US3543986A

US3543986A - Extractor for cartridge-actuated device

Info

Publication number: US3543986A
Application number: US773850A
Authority: US
Inventors: Andrew G Bakoledis; James B Brosious
Original assignee: Olin Corp
Current assignee: Illinois Tool Works Inc
Priority date: 1968-11-06
Filing date: 1968-11-06
Publication date: 1970-12-01
Anticipated expiration: 1987-12-01
Also published as: ZA696002B; CH507782A; GB1262533A; DE1953224A1; FR2022706A1

Description

United States Patent Andrew G. Bakoledis Clinton;

James B. Brosious, Cheshire, Connecticut 773,850

Nov. 6, 1968 Dec. 1, i970 Olin Corporation a corporation of Virginia inventors Appl. No. Filed Patented Assignee EXTRACTOR FOR CARTRlDGE-ACTUATED DEVICE 7 Claims, 8 Drawing Figs.

US. Cl 227/10 rm. Cl BZSc 1 14 Field ol'Search 227/8, 9, 10, l l

[56] References Cited UNITED STATES PATENTS 2,957,176 l0/l960 Henning et al 227/ 8 3,066,302 12/1962 DeCaro et al... 227/10 3,341,101 9/l967 Butleretal. 227/10X Primary Examiner-Granville Y. Custer, Jr.

Attorneysli, Samuel Kieser, William W. Jones, Richard S.

Strickier, Robert H. Bachman, Donald R. Motsko and Thomas P. ODay ABSTRACT: An extractor for a cartridge-actuated tool which is mounted on the cocking rod and is resilient to allow the edge portion thereof to cam over the rim of a cartridge and snap firmly against the cartridge case. The extractor is also resiliently twistable so that the edge portion digs into the cartridge case and causes the cartridge to fly free of the chamber to assure full extraction.

I ATTORNEY JAMES B. BROS/OUS Sheet Patented Dec. 1, 1970 EXTRACTOR FOR CARTRIDGE-ACTUATED DEVICE This invention relates generally to power actuated tools for driving fasteners or other members into masonry, concrete, wood, steel, or the like. More particularly, this invention relates to a cartridge extractor for use in tools of this type.

One type of extractor that is commonly used in power actuated tools of the above type is the claw type extractor. This type includes an extractor member which is pivotally mounted to the housing so that when the cartridge chamber is moved rearwardly in the tool, the inclined forward face of the claw of the extractor will cam over the cartridge case head as the extractor moves from its laterally inward position to its outward position. After the firing operation, when the barrel member is moved forward relative to the housing, the claw of the extractor engages the head of the cartridge on one side thereof and pulls the cartridge relatively rearwardly causing the cartridge to twist and be ejected through an ejection port. One disadvantage with this type of extractor is that when the cartridge is actuated and the crimp blown open, the sidewall of the cartridge expands under the gas pressure. In some cases, the fit between the outer sidewall and cartridge chamber of the fired cartridge is so tight that the extractor claw will tend to ride up and over the shoulder of the head portion of the cartridge rather than properly ejecting the cartridge. In this event, the cartridge will have to be ejected by applying a suitable rod member through the muzzle end .of the tool into engagement with the fired cartridge shell and knocking it out by repeated blows upon a rod member.

In the case of some tools which utilize the piston member for driving the fastener, the extractor comprises a rearward extension on the piston member. As the barrel member is moved from its closed to open position, and the piston member returned to its firing position adjacent the breech of the barrel member, the projection on the end of the piston will loosen the cartridge shell from the cartridge chamber and the compressed air built up during the relative movement of the piston and barrel will cause ejection of the cartridge shell. However, in some cases, especially when the piston is returned to its firing position slowly, the amount of compressed air between the rearward face of the piston and the cartridge will not be sufficient to properly eject the cartridge shell.

Accordingly, it is an object of the present invention to provide an extractor for a power actuated fastening tool which overcomes the above-mentioned difficulties.

More particularly, it is an object of this invention to provide an extractor which tends to bite into rather than slip over the head of the cartridge during the extraction stroke.

Further, it is an object ofthe present invention to provide an extractor which is inexpensive to manufacture and easy to install.

A still further object of this invention is to provide an extractor which tends to be resilient in a direction generally axial of the tool so that a spring force is applied to the cartridge to aid in the extraction operation.

These and other objects of the invention will become more apparent by reference to the following description of a preferred embodiment of the invention and to the drawings in which:

FIG. 1 is a top plan view, having a portion partially broken away, of a power actuated tool incorporating the improvements of this invention;

FIG. 2 is a vertical sectional view taken along the lines 2-2 of FIG. 1;

FIG. 3 is a transverse sectional view taken along the lines 3-3 of FIG. 2;

FIG. 4 is a transverse sectional view taken along the lines 4-4 of FIG. 2;

FIG. 5 is a vertical sectional view similar to FIG. 2, but showing the components of the tool in the cocked position;

FIG. 6 is a sectional view taken along the lines 6-6 of FIG. 4;

FIG. 7 is a view similar to FIG. 6, but showing the barrel member in its rearward position whereupon the tool is in the cocked position as shown in FIG. 5, but after the cartridge has been fired, with the extractor shown in its cartridge engaging position; and

FIG. 8 is a view similar to FIG. 4, but showing the barrel member as it is moved forward relative to the housing and the cartridge member about to be extracted.

Referring to the drawings, and in particular FIGS. I and 2, a tool constructed in accordance with the present invention includes a housing 2 having a tubular forward portion 4 and a rearward portion 6. The tubular forward portion 4 includes an elongated opening 8 to provide access for loading and ejecting an explosive cartridge. The rearward portion 6 of the housing 2 houses the firing mechanism 10 and also includes a pistol grip 12 and trigger guard 14.

A barrel assembly 16 is mounted within the forward tubular portion 4 of the housing 2 and extends from the muzzle end thereof. The barrelassembly 16 includes a barrel member 18 having a bore 20 therein. The barrel member 18 includes a cartridge receiving chamber 22 at its breech end for the reception of an explosive cartridge 24. The cartridge receiving chamber 22 includes a counterbore 26 against which the forward face 28 of the shoulder 29 of the cartridge 24 is pressed when the tool is in the firing position. The bottom outside surface of the barrel member 18 includes an axially extending bottom portion 30 which is planar in a horizontal direction. An elongated slot 32 extends through the bottom portion 30. The barrel assembly 16 is restrained during its reciprocal movement within the tubular portion 4 ofthe housing 2 by virtue ofa pin member 34 which is threadedly secured to the forward end of the tubular portion 4 of the housing 2 and extends through the slot 32 in the barrel member 18 into the interior thereof.

The barrel assembly 16 also includes a muzzle bushing 36 which has a bore 38 oflesser diameter than the bore 20 in the barrel member 18 and is threadedly attached to the forward end thereof. A sleeve member 40 surrounds the muzzle end of the barrel member 18 and includes an inturned flange 42' which is positioned between the forward edge 44 of the barrel member 18 and a shoulder 46 on the external surface of the muzzle bushing 36.

A piston member 48 may be mounted for reciprocal movement within the barrel assembly 16. The piston member 48 includes a generally cylindrical head portion 50 and a reduced, elongated, cylindrical shank portion 52 extending forwardly therefrom. A piston ring 54 may be mounted within a suitable groove 56 extending circumferentially about the head portion 50 of the piston member 48.

The muzzle bushing 36 is provided with a counterbore 58 in its rearward surface. A suitable buffer member 60 may be mounted in the counterbore 58 to absorb the energy of the piston member 48 in the event that the piston member 48 is overdriven. In the preferred embodiment, the buffer member 60 comprises a hollow, cylindrical element fabricated from a suitable material such as polyurethane, nylon, or other suitable elastomeric material. The interior diameter of the buffer member 60 must be at least as great as the diameter of the bore 38 in the muzzle bushing 36, which in turn is of such a size as to slidably receive the shank portion 52 of the piston member 48. The buffer member 60 extends rearwardly in the tool to a point axially rearward of the rearward face of the muzzle bushing 36.

The forward and rearward portions 4 and 6, respectively, of the housing 2 are separated by a breech face 62 which has a frustoconical opening 64 therein. The firing mechanism 10 includes a firing pin 66 which is mounted behind the breech face 62 for axial movement in the housing 2 and includes a frustoconical forward nose portion 68 and intermediate body portion 70. The firing pin 66 is urged forwardly by a suitable firing pin spring member 72. The body portion 70 is provided with a transversely extending opening 74 as shown in FIG. 5 in which is mounted a detent member 76 which extends downwardly from the body portion70. The detent member 76 is spring biased outwardly away from the axis of the firing pin 66 by suitable spring means 78. A cocking rod 80 is mounted for reciprocation in a groove 82 in the rearward portion 6 of the housing 2 and includes a forward portion 84 which extends through the breech face 62 and into the tubular forward portion 4 of the housing 2. The cocking rod 80 may be spring biased into its forward position by a suitable spring member 86. The cocking rod 80 also includes an elongated opening 88 through which the detent member 76 on the firing pin 66 normally extends. The cocking rod is generally channel-shaped with a web 92 and two sidewalls 94 and 96, respectively.

A trigger member 98 having a scar portion 100 may be pivotally mounted above the trigger guard 14 by a pivot pin 102. The trigger is resiliently urged away from the firing position by a suitable spring member 104.

An extractor member 106 is attached to and preferably integral with the cocking rod 80 adjacent the forward end thereof. As shown particularly in FIGS. 1 to 3, the extractor member includes a first portion 108 extending outwardly from the web of the cocking rod 80 in an upwardly direction. A second portion 110 is generally flat and is connected to the first portion by an arcuate portion 112. The second portion 110 extends generally upwardly and inwardly and terminates in a sharp edge portion 114.

The breech end of the barrel member 18 is provided with a tapering groove 116 which has a midplane coincident with the midplane of the second portion of the extractor 106. The width of the tapering groove 116 should be greater than the thickness of the extractor member 106 to provide room for limited movement for the reasons to be set forth below. As can be seen in FIGS. 68, the groove 116 extends from a point in front ofthe shoulder 118 formed by the counterbore 26in the cartridge receiving chamber 22 forwardly at a preferred angle of about 30 from the axis of the barrel member. The end of the extractor 106 is tapered to provide a cam surface 107 as shown also in FIGS. 6 to 8. This taper is at an angle slightly greater than the angle between the axis of the barrel member and the bottom of the groove 116. In addition, as viewed in FIG. 6, the terminal edge of the extractor normally extends inwardly toward the axis of the cartridge receiving chamber 22 beyond the wall thereof for the purpose to be explained below.

In operation, the barrel assembly 16 is moved forward relative to the housing 2 from the position shown in FIG. 2 whereby the pin member 34 will engage the forward face of the head portion 50 of the piston member 48, so that the piston member 48 will remain stationary with the housing 2 as the barrel assembly 16 is moved forwardly relative thereto until the breech ofthe barrel member 18 engages the rearward face of the head portion 50 of the piston member 48. With the piston member 48 in its rearward position within the barrel member 18, a fastener may be positioned within the muzzle bushing 36 and a cartridge member 24 positioned in the cartridge receiving chamber 22.

To fire the tool, the operator must position the forward end of the muzzle bushing 36 against a suitable work surface and push on the housing 2 to move the housing 2 forward relative to the barrel. In so doing, the cocking rod 80 abuts the rearward face of the barrel member 18 so that the housing 2 moves forward relative thereto. By virtue of the detent member 76 extending into the opening 88 of the cocking rod 80, the housing 2 also moves forwardly with respect to the firing pin 66, depressing the firing pin spring member 72, until the breech face 62 abuts the rearward surface of the barrel member 18. At this point, the detent member 76 will have been moved into operable alinement with the sear portion 100 of the trigger member 98 so that by pulling the trigger member 98, the sear portion 100 will engage the detent member 76 and depress it radially inwardly until it clears the cocking rod 80 whereupon the firing pin 66 will be propelled forward under the action of the firing pin spring member 72 until the nose portion 68 thereof projects through the frustoconical opening 64 in the breech face 62 and actuates the cartridge 24-. The gases generated by the explosion of the cartridge 24 will drive the piston member 48 forwardly, thereby driving the fastener into the work surface. Reference may be made to U.S. Pat. No. 3,172,118 concerning this phase of the operation-of the tool.

Simultaneously with the cocking operation, as the housing 2 is pushed forward relative to the barrel assembly 16, the extractor member 106 is moved into the groove 116 in the rearward face of the barrel member 18. As described above, the sharp edge portion 114 of the extractor member 106 extends toward the axis of the barrel a distance such that in its normal position as shown in FIG. 5, it is spaced closer thereto than the inner edge of the cartridge receiving chamber 22. Accordingly, as the extractor member 106 moves into the groove 116, the edge of the shoulder 29 of the cartridge 24 will be engaged by the cam surface 107 of the extractor member 106 whereby the extractor member will flex outwardly, away from the axis of the tool, until the sharp edge portion 114 rides over the shoulder 29 of the cartridge and the extractor member 106 moves inwardly due to its resilience into engagement with the cartridge at a point forward of the shoulder 29. Due to the fact that the normal position of the end of the extractor is inwardly from the edge of the cartridge 24, there is a spring force tend ing to urge the edge portion 114 into the cartridge casing. When the barrel assembly 16 is moved forwardly after the firing operation, and the cocking rod moves into its forwardmost position, the extractor member 106 will exert a force on the shoulder 29 of the spent cartridge tending to pull the cartridge rearwardly relative to the barrel member 18 and cartridge receiving chamber 22. The extractor is capable of some slight twisting which permits the edge portion 114 to move in a substantially axial direction as shown in FIG. 8. By virtue of this construction, if the spent cartridge tends to stick within the cartridge chamber, the edge ofthe extractor moves axially forward until the cartridge is loosened. Not only does this action increase the tendency for the edge to bite into the shell, but also once the cartridge shell begins to move relative to the cartridge receiving chamber, the spring forces inherent in the extractor tend to move it towards its normal position. This results in a faster and more efficient extraction as well as adding some snap to cause the ejection.

We claim:

1. In a cartridge-actuated fastening tool, a housing, a barrel member having a cartridge receiving chamber therein, said cartridge receiving chamber including a counterbore for engagement by the forward face ofa shoulder ofa cartridge, said barrel member being movable with respect to said housing between a breech closed position and a breech open position, an extractor member, means mounting one end of said extractor member in a stationary position with respect to said housing during at least a portion of the movement of said barrel member from its breech closed to its breech open position, the other end of said extractor positioned to extend into said cartridge receiving chamber forwardly of said counterbore when said barrel member is in said breech closed position, said other end being tapered to provide a sharp end portion, said extractor being resilient in a direction toward and away from said cartridge receiving chamber and resiliently twistable in a generally forward direction.

2. In the cartridge-actuated fastening tool of claim 1, said extractor member comprising a spring-steel member having a length greater than its width and thickness and including a portion spaced from said housing.

3. In a cartridge-actuated fastening tool, a housing having a front and rear portion, barrel means having a breech end and a muzzle end slidably mounted in said front portion for movement between a forward breech open position and a rearward breech closed position, a cartridge receiving chamber in the breech end of said barrel means including a counterbore for engagement by the forward face of a shoulder of a cartridge, firing pin means mounted in said rear portion, cocking means engageable with said firing pin means to move said firing pin means from a fired position to a cocked position as said barrel is moved into its breech closed position, means biasing said firing pin means from said cocked position to said fired position,

said cocking means including an elongated member mounted in said rear portion with the forward portion thereof extending into said front portion, extractor means having "one end attached to the forward portion of said cocking means, a groove in the breech portion of said barrel means communicating with said cartridge receiving chamber in an axial direction from the end thereof to a point forward of said counterbore, said extractor means extending into said groove when said barrel means is in its breech closed position with the other end of said extractor means being tapered to provide a sharp edge. said sharp edge extending into said cartridge receiving chamber when said barrel means is in its breech closed position,'said extractor means being resilient in a direction toward and away from said cartridge receiving chamber and resiliently twistable in a generally forward direction 4. In the cartridge-actuated fastening tool. of claim 3, said groove in said barrel means tapering forwardly and outwardly from the breech end of said cartridge receiving chamber, the taper of said other end of said extractor means being greater than that of said grove.

5. In the cartridge-actuated fastening tool of claim 4, the

width of said groove in said barrel means being greater than the thickness of said extractor means in the direction of the width of said groove.

6. in the cartridge-actuated fastening tool of claim 3. said breech end of said barrel means being reduced in cross section to provide a space between the outer wall of said barrel means and the internal wall of said housing, said extractor means having a first portion extending away from said cocking means and positioned in between said reduced portion of said barrel means and said housing when said barrel means is in said breech closed position, a second portion positioned in said groove when said barrel means is in said breech closed position, said sharp edge portion being at the terminal end of said second portion, said first and second portions being connected by an integral arcuate portion.

7. in the cartridge-actuated fastening tool of claim 6, said extractor means comprising a spring-steel member of rectangular cross section. the width in an axial direction being greater than the thickness.