JPH0117683B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to athletic shoes, particularly soccer shoes, having a sole and a protrusion integrally injection-molded on the inner sole, a method for manufacturing the athletic shoes, and a method for carrying out the manufacturing method. Regarding injection molds.

PRIOR TECHNOLOGY When manufacturing sports shoes with injection-molded soles and protrusions, the known method for integrally injection-molding the material into the shoe body (Federal Republic of Germany) is used as a general rule. Patent Nos. 2241493 and 2022118).

Furthermore, an injection mold is used which has a bottom press plate, optionally a corresponding press plate, a wooden mold and two side molding parts. In their closed position, the side moldings limit the penetrations for the bottom pressure platform and the corresponding pressure platform. The mold rests on the side molding parts which occupy the closed position after covering the body. In order to form a shoe sole in the space of the penetration limited by the side moldings occupying the closed position and by the bottom pressure plate and the corresponding pressure plate or mold with a covered body. Material is injected through the injection passage. The sole can be formed from an outer sole and an intermediate sole, each of which is formed in a special injection process.

Traditionally, in the production of sports shoes with injection molded soles and lugs, the lugs are first injection molded in a separate operation, and then the lugs are inserted into cutouts in a suitably formed bottom pressure pad. The bottom pressure plate then cooperates with the side molding parts and the wooden mold with the overlaid upper part, the protrusion being applied to the inner sole of the sports shoe or shoe to be produced.

In general, soccer shoes or soccer boots have at least three types of projections, which have heretofore had to be inserted into cutouts in the bottom pressure base using extremely tedious manual operations. Similarly, in the past, it was troublesome to stock such protrusions.

The invention is based on the fact that the sole and the lugs are produced and connected to the upper or the inner sole in one operation, without the complicated operations of producing, stocking and inserting the lugs.

The object of the invention is to provide an athletic shoe of the type mentioned at the outset, which has a sole and a projection molded in one piece.
In particular, the object is to improve the footwear so that the protrusions of the athletic shoe can be formed at the same time and integrally formed on the inner sole.

In the present invention, "stucker shoes" also refer to "satsuka boots," and athletic shoes that normally have a sole and a protrusion that are integrally injection-molded on the inner sole.
It is a pair of athletic shoes with protrusions that are similar to those in the case of footwear. Furthermore, according to the invention, a projection also refers to a region of the shoe sole which is connected in the same manner as a projection to the inner sole or to the trunk.

The above-mentioned problem is solved in the athletic shoes according to the present invention.
The sole of the shoe has a notch that reaches the inner sole,
This problem is solved by integrally injection molding the protrusion with the inner sole in the area of the notch.

With the sports shoe according to the present invention, there is no need to stock the protrusions, and there is no need to prepare protrusions of different sizes. A further significant advantage is that a power-conducting connection is obtained between the projection and the inner sole as well as between the projection and the region of the sole surrounding the projection.

A further object of the present invention is to provide a method for manufacturing such athletic shoes, especially soccer shoes.

Therefore, according to the manufacturing method of the present invention, the sole having the notch for the protrusion is integrally molded on the inner sole in the first injection molding stroke, and the protrusion is formed and the notch is formed in the second injection molding stroke. The inner sole is integrally molded within this range.

In another manufacturing method of the present invention, a protrusion is formed and integrally molded on the inner sole in a first injection molding stroke, and a sole is formed surrounding the protrusion in a second injection molding stroke, and the protrusion is integrally molded on the inner sole. It was made to be molded in one piece.

Furthermore, an injection mold for carrying out the manufacturing method according to the present invention includes two side molding members, a wooden mold, and a bottom portion having a protruding molded part whose shape is adapted to the protrusion for integrally injection molding the sole of the shoe. It has a pressure table and a bottom pressure table with a recess molding part for injection molding the protrusion, and the bottom pressure table is configured such that the casting can be taken out after injection molding. has been done.

When carrying out the method of the invention, a bottom pressure plate is first used which is provided with a molded protrusion adapted in shape to the projection, so that in the first injection molding stroke the sole with the recess for the projection is formed. A bottom pressure platform is used with a recessed mold that is formed and then used to mold the protrusion.

In a further implementation of the method according to the invention, a bottom pressure table with a recess molding section is first used to integrally mold the protrusion on the inner sole, and in a second injection molding stroke the shape of the protrusion is adjusted. A bottom pressure platform with a recessed molding adapted to this is used.

According to an embodiment of the injection mold of the present invention, the bottom press base for integral injection molding of the shoe sole has a central injection passage in the longitudinal direction of the shoe sole,
In this case, starting from the central injection channel, a tapered injection channel is opened on the sole of the shoe. In an extremely simple case, this tapering injection passage
The tapered injection passage branches off from the central injection passage such that its axis is perpendicular to the axis of the central injection passage. Due to the tapering of the injection channel starting from the central injection channel, it is possible to easily remove the casting from the bottom pressure plate by hand, for example using tools (pliers).

According to another embodiment of the injection mold according to the invention, a bottom pressure table is provided in order to be able to remove the casting from the bottom pressure plate in order to injection mold the protrusion in one piece after the injection molding stroke. It has a central injection passage extending in the longitudinal direction of the bottom surface of the calyx and a passage section that branches and extends at the plane of the injection passage, and is divided into two parts at the central injection passage and the central plane of the branched passage section. In this case, starting from the channel section, an injection channel is opened which tapers into the wall of the recess profile. By dividing the bottom press plate for integral injection molding of the protrusion into two parts, the formed casting can be easily removed from the bottom press plate after the injection molding stroke for producing the protrusion. Both parts of the bottom pressure platform can be separated from each other so that

For this purpose, in an embodiment of the injection mold, one part of the two-part bottom pressure plate has a pin with a stop for guiding the other part, in which case both parts A compression spring is placed on the pin between. With such an embodiment, after the pressure acting on the bottom pressure plate is removed, the 2
Both parts of the bottom pressurizing table, which is divided into parts, are automatically separated from each other so that the casting can be easily taken out.

According to a further embodiment of the injection mold according to the invention, the side molding part has a step as a support for the two-part bottom press plate. With this embodiment, the bottom pressurizing table for integral injection molding of the protrusion is brought into contact with the step part, and the hydraulic pressure acting on the bottom pressurizing table divided into two parts is reduced. In this state, both parts can be separated from each other and the other part can be brought into contact with the step part as a support member.

According to the invention, therefore, at the same time a method is provided for removing the casting produced when injection molding a projection from an injection mold, in which the mold is divided into two parts after the projection has been formed. The hydraulic load on the bottom press plate is reduced and the two-part bottom press plate is divided and the casting is released for removal.

EXAMPLE A device for manufacturing sports shoes has a number of working stations 1 arranged in a circle, each working station having a stationary part fixed to a stationary machine table 2 and a stationary part fixed to a stationary machine table 2 along the circumference. It consists of a rotating part (see Figure 2). The rotating part is fixed to a generally cylindrical mechanical structure rotatable about an axis 4 relative to a stationary mechanical table. The periodic motion is controlled by a step motor. The material for the sole of the shoe is injected into the shoe body at a working station by means of an injection molding unit 5 and the material for the projection by an injection molding unit.

FIG. 2 shows a section of FIG. 1, so that like components have been given the same reference numerals. The stationary part of the working station 1 consists of two side profiled parts, the separating plane of which lies in the plane of the drawing. Of the two side profiled parts, only the side profiled part 7 located behind the drawing plane is shown in the drawing. The side profiled parts are designed mirror-symmetrically with respect to the drawing plane and limit the penetration in the closed position in which they touch each other in the drawing plane. In this embodiment, the side moldings additionally limit a cutout in the closed position, which cutout is used for the attachment of one or more bottom pressure plates provided for carrying out the method of the invention. accepting the department.

A hydraulic working cylinder 10 is flange-connected to the machine frame 3 by means of a gusset plate 9, and a piston rod 11 of this working cylinder
are screwed to the bottom pressurizing tables 12, 19 of the injection mold. The circularly rotatable working station part has a carriage guide 13 in which a rotating part 15 of truncated conical construction about a pin 14 is arranged, and this rotation Two wooden molds 16 and 17, each of which is fitted with a body 18 of the shoe, are flanged to the part 15. In a first injection molding stroke, a shoe sole with a notch is injection molded onto the shoe body, which is placed on the side molding parts and placed over the wooden mold 17, using the bottom pressurizing table 19. . The protrusion is integrally formed with the bottom pressurizing table 12. When carrying out the method according to the invention, first of all a shoe sole with a notch is formed.
The protrusion is then injection molded by the injection molding unit 6 by replacing the bottom pressure table 19 with the bottom pressure table 12. If first the protrusion and then the sole are injection molded, the injection molding unit 5
first the protrusion and then the injection molding unit 6
The sole of the shoe is injection molded.

FIG. 3 schematically shows a bottom press 19 for integrally molding the sole on the body of the shoe in a sectional view through the plane of separation of the side moldings. Also, the same constituent members are denoted by the same reference numerals. The bottom pressure plate 19 has a central injection passage 20 that is aligned with the injection passages of the side moldings. The bottom pressurizing table has a protruding molded body 2 that comes into contact with the inner bottom of the body 18 of the shoe.
1. The hollow space defined by the side moldings, the inner sole, the bottom pressure base and the through-holes is used to mold a shoe sole having a notch formed to match the shape of the protruding molded body 21. It will be done. For this purpose, a further injection passage 22 extends from the central injection passage, which injection passage 22 is tapered and opens into a bottom pressure base forming a bottom tread. Due to the tapered shape of the injection channel 22, a tear-off edge 23 is formed at the edge of the opening of the injection channel, and the tear-off edge allows the casting to be removed from the bottom pressure plate. When the kimono is removed, the casting is torn off at this tearing edge. Bottom pressure table 19
In this embodiment, it has an extension 8 which projects in the working position into a shaped recess formed by the side moldings in the closed position.

FIG. 4 shows a cross-sectional view of the bottom pressing table 12 for manufacturing and integrally molding the protrusions after manufacturing the sole. The bottom pressure table 12 has a central injection passage 28 and is divided into two parts,
In this case, the separating plane extends through the axis of the central injection channel 28. Therefore, the bottom pressurizing table 12 has 2
It consists of two parts 29 and 30. A dosing channel section 27 branches off from the central dosing channel at right angles, the axis of which is located in the separation plane together with the axis of the central dosing channel. part 29
The recess 33 has a recess 33 whose shape is adapted to the projection to be formed. The recessed part 33 has an injection passage section 2.
A tapered injection passage 31 branching from 7 is guided. The injection channels each form a tearing edge 32, so that when the casting is withdrawn, the tapering casting section is torn off in the area of this tearing edge.

In FIG. 5, the bottom pressure plate is shown in an expanded position for drawing out the casting. A shoe sole and a protrusion are integrally molded on the shoe body, and the protrusion has a form-fitting and/or
Forms a power-conducting connection. The bottom pressure plate, as already illustrated in FIG. 4, consists of two parts, both of which are shown in the expanded position in FIG. 5 after injection molding of the projections. There is. In this case, the tapering injection channel likewise opens into the recess profile forming a tear-off edge. The casting is torn off by applying a tensile force to the entire casting in the direction of the arrow. part 29
pin 3 with one pin head 35 each
It has 4. A part 30 of the bottom pressure plate is movably guided along a pin 34, the pin head serving as a stop. Pins are arranged with compression springs in matching blind holes 25, 26 in both parts 29, 30. In the working position, i.e. after the bottom pressure plate has been moved into the penetration, the two parts are pressed together against the spring force of the compression spring, the bottom pressure plate being pressed against the shoulders of the side profiled parts. comes into contact with.

After the bottom pressurization platform has been removed from the penetration, both parts are widened to a maximum distance. In this case, this distance is larger than the diameter of the casting formed in the central injection channel, into which the casting corresponding to the injection channel section is molded in one piece. A tear-off edge formed in the casting in the injection channel by applying a tensile force in the direction of the arrow on the basis of the maximum distance created between the two parts (such as corresponds to the diameter of the central injection channel) It can be torn off from the projection and the entire casting can be removed from the bottom press via the formed gap.

FIG. 6 shows a cross-sectional view of a sports shoe manufactured by the method according to the invention. In this case, reference numeral 18 indicates the trunk, reference numeral 36 indicates the sole, and reference numeral 37 indicates the protrusion. As is clear from FIG. 6, the sole, the projection and the inner sole 24 form a form-locking and/or force-fitting connection.

Choosing soccer shoes for a particular sport is related to the conditions of the playing field. It is desirable to reduce or increase the flexibility of the sole as required. In the past, competitors randomly selected from a large number of existing race car boots. In this case, the soles of known soccer boots were suitable as long as they had a slight or great overall flexibility.

The invention is based on the fact that the best adaptation is achieved if the sole has a different flexibility in its individual regions. This reduces the number of soccer boots that need to be prepared for selection. A similar problem occurs with other types of shoes as well. Therefore, shoes that ensure comfortable walking in the area of footpaths often have a disadvantageous effect on hiking trails and the like.

The invention is based on the realization that such shoes can be made particularly well suited for comfortable walking and/or hiking by varying the flexibility of the sole in the individual regions. There is.

It is therefore an object of the invention to also provide shoes, in particular sports shoes (for example soccer boots), whose soles have different degrees of flexibility in individual regions.

Therefore, in a shoe according to the invention with a sole (having an intermediate sole and an outer sole) made of an injection moldable material integrally molded on the shoe barrel, the outer sole is integrally molded on the intermediate sole. It is made up of individual sections that are distinct from each other.

This gives flexibility to the sole by means of the intermediate area between the sections of the outer sole.

Therefore, in particular, by suitably designing the sections and intermediate areas, the foot movement during walking takes place naturally, i.e. starting from the heel, the foot follows the contour of the foot and along the toe area. You will be able to move in the direction of your thumb.

If the sole is injection molded, the material of the midsole can extend into the plane of the sections, so that dirt does not accumulate between the sections.

Additional fashionable effects can be obtained by suitably selecting the material for the sections, which can be injection molded from a material of a different color than the intermediate sole. The colors for the sections of the intermediate sole and the outer sole can thus be matched to each other in order to harmonize with the current fashionable colors of the covering.

For soccer boots with projections, one projection is injection molded together with the intermediate sole and integrally molded into the inner sole of the soccer boot, and the other outer sole with projections is injection molded and these projections are integrally molded into the inner sole of the soccer boot. At least some of the inner sole of the body is formed integrally with the inner sole of the body portion through a notch in the intermediate sole.

According to the invention, the integral molding of such a sole on the body of a soccer boot is achieved by forming in a first injection molding stroke one protrusion and an intermediate sole with a cutout for the other protrusion. integrally molded to the inner sole, and in a second injection molding stroke surrounding said one protrusion to form an outer sole section integrally molded to the inner sole and simultaneously forming the other protrusion;
(unless the protrusion is connected only to the section),
The notch area of the intermediate sole provided for the protrusion is integrally molded with the inner sole.

According to the invention, the injection mold for carrying out the method described above comprises two side molding parts;
It has a wooden mold, a first bottom presser, and a second bottom pressurizer, and the first pressurizer has an intermediate bottom, a protrusion thereof, and a notch for the protrusion of the section. a recess molded portion adapted in shape to the intermediate sole and its protrusion, and a protrusion molded portion adapted in shape to the protrusion of the section; the platform is used for injection molding the section and its protrusion together and has a recessed molding adapted in shape to the section and its protrusion;
and the two bottom pressurizing tables each have a central injection passage and are divided into two parts at the midplane of the central injection passage, and starting from the respective central injection passage, separate An injection passage opens into the depression molding.

The injection mold thus has two bottom pressure stations constructed according to the invention. According to the invention, therefore, in a first injection molding stroke, an intermediate sole with a projection on the inner sole (the projection forms a unit with the intermediate sole) is injected, and in this case at the same time (the projection forms a unit with the inner sole). Cutouts are provided for the projections of the sections (if connected).

FIG. 7 shows a shoe 40 having a shoe body 41 and an intermediate sole 42 in a perspective view. Molded on the intermediate sole is an outer sole 43 consisting of sections 44-50, which are separated from each other by zones 51-57 of the material of the intermediate sole.

As is clear from FIG. 7, the zones and the sections coincide, ie are located in one plane. Furthermore, the thickness of the zone can be made thinner than the thickness of the sections, so as to give shape to the entire sole.

By suitably designing the sections and their spacing as well as the length and width of the bands, and by suitably choosing the material properties of the intermediate and outer sole sections, the flexibility of the sole can be adjusted over a wide range. Can be adapted to the field of use. Thus, for example, simply by combining the material properties in different ways, shoes that were previously used only as street shoes can also be used as hiking shoes in mountainous areas, for example by means of different material combinations. As such, the flexibility can be adjusted.
Therefore, it is not necessary to use a separate injection mold for shoes of the same size for walking in mountainous areas. Additionally, the thickness of the sections can be varied to provide flexibility.

FIG. 8 shows, in a perspective view, a soccer boot 60 having a shoe body 61 and an intermediate sole 62. The intermediate sole 62 has sections 63, 64 of the outer sole 66,
65 is integrally molded. The section has a protrusion 67 provided on itself and a protrusion 68 made of the material of the intermediate sole.
is molded. Additionally, categories 63, 64,
A protrusion 69 is provided in the zone separating the 65 from each other.

FIG. 9 schematically shows a sectional view of a bottom press plate for integrally molding a midsole with projections on the body of a soccer boot through the separating plane of the side moldings.

Since FIG. 9 is a sectional view through the plane of separation of both side molding members, only one side molding member 71 is shown. The side moldings guide the bottom pressure platform 70 in their closed position. Bottom pressure table 70
has recessed molded parts 72 and 73 whose shape matches the intermediate sole and its protrusion, and a protruded molded part 74 whose shape matches the protrusion of the outer sole, and the protruded molded part 74 is formed on the body part of the soccer boot 76. It is attached to the inner bottom of 75. The bottom pressing platform 70 is divided into two parts in the plane of a central injection channel 77 for injecting the material for the intermediate bottom and its projections. Said plane extends through the axis of the injection channel 77 and is located perpendicular to the plane of the drawing.

In this plane extends the axis of an injection channel section 78 starting from the central injection channel, from which an injection channel 79 which tapers off in a tapered manner branches into the concave moldings 72, 73. It's open. The bottom pressurizing table 70 is composed of a lower bottom pressurizing table portion 70a and an upper bottom pressurizing table portion 70b.

The bottom pressure platform section has aligned blind holes 80, 81 and a compression spring 82 located on the pin.

In the position shown in FIG. 9, the side moldings are in the closed position. On the shoulder 83 of the side molding part a bottom pressure plate rests and, together with the molded upper part of the soccer boot, delimits the mold cavity for injecting the material for the intermediate sole and its protrusion.

After forming the intermediate sole and the protrusion, the bottom pressure platform is released. In this case, the compression springs 82 cause the bottom pressure plate portions to be spread apart, so that the entire casting can be taken out from the bottom pressure plate 70.

The bottom press 70 is replaced by a bottom press 85 for forming sections and protrusions and this bottom press is brought to the position shown in FIG.
As is clear from FIG. 10, the bottom pressure base 85 has a lower bottom pressure base portion 85a, an upper bottom pressure base portion 85b, blind holes 80, 81, and a compression spring 82.

In FIG. 10, the midsole is designated 86 and its protrusion is designated 87.

The bottom pressurizing table 85 has a recess molding part 8 whose shape is adapted to mold the sections and their protrusions.
It has 8.89. The depression is connected to a central injection channel 77 via a tapering injection channel, the axis of which extends through the separating plane of the bottom pressure platform portions 85a, 85b.

After injecting the material for the section and its protrusions, the bottom pressure platform 85 is released. Since the bottom pressurizing table part is expanded by the spring force, the casting can be taken out.

The fabrication of a shoe with an intermediate sole and an outer sole divided into sections can be carried out according to FIG. 9 and FIG.
This can be carried out by means of a bottom pressurization table suitably divided into two parts according to FIG.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a device for integrally molding the sole and protrusion of an athletic shoe, Figure 2 is a partial view of Figure 1 showing the work station, and Figure 3 is for manufacturing the sole. Cross-sectional view of the bottom pressurizing table, No. 4
The figure is a cross-sectional view of the bottom pressurizing table for making protrusions.
FIG. 5 is a view showing the bottom pressure base of FIG. 4 in an expanded position, FIG. 6 is a sectional view of the sports shoe, and FIG. 7 is a perspective view of the shoe having an outer sole and an intermediate sole divided into sections. 8 is a perspective view of a soccer boot having an outer sole and an intermediate sole divided into sections, and FIG. 9 is a perspective view of a bottom pressurizing platform divided into two parts for forming an intermediate sole and its protrusion. FIG. 10 is a cross-sectional view of a bottom pressing table for forming the outer sole protrusion on the outer sole sections and the intermediate sole. 1... Work station, 2... Machine table, 3... Machine frame, 4... Axis line, 5, 6...
... Injection unit, 7, 71 ... Side molded member, 8
...Additional part, 9...Gusset plate, 10...
Working cylinder, 11...Piston rod, 12,
19,70,85...Bottom pressure table, 13...Carriage table guide, 14...Pin, 15...Rotating part, 1
6, 17... wooden pattern, 18, 41, 61, 75...
Torso, 20, 22, 28, 31, 77, 79...
Injection passage, 21, 74... Protrusion molded part, 23, 3
2...Tear-off edge, 24...Inner bottom, 25,2
6... Hole, 29, 30... Part, 33, 72, 7
3, 88, 89... hollow molded part, 34... pin, 35... pin head, 36... shoe sole, 3
7, 67, 68, 69, 87... protrusion, 40...
Shoes, 42, 62, 86... Middle sole, 43, 66
...Outer bottom, 44, 45, 46, 47, 48, 4
9, 50, 63, 64, 65...Category, 51, 5
2, 53, 54, 55, 56, 57... Band, 6
0,76...Satsuka boots, 70a, 70b,
85a, 85b...Bottom pressure table part, 27, 78
... Injection passage division, 80, 81 ... Blind hole, 82 ...
...Compression spring, 83...Shoulder.

Claims (1)

[Claims] 1. In a pair of exercise shoes having a shoe sole and a protrusion that are integrally injection molded on the inner sole, the shoe sole 36 is attached to the inner sole 2.
A shoe sole integrally injection-molded on the inner sole, characterized in that it has a notch reaching up to 4, and the protrusion 37 is integrally injection-molded on the inner sole in the area of the notch. Athletic shoes having protrusions. 2. In the first injection molding stroke, a shoe sole having a notch for a protrusion is integrally molded on the inner sole, and the second injection molding stroke
A method for manufacturing athletic shoes having a shoe sole and a protrusion that are integrally injection molded on the inner sole, characterized in that the protrusion is formed with an injection molding stroke and the protrusion is integrally molded on the inner sole within the range of the notch. 3. In an injection mold for manufacturing athletic shoes having a shoe sole and a protrusion that are integrally injection molded on the inner sole, the injection mold has two side molding members 7,
It is equipped with wooden molds 16 and 17, a bottom pressurizing table 19 equipped with a protrusion molding part 21 whose shape matches the protrusion for integrally injection molding the sole of the shoe, and a recess molding part 33 for injection molding the protrusion. The injection molding device is integrally formed with the inner bottom, and has a bottom pressurizing table 12, and both bottom pressurizing tables are configured so that the casting can be taken out after injection molding. An injection mold for manufacturing athletic shoes having a sole and a protrusion. 4 A bottom pressurizing table 19 for integrally injection molding the sole of the shoe is located in the central injection passage 2 in the longitudinal direction of the sole of the shoe.
4. The injection mold according to claim 3, wherein an injection passage 22 having a diameter of 0 and opening from this central injection passage tapers to the bottom surface of the shoe. 5. The bottom pressurizing table 12 for integrally injection molding the protrusion has a central injection passage 28 extending in the longitudinal direction of the bottom surface of the shoe and a passage section 27 branching and extending in the plane of this injection passage, and An injection channel 31 which is divided into two parts in the midplane of the injection channel and the branched channel section and which tapers off from said channel section into the wall of the recess molding.
The injection mold according to claim 3, wherein the injection mold is open. 6. One part 29 of the bottom pressure base 12, which is divided into two parts, has a pin 34 with a stopper 35 for guiding the other part 30, and
Injection mold according to any one of claims 3 to 5, characterized in that a compression spring (82) is arranged on the pin between both parts. 7. The injection mold according to claim 6, wherein the side molding member has a stepped portion as a supporting member for a bottom pressurizing table which is divided into two parts. 8. The injection mold has two side molding members 71, a wooden mold, a first bottom pressing table 70, and a second bottom pressing table 85, and the first bottom pressing The base includes the intermediate bottom 62, 86, its protrusion 68 and the outer bottom section 6.
Hollow molded parts 72, 73 which are used for integrally injection molding the notches for the protrusions 67 of Nos. 3, 64, and 65 and which are adapted in shape to the intermediate sole and its protrusions; Protruding molded part 74
and a concave molding portion 88 whose shape is adapted to the section and its protrusion, and the second bottom pressurization table is used to integrally injection mold the section and its protrusion; 89, and both bottom pressurizing tables each have a central injection passage 77.
and 2 in the midplane of the central injection passage.
4. An injection mold as claimed in claim 3, which is divided into parts and in which the injection channel opens into the recessed part starting from the central injection channel of each part.