CN108044881B

CN108044881B - Valve needle mounting device for mold

Info

Publication number: CN108044881B
Application number: CN201810038540.7A
Authority: CN
Inventors: 李象烈
Original assignee: Yudo Suzhou Hot Runner Systems Co Ltd
Current assignee: Yudo Suzhou Hot Runner Systems Co Ltd
Priority date: 2018-01-16
Filing date: 2018-01-16
Publication date: 2021-03-02
Anticipated expiration: 2038-01-16
Also published as: CN108044881A

Abstract

The invention discloses a valve needle mounting device for a mold, which comprises a piston, a valve needle hanging table arranged on the piston and a valve needle arranged on the valve needle hanging table, wherein the valve needle extends along a longitudinal axis, the piston is provided with a containing groove, the valve needle hanging table is completely contained in the containing groove, the valve needle is fixed relative to the piston in the extending direction of the longitudinal axis, the valve needle can move relative to the piston in a first direction, and the first direction is perpendicular to the extending direction of the longitudinal axis. The valve needle mounting device not only avoids the damage of the valve needle, but also has compact structure and smaller volume, and the thickness of the corresponding mould of the valve needle mounting device is smaller.

Description

Valve needle mounting device for mold

Technical Field

The invention relates to the field of hot runner injection molding, in particular to a valve needle mounting device for a mold in a hot runner injection molding system.

Background

Hot runners are a collection of heating assemblies used in injection molds to inject molten plastic into the cavity of the mold. Generally, hot runner systems are classified into open type hot runner systems and valve pin type hot runner systems. Including needle mounting structure in the valve needle formula hot runner system, at present, needle mounting structure includes components such as piston, needle installed part, needle usually, and the needle passes the flow distribution plate installation, and at the in-process of moulding plastics, the temperature of flow distribution plate is very high, and the flow distribution plate is heated when expanding, can lead to needle slope, atress wearing and tearing and card dead, and serious can lead to collapsing absolutely.

In order to solve the above problems, the skilled person has conducted studies. The valve needle is provided to be slidable, but the mounting structure between the valve needle and the piston is located outside the piston, so that the structure is complicated and the length in the axial direction of the valve needle is long, thereby making the thickness of the template thick.

Disclosure of Invention

The invention aims to provide a valve needle mounting device which not only avoids the damage of a valve needle, but also has compact structure, smaller volume and smaller thickness of a corresponding mould.

In order to achieve one of the above objects, the present invention provides a needle mounting device for a mold, the needle mounting device including a piston, a needle mounting table provided on the piston, and a needle provided on the needle mounting table, the needle extending along a longitudinal axis, wherein the piston is provided with a receiving groove, the needle mounting table is completely received in the receiving groove, the needle is fixed relative to the piston in an extending direction of the longitudinal axis, the needles are movable relative to the piston in a first direction, and the first direction is perpendicular to the extending direction of the longitudinal axis.

As a further improvement of an embodiment of the present invention, the valve needle is movably disposed on the valve needle hanging table along a first direction, the valve needle hanging table is movably disposed on the piston along a second direction, the second direction is perpendicular to an extending direction of the longitudinal axis, and an included angle is formed between the second direction and the first direction.

As a further improvement of an embodiment of the present invention, the second direction is perpendicular to the first direction.

As a further improvement of an embodiment of the present invention, an adapter groove extending along a first direction is provided on the needle hanging table, and the needle is movably provided in the adapter groove along the first direction.

As a further improvement of an embodiment of the present invention, an opening portion and a stopper portion are provided at the mating engagement groove, and the needle is provided with a bayonet portion that is mated with the stopper portion to restrict movement of the needle in an extending direction of the longitudinal axis and to allow the needle to move in the first direction.

As a further improvement of an embodiment of the present invention, the receiving groove has a square cross section in a direction perpendicular to the longitudinal axis, the receiving groove has a first pair of sides and a second pair of sides parallel to each other, the needle hanging platform has two side portions substantially parallel to the first pair of sides and two end portions abutting against the second pair of sides, respectively, and a distance between the two side portions is smaller than a distance between the first pair of sides so that the needle hanging platform is movable relative to the piston.

As a further improvement of an embodiment of the present invention, the two end portions and the second pair of side edges are in surface contact with each other, and connecting portions between the two end portions and the two side edges are both provided in an arc shape.

As a further improvement of an embodiment of the present invention, the needle mounting device further includes a stopper piece provided at an end portion of the accommodation groove to restrict movement of the needle hanging table in an extending direction of the longitudinal axis with respect to the piston.

As a further improvement of an embodiment of the present invention, an annular groove is provided on the piston and adjacent to the stopper piece, and the needle mounting device further includes a snap spring that is engaged with the annular groove.

As a further improvement of an embodiment of the present invention, the stopper piece is fixedly attached to the piston by a screw.

Compared with the prior art, the invention has the beneficial effects that: the valve pin mounting arrangement of the present invention is provided on the mould in separate units, in the required number and location. According to the valve needle mounting device, the valve needle hanging table is completely accommodated in the accommodating groove of the piston, so that the structure is compact, the size is small, in addition, the size of the valve needle mounting device in the direction of the longitudinal axis is small, the thickness of a mold for mounting the valve needle mounting device is small, and the manufacturing cost is further reduced. Moreover, the valve needle is set to be movable in the first direction relative to the piston, and when the flow distribution plate is heated and expanded, the valve needle can be moved adaptively, so that the influence caused by thermal expansion is eliminated, and the damage conditions such as stress abrasion, blocking or breakage of the valve needle are avoided.

Drawings

FIG. 1 is a schematic perspective view of a valve needle mounting apparatus according to an embodiment of the present invention;

figure 2 is an exploded perspective view of the valve needle mounting arrangement of figure 1;

figure 3 is a front view of the valve needle mounting arrangement of figure 1;

figure 4 is a bottom view of the valve needle mounting arrangement of figure 1;

figure 5 is a bottom view of the valve needle mounting arrangement of figure 1 with the stop and snap spring removed;

figure 6 is a top view of the valve needle mounting arrangement of figure 1;

FIG. 7 is a cross-sectional view A-A of FIG. 6;

fig. 8 is a sectional view taken along line B-B of fig. 6.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.

In addition, it will be understood that, although the terms first, second, etc. may be used herein to describe various elements or structures, these described elements should not be limited by the above terms. The above terms are only used to distinguish these descriptive objects from each other. For example, a first pair of sides may be referred to as a second pair of sides, and likewise, a second pair of sides may also be referred to as a first pair of sides without departing from the scope of the application.

The preferred embodiment of the present invention discloses a mold, which comprises a mold plate (not shown), a driving device (not shown) and a valve pin mounting device 100 (see fig. 1), wherein the valve pin mounting device 100 is arranged on the mold plate. As shown in fig. 1 to 2, the valve needle mounting device 100 includes a piston 10, a valve needle hanging table 12 disposed on the piston 10, and a valve needle 14 disposed on the valve needle hanging table 12, the valve needle 14 extends along a longitudinal axis 18, and a driving device drives the piston 10 to drive the valve needle 14 to move along an extending direction of the longitudinal axis 18, so that a fluid passage is separated from or communicated with a mold cavity.

In addition, the valve pin mounting device 100 is a unitary device that can be mounted directly on a reserved location of a mold as an integral assembly or as a separate unit. The valve pin 14 is provided with a flow distribution plate (not shown) at its outer periphery, and the valve pin 14 is inserted into a center hole communicating with a mold cavity (not shown), the center hole having an inner diameter larger than an outer diameter of the valve pin 14, so that a gap is provided between the center hole and the valve pin 14, which forms a fluid passage.

In particular in the present preferred embodiment, with further reference to fig. 2 to 8, the piston 10 is provided with a receiving groove 16, the needle mounting 12 is completely received in the receiving groove 16, the needle 14 is fixed relative to the piston 10 in the extension direction of the longitudinal axis 18, the needle 14 is movable relative to the piston 10 in a first direction, which is perpendicular to the extension direction of the longitudinal axis 18.

The needle mounting device 100 of the present embodiment is provided on the mold in separate units in the required number and positions. In addition, the needle hanging table 12 is completely accommodated in the accommodating groove 16 of the piston 10, so that the structure is compact and the volume is small, and in addition, the dimension of the needle mounting device 100 in the direction of the longitudinal axis 18 is small, so that the thickness of a mold for mounting the needle mounting device 100 is small, and the manufacturing cost is further reduced. Furthermore, the valve needle 14 is arranged to be movable relative to the piston 10 in the first direction, and when the flow distribution plate expands due to heat, the valve needle 14 can move adaptively, so that the influence caused by the thermal expansion is eliminated, and the damage conditions such as forced abrasion, seizure or breakage of the valve needle 14 are avoided.

In particular, the driving device may be configured as an air cylinder, or may be configured as an electric cylinder or an oil cylinder, as long as the piston 10 can be driven to move the valve needle 14 along the longitudinal axis 18.

Further, the needle 14 is movably disposed on the needle hanging platform 12 along a first direction, and the needle hanging platform 12 is movably disposed on the piston 10 along a second direction, which is perpendicular to the extending direction of the longitudinal axis 18 and forms an included angle with the first direction. Specifically, in the present embodiment, the second direction is perpendicular to the first direction. When the splitter plate is heated to expand in the injection molding process, because the expansion direction is uncertain, the influence caused by the expansion is eliminated through the sliding of the valve needle hanging table 12 and the valve needle 14 in two directions, and in addition, the valve needle 14 can move back and forth in two directions which are at right angles relative to the piston 10, so that the occurrence of faults such as the breakage of the valve needle 14 is greatly reduced. Of course, other angles between the second direction and the first direction may be provided.

Specifically, the needle hanging table 12 is provided with an adapter groove 20 extending along a first direction, and the needle 14 is movably provided on the adapter groove 20 along the first direction. The mating notch 20 has an opening 22 and a stop 24, and the needle 14 has a notch 26, and the notch 26 is mated with the stop 24 to limit the movement of the needle 14 in the extending direction of the longitudinal axis 18 and allow the needle 14 to move in the first direction. The opening 22 is used to facilitate mounting of the valve needle 14 to the mating groove 20. Of course, other connection means between the needle 14 and the needle hanging platform 12 may be adopted as long as the needle 14 is fixed relative to the needle hanging platform 12 in the extending direction of the longitudinal axis 18 and the needle 14 is movable relative to the needle hanging platform 12 in the first direction.

The piston 10 includes a body portion 28 and a mounting portion 30, the mounting portion 30 being generally cylindrical in shape about an outer periphery, the mounting portion 30 having an axis 31. The housing groove 16 is provided in the mounting portion 30, the housing groove 16 has a square cross section in a direction perpendicular to the longitudinal axis 18, the housing groove 16 has a first pair of sides 32 and a second pair of sides 34 parallel to each other, the needle hanging platform 12 has two side portions 36 substantially parallel to the first pair of sides 32 and two end portions 38 respectively abutting against the second pair of sides 34, and a distance between the two side portions 36 is smaller than a distance between the first pair of sides 32, so that the needle hanging platform 12 is movable in the second direction with respect to the piston 10. In the preferred embodiment, the range of movement of the valve needle 14 relative to the needle rest 12 in the first direction is from approximately 3mm from one side of the axis 31 to approximately 3mm from the other side of the axis 31. Of course, the range of movement may be set to other distances.

The housing grooves 16 are provided symmetrically with respect to the axial line 31 of the mounting portion 30. The sum of the distances between the two side parts 36 of the valve needle hanging table 12 and the first pair of side edges 32 is 6mm, that is, when the valve needle 14 is positioned at the position where the longitudinal axis 18 of the valve needle 14 coincides with the axis 31 of the mounting part 30, the distance between one side part of the valve needle hanging table 12 and one first side edge 32 is 3mm, and the distance between the other side part of the valve needle hanging table 12 and the other first side edge 32 is also 3 mm. Of course, the sum of the distances between the two side portions 36 of the needle hanging platform 12 and the first pair of side edges 32 can be set to other distances.

The end portions 38 and the second pair of sides 34 are in surface contact with each other, so that the movement of the needle 14 relative to the needle hanging platform 12 is more stable and reliable. In addition, the connecting portions between the two end portions 38 and the two side portions 36 are each provided in an arc shape. The arc transition prevents stress concentration and enhances the strength of the needle hanging platform 12.

The needle mounting device 100 further includes a stopper piece 40 provided at an end portion of the accommodation groove 16 to restrict movement of the needle hanging platform 12 relative to the piston 10 in an extending direction of the longitudinal axis 18. Thereby reliably and stably fixing the needle hanging table 12 to the piston 10. Specifically, the stopper piece 40 is fixedly connected to the piston 10 by two screws 42, so that the needle hanging platform 12 is fixed relative to the piston 10 in the extending direction of the longitudinal axis 18. Of course, other fixing means can be used to fix the stop piece 40 to the piston 10, such as riveting or the like.

Further, an annular clamping groove 44 is formed on the piston 10 and adjacent to the stop piece 40, and the valve needle mounting device 100 further includes a clamping spring 46 clamped with the annular clamping groove 44. When the screw 42 is loosened after a long time of movement, the snap spring 46 can ensure that the stop piece 40 can still be reliably and stably fixed to the piston 10, so that the valve needle mounting device 100 provided by the embodiment is more reliable.

Next, the assembling steps of the valve needle mounting apparatus 100 in this embodiment will be specifically described, and the assembling steps specifically include:

1. clamping a clamping opening part 26 on the valve needle 14 on a stopping part 24 of the valve needle hanging table 12 from the opening part 22;

2. placing the needle hanging platform 12 in the receiving groove 16 of the piston 10, and enabling the two end parts 38 to be in contact with the second opposite side edges 34 of the receiving groove 16;

3. the stop piece 40 is fixed at the end of the containing groove 16 by two screws 42 to limit the drop of the valve needle hanging table 12;

4. the snap spring 46 is clamped in the annular clamping groove 44, so that reliable fixation of the valve needle hanging table 12 is further ensured.

Finally, the valve pin mounting device 100 is assembled, i.e., the valve pin mounting device 100 is mounted on the mold plate of the mold as a whole.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.

Claims

1. A needle installation device for a mold, the needle installation device comprises a piston, a needle hanging table arranged on the piston and a needle arranged on the needle hanging table, the needle extends along a longitudinal axis, the needle installation device is characterized in that the piston is provided with an accommodating groove, the needle hanging table is completely accommodated in the accommodating groove, the needle is immovable relative to the piston in the extending direction of the longitudinal axis, the needle is movable relative to the piston in a first direction, the first direction is perpendicular to the extending direction of the longitudinal axis, the accommodating groove is provided with a first opposite side and a second opposite side which are parallel to each other, a plane which passes through the longitudinal axis and is perpendicular to the first opposite side is a first plane, a clamping groove which extends along the first direction is arranged on the needle hanging table and is matched with the clamping groove, the valve needle is movably arranged in the adapting clamping groove along a first direction, an opening part and a stopping part are arranged at the adapting clamping groove, the valve needle is provided with a clamping opening part, the clamping opening part is matched and connected with the stopping part so as to limit the valve needle to move in the extending direction of a longitudinal axis and allow the valve needle to move along the first direction, the projection of the adapting clamping groove and the clamping opening part on the first plane is completely positioned in the projection range of the outer peripheral part of the valve needle hanging table opposite to the periphery of the accommodating groove on the first plane, and the valve needle partially extends into the accommodating groove in the extending direction of the longitudinal axis.

2. The needle mounting arrangement of claim 1 wherein the needle is movably disposed on the needle mount in a first direction, the needle mount is movably disposed on the piston in a second direction, the second direction is perpendicular to the direction of extension of the longitudinal axis, and the second direction is at an angle to the first direction.

3. A valve needle mounting arrangement as claimed in claim 2 wherein the second direction is mutually perpendicular to the first direction.

4. The needle mounting device according to claim 1, wherein the receiving groove has a square cross section in a direction perpendicular to the longitudinal axis, the needle hanging platform has two side portions substantially parallel to the first pair of side edges and two end portions abutting against the second pair of side edges, respectively, and a distance between the two side portions is smaller than a distance between the first pair of side edges so that the needle hanging platform is movable relative to the piston.

5. The valve needle mounting device of claim 4 wherein the two end portions and the second pair of side edges are in surface contact with each other, and the connecting portions between the two end portions and the two side edges are arc-shaped.

6. The needle mounting arrangement of claim 1 further comprising a stop tab disposed at an end of the pocket to limit movement of the needle hanging platform relative to the piston in the direction of extension of the longitudinal axis.

7. The needle mounting arrangement of claim 6 wherein an annular detent is provided on the piston adjacent the stop tab, the arrangement further comprising a snap spring for engaging the annular detent.

8. A valve needle mounting arrangement as claimed in claim 6 wherein the stop plate is fixedly attached to the piston by means of screws.