US3169273A

US3169273A - Pressure-multiplying apparatus

Info

Publication number: US3169273A
Application number: US253326A
Authority: US
Inventors: Brayman Jacob
Original assignee: Barogenics Inc
Current assignee: Barogenics Inc
Priority date: 1963-01-23
Filing date: 1963-01-23
Publication date: 1965-02-16
Anticipated expiration: 1982-02-16
Also published as: SE219137C1; GB988179A

Description

Feb. 16, 1965 J. BRAYMAN 3,169,273

PRESSURE-MULTIPLYING APPARATUS Filed Jan. 25, 1963 INVENTOR. I J JACOB BRAYMAN his ATTORNEYS United States Patent Office Zhldhiid l atented Feb. E6, 1965 3,169,273 PRESSURE-MULTELYHNG APE ARATUS acct: Brayrnan, Staten island, Nfti, assignor to Baregenics, inc New York, N.it., a corporation of New York Filed Ban. 23, 1963, Ser. No. 253,326 7 Claims. (Cl. 18-16) This invention relates to pressure apparatus in which an object is compressed by an array of pressuremultiplying anvils disposed in three dimensions about the object. More particularly, this invention relates to improvements in pressure apparatus of such sort wherein the compression of the object takes place asymmetrically in the sense that the anvil forces on the object are a mixture of one or more active forces and one or more reactive forces induced by the active force or forces.

An apparatus for so compressing an object asymmetrically is disclosed in the article Compact Multi-Anvil Wedge-Type High Pressure Apparatus on pages 5964 of the August 15, 1959 issue of the Journal of Research of the National Bureau of Standards. That apparatus comprises an upper vertical anvil and three lower anvils disposed in a tetrahedral configuration about a tetrahedral object such that each of the four anvils bears by its front face against a respective one of the four faces of the object. The rear face of the upper anvil abuts against the underneath of a movable upper platen of a conventional two-platen press.

Disposed on the lower stationary platen of such press in coaxial relation with the upper anvil is a hollow sleeve having an inner wall which is conically tapered to progressively reduce the inner diameter of the sleeve in the downward direction. The sleeve supports the three lower anvils by virtue of a bearing of the rear faces of those anvils against the inner conically tapered wall. Such wall has a slope steeper than that which would be required to produce a right angle relation between the wall and the axes of the lower anvils.

The mentioned object is comprised of a body of material to be subjected to pressure and of a tetrahedral casing for that body, the casing being constituted of a pressure-transmissive material such as pyrophyllite.

In operation, the movable upper platen of the press is advanced towards the stationary lower platen to drive the upper anvil downwardly. That downward driving causes the tetrahedral object to exert on each of the lower anvils a force transmitted to the comically-tapered inner sleeve Wall against which the rear face of the lower anvil bears. Since such wall has a slope which is steeper than that which would render the wall exactly normal to the axes of the lower anvils, those anvils respond to the load thereon by sliding down along the wall. As the lower anvils so slide, the taper of the wall reacts like a wedge to advance the three lower anvils towards the center of the object simultaneously with the advancement then taking place of the upper anvils towards this same center. Hence, pressure is applied to the object in an active manner by the upper anvil and in a reactive manner by the three lower anvils. The applied pressure creates in the casing material of the object a pressure field which acts upon the central body of material in the object to subject that body to high pressure.

It might be noted that various types of apparatus which use the same wedging effect to compress an object are disclosed in co-pending application Serial No. 833,809, filed August 13, 1959, issued as Patent No. 3,105,994 for Pressure Apparatus and owned by the assignee of this application.

The apparatus described in the article is restricted to smaller ratings and is otherwise limited in application because of an inherent inability of its anvils to act uniformly on the central object. Specifically, while no shear stress is produced on or in the object by the upper anvil, the friction between the sleeve Wall and the rear faces of the lower anvils does develop a shear stress between the front face of each such anvil and the face contacted thereby of the object. Further, because the slope of the conicallytapered sleeve wall isnecessarily steeper than that which would render the wall normal to the axes of the lower anvils, the reactive force exerted by the wall on each lower anvil is not in line with the axis of that anvil. Still further, because the lower anvils load the sleeve to produce an outward deformation of its wall at the places against which those anvils bear, the lower anvils do not advance as far as does the upper anvil towards the center of the object being compressed. Because of all the factors just mentioned, the apparatus which has been described is incapable of producing in the pressure transmissive casing of the object a hydrostatic pressure field which is truly uniform.

It is accordingly an object of this invention to provide apparatus which is free of the above noted disadvantages.

Another object of this invention is to provide apparatus in which an object is subjected to a compression which is asymmetric in the sense stated but in which the compression produces a uniform hydrostatic pressure field in the casing of the object.

These and other objects are realized according to the invention by providing a plurality of pressure-multiplying anvils which are arranged in three dimensions about a central cavity operably containing the object to be compressed, and which anvils are comprised of (a) a first anvil which is stationary relative to a reference point, and (b) a group of second anvils which are movable relative to that point. Also provided is means to subject the second anvils to forces in line with the axes thereof and to produce between all of the anvils a relative movement towards each other so as to compress the object.

When the object is so compressed by a first anvil which is stationary relative to a reference point and by second anvils which are movable relative to that point, during the compression the center of the object undergoes a shift in the direction of the axis of the first anvil relative to the initial positions of the axes of ones of the second anvils. According to the invention, however, the last named ones of said second anvils are floatingly supported in a manner whereby such anvils are unconstrained in respect to movement in the direction of shift except for the friction occurring between such anvils and the object against which those anvils press. Hence, such anvils are free to be moved and are moved by that friction to follow the shift. Therefore, the initial relative alignment of the axes of all anvils is maintained constant throughout the compression of the object. Because the alignment of the anvil axes so stays constant, the anvils are adapted by that feature and others to develop a uniform hydrostatic pressure field in the casing of the object being compressed.

For a better understanding of the invention, reference is made to the following description of an exemplary embodiment thereof and to the accompanying drawings wherein:

FIGURE 1 is a side elevation in cross section of the said embodiment, the cross section being taken in a vertical plane through the axis of the embodiment; and

FIG. 2 is a graphical diagram explanatory or" the operation of the embodiment.

Referring now to FIG. 1, the reference numeral It) designates a housing of circularly annular cross section in the horizontal plane. As shown, the housing It? is mounted on a stand 11. -Formed within the housing is a hydraulic cylinder 15 having in its bottom a shallow well to of circular cross section in the horizontal plane and of adiameter smaller. than that. of the cylinder.

proper. V V 1 The upper end of cylinder is shown as being closed by a massive plug 17 inserted in the upper end of housing 10am secured to the housing by eight equiangularly spaced closure pins extending horizontal through holes 13 in the housing. to be received in holes 19 in the s ide of the plug. Of those eight pins, two pins 20 are shown. The plug and pin assembly is capped by a safety shield 22 which. precludes inadvertent removal of the pins. When access is desired to the interior of cylinder 15, the shield 22 is removed, the closure pins are drawn out of the-housing, and the plug 17 is then lifted out of the upper end of the housing. "As an aid to such lifting, eye bolts (not'shown) may be screwed into the threaded holes 23 formed in the top of the plug.

The closure means 17-22 is only one of many which can be. used. As alternatives, .the closure means may be a hinged fastenable cover or one of the closure arrangements disclosed in US. Patent 3,063,594 issued November 13, 1962 or the closure 'means disclosed in US. Patent 3,049,756'issued August 21, 1962.

Slidably received within cylinder 15 is a cylindrical piston 29 which carries in. a groove 30 at its upper end a seal ring 31 in contact with the inner wall of the cylinder. The piston may be rotatable in cylinder 15 inasmuch as in operation the piston will become automatically adjusted to the angular position which is proper therefor. At a point above the cylinder bottom the piston is decreased in diameter to form an annular shoulder 32 and a stem 33 extending downward from the shoulder to be slidably received in the well 16 of the cylinder;

' Such construction of the. piston produces in the cylinder an annular space 34 for receiving pressurized hydraulic fluid injected into-.the cylinder-through a conduit 35 and through an inlet 36 providing a threaded connection for piping from a hydraulic pump (not shown). Fluid injected into that space is obstructed from leaking from space 34 into well 16 by a seal ring 37 extending around piston stem 33 and seated in an annular groove 33 formed in the side of the cylinder. In the event any fluid does leak past seal ring 35 into well 16, pressure is prevented from building up in the well by a hole 39 through which the fluid is free to drain from the well to. the exterior of the housing 10.

The piston 29 has formed therein an upper vertical bore 45, a lower vertical bore 46, and four horizontal bores which are equiangularly spaced around the piston, and ofiwhich the

bores

47 and 48 are shown. All six bores are cylindrical bores of equal diameter, and all six bores intersect at a'central space 50 within the piston. The upper vertical bore and the four horizontal circumferential bores extend from that space all the way through the piston. 'This is not true of the lower vertical bore 46 which terminates short of the piston bottom (i.e., the bottom of piston stem 33) so as to have a wall portion 51 of the piston interposed between the lower end of such bore and the piston bottom. 7

For reasons later explained, the piston 29 is so constructed that pressurized fluid in annular space 34 acts upwardly on the piston over an effective cross sectional area (normal to the piston axis and mostly provided by thesurface of shoulder 32) which is substantially equal to the cross sectional'area of the wall portion 51 which closes oif the lower end of bore 46.

The upper bore 45 provides a passage ton to itscentral'space for an upperanvil 55 referred to hereinafter as the stationary anvil because it is operably stationary relative to the -housing'lt) taken as a reference datum for movement. The principal parts of anvil 55 are a cylindrical backup member 56 and a pressure-multiplying tool 57 mounted by conventional fastening means (not shown) on the forward end of member 56. The rear end of member 56 is secured to a mounting plate 58 having a conically tapered, downwardly-inthrough the pisplanar face.

wardly sloping, circumferential Wall which is gripped by a matching, tapered, inner circumferential wall of an annularclamp ring 59 boltediby bolts 60 to the underside of plug 17.- By so mounting anvil 55 on plug 17, the anvil has some freedom to rotate around its axis when the anvil is operably subjected to high pressure.

The tool 57 of anvil 58 is comprised of a tool head having a tapered front end and a cylindrical shank, the

latter being surrounded by a steel reinforcing ring 66.

The taper on head 65 is formed by four bevel faces of which face 67 is shown, and which render the front end of the head. in the shape of a truncated squarepyramid,

the f-r-ont face 68 of the head being accordingly a square 7 Because that front face is substantially smaller in area than the rear face of head 65, the head is adapted in a well known manner. to multiply pressure in the sense that a pressure applied to the rear face thereof will be manifested as a substanitally greater pressure exerted by the front face of the head. Because the head is used as a pressure multiplier, it isconstituted of sintered tungsten carbide or of a like material adapted to withstand without breakage the high stresses set up in the material as an incident to the pressure multiplication.

The stationary anvil 55 in bore 45 is one of an array of six anvils of which theother five are disposed in the five remaining bores of piston and are referred to hereinafter as movable anvils because they are movable relative to the reference datum provided by housing. 10. Of those five movable anvils, three are shown in FIG. 1,

I namely the anvil 7th in bore 46, the anvil 70 in bore 47 and the anvil 70 in'bore 48. Since all five movable anvils are substantially identical in structure, only the anvil 70 will be described in detail, it being understood that, unless the context otherwise requires, the description is to be taken as applying also to the other four movable anvils, and that (as among

anvils

70, 7h, 70") the same reference numerals with different prime suflixesare used to designate counterpart elements of the several anvils.

The anvil 7&9 is comprised at its forward end of a tool 77 whcih has a square planar front face 78, and which in this respect and all others is a duplicate of the earlier described tool 57 for anvil 55. The tool'77 is non-rotatably mounted by conventional fastening means (not shown) on the front end of a cylindrical ram 79 slidably received in the bore 46 and constrained from rotating therein by conventional keying means (not shown). As illustrated, the ram 79 is disposed in. the forward end of bore 46 to provide in the bore behind the ram a chamber 80 for receiving hydraulic flu-id. Such fluid may be injected into chamber 30 by way of a hole 81 extending through piston 29 between chamber 8t) and the aforementioned annular space 34. To obstruct leakage of fluid in chamber 86 past ram 79 and into the central space 56 of the piston, the ram 79 carries a sealing ring 82 in an annular groove 83 formed in the circumference of the ram.

Complementing the'fluid passage 81, there is formed the piston to permit passage of fiuid from space 34 to each of .the other three horizontal bores.

The front faces of the one stationary anvil and the five movable anvils are disposed in relation to each other to define a central cubic cavity for containing the illustrated pressure-receiving assembly 9b. That assembly is comprised of an-outer cubic casing 91 of'apressuretransmissive material (e.g. pyrophyllite) and an inner body 92 which is the material whose compression is ultimately desired, and which may be a charge for making synthetic diamonds, a workpiece to be subjected to high pressure, etc. As indicated by FIG. 1, the six planar square front faces of the six anvils each bear in centered relation against a respective one of the six outside faces 'ofcasing 91 but are somewhat smaller in size than those casing faces. Such size difference causes the six anvils to be separated from each other by inter-anvil. gaps d3 which permit relative movement between all he anvils in the direction toward each other.

The described apparatus is operated in the following manner. As a preliminary to a compressing action, the closure plug l? is removed to thereby remove upper anvil 55 from here Next, the lower vertical anvil 7d and the four horizontal anviis are adjusted to a position at which their front faces make a cubic nest having a center point on the aids of anvil 7d and or" proper size to permit a pressure-receiving assembly 93 to be slipped thereinto. The positioning of anvil 23 (which would ordinarily tend to fall of its own weight in bore as) can be accomplished through the use of a hollow tube (not shown) side perforations and having a threaded upper end received in a threaded hole in the bottom of ram so that the tube props the anvil 7i) up from the bottom of bore The distance by which the tube so holds anvil up in its here is adjustable by the procedure of (a) drawing anvil it? up through i r bore 45 to remove the anvil from piston 29, (Zr) turning the mentioned tube to vary the amount thereof threadedly engaged in the hole in the bottom of ram until the free (bottom) end of the tube is a selected distance from the ram bottom (c) reinserting the anvil 7-53 and attached tube in bore so and allowing the anvil to drop until the bottom of the tube strikes the bottom of the bore.

Inasmuch as there is some friction between the seal rings carried by the four horizontal anvils and the walls of the bores in which those anvils are received the horizontal anvils may be adjusted by a hand or by a hand tool (inserted through upper bore 45 into space 59) to positions suitable to form the mentioned nest. Alternatively auxiliary spring-actuated or hydraulically actuated devices (not shown) may be used to position the horizontal anvils (and, also, if desired, the vertical anvil 70).

Gnce the nest has been formed by the proper positioning of the front faces of the five lower anvils, a pressure-receiving assembly 96 is slipped into the cavity between those anvils. Next the upper open side of the cavity is closed by lowering the plug 17 to lower the attached stationary anvil 55 through bore 45 in piston 22? until the front face 63 of anvil 55 rests against the upper face of the assembly. The plug 17 is then anchored in place by insertion thereinto of theclosure pins 28, the safety shield 22 is slipped over the outer ends of those pins, and the apparatus is now ready to operate.

Operation is initiated by injecting pressurized hydraulic fluid through inlet 36 and conduit 35 into the annular space 34 formed in cylinder behind the annular shoulder 32 of piston 29. From that space, the pressurized fluid flows through horizontal passage 81 into chamber behind anvil 70 to drive the front face 78 of that anvil against the pressure assembly 90 and to thereby force the assembly upwards against the front face 68 of the upper stationary anvil 55. At the same time,' pressurized fluid flows from the annular space 34 through the vertical grooves leading upward therefrom (eg. grooves 81' and 31"} into the chambers at the radially outward ends of the four horizontal bores to there drive the four horizontal anvils forward in their bores so that the front faces of those anvils press against the assembly 50. in this manner, all six sides of the pressure-receiving assembly are simultaneously subjected to pressure from the front faces of the six anvils. Since the pressure of the fluid is ordinarily several thousand atmospheres and since, as described, the anvils have a pressure-multiplying effect, the pressure to which the assembly 90 is subjected is or may be on the order of many thousands of atmospheres.

In response to this great pressure, part of the pressure-transmissive material in casing 91 of assembly 90 is extruded into the inter-anvil gaps 93 to there form gaskets which hold in the pressure developed in the main body of the casing,,and which provide lateral support for the forward portions of the pressure-multiplying heads The remainder of the pressure-transmissive mate rial becomes plastic to have a hydrostatic pressure field created therein by the pressure applied thereto. Such field acts upon the central body 92 to produce thedesired result of subjecting the material of that body to super high pressure. 1

In connection with the described operation, it is to be pointed out that the apparatus uses a hydrostatic pressure field developed in a pressurized medium to drive the anvils. In so doing the apparatus follows the teachings of US. Patent 3,044,113 issued July 17, 1962 and co-pending applications owned by the assignee of this application and identified as Serial No. 112,385 filed May 24, 1961, issued as Patent No. 3,091,804 and Serial No. 112,265 filed May 24, 1961 issued as PatentNo. 3,- 093,862.

Referring now to FIG. 2, the lines a a a and [1 represent the-initial positions of the axes of, respectively, the

anvils

55, 70', 70 and 70". Those axes as initially positioned intersect at a point C which is the initial center of the pressure-receiving assembly 90. The outline of that assembly is represented by the solid line square s when the assembly is uncompressed and by the dotted line square s when the assembly is compressed.

During compression, the pressurized hydraulic fluid in chamber exerts on movable anvil 70 an upward active force Y which is in line with the anvils axis :1 and which drives assembly'9tl towards stationary anvil 55 to cause the latter anvil to subject the assembly to a downward reactive force Y; in line with the axis a; of anvil 55 and equal in value to the active force Y Thus, the pressure-receiving assembly 90 is vertically compressed by an active force from anvil 70 and by a reactive force from anvil 55.

Concurrently, the bodies of pressurized fluid in chambers 8t) and 80" produce a rightward acting force Y and a leftward acting force Y; on, respectively, the anvils 70' and 70" in the horizontal bores 47 and 48 of the piston 29. Each of the forces Y and Y is equal in value to the forces Y and Y Because the rear faces of anvils 79' and 70" on which the pressurized fluid acts are planar circular faces normal to and concentric with the axes of those anvils, the forces Y and Y; are always directly in line with the axes of the anvil 7i) and '70", respectively. The described inline relation is represented in FIG. 2 by the showing of the arrows designating the forces Y and Y as being respectively coincident with the lines a and a Because the last-named anvils are slidably received in the bores 47 and 43 of piston 29 which is maintained in constant axial alignment by housing It the Walls of those bores maintain such anvils in a constant alignment relative to each other and to the anvil 70, and, moreover, preclude angular tilting of those anvils relative to the axis a and anvil 55. Thus, the piston 29 and housing it) serve as a guide means for the

anvils

70, 70 and 70".

What has been said so far concerning horizontal anvils 70' and 70" applies also to the other two horizontal anvils which are not shown by FIG. 1. Therefore, the uncompressed assembly 90 (represented by square s) is subjected to six equal forces which are produced by the SIX anvils pressing on the assembly, and which are all active forces except for the one reactive force Y from the stationary anvil 55.

The assembly when thus compressed is deformed so that its dimensions are reduced, such reduction being, represented in FIG. 2 by the smaller size of square s than square s. Because the deformation in the vertical direction of assembly fit is produced by the squeezing 0f the assembly between two anvils of which the upper is stationary and the lower is movable, the vertical deformation produces a shifting of the center of the assembly along the axis. a of anvil 55 from the shown point C to a new point C closer to the stationary anvil 55. Thus the compression of the assembly produ ces an oflsetting of the center thereof relative to the initial positions a and m nt the axes of the-shown horizontal anvils 70' and 70", the same oifsetting occurring relative to the initial positionsof the axes of the two horizontal anvils which are notshown.

If the horizontal anvils were to beso constrained that their' axes continued/to be coincident withthe initial positions thereof, the described shifting of the center of I assembly 90 would produce an eccentric loading thereon .by the'horizontal anvils because the centerlines of action of those anvils would no longer pass through the center of the pressure-receiving assembly. 7 .As a result, the horizontal anvils would create in the pressure-transmissive casing'91 of assembly 9G a hydro- "static pressure field which would be non-uniform. As another result, the shift in the course of its deforming of the whole casing 91 towardsanvil 55 would develop on .in a manner as follows.

7, v Referring to both FIGS. land 2, when the pressurized fluid inchamber .80 exerts an upward pressure onv the cross sectional area of the rear face of, anvil '70, the

fluid also exerts a downward pressureof the same value over substantially the same cross sectional area on the wall portion 51 of piston 29 bywhich chamber SOis bounded at its lower end. Therefore, the fluid in chamber 80 urges the piston 29 downward by a fOI'C6.Y3 which is substantially equal to the upward force Y exert ed by the anvil 70 on the pressure-receiving assembly.

-If. the force Y on piston. 29 were not counteracted, that force would serve merely to drive the piston 29 downwardly in the cylinder. 15. 'It happens, however, that the downward force .Y on the piston is opposedby an upward force Y exerted on the piston in the annular space 34 within the cylinder. 15. The pressure of the fluid in that space is the same as the pressure of the fluid in chamber 80. Also, the etfectivecross sectional area of the piston against which the'fluid in space '34 acts upwardly is substantially equal to the cross sectional. area of the wall portion 51 of the piston'against which the fluid in chamber 80 acts downwardly; Therefore,

the upward force Y on the piston is substantially equal to the downward force Y thereon. Because the piston 29 is so actedupon by downwar and upward forces which are substantially equal in value, the piston is subjected to a net axial force which equal zero or is close to zero to thereby render thepiston axiallyfloating in the cylinder 15.. In other words, there is no significant constraint in the vertical direction 0 the motion of the piston-within the cylinder.

-- Inasmuch as the piston is axially floating, and inasmuch as the piston provides the only contraint in' the vertical direction for the horizontal anvils such 'as anvil "anvils 70' and "70 after the" assembly 96) has'been con1.

pressively deformed. I

The following matters with, the. showing in; FIG. 2 .of the lines a and 41 First; as stated, those liens pass through the center of the assembly when that center is at its new position C.

' Further, theequal forces Y and Y by which the anvils .70 and 70" act on assembly 99 at or towards the end 7 of compression are forces which continue to be directly and 70", those anvils are also fioatingly supported,

i.e..are uncon trained by their support (piston'29) from ,vertical movement. The only constraint on the vertical 7 movement of such anvils is the friction whichis' produc'ed by the pressure contact of thoseanvils with assembly 90, and which, in effect, couples the horizontal anvils to the assembly so as to move vertically there with. The result is that, when the center of assembly shifts, as described, from the point C to the point C, the mentioned friction causes the axesfof such anvils to follow that shift so that those axes continue to pass through the center of pressure-receiving assembly. Such a following is represented in FIG. 2 by the dotted lines a and a which illustrate the positions of the axes of in line with the axes of such anvils'when those axes are at. their. new positions a and in. Still further, because the horizontal anvils are received in: boresfin a piston which is constrained-by the wall of cylinder 15 from being tilted relative to the axis Q1 of the stationary anvil 55, the axes of the horizontal anvils when in their new positions (1 and a "c0ntinue to make the same angle with axis a as they did when in their initial positions a and a i Thus, in the described apparatus, all of the'horizontal anvils are driven inwardly against the assembly 90b;

forces which continuously act inline with the axes of such anvils while, simultaneously, those anvils are supported in a vertically unconstrained manner so that the friction contact thereof with the assembly .causesthose anvils to follow the vertical shift in the center of the assembly towards the stationary upper anvil 55. Because the horizontal anvils so follow the vertical shift in the center of assembly 9%, eccentric loading of that assem- I bly by those anvils is avoided,-wherefore the anvil pressure produces a uniform hydrostatic field in the casing 91 of the assembly. .The piston follows any vertical shift undergone by the horizontal anvils so that the upward movement of such anvils does not produce any binding of those anvils intheir bores. Because of the described construction of the apparatus, each of the anvils which bears or! assembly 9% moves equally towards the center point of the assembly when that center point is considered I as the reference point for anvil movement.

' As earlier explained, the floating positioning of piston 29 in cylinder 15 is the result of substantially equal forces exerted by the pressurized fluid downwards on the piston lover a cross sectional area of its wallportion 51 and upwards on the piston over an. eflective cross sectional area above the annular space 34. If those two cross sectional areas are exactly equal, theoretically the net vertical force on the piston will be zero. As a matter of practice, however, the weight of the piston produces an additional downward force thereon,*and, also, the piston is subjected to some drag by the contact of its seal ring 31 with the inner wall of the cylinder To compensate for those weight and drag forces, the cross sectional area 'of the piston'which is effectively subjected to upward force by the fluid in space 34 can be made larger than the cross sectional area of the .wall portion 51. V

The above described embodiment being exemplary only, it will be understoodthat' the omissions therefrom,

additions thereto and modifications thereof can be made without departing from the spirit of the invention, and that the invention extends to embodiments differing in form and/or detail from that specifically described. Thus,

for example, the described apparatus can be modified to compress a tetrahedral pressure-receiving assembly by (a) replacing the vertical bore 46 in the piston andthe four horizontal bores therein by three bores which are each at to the vertical bore 45 and which are equiangularly spaced around .the piston, (b) modifying the stationary anvil and the movable anvils to each have a triangular front face, and. (c) maintaining the feature described for the cubic apparatus of having the effective cross sectional area of the piston on which the fluid acts upwardly of the same or slightly greater value than the cross sectional area of each of thebroes of the piston in which'the movable anvils are received. 7 It can be shown that an apparatus of such tetrahedral configuration will operate in the manner previously described so that the should be noted in-connection pressure-receiving assembly will be equally compressed by all anvils, each of those anvils will be subjected to a driving force in line with the axis thereof (the force on the assembly from one anvil being reactive and those from the others being active), and the piston will be floating to permit the movable anvils in the lower bores to follow in an unconstrained manner the vertical shift of the assembly towards the upper stationary anvil.

Accordingly, the invention is not to be considered as limited save as is consonant with the recitals of the following claims.

I claim:

1. Apparatus comprising, means forming a hydraulic cylinder, a piston disposed in said cylinder and having formed therein a central space and a plurality of bores which extend in three dimensions from said space through said piston, and which include a first bore and second bores, said first bore extending axially into said piston from the front end thereof, a plurality of pressure-mulch plying anvils comprised of a first stationary anvil operably received in said first bore and of second movable anvils respectively received in slidable relation in said second bores, and means to produce by pressurized hydraulic fiuid a driving of said second anvils along the axes of said second bores towards said space and an accompanying movement of said piston in said cylinder and the second anvils contained thereby towards said first anvil so as to compress by all said anvils an object contained in said space.

2. Apparatus as in claim 1 in which said anvils and corresponding bores are six in number and are disposed in pairs alon three axis at right angles to each other.

3. Apparatus comprising, means forming a hydraulic cylinder, a piston disposed in said cylinder and having formed therein a central space and a plurality of bores which extend in three dimension from said space through said piston, and which include a first bore and second bores, said first bore extending axially into said piston from the front end thereof and at least one of said second bores being at an angle of more than 90 to said first bore, a plurality of pressure-multiplying anvils comprised of a first stationary anvil operably received in said first bore and second movable anvils respectively received in slidable relation in said second bores, means to inject pressurized hydraulic fluid in said second bores behind said second anvils to drive them along the axes of said second bores towards said space so as to compress an object contained therein between said second anvils and first anvil, and means to subject said piston to axial forces from said fluid which are substantially equal and opposite so as to render said piston axially floating in said cylinder.

4. Apparatus comprising, means forming a hydraulic cylinder, a piston disposed in said cylinder and having formed therein a central space and a plurality of bores which extend in three dimensions from said space through said piston, and which include a first bore and second bores, said first bore txending axially into said piston from ill the front end thereof and at least one second bore being at an angle of more than 90 to said first bore, a plurality of pressure-multiplying anvils comprised of a first stationary anvil operably received in said first bore and second movable anvils respectively received in slidable relation in said second bores, means to inject pressurized hydraulic fluid in said cylinder behind said piston to urge it forwardly, and means by which said fluid flows from behind said piston into said second bores to urge said piston rearwardly in substantially equal opposition to said forward urging and to drive said second anvils along the axes of said second bores towards said space so as to compress an object contained therein between said second anvils and said fisrt anvil.

5. Apparatus comprising, a housing containing a hydraulic cylinder having a reduced diameter well in its bottom, a piston having a main portion slidably received in said cylinder and a reduced diameter stern portion fitted in said well, said piston having formed therein a central space and a plurality of bores extending in thre dimensions from said space through said piston and comprised of a first bore and second bores, said first bore extending axially into said piston from the front thereof, at least one of said second bores being at an angle of more than 90 to said first bore, and none of said second bores having an opening into said well, a plurality of pressuremultiplying anvils comprised of a first stationary anvil operably received in said first bore and second movable anviis respectively received in slidable relation in said second bores, means to inject pressurized hydraulic fluid behind the annular region of said piston between the main portion thereof and the reduced diameter stern portion thereof so as to urge said piston forwardly, seal means obstructing the entry of said fluid into said well, and means enabling flow of said injected fluid into said second bores behind said second anvils to drive them along the ates of said second bores towards said space so as to compress an object contained therein between said second anvils and said first anvil.

6. Apparatus as in claim 5 in which said fluid in said second bores urges said piston rearwardly over substantially the same effective cross sectional. area as that over which said fluid acts in said annular region to urge said piston forwardly so as to render said piston axially floating in said cylinder. 7

7. Apparatus as in claim 5 in which closure means at the forward end of said housing permits selective opening and closing of the housing at that end, and in which said first anvil is mounted on and projects inwardly from said closure means.

References Cited by the Examiner UNITED STATES PATENTS 3,049,756 8/62 Gerard et al. 3,693,862 6/63 Gerard et al 18-165 WILLIAM J. STEPHENSON, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,169,273 February 16, 1965 Jacob Brayman It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 6, for "horizontal" read horizontally column 8, line 5, for "liens" read lines line 71, for broes" read bores column 9, line 32, for "axis" read axes line 36, for dimension" read dimensions line 57, for "tpcending" read extending column 10, line 20, for "thre" read three line 37 for "afes" read axes Signed and sealed this 10th day of August 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims

1. APPARATUS COMPRISING, MEANS FORMING A HYDRAULIC CYLINDER, A PISTON DISPOSED IN SAID CYLINDER AND HAVING FORMED THERIN A CENTRAL SPACE AND A PLURALITY OF BORES WHICH EXTEND IN THREE DIMENSIONS FROM SAID SPACE THROUGH SAID PISTON, AND WHICH INCLUDE A FIRST BORE AND SECOND BORES, SAID FIRST BORE EXTENDING AXIALLY INTO SAID PISTON FROM THE FRONT END THEREOF, A PLURALITY OF PRESSURE-MULTIPLYING ANVILS COMPRISED OF A FIRST STATIONARY ANVIL OPERABLY RECEIVED IN SAID FIRST BORE AND OF SECOND MOVAVLE ANVILS RESPECTIVELY RECEIVED IN SLIDABLE RELATION IN SAID