CN113211728A

CN113211728A - Injection mold takes off back-off mechanism

Info

Publication number: CN113211728A
Application number: CN202110404947.9A
Authority: CN
Inventors: 李过; 林连明; 王永才
Original assignee: Zhejiang Kaihua Mould Co Ltd
Current assignee: Zhejiang Kaihua Mould Co Ltd
Priority date: 2021-04-15
Filing date: 2021-04-15
Publication date: 2021-08-06

Abstract

The invention discloses a reverse buckle removing mechanism of an injection mold, which comprises: a cavity; a core forming a space for an injection molded product with a cavity; a core-pulling element movable from a core-pulling and mold-locking position within the core to a core-pulling and mold-releasing position; the sliding block is connected to one end, far away from a product, of the core pulling piece in a sliding mode and can move from a sliding block mode locking position to a sliding block demolding position, so that the core pulling piece is driven to move from a core pulling mode locking position to a core pulling demolding position; and one end of the inclined wedge piece is fixed on the cavity, the other end of the inclined wedge piece extends inwards the sliding block and is matched with the inclined surface of the sliding block, and when the inclined wedge piece is separated from the sliding block, the inclined wedge piece drives the sliding block to move from the sliding block mold locking position to the sliding block mold releasing position. The invention ensures the strength of the die, simplifies the die structure, reduces the manufacturing cost of the die and improves the production efficiency.

Description

Injection mold takes off back-off mechanism

Technical Field

The invention relates to the technical field of molds, in particular to a reverse buckle removing mechanism of an injection mold.

Background

The removal of undercuts is often encountered in injection molding of large plastic articles. The product is inverted, and a structural part of the product with a reverse cladding die exists, so that the product cannot be directly and smoothly demoulded in one direction. Some working of plastics can be equipped with some kennels because the needs of assembly, are equipped with the mounting hole of indent at the kennels terminal surface, and what be common to this type of structure takes off the back-off structure is that the core is loosed the core or the little mould of core is opened. The core-pulling structure generally comprises two types, one type is that an inclined guide post and a sliding block are matched for core pulling, the structure is only suitable for the condition that the included angle between the surface where the mounting hole is located and the demolding direction is small, if the included angle is large, the strength of the mold core is insufficient, and the injection molding effect cannot be guaranteed; the other type of loose core drives a loose core sliding block through an oil cylinder, the loose core sliding block is separated from the inverted buckle along with the inverted pulling angle of the product, the product is separated, and the oil cylinder is used for loosing core, so that the cost of the die can be greatly increased. And in the small mold opening of the mold core, the mold core and a mold core backing plate are opened and blocked for a certain distance by using an external draw hook and an internal spring, so that a product is separated from the reverse buckle, the ejection of the product is completed, and a part is taken. This kind of structure mould mechanism is loaded down with trivial details, and the spring blocks fast easily, causes the mould to damage.

For example, a chinese patent document discloses "a structure of embedding an inclined guide post in a slider and an auxiliary device for processing the inclined guide post", whose publication No. CN210190444U includes a panel, an a plate and a B plate, the bottom of the panel is connected to the a plate by a screw, the a plate is provided with a clearance hole, the B plate is provided below the bottom of the a plate, the a plate is provided with an inclined guide post, the lower end of the inclined guide post penetrates through the slider, and the slider is opened by the inclined guide post when the mold is opened, and the slider is disposed on the B plate. The utility model discloses a through set up the slider in A board and B inboard, slide in the slider through oblique guide pillar, drive the slider drawing of patterns to the completion takes off the back-off. The utility model discloses a vertical setting of mounting hole place terminal surface, it is parallel with vertical drawing of patterns direction. The problem that the included angle between the inverted buckle removing end face and the demolding direction is small is solved, when the included angle is too large, the height of the sliding block needs to be increased in order to guarantee the inverted buckle removing, a deep groove or a deep hole needs to be formed in the mold to be used for installing the sliding block, the strength of the mold is reduced, and the service life of the mold is affected.

Disclosure of Invention

The invention provides the reverse-buckle removing mechanism of the injection mold, aiming at overcoming the problems of low strength, complexity in mechanism or low cost of the reverse-buckle removing structure of the mold in the prior art, ensuring the strength of the mold, simplifying the structure of the mold, reducing the manufacturing cost of the mold and improving the production efficiency.

In order to achieve the purpose, the invention adopts the following technical scheme:

an injection mold's mechanism of taking off back-off, includes:

a cavity;

a core forming a space for an injection molded product with a cavity;

a core-pulling element movable from a core-pulling and mold-locking position within the core to a core-pulling and mold-releasing position;

the sliding block is connected to one end, far away from a product, of the core pulling piece in a sliding mode and can move from a sliding block mode locking position to a sliding block demolding position, so that the core pulling piece is driven to move from a core pulling mode locking position to a core pulling demolding position;

and one end of the inclined wedge piece is fixed on the cavity, the other end of the inclined wedge piece extends inwards the sliding block and is matched with the inclined surface of the sliding block, and when the inclined wedge piece is separated from the sliding block, the inclined wedge piece drives the sliding block to move from the sliding block mold locking position to the sliding block mold releasing position.

The invention is characterized in that the combination of a wedge piece, a sliding block and a core pulling piece is used for releasing and reversing a product, wherein one end of the wedge piece is fixedly arranged on a cavity, the other end of the wedge piece is arranged in the sliding block under the matched die state of the cavity and a core, the sliding block is positioned at a mold locking position of the sliding block, the core pulling piece is positioned at a core pulling mold locking position, and the end part of the core pulling piece is abutted against the product; when the mold is opened, the mold cavity and the mold core are gradually separated, the mold cavity drives the wedge piece to gradually separate from the sliding block, the sliding block is driven to move from the mold locking position of the sliding block to the mold demolding position of the sliding block through the inclined surface matching of the wedge piece and the sliding block, so that the core pulling piece is driven to move from the mold locking position of the core pulling to the mold demolding position of the core pulling, the core pulling piece separates from a product, and the back-off is completed. According to the invention, the core-pulling part is released while the mold is opened, the inclination angle of the core-pulling part is determined according to the angle of the mounting hole, and the increase of the core-pulling angle does not affect the grooving depth of the core due to the fact that the wedge piece is arranged on the cavity and is transferred through the sliding block, so that the strength of the core is ensured. The invention has simple structure and reduces the manufacturing cost of the die.

Preferably, the sliding block is provided with a chute with an opening facing the inclined wedge piece, the opening end of the chute inclines towards the mold locking position of the sliding block, one end of the inclined wedge piece close to the sliding block is provided with an inclined wedge part, and the inclined wedge part is in inserted fit with the chute.

Under the die assembly state, the inclined wedge part is inserted in the chute, the die locking requirements of the sliding block and the core-pulling part are met, the condition that the inclined wedge part is separated from the chute after die opening and the sliding block is pushed to move away from the die locking position of the sliding block is met, the condition that a product is separated from an inverted buckle is met, and flash is reduced.

Preferably, the slopes of the two side walls of the chute are the same, and the slopes of the two side surfaces of the wedge portion corresponding to the side walls of the chute are the same.

The inclined wedge part is matched with an inclined plane of one side of the chute, which is close to the slide block mold locking position, during mold closing, the slide block is driven to the slide block mold locking position, the inclined wedge part is matched with an inclined plane of one side of the chute, which is close to the slide block demolding position, during mold opening, the slide block is driven to the slide block demolding position, the slopes of the two sides are consistent, the moving distance of the slide block is consistent during mold opening and mold closing, and the position of the slide block does not need to be adjusted in advance.

Preferably, a sliding groove is formed in the sliding block, and the core pulling member is connected with the sliding groove in a sliding mode.

When the sliding block slides, the sliding groove is driven to translate, so that the core pulling piece is driven to move axially. Preferably, the spout is T type groove, is equipped with on the loose core spare with T type groove notch sliding fit's U type groove, guarantees that the loose core spare is all driven by the slider and is removed along the spout extending direction when the mode locking and the drawing of patterns, guarantees the loose core spare and looses core smoothly and the mode locking dynamics.

Preferably, the slide block is arranged on one side of the core away from the cavity in a sliding mode, and the sliding direction of the slide block is perpendicular to the product demolding direction.

The product sets up between core and die cavity usually, and the slider setting is kept away from the one side of product promptly in the one side of die cavity is kept away from to the core, and the at utmost avoids influencing the intensity of core, mould, and slider moving direction makes the slider height unchangeable with product drawing of patterns direction is perpendicular simultaneously, and the core only needs to remove a small part structure and is used for installing the slider, guarantees core intensity and mould life-span.

Preferably, the slide is elastically connected to the core in the sliding direction.

The slider is guaranteed to accurately move to the slider demoulding position through elasticity, preferably, a pressure spring can be arranged in the slider, two ends of the pressure spring are respectively abutted to the slider and the core in a die assembly state, and the pressure spring assisting wedge piece pushes the slider to move in place after die opening is carried out, so that the core-pulling of the core-pulling piece is guaranteed to be in place.

Preferably, the mold core is provided with a limiting piece for limiting the sliding block at the sliding block demolding position.

The limiting part limits the demoulding position of the sliding block, the sliding block is guaranteed to move to the accurate demoulding position under the combined action of the wedge piece, the elastic piece and the limiting part, and the wedge piece can be accurately inserted into the chute when the die is closed next time.

Preferably, the chute wall is provided with a wear-resistant block.

The inclined wedge piece and the chute wall of the chute rub repeatedly, and the service life of the sliding block and the inclined wedge piece is prolonged by arranging the wear-resisting block.

Preferably, the core pulling piece is sleeved with a guide sliding sleeve, and the core pulling piece is arranged in the guide sliding sleeve in an axial sliding manner.

The friction force between the core pulling piece and the mold core is reduced, so that the core pulling piece slides smoothly, the abrasion is reduced, and the service life of the mold is prolonged.

Preferably, the inclined wedge portion comprises a plurality of inserting blocks, the inserting blocks are arranged along the depth direction of the inclined groove, adjacent inserting blocks are matched in an inserting mode, and an inserting groove used for being inserted into the inserting blocks is formed in the bottom of the inclined groove.

Through setting up a plurality of inserted blocks of arranging along the chute degree of depth direction, change the wedge length of sloping and the chute degree of depth simultaneously to change the displacement distance of slider and core piece, correspond the back-off structure of the different degree of depth of adaptation. For example, the insertion block at the end part of the wedge part is detached and inserted into the bottom of the chute, the length of the wedge part and the depth of the chute are reduced, and the moving distance of the wedge piece for pushing the sliding block is reduced, so that the moving distance of the core pulling piece is reduced, and the wedge type core pulling piece is suitable for a structure with a shallow mounting hole. The whole set of die does not need to be changed for mounting holes with different depths, so that the cost is reduced, and the efficiency is improved.

Therefore, the invention has the following beneficial effects: (1) through the arrangement of the cooperation of the wedge piece and the sliding block, the core pulling is completed while the mold is opened, and the core pulling angle range is wide; (2) the influence of the enlarged core-pulling angle on the strength of the die is greatly reduced, and the service life of the die is ensured; (3) the demolding is smooth, the mold locking force is large, and the product quality is high; (4) the moving distance of the slide block and the moving distance of the core-pulling piece are adjustable, the application range is wide, and the cost of the die is reduced; (5) the mold has simple structure and simple and convenient use and operation.

Drawings

Fig. 1 is a schematic structural view in a clamped state according to embodiment 1 of the present invention.

Fig. 2 is a schematic structural diagram of the mold opening state in embodiment 1 of the present invention.

FIG. 3 is a schematic view of a product of example 1 of the present invention in a mold-released state.

Fig. 4 is a schematic view of one construction of the core-pulling element, slider and cam member of the present invention.

Fig. 5 is a schematic structural diagram of embodiment 2 of the present invention.

Fig. 6 is a schematic structural diagram of an adjusted insert block according to embodiment 2 of the present invention.

In the figure: 1. the hot runner mold comprises a mold cavity, 11, a hot runner plate, 12, an upper web, 2, a mold core, 21, mold feet, 22, a lower web, 3, a core pulling part, 31, a guide sliding sleeve, 32, a U-shaped groove, 4, a sliding block, 41, a chute, 411, a slot, 42, a sliding groove, 43, a wear-resistant block, 44, a compression spring, 45, a pressing strip, 5, a wedge part, 51, a wedge part, 511, an insertion block, 52, an extension part, 6, a limiting part, 7, an upper ejector plate, 71, an ejector rod, 72, a lower ejector plate, 73, an ejector limiting block, 8, an injection molding part, 81 and a mounting hole.

Detailed Description

The invention is further described with reference to the following detailed description and accompanying drawings.

Example 1

As shown in fig. 1, 2, and 3, an undercut removing mechanism of an injection mold includes:

go up web 12 and lower web 22, go up web 12 below and connect hot runner plate 11, hot runner plate 11 below is connected with die cavity 1, is connected with mould foot 21 on the lower web 22, is connected with core 2 on the mould foot 21, forms the space that is used for injection moulding product between core 2 and the die cavity 1. An upper ejector plate 7 and a lower ejector plate 72 are arranged in a space between the mold core 2 and the lower web plate 22, an ejector rod 71 extends upwards from the upper ejector plate 7, the ejector rod 71 extends into the injection molding space, and an ejector limit block 73 protrudes from the upper ejector plate.

The core pulling piece is characterized by further comprising a core pulling piece 3, a sliding block 4, a wedge piece 5 and a limiting piece 6. The wedge member 5 has an elongated shape with a rectangular cross section, and includes an upper extending portion 52 and a lower wedge portion 51. The extension part 52 is vertically arranged, the top end of the extension part is fixed on the outer side of the cavity 1 through a bolt, the bottom end of the extension part is connected with the top end of the inclined wedge part 51 and forms an obtuse angle with the top end of the inclined wedge part 51, the inclined wedge part 51 inclines outwards of the mold, the slopes of the inner side and the outer side of the inclined wedge part 51 are consistent, and the top surface of the inner side of the inclined wedge part 51 is provided with a step surface. Because the wedge piece sets up in the mould outside, does not influence die cavity intensity, the mould size can suitably reduce.

As shown in FIG. 4, the slide block 4 is arranged at the bottom of the mold core 2 in a sliding manner, a groove for installing the slide block 4 is arranged on the outer side of the bottom of the mold core 2, and the inner side of the slide block 4 is arranged in the groove in a sliding manner. The top of the sliding block 4 is provided with a chute 41, the chute 41 is arranged outside the cavity 2 corresponding to the wedge part 51, the chute 41 is in insertion fit with the wedge part 51, the slopes of the two side walls of the chute 41 are consistent, and the chute 41 is connected with a wear-resistant block 43 through a screw on the side wall close to the mold core 2. The top of one side of the sliding block 4 close to the mold core 2 is provided with a sliding groove 42, the top end of the sliding groove 42 extends towards the direction of the wedge piece 5 in an inclined way, and the sliding groove 42 is a T-shaped groove. The bottom of the side, close to the mold core 2, of the sliding block 4 is provided with a spring groove, a pressure spring 44 is arranged in the spring groove, and the pressure spring 44 extends in the horizontal direction. Horizontal pressing strips 45 are arranged on two sides of the bottom of the sliding block 4, and the sliding block 4 is arranged between the pressing strips 45 in a sliding mode. The slider 4 outside is equipped with locating part 6, and locating part 6 is fixed on core 2. Because the slide block is arranged on the outer side of the bottom of the mold core, only a small part of structures are removed at the position, and the influence on the strength of the mold core is small.

As shown in fig. 4, the core pulling member 3 comprises two coaxial cylindrical structures, the diameter of the upper part is smaller than that of the lower part, U-shaped grooves 32 are arranged at two sides of the bottom end of the core pulling member 3, and the core pulling member 3 is slidably connected with the opening of the sliding groove 42 through the U-shaped grooves 32. The outside of the cylinder with larger diameter of the core pulling piece 3 is sleeved with a guide sliding bush 31. For the mounting holes 81 with different inclination angles, only the inclination angles of the core pulling piece and the sliding groove need to be changed, and the structure is suitable for demolding of reverse buckling structures with different inclination angles and does not affect the strength of the mold.

As shown in fig. 1, in a mold closing state, the tapered wedge portion 51 is inserted into the chute 41, a step surface of the tapered wedge portion 51 is attached to a top surface of the slider 4, the slider 4 is located at a slider mold locking position, two ends of the pressure spring 44 are respectively abutted to the core 2 and the slider and are in a compressed state, the core-pulling member 3 is located at a core-pulling mold locking position, one end of the core-pulling member 3 is arranged in the chute 42, and the other end of the core-pulling member passes through the core and is obliquely abutted to the bottom of the injection product 8. Under this state, the slider is locked by the slide wedge spare, and unable removal, the piece of loosing core guarantees the mode locking dynamics through the spout, reduces the product overlap.

After injection molding is completed, the cavity 1 is opened upwards, as shown in fig. 2, the cavity 1 drives the inclined wedge piece 5 to move upwards, the inclined wedge part 51 is gradually separated from the chute, the outer side surface of the inclined wedge part 51 is matched with the inclined surface of the chute wall outside the chute to push the sliding block 4 outwards, the sliding block is pushed outwards along the horizontal direction under the guiding action of the pressing strip 45 until the inclined wedge part is completely separated from the chute, the pressure spring gradually releases energy, the power-assisted sliding block moves in place, and after the sliding block moves to the sliding block demolding position, the limiting part 6 prevents the sliding block from continuing to move outwards, so that the chute is ensured to be opposite to the position below the inclined wedge part. After moving outwards, the sliding block 4 pulls the core pulling piece 3 downwards through the matching of the sliding groove 42 and the U-shaped groove 32, the bottom end of the core pulling piece 3 moves along the sliding groove 42, and the top end of the core pulling piece gradually breaks away from the inclined mounting hole 81 at the bottom of the product along the axial direction and moves to the core pulling and demolding position.

After the slide block and the core-pulling member are moved in place, the upper ejector plate 7 and the lower ejector plate 72 are lifted, the ejector rods 71 are driven to ascend, the injection-molded product is ejected from the core 2, and demolding is completed, as shown in fig. 3.

Example 2

As shown in fig. 5 and 6, a structure of a back-off mechanism of an injection mold is substantially the same as that of embodiment 1, except that a wedge part 51 includes a plurality of insertion blocks 511, and the insertion blocks 511 have a rectangular parallelepiped structure and include an end insertion block and a plurality of middle insertion blocks. One side of the end insertion block is provided with a dovetail convex strip, one side of the middle insertion block is provided with a dovetail convex strip, and the other side of the middle insertion block is provided with a dovetail groove. The insertion blocks 511 are arranged along the extending direction of the wedge part 51, namely the depth direction of the chute 41, the adjacent insertion blocks 511 are in inserted fit with the dovetail grooves through the dovetail convex strips, the bottom of the chute 41 is provided with an insertion slot 411 for being inserted with the insertion blocks 511, and the insertion slot 411 is a dovetail groove. The length of the wedge 51 and the depth of the chute 41 are modified by transferring the insert between the wedge 51 and the chute 41. As shown in fig. 5, two middle insertion blocks are inserted into the wedge portion, and an end insertion block is inserted into the outermost end, so that the wedge portion is in the longest state, and the chute 41 is in the deepest state. Deviate from tip inserted block from slide wedge portion, insert tip inserted block in 41 bottom slots 411 of chute, slide wedge portion length and chute degree of depth reduce in step, and slide wedge portion shortens with chute complex inclined plane under this state, and slide wedge portion slope is unchangeable, and slider horizontal migration distance shortens, and the axial displacement distance of loose core shortens, is applicable to the shallower product of mounting hole. More inserting blocks can be adjusted according to actual conditions to adjust the sliding distance. The insert block can be made of wear-resistant materials, and the service life of the wedge piece and the sliding block is prolonged. Only one set of mould just can adapt to the mounting hole of the different degree of depth, reduces mould cost.

Claims

1. The utility model provides an injection mold's taking off back-off mechanism which characterized by includes:

a cavity (1);

a core (2), wherein a space for an injection molding product is formed between the core (2) and the cavity (1);

a core-pulling element (3), wherein the core-pulling element (3) can move from a core-pulling and mold-locking position in the core (2) to a core-pulling and mold-releasing position;

the sliding block (4) is connected to one end, far away from a product, of the core pulling piece (3) in a sliding mode and can move from a sliding block mold locking position to a sliding block mold releasing position, and therefore the core pulling piece (3) is driven to move from a core pulling mold locking position to a core pulling mold releasing position;

and one end of the inclined wedge piece (5) is fixed on the cavity (1), the other end of the inclined wedge piece (5) extends into the sliding block (4) and is matched with the inclined surface of the sliding block (4), and when the inclined wedge piece (5) is separated from the sliding block (4), the inclined wedge piece (5) drives the sliding block (4) to move from the sliding block mold locking position to the sliding block mold releasing position.

2. The injection mold release mechanism according to claim 1, wherein the slide block (4) is provided with a chute (41) having an opening facing the wedge member (5), the opening end of the chute (41) is inclined toward the slide block locking position, one end of the wedge member (5) close to the slide block (4) is provided with a wedge portion (51), and the wedge portion (51) is in plug-in fit with the chute (41).

3. The injection mold release mechanism according to claim 2, wherein the slopes of the two side walls of the inclined groove (41) are the same, and the slopes of the two side walls of the inclined wedge portion (5) corresponding to the side walls of the inclined groove (41) are the same.

4. An injection mold release mechanism as claimed in claim 1, wherein the slide block (4) is provided with a slide groove (42), and the core pulling member (3) is slidably connected with the slide groove (42).

5. An injection mold undercut-removing mechanism as claimed in claim 1, wherein the slider (4) is slidably disposed on a side of the core (2) away from the cavity (1), and the sliding direction of the slider (4) is perpendicular to the product demolding direction.

6. An injection mould release mechanism according to claim 5, wherein the slide (4) is resiliently connected to the core (2) in the sliding direction.

7. The injection mold undercut removing mechanism of claim 5, wherein the core (2) is provided with a stopper (6) for stopping the slider (4) at the slider mold release position.

8. An injection mold release mechanism as claimed in claim 2, wherein said chute (41) has wear blocks (43) on its walls.

9. An injection mold undercut removing mechanism as claimed in claim 1, wherein said core pulling member (3) is sleeved with a sliding guide sleeve (31), and said core pulling member (3) is axially slidably disposed in the sliding guide sleeve (31).

10. The injection mold undercut removing mechanism of claim 2, wherein the wedge portion (51) comprises a plurality of insertion blocks (511), the insertion blocks (511) are arranged along a depth direction of the inclined groove (41), adjacent insertion blocks (511) are inserted and matched, and a slot (411) for inserting the insertion block (511) is formed in the bottom of the inclined groove (41).