US3890824A

US3890824A - Implosion jack

Info

Publication number: US3890824A
Application number: US303057A
Authority: US
Inventors: Jean Camion; Etienne Campot; Jean Conneau; Serge Contival; Andre Dejoux; Jean Detton; Maurice Gournelle; Antoine Traimond
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-11-05
Filing date: 1972-11-02
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24
Also published as: FR2158137B1; FR2158137A1; GB1415866A; DE2253910A1

Abstract

A force producing device that has a piston movable within a chamber. As the piston is at a first position in the chamber, the chamber is evacuated on both sides of the piston by a vacuum source. The chamber, on one side of the piston, is disconnected from the vacuum source and connected to a source of fluid under pressure for moving the piston toward a second position in the chamber. A striker connected to the piston then imparts a force upon a mass located externally of the chamber.

Description

United States Patent [191 Camion et al.

[ June 24, 1975 1 IMPLOSION JACK [76] Inventors: Jean Camion, demeurant 43, carnot,

' Nogent; Etienne Campot,

demeurant 6, avenue de brimont, Chatou; Jean Conneau, demeurant 58 Bd. Voltaire, Paris; Serge Contival, 253 Ed. Gabirel Peri, Noisy-Le-Sec; Andre Dejoux, demeurant 15, rue Lakanal; Jean Detton, demeurant 80 rue Taitbout, both of Paris; Maurice Gournelle, demeurant 1 rue des Bruyeres, Asnieres; Antoine Traimond, 7 rue Jean Ferrandi, Paris, all of France 22 Filed: Nov. 2, 1972 21 Appl. No.: 303,057

[30] Foreign Application Priority Data Nov. 5, 1971 France 71.39699 [52] US. Cl. 72/453 [51] Int. Cl B2lj 7/20 [58] Field of Search 72/453, 407, 437, 436;

[56] References Cited UNITED STATES PATENTS 3,178,497 4/1965 Mosciki 425/437 3,187,548 6/1965 Murek 72/453 3,323,346 6/1967 Spangler 72/453 3,470,284 9/1969 Hartmann i 425/437 3,692,456 9/1972 Foster 425/412 3,734,008 5/1973 Akerberg 100/269 R Primary Examiner-C. W. Lanham Assistant Examiner-Gene P. Crosby Attorney, Agent, or F irmLane, Aitken, Dunner & Ziems [57] ABSTRACT A force producing device that has a piston movable within a chamber. As the piston is at a first position in the chamber, the chamber is evacuated on both sides of the piston" by a vacuum source. The chamber, on one side of the piston, is disconnected from the vacuum source and connected to a source of fluid under pressure for moving the piston toward a second position in the chamber. A striker connected to the piston then imparts a force upon a mass located externally of the chamber.

14 Claims, 7 Drawing Figures JUN24I975 3.880.824 PATENTEI] SHEET 2 PATENTEDJUN24 ms 3 0 8 4 SHEET 3 PATENTEI] JUN 24 I975 SHEET IMPLOSION JACK BACKGROUND OF THE INVENTION This invention relates to an implosion jack whose main object is to obtain very high instantaneous pressures in the form of shocks. Another purpose of the invention is to provide a means for the very rapid linear displacement of mechanical elements at speeds from l-3OO m/sec. The invention also has the objective of furnishing a simple means for making machines with rapid shocks and covering the entire range of industrially utilizable power.

Known devices for the production of very high pressures employ energy from explosives in order to create shock waves which act on the materials to be worked. There is however no direct dynamic impact upon the material. These devices are not really repetitive and their use is complicated. They do not make it possible easily to attain very high pressures; they are very expensive to employ and they require very long preparation times which precludes their industrial use.

The highest pressures presently envisaged are on the order of 2-5 Mbar.

The known devices for the linear displacement of a member by means of a jack hardly exceed a speed of m/sec. To attain the highest speeds, the devices used at this time are very complicated. As far as present shock machines using a fluid motor are concerned, these devices are such that they do not easily make it possible to obtain large impact efforts nor rapid rates of operation.

The present invention in particular has the objective of avoiding these inconveniences through simplicity of design, through the energy used, which is the pressure of a fluid associated with a vacuum. Air at atmospheric pressure, for example, is a practically constant energy on sea level which is always available and which does not cost anything. With regard to the vacuum, its obtention is well known. Vacuum pumps are relatively silent and the power and flow rates necessary to create a vacuum in the jacks according to the invention are perfectly compatible.

The present invention is an improvement of the invention by Mr. Maurice Gournelle covered by the patent application filed in France on Sept. 8, 1970.

Another purpose of the invention is considerably to increase the performances of apparatuses of this type and, by virtue of this fact, to extend their use to other fields.

SUMMARY OF THE INVENTION The principle of this jack is based on the use of the vacuum associated with atmospheric pressure. In effect, a vacuum forced into one of the compartments of the jack, while the other one is subjected to atmospheric pressure or to the pressure of a pressurized gas, which can go as high as 150 bars or more (pressure of nitrogen), makes it possible to attain very high movement speeds for the mobile parts of the jack. This speed is communicated by the expansion of the air or the gas which is compressed in the vacuum. It is evident that the more the gas is compressed, the bigger the expansion effect will be at the moment we unlock the system that keeps the mobile parts in place and the faster will be the speed obtained for a small distance through which said mobile parts move. The vacuum necessary is on the order of 10 mm Hg. When the motor fluid is at atmospheric pressure, in order to obtain fast speed it is necessary to have the mobile parts move through a longer distance, because the faster speed we want, the longer the run would have to be (2-3 m).

Atmospheric pressure is best because it does not require any particular devices for its utilization except that we have to provide the jack with cross sectional dimensions which will have to be bigger than when we use compressed gas, which is less with regard to the power it enables us to obtain.

A basic mechanical review will give us a better idea of the kinetic energy furnished by the invention. The formula W =MV /2 gives us the instantaneous force at the moment of percussion which depends on the surface of the piston in terms of cm and on the kinetic energy accumulated by the moving equipment parts under the action of expansion or entry of gas into the vacuum.

This formula seems to us insufficient in the present case because, to the weight of the mobile equipment of the jack, we must add the thrust due to the pressure of the compressed gas upon the piston at the moment of unlocking which is increased by an effect comparable to that of a blow from a ram.

Approximately speaking, we can say that the energy of such a system grows with the square of the speed. The speed is-a function of the nature of the vacuum: the more powerful the latter is, the greater the speed can be, considering the associated pressure. The more the gas is compressed, the greater the expansion effect will be and this will impart great speed to the moving components.

The parameters taken into consideration here to obtain the maximum shock effect are:

1 The most forceful vacuum possible,

2 The most compressed gas possible,

3 The largest possible piston surface,

4 The longest possible piston run in order to increase the acceleration,

5 The least possible friction among joints.

According to another version of the invention, for the same cylinder surface we can multiply its energy by setting up several pistons in series, each having its own isolated compartment.

Another version of the invention is intended to double its energy and includes arranging two jacks according to the invention opposite each other. When the locking devices of each one of them are released at the same time, their mobile equipment parts and particularly their striking mass, attached to the end of their rod, will simultaneously strike on each side of the material to be worked, for example, in cataclysm involving shock. Thus, the entire energy of the system is used.

Another version of the invention, intended to multiply its energy, consists in arranging two multiple-stage jacks, for example, opposite each other, as before.

Another version of the invention intended to increase its energy includes providing for cooperation between several simple jacks or jacks in series, three, for example, by connecting their rods to an assembly intended to add up their efforts or to arrange two series of three simple or tiered jacks, opposite each other, as mentioned above.

Another version of the invention applicable to fields covered by present impact machines involves an arrangement permitting a fast cadence and includes having the rod come out on each side of the jack, with two 3 locking positions, that is, incoming and outgoing. The double-action apparatus enables us to set up two work stations.

For single-action use, we can-in order to return the piston to the resting position-use either a small depression or we can use air compressed in the conventional fashion, or we can use a electromechanical or other return.

The technology of such apparatuses requires very special attention because of the efforts involved. As a matter of fact, in the case of very high-power apparatuses, at the moment of impact by the striking mass against the piece to be worked, the inertia of the mobile equipment parts of the jack tends to make it continue with its displacement, which is normally expressed by a deformation of the assembly used for the attachment of the piston to the rod.

Another arrangement includes ribbing the piston in such a way that it will be practically undeformable. The rod itself is reinforced by a bracing tube designed so as to be able to resist buckling. The active end of the rod has an intermediate piece which is intended to receive the hammering efforts. It is treated as a wear-and-tear piece.

BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of this invention will emerge from the following description and will give us a better understanding through several examples of implementing the device, referring to the attached drawings where:

FIG. 1 is a front view partially in section of a highpower jack,

FIG. 2 is a diagrammatic view showing distribution of fluids in the jack,

FIG. 3 is a front view partially in section showing an embodiment of the jack operated by shock catalysis,

FIG. 4 is a front view partially in section showing an embodiment where the jack has several stages, in series,

FIG. 5 is a top view of the multistage jack and the arrangement of tie rods shown in FIG. 4,

FIG. 6 represents an assembly of single-cylinderjacks or multistage jacks arranged in parallel,

FIG. 7 represents the front view of the assembly shown in FIG. 6.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT FIG. 1 shows a longitudinal partly cross-section view of a high-power jack. It has cylinder 1, forward bottle 2, rear bottle 3, tie rods 4, piston 5, and sealing joints on 6, 7 and 8 the cylinder, piston and piston rod, respectively. The moving parts are piston 5, rod 9 made of silicomanganese steel (for example, 45-88), shouldered at 10 to receive the piston 5 which is made in one piece with rod 9 by means of a washer 10 and a series of screws 11.

Piston 5 is made of molded duraluminum; it has a series of eight ribs 12 to make it practically undeformable at the moment of impact. The carrying joints 7 of piston 5 can be made of graphite-treated rilsan and the sealing joints of the I-Iuhn or Riwgter type, well known to the expert, are preferably arranged between the carrying joints. The bore of cylinder 1 as well as ring 13 are made of hard steel, and rod 9 will be treated with Tenifer. A scraping joint 14 prevents foreign bodies from getting into the cylinder.

On the nose ofjack 15 there is attached the striking mass 16 made, for example, of 35NC15 steel, involving a groove 17 intended to lock-by means of the turning key 18, supported by bearing 19, which is in one piece with forward bottle 2the hammering

washers

20 and 21.

Turning key 18 is moved by an electromagnet with appropriate dimensions and force (not shown) or by any other mechanical means.

This type of jack will preferably be arranged vertically in order to reduce the friction of the sealing joints under the action of the weight of the mobile equipment. Due to the operating principle, key 18 will have to support only the weight of the mobile equipment portions and possibly the differential pressure between

chambers

22 and 23.

The tie rods are attached to the bottles in a manner identical to the jack rod by means of plates such as at 10 and a series of screws 11.

FIG. 2 shows the diagram for the distribution of fluids in the jack. The chamber 22 of the jack has an opening 24 out of which comes a pipe for the admission of atmospheric pressure which is taken at 29 in the filtering container 28 (which has a large volume so as to avoid charge losses due to the filter) and involving electric valves Vatl. Out of opening 25 comes a tube which leads to the balloon in which prevails vacuum 30. Communication with the vacuum is controlled by electrovalve Vvl. A pressure gauge controls the level of rarefaction of the air in chamber 22. Opening 26 is connected by a pipe to a balloon in which a vacuum prevails. Communication between this balloon and chamber 23 is controlled by electrovalve Vv2. Opening 27, situated inside filtering container 28, is connected to the electric valve for the admission of atmospheric pressure Vat2 which has a very large capacity so that the admission of atmospheric pressure or of a compressed gas will not be braked.

As described here, this jack operates as follows: the strike order is given when the following conditions are met: the moving equipment portions are locked at high neutral gear by key 18. Vatl and Vat2 are closed. Vvl and Vv2 are open,

chambers

22 and 23 are under a vacuum; M gives its permission (when predetermined rarefaction has been attained). At this moment, the strike order is possible. This order is given by operating key 18, for example, automatically, by means of an electromagnet. At the end of the movement of key 18, an electrical passage contact closes Vv2; at the end of the movement and simultaneously the piston is unlocked and a second contact opens Vat2 through which air, at atmospheric pressure, rushes at very great speed into the vacuum of chamber 23 and hits the piston, causing it to move all the more faster because a strong vacuum is created in chamber 22.

The return of the mobile equipment to high neutral gear, where it is automatically locked, can be achieved through the combined and simultaneous action of closing Vvl and Vat2 and opening Vatl and Vv2. The vacuum is created in chamber 23 and the atmospheric pressure, admitted into chamber 22 at 24, slowly pushes the piston back toward its locking position.

At the moment of locking, Vatl is closed and Vvl is opened, providing communication between chamber 22 and balloon 30 where the vacuum is created by pump 31.

This arrangement enables us to prevent the locking device from having to supportthe entire static load due to the atmospheric thrust, in other words, tons for a jack with a surface of l m Moreover, chamber 23 1 is very small and atmospheric pressure is established in a very short time.

For the jacks which are to accomplish the displacement of members at very high speed, it may be necessary to control that speed and especially the acceleration. Upon starting, electrovalve Vatl may have a diaphragm and may be servocontrolled by the displacement of the rod so as progressively to admit atmospheric pressure.

FIG. 3 shows an arrangement of a jack for the application of cataclysm by shock. It is connected to a crater or mixing'bowl dieplate 32 by means of columns 33 which are attached, on the one hand, to the forward bottle 2 of the jack by means of a shoulder, a washer 34, and a series of screws 35, and, on the other hand, on dieplate 32 by means of centering device 36, the shoulder 37 and the screws 38. Dieplate 32 supports an intermediate striking block similar to'the column block sliding on columns 40 and attached to dieplate 32, by means of hard steel rings 41, treated with Tenifer. Plate 39, which is as light and as rigid as possible, carries striking piece 42 which is centered and attached by a series of screws 43. The moving part of the intermediate striking tool is raised after each operation by a series of hydraulic jacks. It is kept at high neutral gear (PMI-I) by a very light spring locking device whose only purpose is to keep it at PMH while the lifting jacks, not shown, are moved away.

The crater dieplate 32 has a crucible 44 in which the material to be worked is placed. This crucible itself is arranged in a kind of movable basin 45 attached to the dieplate by means of screws 46. The bottom of piece 45 is equipped with an extraction foot in order to extract crucible 44 from basin 45 after the treatment of the material. All of these elements are carefully adjusted. However, in order to catch any possible defects, a hydraulic pressure of about 1 t/cm obtained by power multiplier, is directed through channel 49; it can also serve for the extraction of basin 45. Tightness is guaranteed by special joints 47 and 50. A connected chamber 51, not shown, is provided for working in a vacuum. A space (1 between the material to be worked and piece 42 is possible.

To remove the crucible (which can be loaded in the laboratory) and to replace it with another one, the opening jacks release the tool 42 at the height necessary for extraction and for the replacement of crucible 44 and basin 45. Tool 42 is then lowered again and locked in place for a new operation.

The mobile equipment of the jack as well as that of the striking tool are free at the moment of impact and columns 33 therefore have to support only the weight of the assembly with good geometric corrections (limiting the bending and buckling). The crater dieplate is arranged on a hard-steel support plate 52 which itself floats on lead or is anchored on a massive piece of concrete with very great inertia and resting on a bed of sand so as to absorb the vibrations due to the shocks.

FIG. 4 shows an arrangement of a jack with several stages in series. It involves a succession of cylinders 1 which are attached to intermediate bottles 53 by means 6 .of tie rods 4 arranged according to FIG. 5, that is to say, the first cylinder is attached to the bottles by tie rods arranged at l and the second one by tie rods arranged at 2, the third one by tie rods arranged at 1, and so forth. The moving equipment is made up of a rod 54,

. similar to rod 9, except that the shoulder 10 is prolonged over the entire length of the rod on which are arranged as many pistons as there are stages. The pistons are kept spaced by braces 55 and hammering washers 21. They are assembled as in FIG. I by a washer 11 and screws 10.

The distribution of fluids for each of the n cylinders is identical to that in FIG. 2, and all of the outputs 24, outputs 25, outputs 26, and outputs 27 are in series so as to guarantee simultaneous functioning between common chambers with n stages. The operation is the same here.

FIGS. 6 and 7 show an assembly of three singlecylinder or multi-cylinder jacks arranged parallel. The three or n cylinders of the jack are tightened between

bottles

56 and 57 by tie rods 4 identical to those in FIG. 1 and arranged according to FIG. 7. The three jack rods are assembled on a block 58 which has a triangular shape by means of a shoulder 59, washer 60, and screws 61; the striking nose 62 is centered and attached on block 58. Locking is obtained by the turning key 18 which turns in block 19 and moves as provided for in the example in FIG. 1.

This assembly operates in a manner similar to the one described in FIG. 2. The feed devices for these same chambers are arranged in series. A filtering tank 28 encloses the three jacks and its volume is a function of their cylinders without causing any charge loss.

The opposite arrangement of these simple or series jacks makes it possible to multiply the energy of the shock. The jacks in this case are arranged along a horizontal line and their mobile masses must be rigorously identical. The same chambers are connected in series to the same pipelines for conducting the atmospheric pressure and for communication with the vacuum. The crater die plate is mounted in a floating fashion and in one piece with two intermediate striking tools each having its own opening mechanism involving connected hydraulic jacks. When the runs of the jacks are longer, the jacks have a forward guard so as to compensate for any possible gaps in the displacement speed of jacks arranged opposite each other. The unlocking order is simultaneous for the two assemblies and is given by means of a common set of rods regulated with great precision. The floating die plate moves slightly if one of the striking noses is reached by a jack advancing forward of the other, and the slowdown following this enables the second jack to compensate for its delay.

The device involved in this invention may be used primarily for catalysis by means of shock and for very high-energy shock machines. It can also be used advantageously to obtain fast moving speeds.

We claim:

1. A force-producing device comprising a chamber, a piston movable between first and second positions in the chamber, transmitting means connected to the piston for transmitting force generated by the piston moving between the first and second positions, vacuum means connected to the chamber on both sides of the piston for evacuating fluid from the chamber, fluid means connected to the chamber on both sides of the piston for introducing fluid into the chamber, valve means associated with the vacuum and fluid means for selectively communicating the vacuum and fluid means with the chamber on each side of the piston.

2. The device in claim 1, and further including lock means for preventing the piston from moving from the first position when the locking means is in its locking position.

3. The device in claim 1, wherein the vacuum means includes a single vacuum source connected to the chamber on both sides of the piston.

4. The device in claim 1, wherein the vacuum means is capable of maintaining a negative pressure of at least 1 mm Hg in the chamber.

5. The device in claim 1, wherein the fluid means communicates the chamber with the atmosphere when the valve means associated therewith is in a selected position.

6. The device in claim 1, wherein a plurality of chambers and pistons are provided, all of the pistons being connected to the transmitting means, the vacuum means and fluid means being connected to communicate simultaneously with all of the chambers.

7. The device in claim 6, wherein the chambers and pistons are arranged in parallel.

8. The device in claim 6, wherein the chambers and pistons are arranged in series.

9. The device in claim 1, and further including a stationary body including a crater therein, a crucible associated with the crucible for applying a counterpressure to' the crucible on the side opposite the transmitting means.

II. The device in claim 10, wherein the pressure means is capable of applying a pressure of at least about 1 t/cm 12. The device in claim 1, wherein the piston is in the first position when the vacuum means communicates with the chamber on both sides of the piston, and the piston will be forced to move toward the second position when a predetermined negative pressure is reached in the chamber on one side of the piston and communication between the vacuum means and the chamber on the other side of the piston is stopped and the chamber on said other side of the piston is communicated with the fluid means.

13. The device in claim 12, wherein the piston will automatically move from the second position to the first position when communication between the fluid means and the chamber on said other side of the piston is stopped and the chamber on said other side of the piston is communicated with the vacuum means, and at the same time communication of the chamber on said one side of the piston with the vacuum means is stopped and the chamber on said one side of the piston is communicated with the fluid means.

14. The device in claim 12, and further including lock means for preventing the piston from moving when the lock means is in its locking position, the piston being capable of moving toward the second position when the lock means is out of its locking position. =l

Claims

9. The device in claim 1, and further including a stationary body including a crater therein, a crucible spaced from and aligned to be in the path of travel of the transmitting means and adapted to fit in the crater for holding material to which force is to be applied by the transmitting means.

10. The device in claim 9, wherein pressure means is associated with the crucible for applying a counterpressure to the crucible on the side opposite the transmitting means.

11. The device in claim 10, wherein the pressure means is capable of applying a pressure of at least about 1 t/cm2.

12. The device in claim 1, wherein the piston is in the first position when the vacuum means communicates with the chamber on both sides of the piston, and the piston will be forced to move toward the second position when a predetermined negative pressure is reached in the chamber on one side of the piston and communication between the vacuum means and the chamber on the other side of the piston is stopped and the chamber on said other side of the piston is communicated with the fluid means.

14. The device in claim 12, and further including lock means for preventing the piston from moving when the lock means is in its locking position, the piston being capable of moving toward the second position when the lock means is out of its locking position.