A bijective mold transformable rear mold structure and a bijective mold

Abstract

The present invention discloses a transformable rear mold structure for a bi-injection mold and a bi-injection mold. The transformable rear mold structure includes a rear mold and a transformation unit; the transformation unit includes a floating plate vertically and slidably mounted on the rear mold core of the rear mold, two opposite sliding members slidably mounted on the rear mold core, a driving member for driving the sliding members to move, and an elastic support member clamped between the floating plate and the rear mold core; lifting control portions are provided on one side of each of the two sliding members facing each other; a first wavy structure is provided on the lifting control portion, and a second wavy structure is provided on the floating plate; when the crests and troughs of the two wavy structures face each other, the floating plate can be in a descending state during the first-shot mold closing; when the crests of the two wavy structures abut against each other, the floating plate is in an ascending state during the second-shot. The bi-injection mold includes a first-shot front mold, a second-shot front mold, and two transformable rear mold structures. The present invention can make the rear mold structure present two different states, and is applicable to occasions where the rear mold structures of the first-shot and second-shot of some injection molded products are inconsistent.

Description

Technical Field

[0001] The present invention belongs to the technical field of molds, and particularly relates to a transformable rear mold structure for a two-shot mold and a two-shot mold. Background Art

[0002] With the rapid development of the consumer electronics industry, the injection molding process requirements for plastic molds have been increasing year by year, and the development of two-shot injection molds has become more and more common. A two-shot mold is a mold in which two plastic materials are injection molded on the same injection molding machine, and are formed in two shots, namely the first shot and the second shot, but the product is demolded only once.

[0003] At present, the shapes of the two front molds used for the first-shot and second-shot molding of the vast majority of two-shot molds are different, while the structures of the two rear molds are completely the same and cannot be flexibly transformed according to needs; therefore, it cannot be applied to some occasions where the rear mold structures of the first-shot and second-shot of injection molded products are inconsistent, which limits the molding of some special injection molded products. Summary of the Invention

[0004] Aiming at overcoming the problems existing in the above-mentioned prior art, the present invention provides a transformable rear mold structure for a two-shot mold and a two-shot mold, which can make the rear mold structure present two different states during the first-shot and second-shot molding, and is applicable to some occasions where the rear mold structures of the first-shot and second-shot of injection molded products are inconsistent.

[0005] To solve the problems existing in the above-mentioned prior art, an embodiment of the present invention provides a transformable rear mold structure for a two-shot mold, including a rear mold and a transformation unit; the rear mold includes a rear mold core, and the transformation unit includes a floating plate vertically and slidably installed on the rear mold core, two sliding members oppositely and horizontally slidably installed on the rear mold core, a driving member for driving the two sliding members to move relatively or away from each other, and an elastic support member clamped between the floating plate and the rear mold core; lifting control portions are respectively formed on one side of the two sliding members facing each other, and the lifting control portions extend into the bottom of the floating plate; the upper surface of the lifting control portion has a first wavy structure, and the lower surface of the floating plate has a second wavy structure adapted to the first wavy structure;

[0006] When the peak of the first wavy structure is vertically opposite to the valley of the second wavy structure, the floating plate can be transformed into a descending state during the first-shot mold closing; when the peak of the first wavy structure abuts against the peak of the second wavy structure, the floating plate is transformed into an ascending state during the second shot.

[0007] Further, two sets of positioning ball components corresponding to the sliding members one by one are installed on the rear mold core;

[0008] At least two positioning grooves are arranged at intervals along the sliding direction on the lower surface of each lifting control portion, and the positioning grooves extend along the direction perpendicular to the sliding direction and are adapted to be clamped with the positioning ball components.

[0009] Further, the sliding member includes a body located outside the floating plate. A lifting control portion extending along the sliding direction is formed in the middle of one side of the body; a through inclined guide groove is provided on the body, and the inclined guide groove extends from the top end to the bottom end in a direction away from the floating plate.

[0010] The driving member at least includes two bent pins corresponding to the sliding member one by one, and the bent pins are in inclined surface fit with the inclined guide groove.

[0011] Further, an arc-shaped positioning groove is provided on the body. The arc-shaped positioning groove and the lifting control portion are on the same side of the body and the arc-shaped positioning groove is above the lifting control portion; an arc-shaped protrusion adapted to the arc-shaped positioning groove is provided on the side of the floating plate.

[0012] Further, the rear mold further includes an insert installed on the rear mold core; an insert avoidance hole is provided on the floating plate, and an arc-shaped avoidance opening adapted to the outer peripheral surface of the insert is provided on the lifting control portion.

[0013] Further, the rear mold core includes a base. A groove penetrating along the sliding direction is provided on the base. A convex platform is provided at the bottom of the groove, and an insert positioning groove is provided on the convex platform; positioning notch openings adapted to the ends of the floating plate are respectively provided on the bases on opposite sides of the groove; the elastic support member is arranged in the positioning notch openings.

[0014] Further, a T-shaped slide rail and a driving avoidance groove are respectively provided at the bottom of the groove on both sides of the convex platform, and a T-shaped slide groove adapted to the T-shaped slide rail is provided at the bottom of the sliding member.

[0015] Further, guide columns are respectively installed on the bases corresponding to the two positioning notch openings; one end of the guide column extends into the corresponding positioning notch opening and is slidably connected with the floating plate.

[0016] Further, a limit baffle structure is provided on the base on one side of the positioning notch opening, and the limit baffle structure is used for limiting the ascending floating plate; and the limiting portion of the limit baffle structure extends into the positioning notch opening.

[0017] A limit notch opening adapted to the limiting portion is provided on the floating plate.

[0018] To solve the problems existing in the above-mentioned prior art, an embodiment of the present invention further provides a double-shot mold, including a first-shot front mold, a second-shot front mold, and two double-shot mold transformable rear mold structures as described above; the driving member is detachably installed on the second-shot front mold.

[0019] Due to the adoption of the above technical solution, the beneficial effects obtained are as follows:

[0020] In the bi-injection mold transformable rear mold structure of the present invention, it includes a rear mold and a transformation unit; the rear mold includes a rear mold core, and the transformation unit includes a floating plate vertically and slidably mounted on the rear mold core, two opposite sliding members horizontally and slidably mounted on the rear mold core, a driving member for driving the two sliding members to move relatively or away from each other, and an elastic support member clamped between the floating plate and the rear mold core; on the opposite sides of the two sliding members, lifting control parts are respectively formed, and the lifting control parts extend into the bottom of the floating plate; the upper surface of the lifting control part has a first wavy structure, and the lower surface of the floating plate has a second wavy structure adapted to the first wavy structure; when the wave crest of the first wavy structure is vertically opposite to the wave trough of the second wavy structure, the floating plate can be transformed into a descending state during the first-shot mold closing; when the wave crest of the first wavy structure abuts against the wave crest of the second wavy structure, the floating plate is transformed into a second-shot ascending state. The bi-injection mold includes a first-shot front mold, a second-shot front mold, and two bi-injection mold transformable rear mold structures; the driving member is detachably mounted on the second-shot front mold.

[0021] During the first-shot molding process, the two sliding members are in their respective first locking positions. At this time, the wave crest of the first wavy structure is vertically opposite to the wave trough of the second wavy structure, and the elastic support member provides floating support for the floating plate. When the mold is closed, under the impact force F of the first-shot front mold, the floating plate can be transformed into a first-shot descending state (at this time, the wave crest and the wave trough are in contact); during the second-shot molding process, when the mold is closed, under the drive of the driving member on the second-shot front mold, the two sliding members move relatively. When they are in their respective second locking positions, the wave crest of the first wavy structure abuts against the wave crest of the second wavy structure, and the floating plate is transformed into a second-shot ascending state.

[0022] In summary, the present invention can make the rear mold structure present two different states during the first-shot and second-shot molding processes, which is applicable to occasions where the rear mold structures of the first-shot and second-shot of some injection products are inconsistent; it overcomes the problem of limited injection products existing in the existing bi-injection molds. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of the bi-injection mold variable rear mold structure of the present invention during the second-shot molding;

[0024] Figure 2 is Figure 1 the structural exploded view of;

[0025] Figure 3 is Figure 2 a schematic structural diagram of the floating plate in another perspective in;

[0026] Figure 4 is Figure 1 the top view of;

[0027] Figure 5 is Figure 4 the sectional view taken along line A-A in

[0028] Figure 6 is Figure 5 the enlarged view of the structure at position C in

[0029] Figure 7 is Figure 4 the sectional view taken along line B-B in

[0030] Figure 8 is the top view of the structure of the variable rear mold structure of the double-shot mold of the present invention during the first-shot molding

[0031] Figure 9 is Figure 8 the sectional view taken along line D-D in

[0032] Figure 10 is Figure 9 the enlarged view of the structure at position E in

[0033] In the figure: 1 - rear mold core, 11 - base, 12 - groove, 13 - boss, 131 - insert positioning groove, 14 - positioning groove opening, 15 - T-shaped slide rail, 16 - driving avoidance groove, 2 - sliding part, 21 - body, 211 - inclined guide groove, 212 - arc-shaped positioning groove, 213 - T-shaped chute, 22 - lifting control part, 221 - first wavy structure, 222 - positioning groove, 223 - arc-shaped avoidance opening, 3 - floating plate, 31 - second wavy structure, 32 - arc-shaped protrusion, 33 - insert avoidance hole, 34 - linear bearing, 35 - limit groove opening, 4 - bent pin, 41 - fixing part, 42 - driving part, 5 - elastic support member, 6 - positioning ball, 7 - insert, 8 - guide post, 9 - limit baffle structure. Detailed implementation manners

[0034] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0035] By Figures 1 to 10As shown together, this embodiment discloses a transformable rear mold structure for a bi-injection mold, including a rear mold and a transformation unit; the rear mold includes a rear mold core 1, and the transformation unit includes a floating plate 3 vertically and slidably mounted on the rear mold core 1, two opposite sliding members 2 horizontally and slidably mounted on the rear mold core 1, a driving member for driving the two sliding members 2 to move relatively or away from each other, and an elastic support member 5 clamped between the floating plate 3 and the rear mold core 1; the elastic support member 5 is used to provide elastic support that makes the floating plate 3 tend to move upward. On the opposite sides of the two sliding members 2, lifting control portions 22 are respectively formed, and the lifting control portions 22 extend between the floating plate 3 and the rear mold core 1; the upper surface of the lifting control portion 22 has a first wavy structure 221, and the lower surface of the floating plate 3 has a second wavy structure 31 adapted to the first wavy structure 221. When the two sliding members 2 are in their respective first locking positions and the peaks of the first wavy structure 221 are opposite to the valleys of the second wavy structure 31 (supported by the elastic support member 5, at this time the peaks and valleys are only vertically aligned and do not abut temporarily), the floating plate 3 can be transformed into a descending state during the first-shot mold closing (during mold closing, under the impact force F of the first-shot front mold core, the floating plate 3 overcomes the elastic force of the elastic support member 5 and descends, and at this time the peaks and valleys abut). When the two sliding members 2 are in their respective second locking positions and the peaks of the first wavy structure 221 abut against the peaks of the second wavy structure 31, the floating plate 3 is transformed into a second-shot ascending state.

[0036] Among them, the first wavy structure 221 includes a plurality of first trapezoidal convex portions (extending along a direction perpendicular to the sliding direction) arranged at equal intervals on the upper surface of the lifting control portion 22 along the sliding direction, and a first trapezoidal concave portion is formed between adjacent two first trapezoidal protrusions. The second wavy structure 31 includes a plurality of second trapezoidal convex portions (extending along a direction perpendicular to the sliding direction) arranged at equal intervals on the lower surface of the floating plate 3 along the sliding direction, and a second trapezoidal concave portion is formed between adjacent two second trapezoidal protrusions.

[0037] In this embodiment, the rear mold core 1 includes a base 11, on which a groove 12 is provided that passes through in the sliding direction, a boss 13 is provided in the middle of the bottom of the groove 12, and an insert positioning groove 131 is provided on the boss 13; the base 11 on opposite sides of the groove 12 is provided with positioning notches 14 that match the ends of the floating plate 3; elastic support members 5 (preferably cylindrical springs) are arranged in the positioning notches 14 (in this embodiment, two elastic support members 5 are arranged in each positioning notch 14 at intervals in the sliding direction). The insert 7 is installed in the insert positioning groove 131; the floating plate 3 is provided with an insert avoidance hole 33 for the insert 7 to extend out, and the lifting control part 22 is provided with an arc-shaped avoidance opening 223 that matches the outer peripheral surface of the insert 7. In order to prevent abnormal deformation of the elastic support member 5 when bearing load, the present embodiment further optimizes the above structure, a first accommodating groove is provided at the bottom of the positioning notch 14, a second accommodating groove is provided at the bottom of the floating plate 3, one end of the elastic support member 5 is located in the first accommodating groove, and the other end is located in the second accommodating groove.

[0038] In order to ensure that the sliding member 2 can be fixed in the first locking position or the second locking position to keep the position unchanged after moving to the right position; the present embodiment further optimizes the above structure, and two sets of positioning bead assemblies corresponding to the sliding member 2 are installed on the rear mold core 1 (preferably the boss 13); the lower surface of each lifting control part 22 is provided with at least two arc-shaped positioning grooves 222 (two positioning grooves 222 are shown in the figure) at intervals along the sliding direction, and the positioning grooves 222 extend along the vertical sliding direction and are adapted to the positioning bead assembly. Each set of positioning bead assemblies includes two positioning beads 6 arranged along the vertical sliding direction. Among them, the positioning bead 6 includes a mounting seat, and the mounting seat is provided with a mounting cavity, and the mounting cavity is sequentially installed with a spring and a ball from bottom to top. The cooperation between the positioning bead 6 and the positioning groove 222 can ensure that the sliding member 2 does not slide when subjected to the impact force F in the vertical sliding direction, and remains in the current locking position, thereby accurately controlling the position of the floating plate 3.

[0039] In this embodiment, the sliding member 2 includes a body 21 located outside the floating plate 3, and a lifting control part 22 extending along the sliding direction is formed in the middle of one side of the body 21; two through-going oblique guide grooves 211 are arranged at intervals on the body 21, and the oblique guide grooves 211 extend from the top to the bottom in the direction away from the floating plate 3; the driving member includes four bent pins 4, one sliding member 2 corresponds to two bent pins 4, and the driving part 42 of the bent pin 4 is matched with the corresponding oblique guide groove 211 in an inclined plane, and the fixing part 41 of the bent pin 4 can be detachably installed on the second shot front mold. Due to the inclined plane matching, the four bent pins 4 can force the two sliding members 2 to move relative to each other when moving vertically downward, and can force the two sliding members 2 to move away from each other when moving vertically upward.

[0040] In order to precisely control the sliding stroke of the sliding member 2, in this embodiment, an arc-shaped positioning groove 212 is provided on the body 21. The arc-shaped positioning groove 212 and the lifting control portion 22 are located on the same side of the body 21, and the arc-shaped positioning groove 212 is located above the lifting control portion 22; an arc-shaped protrusion 32 adapted to the arc-shaped positioning groove 212 is provided on the side of the floating plate 3.

[0041] In order to ensure the stable reliability of the sliding of the sliding member, this embodiment further optimizes the above structure. T-shaped slide rails 15 and two driving avoidance grooves 16 respectively adapted to the ends of two bent pins 4 are provided on the bottom of the grooves 12 on both sides of the convex platform 13. A T-shaped chute 213 adapted to the T-shaped slide rail 15 is provided at the bottom of the body 21 in the sliding member 2; the T-shaped chute 213 is located between two inclined chutes 211.

[0042] In order to further ensure the stable reliability during the lifting process of the floating plate 3, this embodiment further optimizes the above structure. Two guiding columns 8 respectively penetrate through the bottom of the base 11 corresponding to the two positioning notch openings 14; one end of the guiding column 8 extends into the corresponding positioning notch opening 14 and is slidably and cooperatively connected with a linear bearing 34 (or a guide sleeve) on the floating plate 3. In addition, in order to precisely control the rising amplitude of the floating plate 3, this embodiment makes a further optimization. A limit baffle structure 9 is provided on the base 11 on one side of the positioning notch opening 14. The limit baffle structure 9 is used to limit the rising floating plate 3; and the limiting portion of the limit baffle structure 9 horizontally extends into the positioning notch opening 14 perpendicular to the sliding direction and is located above the floating plate 3; a limiting notch opening 35 adapted to the limiting portion is provided on the floating plate 3.

[0043] This embodiment also discloses a double-shot mold, including a first-shot front mold, a second-shot front mold, and two above-mentioned double-shot mold convertible rear mold structures; the bent pin 4 is detachably installed on the second-shot front mold; another bent pin structure is not installed or installed on the first-shot front mold, and this bent pin structure does not generate a driving force on the sliding member 2 when the mold is closed.

[0044] The working principle is briefly described below based on the above structure:

[0045] First-shot molding process: Before the first-shot front mold is closed, the two sliding members 2 are in their respective corresponding first locking positions (the cooperation between the positioning ball 6 and the positioning groove 222 on the sliding member 2 far from the body 21 can ensure that when impacted by a force F perpendicular to the sliding direction, the sliding member 2 does not slide and remains in the current locking position. See Figure 10), at this time, the peak of the first wavy structure 221 is aligned with the trough of the second wavy structure 31, and the elastic support 5 floatingly supports the floating plate 3; when the mold is closed, under the impact force F of the first-shot front mold, the floating plate 3 descends against the elastic force of the elastic support 5 and transforms into the first-shot descending state. At this time, the sliding member 2 remains in its current position unchanged, and the peak of the first wavy structure 221 abuts against the trough of the second wavy structure 31 (see Figure 9 ).

[0046] During the second-shot molding process, before the second-shot front mold is closed, the floating plate 3 is in the initial state under the floating support of the elastic support 5 (after the mold is opened after the first shot is completed, the floating plate 3 has returned to the initial state under the elastic force of the elastic support 5); when the mold is closed, the angled pins 4 on the second-shot front mold drive the two sliding members 2 to move relative to each other until they reach their respective second locking positions (the cooperation between the positioning beads 6 and the positioning grooves 222 on the sliding members 2 close to the body 21 can ensure that when impacted by a force F perpendicular to the sliding direction, the sliding member 2 does not slide and remains in the current locking position, see Figure 6 ). At this time, the peak of the first wavy structure 221 abuts against the peak of the second wavy structure 31, and the floating plate 3 rises and transforms into the second-shot rising state (see Figure 5 ); after the two-shot injection molding is completed, when the mold is opened, the angled pins 4 on the second-shot front mold drive the two sliding members 2 to move away from each other. After the mold opening is completed, the sliding members 2 are in the first locking position, waiting to cooperate with the first-shot front mold for the first-shot molding of the next product.

[0047] The two-shot mold uses the first-shot front mold, the second-shot front mold, and the two transformable rear mold structures of the two-shot mold to achieve the alternating and continuous molding of the first shot and the second shot; the specific molding process is well-known to those skilled in the art and will not be elaborated here one by one.

[0048] In summary, the present invention can make the rear mold structure present two different states during the first-shot and second-shot molding, which is suitable for some occasions where the rear mold structures of the first-shot and second-shot of injection products are inconsistent; it overcomes the problem of limited injection products existing in the existing two-shot molds.

[0049] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bijective mold transformable rear mold structure, characterized in that, It includes a rear mold and a transformation unit; the rear mold includes a rear mold core, and the transformation unit includes a floating plate vertically and slidably mounted on the rear mold core, two sliding members oppositely and horizontally slidably mounted on the rear mold core, a driving member for driving the two sliding members to move relatively or away from each other, and an elastic support member clamped between the floating plate and the rear mold core; on the opposite sides of the two sliding members, lifting control parts are respectively formed, and the lifting control parts extend into the bottom of the floating plate; the upper surface of the lifting control part has a first wavy structure, and the lower surface of the floating plate has a second wavy structure adapted to the first wavy structure; When the wave crest of the first wavy structure is vertically opposite to the wave trough of the second wavy structure, the floating plate can be transformed into a descending state during the first injection mold closing; when the wave crest of the first wavy structure abuts against the wave crest of the second wavy structure, the floating plate is transformed into an ascending state during the second injection; Two sets of positioning ball components corresponding to the sliding members one by one are mounted on the rear mold core; On the lower surface of each lifting control part, at least two positioning grooves are arranged at intervals along the sliding direction, and the positioning grooves extend along the direction perpendicular to the sliding direction and are adapted to be clamped with the positioning ball components.

2. The bijective mold transformable rear mold structure according to claim 1, wherein The sliding member includes a main body located outside the floating plate, and the lifting control part extending along the sliding direction is formed in the middle of one side of the main body; an inclined guide groove is formed through the main body, and the inclined guide groove extends from the top end to the bottom end in a direction away from the floating plate; The driving member at least includes two bent pins corresponding to the sliding members one by one, and the bent pins are in inclined surface fit with the inclined guide grooves.

3. The bijective mold transformable rear mold structure according to claim 2, characterized in that, An arc-shaped positioning groove is formed on the main body, and the arc-shaped positioning groove is on the same side of the main body as the lifting control part and above the lifting control part; an arc-shaped protrusion adapted to the arc-shaped positioning groove is arranged on the side of the floating plate.

4. The bijective mold transformable rear mold structure according to claim 1, wherein, The rear mold further includes an insert mounted on the rear mold core; an insert avoidance hole is arranged on the floating plate, and an arc-shaped avoidance opening adapted to the outer peripheral surface of the insert is arranged on the lifting control part.

5. The bijective mold transformable rear mold structure according to any one of claims 1 to 4, characterized in that, The rear mold core includes a base, a groove penetrating along the sliding direction is formed on the base, a convex platform is arranged at the bottom of the groove, and an insert positioning groove is formed on the convex platform; positioning notch openings adapted to the ends of the floating plate are respectively arranged on the bases on the opposite sides of the groove; the elastic support member is arranged in the positioning notch openings.

6. The bijective mold transformable rear mold structure according to claim 5, characterized in that T-shaped slide rails and driving avoidance grooves are respectively arranged at the bottom of the groove on both sides of the convex platform, and a T-shaped slide groove adapted to the T-shaped slide rail is arranged at the bottom of the sliding member.

7. The bijective mold transformable rear mold structure according to claim 5, characterized in that, Guide columns are respectively mounted on the bases corresponding to the two positioning notch openings; one end of the guide column extends into the corresponding positioning notch opening and is in sliding fit connection with the floating plate.

8. The bijective mold transformable rear mold structure according to claim 5, characterized in that A limit baffle structure is arranged on the base on one side of the positioning notch opening, and the limit baffle structure is used for limiting the ascending floating plate; and the limiting part of the limit baffle structure extends into the positioning notch opening; A limit notch opening adapted to the limiting part is arranged on the floating plate.

9. A bijective mold, characterized in that, It includes a first injection front mold, a second injection front mold, and a transformable rear mold structure of a double-injection mold as described in any one of claims 1-8; the driving member is detachably mounted on the second injection front mold.

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