JP2611154B2 - Molding method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding apparatus for heating and press-forming a work, such as a synthetic resin strip, mainly. The present invention relates to a technique for performing mold clamping at a high pressure while reducing the size of the apparatus.

[0002]

2. Description of the Related Art In heating and press-forming a work such as a strip of synthetic resin which is heated, the upper and lower dies are quickly matched to avoid a decrease in the heating temperature of the work. Good molding can be performed by strengthening the mold clamping. Therefore, conventionally, the mold plate to which the upper and lower molds are mounted has a ball screw shaft penetrated in four sides thereof, and a nut body is screwed to the ball screw shaft on the mold plate side,
Then, these four ball screw shafts are tuned and driven by an electric motor via a chain or a belt, and the ball screw shafts are rotated at a high speed to quickly move the upper and lower dies to perform mold matching. Is what it is.

By the way, the ball screw shaft has a low frictional resistance, rotates at a high speed, and it is easy to control the number of rotations to perform the mold matching and mold opening operations. (Sheet) material can be formed at a relatively low pressure as compared with press forming, and this type of forming apparatus is widely used. However, in recent years, in the heating and press forming of a foam sheet having a relatively thick work piece of, for example, about 3 mm, the upper and lower dies are clamped to obtain a deep-drawn product such as a bowl shape or a large beer cup. It is necessary to increase the applied pressure to about 20 tons. If an electric motor that drives the ball screw shaft at a high speed is used to obtain such a high applied pressure, a large, high-torque electric motor is required. In addition to the necessity, there is a problem that the whole apparatus becomes extremely large.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an object of the present invention is to perform high-speed mold matching of an upper and lower mold and to perform clamping of the mold with an apparatus. An object of the present invention is to provide a molding method and a molding apparatus capable of performing high-pressure while reducing the size.

[0005]

According to a first aspect of the present invention, there is provided a molding method for press-molding a plate-shaped workpiece w carried between upper and lower dies 1 and 2, wherein at least one of the upper and lower dies 1 and 2 is formed. Is moved at a high speed by an electric motor 6 using a ball screw mechanism having a ball screw shaft 3 and a nut body 4 screwed to the shaft screw 3 to form the upper and lower dies 1 and 2, and then the nut of the ball screw mechanism The mold is clamped by clamping the body 4 and rotating the nut body 4 by linear driving by the cylinder 5.

According to a second aspect of the present invention, there is provided a forming apparatus for press-forming a plate-shaped workpiece w carried between the upper and lower dies 1 and 2, wherein at least one of the upper and lower dies 1 and 2 is ball-formed by an electric motor 6. High-speed moving means 7 for moving at a high speed using a ball screw mechanism having a screw shaft 3 and a nut body 4 screwed thereto, a clamp device 8 for clamping the nut body 4 of the ball screw mechanism, and a clamp device A mold clamping means 9 for clamping the mold by rotating the nut body 4 clamped by the cylinder 8 by linear driving of the cylinder 5 is provided.

According to a third aspect of the present invention, one ball screw shaft 3 is attached to the center of the movable plate 10 on which the movable mold 1 is mounted. Claim 4
, The work w is a band plate made of synthetic resin, and includes a heater device 11 for heating the work w. The heater device 11 changes its position in the feed direction of the work w and
2 so as to be freely accessible.

[0008]

According to the first aspect of the present invention, the mold 1 is formed by a ball screw function having a ball screw shaft 3 and a nut body 4 screwed thereto.
Move at high speed. For example, in order to press-mold a heated synthetic resin strip work w, the upper and lower dies 1 and 2 can be quickly matched to avoid a decrease in the heating temperature of the work w. After the mold matching, the nut body 4 is rotated by the linear movement of the cylinder 5, and the mold can be strongly clamped by utilizing the high output of the cylinder 5. In the mold clamping by the cylinder 5, it is needless to say that the mold clamping pressure by the cylinder 5 can be made a predetermined pressure by, for example, setting the air pressure to be sent to the cylinder 5 to a predetermined pressure. Even if it deviates from the position, if it is within the range of the stroke of the cylinder 5, the positional deviation of the fixed mold 2 is absorbed, and it is not necessary to perform the positioning of the upper and lower dies 1 and 2 at the predetermined positions. The apparatus can be simplified while molding can be performed.

That is, the mold 1 is moved at a high speed by the ball screw mechanism to reduce the time for mold alignment and mold opening, and the cylinder 5 is used to perform high-pressure mold clamping to perform good molding. The feature is that the apparatus can be miniaturized. According to the second aspect, the same operation as the first aspect can be obtained. According to claim 3, the mold 1 to be moved receives a driving force at its center, and can apply a pressing force at its center even if the mold 1 is tilted, so that the apparatus can be driven by one ball screw shaft 3. Can be simplified, and good pressing can always be performed.

[0010] In claim 4, the upper and lower molds 1 to be used.
If the size of the workpiece w in the feed direction is changed, the heater device 11 is moved to approach the upper and lower dies 1 and 2 in response to the change in the size. A decrease in temperature can be avoided, and a good heating state can be obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. 1 shows a side view of the entire apparatus, FIG. 2 shows a side view without a protective cover, and FIG. 3 shows a plan view. In such an apparatus, a work w of a synthetic resin strip is conveyed by a conveying device 14 while sandwiching both sides in the width direction thereof, and is heated to a predetermined temperature by a heater device 11, and the heated work w is heated. It is carried into the molding device 15,
The work w heated in the forming device 15 can be formed under pressure. The work w is a sheet material of a general-purpose resin such as polyethylene, polystyrene and polypropylene, or a sheet material of a foamed resin such as styrene foam, and these are sequentially supplied from a supply unit (not shown). Hereinafter, the configuration of each of the above devices will be described in detail.

FIG. 4 shows the molding apparatus 15 and the base 1.
9 are provided with four columns 16 at the four corners.
An upper frame 20 is connected to the upper end of the frame to assemble a frame. The lower moving plate 17 is supported on the base 19 via the elevation drive means 21 shown in FIG.
The upper moving plate 10 is supported by means of lifting and lowering and mold clamping means 22 shown in FIG. 1, and the four corners of these upper and lower moving plates 10 and 17 are held by guide columns 16 via guide means 18 so as to be able to move up and down. ing. The lower mold 2 is removably mounted on the upper surface of the lower moving plate 17, and the upper die 1 is removably mounted on the lower surface of the upper moving plate 10. The work w is carried between the dies 1 and 2 by the transfer device 14, the upper and lower dies 1 and 2 are brought close to each other, and the upper and lower dies 1 and 2 are combined. Pressure molding can be performed between the two.

FIG. 5 shows the lifting and lowering means of the upper mold 1 and the mold clamping means 22. At the center of the upper moving plate 10, the ball screw shaft 3 is provided upright so as not to rotate. And ball screw shaft 3
The cylindrical body 23 is integrated with the nut body 4 which is screwed into the nut via a ball (not shown).
4 are attached. The cylindrical body 23 is rotatably held only via a bearing 28 by a fixed cylindrical body 29 fixed to the upper base 20. The electric motor 6 is mounted on the upper frame 20, and the output shaft 2 of the electric motor 6 is
5, a timing belt 27 is wound around a sprocket 26 fixed to the pulley 24 and a pulley 24 on the side of the cylindrical body 23, and the forward and reverse rotation of the electric motor 6 causes the nut body 4 to rotate forward and reverse through the cylindrical body 23, The upper movable plate 10 can be driven to move up and down via a ball screw shaft 3 screwed to 4. As described above, in the ball screw mechanism including the ball screw shaft 3 and the nut body 4 screwed thereto, high-speed rotation and control thereof are easy, and the configuration is collectively referred to as high-speed moving means 7.

A tightening disk 30 is provided around the outer periphery of the cylindrical body 23.
Is installed. A fastening body 36 is fitted on the outer periphery of the fixed cylindrical body 29 via a bearing 35 so as to be relatively rotatable. A pneumatically driven brake pad 31 is attached to the tightening body 36. The fastener 32 is attached to the fastening body 36 and protrudes. Chains 33 are fastened to both sides of the fastening tool 32.
The chains 33 are wound around a tightening body 36, and the ends thereof are engaged with the cylinder 5 driven by air pressure (see FIG. 6).

The lower drive plate 17 is similarly driven up and down as shown in FIG. That is, the ball screw shaft 3 hangs non-rotatably at the center of the lower moving plate 17. Then, a cylindrical body 23 is integrated with the nut body 4 screwed to the ball screw shaft 3 via a ball (not shown), and a pulley 24a is attached to the cylindrical body 23. The cylindrical body 23 is a fixed cylindrical body 2 fixed to the base 19.
9 is rotatably held only via a bearing 28. The timing belt 2 is attached to the pulley 24a.
7a is wound, and the electric motor 6a is
Can be driven in synchronization with the moving plate 10 on the upper mold 1 side. Also on the lower moving plate 17 side, a tightening disk 30 is mounted on the outer periphery of the cylindrical body 23, and a brake pad 31 driven by pneumatic drive is mounted on the outer circumference of the fixed cylindrical body 29.

The upper and lower brake pads 31, 3
In a state where 1 is released, the electric motor 6 is driven,
After the upper moving plate 10 is lowered, the lower moving plate 17 is raised, and the upper and lower dies 1 and 2 are matched, each brake pad 31 is tightened, and the tightening disk 30 is tightened and held. In this case, the nut body 4 is integrated with the lower fixed cylindrical body 29, and by locking the nut body 4 in this manner, the rotation of the lower ball screw shaft 3 is prevented, and the position of the lower mold 2 is firmly fixed. Fixed to. Meanwhile, on the upper mold 1 side, the brake pad 31 and the tightening disc 30 are integrated, and the nut body 4 is integrated with the tightening body 36. However, the fastening body 36 and the nut body 4 can be rotated by the bearings 28 and 35 on the fixed cylindrical body 29. Then, one of the cylinders 5 is contracted and the other cylinder 5 is opened to be freely extended. Thus, the upper mold 1 is securely clamped to the lower mold 2. In the example, about 20
Tons of mold clamping force can be obtained. In this case, the diameter of the ball screw shaft 3 is about 80 mm, the lead of the ball screw shaft 3 is about 20 mm, and the thrust of the cylinder 5 is 3 mm.
It is 34 kg, and the above-mentioned 20 tons of mold clamping force can be maintained throughout the 5 mm stroke of the cylinder 5. Then, the brake pad 31 and the tightening disc 3
Clamp conveyance 8 to clamp the nut body 4 at 0
Collectively. The configuration of such a clamp device 8 can be changed.

As described above, at least one of the upper and lower dies 1 and 2 is moved by the electric motor 6 at a high speed by using the ball screw mechanism having the ball screw shaft 3 and the nut body 4 screwed thereto. After the molds 1 and 2 are matched, the nut body 4 of the ball screw mechanism is clamped, and the nut body 4 is slightly rotated by linear driving by the cylinder 5 to perform mold clamping. The configuration for clamping the upper mold 1 in this manner is generally referred to as mold clamping means 9.

The mold 1 can be moved at a high speed by the ball screw function provided with the ball screw shaft 3 and the nut body 4 screwed to the shaft, for example, a work of a heated synthetic resin strip. In order to press-mold w, the upper and lower dies 1 and 2 are quickly matched to avoid a decrease in the heating temperature of the work w. Then, after the mold matching, the nut body 4 is slightly rotated by the linear motion of the cylinder 5, and the mold clamping is strongly performed by utilizing the high output of the cylinder 5.

By the way, the cylinder 5 is driven by pneumatic pressure, and the mold clamping pressure by the cylinder 5 can be set to a predetermined pressure by adjusting the air pressure to be fed to the cylinder 5 to a predetermined pressure by a relief valve or the like. Needless to say, even if the position of the fixed-side mold 2 is deviated from the predetermined position, it is within the range of the stroke of the cylinder 5.
Can be absorbed, there is no need to position the upper and lower dies 1 and 2 at a predetermined position, and the apparatus can be simplified while always performing good molding.

Moreover, the moving plate 1 for mounting the moving mold 1
0, a single ball screw shaft 3 is attached to the center, and the moved mold 1 receives a driving force (propulsive force) at the center, and even if the mold 1 is slightly inclined, it is pushed at the center. Pressure can be applied, and good molding is always performed while simplifying the apparatus with one ball screw shaft 3. In the figure, reference numeral 42 denotes a balancer, which uses a pneumatic cylinder similar to the cylinder 5 and applies a thrust substantially equal to the load on the moving plates 10 and 17 to maintain the horizontal balance of the moving plates 10 and 17.

A heater device 1 for heating the work w
Numeral 1 is configured so that the position can be changed in the feed direction of the work w on the lower rail 38 via the traveling runner 39. Such a position changing configuration of the heater device 11 can be variously changed in design. As described above, the heater device 11 includes the upper and lower dies 1, 2
When the size of the work w of the upper and lower dies 1 and 2 in the feed direction is changed, the heater device 11 is moved in response to the change in the size. The heater device 11 can be brought close to the upper and lower molds 1 and 2, and thus the heater device 11 is always brought close to the upper and lower molds 1 and 2 to avoid a decrease in the temperature of the work w.

As shown in FIG. 8, the heater device 11 includes heating plates 40, 40 on the upper and lower sides.
The work 40 is closed by the open / close cylinders 41, 41, the work w is sandwiched between the upper and lower hot plates 40, 40 with a space therebetween, and heated, and the work w is transferred by the transfer device 14 to the upper and lower dies 1, It can be brought between the two.

Although the present invention has been embodied in the molding apparatus 15 for molding a sheet-like work w made of synthetic resin, the present invention may be embodied in a press molding apparatus.

[0024]

According to the first aspect of the present invention, there is provided a molding method for press-molding a plate-like body carried between upper and lower dies,
At least one of the upper and lower molds is moved at a high speed using a ball screw mechanism having a ball screw shaft and a nut body screwed to the ball screw shaft by an electric motor, and the upper and lower molds are mold-matched. The mold is clamped by rotating the nut body with a linear drive by a cylinder, and the mold can be moved at high speed by the ball screw function with the ball screw shaft and the nut body screwed to it. For example, when press-molding a heated synthetic resin strip work, the upper and lower dies can be quickly aligned to avoid a decrease in the heating temperature of the work, and after the alignment, The advantage of this is that the nut can be slightly rotated by the linear motion of the cylinder and mold clamping can be performed strongly using the high output of the cylinder, and good molding can be performed. There is. Moreover, since the mold is clamped by the cylinder, it is needless to say that the mold clamping pressure by the cylinder can be set to a predetermined pressure by, for example, setting the air pressure to be sent to the cylinder to a predetermined pressure. Even if it is more displaced, if it is within the range of the stroke of the cylinder, the displacement of the fixed side mold can be absorbed, and it is not necessary to perform positioning at the predetermined position of the upper and lower molds, while always performing good molding This has the advantage that the device can be simplified.

That is, while the mold is moved at a high speed by the ball screw mechanism, the time for mold alignment and mold opening can be shortened, the mold is clamped at a high pressure by the cylinder, and good molding is performed. The invention is found in terms of downsizing. Claim 2 is a molding apparatus for press-molding a plate-shaped workpiece carried between the upper and lower molds, wherein at least one of the upper and lower molds is formed by an electric motor with a ball screw shaft and a nut body screwed to the ball screw shaft. High-speed moving means for moving at high speed using a ball screw mechanism provided,
A clamping device for clamping the nut body of the ball screw mechanism; and mold clamping means for clamping the mold by rotating the nut body clamped by the clamping device by linear driving by a cylinder. A similar effect can be obtained.

According to the third aspect of the present invention, since one ball screw shaft is attached to the center of the moving plate on which the moving mold is mounted, the moving mold receives a driving force at the center, and even if the mold is slightly moved. Even if it is tilted, it can apply a pressing force at its center and can simplify the device with one ball screw shaft, but can always perform good pressing and stabilize molding. There are advantages.

According to a fourth aspect of the present invention, the work is a band plate made of synthetic resin, and is provided with a heater device for heating the work. Therefore, when the size of the upper and lower mold workpieces in the feeding direction is changed, the heater device can be moved as close as possible to the upper and lower molds by moving the heater device in response to the change in the size, A change in the size of the upper and lower dies, that is, a change in the size of the molded product, can be performed to bring the heater device close to the upper and lower dies, thereby avoiding a decrease in the heating temperature of the workpiece and performing good heat molding. There is an advantage.

[Brief description of the drawings]

FIG. 1 is a side view of one embodiment of the present invention.

FIG. 2 is a side view showing the same with a protective cover removed.

FIG. 3 is a plan view of the same.

FIG. 4 is a cutaway front view of the same.

FIG. 5 is a partial cross-sectional side view showing a driving unit of the movable plate in the above.

FIG. 6 is a plan view of the same.

FIG. 7 is a partial cross-sectional side view showing a drive unit of a lower moving plate of the above.

FIG. 8 is a partial side view of the same heater device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper die 2 Lower die 3 Ball screw shaft 4 Nut body 5 Cylinder 6 Electric motor 7 High-speed moving means 8 Clamping device 9 Mold clamping device 10 Moving plate 11 Heater device

Claims (4)

(57) [Claims] 1. A molding method for press-molding a plate-like body carried between upper and lower molds, wherein at least one of the upper and lower molds is provided with a ball screw shaft by an electric motor and a nut body screwed to the ball screw shaft. After moving the ball screw mechanism at high speed to match the upper and lower molds, clamp the nut body of the above ball screw mechanism and rotate the nut body by linear drive by a cylinder to perform mold clamping. Characteristic molding method. 2. A molding apparatus for press-molding a plate-shaped workpiece carried between upper and lower dies, comprising at least one of the upper and lower dies by means of an electric motor and a ball screw shaft and a nut member screwed thereto. High-speed moving means for moving the ball screw mechanism at high speed, a clamping device for clamping the nut body of the ball screw mechanism, and rotating the nut body clamped by the clamping device by linear driving by a cylinder. A molding apparatus comprising a mold clamping means for performing mold clamping. 3. The molding apparatus according to claim 2, wherein one ball screw shaft is attached to a center of a moving plate on which a moving die is mounted. 4. The work is a strip material made of synthetic resin, and is provided with a heater device for heating the work, and the heater device is configured to change its position in a work feed direction and to be freely accessible in an up-and-down direction. The molding apparatus according to claim 2 or 3, wherein