US2882815A - Press - Google Patents

Description

April 21, 1959 e. P. M. BERNIER PRESS 3 Sheets-Sheet 1 Filed March 12, 1956 .l I I MN g mm .|l|l|l||v ll] a 1 4 n N 1 3 KM Q. m :1 Nm %N 3 mm mm April 21, 1959 G. P. M. BERNIER PRESS 3 Sheets-Sheet 2 Filed March 12, 1956 Ill l Q Q April 21,1959 G. P. M. BERNIER PRESS 3 Sheets-Sheet 3 Filed March 12, 1956 PRESS Gaston Pierre Marie Bernier, Chalonnes-sur-Loire, France, assignor to Constructions Meca-Metalliques Chalonnaises, Chalonnes-sur-Loire (Maine-et-Loire), France, a corporation of France Application March 1-2, 1956, Serial No. 571,055 Claims priority, application France March 16, 1955 5 Claims. (Cl. 100 .-.-52)

The present invention relates to presses intended for expressing juices and other liquids from various products, such as grapesyapples, pears, and the like, which is of the type comprising. a screen formed by a sort of barrel which is mounted to rotate about a horizontal axis and inside which is placed the fruit or other product to be pressed, while the juice or other liquids flow through the free longitudinal gaps left between the bars of the screen.

For pressing the product contained in the screen, various solutions have already been proposed. One solution is to provide two. keyed plates which are coaxial with the screen and are slidable in relation to the latter, these plates forming nuts engaged on two oppositely directed screw threads formed on a fixed screw, so that by rotation of the screen in one direction the plates are brought nearer to one another, while they move apart on rotation of the screen in the other direction.

The product to be pressed is accommodated between the two plates and is therefore compressed axially in proportion as the plates move towards one another. Experience shows that this arrangement does not enable uniform pressure to be applied in the interior of the compressed product, and this pressure, which is particularly great near the plates, decreases progressively from the plates towards the median plane of the space therebetween and from the periphery of the screen towards the centre. The result is usually that the juices or other liquids are completely extracted only after a very long period of operation.

Another solution is to provide a screen having two fixed ends and disposing in said screen, coaxially thereto, an expansible hollow body which is inflated by the introduet'on of air under pressure.

.In this case the product to be expressed is compressed in the centrifugal radial direction between the expansible body and the screen, in the form of an annular mass which, in the case (If most products, very quickly be comes, compact, while itsperrneability declines to such an extent that the liquid soon becomes very diflicult to express. 7

The. object of the present invention is to provide apress of the type comprising a rotating screen and two plates moving in opposite directions on a fixed axial crew n which said pla w h are a ly y d relative to the screen, form nuts, said press being characterised in that there is disposed between said plates and around the screw a hydraulic core of constant volume but deformable, and which isconstituted by a fluid-tight chamber ofannularcross-section surrounding the screw' and filled with a liquid, that is a fluid but incompressible product.

in one embodiment, the fiuidvtight wall of this chamher is formed .by the combination of atubular sleeve, of rubber or like-elastic, deformablematerial, and two end. pieces on which said sleeve is fixed to be fluid-tight, said end pieces forming fluid-tight nuts .on the screw and i df jjf' j; at

2,882,815 Patented Apr. 21, 1959 being rigid with the two movable plates in respect of rotational and longitudinal displacements of the latter.

As a result of this arrangement, when the two plates move towards one another, the shape of the chamber, and consequently the hydraulic core, changes without its volume altering. This chamber, which has a cylindrical shape when the plates are moved apart to the maximum extent, assumes the shape of a truncated double cone, while its elastic wall contracts to adapt its length to the new shape. As a result of the broadened shape of the chamber when the two plates move towards one another, it will be found that the pressure inside the product expressed is distributed much better and that the flow of the liquid towards the screen is no longer obstructed.

When the plates are moved apart between the successive stages of expressing the product, the hydraulic core always resumes its initial elongated shape, without any variation in volume, thus promoting the breaking up of the cake formed for the following expressing stage.

According to another feature of the invention, the fluid-tight chamber is connected to a closed chamber by a movable member connected to a push member which controls a switch controlling the circuit of the driving motor of the rotating screen, for the purpose of opening the supply circuit of said motor when the pressure of the liquid contained in the constant volume chamber attains a given value and closing it when the pressure falls to a predetermined lower value.

When the product to be expressed is readily pressed, the fluid-tight constant volume chamber may be provided only for the purpose of controlling the switch and in this case said chamber may be of very small volume.

Other features will be clear from the description hereinbelow.

In the accompanying drawing, which is given solely by way of example:

Fig. l is an elevational view, on a small scale, of a press embodying the invention;

Fig. 2 is an end view thereof;

Fig. 3 is a longitudinal sectional view thereof, on an enlarged scale;

Fig. 4 is a detail view showing the method of anchoring the screw in the supporting frame;

Fig. 5 is a view similar to Fig. 3 of the position assumed by the moving parts at the end of an expressing operation;

Fig. 6 is a sectionalview, on an enlarged scale, of the connection to the hub of one of the two moving plates of the adjacent end piece of the chamber forming the hydraulic core of constant volume;

Fig. 7 is a partial longitudinal sectional view of a first modification in which the press is stopped automatically when a certain pressure has been obtained in said press, and

Fig. 8 is a similar view of a second modification.

The embodiment of the invention shown in Figs. 1 to 6 relates to a press of known type comprising a structure formed by a frame having two longitudinal members 1 and two cross-members 2 and carried by legs 3.

Fixed to the two cross-members 2 by two flat faces 4 is an axial screw 5 whose end portions, provided with these flat faces, are anchored in a bearing having two parts 6 and 7 which are fastened on the corresponding cross-member 2 (see Figs. 2, 3 and 4.). The screw 5, whose axis coincides with the horizontal axis XX of the press, has .two screw-threaded portions 5 and 5 the screw-threads of which are oppositely directed. These portionsterminate at a certain distance from the anchoringjfiat faces 4 so as ,to create two cylindrical journals 8 on each of which is rotatable a hub 9 connected by radial arms 10 to a ring 11. The two rings 11 are provided with an outer toothing 12 and form with the slats 13 a barrel-shaped-screen, which rotates about the axis XX. The slats 13 are spaced slightly apart to enable juices or other liquids resulting from expressing to flow freely therebetween.

The slats 13 are held by hoops 14. Furthermore,

the two rings 11 are tied by rods 15 which are housed inside the screen, the latter being inserted in the rings each of which are provided for this purpose with a recess 15. The screen is provided with a filling hole having a door 16 (see Fig. l).

The rotating assembly constituted by the two rings and the screen is rotated about the axis XX alternately in one direction and then the other, by a reversible electric motor 17 (Fig. 2) the supply circuit of which is controlled by a reversing switch. The shaft18 of said motor drives a pulley 20 keyed to a longitudinal shaft 21, through the medium of a belt 19 (Fig. 2). Two pinions 22 (Figs. 1 and 2) are keyed to said shaft 21 and mesh with the toothing 12 of the rings 11 of the screen.

Slidably keyed in the screen by the ties 15, are two transverse plates 23 each of which is movable longitudinally and connected by Welding or some other manner to a sleeve 24 which is rigid with a hub 25, the latter being screw-threaded at 26 (Figs. 3 and 6), so as to form a nut engaged on the corresponding screwed portion 5 or 5 of the fixed axial screw 5.

It will be seen that depending upon the direction of rotation of the screen the plates and the nuts turn in one direction or the other on the screw, thus obtaining a translatory movement of said plates either towards one another from the position shown in Fig. 3 to that shown in Fig. 5, or a movement in the opposite direction.

The assembly of known type described hereinabove is completed in the following way according to the invention. Mounted on the two portions 5 and 5 of the screw in the manner of two auxiliary nuts, are two end pieces 27 of rubber or similar material, which clamp elastically over the threaded portions of the screw with which they form a joint while serving as supports for a sleeve 28. Said sleeve 28 of rubber or like deformable and elastic material is cylindrical, of circular section, when it is elongated under longitudinal tension (the position shown in Fig. 2). Its two ends are fixed in a fluid-tight manner on the end pieces 27. Each of said end pieces preferably comprises on the sleeve side thereof, as shown in Fig. 6, a shoulder of greater diameter than the rest of the end piece, the sleeve being fastened beyond said shoulder on the smaller cylindrical part of the end piece by means of a clamping ring 28.

The smaller cylindrical part of each end piece is fitted and fastened, for example by vulcanization, inside a metal sleeve 29 which extends beyond the end piece. In the part thereof not covering the end piece said sleeve is provided with holes 30. The free end of the sleeve is connected, for example by welding, at 31 (Fig. 6), to the sleeve 24 of the hub of the corresponding plate 23, so that said sleeve and the end piece 27 participate in the longitudinal movements of the hub of the plate and, in consequence, of said plate along the screw 5.

When the press is in the position shown in Fig. 3, with the two plates moved apart to the maximum ex tent, the sleeve 28, which is under elastic tension, determines between the two end pieces 27 and around the screw 5 an annular chamber of circular section having a certain volume (V). This chamber is filled with a liquid 32 which can be, for example, water or jack oil or any other liquid of the same nature as that which the press is intended to extract from the products to be expressed.

The machine operates in the following manner:

When the'machine is in the position shown in Fig. 3

and the door 16 (Fig. l) is removed (or opened), the annular space between the two plates 23, which are separated, and the sleeve 28 is filled with the fruit (grapes, apples, pears, etc.) which is to be expressed. The door 16 is then replaced (or closed) and the motor 17 started so that the rotor assembly, constituted by the screen, the plates 23 with their hubs 24, the end pieces 27 and the sleeve 28, turns in relation to the screw in the direction of the arrow f (Fig. 3).

In consequence of this rotation and of the directions of inclination of the screw-threaded portions 5 and 5 of the fixed screw 5, the hubs 24, operating as nuts, travel along said portions towards one another, and the same applies of course to the plates 23 which compress the fruit between them while the end pieces 27, connected to the nuts 25 by the sleeves 29, participate in the rotation of said nuts and move towards one another at the same speed as the nuts.

There is thus a decrease in the length of the chamber created by the sleeve 28, and as the volume (V) of the chamber is at the outset filled with liquid 32, the moving together of the end pieces 27 is manifested in a deformation of the sleeve 28, which gradually assumes the shape of a double truncated cone shown at 28 in Fig. 5, this shape being such that the developed length of the sleeve decreases, said sleeve contracting longitudinally while increasing in cross-sectional size, the volume there of retaining the initial value (V). The sleeve therefore remains full of liquid.

Owing to the shape of a truncated double cone assumed at 28 by the hydraulic core constituted by the sleeve and its liquid contents, it will be immediately seen that the fruit disposed around this core in the free space in the screen between the two plates 23, has a thickness in the axial direction of the screen which increases from the axis towards the periphery of the screen.

As pressing progresses, the particles of the expressed material are progressively deflected outwardly, while the liquid flows in the direction indicated by the arrows. In fact, the two parts of the cake formed on either side of the core between the two plates 23 are each compressed between the transverse face of the corresponding plate 23 and the slanting face of the truncated cone of the central hydraulic core, that is under conditions which are a compromise between the axial pressing obtained in the known type of machines in which the plates are moved towards one another and the radial centrifugal pressing obtained in machines having fixed plates and an expansible chamber.

In comparison with this expansible chamber, it will be seen that the hydraulic core has a constant volume and is not expansible, the sleeve 28 on the contrary contracting in the longitudinal direction, passing from the position shown in Fig. 3 before expressing to that shown in Fig. 5 at the end of compression.

Briefly, on account of the position assumed by the hydraulic core in Fig. 5, the liquid may be completely expressed in a much more rapid manner and with less trituration of the expressed product which, by this very fact, breaks up less than in either of the two known types of machines. In fact, in comparison with the first type, the pressure is much better distributed inside the two parts of the cake contained between the hydraulic core and the plates, while there is complete freedom for the liquid to travel towards the periphery, where the compression is substantially lower, since the pressure decreases from the axis towards the periphery of the screen, thus facilitating the evacuation of the liquid. Moreover, in comparison with the machines having an expansible chamber, the formation of a shell of a more or less impermeable compressed product against the slats of the screen is prevented, and the crumbling of the cake is time and facilitating draining.

When the moving assembly has reached to the position shown in Fig. 5, which is substantially anextreme position, the direction of rotation of the motor is reversed, t P at s m re apart ant ere a ti of th i nu 24, and the latter, by their connections 29 to the end pieces 27, pull on said end pieces which follow the movement, returning to theposition shown in Fig. 3. This operation, which corresponds to a decompression'of the hollow cake formed, enables said cake to be broken up, the cake being no longer supported by the sleeve, which passes from the position 28 to the rectilinear position 28 shown in Fig. 3.

As soon as the position shown in Fig. 3 is resumed, the movement in the opposite direction is recommenced, and so on for a number of times until all the liquid contained in the product is expressed.

This liquid naturally flows through the slats of the screen, thereafter trickling onto an inclined floor supporting the frame 3 which is the usual arrangement. Alternatively, the liquid is received in a container disposed beneath the press and serving as a support therefor.

It will be seen that during the expressing operation, part of the liquid may come into immediate contact, through the orifices in the sleeves 29, with the screw in the region of its threaded portions 5 and 5 This liquid thus reaches, through the roots of the screw-threads, the inside of the bore of the nuts 25, and flows through said bores which are thus sufiiciently lubricated by this liquid without need for any other lubricant.

Fig. 7 shows a first modification in which the presence of the liquid 32 inside the sleeve 28 is used to advantage to control the supply of power to the driving motor 17 of the press rotor.

To this end, there is disposed in the supply circuit 32 for the motor between the latter and a reversing switch 33 of any type, a switch 34 which is opened by a push member 35 combined in the known manner with regulating means (not shown) which, for a given force on the push member, permit regulation of the instant of disconnection and automatic reconnection when the evacuation of the juices contained in the cake has sufliciently reduced the pressure exerted on said push member.

According to the invention, said push member 35 bears, by its head, against a diaphragm 36 which constitutes a deformable wall of a chamber 37, formed by a block 38 connected to the case 39 of the switch 34. Said chamber 3''? is connected by a connection 40 to an axial passage provided in the screw 5 and communicating through a median radial hole 42 with the chamber formed by the sleeve 28.

As will be seen, when the two plates 23 of the press are brought together, the pressure exerted by the com pressed product on said sleeve 28 and the liquid 32 contained therein increases the pressure of said liquid and 1 this pressure is transmitted, without substantial volume variation, to the chamber 37 where it acts upon the push member 35 through the medium of the diaphragm 36. A pressure gauge 43 can be connected to this chamber 37 to check the operating pressure.

As soon as the pressure reaches a given value, which may be adjustable by usual means for regulating the switch 34, said switch opens the circuit of the motor 17 and stops the operation.

When the pressure has fallen owing to part of the juice flowing from the cake, the circuit of the motor 17 automatically closes by the reverse operation of the switch, until the disconnecting pressure is again reached, and so on.

By reversing the reversing switch 33, the direction of supply of the motor is reversed and the plates are moved apart, and the expressing operation can be recommenced if necessary, this being done as many times as necessary.

Another modification is shown in Fig. 8, in which the fluid tight constant. volume chamber is of greatly redimensions and is intended solely to eifect a'utomatic opera on of the switch inaccordance witlitli'e' ex pressing pressure. According to this statesm n; the flui tightf chamber, is forined' on the central non-threaded por I '44 of the axial screw 5 the combination of two Iings' l S and 4 6,"'whicli are" fixed in' 'a" fluid-tight manner finjsaid portion 44, 'ancla short hovering 47 6f rubber orlike elastic" material, which is damped in a fluid-tight manner on said rings by two clamping' riiigs 48 and 49.

As in the first example, the interior of the chamber thus formed is connected by the radial hole 42 and the axial passage 41 to the chamber 37 closed by the diaphragm 36, which actuates the push member 35 controlling the switch 34 controlling the power supply to the motor 17.

Although specific embodiments of the invention have been described, many changes and modifications may be made therein without departing from the scope of the invention as defined in the appended claims.

It will be seen that if necessary there may be disposed in the space which receives the product to be expressed, a conventional device which has break-up chains and hoops and is intended to dislocate the more or less compact cakes obtained at the end of each compression period.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. A press for extracting a liquid from a product to be pressed, said press comprising a frame, an axial horizontal screw fixedly mounted in said frame and having two oppositely screw-threaded portions and two smooth end portions, a horizontally disposed cylindrical screen rotatably mounted on said smooth portions of said screw, an electromechanical device for rotationally driving said screen about the axis of said screw, two plates slidably keyed in said screen, said plates including first nuts screw-threadedly mounted on said screwthreaded portions of said screw, and a deformable core of constant volume disposed around said screw between said plates, said core being defined by two end pieces which form fluid-tight second nuts on said screw and an interposed tubular sleeve of elastic deformable material fixed in a fluid-tight manner on said end pieces to define an annular chamber around said screw and a liquid continuously confined in and filling said annular chamber, and connecting means connecting said end pieces to said plates for rotational movement with said plates while maintaining said end pieces axially spaced from said plates in a direction parallel with said screw, whereby when said plates are moved toward one another upon rotation of said screen said sleeve assumes substantially the form of a truncated double cone which is urged radially into the product to be pressed and facilitates the pressing of said product, said annular space within said sleeve varying in shape but remaining unvaried in volume throughout the cycle of operation of the press.

2. A press as claimed in claim 1, wherein said plates have hubs which form said first nuts and said connecting means are formed by sleeves connecting said end pieces to said hubs, said sleeves being provided with holes to permit the liquid extracted from the product being pressed to lubricate said first nuts.

3. A press as claimed in claim 1, further comprising an electric power supply circuit for said electromechanical device, an electric switch disposed in said electric power supply circuit, a hydraulic device for actuating said switch, and a passageway provided in said screw and connecting said hydraulic device to the inside of said sleeve whereby said switch is opened and said electromechanical device ceases to operate when a given pressure prevails in said core and said switch is once more closed when a pressure lower than said given pressure prevails in said core.

. 7 i l 4. A press as claimed in claim 3, wherein said hydraulic device comprises a chamber closed by a movable member connected to a push member operatively connected to the switch, said chamber being connected by said passageway to said annular chamber of said core.

5. A press as defined in claim 1 further comprising means for actuating said electromechanical device in response to variations in the pressure of said liquid in said chamber.

References Cited in the file of this patent UNITED STATES PATENTS Whittington Aug. 3, 1954 FOREIGN PATENTS France Dec. 23, 1953 France May 6, 1954

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