US2786410A

US2786410A - Hydraulic press construction

Info

Publication number: US2786410A
Application number: US71527A
Authority: US
Inventors: Harding F Bakewell
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-01-18
Filing date: 1949-01-18
Publication date: 1957-03-26
Anticipated expiration: 1974-03-26

Description

March 26, 1957 H. F. BAKEWELL 2,786,410

HYDRAULIC PRESS CNSTRUCTION Filed Jan. 18, 1949 5 Sheets-Sheet 1 March 26, 1957 H. F. BAKEWELL HYDRAULIC PRESS CONSTRUCTION 5 Sheets-Sheet 2 Filed Jan. 18, 1949 l 1N VEN TOR. QLQD/Nc; ,DAKEWELL H. F. BAKEWELL HYDRAULIC PRESS CONSTRUCTION March 26, 1957 Filed Jan. 18, 19419 5 Sheets-Sheet 3 March 26, 1957 H. F. BAKEWELL 2,786,410

HYDRAULIC PRESS CONSTRUCTION Filed Jan. 18,l 1949 5 Sheets-Sheet 4 fil?. 1l; i E 75 l g f LA] liu ieservof'r I g A y I INVENTOR.

MLM l I HqeofA/@JBA/EWELQ u l l BY L n/a 8g ORNE V5.

March 26, 1957 H. F. BAKEWELL HYDRAULIC PRESS CONSTRUCTION 5 Sheets-Sheet 5 Filed Jan. 18, 1949 INVENTOR. Meow@ llfwaz.,

J Aff .v--roe/wsys United States Patent O HYDRAULIC PRESS CONSTRUCTION Harding F. Bakewell, San Marino, Calif.

Application January 18, 1949, Serial No. 71,527

6 Claims. (Cl. 100-269) The present invention relates generally to hydraulic presses and similar machine tools, and more particularly to hydraulic presses designed for extremely heavy loadings, reaching magnitudes heretofore unknown.

So far as is known, the number of hydraulic presses designed for total loads of the order of ten thousand tons and up, is very limited. Of course the greatest obstacle to building a conventional style of press of this size lies in the need for a frame big enough to withstand the reaction to the total working loads. In relatively small presses, the frame can be of a general C-shape in which the reaction loading produces a combination of tension and bending stresses. ln larger presses, this loading has been changed by building a structural steel frame in which the loads are taken almost entirely in tension. A structural steel frame able safely to resist a loading ot ten thousand tons or more without undue deformation must be a massive affair which is not only diflicult to design but expensive to construct.

As an example of the construction problems, it is estimated that the bed alone of a sixty thousand ton press would weigh some 50() tons or more. This is too large a piece to be made as a single casting of the conventional type; and even if it could be cast, it could not be transported to the place of use as railways and highways cannot carry loads of such size and weight. These considerations point tothe need for novel features permitting assembly of the press in place from parts fabricated elsewhere.

It is therefore a particular object of my invention to provide a hydraulic press construction of unprecedented size, having a capacity in the vicinity of sixty thousand tons or more.

It is also an object of my invention to provide a novel type of hydraulic press construction which dispenses with the conventional type of frame structure necessary to resist the reaction to the working loads.

A further object of the invention is to provide a hydraulic press construction of novel design which permits the application of heretofore unprecedented working loads with a structure of comparative simplicity and low cost.

Another object of my invention is to devise a press construction utilizing as far as possible prefabricated parts that do not require special machine tools for machining the parts and can be assembled in place with a minimum of labor and effort.

t is also another object of the invention to provide a hydraulic press of the character described which is relatively simple in construction and maintenance and reliable in operation.

These and other objects and advantages are attained according to my invention by building a hydraulic press between two spaced earthen masses or walls which resist the reaction to the working loads and transmit the reaction to the earths crust. These walls may be supplied in a natural manner, as for example by utilizing ICC the Walls of a narrow canyon or a fissure in the earths crust, or a cave, in which case the ceiling and door may be used. Since the location of suitable natural formations may not always be advantageous, it is contemplated that such spaced earthen walls or masses may be prepared at convenient locations, as by driving a shaft into the ground and forming at the inner end of the shaft a chamber of a suitable size to receive the press. This arrangement has the advantage that the size and location of the chamber can be controlled as desired and that it then may be possible to utilize a denser stronger material, as for example bedrock, which has a relatively higher unit bearing power. The shaft can be vertical, horizontal, or inclined, as may be best suited to conditions.

' The two earthen masses are suitably spaced to provide a pair of spaced opposing faces. An abutment of the press is placed in load transmitting contact with each of the opposed faces, and the remainder of the hydraulic press means is between and bears against the abutments when the Working load is applied to the press. If the press is a vertical one, the entire deadweight of the press and its component parts may rest upon one abutment which in turn rests upon the floor or bottom wall of the chamber. lf the press is horizontal, much of the dead load of the component parts may be supported in dependently of either abutment, although it is preferable to maintain a certain minimum pressure against each abutment at all times.

In a preferred form of the invention, earthen masses occurring naturally in whole or in part are used to provide buttresses of suitable size and spacing that are part of and interconnected by the earths crust. The buttresses are then relatively immovable under the working loads applied horizontally to them.

How the above objects and advantages of my invention, as well as others not specifically mentioned herein, are attained will be more readily understood by reference to the following description and to the annexed drawings, in which:

Fig. l is a vertical section through a vertical shaft and chamber in the earth, showing schematically the arrangement therein of a horizontal press, the figure being vertically compressed;

Fig. 2 is an enlarged View of the press and other portions of Fig. 1;

Fig. 3 is an elevation of the press of Fig. 2 taken on line 3 3 of Fig. 2;

Fig. 4 is a plan of the press construction of Fig. 2;

Fig. 5 is a fragmentary plan and horizontal section on line 5 5 of Fig. 2 showing construction details of two typical individual cylinders;

Fig. 6 is a vertical section on line 6-6 of Fig. 5;

Fig. 7 is a diagrammatic layout of the main system for supplying hydraulic fluid under pressure to the press;

Fig. 8 is a vertical section on line 8-8 of Fig. 7 through the metering device;

Fig. 9 is a diagrammatic layout of the auxiliary system for supplying hydraulic fluid under pressure;

Fig. l0 is a vertical section through a horizontal shaft and chamber in the earth showing a variational form, of my invention; and

Fig. 1l is an elevation on line 11-11 of Fig. 10.

Fig. l represents a vertical section through a portion of the press, indicated at 14 and 15. Thus the 'two abut`

l ments

14 and 15 are themselves spaced apart and substantially vertically extending.

Abutments

14 and 15 are preferably heavy metal plates or the like, or built-up structures if desired. They do not bear directly against thenativerock or soil which provides the wall faces V12 unless -faces 12 are polished smooth; but a layer of high strength concrete 16, or other similar moldable or plastic material, is introduced between the wall faces and the abutments in order to form a matrix that levels off the inequalities of the walls i2 and receives the abutments to evenly distribute the load from the abutment over the associated earthen face 12. Concrete layer 15 also assist-s in keeping the abutments in position by fastening them to the earthen walls.

The earth masses may be naturally occurring or articially formed in whole or in part. I prefer to drive a shaft into the earth and at the end enlarge it as necessary to form a `press chamber. This permits the press construction t-o be enclosed and protected and, if desired,

concealed. Also it is possible to reach a strong dense rock formation to provide the walls 12; but it -is to be understood that my invention is not necessarily so limited since masses of sand or soil may be sufficiently compacted las to yprovide the desired bearing power. For this reason, shaft 10 may be of any desired length or shape.

The stationary bed of the press comprises labutment 14, stationary die or bed plate 18 and an -intermediate load distributing member 20 disposed between the stationary bed plate and the abutment. 29 isdesigned so that the transverse cross sections change progressively 'in the direction of thrust. It is here shown a being in the shape of a truncated rectangular pyramid with the smaller base engaging the back side of plate 18 and the larger base engaging the front side of abutment 14, but other suitable shapes may be used, if desired, which are adapted to distribute the load of the bed plate over a larger area on the abutment. As shown particularly in Fig. 2, the total area of abutment 14 may be still larger than the area of the larger base of load disitributing means -20 in contact with the abutment.

The load distributor 20 lis composed -of ya plurality of metal 'bars of rectangular cross sect-ion larranged in a plurality of layers parallel to plate 18 with the .bars of successive layers extending at substantially right angles to each o-ther. The layers are shown as having progressively changing numbers of bars `of the same size. The number may change at a selected regular interval, as every other layer or every fourth layer according to the rate of increase of the area over which the load is disf" tributed.v In lth'is construction, as will be apparent from Fig. 2, the layer with the smallest number of bars is adjacent the bed plate while the layer with the largest number yof bars is adjacent abutment 143. However, other arrangements of bars may be used, since wider bars may be used at equal spacings instead of a larger number of Ibars or the spacing between bar-s may be changed from one layer to another.

In constructing the press, it is contemplated that the bars will be all finished to provide two flat, parallel faces on each so that maximum bearing and accurate alignment are secured. When in place the bars are welded to each other to build up the crib-like Iarrangement for distributing the loa-d. The bars are of a conventional size and are made of cold rolled steel or other stock having a high compression strength.

Cooperating with the stationary bed of the press, is the traveling head which is of similar construction to the bed except lthat the parts are arranged in reverse order. The traveling head comprises'movable platen or die plate 21, load distributing means 22 and pressure plate V24. Load distributing means 22 is constructed in the same manner as the load distributing means 20 just described. It serves to distribute the Working'load on platen 21 over a larger area on'pressure plate 24, which area is prefer- Load distributing means ably something less than the total area of pressure plate 24. As will be apparent from later description, the load distributing means 22 may also be Viewed as a force concentrator, the object of which is to concentrate the unit pressure applied to the pressure plate to a higher unit pressure applied Ito platen 21.

interposed between abutment 15 `and pressure plate 24 is hydraulic means for moving the platen `and traveling head with respect to bed plate 13 and the stationary press bed. This hydraulic means comprises a plurality of individuai and separate cylinders 26 with their longitudinal axes parallel to each other and perpendicular tothe face of abutment l5. Typical cylinders are shown in detail in Fig. 5 and each preferably comprises a base 2S to which is attached a cylindrical tube that forms the cylinder walls and within which piston 29 is axially movable. In order to mount the cylinders in place, abutment 15 is preferably provided with `a plurality of vertically extending grooves 30 with outwardly converging side walls so that the cylinder bases 28 can be fastened to the abutment by a dovetail connection. This arrangement permits the bases 2 of a number of cylinders to Ibe inserted in the upper end of a groove 3i) and lowered within the groove to form a vertically extending row of cylinders. The bases are square, as shown in Fig. 6, and rest one upon another. The outer ends of the cylinders are positioned by spacers 32 4to keep the axes of the cylinders properly aligned and parallel. The fluid under pressure is admitted to the cylinder interior through a passage 33 formed within the cylinder base 23; and pressure is retained within the cylinder by O-

rings

34 and 35 in the base and piston respectively, or other suitable packing.

Although other types of hydraulic cylinders may be used, the particular construction utilizing a large number of individual, open-ended cylinders with a piston projecting outwardly from the open end of each cylinder has been `adopted because of its simplicity. The cylinders and pistons can be easily made from materials of standard sizes and assembled `on the job. Not only is original manufacture simplified but replacement and repair are likewise rendered easy.

A large number of relatively small hydraulic cylinders is preferred because unit stresses and pressures are lower and the parts are much easier to manufacture. The cylinders are arranged as closely together as possible on abutment 15 so that the maximum number of pistons can be brought to bear against the back side of pressure plate 24, for 4a given area on the plate. As shown in Figs. 5 and 2, the ends of the pistons may be slightly rounded in order to keep the area of contact of each piston centrally located on it and so eliminate eccentric loadings on the piston.

When walls 12 and

abutments

14 and 15 extend vertically as in Fig. 2, the press is of the horizontal type in that the movement of the platen and the direction of application of working force are both horizontal. To support the platen during this horizontal movement, there is provided a pair of

ways

33 and 39, as shown in Fig. 3. One of the ways as shown at 38, has a V-shaped upper surface which is designed to give lateral guiding action to the platen as it moves back and forth along the way, since deviation from a straight line movement is resisted by the inclined sides of the top surface of way 33. One or more additional ways 39 are provided having at top surfaces. A way of this character merely supports the vertically imposed weight of the traveling press head.

Ways

38 and 39 are supported upon foundations 4t) which support the ways and the dead weight of the traveling head independently of the abutments. As shown in Fig. 2, foundations d@ may have enlarged'footingsat the ends to support better the weight of the abutments. Foundations 40 are preferably set in a matrix di of concrete or similar material to enable it to evenly and more widely distribute its load over the earthen formation on which it rests.

Although the principal hydraulic means provided by cylinders 26 moves the platen during pressing operations, it is desirable to provide auxiliary hydraulic means adapted to move the platen back and forth, as when the dies are being brought into initial engagement with the work or when the platen is being moved away from Ithe work to permit withdrawal of the work from the dies. This auxiliary hydraulic means comprises a pair of opposing

hydraulic cylinders

42 and 43 pivotally connected to

abutments

14 and 15 respectively at each of the four corners of the abutments. Each cylinder has a piston 44 yor 45 respectively which is pivotally connected to one corner of pressure plate 24. By filling cylinders 43 with pressure fluid, pistons 45 are forced outwardly and pressure plate and platen 21 are advanced toward the Work and stationary bed 18. Reverse movement of lthe pressure plate and platen occurs when cylinders 42 are filled with fluid under pressure to force pistons 44 outwardly.

Abutments

14 and 15 are held in spaced relation at all times by means of adjustable braces 50 located at the corners of the abutments. In a simplified form, the braces 50 consist of compression posts provided with nuts 51 which may be screwed down against sleeves 52 in order to place posts 50 under compression. The outward pressure thus exerted holds the abutments rmly against the bearing walls 12 and helps maintain proper relative positions of the abutments.

Since it is desirable that posts 50 be automatically extended to compensate for settlement of either abutment, the end of each post is spaced from the base of the socket and sleeve 52, and hydraulic uid under pressure is preferably introduced therein by pipe 53. Braces 50 thus automatically extend to maintain a constant minimum pressure between the abutments inthe event of any settlement causing the abutments to move apart.

A preferred form of fluid supply system is show-n schematically in Fig. 7, and also in part in Fig. 4. The fluid supply system comprises one or more low volume, high pressure pumps 55 and a high volume, low pressure pump 56 each driven by a suitable prime mover, as for example

electric motors

57 and 58 respectively. Fluid is supplied to the pumps from reservoir 60 vthrough suitable piping. The output from the high pressure pumps passes through check valves 61 which maintain unidirectional flow in the lines. A common delivery line 63 leads from pumps 55 to accumulators 64 and to metering device 66. The ou'tput from the low pressure pump 56 also enters delivery line 63 at a point beyond check valve 62. The fluid delivery line 63 is divided into a plurality of branches 67, here shown as four in number, each leading into a separate chamber 68 in meter 66. Each chamber 68 is circular in outline and contains an eccentrically mounted rotor 69 driven by shaft 70 and provided with a plurality of radially sliding vanes 71. This construction is similar to a conventional sliding vane rotary pump. The quantity of fluid passed by each chamber is proportional to its volume; and for a given diameter, lthe volume varies directly with the axial length of the chamber. Shaft 7th extends entirely through meter 66 and has attached to it the four rotors 69 disposed one in each chamber 68. Shaft 70 is driven through gears'72 and shaft 73 from any suitable prime mover, not shown in the drawings.

By turning rotors 69 in unison, meter 66 receives fluid under pressure from lines 67 and discharges, a quantity of fluid under pressure into each of lines 74 that is proportional to the volume of the corresponding chamber 68 in meter 66. The four pipe lines 74 conduct the fluid under pressure to manifold 75 which is provided with four separate and individual chambers to each of which one pipe line 74 is connected. Pressure fluid leaves each chamber of manifold 75 through a plurality of pipes 77, therebeing one such pipe for each cylinder 26. Some of the pipes, especially pipes 77, have been omitted from the figures in the interest of simplicity and clarity. Each pipe' 77 is connected to the fluid passage 33 in base 28 of the cylinder, as shown in Fig. 5.

By this arrangement, the delivery of fluid from the fluid supply system is controlled to equalize the quantity of fluid received by each chamber of manifold and the group of hydraulic cylinders receiving fluid therefrom. In the arrangement just` disclosed, the cylinders are divided along horizontal lines into four groups, one above another, each group being supplied from a separate manifold chamber and the total amount of fluid received by that group being determined by one of the units of meter 66. As shown in Fig. 3, the number of lines 77 leading from each manifold chamberr to the top and bottom groups of cylinders is smaller than the number to the two middle groups. The two inner chambers 68 of meter 66 are larger than the end chambers in proportion to the number of cylinders supplied from those chambers and the corresponding middle chambers of manifold 75. Consequently every cylinder receives substantially the same volume of fluid per unit time. The purpose of this arrangement is to insure equal advance of the platen at the top and bottom and to prevent its misalignment with respect to the stationary bed plate 18, as might otherwise occur when the die contacts the Work initially at a single poin't with the result that not all cylinders 26 encounter an equal resistance. Uneven resistance would create unequal fluid distribution unless some fluid metering device is used. It will be obvious without further detailed description how the number of groups of cylinders may be increased by, sub-.dividing the present groups along either horizontal or vertical lines. In this event, the number of conducting lines 74, chambers in manifold 75, and units in meter 6 6 are all increased accordingly.

Fluid under pressure may be delivered to

cylinders

42 and 43 either from pump S6 or by a separate fluid supply means, if desired. The latter arrangement is preferred and isr here illustrated in Fig. 9 as comprising four sep arate positive displacement pumps S0 which are supplied with fluid by lines 79 from reservoir 60 and all driven in unison by one electric motor 81, or other prime mover, by a single shaft 81a. The delivery line 82 from each pump has two

branches

82a and 82b each adapted to deliver fluid under pressure to one of

cylinders

42 or 43, respectively. Delivery to a selected

branch

82a or 82!) is controlled by suitable valves, as at 83, and may be at a comparatively high or low pressure as desired. There being fourpairs of

cylinders

42 and 43, it is essential that the advance of all four

pistons

44 or 45 be equal. For that reason it is preferred to use four positive displacement pumps of equal size delivering fluid at the same rate; although other metering means, such as the type previously described, may be used.

Cylinders

42 and 43 being opposed to each other, one is exhausted necessarily when the other is filled. For this purpose valves -83 are made four-way valves and the line 84 at each valve is a fluid return line connected to the main return line 89 leading to reservoir 60. When the valves are in the position of Fig. 9, the fluid under pressureI` goes to cylinders 43 while the exhaust fluid from cylinders 42 goes back through

lines

82a and 84 to 89 and reservoir 60. When valves 83 are rotated 90, cylinders 42 are filled and cylinders 43 are exhausted. Valves 83. are preferably interconnected to all move together. Of course the invention is not limited to this particular piping arrangement, it being possible to use others that may occur to persons skilled in the art.

All the component parts of the fluid supply means `shown diagrammatically in Figs. 7 and 9 may be located at any suitable place, as for example in the bay or recess 85 in one of the side walls of the press chamber.

The operation of the press is controlled from any suitable location, preferably some location from which the operator can watch the work in the press, as control ele' vator 86 in a bay 87 in one of the side walls of the chamber. Elevator 86 carries with it control console 88 on which all the. necessary controlsV are. grouped. These.

to reservoir 60Vthrough, lines 89; and controls for craneV 90 at the head of shaft 10 by. means of. which the work can be lowered tothe press and raised to the ground surface.

I sha1-l now describe briefly the operation of the press. Initially, the platen` 21 is moved away from stationary bed plate 18 by moving the platen toward the left as viewed in Fig. 2. This is accomplished by introducing pressure iluid. into cylinders 42, thus vforcing pistons 44 out ofthe cylinders and moving pressure plate 24-to the left. This movement causes pistons 29 and 145 to move into

hydraulic cylinders

26 and 43 respectively, exhausting fluid from all these cylinders into reservoir 60. Return flow from cylinders 26 is in a reverse direction through lines 77, manifolds 75 and a portionof lines 74.

A check valve 74a in each line 74 automatically closes toy prevent the reverse flow from entering the meters 66, and valves 89a are opened by the operator to divert ow from lines 74 into return lines 89 whichV empty into reservoir 6l?. Return ow from cylinders 43 (and also cylinders 42 when they are exhausted) isthrough lines 84 which` are connected directly to return lines 89 as mentioned above. This initialmovement of the platen can be accomplished at a relatively low,pressure and high speed. Next, suitable dies (notr shown) areattached to the die plates 13 and 21 and the material to be worked is lowered by'V crane 90 into position between the dies. This operation is controlled by an. operator on control platform S6, and heraises or lowers the platform to bring himself into position from which he can best view the work of the press. i

Initial movement of the platen to the work can be accomplished at relatively high speed and low pressure by introducing fluid at a lowpressure into cylinders 26, thus forcing outwardly pistons 29 which move pressure plate 24 toward the right as viewed in Fig. 2. This movement can be continued until light initial engagement of the dies with the work piece is obtained. Alternatively, movement of the traveling head toward the stationary bed can be accomplished by using pumps 80 to introduce fluid into cylinders 43, thus moving pistons 45 to the right asviewed in Fig. 2. The final power stroke requires the application of relatively tremendous pressures and so must be accomplished by introducing uid at high pressure into each of cylinders 26. Because of the relatively large total volume of all the cylinders 26, forward movement of pressure plate24 and platen 21 is comparatively slow when using the highpressure system. Because of the large number of hydraulic cylinders in the group applying pressure. to plate 24, an unprecedented total workingv force is made available, even though the highest pressure in the high pressure hydraulic system is not unusually high. By keeping the size. of kcylinders 26 relatively small, the hydraulic lines supplying liquid thereto may likewise be small and all these parts can be economically designed to resist the kmaximum loading imposed upon them.

In the drawings ,I have shown eleven horizontally spaced, vertically extending rows of cylinders 26 with twenty-two .cylinders in eachrow. This is a `total of 242 cylinders in the primary hydraulic system. If the net area to which hydraulic pressure is applied on each piston 29 is' 100 square inches and the maximum working pressure within each cylinder is"5,000 poundspersquare inch,

8 thenthe total force exerted by each piston 29-is 500,000 pounds. The gross working force that can be applied to pressure plate 24 by all pistons 29 is then 121,000,000 pounds,`or slightly over 610,000 tons.

There is illustrated in Figs. 10 and 11 a variational form of my invention in which the shaft 10a inthe ground' is a horizontal shaft with the press chamber atV the inner end of the shaft. This is a typical installation when the pressl is located in a mountain. Under these circumstances, it may be preferablerto utilize the floor and ceiling of the press chambers as the opposed spaced walls 12 between which the press is located in load transmitting engagement with both walls. The press is then the vertical type, that is, the traveling head moves in a vertical path relative to a stationary bed comprising bed plate 18, load distributing member 20, and abutment 14 Which are stationary and supported on the floor of the chamber.

In general, the construction of the vertical type press is the same as the horizontal type press previously described, with the exception that gravity may be utilized to lower the traveling head toward the press bed so that hydraulic means for this purpose can be dispensed with, and the entire dead load of the component parts of the press is carried on one abutment and one of the opposed vment 15 and so maintain

abutments

14 and 15 properly spaced and aligned in thevsame manner as braces 50; and 1n addition these four posts guide the traveling head in its movement toward and away from the press bed. This is accomplished by providing pressure plate 24 with extensions through which posts 91l pass; and, in order to attain greater rigidity, a frame 92 mounted on the upper load distributing member 22 also slides on guides 91. Thus the traveling head is slidably mounted on these corner guides to direct its movement.

A plurality of hydraulic cylinders 94 and pistons 95 therein are provided, there being shown in the drawings four such piston and cylinder arrangements located two at each end of the press. These cylinders constitute the auxiliary hydraulic means adapted, to move the platen upwardly away from the bed plate 18, it being understood that no hydraulic means for reverse movement is required because downward movement is under the force of gravity.

One or more bays 97 are formed in the chamber side walls to accommodate the fluid supply systems, the operating console and any other auxiliary equipment that may be desired. With the vertical press, it may-be preferable to omit the control elevator 36 and to mount the control console 88 ina fixed location.

Although the changes in construction described in connection with the form of press shown inFigs. 10 and 11 may bring about minor vchanges in operation, it will be understood that the general principles of operation of the two forms of press are the same. For example, gravity may be used to lower theplaten and die to engagement with the work, instead of using hydraulic means. During the following work stroke, theV weight of the platen, pressure plate, and the upper load distributing means 22 are added to the pressure of the pistons to determine the total working force applied.

Having described certain embodiments of my invention,

it will be understood that various changes in theform, construction, and arrangement of parts will occur to and may be made by persons skilled inthe art without departing from the spirit and scope of my invention; and consequently I wish it understood that the foregoing description is considered to be illustrative of, rather than limitative upon, the appended claims.

I claim:

1. In a very heavy-dutythydraulic `press construction,

the combination comprising: a pair of spaced earthen masses; a pair of fixed spaced abutments, an abutment being in work-load transmitting relation to each of said earthen masses and one abutment having a plurality of spaced parallel grooves; a stationary bed plate'supported by the other of said abutments in load transmitting relation thereto; a movable platen cooperating with the bed plate; and hydraulic means for moving the platen toward the bed plate to apply working forces, said hydraulic means comprising a relatively great plurality of separate, open ended hydraulic cylinders individually and slidably supported on said one abutment in load transmitting relation thereto and a piston in each cylinder projecting beyond the cylinder into engagement with the platen, the hydraulic cylinders being arranged in a plurality of closely adjacent rows each of which rows includes a plurality of closely adjacent cylinders slidably mounted in a single groove by a dovetail connection at the base of the cylinder.

2. A hydraulic press as in claim 1 in which the platen moves horizontally and the grooves in the abutment extend vertically, the cylinders in one vertical row resting on each other at their bases.

3. In a very heavy-duty press construction, the combination comprising: a pair of spaced earthen masses providing a pair of spaced opposed faces, each mass being a part of the earths crust and connected thereby to the other mass; an abutment in work-load transmitting relation to each of said faces of the earthen masses; a stationary bed adjacent and in load transmitting relation to one of said abutments; a platen movable toward and away from the bed to shape a work piece between the bed and platen; and adjustable bracing means holding the abutments apart, said bracing means comprising a plurality of compression members interposed between the abutments and each compression member including hydraulic means maintaining substantially uniform compression in the compression member at all times.

4. A press adapted to be supported within an opening in the earth having opposed walls, comprising: a pair of spaced xed abutments, each abutment being so positioned relative to one of said opposed walls of the opening as to be in abutting contact with said one Wall throughout substantially the entire exterior surface area of the abutment; a movable pressure plate between said abutments; work abutting means positioned between the pressure plate and one of said abutments comprising a movable platen and a fixed bed plate mounted in facing relationship respectively on the movable pressure plate and on said one abutment; load distributing means mounted on facing surfaces of the pressure plate and said one abutment to support thereon the work abutting means; pressure applying means bearing against the interior surface of the other labutment and against the pressure plate to move the movable platen toward the stationary bed plate; and adjustable means normally adapted to maintain the abutments in abutting relation with the opposed walls of the opening within which the press is positioned,

5. A press comprising: -a base adapted to be supported on the bottom of an opening in the earth having opposed walls and within which opening the entire press is adapted to be housed; a pair of spaced fixed abutments supported upon said base, each abutment being so positioned relative to one of said opposed walls of the opening as to be in abutting contact with said one wall throughout substantially the entire exterior surface area of the abutment; a

kmovable pressure plate between said abutments; work abutting means positioned between the pressure plate and one of said abutments comprising a movable platen and a fixed bed plate mounted in facing relationship respectively on the movable pressure plate and on said one abutment; load distributing means mounted on facing surfaces of the pressure plate and said one abutment to support thereon the work abutting means; pressure applying means bearing against the interior surface of the other abutment and against the pressure plate to move the movable platen toward the stationary bed plate; and adjustable means normally adapted to maintain the abutments in abutting relation with the opposed Walls of the opening within which the press is positioned.

6. 1n a heavy duty press adapted to be supported and housed within an opening in the earth having a plurality of earthen walls including a bottom wall, two of said walls being opposed to each other, the combination comprising: a pair of spaced abutments each formed and disposed to bear outwardly against one of said opposed walls of the chamber over substantially the entire exterior surface of the abutment; a stationary bed plate on one of the abutments at an inwardly facing surface of said one abutment; a movable platen disposed between the bed plate and the other abutment; pressure applying means disposed between said other abutment and the movable platen for applying working forces by moving the platen toward the bed plate, said pressure applying means being mounted on the inwardly facing surface of said other abutment to bear thereagainst; a pressure plate movable with the movable platen and disposed to receive the thrust of the pressure applying means; rand means for guiding and supporting the pressure plate, including foundation means bearing against the bottom wall of the chamber.

References Cited in the le of this patent UNITED STATES PATENTS 168,085 Dunn et al Sept. 28, 1875 178,965 Sellers June 20, 1876 812,228 Von Philp Feb. 13, 1906 886,956 De France et al May 5, 1908 1,309,384 Yeomans July 8, 1919 1,662,727 Wait Mar. 13, 1928 1,693,343 Morgan Nov. 27, 1928 1,907,083 Meyercord et al May 2, 1933 2,056,331 Shutt Oct. 6, 1936 2,092,092 Sinclair et al Sept. 7, 1937 2,098,425 Landenberger Nov. 9, 1937 2,216,484 Bausman Oct. 1, 1940 2,306,716 Albers Dec. 29, 1942. 2,327,869 Carlson Aug. 24, 1943 2,387,190 Stone et al. Oct. 16, 1945 2,387,839 Frost Oct. 30, 1945 2,450,972 LeTourneau Oct. 12, 1948 2,492,878 Miollis Dec. 27, 1949 2,523,871 Mavor Sept. 26, 1950 2,550,674 Curtis May 1, 1951 2,573,993 Sedgwick Nov. 6, 1951 FOREIGN PATENTS 76,469 Switzerland May 16, 1918 411,413 Great Britain lune 7, 1934 OTHER REFERENCES Engineering News Record, of Mar. 18. 1948, vol.

140, pages 98 and 99 (vol. pages 426 land 427).