FR2678491A1 - METHOD FOR MANUFACTURING A CONTOUR PLATE FOR OVERMOLDING INSOLES ON SHOE RODS. - Google Patents

Abstract

The invention relates to a method of manufacturing a contour plate which constitutes, with two lateral mold elements, a bottom punch and at least one shape, a device for the overmolding of soles on shoe uppers, the soles comprising an outsole, a mounting sole and a midsole connecting the outsole to the mounting sole. A first operation consists in producing a blank of the contour plate (2), an operation followed by the finishing of the contour delimiting the mold cavity (15) for the wear sole, after which a layer with an outline delimiting the imprint mold (16) for the mounting flange is applied with the tool on the blank.

Description

The invention relates to a method for overmoulding soles on

  Ties of shoes, soles comprising a sole, a sole and a sole

  intermediary connecting the outsole to the first sole

  and a shoe mold (tool) for the implementation of

process.

  In the context of the invention, footwear rods are to be understood to mean prefabricated shoe rods made of leather, textile material, elastomer and thermoplastics, and shoe rods made before molding and assembly. soles, in the tool called shoe mold, and on which are then

molded soles.

  The term shoe stems further refers to

  in the context of the invention, shoe stems constitute

  thermoplastic material and made, 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

  footwear also refers to the usual shoe

  shoes, boots and boots, sports shoes, football boots, boots in general,

  same as shoes and work 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

  lyol transforming by polyurethane reaction

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

  abrasion resistant material.

  The abrasion resistant material generally

  the disadvantage that it is virtually devoid of

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

  spine This is why such mono soles

  layers are preferably provided for shoes and

work boots.

  To obtain a damping effect of the soles of shoes, it is known to provide between the outsole and the upper of the shoe a midsole whose abrasion resistance is, admittedly, low but which has good qualities. elasticity and damping, which is why it is also referred to as a comfort sole.

  These intermediate soles well known by the se-

  two layers, are hereinafter referred to as soles of

  because they establish the connection between the outsole and the rod In the following, this mounting plate

  can also be made in a non-damper material.

  Rubber two-layer soles are known

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

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

  mounting, an outsole made from a

  abrasion-resistant fabric that is resistant to wear but

  the damping effect is low or practically nil.

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

  framed by the color of the material introduced last.

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

  by the outsole and the bottom of the stem.

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

the mounting sole.

  In addition, it is known (DE-A-2,022,118) to produce two-ply soles from isocyanate and polyol mixtures which are converted by reaction into polyurethane by overmolding in a first step an insole 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 converted by reaction into

  lyurethane, to first make the outsole and

  Following the sole of comfort or mounting in a space in-

  intermediate formed between the outsole and the riser

on Form.

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

considered sole layer.

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

mounting.

  Tools for making shoe soles

  footwear rods, called molds, have in the simplest case 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

  side, the milling forms an opening that delimits the-

  a mold footprint for the overmolding sole

on a shoe upper.

  The bottom punch is guided in a highly adjustable way

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

  shape and to be arranged on the side mold elements

  placed in the closed position defines the peripheral

  upper part of the mold cavity.

  The side mold members have groove-like recesses in their bearing surface which extend in the direction of movement of the bottom punch and form, in the closed position of the

  side mold, carrot channels through-

  which is brought the material necessary for the molding of the

  outsole and respectively the sole of montaae.

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

  to fit the shape for the shoe upper on a red head

  tative adjustable in height which still includes, in addition to the

form, a conjugate punch.

  For the molding of the outsole, the punch

  conjugate plunges into the opening and forms the upper periphery.

  mold cavity for the outsole, and during the molding of the outsole, the conjugate punch blocks the carrot channel for the arrival of material destined

  molding the mounting flange.

  After the arrival of the material for the sole

  of wear, the bottom punch is mounted in a predetermined amount

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

the midsole.

  As soon as the outsole is sufficiently hard, the side mold elements are spread apart, the rotating head is moved upwards and rotated so that the shape with the shoe shank is oriented towards the sole

  worn on the bottom punch.

  After the closing of the lateral mold elements, the rotating head is moved so that the rod of

  footwear is a superior periphery

  mold cavity for the sole of the mold.

to achieve.

  Through the carrot channel-for the se-

  the intermediate material is fed the material for the insole

intermediate or comfort.

  Then, the rotating head with the finished shoe is moved up and the finished shoe is removed

of shape.

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

  and swivel which is called pivoting bottom punch.

  The implementation of the conjugate punch and one of the

  bottom punches lead to the formation of a midsole

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

  to the realization of the mounting base.

  In this way, a three-layered sole is

  conformed on a shoe upper.

  In general, the outsole can be

  made with openings into which the ma-

  of the intermediate layer formed subsequently, so that

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

  where appropriate, areas of different colorations.

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

  two pairs of side wheel elements at different levels

one above the other.

  For molding of the mounting flange, the two side mold members of the first pair cooperate in the manner described above with a shoe shank mounted

  on a shape and with an outsole placed on a point

background.

  For the molding of the outsole, use is made of the two lateral mold members of the pair of lower side mold members which respectively have on their end faces facing the pair of upper side mold members a bent leg. In the closed position of the lower side mold members, the two bent limbs seal the passage in the direction of the upper side mold members and assume during molding of

  the outsole the function of a conjugate punch.

  During the molding of the outsole, the bottom punch cooperates with the lower side mold members

  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 side mold elements for molding the mounting flange. The tools with the training elements are

  grouped into work stations which are arranged by several

  in a row to form production lines or installed by several on turntables to form

  turntable installations.

  The production lines and turntable systems allow, in principle, manufacturing times

  rational for shoes, boots and the like.

  The invention is devoted hereinafter to overmolding soles on shoe uppers, the soles comprising a sole plate, a first mounting sole and an intermediate sole and the soles being constituted by a thermoplastic material or by a mixture of Isocyanate and

  of polyol being converted by reaction into polyurethane.

  The use of mixtures of isocyanate and

  lyol transforming by polyurethane reaction collides, as is known, with the difficulty that these mixtures have at the beginning of the mixing and also the transport in the mold imprints for the molding of the layers of soles (outsole, outsole mounting, midsole), so low viscosity that they penetrate into any

  which separation slot, for example in the separation plan,

  between the lateral mold elements, and also in the case where the elements of the molds and the tools respectively

  are made with extreme precision.

  That's why we use for the

  overmolding of soles made from mixtures of iso-

  cyanate and polyol converting by reaction into polyurethane

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

  bottom cups, that is to say, bottom punches that pre-

  feel a continuous rim and form a sort of

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

  a substance that is converted by reaction into polyurethane, the

  edge of the bottom punch is at a distance from the edge of the

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

  the bowl bottom punch placed in this free position

  the carrot channel so that the material to be introduced

  may be brought to said bowl bottom punch From

  that the bowl bottom punch has received a predetermined quantity

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

  blocks the carrot channel Since during the trans-

  formation by reaction of the mixture the viscosity increases, the reactive mixture can not be introduced after a certain

  time between the outer lateral surface of the rim of the

  bottom bowl and side mold elements.

  On the other hand, it is possible that the reaction mixture propagates at the beginning along the outer lateral surface of the rim of the conjugate punch. This is why the procedure is carried out in practice so that the processes are controlled from

  in such a way that the outer lateral surface of the rim of

  Conjugate is wrapped in a layer of reactive

  It is only after the molding of the outsole and the other sole layers and the overmolding of the soles on

the shoe stems.

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

  mounting or midsole, made from

  swaddling by polyurethane reaction, 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 stems soles with a

  outsole, a mounting flange and an insole

  mediate by using an additional conjugate punch

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

and especially for the order.

  According to the invention, this object is achieved by the fact that, in a first step, the outsole and the mounting flange are formed with two lateral mold elements, a bowl shaped punch and a shape provided with a shoe shank and placed on the side mold members in the closed position, and an insertable contour plate dividing the opening of the side mold members into two mold impressions, and that after removal of the contour plate, the midsole is made in a second step, with simultaneous overmolding on the sole

  wear and on the mounting flange.

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

  the sole are made from a thermoplastic material

  instead of mixtures of isocyanate and polyol which

  transform by reaction into polyurethane.

  In contrast to the current state of the art, the use of a bottom punch which is replaced by an edge plate whose dimensions are chosen so that it rests on the edge of the punch background in

  bowl and on the undercut of the side mold elements

  in the direction of the mold cavity for the outsole to be produced, a spatial outline

  corresponds to that of the outsole with the insole

  intermediate and, in the direction of the mold imprint for the

  footing, a spatial outline which corresponds to

  to that of the mounting flange with the inner sole

  the thicknesses and other dimensions of the plate

  outline being chosen so as to obtain, after its removal,

  a mold cavity with the dimensions of

  the midsole to achieve.

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

  deep modifications for the mold and for the control.

  The problem posed by the creation of a device for carrying out 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 contour plate which subdivides the opening of the side mold members into the closed position, into a mold cavity for the mounting flange and a mold cavity for the outsole and can be placed on the

  edge of the bottom punch in bowl.

  According to the invention, the contour plate has a continuous flange 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 flange corresponding to the dimensions of the midsole-

diaire-

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

  mune between the mounting flange and the midsole.

  To reduce this considerable work expense, the contour plate is provided, according to another embodiment of the invention, a layer of deformable material by the tool and having a surface structure adequate to take into account the dimensions of the mold imprint 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 by deformable material by the tool

  (the mold) so that it presents towards the se-

  mount the aforementioned dimensions.

  The invention also relates to a manufacturing process

  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 finishing of the contour delimiting the mold cavity for the outsole, after which a layer with a contour delimiting the mold footprint for the mounting flange is applied with the tool

on the sketch.

  The description that follows, next to the drawings

  annexed by way of non-limiting examples, will

  understand how the invention can be put into practice.

  Figure 1 shows, in perspective, a view of a bottom punch and an edge plate; Figure 2 shows a side view of the bottom punch and the contour plate of Figure 1; FIG. 3 is a schematic representation of the overmoulding of a sole plate and a mounting plate on a rod.

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

  of the lateral mold elements placed in the posi-

  closing arrangement, and FIG. 4 shows, in accordance with FIG.

  conformation of the midsole.

  Fig 1 shows, in perspective, a bottom punch

  in bowl 1 and a contour plate 2.

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

  with the contact surface of the outsole to achieve.

  The edge is raised and includes a bearing surface 5

  which corresponds to an edge extending in space and completes

  This edge serves to support the contour plate 2 with its continuous edge 6 when producing the outsole, that is to say that the bearing surface 7 of its edge 6 is supports

  on the complementary support surface 5.

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

the outsole to achieve.

  When producing the outsole and the mounting flange, the continuous edge 6 rests with its surface

  8 against the undercut of the lateral mold elements

  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, whose

  dimensions are consistent with the dimensions of the inner sole

to achieve.

  Fig 2 shows a side view of Fig 1.

  Identical elements bear the same references, the point

  of the bowl bottom punch being designated 10.

  3 schematically represents the molding of the outsole and the mounting flange, the plane of the drawing being oriented in the mutual application plane of the

  lateral mold elements placed in the closed position

  which only the lateral mold element situated

  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 bowl bottom punch 1, on the other hand-the carrot channels 13 and 14 which open into the mold cavity 15 and 16 respectively for the outsole and respectively for the mounting flange are

then released.

  The boot upper 18 mounted on the form 17 ensures

  sealing of the mold cavity for the sole of

  in the area of undercutting.

  According to FIG. 3, the contour plate consists of a plate which, inside the edge 6, has a suitable contour in the direction of the mold cavity 15 for the outsole and is provided with direction of impression

  mold 16 for the mounting flange, a layer of

  19 of the material for the outsole, whose contours are chosen so that the region of the

  an edge plate surrounded by edge 6 has the dimensions

  of the midsole to achieve.

  After the molding of the outsole and the

  the 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 the molding of the midsole is released (position of the bottom punch in Fig 4), forming a mold cavity 21

bigger.

  After the material for the midsole has been introduced, the cup bottom punch is moved upward until it abuts against the undercut 12 of the side mold members, so that the impression of mold 21 is reduced to the volume of the midsole and

  that the carrot channel 20 is closed After the reaction

  plete sole material, the shoe is removed from the

  well-known manner of

14 -

Claims (1)

CLAIM   A method of manufacturing a contour plate which, together with two lateral mold elements, constitutes a bottom punch and at least one shape, a device for overmolding soles on shoe rods, the soles comprising a sole plate , a mounting flange and a midsole connecting the outsole to the mounting flange, characterized in that a first operation consists in making a blank of the contour plate (2), operation followed by the finishing of the contour defining the mold cavity (15) for the outsole, after which a layer with a contour delimiting the mold cavity (16) for the sole   mounting is applied with the tool on the blank.