JP5000524B2 - Soles and shoes - Google Patents

Description

  The present invention relates to a shoe sole exhibiting high slip resistance performance against a floor surface wet with water or oil, a shoe using the shoe sole, a method for molding the shoe sole, and the like.

Conventionally, the technique of patent document 1 is known regarding the shoe sole which uses a polyurethane foam etc.
JP 2000-201704 A

The shoe sole described in Patent Document 1 is described as being a shoe sole that has excellent anti-slip properties and at the same time has a feature that raw material residue or the like is not easily clogged in the groove of the shoe design. However, although it is excellent in slip resistance, it is unclear how much slip resistance is achieved.
The present invention is high in the slip resistance measurement described in the safety shoe technical guideline which is the technical guideline of the Industrial Safety Research Institute, which is said to have high slip resistance if the dynamic friction coefficient exceeds 0.2 (in the same measurement result) It is an object of the present invention to provide a shoe sole and a shoe having a slip resistance (dynamic friction coefficient of about 0.3 or more).

In order to solve the above-mentioned problems, the invention described in claim 1 of the present application has the following configuration. That is,
A shoe sole having an outsole formed by molding a foamable material such as a midsole and polyurethane foam,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
In the outsole, at least on the center of the forefoot region and the center of the buttock region, a plurality of central grounding blocks having a polygonal grounding surface of a quadrangle or a shape similar to the quadrangle along each center, A plurality of left and right grounding blocks having a quadrangular or polygonal grounding surface in a shape approximating the quadrangle is provided at a position separating the central grounding block and a vertical groove having a predetermined width,
The angle formed by the side surface of each grounding block and the grounding surface is substantially a right angle,
The center grounding block and the left and right grounding blocks provided in the forefoot sole region are provided alternately so as to be displaced by about half of the length in the front-rear direction, and the lateral grooves that define the front-rear direction of each grounding block are: A groove that is bent in a crank shape is formed with the longitudinal groove,
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that.

The invention described in claim 2 is characterized by having the following configuration. That is,
The shoe sole according to claim 1, wherein the outsole has a hardness of 55 to 85 as measured by a spring type C-type hardness meter in accordance with JIS K7312.

The invention described in claim 3 is characterized by having the following configuration. That is,
The shoe sole according to claim 1, wherein the outsole is formed by injection molding so as to have a specific gravity of about 1.

According to a fourth aspect of the present invention, the following structure is provided. That is,
4. The shoe according to claim 1, wherein a corner portion constituted by a grounding surface and a side surface of each grounding block is formed to have a radius of about 0.1 mm or less. bottom.

  The invention described in claim 5 is characterized by having the following configuration. That is, a shoe provided with a shoe sole according to any one of claims 1 to 4 on a bottom surface.

The invention described in claim 6 is characterized by having the following configuration. That is,
A shoe sole having an upper, a midsole and an outsole,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
The outsole is formed of a polyurethane foam having a specific gravity of 0.9 to 1.2, and at least on the center of the forefoot region and the center of the buttock region, a quadrangle along each center or approximate to the rectangle A plurality of central grounding blocks having a polygonal grounding surface, and a polygonal grounding surface having a quadrangular shape or a shape similar to the quadrangular shape at a position separating the central grounding block from a longitudinal groove having a predetermined width. Provide multiple left and right grounding blocks,
The center grounding block and the left and right grounding blocks provided in the forefoot area are alternately arranged so as to be displaced in the front-rear direction, and the lateral grooves defining the front-rear direction of each grounding block are crank-shaped together with the vertical grooves. A groove that is bent
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that.

The invention according to claim 7 is characterized by having the following configuration. That is,
A shoe sole having an upper, a midsole and an outsole,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
The outsole is formed of a non-foaming material such as non-foamed rubber, non-foamed thermoplastic urethane, or non-foamed polyvinyl chloride, and at least on the center of the forefoot sole region and the center of the heel region. A plurality of central grounding blocks having a polygonal grounding surface with a quadrangle or a shape approximating the quadrangle, and a shape approximating the quadrangle or the quadrangle at a position separated from the central grounding block by a vertical groove having a predetermined width. A plurality of left and right grounding blocks having a polygonal grounding surface are provided,
The center grounding block and the left and right grounding blocks provided in the forefoot area are alternately arranged so as to be displaced in the front-rear direction, and the lateral grooves defining the front-rear direction of each grounding block are crank-shaped together with the vertical grooves. A groove that is bent
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that.

  The shoe sole according to the present invention and the shoe having the shoe sole are on a stainless steel floor surface coated with oil in the slip resistance measurement described in the safety shoe technical guideline which is the technical guideline of the Industrial Safety Institute. Also, it has an effect that it can exhibit extremely high slip resistance with a dynamic friction coefficient of about 0.3 or more than 0.3.

FIG. 1 is a diagram showing a shoe bottom of a shoe sole 100 according to the present invention. The shoe sole 100 is formed by injection (injection molding) using polyurethane foam (PU). The shoe sole 100 in the present embodiment has an outsole (sole bottom portion) 40 and a midsole (shoe sole intermediate portion) 41 as shown in FIGS. When the midsole 41 is formed by injection molding, the outsole 40 and the upper part 42 are joined by the midsole 41 to form the shoe 101.
The outsole 40 is formed to a thickness of about 2 to 3 mm as a whole, and a plurality of ground blocks (1 to 30) are formed on the bottom surface as shown in FIG.

The outsole 40 is divided into a forefoot region S2 which is the front part of the arch region S1, and a buttock region S3 behind the arch region S1, and is mainly provided in the forefoot region S2 and the buttock region S3 when walking. The grounding block is in contact with the floor.
In the forefoot region S2, grounding blocks indicated by reference numerals 1 to 20 are provided except for the toe portion. A plurality of ridges 43 having a semicircular cross section are provided at the tip portion so as to form a direction orthogonal to the center line CL1. The center line CL1 is a virtual line that connects from the vicinity of the center behind the front sole region S2 to the vicinity of the center of the front foot region S2.
Grounding blocks 1 to 20 described below are provided in the forefoot region S2 excluding the tip portion. The grounding block has a rectangular grounding surface that is long in the front-rear direction, except for the grounding blocks 14 to 20 provided near the left and right sides of the forefoot sole region S2 and the grounding block 5 at the rear end of the forefoot sole region S2. The grounding blocks 14 to 18 and the grounding block 5 at the rear end of the front sole region S2 are blocks that are in contact with the outer edge portion of the front sole region S2, and therefore the shape thereof is different from the rectangular shape. The grounding blocks 19 and 20 have a shape having a narrow grounding surface that is long in the front-rear direction.

Next, the shape and arrangement of the grounding block, which is one of the features of the present invention, will be described.
First, grounding blocks (central grounding blocks) 1 to 4 having a rectangular grounding surface that is long in the front-rear direction are arranged at substantially equal intervals on the center line CL1 of the forefoot sole region S2. Between each of the blocks, a horizontal groove having a width that is half or slightly narrower than the horizontal width of each of the ground blocks 1 to 4 is provided, and the groove defines each of the ground blocks 1 to 5.
Note that the bottom portion of the groove has a cross section close to a curved surface. In other words, the corners of the tops of the corresponding molds that are convex are not right angles but curved surfaces, and have a semicircular shape or a cross-sectional shape that is a flattened semicircle. This is because the flow of the resin during the injection molding is smoothed so as not to cause chipping due to remaining bubbles or the like at the corners (particularly the front edge portion) of the grounding block.
Secondly, ground blocks 6 to 9 and ground blocks 10 to 13 (left and right ground blocks) having the same ground plane shape as the ground blocks 1 to 4 are provided on the left and right of the ground blocks 1 to 5. Yes. Further, between the ground blocks 6 to 9 and between the ground blocks 10 to 13, lateral grooves having substantially the same width as the lateral grooves provided between the ground blocks 1 to 5 are provided. Between the blocks 6 to 9 and the ground blocks 10 to 13 are defined. Further, vertical grooves having substantially the same width as the horizontal grooves are provided between the grounding blocks 1 to 5 and the grounding blocks 6 to 9 and the grounding blocks 1 to 4 and the grounding blocks 10 to 13 in the center.
The ground blocks 6 to 9 and the ground blocks 10 to 13 provided on the left and right of the ground blocks 1 to 5 are not arranged in a horizontal line with respect to the central ground blocks 1 to 5, but are about half the length in the front-rear direction. It is arranged at a position displaced downward. As a result, the horizontal groove between the ground blocks 1 to 5 and the horizontal groove between the ground blocks 6 to 9 and the ground blocks 10 to 13 are not straight, but have a shape that is bent in a crank shape via the vertical groove. It has become.

Third, the grounding blocks 14 to 18 on the outer foot side of the forefoot sole region S2 have front and rear edges in a direction substantially perpendicular to the center line CL1, and side edges substantially parallel to the center line CL1 in the inner foot direction. Have. The side edges on the outer foot side of the grounding blocks 14 to 18 have a shape that matches the outer peripheral edge of the entire shoe sole.
Between each of the ground blocks 14 to 18, a lateral groove having substantially the same width as the lateral groove provided between the ground blocks 1 to 5 is provided.
The ground blocks 14 to 18 are disposed at positions displaced downward about half of the length in the front-rear direction with respect to the ground blocks 10 to 13. As a result, the horizontal groove between the ground blocks 10 to 13 and the horizontal groove between the ground blocks 14 to 18 are not in a straight line shape, but are bent into a crank shape via the vertical groove.

  Fourthly, the grounding blocks 19 and 20 on the inner foot side of the forefoot sole region S2 are configured as narrow ridges that are long in the front-rear direction. The ground block 19 is disposed substantially parallel to the arrangement direction of the ground blocks 6 to 9 through vertical grooves, and the ground block 20 is disposed parallel to the ground block 19 via vertical grooves. The outer edge of the grounding block 20 has a shape that matches the outer peripheral edge of the entire shoe sole. The width of the vertical groove partitioning each block is formed to be substantially the same as the width of the horizontal groove provided between the ground blocks 1 to 4.

The grounding surface of each grounding block provided in the forefoot sole region S2 forms a curved surface that gently curves in the front-rear direction and the left-right direction with the vicinity of the center grounding block 3 as a vertex. That is, each grounding block is independent by vertical grooves and horizontal grooves, but if there are no vertical grooves and horizontal grooves, it has a grounding surface that forms a continuous curved surface without extreme irregularities. .
Due to the shape of the grounding surface, even if the load moves in the front-rear direction and the left-right direction during walking, the grounding block with high slip resistance can effectively contact the floor surface and exhibit high slip resistance performance. It has become.

The forefoot region S2 is a portion formed by a nested mating die in which only the shape of the portion is formed by cutting. In addition, the mating die is formed with a concave portion for forming a grounding block on the surface of the plate-like material and a convex line for forming each groove with high accuracy, and then gently by a bending machine in the front and rear and left and right directions. It is bent to form a curved surface.
The mating mold used in the present invention is a straight groove corresponding to the vertical groove, in order to form the vertical groove provided in a straight line in the front-rear direction described above on the shoe bottom, and a lateral groove bent in a crank shape, It has a ridge that is not in a straight line corresponding to the lateral groove.
The arrangement of the protrusions of the mating mold (in other words, the arrangement of the concave portion of the shoe sole) does not cause local bending (particularly bending in the front-rear direction) during bending of the mold, and is curved uniformly as a whole. Thus, a gentle curved surface (grounding surface) can be formed. With the mold, the forefoot region S2 is not bent like a polygonal shape (polyhedron) by the partitioned grooves so that the surface portions of the respective grounding blocks form a continuous curved surface although they are separated from each other. It is what has become.

Next, the grounding block provided in the buttocks area S3 will be described. In the buttocks region S3, four ground blocks 21 to 24 are provided on the center line CL2, and ground blocks 25 to 27 and ground blocks 28 to 30 are provided on both sides of the ground blocks 21 to 24 via vertical grooves. The rear end portion is provided with a plurality of ridges 44 having a semicircular cross section in a direction orthogonal to the center line CL2.
Each of the grounding blocks 21 to 30 has a substantially rectangular grounding surface, and is defined by vertical grooves and horizontal grooves having substantially the same width as the vertical grooves and horizontal grooves that define the grounding blocks of the forefoot sole region S2. ing.
Unlike the above-described grounding block in the forefoot sole region S2, the grounding surfaces of the grounding blocks 21 to 30 provided in the buttocks region S3 are provided so as to form a plane that is not curved.

Each grounding block described above has the following features.
First, the angle of the periphery of the grounding surface of each grounding block (the angle formed by the grounding surface and the side surface) is almost a right angle, and is in the range of approximately 90 degrees or 93 degrees that is an obtuse angle from 90 degrees. It is desirable to set.
Second, the corners of the respective grounding blocks are ideally rounded, but are formed to have a radius of 0.1 mm or less due to processing restrictions. In addition, an injection port for injection molding is provided on the heel side so that the resin is supplied from the heel side toward the front, and the resin spreads at least at the corner of the front edge of the grounding block by this method. In addition, a lack of meat (meat missing) due to air accumulation or the like is less likely to occur.
Third, the surface of the grounding surface of each grounding block is formed as a flat surface with very few irregularities. In the present embodiment, the grounding block is formed by a mold formed by cutting aluminum with an end mill. The surface of the ground contact surface is formed by a mold that is formed so that the cut surface is not uneven as much as possible in the cutting of aluminum using the end mill.
Fourth, the height of each grounding block is 3 mm as the optimum height. The height is set in the range of 1 to 7 mm according to the shape and area of the ground contact surface, and does not cause extreme lateral deformation, and the ground contact surface and corners are effective with respect to the floor surface. The height is set so as to satisfy the contact condition. In addition, the height is set as an optimum height from the viewpoint of allowing the resin to flow smoothly during molding and to reach the corners in the recesses that form the grounding block.
Fifth, each grounding block has a front end edge that is at least orthogonal to or slightly inclined with respect to the center line, and has a relatively large rectangular shape or a shape approximate to a rectangular shape.

  Sixth, the hardness of the grounding block is 55 to 85 when measured in a temperature environment of 20 ° C. with a spring type C hardness tester (manufactured by Kobunshi Keiki Co., Ltd .: ASKER C type) according to JIS K7312. It is formed as follows.

When the shoe sole (outsole) according to the present invention is formed by injection molding (for example, RIM type), the bottom mold (bottom side mold), the side mold (left and right divided molds), and the upper portion 42 are attached. Alternatively, a mold made of a dummy mold that replaces it is temporarily tightened to make a larger volume than the planned volume (outsole molded body volume). Inject raw material). At that time, the raw material stays in the buttocks. After injection, the bottom of the mold is raised (8 mm), that is, the bottom mold is raised and compressed to a predetermined volume. At this time, the material flows from the buttocks to the foot (front sole region). Polyurethane material has poor wettability to the mold, and due to low pressure, it does not flow into the corners, causing a phenomenon that the corners of the block are chipped (chips, thinning), and the block corners are easily chipped. However, it is the gist of the invention that this problem is devised in the size and arrangement of the blocks so that the flow of the liquid mixture is controlled so that chipping (slicing) is difficult to occur.
In addition, in the case of injection molding, if the filling amount of the material is large, the pack rate increases and the reproducibility of the mold tends to improve, so in this embodiment, an angle as close to a right angle as possible is formed, The shoe soles according to the mold with reduced surface roughness are formed. In addition, by increasing the material filling amount, the outsole can be made harder, thereby preventing deformation such as falling of the grounding block, and high slip resistance due to the synergistic effect with the shape accuracy of the grounding block. It comes to show the sex.

  The above is the configuration provided for each grounding block. By providing the above configuration, the corners of each grounding block cut off the water and oil on the floor surface, and the water and oil are removed from the grounding surface of each grounding block to remove the floor surface. It is possible to demonstrate high slip resistance between the ground surface and the floor surface by keeping water and oil from entering between the ground surface and the floor surface. .

2a shows a side cross section of the shoe sole portion of the shoe sole 100 provided on the shoe 101, and FIG. 2b shows a side view of the shoe sole portion. The relationship between the forefoot sole region S2 and the buttocks region S3 will be described with reference to FIG. 2b. As described above, the grounding surface of the grounding block in the buttocks region S3 is formed to be the same plane. The grounding surface of the grounding block in the forefoot region S2 is formed to have the same curved surface. And it is formed so that the vicinity of the center of the front sole region S2 is higher (height h) than the height of the ground contact surface of the ground contact block in the buttocks region S3. With this configuration, the grounding block near the center of the front sole region S2 is always in contact with the floor surface during walking.
The curvature radius of the curved surface of the front sole region S2 is about 278 mm in the front-rear direction and about 647 mm in the left-right direction.

  Further, the outsole 40 forming the grounding block is engaged with the upper portion 42 through the midsole 41. The midsole 41 is a part for connecting the outsole 40 and the upper part 42, filling the upper surface of the outsole 40, and maintaining the shape of the outsole 40 and exhibiting cushioning properties as a shoe. .

Next, some experimental results will be described in order to explain matters that are elements that exhibit slip resistance.
FIG. 3 shows an enlarged photograph of a corner portion of the grounding block and an enlarged photograph of the grounding surface. FIG. 3a1 is an enlarged photograph of a corner portion of a normal grounding block that satisfies the above-described conditions, and FIG. 3a2 is an enlarged photograph of the grounding surface of the grounding block. The dynamic friction coefficient of the shoe having the shoe sole shown in FIG. 1 having the grounding block in this state was 0.44.
On the other hand, FIG. 3b1 is an enlarged photograph of the corner portion of the front edge of the grounding block whose corners are cut with sandpaper. In FIG. 3b1, the dynamic friction coefficient in this state is 0.29, which is 34% lower than that in the normal state.
FIG. 3b2 is an enlarged photograph of the ground contact surface of the ground contact block whose surface has been roughed with sandpaper. The dynamic friction coefficient of the shoe having the shoe sole shown in FIG. 1 having the grounding block in this state was 0.26, which was 41% lower than that in the normal state.
From this result, it can be said that it is desirable that the corner of the grounding block that contacts the floor surface is not rounded, and that the contact surface is not a rough surface but a smooth surface with few irregularities.

FIG. 4 shows the effect of the arrangement of the grounding block on the surface of the outsole 40 on the slip resistance.
a1 represents the pattern of the grounding block which the shoe sole 100 based on this Embodiment has. The dynamic friction coefficient in the case of a1 is 0.46, and it can be seen that the outstanding slip resistance performance is exhibited. a2 to a6 and a10 are obtained by changing the arrangement and the like of the grounding block in the forefoot sole region S2. The dynamic friction coefficients for each pattern are 0.35, 0.34, 0.36, 0.37, 0.38, and 0.44. Both have high slip resistance, but when the grounding block is provided on or near the center line CL1, the slip resistance is high, and when there is no ground block near the center line CL1, the slip resistance is low. I understand that Therefore, in order to exhibit remarkable slip resistance, it is desirable to provide a grounding block on the center line CL1 or in the vicinity of the center line CL1.

  Further, a7, a8, and a9 in FIG. 4 represent examples in which the arrangement of the grounding blocks in the buttocks area S3 is changed without changing the arrangement of the grounding blocks in the forefoot sole area S2. The dynamic friction coefficients of each pattern were 0.39, 0.37, and 0.39. From the results, regarding the arrangement of the grounding block in the buttock area S3, the case of a1 exhibits remarkable slip resistance, and next, three grounding blocks with the corners aligned on the front edge of the buttock area S3 are provided. It was found that the anti-slip performance was relatively good when provided.

  Each of the above-mentioned dynamic friction coefficients was measured in accordance with the slip resistance specified in the “Technical Safety Institute Technical Guidelines for Safety Shoe” (hereinafter simply referred to as “Technical Guidelines”) issued by the Industrial Safety Research Institute in March 1991. The test was conducted according to the method and conditions of the sex test. Note that the dynamic friction coefficient is measured by applying oil to the stainless steel floor, applying a downward load to the shoes on the floor, and moving the floor while applying the load. The dynamic friction coefficient is calculated based on the generated resistance force.

5, 6, and 7 show a shoe (a 1, 101) using a shoe sole according to the present invention and two other types of shoes (b 1, b) having a polyurethane sole. It shows various comparisons of c1).
The upper part of FIG. 5 shows a photograph of the bottom surface of each of the shoes (a1, b1, c1) serving as the comparison reference, and the second part is an enlarged view of the corner of the grounding block corresponding to each shoe (a1, b1, c1). Photographs (a2, b2, c2), the third row is a graph (a3, b3, c3) showing an example of the measurement result of the dynamic friction coefficient corresponding to each shoe (a1, b1, c1). It is the table | surface (a4, b4, c4) showing the measurement result of the dynamic friction coefficient of shoes (a1, b1, c1). Further, the intermediate ternary average shown in each table (a4, b4, c4) is an average value of three intermediate values excluding the maximum value and the minimum value among five measurements. According to the measurement result, as a result of measuring the dynamic friction coefficient in accordance with the technical guideline, the dynamic friction coefficient of the shoe a1 according to the present invention is 0.40, and the dynamic friction coefficients of the other shoes b1 and c1 are 0.21, respectively. It was 0.20.

FIG. 6 is a photograph showing a ground contact state when a person actually wears each of the shoes a1, b1, and c1. The photograph was taken using a device called a pidoscope that brightly visually recognizes only a portion grounded on a glass plate.
FIG. 7 is an explanatory diagram showing the area of the part actually in contact for each grounding block based on the imaging result by the pidoscope shown in FIG.

As described above, the shoe sole according to the present embodiment has a shape in which the cross section of the bottom portion of the groove provided between the grounding blocks is curved. The shoe sole centering on the shape will be described with reference to FIG.
FIG. 8A is a bottom view of the outsole 40 with the front foot sole region S2 as a center. FIG. 8B is a cross-section (XX ′ line cross-section) along the center line CL1 corresponding to FIG. 8A. Is an explanatory diagram of 50, 51, 52, 53.
Symbols A, B, C, D, E, F, and H that are commonly used in FIGS. 8a and 8b are symbols representing the dimension values of the portions indicated by arrows. A is a bridge | bridging part thickness, and a dimension range is 1-3 mm. B and J are bridge part widths, and the dimension range is 4 to 7 mm. C is the height of the bridge portion, and the dimension range is 2 to 6 mm (where C> A). D is the vertical width of the grounding block, and the size range is 15 to 30 mm. E is the grounding block thickness, and the size range is 1.5 to 8 mm. F is the width of the grounding block, and the size range is 5 to 15 mm. H is the vertical displacement amount of the grounding block, and the dimension range is 0 to 30 mm. Each of the above dimension values is one of the conditions for the shoe sole according to the present invention to exhibit a predetermined slip resistance.

  The outsole 40 constituting the shoe sole 100 is formed by the RIM method described above or an injection molding method in which a molten resin is injected through a gate. In any case, the molten resin is directed from the heel side to the toe direction in the mold. Adopting a flow method. In shoes exhibiting slip resistance, the accuracy of the corner of the front edge of the grounding block is important, and it is important that the corner has a squareness without roundness. As one condition for maintaining the accuracy of the corner, each dimension value is adopted, and in particular, the dimension condition in the vertical direction (direction connecting the heel and the tip) is important. In addition to the shape of the mold defined by the dimension value, slip resistance is obtained by a method in which the molten resin flows from the heel side toward the toe.

The dimensions A, B, C, D, E, F, H, and J of the outsole 40 centering on the shape of the grounding block are, in other words, the molds for forming a shoe sole exhibiting slip resistance. The shape is defined, and the corresponding mold dimensions are A ′, B ′, C ′, D ′, E ′, F ′, H ′, and J ′ as required. In the following description, F ′, H ′, and J ′ of the dimensions of the mold will not be described.
The general injection molding of plastic has a molding pressure of several tens to several hundreds of MPa, whereas the outsole 40 constituting the shoe sole according to the present invention has a molding pressure of about 2 kg / cm ² (about 196 kPa), and the viscosity of the molten resin is relatively high.

  FIG. 9a, FIG. 9b, and FIG. 9c are explanatory views showing the state of the molten resin that moves in the mold by the molding pressure, and the spatial shape formed by the upper mold (dummy mold) and the lower mold (bottom mold) This is to explain the difference in the flow of the molding resin due to the difference. Each figure shows a state in which the molten resin R flows from the right (heel side) to the left (toe side) through the space surrounded by the upper mold and the lower mold.

FIG. 9a shows the shape in the longitudinal direction inside the mold formed by the lower mold 60 formed with a large number of recesses 66 forming the outer shape of each grounding block and the upper mold 61 on the flat inner surface, and the molten resin flowing in the mold. Represents the state.
A ′ in FIG. 9 a is the distance (the thickness of the bridge portion) between the upper end 65 of the wall 62 forming the recess 66 of the lower mold 60 and the inner surface of the upper mold 61 at a position facing the upper end 65. A ′ is 1 to 3 mm. Further, C ′ in FIG. 9 a is the amount of protrusion (bridge height) from the inner surface of the upper mold 51 to the concave portion 66 side of the lower mold 60 at a portion not facing the upper end 65 of the wall 62. In the illustrated example, C ′ = 0 mm.
In the case of the above conditions, the molten resin R that has flowed in from the right side flows mainly to the toe side along the flat inner surface of the upper mold 61. At this time, since the molten resin R does not have an injection pressure sufficient to reach every corner in the recess of the lower mold 60, the resin does not rotate to the corners 63 and 64 in the recess. As a result, the corner portion of the grounding block is chipped or rounded. If the corner portion of the grounding block is chipped or rounded due to such an insufficient molding state, sufficient slip resistance performance as a shoe sole cannot be exhibited.

FIG. 9b shows the inside of the mold by the lower mold 70 and the upper mold 71 provided with a large number of recesses 76 for forming the grounding block, and the state of the molten resin flowing in the mold.
A ′ in FIG. 9 b represents the distance (bridge portion) between the upper end 73 of the wall 72 forming the recess 76 of the lower mold 70 and the inner surface of the recess 74 of the upper mold 71 at a portion facing the upper end 73. Further, C ′ is the maximum position of the inner surface of the depression 74 of the upper mold 71 that is one end of the A ′ and the distance from the highest position to the inner surface 75 of the upper mold 71 at the site where the wall 72 is not provided.
In FIG. 9 b, the upper die 71 is provided with a recess 74 corresponding to the upper end 73 of the wall 72, and the position of the upper end 73 is substantially the same height (A′≈C ′) as the flat surface (75) of the upper die 71. The state provided so that it becomes.
The width of the wall 72 is B ′, and the upper end 73 of the wall 72 is formed as an arcuate curved surface. Similarly, the inner surface of the recess 74 of the upper mold 71 facing the arcuate curved surface is also formed in an arcuate curved surface, and the distance between the molds 70 and 71 in the arcuate portion is substantially uniform.

  In the example of the lower mold 70 and the upper mold 71 shown in FIG. 9b, the molten resin R flowing from the right side passes between the upper end 73 of the wall 72 of the lower mold 70 and the depression 74 of the upper mold 71. It is guided toward the bottom surface side of the recess 76 of the lower mold 70. This makes it easier for the resin to turn to the corner in the recess 76, and the corner of the grounding block is less likely to be chipped or rounded. In this way, by satisfying at least the condition of A ′ = C ′, it is possible to reduce the frequency of occurrence of chipping at the corners of the grounding block, and to form a shoe sole exhibiting slip resistance. become.

FIG. 9 c shows the state of the molten resin flowing inside the mold formed by the lower mold 80 provided with a large number of recesses 86 for forming the grounding block and the upper mold 81.
A ′ in FIG. 9c is the distance (the thickness of the bridge portion) at the highest portion between the upper end 83 of the wall 82 forming the recess 86 of the lower die 80 and the inner surface of the depression 84 of the upper die 81 at the portion facing the upper end 83. Represents. C ′ is the maximum position of the inner surface of the depression 84 of the upper mold 81 that is one end of the A ′, and the distance from the highest position to the inner surface 85 of the upper mold 81 at the site where the wall 82 is not provided. In other words, it is the depth of the recess 84 with reference to the inner surface 85 of the upper mold 81.
When A ′ and C ′ are defined as described above, the relationship between the lower mold 80 and the upper mold 81 shown in FIG. 9C is a condition of C ′> A ′. In other words, the width of the recess 84 with the upper end formed as an arcuate curved surface 83 is a state where a wall 82 of B ′ enters.
Further, the depression 84 of the upper mold 81 facing the arcuate upper end 83 is formed as an arcuate curved surface like the upper end 83, and the distance between the upper end 83 and the inner surface portion of the depression 84 is substantially uniform. ing. The thickness E of the grounding block (thickness of the bottom surface of the recess) is 1.5 to 8 mm.

When the condition of C ′> A ′ shown in FIG. 9C is set (the state in which the upper end 83 of the wall 82 of the lower mold 80 serving as the boundary of the grounding block enters the recess 84 of the upper mold 81), the molten resin R is first To the bottom surface of the concave portion 86 of the lower mold 80, filling the heel side corner portion in the concave portion 86, following the bottom surface of the concave portion 86, and then filling the toe side corner portion in the concave portion 86 in the same manner Fill the next recess. As described above, although the molding pressure is relatively low, the molten resin R is sufficiently spread particularly at the corner of the tip portion of the grounding block, thereby preventing the chipping and the rounded corner.
As described above, the shape of the lower die 80 and the upper die 81 is made such that a curved (arched) communication portion (bridge portion) is formed between the grounding blocks, so that the resin is formed at the corner portion. Even if the molding pressure is relatively low, the tip edge of the grounding block can be prevented from being chipped or rounded. The resin is flowing from the heel side toward the toe side because the resin is pressed toward the front when the resin is supplied to the concave portion forming the grounding block. This is because the corners on the front end side are more easily filled with resin, and chipping is less likely to occur. In order to demonstrate slip resistance performance, it is important that the corner of the tip edge of the grounding block is not chipped or rounded, so the present invention adopts a method of supplying resin from the heel side together with the shape of the mold. Yes.
Further, the arch-shaped communication portion has a structure in which adjacent grounding blocks are connected to each other at a portion directly above the outer periphery of each grounding block. And a part of load which acted on the midsole at the time of a walk is disperse | distributed to the outer peripheral part of each grounding block via the said arch-shaped communication part. That is, the load at the time of the walk which acted on the site | part in which each grounding block is not provided is transmitted to each grounding block outer peripheral part via an arch-shaped communication part, and the load of an outer peripheral part is increased rather than the center part of a grounding block. Has an effect. As described above, the outer peripheral portion of the grounding surface of each grounding block is formed to have a right angle, and the shape of the outer peripheral portion of the grounding surface of the grounding block can provide high slip resistance. . Further, by increasing the load amount of the corner portion of the outer peripheral portion of the ground contact surface by the action of the arch-shaped communication portion, a higher slip resistance performance is obtained by a synergistic effect with the structure in which the corners are perpendicular.

The shoe sole according to the present invention described above uses an outsole formed by molding a foamable material such as foamed polyurethane. Thereafter, the inventor conducted research on materials other than those described above as materials for the outsole and the midsole, and there was a material that was confirmed to be slip resistant. The material will be described with reference to FIG. FIG. 10 shows material names of the outsole and the midsole that can be used as the shoe sole 100 according to the present invention, and the hardness and specific gravity of each material.
The details are as shown in FIG. 10, but as the outsole, foamed polyurethane, non-foamed rubber, non-foamed thermoplastic urethane, or non-foamed polyvinyl chloride can be used. In addition, as the midsole, foamed polyurethane and foamed rubber can be used. The numerical values displayed as hardness A and hardness C in FIG. 10 are values measured by a spring type A hardness meter (hardness A) and a spring type C hardness meter (hardness C) described later. In addition, since selection of the hardness meter is distinguished by soft foaming property and relatively hard non-foaming property, hardness is usually measured by one of the hardness meters. In the table of FIG. 10, the numerical value without () is a measurement result by a normally used hardness meter, and the numerical value described in () is a measurement value by a hardness meter that is not normally used as a reference value. . The specific gravity of each material is also as described in the table.
In Table 10, the polyurethane foam used for the outsole is described as hardness C70 to 85 and 90. As a result of testing with hardness C90 alone in addition to hardness C70 to 85, good slip resistance was obtained, and the results are described.

  The hardness A and hardness C described in the table shown as FIG. 10 will be described. Hardness A and hardness C are numerical values measured by a spring-type hardness meter (hereinafter referred to as “hardness meter”) called a Durometer. The hardness meter will be briefly described with reference to FIG. The hardness A is a numerical value measured with a spring type A hardness meter described below, and the hardness C is a numerical value measured with a spring type C hardness meter.

M1, M2, and M3 shown in the figure represent a stationary state and an operating state of the same hardness meter 200, respectively. The hardness meter 200 has a flat pressure surface 201 having a specified surface area, and a push needle 203 pressed by a spring 202 protrudes from the center of the pressure surface 201 and is proportional to the retraction amount of the push needle. By operating the pointer 204, a numerical value in the range of 0 to 100 is expressed as hardness.
The factors that determine the properties of the hardness meter are mainly the tip shape of the push needle 203, the setting of the spring 202 that pressurizes the push needle (the spring constant and the initial load when the push needle starts to retract), the push needle Stroke (distance until the tip reaches the same surface as the pressure surface 201).

In the hardness meter 200, the pointer 204 indicates “0” in the state of M1 (the state before the start of measurement). In this state, an initial load is applied to the push needle 203 due to the elasticity of the spring 202. For example, in the case of a hardness meter conforming to JISK6301 shown in FIG. 12, the initial load is 539 mN.
Further, the state in which the hardness meter 200 is pressed against a hard object and the push needle 203 is pushed up to the same surface as the pressing surface 201 (M3 in FIG. 11) is a state in which the pointer 204 indicates “100” as the hardness 100. For example, in the case of the hardness meter in conformity with JISK6301 shown in FIG. 12, the load of the push needle 203 when the hardness is 100 is 8379 mN.
M2 in FIG. 11 represents the actual measurement state. When the hardness meter 200 is pressed until the pressing surface 201 is pressed against the surface of the test body 205, the push needle 203 rises as the test body 205 is deformed. The pointer 204 points to a predetermined numerical value in proportion to the load acting on the push needle 203 at this time. The numerical value shown at this time is the hardness.

  Further, M5 in FIG. 11 is a diagram showing the shape of the push needle of the spring type A-type hardness meter, and is the same shape as the old JIS standard and the new JIS standard conforming to the current ISO standard. M6 in FIG. 11 is a diagram showing the shape of the push needle of the spring type C-type hardness meter.

FIG. 12 shows the main elements of the spring type A hardness tester according to the old JIS standard described as the hardness in the present specification, and the main elements of the spring type A hardness tester according to JISK6253 which is the same as ISO7619 which is the current standard. Is a comparison table. The two standards are the above-described setting of the spring that pressurizes the push needle (spring constant and load when the push needle starts to retract), and the stroke of the push needle (the distance until the tip is flush with the pressurization surface) ) Is slightly different.
FIG. 13 is a table showing the main elements of a spring-type C-type hardness meter (conforming to JIS / K7312) used to indicate the hardness of a shoe sole formed of a foam material such as urethane foam or EVA in this specification. It is. As can be seen by comparing the contents of JIS K6301 in FIG. 13 and FIG. 12, the difference between the two is the shape of the tip of the push needle.

  The present invention can be used for the formation of a shoe sole having remarkable slip resistance even on a stainless steel plate or the like having an oil film, a shoe using the shoe sole, a method for forming a shoe sole, and the like.

It is a figure showing the surface shape of the shoe sole which concerns on this invention. a figure is a sectional view of the principal part of the shoe according to the present invention, b figure is a side view of the principal part, c figure is a sectional view taken along line AA 'shown in the principal part side view, and d figure is a side view of the principal part. It is sectional drawing of the BB 'line shown in FIG. It is the corner | angular part enlarged photograph and surface enlarged photograph of the grounding block provided in the shoe sole which concerns on this invention, the corner | angular part enlarged photograph and surface enlarged photograph of the grounding block at the time of experiment. a1 is an enlarged photograph of a corner portion of a normal grounding block, and a2 is an enlarged photograph of the grounding surface of the grounding block. Further, b1 is an enlarged photograph of the corner portion of the front edge of the grounding block whose corner is cut with sandpaper, and b2 is an enlarged photograph of the grounding surface of the grounding block whose surface is sharply ground with sandpaper. It is a photograph showing arrangement | positioning of the ground-contact block of the shoe sole which measured the dynamic friction coefficient. FIG. A1 shows the pattern of the grounding block of the shoe sole according to the present embodiment, and FIGS. A2 to a6 and FIG. A10 are patterns obtained by changing the arrangement of the grounding block in the forefoot sole region. a7, FIG. a8, and FIG. a9 are patterns obtained by changing the arrangement of the grounding blocks in the buttocks region. It is an explanatory photograph and experimental result for demonstrating the comparison content of the shoes based on this invention, and other shoes. FIG. A1 is a shoe according to the present invention, and FIGS. A1, b1, and c1 are bottom photographs of other shoes. FIGS. A2, b2, and c2 are enlarged photographs of the corners of the grounding block corresponding to each shoe, and FIGS. A3, b3, and c3 are the measurement results of the dynamic friction coefficient corresponding to each shoe, Table a4, Tables b4 and c4 show the results of formulating the dynamic friction coefficient of each shoe. It is the photography photographed with the pidoscope of the shoes concerning this invention, and other shoes. FIG. A relates to a shoe sole according to the present embodiment, and FIGS. B and c relate to other shoes. It is explanatory drawing which represented the area of the grounding part made into the figure based on the imaging | photography result by the pidoscope of FIG. 6, and made into the figure. FIG. A relates to a shoe sole according to the present embodiment, and FIGS. B and c relate to other shoes. FIG. 8A is an explanatory view of an outsole according to the present invention, FIG. 8A is a bottom view centering on a forefoot sole region of the outsole, and FIG. 8B is a partial cross-sectional view taken along a center line CL1 shown in FIG. It is explanatory drawing showing the mode of the movement of the molten resin according to the shape of a metal mold | die. It is the list showing the material which can be used for the shoe sole which concerns on this invention. It is explanatory drawing of a hardness meter. It is explanatory drawing of a spring type A type hardness tester (ISO * 7619 type hardness tester). It is explanatory drawing of a spring type C type hardness tester (JIS * K7312 type hardness tester).

Explanation of symbols

100 Shoe sole 101 Shoe 1-20 Grounding block 40 Outsole (sole bottom)
41 Midsole (middle sole)
42 upper part 43 ridge 44 ridge S1 arch area S2 forefoot area S3 buttocks area

Claims (7)

A shoe sole having an outsole formed by molding a foamable material such as a midsole and polyurethane foam,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
In the outsole, at least on the center of the forefoot region and the center of the buttock region, a plurality of central grounding blocks having a polygonal grounding surface of a quadrangle or a shape similar to the quadrangle along each center, A plurality of left and right grounding blocks having a quadrangular or polygonal grounding surface in a shape approximating the quadrangle is provided at a position separating the central grounding block and a vertical groove having a predetermined width,
The angle formed by the side surface of each grounding block and the grounding surface is substantially a right angle,
The center grounding block and the left and right grounding blocks provided in the forefoot sole region are provided alternately so as to be displaced by about half of the length in the front-rear direction, and the lateral grooves that define the front-rear direction of each grounding block are: A groove that is bent in a crank shape is formed with the longitudinal groove,
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that.   The shoe sole according to claim 1, wherein the outsole has a hardness of 55 to 85 as measured by a spring type C-type hardness meter in accordance with JIS K7312.   The shoe sole according to claim 1, wherein the outsole is formed by injection molding so as to have a specific gravity of about 1.   4. The shoe according to claim 1, wherein a corner portion constituted by a grounding surface and a side surface of each grounding block is formed to have a radius of about 0.1 mm or less. bottom.   The shoe which provided the sole in any one of the said Claims 1 thru | or 4 in the bottom face. A shoe sole having an upper, a midsole and an outsole,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
The outsole is formed of a polyurethane foam having a specific gravity of 0.9 to 1.2, and at least on the center of the forefoot region and the center of the buttock region, a quadrangle along each center or approximate to the rectangle A plurality of central grounding blocks having a polygonal grounding surface, and a polygonal grounding surface having a quadrangular shape or a shape similar to the quadrangular shape at a position separating the central grounding block from a longitudinal groove having a predetermined width. Provide multiple left and right grounding blocks,
The center grounding block and the left and right grounding blocks provided in the forefoot area are alternately arranged so as to be displaced in the front-rear direction, and the lateral grooves defining the front-rear direction of each grounding block are crank-shaped together with the vertical grooves. A groove that is bent
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that. A shoe sole having an upper, a midsole and an outsole,
The midsole is made of a foamable material such as the foamable rubber or polyurethane foam,
The outsole is formed of a non-foaming material such as non-foamed rubber, non-foamed thermoplastic urethane, or non-foamed polyvinyl chloride, and at least on the center of the forefoot sole region and the center of the heel region. A plurality of central grounding blocks having a polygonal grounding surface with a quadrangle or a shape approximating the quadrangle, and a shape approximating the quadrangle or the quadrangle at a position separated from the central grounding block by a vertical groove having a predetermined width. A plurality of left and right grounding blocks having a polygonal grounding surface are provided,
The center grounding block and the left and right grounding blocks provided in the forefoot area are alternately arranged so as to be displaced in the front-rear direction, and the lateral grooves defining the front-rear direction of each grounding block are crank-shaped together with the vertical grooves. A groove that is bent
The bridge portion formed between the grounding blocks has an arched cross-sectional shape in which the upper side and the lower side are curved in an arc shape, and protrudes toward the midsole side from the boundary surface between the grounding block and the midsole. Shoe sole characterized by that.

Images