Top pin anti-stuck structure of automobile navigation rear cover injection mold
By using a multi-seal structure of sealing rings and airbags, along with a cooling chamber design, in the injection mold for the rear cover of the car navigation system, the problem of ejector pin jamming was solved, enabling smooth ejection of the workpiece and efficient operation of the production process, thereby improving product quality and mold life.
Patent Information
- Application Number
- CN202521103872.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Filing Date
- 2025-05-30
- Publication Date
- 2026-07-07
- Estimated Expiration
- 2035-05-30
AI Technical Summary
The ejector pins of existing car navigation system back cover injection molds are prone to jamming during use due to the plastic melt seeping into the gap of the slide, which prevents the workpiece from being ejected smoothly, affecting production speed and product quality.
It adopts a multi-seal structure with sealing rings and airbags. The airbag expands and squeezes the sealing ring into the sealing groove to form an all-round seal, preventing the plastic melt from seeping into the gap between the ejector rod and the slide. Combined with springs and locking bolts, it ensures the accurate positioning of the ejector rod and uses a cooling chamber to quickly cool the injection molding material.
It effectively prevents ejector pin jamming, ensures smooth ejection of workpieces, improves production efficiency and product quality, reduces mold wear, and increases production speed and output.
Smart Images
Figure CN224465137U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of injection mold technology, specifically, it relates to the ejector pin anti-jamming structure of the injection mold for the rear cover of an automobile navigation system. Background Technology
[0002] Currently, the injection molding process for the back cover of a car navigation system mainly involves injecting molten plastic into the mold cavity, allowing it to cool and solidify, and then ejecting the workpiece from the mold through a specific ejection mechanism. To facilitate the smooth ejection of the injection-molded workpiece from the mold, an ejector pin structure is usually added to the bottom of the mold. The ejector pin can slide in the groove of the mold and eject the workpiece by moving upward.
[0003] However, in actual use, existing ejector pins for ejecting injection-molded workpieces can easily become stuck due to the high fluidity of the molten plastic during injection molding. This can cause the molten plastic to seep into the gap between the ejector pin and the groove, forming plastic residue after cooling and solidification. Once stuck, the workpiece cannot be ejected smoothly, leading to production stoppage and affecting production speed and output. Furthermore, forced ejection may cause workpiece deformation and damage, reducing product qualification rate. Therefore, this utility model is proposed. Utility Model Content
[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide an ejector pin anti-jamming structure for the injection mold of the rear cover of a car navigation system that can overcome the above problems or at least partially solve the above problems.
[0005] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by this utility model is as follows:
[0006] An anti-jamming structure for the ejector pin of an injection mold for a car navigation system back cover includes a mold box and further includes: a sliding groove penetrating the bottom of the mold box, wherein an ejector rod is slidably connected within the sliding groove, the ejector rod being used to eject the injection-molded workpiece out of the mold box; a sealing ring, fixedly installed on the outer wall of the ejector rod and fitting against the inner wall of the sliding groove; an annular airbag, embedded in the outer wall of the ejector rod, with the sealing ring located outside the airbag; and an air supply pipe with a solenoid valve, disposed within the ejector rod and connected to the airbag.
[0007] To increase the sealing between the push rod and the slide groove, preferably, multiple sealing grooves arranged in a ring shape are equidistantly on the groove wall of the slide groove, and the sealing grooves are used in conjunction with the sealing ring.
[0008] To facilitate ejecting the molded workpiece from the mold box, preferably, a sleeve is fixedly installed at the bottom of the mold box, a slider is slidably connected inside the sleeve, the ejector rod is fixedly connected to the slider, a spring is provided inside the sleeve, one end of the spring is fixedly connected to the slider, and the other end is fixedly connected to the inner wall of the sleeve, the air supply pipe extends from one end of the slider to the outside of the sleeve, a pull rope is fixedly connected to the slider, and a pull ring is fixedly connected to one end of the pull rope that passes through the lower end of the sleeve.
[0009] To further lock and limit the slider, a locking hole is provided on the slider, and a locking bolt that is threadedly connected to the locking hole is inserted into the sleeve.
[0010] To facilitate precise alignment of the locking bolt with the locking hole, a limiting ring is integrally formed on the inner wall of the sleeve, and the slider abuts against the limiting ring.
[0011] To accelerate liquid cooling and molding, preferably, a cooling cavity is provided between the inner and outer walls of the mold box, and an inlet pipe connected to the cooling cavity is provided at the bottom of the mold box, and an outlet pipe connected to the cooling cavity is provided on the top side wall.
[0012] By adopting the above technical solution, this utility model has the following beneficial effects compared with the prior art:
[0013] This invention, through the initial fit between the sealing ring and the sealing groove, and the multiple sealing structures formed by the expansion of the airbag and the compression of the sealing ring into the sealing groove, comprehensively prevents the plastic melt from seeping into the gap between the ejector rod and the slide groove. This effectively solves the problem of ejector rod jamming caused by plastic residue, ensures smooth ejection of the workpiece, avoids production stoppage caused by ejection failure, makes the injection molding process smoother and more efficient, and can effectively improve the production speed and output of products. Attached Figure Description
[0014] Figure 1 This is a cross-sectional view of the mold and sleeve of this utility model. Figure 1 ;
[0015] Figure 2 This is a cross-sectional view of the mold and sleeve of this utility model. Figure 2 ;
[0016] Figure 3 This is a schematic diagram of the internal structure of the sleeve of this utility model;
[0017] Figure 4 This is a schematic diagram of the structure of this utility model;
[0018] Figure 5 This is a utility model Figure 1 Enlarged view of section A;
[0019] Figure 6This is a utility model Figure 2 Enlarged view of section B.
[0020] In the diagram: 1. Mold box; 101. Cooling chamber; 102. Liquid inlet pipe; 103. Liquid outlet pipe; 2. Push rod; 201. Sealing ring; 3. Sleeve; 301. Slider; 302. Spring; 303. Pull rope; 304. Pull ring; 305. Limiting ring; 306. Locking bolt; 4. Airbag; 401. Air supply pipe; 402. Sealing groove. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this utility model, but are not intended to limit the scope of this utility model.
[0022] Example 1:
[0023] Reference Figure 1 , Figure 3 , Figure 4 , Figure 5 The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system includes a mold box 1, and further includes: a sliding groove penetrating the bottom of the mold box 1, wherein an ejector rod 2 is slidably connected in the sliding groove, the ejector rod 2 being used to eject the injection-molded workpiece out of the mold box 1; a sealing ring 201, which is fixedly installed on the outer wall of the ejector rod 2 and fits against the inner wall of the sliding groove; an annular airbag 4, which is embedded in the outer wall of the ejector rod 2, with the sealing ring 201 located on the outside of the airbag 4; and an air supply pipe 401 with a solenoid valve, which is located inside the ejector rod 2 and connected to the airbag 4.
[0024] Multiple sealing grooves 402 arranged in a ring shape are equally spaced on the groove wall of the slide. The sealing grooves 402 are used in conjunction with the sealing rings 201.
[0025] Before injection molding, the ejector pin 2 is reset and flush with the bottom inner wall of the mold box 1. At this time, the sealing ring 201 and the sealing groove 402 are naturally fitted together, which initially increases the sealing between the ejector pin 2 and the slide. Then, the solenoid valve on the air supply pipe 401 is opened, and air is injected into the air bag 4 through the air supply pipe 401. As the gas is continuously injected, the air bag 4 gradually expands, squeezing the sealing ring 201 to make it fit tightly against the slide groove wall, further enhancing the sealing. At the same time, the expanded air bag 4 squeezes the sealing ring 201 to deform, making it embed into the sealing groove 402, forming a multi-seal structure. This multi-seal design can effectively prevent the plastic melt from seeping into the gap between the ejector pin 2 and the slide when the plastic melt is injected into the mold box 1, and avoid the formation of plastic residue after cooling and solidification, which would cause the ejector pin 2 to get stuck.
[0026] After completing the above sealing and strengthening steps, the molten plastic can be poured into the mold cavity in the mold box 1 for injection molding. Due to the multiple sealing structure between the ejector pin 2 and the slide, the penetration of the molten plastic can be reliably blocked, ensuring the smooth progress of the injection molding process.
[0027] After injection molding, the solenoid valve on the air supply pipe 401 is first opened to release the gas in the airbag 4, causing the airbag 4 to contract and the deformation of the sealing ring 201 to be restored. Then, the ejector rod 2 is driven by the drive mechanism to slide upward in the slide groove, ejecting the injection-molded workpiece out of the mold box 1. Since the gap between the ejector rod 2 and the slide groove is not penetrated by the plastic melt during the injection molding process, the ejector rod 2 can slide smoothly, effectively avoiding ejection failure caused by jamming.
[0028] In summary, through the initial fit between the sealing ring 201 and the sealing groove 402, and the multiple sealing structures formed by the expansion of the airbag 4 and the compression of the sealing ring 201 into the sealing groove 402, the plastic melt can be prevented from seeping into the gap between the ejector rod 2 and the slide groove in all directions. This effectively solves the problem of the ejector rod 2 getting stuck due to plastic residue, ensures that the workpiece is ejected smoothly, reduces quality problems such as workpiece deformation and damage caused by poor ejection, and improves the product qualification rate.
[0029] This reduces the need for frequent mold disassembly for cleaning or maintenance due to ejector pin 2 jamming, thus reducing mold wear, extending mold lifespan, and saving production costs.
[0030] It avoids production stoppages caused by ejection failures, making the injection molding process smoother and more efficient, and effectively improving product production speed and output.
[0031] Example 2:
[0032] Reference Figure 1 , Figure 2 , Figure 3 , Figure 6 The ejector pin anti-jamming structure of the injection mold for the rear cover of the car navigation system is basically the same as that in Embodiment 1. Furthermore, a sleeve 3 is fixedly installed at the bottom of the mold box 1, a slider 301 is slidably connected inside the sleeve 3, an ejector rod 2 is fixedly connected to the slider 301, a spring 302 is provided inside the sleeve 3, one end of the spring 302 is fixedly connected to the slider 301, and the other end is fixedly connected to the inner wall of the sleeve 3, an air supply pipe 401 extends from one end of the slider 301 to the outside of the sleeve 3, a pull rope 303 is fixedly connected to the slider 301, and a pull ring 304 is fixedly connected to one end of the pull rope 303 that passes through the lower end of the sleeve 3.
[0033] The slider 301 has a locking hole, and the sleeve 3 has a locking bolt 306 that is threadedly connected to the locking hole.
[0034] The inner wall of the sleeve 3 is integrally formed with a limiting ring 305, and the slider 301 abuts against the limiting ring 305.
[0035] Before injection molding, the ejector pin 2 is reset: Pull the pull ring 304, and the pull rope 303 drives the slider 301 to slide downward in the sleeve 3, compressing the spring 302, so that the ejector pin 2 descends to the position flush with the bottom inner wall of the mold box 1. When the slider 301 slides down to abut against the limit ring 305, the limit ring 305 restricts the further movement of the slider 301, ensuring that the ejector pin 2 is accurately reset. Then, screw the locking bolt 306 into the locking hole of the slider 301, and fix the slider 301 in the sleeve 3 through the threaded connection to prevent the ejector pin 2 from moving accidentally and to ensure the sealing of the mold and the quality of injection molding.
[0036] Ejecting the workpiece after injection molding: Unscrew the locking bolt 306 to release the lock on the slider 301, then open the solenoid valve on the air supply pipe 401 to release the gas in the airbag 4, causing the airbag 4 to contract and the sealing ring 201 to return to its initial state. At this time, the compressed spring 302 generates thrust, pushing the slider 301 to slide upward. The slider 301 drives the ejector rod 2 to move upward synchronously in the groove, thereby ejecting the injection molded workpiece from the mold box 1.
[0037] In summary, the limiting ring 305 ensures that the slider 301 slides down accurately, making the ejector pin 2 flush with the bottom inner wall of the mold box 1, thus ensuring the sealing of the mold, preventing the leakage of plastic melt during injection molding, and improving product quality.
[0038] The elastic potential energy of spring 302 is converted into ejection force, realizing the automatic ejection of ejector rod 2, which simplifies the operation process and improves production efficiency.
[0039] Example 3:
[0040] Reference Figure 1 The ejector pin anti-jamming structure of the injection mold for the rear cover of the car navigation system is basically the same as that in Embodiment 1. Furthermore, a cooling cavity 101 is provided between the inner and outer walls of the mold box 1. The bottom of the mold box 1 is provided with an inlet pipe 102 connected to the cooling cavity 101, and the top side wall is provided with a drain pipe 103 connected to the cooling cavity 101.
[0041] During the injection molding process, coolant (such as water or a specific cooling medium) is introduced into the cooling chamber 101 through the inlet pipe 102. The coolant flows in the cooling chamber 101, absorbing the heat of the injection molding material in the mold box 1, thereby cooling the mold box 1. The cooled coolant flows out from the drain pipe 103. This circulating cooling method can effectively reduce the temperature of the mold box 1, allowing the injection molding material to cool and solidify quickly, thus improving the injection molding production efficiency.
[0042] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model.
Claims
1. An ejector pin anti-jamming structure for an injection mold of a car navigation system back cover, comprising a mold box (1), characterized in that, Also includes: A sliding groove runs through the bottom of the mold box (1), wherein a push rod (2) is slidably connected in the sliding groove, and the push rod (2) is used to push the injection-molded workpiece out of the mold box (1). The sealing ring (201) is fixedly installed on the outer wall of the top rod (2) and fits against the inner wall of the groove; An airbag (4) arranged in a ring shape is embedded in the outer wall of the top rod (2), and the sealing ring (201) is located on the outside of the airbag (4); An air supply pipe (401) with a solenoid valve is disposed inside the top rod (2) and is connected to the air bag (4).
2. The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system according to claim 1, characterized in that, The groove wall is provided with a plurality of sealing grooves (402) arranged in a ring at equal intervals, and the sealing grooves (402) are used in conjunction with the sealing rings (201).
3. The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system according to claim 1, characterized in that, A sleeve (3) is fixedly installed at the bottom of the mold box (1). A slider (301) is slidably connected inside the sleeve (3). The top rod (2) is fixedly connected to the slider (301). A spring (302) is provided inside the sleeve (3). One end of the spring (302) is fixedly connected to the slider (301), and the other end is fixedly connected to the inner wall of the sleeve (3). The gas supply pipe (401) extends from one end of the slider (301) to the outside of the sleeve (3). A pull rope (303) is fixedly connected to the slider (301). A pull ring (304) is fixedly connected to one end of the pull rope (303) at the lower end of the sleeve (3).
4. The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system according to claim 3, characterized in that, The slider (301) has a locking hole, and the sleeve (3) has a locking bolt (306) that is threadedly connected to the locking hole.
5. The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system according to claim 4, characterized in that, The inner wall of the sleeve (3) is integrally formed with a limiting ring (305), and the slider (301) abuts against the limiting ring (305).
6. The ejector pin anti-jamming structure of the injection mold for the rear cover of a car navigation system according to claim 1, characterized in that, A cooling cavity (101) is provided between the inner and outer walls of the mold (1). The bottom of the mold (1) is provided with an inlet pipe (102) connected to the cooling cavity (101), and the top side wall is provided with a drain pipe (103) connected to the cooling cavity (101).