Injection mold for anti-pulling rubber powder
By setting coaxial through holes and chamfered structures in the injection mold, the problems of powder pulling and misalignment of the ejector pin holes were solved, improving product quality and production efficiency, and extending the service life of the mold.
Patent Information
- Application Number
- CN202520073597.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-01-13
AI Technical Summary
During the demolding process of injection molds, the upper edge of the ejector pin hole is prone to producing glue powder, resulting in surface defects on the product and unevenness of the mold. In addition, the ejector pin is prone to being pushed off-center, affecting product quality and production efficiency.
An injection mold for anti-pull adhesive powder was designed. By setting a first through hole and a second through hole coaxially connected in the ejector pin channel, and setting a first chamfer structure at the connection between the first through hole and the lower template, the diameter of the first through hole is larger than that of the second through hole. Combined with the limiting protrusion and the chamfer structure, the adhesive material sticking and ejector pin displacement are prevented.
It effectively prevents powdery residue buildup, improves product yield, enhances ejector pin smoothness, shortens demolding time, extends mold life, and reduces production costs.
Smart Images
Figure CN223918507U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to injection mold technical field especially is related to a kind of injection mold of preventing pulling rubber powder. BACKGROUND
[0002] At present, in the production process of injection mold product, first by hot melt rubber injection forming cavity, then after the hot melt rubber in forming cavity cooling and shaping to obtain the product of forming, finally product is ejected by ejector pin mechanism and smoothly demoulding.
[0003] In prior art, ejector pin mechanism generally includes ejector pin and ejector pin panel, ejector pin panel is movably arranged below lower die plate, and ejector pin is installed on ejector pin panel and penetrates lower die plate from bottom to top;When demoulding, ejector pin panel drives ejector pin to rise, and ejector pin penetrates lower die plate and ejects product, and lower die plate is provided with ejector pin hole corresponding to the penetration of ejector pin, and the ejector pin hole is through hole.
[0004] However, in the process of demoulding, the upper end edge of the ejector pin hole is prone to pulling rubber powder, that is, some small rubber particles or powder are left on the upper end edge of the through hole, which not only causes defects on the surface of the product, but also causes the upper surface of the lower die plate to be uneven, so that the rubber overflow is out of the PL surface of the mold, and finally the product produces problems such as burr, burr and the like, which affects the appearance and quality of the product.
[0005] In addition, since the diameter of ejector pin is small, the diameter of the ejector pin hole is also small, and the ejector pin is prone to deviation when ejecting the product, on the one hand, the product is extruded into the ejector pin hole, which causes the demoulding to be not smooth, resulting in long demoulding time, on the other hand, the product is even extruded into the upper end edge of the ejector pin hole, which is prone to pulling rubber powder. UTILITY MODEL CONTENTS
[0006] The utility model aims at providing a kind of injection mold of preventing pulling rubber powder, to solve or at least partially solve the deficiencies in the prior art, which can prevent the phenomenon of pulling rubber powder at the end of ejector pin hole when demoulding, improve product yield;At the same time, it can improve the problem of deviation of ejector pin when ejecting product, and improve production efficiency.
[0007] The utility model provides a kind of injection mold of anti-pulling rubber powder, including upper die plate, lower die plate and ejector pin mechanism, and the forming die cavity for forming product body is provided between upper die plate and lower die plate, and the ejector pin mechanism includes ejector pin, and the ejector pin is from below and upwards and penetrates lower die plate, and lower die plate is provided with ejector pin channel corresponding to ejector pin, and the ejector pin can be inserted into or withdrawn from forming die cavity along ejector pin channel, and the ejector pin channel includes first through hole and second through hole, and the first through hole is coaxially communicated with the second through hole, and the first through hole is communicated with forming die cavity and located above the second through hole, and the second through hole is matched with ejector pin, and the diameter of first through hole is greater than the diameter of second through hole, and first chamfer structure is provided at the junction of first through hole and the upper surface of lower die plate.
[0008] Further, the first chamfer structure is an oblique angle, and the included angle α between the inclined surface of the oblique angle and the upper surface of the lower die plate is 68°-80°.
[0009] Further, the junction of the first chamfer structure and the hole wall of the first through hole is smoothly transitioned.
[0010] Further, the spacing L between the hole wall of the first through hole and the hole wall of the second through hole is 0.3-0.5 mm.
[0011] Further, the junction of the first through hole and the second through hole is provided with a second chamfer structure.
[0012] Further, the second chamfer structure has a first end and a second end, the first end is connected with the hole wall of the first through hole, and the second end is connected with the hole wall of the second through hole.
[0013] Further, the top end of the ejector pin is provided with a limiting protrusion upward along the axis, and the limiting protrusion protrudes in the first through hole during injection molding.
[0014] Further, one side of the ejector pin connected with the limiting protrusion is an abutting surface, and the abutting surface and the second end are in the same plane during injection molding.
[0015] Further, the ejector pin mechanism further includes an ejector pin plate movably arranged below the lower die plate, and the lower end of the ejector pin is connected with the ejector pin plate.
[0016] Further, the lower die plate is detachably embedded with an ejector pin sleeve, and the ejector pin channel is arranged on the ejector pin sleeve.
[0017] The injection mold for preventing rubber powder pulling of the utility model, through setting up first chamfer structure, make the corner of the connection of first through hole and the upper surface of lower mold plate more gentle, avoid the rubber material to stick together and remain in the top end edge of first through hole when demolding, thereby prevent the rubber powder to project from the upper surface of lower mold plate and cause the concave-convex condition, further prevent the rubber material to overflow the PL surface of mold and cause the product to produce the flange, the edge, finally improve the product yield; Through setting up the diameter of first through hole is greater than the diameter of second through hole, can improve the problem that the ejector pin will appear to top when ejecting product, make the demolding smooth, shorten the demolding time, improve the production efficiency, also prevent the phenomenon of pulling rubber powder. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 It is the cross section schematic view of the injection mold for preventing rubber powder pulling of the utility model embodiment 1.
[0019] Figure 2 It is Figure 1 It is the schematic view of the first chamfer structure.
[0020] Figure 3 It is Figure 2 It is the schematic view of the second chamfer structure.
[0021] Figure 4 It is Figure 2 It is the cross section schematic view of the injection mold for preventing rubber powder pulling of the utility model embodiment 2.
[0022] Figure 5 It is the cross section schematic view of the injection mold for preventing rubber powder pulling of the utility model embodiment 2.
[0023] Figure 6 It is Figure 5 It is the cross section schematic view of the injection mold for preventing rubber powder pulling of the utility model embodiment 2.
[0024] Figure 7 It is the schematic view of the product in the utility model.
[0025] Figure 8 It is Figure 7 It is the schematic view of the product in the utility model. DETAILED DESCRIPTION
[0026] The specific implementation of the utility model is described in further detail below in conjunction with the drawings and examples. The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.
[0027] The terms "first", "second", "third", "fourth" and the like (if exist) in the specification and claims of the utility model are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence.
[0028] The up, down, left, right, front, back, top, bottom and other (if any) orientation words in the description and claims of the utility model are defined by the position of the structure in the drawing and the position of the structure relative to each other in the drawing, only to express the clear and convenient of the technical scheme. It should be understood that the use of orientation words should not limit the scope of the application claimed.
[0029] Embodiment 1:
[0030] Please refer to Figure 1 , Figure 2 and Figure 7 , an injection mold for preventing pulling of rubber powder, comprising an upper mold plate 10, a lower mold plate 20 and a ejector pin mechanism 30, a molding cavity 40 for molding a product body 101 is arranged between the upper mold plate 10 and the lower mold plate 20, the ejector pin mechanism 30 comprises an ejector pin 31, the ejector pin 31 penetrates the lower mold plate 20 from bottom to top, the lower mold plate 20 is provided with an ejector pin channel 21 corresponding to the ejector pin 31, and the ejector pin 31 can extend into or exit the molding cavity 40 along the ejector pin channel 21.
[0031] The ejector pin channel 21 comprises a first through hole 211 and a second through hole 212, the first through hole 211 and the second through hole 212 are coaxially and communicatively arranged, the first through hole 211 is communicatively arranged with the molding cavity 40 and located above the second through hole 212, the second through hole 212 is matched with the ejector pin 31, the diameter of the first through hole 211 is greater than that of the second through hole 212, and a first chamfer structure 213 is arranged at the connection between the first through hole 211 and the upper surface of the lower mold plate 20.
[0032] During injection molding, the molten rubber material is injected and filled into the molding cavity 40 and the first through hole 211.
[0033] After the rubber material cools down, the rubber material is hardened to form the product body 101 and the residual part 102 in the molding cavity 40 and the first through hole 211 respectively, since the residual part 102 has a small volume and is located on the inner surface of the product body 101, it does not affect the appearance and function of the product body 101, and cutting is not required, so the product body 101 and the residual part 102 form the product 100.
[0034] During demolding, the ejector pin 31 upwardly abuts against the product 100 to drive the product 100 to separate from the lower mold plate 20.
[0035] From the above, the injection mold for preventing the pulling of the powder is provided by the embodiments of the present utility model, through setting first chamfer structure 213, make the corner of the connection of first through hole 211 and the upper surface of lower mold plate 20 more gentle, avoid the sticking and remaining of the rubber material at the top edge of first through hole 211 when demolding, thereby prevent the protrusion of the powder on the upper surface of lower mold plate 20 to cause the concave-convex condition, further prevent the overflow of the rubber material from the PL surface of the mold to cause the burr and the edge of the product, finally improve the yield of the product; through setting the diameter of first through hole 211 is greater than the diameter of second through hole 212, can improve the problem of the deviation of ejector pin 31 when ejecting product 100, make the demolding smooth, shorten the demolding time, improve the production efficiency, also prevent the phenomenon of pulling the powder.
[0036] Please refer to Figure 3 , the first chamfer structure 213 can be an angle, also can be a round angle, in the embodiment, the first chamfer structure 213 is an angle.
[0037] The angle of the inclined surface of the angle and the upper surface of lower mold plate 20 is 68°~80°. If the angle is too large, the inclination of the angle is too large, which causes the corner to be too sharp, and part of the rubber material is easily adhered to the top edge of first through hole 211 during demolding, thereby causing the phenomenon of pulling the powder; if the angle is too small, the inclination of the angle is too small, which causes the top hole diameter of first through hole 211 to be too large, and the appearance and function of product body 101 are interfered. Through many times of experiments, the angle is in the range of 65°~82°, which can meet the requirements of preventing the pulling of the powder and not interfering with the appearance and function of product body 101. Preferably, the angle is 68°~80°. The angle can be specifically set to 68°, 72°, 76°, 80°, etc. by the person skilled in the art, which is not limited herein.
[0038] Further, the connection between first chamfer structure 213 and the hole wall of first through hole 211 is smooth transition, which can make residual part 102 more easily separate from first through hole 211 and more smooth during ejection.
[0039] Please refer to Figure 4 , the distance L between the hole wall of first through hole 211 and the hole wall of second through hole 212 is 0.3mm~0.5mm.
[0040] If the distance L is too large, the diameter of the first through hole 211 is large, and since the top edge of the first through hole 211 is provided with the first chamfer structure 213, the top hole diameter of the first through hole 211 is too large, which will interfere with the appearance and function of the product body 101. If the distance L is too small, the diameter of the first through hole 211 is similar to the diameter of the ejector pin 31, and when injection molding, the contact area of the residual part 102 and the ejector pin 31 accounts for a large proportion of the lower surface of the residual part 102, so that the ejector pin 31 is more likely to deviate during the ejection process, causing the ejection deviation. After many experiments, the distance L is in the range of 0.25mm~0.6mm, which can improve the ejection deviation problem and meet the requirements of not interfering with the appearance and function of the product body 101. Preferably, the distance L is 0.3mm~0.5mm. Those skilled in the art can set the distance L to 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc., which is not limited here.
[0041] Please refer to Figure 2 and Figure 4 , the connection between the first through hole 211 and the second through hole 212 is provided with a second chamfer structure 214. The second chamfer structure 214 can avoid the glue from sticking to the connection between the first through hole 211 and the second through hole 212 during ejection, preventing the residual powder in the first through hole 211 from affecting the normal use of the mold.
[0042] More specifically, the second chamfer structure 214 has a first end 2141 and a second end 2142, the first end 2141 is connected with the hole wall of the first through hole 211, and the second end 2142 is connected with the hole wall of the second through hole 212.
[0043] Please refer to Figure 2 , Figure 4 and Figure 8 , the top end of the ejector pin 31 is provided with a limiting protrusion 311 along the axis, which protrudes into the first through hole 211 during injection molding; after the product is molded, the limiting protrusion 311 makes the residual part 102 have a limiting groove 1021, and the limiting protrusion 311 cooperates with the limiting groove 1021; during demolding, the limiting protrusion 311 upwardly abuts against the limiting groove 1021, and the cooperation between the limiting protrusion 311 and the limiting groove 1021 can further prevent the ejector pin 31 from deviating.
[0044] More specifically, the end of the limiting protrusion 311 is provided with a third chamfer structure 3111, which is a round corner, and the third chamfer structure 3111 can make the residual part 102 more easily fall off during demolding to prevent the residual powder.
[0045] Further, the side of the ejector pin 31 connected with the limiting protrusion 311 is an abutting surface 312, which is in the same plane with the second end 2142 during injection molding. This arrangement can ensure the flatness of the outer surface of the residual part 102 as much as possible, so as to prevent the phenomenon of pulling plastic powder of the residual part 102 in the first through hole 211 during demolding.
[0046] Please refer to Figure 1 The ejector pin mechanism 30 further comprises an ejector pin plate 32 movably arranged below the lower die plate 20, and the lower end of the ejector pin 31 is connected with the ejector pin plate 32. During demolding, the ejector pin plate 32 is lifted to drive the ejector pin 31 to push the product 100 upward.
[0047] Embodiment 2:
[0048] An injection mold for preventing pulling plastic powder, which is similar to the injection mold for preventing pulling plastic powder in Embodiment 1 in structure, and the difference is that:
[0049] Please refer to Figure 5 and Figure 6 The lower die plate 20 is detachably embedded with an ejector pin sleeve 22, and the ejector pin channel 21 is arranged through the ejector pin sleeve 22.
[0050] Due to the long-term use of the mold, the ejector pin 31 and the ejector pin channel 21 will be worn out, and the ejector pin 31 and the ejector pin sleeve 22 can be directly replaced, so that the lower die plate 20 can be avoided from being worn out, the service life of the lower die plate 20 is prolonged, and the production cost is reduced.
[0051] The injection mold for preventing pulling plastic powder has the following advantages:
[0052] (1) Prevents the phenomenon of pulling plastic powder, and improves the product yield.
[0053] (2) Improves the problem of ejector pin deviation, and improves the production efficiency.
[0054] (3) Prolongs the service life of the mold, and reduces the production cost.
[0055] The above is only a specific embodiment of the utility model, but the protection scope of the utility model is not limited to this, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the utility model, which should be covered in the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.
Claims
1. A injection mold for preventing pull-out of rubber powder, comprising an upper mold plate (10), a lower mold plate (20) and a ejector pin mechanism (30), a molding cavity (40) for molding a product body (101) is arranged between the upper mold plate (10) and the lower mold plate (20), the ejector pin mechanism (30) comprises an ejector pin (31), the ejector pin (31) penetrates the lower mold plate (20) from bottom to top, the lower mold plate (20) is provided with an ejector pin channel (21) corresponding to the ejector pin (31), the ejector pin (31) can be extended into or withdrawn from the molding cavity (40) along the ejector pin channel (21), characterized in that, The ejector pin channel (21) comprises a first through hole (211) and a second through hole (212), the first through hole (211) and the second through hole (212) are coaxially communicated, the first through hole (211) is communicated with the forming die cavity (40) and is located above the second through hole (212), the second through hole (212) is matched with the ejector pin (31), the diameter of the first through hole (211) is larger than that of the second through hole (212), and a first chamfer structure (213) is arranged at the connection position of the first through hole (211) and the upper surface of the lower die plate (20).
2. The anti-pulling powder injection mold of claim 1, wherein, The first chamfer structure (213) is an inclined angle, and the included angle α between the inclined surface of the inclined angle and the upper surface of the lower die plate (20) is 68°-80°.
3. The anti-pulling powder injection mold of claim 2, wherein, The first chamfer structure (213) is smoothly connected with the hole wall of the first through hole (211).
4. The anti-pulling powder injection mold of claim 1, wherein, The distance L between the hole wall of the first through hole (211) and the hole wall of the second through hole (212) is 0.3-0.5 mm.
5. The anti-pulling powder injection mold of claim 1, wherein, The first through hole (211) and the second through hole (212) are provided with a second chamfer structure (214).
6. The anti-pulling powder injection mold of claim 5, wherein, The second chamfer structure (214) has a first end (2141) and a second end (2142), the first end (2141) is connected with the hole wall of the first through hole (211), and the second end (2142) is connected with the hole wall of the second through hole (212).
7. The anti-pulling powder injection mold of claim 6, wherein, The top end of the ejector pin (31) is provided with a limiting protrusion (311) which protrudes into the first through hole (211) during injection molding.
8. The anti-pulling powder injection mold of claim 7, wherein, One side of the ejector pin (31) connected with the limiting protrusion (311) is an abutting surface (312), and the abutting surface (312) is in the same plane as the second end (2142) during injection molding.
9. The anti-pulling powder injection mold of claim 1, wherein, The ejector pin mechanism (30) further comprises an ejector pin plate (32) movably arranged below the lower die plate (20), and the lower end of the ejector pin (31) is connected with the ejector pin plate (32).
10. The anti-draw powder injection mold of any one of claims 1-9, wherein, The lower die plate (20) is detachably embedded with an ejector pin sleeve (22), and the ejector pin channel (21) is arranged through the ejector pin sleeve (22).