Sprue flow regulation and control valve for injection molding

Abstract

The invention provides a sprue flow regulation and control valve for injection molding, and belongs to the technical field of mold molding. The technical problems that in the prior art, the installation size is large, control is not stable, product flaws are easily caused, and damage is easily caused are solved. The sprue flow regulation and control valve for injection molding comprises a valve body, the valve body is provided with a runner arranged along a first axis, the valve body is further provided with a valve element moving hole arranged along a second axis, the inner end of the valve element moving hole is communicated with the runner, and a valve element capable of moving along the second axis to change the width of a runner channel is arranged in the valve element moving hole. The valve element is connected with an actuator capable of driving the valve element to move along the second axis, the actuator comprises a deformation assembly, the size of the deformation assembly can be deformed through the piezoelectric effect, and the deformation assembly can contract and / or expand through electrical stimulation so that the valve element can be moved. The invention has the advantages of compact construction mode, accurate flow control, abundant control modes, long service life, low possibility of leaving traces on products and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of mold molding, relates to an injection molding device, and in particular to a gate flow control valve used for injection molding. Background Art

[0002] The gate flow control valve is a device that controls the flow of molten material leaving the gate to the mold cavity. In the prior art, the valve needle moves back and forth linearly according to the flow of the molten material. The existence and alternating movement of the valve needle increase the disturbance of the molten material flow, causing material accumulation and stagnation, which will lead to a large amount of material waste. For this reason, people have conducted long-term exploration and proposed various solutions.

[0003] As described in EP520345, the oblique valve needle has the defect of pushing the material to the inner surface of the channel, thereby over-compressing the material when it is extruded. This over-compression extrusion effect can cause defects in the final product. In an attempt to solve this problem, people replaced the valve needle with a knife-type valve located at the material outlet gate. This solution is suitable for simultaneously controlling the opening and closing of multiple nozzles arranged side by side, and these injection molding machines are all controlled by a single actuator, as shown in EP1409222. However, if there is only a single nozzle, the use of a knife-type valve will squeeze the material to the periphery of the gate hole, which will cause defects in the injection molded product due to the lower temperature around the gate hole.

[0004] A better solution, as shown in EP1064138, is to use two opposing knife-type valves with their closing point located in the center of the channel, because the higher temperature there can alleviate the defect to a certain extent.

[0005] However, EP1064138 provides two planar knife-type valves operated by a single actuator located at the far edge of the mold, which presents great difficulties in handling the molten material and cannot accurately control the position of the knife-type valves. In addition, the installation process is complicated and the use cost is expensive, because the knife-type valve is close to the outlet of the molten material, that is, close to the mold cavity, and therefore requires a small containment thickness, so it is necessary to use very durable and expensive materials. And, despite these efforts, this solution still leaves traces like small cylindrical protrusions on the injection molded part. Summary of the invention

[0006] The object of the present invention is to provide a gate flow control valve for injection molding in view of the above problems.

[0007] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a gate flow control valve for injection molding, comprising a valve body, the valve body being provided with a flow channel arranged along a first axis, the valve body being also provided with a valve core movable hole arranged along a second axis and the inner end of which is connected to the flow channel, the valve core movable hole being provided with a valve core which can move along the second axis to change the width of the flow channel, the valve core being connected to an actuator which can drive the valve core to move along the second axis, the actuator comprising a deformation component whose volume can be deformed by piezoelectric effect, and the deformation component can be contracted and / or expanded by electrical stimulation to move the valve core.

[0008] The first axis is perpendicular to the second axis, or the first axis intersects the second axis at a point. The deformation component contracts and / or expands through the piezoelectric effect, and through its own deformation, the connected valve core is displaced along the second axis, so that the valve core extends into the flow channel through the valve core active hole to regulate the flow of materials in the flow channel.

[0009] In the above-mentioned gate flow control valve for injection molding, an electric system is also included, and the electric system is used to electrically stimulate the deformable component to cause it to contract and / or expand. The electric system can accurately control the electric stimulation of the deformable component, thereby achieving a fine adjustment of the valve core position, and then accurately controlling the width of the flow channel, thereby improving the control accuracy of the gate flow during the injection molding process.

[0010] In the above-mentioned gate flow control valve for injection molding, a displacement multiplication mechanism capable of increasing the moving distance of the deformation component after deformation is provided between the deformation component and the valve core. The most notable feature of the displacement multiplication mechanism is that it can achieve displacement amplification. After the deformation component is deformed, the displacement multiplication mechanism can amplify its smaller deformation into a larger movement, thereby achieving more stable control of the valve core.

[0011] In the above-mentioned gate flow control valve for injection molding, the displacement multiplication mechanism includes an elastically deformable arched member, the two ends of the arched member are respectively connected to the two ends of the deformation component, and the arched portion of the arched member is connected to the valve core. When the deformation component is deformed, the two ends of the arched member will be driven to produce relative displacement. Since the arched member is elastically deformable, the tiny displacement of the deformation component can be amplified and transmitted to the valve core.

[0012] In the above-mentioned gate flow control valve for injection molding, the deformation component is unidirectionally movable, and the arch and / or valve core are connected with an elastic unit that can be used for reverse movement to reset the valve core. The reset function of the elastic unit enables the valve core position to be quickly adjusted in situations where the valve core position needs to be adjusted frequently.

[0013] In the above-mentioned gate flow control valve for injection molding, the ends of several arched parts are connected by a synchronous connector, and the end of the deformation component is arranged on the synchronous connector. The use of the synchronous connector connects the ends of multiple arched parts together, increases the integrity and stability of the structure, and can maintain the stable operation of the system.

[0014] In the above-mentioned gate flow control valve for injection molding, the deformation component includes a deformation piece that can be deformed in volume through the piezoelectric effect; Alternatively, the deformation component is composed of a plurality of deformable parts which are sequentially connected in series and can be deformed in volume through the piezoelectric effect. The plurality of deformable parts are sequentially connected in series so that the deformation amount can be accumulated, thereby achieving a greater displacement effect.

[0015] In the above-mentioned gate flow control valve for injection molding, the two ends of the deformation component are respectively connected to a plurality of arched parts, and the number of arched parts is ≥2. The arched parts themselves have the ability of elastic deformation. When the deformation component undergoes a slight deformation, the arched parts can amplify the deformation and transfer it to the parts connected thereto. This displacement amplification effect helps to achieve more precise displacement control.

[0016] In the above-mentioned gate flow control valve for injection molding, a clearance hole is provided on the inner wall of the flow channel on the side opposite to the movable hole of the valve core; Alternatively, there are at least two valve core movable holes distributed circumferentially along the second axis, and each valve core movable hole is provided with its own valve core. When there are at least two valve core movable holes distributed circumferentially along the second axis, each valve core can independently control the flow of the flow channel. This design helps to improve the accuracy of flow control, so that different flow requirements can be met more accurately.

[0017] In the above-mentioned gate flow control valve for injection molding, the valve core includes a rod-shaped body, the inner end of which is arranged in the valve core movable hole and can move along the second axis to change the width of the flow channel, and the outer end of which is connected to the deformation component. The rod-shaped body moves along the second axis in the valve core movable hole, and can accurately adjust the width of the flow channel, thereby realizing dynamic control of the flow rate. And because the rod-shaped body is directly connected to the deformation component, the slight change of the deformation component can be quickly converted into the movement of the rod-shaped body, thereby realizing high-sensitivity regulation of the flow rate.

[0018] The following are preferred options, which can be used alone or in combination.

[0019] The gate flow control valve for injection molding preferably includes a power supply system for electrically stimulating the deformable part to cause it to shrink and / or expand.

[0020] Preferably, two or more valve cores are connected to the same actuator.

[0021] Preferably, two or more actuators are included, each actuator being connected to at least one valve core.

[0022] Preferably, the actuator is configured to provide linear motion to the valve spool, but curved motion is also possible.

[0023] Preferably, a displacement multiplication mechanism is provided between the deformation component and the valve core, and the displacement multiplication mechanism may include a lever, a hinge, and the like.

[0024] In one variant, the deformation assembly includes a plurality of deformation members arranged in series, such as a linear arrangement or a curved / spiral arrangement, to save space on the mold. Therefore, the total displacement applied to the valve core is the sum of the individual deformations of each deformation member.

[0025] In a variant, the valve core is directly connected to the deformation member so as to achieve the same displacement corresponding to the displacement generated by the deformation member.

[0026] In a variant, the displacement exerted on the valve core by the deformation component is in one direction only, and preferably, in the opposite direction, the valve core is pushed back by an elastic unit.

[0027] In a variant, the displacements exerted on the valve element by the deformation assembly are in two opposite directions.

[0028] In a variant, the valve core is installed in the valve core movable hole.

[0029] In a variant, the valve core is in the shape of a needle, for example straight. In particular, the gate element has a free end and an opposite end connected to the actuator.

[0030] The actuator is preferably mounted in the active cavity of the plate body.

[0031] In one variation, the angle between the axis of the sliding direction of the valve core and the axis of the dimensional change direction of the deformation component is perpendicular.

[0032] In one variation, the same actuator is connected to two or more valve spools to move them simultaneously.

[0033] Compared with the existing technology, the gate flow control valve for injection molding has the following advantages: 1. The present invention can be constructed in a very compact manner and can be arranged near the gate without the need for an additional external actuator. This makes the device more advantageous in space utilization and can better adapt to the complex structure of the injection mold, especially when space is limited, the compact structure can reduce interference with the mold layout.

[0034] 2. The valve core motion control is flexible and diverse, and the valve core can be controlled in various ways through the electronic control unit. This allows the advantages of software programming to be used to accurately control the valve core's movement speed, movement time, movement stroke and other parameters according to different injection molding process requirements, thereby better controlling the flow of molten materials.

[0035] 3. The force is concentrated, which helps to more effectively throttle the channel when controlling the flow of molten material, accurately control the flow of material, avoid product defects, and meet the molding needs of injection molding products of different shapes, sizes and quality requirements.

[0036] 4. Simple mechanical structure, low maintenance cost and long service life. The mechanical structure of the present invention is simple, which means that the cost can be reduced during the manufacturing process, and the probability of failure during use is relatively low. It can also ensure that it can still work normally in a relatively harsh environment, reducing the possibility of equipment failure due to environmental factors. It has a long service life and can work stably in the long-term injection molding production process.

[0037] 5. Using materials with piezoelectric effect to shrink and / or expand them through electrical stimulation provides a convenient input method for controlling the device.

[0038] 6. Two or more valve cores can be connected to the same actuator, or the same actuator can control two or more valve cores. This combination can be flexibly configured according to the actual injection molding requirements to achieve more complex control strategies.

[0039] 7. The actuator can make the valve core move in a straight line or in a curve, and a displacement transmission device (such as a lever, hinge, etc.) can be inserted between the actuator and the valve core, which increases the diversity of movement modes and can better adapt to the requirements of different mold structures and injection molding processes.

[0040] 8. The displacement control of the deformation component in different directions, such as unidirectional displacement, bidirectional displacement, etc., can be realized, and the valve core has various forms such as valve needle shape, which further improves the flexibility and adaptability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram provided by the present invention.

[0042] Figure 2 The present invention provides Figure 1 Enlarge the structural diagram at point A.

[0043] Figure 3 It is a schematic diagram of the structure of the actuator provided by the present invention.

[0044] Figure 4It is a structural schematic diagram of embodiment 2 provided by the present invention.

[0045] Figure 5 It is a schematic diagram of the structure of the actuator of Example 2 provided by the present invention.

[0046] In the figure, the valve body 1, the first axis 11, the second axis 12, the flow channel 13, the valve core movable hole 14, the give way hole 141, the plate body 15, the movable cavity 16, the valve core 2, the rod-shaped body 21, the actuator 3, the deformation component 31, the deformation member 311, the displacement multiplication mechanism 32, the arch member 33, and the synchronous connecting member 35. DETAILED DESCRIPTION

[0047] Embodiment 1 like Figures 1 to 3 As shown, a gate flow control valve for injection molding includes a valve body 1, a flow channel 13 arranged along a first axis 11 is provided on the valve body 1, and a valve core movable hole 14 is also provided on the valve body 1 along a second axis 12 and the inner end of which is connected to the flow channel 13. A valve core 2 capable of moving along the second axis 12 to change the width of the flow channel 13 is provided in the valve core movable hole 14. The valve core 2 is connected to an actuator 3 capable of driving the valve core 2 to move along the second axis 12. The actuator 3 includes a deformation component 31 whose volume can be deformed by piezoelectric effect, and the deformation component 31 can be contracted and / or expanded by electrical stimulation to move the valve core 2.

[0048] In this embodiment, the same parts in the figures are represented by the same numbers, and in order not to crowd the drawings, sometimes only some numbers are reported. Above the runner 13 is an injector, which is installed in the plate body 15 and connected to the plate body 15. The injector includes an innermost hollow body, the center of which is provided with an axial cavity extending longitudinally along the first axis 11, and unlike other known injectors, there is no valve needle arranged parallel to the first axis 11 in the axial cavity. The first axis 11 is preferably also the polar symmetry axis of the injector. The end of the injector is inserted into a gate insert of the plate body 15 having a hole, and the hole is connected to the runner 13, and the molten material flows into the runner 13 from the axial cavity. In general, the injector is prior art, and its structure is known and does not need to be described in detail.

[0049] In this embodiment, the flow channel 13 is arranged along the first axis 11, and the valve core 2 moves along the second axis 12. When one end of the valve core 2 moves to the intersection of the first axis 11 and the second axis 12, that is, the valve core 2 extends into the flow channel 13, it can hinder the flow of material in the flow channel 13, thereby achieving the effect of controlling and regulating the flow rate of the injection molding material.

[0050] More specifically, it also includes an electric system, which is used to electrically stimulate the deformable component 31 to cause it to contract and / or expand.

[0051] More specifically, a displacement multiplier mechanism 32 is provided between the deformation component 31 and the valve core 2 to increase the moving distance of the deformation component 31 after deformation.

[0052] More specifically, the displacement multiplication mechanism 32 includes an elastically deformable arched member 33 , two ends of the arched member 33 are respectively connected to two ends of the deformation component 31 , and a raised portion of the arched member 33 is connected to the valve core 2 .

[0053] More specifically, the deformation component 31 can move in one direction, and the arch member 33 is connected with an elastic unit that can be used for reverse movement to reset it.

[0054] More specifically, the ends of the plurality of arch members 33 are connected via a synchronous connecting member 35 , and the end of the deformation assembly 31 is disposed on the synchronous connecting member 35 .

[0055] More specifically, two ends of the deformation component 31 are connected to two arched members 33 respectively.

[0056] In this embodiment, two ends of the deformation component 31 are respectively connected to two arched members 33 through synchronous connecting members 35 to form an integrated bridge structure.

[0057] By supplying voltage to the deformation component 31, it can be extended or shortened. This dimensional change acts on the bottom of the arch 33 and is converted into a displacement of the valve core 2 along the second axis 12.

[0058] In this embodiment, the angle between the axis of the deformation component 31 in the deformation direction and the second axis 12 is a right angle, and may also be an acute angle or an obtuse angle.

[0059] More specifically, a clearance hole 141 is provided on the inner wall of the flow channel 13 on the side opposite to the valve core movable hole 14; The inner end of the valve core 2 is located in the valve core movable hole 14 , and the outer end is located in the movable cavity 16 of the plate body 15 . The actuator 3 is also disposed in the movable cavity 16 .

[0060] In this embodiment, the outer end of the valve core 2 is a free end, and is connected to the actuator 3 at the opposite inner end, and the clearance hole 141 and the outer free end of the valve core 2 have complementary shapes.

[0061] More specifically, the valve core 2 includes a rod-shaped body 21 , the inner end of which is disposed in the valve core movable hole 14 and can move along the second axis 12 to change the width of the flow channel 13 , and the outer end of the rod-shaped body 21 is connected to the deformation component 31 .

[0062] The working principle of this embodiment is to input an electrical signal to the deformation component 31 of the actuator 3 to make it expand and contract, and guide the arch member 33 to deform synchronously through the synchronous connecting member 35 bridging the two ends of the deformation component 31. When the arch member 33 is deformed, it will drive the valve core 2 to move.

[0063] Then the valve core 2 moves back and forth along the second axis 12, and the free end of the rod-shaped body 21 will extend into or away from the flow channel 13 along the second axis 12, which causes the free end of the rod-shaped body 21 in the flow channel 13 to protrude more or less. The degree of protrusion determines the size of the flow portion of the flow channel 13, that is, determines the degree of closure of the flow channel 13, thereby achieving control of the flow rate of the material in the flow channel 13.

[0064] Embodiment 2 The content of this embodiment is basically the same as that of the first embodiment, except that Figure 4 and 5 As shown, there are two valve core movable holes 14 distributed circumferentially along the second axis 12 , and each valve core movable hole 14 is provided with its own valve core 2 .

[0065] The deformation assembly 31 includes a plurality of deformation members 311 which are sequentially connected in series and are volume-deformable through the piezoelectric effect.

[0066] In this embodiment, the deformation component 31 includes multiple deformation members 311 connected in series, that is, the deformation amount of the deformation component 31 is the sum of the deformation amounts of each deformation member 311, and a separate electrical signal control is set for each deformation member 311, which has the effect of improving the richness of the control method.

[0067] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0068] Although the terms valve body, first axis, second axis, flow channel, valve core active hole, clearance hole, plate body, active cavity, valve core, rod-shaped body, actuator, deformation assembly, deformation member, displacement multiplication mechanism, arch member, synchronous connection member, etc. are used more frequently in this article, the possibility of using other terms is not excluded. The use of these terms is only for more convenient description and explanation of the essence of the present invention. It is contrary to the spirit of the present invention to interpret them as any additional limitation.

Claims

1. A gate flow control valve for injection molding, comprising a valve body (1), wherein the valve body (1) is provided with a flow channel (13) arranged along a first axis (11), and the valve body (1) is further provided with a valve core movable hole (14) arranged along a second axis (12) and the inner end of which is connected to the flow channel (13), wherein the valve core movable hole (14) is provided with a valve core (2) capable of moving along the second axis (12) to change the width of the flow channel (13), wherein the valve core movable hole (14) is provided with a valve core (2) capable of moving along the second axis (12) to change the width of the flow channel (13), characterized in that: The valve core (2) is connected to an actuator (3) capable of driving the valve core (2) to move along a second axis (12); the actuator (3) comprises a deformation component (31) whose volume can be deformed by a piezoelectric effect, and the deformation component (31) can be contracted and / or expanded by electrical stimulation, thereby moving the valve core (2).

2. The gate flow control valve for injection molding according to claim 1, characterized in that: It also includes an electric system, which is used to electrically stimulate the deformable component (31) to cause it to contract and / or expand.

3. The gate flow control valve for injection molding according to claim 1, characterized in that: A displacement multiplication mechanism (32) capable of increasing the moving distance of the deformation component (31) after deformation is provided between the deformation component (31) and the valve core (2).

4. The gate flow control valve for injection molding according to claim 3, characterized in that: The displacement multiplication mechanism (32) comprises an elastically deformable arched member (33), two ends of the arched member (33) are respectively connected to two ends of the deformation component (31), and the arched portion of the arched member (33) is connected to the valve core (2).

5. The gate flow control valve for injection molding according to claim 4, characterized in that: The deformation component (31) is unidirectionally movable, and the arched member (33) and / or the valve core (2) are connected to an elastic unit that can be used to move in the opposite direction to reset the valve core.

6. The gate flow control valve for injection molding according to claim 4, characterized in that: The ends of the plurality of arched members (33) are connected via a synchronous connecting member (35), and the end of the deformation component (31) is arranged on the synchronous connecting member (35).

7. The gate flow control valve for injection molding according to claim 4, 5 or 6, characterized in that: The deformable component (31) comprises a deformable part (311) whose volume can be deformed through the piezoelectric effect; Alternatively, the deformation component (31) comprises a plurality of deformation members (311) which are sequentially distributed in series and are volume-deformable through the piezoelectric effect.

8. The gate flow control valve for injection molding according to claim 7, characterized in that: Both ends of the deformation component (31) are respectively connected to a plurality of arched parts (33), and the number of the arched parts (33) is ≥2.

9. The gate flow control valve for injection molding according to any one of claims 1 to 6, characterized in that: A clearance hole (141) is provided on the inner wall of the flow channel (13) on the side opposite to the valve core movable hole (14); Alternatively, there are at least two valve core movable holes (14) distributed circumferentially along the second axis (12), and each valve core movable hole (14) is provided with its own valve core (2).

10. The gate flow control valve for injection molding according to any one of claims 1 to 6, characterized in that: The valve core (2) comprises a rod-shaped body (21), the inner end of the rod-shaped body (21) being arranged in the valve core movable hole (14) and being movable along the second axis (12) to change the width of the flow channel (13), and the outer end of the rod-shaped body (21) being connected to the deformation component (31).

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