Valve needle and hot runner system
By designing a valve needle with specific diameter segments and transition parts, the problem of residual plastic in the shadow area on the back of the valve needle is solved, avoiding product quality problems and reduced production efficiency, and achieving more stable product output.
Patent Information
- Application Number
- CN202421384763.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-18
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-06-18
AI Technical Summary
In traditional needle valve hot runner system, plastic is easily left in the shadow area on the back of the valve needle, causing the plastic to be heated and decomposed and carbonized, causing quality problems such as yellowing and blacking of the product, and may lead to product color mixing.
A valve needle is designed, and its valve stem is composed of three sections of coaxial connection, the diameter of the second section is smaller than that of the third section. The transition piece is used for smooth connection, ensuring that the plastic is more easily washed away during the flow process and avoiding residue.
It effectively avoids the long-term residue of plastic in the shadow area on the back of the valve needle, prevents heat decomposition and carbonization, improves product quality and appearance, reduces production costs and improves production efficiency.
Smart Images
Figure CN222628481U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of plastic injection molding, in particular to a valve needle and a hot runner system. Background Art
[0002] In the traditional needle valve hot runner system injection molding process, the molten plastic flows through the diverter channel and then flows along the valve needle to the nozzle. However, in this process, there is a problem with the back shadow area of the valve needle: some plastic will remain in the back shadow area of the valve needle and stay there for a long time. This residual plastic is easily affected by high temperature and high pressure, causing it to decompose and carbonize under heat, resulting in quality problems such as yellowing and blackening of the final product. In addition, when changing plastics of different colors, the plastic remaining in the back shadow area will also mix with the new plastic, resulting in mixed colors of the product.
[0003] This problem of residual plastic in the shadow area on the back of the valve needle has an adverse effect on the quality and appearance of plastic products, leading to increased production costs, reduced production efficiency, unstable product quality and other problems. Utility Model Content
[0004] According to an embodiment of the utility model, a valve needle is provided, comprising a valve needle hanging platform, a valve stem and a valve needle head, wherein the valve stem comprises:
[0005] The first section, one end of which is connected to the tail of the valve stem;
[0006] The second segment, one end of the second segment is connected to the other end of the first segment;
[0007] A third section, one end of the third section is connected to the other end of the second section, and the other end of the third section is connected to the valve needle head;
[0008] The first section, the second section and the third section are coaxially connected in sequence.
[0009] Furthermore, the diameter of the first section is larger than the diameter of the third section, and the diameter of the second section is smaller than the diameter of the third section.
[0010] Further, it also includes: a pair of transition pieces;
[0011] A transition piece is provided at the connection between the first section and the second section, for smoothly connecting the first section and the second section;
[0012] Another transition piece is arranged at the connection between the second section and the third section, and is used for smoothly connecting the second section and the third section.
[0013] Furthermore, the cross section of the second section is circular.
[0014] According to another embodiment of the utility model, a hot runner system is provided, comprising: a valve needle, a flow divider, a flow divider plate and a nozzle;
[0015] The diverter channel is opened inside the diverter plate;
[0016] The runner opening of the branch channel is connected to the nozzle, and the molten plastic is divided through the branch channel and flows to the nozzle;
[0017] The valve needle is arranged at the flow channel opening of the branch flow channel.
[0018] According to the valve needle and hot runner system of the embodiment of the utility model, the molten plastic will not remain in the shadow area on the back of the valve needle for a long time, thus avoiding the residual plastic staying in the shadow area on the back of the valve needle for a long time and being affected by high temperature and high pressure, causing it to decompose and carbonize due to heat, resulting in quality problems such as yellowing and blackening of the final product.
[0019] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the technology as claimed. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 is a schematic diagram of a valve needle according to an embodiment of the utility model;
[0021] Figure 2 FIG. 4 is a schematic diagram of a hot runner system according to another embodiment of the present invention. DETAILED DESCRIPTION
[0022] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings to further illustrate the present invention.
[0023] First, combine Figure 1 The valve needle according to the embodiment of the utility model is described, and its application scenarios are very wide.
[0024] like Figure 1 As shown, the valve needle of the embodiment of the utility model comprises a valve needle hanging platform 1 , a valve stem 2 and a valve needle head 3 , and the valve stem 2 comprises: a first section 21 , a second section 22 and a third section 23 .
[0025] Specifically, Figure 1 As shown, one end of the first section 21 is connected to the valve needle hanging platform 1; one end of the second section 22 is connected to the other end of the first section 21; one end of the third section 23 is connected to the other end of the second section 22, and the other end of the third section 23 is connected to the valve needle head 3; the first section 21, the second section 22 and the third section 23 are coaxially connected in sequence.
[0026] Furthermore, the diameter of the first section 21 is larger than the diameter of the third section 23, and the diameter of the second section 22 is smaller than the diameter of the third section 23. When the valve needle in this embodiment is in use, the diameter of the second section 22 is small. When the molten plastic flows through the second section 22, the plastic hidden in the back shadow area of the second section 22 will be more easily washed away by the flowing plastic, avoiding the residual plastic from being affected by high temperature and high pressure, causing it to decompose and carbonize under heat, causing the final product to have quality problems such as yellowing and blackening. At the same time, such a structure can also solve the problem that when changing plastics of different colors, the plastic remaining in the back shadow area will also mix with the new plastic, causing the product to mix colors.
[0027] Further, if Figure 1 As shown, it also includes: a pair of transition pieces 4; one transition piece 4 is provided at the connection between the first section 21 and the second section 22, for smoothly connecting the first section 21 and the second section 22; the other transition piece 4 is provided at the connection between the second section 22 and the third section 23, for smoothly connecting the second section 22 and the third section 23. The transition piece 4 in this embodiment is truncated cone-shaped, and when the valve needle in this embodiment is pressed down for use, the truncated cone-shaped transition piece 4 connecting the first section 21 and the second section 22 will squeeze the plastic to the nozzle.
[0028] Furthermore, the cross section of the second section 22 is circular. In this embodiment, the second section 22 is preferably a cylinder with a circular cross section because when the molten plastic passes through the second section 22, the plastic is easier to flow through the cylinder and is less likely to remain in the shadow area on the back thereof.
[0029] like Figure 2 As shown, according to another embodiment of the utility model, a hot runner system is provided, comprising: a valve needle, a diverter plate 5, a diverter channel 6 and a nozzle 7; the diverter channel 6 is opened inside the diverter plate 5; the flow channel opening of the diverter channel 6 is connected to the nozzle 7, and the molten plastic is diverted through the diverter channel 6 and flows to the nozzle 7; the second section 22 of the valve needle is located at the flow channel opening of the diverter channel 6, which can effectively reduce the obstruction of the valve needle to the molten plastic, thereby achieving the flushing away of the residual plastic in the shadow area on the back of the valve needle.
[0030] When using the valve needle of this embodiment, when the valve needle is in an open state, the second section 22 is at the flow channel opening of the branch channel 6, and the molten plastic will flow into the nozzle 7 along the second section 22 and the third section 23, and finally be injected into the mold cavity from the nozzle 7 for injection molding; when the valve needle is in a closed state, the first section 21 will move downward to block the flow channel opening of the branch channel 6, and the plastic cannot flow to the nozzle 7, thereby achieving control over whether the molten plastic can enter the external mold cavity through the nozzle 7.
[0031] Above, refer to Figure 1 , 2The valve needle and hot runner system according to the embodiment of the utility model are described. The molten plastic will not remain in the shadow area on the back of the valve needle for a long time, thus avoiding the residual plastic staying in the shadow area on the back of the valve needle for a long time and being affected by high temperature and high pressure, causing it to decompose and carbonize due to heat, resulting in quality problems such as yellowing and blackening of the final product.
[0032] It should be noted that, in this specification, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprises..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.
[0033] Although the content of the utility model has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the utility model. After reading the above content, various modifications and substitutions of the utility model will be obvious to those skilled in the art. Therefore, the protection scope of the utility model should be limited by the attached claims.
Claims
1. A valve needle, comprising a valve needle hanging platform, a valve stem and a valve needle head, characterized in that: The valve stem comprises: a first section, one end of which is connected to the tail of the valve stem; a second segment, one end of the second segment being connected to the other end of the first segment; a third section, one end of the third section being connected to the other end of the second section, and the other end of the third section being connected to the valve needle head; The first section, the second section and the third section are coaxially connected in sequence.
2. The valve needle according to claim 1, characterized in that The diameter of the first section is larger than the diameter of the third section, and the diameter of the second section is smaller than the diameter of the third section.
3. The valve needle according to claim 1, characterized in that Also included: a pair of transition pieces; A transition piece is provided at the connection between the first section and the second section, for smoothly connecting the first section and the second section; Another transition piece is arranged at the connection between the second section and the third section, and is used for smoothly connecting the second section and the third section.
4. The valve needle according to claim 1 or 2, characterized in that: The cross section of the second section is circular.
5. A hot runner system, characterized in that: Comprising: the valve needle, the flow divider, the flow divider plate and the nozzle as described in any one of claims 1 to 4; The flow diversion channel is opened inside the flow diversion plate; The flow channel opening of the branch channel is connected to the nozzle, and the molten plastic is branched through the branch channel and flows to the nozzle; The valve needle is arranged at the flow channel opening of the branch flow channel.