CA2024150A1

CA2024150A1 - Die-cast machine

Info

Publication number: CA2024150A1
Application number: CA002024150A
Authority: CA
Inventors: Walter Dobler
Original assignee: Walter Dobler; Systec Rationalisierungstechnik Knauer Gmbh & Co. Kg; Systec Engineering Knauer Gmbh And Co. Kg
Current assignee: Systec Engineering Knauer GmbH and Co KG
Priority date: 1989-08-30
Filing date: 1990-08-28
Publication date: 1991-03-01
Also published as: ATE101819T1; EP0415153A2; ES2051422T3; DE3928680A1; EP0415153B1; DE59004667D1; DK0415153T3; EP0499676A1; EP0415153A3; JPH0390326A; JPH0749210B2

Abstract

ABSTRACT OF THE DISCLOSURE

In the insertion and removal system for a die-cast machine which has mould sections that can move relative to each other, at least one separate insertion element and at least one separate removal element are moved by means of a direct drive coupling to the moving parts of the mould during the opening movement of the parts of the mould between an insertion point and a removal point and one or the other of the mould parts by which means the intervening time between two processing steps of the die-cast machine are considerably reduced, which are determined by the insertion and removal of workpieces. Because of the special configuration and relationship of the elements and their driving elements, it is possible to bring about a considerable enhancement of operating safety of this apparatus.

Description

~2~

The present invention relates to an insertion and removal system for a die-cast machine with machine parts that can move relative to each other and with an insertion or removal element that can be moved into the space between the machine parts that have been moved apart, this element being driven by a moveable section of the mould.

An apparatus of the type described heretofore in which when the male die and a female die of a die-cast machine are moved apart, a removal element, driven by the mould parts that are moved, can be inserted between the two sections of the mould in order to remove a workpiece and then on the subsequent return movement of the mould sections into their closed position, can be moved back, outwards, with the workpiece, is already known. Such an element with a double head is also known; with this an intermediate product can be installed in one part of the opened mould and a finished workpiece can be removed from the other portion of the plastic mould or vice versa. However, such a double-headed element calls for a complex structure, complicated control, and a longer period during which the plastic mould is open, since the two functions of the double head can only ba carried out with additional driving means, and the tools have to move along different working paths. However, the shortest possible opening times of the die mould are required in order to achieve the maximum utilization of a die-casting machine.

It is an object of the present invention to provide an apparatus of the type described wherein it is possible to bring about a further reduction of the insertion and removal steps that interrupt production, and which is so configured as to ensure reliable operation even at relatively high operating speeds.

According to the present invention there is provided an insertion and removal apparatus for a die-cast machine, comprising mould parts that can be moved relative to each other and an insertion or removal element that can be moved into the space between the parts of the mould that have been moved apart, this being driven by a moveable part of the mould, wherein an insertion element and a removal element are provided as separate parts that can be moved simultaneously by the parts of the mould into and out of the space between the parts of the mould.

Because of the adjustment both of a separate insertion element and also of a separate removal element that takes place simultaneously with the movement of the machine parts, the time re~uired for relative adjustment of the mould parts is used in optimal fashion and without any prolongation for the insertion process and for the removal process, which is only possible when using known elements when only one of the two processes, which is to say only an insertion or only a removal, is to be completed. During the time in which the die-cast machine is in productive use, the insertion element can be loaded with a pre-product and the removal element can be freed of a workpiece that has been removed. The whole of the die-casting time can be used for these processes, which facilitates precise positioning of a pre-product in an insertion element and the proper blow-out or drop-out of a finished product from the removal element.

The reliable method of operation of the apparatus configured according to the present invention can be improved even more by the preferred features of the invention. Thus, at least one part of the motion of the insertion element and/or the removal element can be brought about (forced) by control curves (radial cams) that are formed rigidly on those parts of the mould that can be moved relative to each other, against which adjusters of the elements or element carriers are held under tension. Positioning inaccuracies caused by free play can be greatly reduced by means of such fixed radial cams, which is particularly important in the case of insertion elements used to install cores, inserts, or housing parts into a die~cast mould. If the elements are to follow complicated movement paths, the insertion and/or the removal element can be arranged on separate element carriers that are supported on one of the parts of the mould in such a way as to be moveable. In this case, too, additional drive elements can be provided that are not driven directly by the parts of the mould, but rather are only controlled by them, for example, a piston-cylinder arrangement that is used to rotate the insertion element.

The apparatus according to the present invention is particularly suitable for plastic die-casting machines, in which a printed casing foil section has to be installed in a part of the mould by means of at least one insertion element that is preferably in the form of a suction die (male suction die), whereas a removal element, of which there is at least one, and which is preferably formed as a suction retaining arm picks up a finished die-cast part to which the printed casing foil section has been applied simultaneously from the other part of the mould. In this way, it is possible to dispense with subsequent printing of the plastic cups.
Because of its appropriate configuration, the insertion element permits precise positioning of the casing foil section. A combination of the insertion and/or removal elements with a control and monitoring system for the die-cast machine makes it possible to establish whether or not pre-products, such as the casing foil section referred to above, have been picked up by the insertion element and whether or not the removal element has actually picked up a finished workpiece; this can be done by means of sensors arranged on the elements. It is, of course, understood that the apparatus configured according to the present invention can also be used with only one of the two elements, in which case the other element can be dispensed with for a production process.

2. ~` 2, ~

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings in which:-Figure 1 is a diagrammatic side view of the machine parts ofa first embodiment of a plastic die-cast machine;

Figure 2 is a diagrammatic plan view of a die-cast machine used for plastic which incorporates the die-cast tools with the insertion and removal elements, with the tool being open;

Figure 3 is a view from below of the die-cast tool shown from above in figure 2 in which the die-cast mould is open;

Figure 4 is a diagrammatic plan view corresponding to figure 2 of a die-cast tool of a second embodiment of a plastic die-cast machine with the tool open and the insertion and removal elements installed;

Figure 5 is a cross section through the open die-cast mould on the line V-V in figure 4;

Figures 6a to 6c show partial views of the removal element in three different ànd sequential operating positions of this element.

Figures 1 to 3 show two machine parts 11 and 12 of a die-cast machine used for plastic, these parts being moveable relative to each other. Each tool part is provided with at least one-half of a mould that works in conjunction with the second half of a mould on the other tool part. Thus, the machine or tool part 11 incorporates a male die 13 that works in conjunction with a female die 14 and a mould base 15 and these are both arranged on the machine part 12. The male die 13 and the female die 14 together with the mould base 15 form a die-cast mould for the production of plastic cups. Figure 2 ~

1 also shows a second similar female die 14' with the mould base 15' on the machine part 12.

The insertion and removal apparatus for a die-cast machine has a separate insertion element in the form of a suction die 16 and a separate removal element in the form of a suction retaining arm 17 for each die-cast mould, and these are shown in figures 2 and 3. The suction die 16 is used to insert a printed casing foil section 18 in the female mould 14 and is so supported on a machine part 12 so as to be rotatable on a shaft 19 and in figure 3 on a swinging arm 20 that is only indicated by means of an axis line. The rotating motion of the swinging arm 20 through an angle of 180D is effected by a slide 21 that is also mounted on the machine part 12, this being done in a manner not shown herein; a roller 22 of this slide 21 lies against the control curve 23 that is formed on a cam plate that is fixed rigidly to the adjustable machine part 11. A serrated bar 25 is formed on the slide 21 and this engages with a pinion 26 that is secured to the shaft 19, the tilting motion being imparted to the arm 20 by means of this.

The suction die 16 is supported on the swinging arm 20 so as to be able to rotate about a shaft 27 to which a notched-belt pulley 28 is secured. This notched-belt pulley i5 connected through a notched belt 20 to a notched-belt pulley 30 that is freely rotatable on the shaft 19. The notched-belt pulley 30 is coupled to the piston rod 31 of an adjusting cylinder 22 with the help of which an additional turning motion through 90 can be imparted to the suction die 16. Figure 3 shows the suction die 16 in different tilt positions, and this is moved through the tilting movement of the swinging arm 20 between the female die 14 and a loading point 33 where a pre-printed foil strip 34 is introduced, and from which the casing foil section 18 is separated in a manner not shown herein.

Figure 2 shows the arrangement of the removal element that is configured as a suction retaining arm 17. The suction retaining arm 17 is secured so as to be able to rotate about a shaft 44 and is secured to a swinging arm 35 that is also indicated only by an axis line. It is of an angular shape and serves to pick up a plastic cup 40 that has already been sprayed and is standing on the male die 13. Figure 2 shows the suction retaining arm 17 in different pivoted positions.
The swinging arm 35 can be pivoted through an angle of 90.
To this end, a pinion 36 is secured to the pivoting axis 44 and this engages into a serrated bar 37 that is formed in a manner not shown herein on a slide 38 that can move longitudinally on the machine part 11. A roller 39 of the slide 38 is held in contact with the radial cam 41 that is formed on a cam plate 42 that is rigidly connected to the machine part 12.

During the movement of the two machine parts 11 and 12, the two swinging arms 20 and 35 are rotated about their axes of rotation 19 and 44 by the cam controlled slides 21 and 38.
In the embodiment shown, both slides 21 and 38 are parts of a compressed-air cylinder and are under pressure that holds the rollers 22 and 39 of the slides 21 and 38 in constant contact with the cam plate 23 or 41. As the mould opens into the completely open position shown in figures 2 and 3, the suction die 16 together with a casing foil section that is picked up at the loading point 33 is moved inwards into the female die 14. There, the casing foil section 18 is released from the suction die 16 and held in the female die 14 by means of a suction system (not shown herein) of the machine part 12 that acts in the gap 43 (figure 1) between the female die 14 and the base of the mould 15. At the same time, the suction retaining arm 17 is moved with the swing arm 35 inwards to the male die 13 where it picks up the die-cast plastic cup 40 that is still standing on the male die 13.
During the closing movement of the mould, during which the two machine parts 11 and 12 are moved towards each other, the 2~2L~.L ~

suction die 16 and the suction retaining arm 17 are pivoted back outwards, when the suction retaining arm 17 brings the plastic cup 40 into an outer ejection position.

Both the suction die 16 and the suction retaining arm 17 can be fitted with sensors, in a manner not shown herein, that are part of a control and monitoring system of the plastic die-cast machine; these sensors determine whether or not the two elements contain workpieces as they should or not.

It is understood that the pivoting range of the swing arms 20 and 35 and also the angle of rotation of the suction die can be adjusted to other suitable values.

Figures 4 to 6 show the machine parts 11' and 12' of a plastic die-cast machine which can be adjusted relative to each other; in this machine, the insertion element and the removal element are configured other than is shown in the embodiment shown in figures 1 to 3. In these drawings, comparable parts of the apparatus bear the same reference numbers as in figures 1 to 3 r supplemented in each case by an apostrophe. Here, too, the male die 13' and a female die 14' together with the mould base 15' form a die-cast mould for the production of conical plastic cups. Figure 5 also shows a second similar female die 14' on the machine part 12'.

The insertion element 16' is in the form of a plate that can rotate about a shaft 45, on which there is a suction retaining bar 46 for each female die 14'. The rotary movement of the plate 16' of the insertion element is effected by means of a control curve that is connected rigidly with one of the machine parts; this is not shown in the drawing. Figure 4 only indicates one control curve 41' for the removal element that is configured as a suction retaining arm 17'. The insertion element 16' and the removal element 17' are shown in figure 4 in their innermost end position by way of dashed lines. Their outermost end position i5 shown with a dashed-dotted line and their pivoting range is indicated by means of an arc and a double-headed arrow 47.

The insertion and removal system is associated with a charging system 48 for the suction retaining bars 46. The charging system 48 incorporates a~gripper for each suction retaining bar 46 and this incorporates two gripper arms 49.1 and 49.2 that can pivot about a common axis. The unattached ends 49.3 of the pivoting gripper arms are configured as suction retaining points for the printed casing hull sections 18' that are to be applied, that are first held against the `
suction retaining bar with a central pressure bar 49.4 of the gripper 49 before they are wrapped around the conical suction retaining bar 46 by means of the individual gripper arms 49.1 and 49.2 that are moved individually by means of the pneumatic piston-cylinder units 50.1 and 50.2. The gripper construction that is used permits extremely precise positioning of the printed hull casing section 18' that is positioned with corresponding accuracy in the conical opening 51 of the female die 14'.

The removal element in the form of a suction retaining arm 17' that is supported so as to be able to rotate about an axis of rotation 52 that is shown in figure 4 and whose rotating movement is achieved by means of the control profile 41' produces a rotation of the cup about 90 in a plans that is perpendicular to the plane of rotation when a finished die-cast cup with its applied casing foil section is removed.
To this end, as is shown in figure 6, the suction holder 53 that grasps the plastic cup 40' at its base portion is arranged at the end of a swinging arm 54 that is supported at its other end so as to be able to pivot about an axis 55 in the suction retaining arm 17'. The swinging arm 54 is fitted with a coaxial toothed ring 56 that engages in a serrated bar 57 that can be moved relative to the suction retaining arm 17'. The serrated bar 57 is coupled mechanically with the ~2~

pivoting mechanism for the suction retaining arm 17' (not shown herein) such that its relative movement vis a vis the suction retaining arm 17' takes place as a function of its pivoted position such that in the inner pivoted position of the suction retaining arm 17' that is shown in figure 6a, the swinging arm 54 is oriented in the direction of the suction retaining arm 17' and in the outer end position that is shown in figure 6b, it assumes a position that is perpendicular to the suction retaining arm 17'. In this position, the partial vacuum at the suction holder 53 is switched off and the swinging arm S4 is withdrawn by the return movement of the serrated bar 57 in the direction indicated by the arrow 58 into the position that is shown in figure 6c. This means that the plastic cup 40' can drop into a stacking chute in the direction indicated by the arrow 59 in such a position that it is ready for stacking.

In the embodiments of the insertion element and the removal element shown in figures 4 to 6 the insertion element and the removal element can also be fitted, in a manner not shown herein, with sen~ors that are part of a control and monitoring system for the plastic die-cast machine, with the help of which it can be determined whether or not the two elements contain workpieces as they should or not.

Claims

1. An insertion and removal apparatus for a die-cast machine, comprising mould parts that can be moved relative to each other and an insertion or removal element that can be moved into the space between the parts of the mould that have been moved apart, this being driven by a moveable part of the mould, wherein an insertion element and a removal element are provided as separate parts that can be moved simultaneously by the parts of the mould into and out of the space between the parts of the mould.

2. An apparatus as claimed in claim 1, wherein at least one portion of the movement of the insertion element and/or of the removal element is brought about by the control curve that is formed on the parts of the mould that can be moved relative to each other, against which adjusters of the elements or of element carriers are held under tension.

3. An apparatus as claimed in claim 1, wherein an additional pivoting movement of the insertion and/or removal element is brought about by means of a serrated bar that is formed on one part of the mould ) or on an element carrier.

4. An apparatus as claimed in any one of claims 1 to 3, wherein a slide supported on one of the parts of the mould is provided as an element carrier for the insertion and/or removal element.

5. An apparatus as claimed in any one of claims 1 to 3, wherein a piston-cylinder unit is mounted on one of the relatively moveable parts of the mould or on an element carrier as an additional drive element for rotating the insertion element.

6. An apparatus as claimed in any one of claims 1 to 3, wherein the insertion element comprises a suction die for a printed casing foil section, and the removal element comprises a suction retaining arm for a die-cast part, each of these being arranged on a swinging arm.

7. An apparatus as claimed in any one of claims 1 to 3, wherein the insertion element comprises a suction retaining bar for a printed casing foil section and the apparatus is associated with a loading system for the suction retaining bar that incorporates a gripper for the casing foil section with pivoting gripper arms to apply the casing foil section against the suction retaining bar.

8. An apparatus as claimed in claim 1, wherein a suction holder for a workpiece is arranged on the removal element at the end of a swinging arm, which in order to achieve a change in the position of the workpiece that has been picked up relative to the removal element can be pivoted through at least 90° in the removal element.

9. An apparatus as claimed in claim 8, wherein the swinging arm is connected to a coaxial toothed ring that engages in a toothed rod that can move relative to the removal element.

10. An apparatus as claimed in any one of the claims 1 to 3, wherein the sensors of a control and monitoring system that is used to determine the filled status of the elements are arranged in the insertion and/or removal elements.