JP7352177B2 - Sub injection device - Google Patents

Description

The present invention relates to a sub-injection device that is disposed in a direction perpendicular to the opening and closing direction of a mold attached to an injection molding machine and injects and fills the mold with molten resin.

In an injection molding machine equipped with a mold clamping device and an injection device, after the mold is clamped by the mold clamping device, melt is injected from the injection device into a cavity (a space imitating the shape of a molded product) formed in the mold. This is a device that molds (manufactures) molded products by injecting (injection filling) resin at a predetermined pressure. In recent years, all-electric injection molding machines in which both the mold clamping device and the injection device are driven by electric motors such as servo motors have become mainstream because of their excellent controllability.

BACKGROUND ART Injection molding machines in which two or more injection devices having the same size and specifications are arranged are conventionally known. However, in recent years, as the demands for molded products have diversified, a separate injection device (hereinafter referred to as a sub-injection device) has been placed in the injection molding machine to perform injection filling from the injection device of the injection molding machine. There is an increasing demand for laminate molded products that are partially laminated onto the base material molding section by injecting resins of different types and colors from a sub-injection device into the base material molding section. Such partial lamination is intended to improve the design of the molded product, improve strength, heat resistance, cold resistance, weather resistance, etc., or provide functions such as anti-slip and scratch resistance.

The sub-injection device employed for molding such a laminate molded product has a smaller injection filling amount than the injection device of the injection molding machine. In addition, since the injection filling amount is small, it is preferable that the resin flow path to the laminated part in the mold is short, and the resin filling hole (hereinafter referred to as sprue bushing) is placed on the mold surface as close as possible to the laminated part. It is preferable to arrange. The sub-injection device is fixed to an injection molding machine, a mold, etc. in various forms corresponding to these sprue bushes. As a result, the sub-injection device is often an all-electric injection device that is smaller and lighter than the injection device of the injection molding machine.

Various ways of fixing the sub-injection device include a mode in which the sub-injection device is fixed to a mold, and a mode in which the sub-injection device is fixed to a supporting member disposed on the top surface of a stationary plate or a tie bar. However, at the stage of considering the adoption of a sub-injection device or at the stage of prototyping a molded product, a simple arrangement is often adopted that does not require major mechanical modification of the injection molding machine itself.

An example of such a conventional and simple arrangement of the sub-injection device will be explained with reference to FIG. 1. FIG. 1A is a schematic plan view showing an arrangement in which the sub-injection device 120 is arranged in a direction perpendicular to the opening/closing direction of a mold 36 attached to the injection molding machine 10 and injects and fills the mold 36 with molten resin. It is. FIG. 1(b) is a view taken along the line AA in FIG. 1(a), and shows a state in which the sub-injection cylinder 121 of the sub-injection device 120 is at the backward limit position. FIG. 1(c) shows a state in which the nozzle of the sub-injection cylinder 121 is brought into contact with the sprue bushing 36d on the side surface of the fixed mold 36a from the state shown in FIG. 1(b). The nozzle touch will be described later.

First, a general injection molding machine 10 will be explained. The mold clamping device 30 includes a fixed platen 33 and a movable platen 34 arranged on a base 32. Then, by a mold clamping mechanism 35 such as a toggle link mechanism, the movable platen 34 movably disposed on the base 32 is moved toward and away from the fixed platen 33 fixed to the base 32, and each The molds 36 (fixed mold 36a, movable mold 36b) mounted opposite to the board are opened and closed (mold opening/closing), and the fixed mold 36a and movable mold 36b in the mold closed state are applied with a predetermined force (mold clamping force). ) to tighten the mold.

Further, the fixed platen 33 and a pressure receiving plate (not shown) (called a link housing or the like when the mold clamping mechanism 35 is a toggle link mechanism) are connected at their respective four corners by tie bars 37. Tie bars 37 pass through the four corners of the movable plate 34 disposed between the fixed plate 33 and the pressure receiving plate, and movement in the mold opening/closing direction on the base 32 is guided by the tie bars 37.

The injection device 20 includes an injection cylinder 21 and a base 22, and the injection cylinder 21 internally melts (plasticizes) the supplied resin material, and also melts (plasticizes) the supplied resin material inside a fixed mold 36a and a movable mold 36b which are integrated by mold clamping. Molten resin is injected and filled into the cavity 36c from a sprue bush (not shown) of the fixed mold 36a at a predetermined pressure and filling speed. Therefore, the injection cylinder 21 is installed on a base 22 disposed on the opposite side of the fixed mold 36a with respect to the fixed platen 33 via a moving device (not shown), and has an opening 33a passing through the fixed platen 33. Through the moving device, the injection cylinder 21 can be moved toward and away from the fixed mold 36a.

With this configuration, the injection device 20 can bring the nozzle 21a at the tip of the injection cylinder 21 closer to, press against, and move away from the sprue bush of the fixed mold 36a. Pressing the tip of the nozzle 21a of the injection cylinder 21 against the sprue bush of the fixed mold 36a with a predetermined force is called nozzle touch. Further, during injection filling with the nozzle touching, the injection reaction force caused by injecting and filling the molten resin from the injection cylinder 21 into the cavity 36c acts in a direction to separate the nozzle 21a of the injection cylinder 21 from the sprue bushing. . The above-mentioned pressing force required to maintain the nozzle touch state against this injection reaction force that the injection cylinder 21 (injection device 20) receives is called nozzle touch force.

In addition, in addition to the above-mentioned moving device (not shown) for nozzle touch, the injection cylinder including the above-mentioned moving device can be used to accurately touch the nozzle 21a of the injection cylinder 21 to the sprue bush of the fixed mold 36a. Generally, a nozzle centering mechanism (not shown) is provided that can adjust the position of the injection cylinder 21 in horizontal and vertical directions perpendicular to the longitudinal direction of the injection cylinder 21.

Next, the sub-injection device 120 will be explained. The sub-injection device 120 includes a sub-injection cylinder 121 and a sub-base 122. Then, the molten resin is injected into a sprue bush 36d formed on the side surface of the fixed mold 36a and arranged in a direction perpendicular to the opening/closing direction of the mold 36 attached to the injection molding machine 10. It is assumed that the sub-injection cylinder 121 of the sub-injection device 120 has basically the same structure as the injection cylinder 21 of the injection device 20, and only the differences between the injection device 20 and the injection cylinder 21 will be explained.

A sub-injection cylinder 121 is arranged above the sub-base 122. Between the sub-injection cylinder 121 and the sub-base 122, the sub-injection cylinder 121 is supported so as to be movable in a direction orthogonal to the opening/closing direction of the mold 36. In other words, the nozzle touch of the sub-injection cylinder 121 is A sub-moving device 123 is arranged. Further, the side surface of the fixed mold 36a and the sub-moving device 123 are connected by one connecting member 124.

One connecting member 124 is not shown in FIG. 1(a) because it is disposed coaxially with and below the injection center axis of the sub-injection cylinder 121 in the plan view (FIG. 1(a)). Further, the connecting member 124 is arranged parallel to the injection center axis of the sub-injection cylinder 121 in the side view (FIGS. 1(b) and 1(c)). When the side surface of the fixed mold 36a and the sub-moving device 123 are connected by one connecting member 124, such an arrangement of the connecting member 124 is preferable.

On the other hand, although not shown, if it is difficult to arrange the connecting member 124 as described above due to the position of the cavity 36c with respect to the fixed mold 36a or the arrangement of the resin flow path (sprue) in the fixed mold 36a, etc. , the side surface of the fixed mold 36a and the sub-moving device 123 may be connected by two connecting members 124. In this case, it is preferable that each connecting member 124 be arranged on the same plane, parallel to and at equal distances from the injection center axis of the sub-injection cylinder 121. Furthermore, even if it is difficult to arrange the connecting members 124 like this, at least each connecting member 124 should be parallel to the injection center axis of the sub-injection cylinder 121 and at equal distances from the injection center axis. It is preferable that the

The sub-movement device 123 employs a linear guide or a known linear movement guide mechanism. Similarly to the injection device 20, the position of the sub-injection cylinder 121 including the sub-movement device 123 is adjusted in the horizontal direction (opening/closing direction of the mold 36) orthogonal to the longitudinal direction of the sub-injection cylinder 121 and in the vertical direction (vertical direction). ) is arranged with an adjustable nozzle centering mechanism 129. To adjust the position of the nozzle centering mechanism 129 in the horizontal direction, a linear guide or a known linear movement guide mechanism may be used, and to adjust the position in the vertical direction, a jack bolt or a known height adjustment mechanism can be used. It is fine if it is done. Small wheels (casters) are arranged below the sub-base 122. It is preferable that some or all of the plurality of casters are rotatable and equipped with a wheel rotation stopper.

In order to arrange the sub-injection device 120 on the machine side of the injection molding machine 10, first, the sub-base 122 is placed so that the nozzle 121a of the sub-injection cylinder 121 can touch the sprue bushing 36d on the side of the fixed mold 36a. It is moved onto the machine side foundation of the molding machine 10 and temporarily positioned. The temporary positioning of the sub-base 123 with respect to the fixed mold 36a is performed with a predetermined accuracy using a connecting member 124 that connects the side surface of the fixed mold 36a and the sub-moving device 123, that is, the nozzle touch of the sub-injection cylinder 121 by the nozzle centering mechanism 129. Accuracy that allows position adjustment can be ensured. Fixed parts such as flanges are formed at both ends of the connecting member 124, and each fixed part is connected to the side surface of the fixed mold 36a and the sub-moving device 123 with bolts or the like. If it is difficult to connect the connecting member 124, finely adjust the arrangement of the sub-base 122. After the connection of the connection member 124 is completed and the temporary positioning of the sub-base 122 is completed, the wheels are prevented from rotating by the rotation stopper.

Thereafter, the sub-injection cylinder 121 is manually moved toward the fixed mold 36a, and the nozzle centering mechanism 129 moves the sub-injection cylinder 121 so that the nozzle 121a of the sub-injection cylinder 121 can touch the sprue bushing 36d on the side of the fixed mold 36a. The position of the sub-injection cylinder 121 including the moving device 123 is adjusted. Further, in parallel with this, work is performed to electrically connect the control device (not shown) of the sub-injection device 120 and the control device (not shown) of the injection molding machine 10. After confirming that the nozzle 121a of the sub-injection cylinder 121 can touch the sprue bushing 36d on the side of the fixed mold 36a, power is applied to check the operation of the sub-injection device 120 alone, and then the interlocking with the injection molding machine 10 is confirmed. confirm.

Here, at the stage of considering the adoption of a sub-injection device, various settings of the injection molding machine 10, such as molding conditions of the injection device 20 and sub-injection device 120, are changed each time while checking the molded product each time. It is common to make a prototype of a molded product (molding trial). Therefore, as shown in FIG. 1C, after manually touching the nozzle of the sub-injection cylinder 121 and confirming the nozzle touch state, use a known mechanical stopper 125 such as a clamp to position the sub-injection cylinder 121 with respect to the sub-movement device 123. to be fixed. After completing all the operation checks and preparations, a molding trial is carried out.

In the simple arrangement of the sub-injection device 120 described above, mechanical modification of the injection molding machine 10 is almost unnecessary. That is, it is only necessary to prepare the mold 36 for lamination molding that includes the sprue bush 36d for the sub-injection device 120. Moreover, since the sub base 122 of the sub injection device 120 is provided with casters and is movable, temporary positioning of the sub injection device 120 with respect to the injection molding machine 10 is easy.

Then, the injection reaction force acting on the sub-injection cylinder 121 (sub-injection device 120) is received by the fixed mold 36a (mold 36) in a clamped state via the connecting member 124. Therefore, not only is it not necessary to provide a portion on the side of the injection molding machine 10 that receives this injection reaction force, but there is also no need to support the injection reaction force on the side of the sub base 122 of the sub injection device 120. Therefore, the sub-base 122 only needs to have a rigidity that can support the weight of the sub-injection cylinder 121 and other parts, as well as the dynamic load and moment of movable parts such as the screw in the injection cylinder during injection filling, and It can be made lightweight and movable on casters. Even when the sub-base 122 is fixed to the foundation with an anchor or the like, there is no need for strong fixation using a chemical anchor that requires advance construction, a large anchor, or the like. It is sufficient to fix the sub-injection device 120 with a small anchor such as a hole-in anchor that can be installed when installing the sub-injection device 120, and the sub-injection device 120 can be easily installed and removed.

In addition to the configuration shown in FIG. 1, there is a configuration in which the sub-injection device is arranged in a direction perpendicular to the opening/closing direction of the mold. A configuration in which the second moving mechanism 60 of the sub-injection device (second injection device 40) is connected to the injection molding device 10 via the attached third rail 65 and third slider 64 (Patent Document 1/FIG. 1- 4) is disclosed.

Furthermore, a form (Patent Document 2/FIGS. 1 to 4) in which a sub base 20 of a sub injection device 18 is connected to a connection unit 22 provided on the upper surface of a machine base (machine stand 16) of an injection molding machine 10 is disclosed. ing.

Japanese Patent Application Publication No. 2016-078384 JP2017-222031A

The simple arrangement of the sub-injection device 120 in the injection molding machine 10 shown in FIG. It is. On the other hand, operations other than the nozzle touch operation and the fixing of the sub-injection cylinder 121 to the sub-movement device 123 in the nozzle-touched state can be performed using a control device or an operation panel (operation pendant) dedicated to the sub-movement device 123. Therefore, there is a demand for making the nozzle touch operation similarly operable. However, when the sub-injection cylinder of the sub-injection device is equipped with a nozzle touch mechanism including a drive source, there is a problem that the configuration of the sub-injection device becomes complicated.

Further, the injection molding apparatus of Patent Document 1 is configured to receive injection reaction force by two members (first bridge material 66, second bridge material 73, etc.) passed between two upper and lower tie bars. Therefore, it is necessary to mechanically modify the injection molding machine by attaching these parts to the injection molding machine. The injection molding apparatus of Patent Document 1 uses the rod 61 (substantially a fluid cylinder) for driving the nozzle touch operation of the second injection machine 40 and the above two members to apply the injection reaction force to two upper and lower parts. The configuration is such that the information is transmitted to the tie bar.

In the above configuration, one end of the rod 61 is horizontally slidably fixed to the third rail 65 disposed between the two members (paragraph 0033 of Patent Document 1, etc., FIGS. 3, 4, and 6). Here, in the embodiment described above, the third rail 65 is fixed at approximately the same height as the lower tie bar, and is not fixed at a position between the two members and between the upper and lower tie bars. This is because in order to receive the injection reaction force at the intermediate position between the upper and lower tie bars of the above two members, it is necessary to ensure the strength of the above two members (first bridge member 66, second bridge member 73, etc.) It is assumed that. At least, Patent Document 1 does not suggest or illustrate a form in which the third rail 65 is fixed between the two members and at an intermediate position between the upper and lower tie bars.

As mentioned above, in the injection molding apparatus of Patent Document 1, the third rail 65 needs to be fixed at approximately the same height as the lower tie bar. As a result, the rod 61 is arranged largely eccentrically from the injection filling axis of the second injection machine 40, and an injection reaction force component acting in a direction that is not parallel to the nozzle touch direction acts on the second slider 44 of the second injection machine 40. There is a problem with doing so. Furthermore, in order to reduce this eccentric distance, there is a restriction on the sprue bushing position of the mold that the sprue bushing, which the second injection machine 40 touches with its nozzle, must be placed as far down as possible from the side surface of the fixed mold.

On the other hand, in the injection molding machine of Patent Document 2, the sub base 20 on which the sub injection device 18 is arranged is connected to the connection unit 22 arranged on the upper surface of the base 16 (machine base) of the injection molding machine 10. , mechanical modification of the injection molding machine is required. Furthermore, since the sub-injection device is equipped with a nozzle touch mechanism including a drive source, there is a problem that the configuration of the sub-injection device becomes complicated.

The present invention has been made in view of the above-mentioned problems, and does not require mechanical modification of the injection molding machine, does not complicate the configuration even when equipped with a nozzle touch function equipped with a drive source, and does not require injection molding. It is an object of the present invention to provide a sub-injection device that can receive force with a mold.

The above object of the present invention is to provide a sub-injection device that is arranged in a direction perpendicular to the opening and closing direction of a mold attached to an injection molding machine and injects and fills the mold with molten resin,
a sub-base placed on the foundation and having a sub-injection cylinder placed above;
a sub-moving device that is disposed between the sub-injection cylinder and the sub-base and supports the sub-injection cylinder so as to be movable in a direction perpendicular to the opening/closing direction of the mold;
a connecting member connecting a fixed side surface of the mold and the sub-injection cylinder;
Equipped with
This is achieved by a sub-injection device characterized in that a part or all of the connecting member is composed of a fluid cylinder.

Further, in the sub-injection device according to the present invention, it is preferable that the connecting member includes at least one sliding permitting portion that allows a predetermined amount of movement in the entire circumferential direction orthogonal to the direction of expansion and contraction of the fluid cylinder. .

On the other hand, in the sub-injection device according to the present invention, the fluid cylinder is expanded and contracted by a fluid circuit connected to a rod side chamber and a head side chamber of the fluid cylinder, and the sub-injection to the fixed side sprue bushing is performed. It is preferable that the nozzles of the cylinders are brought closer and separated, and that the fluid circuit is configured to be able to suppress expansion of the fluid cylinder during injection and filling by the sub-injection cylinder.

Here, in the fluid circuit, the expansion of the fluid cylinder during injection filling may be suppressed by maintaining a predetermined pressure in a rod side chamber of the fluid cylinder, and a rod side chamber and a head side chamber of the fluid cylinder. This may be done by blocking the conduits connected to both.

The sub-injection device according to the present invention is a sub-injection device that is arranged in a direction perpendicular to the opening and closing direction of a mold attached to an injection molding machine, and injects and fills the mold with molten resin,
a sub-base placed on the foundation and having a sub-injection cylinder placed above;
a sub-moving device that is disposed between the sub-injection cylinder and the sub-base and supports the sub-injection cylinder so as to be movable in a direction perpendicular to the opening/closing direction of the mold;
a connecting member connecting a fixed side surface of the mold and the sub-injection cylinder;
Equipped with
Since some or all of the connecting members are composed of fluid cylinders, there is no need to mechanically modify the injection molding machine, the configuration does not become complicated even when equipped with a nozzle touch function equipped with a drive source, and the injection reaction force is reduced. can be received in a mold.

It is a figure which shows an example of the conventional simple arrangement of a sub-injection device. FIG. 2 is a schematic side view of the sub-injection device according to the first embodiment. FIG. 3 is a detailed diagram of a main part X in FIG. 2; FIG. 3 is a detailed view of main part Y in FIG. 2; 4 is a diagram showing another form of FIG. 3. FIG. FIG. 2 is a schematic fluid circuit diagram of a fluid cylinder of the sub-injection device according to the first embodiment. 7 is a schematic fluid circuit diagram showing a state in which the solenoid valve is activated in FIG. 6. FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

[First embodiment]
A sub-injection device 220 according to a first embodiment of the present invention will be described with reference to FIGS. 2 to 7. FIG. 2(a) corresponds to FIG. 1(b) of the conventional sub-injection device 120, and shows a state in which the sub-injection cylinder 221 of the sub-injection device 220 is at the backward limit position. FIG. 2(b) corresponds to FIG. 1(c) of the conventional sub-injection device 120, in which the sub-injection cylinder 221 is brought into contact with the sprue bushing 36d on the side surface of the fixed mold 36a from the state shown in FIG. 2(a). Indicates the condition. Note that the sub-injection device 220 according to the first embodiment differs from the conventional sub-injection device 120 only in the connection member 124 that connects the side surface of the fixed mold 36a and the sub-movement device 123, and the connection form thereof. Therefore, in the following description, the same components as those of the conventional sub-injection device 120 will be given the same reference numerals and explanations will be omitted, and only the different components will be explained.

In the sub-injection device 220, some or all of the connecting members are configured with fluid cylinders. In the first embodiment, as shown in FIG. 2(a), the connecting member 224 includes a fluid cylinder 225 and a connecting auxiliary member 226. Further, the side surface of the fixed mold 36a is connected to the sub-injection cylinder 221 instead of the sub-moving device 123 by the connecting member 224. The fluid cylinder 225 is an air cylinder, and its cylinder rod 225a side is connected to the side surface of the fixed mold 36a, and its cylinder body 225b side is connected to the sub-injection cylinder 221 via a connection auxiliary member 226.

As for the fluid cylinder 225, a fluid circuit (pneumatic circuit) as shown in FIG. Become the source. The fluid circuit will be described later. By configuring the connecting member 124 of the conventional sub-injecting device 120 with such a connecting member 224, the sub-injection device 220 according to the first embodiment can be configured even if equipped with a nozzle touch function provided with a drive source. It is not complicated and the injection reaction force can be received by the mold. Furthermore, it goes without saying that no mechanical modification of the injection molding machine is required.

Here, in the sub-injection device 220, the connecting member 224 is provided with at least one sliding permitting portion 227 that allows the fluid cylinder 225 to move by a predetermined amount in the entire circumferential direction orthogonal to the direction of expansion and contraction of the fluid cylinder 225. In the first embodiment, the cylinder rod 225a of the fluid cylinder 225 is connected to the side surface of the fixed mold 36a via the sliding portion 227 (main portion X in FIG. 2(a)). The sliding permitting portion 227 will be explained with reference to FIG. 3. 3(a) is a detailed view of the main part X in FIG. 2, and FIG. 3(b) is a view taken along the line BB in FIG. 3(a).

A tip member 227a and a rod tip nut 225c are screwed and fixed to the tip of the cylinder rod 225a with a double nut. The tip member 227a is a pulley-shaped member in which a large diameter portion is coaxially arranged on both end faces of a small diameter portion. On the other hand, a fixing member 227b is fixed with a bolt or the like to the side surface of the fixed mold 36a corresponding to the cylinder rod 225a. An opening hole is formed in the center of the fixing member 227b, the diameter of which is larger than the outer diameter of the small diameter portion of the tip member 227a and smaller than the outer diameter of the large diameter portion. One of the large diameter parts of the tip member 227a is configured to be separable and fixed to the small diameter part, and as shown in FIG. It is incorporated into the fixing member 227b so as to pass through the hole.

Between the large diameter portion of the tip member 227a and the fixed member 227b facing the large diameter portion, a predetermined amount of movement of the tip member 227a is allowed in the entire circumferential direction orthogonal to the direction of expansion and contraction of the fluid cylinder 225. Clearance CL2 is secured for this purpose. Although the clearance CL2 is exaggerated in order to make the diagram easier to understand, it is only necessary to ensure a minimum clearance that allows the tip member 227a to move in the entire circumferential direction with respect to the fixed member 227b. .

On the other hand, a clearance CL1 is secured in the radial direction between the inner circumferential surface of the opening of the fixing member 227b and the outer circumferential surface of the small diameter portion of the tip member 227a. With this configuration of the fixing member 227, the position of the tip of the cylinder rod 225a of the fluid cylinder 225 with respect to the fixed mold 36a is maintained (connected) in the direction of expansion and contraction of the fluid cylinder 225. Furthermore, movement of the clearance CL1 is allowed in the entire circumferential direction orthogonal to the direction of expansion and contraction of the fluid cylinder 225.

Here, the position adjustment for the nozzle touch of the sub-injection cylinder of the sub-injection device is performed by adjusting the temperature of the mold to a predetermined set temperature using a mold temperature controller, etc., assuming actual molding with an injection molding machine. It is generally carried out in a hot state. On the other hand, positioning is rarely performed in a mold clamped state with a regular mold clamping force applied. Therefore, when actual molding is started in an injection molding machine after adjusting the position of the nozzle touch, mold temperature fluctuations due to the influence of the molten resin filled in the mold and compressive deformation of the mold due to mold clamping force may occur. A deviation may occur between the initially positioned nozzle position of the sub-injection cylinder and the position of the sprue bush of the mold.

Taking this into consideration, the sprue bush of the mold is formed with a concave spherical shape, and the nozzle tip of the injection cylinder is formed with a convex spherical shape. The radius of the spherical convex shape at the nozzle tip is configured to be the same as or smaller than the radius of the spherical concave shape of the sprue bush. Therefore, even if the above-mentioned deviation occurs, the nozzle touch state is maintained by maintaining a predetermined nozzle touch force.

However, when the sub-injection device is arranged in a direction perpendicular to the opening/closing direction of the mold, if the nozzle touch state is maintained with the above-mentioned misalignment, the sub-injection A load (hereinafter referred to as an unexpected load) acts in a direction perpendicular to the direction of movement of the injection cylinder. For a combination of a small injection molding machine and a small mold, such unexpected loads are small, and are higher than the allowable values in the specifications of linear motion guides used in sub-movement devices and known linear motion guide mechanisms. It is small or the impact of unexpected loads is small.

On the other hand, in the combination of a large injection molding machine and a large mold, the size of the sub-injection device does not necessarily increase in proportion to the size of the injection device of the injection molding machine, as explained earlier. In some cases, the effects of unexpected loads cannot be ignored. Unexpected loads can cause damage to the sliding of the sub-injection device, such as a decrease in the guiding accuracy of the linear guide or known linear movement guide mechanism used in the sub-transfer device, and a shortened lifespan of sliding members due to uneven wear. This can cause part defects.

If the influence of such an unexpected load acting on the sub-moving device cannot be ignored, it is preferable that the connecting member 224 is provided with at least one sliding permitting portion 227 described above. In the first embodiment, the tip of the cylinder rod 225a of the fluid cylinder 225 constituting the connecting member 224 is connected to the side surface of the fixed mold 36a via the sliding portion 227. Even if the above-mentioned deviation occurs in the nozzle touch state of the sub-injection cylinder 221 of the sub-injection device 220, most of the deviation is caused by the sliding allowance part 227 on the side surface of the fixed mold 36a. This is absorbed by the movement of the tip member 227a of the cylinder rod 225a relative to the fixed member 227b, and the unexpected load acting on the sub-moving device 123 is greatly suppressed.

In the first embodiment, the cylinder rod 225a of the fluid cylinder 225 of the connection member 224 composed of the fluid cylinder 225 and the connection auxiliary member 226 is connected to the side surface of the fixed mold 36a via the sliding portion 227. That is, the embodiment in which the sliding portion 227 is provided on the fixed mold 36a side of the connecting member 224 has been described. However, a configuration may be adopted in which a sliding portion is disposed in the middle of the connecting member 224. Specifically, the cylinder body portion 225b of the fluid cylinder 225 is connected to the connection auxiliary member 226 via a sliding permitting portion having a similar function.

On the other hand, there is a configuration in which the cylinder body portion 225b and the connection auxiliary member 226 are directly fixed, and the connection auxiliary member 226 is connected to the sub-injection cylinder 221 via a sliding permitting portion having a similar function, that is, the sub-injection cylinder 221 of the connection member 224 is A configuration may also be adopted in which a sliding permitting portion 227 is provided on the injection cylinder 221 side. Further, both ends of the connecting member 224 may be connected to the respective connection targets via sliding allowing parts having similar functions.

Further, as described above, in the case where the cylinder rod 225a of the fluid cylinder 225 is connected to the side surface of the fixed mold 36a via the sliding portion 227, the cylinder body portion 225b of the fluid cylinder 225 is connected to the connecting auxiliary member 225. It may be fixed directly to the However, as shown in FIG. 4, the fluid cylinder 225 may be rotatably supported. In the first embodiment, the cylinder body portion of the fluid cylinder 225 is fixed to the connection auxiliary member 226 via the rotating portion 228 (main portion Y in FIG. 2(a)). The rotating portion 228 will be explained with reference to FIG. 4.

In the rotating part 228, a double clevis part 225d formed on the cylinder body part 225b and a single clevis part 226a formed on the connection auxiliary member 226 side are connected by a clevis pin 225e, and the clevis pin 225e is the center of rotation. It supports the rotation of the fluid cylinder 225 and transmits the injection reaction force to the connection auxiliary member 226 in the direction of expansion and contraction of the fluid cylinder 225. In FIG. 4, the rotating portion 228 including each clevis portion is configured so that the clevis pin 225e is arranged horizontally.

The rotating portion 228 is disposed at a different position from the sliding permitting portion 227 of the connecting member 224, so that movement of the connecting member 224 in the sliding permitting portion 227 in the entire circumferential direction perpendicular to the expansion/contraction direction of the fluid cylinder 225 is facilitated. This is a configuration for ease of use. Therefore, in advance or after installing the sub-injection device 220, the direction in which the nozzle 121a of the sub-injection cylinder 221 deviates from the sprue bush 36d on the side surface of the fixed mold 36a is determined, and the fluid cylinder 225 is rotatably supported in this direction. It is preferable to configure the rotating portion 228 including the clevis pin so that the clevis pin is rotated.

Next, a fluid circuit (pneumatic circuit) configured in the fluid cylinder 225 will be described with reference to FIGS. 6 and 7.

As shown in FIG. 6, the rod side chamber of the fluid cylinder 225 is connected to the secondary side No. of the solenoid valve 252 via a conduit in which the pressure reducing valve 251 is arranged. 4 port (A port), and the head side chamber is connected to the secondary side No. 4 of the solenoid valve. 2 port (B port). The solenoid valve 252 is a 3-position closed center type. By adopting a 3-position closed center type in which both solenoids AB of the solenoid valve 252 are not energized and maintained at an intermediate position by spring force, unintentional sliding of the fluid cylinder 225 during a power outage is prevented and safety is ensured. In addition, the air pressure of the head side chamber and the rod side chamber of the fluid cylinder 225 is reliably maintained at the intermediate position of the solenoid valve 252 at the connecting port of the rod side chamber and the head side chamber of the fluid cylinder 225, and the air pressure of the head side chamber and the rod side chamber of the fluid cylinder 225 is Preferably, a pilot check valve is arranged to allow expansion and contraction of the valve.

Then, when solenoid A (left side in FIG. 6) of the solenoid valve 252 is excited, as shown in FIG. 7(a), the primary side No. of the solenoid valve 252 is activated. Air at a predetermined pressure supplied to port 1 (port P) is supplied to the secondary side No. 1 of the valve. It is supplied from port 4 (port A) to the rod side chamber of the fluid cylinder 225 via the pressure reducing valve 251. Since the cylinder rod 225a is connected to the side surface of the fixed mold 36a via the sliding portion 227 (not shown), the cylinder main body 225b moves toward the fixed mold 36a. Along with this movement, guided by the sub-movement device 123, a nozzle touch operation to the side surface of the fixed mold 36a of the sub-injection cylinder 221 (not shown) is started. On the other hand, as the cylinder main body 225b moves toward the fixed mold 36a, air in the head side chamber flows to the primary side No. of the solenoid valve 252. It is discharged from port 3 (EB port).

When the nozzle touch operation of the sub-injection cylinder 221 is started and the nozzle 121a contacts the sprue bushing 36d on the side of the fixed mold 36a, it becomes physically difficult to move the cylinder body 225b toward the fixed mold 36a, so the fluid cylinder The pressure in the rod side chamber of 225 and the connected pipe line increases. When this pressure reaches the set pressure previously set in the pressure reducing valve 251, the same pressure acts as a pilot pressure from the secondary side of the pressure reducing valve 251 to make the pressure reducing valve 251 function, and the pressure in the rod side chamber of the fluid cylinder 225 is is maintained at the set pressure of the pressure reducing valve 251. That is, the pressure of the air maintained in the rod side chamber of the fluid cylinder 225 becomes a nozzle touch force by the pressure reducing valve 251, suppressing the expansion of the fluid cylinder 225 against the injection reaction force, and changing the nozzle touch state to a predetermined nozzle. Keep under touch force.

Although it depends on the structure of the mold, during molding, the sub-injection cylinder of the sub-injection device generally maintains a state in which the nozzle touches the side surface of the fixed mold. However, when stopping the operation of the injection molding machine after molding is completed, when performing maintenance or replacement of the mold, or when moving the sub-injection device from the side of the injection molding machine, move the sub-injection cylinder to the retraction limit position. move it.

In that case, specifically, the excitation of solenoid A of the solenoid valve 252 is stopped, and the solenoid B (on the right side in FIG. 6) is energized. Then, the solenoid valve 252 transits through the intermediate position shown in FIG. 6 to the state shown in FIG. 7(b). Then, air at a predetermined pressure is supplied to the secondary side No. of the same valve. The fluid is supplied from port 2 (port B) to the head side chamber of the fluid cylinder 225, and the cylinder body portion 225b is separated from the fixed mold 36a. Along with this separation, the nozzle 121a of the sub-injection cylinder 221 is guided by the sub-movement device 123 and separated from the sprue bush 36d on the side surface of the fixed mold 36a, and the nozzle touch state is released, and the sub-injection cylinder 221 is Move to the reverse limit position shown in (a). On the other hand, as the cylinder body portion 225b is separated from the fixed mold 36a, air in the rod side chamber flows to the primary side No. of the solenoid valve 252. It is discharged from port 5 (EA port).

If the sub-injection cylinder 221 is configured to be in the backward limit position shown in FIG. Reaching the backward limit can be detected. Even if this is not the case, reaching the retraction limit of the sub injection cylinder 221 can be detected by arranging a proximity switch, a position detection switch, or a limit switch that can detect when the sub injection cylinder 221 reaches the retraction limit in the sub moving device 123. . In either case, after it is detected that the sub-injection cylinder 221 has reached its retraction limit, the excitation of the solenoid B of the solenoid valve 252 is stopped, and the solenoid valve 252 is returned to the intermediate position shown in FIG.

Note that the schematic fluid circuit diagrams shown in FIGS. 6 and 7 include only the configuration necessary for explaining the first embodiment as an example. In reality, the pilot check valve mentioned above, the speed controller (flow control valve) that adjusts the operating speed of the fluid cylinder 225, the pressure of the supplied air, the removal of contaminants and moisture, or the lubrication (lubricator), etc. Various known pneumatic devices to be managed are arranged. Illustrations of these various pneumatic devices are omitted.

Here, unlike the first embodiment, even if the cylinder main body 225b of the fluid cylinder 225 is connected to the fixed mold 36a side and the cylinder rod 225a is connected to the sub-injection cylinder 221 side (connection auxiliary member 226), the fluid The fluid circuit employed in the cylinder 225 is the same as in the first embodiment. That is, the nozzle touch operation of the sub-injection cylinder 221 and the maintenance of the nozzle touch force are performed by supplying fluid at a predetermined pressure to the rod side chamber of the fluid cylinder 225, and the nozzle touch state is released by supplying fluid at a predetermined pressure to the head side chamber. It may be done by supply.

In this way, part or all of the connecting member is configured with a fluid cylinder, and by configuring the fluid circuit of the fluid cylinder in this way, even if a nozzle touch function with a drive source is installed, the sub-injection device cannot be used. The configuration is not complicated, and the nozzle touch operation, which was performed manually in the conventional sub-injection device 120, is performed by a connecting member partially or entirely composed of a fluid cylinder, and the nozzle is touched by a fluid circuit including the fluid cylinder. It is possible to set and maintain the touch force. As with other operations of the sub-injection device, the nozzle touch operation and maintenance of the nozzle touch state of the sub-injection device can be performed using a control device or operation panel (operation pendant) dedicated to the sub-injection device.

Furthermore, it has been explained that the sub-injection device 220 and the simple arrangement of the sub-injection device 220 according to the first embodiment are suitable at the stage of considering the adoption of the sub-injection device or at the stage of prototyping a molded product. However, since the molding trial was performed with the simple arrangement of the sub-injection device 220 as described above, there was no need to arrange the sub-injection device 220 in a special form, and it was possible to continue without any problems with the simple arrangement as described above. If it is confirmed that lamination molding is possible, this arrangement may be made permanent.

Although the first embodiment has been described above as the mode for carrying out the invention, the present invention is not limited to the above embodiment, and the present invention can be implemented without departing from the scope of the claims. Needless to say, this can be implemented in a variety of ways.

For example, although the sliding permitting section 227 has been described with reference to FIG. 3, it may be a sliding permitting section 227' as shown in FIG. 5(a) is a side view of the sliding allowance part 227 corresponding to FIG. 3(a), and FIG. 5(b) is a side view of the sliding allowance part 227 corresponding to FIG. It is a CC arrow view of a).

One of the differences between the sliding allowance part 227 of the first embodiment shown in FIG. 3 and the sliding allowance part 227' shown in FIG. The point is that the fixing member 227b' is not configured to be fixable but is an integral type, and a notch 227c is formed in the opening of the fixing member 227b'. Another point is that the fixed member 227b' is connected to the fixed mold 36a via the heat insulating member 227d.

The notch width of the notch portion 227c is made larger than the outer diameter of the small diameter portion so that the small diameter portion of the tip member 227a can pass through. By configuring the sliding portion 227' in this manner, the structure of the tip member 227a is simplified, and the tip member 227a can be easily assembled into the fixing member 227'. Further, the fixed state between the fluid cylinder 225 and the fixed mold 36a can be released without removing the fixed member 227' from the fixed mold 36a. On the other hand, although not shown, a width across flats part is formed in the small diameter part of the tip member 227a, and the notch width of the cutout part 227c is adjusted to the width across flats so that the width across flats part can pass through. It may be made larger than the width.

Further, by connecting the fixed member 227' to the fixed mold 36a via the heat insulating member 227d, even if the temperature of the fixed mold 36a increases, the heat can be suppressed from being transmitted to the fluid cylinder 225. Such a heat insulating member is placed between the mold and the mold mounting board, and is also employed for the purpose of preventing heat from the mold from being dissipated to the mold mounting board in temperature control of the mold. Therefore, we can easily make various materials of any size that can withstand the tightening force of bolts, such as those made of glass fiber as the base material and using boric acid chlorine binder or heat-resistant epoxy resin as the main material. can be obtained.

By employing such a heat insulating member 227d, the air in the fluid cylinder 225 expands due to the heat of the fixed mold 36a, which may cause malfunction of the nozzle touch operation of the sub-injection cylinder 221 or cause fluctuations in the nozzle touch force. It is possible to suppress the occurrence of Further, it can be expected that adverse effects caused by heat, such as deterioration of packings in the sliding portion between the cylinder rod 225a and the cylinder body portion 225b and deterioration of the sliding lubricant, can be suppressed.

In addition, the embodiment in which the connection member 224 is composed of the fluid cylinder 225 and the connection auxiliary member 226 has been described. With this form, the stroke of the fluid cylinder 225 can be set to +α required for the nozzle touch operation, and the total length of the fluid cylinder can be suppressed. Furthermore, even if it is difficult to arrange the connecting member 224 between the side surface of the fixed mold 36a and the sub-injection cylinder 221 in parallel to the moving direction of the sub-injection cylinder 221, the expansion and contraction direction of the fluid cylinder 225 and the axis of the connecting auxiliary member 226 can be avoided. A structure in which the core is partially eccentric is possible, and there is an advantage that the degree of freedom in the arrangement of the connecting member 224 is improved.

On the other hand, unlike the first embodiment, the fluid cylinder 225 is connected to the fixed mold 36a side and the connection auxiliary member 226 is connected to the sub-injection cylinder 221 side, but it is the opposite, that is, the connection auxiliary member 226 is connected to the fixed mold 36a side. Even if the fluid cylinder 225 is connected to the sub-injection cylinder 221 side on the 36a side, the same effects as described above can be achieved. As explained above, the slide permitting portion 227 and the rotating portion 228 may be arranged at any position in the fluid cylinder 225 or the connection auxiliary member 226, or whether not one but two may be arranged. Depending on the arrangement of the fixed mold 36a and the sub-injection device 220, a suitable combination may be adopted as appropriate. Further, if both the injection molding machine 10 and the sub-injection device 220 are small and the arrangement of the connecting member 224 is permitted, the connecting member 2224 itself may be configured with a fluid cylinder.

Furthermore, the embodiment in which the fluid cylinder 225 of the first embodiment is an air cylinder has been described. Even in an all-electric injection molding machine, compressed air is supplied to the molding machine body as a utility, so there is no problem in using the fluid cylinder 225 as an air cylinder. On the other hand, even in an all-electric injection molding machine, a hydraulic supply device is often installed to drive movable parts such as a mold core. In such a case, the fluid cylinder 225 may be a hydraulic cylinder. Generally, even with a hydraulic supply device, the pressure of hydraulic fluid that can be supplied is higher than the pressure of air that is supplied as a utility. Therefore, the diameter of the fluid cylinder required to generate the same nozzle touch force can be reduced, which has the advantage of improving the degree of freedom in arranging the connecting member 224 as described above.

Additionally, hydraulic oil has very low compressibility with respect to air. Therefore, as shown in FIG. 7A, the state of supply of hydraulic oil to the rod side chamber of the fluid cylinder 225 may be maintained to maintain the nozzle touch state, but the solenoid valve 252 as shown in FIG. It is also possible to maintain the nozzle touch state by blocking the pipes connected to both the rod side chamber and the head side chamber of the fluid cylinder 225 when the nozzle is in an intermediate position (all ports blocked). If the relief valve is placed in the same position as the pressure reducing valve 251 in FIG. This has the advantage that the nozzle touch state can be maintained without continuing the supply of fluid (hydraulic oil).

10 injection molding machine, 20 injection device, 21 injection cylinder, fixed plate, 34 movable plate, 36 mold, 36a fixed mold, 36b movable mold, 36c cavity, 36d sprue bush (side of fixed mold 36a), 122 sub base, 123 Sub-moving device, 129 Nozzle centering mechanism, 220 Sub-injection device, 221 Sub-injection cylinder, 224 Connection member, 225 Fluid cylinder, 225a Cylinder rod, 225b Cylinder main body, 226 Connection auxiliary member, 227/227' Sliding permission part, 227a tip member, 227b/227b' fixed member, 227c notch part, 227d heat insulation member, 228 rotating part, 251 pressure reducing valve, 252 solenoid valve, CL1/CL2 clearance

Claims (2)

A sub-injection device disposed in a direction perpendicular to the opening/closing direction of a mold attached to an injection molding machine, the sub-injection device injecting and filling the mold with molten resin,
a sub-base placed on the foundation and having a sub-injection cylinder placed above;
a sub-moving device that is disposed between the sub-injection cylinder and the sub-base and supports the sub-injection cylinder so as to be movable in a direction perpendicular to the opening/closing direction of the mold;
a connecting member connecting a fixed side surface of the mold and the sub-injection cylinder;
Equipped with
A sub-injection device characterized in that a part or all of the connecting member is composed of a fluid cylinder. The sub-injection device according to claim 1, wherein the connecting member includes at least one sliding portion that allows the fluid cylinder to move by a predetermined amount in a circumferential direction perpendicular to an expansion and contraction direction of the fluid cylinder.

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