U.S. patent number 3,860,161 [Application Number 05/328,640] was granted by the patent office on 1975-01-14 for cartridge tool with pocket arranged under the barrel.
This patent grant is currently assigned to Gunnebo Bruks Aktiebolag. Invention is credited to Erhard Rudolf Boye, Per Ingemar Engstrom.
United States Patent |
3,860,161 |
Engstrom , et al. |
January 14, 1975 |
CARTRIDGE TOOL WITH POCKET ARRANGED UNDER THE BARREL
Abstract
There is disclosed a gun for driving nails, bolts, etc., by the
force generated by detonating an explosive cartridge, the gun
including a firing mechanism with a striker pin for detonating the
cartridge by operating the firing mechanism. The gun comprises a
jacketed gun barrel including one or more recesses which are
connected with a pocket below the barrel so that the gases
generated upon firing of the gun can escape through said recesses
into the pocket and then an annular space outside the barrel and
inside of the jacket. Finally, the gases flow from the annular
space through one or more axial ducts to an exhaust opening at the
front end of the jacket.
Inventors: |
Engstrom; Per Ingemar
(Vastervik, SW), Boye; Erhard Rudolf (Gunnebobruk,
SW) |
Assignee: |
Gunnebo Bruks Aktiebolag
(Gunnebobruk, SW)
|
Family
ID: |
27555287 |
Appl.
No.: |
05/328,640 |
Filed: |
February 1, 1973 |
Foreign Application Priority Data
Current U.S.
Class: |
227/10 |
Current CPC
Class: |
F41C
3/06 (20130101); B25F 5/006 (20130101); B25C
1/143 (20130101); B25C 1/14 (20130101); F41A
21/10 (20130101); B25C 1/188 (20130101); B25C
1/105 (20130101) |
Current International
Class: |
B25F
5/00 (20060101); F41A 21/10 (20060101); F41C
3/00 (20060101); F41A 21/00 (20060101); B25C
1/14 (20060101); B25C 1/10 (20060101); B25C
1/00 (20060101); B25C 1/18 (20060101); F41C
3/06 (20060101); B25c 001/14 () |
Field of
Search: |
;227/10,11
;60/309,637 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Custer, Jr.; Granville Y.
Attorney, Agent or Firm: Hane, Baxley & Spiecens
Claims
We claim:
1. In a cartridge tool including a cartridge chamber for receiving
cartridges and communicating with a barrel which axially guides a
striker piston, the barrel being circumferentially surrounded by a
housing and extending beyond the end of the housing, the housing
being spaced from the barrel to define an annular region and being
fixed to a support member which includes the handle of the tool,
the improvement comprising, an opening in the barrel adjacent to
the cartridge chamber, a cyclonic type soot trap in the support
member having an entrance opening which communicates with the
opening in the barrel, the soot trap being configured with a
circular wall and a central post to induce vortex motion in gases
entering the entrance opening and the soot trap having an exit
opening which communicates with the region between the barrel and
the housing whereby the gases entering the soot trap are
constrained to circle one full time before exiting.
2. The cartridge tool of claim 1 wherein said soot trap is an open
cavity in said support member and has a cover removably supported
by said central post.
3. The cartridge tool of claim 2 further comprising a plurality of
axially extending ribs which are disposed circumferentially around
the annular region between the housing and the barrel to define a
plurality of passageways for introducing phase shifts in the sound
waves resulting from the firing of a cartridge as it exits the
front end of the housing.
4. The cartridge tool of claim 3 further comprising deflecting
means for directing the sound waves transversally outward as they
exit from said region.
Description
The present invention relates to a cartridge tool for nails and
bolts. With such tools, which use propellant cartridges containing
explosive charges, it is necessary to deflect the gases formed
after the firing in in such a way that the resulting noise is
reduced as much as possible. There is also a problem of eliminating
operation failures caused by soot particles in the exhaust gases.
An object of the present invention is to reduce such noise
substantially in comparison with that generated by cartridge tools
available in the market, as well as to remove soot particles in
such a way that these do not cause operational failures.
According to the invention the soot particles are removed by being
deflected immediately from the barrel to a chamber below the
barrel, where they are collected to be emptied out when a certain
quantity has been collected. The noise is reduced by conveying the
gases via the soot chamber to an annular region defined by the
outer surface of the barrel and the inner surface of a barrel
surrounding jacket. Within the annular region the exhaust gases are
given an axial movement in a forward direction, i.e., towards the
muzzle of the cartridge tool. At the front end the annular region
is divided up into a number of axial channels made by axial ribs
being arranged on one of the envelope surfaces of the space. The
channels are arranged so that phase shifts are introduced to reduce
the noise by means of sound wave cancellations. The channels emerge
at the front end of the jacket and are deflected radially by a
peripheral flange.
In the following, a complete cartridge tool embodying the present
invention will be described, with reference to the accompanying
drawings,
IN WHICH FIG. 1 shows a complete cartridge tool,
IN WHICH FIG. 2 shows where in the cartridge tool a cartridge case
ejector is arranged,
IN WHICH FIGS. 3 and 4 show two illustrations demonstrating the
cartridge case ejector in two different operating positions,
IN WHICH FIGS. 5 and 6 show a snap arrangement for fixing a nail
with guide washer in two different operating positions,
IN WHICH FIGS. 7, 8 and 9 show a muzzle part with the surrounding
sleeve of the cartridge tool,
IN WHICH FIGS. 10 and 11 show the front end of the cartridge
tool,
IN WHICH FIGS. 12 and 13 show a cartridge chamber with a cartridge
for the tool before and after the cartridge has been fired,
IN WHICH FIGS. 14 and 15 shows the trigger mechanism in two
different operating positions,
IN WHICH FIGS. 16 and 17 show the coaction between a guide pin
engaging a groove in the barrel of the cartridge tool and the
groove in two different relative positions,
IN WHICH FIGS. 18, 19 and 20 more completely show the coaction
between the pin according to FIGS. 16 and 17 and a striker piston
in three different relative positions, and
in which FIG. 21 shows how said pin is actuated transversally.
In FIGS. 1 and 2 of the reference designation 1 shows a tool body
section made of a single piece of metal. This part has a handle
part 2 and from the handle part there is a part 3 directed axially
forwards, at the top of which there is a guide part 4 with a more
or less cylindrical hole for guiding a barrel 68 to move axially
along the hole. To the right of the handle part 2 a housing 6 is
arranged for a trigger mechanism 7. The housing is provided with an
axial hole, which is coaxial with the hole in the part 4. The part
8 between the guide part 4 and the housing 6 has the character of a
cradle. A cross section of the cradle shows that it has a
semi-circular form and that the inner envelope surface of the
cradle forms a joining envelope surface between the inner envelope
surface of the guide part 4 and the inner envelope surface of the
housing 6. A cylindrical lining 9 is disposed within guide part 4
and housing 6. The lining 9 is cut away at the region 8 so that a
saddle or cradle-like lining is formed. At its front end the
cylinder lining has a radial flange 10, directed outwards (See FIG.
11). The rear end of the cylinder lining protrudes outside the
housing 6. The protruding part is provided with external threads
11. A casing 12 with internal threads 13 is screwed on to the
threads 11. The handle part 2, at its rear end, is provided with a
coherent member 14 which can be made of, for instance, some elastic
material, such as rubber or plastic. The member 14 also covers the
casing 12 and part of the outer surface of the housing 6. The
elastic material has the function of absorbing part of the recoil
force. In particular, it is made of elastic and resilient material
of considerable thickness so that the member 14 at the back of the
handle will be compressed by the recoil and absorb energy to
attenuate the recoil force. The coherent member 14, of elastic
material, is secured to the handle part 2 with the aid of a
threaded screw 15.
The firing mechanism consists of a cylindrical unit 16 having a
transverse hole 17. A bolt 18 is inserted in the hole 17. Disposed
between the inner end of the bolt and the bottom of the hole is a
spring 19. The bolt 18 has a transverse hole 20, in which is
inserted the front end of a striker pin member 21. At the top of
the hole there is a catch for the striker pin member 21 disengaged
when the bolt 18 moves rearwards. At its front end of the striker
pin member 21 has a striker pin 22. The left side of the hole 20 is
delimited by a wall 23, provided with a hole 24, of appropriate
size so that the striker pin 22 can be placed in the hole with a
small portion protruding beyond the left side of the wall 23. AT
its lower end the bolt 18 has a lug 25, which slides in an axial
groove 26 in the cylinder lining 9. In this way the cylindrical
unit 16, because of the lug 25 is constrained to move in the lining
9 only in the longitudinal direction of the groove 26 and between
its end positions. The cylindrical unit 16 has a part which is
recessed so that a transverse contact surface 27 is formed. The
recessed part 28 has the character of a cylinder. One end of a
helical spring 29 bears against the contact surface 27. The other
end of the spring bears against the transverse flange 30 of a
member which forms flange 30, and a tubular part 31. The tubular
part 31 has a contact surface 32. The tubular part 31 forms a
passage for the striker pin member 21, which at its rear end has a
flange 33, which can be brought to bear against contact surface 32.
The striker pin member 21 is provided with a spring 34 having one
end which bears against the left end of the striker pin member 21,
and another end which bears against the inner wall of the casing
12. The tubular part 31 is encircled by three rings 35, 36 and 37,
which bear against the transverse flange 30 and the bottom of the
casing 12. These three rings are of elastic material, and are
capable of absorbing recoil forces.
At the upper end of the handle 2, an axial, more or less
rectangular, through hole 38 is arranged. The hole 38 emerges into
a conventional trigger opening 39. The axial groove 26 emerges at
the upper part of the through hole 38. In the groove a two-armed
lever 41 is arranged, (see FIGS. 14 and 15), one end 40 of which
can move in the groove 26, so that a lug 42 arranged at the top of
end 40 can coact with the lug 25 of the bolt 18. The two-armed
lever 41 is arranged so that it can pivot around an axle 43, which
is arranged in the handle part 2. The other end 44 of the two-armed
lever 41, via an axel 45 has a two-armed arm 46 supported on it,
with one arm 47 directed more or less downwards and the other arm
48 which is more or less horizontal. The horizontal arm 48 is
aaranged in an axial groove 49 running through the two-armed lever
41. The arm 47 which is directed downwards has an oval groove 50.
Through the hole there is a pin 51. The pin is arranged in a
trigger 52. The trigger is movable axially in the through hole 38,
and has a more or less vertical hole 53 for the arm 47 which is
directed downwards. At its rear end the trigger 53 has a hole 54,
which extends more or less axially. One end of a helical spring 55
bears against the bottom of the hole 54 and the other end of the
spring bears against the bottom of a hole 56, arranged in the
coherent member 14. The helical spring causes the trigger to be
always in its front position, at the same time as the two-armed
lever 41 is caused to be in its lower position.
In the cylindrical unit, as will be noted from FIG. 2, a groove 57
has been cut down from the envelope surface. The groove has an
axial direction, so that an arm 58 can be placed in the groove 57.
From the ends of the arm 58, two arms 59 and 60 extend, as will be
noted from FIGS. 3 and 4. The last-mentioned two arms have a
transverse direction in relation to the arm 58 and are moreover
substantially directed towards the center axis of the cylindrical
unit 16. At its front end, the arm 60 is shaped into a claw 61,
intended to coact with a flange 62 of a cartridge case 63. At the
upper end of the arm 59 there is a cut-down section 64. Part of one
end of the helical spring 29 rests against cut-down section 64. The
arm 59 penetrates into a groove 65 made in the striker pin member
21. The arm 59 is made with a point 66, which point is in contact
with the front cross wall 67 of the groove 65, so that the helical
spring 29 will impart a moment directed forwards to the arm 58, so
that the point 61 can snap in, in front of the front side of the
flange 62.
A barrel 68 is arranged so that it can be displaced axially in the
cylindrical lining 9 (see FIG. 1). At its rear end the barrel has a
chamber 69, the front end of which emerges into a bore 70 of the
barrel. At its front end the barrel 68 has internal threads 71,
which coact with external threads 72 of a muzzle part 73, which has
a bore 74 with a diameter substantially corresponding to the head
100 of a nail 99. At its front end the muzzle part 73 has a
diameter junction, so that a bore 75 with a greater diameter is
obtained, i.e., a diameter corresponding to the diameter of a guide
washer 101 for the nail 99 (see FIGS. 5 and 6). In the bore 74 a
strike piston is arranged, which has a rear part 76 with a diameter
corresponding to the diameter 70 of the bore and a front part 77
which is always inserted in the bore 74, which part 77 has a
diameter corresponding to the bore 74. The barrel 68 has a through
axial groove 78 arranged in a vertical plane through the barrel 68.
In the groove a spring actuated lug 79 (see FIGS. 1 and 18) is
inserted, which limits the movement of the barrel 68 towards the
left so that the lug 79 in one position can be in contact with the
rear end and wall 80 of the groove 78. In this position the rear
end of the barrel 68 mainly coincides with the rear end of the
guide part 4. The lug 79 moreover is inserted so far into the bore
70 that it can be made to come into contact with the more or less
transversal bearing surface 81 of the rear part 76. In the front
end of the bore 74 and in front of the lug 79 a ring 82 of elastic
material is arranged, and in front of this and in contact with the
rear end of the ring there is a flange-like part 83 of a tubular
part 84. The tubular part 84 has a groove 85 for the lug 79. The
barrel 68 has a step 200 on its underneath side at the groove 78,
so that when the lug is completely inserted in the barrel 68 it can
move rearwards but not forwards (See FIG. 17).
In the part of the barrel 68 which is directed straight forward
under the groove 78 there is arranged axial groove 86, which
emerges into a pocket 87. Above the groove 86 the lining 9 is
provided with a through groove 86A, for which a number of through
holes can be substituted. The pocket 87 is intended to be covered
with a side cover or the like which, for instance, is fastened to
the pivot 88. The pocket is also shown in FIGS. 10 and 11. The
lining 9 has a peripheral bead 89, which has a more or less
rectangular cross section. Between the envelope surface of the
lining 9 and the guide part 4 to the left of the peripheral bead,
an annular space 90 is arranged, which is limited by the inner
envelope surface of the guide part 4. Around its outer envelope
surface the lining has longitudinally extending axial ribs 91,
originating from a point on the lining located between the ends 4
of the guide part. The axial ribs extend up to the front end of the
guide part 4. The upper sides of the axial ribs are in contact with
the inner envelope surface of the guide part 4. In this way the
lining in the guide part 4 obtains a number of axial channels
around its periphery in which the exhaust gases of the bolt gun are
distributed. As the flange 10 is at a certain distance from the
front end of the guide part 4, an exhaust opening 92 for said
channels is obtained. A space corresponding to the space 90 can be
arranged between the front edge of the ribs 91 and said exhaust
opening.
The muzzle part 73 has a relatively shallow peripheral recess 93,
as shown in FIGS. 5 and 6. In the left part of the muzzle part,
which is not recessed, there is an axial, shallow groove 94, which
extends to the left from the recess 93. In the front end of this
groove, i.e., at its left end, there is a radial hole 95, in which
a ball 96 is placed. The lower end of the hole is slightly
constricted, so that the ball cannot leave the hole 95 and become
lodged in the bore part 75. Around the muzzle part 73 and then at
the recess 93 a peripheral band 97 is placed. From one edge of the
band a tongue 98 extends to the left along the axial groove 94. The
tongue then covers the hole 95, so that the ball cannot be
dislodged upwards. The band 97 and the tongue 98 are of such
material that the tongue always strives to press the ball 96
downwards. The function of the ball 96 is to snap aside at the
insertion of a nail 99 with a nail head 100 and a guide washer 101
into the bores 74 and 75 which are arranged one after the other.
When the ball has snapped aside, the nail 99 is retained in the
bore. The advantage of this design compared with other designs is
that the recess in the front part of the muzzle part 73 will be
considerably smaller, which gives the front part greater strength.
When other designs are used for retaining the ball 96,
substantially greater recesses have hadd to be made. The
arrangement described for retaining the ball 96 can of course be
applied generally at muzzle parts for any arbitrary bolt guns
whatsoever.
The muzzle part 73 is encircled by a collar 102 consisting of a
front part 103 and a rear part 104, which is also shown in FIGS. 7
- 9. The rear end 104 is intended to have its edge in contact with
the flange 10. A certain portion of the front part of the muzzle
part 73 then protrudes out in front of the front edge of the part
103. In order to release the safety of the bolt gun, the front end
of the muzzle part must be pressed in to such an extent that its
front part coincides with the front edge of the part 103. On its
inner envelope surface the part 104 has two radial flanges 105 and
106, directed inwards. These flanges have two surfaces facing each
other, which are parallel with each other. A cross section through
the flanges gives an internal hole with two straight parallel sides
and two curved sides facing each other. On the muzzle part 73,
there is a disc-shaped part 107 which forms a peripheral raised
section in front of the external threads 72. The disc-shaped part
107 has four axial flat surfaces 108, 109, 110 and 111. The
surfaces 108 and 110 are at a distance from each other which mainly
corresponds to the distance between the inner edges of the flange
parts 105 and 106. The distance between the surfaces 109 and 111 is
the same. At the left end of the surfaces 111 and 109, two curved
flanges 112 and 113 are arranged, the curvature then approximately
corresponding to the internal diameter of the part 104. When the
muzzle part 73 is inserted into the collar 102, the flanges 112 and
113 must obtain the position shown in FIG. 8. When the flanges 112
and 113 have passed the flanges 105 and 106, and the disc-shaped
part 107 is to the left of the flanges 105 and 106 which are
directed downwards, they can be turned 90.degree.. Thereafter the
muzzle part 73 can be moved from contact through the flanges 112
and 113 against the flanges 105 and 106 to contact with the contact
surface 114. Due to the existence of the flanges 105 and 106 and
the surfaces 108 to 11 it is possible with the aid of the collar
102 to screw on the muzzle part 73 to the barrel 68. The collar 102
thus has three functions, viz. to serve as a cover, to serve as a
member which determines how far the barrel 68 should be moved
rearwards in order that the safety device of the bolt guns shall be
released, and to serve as a member with the aid of which the muzzle
part 73 can be unscrewed from or screwed on the barrel 68. The
collar cannot move the bolt gun or release the safety. In its
rearmost position of the collar leaves part of the front end of the
muzzle part 73 uncovered. However, this part is not sufficient to
provide a grip for a user. The collar 102 described can of course
have applications also on bolt guns of types other then the present
one.
At the rear end of the barrel 68 a cylindrical hole 115 is arranged
for the flange 62 of a cartridge 63 with a cylindrical main body
117 and a front more or less conical and folded part 118 (see FIGS.
12 and 13). The main body 117 is placed in a cylindrical hole 119
which has a diameter mainly corresponding to the diameter of the
cylindrical main body 117. The cylindrical hole 119 is followed to
the left by a conical hole 120 with an inner edge 116. The conical
hole 120 thereafter goes over into a hole 121 for transmission of
the powder gases developed from the cartridge when this has been
initiated. The taper of the conical hole and the length of the
cylindrical hole have been chosen in such a way that when the
cartridge has been initiated the front edge 122 of the conical hole
will function as a breaking edge, which involves that the folded
front part 118 will be transformed into a conical part 123 and a
tubular part 124. In this way, the front part of the cartridge will
not become jammed in the chamber, nor will any residue be deposited
in the chamber 69, which can make the chamber tighter and thereby
cause cartridges subsequently loaded to be jammed in the chamber.
At the chamber 69 the barrel 68 has an axial groove, which is
radial, so that the arm 60 can obtain the contact shown in FIG. 4.
The design described of the cartridge chamber is not limited for
use in the present type of bolt gun, but can have general
application.
The previously described triggered mechanism has been described to
a rather great extent, but not sufficiently, however, and
therefore, in the following, the trigger mechanism will be
described in more detail (see FIGS. 14 and 15). The horizontal arm
48 can move in an axial groove 49 in the two-armed lever 41 and its
free end can be caused to come into contact with the outer envelope
surface of the casing 9. The appearance of the groove will perhaps
best be noted from FIG. 2. The lug 25 for the bolt 18 has two
oblique surfaces, which are transversal, and have the reference
designation 125 and 126. The inclination of the surfaces is max.
80.degree.. In the longitudinal section the lug 25 has a dove-tail
character. The lug 42 has an oblique front side surface 127 with an
inclination of 80.degree., for coaction with the side surface 126
of the lug 25. The other end 44 of the lever 41 has an oblique
contact surface 128 for coaction with an oblique or chamfered
surface 129 in the upper left-hand side of the through hole 53.
When the trigger 52 is moved towards the left, the oblique contact
surface 128 is caused to slide along the chamfer 129, which
involves that the part 44 of he two-armed lever 41 obtains a
movement upwards, at the same time as the end 40 of the lever
obtains a movement downwards.
FIG. 16 shows the front part of the barrel 68 and also its axial
groove 78 and the inserted lug 79. The lug 79 has a more or less
rectangular cross section, and a width mainly corresponding to the
width of the groove. Outside the groove 78 the lug changes over
into a part 130 which cannot enter into the groove 78. The part 130
can appropriately be given a cylindrical form, and in the barrel 68
two recesses 131 and 132 have been made on either side of the
groove 78, and then in the outer envelope surface of the barrel.
The prupose of this is to achieve a guide groove for the part 130.
The part 130 thus fits in the groove formed by the recesses 131 and
132. At its left end the groove formed has an inclined cross wall
134, which involves that the part 130, when moving towards the
left, can slide upwards on the inclined wall 134 and can be caused
to come into direct contact with the outer envelope surface of the
barrel. The groove formed by the recesses 131 and 132 has a cross
wall 133 to the right, which is at right angles to the axis of the
barrel 68. This involves that when the part 130 moves to the right,
the part is caused to come into contact with the cross wall 133,
and has no possibility of sliding up on the envelope surface of the
barrel. The contact of the part 130 against the cross wall 133 will
be noted from FIG. 17. FIG. 18 shows how the part 130 is movably
arranged in the transversal direction in a lining 135, which is
arranged in part 3, in a hole. The lining 135 is screwed into a
hole in the tubular lining 9. At its bottom, the lining 135 has an
end wall 136. At the bottom, the part 130 changes over into a more
or less cylindrical journal formed part 137, which passes through a
hole 138 in the end wall 136. The journal formed part 137 has its
lower end supported in a transversal grip part 139, and then by
means of a shaft 140, which goes through the transversal grip part
139 and the journal formed part 137. The transversal grip part has
two grip surfaces 141 and 142, which will be located on either side
of the bolt gun, as shown in FIG. 1. The grip part 139 is in
contact with the outer side of the end wall 136. If one of the grip
surfaces 141 and 142, for instance the grip surface 142, is
actuated by a finger 143 (see FIG. 21) the part 130 will be caused
to move downwards so far that the part 130 will leave the groove
formed by the recesses 131 and 132, i.e., the barrel 68 has the
possibility of moving forwards until the lug 79 comes into contact
with the end wall 80 of the groove 78. At said actuation, the
portion of the grip part to the left of the shaft 140 will function
as a pivot for a lever formed by the grip part 139. The purpose of
the spring 144 is to return the part 130 to its original
position.
The ring of elastic material 82 and the tubular part 84 serve the
purpose of braking up the forwards movement of the striker bolt 77,
as the contact surface 81 comes into contact with the right end
edge of the tubular part 84 (see FIG. 20). The tubular part 84 also
serves the purpose of protecting the lug 79 from being destroyed
through the rear part 76. The parts 82 and 84 can be used generally
in bolt guns.
The bolt gun described above functions in the following way. It is
assumed that through a depression of the transverse grip part 139
the barrel has been able to move so far to the left that the lug 79
is in contact with the end wall 80. In this situation the striker
bolt 77 assumes its rear position in the bore 70. A cartridge 63 is
now inserted in the chamber 63. The barrel 68 is thereafter moved
towards the right end until the part 130 comes into contact with
the end wall 133, as is clearly shown in FIGS. 17 and 18. A nail 99
with a nail head 100 and with a guide washer 101 is inserted in the
bores 74 and 75. In order that the nail with guide washer shall
remain in place in the bores 74 and 75 the guide washer for the
nail must pass by a locking ball 96, which is actuated by a tongue
98, so that part of the ball penetrates into the bore 75. The
tongue 98 is spring actuated. When the nail is inserted in the
bores 74 and 75, the ball 96 is caused to snap aside, against the
spring actuation, when the guide washer passes by. When the guide
washer has passed, the ball again falls down and blocks the
movement of the guide washer towards the left. The nail is thereby
retained in the bore, and is ready to be fired. It should be
obvious that the nail can be inserted first and thereafter the
cartridge.
In the situation described the barrel assumes such a position that
the oblique surface 126 of the lug 25 is located in front of thhe
oblique surface 127 of the lug 42. Thus, firing cannot take place.
If the collar 104 has its rear end in contact with the flange 10,
the muzzle part 74 is protruding so far from the front end of the
collar as is required to position the lug 25 directly under the lug
42. If the front end of the muzzle part 73 is now pressed against
the surface into which a nail is to be driven, against the action
of the helical springs 29 and 34, the barrel 68 will move rearwards
so that the left end surface 103 of the collar 102 will be caused
to coincide with the left end surface of the muzzle part. The bolt
gun is now ready to be fired, i.e., the lug 42 is located directly
under the lug 25. When firing, the trigger 52 is moved to the
right, against the action of the spring 55. The journal 51 of the
trigger then moves the arm 47, so that the arm 47 pulls down the
left part 44 of the lever 41, causing the right-hand part 40 to
urge up the bolt 18 so far that the striker pin member 21 is
released for a movement towards the left, and the striker pin 22
passes through the hole 24 and sets off the cartridge 63. Due to
the lever system, very little force is required on the trigger 52
in order to move the bolt 18 which, for safety reasons, is actuated
by a very powerful spring. When the firing has taken place, the
spring 55 presses the trigger 52 towards the left. At this movement
the oblique contact surface 128 will slide along the chamfered
surface 129 causing the lever 41 to be turned clockwise, so that
the lug 42 ceases to coact with the lug 25. The trigger 52 with the
arms is now ready for a new firing. At the firing of the cartridge
63 the striker bolt 76 and its front part 77 will move towards the
left, to drive in the nail 99 with the part 77. At the movement of
the striker bolt towards the left, the bolt is caught up by the
contact surface 81 at the right end of the tubular part 84. Because
of the elastic ring 82, the bolt 76 is caught up gently. The
exhaust gases from the cartridge 63 pass through the groove 78 and
the groove 86A underneath in the lining 9 and the groove 86 in the
part 3 to the pocket 87, where the gases make have a vortex
movement downwards and thereafter pass up to the left of the
peripheral bead 89, after which they are given an axial direction
forwards in the space between the outer envelope surface of the
lining 9 and the inner envelope surface of the guide part 4. Owing
to the existence of the axial ribs, the gases are distributed out
into a number of channels, which emerge into the space 92 and
thereafter out into the open air. Due to the passage through the
channels, the gas is divided into separate jets which pass through
the channels formed by ribs 91 and are phase shifted in relation to
each other. When the gases pass through the pocket 87, the powder
residue is left in the pocket. This residue can be removed from the
bolt gun when the cover over the pocket is removed. By distributing
the gases to a number of channels, which are formed by the ribs, a
silencing effect is obtained. Both the residue collecting pocket
and the silencer can each be applied generally in bolt guns.
When the cartridge 63 is fired, a recoil occurs. Its effect is
dampened by the member 14, which is of elastic material. The recoil
is further dampened by the three rings 35, 36 and 37, which are of
elastic material.
When the nail has been driven in, the transversal grip part 139 is
given a downward movement through a finger 143 through actuation
downwards on either of the grip surfaces 141 or 142, and the
cylindrical part 130 is then caused to leave the groove formed by
the recesses 131 and 132. The barrel 68 can then be moved towards
the left, all the way to coming into contact with the end wall 80.
This movement of the barrel towards the left can be obtained either
by allowing the barrel to fall down of its own weight, or by giving
the barrel a centrifugal force. The barrel can also be pulled out.
At the movement of the barrel towards the left, the striker piston
is retained in a stationary position in the bolt gun due to the lug
79. This involves that during the movement of the barrel towards
the left a relative displacement between the striker piston and the
barrel takes place, so that the striker piston with its bolt will
be returned to its original position. When this has taken place,
the bolt gun is loaded anew with cartridge and nail, and the barrel
is returned to the position where the barrel and nail are ready for
driving a new nail.
As previously mentioned, the purpose of the collar 104 is to
protect the muzzle part 73 as well as to regulate the length of the
distance which the barrel must be pushed rearwards in order to
release the safety of the bolt gun. The muzzle part 73 is thus
movable in relation to the collar 102. The collar 102 has the
further property that it can be used for screwing in the muzzle
part 73 at the barrel 68. This is possible as soon as the
disc-formed part 107 with two opposite flat surfaces is in contact
with the corresponding surfaces 105 and 106 of the flanges.
When the barrel 68 with the cartridge 63 in the chamber 69 is moved
rearwards towards the cylindrical unit 16, the arm 60 will be moved
into an axial groove in the rear end of the barrel, so that the
claw 61 will snap out in front of the front side surface of the
flange 62. In this situation the flange is in contact with the
front cross surface of the cylindrical unit 16. When the barrel
then, at the actuation of the grip part 139, is given a movement
forwards, the cartridge 63 will be retained by the claw 61, and the
cartridge case will then fall out from the gun, or can be removed
by hand.
* * * * *