US2799108A - Cartridge extractors - Google Patents

Description

R. J. KOPF El AL 2,799,108

CARTRIDGE EXTRACTORS July 16, 1957 Filed April 16, 1954 2 Sheets-Sheet l INVENTORS,

ROWLAND J. KoPr ROGER MARSH A TTORNEYS.

July 16, 1957 R. J. KOPF ET AL 2,799,

CARTRIDGE EXTRACTORS Filed April 16, 1954 2 Sheets-Sheet 2 INVENTORS, ROWLAND J. KOPF' ROGER MARSH ATTORNEKS CARTRIDGE EXTRACTQRS Rowland J. Kopf, Rocky River, and Roger Marsh, Hudson, Ohio, assignors to Ramset' Fasteners, Inc, a corporation of Delaware Application April 16, 1954, SerialNo. 423,556

8 Claims. (Cl. 42-25) This application relates generally. to apparatus for firing cartridges,'a'nd more particularly; to extractors for use where extremelyhigh breech pressures are encountered.

In the operation of powder-actuated tools, for example, it would be desirable to provide for breech pressures as high as and higher than seventy-five thousand pounds per squareinch While using conventional cartridge cases, particularly rim fire cartridges. Heretofore, this has not been feasible because of the extraction difficulties that arise when such pressures are developed.

The conventional claw type of extractor requires an extractor cut or recess in the breech of the barrel, with the'result that the case is in part unsupported and' may rupture under high pressure or be so weakened as'to separate during extraction. The barrel-segment type-of extract-or provides better support, but as heretofore-known, extends only a short distance lengthwise of the-chamber. Those experienced in the art have believed that theforward'transverse edge of the extractor should lie-near the rim of the case so that the forward portion of the chamber iscircumferentially complete, but such a construction is not too satisfactory under conditions of very high pressure, there being a transverse irregularity in the wall of the chamber beneath the case andthe area of contact between case and extractorbein-g necessarily limited.

It may be noted that thesedifliculties become acute when rim-fire cartridges are-used, as this'type of case must be formed of soft metal. Accordingly, it'is'an object of the invention to provide an improved extractor particularly adaptedfor apparatus utilizing rim-fire cases at pressures higher than those heretofore considered practical.

Briefiy, a barrel-segment type of extractor is recessed within the barrel of the device for axial movement, but the extractor extends substantially to and preferably beyond the mouth of the case. When practical, the forward end of the extractor is formed with an inwardly projecting lip, which overhangs the mouth edge of the case. "With this arrangement, the case'is fully supported; there is-no transverse irregularity between the walls ofthe'case and chamber; and the case is engaged by the extractor over a considerable portion of its area.

Other features of the invention will be in part apparent from and in part pointed out in the following detail description taken in connection with the accompanying drawings, in which: i

Fig. 1 is a longitudinal sectional view of the breech portion of a powder-actuated tool embodying the invention, the breech being closed;

Fig. 2 is a view similar to that of Fig. 1, but with the breech opened;

Fig. 3 is a cross section taken on the line 3-3 of Fig. 1;

Fig. 4 is an end view of the barrel shown in Fig. 1;

Fig. 5 is a side elevation of the barrel with the extractor in its innermost position; and

Fig. 6 is a perspective view of the barrel shown in Fig. 5, but with the extractorin its retracted position.

lnitially, it will be understood that in powder-actuated tools, the cartridge is the wealc The chamber. andbolt can be made to handle pressuresmuch" higher than those that the case can withstand, yet the case is essential, not only from the viewpoint of convenience, but also because of its obturating action. As maximum-pressure is approached before the fastener startsto move, thecase expands into tight engagement withthe wall. of thechamher to seal against rearward escape of gas. .Mo st existing devices require thatthe case thencontract as the pressure drops so as to permit easy extraction. When thebreech pressure is excessive, however, the" case will rupture, un less properly supported; or it will fail tov contract Suflie ciently to permit easy extraction, and inmost instances,; the maximum permissible breech pressureof the device'is; determined by the failure of; the. extractor to perform: reliably above that pressure. 1

Conventional extractors may be considered as falling. into one of two basic classes In one form; a radiallydisplaceable claw is attached to; the, bolt oirbreecln'block so as to slip over the'head of the: case: into engagement with the rim as the breech is closed, the claw functioning;

to withdraw'the case from thechamber when. thebre'e'ch is opened. In the other type of extractor, aniaxi'allymovable part forms a segment of the rear face; of; the; barrel; so that when the. breech is. closed; the cartridge: rim is forced against the rear face of the barrel, includ-'- ing the extractor segment;.andwhen the;breeclr' is opened, a cam moves the extractor segment rearwardlytowwitb, draw the case. 5 7

- The claw type. of extractor is best adapted to a; bolt-- action, and. while the bolt: action is very-strong, theiclaw: type of extractor: is comparatively weak. This is so:because. the barrel must be' cut awayl'to accommodate the extractor, thereby leaving a portion of'the'case' without support and hence subject to rupture. Also, the extractor hook. or claw is usually spring biased-rather than positively: locked to the case; and hence tends to slips off the rim. if the case'does not pull easily'from the'cham'bers The barrel-segment type of'extractor'aiford's b'etter sup-= port for the cartridge, but'its' use has been limited' to relatively weak' hinge actions; Also,- itv has been, (rus tomary to form theextractor piece in amanner'such that it takes up only a relatively small portion of 'the firing:

- chamber, the transverse forward edgeof theextr'a'ctor breech pressures, as for example, pressures in excess of seventy-five thousand pounds per square inch, have been.

hindered by extractor failures, and this has been soespe cially when the cartridge is of a rim-fire type. Rim-tire cases are relatively inexpensive to make and therefore particularly desirable in powder-actuated tools, but'their field of use has been restricted. The explanation is that a rim-fire case must be of soft'meta'l' (usually copper) so that the rim will crush and ignitethe primer under impact of the firing pin, whereas center-fire casesmay be made of tougher and more resilient brass, only the, primer itself being encased in soft copper. ently weak, the rim-fire type of case is more likely to rupture if not fully supported. Also, the soft'rnetaldoes not contract properly when subjected to considerablepressure. Instead, the case becomes sealed or; frozen'into the irregularities of the chamber so thatconsiderable extraction force is required. This tendency to'fre'eze' is especially aggravating inasmuch as the softmetal' of the case is easily torn, the extractor tending to tearthrough the rim' or' separate the'entire head; i I

' Referring now to the drawings, there'isshown the Being inher:

breech portion of a cartridge-firing device embodying the invention. In order to simplify the disclosure, only those details of the structure relevant to the invention are described, but it will be understood that theillustrated section would form a part of a complete powder-actuated tool, such as that disclosed in our copending application Serial No. 355,034, filed May 14, 1953, of which this application is a continuation-in-part.

This tool includes barrel and receiver assemblies which open by means of a hinge connection, but a bolt-action type of breech closure is also incorporated. A barrel 1 is mounted in a housing 3, which is hinged at 5 to a receiver- 7. This receiver in turn contains a bolt or breech block 9, which looks directly onto the barrel. More particularly, the barrel 1 telescopes within a recess inthe' block 9 and has external lugs 11, which engage with internal lugs 13 formed in the bolt recess. Similar lugs 15 and 17-'are provided to lock the barrel housing 3 to the receiver 5. Partial rotation of the barrel assembly 1 and 3 relative to the receiver assembly 7 and 9 uncoupl'esthe lugs to permit initial opening of the breech by relative axial movement of these parts, and in this respect, the device possesses the high strength of a bolt action.

If desired, and as explained in the aforementioned application, the inner elements 1 and 9 may be arranged for rearward movement as a unit within their housing sections 3 and 7, but the barrel 1 should be locked against rotation within its housing 3 and the bolt 9 should be locked against rotation within its housing 7. This may be accomplished in various ways, as by splines (not shown). Also, it will be understood that springs (not shown) would be provided in the manner described in the aforementioned application to bias the bolt forwardly I against a shoulder 18, so that the bolt would be held in a forwardmost position during closing of the breech, while permitting rearward movement upon application of force to the muzzle of the barrel.

The hinge connection 5 between the barrel housing and receiver is designed to permit rotary unlocking of these parts followed by axial and then swinging separation. Ahinge ring 19 encompasses the receiver 7 within an annular groove 21. A pair of cars 23 project forwardly from the ring 19 between a pair of brackets 25, which'extend rearwardly from the barrel housing 1. A pivot pin 29 is carried by the brackets through elongate openings 27 in the ears 23, thus permitting limited axial or telescoping separation of the receiver relative to the barrel.

To open the breech, the receiver 7 is first rotated over F a limited arc (determined by a stud 31) within the ring 19 to disengage both sets of locking lugs. The receiver is then pulled away from the barrel housing in an axial direction to clear the bolt from the barrel, the pivot pin 29 moving to the other end of the slotted openings 27,

whereupon the receiver may swing down to expose the breech.

When the breech is closed, the bolt face 33 is brought up against the breech 35 of the barrel. The bolt face is substantially flat but for an opening 37 for the firing pin (not shown), and is of a diameter corresponding to the outer diameter of the barrel lugs 11. The breech 35 is also flat but is of a reduced diameter, the reduction being somewhat less than that of the inner diameter of the barrel lugs in order to accommodate an extractor lifting ring 39. This lifting ring 39 is of an outer diameter equal to or slightly less than the inner diameter of the barrel lugs 11, so that the lugs 13 on the breech will clear the ring. The reduced section of the barrel extends from the breech 35 an amount such as to leave a portion 41 projecting rearwardly from the ring, and this projecting portion 41 accommodates a pair of opposed lugs 43, which overlie the ring.

These lugs 43 form a part of an extractor 45, which is recessed at 47 within the barrel and which is mounted for k of the case.

relative axial movement with respect to the barrel. As best shown in Fig. 3, the cartridge case is transversely embraced over a segment corresponding to half the circumference. Otherwise, the extractor extends longitudinally the length of the firing chamber, and it may be formed with a lip 49 which overhangs the mouth edge of the cartridge case 51. The inner face of the extractor thus defines a substantial part of the firing chamber. The cross-sectional shape of the recess 47 and the extractor may be rectangular, so that the recess may be easily milled in the barrel, and in that event, the side walls 53 (Fig. 3) may be approximately tangential with the circumference of the chamber. Both the breech and extractor are counterbored at 55 to recess the rim 57 of the cartridge case, thus providing a strong support for the case. Also, the rear portion 41 of the barrel is recessed to accommodate the lugs 43 of the extractor when the breech is closed (Fig. 5).

As best shown in Figs. 4 and 6, the lifting ring 39is formed with a projecting lip 59, which is aligned with one set of the barrel lugs 11, and the barrel may have a lug removed adjacent the ring to provide for clearance.

In operation, the breech is opened by rotating the receiver to disengage lugs 13 and 15 from the barrel lugs 11 and 17; in which event, the lugs 13 are also cleared from the lip 59 of the lifting ring, thus permitting the receiver to be drawn rearwardly. When the receiver is then hinged back upon the pin 29, the mouth-edge portion 61 of the receiver engages the lip 59 to pry the lifting ring rearwardly, as shown in Fig. 2. The ring, in turn, engages the extractor lugs 43, thus causing the extractor to be drawn rearwardly and expose the rim 57 The case can then be easily removed and a new cartridge loaded.

From the foregoing, it will be apparent that the extractor of this invention is readily constructed and simple in operation. Moreover, positive extraction is assured inasmuch as the case is engaged over a substantial portion of its area by the extractor. The case itself is supported at all points, so that high-powered charges may be used without danger of case rupture during firing or case tearing during extraction.

Preferably, the extractor is used with a combination bolt and hinge breech action as disclosed, but this is not essential. Additional variations and modifications will be apparent to those skilled in the art. For example, it may be desirable to eliminate the forward lip 51 on the extractor, when the bore of the barrel is of the same diameter as that of the firing chamber. Elimination of this lip would then permit breech loading of fasteners of a diameter equal to that of the cartridge case. Also the cross-sectional shape of the extractor may be varied, although it is desirable that the fit of the extractor with the barrel be relatively close in order to minimize gas leakage. With the shape disclosed in Fig. 3, the expansion of the case at the instant of firing will drive the lower portion of the extractor into sealing engagement with the barrel and may also bend the side portions 53 into similar sealing engagement with the barrel.

The firing chamber per se is not interrupted in a transverse direction, the lines of interruption at 53 being longitudinal instead. Contrary to expectation, the fact that these interruptions extend the length of the case does not result in any serious complication in leakage.

Although one embodiment has been disclosed in detail, it is to be understood that the invention is not limited thereto, but the drawings and description thereof are to be understood as being merely illustrative. It is realized that many modifications and variations will present themselves to those skilled in the art without departing from the spirit of this invention or the scope thereof as set forth in the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In cartridge-firing apparatus comprising a barrel having locking lugs and a bolt-action type of receiver assembly having cooperating lugs, said barrel being formed with a chamber; the improvement comprising an axially-movable extractor element recessed within and forming a part of said chamber, said extractor having a lip engaged by said receiver assembly upon opening of the breech to actuate said extractor, said lip being aligned with said barrel lugs to clear with the receiver lugs upon opening of the breech.

2. Apparatus as set forth in claim 1, further including a lifting ring encircling said barrel adjacent the breech rearwardly of the barrel lugs, said lifting ring being of an outer diameter less than the inner diameter of the barrel lugs, and having a radially-projecting lip aligned with said barrel lugs.

3. Apparatus as set forth in claim 1, further including a hinge connection between said receiver assembly and barrel, said hinge connection permitting relative rotary movement between the barrel and receiver assembly and also relative axial movement.

4. Apparatus as set forth in claim 3, wherein said receiver assembly is mounted for rotary movement within an encircling member, said encircling member being secured to a hinge element, a cooperating hinge element for said barrel, and a slot and pin lost-motion connection between said hinge elements.

5. In cartridge-firing apparatus having a barrel formed with a firing chamber, and a cooperating receiver assembly having a bolt movable axially relative to the barrel and formed with locking lugs rotatable with respect to the barrel; the improvement that comprises an extractor segment recessed within the breech of the barrel so as to form a part of the firing chamber, said extractor segment being axially movable from the barrel to extract a cartridge and having a radially-projecting lip, and means on the receiver assembly engageable behind the extractor lip when the locking lugs are rotatably disengaged preparatory to axial opening of the breech and thereafter actuating said extractor as the breech is opened.

6. In cartridge-firing apparatus having a barrel and receiver assembly movable axially relative to one another; the improvement that comprises said receiver assembly having a breech bolt formed with locking lugs which are rotatably engaged to lock the breech, an extractor segment recessed within the barrel for axial movement relative thereto, said barrel and extractor segment each forming a part of a firing chamber, and cooperating means on said extractor segment and said receiver assembly adapted for axial cooperation with one another when the breech bolt is rotated to disengage the locking lugs and unlock the breech preparatory to axial opening thereof, said means cooperating to actuate the extractor as the breech is opened.

7. In cartridge-firing apparatus having a receiver and a barrel mounted for axial movement relative to the receiver, the barrel being formed with a firing chamber; the improvement in an extractor comprising an axially movable element recessed within the barrel and forming a part of the chamber, a lifting ring circling the barrel adjacent the breech end thereof, said extractor having a lug overlying said lifting ring, and means on the receiver engaging said lifting ring upon opening of the breech to actuate said extractor element.

8. A powder-actuated apparatus having in combination a forepart including a barrel and a rear part including a breech block and firing pin, a hinge connecting said forepart and said rear part, an extractor segment recessed within said barrel with axial movement relative thereto, said extractor segment forming part of a firing chamber for receiving a cartridge, interlocking elements on said fore and rear parts for locking the fore part and rear part in firing position, said interlocking elements being relaitvely movable axially of the barrel between a position whereat movement about said hinge is prevented and another position whereat said movement of said hinge is permitted, said extractor having an actuator disposed in the path of movement of said rear part when the latter is moved about said hinge, and said actuator being disposed clear of the path of the relative movement in the axial direction of said fore part, whereby movement of said ejector occurs only upon movement about said hinge and movement about said hinge depends upon precedent movement in the axial direction.

References Cited in the file of this patent UNITED STATES PATENTS 1,077,103 Smith Oct. 28, 1913 1,538,561 Koller May 19, 1925 2,237,601 Holek Apr. 8, 1941 2,457,354 Dial Dec. 28, 1948 FOREIGN PATENTS 24,502 Great Britain 1893

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