FR2675984A1 - METHOD AND DEVICE FOR OVERMOLDING SOLE ON SHOES UPPER. - Google Patents

Abstract

The overmolding on shoe uppers of soles comprising an outsole, a mounting sole and a midsole connecting the outsole to the mounting sole is carried out in such a way that, in a first step, the sole d The wear and the mounting sole are formed with two side mold members, a cup base punch (1) and a shape provided with a shoe shank and placed on the side mold members in the closed position, and a plate contour (2) insertable and dividing the opening of the side mold elements into two mold cavities. After removal of the contour plate, the midsole is made in a second step, with simultaneous overmolding on the outsole and on the mounting sole.

Description

Method and device for the overmolding of soles on rods

  The invention relates to a method for molding soles on shoe uppers, the soles comprising a outsole, a sole and a sole.

  midsole connecting the outsole to the pre-

  as well as a shoe tool mold) for setting

process work.

  With regard to shoe uppers, it is to be understood within the framework of the invention, prefabricated shoe uppers of leather, textile material, elastomer and thermopiastic materials as well as shoe uppers produced, before molding and assembly soles, in the shoe mold tool, on which are then

molded soles.

  The term shoe uppers further indicates,

  in the context of the invention, shoe uppers made up

  killed by a thermoplastic material and produced, for example, from plasticized granulated polyurethane, polyvinyl chloride, etc. or mixtures of isocyanate and polyol which

  transform by reaction into polyurethane.

  In the sense of the invention, the term rods of

  shoes also refers to the uppers of customary shoes

  tuelles for low shoes, uppers as well as the uppers of boots, sports shoes, football shoes, boots in general,

  same as work shoes and boots.

  In the context of the invention, the term “soles” means soles made of a thermoplastic material such as PVC or plasticized granulated polyurethane, as well as

  soles made from mixtures of isocyanate and polyurethane

  lyol transforming by reaction into polyurethane.

  In the simplest case, shoes, boots, etc. comprise an overmolded sole made of a single material, that is to say an outsole made from

  abrasion resistant material.

  The abrasion resistant material generally has-

  the downside is that it is practically devoid of pro-

  damping properties, so that when walking or running, shocks or jolts caused by uneven terrain are practically transmitted without damping to the

  spine This is why such mono- soles

  layers are preferably provided for shoes and

work boots.

  To obtain a damping effect on shoe soles, it is known to provide between the outsole and the upper of the shoe an intermediate sole whose abrasion resistance is, admittedly, low but which has good qualities of elasticity and cushioning, which is why it is also called the comfort sole.

  These midsoles well known by the se-

  two-layer insoles, hereinafter referred to as insoles

  because they establish the connection between the outsole and the upper In the following, this mounting sole

  can also be made of a non-shock absorbing material.

  Two-layer rubber soles are known

  (DE-A-2 048 596) which are overmolded on shoe rods

  safe in such a way that, in a first step, a mounting or comfort sole made of a mass of damping rubber is shaped and that a second step consists in then injection molding on this comfort sole or

  mounting, a outsole made from a material

  abrasion-resistant fabric that resists wear and tear but

  the damping effect is weak or practically nil.

  It is also known (DE-A-1 485 987) to overmold first of all, also in a first step, on a shoe upper a sole of comfort or mounting and then to introduce, in a second step , the material for the outsole in a recess created during the overmolding of said mounting or comfort sole, which is surrounded in the manner of a frame by the material of the comfort or mounting sole In the case of the use of materials of different colors, the outsole has a section

  framed by the color of the material last introduced.

  It is also known (DD-A-64 882) to first make the outsole with a lateral edge, to place on the upper periphery of the lateral edge the shoe upper mounted on a form and to inject the material for the mounting or comfort sole, through openings provided in the outsole, in the defined intermediate space

  by the outsole and the bottom of the upper.

  Likewise, it is known (also DD-A-64 882) to constitute from a piece of material, for example a rubber plate, an outsole and then form

the mounting base.

  In addition, it is known (DE-A-2 022 118) to make soles with two layers from mixtures of isocyanate and of polyol transforming by reaction into polyurethane by overmolding in a first step a sole of comfort or mounting. on a shoe upper and, in a second step, the outsole, after the complete transformation

polyurethane mixture.

  Furthermore, it is known (DE-A-2 241 493) for the manufacture of two-layer soles from mixtures

  of isocyanate and polyol transforming by reaction into po-

  lyurethane, first make the outsole and

  following the comfort or mounting sole in an uncluttered space

  intermediate formed between the outsole and the mounted upper

on Form.

  For the production of the two layers of sole, the reactive mixture is introduced in a suitable quantity into a cavity or mold cavity whose volume is greater than the volume of the outsole and respectively of the midsole These volumes are reduced , after the introduction of the respective reactive mixture, to the volume of the

sole layer considered.

  All these processes have in common the fact of making the harder and abrasion resistant sole first and only then forming the elastic sole layer, that is to say more flexible compared to the sole. wear, since the conformation of the outsole on a comfort or mounting sole already produced would have the effect of an uncontrolled compression and densification respectively of the softer material of the comfort sole or

mounting.

  The tools for making shoe soles

  safe on shoe uppers, called molds, in the simplest case have two lateral mold elements each of which has a countersink, a bottom punch and a

  form (DE-A-2 048 596, DE-A-1 729 141, DE-A-3 516 280).

  In the closed position of the mold elements

  lateral, the milling forms an opening which delimits the

  a mold imprint for the sole to be molded

on a shoe upper.

  The bottom punch adjustable in height

  in the opening constitutes the lower periphery of the mold cavity, and the shoe upper mounted on the

  form and to be arranged on the side mold elements

  in the closed position defines the periphery

  superior mold imprint.

  The lateral mold elements have, in their bearing surface, recesses in the form of grooves which extend in the direction of movement of the bottom punch and form, in the closed position of the

  lateral molds, carrot channels through-

  what material is brought in for molding the

  outsole and mounting sole respectively.

  In this embodiment of the mold, the separation surface between the mounting sole and the outsole and the surface of the outsole in contact with the ground are parallel and correspond to the spatial geometry of the surface of the punch. height adjustable bottom. It is also known (DD-A-64 882, DE-A-2 241 493),

  to mount the form for the shoe upper on a red head

  height adjustable tent which also includes, in addition to the

form, a conjugate punch.

  For molding the outsole, the punch

  conjugate plunges into the opening and forms the upper periphery

  lower the mold footprint for the outsole, and during the molding of the outsole, the conjugate punch blocks the core channel for the arrival of material intended

  when molding the mounting base.

  After the arrival of the material for the sole

  wear, the bottom punch is mounted by a predetermined amount-

  mined, after solidification of the outsole placed on said bottom punch, and blocks the core channel so as to prevent an additional material supply for

the midsole.

  As soon as the outsole is sufficiently hard, the lateral mold elements are moved apart, the rotating head is moved upwards and pivoted so that the shape with the shoe upper mounted is oriented towards the sole

  of wear placed on the bottom punch.

  After closing the side mold elements, the rotating head is moved in such a way that the rod

  shoe mounted on the form constitutes an upper periphery

  leak tight of the mold footprint for the sole of

tage to achieve.

  Via the carrot channel for the se-

  the intermediate material is brought in for the insole

intermediate or comfort.

  Then the rotating head with the finished shoe is moved upwards and the finished shoe is removed

of shape.

  Furthermore, molds are known with a rotating head which are provided with two bottom punches. The two bottom punches constitute a unit adjustable in height.

  and swivel which is called a swivel bottom punch.

  The implementation of the conjugate punch and one of the

  bottom punches leads to the formation of a midsole

  then, by replacing the bottom punch, to that of the outsole, and finally, by replacing the punch marked by the shape carrying the shoe upper,

  the production of the mounting base.

  In this way, a three-layer sole is

  shaped on a shoe upper.

  Generally, the outsole can be

  made with openings into which the ma-

  third of the intermediate layer formed next, so that

  the surface of the outsole in contact with the ground pre-

  if necessary, feel zones of different colors.

  It is also known (US-A-4,090,831) to have

  two pairs of side mold elements at different levels

rents one above the other.

  For the molding of the mounting base, the two lateral mold elements of the first pair cooperate in the manner described above with a shoe upper mounted

  on a form and with a outsole placed on a point-

basic lesson.

  For the molding of the outsole, the two lateral mold elements of the pair of lower lateral mold elements are used which have respectively on their front face directed towards the pair of upper lateral mold elements, a bent branch In the closed position of the lower lateral mold elements, the two bent branches close the passage in the direction of the upper lateral mold elements and assume during the molding of

  the outsole has the function of a combined punch.

  During the molding of the outsole, the bottom punch cooperates with the lower lateral mold elements

  in the closed position which are then brought into their po-

  opening position, so that the bottom punch can be brought, with the molded outsole, into the working position in which it can cooperate with the upper lateral mold elements for molding the mounting sole . The tools with the drive elements are

  grouped into workstations which are arranged by more

  sieurs in a row to form production chains or installed by several on turn tables to form

  turntable installations.

  Production lines and turntable installations allow, in principle, manufacturing times

  rational for shoes, boots and the like.

  The invention is devoted below to the molding of soles on shoe uppers, the soles comprising a outsole, a first assembly sole and a midsole and the soles being made of a thermoplastic material or of a mixture of isocyanate and

  of polyol transforming by reaction into polyurethane.

  The use of mixtures of isocyanate and of po-

  lyol transforming by reaction into polyurethane faces, as we know, the difficulty that these mixtures present at the start of mixing and also the transport in mold imprints for the molding of the layers of soles (outsole, sole first assembly, midsole), a viscosity so low that they penetrate into any

  which separation slot, for example in the separation plane

  ration between the side mold elements, also in the case where the mold elements and tools respectively

  are made with extreme precision.

  This is the reason why we use for the

  overmolding of soles made from mixtures of iso-

  cyanate and polyol transforming by reaction into polyurea-

  thane (DE-A-2 241 493) bottom punches called punches

  bottom to bowl, i.e. bottom punches that pre-

  feel a continuous edge and somehow form a cu-

  vette. On this rim, the conjugate punch is supported with a continuous rim, the bottom punch in a bowl and the conjugate punch which must in a way be qualified as a conjugate punch in a bowl delimiting, after mutual application of their rim, the mold imprint for the outsole. For the introduction into the mold imprint of the

  material transforming by reaction into polyurethane, the re-

  edge of the bottom punch is located away from the edge of the punch

  combined lesson, the two lateral mold elements placed in the closed position delimiting the core channel for the material to be introduced for the outsole to be molded, and

  the bottom punch in the bowl placed in this released position

  the carrot channel so that the material to intro

  can be brought to said bottom punch in a bowl From

  that the bottom punch in the bowl has received a predefined quantity

  finished in material, it is raised so that its rim comes into contact with the rim of the conjugate punch and it

  blocks the carrot channel Since during trans-

  reaction formation of the mixture the viscosity increases, the reactive mixture can no longer be introduced after a certain

  time between the outer side surface of the tip edge

  bottom bowl and side mold elements.

  On the other hand, it is possible that the reactive mixture propagates at the beginning along the external lateral surface of the rim of the conjugate punch. This is why one proceeds in practice in such a way that the processes are controlled by

  so that the outer side surface of the edge of the punch

  conjugated lesson is enveloped by a layer of reactive material

  tive, with the formation of a seal It is only after the molding of the outsole and the other layers of sole occurs and the molding of the soles on

shoe uppers.

  Hereinafter, a bottom bowl punch is also used in the case where the outsole and possibly the other sole layers are made of a thermoplastic material. When overmolding on shoe uppers a sole consisting of a outsole and a sole

  mounting or midsole, made from

  swaddles transforming by reaction into polyurethane, the molds or tools include a bottom punch, two elements

  side molds and a conjugate punch.

  According to the same principle, it is also possible to overmold on shoe uppers soles with a

  outsole, mounting sole and midsole

  medial using an additional conjugate punch

  to hush up. This results in a corresponding increase in the cost of the mold and the order for the mold becomes much more complicated. The object of the invention is to produce said mold for the molding of soles consisting of a wear sole and a midsole (mounting sole) on shoe uppers such that the molding of soles comprising a sole of wear, a mounting sole and a midsole on shoe uppers can be made without significant additional expense for the tool

and in particular for the order.

  According to the invention, this object is achieved by the fact that, in a first step, the outsole and the mounting sole are formed with two lateral mold elements, a cup-shaped punch and a shape provided with a shoe upper and placed on the lateral mold elements in the closed position, and a contoured plate which can be inserted and dividing the opening of the lateral mold elements into two mold cavities, and that, after the removal of the contoured plate, the midsole is produced in a second step, with simultaneous overmolding on the sole

  of wear and on the mounting base.

  The essential for the invention is the implementation of a bottom punch in a bowl which is used which is also essential for the invention even if the layers of

  the sole are made from a thermoplastic material

  tick instead of mixtures of isocyanate and polyol which

  transform by reaction into polyurethane.

  Unlike the current state of the art, the use of a bottom punch is dispensed with, which is replaced by an outline plate, the dimensions of which are chosen so that it rests on the edge of the punch. background in

  bowl and on the undercut of the side mold elements

  that it presents, in the direction of the mold imprint for the outsole to be produced, a spatial contour which

  matches that of the outsole with the outsole

  intermediate and towards the mold footprint for the

  mounting plate to be produced, a spatial contour which corresponds

  that of the mounting base with the inter-

  the thicknesses and other dimensions of the plate to

  contour being chosen so as to obtain, after its removal

  vement, a mold imprint which shows the dimensions of

  the midsole to be produced.

  This measure has the effect of allowing with a single mold for overmolding two-layer soles on shoe uppers, overmolding three-layer soles on shoe uppers, without requiring

  profound modifications for the mold and for the order.

  The problem posed by the creation of a device for implementing the method is solved by the fact that a device (mold, tool) comprising two lateral mold elements, a bottom punch and at least one shape, comprises in addition a contoured plate which subdivides the opening of the lateral mold elements in the closed position, into a mold imprint for the mounting base and a mold imprint for the outsole and can be placed on the

  edge of bottom punch in bowl.

  According to the invention, the contour plate has a continuous rim for pressing on the edge of the bottom punch and on the undercut of the lateral mold elements, the dimensions of the part of the contour plate surrounded by

  the rim corresponding to the dimensions of the midsole

  diary. In principle, the contour plate corresponds to a conjugate punch for which the conjugate punch plate remaining after the withdrawal of the punch receives, on the side of the punch, for example by the treatment of the material, a spatial contour which corresponds to that of the contact surface

  mune between the mounting sole and the midsole.

  To reduce this considerable labor expense, the contour plate is provided, in accordance with another embodiment of the invention, with a layer of material deformable by the tool and having an adequate surface structure to take account of the dimensions mold footprint for

the midsole.

  This measurement has the effect that, on the side of the contour plate directed towards the mounting flange, said contour plate is completed with material deformable by the tool

  (the mold) so that it presents in the direction of the

  mounting the aforementioned dimensions.

  The invention also relates to a method of manufacturing

  cation of the contour plate, which is characterized in that a first operation consists in making a blank of the contour plate, operation followed by the finishing of the contour delimiting the mold imprint for the outsole, after which a layer with a contour delimiting the mold imprint for the mounting base is applied with the tool

on the draft.

  The following description, next to the drawings

  appended as nonlimiting examples, will allow

  understand how the invention can be put into practice.

  Figure 1 shows, in perspective, a view of a bottom punch and a contour plate; 2 shows a side view of the bottom punch and the contour plate of Fig 1; Figure 3 shows schematically the overmolding of a outsole and a mounting sole on a rod

  shoe, the plane of the drawing lying in the plane of ap-

  folding of the lateral mold elements placed in the posi-

  closure, and Figure 4 shows, in accordance with Fig 3, the

  conformation of the midsole.

  Fig 1 shows, in perspective, a bottom punch

  in bowl 1 and a contour plate 2.

  The bottom bowl punch 1 has a surface 4 surrounded by the edge 3, the spatial outline of which coincides

  with the contact surface of the outsole to be produced.

  The edge is raised and includes a bearing surface 5

  which corresponds to an edge extending in space and complete-

closed.

  This edge serves as a support for the contoured plate 2 with its continuous edge 6 during the production of the outsole, that is to say that the bearing surface 7 of its edge 6 is supported

  on the complementary bearing surface 5.

  The region of the contour plate surrounded by the edge 6 presents in the direction of the outsole to be produced a contour of spatial extension which corresponds to the contour of the common contact surface of the midsole and of

the outsole to be produced.

  When making the outsole and the mounting sole, the continuous edge 6 rests with its surface

  support 8 on the undercut of the lateral mold elements

  rails placed in the closed position (fig 3).

  This completely closed edge 6 of the contour plate surrounds the spatial section 9 of the contour plate, the

  dimensions match the dimensions of the midsole

mediary to achieve.

  Fig 2 shows a side view of fig 1.

  Identical elements have the same references, the point-

  du of the bottom bowl punch being designated by 10.

  FIG. 3 diagrammatically represents the molding of the outsole and of the mounting sole, the plane of the drawing being oriented in the plane of mutual application of the

  side mold elements placed in the closed position

  ture of which only the lateral mold element situated below

  under the drawing plane is visible and designated by 11.

  The contour plate 2 bears with its edge 6 on the undercut 12 of the lateral mold elements on the one hand and on the edge 3 of the bottom punch in bowl 1, on the other hand. The core channels 13 and 14 which open into the mold cavity 15 and respectively 16 for the outsole and respectively for the mounting sole are

then released.

  The shoe upper 18 mounted on the form 17 ensures

  the tightness of the mold footprint for the sole of

  tage in the region of the undercut.

  In accordance with FIG. 3, the contour plate consists of a plate which, inside the edge 6, has an adequate contour in the direction of the mold imprint 15 for the outsole and is provided, in footprint direction

  mold 16 for the mounting base, a layer of material

  face 19 made of the material for the outsole, the contours of which are chosen so that the region of the

  contour plate surrounded by the edge 6 has the dimensions

  sions of the midsole to be produced.

  After molding the outsole and the shoe

  mounting plate which is overmolded at the same time on the shoe upper, the contour plate is removed manually or by means of a claw, so that, in accordance with FIG. 4, the core channel 20 for the material intended for molding of the midsole is released (position of the bottom punch in fig 4), forming a mold imprint 21

bigger.

  After the introduction of the material for the midsole, the bottom punch in the bowl is moved upwards until it abuts against the undercut 12 of the lateral mold elements, so that the imprint mold 21 is reduced to the volume of the midsole and

  that the carrot channel 20 is closed after the reaction

  full of sole material, the shoe is removed from the

  well-known way of form.

14 2675984

Claims (4)

  1 Method for overmolding soles on shoe uppers, the soles comprising a outsole, a mounting sole and a midsole connecting the outsole to the mounting sole, characterized in that, in a first step, the outsole and the mounting sole are formed with two lateral mold elements, a bottom punch in a bowl and a shape provided with a shoe upper and placed on the lateral mold elements in the closed position, and a contour plate that can be inserted and dividing the opening of the lateral mold elements into two mold cavities, and that, after the removal of the contour plate, the midsole is produced in a second step, with simultaneous overmolding on the   outsole and on the mounting sole.   2 Device for implementing the method according to claim 1, comprising two lateral mold elements, a bottom punch and at least one shape, characterized in that it comprises, in addition, a contour plate (2) which subdivides the opening of the lateral mold elements (11) in the closed position, into a mold imprint (16) for the mounting base and a mold imprint (15) for the outsole and can be placed on the edge (3) of bottom punch in bowl (1) -   3 Device according to claim 2, characterized in that the contour plate (2) has a continuous edge (6) for pressing on the edge of the bottom punch and on the undercut of the lateral mold elements (11) , and that the dimensions of the region (9) of the contour plate surrounded by said edge correspond to the dimensions of the midsole. 4 Device according to claim 3, characterized in that the contour plate is provided with a layer of deformable material having an adequate surface structure to take account of the dimensions of   the mold footprint for the midsole.