CN113276353B

CN113276353B - Injection mold

Info

Publication number: CN113276353B
Application number: CN202110566578.3A
Authority: CN
Inventors: 孙连伟; 李旦; 章芬
Original assignee: Jiangxi Lianyi Optics Co Ltd
Current assignee: Jiangxi Lianyi Optics Co Ltd
Priority date: 2021-05-24
Filing date: 2021-05-24
Publication date: 2023-01-03
Anticipated expiration: 2041-05-24
Also published as: CN113276353A

Abstract

The invention provides an injection mold, which comprises an upper runner plate, a lower runner plate and a cavity insert which are sequentially arranged along the mold closing direction, wherein the lower runner plate and the cavity insert are locked by locking pieces, and the upper runner plate is opened and closed relative to the lower runner plate; a lower runner plate insert is movably arranged in the lower runner plate, a cavity insert movable insert is movably arranged in the cavity insert, and the lower runner plate insert and the cavity insert are locked by a locking piece; the lower runner plate insert is internally provided with a second elastic piece, one end of the second elastic piece abuts against the lower runner plate insert, and the other end of the second elastic piece abuts against the cavity insert, so that the power part of the lower runner plate insert extends out of the end face of the lower runner plate. The invention can omit the female die pressing plate by optimizing the existing female die anti-sticking die structure, can simultaneously meet the characteristics of avoiding sticking the female die and automatically ejecting the plastic product for the plastic product, and avoids the problems of lengthening the runner and increasing the thickness of the female die plate to cause the increase of the manufacturing cost of raw materials and the die due to the existence of the female die pressing plate.

Description

Injection mold

Technical Field

The invention belongs to the technical field of plastic product molding, and particularly relates to an injection mold.

Background

Most plastic products are formed by plastic mold injection molding, and are generally applied to electronic products, communication products, consumer products and the like. In recent years, plastic molds have been the subject of extensive research and development with the widespread use of electronic products, communication products, and consumer products. In the production process of the plastic product, aiming at the plastic product which has large side size of a female die, small die drawing angle, larger packing force of an insert and needs to adopt glue dripping, after the plastic product is subjected to injection molding, in the die opening process, the plastic product is extremely easy to stick a female die and even completely stays on the insert at the side of the female die, so that the molded plastic product can not be smoothly taken out.

At present, aiming at the problem that the plastic products of the types are difficult to smoothly take out after injection molding and mold opening in the market, a female mold anti-sticking mold structure is developed, and as shown in fig. 1 to 4 in detail, the mold structure comprises a female mold core 30, a female mold core fixing insert 32, a female mold core movable insert 31, a first elastic piece 23, a second elastic piece 22, a T-shaped ejector rod 33, a lower runner plate 20 and an upper runner plate 10; in addition, a female mold platen 40 is additionally arranged between the lower runner plate 20 and the female mold core 30, the female mold core movable insert 31 is locked with the female mold platen 40, and the lower runner plate 20 is locked with the female mold platen 40. Specifically, the first elastic member 23 is installed in the female mold platen 40, the second elastic member 22 passes through the female mold platen 40, and both ends of the second elastic member abut against the lower runner plate 20 and the female mold insert 30, respectively, the female mold insert movable insert 31 and the T-shaped ejector pin 33 are movably installed in the female mold insert fixed insert 32, and the female mold insert fixed insert 32 is installed in the female mold insert 30. In the specific movement process, under the action of the second elastic pieces 22, the lower runner plate 20, the female die pressing plate 40 and the female die core movable insert 31 move backwards together, so that the female die core movable insert 31 is pulled out, and the plastic product 50 is prevented from being adhered to the female die; and the plastic product 50 is ejected out through the T-shaped ejector rod 33 under the action of the first elastic member 23. However, in the above-mentioned female mold anti-sticking structure, the length of the runner is increased by adding the female mold platen 40, which inevitably reduces the utilization rate of raw materials and increases the cost of raw materials; both of them require an increase in the thickness of the master plate, which inevitably leads to an increase in the cost of the mold and the cost of processing, and an increase in the cost of manufacturing the mold.

Disclosure of Invention

In order to solve the technical problems, the invention provides an injection mold, which is characterized in that the structure of the existing female mold anti-sticking mold is optimized to save a female mold pressing plate, so that the problems of raw material and mold manufacturing cost increase caused by the lengthening of a flow channel and the increase of the thickness of the female mold plate due to the existence of the female mold pressing plate are solved.

The invention provides the following technical scheme, an injection mold is applied to the injection mold and comprises an upper runner plate, a lower runner plate and a cavity insert which are sequentially arranged along the mold closing direction, wherein the lower runner plate and the cavity insert are locked through locking parts, and the upper runner plate is opened and closed relative to the lower runner plate;

a lower runner plate insert is movably arranged in the lower runner plate, a cavity insert movable insert is movably arranged in the cavity insert, and the lower runner plate insert and the cavity insert movable insert are locked by a locking piece; a second elastic piece is arranged in the lower runner plate insert, one end of the second elastic piece abuts against the lower runner plate insert, and the other end of the second elastic piece abuts against the cavity insert, so that the power part of the lower runner plate insert extends out of the end face of the lower runner plate; when the die is closed, the upper runner plate approaches the lower runner plate, the lower runner plate insert is pressed into the lower runner plate by the upper runner plate through the power part, the cavity insert movable insert is driven to be pressed into the cavity insert and the core insert is closed to form a plastic product, and at the moment, the second elastic piece is in a compressed state; when the mold is opened, the upper runner plate is far away from the lower runner plate, the second elastic piece automatically recovers to drive the lower runner plate insert to drive the cavity insert movable insert to move relative to the cavity insert, so that the cavity insert movable insert is drawn out of the plastic product.

Compared with the prior art, the invention has the beneficial effects that: the lower runner plate is locked with the cavity insert through the locking piece, and the lower runner plate insert is movably arranged in the lower runner plate through the second elastic piece, so that the cavity insert locked with the lower runner plate insert is automatically drawn out of a plastic product formed during mold closing when the mold is opened, and the effect of preventing the plastic product from being stuck on a female mold is achieved as the effect of an existing female mold anti-sticking mold structure with a female mold pressing plate; the invention saves the female die pressing plate, thereby shortening the injection runner, saving the raw materials required by injection molding, ensuring good molding quality of the plastic product, reducing the required thickness of the female die plate and lowering the material cost and the processing cost of the die.

Preferably, the lower runner plate is provided with a lower runner plate through hole for the lower runner plate insert to be inserted through, a first limit sinking groove is dug in the end surface of the lower runner plate facing one side of the cavity insert, and the first limit sinking groove is communicated with the lower runner plate through hole; the first limiting part of the lower runner plate insert is accommodated in the first limiting sinking groove, and the height of the first limiting part is smaller than the depth of the first limiting sinking groove. The technical characteristic design aims to ensure that the lower runner plate insert moves in a moving space defined by the lower runner plate so as to control the moving range of the cavity insert.

Preferably, the cavity insert is provided with a cavity insert through hole, a cavity insert fixing insert with a middle opening is tightly matched in the cavity insert through hole, and the cavity insert movable insert is inserted into the cavity insert fixing insert and moves relative to the cavity insert fixing insert; the technical characteristic design aims to prevent the movable insert of the cavity insert from directly contacting with the cavity insert.

Preferably, the female die core fixing insert is provided with a fixing insert through hole for inserting the T-shaped ejector rod, and a second limiting sinking groove is dug on the end surface of the female die core fixing insert facing one side of the lower runner plate and communicated with the fixing insert through hole; the second limiting part of the T-shaped ejector rod is accommodated in the second limiting sinking groove, and the height of the second limiting part is smaller than the depth of the second limiting sinking groove. The technical characteristic design aims to enable the T-shaped ejector rod to move in a moving space limited by the cavity insert so as to control the distance of the T-shaped ejector rod for ejecting the plastic product.

Preferably, the lower runner plate is provided with a first elastic element facing the cavity insert, the first elastic element corresponds to the second limiting sinking groove, one end of the first elastic element abuts against the lower runner plate, and the other end of the first elastic element abuts against the end of the T-shaped ejector rod, so that the ejection part of the T-shaped ejector rod extends out of the end face of the cavity insert; when the die is closed, the ejection part is extruded by the male die core and retracted into the female die core, and the first elastic piece is in a compressed state; when the mold is opened, the first elastic piece automatically recovers to drive the ejection part to extend out of the cavity insert, so that the T-shaped ejector rod ejects the molded plastic product.

Preferably, the height of the T-shaped ejector rod is not more than the thickness of the cavity insert. The technical characteristic design aims at preventing a gap between the lower runner plate and the cavity core after the lower runner plate and the cavity core are locked, and preventing plastic fluid from leaking at the gap.

Preferably, the first elastic member and the second elastic member are both springs.

Preferably, the limited compression amount of the second elastic member is not greater than the limited compression amount of the first elastic member. The technical characteristic design aims to ensure that the movable insert of the female die core is completely extracted from the plastic product when the die is opened, thereby ensuring that the plastic product is smoothly taken out.

Preferably, the cavity insert and the cavity insert fixing insert are tightly fitted in an interference fit manner. The technical characteristic design aims to ensure the firmness of the two assembled parts and the convenient disassembly and replacement of the female die core fixing insert.

Preferably, the height of the lower runner plate insert is not greater than the thickness of the lower runner plate. The technical characteristic design aims to prevent the plastic fluid from leaking at the gap when the upper runner plate and the lower runner plate are closed.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a perspective view of a prior art anti-sticking mold structure for a female mold of an injection mold;

FIG. 2 is a front view of a prior art anti-sticking mold structure for a master mold of an injection mold;

FIG. 3 isbase:Sub>A cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 2;

FIG. 5 is a perspective view of an injection mold (when closed) according to an embodiment of the present invention;

FIG. 6 is a perspective view of an injection mold (when the mold is opened) according to an embodiment of the present invention;

FIG. 7 is a front view of an injection mold provided in accordance with an embodiment of the present invention;

FIG. 8 is a cross-sectional view taken along line D-D of FIG. 7 (when the mold is closed);

FIG. 9 is a cross-sectional view taken in the direction D-D of FIG. 7 (when the mold is open);

fig. 10 is a schematic view of the position of the lower runner plate insert and the cavity insert fixing insert according to the embodiment of the present invention;

FIG. 11 is a perspective view of a lower flow field plate provided in accordance with an embodiment of the present invention;

FIG. 12 is a cross-sectional view in the direction C-C of FIG. 7 (when the mold is closed);

FIG. 13 is a cross-sectional view taken along line C-C of FIG. 7 (with the mold open);

FIG. 14 is an enlarged partial view of section E of FIG. 13;

description of reference numerals:

10-an upper runner plate;

20-lower runner plate, 201-lower runner plate perforation, 202-first limit sink, 21-lower runner plate insert, 211-power part, 212-first limit part, 22-second elastic part, 23-first elastic part;

30-a cavity insert, 301-a cavity insert through hole, 31-a cavity insert movable insert, 32-a cavity insert fixed insert, 321-a fixed insert through hole, 322-a second limit sinking groove, 33-T-shaped ejector rods, 331-a second limit part and 332-an ejector part;

40-a female mold platen;

50-plastic products.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the embodiments of the present invention, and should not be construed as limiting the invention.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. Specific meanings of the above terms in the embodiments of the present invention may be understood by those of ordinary skill in the art according to specific situations.

In an embodiment of the present invention, as shown in fig. 5 and fig. 6, it should be noted that the injection mold further includes components such as a core plate, a core insert, and a cavity plate, but the components do not belong to the technical point to be protected by the present invention, and therefore, the description thereof is omitted. The injection mold includes an upper flow field plate 10, a lower flow field plate 20, and a cavity insert 30 sequentially arranged along a mold closing direction. In this embodiment, the lower runner plate 20 and the cavity insert 30 are locked by the locking members, and the upper runner plate 10 is opened and closed relative to the lower runner plate 20. Specifically, compared to the conventional master mold anti-sticking mold structure shown in fig. 1, in which the upper runner plate 10 serves as a movable body, the lower runner plate 20 and the master mold platen 40 serve as a movable body, and the cavity insert 30 serves as a movable body, the comparison between the upper runner plate 10 of the present invention serving as a movable body and the lower runner plate 20 and the cavity insert 30 serving as a movable body shows that: the invention can reduce the probability of leakage of plastic fluid from the gap of the movable body during injection molding and can improve the injection molding efficiency.

As shown in fig. 7, 8, 9 and 10, a lower runner plate insert 21 is movably disposed in the lower runner plate 20, a cavity insert 31 is movably disposed in the cavity 30, and the lower runner plate insert 21 and the cavity insert 31 are locked by a locking member. In this embodiment, the locking member is a bolt, and the bolt passes through the cavity insert movable insert 31 and is in threaded connection with the lower runner plate insert 21, so that the lower runner plate insert 21 and the cavity insert movable insert 31 are firmly connected. Further, the height of the lower flow field plate insert 21 is not greater than the thickness of the lower flow field plate 20, in order to prevent the plastic fluid from leaking from the gap between the upper flow field plate 10 and the lower flow field plate 20 when the lower flow field plate insert 21 is fully pressed by the upper flow field plate 10 during mold clamping.

Further, a second elastic member 22 is disposed in the lower runner plate insert 21, and preferably, the second elastic member 22 is a spring. In this embodiment, one end of the second elastic member 22 abuts against the lower runner plate insert 21, and the other end abuts against the cavity insert 30, so that the power portion 211 of the lower runner plate insert 21 extends out of the end surface of the lower runner plate 20. In a specific operation process, in a mold closing process, the upper runner plate 10 approaches the lower runner plate 20, the upper runner plate 10 presses the lower runner plate insert 21 into the lower runner plate 20 through the power part 211, so as to drive the cavity insert movable insert 31 to be pressed into the cavity 30 and the core insert to close the mold to form the plastic product 50, and at this time, the second elastic member 22 is in a compressed state; during the mold opening process, the upper runner plate 10 is far away from the lower runner plate 20, and the second elastic element 22 automatically recovers to drive the lower runner plate insert 21 to extend out of the lower runner plate 20 towards one side of the upper runner plate 10, and at the same time, drive the cavity insert movable insert 31 to move towards one side of the lower runner plate 20 relative to the cavity insert 30, so that the cavity insert movable insert 31 is extracted from the plastic product 50. The invention enables the cavity insert movable insert 31 locked with the lower runner plate insert 21 to be automatically drawn out from the plastic product 50 formed in the mold closing process during the mold opening process, thereby achieving the same effect as the existing female mold anti-sticking mold structure with the female mold press plate 40 in preventing the plastic product from sticking the female mold; the invention omits the female die pressing plate 40, thereby shortening the injection runner, saving the raw materials required by injection molding, having good molding quality of plastic products, reducing the required thickness of the female die plate and lowering the material cost and the processing cost of the die.

As shown in fig. 11, the lower runner plate 20 is provided with a lower runner plate through hole 201 through which the lower runner plate insert 21 is inserted, a first limit sunken groove 202 is dug in an end surface of the lower runner plate 20 facing the cavity insert 30, and the first limit sunken groove 202 is communicated with the lower runner plate through hole 201. In this embodiment, as shown in fig. 10, the first limiting portion 212 of the lower runner plate insert 21 is received in the first limiting recessed groove 202. Specifically, the lower flow field plate insert 21 passes through the lower flow field plate 20 from the side close to the cavity insert 30 through the lower flow field plate through hole 201, and is restrained by the first restraining portion 212 and the first restraining groove 202, so that the lower flow field plate insert 21 is prevented from passing through the lower flow field plate through hole 201.

Further, the height of the first limiting portion 212 is smaller than the depth of the first limiting sinking groove 202, so that the lower runner plate insert 21 can move in the moving space defined by the lower runner plate 20, so as to control the moving distance of the cavity insert 31 relative to the cavity insert 30.

As shown in fig. 12, 13 and 14, the cavity insert 30 is provided with a cavity insert through hole 301, and the cavity insert through hole 301 is tightly fitted with a cavity insert fixing insert 32 having a central opening. In this embodiment, the cavity insert movable insert 31 is inserted into the cavity fixing insert 32 and moves relative to the cavity fixing insert 32, so as to prevent the cavity insert movable insert 31 from directly contacting the cavity 30, thereby preventing the surface of the cavity 30 and the cavity insert movable insert 31 from being worn. Specifically, because the cavity insert movable insert 31 moves relative to the cavity insert fixed insert 32, a direct contact friction condition exists between the two, and in order to facilitate convenient replacement of the worn cavity insert fixed insert 32, the cavity insert 30 and the cavity insert fixed insert 32 are tightly fitted in an interference fit manner, so that the cavity insert fixed insert 32 can be conveniently detached and replaced, and the firmness of the assembled cavity insert fixed insert 32 and the cavity insert 30 is ensured.

Further, the cavity insert fixing insert 32 is provided with a fixing insert through hole 321 for inserting the T-shaped push rod 33. In this embodiment, a second limiting sinking groove 322 is dug on an end surface of the cavity insert fixing insert 32 facing one side of the lower runner plate 20, the second limiting sinking groove 322 is communicated with the fixing insert through hole 321, and the second limiting portion 331 of the T-shaped ejector rod 33 is accommodated in the second limiting sinking groove 322. Specifically, the T-shaped top bar 33 passes through the cavity insert fixing insert 32 from the side close to the lower flow channel plate 20 through the fixing insert through hole 321, and is prevented from passing through the fixing insert through hole 321 by the second limiting portion 331 under the limitation of the second limiting sinking groove 322. The height of the T-shaped ejector rod 33 is not greater than the thickness of the cavity insert 30, and the purpose is to prevent a gap from being left between the lower runner plate 20 and the cavity insert 30 after the lower runner plate and the cavity insert 30 are locked together during mold closing, thereby preventing plastic fluid from leaking at the gap.

Further, the height of the second limiting portion 331 is smaller than the depth of the second limiting sunken groove 322, so that the T-shaped top bar 33 can move in the moving space defined by the cavity insert 30 to control the distance of the T-shaped top bar 33 ejecting the plastic product.

Further, a first elastic piece 23 is accommodated on one side of the lower runner plate 20 facing the cavity insert 30, and the first elastic piece 23 corresponds to the second limiting sinking groove 322; preferably, the first elastic members 23 are all springs. In this embodiment, one end of the first elastic element 23 abuts against the lower runner plate 20, and the other end abuts against the end of the T-shaped top bar 33, so that the ejecting portion of the T-shaped top bar 33 extends out of the end surface of the cavity insert 30. In a specific operation process, in a mold closing process, the ejector 332 is extruded and retracted into the cavity insert 30 through the core insert, and at this time, the first elastic member 23 is in a compressed state; in the mold opening process, the first elastic member 23 automatically recovers to drive the ejection portion 332 to extend out of the cavity insert 30, so that the T-shaped ejector rod 33 automatically ejects the molded plastic product. According to the invention, through the arrangement of the first elastic part 23 and the second elastic part 22, the characteristics that the plastic product is prevented from being adhered to a female die and can be automatically ejected are met. Preferably, the limited compression amount of the second elastic member 22 is not greater than the limited compression amount of the first elastic member 23, so that the cavity insert movable insert 31 is completely pulled out of the plastic product when the mold is opened, thereby ensuring smooth removal of the plastic product.

It should be noted that the structure of the present invention can be processed in addition to the conventional anti-sticking structure of the female mold of the injection mold shown in fig. 1 because: in the original design, the movable insert 31 of the cavity insert is not designed to be drawn out first to prevent the product from sticking to the cavity mold, and if the existing anti-sticking structure of the cavity mold of the injection mold shown in fig. 1 is adopted, the cavity mold plate may have no space and is difficult to be processed; if the structure of the invention is adopted, the following processing can be directly carried out, the processing cost of die transformation is reduced, and the structure is convenient and quick.

The above description is intended to be illustrative of the preferred embodiment of the present invention and should not be taken as limiting the invention, but rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Claims

1. An injection mold is characterized by comprising an upper runner plate, a lower runner plate and a cavity insert which are sequentially arranged along a mold closing direction, wherein the lower runner plate and the cavity insert are locked through locking pieces, and the upper runner plate is opened and closed relative to the lower runner plate;

the lower runner plate is movably provided with a lower runner plate insert, the cavity insert is movably provided with a cavity insert movable insert, and the lower runner plate insert and the cavity insert are locked by a locking piece; a second elastic piece is arranged in the lower runner plate insert, one end of the second elastic piece abuts against the lower runner plate insert, and the other end of the second elastic piece abuts against the female die core, so that the power part of the lower runner plate insert extends out of the end face of the lower runner plate; the female die core is provided with a female die core through hole, a female die core fixing insert with a middle opening is tightly matched in the female die core through hole, and the female die core movable insert is inserted into the female die core fixing insert and moves relative to the female die core fixing insert; the female die core fixing insert is provided with a fixing insert through hole for the T-shaped ejector rod to penetrate through, and the end face of the female die core fixing insert facing one side of the lower runner plate is provided with a second limiting sinking groove in an excavating mode; the lower runner plate is provided with a first elastic piece facing the cavity insert, the first elastic piece corresponds to the second limit sinking groove, one end of the first elastic piece abuts against the lower runner plate, and the other end of the first elastic piece abuts against the end part of the T-shaped ejector rod, so that the ejection part of the T-shaped ejector rod extends out of the end surface of the cavity insert; when the die is closed, the upper runner plate approaches to the lower runner plate, the lower runner plate insert is pressed into the lower runner plate by the upper runner plate through the power part, the cavity insert movable insert is driven to be pressed into the cavity insert and the core insert is closed to form a plastic product, the second elastic piece is in a compression state, the ejection part is extruded by the core insert and retracted into the cavity insert, and the first elastic piece is in a compression state; when the mold is opened, the upper runner plate is far away from the lower runner plate, the second elastic piece automatically recovers to drive the lower runner plate insert to extend out of the lower runner plate towards one side of the upper runner plate so as to drive the cavity insert movable insert to move relative to the cavity towards one side of the lower runner plate, so that the cavity insert movable insert is extracted from a plastic product; the first elastic piece automatically recovers to drive the ejection part to extend out of the female die core, so that the T-shaped ejector rod ejects the molded plastic product.

2. The injection mold according to claim 1, wherein the lower runner plate is provided with a lower runner plate through hole for inserting the lower runner plate insert, the end surface of the lower runner plate facing the cavity core is provided with a first limit sink groove, and the first limit sink groove is communicated with the lower runner plate through hole; the first limiting part of the lower runner plate insert is accommodated in the first limiting sinking groove, and the height of the first limiting part is smaller than the depth of the first limiting sinking groove.

3. The injection mold of claim 1, wherein the second limiting sink is in communication with the fixing insert through hole; the second limiting part of the T-shaped ejector rod is accommodated in the second limiting sinking groove, and the height of the second limiting part is smaller than the depth of the second limiting sinking groove.

4. The injection mold of claim 1, wherein the height of the T-shaped ejector pin is not greater than the thickness of the cavity insert.

5. An injection mold according to claim 1, wherein the first and second elastic members are both springs.

6. An injection mold as claimed in claim 5, wherein the limited compression of said second resilient member is no greater than the limited compression of said first resilient member.

7. The injection mold of claim 1, wherein the cavity insert and the cavity insert fixing insert are tightly fitted in an interference fit manner.

8. An injection mold according to any one of claims 1-7, wherein the height of the lower runner plate insert is no greater than the thickness of the lower runner plate.