Gas needle-shaped check valve

Abstract

The utility model relates to a gas needle-shaped check valve which comprises a needle cylinder, a valve body, a valve rod and a valve body. The needle cylinder is provided with an air inlet and an air outlet which are oppositely arranged; the needle core comprises a needle rod and a pier head connected with the needle rod, the needle rod is arranged in the needle cylinder in a sliding mode, and the diameter of the end, close to the needle rod, of the pier head is larger than that of the air outlet; the baffle is fixedly mounted on the needle rod, and a ventilation opening is formed in the baffle; and the spring is elastically connected between the needle core and the needle cylinder. Air is injected into the needle cylinder, the air can push the baffle to slide in the direction close to the air outlet, the pier head can open the air outlet, air enters the cavity of the workpiece after passing through the ventilation opening and the air outlet, at the moment, the spring is in an elastic deformation state, after air injection, the spring resets to drive the needle core to move reversely, and therefore the pier head can block the air outlet. Gas in the cavity of the workpiece is prevented from overflowing, sufficient gas can provide supporting force for the cavity wall, cavity wall shrinkage caused by residual internal stress of the workpiece is avoided, the problem of sink marks on the surface of the workpiece is solved and eliminated, and the machining quality of the workpiece is guaranteed.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of injection molding, in particular, to a gas needle check valve. BACKGROUND

[0002] A mold can be used for injection molding of a product, which includes a movable mold and a fixed mold (or a male mold and a female mold), both of which can be separated and combined. When separated, the product is taken out, and when combined, the blank is injected into the mold cavity to be shaped. In the related art, the residual internal stress of a product with a large wall thickness during injection molding easily causes the cavity wall to shrink, and there is currently a lack of a device for inflating the cavity of the product to avoid the shrinkage of the cavity wall and ensure the processing quality of the product. SUMMARY

[0003] In order to overcome the problem that the residual internal stress of a product with a large wall thickness during injection molding easily causes the cavity wall to shrink and affects the processing quality of the product, the utility model provides a gas needle check valve.

[0004] In order to achieve the above-mentioned purpose, the present disclosure provides a gas needle check valve, which comprises:

[0005] A needle cylinder is provided with an air inlet and an air outlet arranged oppositely;

[0006] A needle core comprises a needle rod and a head connected with the needle rod, the needle rod is slidably arranged in the needle cylinder, and the diameter of one end of the head close to the needle rod is greater than the diameter of the air outlet;

[0007] A baffle is fixedly installed on the needle rod, and the baffle is provided with a ventilation opening; and

[0008] A spring is elastically connected between the needle core and the needle cylinder.

[0009] Optionally, the outer diameter of the needle cylinder comprises a first outer diameter, a transition outer diameter and a second outer diameter, the outer periphery of the air outlet corresponds to the first outer diameter, the outer periphery of the air inlet corresponds to the second outer diameter, the transition outer diameter corresponds to the needle cylinder connected with the needle cylinder corresponding to the first outer diameter and the second outer diameter respectively, and the size of the first outer diameter is smaller than the size of the second outer diameter.

[0010] Optionally, the inside of the needle cylinder comprises a limiting cylinder cavity and a sliding cylinder cavity in communication with the limiting cylinder cavity, the diameter of the limiting cylinder cavity is the same as the diameter of the air outlet, the air inlet is formed at one end of the sliding cylinder cavity away from the limiting cylinder cavity, the air outlet is formed at one end of the limiting cylinder cavity away from the sliding cylinder cavity, and the baffle is slidably arranged in the sliding cylinder cavity.

[0011] Optionally, the diameter of the limiting cylinder cavity is 0.02mm-0.07mm larger than the diameter of the needle rod.

[0012] Optionally, the baffle is a circular plate, and the vent is a circular hole formed in the circular plate.

[0013] Optionally, the vent is arranged at the edge of the baffle and is configured in the form of a notch.

[0014] Optionally, the cross section of the baffle is a regular polygon, and a gap between the regular polygon and the cavity wall of the sliding cylinder cavity is the vent.

[0015] Optionally, the spring is sleeved on the outer periphery of the needle rod and is elastically connected with the limiting cylinder cavity and the baffle, respectively.

[0016] The technical scheme provided by the embodiments of the present disclosure can include the following beneficial effects:

[0017] By injecting gas into the needle cylinder through the gas inlet, the gas can push the baffle to slide towards the direction close to the gas outlet, so that the needle rod can drive the plug to move, thereby enabling the plug to open the gas outlet. After the gas passes through the vent and the gas outlet, it enters the cavity of the product. At this time, the spring is in an elastic deformation state. After the gas injection is completed, the spring returns to its original position to drive the needle core to move in the opposite direction. Since the diameter of the end of the plug close to the needle rod is greater than the diameter of the gas outlet, the plug can block the gas outlet to prevent the gas in the cavity of the product from overflowing. Sufficient gas can provide support to the cavity wall to prevent the cavity wall from shrinking due to the residual internal stress of the product, thereby solving and eliminating the shrinkage mark problem on the surface of the product and ensuring the processing quality of the product. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a cross-sectional view of a gas needle check valve according to an exemplary embodiment of the present disclosure.

[0019] 100, needle cylinder; 110, gas inlet; 120, gas outlet; 130, limiting cylinder cavity; 200, needle core; 210, needle rod; 220, plug; 300, spring; 400, baffle. DETAILED DESCRIPTION

[0020] The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0021] In the present disclosure, the orientation words such as "upper", "lower", "left", "right" are used for the convenience of description of the direction of the drawing according to the corresponding drawing, and "inner", "outer" are defined according to the contour of the corresponding part itself. The terms such as "first", "second" used in the present disclosure are used to distinguish one element from another element, and do not have sequentiality and importance. In addition, when the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements, unless otherwise indicated.

[0022] Referring to Figure 1 The embodiment of the present disclosure provides a gas needle check valve, which comprises a needle cylinder 100, a needle core 200, a baffle 400 and a spring 300. The needle cylinder 100 is provided with an air inlet 110 and an air outlet 120 arranged oppositely. The needle core 200 comprises a needle rod 210 and a dome head 220 connected with the needle rod 210, the needle rod 210 is slidably arranged in the needle cylinder 100, and the diameter of the end of the dome head 220 close to the needle rod 210 is greater than the diameter of the air outlet 120. The baffle 400 is fixedly installed on the needle rod 210, and the baffle 400 is provided with a ventilation port. The spring 300 is elastically connected between the needle core 200 and the needle cylinder 100. By arranging the baffle 400, the contact area of the needle rod 210 with the gas can be increased, so that the gas can quickly push the needle rod 210 to slide away from the air inlet 110, and the dome head 220 can open the air outlet 120 of the needle cylinder 100. The needle rod 210 can be hollow, and the dome head 220 can block the hole of the needle rod 210, so that the plastic can be prevented from entering the needle rod 210 during the processing of the product, and the use of plastic is more saved. The gas flowing out of the air outlet 120 can push the dome head 220 to move, and the dome head 220 can block the airflow from penetrating the product. The end of the dome head 220 close to the needle cylinder 100 is circular, and the airflow acting on the circular shape can make the gas flow uniformly forward, thereby ensuring the filling effect of the gas.

[0023] It can be understood that the gas is injected into the needle cylinder 100 through the air inlet 110, the gas can push the baffle 400 to slide towards the air outlet 120, so that the needle rod 210 can drive the dome head 220 to move, thereby opening the air outlet 120, and the wind enters the cavity of the product through the ventilation port and the air outlet 120. At this time, the spring 300 is in an elastic deformation state, and after the injection of the gas is completed, the spring 300 is reset to drive the needle core 200 to move reversely. Since the diameter of the end of the dome head 220 close to the needle rod 210 is greater than the diameter of the air outlet 120, the dome head 220 can block the air outlet 120, thereby preventing the gas in the cavity of the product from flowing back to the needle cylinder 100 through the air outlet 120. Sufficient gas can provide support for the cavity wall, thereby avoiding the shrinkage of the cavity wall caused by the residual internal stress of the product, solving and eliminating the problem of surface shrinkage of the product, and ensuring the processing quality of the product.

[0024] The gas needle check valve can be installed in the cavity of the mold. In the embodiment, the gas needle check valve can be installed on the movable mold. The gas needle check valve can extend into the interior of the product and enter the narrow cavity of the product, so that the filled gas can quickly enter the cavity. Of course, in other embodiments, the gas needle check valve is not connected with the movable mold, but is connected with the cavity of the mold through a power member. After the movable mold is opened, the power member is started to drive the gas needle check valve to separate from the product.

[0025] In an embodiment, referring to Figure 1 , the outer diameter of the needle cylinder 100 includes a first outer diameter, a transition outer diameter, and a second outer diameter. The outer periphery of the gas outlet 120 corresponds to the first outer diameter, and the outer periphery of the gas inlet 110 corresponds to the second outer diameter. The transition outer diameter corresponds to the part of the needle cylinder 100 that is connected with the parts of the needle cylinder 100 corresponding to the first outer diameter and the second outer diameter, respectively. The size of the first outer diameter is smaller than the size of the second outer diameter, that is, the needle cylinder 100 is configured as a stepped cylinder, which facilitates the pulling out of the needle cylinder 100 after the product is formed. The diameter of the gas outlet 120 is relatively small, and a smaller punch head 220 can be used to block the gas outlet 120, saving the use of material for the punch head 220 and ensuring that the punch head 220 can fit the cavity of a small product.

[0026] In an embodiment, referring to Figure 1 , the interior of the needle cylinder 100 includes a limiting cylinder cavity 130 and a sliding cylinder cavity in communication with the limiting cylinder cavity 130. The diameter of the limiting cylinder cavity 130 is the same as the diameter of the gas outlet 120, which facilitates the rapid processing of the limiting cylinder cavity 130 and the gas outlet 120. The gas inlet 110 is formed at the end of the sliding cylinder cavity away from the limiting cylinder cavity 130, and the gas outlet 120 is formed at the end of the limiting cylinder cavity 130 away from the sliding cylinder cavity. The baffle 400 slides in the sliding cylinder cavity. After the baffle 400 slides to the junction of the limiting cylinder cavity 130 and the sliding cylinder cavity, the end of the limiting cylinder cavity 130 will prevent the baffle 400 from continuing to advance, avoiding the needle rod 210 penetrating the cavity of the product due to the excessive length of the needle rod 210, and ensuring the integrity of the structure of the product.

[0027] In an embodiment, referring to Figure 1 , the diameter of the limiting cylinder cavity 130 is 0.02-0.07 mm larger than the diameter of the needle rod 210. For example, the diameter of the limiting cylinder cavity 130 is 0.02 mm, 0.04 mm, 0.05 mm, 0.06 mm, or 0.07 mm larger than the diameter of the needle rod 210. Therefore, the gap between the limiting cylinder cavity 130 and the outer periphery of the needle rod 210 is small, which ensures that the needle rod 210 does not shake significantly in the radial direction of the limiting cylinder cavity 130 during movement.

[0028] In an embodiment, the baffle plate 400 is a circular plate, the ventilation hole is a circular hole, and the ventilation hole is arranged on the circular plate. The air can enter the gap between the outer periphery of the iron rod and the limiting cylinder cavity 130 through the circular hole.

[0029] In an embodiment, the ventilation hole is arranged at the edge of the baffle plate 400 and is configured as a notch. The air can enter the gap between the outer periphery of the iron rod and the limiting cylinder cavity 130 through the circular hole.

[0030] In an embodiment, the cross section of the baffle plate 400 is a regular polygon. The gap between the regular polygon and the cavity wall of the sliding cylinder cavity is a ventilation hole. The air can enter the gap between the outer periphery of the iron rod and the limiting cylinder cavity 130 through the circular hole.

[0031] In an embodiment, referring to Figure 1 The spring 300 is sleeved on the outer periphery of the needle rod 210 and is elastically connected with the limiting cylinder cavity 130 and the baffle plate 400, respectively. The spring 300 occupies less space in the needle cylinder 100. The spring 300 is detachably connected with the needle cylinder 100 and the baffle plate 400 through the bolts. The maintenance and repair of the gas needle check valve are facilitated.

[0032] The present application is described by way of examples. Those skilled in the art know that various changes or equivalent replacements can be made to the features and examples without departing from the spirit and scope of the present application. In addition, the features and examples can be modified to adapt to specific conditions and materials under the guidance of the present application without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the specific examples disclosed herein. All examples falling within the scope of the claims of the present application are within the protection scope of the present application.

Claims

1. A gas needle check valve characterized by, The utility model relates to a needle cylinder (100) is provided with opposite gas inlet (110) and gas outlet (120), needle core (200) including needle bar (210) and with needle bar (210) connection head (220), needle bar (210) slide in needle cylinder (100) inside, the diameter of the end of head (220) near needle bar (210) is greater than the diameter of gas outlet (120), baffle (400) fixed mounting on needle bar (210), baffle (400) is equipped with ventilation opening and spring (300) is elastically connected between needle core (200) and needle cylinder (100). The outer diameter of the needle cylinder (100) includes a first outer diameter, a transition outer diameter, and a second outer diameter. The outer periphery of the gas outlet (120) corresponds to the first outer diameter, the outer periphery of the gas inlet (110) corresponds to the second outer diameter, and the transition outer diameter corresponds to the needle cylinder (100) connected with the needle cylinder (100) corresponding to the first outer diameter and the second outer diameter, respectively. The size of the first outer diameter is smaller than the size of the second outer diameter. The inside of the needle cylinder (100) includes a limiting cylinder cavity (130) and a sliding cylinder cavity in communication with the limiting cylinder cavity (130). The diameter of the limiting cylinder cavity (130) is the same as the diameter of the gas outlet (120). The gas inlet (110) is formed at one end of the sliding cylinder cavity away from the limiting cylinder cavity (130). The gas outlet (120) is formed at one end of the limiting cylinder cavity (130) away from the sliding cylinder cavity. The baffle (400) is slidably arranged in the sliding cylinder cavity. The diameter of the limiting cylinder cavity (130) is 0.02mm to 0.07mm larger than the diameter of the needle bar (210). The baffle (400) is a circular plate, and the ventilation opening is a circular hole formed on the circular plate.

2. The gas check valve according to claim 1, characterized by The ventilation opening is located at the edge of the baffle and is configured as a notch.

3. The gas check valve according to claim 1, wherein The cross section of the baffle (400) is a regular polygon. The regular polygon and the cavity wall of the sliding cylinder cavity have a gap, and the gap is the ventilation opening.

4. The gas check valve according to claim 3, wherein The spring (300) is sleeved on the outer periphery of the needle bar (210) and is elastically connected with the limiting cylinder cavity (130) and the baffle (400), respectively.

5. The gas check valve according to claim 3, wherein ​ 6. The gas check valve according to claim 3, wherein ​ 7. The gas check valve according to claim 3, wherein ​ 8. The gas check valve according to claim 3, wherein ​

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