JPS63139502A - Molding station - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION ON THE STARROOL The invention provides a sole for the shoe shaft with a sole of the elastomeric family and an intermediate sole of a layer of a mixture of isocyanates and polyols completely reactive with polyurethane. A molding station for integral molding, in particular for circular table devices, in which the intermediate sole and the sole are bonded to each other by chemical bonds between the isocyanate and the substance added to the reactive end groups of the elastomer. and the molding station has a height-adjustable beam with a pivotably mounted mold part holder;
the mold part holder has at least one heatable mold part for forming the sole, and below the height-adjustable beam a second height with a heatable plate; An adjustable beam is arranged, the plate cooperating with a heatable mold part of the pivotable mold part holder to form the sole, the pivotable mold part holder forming the intermediate sole. It is of the type that cooperates with a lateral mold part and a shoe shaft placed over the shoe shell for forming the shoe.

PRIOR ART Shoes with an intermediate sole made of polyurethane and a sole also made of polyurethane are known (West German Patent No. 22).
41493 specification).

To produce such shoes, a circular table apparatus with several molding stations with molds is generally used (Brochure of Kretzner Feromatik Desma, Injection Tie-Left Shoe Molding Machine DESMA No. 521
Pages 526 to 526).

The round table device has two mixing devices for mixing isocyanate and polyol into a mixture that is completely reactive with polyurethane, and depending on the mixing ratio and additives, the mixture is mixed into abrasion-resistant soles or abrasion-resistant soles. Fully responsive with elastic midsole.

The circular table is rotated in steps to form the sole and midsole. In this case, the forming station is engaged with both mixing devices one after the other.

Both mixing devices are arranged radially movably around and towards the circular table. The molding station has two side mold parts defining one notch and two injection channels in the closed position.

A shoe last swivel body having a last for receiving a shoe shaft and an opposing punch is arranged above the side mold part in a height-adjustable manner.

A bottom punch is arranged under the side mold part so that its height can be adjusted. To form the sole, the sole punch, the side mold parts (in the closed position) and the opposing punch define a cavity into which a mixture is provided which is completely reactive to the sole.

To form the midsole, a sole punch with the sole and the lateral mold parts (in the closed position) and the sole covered with the shoe shaft define a cavity into which the midsole is formed. A completely reacted mixture is obtained, and the intermediate sole is completely bonded to the sole and shoe shaft during the course of the reaction.

According to section 6(2) of the West German Patent Act, a molding station for a circular table for molding soles with an elastomeric sole and a polyurethane midsole is known (P Al 682.3). ).

To mold soles of the elastomeric family, the elastomers are plasticized, as is known, in injection molding machines that process thermoplastic materials instead of in mixing equipment that mixes completely reactive mixtures into soles of the polyurethane family. A plasticizing and injection unit is used, in which the elastomer is then injected into the cavity for the sole. Because of the high pressures that occur during the injection of plasticized elastomers, the known molding station according to Section 3(2) of the Patent Act has a height-adjustable beam with a pivotably mounted mold part holder. A heatable mold part with a cavity corresponding to the sole of the shoe and additionally provided with cooling channels is arranged on the side surface of the mold part holder parallel to the pivot axis.

A second height-adjustable beam is arranged below this beam, which beam has a heatable plate on the side facing the pivotable mold part holder, which plate has a heatable plate. cooperates with the heatable mold part of the mold part holder to produce the mold part holder.

A further beam with a recess is arranged immovably above the beam with the pivotable mold part holder. A heatable mold part enters this notch together with the elastomeric sole located in the cavity, two lateral mold parts located above the notch, a heatable mold part and a polyurethane mold part placed over the last. work together to form a made midsole.

Mixtures for soles and midsoles that are fully reactive with polyurethane include primarily polyols, isocyanates, chain extenders, and catalysts, and these mixtures contain the desired materials for soles or midsoles. Depending on the properties (that is, the sole should preferably be wear-resistant and the midsole should be elastic and have a porous structure), suitable additives are used.

A chemical reaction begins already when the ingredients are mixed. The mixture completely reacts with the sole or midsole in the mold. Upon complete reaction of the mixture for the midsole, the midsole is simultaneously formed and the connection with the shaft and sole is achieved.

The elastomeric sole and the polyurethane midsole are bonded to each other in the area of their interface by chemical bonds between the isocyanate and the reactive end groups of the substances added to the elastomer.

A mixture that completely reacts with polyurethane is a mixture mainly composed of ether or ester polyolene, and this mixture contains 60 to 100% by weight of isocyanate, 0.1 to 10% by weight of catalyst, and the balance based on 100% by weight. It also contains chain extenders and other conventional additives.

The catalyst used is in particular the catalyst DABCO-8B, which is available on the market under the tradename Aerozorodacts.

The elastomer from which the sole is made may be mixed with the following compounds or chemicals, such as acrylonitrile rubber, styrene-butadiene rubber, natural rubber, chloroprene rubber, in a proportion of 0 to 20 phr based on the amount of bim.

Shoe soles can generally be made from all known rubbers, for example when the following substances are incorporated in amounts of 0 to 20 phr (based on the rubber used): Phenol-formaldehyde resins, for example: Vulka
dur A (Bayer AG), Coretack
(BASF) Methylolated phenol-formaldehyde resins, e.g.: SP 1045 (Krahn) Korever (BASF) Resorcin, e.g.
rasil (Degussa) Amino alcohols, such as: 6-amino-zolopanol Primary or secondary amines, such as: Stearylamine Holivinyl alcohol, e.g. Eva: Mowiwol (Hoechst) vs H72 (A
IRPRODUCTS)VSH73(AIRPROD
UCTS) polyols with high hydroxyl group content, for example: Formrez (Witco) acrylate rubber (ACM), for example; Hydrin
(Polysar) Herclor (Hercu
les ) or a combination of the above-mentioned materials The formation of soles made of elastomers is carried out as follows. That is, the elastomer is plasticized at normal processing temperatures and injected into appropriate cavities in an injection molding machine at correspondingly high pressures as in conventional technology.

Control of the temperature of the elastomer is performed as follows. That is, the temperature of the injected sole is cooled to just below the additive temperature of the polyurethane of the midsole to be formed, and then a mixture completely reactive with the polyurethane is brought into contact with the molded sole, in this case The reactive end groups of the isocyanate react in the polyurethane boundary layer which completely reacts the elastomer.

In practice, when controlling the temperature of the elastomer, a temperature increase or decrease of 100 C causes a shortening or lengthening of the vulcanization time, ie the time for the questomer to fully react, by 50%.

The cooling rate of the elastomer grave sole to the temperature at which the mixture completely reacts with the polyurethane cleft midsole is supplied to the cavity for the midsole is determined primarily by the mold part placed in the pivotable mold part holder. defined by its high heat capacity.

As a result of this cooling rate, the time for forming and cooling the sole is significantly longer than the time required to form the midsole.

A special problem also arises with arrows.

That is, cooling the sole from the relatively high temperature at which the plasticized elastomer is injected to the temperature for forming the midsole changes the dimensions of the sole to an extent that is no longer acceptable. That is, in general it is impossible to ignore this shrinkage in all elastomers, and therefore the mold part with the cavity that serves to mold the sole made of elastomer cooled with a mold part, the sole for the side molding. It is not possible to co-operate with the last part and the shoe shaft placed over the last for the production of the midsole.

SUMMARY OF THE INVENTION It is an object of the invention to improve a molding station of the type mentioned at the outset and to provide a molding station which takes into account the aforementioned shrinkage in elastomer soles.

In order to achieve this object, the invention provides a configuration in which the pivotably mounted mold part holder is provided with a shoe support on a side parallel to the second height-adjustable beam. a mold part with a cavity for the sole and cooperating with the heatable plate, and a side mold part with a cavity on the other side for receiving the already molded sole; and a mold part cooperating with the shoe shaft placed over the last, on a beam with a pivotably supported mold part holder;
A height-adjustable last receiver with a last swivel is arranged, the last swivel having a last for a shoe shaft;
and a vacuum-loadable punch for taking off the molded sole and transferring it after cooling into the cavity for the molded sole.

Effects of the Invention With this construction, the still hot elastomer sole is received by the opposite punch of the sole receiver, which can be subjected to a vacuum or negative pressure, and after cooling it is cooled slowly with only a slight shrinkage. For this purpose, it is passed into a cavity in a mold part which cooperates with the lateral mold parts and the shoe shaft, which is placed over the last, in order to form the polyurethane midsole.

The dimensions of the cavity for molding the elastomer sole are such that, after cooling in the opposed punch, the sole has the predetermined dimensions in the finished shoe, i.e. the side mold parts and the shoe overlaid on the last. The cavity of the mold part cooperating with the shaft is likewise configured to have the dimensions of the sole after cooling, ie in the final state.

According to an embodiment of the invention, a mold part with a cavity can be applied with a vacuum for receiving the sole, the mold part having a hole opening into the cavity.

Example The invention will now be described in detail with reference to the drawings.

FIG. 1 schematically shows a circular table arrangement in plan view. On the circular table 1 of this circular table arrangement, fourteen forming stations 2 are arranged, indicated by squares, which at the same time also indicate the positions occupied by the forming stations during a stepped rotation of the circular chidel. In the illustrated embodiment, each molding station returns to its original position after 15 steps of the circular table. These positions are designated 2o1-214.

Arranged around the circular table is a plasticizing and injection unit 3 for the elastomer, which plasticizing and injection unit 3 is moved after each working step by a radial movement towards the circular table (see double arrow). Position 2o each time
1 is brought into engagement with forming station 2. As soon as the plasticizing and injection unit 3 engages the molding station, the elastomer is injected into the molding cavity for the sole.

Furthermore, a mixing device 4 for mixing the polyurethane-reactive mixture is also arranged radially movably towards the circular table. After each working cycle this mixing device 4 likewise moves to the corresponding working position 203.
can be engaged with the working station which has reached this point, whereby the intermediate sole is formed. The unit 3 and the mixing device 4 depending on the reaction time or vulcanization time of the materials used.
can also be exchanged with each other.

2 to 6 show embodiments of the molding station according to the invention in side views in different working positions, ie in the direction of the plasticizing and injection unit 3 or the mixing device 4.

FIG. 2 shows the molding station 2 and the mold parts for molding the sole and the midsole in the closed position.

The forming station has four molds, only two of which are visible in the drawing.

Together with a fixed beam 6 and a beam 8 with a cutout 7, the guide forms a fixed guide frame for a height-adjustable beam 9, which is connected to a pin 10. It has a mold part holder 11 which is rotatably supported around the mold part holder 11.

A second height-adjustable beam 12 is arranged below the height-adjustable beam 9 .

This height-adjustable beam 12 has a mold-holding cylinder 13 on the side facing the beam 6 and a heatable plate 14 on the side facing the beam 9.

Two running cylinders 15 are fixed to the beam 6, the piston rods 16 of both running cylinders being connected to the height-adjustable beam 12.

In the position shown in FIG.
It has a mold part 17 with a mold part 17 having the dimensions of the sole to be molded. The mold part 17 is arranged in a heating block 19 which is itself connected via a heat-insulating plate 20 to a pivotably mounted mold part holder 11 .

The mold part holder 11 has, on a second side opposite to the beam 12 and parallel to it, a cooling plate 21 through which a cooling medium flows. A mold part 22 is arranged on the cooling plate 21 .

This mold part 22, which is cooled by a cooling plate 21, has a cavity 23 corresponding to the dimensions of the sole of a shoe.

Inside the beam 8 and above its recess γ two mold parts 24,25 for side shaping are arranged, both mold parts delimiting a recess in its closed position, which recess A shoe shaft 27 placed over a last 26 and a mold part 22 with a formed sole (not shown) together form a cavity for molding the midsole.

When injecting soles made of elastomer, high injection pressures occur, similar to those in injection molding machines processing thermoplastic materials. It is necessary to provide

As can be seen from FIG. 2, during the injection of the plasticized elastomer into the cavity 18 bounded by the heatable plate 14 and the mold part 1γ in the closed position, the reaction force is formed by the beams 6 and 8. The mold part holder 11, which can be pivoted, is supported in the edge region of the recess T in the beam 8.

The height-adjustable beam 9 is entrained via a rond (not shown) when the beam travels, so that in the position of the travel cylinder shown in FIG. 6, the beam occupies the position shown.

The forming station is placed on a beam 8 with a cutout 7;
It has a height-adjustable last receiver 29, known per se, with a last swivel 31 which can be pivoted about a pin 30.

The shoe last rotating body 31 includes a shoe last 26 and an end plate 33'.
A punch 32 provided for this purpose is fixed.

The plate 33 has passages 34 opening on its surface, to which a vacuum or negative pressure can be applied via a vacuum device (not shown).

In FIG. 2 the position of the beam of forming station 2 at position 201 is shown.

In this position, the plasticizing and injection unit 3 is moved radially towards the molding station. Cavity 18
The plasticized elastomer is injected into the cavity.

The cavity 18 has a molding station from position 201 to position 2°21203 + 204 +...12oa l 20 according to the appropriate number of steps for making the circular table.
9.2. . It remains closed until it reaches position 211 again.

In the vertical position 211 obtained again, the traveling cylinder 15 is
Both height-adjustable beams 9, 12 are loaded so that they occupy the position shown in FIG.

In this position of both beams, the pivotably supported mold part holder 11 is swiveled through 180°, so that the cooled mold part 22 is located opposite the heated plate 14 and the still hot elastomer The mold part 17 with the split sole occupies the position of the mold part 21 shown in FIG.

The height-adjustable last receptacle shown in FIG. 2 is moved from the next shoe to its upper handle position, while at the same time both mold parts are moved to their maximum open position. . The last swivel is swiveled through 180 DEG so that the end plate 33 of the punch 32 is directed toward the elastomer sole.

As shown in FIG. 4, the height-adjustable last receptacle is moved into its lower end position, at the same time the running cylinder 15 moves the movable beam 12 and the spring 36 moves the upper beam 9. This movement continues until the sole is contacted by the plate 33.

The passages 34 of the plate 33 are then loaded with a vacuum or negative pressure, so that the sole is taken up by the plate 33.

As shown in FIG. 3, the slidable beam 9 with the swivelably supported mold part holder 11 is moved into the lower position shown in FIG. A pivot range for pivoting the pivotable mold part holder is opened.

In this position of the slidable beam 9, the pivotable mold part holder is swiveled through 180 DEG, so that the cavity of the mold part 22 is again oriented towards the sole.

The slidable beam 9 with the pivotable mold part holder is then moved into the upper position shown in FIG. 6, in which the cavity of the mold part 22 is further directed towards the plate 33.

The height-adjustable last receiver is moved towards the mold part 22 until the cooled elastomeric sole contacts the cavity 23 in the meantime.

The channels 34 of the plate 33 are then subjected to pressure, so that the cavity 23 receives the sole of the shoe. The mold part 22 may have a hole 35 opening into a cavity, so that the cooled sole is taken over by the vacuum load. After ejecting the sole into the cavity 23, the height-adjustable last receiver is moved to the upper position shown in FIG. In this position the last swivel is pivoted by 180° so that the last with the shoe shaft placed over it is directed towards the sole.

The side mold parts are brought into a closed position and the slidable beam with the pivotable top part holder is moved towards the side bottom mold parts until contact is made.

At the same time, the height-adjustable last receiver is moved towards the lateral mold part in the closed position, and this movement causes the sealing seat of the shoe shaft, which is placed over the last, to be positioned in the lateral mold part. It continues until

Through injection holes (not shown) confined by the side mold parts in the closed position, the polyurethane-reactive mixture is injected into the shoe shaft and shoe over the side mold parts and last. brought into a cavity confined by the bottom.

The shoe with the finished sole is then demolded and a new shoe shaft is placed over the last.

As can be seen from the foregoing, in the stationary operation of the circular table device, the sole and the midsole are simultaneously injected, and at the same time the finished shoe is injected at a take-off station (not shown) in the area between positions 204 or 214. The shoe shaft of this shoe is integrally molded with a sole comprising an elastomer sole and a polyurethane midsole.

Therefore, by the inventive configuration of the forming station,
Furthermore, a circular table device with short step times is obtained.

It is also within the scope of the invention to use the molding stations individually, which is particularly advantageous in non-volume production and in experimental production. For this purpose, the mixing device for mixing the completely reactive mixture for the polyurethane and the plasticizing and injection unit for the elastomer must be arranged, for example, one above the other or diametrically opposite each other.

As already mentioned, the injection of the plasticized elastomer into the cavity for the sole shoe takes place at position 2.1 of one of the molding stations 2, which molding station then slides onto the slideable beam. Move from position 201 to position 211 without changing the position. Standing 20,
to position 203, the movement of the slidable beam and the slidable sole receiver and the pivoting of the pivotable mold part holder and the shoe last swivel as described above with respect to FIGS. A movement is carried out, after which the closed cavity of the intermediate sump is fed with a mixture which completely reacts with the polyurethane. This applies to all molding stations 2.

The same holds true for round table arrangements with multiple or fewer molding stations and round table positions.

The particularly significant advantages of the device according to the invention include the following. Thus, according to the invention, different mold parts are used for completely vulcanizing the injected elastomer sole and for cooling the fully vulcanized sole,
As a result, the time for complete vulcanization and the time for cooling can be determined independently of each other.

Yet another big advantage is: Thus, according to the invention, the total time required for complete vulcanization and the time for cooling the sole for subsequent processing is reduced by first heating the sole for complete vulcanization and then cooling the sole for subsequent processing. This is significantly shorter than when using a cooled mold section to cool the mold.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the circular table device, Fig. 2, Fig. 3,
Figures 4, 5 and 6 are side views of the forming station in different operations. 1... Circular table, 2... Molding station, 3
...Plasticization and injection unit, 4. Mixing device, 5.
...Guide, 6, 8, 9.12...Beam, 7...
Notch, 10... Pin, 11... Mold part holder, 1
3... Mold holding cylinder, 14... Plate, 15...
... Traveling cylinder, 16... Piston Rondo, 17.
... Mold part, 18... Cavity, 19... Heating block, 20... Heat insulation plate, 21... Cooling plate, 22... Mold part, 23... Cavity, 24
．． 25...Mold part for side molding, 26...Shoe last, 27
...Shoe shaft, 29...Shoe last receiving part, 30...
Pin, 31...Shoe mold rotating body, 32...Punch, 33
... plate, 34 ... passage, 35 ... hole

Claims (1)

[Scope of Claims] 1. A molding station for integrally molding a sole with an elastomer sole and an intermediate sole made of a mixture of isocyanate and polyol completely reactive with polyurethane onto a shoe shaft, comprising: In this case, the intermediate sole and the sole are connected to each other by a chemical bond between the isocyanate and the substance added to the reactive end groups of the elastomer, and the forming station is connected to a pivotably mounted mold part. a height-adjustable beam with a holder, the mold part holder having at least one holder for forming a shoe sole;
a second height-adjustable beam having a heatable plate disposed below the height-adjustable beam, the plate having a heatable mold part; The pivotable mold part holder cooperates with the heatable mold part of the pivotable mold part holder to mold the midsole, and the pivotable mold part holder is placed over the side mold part and the last to mold the midsole. In the version cooperating with a shoe shaft, a pivotably mounted mold part holder (11) is located on the side parallel to the second height-adjustable beam (12) of the sole. It has a mold part (17) which cooperates with the heatable plate (14) and has a mold part (17) with a cavity (18) for the heatable plate (14), and on the other side a cavity (2) for receiving the already molded sole.
3) with a mold part (22) cooperating with the lateral mold parts and the shoe shaft placed over the last, and with a pivotably supported mold part holder; Above, a height-adjustable last receiver (29) with a last swivel (31) is arranged, the last swivel (31)
includes a last (26) for the shoe shaft and a vacuum-loadable punch (26) for picking up the molded sole and delivering it after cooling into the cavity for the already molded sole. 32) A molding station comprising: 2. A molding station as claimed in claim 1, in which the mold part with the cavity can be applied with a vacuum for receiving the sole. 3. The molding station according to claim 1 or 2, wherein the mold part has a hole opening into the cavity.