HK1095249B - Insole assembly for increasing weight of footwear & heavy footwear having weight-increasing midsole/outsole - Google Patents

Description

Insole assembly for increasing weight of footwear and heavy footwear having a weight-increasing midsole/outsole

Technical Field

The present invention relates to heavy articles of footwear having increased weight. More particularly, the present invention relates to an insole assembly made of an extruded resin for potentially increasing the weight of an article of footwear employing the insole assembly. Further, the present invention relates to a heavy footwear including an outsole and/or a midsole made of compressed resin having a high specific gravity to enhance an exercise effect.

Background

Various techniques have been proposed which are capable of increasing the weight of an article of footwear in the event that it is necessary to enhance the wearer's exercise effect while reducing the weight at ordinary times.

An example of this technique is disclosed in korean registered utility model serial No. 285242 entitled "Sports short for execute". According to this document, heavy metal pieces are removably inserted into an outsole or bottom sole (bottomsole) that is the outer bottom of an article of footwear to enhance the wearer's exercise effect.

Another example is disclosed in korean registered utility model serial No. 298008, entitled "WeightAdiustable Footwear Liner", which was filed by the inventors of the present application. This document proposes to insert a metal element in an insole or insert placed in the body of the footwear, in order to increase the weight of the footwear and thus to enhance the wearer's exercise effect.

According to the conventional art, a high specific gravity material (e.g., metal) inserted into the outsole or the insole for increasing the weight of the shoe reduces the absorption capacity of the shoe for load impact (load impact) applied to a wearer, and thus an additional shock-absorbing means is required.

The prior art has another drawback of increasing manufacturing time and cost due to the additional molds and machining and assembly processes required to provide a detachable structure for the insert which adds weight.

An insert made of metal is inconvenient for a person wearing the above-mentioned article of footwear or shoe, because he/she must take off the shoe or remove the metal piece from the shoe while passing through the airport scanner.

Furthermore, when washing in a washing machine, these shoes may be soiled by rust of the metal member.

In addition, if the shoe is used for a predetermined period of time, the rubber outsole is worn away, exposing the metal pieces, which in turn strike the ground, producing an unpleasant sound.

Therefore, there is a need for new methods (devices) that overcome the aforementioned problems while adjusting the weight of the shoe.

Disclosure of Invention

It is therefore an object of the present invention to provide an insole assembly that increases the weight of footwear when attached thereto.

It is another object of the present invention to provide an insole molded from a heavy extruded resin to impart a desired degree of load bearing cushioning capacity to the human body of footwear without the need for additional cushioning means.

It is a further object of the present invention to insert weight elements into the midsole and/or outsole to increase the weight of the article of footwear.

It is yet another object of the present invention to manufacture the midsole and/or outsole from a high specific gravity extruded resin to increase the weight of the footwear.

According to an aspect of the present invention for achieving the above objects, there is provided an insole assembly for increasing the weight of footwear, comprising: a lower insole made of an extruded resin having a high specific gravity, and an upper insole positioned above the lower insole.

Preferably, the lower insole is made of a compression molded resin.

It is also preferred that the molding resin has a specific gravity of at least 2.

The insole assembly may further comprise a cushioning member attached to the rear end of the upper insole.

According to another aspect of the invention for achieving the above objects, there is provided an article of footwear having a large weight, including: a body for receiving a foot; an outsole attached to the main body for supporting the foot, at least a portion of the outsole being made of an extruded resin having a high specific gravity; and an insole positioned over the outsole within the body.

It is preferable that the entire outsole is made of a high specific gravity compressed resin.

It is also preferable to insert a high specific gravity compression resin into the outsole.

The heavy weight footwear may further include a midsole interposed between the outsole and the body, at least a portion of the midsole being made of a high specific gravity compressed resin.

It is preferable that the whole of the midsole is made of a high specific gravity extrusion resin.

It is also preferable to insert a high specific gravity extrusion resin into the midsole.

According to still another aspect of the present invention for achieving the above objects, there is provided an article of footwear having a large weight, including: a body for receiving a foot; a midsole connected to the main body for supporting the foot, at least a portion of the midsole being made of an extruded resin having a high specific gravity; an outsole attached to a lower surface of the midsole; and an insole positioned above the midsole within the body.

It is preferable that the whole of the midsole is made of a high specific gravity extrusion resin.

It is also preferable to insert a high specific gravity extrusion resin into the midsole.

Drawings

FIG. 1 is an exploded perspective view of an insole assembly for increasing the weight of an article of footwear according to a first embodiment of the present invention;

FIG. 2 is an exploded perspective view of an insole assembly for increasing the weight of an article of footwear according to a second embodiment of the present invention;

FIG. 3 is a cross-sectional view of the lower insole shown in FIG. 2;

FIG. 4 is a top view of FIG. 3;

FIG. 5 is a bottom view of FIG. 3;

FIG. 6 is a cross-sectional view of the upper insole shown in FIG. 2;

FIG. 7 is a top view of FIG. 6;

FIG. 8 is a bottom view of FIG. 6;

FIG. 9 is a side elevational view of an article of footwear having the insole assembly of the present invention placed therein;

FIG. 10 is a side view of a heavy article of footwear for enhancing the effectiveness of an exercise according to a third embodiment of the present invention;

FIG. 11 is an exploded perspective view of a heavy article of footwear according to a third embodiment of the present invention;

FIG. 12 is an exploded perspective view of a heavy article of footwear according to a fourth embodiment of the present invention; and

fig. 13 is an exploded perspective view of a heavy article of footwear according to a fifth embodiment of the invention.

Detailed Description

The foregoing and other features and advantages of the invention will now be described in detail with reference to the accompanying drawings.

Figure 1 is an exploded perspective view of an insole assembly for increasing the weight of an article of footwear (e.g., a shoe) in accordance with a first embodiment of the present invention.

Referring to fig. 1, the insole assembly 100 of the present invention comprises: a heavy insole (weight insole) or a lower insole 110 made of an extruded resin having a high specific gravity to increase the weight of the shoe, a shock absorbing member 130 attached at the heel of the lower insole 110, and an upper insole 140 positioned above the lower insole 110.

The heavy or lower insole 110 embodying the main idea of the present invention is manufactured by molding a desired resin to a specific gravity of at least about 2. The resin contains nitrile rubber, butadiene rubber, barium sulfate (BaSO) as high specific gravity filler₄) Lead oxide (Pb)₃O₄) ZnO, S, stearic acid and a vulcanization accelerator. Alternatively, the resin may be compressed, then cut, and then re-processed into the shape of the insole to manufacture the insole.

The lower insole 110 of high specific gravity may be manufactured separately from the shoe so that it can be detachably attached to the shoe or integrally attached to the shoe by an adhesive or the like, if necessary.

The shock absorbing member 130 is attached to the heel or rear end 110b of the lower insole 110 and is made of an elastic material capable of absorbing impact load applied to a wearer during movement thereof. In addition, the rear corners (rear horns) of the shock absorbing members are rounded to more effectively absorb shock during a step and ensure comfortable walking.

The upper insole 140 includes: a support portion 142 placed on the lower insole 110, a resilient portion 144 positioned on the support portion 142, and a sole contacting portion 146 positioned on the resilient portion 144 to contact the sole of the wearer's foot.

The support 142 is made of, for example, Ethylene Vinyl Acetate (EVA) of a predetermined thickness to prevent twisting (e.g., abduction or adduction) of the wearer's foot. Alternatively, the support portion 142 may be made of an elastic material of a desired thickness for comfort of the wearer.

The elastic part 144 is made of a soft material to absorb shock and the like.

The contact portion 146 is made of a soft material such as a thin cloth to absorb sweat from the foot while making the wearer feel comfortable, and is attached to the elastic portion 144 by an adhesive.

When the insole assembly 100 is used in a shoe to increase its weight, the lower insole 110 having a desired weight is inserted into the shoe, and then the upper insole 140 is placed on the lower insole 110 in the shoe with the front and rear ends 140a and 140b of the upper insole 140 aligned with the front and rear ends 110a and 110b of the lower insole 110.

Figure 2 is an exploded perspective view of an insole assembly for increasing the weight of an article of footwear according to a second embodiment of the present invention.

As shown in fig. 2, the insole assembly 200 of the present invention comprises: a heavy insole or lower insole 210 made of an extruded resin having a high specific gravity to increase the weight of the footwear or shoe, a shock absorbing member 230 attached at the heel of the lower insole 210, and an upper insole 240 positioned above the lower insole 210.

The lower insole 210 is made of the same material as the lower insole 110 of the first embodiment, but modified in structure.

The lower insole 210 will be described below with reference to fig. 3 to 5, in which fig. 3 is a sectional view of the lower insole shown in fig. 2, fig. 4 is a top view of fig. 3, and fig. 5 is a bottom view of fig. 3.

As shown in fig. 3 to 5, the lower insole 210 is provided with a plurality of front recesses 214, a rear recess 218, and a plurality of longitudinal grooves 216 for connecting the recesses 214 and 218 on the upper surface 212.

A rear recess 218 is engraved on the upper surface 212 or recessed from the upper surface 212 to absorb any impact of landing. Furthermore, posterior concavity 218 is connected to anterior concavity 214 by groove 216, such that pressure applied to posterior concavity 218 during a stride forces air to circulate within the shoe from posterior concavity 218 through groove 216 to anterior concavity 214, while evaporating perspiration from the foot within the shoe and dissipating the heat.

There are a plurality of exposed vertical through holes 220 in the front recess 214. The through holes 220 are connected to a plurality of lateral grooves 226 formed in the lower surface 222 of the lower insole 210. The longitudinal groove 224 is connected to a bottom recess 228, which is formed in the middle of the lower surface 222 and serves as a passage through which air flows from the recess 228 toward the vertical through-hole 220.

In the area of the shoe, on which the load is applied mainly by the front part of the foot, an annular recess 226a is provided to form an air passage that absorbs the landing pressure and impact.

The shock absorbing member 230 is attached at the heel of the lower insole 210 and is made of an elastic member to absorb an impact load applied to the wearer during his/her movement. In addition, the rear corners of the shock absorbing members are rounded to more effectively absorb shock during a step and ensure walking comfort.

The lower insole board 210 is provided with a raised portion 232 at the center of the upper surface 212. The raised portion 232 supports the metatarsal bones while functioning as a cushion (cushion) with the recessed portion 254 of the upper insole 240 (which will be described below).

The upper insole 240 will be described with reference to fig. 6 to 8, in which fig. 6 is a sectional view of the upper insole shown in fig. 2, fig. 7 is a top view of fig. 6, and fig. 8 is a bottom view of fig. 6.

The upper insole 240 integrally has a supporting part 242 attached to the lower insole 210, a resilient part 244 positioned on the supporting part 242, and a sole contacting part 246 positioned on the resilient part 244 to contact the sole of the wearer's foot.

The supporting portion 242 is made of, for example, EVA, of a predetermined thickness to prevent the foot of the wearer from twisting. Alternatively, the support portion 242 may be made of an elastic material of a desired thickness for comfort of the wearer.

The elastic part 244 is made of a soft material to absorb shock or the like.

The contact portion 246 is made of a soft material such as a thin cloth to absorb sweat from the foot while making the wearer feel comfortable, and is attached to the elastic portion 244 by an adhesive.

The upper insole 240 has a stud 252a extending from the front (top front) of the upper surface near the front end 240 a. The upper insole 240 also has a plurality of air discharge holes 248 formed near the front end 240a and a plurality of downward protrusions 250 formed at the bottom front end thereof. Then, the protrusion 250 contacts the upper surface 212 of the lower insole 210 to form a space between the lower surface of the upper insole 240 and the upper surface 212 of the lower insole 210, through which air can flow when a wearer walks. It therefore circulates air within the shoe to evaporate perspiration from the foot and dissipate the heat.

The upper insole 240 is provided with a protrusion 252b extending longitudinally at the middle of the upper surface of the upper insole 240. The raised portion 252b supports the metatarsal bones of the foot to distribute the load to the bottom of the shoe. The bottom of the boss 252b is formed with a recess 254 to receive the boss 232 of the lower insole 210, thereby supporting the metatarsal bones together with the boss 232.

A cavity 256 is formed at the bottom of the upper insole 240 near the heel-contacting rear end 240b of the wearer. The cavity 256 is located at a position corresponding to the rear recess 218 of the lower insole 210, and preferably three grooves 258 are formed corresponding to the longitudinal grooves 216 of the lower insole 210. On a stride, the cavity 256 contracts, forcing air from the cavity 256 to flow forwardly through the recesses 258 and 216 and out through the vent hole 248 toward the front of the foot. In this way, air is circulated within the shoe, while evaporating perspiration from the foot and removing heat.

Figure 9 is a side view of an article of footwear or shoe having an insole assembly 100 or 200 according to the first or second embodiments of the invention placed therein.

As shown in FIG. 9, footwear 10 includes an upper or body 12 for receiving a foot, a midsole 14 for supporting body 12, and an outsole 16 located beneath midsole 14.

The lower insole 110 or 210 and the upper insole 140 or 240 of the insole assembly 100 or 200 are inserted into the footwear 10 and over the midsole 14 in this order to support the feet.

The heavy or lower insole 110 or 210 is preferably manufactured in various weights. For example, the lower insole is made to have different weights such as 200 g, 400 g, 600 g, and 900 g so that the user can select the lower insole of a desired weight to adjust his/her exercise effect.

During the manufacture of the shoe, the last (last) is adjusted according to the wide foot, the narrow foot and the medium-wide foot of different foot widths. If the lower insoles 110 and 210 are manufactured in various thicknesses, shoes of different widths can be manufactured without additionally manufacturing different lasts for the shoes. That is, users of different foot widths can use the same last shoe to fit their feet by selecting the appropriate thickness of the lower insole 110 or 210 according to their foot width. Further, substantially the same effect can be expected by taking out the upper insole 140 or 240 and using only the lower insole 110 or 21O.

The manufacturing process of the heavy or lower insole of the present invention is as follows: mixing natural rubber with synthetic rubber of nitrile rubber and butadiene rubber, and then mixing with high specific gravity filler BaSO₄And (4) mixing. The mixture was extruded with a roll press to improve molecular mass as well as plasticity and viscosity. The compressed mixture was further mixed with ZnO, S, stearic acid and a vulcanization accelerator, and then was pressurized again to make a sheet about 5 mm thick.

Pressing at about 6-8kgf/cm²At a temperature in the range of from 130 ℃ to 160 ℃ for a period of from 5 minutes to 8 minutes.

In the sheet prepared as above, the upper sheet preferably has a hardness of about 45 or less, and the other sheets preferably have a hardness of about 50 to 60, more preferably about 55. The upper sheet has a relatively low stiffness to absorb load impacts applied to the wearer's foot and joints as much as about 4 to 5 times the weight of the wearer when walking.

These sheets are stacked in the desired number (typically 4 to 6 layers), loaded into a mold, and then heated to form the shape of the insole.

Then, the insole has a specific gravity of about 2.0 or more, and has a different mass of about 300 to 1200 g according to the amount of the filler at a size of 255 mm, and thus can be used as a weight increasing means of the footwear. For reference, a typical insole has a specific gravity of about 0.4 to 0.6.

Table 1 reports the physical properties of the heavy insole produced in the above process.

TABLE 1

Test items	Unit of	Results	Test Manual (Test Manual)
				Tensile strength	kgf/cm	16	KS M 6518
Elongation percentage	％	410	KS M 6518
				Tear strength	kgf/cm	9.2	KS M 6518
Specific gravity of		2.38	KS M 6518
				Hardness (A-type)	Scale	55±1	KS M 6518
Elasticity (Steel ball falling)	％	17	KS M 6518

Fig. 10 is a side view of a heavy article of footwear for enhancing the effectiveness of an exercise according to a third embodiment of the present invention. As shown in fig. 10, the heavy footwear or shoe 300 of the present invention includes a main body 320 of an upper for receiving a foot, a midsole 330 connected to the main body 320 to support the foot, and a bottom sole or outsole 340 located below the midsole 330. The midsole 330 and the outsole 340 are made of various materials and have various thicknesses according to the type and use of the shoe. In addition, an insole 350 (shown in phantom) is placed over midsole 330 to provide cushioning to the bottom of the wearer's foot.

The third embodiment of the present invention has a technical feature of increasing the weight of the shoe 300 by forming the midsole 330 and/or the outsole 340 of the shoe 300 with the high specific gravity of the extruded resin or inserting the weight gain made of the high specific gravity of the extruded resin into the midsole 330 and/or the outsole 340. The extrusion resin having a high specific gravity preferably has a specific gravity of about 2 or more, and contains nitrile rubber, butadiene rubber, barium sulfate (BaSO) as a filler having a high specific gravity₄) Lead oxide (Pb)₃O₄) ZnO, S, stearic acid and a vulcanization accelerator.

Fig. 11 is an exploded perspective view of a heavy article of footwear or shoe 300 in accordance with a third embodiment of the present invention. Referring to fig. 11, the heavy shoe 300 according to the third embodiment of the present invention includes an upper or main body 320 for receiving a foot, a midsole 330 connected to the main body 320 to support the foot, and an outsole 340 located under the midsole 330. The midsole 330 and the outsole 340 are made of various materials and have various thicknesses according to the type and use of the shoe. Further, for convenience, an insole 350 placed above the midsole 330 to provide cushioning to the sole of the wearer's foot is not shown.

The midsole 330 has a weight 332 made of a high specific gravity extrusion resin and a shell 334 for receiving the weight 332. The weight 332 and the shell 334 may be made as separate components before the weight 332 and the shell 334 are assembled together by a suitable method, such as with an adhesive. Alternatively, the entire midsole 330 may be formed of a high specific gravity extrusion resin or rubber.

The weight increasing member 332 is preferably formed of an extruded resin having a high specific gravity of about 2 or more, and the specific gravity thereof is determined according to the desired weight of the footwear 300 and the thickness of the midsole 330. The high specific gravity extrusion resin preferably has a specific gravity of about 2 or more and contains a nitrile rubber, a butadiene rubber, BaSO as a filler having a high specific gravity₄、Pb₃O₄ZnO, S, stearic acid and a vulcanization accelerator.

The outsole 340 may be made of general purpose rubber or synthetic resin, or may be made of abrasion resistant rubber or synthetic resin to prevent easy abrasion or tearing.

Fig. 12 is an exploded perspective view of a heavy article of footwear or shoe 400 according to a fourth embodiment of the invention. Referring to fig. 12, the heavy shoe 400 according to the fourth embodiment of the present invention includes a main body 420 of an upper for receiving a foot, and an outsole 440 coupled to the main body 420 to support the foot. The outsole 440 has a midsole formed integrally therewith, is made of various materials, and has various thicknesses according to the type and use of the shoe. Also, for convenience, an insole for cushioning a wearer's sole of the foot, which is placed above the outsole 440, is not shown.

The outsole 440 has a weight 442 made of a high specific gravity compressed resin and a case 444 for accommodating the weight 442. The weight 442 and the shell 444 may be made as separate parts before the weight 442 and the shell 444 are assembled into a single piece by a suitable method, such as with an adhesive.

The weight 442 is preferably formed of an extruded resin having a high specific gravity of about 2 or more, and the specific gravity thereof is determined according to the desired weight of the shoe 400 and the thickness of the outsole 440. The high specific gravity extrusion resin preferably contains nitrile rubber, butadiene rubber, BaSO as a high specific gravity filler₄、Pb₃O₄ZnO, S, stearic acid and a vulcanization accelerator. Further, the case member 444 may be made of general-purpose rubber or synthetic resin, or made of abrasion-resistant rubber or synthetic resin to prevent easy abrasion or tearing.

Alternatively, the entire outsole may be formed of a high specific gravity resin or rubber. That is, the high specific gravity rubber provides not only a large weight but also high abrasion resistance, and thus can be used as an excellent housing member by itself.

Fig. 13 is an exploded perspective view of a heavy article of footwear or shoe 500 in accordance with a fifth embodiment of the invention. Referring to fig. 13, the heavy shoe 500 according to the fifth embodiment of the present invention includes a main body 520 of an upper for receiving a foot, an underlying midsole 530 connected to the main body 520 to support the foot, and a bottom sole or outsole 540 under the midsole 530. The midsole 530 and the outsole 540 are made of various materials and have various thicknesses according to the type and use of the shoe. Also, for convenience, an insole positioned above the midsole 530 to provide cushioning to the sole of the wearer's foot is not shown.

The outsole 540 has a weight 542 made of a high specific gravity extruded resin and a case 544 for receiving the weight 542. The weight 542 and the casing 544 may be made as separate components before the weight 542 and the casing 544 are assembled together by a suitable method, such as by using an adhesive.

The weighting member 542 is preferably formed by extrusion having a high specific gravity of about 2 or moreThe resin is formed, and its specific gravity is determined according to the desired weight of the shoe 500 and the thickness of the outsole 540. The high specific gravity extrusion resin preferably contains nitrile rubber, butadiene rubber, BaSO as a high specific gravity filler₄、Pb₃O₄ZnO, S, stearic acid and a vulcanization accelerator. Further, the case member 544 may be made of general-purpose rubber or synthetic resin, or made of abrasion-resistant rubber or synthetic resin to prevent easy abrasion or tearing.

Alternatively, the entire outsole may be formed of a high specific gravity resin or rubber. That is, the high specific gravity rubber provides not only a large weight but also high abrasion resistance, and thus can be used as an excellent housing member by itself.

As described above, a weight member made of a high specific gravity resin may be inserted into the outsole and/or the midsole, or the entire outsole and/or the midsole may be made of a high specific gravity compressed resin to increase the weight of the shoe, thereby remarkably enhancing the wearer's exercise effect.

The manufacturing process of the midsole and/or outsole for use in the heavy shoes according to the third to fifth embodiments of the present invention will be described below.

Mixing natural rubber with synthetic rubber of nitrile rubber and butadiene rubber, and then mixing with high specific gravity filler BaSO₄And (4) mixing. The mixture was extruded with a roll press to improve molecular mass, as well as moldability and viscosity. The pressed mixture is mixed with ZnO, S, stearic acid, a vulcanization accelerator, and then pressed again to form a sheet having a predetermined thickness, preferably about 5 mm thick.

Pressing at about 6 to 8kgf/cm²And a temperature range of 130 ℃ to 160 ℃ for 5 minutes to 8 minutes.

These sheets are made to have a hardness of about 45 to 60, preferably about 50 to 55.

These sheets are stacked in a desired number of layers, loaded into a mold, and then heated to form the shape of the insole.

The weight member manufactured as above has a specific gravity of about 2.0 or more and has different mass of 300 g to 1200 g according to the amount of the filler at a size of 255 mm, and thus can be used as a weight increasing means for shoes.

The weight elements produced by the above process had the physical properties as reported in table 1 above.

Industrial applications

As described above, an insole assembly for increasing the weight of footwear (e.g., shoes) according to the present invention is made of only synthetic rubber and/or resin to overcome various problems caused by a metal member inserted into an outsole and/or an insole of a shoe.

The insole assembly of the present invention can also be cost-effective, as a mold for the weight elements made of metal is not required, and the assembly process is simplified.

Because metal is no longer used, the insole assembly of the present invention eliminates the inconvenience of the wearer removing the shoe or removing the metal piece while passing through the airport scanner. The shoe does not make noise even if the outsole is partially worn while walking, thereby being capable of extending the life thereof. Further, since rust does not occur even if washed with water for a long time, the shoe is not stained (rusted).

Meanwhile, natural perfume and herb (vanilla) or medicinal powder can be added into the synthetic resin or rubber of the insole to benefit the health of feet.

In addition, the heavy footwear according to the present invention is made of only synthetic rubber and/or resin to overcome various problems caused by a metal member inserted into the outsole and/or insole of the shoe.

The heavy footwear of the invention also allows cost savings, since no molds for the weight elements made of metal are required, and the assembly process is simplified.

Because metal is no longer used, the heavy footwear of the present invention eliminates the inconvenience of the wearer removing the shoe or removing the metal piece while passing through the airport scanner. The shoe does not make noise even if the outsole is partially worn while walking, thereby being capable of extending the life thereof. Further, since rust does not occur even if washed with water for a long time, the shoe is not stained (rusted).

While the invention has been shown and described with respect to the preferred embodiments, it will be understood by those skilled in the art that changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims (21)

1. An insole assembly (100, 200) for increasing the weight of an article of footwear, comprising:

a lower insole (110, 210) made of an extruded resin having a high specific gravity; and

an upper insole (140, 240) disposed above the lower insole (110, 210).

2. The insole assembly according to claim 1, wherein the lower insole (110, 210) is made of a molded resin.

3. The insole assembly of claim 2, wherein the molded resin has a specific gravity of at least 2.

4. The insole assembly according to claim 1, wherein the lower insole (210) has a front recess (214), a rear recess (218), and a plurality of longitudinal grooves (216) for connecting the front recess (214) and the rear recess (218) at an upper surface (212) thereof.

5. The insole assembly according to claim 1, wherein the lower insole (210) has longitudinal grooves (224) and lateral grooves (226) formed at a lower surface (222) thereof, and a recess (228) formed at a central portion of the lower surface (222) and connected to the longitudinal grooves (224).

6. The insole assembly according to claim 1, wherein the lower insole (210) has a plurality of through holes (220) for connecting an upper surface (212) and a lower surface (222) thereof.

7. The insole assembly according to claim 1, wherein the upper insole (240) has a non-slip protrusion (252a) at an upper surface front portion thereof.

8. The insole assembly according to claim 1, wherein the upper insole (240) has vent holes (248) perforated vertically at a front portion thereof and protrusions (250) formed at a front portion of a lower surface thereof.

9. The insole assembly according to claim 1, wherein the upper insole (240) has a protrusion (252b) extending longitudinally in the middle of its upper surface to support metatarsals.

10. The insole assembly according to claim 1, wherein the upper insole (240) has a hollow recess (256) formed at a lower surface rear portion thereof.

11. The insole assembly according to claim 1, wherein the upper insole (140, 240) has a support portion (142, 242) made of ethylene vinyl acetate copolymer for preventing the foot of the wearer from twisting and a contact portion (146, 246) made of a thin cloth and located above the support portion (142, 242).

12. The insole assembly according to claim 1, further comprising a shock absorbing member (130, 230) attached to a rear end (110b, 210b) of the lower insole (110, 210).

13. An article of heavy weight footwear comprising:

a body (320, 420, 520) for receiving a foot;

an outsole (340, 440, 540) attached to the body (320, 420, 520) for supporting the foot, at least a portion of the outsole being made of an extruded resin having a high specific gravity; and

an insole positioned above the outsole (340, 440, 540) within the body (320, 420, 520).

14. The heavy weight footwear according to claim 13, wherein the entirety of the outsole (440, 540) is made of a high specific gravity compressed resin.

15. The heavy weight footwear according to claim 13, wherein the high specific gravity compressed resin is inserted into the outsole (440, 540).

16. The heavy weight article of footwear of claim 13, further comprising a midsole (330, 530) interposed between the outsole (340, 540) and the body (320, 520), at least a portion of the midsole (330, 530) being made of a high specific gravity extruded resin.

17. The heavy weight footwear according to claim 16, wherein the whole of the midsole (330, 530) is made of a high specific gravity compressed resin.

18. The heavy weight footwear according to claim 16, wherein the high specific gravity compressed resin is inserted into the midsole (330, 530).

19. An article of heavy weight footwear comprising:

a body (320) for receiving a foot;

a midsole (330) attached to the body (320) for supporting the foot, at least a portion of the midsole being made of an extruded resin having a high specific gravity;

an outsole (340) attached to a lower surface of the midsole; and

an insole positioned within the body above the midsole.

20. The heavy weight footwear according to claim 19, wherein the whole of the midsole is made of a high specific gravity compressed resin.

21. The heavy weight footwear according to claim 19, wherein the high specific gravity compression resin is inserted into the midsole (330).