DE2108485A1 - Method and device for high-energy pulse machining of materials. Compaction, extrusion, forging and the like - Google Patents

Description

r. 27-T.I.617079 February 19, 1971

Bolt Associates, Inc., Norwalk, Connecticut / USA

Methods and devices for high-energy pulse machining of materials, compression, extrusion, forging and the like.

The invention relates to a method and a device for f Processing of materials with high energy pulses. In particular, the invention relates to a method and an apparatus for high-energy impulse compression of powdery material into products of high quality in their structure as well as on the high-energy forming and forging of materials in Dies,

US Pat. No. 3,376,723 shows methods and devices for reshaping material by means of sudden impulses. As described there, a freely movable piston mass is accelerated in the direction of a second piston, in which trapped gas under high pressure is suddenly released Λ. The second piston is separated from the material to be formed by a pressurized liquid which is arranged adjacent to the material, so that the momentum generated by the impact of the accelerated mass on the wide piston creates a I-hole pressure shock wave in the liquid, whereby the material is driven into the shape specified by a die.

In the method and the device for high-energy impulse material forming according to the present invention

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an accelerated piston mass on a double piston hammer device composed of a pair of pistons separated by a pressurized liquid, so that an effective device, rigid in its effect, for transmitting the impulses to the material to be machined is created.

An advantage of the present invention can be seen in the fact that a die connected to one of the two pistons in direct contact with the material to be processed. A mechanical reinforcement of the high energy impulse can be achieved in that the section of the piston which is in contact with the material is in a suitable manner Way shapes.

A significant field of application of the invention lies in a method and an apparatus for high energy compression of powdery material in a vacuum for production of products of high quality in their structure. Powdery material, such as metal powder or powdery refractory material is placed in the cavity of a die; one on one of the pistons of the double piston hammer device according to the present invention attached die is used to compact the powder with this in Brought work contact. The liquid located between the two pistons in the double piston hammer device is pressurized to make the double piston rigid as well as to pre-compress the powdery material. Then a piston mass is accelerated along a cylinder and strikes the double piston hammer belt. tung, whereby, a Hoelieriergieiwpuls between the powder, de :?

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Die compressed so that its particles become hostile and a high quality component is created. One can receive impulses of very high energy and of sufficient size to firmly bond the powder particles together into one high quality product that corresponds exactly to the die shape.

Particular advantages of the method and devices according to this invention result in the vacuum forming of powdery Material for products of high quality in their internal structure and precise in their dimensions if the powder is evacuated after filling, preferably to a high vacuum, then the powder compressed by a high energy pulse by means of an accelerated piston mass acting on a double piston hammer suggests that has a die that is in contact with the powder. This high-energy vacuum forming of powdery Materials maintains their purity and improves the quality control of the end results because a connection of the particles is achieved to a dense homogeneous part.

Another advantage of the present invention is that high precision parts with common high energy forming Deformation degrees can be produced, with precise control of the conditions for (a) the pre-compression, (b) the applied final pressure and (c) the degree of deformation of the material to be deformed.

Further features, advantages and possible applications of the new invention emerge from the following illustration of exemplary embodiments and the drawing.

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Show it:

1 shows a section to explain the method and the device according to the present invention for processing material with high-energy pulses, for example for processing a powdery material with high-energy pulses, for example a powdery material, the different Control devices of the device are only shown schematically,

2 shows a section through the double piston hammer device, those in the method and apparatus for processing powdery material explained in FIG. 1 Material with high energy impulses is used,

Fig. 3 shows in section the double piston hammer device, the in the method and the device according to FIG. For transfer molding of material in a die and

Fig. H a section through a part of the dual piston hammer device in the method and the apparatus according to Fig. 1 is used to forge a material.

1 shows a method for machining material by means of high-energy pulses and a corresponding device 10, which includes a heavy duty high pressure press 12 having a die part 14 and a pulse generator aligned with a double piston hammer device 18

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holds, which has a die part 19 which is in contact with the powdery material 20, which is in a cavity 22 of the die part 14 is arranged.

The double-piston hammer device 18 is arranged in the bore 24 of its hammer cylinder 25 and consists of an impact-absorbing piston 26, a column 28 of pressurized hydraulic fluid and a piston 30 carrying a die. The piston 30 carrying the die is in the shown embodiment equipped with a compression die part, the cross-sectional area of which is smaller than that of the main body of the piston 30, so that a pulse amplification is achieved. The compression die part 19 has the shape of a rod-shaped punch and is screwed to the piston 30 by means of a threaded projection 32 and protrudes from the lower surface 34 of the piston 30; the punch is shaped so that it encloses a die chamber 36 between the lower surface 34 and the die part 14 when the die 19 is in working contact with the powdered material 20. Ä

The chamber 36 can be evacuated by a high vacuum pump 37 are in operative connection with the chamber 36 by a line 38 and a passage opening 40 in the lower Die part 14 is standing. The passage opening 40 and the line 38 are sized enough to create a high vacuum in the chamber 36 associated with the die cavity 22 through the gap 42 between the compression ram 19 and the lower die part 14 is in communication. The cylinder 25 is pressure-tightly connected to the die 14 by suitably arranged seals 44, so that in the die cavity 22 a

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clean atmosphere for powder processing in the form of a high vacuum can be created if so desired.

The column 28 of hydraulic fluid is through an opening 47 by means of a solenoid operated valve 49 through a hydraulic pressure control and a liquid storage container 45 pressured. The liquid column 28 can be relieved of pressure to prevent the piston from falling 26 to enable. The liquid column 28 has a sufficient vertical height to precompaction of the powdery To achieve material 20 in the desired degree. The greater the amount of liquid 28 through the reservoir 45 exerted pressure, the greater the compression of the powdery material 20 and the greater the vertical Distance between the double pistons 30 and 36.

During operation of the high-energy pulse generator 10, the liquid column 28 is under sufficient pressure to press the punch 19 down against the powdery material 20 and precompact it, while the piston 26 is pressed up against an annular stop shoulder 46. The piston 26 carries an impact-absorbing surface 48, which faces upwards towards a bore 50 of an acceleration cylinder 52 which receives a piston mass 5 ¹ * to be accelerated, which is held at the other end of the bore 50. The surface 48 is protected by a thin layer 55 of vacuum oil or the like in order to prevent damage to the piston mass 5k and the piston 26,

Because of the high pressure of the liquid column 26, the high Vacuum in the die chamber 36 and the operational vacuum

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of the bore 50 are between the corresponding pistons 26 and 30 and the hammer bore 24 gas-tight piston ring seals 56 and 57 are arranged. These seals 56 and 57 interfere the transmission of the high-energy impulses to the material to be processed does not.

The pulse generator 16 includes means 60 sets the sudden release of fluid under high pressure gas, which "is called air cannon ^M (air-gun) 60th The" also known as "air gun ¹¹ 60 High pressure gas suddenly through its outlet ports 62 communicating with a chamber 64 that extends above the piston mass 54. The high pressure gas is supplied from a high pressure source 66. This high pressure source 66 may include a high pressure air compressor, a receiver, a pressure regulator and a filter The pressure source 66 is connected to the ^M air gun "60" via a supply line 67. This air gun ^w "60 is a device for sudden release of gas under high pressure with explosion-like speed, as more fully described in connection with Figure 15 of US Patent 3,379,273. |

is described. A signal to release the gas is from an electrical control device 68 through an electrical Cable 69 is routed to a solenoid operated valve 70 that prevents the sudden release of the powerful gas pressure the "air gun" 60 through its outlet openings 62.

The chamber 64 is designed with the smallest possible volume and is filled with a liquid, such as light oil along, so that the pressurization of the chamber is achieved 64 by the ^w air gun ^M 60 with substantial retention of the pressure prevailing in pressure to the piston mass 54

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the bore 50 in the direction of the double piston hammer device 16 speed up.

The piston mass 54 is significant in weight and is initially held at the end of the bore 50 by a locking retaining device 72 which loaded a hydraulically Has cam roller having a locking groove 71 in one of the Piston holding rod 73 contacts, which has a conical Has shaft 70 on piston mass 54. Holding piston 72 are slidably received in hydraulic cylinder guides 74 and are hydraulically mounted on the piston support rod 73 by means of a spring-loaded hydraulic accumulator 75 pressed, which via the hydraulic lines 76, 77 and 78 is connected. The hydraulically loaded holding devices 72 with cam roller locking are by a solenoid-operated valve 79 released, which is controlled by the control device 68 via an electrical cable 81.

A gas outlet port 80 of the chamber 64 is through a suitable one Pipe 83 connected to a solenoid operated outlet valve 82 and a solenoid operated accumulator valve 84. The valve 82 allows the escape of gas from the chamber 64 to the environment through a separator 84 to separate the gas from the oil used to fill chamber 64. The oil is returned to chamber 64 through line 85 and the gas is exhausted through an outlet 86 to the atmosphere. The valve 84 controls the flow of gas to a storage container 88, which is designed so that it can be brought to the pressure that the gas pressure in the Chamber 64 corresponds to after the piston mass 54 hits the double piston hammer device 18 Has.

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A solenoid controlled valve 90 is inserted into a line 92, which the gas storage tank 88 bits the bottom of the Piston mass 54 connects when the latter is on the twin piston hammer device 18 rests.

An evacuation pump 94 for the cylinder bore is connected to the via a solenoid-controlled valve 96 and a line 98 Bore 50 in operative connection. This pump 94 evacuates the bore 50 to a very low pressure, so that the kinetic Energy of the accelerated piston mass 54 essentially can be consumed when the piston hits the surface 48 of the upper piston 26 of the double piston device 18 beats.

The electrical controller 68 is provided with the timer circuitry and switches which, in suitable sequence, energize the various solenoid operated valves and relays (not shown) which control the pumps and control the actuation of the ^M airbag "60.

When the device 10 is operated for processing material by means of high-energy pulses, the piston mass 54 is in the Arranged holding position shown and the acceleration bore 50 is evacuated by the pump 94.

The powdery material to be processed is first chemically cleaned and then under a chemically pure inert atmosphere, such as helium or nitrogen held so that its individual particles have carefully cleaned surfaces that are calibrated under the compaction connect the device 10 and are cold carbonized together.

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The large piston 13 and the platen 11 of the heavy press 12 are guided along the vertical guide columns 99 of the press 12 lowered to reveal the die cavity 22, and a measured amount of the pure powdery! Material is placed in cavity 22, maintaining an inert atmosphere. "Then the press is operated to remove the Die 14 to lift the seals 44 of the hammer cylinder 25 to touch and to close the chamber 36 gas-tight and tight.

The high vacuum pump 37 is then actuated and reduces the Pressure in the chamber 36 quickly to the desired, very low operating pressure range. At the same time, the cavity 22 evacuated and shortly thereafter the liquid column 28 is pressurized, causing the piston 26 against the annular Stop surface 46 is pressed and the punch 19 compresses the powder 20. This pre-compression of the powder 20 is continued until an optimal pre-compression is achieved becomes, as it was previously determined for the particular type of powdered material 20 to be processed. if the desired pre-compression is achieved, it is maintained. At this time, the double piston hammer device 18 is effectively and completely brought into the rigid state and thus for the transmission of a high-energy pulse from the piston mass 54 prepared for the powdery material 20. the The upper plate 100 of the press 12 is attached to the guide pillars 99 set by means of large screw connections 101 that hold several removable spacers 102 that the plate 10 against Press locking rings 103 down.

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The "air gun" 60 is then actuated and suddenly delivers an amount of gas under high pressure, for example on the order of 70 to 700 kg / cm (100 to 10 000 pounds per square inch) j the gas enters the chamber 64 just after the Holding devices 72 have released their clamping of the holding rod 73 of the piston mass 5k .

The piston mass 54 is now driven in the direction of the double piston f hammer device 18 under the force of the pressurized gas in the chamber 6k. The piston mass 5k reaches a high speed, and strikes the layer 55 of protective, insensitive to impacts oil on the surface 48 of the piston 26. The stroke of the piston mass 5k sets a high energy pulse to the hammer device freely transmitting this pulse to the male die 19 . The stamping die 19 then compresses the powdery material 20 so strongly and in such a short time that the powder particles are connected to one another and form a dense, compact, precisely shaped part.

At this point in time, the piston mass 5k has come to rest on the surface 48 ', and the pressure in the chamber 64 and in the section of the bore 50 above the piston mass 5k remains at a certain value. The valve 84 is opened and the container 88 is pressurized by the gas in the chamber and in the bore 50. The valve 84 is then closed and the valves 82 and 90 are opened. The pressure in the liquid column 28 is reduced to lower the piston 26 sufficiently to allow the gas from line 92 to raise the piston mass 54 back to its initial holding position shown. When the piston mass 54 is in its initial

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borrowed holding position is raised, the excess Gas in the channel 64 through the opening 80, the line 83, the valve 82, the oil-gas separator 84 and its outlet port are passed to the atmosphere.

The large piston 13 and the plate 11 of the press 12 verden now lowered to also lower the die 14 to allow removal of the molded part from the die cavity 22 · A push rod 97 is used to remove the molded part from the die. Then one will new charge of powdery material introduced into the die cavity 22 and another part can after methods described are shaped.

In Fig. 3 is a part of an apparatus for processing Material shown using high energy pulses which is similar to the apparatus of Figure 1, but is for transfer molding a precut block of material 120 into a cavity 122 of a lower die 114 suitable. In operation of this device, an inert atmosphere is introduced through line 38 and port 40, so that all traces of the atmosphere in the die chamber 36 and die cavity 122 are flushed out. The liquid column 28 is preferably biased to a pressure value which is slightly below the value required for the flow of the warm or cold material 120 into the cavity 122 necessary is. The stroke of the piston mass 54 (see Fig. L) the double piston hammer device 18 then pushes the material 120 into the die cavity 122.

FIG. 4 shows a section of a device for reshaping material by means of high-energy pulses similar to that in FIG

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1 and 2, but this is suitable for forging a material 120. With this device a piston 30 is provided with a threaded bore 32 for receiving a forging die 132 with a concave Die surface 134 brought into pressing contact with the material 130 to be forged. The bottom of the material 130 is also forged into a shape,

determined by a cavity 136 in a die 138 %

is that on the lower plate 11 of the heavy press * 12 rests.

If desired, the chamber 36 can be opened through the opening 40 and line 38 can be evacuated or an inert atmosphere can be introduced into the chamber. the Seals 44 create a gas-tight seal in the chamber 36 when the press 12 hits the die 14, 114 or 138 presses up against the seals 44, which are arranged in the lower edge of the hammer cylinder 25.

The connections from the electrical control device 68 A to the devices to be controlled are indicated in FIG. 1 by the letters V, W ₁ X, Y, Z.

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Claims (1)

- 14 claims 1.) Method for machining material by means of high-energy impulses, whereby the material to be machined is brought into the working position between a first and a second die, characterized by the following process steps: A pretensioning force is applied that moves the dies towards each other presses and thereby exerts a pre-compressing force on the material between the dies f a massive piston is accelerated along a cylinder in a direction that corresponds to the first and second gear. vertically aligned, the massive piston effectively strikes the first die and drives the first die against the second die Apply a high-energy pulse to machine the material between the dies. 2. The method according to claim 1, characterized in that a region surrounding the material to be processed is sealed and a controlled atmosphere in this area will be produced. 3. The method according to claim 2, characterized in that the controlled atmosphere is a sub-atmospheric pressure Has lowered gas pressure. 4. The method according to claim 2, characterized in that the controlled atmosphere is an inert gas. ^ BAD ORtOfNAL 10 0 8 17/1104 5. The method according to claim 3, characterized in that the material to be processed is a powder. 6. The method according to claim 5 »characterized in that the pre-compressing force applied to the material creates a pressure between the powder particles which brings them tightly into a connecting state, and that the subsequent high-energy pulse the Powder particles connect. 7. Device for forming a material using a sudden high-energy pulse of an accelerated one Piston mass, which is moved in a cylinder and marked with a hammer, which the piston mass strikes by a double piston hammer device (18) with a first piston (16) which accelerates the impact force of the Piston mass (54t) receives, with a second piston (30), on which a die (19 _v or 132) can be attached, which is in working contact with the material to be machined (20, 120, 132), a solid and rigid cylinder (25) t surrounding the first and second pistons, a j means (45, 47) for supplying and biasing a "substantially incompressible fluid (28)" in the solid and rigid cylinder (25) between the first and second pistons to create a rigid hammer device (18) transmitting the impact wherein the biasing of the liquid (28) causes a precompression of the material to be processed by the die (19 or 132). BATH ORIGINAL 1 09837/1104 8 * Device for carrying out the method according to claim 1, characterized in that the second piston (.30) is provided with a connecting device (32), that a die part (19) is held by the connecting device, that a second die (ih or 114) has a die cavity (22 or 122) for receiving the material to be machined, that the die part (19) extends into the die cavity and has a die area which is significantly smaller than the area of the second piston (30) onto which the pressurized liquid (28) acts so that an increased machining pressure for the material can be exerted on the material to be machined through the die part (19). 9. The device according to claim 7 »characterized in that sealing devices (hk) are provided to seal the area surrounding the die, and a pump device (37) for evacuating this area. 10. Apparatus according to claim 7, characterized in that a stop device (V (>) is provided, which the First piston (26) touches the first piston against the pressure exerted by the pressurized liquid (28) Hold strength. 11. The device according to claim 7, characterized in that a support rod (73) is provided on the piston mass that the support rod extends in a direction away from the Double piston hammer device (18) extends, and that releasable holding devices (72) with the holding rod in Intervention can occur to the piston mass in its starting position in the ZyI index 711 fetched. BAD ORJGtNAL i Π 9 Π Ί 7/1 1 0 Λ Blank page