Seal structure
By using the combination structure of the inner core of PP material and the outer surface layer of the POM-based material in the seal, the problem of poor surface of the POM-based material seal during injection molding is solved, and the effect of shortening the production cycle and reducing costs is achieved.
Patent Information
- Application Number
- CN202421821055.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-07-30
AI Technical Summary
During injection molding, the existing POM-based material seals have flow patterns and pores on the surface due to the thickness of the glue, which requires long-term grinding and low efficiency and high cost.
The structure is adopted for a combined structure of the inner core and the outer surface layer of the POM-based material. The inner core is made of PP material. The outer surface layer is molded on the surface of the inner core by integral injection molding, forming a thin peripheral wall portion with consistent wall thickness and a face.
The flow marks and pore problems during injection molding are avoided, the grinding time is reduced, the production cycle is shortened, and the product cost is reduced by using lower-cost PP materials.
Smart Images
Figure CN222921280U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of seals. Background Art
[0002] Because POM (Polyoxymethylene) plastic has high hardness, excellent strength and rigidity, and has good wear resistance, fatigue resistance, solvent resistance, corrosion resistance, and self-lubricating properties, etc., it has become the preferred material for making seals. The POM materials used for seals include pure POM plastic and POM composite materials containing a small amount of other components, which are collectively referred to as POM-based materials. When making a seal by injecting the POM-based material through a mold, due to the large diameter of the seal and the very thick rubber position of the POM-based material, there are surface defects such as flow marks and air holes on the surface of the seal. Not only does the injection time take longer, but also surface treatment is required. The surface treatment method is grinding, that is, putting a batch of seals into a grinding device for grinding for dozens of hours to make its surface smooth. The efficiency of producing seals in this way is low. In addition, the cost of POM materials is relatively high, so it is necessary to improve it to enhance market competitiveness. Summary of the Utility Model
[0003] The purpose of the utility model is to provide a seal structure that can improve production efficiency and reduce product cost.
[0004] To achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0005] A seal structure includes an inner core body and an outer surface layer of POM-based material combined with the outer surface of the inner core body. The outer surface layer includes a peripheral wall portion that fits on the outer peripheral surface of the inner core body and has a substantially uniform wall thickness, and a seal surface portion corresponding to the bottom surface of the inner core body. The thickness of the peripheral wall portion is not greater than the thickness of the seal surface portion.
[0006] A preferred solution is that the outer surface layer is integrally injection molded on the surface of the inner core body.
[0007] A preferred solution is that the inner core body has a rotationally symmetric structure around a vertical central axis, and a positioning blind hole is provided along the central axis at the top end of the inner core body.
[0008] A preferred solution is that the peripheral wall portion and the seal surface portion are of a split structure. The peripheral wall portion is sleeved on the outer peripheral wall of the inner core body, and the seal surface portion is fixed to the bottom surface of the inner core body.
[0009] A preferred solution is that the bottom end of the peripheral wall portion extends beyond the bottom end surface of the inner core body and wraps around the outer peripheral wall of the seal surface portion, and the bottom end surface of the peripheral wall portion is flush with the bottom surface of the seal surface portion.
[0010] A preferred solution is that the inner core is a component made of PP (Polypropylene).
[0011] A preferred solution is that the inner core includes a cylindrical seal body and a handle concentrically formed on the upper part of the seal body.
[0012] The beneficial effects of the present utility model are as follows: The seal is provided with an inner core and an outer surface layer of POM-based material. On the one hand, while retaining the excellent properties of POM material, the relatively thin outer surface layer can avoid flow marks and air holes during injection molding, so that the surface of the seal does not need to be polished for a long time, and the single molding cycle can also be significantly shortened. Therefore, the product production cycle can be greatly shortened. On the other hand, the inner core that accounts for most of the volume of the seal can be made of other materials, such as PP plastic, which can significantly reduce the product cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present utility model will be further described in detail below with reference to the drawings and specific embodiments.
[0014] Figure 1 It is a schematic cross-sectional structure diagram of the seal in Embodiment 1;
[0015] Figure 2 It is a schematic cross-sectional structure diagram of the seal in Embodiment 2. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] The present utility model will be further described below with reference to the drawings:
[0017] Embodiment 1:
[0018] Referring to Figure 1 shown, a seal structure includes an inner core 1 made of PP material and an outer surface layer 2 of POM-based material combined on the outer surface of the inner core 1. The inner core 1 includes a cylindrical seal body 11 and a handle 12 concentrically formed on the upper part of the seal body 11. The outer surface layer 2 includes a peripheral wall portion 21 that fits on the outer peripheral surface of the inner core 1 and has a substantially uniform wall thickness, and a seal face portion 22 corresponding to the bottom surface of the inner core 1. The thickness of the peripheral wall portion 21 is not greater than the thickness of the seal face portion 22. The outer surface layer 2 is integrally injection-molded on the surface of the inner core 1. The inner core 1 has a rotationally symmetric structure about the vertical central axis, and a positioning blind hole 100 is provided along the central axis at the top end of the inner core 1.
[0019] During production, first, the inner core 1 is injection-molded. Then, the inner core 1 is fixed in the mold through the positioning blind hole 100 at the top. Next, the outer surface layer 2 made of POM-based material is injection-molded on the outer surface of the inner core 1, and thus the production of the seal is completed. Among them, the POM-based material can be pure POM material or POM composite material containing a small amount of other components. The thickness of the seal face part 22 is set to be about 5 mm, and the thickness of the peripheral wall part 21 is about 2 - 3 mm. In other embodiments, of course, a positioning rod protruding from the top surface of the inner core 1 can be used to replace the positioning blind hole 100, and the inner core 1 can also be fixed in the mold.
[0020] The seal is set to have an inner core 1 and an outer surface layer 2 made of POM-based material. On the one hand, while retaining the excellent performance of the POM material, the relatively thin outer surface layer 2 can avoid the generation of flow marks and air holes during injection molding, so that the surface of the seal does not need to be polished for a long time, and the single molding cycle can also be significantly shortened. Therefore, the product production cycle can be greatly shortened. On the other hand, the inner core 1 that occupies most of the volume of the seal can be made of other materials, such as PP plastic, which can significantly reduce the product cost.
[0021] Embodiment 2:
[0022] Reference Figure 2 As shown, a seal structure has the same basic structure as that in Embodiment 1, and the difference lies in that: the peripheral wall part 21 and the seal face part 22 are of a split structure. The peripheral wall part 21 is sleeved on the outer peripheral wall of the inner core 1, and the seal face part 22 is fixed to the bottom surface of the inner core 1.
[0023] During production, first, the inner core 1, the peripheral wall part 21 and the seal face part 22 of the outer surface layer 2 are respectively injection-molded. Then, the peripheral wall part 21 is sleeved and fixed on the outer peripheral wall of the inner core 1, and then the seal face part 22 is fixed to the bottom surface of the inner core 1. Compared with the prior art, this production method also does not require grinding the outer surface of the seal.
[0024] In a preferred solution, the bottom end of the peripheral wall part 21 of this embodiment extends beyond the bottom end face of the inner core 1 and wraps around the outer peripheral wall of the seal face part 22, and the bottom end face of the peripheral wall part 21 is flush with the bottom surface of the seal face part 22. At this time, the bottom surface of the peripheral part can be directly used as the outer frame of the seal pattern.
[0025] The above does not impose any limitation on the technical scope of the present invention. Any modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solutions of the present invention.
Claims
1. A seal structure, characterized in that: It includes an inner core body and an outer layer of a POM-based material bonded to the outer surface of the inner core body, wherein the outer layer includes a peripheral wall portion which is attached to the peripheral surface of the inner core body and has a substantially uniform wall thickness, and a chapter face portion corresponding to the bottom surface of the inner core body, wherein the thickness of the peripheral wall portion is not greater than the thickness of the chapter face portion.
2. A seal structure according to claim 1, characterized in that: The outer layer is integrally injection-molded on the surface of the inner core.
3. A seal structure according to claim 2, characterized in that: The inner core body is a rotationally symmetrical structure around a vertical central axis, and a positioning blind hole is provided at the top end of the inner core body along the central axis.
4. A seal structure according to claim 1, characterized in that: The peripheral wall portion and the seal face portion are separate structures. The peripheral wall portion is sleeved on the outer peripheral wall of the inner core body, and the seal face portion is fixed to the bottom surface of the inner core body.
5. A seal structure according to claim 4, characterized in that: The bottom end of the peripheral wall portion exceeds the bottom end surface of the inner core body and covers the outer peripheral wall of the chapter face portion, and the bottom end surface of the peripheral wall portion is flush with the bottom surface of the chapter face portion.
6. A seal structure according to claim 1, characterized in that: The inner core is a PP material component.
7. A seal structure according to claim 1, characterized in that: The inner core comprises a cylindrical seal body and a handle concentrically formed on the upper part of the seal body.