Abstract:
The object of the invention is to provide a chamber for a heating press which can cope well with the height change of a composite material article. In a chamber for a heating press, upper and lower metal flanges  6, 7  are provided between upper and lower press heating plates  1, 2  and an intrusion part  11  is further formed in the lower metal flange. This intrusion part  11  is intruded into the upper metal flange  6  and the gap between the intrusion part  11  and the upper metal flange  6  is sealed by a packing  22  having a lip.

Description:
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT 
     1. Field of the Invention 
     The present invention relates to a movable vacuum forming apparatus used in a press machine for molding a laminated plate, rubber or resin and capable of forming a vacuum space which can deal with a dimensional change in a pressing direction. 
     2. Prior Art 
     A press apparatus or a heated press apparatus has been conventionally used widely in laminating, press-contacting or molding plate, powder, fiber, foil or the like of organic substance, inorganic substance, metal or the like or composite materials of these or in rubber molding, resin molding or the like. 
     According to such a press apparatus, when it is intended to increase an adherence degree of a work or remove remaining gas bubbles, pressing needs to carry out in a vacuum state. Further, when heating is needed in laminating or molding a work, pressing in a vacuum state is similarly needed in order to increase an adherence degree or a density by preventing gas bubbles produced by heating from remaining, preventing insulation failure by remaining gas bubbles in electronic parts or the like, or preventing wiring patterns from being oxidized by oxygen in the atmosphere. 
     In order to achieve the above-described object, according to a conventional press apparatus, a hermetically-sealed space is formed by providing a single piece of cylindrical body between upper and lower press plates. Further, packings made of synthetic rubber are interposed between the upper and lower press plates and upper and lower ends of the cylindrical body and the packings are made to follow movement in the up and down direction by pressing and a change in a height of a fabricated composite material within a range of elasticity of rubber. 
     OBJECT OF THE INVENTION 
     However, according to such a conventional constitution, there is provided only follow-up performance within a range of elasticity of the synthetic rubber and therefore, there poses a problem that an exclusive cylindrical body having a different height must be fabricated to deal with a small difference in the height of the work or a variation in the height. Further, since the cylindrically body is directly applied with compression load of pressing, there poses a problem that deformation or destruction of the cylindrical body is liable to cause. 
     Further, there also is a vacuum press machine of a house type confining a total of the press apparatus in a vacuum chamber, in this case, there pose problems that the cost is high, the installation space is large, time is taken for vacuuming when the volume of the vacuum chamber is large, the maintenance is laborious, or a conventional general purpose open press machine cannot be diverted thereto. 
     It is an object of the invention to improve the above-described drawbacks of the conventional technology. 
     SUMMARY OF THE INVENTION 
     In order to achieve the above-described object, according to an aspect of the invention, there is provided a movable vacuum forming apparatus comprising a pair of frames provided between upper and lower press plates of a press apparatus and provided to respectives of the upper and the lower press plates via packings for surrounding a predetermined space, an interpenetrated portion provided at one of the frames and capable of being interpenetrated into other of the frames movably in an up and down direction, a seal apparatus for slidably sealing an interval between the interpenetrated portion and the other of the frames, and a sucking apparatus for bringing a space surrounded by the interpenetrated portion and the other of the frames under a negative pressure, wherein the seal apparatus seals the interval by compensating for a strain of the interpenetrated portion caused by the negative pressure of the space. 
     It is preferable that the seal apparatus is a packing mounted to the interpenetrated portion and brought into sliding contact with an inner periphery of the other frame and includes a lip having a size in correspondence with the strain of the interpenetrated portion. Further, the seal apparatus may be a packing mounted to a side of the other frame and brought into sliding contact with an outer periphery of the interpenetrated portion. 
     According to the above-described constitution, the space formed by the frames can be expanded and contracted in the up and down direction and accordingly, can follow to a height of a work. Therefore, it is not necessary to prepare frames for respective height of the work. Further, the apparatus does not directly undergo press load and therefore, deformation or destruction thereof can be prevented. Further, the apparatus can effectively correspond to the strain caused by the negative pressure of the interpenetrated portion to thereby maintain the sealing function. 
     Further, there are achieved advantages that the apparatus can simply be attached to a conventional general purpose open press machine, a time period required for vacuuming is short since a volume of a vacuum chamber is necessary minimum in comparison with that of a house type vacuum press machine, the cost is low and so on. 
    
    
     BRIEF DESCRIPTION OF THE DESCRIPTION 
     FIG. 1 is a schematic side sectional view for explaining an embodiment of the invention, showing a state in which a pair of frames are expanded from each other; 
     FIG. 2 is a schematic side sectional view for explaining the embodiment of the invention, showing a state in which the pair of frames are compressed to each other; 
     FIG. 3 is an enlarged side view of a packing  22  according to the embodiment of the invention; 
     FIG. 4 is a plane view of an outlook of the embodiment of the invention; 
     FIG. 5 is a schematic sectional view for explaining other embodiment of the invention, showing a state in which a pair of frames are expanded from each other; 
     FIG. 6 is a schematic side sectional view for explaining the embodiment of the invention, showing a state in which the pair of frames are compressed to each other; 
     FIG. 7 is a plane view of an outlook of the embodiment of the invention; 
     FIG. 8 is a schematic side sectional view for explaining still other embodiment of the invention, showing a state in which a frame and a base are expanded from each other; 
     FIG. 9 is a schematic side sectional view for explaining the embodiment of the invention, showing a state in which the frame and the base are compressed to each other; and 
     FIG. 10 is a plane view of an outlook of the embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     An explanation will be given as follows of an embodiment of the invention in reference to the drawings. 
     Embodiment 1 
     FIG. 1, FIG. 2, FIG.  3  and FIG. 4 show an embodiment of the invention. 
     A shape of a movable vacuum forming apparatus X according to the invention is constituted by a quadrangular shape in conformity with a shape of a work W to thereby promote a space efficiency. The space can be a round shape or other shape when there is allowance in an area of a press plate. 
     According to the embodiment, an upper frame  6  and a lower frame  7  are provided between an upper press plate  1  and a lower press plate  2  and the work W is enclosed at inside of a hermetically-sealed space R formed thereby. The upper frame  6  and the lower frame  7  are formed by a square shape, an interval between the upper frame  6  and the upper press plate  1  are sealed by a packing  20  and an interval between the lower frame  7  and the lower press plate  2  is similarly sealed by a packing  21 . 
     An upper end side of the lower frame  7  is integrally formed with an interpenetrated portion  11  having a small outer diameter and the portion of the interpenetrated portion  11  is constituted to interpenetrate inside of the upper frame  6 . 
     A packing  22  in a ring-like shape is mounted between an outer periphery of the interpenetrated portion  11  and an inner peripheral face of the upper frame  6  to thereby constitute to seal an interval between the interpenetrated portion  11  and the upper frame  6 . 
     Further, numeral  9  designates a spring for pressing the upper and the lower frames  6  and  7  respectively to the upper and the lower press plates  1  and  2 . 
     The upper frame  6  and the lower frame  7  are connected movably in the up and down direction by a set plate  10  and a maximum height is restricted thereby. 
     As shown by FIG. 4, a plurality of the set plates  10  are provided in the peripheral direction and integrate the upper frame  6  and the lower frame  7 . 
     The set plate  10  is constituted by a plate  30  mounted to the lower frame  7  and a pin  32  fixed to a side of the upper frame  6 . The plate  30  is formed with a long hole  31  with which the pin  32  is engaged and the upper frame  6  and the lower frame  7  are integrated movably in the up and down direction by a movable amount h. 
     By the above-described constitution, the movable vacuum forming apparatus X can be handled integrally as a single body. 
     As described above, the hermetically-sealed space R at inside of the movable vacuum forming apparatus X is brought into a vacuum state and at that occasion, strain may be caused at the interpenetrated portion  11  in an inner side direction by the atmospheric pressure. Particularly, when the movable vacuum forming apparatus X is in the quadrangular shape, the strain is enlarged at a vicinity of a central portion of a side of a straight line. There is a danger of constituting sealing failure by opening a clearance between the interpenetrated portion  11  and the upper frame  6  by the strain of the interpenetrated portion  11 . 
     Therefore, according to the invention, the packing  22  is provided with a function of compensating for the strain. 
     That is, as shown by FIG. 3, the packing  22  in the ring-like shape is constituted by a main body  23  in a ring-like shape and a lip  24  in a ring-like shape. The main body  23  is fitted to a groove  12  formed in the interpenetrated portion  11  and the lip  24  is projected from the main body  23  in a direction of the inner peripheral face of the upper frame  6  and is brought into contact with the inner peripheral face of the upper frame  6  to thereby seal the clearance. 
     Further, the packing  22  may be mounted to the side of the upper frame  6  to thereby bring the lip  24  in contact with an outer peripheral side of the interpenetrated portion  11  and seal the clearance. 
     The lip  24  is constituted by a flexible material and is provided with a length to sufficiently be brought into contact with the upper frame  6  and seal the clearance even when the clearance G between the upper frame  6  and the interpenetrated portion  11  is opened. Further, as shown by FIG. 3, the lip  24  is inclined to a lower side and is pressed to the inner peripheral face of the upper frame  6  by pressure from the side of the atmosphere in addition to the flexibility to thereby achieve high sealing performance. Dotted lines in the drawing indicate a position of the lip  24  in a natural state, the lip  24  is flexed by being brought into contact with the inner peripheral face of the upper frame  6 , adhered to the inner peripheral face of the upper frame  6  and at the same time, pressed to the inner peripheral face of the upper frame  6  by the atmospheric pressure. 
     A short lip  25  in a ring-like shape is provided to prevent the lip  24  from not being brought into contact with the inner peripheral face of the upper frame  6  by entering the groove  12 . Further, a cavity portion  26  is formed in a ring-like shape at a vicinity of a center of the packing  22  to thereby provide elasticity and facilitate insertion of the packing  22  into the groove  12 . 
     Further, the main body  23  is formed by a square shape to thereby prevent twist or the like even when the lip  24  undergoes pressure or friction. 
     According to the above-described constitution of the packing  22 , even when inside of the movable vacuum forming apparatus X is brought into the vacuum state, strain is caused at the interpenetrated portion  11  and the clearance G is enlarged, contact of the lip  24  with the upper frame  6  is not interrupted and the excellent sealing state is continued. 
     Further, in FIG. 1, the lower frame  7  is provided with a suction hole  8  to thereby bring the inside of the apparatus into the vacuum state. Further, nozzles may be provided for measuring pressure and temperature and in order to connect the nozzles, as shown by FIG. 4, a pressure meter hole  51 , a thermocouple hole  52  and the like are provided. 
     Further, in place of the packings  20  and  21 , the packings such as  0  rings or the like can also be used. 
     According to the above-described constitution, the upper frame  6  and the lower frame  7  are made of metal and are movable in the up and down direction in the range of the movable amount h and therefore, can follow a change in the height of the work W. The movable range can be made an arbitrary magnitude by changing the height of the interpenetrated portion  11  or the height of the upper frame  6  and by previously estimating the necessary movable range in correspondence with the change in the height, there is achieved an effect capable of dealing with the change of the height of the work W without replacing the upper frame  6  and the lower frame  7 . 
     Further, even when the inside of the movable vacuum forming apparatus X is brought into the vacuum state and the strain is caused in the interpenetrated portion  11 , the lip  24  of the packing  22  pertinently follows thereto and maintains to seal between the lip  24  and the upper frame  6  and therefore, the excellent sealing performance can be maintained. 
     Embodiment 2 
     FIG. 5, FIG.  6  and FIG. 7 show other embodiment of the invention. Although the basic constitution is similar to that of Embodiment 1, according to the embodiment, the suction hole  8  is provided to the upper frame  6 . 
     When the suction hole  8  is provided on the side of the upper frame  6 , as shown by FIG. 6, the suction hole  8  is closed by the interpenetrated portion  11  in the compressing operation. Therefore, the suction hole  8  is constituted by an L-like shape as illustrated and is made to communicate with a notched groove  13  formed at an upper face of the upper frame  6 . Meanwhile, an upper face of the interpenetrated portion  11  is also formed with a notched groove  14  for connecting to the notched groove  13  to thereby construct a constitution in which the hermetically-sealed space R is vacuumed from the suction hole  8  by way of the notched groove  13  and the notched groove  14 . 
     Further, by constituting the suction hole  8  in the L-like shape, the total height of the movable vacuum forming apparatus X can be lowered, which is effective when a distance between the upper and the lower press plates is short. 
     Embodiment 3 
     FIG. 8, FIG.  9  and FIG. 10 show still other embodiment. 
     According to the embodiment, there is used a base  70  which is not constituted by a shape of a frame in place of the lower frame  7 . 
     Thereby, a height adjusting plate is not put into the hermetically-sealed space R and even when a thickness of the work W is unlimitedly proximate to 0 mm as in pasting or laminating a film, vacuum pressing can be carried out. Further, in this example, the hole  8  is provided to the base  70  in an L-like sectional shape. 
     The base  70  is provided with the packing  21  at a bottom face thereof to thereby seal an interval between the base  70  and the lower press plate  2 . Further, the base  70  is formed with a balance hole  71  to communicate the hermetically-sealed space R and a hermetically-sealed space R′ formed on the bottom face side. This is for preventing the base  70  from being attracted to the upper frame  6  by the hermetically-sealed space R formed in the movable vacuum forming apparatus X. The hermetically-sealed spaces R and R′ are connected by the balance hole  71  and therefore, the same pressure is constituted and the movable vacuum forming apparatus X can be prevented from being automatically contracted by a difference between the pressure and the atmospheric pressure by vacuuming the hermetically-sealed space R to thereby adsorb the base  70  to the upper frame  6 . 
     When it is permitted that the apparatus is automatically contracted and adsorbed to the upper frame  6 , there can be constructed a structure which is not provided with the balance hole  71 . 
     Further, in place of the packings  20  and  21 , packings having other shape such as O rings or the like can also be used. 
     According to the above-described constitution, there are achieved an effect similar to that of Embodiment 1 and an effect of capable of dealing with a work having a thin thickness. 
     Further, any of the movable vacuum forming apparatus X in the embodiments 1, 2 and 3 can be used by constituting multiple stages thereof by building up the apparatus by interposing plates or the like thereamong. Further, in the case of embodiments 1 and 2, the apparatus X can be used by laminating the apparatus without interposing plates thereamong to thereby deal with a work having a large height. 
     As has been explained above, according to the movable vacuum forming apparatus for pressing of the invention, the apparatus can follow the change in the height of the work and it is not necessary to provide frames for respective different heights as in the conventional technology. Further, the frame or the spring is not deformed or destructed by compression load. Further, there is achieved an effect of promoting the sealing performance and enabling to prevent occurrence of failure or the like caused by oxidation which has been caused conventionally. 
     Further, there are achieved advantages that the apparatus can simply be attached to a conventional general purpose open press machine, a time period required for vacuuming or heating is short since the volume of the vacuum chamber is necessary minimum in comparison with that of the house type vacuum press machine, the cost is low and so on.