US2970506A

US2970506A - Explosively actuated cable cutting tool using a live cartridge for producing gaseous pressure

Info

Publication number: US2970506A
Application number: US593069A
Authority: US
Inventors: Temple Robert; Ernest E Temple
Original assignee: Mine Safety Appliances Co
Current assignee: MSA Safety Inc
Priority date: 1956-06-22
Filing date: 1956-06-22
Publication date: 1961-02-07
Anticipated expiration: 1978-02-07

Description

Feb. 7, 1961 R. TEMPLE ET AL 2,970,

EXPLOSIVELY ACTUATEID CABLE CUTTING TOOL USING A LIVE CARTRIDGE FOR PRODUCING GASEOUS PRESSURE 2 Sheets-Sheet 1 Filed June 22, 1956 I III" INVENTORS ROBERT TEMPLE F 5" j v BY ERNEST E. TEMPLE mm QZAMMA6- Ms flmueys Feb. 7, 1961 R TEMPLE ETA 2,970,506

. L EXPLOSIVELY ACTUATED CABLE CUTTING TOOL USING A LIVE CARTRIDGE FOR PRODUCING GASEOUS PRESSURE Filed June 22, 1956 2 Sheets-Sheet 2 INVENTORS ROBERT TEMPLE ERNEST E. TEMPLE EXPLOSIVELY ACTUATED CABLE CUTTING TOOL USING A LIVE CARTRIDGE FOR PRO- DUCING GASEOUS PRESSURE Robert Temple and Ernest E. Temple, Pittsburgh, Pa.,

asslgnors, by mesne assignments, to Mine Safety Appliances Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed June 22, 1956, Ser. No. 593,069

4 Claims. (Cl. 83639) taining a bullet can be used, and in which a cable can be locked until the time comes to cut it.

According to this invention the tool includes an anvil thatwill hold a cable transversely of one end of a barrel. Preferably, the barrel is provided with a pair of diametrically opposite slots extending inward from the anvil for receiving the cable, and the anvil extends into the barrel and is removably attached to it for confining the cable in the slots. A cutting member, which is slidably mounted in the barrel, includes a piston and is normally retained in retracted position with the piston adjacent the end of the barrel opposite the anvil. A cartridge chamber communicates with the inside of the barrel behind the piston, and in this chamber there is a cartridge-receiving holder having a closed front end for retaining the bullet when a cartridge therein is fired. The side wall of the holder is provided with an opening connecting the inside of the holder with the inside of the chamber around the holder. Consequently, the gases created by the cartridge explosion will escape through that opening into the surrounding chamber and thence intothe barrel to drive the cutting member to ward the anvil.

The preferred embodiment of the invention is illus trated in the accompanying drawings, in which Fig. 1 is a side view of my cable cutting tool mounted in operative position;

Fig. 2 is a longitudinal central section of the tool;

Fig. 3 is a horizontal section taken on the line III-III of Fig. 2;

Fig. 4 is a fragmentary vertical section taken on the line IV-IV of Fig. 2; I

Fig. 5 is a vertical section on the line V--V of Fig. 3;

Fig. 6 is a front end'view of the cartridge-receiving holder;

Figs. 7 and 8 are horizontal sections taken on the lines VII VII and VIII-VIII, respectively, of Fig. 2, but with the cartridge removed; and

Fig. 9 is a fragmentary longitudinal section of a modification.

Referring to Fig. 1 of the drawings, the cable cutting tool is shown mounted in a location-where it has one of its principal uses. That is, it is shown mounted on the outer end of a swinging boom 1 that projects from one side of a helicopter (not shown) and that is used in lift ing men or articles from the ground while the helicopter is hovering. The outer end of the boom supports av sheave 2, over which a cable 3 extends. The inner end of the cable is wound on a drum in the helicopter, while the outer end is equipped with means for lifting a man or other object. The cutting tool is supported by a bracket 4 projecting from the end of the boom, and is used for cutting the cable in case the lower end of it is snagged so that the helicopter otherwise would not be able to fly away.

The tool includes a horizontal barrel 6 with an upwardly extending cartridge chamber 7 at one end screwed barrel. The stem end of the piston is tapered toward thestem to provide an annular space in the barrel behind the piston when the cutting member is fully retracted- The cutting member is normally held in retracted positionby means of a pair of plungers 12 slidably mounted in a- The.

bore extending diametrically through the piston. two plungers are urged apart and into frictional engage ment with the inner surface of the barrel by means of a coil spring 13 compressed between the plungers.

At the opposite end of the barrel there is a pair of inwardly extending slots 15 that are diametrically opposite each other for receiving cable 3 that extends verti-' cally across the barrel. Outwardly beyond the cable the inside of the barrel is enlarged and threaded for receiv-' ing a heavy screw plug that serves as an anvil 16. The

inner end of the anvil is provided with a recess 17 that receives the cut out piece of the cable and the cutter when the tool is operated. With the anvil removed, a. cable can be either inserted laterally in the barrel slots or removed therefrom.

The cartridge chamber 7. is formed by an upwardly extending cylindrical wall integral with the inner end portion of the barrel. The upper wall of the barrel is pro-- vided with an opening 18 connecting the inside of the cartridge chamber with the inside of the barrel behind piston 11. The lower end of the chamber is flat, but

is encircled by an annular shoulder 19. Screwed onto the upper end of the chamber is a collar 21 that holds the This mechanism includes a.

firing mechanism in place. flanged breech-block 22 that is gripped by the collar and which has a long integral sleeve 23 extending upward from it. Inside of this sleeve there is a firing pin 24 car ried by the lower end of a solenoid core 25 that is slidably mounted in the sleeve. against a screw plug 26 in the upper end of the sleeve by means of a coil spring 27 compressed between the lower end of the core and a shoulder in the breech-block.

Screwed onto the breech-block is a cylindrical housing 28 that contains a solenoid coil 29, which encircles the lower half of sleeve 23. The coil is electrically connected by wires 31 to an electrical plug 32 mounted on the upper end of the housing. As shown in Fig. 1, this plug is 2,970,506 Patented Feb. 7, 1961 The core normally is held connected by an electric socket 33 to an electric cable 34 that leads to an electric switch (not shown) in the helicopter. When the switch is closed, the coil will be energized and will draw the core downward to cause the firing pin to project from the lower end of the breechblock and detonate a cartridge in the cartridge chamber.

It is a feature of this invention that the cartridge chamber is equipped for receiving a standard cartridge, by which is meant one in which a bullet 36 projects from the cartridge case 37. For example, it maybe designed for receiving a 45 caliber cartridge, such as used in an army revolver. To position the cartridge in the chamber and retain the bullet when the cartridge is tired, a cartridge holder 38 is mounted in the chamber. This holder is cylindrical and is formed from heavy steel. It is provided' with a bore that extends forward or downward and that has the size and shape of the cartridge that the holder is designed to receive. The front or lower end of the bore is shaped to snugly receive the bullet, the lower end of the holder being closed so that the bullet cannot escape. To provide a space around the holder, its opposite ends are encircled by integral collars, the front one 39 being narrow and the rear one 40 being wide and provided with an annular groove 41. A cylindrical space is formed around the holder between the two collars. The side Wall of the holder, directly below the rear collar is provided with one or more radial openings. Four such openings 42 are shown 90 apart. When the cartridge is fired, the bullet cannot escape from the holder so the gases that are created by the explosion rupture the cartridge case at the inner ends of openings 42 and escape through them into thespace around the holder. Since the front collar 39 rests on shoulder 19 at the lower end of the cartridge chamber, it is necessary to provide a passage for these gases past the collar so that they can enter the back of the barrel through opening 18. This is done by cutting radial notches 43 in the front collar of the cartridge holder. To provide plenty of space for the escape of the gases, it is preferred to also provide the outside of the holder with radial channels 44 that extend from radial openings 42 forward to the notches in the collar, and to extend the notches radially inward toward the axis of the holder.

After the tool has been fired and it is desired to reload it, the firing mechanism is disconnected from the cartridge chamber by removing collar 21 and then the cartridge holder is lifted from the chamber. If it sticks in the chamber, groove 41 can be used in gripping it to pull it loose. In order to facilitate removal of the fired cartridge from the holder, the latter is split lengthwise into at least two parts which can readily be separated when the holder is taken out of the cartridge chamber. The exploded cartridge can be lifted from the segment of the holder in which it rests. The holder then is re-assembled and dropped into the cartridge chamber, and a new cartridge is inserted in the holder, after which the firing mechanism is reconnected to the chamber.

It will be seen that with this cutting tool a cable can be held in cutting position until the tool is fired, and then a new cable can be quickly put in place without having to thread it through the tool. Also, the tool uses standard ammunition and is not rendered inoperative by the lack of special blank cartridges. After firing, the used cartridge can easily be removed from the tool and replaced by a new one. The enlarged piston 11 serves as a stop that arrests the forward movement of cutter so that it will not knock anvil 16 out of the barrel, which it otherwise might do because slots so weaken the barrel wall that it could be spread if the cutter hit the anvil hard enough.

If it is desired to use a free cutter; that is, one without an arresting enlargement, the modification shown in Fig. 9' can be used. In that embodiment the barrel 50 is pro vided with a pair of cable receiving slots 51, and the outer end of the barrel is enlarged internally to form a recess.

An anvil 52 is held in this recess by a collar 53 screwed onto the barrel. The anvil may have a stem 54 extending through the collar and held therein by a spring washer 55. When the tool is fired, the collar will not separate from the barrel even though the cutter is free, because the slotted end of the barrel cannot spread open and release the anvil due to the encircling collar.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what We now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. In a cable cutting tool, the combination with a barrel, means including an anvil for holding a cable transversely of one end of the barrel, a cutting member slidably mounted in the barrel and including a piston, means normally retaining said member retracted with its piston adjacent the end of the barrel opposite said anvil, and a cartridge chamber communicating with the inside of the barrel behind said piston, of a hollow holder in said chamber having a continuous side wall and a closed front end defining a bore therein, said holder being mounted with the front end thereof adjacent the barrel and being adapted to snugly receive a cartridge containing a bullet, said holder substantially completely enclosing said cartridge on the front and sides thereof, means in said chamber cooperating with said holder to prevent axial movement of the holder in the chamber, means pro viding a backing surface for the end of the cartridge opposite the front end of said holder, means behind the chamber forfiring a cartridge in said holder, and passage means connecting said bore with said barrel and of sufficient size that the gases created by the cartridge explosion will rupture the cartridge case at said passage means and escape therethrough to said barrel to drive said cutting member toward said anvil.

2. A cable cutter according to claim 1, in which said cartridge holder is split into a plurality of parts that can be separated to remove an exploded cartridge from the holder after the holder has been removed from the cartridge chamber.

3. A cable cutter according to claim 1, in which the opposite ends of said cartridge holder are encircled by integral collars to space the intervening area of the holder from said chamber, and said passage means including a radial notch in the front collar.

4. A cable cutting tool comprising a barrel provided with a pair of diametrically opposite slots extending inward from one end for receiving a cable extending across the barrel, an anvil extending into said end of the barrel and removably attached thereto for confining the cable, a cutting member slidably mounted in the barrel and including a piston, means normally retaining said member retracted with its piston adjacent the end of the barrel opposite said anvil, a cartridge chamber conmunicating with the inside of the barrel behind said piston, a hollow holder in said chamber having a continuous side wall and a closed front end defining a bore therein, said holder being mounted with the front end thereof adjacent the barrel and being adapted to snugly receive a cartridge containing a bullet, said holder substantially completely enclosing said cartridge on the front and sides thereof, means in said chamber cooperating with said holder to prevent axial movement of the holder in the chamber, means providing a backing surface for the end of the cartridge opposite the front end of said holder, means behind the chamber for firing a cartridge in said holder, and passage means connecting said bore with said barrel and of a sufiicient size that the gases created by the cartridge explosion will rupture the cartridge case at said passage means and escape therethrough to said barrel to drive said cutting member toward said anvil.

References Cited in the file of this patent UNITED STATES PATENTS Bogoslowsky Jan. 26, 1932 10 Allen et al. Nov. 7, 1933 Temple Oct. 15, 1935 Temple Dec. 13, 1938 Martin Dec. 7, 1943 Phelan Nov. 16, 1948 Matthysse Nov. 27, 1951 Kane June 5, 1956 FOREIGN PATENTS Germany Aug. 30, 1933