Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B30—PRESSES
  • B30B—PRESSES IN GENERAL
  • B30B11/00—Presses specially adapted for forming shaped articles from material in particulate or plastic state, e.g. briquetting presses, tabletting presses
  • B30B11/007—Presses specially adapted for forming shaped articles from material in particulate or plastic state, e.g. briquetting presses, tabletting presses using a plurality of pressing members working in different directions

Definitions

• the present invention relates to a device for compressing or compacting bulk products or hollow bodies of the type comprising a compression chamber having a hollow housing intended to receive the product or body to be compressed, at least one movable member which can be engaged in said compression chamber to reduce its volume, means for introducing the product or body to be compressed into the hollow housing and means for extracting the product or compressed body from the latter.
• Such devices are known in particular for compacting industrial waste such as wood and metal shavings or sawdust or wood dust, in order to produce elongated sticks facilitating the storage, handling and transport of this waste for their reuse for example, as fuel elements in the case of wood waste.
• This compression must in almost all cases be carried out without the addition of binders and the increase in density is in this case, considerable.
• sawdust we must go from 30 kg / m 3 to 1200 kg / m 3 , for agricultural compost from about 200 kg / m 3 to 1600 kg / m. and in the case of dehydrated food of around 600 kg / m 3 to 1400 kg / m 3 .
• presses comprising a compression chamber consisting of a hollow housing, most often cylindrical, in which a mobile compression piston is provided. They are thus fixed section devices in which the compression is obtained by a reduction in the length of the hollow housing. For the reasons explained above, these devices work at very high pressures (around 1200 bars) and with high compression rates (around 1/20). In practice, it is then necessary to work in several phases and to use devices with several successive stages of compression. These devices are very complex and expensive. Their automation is difficult and their reliability low. They also include compression chambers of an excessively heavy structure to absorb the high pressures used. Finally, the extraction of the compressed or compacted product is difficult because it is pushed against the walls of the hollow housing and it is brought to employ means of forced extraction.
• the compression chamber consists of an enclosure of regular polygonal section in which is arranged, in the same plane, a series of movable jaws whose number is equal to the number sides of the section of the enclosure and which are each movable in a direction parallel to one of the sides of the section of said enclosure and delimit an interior hollow housing of the same section as said enclosure, the jaws being of a configuration such that when moving at least one of them, the others are also moved.
• Such devices are for example described in the German patent n ° 1 035 352 (BEHR), in the French patent n ° 1 178 560 (HORN) as well as in the English patent n ° 1 588678 (FIAT) and the patent application English No. 2013 554 (FIAT).
• BEHR describes a carpentry press for producing hollow bodies from a mixture of a binder and wood chips or fibers.
• This device is essentially intended to produce hollow joinery elements such as table legs or more particularly boxes for clocks.
• the device comprises in the hollow housing delimited by jaws, a fixed central core.
• the mixture of wood fibers and binder is introduced between the interior faces of the jaws and this core and then the jaws are gradually moved to partially compress the mixture around the core.
• the jaws are each moved by screws ordered separately.
• the mixture to be compressed and the finished product are introduced and released from the press from the same side. It is therefore obviously a device in which the jaws are moved as and. measurement of the compression, one after the other to reach a final position corresponding to the final configuration of the body that one wishes to achieve.
• This patent essentially relates to structures in which only one of the jaws is moved and drives the others against the friction existing between the different jaws (claim 1).
• the French HORN patent describes a device whose general structure corresponds to that of the type described above but in which the mass to be molded is successively subjected to two compression effects effected in directions perpendicular to one another.
• the pressure in the horizontal direction is obtained thanks to. four jaws arranged at.
• the interior of an enclosure and the pressure in the vertical direction is obtained thanks to an upper control plate and a lower compression piston.
• the HORN patent proposes a very particular command of the jaws which consists in providing on the jaws and the corresponding walls of the enclosure conical surfaces so that when the upper plate exerts a pressure on the upper face of the jaws, these are moved down and get closer to each other by compressing the material.
• the punch or lower piston performs: a final compression.
• the configuration of the jaws and of the enclosure to ensure the approximation of the jaws appears to be extremely complex and the friction forces involved to obtain an approximation of the jaws during their descent are very important in this case so that it is considered that, in practice, such a device could not work.
• the English FIAT patents relate to presses for compacting powders or granules.
• the press comprises a square enclosure in which are arranged four identical jaws which delimit by their internal face a hollow housing intended to receive the powders to be compacted.
• the jaws have a configuration such that they can only be moved over a very short distance between an open position and a closed position.
• Such devices can only be used for materials of the same type, that is to say of the same particle size and the same density in order to be able to obtain between the open position and the closed position the compaction longed for.
• the jaws are made up of two parts with different sections ordered separately.
• the control of the two sections of each jaw is obtained by a jack by means of a mechanical linkage which does not allow the movement of the different jaws to be synchronized so that significant friction forces are observed when tightening these past.
• the object of the present invention is to design a device of the latter type, that is to say of the type comprising an enclosure in which are arranged several jaws defining a hollow housing for receiving the material. compress which allows to compress bulk products of different densities without changing the configuration of the jaws and which allows continuous automatic operation of the press.
• the device comprises means for simultaneously controlling and in perfect synchronism the movement of the set of jaws in two opposite directions, parallel to a wall of the enclosure over adjustable distances making it possible, if necessary, to substantially reduce at zero the section in said plane of said hollow housing, movable flaps controlled in a plane parallel to the plane of the jaws being provided to close or release one, the upper loading opening and the other, the lower unloading opening said hollow housing.
• said control means comprise, for each movable jaw, a double-acting hydraulic cylinder whose free end of the rod is connected directly to the jaw to control the movement of the latter , the jacks extending in the plane of the jaws.
• said flaps are also controlled by hydraulic jacks and said jacks are supplied through distributors controlled by cams fixed on the same control shaft.
• the jaws can be brought into an extreme position in which the section of the hollow housing is. Almost zero, we can ensure the compression of materials of very different density and structure for which we are essentially looking for a critical final pressure allowing to obtain a solid body which can be handled and stored without difficulty. In certain applications, this complete closing of the press allows self-cleaning of the internal faces of the jaws.
• the materials to be compressed are introduced into the hollow housing in the open position of the device through the upper loading opening. After the compression phase, the lower flap is released so that the body obtained is automatically ejected through the lower unloading opening without the use of any ejection member.
• the press according to the invention allows the compression of products such as sawdust or wood shavings in a single phase at pressures of the order of 300 to 800 bars which are relatively low compared to cylinder or piston devices. of the prior art used for the compression of the same products.
• enclosures with an isosceles or square triangular section comprising respectively three or four jaws, but other regular polygonal sections can also be used, but in this case, the mounting and control of the jaws becomes more complex.
• the distributors are supplied by a hydraulic pump with variable flow
• the motor for controlling the shaft of the set of cams is a hydraulic motor supplied by a flow regulator from the main outlet of said pump which is adjusted so that the return cycle of the jacks controlling the jaws is not initiated until after a predetermined time after the moment when the outlet pressure of the pump has reached the nominal pressure of the hydraulic circuit of ordered.
• the cam controlling the distributor of the jacks has a circumferential part controlling the compression phase of the jaws which extends over an angle greater than 60 ° of the cam.
• FIGS. 1 and 2 are schematic plan views showing the operating principle of two essential variants of the device according to the invention
• FIG. 3 is a schematic plan view of a preferred embodiment of the device according to the invention
• FIG. 4 is a schematic transverse vertical section view along the line IV-IV of FIG. 3
• FIG. 5 is a schematic view showing in particular the hydraulic control means of the device shown in FIGS. 3 and 4.
• Figures 1 and 2 very schematically show the general structure of two variants of the compression chamber of the device according to the invention.
• This compression chamber consists of a regular polygonal enclosure (1) open at its opposite ends and in which are housed several jaws (2) whose number is equal to the number of sides of the polygon forming the enclosure (1).
• the jaws (2) are movable relative to each other and relative to the corresponding walls of the enclosure and their configuration is such that when they are brought into their extreme outer position their inner walls define a compression channel (3) whose general section corresponds to that of said enclosure (1) and when they are moved towards the center of the enclosure, the section of the channel (3) gradually decreases until the channel (3) disappears.
• the enclosure (1) has a triangular section and has three jaws (2) defining a compression channel also triangular.
• the variant shown in FIG. 2 comprises an enclosure (1) with a square section provided with four jaws (2) delimiting a compression channel (3) also having a square section.
• the jaws (2) are shown in their extreme external position in which the section of the compression channel reaches its greatest value.
• the device according to the invention uses such an arrangement for compressing or compacting bulk materials or hollow bodies.
• Figures 3 and 4 show a first preferred embodiment of the device according to the present invention. He understands, as represented feel at. these figures, a compression channel consisting of an enclosure. square section (1) in which four jaws (2) of the type shown in FIG. 2 are housed.
• each jaw (2) is controlled by a double-acting hydraulic cylinder (V1, V2, V3, V4) respectively.
• V1, V2, V3, V4 The upper and lower ends of the compression channel can be closed off by movable horizontal drawers (4, 5), the movement of which is controlled by hydraulic cylinders (V5, V6) as shown in FIG. 4.
• These cylinders (V5, V6) allow the drawers or shutters (4, 5) to be moved in the direction of the arrows (F5, F6).
• the two drawers (4, 5) are shown in the compression phase in which they close the upper and lower ends of the compression channel.
• the section of the drawers (4, 5) is larger than the largest possible section of the compression channel (3).
• Figure 5 shows the diagram of the hydraulic supply circuits of the different cylinders. (V1 to V6) ensuring perfect synchronization of the movements of the jaws (2) and the drawers (4, 5) during the various phases of the operation of the device according to the invention.
• a debt figure we see a reservoir of hydraulic fluid (6) into which opens, through a strainer (7), the suction pipe (8) of a hydraulic pump (9).
• the discharge port of the pump (9) is connected by a pipe (10) to a first distributor (11) controlling the supply of hydraulic fluid to the jacks (V1 to V3) actuating the jaws (2) of the compression.
• the discharge port of the pump (9) is also connected by pipes not shown here to the inlet ports of a second and third distributors (12, 13) controlling the supply of hydraulic fluid to the cylinders (V5, V6) respectively which actuate the drawers or flaps (4, 5) arranged opposite the upper and lower ends of the compression channel (3).
• the distributors (11, 12, 13) are controlled in a known manner by cams (14, 15, 16) respectively fixed on a common shaft (17) driven by a hydraulic motor (18).
• This motor (18) is connected through a flow regulator (19) to the discharge port of the pump (9).
• In (20) is represented a motor electric driving the pump (9) and eh (21), the common return line of the distributors (11, 12, 13) and of the hydraulic motor (18).
• This pipe (21) comprises in a known manner a fine filter (22).
• a fine filter (22) For reasons of clarity of the drawing, the pipes connecting the inlet and return orifices of the distributors (12 and 13) to the pipes (10 and 21) respectively, are not shown here.
• return springs tending to bring the movable members or drawers (26, 27, 23) of the distributors (11, 12, 13) into their rest position against the action cams (14, 15, 16).
• FIG. 4 does not show the upper and lower walls of the enclosure (1) in which the drawers (4, 5) are supported and guided.
• the table below shows the results obtained with a device according to the invention of the type as shown in Figures 3, 4 and 5 which, in practice, has the following characteristics:
• Compression channel - maximum dimensions before compression: 100 mm X 100 mm;
• the pump (9) is a variable flow pump, that is to say a pump which delivers until the hydraulic circuit of the installation has reaches its nominal pressure and which then only serves to maintain this pressure. Thanks to the fact that the hydraulic motor (18) driving the shaft (17) carrying the three cams (14, 15, 16) is supplied directly from the pump outlet pipe (10) (9), through the flow regulator (19), it can be ensured that by means of a suitable adjustment of this regulator (19), in all cases, the pressure applied at the end of stroke to the cylinders (V1 to V4) is always the nominal pressure of the circuit hydraulic.
• control (14) controlling the drawers controlling the hydraulic supply of the jacks (V1 to V4) has a peripheral part controlling the closing phase of the device which extends over an angle greater than 60 °. of the cam. In this way, in all cases, the nominal pressure of the hydraulic circuit is reached subject to suitable adjustment of the flow regulator which is within the reach of those skilled in the art.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Processing Of Solid Wastes (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9322053

Family Applications (1)

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Family Cites Families (9)

• 1985
  • 1985-08-05 FR FR8512067A patent/FR2585621A1/fr active Pending
• 1986
  • 1986-08-01 EP EP19860904843 patent/EP0265437A1/de not_active Withdrawn
  • 1986-08-01 WO PCT/FR1986/000275 patent/WO1987000793A1/fr unknown

Non-Patent Citations (1)

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