KR20240115411A - Injection molding machine for fabricating super-sized injection molded product - Google Patents

Abstract

The present invention relates to an injection molding machine for manufacturing ultra-large injection molded products.
The injection molding machine for manufacturing ultra-large injection molded products according to the present invention has a spray nozzle for double-sided molding and a spray nozzle for general molding. The spray nozzle for double-sided molding has a spray hole of a first diameter, and the spray nozzle for general molding has a spray hole of a second diameter, and the first diameter is larger than the second diameter.
According to the present invention, the injection molding machine can properly set the injection amount of molten resin per hour for both double-sided molding and general molding, thereby improving the yield of injection molded products.

Description

Injection molding machine for producing ultra-large injection molded products {INJECTION MOLDING MACHINE FOR FABRICATING SUPER-SIZED INJECTION MOLDED PRODUCT}

The present invention relates to injection molding machines, and in particular to technology capable of double-sided molding.

An injection molding machine is a device for injecting molten resin into the cavity of the product shape.

In general, injection molding machines are divided into mold clamping equipment and injection equipment.

The clamping device includes pairs of molds, and the gap between the molds can be widened or narrowed.

In most cases, a paired mold consists of a fixed mold and a moving mold.

When the movable mold comes into contact with the fixed mold and enters a mold-closed state, a cavity of the product shape is formed.

Conversely, when the movable mold is separated from the fixed mold and is in a mold-opening state, the cavity is opened and the injected product can be pulled out.

The injection device melts the particulate resin in the barrel and then injects the molten resin into the cavity through the injection nozzle.

The injection nozzle of the injection device may be in contact with the fixed mold or may be spaced apart from the fixed mold.

The injection device sprays molten resin while the mold is closed and the spray nozzle is in contact with the moving mold. Then, the resin sprayed from the injection device is injected through a runer (or resin furnace and runner) into a cavity formed by a fixed mold and a moving mold.

Meanwhile, there is an injection molding machine equipped with a stack mold in which molding is performed on both sides.

A stack mold is a special mold designed to produce twice as many injection molded products in one molding cycle.

The stack mold further includes an intermediate mold disposed between the fixed mold and the movable mold. The basic purpose of the stack mold is to use existing injection molding machines without increasing the projected area, but to double the production volume and reduce the cost by half.

The cavity where the injection molded product is formed is formed between the fixed mold and the intermediate mold, and between the intermediate mold and the moving mold.

The intermediate mold may be moved in part in conjunction with the movement of the movable mold that moves during the mold opening or mold closing process.

During mold closing, the mobile mold moves toward the fixed mold and pushes the intermediate mold, so that the mobile mold, intermediate mold, and fixed mold are connected.

Of course, at mold opening, the movable mold, the intermediate mold, and the intermediate mold and the fixed mold are spaced apart from each other.

For the movement of the intermediate mold required for mold opening and mold closing, devices with a Z-type link structure or rack and pinion structure are mainly used.

The present invention relates to an injection molding machine using a stack mold.

In order for stack molds to be applied, various limitations must be overcome.

For example, the weight deviation of both injection molded products, the special hot runer system that allows simultaneous filling of cavities on both sides, the stroke (travel distance) of the moving mold and intermediate mold, and the pressure loss due to the long and somewhat complicated resin movement path. Changes in the temperature of the resin, leakage of the resin due to double-sided injection, clogging problems caused by subsequent solidification, and simultaneous withdrawal of both injection molded products are limitations in the application of stack molds.

Due to the above limitations, existing stack molds have been applied only to the production of small injection molded products.

It has been extremely difficult to satisfy the above constraints for very large pallets that are more than 1m in length and width, so the application of stack molds has not been realized so far.

For example, an injection molding machine using a stack mold requires precise alignment between the fixed mold, intermediate mold, and moving mold during mold closing. Conversely, when opening a mold, the gap between the fixed mold and the intermediate mold and the intermediate mold and the moving mold also need to be set precisely.

However, in order to manufacture ultra-large injection molded products, the size of each mold increases accordingly, and the load on each mold and component also increases proportionally. This means that matching each mold is that difficult.

Also, if the molds are spaced too widely apart, the middle part of the tie bar will be hit by its own weight. Therefore, overload occurs during the subsequent movement of the moving mold, which causes damage to the equipment. And this reduces the precision of mold opening and mold closing in the future.

However, if the molds are spaced too narrowly apart, defects may occur during the extraction of the injection molded product.

In addition, injection molding machines using stack molds have cavities formed on both sides, so the amount of resin sprayed is large. Therefore, setting the injection amount of molten resin per hour is also very important.

If the injection time is lengthened to increase the injection amount or the injection time is too short by increasing the injection amount per second, defects may occur in the production of injection molded products that react sensitively to conditions such as the temperature of the molten resin, filling time, and injection pressure.

Meanwhile, there is a technology (hereinafter referred to as 'prior art') presented in Republic of Korea Patent No. 10-1146198 (title of invention: multi-sided injection device) related to an injection molding machine to which a stack mold is applied.

The injection device in the prior art sprays molten resin directly into the intermediate mold. Therefore, the mold clamping device (named 'shape member' in the prior art) and the injection device (named 'injection member' in the prior art) are combined in a 'ㅗ' shape.

Resin is divided into two directions in the middle mold and injected into cavities on both sides. And the product is molded simultaneously on both sides of the intermediate mold.

According to the prior art, both the first and second templates on both sides of the intermediate mold are movable. Therefore, it is easy to secure the gap between the first template and the intermediate mold and the gap between the intermediate mold and the second template.

However, according to the prior art, the injection nozzle of the injection device (named 'injection nozzle' in the prior art) is in contact with the intermediate mold, so there is the following problem.

First, the efficiency of spatial arrangement is reduced because the mold clamping device and the injection device are not arranged side by side, but in a 'ㅗ' shape.

Second, because the molds on both sides of the fixed intermediate mold must be moved, the movement configurations for moving the molds on both sides become complicated, and the structure for applying mold closing force to the molds also becomes complicated.

Third, since the intermediate mold is fixed and the injection nozzle of the injection device comes into contact with the intermediate mold, its versatility is low. For example, if the prior art is followed, it becomes difficult to convert it to a general injection molding machine by excluding the intermediate mold. Here, a general injection molding machine refers to one equipped with only a fixed mold and a moving mold.

For this reason, the prior art is insufficient as an injection molding machine preferred by actual customers.

Republic of Korea Patent Publication No. 10-2000-0000478 Republic of Korea Patent No. 10-1146198 Republic of Korea Patent No. 10-2458015

The present invention was created with the following motivation to enable the application of stack molds for producing ultra-large injection molded products.

First, it is necessary to properly set the injection amount of molten resin per hour to overcome the various limitations of double-sided injection (resin temperature, resin movement time, injection pressure, etc.).

Second, it is necessary to freely switch between double-sided injection and general injection while following the layout structure of a general injection molding equipment.

The injection molding machine for manufacturing ultra-large injection molded products according to the present invention includes a mold clamping device that forms a cavity with the shape of the injection molded product to mold the injection molded product or opens the cavity to allow the molded injection molded product to be withdrawn; an injection device disposed in line with the mold clamping device and filling the cavity with molten resin; and a base frame supporting the mold clamping device and the injection device; It includes: an injection nozzle for double-sided molding, the injection device having an injection hole of a first diameter through which molten resin is injected, and disposed in a side direction of the mold clamping device; a cylindrical barrel on which the spray nozzle for double-sided molding is detachably mounted and which has a transport hollow inside that functions as a passage through which the resin can be transported; A hopper coupled to the barrel and configured to supply particulate resin into the transport cavity; A screw disposed in the transfer hollow and having a transfer thread formed on its outer surface to transfer the resin toward the mold, and pressurizing the molten resin toward the mold so that the molten resin can be sprayed through the injection hole; an actuator that rotates the screw to transport the resin or moves the screw so that the molten resin is sprayed through the injection hole of the first diameter while being pressurized by the screw; a heater installed to contact the outer surface of the barrel and melting the resin in the transfer cavity; an advance/retractor that advances/retracts the barrel so that the injection nozzle is in contact with or spaced apart from a fixed mold in the clamping device; and a general molding spray nozzle that can be replaced with the double-sided molding spray nozzle and be detachably mounted on the barrel and has a spray hole of a second diameter through which molten resin is sprayed. It includes, and the first diameter and the second diameter are different from each other.

The first injection nozzle is for double-sided molding, the second injection nozzle is for general molding, and the first diameter is larger than the second diameter.

The first diameter is 16 mm and the second diameter is 8 mm or 12 mm.

The first diameter is within a range of 133.33% to 200.00% of the second diameter.

According to the present invention, switching between double-sided injection and general injection can be easily made, and the injection amount per hour of molten resin can be appropriately set in both double-sided injection and general injection, so the yield can be improved.

Figure 1 is a schematic diagram of an injection molding machine for manufacturing ultra-large injection molded products according to an embodiment of the present invention.
Figure 2 is an excerpt of a mold clamping device applied to the injection molding machine of Figure 1.
Figure 3 is a partial excerpt of the clamping device of Figure 2.
Figure 4 is an excerpt of an injection device applied to the injection molding machine of Figure 1.
Figure 5 is a conceptual reference diagram for explaining the movement path of resin.

Preferred embodiments according to the present invention will be described with reference to the accompanying drawings, but for brevity of explanation, descriptions of well-known configurations will be omitted or compressed as much as possible.

Figure 1 is a configuration diagram of an injection molding machine (IMM, hereinafter abbreviated as 'injection molding machine') for manufacturing large injection molded products according to an embodiment of the present invention.

An injection molding machine (IMM) includes a mold clamping device 100, an injection device 200, and a base frame (BP).

The mold clamping device 100 forms a cavity having the shape of an injection molded product to mold the injection molded product, or opens the cavity to allow the molded injection molded product to be taken out.

The injection device 200 is arranged in line with the mold clamping device 100 and fills the cavity formed by the mold clamping device 100 with molten resin.

The base frame (BP) supports the mold clamping device 100 and the injection device 200. According to this embodiment, the mold clamping device 100 on the left and the injection device 200 on the right are installed in a line on the base frame BP. Hereinafter, the features of the mold clamping device 100, the injection device 200, and the present invention will be described in detail by dividing them into a table of contents.

<A brief description of the clamping device>

FIG. 2 is a schematic diagram of the mold clamping device 100, and FIG. 3 is a partial perspective view of the mold clamping device 100.

As referenced in FIGS. 2 and 3, the clamping device 100 includes a fixed platen 111, a fixed mold 112, a movable platen 121, a movable mold 122, a mover 130, and four retainers. It includes (140), a fixture 150, an intermediate mold 161, a manifold 162, a support body 170, and a guider 180.

The fixed template 111 is disposed to face the injection device 200 and is fixedly installed to the base frame BP.

At the square corners of the fixing plate 111, insertion holes IH1 are formed into which the right side of the tie bar 141, which will be described later, is inserted.

The fixed mold 112 is fixedly coupled to the fixed template 111 so as to face the movable template 121.

The movable template 121 is disposed to face the fixed template 111 on the opposite side (left side in the drawing) of the fixed template 111.

The movable template 121 is provided to be able to move in a direction closer to or away from the fixed template 111 (left and right direction in the drawing). For this purpose, the movable template 121 is coupled to the base frame (BP) by providing a guide member that enables sliding movement, such as an LM guide (not shown).

Insertion holes (IH2) into which the left side of the tie bar 141 can be inserted are also formed in the square corners of the movable template 121. The four insertion holes (IH2) in the movable template 121 correspond to the four insertion holes (IH1) in the fixed template 111.

The movable mold 122 is fixedly coupled to the movable plate 121 so that it faces toward the fixed mold 111.

Since the movable mold 122 is fixed to the movable template 121, it moves in conjunction with the movement of the movable template 121.

The mover 130 moves the movable template 121 so that the movable template 121 approaches or moves away from the fixed template 111.

Four retainers 140 are provided to maintain mold closing force when injection is performed.

Each retainer 140 includes a tie bar 141 and a hydraulic cylinder 142.

The right side of the tie bar 141 passes through the insertion hole (IH1) of the fixed plate 111 and is coupled to the hydraulic cylinder 142, and the left side passes through the insertion hole (IH2) of the movable plate 121. there is.

On the left side of the tie bar 141, male threads are formed for binding to the moving template 121.

The hydraulic cylinder 142 pulls or releases the tie bar 141 using hydraulic pressure.

The hydraulic cylinder 142 is coupled to the fixed template 111.

The fixture 150 fixes and binds the movable plate 121 to the tie bar 141 or releases the binding.

When the movable plate 121 is bound to the tie bar 141 by the fixer 150, when the hydraulic cylinder 142 pulls the tie bar 141, the movable plate 121 is also pulled by the hydraulic cylinder 142. It's pulled. So the mold-closing force can be maintained.

On the other hand, when the fixer 150 releases the binding between the movable plate 121 and the tie bar 141, the movable plate 121 becomes movable by the movable plate 130.

The fixture 150 includes four half nuts 151 and a binding circle 152.

The half nut 151 has a female thread that can be screwed to the male thread of the tie bar 141. Therefore, the half nut 151 can be screwed to the tie bar 141 or the screw coupling can be released.

The half nut 151 is coupled to the moving template 121. Therefore, when the half nut 151 and the tie bar 141 are screwed together, the moving template 121 and the tie bar 141 are coupled. And when the screw connection between the half nut 151 and the tie bar 141 is released, the binding between the movable plate 121 and the tie bar 141 is released.

The binding member 152 operates the half nut 151 so that the half nut 151 and the tie bar 141 are screwed together, or the screw coupling between the half nut 151 and the tie bar 141 is released.

The intermediate mold 161 is disposed between the fixed mold 112 and the movable mold 122.

In the injection molding machine (IMM) according to the present invention, cavities are formed between the fixed mold 112 and the intermediate mold 161, and between the moving mold 122 and the intermediate mold 161, and two cavities are formed in one injection cycle. Very large injection molded parts (e.g. very large pallets) are produced.

The middle mold 161 is provided to be movable in the left and right directions. The movement of the intermediate mold 161 is performed by receiving the driving force of the movable template 121 through a guide pin that interconnects the intermediate mold 161 and the fixed mold 112 or the movable mold 122, or by the movable mold 121. This can be achieved by a device with a mounted Z-link structure or a rack and pinion structure.

The manifold 162 is mounted on the intermediate mold 161 and provides a hot runner for the resin moving within the intermediate mold 161.

A runner through which molten resin moves is formed on the metal manifold 162, and a heater is embedded around the runner. Therefore, the molten resin moving through the manifold 162 can be filled into the cavity while maintaining the heated temperature. For this reason, the runner provided by the manifold 162 is called a hot runner.

The support body 170 supports the intermediate mold 161 so that the intermediate mold 161 is disposed between the fixed mold 112 and the movable mold 122. The lower end of the intermediate mold 161 is firmly coupled to the upper end of the support body 170.

The support 170 is provided to be movable in the left and right directions. Therefore, when the intermediate mold 161 moves left and right, the support body 170 also moves left and right.

The guider 180 is fixedly installed on the base frame BP and guides the left and right movement of the support body 170. That is, the upper region of the support 170 is coupled to the intermediate mold 161, and the lower region of the support 170 is coupled to the guider 180.

As a result, the guider 180 guides the left and right movement of the intermediate mold 160 by placing the support body 170.

The guider 180 may be provided with a pair of LM rails that are long in the left and right directions and symmetrical in the front and rear directions, and LM blocks that are rail-connected to the pair of LM rails.

The guider 180 must have rigidity and durability to withstand the load of the intermediate mold 161 and the support body 170.

The injection molding machine (IMM) according to the present invention is for double-sided injection of injection molded products such as ultra-large pallets. In this case, the weight of the intermediate mold 161 and the support body 170 reaches tens of tons. Therefore, the guider 180 needs to have a structure and durability that can withstand a load of tens of tons.

Additionally, the guider 180 needs to be provided to lower the height of the support 170 as much as possible.

When the height of the support body 170 is high, the height of the intermediate mold 161 is high, so the height of the fixed mold 112 and the movable mold 122 also increases, which increases the overall height and size of the equipment.

Furthermore, the injection molding machine (IMM) according to the present invention has a structure that can be used interchangeably for general molding and double-sided molding. Therefore, if it is used for double-sided molding and needs to be converted to general molding, the intermediate mold 161 and support 170 must be separated from the injection molding machine (IMM). In addition, if it is used for general molding and needs to be converted to double-sided molding, the intermediate mold 161 and support 170 must be installed in the injection molding machine (IMM). In these processes, the work of separating or installing the intermediate mold 161 and the support body 170, which have very large loads, involves a lot of effort and risk. Therefore, it is necessary to reduce effort and risk as much as possible, and this can be partially realized by lowering the height of the support body 170. This will be explained in more detail later.

In order to lower the height of the support body 170 as described above, it may be more desirable to install a large number of guiders 180 with a small load-bearing capacity rather than a small number of guiders 180 with a large load-bearing capacity. This will be explained using an LM guide equipped with an LM rail and LM block as the guider 180 as an example.

If a small number of large LM rails are applied, the size of the LM block that must withstand the load increases, and the top and bottom thickness of the LM block itself becomes thicker. And this point acts as a limit to further lowering the height of the support body 170. On the other hand, if the size of the LM block is reduced by applying multiple small LM rails, the top and bottom thickness of the LM block itself becomes smaller, allowing the height of the support to be lowered accordingly.

Also, instead of applying small LM blocks, the number of LM blocks needs to be increased to withstand the load. However, as the number of LM blocks increases, the number of support points for the support body 170 increases, which means that the guider 180 can perform the support and guidance function for the intermediate mold 161 and the support body 170 with greater stability. It also means that

Next, the operation of the above clamping device 100 will be described.

When injection is to be performed, the mover 130 moves the movable platen 121 toward the fixed platen 111 (to the right in the drawing).

As the mobile template 121 moves, the mobile mold 122 also moves to the right and first contacts the intermediate mold 161. And the moving mold 122 and the intermediate mold 161 move together toward the fixed mold 112. When the right side of the intermediate mold 161 comes into contact with the left side of the fixed mold 112 and the movement of the movable template 121 is completed, the binding circle 152 operates to connect the half nut 151 and the tie bar 141. is screwed together, and thereby the movable template 121 and the tie bar 141 are coupled. Then, the hydraulic cylinder 142 pulls the tie bar 141 to the right to maintain the mold closing force. In this state, the mold closing force is maintained and the molten resin is injected by the injection device 100.

After injection is completed and the injection molded product is solidified, the screw coupling between the half nut 151 and the tie bar 141 is released by the binding member 152. Then, the mover 130 moves the movable template 121 in the direction opposite to the fixed template 111 (to the left in the drawing). At this time, the mobile mold 122 is first moved to the left together with the mobile template 121, and when the distance between the mobile mold 122 and the intermediate mold 161 is widened by a set distance, the intermediate mold (161) is moved by the guide pin. 161) and the support body 170 are dragged along the movement of the movable mold 122 and move in the left direction, and the space between the fixed mold 112 and the intermediate mold 161 widens.

Alternatively, depending on the implementation, the movable mold 122, the intermediate mold 161, and the support 170 along with the movable template 121 move to the left, and the space between the fixed mold 112 and the intermediate mold 161 is moved to the left. When the gap is expanded by a set distance, only the mobile mold 122 along with the mobile template 121 may be implemented to move further to the left.

For reference, a separate stopper needs to be provided to prevent the middle mold 161 from moving excessively to the left. However, if the guider 180 is equipped with an LM rail and an LM block, the left end of the LM rail may be implemented to function as a stopper.

If a stopper is provided to prevent the middle mold 161 from moving excessively to the left, it may be desirable to implement it so that the manager can set the stopping position of the middle mold 161. In this case, even if the injection molded product changes due to replacement of the mold, the gap between the fixed mold 111, the moving mold 121, and the intermediate mold 161 can be secured to match the replaced mold.

In one plate, the space between the movable mold 122 and the intermediate mold 161 and between the intermediate mold 161 and the fixed mold 112 is widened by a set distance, and the fixed mold 112 and the fixed mold 112 are separated by a withdrawal robot (not shown). The injection molded product between the intermediate mold 161 and the injection molded product between the moving mold 122 and the intermediate mold 161 are pulled out.

<A brief description of the injection device>

Figure 4 is a schematic diagram of the injection device 200.

The injection device 200 injects the molten resin into the cavity of the mold. For this purpose, the injection device 200 includes an injection nozzle 210, a barrel 220, a hopper 230, a screw 240, an actuator 250, a heater 260, and an advance/retractor 270.

The spray nozzle 210 has a spray hole (SH) through which the molten resin inside the barrel 220 is sprayed, and is disposed toward the clamping device 100 (left side in the drawing).

The injection nozzle 210 is detachably mounted on the left end of the barrel 220.

The left end of the barrel 220, in the direction in which the fixed mold 112 is located, is coupled to the injection nozzle 210.

The barrel 220 is provided in a cylindrical shape with a transfer hollow (TC) inside that functions as a passage through which resin can be transferred.

An inlet hole (TH) is formed on the right side of the barrel 220 through which the particulate resin supplied from the hopper 230 is injected into the transfer hollow (TC).

The hopper 230 is coupled to the barrel 220 to supply particulate resin to the transfer hollow (TC). That is, the particulate resin poured into the hopper 230 is input into the transfer hollow (TC) of the barrel 220 through the input hole (TH).

The screw 240 is disposed in the transfer hollow (TC) of the barrel 220.

A transfer thread (TS) is formed on the outer surface of the screw 240, so that when rotated by the actuator 250, the resin is transferred to the left side toward the mold.

The screw 240 may be advanced to the left or retracted to the right by the actuator 250. When the screw 240 moves forward, the molten resin accumulated on the left side of the barrel 220 is pressurized and sprayed through the spray nozzle 210. And the molten resin injected through the injection nozzle 210 fills the cavity of the mold.

The actuator 250 is disposed in the opposite direction to the spray nozzle 210.

The actuator 250 moves the resin in the transfer cavity (TC) to the left or operates the screw 240 to pressurize the molten resin and spray it toward the mold.

The actuator 250 has a rotation source 251 and a pressure source 252.

The rotation circle 251 rotates the screw 240 so that the resin in the transfer hollow (TC) can be transferred to the left by the action of the transfer screw (TS).

The pressure source 252 moves the screw 240 to the left so that the molten resin can be sprayed through the injection hole (SH) while being pressurized by the screw 240, and then retracts the screw 240 to the right. Have them prepare for the next injection.

The heater 260 is installed to contact the outer surface of the barrel 220.

The heat generated by the heater 260 is conducted to the barrel 220 and then transferred to the resin in the transfer cavity (TC) to melt the particulate resin, and the already melted resin is maintained in a molten state.

For reference, the particulate resin is melted not only by the heat generated by the heater 260, but also by the heat (shear heat) generated during the transfer process by the screw 240.

The advance/retractor 270 advances and retreats the barrel 220 in the left and right directions so that the injection nozzle 210 is in contact with or spaced apart from the fixed mold 112. Therefore, when the advance/retractor 270 operates, the injection nozzle 210, barrel 220, hopper 230, screw 240, actuator 250, and heater 260 all advance and retract in the left and right directions together.

When the injection nozzle 210 comes into contact with the fixed mold 112 by the advance/retractor 270, the injection hole SH communicates with the resin path in the fixed mold 112, thereby enabling injection. In addition, the injection nozzle 210 may be spaced apart from the fixed mold 112 by the advance/retractor 270.

Next, the operation of the injection device 200 having the above configuration will be described.

First, in a state in which the injection nozzle 210 is spaced apart from the fixed mold 112 by the advance/retractor 270, the advance/retractor 270 operates to advance the barrel 220 to the left, and the injection nozzle 210 It comes into contact with the fixed mold 112, and the injection hole SH of the injection nozzle 210 communicates with the resin path in the fixed mold 112, making injection possible.

The particulate resin poured into the hopper 230 is input into the transfer hollow (TC). The particulate resin introduced into the transfer hollow (TC) moves to the left as the screw 240 rotates by the rotation circle 251 and is melted by shear heat and heater heat. At the same time, the screw 240 moves backwards to the right by the pressure source 252 and measures the molten resin.

The molten resin accumulates in the left area of the screw 240 in a measured amount required for injection.

Afterwards, when the pressure source 252 moves the screw 240 forward in the left direction, the molten resin is sprayed while being pressurized. And the molten resin injected through the injection hole (SH) of the injection nozzle 210 is input into the cavity through the resin of the fixed mold 112 and the hot runner provided by the manifold 162.

When the cavity is filled and the injection of resin is completed, the screw 240 rotates again to melt the resin, and at the same time, the screw 240 moves backwards to the right and returns to the state of preparing for the next injection while measuring the melted resin. Goes.

Meanwhile, when replacing the type of resin supplied to the injection device 200 or stopping the repetition of the injection cycle, such as for maintenance of the injection device 200, use the advance/retractor 270 to move the barrel 220 to the right. By retreating, the injection nozzle 210 can be spaced apart from the fixed mold 112.

Meanwhile, the injection molding machine (IMM) according to the present invention can switch between general molding and double-sided molding. Particularly important features of the present invention will be described accordingly.

<Description of features of the invention>

1. Matters regarding the spray nozzle

The injection molding machine (IMM) according to the present invention is intended to produce ultra-large injection molded products with a width and length of approximately 1 m or more, and is especially capable of double-sided molding. Therefore, the injection molding machine (IMM) is equipped with a spray nozzle 210 having a spray hole (SH) with a diameter of 16 mm.

However, when the intermediate mold 161 is removed and converted to general injection use, the injection nozzle 210 needs to be replaced.

In general, the injection pressure of the molten resin, injection time (resin movement time), and temperature changes of the resin during the filling process are factors that have an important impact on the quality of injection molded products. If the spraying is too slow or too fast, defects may occur in the production of injection molded products.

The diameter of the injection hole (SH) in the injection nozzle 210 is closely related to the injection pressure, injection time, and temperature change during movement.

In the case of double-sided molding, the cavity volume is approximately twice that of general molding. Therefore, the spray nozzle 210 for double-sided molding needs to have a spray hole (SH) with a larger diameter than the spray hole (SH) of the spray nozzle 210 for general molding. Only then can the optimal injection pressure and injection time be set, and temperature changes in the resin during the filling process can be properly considered.

In that respect, when using the injection molding machine (IMM) according to the present invention for general molding, it is necessary to reduce the injection hole (SH) of the injection nozzle 210. According to a preferred example of the present invention, the spray hole (SH) of the spray nozzle 210 applied for general molding has a diameter of 8 mm or 12 mm.

In other words, the diameter of the spray hole (SH) in the spray nozzle 210 used for double-sided molding is twice or 4/4 times the diameter of the spray hole (SH) in the spray nozzle 210 used for general molding. Set it to be enlarged by 3 times.

Therefore, the spray nozzle 210 with a spray hole (SH) with a diameter of 8 mm or 12 mm for general molding must be replaced with a spray nozzle 210 with a spray hole (SH) with a diameter of 16 mm for double-sided molding. . This means that the spray hole (SH) of the spray nozzle 210 for double-sided molding is expanded by approximately 133.33% or 200.00% compared to the spray hole (SH) of the spray nozzle 210 for general molding.

Of course, the diameter of the injection hole (SH) may need to change due to changes in the current outdoor temperature, resin temperature during the filling process, travel distance, injection pressure, injection time, etc. However, since the injection nozzle 210 cannot be replaced one by one for all changes in conditions, the injection hole (210) has a diameter within the range of 133.33% to 200.00% of the diameter of the injection hole (SH) of the general molding injection nozzle 210. It may be more desirable to install it with a spray nozzle 210 for double-sided molding (SH) and adjust other variables accordingly.

As such, the injection molding machine (IMM) according to the present invention is provided with a spray nozzle 210 for general molding and a spray nozzle 210 for double-sided molding as one set in order to switch between general molding and double-sided molding. It can be implemented as much as possible.

That is, the injection molding machine (IMM) according to the present invention is basically provided with a spray nozzle 210 for double-sided molding having a spray hole (SH) with a diameter of 16 mm mounted on the barrel 220, and a spray nozzle 210 with a diameter of 8 mm and/or A general molding spray nozzle 210 with a 12 mm diameter spray hole (SH) is provided for replacement. Of course, the spray nozzle 210 for general molding may be mounted on the barrel 220 and the spray nozzle 210 for double-sided molding may be provided separately.

In conclusion, the injection molding machine (IMM) according to the present invention provides two injection nozzles 210, and an injection hole (SH) provided separately from the injection hole (SH) of the injection nozzle 210 currently mounted on the barrel 220. The diameters of the nozzles 210 must be different.

2. Matters regarding support

The support body 170 supports the intermediate mold 161 in double-sided molding, but is an unnecessary component in general molding in which the intermediate mold 161 is excluded.

Therefore, when the injection molding machine (IMM) according to the present invention is converted to general molding, it is necessary to remove the intermediate mold 161 and the support body 170.

The intermediate mold 161, which is generally used to manufacture ultra-large injection molded products, weighs tens of tons. The load of the support body 170, which must support the intermediate mold 161 while withstanding the load of the intermediate mold 161, is also significant.

Therefore, mounting, disassembling, and withdrawing the support body 170 requires a great deal of effort. To solve this problem, the injection molding machine (IMM) according to the present invention has a special configuration.

In the injection molding machine (IMM) according to the present invention, the height of the top of the support 170 is set to be lower than the bottom of the fixed mold 112 and the moving mold 122. Then, the injection molding machine (IMM) can be converted from double-sided molding to general molding by only removing the intermediate mold 161. That is, the injection molding machine (IMM) according to the present invention does not need to have the task of dismantling or installing the support body 170 regardless of switching between general injection and double-sided injection.

Of course, the bottom height of the intermediate mold 161 should also be lower than the bottom height of the fixed mold 112 and the movable mold 122. Therefore, as mentioned above, it is desirable to reduce the height of the guider 180 as much as possible.

To explain the above point more conceptually and comprehensively, even when the injection molding machine (IMM) is used for general molding, the installed support 170 is prevented from interfering with the fixed mold 112 and the moving mold 122. This means you need to have structure.

3. Matters regarding the distance between the mobile template and the fixed template

With the gap between the fixed template 111 and the movable template 121 widened to the maximum, the distance between the fixed template 111 and the movable template 121 (hereinafter referred to as 'maximum distance') is longer in double-sided molding compared to general molding. It needs to be set longer.

However, if the distance between the fixed template 111 and the movable template 121 is too long, a problem may occur in which the tie bar 141 sags due to the load. However, if the distance between the fixed template 111 and the movable template 121 is too short, it becomes difficult to extract the injection molded product from both sides of the intermediate mold 161.

Meanwhile, the injection molding machine (IMM) according to the present invention is for manufacturing pallets, which are very large injection molded products.

When placed on the ground, a pallet is approximately 1m long and horizontal, and its height is about 120mm.

Therefore, according to the present invention, considering the height of the pallet of 120 mm, the distance between the fixed template 111 and the movable template 121 for double-sided molding is greater than the distance between the fixed template 111 and the movable template 121 for general injection. It is secured to be as long as 400mm. Here, the height of the pallet becomes the left and right width of the pallet at the time it is pulled out after molding. That is, according to a preferred example of the present invention, when the left and right widths of the pallet that are to be injection molded and extracted from the injection molding machine (IMM) are 120 mm, the maximum distance between the fixed platen 111 and the moving platen 121 in double-sided injection is that of general injection. It is necessary to extend 400 mm more than the maximum distance between the fixed template 111 and the movable template 121. In other words, this means that when switching from general injection to double-sided injection, the maximum distance between the fixed platen 111 and the moving platen 121 must be secured by approximately 333.33% of the left and right widths of the injection molded product to be drawn out. .

Of course, the maximum distance between the fixed template 111 and the mobile template 121 may be flexible depending on the structure and operation precision of the extraction robot, the rigidity of the tie bar 141, etc. However, for double-sided molding, the maximum distance between the fixed platen 111 and the movable platen 121 is secured within a range of approximately 290.00% to 375.00% of the left and right widths of the injection molded product to be drawn compared to the maximum distance for general molding. It may be considered desirable.

4. Matters regarding runners

Generally, runners in injection molding machines (IMM) are divided into hot runners and cold runners.

To implement a hot runner, a manifold 162 is required to apply heat to the molten resin just before it moves to the cavity.

In an injection molding machine (IMM) for double-sided molding, it is desirable to have a structure in which molten resin is simultaneously input into both cavities through the intermediate mold 161 by mounting the manifold 162 on the intermediate mold 161.

Therefore, in the injection molding machine (IMM) according to the present invention, the manifold 162 is mounted on the intermediate mold 161 as shown in the conceptual reference diagram of FIG. 5. Accordingly, a resin passage (RW) through which molten resin can move to the hot runner (HR) in the manifold 162 is formed in the fixed mold 112.

One end of the resin furnace (RW) communicates with the injection hole (SH) of the injection nozzle 210, and the other end communicates with the hot runner (HR). Therefore, the molten resin injected from the injection nozzle 210 of the injection device 200 flows to the hot runner (HR) disposed on the intermediate mold 161 along the resin furnace (RW) disposed on the fixed mold 112. After moving, it is divided into two cavities (C1, C2) and filled.

For reference, the resin furnace (RW) may be provided by a separate heating nozzle (HN) provided in the fixed mold 112 to maintain the temperature even while the molten resin moves through the resin furnace (RW). .

The above-described embodiments are only described as preferred examples of the present invention, and may have various application forms. Therefore, the present invention should not be understood as limited to the content described above. Instead, the scope of rights of the present invention should be understood as the separately stated claims and their equivalents.

IMM: Injection molding machine for producing ultra-large injection molded products
100: clamping device
C1, C2: Cavity
200: Injection device
210: spray nozzle
SH: spray hole
220: barrel
TC: Transfer hollow
230: Hopper
240: screw
TS: Feed thread
250: actuator
260: heater
270: Advance and retreat
BP: Base frame

Claims (4)

A mold clamping device 100 that forms cavities (C1, C2) having the shape of an injection molded product to mold the injection molded product, or opens the cavity (C1, C2) to allow the molded injection molded product to be extracted;
An injection device 200 arranged in line with the mold clamping device 100 and filling the cavities C1 and C2 with molten resin; and
A base frame (BP) supporting the mold clamping device 100 and the injection device 200; Including,
The injection device 200 is
a first spray nozzle 210 having a spray hole SH of a first diameter through which molten resin is sprayed, and disposed in a side direction of the mold clamping device 100;
A cylindrical barrel 220 on which the first injection nozzle 200 is detachably mounted and which has a transfer hollow (TC) inside that functions as a passage through which the resin can be transferred;
A hopper 230 coupled to the barrel 220 and configured to supply particulate resin to the transfer hollow (TC);
It is disposed in the transfer hollow (TC), and a transfer thread (TS) is formed on the outer surface, so that the resin can be transferred in the direction of the mold. The molten resin is pressed toward the mold, so that the molten resin is injected into the injection hole (SH). A screw 240 that allows spraying through;
Rotate the screw 240 to transfer the resin or move the screw 240 so that the molten resin is sprayed through the injection hole (SH) of the first diameter while being pressed by the screw 240. Actuator 250;
A heater 260 installed to contact the outer surface of the barrel 220 and for melting the resin in the transfer hollow (TC);
an advance/retractor 270 that advances and retracts the barrel 220 so that the first injection nozzle 210 is in contact with or spaced apart from the fixed mold 112 in the mold clamping device 100; and
A second spray nozzle (210) that can be replaced with the first spray nozzle (210) and be detachably mounted on the barrel (220) and has a spray hole (SH) of a second diameter through which molten resin is sprayed. Includes,
The first diameter and the second diameter are different from each other
Injection molding machine for producing ultra-large injection molded products. In paragraph 1
The first injection nozzle 210 is for double-sided molding,
The second injection nozzle 210 is for general molding,
the first diameter is larger than the second diameter
Injection molding machine for producing ultra-large injection molded products. In paragraph 2
The first diameter is 16 mm, and the second diameter is 8 mm or 12 mm.
Injection molding machine for producing ultra-large injection molded products. In paragraph 2
The first diameter is within the range of 133.33% to 200.00% of the second diameter.
Injection molding machine for producing ultra-large injection molded products.

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