A mold and method for solving the problem of slender thin-walled injection molding dissatisfaction during slider integral injection

Abstract

The present invention relates to the field of injection molds, and provides a mold and method for solving the problem of unsatisfactory injection molding of slender thin-walled products during integral injection molding of a slider. The mold includes a movable mold base, a fixed mold plate, a lower mold core and an upper mold core, and the upper mold core and the lower mold core are buckled to form a cavity; the lower mold core is provided with a through-hole insert pin, and the through-hole insert pin includes a first insert pin and a second insert pin, the first insert pin is provided with a protrusion, and the second insert pin is provided with a groove corresponding to the protrusion, the first insert pin and the second insert pin are connected by the matching of the protrusion and the groove, and a gap is provided between the protrusion and the groove to form an exhaust hole, and a plurality of exhaust grooves are provided on the joint surface of the second insert pin, and the exhaust grooves are connected to the exhaust hole. When the melt flows into the cavity between the through-hole of the slider and the through-hole insert pin, the air in the cavity is squeezed into the exhaust groove, and then discharged from the lower mold core through the exhaust hole, which effectively avoids the situation that the silent pipe sleeve of the slider plastic part is scorched, and solves the problem of unsatisfactory injection molding of slender thin-walled products during integral injection molding of the slider.

Description

Technical Field

[0001] The invention relates to the field of injection molds, and in particular to a mold and a method for solving the problem of unsatisfactory injection molding of slender thin walls during integral injection of a slider. Background Art

[0002] Linear guide is a kind of guide element commonly used in mechanical engineering. It is mainly used to provide linear motion guidance and support for mechanical systems. The slide rail and slider of the linear guide are in contact through balls. This point-to-surface contact method makes the friction resistance very small, so it can achieve subtle movement and high-precision positioning. The slider is composed of metal parts and plastic parts. In recent years, most of the plastic parts of the slider adopt the one-piece injection molding process. This process has the following advantages: one-piece injection molding can simplify the production process of the slider, reduce the assembly and debugging links, and reduce production costs; the slider of the one-piece injection molding does not require additional welding, riveting or bolting steps during the production process, which improves production efficiency; one-piece injection molding can ensure the integrity of the slider plastic parts, thereby improving the overall structural strength and stability of the slider and reducing the risk of deformation or damage; one-piece injection molding can make the silent pipe sleeve, circulating fluid, silent chain belt tensile belt groove and other parts in the rolling element circulation system be injected once, which improves the smoothness of the rolling element and silent chain belt when the slider moves, and reduces the noise when the slider moves.

[0003] There are four through holes in the metal part of the slider for the rolling elements to circulate and roll. During the one-piece injection molding, the slider is placed in the mold core, and the through hole pins are placed in the through holes after the mold is closed. After the injection molding starts, the melt flows into the cavity between the through holes and the through hole pins, and forms a silent tube sleeve in the rolling element circulation system after cooling. Because the through holes are narrow and long, the corresponding through hole pins are thin and long, and the silent tube sleeve is a slender and thin-walled. After the mold is closed, the cavity between the through holes and the through hole pins is a closed space. When the melt flows into the cavity, the air cannot be discharged, and the closed space is in a high-pressure and high-temperature state. When the temperature rises to the ignition point of the melt, the silent tube sleeve will be burned, resulting in holes, which will eventually lead to unsatisfactory injection molding of the product.

[0004] Therefore, how to optimize the mold and allow the melt to flow into the cavity between the through hole and the through hole pin to exhaust the internal air and avoid dissatisfaction of slender and thin-walled injection molding is a problem to be solved. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a mold and method for solving the problem of slender thin-walled injection molding during integral injection of a slider.

[0006] A mold for solving the problem of slender thin-walled injection molding when a slider is integrally packaged, comprising a movable mold base, a fixed mold plate, a lower mold core embedded in the movable mold base and an upper mold core embedded in the fixed mold plate, wherein the upper mold core and the lower mold core are buckled together to form a cavity;

[0007] The lower mold core is provided with a through-hole inlay pin, which includes a first inlay pin and a second inlay pin. The first inlay pin is provided with a protrusion, and the second inlay pin is provided with a groove corresponding to the protrusion. The first inlay pin and the second inlay pin are connected by the cooperation of the protrusion and the groove. A gap is provided between the protrusion and the groove to form an exhaust hole. The joint surface of the second inlay pin is provided with a plurality of exhaust grooves, which are connected to the exhaust hole.

[0008] Furthermore, the protrusions and the grooves are in a dovetail shape.

[0009] Furthermore, the corners of the protrusion and the groove are arc-shaped.

[0010] Furthermore, a gap is provided between the arc-shaped corner of the protrusion and the arc-shaped corner of the groove, thereby forming an exhaust hole that passes through from top to bottom.

[0011] Furthermore, when the melt enters the cavity formed by the through-hole pin and the through-hole, it is necessary to ensure that the air can be discharged and that the melt does not enter the exhaust groove, so the depth of the exhaust groove must be smaller than the overflow value of the melt. The melt overflow value used in the plastic part of the present invention is 0.05 mm, so the depth of the exhaust groove is less than 0.05 mm.

[0012] Preferably, the exhaust groove depth ranges from 0.02 mm to 0.04 mm.

[0013] More preferably, to ensure that there is a margin, the depth of the exhaust groove is 0.03 mm.

[0014] Further, the number of the exhaust slots is six.

[0015] Furthermore, the mold also includes a movable mold base plate and a mold foot, the mold foot is fixedly connected to the movable mold base plate, the movable mold base is fixedly connected to the mold foot, a material shifting plate is provided above the fixed mold plate, and a fixed mold base plate is provided above the material shifting plate.

[0016] A method for solving the problem of slender thin-walled injection molding dissatisfaction during the integral injection of a slider comprises the following steps:

[0017] S1: Fix the injection mold on the injection molding machine and put the metal part of the slider into the lower mold core;

[0018] S2: The injection mold is closed, and the melt is injected into the cavity. When the melt flows into the cavity between the through hole of the metal part of the slider and the through hole insert pin, the air in the cavity is squeezed into the exhaust groove, and then discharged from the lower mold core through the exhaust hole connected to the exhaust groove. Finally, the melt fills the entire cavity. After pressure holding and cooling, a complete plastic part of the silent pipe sleeve is formed;

[0019] S3: Injection mold opening. The injection mold is first separated at the first parting surface. At this time, the plastic part is separated from the runner condensate; then the injection mold is separated at the second parting surface. At this time, the material stripper plate strips the runner condensate away; then the injection mold is separated at the third parting surface. Under the action of the injection molding machine, the slider is ejected by the ejector pin. At this time, one injection molding is completed;

[0020] S4: The injection mold is closed to prepare for the next injection molding.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The through hole pin of the present invention is composed of a first pin and a second pin, which replaces an integrated through hole pin. A gap is provided between the first pin and the second pin to form an exhaust hole, which is combined with an exhaust groove provided on the joint surface of the second pin to form an exhaust system. By designing the depth of the exhaust groove to be smaller than the melt overflow value used in the plastic part of the present invention, air can be discharged from the exhaust groove without the melt entering the exhaust groove. When the melt flows into the cavity between the through hole and the through hole pin, the air in the cavity is squeezed into the exhaust groove and then discharged from the lower mold core through the exhaust hole, which effectively avoids the situation where the air heats up in the closed cavity and burns the silent pipe sleeve, and solves the problem of unsatisfactory injection molding of slender thin walls when the slider is integrally wrapped. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the drawings required for describing the specific implementation or the prior art will be briefly introduced below. Obviously, the drawings described below are only one implementation of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of a mold structure for solving the problem of slender thin-walled injection molding when the slider is integrally packaged in the present invention;

[0025] Figure 2 It is a partial structural diagram of the lower die core being installed on the movable die base;

[0026] Figure 3 yes Figure 2 A partial enlarged view of the middle part;

[0027] Figure 4 This is the bottom view of the lower die core;

[0028] Figure 5 It is a schematic diagram of the overall structure of the slider;

[0029] Figure 6 It is a schematic diagram of the split structure of the slider;

[0030] Figure 7 1. It is a schematic diagram of the overall structure of the through-hole setting needle;

[0031] Figure 8 This is a schematic diagram of the split structure of the through-hole needle;

[0032] Fig. 9 This is a schematic diagram of the structure of the through-hole needle from another perspective.

[0033] The markings in the attached drawings are: 1. movable mold base; 2. fixed mold plate; 3. movable mold base plate; 4. lower mold core; 5. through-hole inlay pin; 51. first inlay pin; 511. protrusion; 52. second inlay pin; 521. joint surface; 522. exhaust groove; 523. groove; 53. exhaust hole; 6. slider; 61. through-hole; 62. plastic part; 621. silent pipe sleeve; 7. mold foot; 8. material stripper plate; 9. fixed mold base plate; 11. first parting surface; 12. second parting surface; 13. third parting surface. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the technical scheme in the specific implementation mode of the present invention is clearly and completely described below to further illustrate the present invention. Obviously, the specific implementation mode described is only a part of the implementation mode of the present invention, rather than all styles.

[0035] The product structure of the slider 6 of the present invention is as follows Figure 5 As shown, it includes a metal part and a plastic part 62. The metal part has a through hole 61 for the rolling element to circulate and roll, and the plastic part 62 includes a silent pipe sleeve 621 that wraps the rolling element.

[0036] The present invention provides a mold structure for solving the problem of unsatisfactory injection molding of slender thin-walled parts during integral injection of a slider. Figures 1 to 4 As shown, it includes a movable mold base 1, a fixed mold plate 2, a lower mold core 4 and an upper mold core, the lower mold core 4 is embedded in the movable mold base 1, the upper mold core is embedded in the fixed mold plate 2, and the upper mold core and the lower mold core 4 are buckled together to form a cavity; it also includes a movable mold base plate 3 and a mold foot 7, the mold foot 7 is fixedly connected to the movable mold base plate 3, the movable mold base 1 is fixedly connected to the mold foot 7, a material stripping plate 8 is provided above the fixed mold plate 2 to strip the runner condensate, and a fixed mold base plate 9 is provided above the material stripping plate 8. When in use, the fixed mold base plate 9 is fixed to the injection molding machine.

[0037] like Figure 2 As shown, the lower mold core 4 is provided with a through hole inserting pin 5. Before closing the mold, the through hole inserting pin 5 is placed in the through hole 61, and then the lower mold core 4 is placed on the movable mold base 1 and fixedly connected.

[0038] like Figures 6-7As shown, the through-hole insert pin 5 is composed of a first insert pin 51 and a second insert pin 52. The first insert pin 51 is provided with a dovetail-shaped protrusion 511, and the second insert pin 52 is provided with a dovetail-shaped groove 523 corresponding to the protrusion 511. The first insert pin 51 and the second insert pin 52 are connected by the cooperation of the protrusion 511 and the groove 523. A gap is provided between the arc corners of the protrusion 511 and the groove 523, thereby forming an exhaust hole 53 that passes through from top to bottom. Six exhaust grooves 522 are provided on the joint surface 521 of the second insert pin 52. The exhaust grooves 522 are connected with the exhaust holes 53 to form an exhaust system. After the mold is closed, injection molding begins, and the melt flows into the cavity between the through-hole 61 and the through-hole insert pin 5. At this time, the air in the cavity is squeezed into the exhaust groove 522, and then discharged from the lower mold core 4 through the exhaust hole 53 connected with the exhaust groove 522. After cooling, a plastic part 62 with a silent pipe sleeve 621 is obtained.

[0039] When the melt enters the cavity formed by the through-hole insert 5 and the through-hole 61, it is necessary to ensure that the air can be discharged and that the melt does not enter the exhaust groove 522. Therefore, the depth of the exhaust groove 522 must be smaller than the overflow value of the melt. The melt overflow value used in the plastic part 62 of the present invention is 0.05 mm. At the same time, a margin must be left. Therefore, the depth of the exhaust groove 522 is set to 0.03 mm.

[0040] A method for solving the problem of unsatisfactory injection molding of slender thin-walled sliders during integral injection molding of the sliders of the present invention comprises the following steps:

[0041] S1: Fix the injection mold on the injection molding machine, and put the metal part of the integral injection slider 6 into the lower mold core 4;

[0042] S2: The injection mold is closed, and the melt is injected into the mold cavity. When the melt flows into the cavity between the through hole 61 of the metal part of the integral injection slider 6 and the through hole insert pin 5, the air in the cavity is squeezed into the exhaust groove 522, and then discharged from the lower mold core 4 through the exhaust hole 53 connected to the exhaust groove 522. Finally, the melt fills the entire mold cavity. After pressure holding and cooling, a complete plastic part 62 of the silent pipe sleeve 621 is formed;

[0043] S3: The injection mold is opened. The injection mold is first separated at the first parting surface 11. At this time, the plastic part 62 is separated from the runner condensate; then the injection mold is separated at the second parting surface 12. At this time, the material stripping plate 8 strips the runner condensate away; then the injection mold is separated at the third parting surface 13. Under the action of the injection molding machine, the ejector pin ejects the integral injection slider 6. At this time, one-shot injection molding is completed;

[0044] S4: The injection mold is closed to prepare for the next injection molding.

[0045] The above describes the main technical features and basic principles of the present invention and the related advantages. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the concept or basic features of the present invention. Therefore, no matter from which point of view, the above specific embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0046] In addition, it should be understood that although the present specification is described according to various implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation method may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A mold for solving the problem of slender thin-walled injection molding when a slider is integrally packaged, the slider comprising a metal part and a plastic part (62), the metal part having a through hole (61) for a rolling element to circulate, the plastic part (62) comprising a silent pipe sleeve (621) wrapping the rolling element, characterized in that: It comprises a movable mold base (1), a fixed mold plate (2), a lower mold core (4) embedded in the movable mold base (1) and an upper mold core embedded in the fixed mold plate (2), wherein the upper mold core and the lower mold core (4) are buckled together to form a mold cavity; The lower mold core (4) is provided with a through hole insert pin (5). Before closing the mold, the through hole insert pin (5) is placed in the through hole (61), and then the lower mold core (4) is placed on the movable mold base (1) and fixedly connected. The through hole insert pin (5) includes a first insert pin (51) and a second insert pin (52). The first insert pin (51) is provided with a protrusion (511), and the second insert pin (52) is provided with a groove (523) corresponding to the protrusion (511). The first insert pin (51) and the second insert pin (52) are connected by the matching of the protrusion (511) and the groove (523). A gap is provided between the protrusion (511) and the groove (523) to form an exhaust hole (53). The joint surface (521) of the second insert pin (52) is provided with a plurality of exhaust grooves (522). The exhaust grooves (522) are connected to the exhaust hole (53), and the shape of the protrusion (511) and the groove (523) is dovetail-shaped. The corners of the protrusion (511) and the groove (523) are arc-shaped; A gap is provided between the arc-shaped corner of the protrusion (511) and the arc-shaped corner of the groove (523), thereby forming an exhaust hole (53) that passes through from top to bottom; After the mold is closed, injection molding begins, and the melt flows into the cavity between the through hole (61) and the through hole insert pin (5). At this time, the air in the cavity is squeezed into the exhaust groove (522), and then discharged from the lower mold core (4) through the exhaust hole (53) connected to the exhaust groove (522). After cooling, a complete plastic part (62) of the silent pipe sleeve (621) can be obtained.

2. A mold for solving the problem of slender thin-walled injection molding when the slider is integrally packaged according to claim 1, characterized in that: The depth of the exhaust groove (522) is less than 0.05 mm.

3. A mold for solving the problem of slender thin-walled injection molding when the slider is integrally packaged according to claim 2, characterized in that: The depth of the exhaust groove (522) is 0.03 mm.

4. A mold for solving the problem of slender thin-walled injection molding when the slider is integrally packaged according to claim 1, characterized in that: The number of exhaust slots (522) is six.

5. A mold for solving the problem of slender thin-walled injection molding when the slider is integrally packaged according to claim 1, characterized in that: The mold also comprises a movable mold base plate (3) and a mold foot (7), wherein the mold foot (7) is fixedly connected to the movable mold base plate (3), the movable mold base (1) is fixedly connected to the mold foot (7), a material shifting plate (8) is arranged above the fixed mold plate (2), and a fixed mold base plate (9) is arranged above the material shifting plate (8).

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