JPH10156491A - Width changeable mold device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shift one pair of short side molds interposed with one pair of long side molds without shifting the whole bodies of one pair of the long side molds while closely contacting between the long and the short side molds and to easily operate by minifying the mechanism needed to the shifting, related to a width changeable mold device used at the time of continuously casting an aluminum or its alloy. SOLUTION: The short side molds 10 horizontally shiftable corresponding to change of the size of the long side direction of a cast slab to be cast and one pair of the long side molds 4 interposed while closely contacting with both ends of the short side molds, are provided and the center part 5 of each long side mold 4 is fixed to an outer frame. This width changeable mold device 1 is the one closely contacting by abutting on both ends of the short side molds 10 which are elastically deformable in the horizontal direction to both end parts 6 and set the inside surface of both end parts 6 to a prescribed position by utilizing the elasticity. Further, a pushing device 20 for pushing each end part 6 of the long side mold 4 to the short side mold 10 and together with a separating device 50 for separating both end parts can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously casting a slab ingot such as aluminum or an aluminum alloy, the mold comprising two sets of long and short sides forming a cavity having a substantially rectangular cross section. In particular, the present invention relates to a variable width mold apparatus capable of changing the dimension of the ingot in the long side direction by moving the short side mold.

[0002]

2. Description of the Related Art In order to manufacture a coil by rolling aluminum or an aluminum alloy (hereinafter simply referred to as aluminum), a rectangular ingot is used. This ingot has various cross-sectional shapes depending on the width of the coil to be rolled. Preparing and using a large number of special molds to obtain these ingots is problematic in terms of productivity and cost, so it is possible to change the dimension of the rectangular cross section in the long side direction (hereinafter referred to as width) Various molds have been proposed.

For example, a variable width mold 200 shown in a plan view in FIG. 9 (A) has a pair of long side molds 202 supported in parallel and movably in a horizontal direction, and a pair of long side molds 202 near both inner ends thereof. Movable pair of short side molds 21
0, and the long side mold 202 is a water cooling jacket 2
This is a hollow body having 04, and slide tubes 206 for water supply are fixed to both ends. The short side mold 210 is also a hollow body having a water-cooled jacket 212, and a slide tube 214 is fixed to an outer surface thereof. Then, the short side molds 210 are moved in a horizontal direction by a screw feed mechanism (not shown) so as to come in contact with and separate from each other. Therefore, the long and short side molds 202 and 210 are adjusted according to the sectional dimensions of the ingot to be cast.
Is moved (JP-A-4-33750).

A variable width mold apparatus 220 shown in a plan view in FIG. 9 (B) is a parallel long piece member of a double mold 221.
(Molds) 222, 224, and a pair of left and right short piece members (Moulds) 225 positioned between them and movable in the left-right direction in the figure.
Consists of Long member 224 of each adjacent mold 221
A plurality of first members 226 having left and right tapered grooves are fixed on the back surface of the first member 226. The second member 228 having a tapered surface inserted into these tapered grooves is screwed into a screw portion of the rotating shaft 230, and the rotating shaft 230 is rotated by a handle shaft 234 provided on the outer frame 232. You. Then, when the handle shaft 234 is turned to rotate the rotary shaft 230, each second member 228 screwed thereto slides in the left-right direction. Accordingly, each first member 226 becomes a second member 228.
The long piece member 224 is moved in the direction of the vertical arrow shown in the figure by the sliding action of the tapered surface of (a) to enable the movement of each short piece member 225 and the close contact of the long and short piece members (Japanese Patent Laid-Open No. 7-15591).
0).

[0005]

When the width of the ingot is changed, the variable width mold 200 moves at least one of the long side molds 2 to move the short side mold 210 to a predetermined position.
02 is required to be shifted. Also, in the variable width casting mold 220, in order to move the short piece member 225, an operation of shifting the whole of the movable long piece member 224 by the taper action of the first member 226 and the second member 228 is required.

In each of the above techniques, the long side mold 20
2 and the entire long piece member 224 must be displaced. Since these require rigidity and are made of a long and heavy metal member, the long side mold 202 and the long piece member 224 need only be several mm in length.
It requires a durable mechanism and guide with great force to shift to the extent. For this reason, there was a problem that the structure of the mold device was enlarged and complicated. In addition, when a plurality of mold devices are installed adjacent to each other, a mechanism or a guide for the shifting operation is provided between the adjacent mold devices, which is uneconomical in terms of layout. The present invention solves the problems involved in the conventional technology as described above, makes it possible to easily move the short-side mold without shifting the entire long-side mold, reduces the size of the mechanism required for these, and makes the operation simple. It is an object of the present invention to provide a variable width mold device that can be used.

[0007]

According to the present invention, in order to solve the above-mentioned problems, a central portion of a long side mold is fixed to an outer frame supporting long and short side molds, and both ends thereof are elastically deformable. This is obtained by using the elastic deformation to move the short side mold and bring the long and short side molds into close contact with each other.

That is, the variable width mold apparatus of the present invention comprises a pair of short side molds movable in the horizontal direction in response to a change in the dimension of the ingot to be cast in the long side direction, and both ends of these short side molds. A pair of long-side molds that are closely held in close contact with each other, a central portion of each long-side mold is fixed to an outer frame, and both ends of the long-side mold are elastically deformable in a horizontal direction, and these two end portions are The inner side surface is brought into close contact with both ends of a short-side mold set at a predetermined position by utilizing its elastic deformation. In this way, since the long side mold is fixed so that only the both ends can be elastically deformed, when the short side mold is moved or the long and short side molds are brought into close contact, only the both ends need to be elastically deformed. .

In order to maintain the close contact between the long and short sides of the mold, the ends of the long sides of the short sides of the short sides of the short side mold are elastically deformed. A variable width mold device provided with a pressing device that is brought into close contact with both ends is also included. The above-mentioned pressing device is a protruding portion that straddles above or below the end of the long side mold opposite to both ends of each short side mold,
The cam mechanism, link mechanism,
It consists of any of a screw feed mechanism, a pantograph mechanism, or a hydraulic cylinder. According to this pressing device, the short side mold and each of the above mechanisms are unitized via the protruding portion, and the operability is also facilitated.

The pressing device is separate from the short side mold, and is movably mounted on an outer frame adjacent to an end of the long side mold, a link mechanism, a screw feed mechanism, and a pantograph mechanism. Or any of the hydraulic cylinders. Furthermore, the present invention also includes a variable width mold device provided with a contact / separation device for separating the opposite end portions of the pair of long side molds by elastic deformation when moving each of the short side molds. As the contact / separation device, any one of a link mechanism, a cam mechanism, a reverse screw feed mechanism, a pantograph mechanism, or a hydraulic cylinder is used. According to this contacting / separating device, while the short-side mold moves, the ends of the long-side molds can be elastically deformed with a small force and the gap therebetween can be increased by several mm, so that the short-side mold can be easily operated. can do.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a plan view of a variable width mold apparatus 1 of the present invention, in which a substantially rectangular ingot casting hole 2a is formed on an outer frame 2 supporting the following long and short side molds 4 and 10. And a pair of short side molds 10 located at both ends between them and opposed to each other.
Having. Each of the long side molds 4 has an elongated thin plate shape made of an aluminum alloy, and has a central portion 5 having a slightly outwardly bowed center.
And elastically deformable ends 6 (hatched portions in the figure) at both ends. This central portion 5 is vertically fixed on the outer frame 2 along the side edge of the ingot pouring hole 2a. Further, the bow shape of the central portion 5 is for preventing and compensating for the dent deformation which occurs on the long side due to the difference in shrinkage due to the difference in cooling rate between the portions when the ingot solidifies. In addition, the short side mold 10
Is made of an aluminum alloy like the long side mold 4 and comprises a substantially rectangular parallelepiped main body 12 and contact pieces 14 fixed to both ends thereof, and can be moved in the direction of the arrow in the figure as described later. I have. The contact piece 14 is replaced when its end is worn, but may be replaced with a piece integrated with the main body 12.

On both left and right sides of each short side mold 10, a pressing device 20 is located with the end 6 of the long side mold 4 interposed therebetween. These pressing devices 20 are connected to the short side mold 10 via a projecting portion which will be described below and extends below the long side mold 4 provided at the end of the short side mold 10. The pressing device 20 contacts the end portion 6 of the long side mold 4 with the close contact piece 14 of the short side mold 10 by a cam mechanism described later. In addition, contacting / separating devices 50 are respectively provided on the outer frames 2 between the plates 8 fixed to the outermost ends of both ends 6 of each long side mold 4. These contacting / separating devices 50 abut both ends of the plate 8 that extend and contract to separate the opposite end portions 6 of the pair of long side molds 4 from each other.

That is, when the position of the short side mold 10 is changed, as shown in FIG. 2A, first, the close contact between the long side mold 4 and the short side mold 10 by the pressing device 20 is released. As a result, the elastically deformable end 6 returns to the vicinity of the outer free position. Next, both ends of the contact / separation device 50 are extended and brought into contact with the plate 8 to separate the opposite ends 6 of the long side mold 4 from each other outward. Then, since the contact piece 14 is separated from the long-side mold 4, the short-side mold 10 easily moves in the direction of the arrow and is moved to a desired position. Next, as shown in FIG. 2B, both ends of the contact / separation device 50 are retracted and separated from the plate 8. Then
The end portions 6 of the long side mold 4 return to the vicinity of the free positions.
Finally, when the end 6 of the long side mold 4 is pushed inward by the pressing device 20, each end 6 is elastically deformed and comes into contact with the contact piece 14 of the short side mold 10 to be in a close contact state. Are defined. The above operation utilizes the elastic deformation of both ends 6 of the long side mold 4. In addition, long side mold 4
The free position of the elastically deformable end portion 6 is slightly outside the position where the long and short side molds 4 and 10 are in close contact with each other during casting by a distance pressed inward from the zero by a few mm by the pressing device 20. .

Next, the details of the contact / separation device 50 will be described with reference to FIG. The contact / separation device 50 includes a substantially rhombus-shaped rotating plate 54 rotatably supported via a rotating shaft 56 between a pair of brackets 52 at the center of the base 3 on the outer frame 2. A pair of links 60 symmetrically connected from the left and right via pins 58, a push rod 64 that passes through a horizontal sleeve guide 62 provided symmetrically on the base 3,
It comprises a pair of pushers 66 which are screwed to the ends of these push rods 64. Each link 60 and push rod 64
Are also connected to each other by a pin 61.

In order to change the position of the short side mold 10, the close contact between the long side mold 4 and the short side mold 10 by the pressing devices 20 on both sides is released in advance, and each end 6 of the long side mold 4 is removed. Return to near the free position. Next, the lever 5
5, the rotating plate 54 is rotated and the left and right links 60 are moved in the left and right directions, and the left and right push rods 64 and the pushers 66 are also pushed outward along with them, and the state shown in FIG. , And pushes the plate 8 against which each pusher 66 abuts outward. Then, each end portion 6 of the long side mold 4 is elastically deformed and spreads outward and apart from each other. As a result, the short side mold 10 can be easily moved to a new position because the contact piece 14 is separated from each end 6 of the long side mold 4 on both sides. Then, when the lever 55 of the rotating plate 54 is pushed down horizontally, the left and right links 60 move obliquely toward the center, and the left and right push rods 64 and the pushers 66 also move toward the center along with them. Is separated from the plate 8. That is, in order to facilitate movement of the short side mold 10, the contact / separation device 50 temporarily separates the short side mold 10 from each end 6 of the long side mold 4 only during the movement.

Next, details of the pressing device 20 will be described with reference to FIGS. As shown in FIG. 4, projecting portions 22 are fixed to both ends of the outer surface of the main body 12 of each short side mold 10, and these projecting portions 22 straddle under each end 6 of the long side mold 4. It extends horizontally outside the end 6. The tips of these projections 22 are connected to the side surfaces of an elongated carriage 25 that runs on a channel-shaped rail 24 fixed on the outer frame 2. The carriage 25 is supported on a horizontal piece of the rail 24 so as to be able to travel freely by wheels 26 vertically attached to both ends, and is guided by the vertical piece of the rail 24 by a horizontal wheel 27 attached to an intermediate portion of the bottom surface. . Trolley 2
On a cylinder 28 at the rear end of 5, via a vertical axis 29,
An arm 30 parallel to the carriage 25 is horizontally connected.
A cam mechanism 32 is provided at the tip of the arm 30. A guide 31 parallel to the arm 30 is fixed on the outer frame 2 outside the arm 30. Accordingly, each short side mold 10 can be moved together with the pressing device 20 by the carts 25 on both sides.

As shown in FIG. 5A, the cam mechanism 32
The arm 30 is supported by the arm 30 by vertically penetrating the rotation shaft 36 of the handle 34 on the upper surface of the arm 30 into the slit-shaped recess 38. A horizontal roller 40 whose center is eccentric toward the guide 31 by about several mm is fixed to the rotating shaft 36, and its peripheral surface is in contact with the side surface of the guide 31. The rotating shaft 36 has a substantially triangular shape and a pressing piece 44 at one end.
Is fitted and rotatably supported. A nut 45 is fixed to the other end of the pressing plate 42, and a bolt 46 screwed to the nut 45 is penetrated and supported. The tip of this bolt 46 is
9 comes into contact with the round piece 48 located on the disc spring 47. Therefore, the pressing plate 42 has the rotating shaft 36 as a fulcrum, the other end bolt 46 is urged in the counterclockwise direction by the spring 47 in the drawing, and the pressing portion 44 at one end connects each end 6 of the long side mold 4. By pressing from the outside, the inner surface of each end 6 is brought into close contact with each contact piece 14 of the short side mold 10. As a result, the long and short side molds 4, 1
0 are in close contact with each other, and are ready for casting.

On the other hand, when the position of the short side mold 10 is moved, as shown in FIG. 5B, the handle 34 is turned 90 degrees to the left. At the same time, the contact surface of the roller 40 eccentric to the rotating shaft 36 with the guide 31 is changed from the long diameter portion to the short diameter portion, and the rotating shaft 36 can be moved to the guide 31 side by several mm. Due to the restoring force due to the elasticity of the end portion 6 and the elastic force of the spring 47 at the other end of the pressing plate 42, from zero to several mm
Move to guide 31 side. At this time, the biasing force of the spring 47 in the counterclockwise direction is somewhat released, and substantially balances the outward force due to the elasticity of the end 6 of the long side mold 4. Next, in order to secure a gap for moving the short side mold 10 between the respective end portions 6 of the long side mold 4, the end portions 6 of the long side mold 4 facing each other are separated by the contact / separation device 50. I do. It is preferable that the separation width is equal to or less than the eccentric distance of the roller 40 that is eccentric across the operating range of the pressing device 20 and is a width that causes movement in the long side direction. By these operations, the short side mold 10 and each pressing device 20 connected thereto can be moved in the direction along the long side mold 4, and moved to a position corresponding to the size of the ingot of the next casting lot. Is reset. In order to bring the short side mold 10 and the end 6 of the long side mold 4 into close contact with each other, the lever 55 of the rotating plate 54 of the contact / separation device 50 is pushed down horizontally and the handle 34 is turned in the opposite direction. 5 (A).

According to the variable width mold apparatus 1 as described above,
The long side mold 4 only slightly deforms both ends 6 elastically, and the close contact of the long and short side molds 4 and 10 and the movement of the short side mold 10 can be easily and easily operated by the pressing device 20 and the contact / separation device 50. Can be done quickly. Further, since only the central portion 5 of the long side mold 4 is fixed, a thinner and lighter member can be used as compared with the conventional one, and the force required for the pressing device 20 and the contact / separation device 50 can be reduced, and they can be downsized. Together with the chief
The space around the short molds 4 and 10 can be effectively used.

The present invention is not limited to the above embodiment. FIG. 6 is a partial plan view of the variable width mold apparatus 1 having a different form from the above, and a plurality of mold apparatuses 1 are continuously provided. Then, the end 6 of each long side mold 4 between the adjacent mold devices 1 is shared by a single pressing device 20, and the pressing device 20 is configured by the same cam mechanism as that of the contact / separation device 50. It was done. In this case, the pressing device 20 may be set on, for example, a bogie (not shown) so as to be movable between the mold devices 1 in the direction along the long side molds 4. According to such a configuration, the number of the pressing devices 20 can be reduced, and
And the contact / separation device 50 can be constituted by the same mechanism, so that the operation is easy and the equipment cost can be reduced.

FIG. 7 shows another embodiment of the contact / separation device.
(A) The contact / separation device 80 is based on a reverse screw feed mechanism.
A pair of sleeve guides 82 is provided on the left and right sides of the base 3 on the outer frame 2, and the bolts 84, 84 whose screw directions are opposite to each other penetrate and are slidably supported. Each of the bolts 84 is connected via a nut body 86 that screw-connects the center end thereof, and has pushers 88 attached to the left and right ends. When the handle 87 of the nut body 86 is turned, the bolts 84 are separated from each other to the left and right, and the plate 8 is pushed outward by pushers 88 at both ends, and each end 6 of the long side mold 4 is connected to the short side mold 10.
Of the short side mold 10 can be moved.

FIG. 7 (B) shows a contact / separation device 90 using a cam mechanism.
2 are supported horizontally, and a compressed coil spring 93 is wound around the center of each rod 92, and has a contact portion 94 at the center end and pushers 98 at both ends. An elliptical cam plate 96 is rotatably supported by a shaft 97 between the contact portions 94, and the contact portions 94 are pressed against the peripheral surface of the cam plate 96 by the springs 93. When the rotating shaft 97 is turned 90 degrees by a handle or the like (not shown), the cam plate 96 makes the long diameter portion horizontal, moves each rod 92 in the left and right direction against the spring pressure, and pushes the plate 8 with the pusher 98 at the tip.
To the outside to enlarge the space between the left and right ends 6.

FIG. 7C shows a contact / separation device 100 using a pantograph mechanism.
The rod 102 is horizontally penetrated and supported therein, and has pushers 109 at both ends thereof. A fixed body 103 is fixed to the center of the base 3 on the outer frame 2, and a nut body 106 is screwed to the middle of a vertical bolt 104 whose lower end is rotatably supported. A handle 10 is provided at the upper end of the bolt 104.
5 is fixed. Further, the fixed body 103 and the nut body 106
Symmetrically, four links 107 extend to both sides in a diamond shape via pins, and are connected by pins to a vertical plate 108 fixed to the center side of the rod 102. When the handle 105 is turned and the bolt 104 is rotated to lower the nut body 106 as shown in FIG.
Numeral 7 approaches the horizontal posture, moves each rod 102 in the left-right direction via the vertical plate 108, pushes the plate 8 outward with the pushers 109 at both ends, and enlarges the space between the left and right end portions 6.

In addition to the above, for example, a pinion is fixed to a rotating shaft on the center of the base 3 on the outer frame 2, and a pair of horizontal racks are engaged with upper and lower teeth of the pinion. Such as ones having pushers at both left and right ends, and ones having a pair of fluid pressure cylinders such as air or oil fixed on the base 3 in opposite directions to each other and having pushers at the ends of the respective piston rods. Can be employed.

FIG. 8 shows a pressing device other than the pressing device 20. The pressing device 110 shown in FIG. 3A fixes a nut 114 to a support plate 112 which is vertically fixed on the carriage 25, and supports a bolt 116 which is screwed to the nut 114 and penetrates the support plate 112. The tip part 118 of the bolt 116 is brought into contact with the end part 6 of the long side mold 4. When the bolt 116 is rotated and advanced upward in the figure, the end 6 can be brought into close contact with the short side mold 10 side. On the opposite side of the support plate 112 from the end 6, the horizontal wheels 27 of the carriage 25 contact the guide 31 to support the reaction force against the pressing force of the end 6. It is desirable to fix a handle or the like to the bolt head of the bolt 116.

The pressing device 120 shown in FIG. 8B is similar to the above-described supporting plate 122 fixed vertically on the carriage 25.
A small-sized hydraulic cylinder 124 is fixed to the inner surface of the cylinder, and the tip 128 of the piston rod 126 is brought into contact with the end 6 of the long side mold 4. According to the device 120, only the operation of supplying a fluid such as oil to the cylinder 124 can be performed.
This device 120 can be driven, and remote operation is also facilitated.

Further, the pressing device 130 shown in FIG. 8C has a fixed body 133 provided on the inner surface of a support plate 132 fixed vertically on the carriage 25, and the nut body 1 is connected by four links 134.
35 is provided with a pantograph mechanism including a bolt 137 that is connected to the rotation support 136 and the contact member 139 on the distal end side with a pin, and is supported at the distal end by the rotation support 136 and is screwed to the nut 135. When the bolt 137 is rotated by turning the illustrated handle 138, the nut body 135 moves to the left to bring each link 134 closer to the vertical posture, and the contact body 1
39 is moved upward to bring the end 6 into close contact with the short side mold 10 side.

The pressing devices 110 to 130 described above are used.
Are connected to the short side mold 10 via the protruding portion 22, but the connecting portion to the short side mold 10 is
May be straddled above the end portion 6. Also,
The pressing device is not limited to the one that is necessarily connected to the short side mold 10, but may be a separate carriage that moves in accordance with the movement of the short side mold 10, and may be one in which each of the mechanism units is mounted on this carriage. . For example, it is possible to drive a carriage-side moving motor or the like in accordance with an encoder that rotates as the short-side mold 10 moves. Further, the pair of short-side molds 10 may be synchronously and symmetrically moved to the center or the outside, or only one of the short-side molds 10 may be moved. In these cases, the separate cart can be similarly moved. In addition, when a plurality of mold devices are provided in parallel, the position of each short-side mold for each casting lot is input in advance to the recording unit, and the computer moves each short-side mold to a predetermined position for each lot. Can also be performed.
In addition, this mold device is not limited to aluminum, various steel, alloy steel,
Alternatively, the present invention can be applied to continuous casting of non-ferrous metals such as copper, Ti and W, and alloys thereof, and can be implemented by appropriately selecting the material of the long and short side molds, the lubricating oil, and the cooling method.

[0029]

According to the variable width mold of the present invention described above, only the both ends of the long side mold are shifted by utilizing the elastic deformation thereof, so that the short side mold can be easily moved and the predetermined position can be adjusted. After setting the mold, the close contact between the long and short side molds is ensured, and an ingot having a desired cross-sectional dimension can be easily cast. Also, since the central part of the long side mold is fixed,
The members constituting the mold can be made thin and the surrounding space can be effectively utilized. Further, according to the invention using the pressing device according to claims 2 to 4, the short side mold can be easily and quickly adhered to the predetermined position between the pair of long side molds, such an operation requires a small force, and the pressing device is also used. It can be downsized.
Furthermore, according to the invention using the contacting / separating device of claims 5 and 6, both ends of the pair of long side molds can be quickly and easily spread with a small force, and the movement of the short side mold can be facilitated. .

[Brief description of the drawings]

FIG. 1 is a plan view of one embodiment of a variable width mold apparatus according to the present invention.

2A and 2B are partially enlarged views of FIG. 1;

FIG. 3 is a perspective view showing a contact / separation device used in the present invention and its periphery.

FIG. 4 is a perspective view showing a pressing device used in the present invention and its periphery.

FIGS. 5A and 5B are partially enlarged views of a cam mechanism of a pressing device used in the present invention.

FIG. 6 is a partial plan view showing a different form of the variable width casting apparatus of the present invention.

7 (A) to 7 (C) are side views of different forms of the contact / separation device used in the present invention.

8 (A) to 8 (C) are plan views showing different forms of the pressing device used in the present invention.

9 (A) and 9 (B) are schematic plan views of respective molds showing a conventional technique.

[Explanation of symbols]

 1 ………………………………………………………………………………………………………………………………………………………………………………………. ………………………………………………………………………………………………………. … Ends (both ends) 10 …………………… Short side molds 20,110,120,130 ……… Pressing device (mechanism) 22 ………… ……………………………………………………………………………………………………… Cam mechanism 50,80,90,100

Claims (6)

[Claims] 1. A pair of short-side molds movable in a horizontal direction in response to a change in the dimension of the ingot to be cast in the long-side direction, and a pair of long-side molds closely held at both ends of these short-side molds. Side molds, the central part of each long side mold is fixed to the outer frame, and both ends of the long side mold can be elastically deformed in the horizontal direction, and the inner side surfaces of these both ends use the elastic deformation. A variable width mold apparatus characterized in that both ends of the short side mold set at a predetermined position are brought into contact with and brought into close contact with each other. 2. The apparatus according to claim 1, wherein at both ends of each of said short side molds, a pressing device is provided for bringing both ends of said long side mold into close contact with both ends of said short side mold by utilizing its elastic deformation. Variable width mold device. 3. The projecting device according to claim 1, wherein said pressing device extends from both ends of each short-side mold to above or below an end of the long-side mold opposed thereto, and a cam mechanism and a link mechanism attached to these projecting portions. The variable width mold apparatus according to claim 2, wherein the apparatus is any one of a screw feed mechanism, a pantograph mechanism, and a hydraulic cylinder. 4. A cam mechanism, a link mechanism, a screw feed mechanism, a pantograph mechanism, wherein the pressing device is separate from the short side mold and movably mounted on an outer frame adjacent to an end of the long side mold. The width variable mold device according to claim 2, which is one of a hydraulic cylinder and a hydraulic cylinder. 5. The apparatus according to claim 1, further comprising a contact / separation device for separating the opposite ends of the pair of long-side molds by utilizing its elastic deformation when moving each of the short-side molds. Variable width mold device. 6. The variable width mold apparatus according to claim 5, wherein the contact / separation device is any one of a link mechanism, a cam mechanism, a reverse screw feed mechanism, a pantograph mechanism, and a hydraulic cylinder.