DE2317930A1 - METHOD AND DEVICE FOR SEPARATING A MECHANICAL PART BY USING THE ENERGY OF AN EXPLOSIVE - Google Patents

Description

Method and apparatus for separating a mechanical part by using the energy of an explosive

The invention relates to a method and devices for cutting a mechanical part, for example a wire, a rod, a plate, etc. using the energy of an explosive.

This method is carried out with a device that has a chamber into which the part to be separated and an explosive charge is introduced, which is arranged so that they directly or indirectly via an interposed part on the part to be separated as a result of the parts released by the explosion Gas exerts a shear pressure.

With the invention it is possible. the parting of a metallic one Part and, if necessary, the movement of the separated part via: r a certain distance with a response time of about 10 "s from the time the ignition command is applied.

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With the invention, moreover, such operating conditions are created that the same separating devices in the response time only differ by a few microseconds.

These excellent properties, which, as far as is known, have not yet been achieved, offer new uses, as will appear from the following, and require a combination of means, one of which is the Use of a high powered explosive that is difficult to use industrially.

However, the invention makes it possible to meet the conditions for the use of such an explosive without damage of the device and without special protective measures.

The invention finally creates these conditions in a device with limited dimensions, which are given in the following with exemplary embodiments and which the use of this device in electrical Allow installations, for example in breakers.

According to the invention is a method for separating a mechanical Part, for example a wire, a rod or a plate, characterized in that the cutting of the part is carried out by pure shear loads under the action of shear forces caused by the explosion of explosives generates v / earth which has a mass energy of more than 1000 joules / gram, preferably 2,000 to 5,000 J / g, and a detonation speed of more than 3,000 m / s, preferably 7,000 to 8,000 m / s that the charge in one Recess is arranged on a limited area of the part to be separated or one directly or indirectly on a limited area of the part to be separated, moving

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union part and that the initial volume of the explosion gases is at most equal to the volume of the limited area adjacent to the recess of the charge is coated during the useful movement of the separated part or the movable part.

The invention is based on the idea, among other things, the extraordinary effectiveness of pure shear for the maximum limitation of energy and cutting time to use.

Namely, if Δ a is the elastic sliding caused by a Cutting force T is caused, which corresponds to the shear breaking force P for a given cross-section, is obtained man:

Aa _ P
a ~ G *

In it are;

a: thickness of the part to be cut,
G: shear modulus of elasticity = 0.38 E, E: Young's modulus,

For brass: P = 350 Newton / mm ²
G = 40,000 N / mm ² .

Aq

Assume that P and ---- v / are constant during shear

Aa-?

stay, so is ~~ ^ '1'1O. The shear is thus achieved as soon as the crystals have moved a distance of about a 10 in the shear plane. The shear energy is

T'a ^c 10 "" ^{2 T:}

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The shearing process is extremely fast due to the short distance on which it takes place. He will enter as soon as the shear stress exceeds a threshold, which must therefore be reached quickly, for which purpose according to the invention an explosive with a high detonation velocity higher than 3,000 m / s, preferably 7,000 to 8,000 m / s, and a mass energy of more than 1,000 J / g, preferably 2,000 to 5,000 J / g, is used, so that the Gas pressure acting directly or indirectly on the part to be separated before any geometrical change in the separating device is brought up to a height in less than a microsecond by moving this part, which is above the level corresponding to the shear threshold and for the time required for this process this level is maintained.

To avoid any damage to the separator through use to avoid explosives with high detonation speed and high internal energy, it is of Meaning that most of this energy is used quickly in the shearing process and, if necessary, shearing and moving processes will. This consideration leads to the fact that on the one hand the sheared part is given the least mass and that on the other hand the device is designed so that the Yizrkungsgrad the conversion of the internal energy of the explosive into mechanical and kinetic energy is maximum.

Investigations have shown that this result is practically reached when the gas is given before every movement The initial volume is at most equal to the volume of the gas during the useful movement of the sheared part is coated.

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The initial volume can be at most equal to the co-volume of the explosive, which is why according to the invention it is preferably white uses an explosive with high mass energy and at the same time with a high detonation speed, as in the Trade under the name Hexogen, Oxtogen, Pentrit, Tetryl, Trinitrotoluol, etc. is known.

The invention is described by way of example with reference to the drawing. Show in it:

Fig.1 is a sectional view of a quick disconnect for high currents according to an embodiment of the invention and

Fig.2 is a sectional view of a quick disconnect for high currents according to a second embodiment of the invention.

The interrupter shown in Figure 1 has two terminals and 2, the terminal 1 is mounted on a metal body 3 and is isolated from this by a set of insulating washers 4 and 5, which are pressed by two nuts 6. The clamp 2 is mounted on a metallic cap 8, of which it is also through a. Set of insulating washers 4 and 5, which are pressed into place by two nuts 6. An electrical contact member 7 is electrically connected to the terminal 1 and consists of sections which have been cut out of a cylinder through a series of slots and which are clamped in place by a spring 9. A metal part 10 is screwed onto the terminal 2 and enters the contact member 7 with friction when the cap 8 is screwed onto the body 3. On the metal part 10 there are two grooves 11 and 12 which form predetermined breaking points and which determine the area of the shear action.

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In the metal part 10 a recess 13 is provided in which an explosive charge 14 and an ignition block 15 are located, which is provided with terminals passing through the body 3, the contact member 7 and the metal part 10. The The explosive charge 14 is technologically independent of the ignition block 15, so that the two parts are only present in the eye be brought into contact with the closing of the device before possible use (safety in handling) and thus, on the other hand, any explosive can be used with a given detonator block 15 (Standardization). Between two mutually coaxial parts of the clamp 2 and the metal part 10 is an insulating ring 16 used. A lead ring 17 is provided in the interior of the contact member 7. When the ignition command through the connections is transferred to the ignition block 15, the explosive charge 14 explodes. The gas pressure sets the metal part 10 in the through the grooves 11 and 12 from certain range of shear forces. The shear break occurs as soon as these x "forces exceed a certain amount. The upper part of the metal part 10 is now driven upwards at great speed. If it is at a sufficient distance from the abandoned contact, it will be through the lead ring 17 stopped, v / obei its kinetic energy thanks to the end of the upper part of the metal part 10, which is a Profile with a triangular edge, is converted into a permanent deformation of this lead ring 17.

Such a breaker, which is in the shape of a cylinder with a diameter of 45 to 50 mm and a length of 75 mm, is dimensioned for a continuous current strength of 600 to 800 amperes and is charged with 100 mg of pentritol, leads the interruption in 150 microseconds from the ignition command. With an interruption, the shearing of the part by the 1.5 to 2 mm spaced apart grooves 11 and

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is delimited, and then the separation and propulsion of the movable upper part of the metal part 10 · over understood a distance of about 5 mm.

The breaker shown in Figure 2 causes the break a calibrated lamella or plate by shearing and by moving the sheared part. The calibrated The lamella or plate can be a calibrated prism-shaped fuse link.

The breaker has a metallic body 21, in which a metallic i'eil22 is provided, which with a recess 23 is provided. In this recess are a filament igniter 24, an explosive charge 25 and a Anvil 26 made of metal is provided. In the metal part 22 are two bores for the implementation of the connecting wires of the detonator provided. The detonator 24 and the explosive charge 25 are from those in the description of the preceding Device mentioned reasons technologically separated from each other. A part 27 is made over the anvil 26 Insulating material, such as nylon, celoron and the like. Arranged, which has the shape of a parallelepiped and a Has recess into which the head of the anvil 26 is inserted.

The conductor 28 to be separated consists of a calibrated one Fusible link with a width of 25 mm and a thickness of 2.5 mm, the two rows of arranged in a line Has perforations which are spaced from one another by the width of the part 7 and opposite to two parallel Edges of part 7 are located. On the body 21 is a cover 29 made of insulating material, for example made of nylon or Celoron, screwed on, which has two openings 30 for the passage of the conductor 28 and a recess 31.

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When the firing command is transmitted through the terminals to the igniter 24, the wire instantly melts and causes the explosion of the explosive charge 25 · The pressure of the explosion gases hurls the anvil 26 and the part 27 afterwards Above, the calibrated conductor is sheared off at the point of the perforation lines, the sheared off part of the conductor 28 and the insulating part 27 are driven into the recess 31 and the isolating part 27 pushes itself between the ends of the calibrated conductor so that the risk of flashover is limited.

Such a breaker which has the shape of a cylinder with a diameter of 55 mm and a height of 45 mm and is charged with 20 mg lead nitride and 20 mg pentrite, causes the interruption of a calibrated fuse link or Conductor with a useful width of 20 mm and a thickness of 2.5 mm in 155 microseconds, with an interruption the shear of the conductor and the rectilinear movement of the sheared part by 5 mm is understood. Yes after its nature, the insulating part 27 can on its side in contact with the conductor with a metal lamella be occupied, which facilitates the shearing.

The separation energy can be reduced in that the to separating fuse link is exposed to the overcurrent to which the separating device reacts. The one in the fuse link Developed thermal energy reduces the shear energy.

If necessary, the sheared part of the conductor can come into contact with two poles at the end of the stroke and thereby close a control or measuring circuit.

In addition to the advantage that they can be operated in a very short time of less than 10 "s and with deviations in the operating time of

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work less than a few microseconds Invention devices have the advantage that they can be used in all cases in which the switching elements are inaccessible during operation, for example when working underwater at great depths, when working underground Work and in the field of space travel. They can be used in any electrical circuit that is very much requires rapid protection in the event of accidental overload. The very slight variation in the operating time of such Devices also allow their arrangement in series; the almost simultaneous operation in this way allows the Execution of interruptions or the connection of a considerably higher power than is possible with a single device it is possible.

Claims

409808/0344

Claims (1)

Claims Λ Procedure for separating a mechanical part, for example a wire, rod or plate, characterized in that the part is separated by pure shear loads under the action of shear forces, the generated by the explosion of explosives which have a mass energy of more than 1,000 joules / gram, preferably 2,000 to 5,000 J / g, and a detonation speed of more than 3,000 m / s, preferably 7,000 to 8,000 m / s, have the charge in a recess is arranged on a limited area of the part to be separated or a direct or indirect a limited area of the part to be separated resting, movable part opens and that the initial volume of the Explosion gases is at most equal to the volume of the limited area adjacent to the recess of the charge is coated during the useful movement of the separated part or the movable part. 2. The method according to claim 1, characterized in that it is used for the separation of an electric current flowing through it Ladder is applied. J. Device for carrying out the method according to claim 2, characterized in that the part to be separated has a metallic cylinder which is extended by a ring is, the inner diameter of which is substantially equal to the outer diameter of the cylinder and that of a electrical terminal is attached that the cylinder is in electrical contact with a second terminal that in the Connection area between the cylinder and the rim by two mutually coaxial grooves with the same diameter 409808/0344 messer'eine predetermined breaking point is formed, and that the cylinder has a recess for an explosive charge and its detonator. A. Apparatus according to claim 3 »characterized in that the contact between the cylinder and the second terminal via a with the second terminal connected contact member is formed, which has the shape of a ring through a series of Slots is divided into sections which are clamped in place by an annular spring. 5. Apparatus according to claim 4, characterized in that im Inside the contact member a deformable, for example made of lead ring for damping the kinetic Energy of the cylinder is arranged. 6. Device according to one of claims 3 to 5, characterized characterized in that one of the terminals is mounted on a metal body from which it is isolated from that of the other Clamp is mounted on a cap, from which it is also isolated, and that the body and the cap together are firmly connected. 7. Apparatus for performing the method according to claim 2, characterized in that the part to be separated is the mold has a lamella which traverses the insulating cover of a housing, which consists of a metallic body and a insulating, screwed to the metallic body cover consists that a metal part is arranged in the body is that with a recess for receiving an explosive charge, their detonator and a metallic anvil arranged on the explosive charge is provided ο, and that between the An insulating part is arranged on the anvil and the part to be separated. 409808/0344 8. Apparatus according to claim 7, characterized in that the metallic lamella is the surface of the insulating part covered. 9. Apparatus according to claim 3 or claim 7, characterized characterized in that the part to be separated is exposed to the overcurrent to which the separator is responsive. . 10. Apparatus according to claim 3 or 7, characterized in that that the explosive charge is technologically independent of the detonator with which it is in contact. Α09808 / 034Λ Blank page