination is determined by the
contact with the surface of the material to be penetrated of the
apex of the truncated cone of the muzzle and of the outer edge of
the casing of the apparatus.
In accordance with a particular embodiment of the invention, the
fastening apparatus has a power adjustment device of the type in
which a portion of the gases emanating from the explosion are
vented through a gas-port of adjustable size, situated on the
periphery of the barrel adjacent to the cartridge explosion
chamber.
This embodiment of the invention is characterized by the fact that
the size of the above-mentioned gas-port is determined by the axial
displacement of the barrel and its muzzle relative to the assembly
forming the cartridge chamber, the breech and the striking
device.
As a result, in the limit position of the breech relative to the
stock of the apparatus which carries the trigger, (the said
position permitting firing), the distance by which the muzzle of
the barrel projects from the tubular casing which surrounds is
proportional to the section of the gas port which is open and
consequently to the bolt driving capacity.
Consequently the maximum angle of inclination which the apparatus
may assume with respect to a perpendicular to the surface of the
material to be penetrated, and still be fired, decreases as the
speed at which the bolt is projected increases.
In this way, the maximum angle with the perpendicular to the
material may be varied on firing as a function of the driving
velocity, it being understood that in accordance with experience
and the regulations laid down up to the present time, it is not
necessary to impose a particular firing angle in the case in which
the bolt is driven with a velocity of less than 100
metres/second.
It will be seen that, in a particularly simple and efficient
manner, the invention enables the risk of ricochets which may occur
in apparatus of the piston-driven type for velocities of the order
of 100 to 180 metres/seconds to be avoided, since the gun may be
fired only when at an angle as close to the position perpendicular
to the material to be penetrated which is dependent on the
penetration velocity.
However, in a modification of this particular embodiment, while the
muzzle of the device cooperates with the barrel to guide the
projectile, the muzzle is axially movable with respect to the
barrel, and the maximum depression of the muzzle is determined by
the abutment of the muzzle against a member located radially
outward of the barrel and fixed to the member defining the
cartridge chamber.
Under these circumstances, the axial displacement of the barrel
relative to the cartridge chamber, which determines the size of the
gas-port, either does not affect the muzzle during any part of the
displacement of the barrel, thus maintaining constant the maximum
angle of inclination of the apparatus, or in a modification,
affects it only during a portion of this adjustment stroke, so that
the limit angle is fixed for the highest firing velocities and then
increases when the lower velocities are reached, due to adjustment
of the gas-port.
Furthermore it is possible, whether the muzzle is axially connected
to the barrel or whether it is axially independent of the barrel,
to render the muzzle independent of the barrel for rotation when
axial displacement of the barrel is effected under the influence of
its own rotation caused by an adjustment ring.
In order to provide a better understanding of the invention, an
embodiment taken as an example and illustrated in the drawings will
now be described purely by way of illustration and example.
In these drawings:
FIG. 1 is a diagrammatic axial sectional view of a fastener driver
in accordance with the invention;
FIg. 2 is a view corresponding to FIG. 1, showing the apparatus
being applied to a material to be penetrated while being inclined
at the maximum angle for which firing is possible, the power being
adjusted to the maximum;
FIGS. 3 and 4 are two detail views taken along the line III--III of
FIG. 2, illustrating the case in which striking is possible and the
case in which striking is not possible respectively;
FIG. 5 is a view corresponding to FIG. 2 illustrating the case in
which the apparatus is adjusted to fire at a lower velocity;
and
FIG. 6 is an axial section of the apparatus in accordance with a
modification of the invention.
The apparatus which is shown in the drawings is of the type in
which it is possible to adjust the power, i.e. to use an explosive
charge of uniform power to perform jobs requiring different energy
values.
FIG. 1 shows the drive-piston 1 which propels a bolt 2 with a
threaded head as it slides in the bore 3 of a barrel 4 which is
provided with a muzzle 5 able to move axially relative to barrel 4
at the moment when shoulder 1a of drive-piston 1 impinges against
shoulder 5a of the mobile muzzle.
This apparatus is known in prior art and will not be described here
in more detail.
The barrel 4 is screwed by means of threads 6 into a sleeve 7
rigidly attached to the member 8 defining the peripheral wall of a
cartridge chamber.
A breech block 9 having a firing pin 10 closes the rear end of
cartridge chamber 8 which contains cartridge 11.
The assembly just described is surrounded by a cylindrical casing,
forming the body of the apparatus and supporting trigger 12.
This casing consists of a rear member 13 including the grip 14 and
surrounding the striking device.
The member 13 is connected in a known manner to cylindrical members
15, 16 and 17 which constitute the tubular casing of the barrel up
to adjacent the front end of the gun.
The member 17 may be manually rotated relative to the grip 14, and
this causes rotation of the barrel 4 due to engagement of the screw
4a, which projects from the barrel, in the longitudinal slot 17b
formed in the member 17. As the barrel 4 is rotated it screws or
unscrews relative to sleeve 7 by means of thread 6 moves the member
18, which is rigidly attached to barrel 4, nearer to or farther
from cartridge chamber 8.
A gas-port of smaller or larger size is thus formed between the
member 8 and 18 which, in known manner, enables the exhaust gases
resulting from the explosion of the cartridge to be evacuated from
the apparatus.
In the position shown in FIG. 1, the members 8 and 18 are in
contact so that the gas-port has a zero section which corresponds
to a maximum driving velocity.
Inside member 13 constituting the stock of the apparatus is a
mobile mass 19 subjected to the action of a spring 20 which is
retained in the position shown in FIG. 1 by pin 21 which is urged
upwards by the trigger 12, which is biassed upwardly by the trigger
spring 12a.
Pin 21 is rigidly attached to a lug 22 provided with a head which
can move towards trigger 12 which is pivoted at 23 at the back of
the apparatus.
Trigger 12 has a fork-shaped part 24 which, when the barrel of the
apparatus is pushed backwards, engages the head of lug 22.
It will be understood that under these circumstances, when the
trigger is operated, pin 21 moves downwardly and releases mass 19
which, under the influence of the spring, hits the member 25 which
operates the percussion pin 10.
To permit backward movement of the barrel inside the stock of the
apparatus against the action of spring 20', it is also necessary to
move the member 26 downwardly, so that an orifice 26a in the member
26 comes into alignment with the pin 27 which is rigidly attached
to the barrel, so that the pin 27 may enter the orifice. This
constitutes a safety catch of a type already known.
It will also be noticed in FIG. 1 that the forward end of muzzle 5
has a frusto-conical surface 5b having an apex angle relative to
the axis of approximately 60.degree..
The operation of the apparatus is relatively simple. The
cylindrical member 16, is fixed to the sleeve 7, by the screw 16a.
AS hereinbefore pointed out, this sleeve is fixed to the member 8
defining the cartridge chamber so that the members 16, 7 and 8
rotate as a unit. The member 8 therefore may be unscrewed from the
member 9, by simply rotating the sleeve 16. A cartridge may then be
inserted into the cartridge chamber, and a bolt dropped into the
muzzle of the gun. After introduction of a cartridge and a bolt
into the apparatus, all that is necessary is to apply the end of
muzzle 5 of the barrel against the surface of the material into
which it is required to drive the bolt and to apply a force towards
this material by bearing on grip 14. If the safety member 26 is
pressed simultaneously, it is possible to move the stock of the
apparatus towards the material into which it is required to drive
the bolt. As this is done, fork 24 embraces the lug having the head
22, which permits firing by squeezing trigger 12.
FIG. 2 shows the fastening apparatus of FIG. 1 placed against a
material 28 which is to be penetrated, the axis of the barrel being
inclined relative to the perpendicular to the surface of this
material 28, by the maximum angle compatible with firing.
In this position, the assembly formed by barrel 4 with its muzzle
5, cartridge chamber 8 and breech 9 is pushed backwards against the
action of spring 20', safety member 26 being withdrawn into the
stock 13 of the apparatus. Mass 19 bears against pin 21, while
spring 20 is compressed.
At the front of the apparatus, the peripheral edge 17a of
cylindrical member 17 bears against reception material 28, as does
the edge of smaller diameter 5c of frusto-conical surface 5b of
muzzle 5.
It will be noted that because of the frusto-conical chamfer 5b, the
apparatus can bear on thet surface of material 28 at two points 5c
and 17a, which are situated at a not negligeable distance from each
other, thus permitting determination with good precision of the
maximum firing angle for a projection of a given distancce of the
muzzle of the barrel 5 from sleeve 17.
In the position shown in FIG. 2, fork 24 rigidly attached to the
trigger engages the lug 22 just sufficiently to permit firing. This
position corresponds to the maximum angle at which firing remains
possible.
FIGS. 3 and 4 show diagrammatically views along the line III--III
of FIG. 2. Each of these views again shows fork 24 and the lug
22.
In the case of FIG. 3, fork 24 completely engages the lug 22 so as
to allow firing, the pistol being in a normal firing position, with
its axis substantially perpendicular to the surface of material
28.
On the other hand, in the case of FIG. 4, fork 24 is not in
engagement with lug 22, either because the apparatus is not applied
against the material to be penetrated, or because the apparatus is
forming an angle with the perpendicular to material 28 which is
incompatible with the possibility of firing.
The respective positions of fork 24 and lug 22 are in the case of
FIG. 1 intermediate between the positions of FIG. 3 and FIG. 4,
with the end of fork 24 only just engaging lug 22.
In the case of FIG. 5, the apparatus has been adjusted to fire with
a reduced power.
For this barrel 4 and its muzzle 5 have been rotated relative to
sleeve 7 rigidly attached to cartridge chamber 8, which rotation
has moved the barrel by means of thread 6 in the firing direction,
creating a circular gas-port 29 for evacuation of a portion of the
gases emanating from the explosion of the cartridge 11.
An outward displacement of muzzle 5 of the barrel has thus been
produced, the members supported by cartridge chamber 8 and breech 9
having remained in the same positions relative to stock 13 of the
apparatus.
As a result, in the position shown in FIG. 5, fork 24 rigidly
attached to trigger 12 is in the limit position in which it can
engage the lug 22.
It will be observed that in accordance with the invention, the
distance by which muzzle 5 of the barrel projects from member 17
corresponds to the extent to which circular gas-port 29 is
opened.
Consequently the apparatus in accordance with the invention permits
firing with the axis of the barrel further removed from the
perpendicular to material 28 when the power and consequently the
driving speed of the projectile are reduced.
At 30 in FIG. 5 is shown the position of the firing axis most
distant from the perpendicular to material 28 for the maximum power
of the apparatus (FIG. 2) and at 31 is shown the corresponding
position of the firing axis of the apparatus in accordance with
FIG. 5.
It is quite clear that power adjustment requires the apparatus to
fire with its axis closer to the perpendicular to the surface 28
when the driving velocity of the projectile is higher.
It arises from the explanations given above with reference to the
drawings that the invention enables a safety device to be formed in
a particularly simple and efficient manner for piston-driven
apparatus which does not require the use of a shield arranged at
the end of the barrel.
Reference is now made to FIG. 6 in which the corresponding parts
have received the same references as in FIG. 1.
In contrast to the preceding apparatus, the apparatus shown in FIG.
6 has a muzzle 33 which is, even when in its position of maximum
depression, axially separated from the barrel 32. In its front
portion barrel 32 has a dog 34 co-operating with four arms 35 of a
counter-dog rigidly attached to muzzle 33. Of course central bore 3
is continued inside dog 34 which, like arms 35, is not shown in
axial section in the figure. Dog 34 also has a circular groove
which receives the end of a screw 36 screwed through barrel 32. In
this way dog 34 is axially immovable with respect to barrel 32 by
the groove and screw, but capable of rotation relative to this
barrel, so that the rotation of barrel 32 will not be transmitted
to muzzle 33.
It will therefore be understood that the dog device 34, 35 is
simply provided to ensure continuity of bore 3, while disconnecting
barrel 32 from muzzle 33 both axially and in rotation.
On its outer periphery muzzle 33 has a longitudinal groove 37 which
cooperates with a lug 38 projecting inwardly from the front
cylindrical part 39 of the casing so that muzzle 33 and part 39
will rotate together. In its front end the part 39 has a double
notch 40 in the same vertical plane as a notch 41 in the front edge
of muzzle 33. These notches are designed to receive complementary
parts carried by the projectiles so as to prevent rotation of the
projectile.
The member 8 defining the peripheral wall of the cartridge chamber
carries a generally cylindrical extension 42 which has internal
threads 6 co-operating with a corresponding threads on barrel 32.
The extension 42 is surrounded by an externally threaded ring 43 on
the left end of which is screwed a ring 44 forming part of the
casing and having a longitudinal slot 45 through which passes the
head of a screw 46 screwed into the extension 42 so that ring 44
and ring 43 cannot rotate. on the right edge of ring 43 is screwed
an annular nut 47 which by means of an interior groove axially
retains a cylindrical member 48 having an extension 39, which can
turn relative to the member 48 in ball-bearings 49 housed in
suitable grooves.
The member 48 has a longitudinal slot 50 in which screw 36 is
slidable.
it will also be observed that an annular member 51 is inserted
between the right end of extension 42 and muzzle 33, and rigidly
attached to muzzle 33 for rotation therewith.
This member 51 is in contact with a ring 52 having a slot for the
passage of screw 36.
It will be understood that members 43, 44, 47, 48 and 39 form the
casing generally referenced 13 end it will be observed that the
total length of this casing may be adjusted by screwing ring 43
more or less into ring 44 and that furthermore member 48 can rotate
relative to members 43, 47 and 39 but is not axially slidable
relative thereto.
On ring 43 may be placed a short ring 52 bearing an adjustment
marker adapted to be locked in place by a nut 53 screwed onto ring
43. This marker cooperates with graduation lines carried by the
outer visible face of the member 48.
In the position shown in the drawing barrel 32, screwed completely
onto threads 6, has its end against the cartridge chamber 8 so that
the gas-port is closed. When, in the position shown in the drawing,
thrust is applied to the end 41 of muzzle 33 which tends to cause
the muzzle to enter the casing, this thrust is transmitted by
member 51 and 52 to member 42 and from there to cartridge chamber 8
and to the whole firing mechanism so that this assembly slides
inwards, carrying with it barrel 32. It will be seen that, in this
position, an axial clearance 55, of the order of 2 mm, for example,
exists inside dog 34.
When it is required to reduce the firing velocity, the operator
turns the graduated member 48 manually. In doing this, through
screw 36, he turns barrel 32 in thread 6 so that the barrel moves
axially away from the member 8, thus forming a gas-port reducing
the thrust of the gases on piston 1 upon firing. In this motion of
barrel 32 to the right, the dog is driven axially to the right but
is free to rotate because of the groove which receives screw 36. It
is therefore possible to rotationally position muzzle 33 in any
suitable manner, whatever may be the position of the barrel.
Moreover, because of the clearance 55, it will be observed that the
displacement of barrel 32 to the right does not modify the axial
position of muzzle 33, at least while a clearance remains in the
dog. As a result, for small gas-port openings with clearance 55
still present, muzzle 33 retains its axial position and the maximum
angle of inclination permitting firing remains constant.
On the other hand, if a very large gas port is formed by moving
barrel 32 a large amount to the right, greater than 2 mm for
example, clearance 5 is finally eliminated and from this moment the
subsequent displacement of the barrel under the effect of the
rotation of the gas-port adjustment member 48, causes the
corresponding displacement of muzzle 33, so that from this moment
the angle of inclination is increased as was seen with regard to
the preceding apparatus.
It is self-evident that if a sufficiently large clearance 55 is
provided to start with, it is possible to obtain an apparatus
having a limited firing angle which remains constant through the
whole range of adjustment of the gas-port and consequently of the
firing velocity.
It will be understood that the embodiment given above is given
purely by way of example and any desirable modification may be made
to it without thereby departing from the scope of the
invention.
In particular it is obvious that the trigger apparatus which
controls the firing may be of a different type, the only condition
being that it is automatically rendered inoperative as soon as the
apparatus is inclined by a given angle relative to the
perpendicular to the material to be penetrated.
* * * * *