DE19542102B4 - Tool for multi-component injection molding - Google Patents

Abstract

Tool (1) for multi-component injection molding of plastic brush bodies (2) for toothbrushes or the like, wherein the brush body (2) partially from several successively molded components (2a, 2b) and wherein the injection mold (3) at least from an ejector side mold plate ( 4) and a nozzle-side, fixed mold plate (5), each of which first mold nests (6a) for spraying the base body (2a) and second mold nests (6b) for overmolding the base body (2a) or for pre-spraying the brush body (2) in which the basic bodies (2a) are transported from the first mold cavities (6a) to the second mold cavities (6b), characterized in that
- The first and the second mold cavities (6a, 6b) are arranged pointing with their brush head areas (7) in the same direction,
- in each case at the first and at the second mold cavities (6a, 6b) of the ejector side mold plate (4) transverse members (13, 14) for holding the brush body (2) in the mold cavity portion (18) for the brush head regions (7) are arranged,
- in the mold plate (4) in the mold cavity section ...

Description

The The invention relates to a tool for multi-component injection molding of Plastic brush bodies for toothbrushes according to the preamble of claim 1.

It are already injection molding machines with a turning tool for spraying of several components existing brushes, For example, two-tone toothbrushes, known.

In these, a basic body is first injected, which remains after this injection process in the part of the mold half in which no changes are made. After this first injection process, the tool holding the base body is rotated by 180 degrees, for example, and the main body is then fed to a second injection process. In this second injection process is then carried out, for example, a partial encapsulation of the body so that the end product, for example, a two- or multi-colored toothbrush body is formed. From the DE 91 03 553 U1 Also known is a tool for multi-component injection molding of brush bodies, which is equipped with a reversing support, which can perform both a rotary and a lifting movement and demolded by the injection-molded body from the first mold cavity and by pivoting 180 ° in the second Mold cavity is inserted, whereupon this is then overmolded. Both this tool and turning tools are still relatively expensive in construction. In addition, it is disadvantageous in turning tools that the turning part has a comparatively large mass and thus a large moment of inertia, which causes increased wear in the drive.

The DE 44 17 986 A1 shows and describes a brush manufacturing machine for the production of plastic brush bodies, which consist of a plurality of successively molded components, wherein a plurality of mold cavities and a holding and transporting means are provided for transporting moldings from one mold cavity to another. The holding and transport means are spaced during the injection process from the respective injection area of the mold cavity and formed and arranged during or after a transfer process and after spraying the preform in a sprayed-ready during the first injection portion of the brush body.

task the present invention is to provide a tool for multi-component injection molding, which is simplified in terms of construction and its production cost Overall, significantly reduced.

This Task is a tool with the features of claim 1 solved.

By the transport through the crossbeams is for the injection mold itself a simple basic construction, as well as for one-component spraying used, can be used. The effort compared to turning tools for multi-component injection molding is considerably reduced.

Also the effort for the transport elements is compared to turning tools and too Tools with a reversing carrier lower. By the head-side holding the sprayed brush body body can existing Elements, namely anyway with the brush body head engaging punch can be used, which also simplifies the design contributes.

By the with the brush head molding area in same direction pointing first mold nests for the main body and the second form nests for the finished brush body, is sufficient for the transport of sprayed body from the first mold cavities to the second mold cavities a simple linear movement, which is mechanically easy to implement.

The alternately in the form of nests engaging crossbars allow for holding the brush body a very quick change, as both crossbeams simultaneously can be positioned in the opposite direction.

A embodiment provides that between the form plates, the crossbeams are arranged, wherein the outer contour of the one Crossbar is smaller than the clear inner cross section of the other Crossbeam.

By This construction results in a particularly stable and precise guidance of the Crossbeams.

advantageously, the crossbeams are laterally outside of the mold plates Longitudinal sliding guides stored, with the side supports Lifting drives for the lifting movement of the crossbeams are provided.

The Motion drives and guides for the Positioning movement of the cross members are thus outside the mold plates, so no changes must be made to the mold plates. Moreover, this is also a simple construction of the guides and the motion drives favored.

Conveniently, the longitudinal slide guides the crossbeams in the opening and closing direction of the mold arranged one above the other. The side next to the mold plates or next to the ejector-side mold plate only little space for the guides is claimed.

To another embodiment is provided that the Crossbars each within the outline of the mold plates Längsschiebeführungen have, with each of which lifting elements are connected to the each carry a cross-beam at their free ends.

Also this embodiment is simple in construction and allows a particularly space-saving design.

Conveniently, are in the crossbeams the Formnestabschnitte at least for brush head areas provided the ejector side mold plate, wherein in this ejector side Mold plate at the head of her Formnester receiving recesses are provided for receiving the crossbars and that the crossbars height adjustable and alternately at the different shape nesting areas of the Mold plates are positionable.

These Crossbeams with the head-side mold nest sections can ever varies according to the number and location of the mold cavity in size and to the respective Adapted requirements become.

To a small footprint and a design simplification also carries when in longitudinal sliding guides and / or the side supports and / or the lifting elements Hubantriebe are integrated.

To An embodiment of the invention are the first mold cavities and the second mold cavities in preferably aligned rows along one behind the other arranged.

To In another embodiment, the first mold cavities and the second Mold nests arranged in preferably parallel rows next to each other are.

Both embodiments is common that for the transport the main body from the first to the second mold cavities simple linear movements suffice. This is true even if the mold nest obliquely, however are arranged facing in the same direction.

The Alignment of the mold cavities with respect to the linear transport movement can depend, inter alia from the number of mold nests to be arranged side by side Formnestgruppe be provided.

additional Embodiments of the invention are listed in the further subclaims. below the invention with its essential details with reference to a embodiment closer by means of the drawings explained.

It shows something schematized:

1 a side view of a tool for multi-component injection molding with the injection mold open,

2 a plan view of an ejector-side mold plate with crossbeams for transporting the brush body,

3 a sectional view of the in 1 shown tool in one 1 appropriate position,

4 a view according to 3 , but here with closed injection mold,

5 a view 3 and 4 , here however with opened injection mold,

6 several molds arranged in a tool for multi-component injection molding,

7 a side view of a tool for multi-component injection molding with open mold with opposite 1 modified transport device and

8th a plan view of an ejector-side mold plate according to 7 with crossbeams for transporting the brush body.

An in 1 shown tool 1 is used for multi-component injection molding of plastic brush bodies 2 ( 5 ) for toothbrushes. These brush body consist in areas of several successively injected components. At first, it becomes a basic body 2a ( 1 . 3 to 6 ), which then in a second operation in certain areas to a finished brush body with a sheath 2 B is overmoulded.

This in 1 shown tool 1 has an injection mold 3 with an ejector side mold plate 4 and a nozzle-side mold plate 5 on.

As good with the ejector side mold plate 4 according to 2 recognizable, are two groups of mold cavities, namely first mold cavities 6a for spraying basic bodies 2a as well as second mold nests 6b for encapsulating the body and the Pre-filled syringes of the brush body 2 intended. Both the first and the second group of mold cavities consisting of several mold cavities arranged parallel next to one another. In the exemplary embodiment four mold cavities of a kind are arranged side by side, wherein the number also significantly larger, for example 16 Formnester can be next to each other.

It can also be clearly seen that the individual mold cavities of the first group are arranged in a longitudinal alignment with the individual mold cavities of the second group. Furthermore, it can be seen that they with their brush head areas 7 are arranged facing in the same direction.

Depending on the available space conditions, the mold cavities of the individual groups can also be arranged in a different position, for example transversely to the linear transport direction, in which the main body 2a from the first mold nesting group to the second one. In such an arrangement, the mold cavities are preferably arranged at right angles to the transverse members.

After spraying the main body 2a in the first form nests 6a These are in the second mold nest 6b transported.

Serve the crossbeams 13 and 14 , the side next to the ejector side mold plate 4 longitudinally displaceable on longitudinal sliding guides 11 and 12 are stored.

The crossbars 13 respectively. 14 are via lifting cylinders with the associated longitudinal sliding guides 11 respectively. 12 connected.

How good in 1 recognizable, are the crossbars 13 and 14 designed so that they can be moved past each other in opposite movements. Here is the clear inner cross section of the crossbeam 13 greater than the outer contour of the crossbeam 14 , As a result, the crossbeams can be moved in opposite directions practically opposite each other.

How good in 2 recognizable, have the crossbars 13 and 14 Cavity sections 18 for holding the brush head areas 7 on that together with those in the mold plate 4 located Formnestabschnitten 19a respectively. 19b the first mold nest 6a or the second mold nests 6b form.

For holding the crossbeams 13 and 14 are in the mold plate 4 preferably open-edged grooves 20 provided (cf. 3 to 6 ).

The recording grooves 20 are dimensioned so that the underside of the crossbeam 13 respectively. 14 arranged perforated pin retaining plates 21 Have space. At the punch pin retaining plates 21 are perforated pins 22 attached, which correspond in number and position to the later bristle field of the toothbrush. The hole pins 22 pass through guide holes 23 in the crossbeams 13 and 14 and protrude into the mold cavity area with the mold closed in the injection position (cf. 4 ).

The punch pin retaining plates 21 with the perforated pins 22 can be relative to the crossbars 13 and 14 moving from an injection and holding position ( 3 on the left side), where they protrude into the mold cavity, into an ejection position spaced apart from the crosspiece (US Pat. 3 right side), where they are from the sprayed-on brush body 2 are pulled out, are adjustable. The second form nests 6b assigned receiving groove 20 is for this extraction movement of Lochstifthalteplatten 21 with the perforated pins 22 formed correspondingly deeper.

Starting from the in 4 shown working position of the tool 1 with closed injection mold 3 , is the injection mold 3 opened, the ejector-side mold plate 4 from the nozzle-side, fixed mold plate 5 is moved away. In the injection process were simultaneously a number of basic bodies 2a and a series of servings 2 B to finished brush bodies 2 injected. In the 2 to 6 become the main body in the first mold cavities 6a left side and the finished brush body 2 , by wrapping 2 B from 2a in the second form nests 6b sprayed on the right side.

After opening the injection mold, the finished brush body 2 expelled, as in 5 is shown. These serve ejector pins 24 the on ejector plates 25 are attached. These are within a free space 28 between the mold plate 4 and a base plate 26 (see also 1 ) adjustable and with an ejector rod 27 connected.

After ejecting the finished brush body 2 , including the perforated pins 22 to be withdrawn become the crossbeams 13 and 14 over the lifting cylinders 17 from their recording recesses 20 lifted, so that in 3 position shown. In an opposite transport movement according to the arrows PF 1 and PF 2 move the crossbeams 13 and 14 along their longitudinal sliding guides 11 and 12 each in a change position, the cross-beam 14 empty at the receiving recess 20 the first mold nest 6a and the crossbeam 13 with basic bodies hanging from it 2a in the receiving recess 20 the second mold nest 6b to be brought.

During transport, the Grundkör per-moldings 2a at their head ends with the help of the piercing pins engaging there 22 kept safe. Then the mold is closed and it comes back to the initial situation, as in 4 after the subsequent injection process is shown.

For the transport movement of the crossbeams 13 and 14 along the longitudinal sliding guides 11 and 12 can preferably be provided pneumatic lifting actuators, which are optionally integrated in the guide rods of these longitudinal sliding guides. The crossbeams are laterally by lifting cylinder 17 supported. However, it could also be provided telescopic guides and separate Hubantriebe. As in 1 clearly recognizable, are the longitudinal sliding guides 11 and 12 on both sides of the mold plate 4 arranged one above the other to keep the lateral space requirement small.

The 3 to 6 make it easy to see that the partitions of the grooves 20 and the corresponding partitions on the cross members 13 and 14 are conically widening towards the free, open end. As a result, a self-centering when inserting the crossbeams 13 and 14 and achieved a precise fit in insertion position.

6 shows another tool 1 that mold by two mirror images arranged to a central plane of symmetry S injection molding 3 is formed. The nozzle-side, fixed mold plates 5 lie here directly at the plane of symmetry S together and close it, as in the tool according to 1 to 5 described, ejector-side mold plates 4 , Ejector plates 25 as well as base plates 26 outward. The advantage here is that you can accommodate a much larger number of mold cavities with the same circumferential cross section and that in this case despite this high number of mold cavities with respect to the injection molding machine same closing forces as in the forms according to 1 to 5 respectively. 7 and 8th suffice.

Except the in the embodiment construction shown there is also the possibility of one-sided on one Longitudinal slide bearing mounted Provide trusses. Furthermore could also a crossbeam on longitudinal sliding guides be guided the with the nozzle side Mold plate are connected.

The 7 and 8th show a tool 1 with one opposite 1 and 2 modified construction.

Midway between the mold plates 4 . 5 each is a longitudinal slide guide 29 . 29a arranged by two lifting elements 30 . 30a is longitudinally displaceable.

At the free ends of the lifting elements 30 is the crossbar 13 and on the lifting elements 30a the crossbeam 14 appropriate.

In the in 7 shown, extended position of the crossbars 13 . 14 These are in spaced-apart planes so that they can be moved past each other for the alternating movement. This allows the crossbeams 13 and 14 between the two form nest groups 6a . 6b be implemented alternately.

Characterized in that the guide and the associated lifting elements of the cross-beam 13 at the nozzle-side mold plate and the guide and associated lifting elements for the cross-beam 14 at the ejector side mold plate 4 can find the crossbeams 13 and 14 be easily moved past each other in a position change, with only a linear movement and a lifting movement are required here.

With the longitudinal sliding guides integrated inside the mold plates 29 . 29a can be very compact tools 1 realize. In addition, the design effort is again significantly reduced.

all these embodiments is common that each simple linear movements without turning movements for positioning the parts carrying the head-side mold cavity sections suffice.

1

Tool

2

brush body

2a

body

2 B

Envelope of the main body 2a

3

injection mold

4

Mold plate, the ejector

5

Mold plate, nozzle side

6a

first mold nest for 2a

6b

overmould second mold nest 2a

7

Brush head portion

11

Longitudinal sliding guide

12

Longitudinal sliding guide

13

crossbeam

14

crossbeam

17

lifting cylinder

18

Cavity section for brush head area

19a

Form nest section for mold nest 6a

19b

Molded section for mold nest 6b

20

recess for receiving the crossbars

21

Hole pin holding plate

22

Lochtstift

23

hole

24

ejector

25

ejector

26

baseplate

27

ejector

28

free space

29

Longitudinal sliding guide

29a

Longitudinal sliding guide

30

lifting

30a

lifting

Claims (17)

Tool ( 1 ) for multi-component injection molding of plastic brush bodies ( 2 ) for toothbrushes or the like, wherein the brush bodies ( 2 ) partially from several, successively injected components ( 2a . 2 B ) and wherein the injection mold ( 3 ) at least from an ejector side mold plate ( 4 ) and a nozzle-side, fixed mold plate ( 5 ), the first mold cavities ( 6a ) for spraying the basic body ( 2a ) as well as second mold nests ( 6b ) for injecting the main body ( 2a ) or for pre-spraying the brush body ( 2 ), wherein the basic body ( 2a ) from the first mold cavities ( 6a ) to the second form nests ( 6b ), characterized in that - the first and second mold cavities ( 6a . 6b ) with their brush head areas ( 7 ) are arranged pointing in the same direction, - in each case in the first and the second mold cavities ( 6a . 6b ) of the ejector side mold plate ( 4 ) Crossbeams ( 13 . 14 ) for holding the brush body ( 2 ) in the mold cavity section ( 18 ) for the brush head areas ( 7 ) are arranged, - in the mold plate ( 4 ) in the mold cavity section ( 18 ) the first ( 6a ) and second ( 6b ) Mold cavities each have at least one recess ( 20 ) for receiving the crossbars ( 13 . 14 ) are arranged and that - the crossbars ( 13 . 14 ) alternately, linearly between the two recesses ( 20 ) are movable back and forth. Tool according to claim 1, characterized in that between the mold plates ( 4 . 5 ) the crossbars ( 13 . 14 ) are arranged, wherein the outer contour of the cross-beam ( 14 ) is smaller than the clear inner cross-section of the cross-beam ( 13 ). Tool according to claim 1, characterized in that within the mold plates ( 4 . 5 ) Longitudinal sliding guides ( 29 . 29a ) for the lifting elements ( 30 . 30a ) are arranged, which at their free ends to the crossbeams ( 13 . 14 attack). Tool according to one of claims 1 to 3, characterized in that in the transverse members ( 13 . 14 ) Form nest sections ( 18 ) for the brush head areas of the ejector side mold plate ( 4 ) are provided and the crossbars ( 13 . 14 ) are height adjustable. Tool according to claim 1, 2 or 4, characterized in that the transverse members ( 13 . 14 ) laterally outside the mold plates ( 4 . 5 ) on longitudinal sliding guides ( 11 . 12 ) are mounted and lifting cylinder ( 17 ) the crossbars ( 13 . 14 ) laterally support and perform the lifting movement via a drive. Tool according to one of claims 1 to 5, characterized in that the lateral longitudinal sliding guides ( 11 . 12 ) for the crossbars ( 13 . 14 ) are arranged one above the other in the opening and closing direction of the mold. Tool according to one of claims 1 to 6, characterized in that in the longitudinal sliding guides ( 11 . 12 . 29 . 29a ) and / or the lifting cylinders ( 17 ) Hub drives are integrated. Tool according to one of claims 1 to 7, characterized in that in the ejector side mold plate ( 4 ) recesses ( 20 ) for receiving the crossbars ( 13 . 14 ) as a continuous, open-border grooves ( 20 ) are formed. Tool according to one of claims 1 to 8, characterized in that the partitions of the receiving recesses ( 20 ) for receiving the crossbars ( 13 . 14 ) and the partitions of the crossbars ( 13 . 14 ) are conically formed in the transverse to the longitudinal extension of the mold cavity extending separation region. Tool according to one of claims 1 to 9, characterized in that below the crossbars ( 13 . 14 ) Punch holder plates ( 21 ) with piercing perforated pins ( 22 ) are arranged. Tool according to one of claims 1 to 10, characterized in that on the mold cavities ( 6a . 6b ) facing away from the ejector side mold plate ( 4 ), between a base plate ( 26 ) and the mold plate ( 4 ), Ejector plates ( 25 ) are arranged, on which the ejector pins ( 24 ) are mounted. Tool according to one of claims 1 to 11, characterized in that in the tool ( 1 ) one or two central, nozzle-side mold plates ( 5 ) and on both sides adjoining, Auswerferseitige mold plates ( 4 ) are arranged. Tool according to one of claims 1 to 12, characterized in that the first mold cavity ( 6a ) and the second mold nests ( 6b ) in preferably aligned rows along one behind the other are arranged. Tool according to claim 13, characterized in that for the basic body ( 2a ) and for the finished brush body ( 2 ) parallel rows of juxtaposed mold cavities ( 6a . 6b ) are provided, preferably four to sixteen mold cavities. Tool according to one of claims 1 to 12, characterized in that the first mold cavity ( 6a ) and the second mold nests ( 6b ) are arranged side by side in preferably parallel rows. Tool according to claim 3, characterized in that the longitudinal sliding guides ( 29 . 29a ) are arranged approximately centrally and longitudinally within the mold plates. Tool according to one of claims 1 to 16, characterized in that the longitudinal sliding guides ( 29 . 29a ) and the respective transverse members ( 13 . 14 ) each have two parallel and preferably spaced-apart lifting elements ( 30 . 30a ) are interconnected.