KR20160088696A - Clamping apparatus of toggle type for injection molding machine - Google Patents

Abstract

The present invention relates to a toggle type clamping apparatus of an injection molding machine, having an improved structure capable of allowing a toggle link to be normally operated while a movable template is not pushed backward while driving in an injection compression mode. Disclosed is a toggle type clamping apparatus of an injection molding machine, comprising: a fixed template on which a fixed mold is mounted; a movable template installed to be able to move forward and backward with respect to the fixed template, wherein a movable mold corresponding to the fixed mold is mounted; a toggle instrument disposed between a toggle support, which is spaced apart from the rear of the movable template, and the movable template, to move the movable template, wherein the toggle instrument includes a cross head moving while coupled with a driving shaft operated by a clamping motor, and a link assembly coupled with the cross head and connecting the toggle support and the movable template to each other; and a hydraulic cylinder installed to support the cross head at the rear of the cross head and preventing toggle folding.

Description

Technical Field [0001] The present invention relates to a toggle type mold apparatus for an injection molding machine,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding machine, and more particularly, to a toggle molding machine of an injection molding machine having means for maintaining a mold opening state in an injection compression mode.

An injection molding machine injects a molten resin from an injection apparatus, charges it into a cavity of a mold apparatus, and solidifies it to mold the molded article. The mold apparatus comprises a stationary mold and a movable mold. Molding, mold clamping and mold clamping of the mold apparatus are performed by a mold clamping apparatus. The mold clamping apparatus includes a movable mold plate, a fixed mold plate, a drive source such as a motor for moving the movable mold plate, and a toggle mechanism.

The general injection mode of an injection molding machine is as follows. The movable mold plate of the mold clamping device, which is initially in the open state, is moved at a high speed in the direction of the fixed mold plate. When the movable mold provided on the movable mold plate is brought into contact with the fixed mold provided on the fixed mold plate according to the movement of the movable mold plate, the mold pressure is increased by increasing the pressure. Then, the nozzle of the injection apparatus is advanced to the mold, and the resin is injected and cooled. Thereafter, the movable mold plate of the mold clamping apparatus is retracted backward to separate the movable mold and the fixed mold, and finally the movable mold plate is retracted at a high speed to take out the injection molded article.

In this general injection mode, the gap between the movable mold and the stationary mold is not maintained in the mold closing and mold-clamping process, and the movable mold and the stationary mold are held in close contact with each other, and then the resin is injected. Therefore, it requires a large amount of force for a long time. In order to solve this problem, a fixed gap is maintained between the movable mold and the fixed mold in the mold closing process, and after a certain amount of resin is filled in the cavity space in the mold, the movable mold and the fixed mold are closely contacted with each other. Is used.

In the mold closing process, when the movable mold and the stationary mold are not in direct contact with each other and a constant gap is maintained, only a small mold force is required as compared with when the movable mold and the stationary mold are directly in close contact with each other. For example, when a gap of 0.1 mm or less is maintained between the movable mold and the stationary mold, a clamping force of about 95% of the mold clamping force is required when the movable mold and the stationary mold are closely contacted. When a gap of 0.5 mm is maintained between the movable mold and the stationary mold, a clamping force of about 70% of the mold clamping force is required when the movable mold and the stationary mold are closely contacted.

However, when the resin is injected while maintaining a constant gap between the movable mold and the stationary mold in the mold closing process, the movable mold may be pushed back by the injection pressure of the resin. That is, since the toggle link of the toggle type mold clamping device is not completely opened in a state in which a constant gap is maintained between the molds without directly contacting the movable mold with the fixed mold, the pressure of the resin filled in the mold cavity causes the movable mold plate The backward push phenomenon occurs. As a result, there is a phenomenon that a precise injection product is not molded, or the movable mold can not advance in the direction of the fixed mold, and no contact between the molds occurs at all. In addition, the toggle is not completely unfolded (folding), and so on.

It is an object of the present invention to provide a toggle-type mold clamping apparatus for an injection molding machine, which is improved in structure so that the movable mold plate is not pushed backward during operation of the injection compression mode and normally operates the toggle link .

It is another object of the present invention to provide a toggle-type mold clamping apparatus for an injection molding machine capable of performing injection compression of various thicknesses by preventing the movable mold plate from being pushed backward during driving in an injection compression mode.

According to an aspect of the present invention, A movable plate installed to be movable forward and backward with respect to the stationary plate and to which a movable mold corresponding to the stationary mold is mounted; A toggle support disposed behind the movable plate, a cross head positioned between the movable plate and moving the movable plate, coupled to a driving shaft operated by a mold-clamping motor, and coupled to the crosshead, A toggle mechanism having a toggle support and a link assembly connecting the movable plate to each other; And a hydraulic cylinder installed to support the crosshead at the rear of the crosshead to prevent a toggle folding phenomenon.

Wherein the hydraulic cylinder is provided with a first hydraulic cylinder and a second hydraulic cylinder which are symmetrical about the drive shaft, and the first hydraulic cylinder and the second hydraulic cylinder And may be disposed side by side with the drive shaft.

The hydraulic cylinder may be disposed on the upper, lower, left, or right side of the drive shaft.

Preferably, the hydraulic cylinder is a single-rod hydraulic cylinder positioned between the toggle support and the crosshead and supporting the crosshead with respect to the toggle support.

Wherein the rod ends of the first hydraulic cylinder and the second hydraulic cylinder are respectively connected to the crosshead through a joint and the joint of the first hydraulic cylinder and the joint of the second hydraulic cylinder are connected to the crosshead And can be disposed to face each other in the vertical direction.

When the gap between the movable mold and the stationary mold reaches a predetermined gap, the rod of the single-rod hydraulic cylinder advances to support the crosshead, and when the injection-molded article is taken out, So that the supporting force for the crosshead can be released.

The link assembly may include a short link and a long link coupled through a joint to connect the toggle support and the movable plate to each other, and a crosshead link coupling the cross head and the short link.

The link assembly may be symmetrically disposed on both sides of the crosshead.

According to another aspect of the present invention, A movable plate installed to be movable forward and backward with respect to the stationary plate and to which a movable mold corresponding to the stationary mold is mounted; A toggle support disposed behind the movable plate, a cross head positioned between the movable plate and moving the movable plate, coupled to a driving shaft operated by a mold-clamping motor, and coupled to the crosshead, A toggle mechanism having a toggle support and a link assembly connecting the movable plate to each other and having a pair symmetrically formed on both sides of the crosshead; And a hydraulic cylinder installed to support the pair of link assemblies in both directions to prevent a toggle folding phenomenon.

The link assembly may include a short link and a long link coupled through a joint to connect the toggle support and the movable plate to each other, and a crosshead link coupling the cross head and the short link.

Preferably, the hydraulic cylinder is a double-rod hydraulic cylinder in which ends of both rods are respectively coupled to the long links provided in the above-described link assembly.

Preferably, when the distance between the movable mold and the fixed mold reaches a predetermined gap, the rod of the two-rod hydraulic cylinder advances to support the pair of link assemblies in a direction in which they are widened, The rod of the two-rod hydraulic cylinder may be retracted to release the supporting force to the link assembly.

According to the present invention, when the movable mold and the stationary mold maintain a predetermined gap in the injection molding mode, the crosshead or the link assembly is supported by using the hydraulic cylinder and the gap is maintained. As a result, The link operates.

In addition, when the injection compression mode is operated, the movable mold plate is prevented from being pushed back, injection compression of various thicknesses can be performed, and the mechanism change can be minimized, so that the function of the mold clamping apparatus can be improved at low cost.

Therefore, when the present invention is applied, the mold clamping force of the toggle mechanism can be reduced by maintaining a constant gap between the movable mold and the stationary mold in the injection compression mode, thereby extending the mechanical life of the injection molding machine.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description of the invention given below, serve to further the understanding of the technical idea of the invention. And should not be construed as limiting.
1 is a view showing a configuration of a toggle type mold apparatus of an injection molding machine according to a preferred embodiment of the present invention.
Fig. 2 is a view showing a configuration of a single-rod hydraulic cylinder in Fig. 1. Fig.
3 is a view showing a configuration of a toggle type mold clamping apparatus of an injection molding machine according to another embodiment of the present invention.
Fig. 4 is a view showing the configuration of a double-rod hydraulic cylinder in Fig. 3. Fig.
5 is a flowchart illustrating an operation of the toggle type mold clamping apparatus of the injection molding machine according to the preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

1 is a view showing a configuration of a toggle type mold apparatus of an injection molding machine according to a preferred embodiment of the present invention.

1, a toggle type mold clamping apparatus for an injection molding machine according to a preferred embodiment of the present invention includes a stationary mold 100 on which a stationary mold 11 is mounted, a movable mold 12 corresponding to the stationary mold 11, A toggle mechanism 110 disposed between the toggle support 120 and the movable mold 101 to move the movable mold 101 and a mold opening / A first hydraulic cylinder 140 and a second hydraulic cylinder 150 which are provided.

The fixed plate 100 is fixed to the frame 103 as a stationary mold supporting apparatus and the movable plate 101 is installed behind the fixed plate 100 so as to be able to move forward and backward with respect to the fixed plate 100. A toggle support 120 is disposed at the rear of the movable plate 101 and a tie bar 120 is provided between the fixed plate 100 and the movable plate 101 to support the mold clamping force and guide the movement of the movable plate 101 Tie-bars 102 are provided.

The movable mold 101 is a movable mold holding apparatus which is installed opposite to the fixed mold 100 and is movable forward and backward along the tie bar 102. The movable mold 101 is moved by the operation of the toggle mechanism 110, Shape and opening operation. Here, the term "mold" means that the movable mold 101 is moved backward to move the movable mold 12 away from the stationary mold 11. The term "mold" refers to a state in which the movable mold 12 is separated from the stationary mold 11 until the parting face of the movable mold 12 contacts the parting face of the stationary mold 11 , And moving the movable mold (12) toward the stationary mold (11). In this state, the first mold clamping force is set as the mold clamping force. When the crosshead 111 is driven by the mold body motor 130 as a driving unit, the link assembly 112 of the toggle mechanism 110 is unfolded and the mold is closed. The term " mold " means that the stationary mold 11 is in contact with the movable mold 12 by applying more force to the movable mold 12. [ In this state, a second mold clamping force larger than the first mold clamping force is set as the mold clamping force, and the mold clamping operation is performed at a speed lower than the mold clamping speed.

The mold member 10, which is the portion to which the resin is injected, is composed of the stationary mold 11 and the movable mold 12. [ The stationary mold 11 is mounted on a mold mounting surface opposed to the movable mold 101 in the stationary mold 100 and the movable mold 12 is mounted on the mold 101 opposed to the stationary mold 100 in the movable mold 101, Mounted on the mounting surface.

A toggle mechanism 110 is provided between the movable mold plate 101 and the toggle support 120. Further, a mold-shaped motor 130 is provided as a drive source for mold clamping to operate the toggle mechanism 110 at the rear end of the toggle support 120. [ The mold-clamping motor 130 provides a driving force to the toggle mechanism 110 by operating the driving shaft 132 via a predetermined power switching mechanism 131. Here, as the drive shaft 132, a ball screw shaft may be preferably employed. Here, the mold-shaped motor 130 is preferably a servo motor and has a mold opening / closing position sensor (not shown) as an encoder for detecting the number of revolutions.

The toggle mechanism 110 receives the power generated by the mold clamping motor 130 and moves the movable mold plate 101 back and forth. To this end, the toggle mechanism 110 includes a crosshead 111 which is coupled to the drive shaft 132 and is movable with respect to the toggle support 120 and the movable plate 101, And a link assembly (112) for connecting to each other.

The crosshead 111 is coupled to the drive shaft 132 and moves forward and backward in conjunction with the movement of the drive shaft 132. That is, when the crosshead 111 advances (moves in the right direction in FIG. 1), the movable plate 101, which is the driven portion, moves forward via the link assembly 112 to be closed. At this time, a clamping force is generated by multiplying the driving force by the mold clamping motor 130 by the toggle magnification, and the mold clamping force is applied by the clamping force.

The link assembly 112 includes an end link 112a and a longitudinal link 112b for connecting the toggle support 120 and the movable plate 101 to each other and a pair of link members 112a, And a crosshead link 112c for ringing. Here, the short link 112a and the long link 112b may be coupled in series to each other through a joint. It is preferable that a pair of link assemblies 112 are arranged symmetrically on both sides of the crosshead 111 at the upper and lower sides (or the left and right sides).

The first hydraulic cylinder 140 and the second hydraulic cylinder 150 support the crosshead 111 at the rear of the crosshead 111 to prevent the toggle link from being folded when driven in the injection compression mode. Preferably, the first hydraulic cylinder 140 and the second hydraulic cylinder 150 are positioned between the toggle support 120 and the crosshead 111. In this case, the rear end of the body is supported by the toggle support 120, and the ends of the respective rods 141 and 151 are connected to each other by a joint (not shown). In this case, the first hydraulic cylinder 140 and the second hydraulic cylinder 150 employ a single- A and B to support the crosshead 111 relative to the toggle support 120 to prevent the crosshead 111 from being pushed backward.

The first hydraulic cylinder 140 and the second hydraulic cylinder 150 are arranged symmetrically with respect to the drive shaft 132. That is, the first hydraulic cylinder 140 and the second hydraulic cylinder 150 And is disposed on the upper, lower, left, and right portions of the drive shaft 132. [ In addition, the hydraulic cylinder 140 is preferably disposed in parallel with the drive shaft 132 so as to apply a bearing force opposite to the direction in which the crosshead 111 is pushed. Here, the joint A of the first hydraulic cylinder 140 and the joint B of the second hydraulic cylinder 150 are disposed to face each other in the vertical direction with respect to the crosshead 111.

As shown in Fig. 2, the first hydraulic cylinder 140 and the second hydraulic cylinder 150 are moved by the operation of the hydraulic valve a to a movement path for the oil 1 supplied as a working fluid to the cylinder heads 142 and 152 It is possible to selectively provide the function of the rods 141 and 151 to support the crosshead 111. The first hydraulic cylinder 140 and the second hydraulic cylinder 150 As a rod hydraulic cylinder to be implemented, a normal product can be adopted, and a detailed description thereof will be omitted.

3 shows a configuration of a toggle type mold apparatus of an injection molding machine according to another embodiment of the present invention. In this embodiment, the hydraulic cylinder 160 supports a pair of link assemblies 112 symmetrically disposed on both sides of the crosshead 111 in both directions , that is, in a direction in which a pair of link assemblies are opened. Here, the pair of link assemblies 112 may be disposed on the upper, lower, left, and right sides of the crosshead 111.

The hydraulic cylinder 160 is provided with two rod hydraulic cylinders 160 and 160 which are substantially coupled to the long links 112b of the pair of link assemblies 112 via joints C and D, respectively, Is preferably employed. The joints C and D to which the two rods 161 and 162 of the hydraulic cylinder 160 are respectively connected are connected to each other in the vertical direction by the hydraulic cylinder 160, . The joints C and D to which the two rods 161 and 162 are respectively connected are preferably connected to the long link 112b in order to efficiently support a pair of link assemblies 112 in operation of the hydraulic cylinder 160 Do. That is, when the hydraulic cylinder 160 is operated, toward the retreat direction of the long link 112b The both rods 161 and 162 move up and down respectively to apply a supporting force to the long link 112b. As described above, it is possible to prevent the joining of the link assembly 112 by providing a pressing force to the end before the bending of the toggle link.

As shown in Fig. 4, the hydraulic cylinder 160 opens and closes the movement path for the oil 1 supplied as the working fluid to the cylinder head 163 by the operation of the hydraulic valve a, Can selectively provide the function of supporting the long links 112b of the link assemblies 112, respectively. As the two-rod hydraulic cylinder for implementing the hydraulic cylinder 160, an ordinary product can be employed, and thus a detailed description thereof will be omitted.

5 is a flowchart illustrating an operation of the toggle type mold clamping apparatus of an injection molding machine according to a preferred embodiment of the present invention.

Referring to FIG. 5, the injection molding machine receives gap information between the fixed mold 11 and the movable mold 12 in the injection compression mode through a predetermined control device included therein and sets the gap information (S100). The gap is, for example, between 0.1 mm and 0.5 mm.

Next, the injection molding machine drives the mold-clamping motor 130 to perform a mold closing operation to move the movable mold 101 in the direction of the fixed mold 100 (S110). That is, the mold-shaped motor 130 pushes the crosshead 111, and the link assembly 112 of the toggle mechanism 110 is unfolded, thereby closing the mold.

The injection molding machine checks the gap between the movable mold 12 and the fixed mold 11 while moving the movable mold 101 in the direction of the fixed mold 100 and checks whether the gap reaches the gap set in the step S100 S120). That is, it is confirmed whether the positions of the movable mold 12 and the stationary mold 11 reach the position of the gap. When the gap between the movable mold 12 and the fixed mold 11 reaches the gap set in the step S100, the injection molding machine operates the hydraulic cylinders 140, 150 and 160 to provide a supporting force. 1, the hydraulic valve a is operated by the control device so that the rod 141 of the first hydraulic cylinder 140 and the rod 151 of the second hydraulic cylinder 150 operate at the same time And supports the crosshead 111 in the pushing direction by advancing. In the case of the toggle type mold clamping apparatus shown in Fig. 3, the hydraulic valve a is operated by the control device so that the two rods 161 and 162 of the hydraulic cylinder 160 are simultaneously advanced to move the pair of link assemblies 112 in the opening direction (Step S130). Therefore, the folding of the toggle link is prevented, and the movable plate 101 is prevented from being pushed back by the injection pressure of the resin.

Subsequently, the injection molding machine injects the molten resin into the cavities in the molds 11 and 12 (S140). When the molten resin is filled in the cavity by a predetermined threshold value, the injection molding machine drives the mold motor 130 to move the movable mold 101 in the direction of the fixed mold 100 to move the movable mold 12 and the stationary mold 11 (S160). That is, when the molten resin is filled in the molds 11 and 12 by a certain amount in a state where a constant gap between the movable mold 12 and the stationary mold 11 is maintained, the toggle type mold clamping apparatus performs a mold clamping operation.

In a state in which the movable mold 12 and the stationary mold 11 are in close contact with each other, the injection molding machine completes the injection of the molten resin into the remaining space of the cavities in the molds 11 and 12 and takes out the injection molded product ).

Subsequently, the injection molding machine operates the hydraulic cylinders 140, 150 and 160 to release the supporting force (S180). 1, the hydraulic valve a is operated by the control device so that the rod 141 of the first hydraulic cylinder 140 and the rod 151 of the second hydraulic cylinder 150 operate at the same time Thereby releasing the supporting force applied to the crosshead 111 by retreating. In the case of the toggle type mold clamping apparatus shown in Fig. 3, the hydraulic pressure valve a is operated by the control device, so that the support forces applied to the pair of link assemblies 112 by the both rods 161 and 162 of the hydraulic cylinder 160 are retracted simultaneously Release.

As described above, the support force is released, When the crosshead 111 is pulled backward by driving the mold body motor 130 as a driving unit, the mold assembly operation is performed while the link assembly 112 of the toggle mechanism 110 is folded (S190).

As described above, the toggle type mold clamping apparatus of the injection molding machine according to the present invention is characterized in that when the movable mold 12 and the stationary mold 11 maintain a constant gap during the operation of the injection compression mode, the cross heads 111 Or the link assembly 112 is supported to maintain the gap so that the movable plate 101 can be normally injected without being pushed back.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not to be limited to the details thereof and that various changes and modifications will be apparent to those skilled in the art. And various modifications and variations are possible within the scope of the appended claims.

11: stationary mold 12: movable mold
100: fixed plate 101: movable plate
102: Tie bar 103: Frame
110: toggle mechanism 111: crosshead
112: link assembly 112a:
112b: chapter link 112c: crosshead link
120: toggle support 130: shaped motor
131: Power switching mechanism 132: Driving shaft
140: first hydraulic cylinder 150: second hydraulic cylinder
160: Hydraulic cylinder A, B, C, D: Joint

Claims (12)

A fixed plate on which a stationary mold is mounted;
A movable plate installed to be movable forward and backward with respect to the stationary plate and to which a movable mold corresponding to the stationary mold is mounted;
A toggle support disposed behind the movable plate, a cross head positioned between the movable plate and moving the movable plate, coupled to a driving shaft operated by a mold-clamping motor, and coupled to the crosshead, A toggle mechanism having a toggle support and a link assembly connecting the movable plate to each other; And
And a hydraulic cylinder installed to support the crosshead at a rear side of the crosshead to prevent a toggle folding phenomenon. The method according to claim 1,
Wherein the hydraulic cylinder is provided with a first hydraulic cylinder and a second hydraulic cylinder which are symmetrical about the drive shaft, and the first hydraulic cylinder and the second hydraulic cylinder Wherein the driving shaft is disposed in parallel with the driving shaft. 3. The method of claim 2,
Wherein the hydraulic cylinder is disposed at an upper portion, a lower portion, a left, and a right portion of the drive shaft. The method of claim 3,
Said hydraulic cylinder being located between said toggle support and said crosshead,
Wherein the toggle support is a single-rod hydraulic cylinder that supports the crosshead with respect to the toggle support. 5. The method of claim 4,
The rod ends of the first hydraulic cylinder and the second hydraulic cylinder are connected to the crosshead through joints, respectively,
Wherein a joint of the first hydraulic cylinder and a joint of the second hydraulic cylinder are disposed with respect to the crosshead Wherein the molds are arranged to face each other in the vertical direction. 5. The method of claim 4,
When the gap between the movable mold and the fixed mold reaches a predetermined gap, the rod of the single-rod hydraulic cylinder advances to support the crosshead,
Wherein the rod of the single-rod hydraulic cylinder is retracted to release the supporting force with respect to the cross-head when the injection-molded article is taken out after the take-off operation. The link assembly of claim 1,
And a crosshead link coupled to the toggle support and the movable plate, the cross link connecting the cross link and the long link, and the crosshead link coupling the cross head and the end link. Shaped device. 8. The method of claim 7,
Wherein the link assembly is symmetrically disposed on both sides of the crosshead. ≪ RTI ID = 0.0 > 8. < / RTI > A fixed plate on which a stationary mold is mounted;
A movable plate installed to be movable forward and backward with respect to the stationary plate and to which a movable mold corresponding to the stationary mold is mounted;
A toggle support disposed behind the movable plate, a cross head positioned between the movable plate and moving the movable plate, coupled to a driving shaft operated by a mold-clamping motor, and coupled to the crosshead, A toggle mechanism having a toggle support and a link assembly connecting the movable plate to each other and having a pair symmetrically formed on both sides of the crosshead; And
And a hydraulic cylinder installed to support the pair of link assemblies in both directions to prevent a toggle folding phenomenon. 10. The link assembly of claim 9,
And a crosshead link coupled to the toggle support and the movable plate, the cross link connecting the cross link and the long link, and the crosshead link coupling the cross head and the end link. Shaped device. 11. The method of claim 10,
Wherein said hydraulic cylinder is a double-rod hydraulic cylinder in which ends of both rods are respectively coupled to said long links provided in said pair of link assemblies. 12. The method of claim 11,
When the gap between the movable mold and the fixed mold reaches a predetermined gap, the rod of the both-rod hydraulic cylinder advances to support the pair of link assemblies in a direction in which they are widened,
Wherein the rod of the two-rod hydraulic cylinder is retracted to release the supporting force to the link assembly when the injection-molded article is taken out after the take-off operation.

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