Abstract
A pneumatic energy conversion mechanism for use with footwear generates electricity from foot-strikes. The mechanism comprises: at least one air-chamber with an outlet disposed to be compressed on foot strikes and decompressed when the foot is lifted; a micro-electrical generator supported within a support air tube pneumatically connected with the at least one air-chamber's outlet, at its one end, while having its other end open; at least one unidirectional axial-flow micro-turbine, such as the wells turbine, having all its blades exposed to the airflow, thus providing a powerful torque the same micro-electrical generator.
Claims
1. A pneumatic energy converter mechanism for footwear comprising: at least one compressible and decompressible air-chamber an outlet; said air-chamber secured within the footwear, producing an airflow with a one direction on a said air-chamber's compression and with an opposite to said one direction on a said air-chamber's decompression; a micro-electrical rotational generator supported within a support air tube having a first end and an open second end; a means for pneumatically connecting said at least one air-chamber's outlet with said support air tube's first end; at least one unidirectional axial-flow micro-turbine attached for rotation on said micro-electrical rotational generator, within said support air tube; said at least one unidirectional axial-flow micro-turbine having a set of blades all being exposed at the same time to said air-flow, whereby said at least one unidirectional axial-flow micro-turbine always rotates unidirectionally when exposed to said airflow with said one direction and said opposite to said one direction and captures said air-flow with said set of blades all being exposed at the same time to said airflow, generating a powerful torque for said micro-electrical rotational generator.
2. The pneumatic energy converter mechanism of claim 1 wherein: said at least one unidirectional axial-flow micro-turbine is a unidirectional Wells turbine.
3. The pneumatic energy converter mechanism of claim 1 wherein: said at least one compressible and decompressible air-chamber with is two compressible and decompressible air-chambers secured in said footwear under the heel and the ball of the foot respectively.
4. The pneumatic energy converter mechanism of claim 1 further including: a flexible foam material contained within said at least one compressible and decompressible air-chamber.
5. A pneumatic energy converter mechanism for footwear comprising: a heel compressible and decompressible air-chamber with a heel outlet tube having a heel open end, secured within the footwear within the heel portion of the footwear, producing a heel airflow with a heel one direction on a heel compression of said heel air-chamber and a heel opposite to said heel one direction on a heel decompression of said heel air-chamber; a ball-of-foot compressible and decompressible air-chamber with a ball-of-foot outlet tube having a ball-of-foot open end, secured within the footwear within the ball portion of the footwear, producing a ball-of-foot airflow with a ball-of-foot one direction on a ball-of-foot compression of said ball-of-foot air-chamber and a ball-of-foot opposite to said ball-of-foot one direction on a ball-of-foot decompression of said ball-of-foot air-chamber; at least one heel unidirectional axial-flow micro-turbine being housed within a heel part of said heel outlet tube with a heel part longitudinal axis of symmetry, to axially receive said heel airflow; at least one ball-of-foot unidirectional axial-flow micro-turbine being housed within a ball-of-foot part of said ball-of-foot outlet tube with a ball-of-foot part longitudinal axis of symmetry, to axially receive said ball-of-foot airflow; said heel part longitudinal axis of symmetry coincides with said ball-of-foot part longitudinal axis of symmetry; a micro-rotational generator with a micro-rotational generator shaft coinciding with said heel and ball-of-foot part longitudinal axes, and being extended within said heel part of said heel outlet tube and said ball-of-foot part of said ball-of-foot outlet tube, and having attached said at least one heel and ball-of-foot axial-flow micro-turbines, wherein said micro-rotational generator is securely supported on said heel part of said heel outlet tube and said ball-of-foot part of said ball-of-foot outlet tube, whereby said heel and ball-of-foot airflows do not interfere with each other, while powering said micro-rotational generator.
6. The pneumatic energy converter mechanism of claim 5 further including: a jacket support tube for securely aligning said micro-rotational generator shaft with said heel part and ball-of-foot part longitudinal axes of symmetry.
7. The pneumatic energy converter mechanism of claim 5 wherein: said at least one heel and ball-of-foot axial flow micro-turbines are unidirectional Wells turbines.
Description
LIST OF FIGURES
(1) FIG. 1 shows a perspective view of footwear with the electricity generation mechanism.
(2) FIG. 2 shows only the electricity generation mechanism embedded in the footwear of FIG. 1.
(3) FIG. 3 shows a part of the support tube including two axial-flow unidirectional turbines (Wells) rotationally attached on a micro-electrical generator.
(4) FIG. 4 shows the footwear embedded electricity generation mechanism with independent airflow pathways.
(5) FIG. 5 shows the embedded electricity generation of mechanism of FIG. 4 reinforced with a support jacket tube which further secures axial alignment of the electricity generation parts.
DETAILED DESCRIPTION
(6) The present disclosure describes a pneumatic electricity generation mechanism embedded in footwear. The mechanism includes at least one air-chamber with an outlet, which is placed so that it is compressed by the foot, while walking running, jumping and in general when the foot applies pressure, such as the pressure exerted on the footwear by the heel or the ball of the foot. When the air chamber is compressed, an airflow exits the air chamber through its outlet. When the foot is lifted the air-chamber decompresses. When the air chamber decompresses an air flow enters the air chamber through the outlet, at the opposite direction from the airflow created during the air-chamber compression. The air-chamber can be made by an elastomeric material such as the one used for air-bulbs in sphygmomanometers, so that after compression and during decompression the air-chamber returns to the form it had before compression. To return to the uncompressed form, the air-chamber may further contain decompression means, such as a sponge or flexible foam material or flexible polyurethane foam, which can be compressed on compression and expand back into its initial shape after compression, pushing the internal air chamber walls to return to the uncompressed form; or springs, placed inside the air chamber, which can be compressed and expand back to their initial uncompressed length or state, during decompression, thus pushing the air-chamber's walls, internally, back to the uncompressed form.
(7) FIG. 1 shows a preferred embodiment utilizing two air-chambers, 20 and 30, placed in footwear 10 to be compressed by the heel and the ball of the foot respectively. FIG. 1 also shows air outlets 25 and 35, pneumatically connected to a Y-joint pipe 40, pneumatically connecting outlets 25 and 35 to the one end of support tube 50. Support tube 50 houses the electricity generation mechanism. The airflows created from the compression of chambers 20 and 30 are forced to pass through support tube 50, which has and exit through its open end extension 55. These air flows activate the rotation of axial flow micro-turbines 60 and 65, which are contained for rotation within the support 50, as follows: micro rotational generator 60 is placed inside the support tube and is fixed in position by at least one support, fixed on the tube wall, such as support 75. Support 75 supports the generator 60 so that the generator's shaft coincides with the longitudinal axis of symmetry of the support tube 50. FIG. 3 shows in more detail the micro rotational generator, the generator's rotor shaft, the generator's support bars, which keep it fixed in the center of the support tube and the axial flow unidirectional micro-turbines attached on the generator's rotor shaft.
(8) FIG. 1 shows axial flow micro-turbines 65 and 70 attached for rotation on generator 60. Axial-flow turbines are turbines in which the flow of the working fluid is parallel to the turbine shaft, as opposed to radial turbines where the fluid runs around a shaft, as in a watermill. All the blades of an axial flow turbine are exposed to the working fluid, whereas only a subset of the total number of blades of a radial flow turbine is exposed to the working fluid. The axial-flow turbines occupy less axial space than the radial flow ones, which is very critical for the efficiency of a footwear electricity generating mechanism, as discussed above.
(9) Axial-flow micro-turbines 65 and 70 are additionally of the unidirectional kind, that is, they rotate always in the same direction independently from the direction of the working fluid that crosses and sets in rotation the turbine blades. Axial-fowl turbines are the Wells turbines, which are well known in the art. Micro-turbines 65 and 70 are placed within the support tube 50 to rotate freely without touching the support tube wall. The micro-turbines are attached on the generator's rotor shaft, as shown in more detail in FIG. 3. FIG. 1 further shows support tube 50 which leads to an open ended pipe extension 55. When the air-chambers are compressed, air flows into the support tube 50 with a direction towards the open end 55, while they rotate micro-turbines 70 and 65, which in turn rotate the generator's rotor producing electricity. When the foot is lifted, the air-chambers decompress inhaling air from open end 55 thus creating an airflow, which has the opposite direction from the airflow created by the compression of the air chambers. As micro-turbines are unidirectional, they keep rotating in the same direction as the direction they had during compression.
(10) The preferred embodiment shown in FIG. 1 utilizes two unidirectional micro-turbines. Other preferred embodiments utilize more than two micro-turbines, or only one, depending on the available airflow. All micro-turbines act upon only one generator. This provides with increased torque to the rotor shaft, producing more power. The electricity generated by the micro-generator is provided through cables to an electrical load, such as a battery recharger, mobile phones, RF radios, GPS systems, electronic medical and entertainment devices, electrical resistor foot warmers, light bulbs/LEDs etc. (not shown).
(11) FIG. 2, for more clarity, shows the footwear generation mechanism of FIG. 1 without the footwear. FIG. 3 shows support tube, 250, which houses and supports the electricity generation mechanism, in a preferred embodiment that utilizes two Wells turbines. Micro-generator 260 is securely fixed on support tube 250 with supports 261 and 262. These are fixed on the support tube's wall and the generator's stator wall 264. Axial micro-turbines 270 and 275 are securely attached for rotation on the micro-generator's shaft 263, which in this embodiment extends from both sides. Axial micro-turbines 270 and 275 are attached on shaft 263 with hubs 274 and 279, respectively. Blades or air-foils, such as 273 and 278 are fixed on hubs 274 and 279 respectively. Arrows 252 and 254 show the directions of the oscillating airflow produced by the compression and decompression of the air-chambers. Micro-turbines 270 and 275 are unidirectional Wells turbines. They can freely rotate unidirectionally, inside support tube 250, always in the same direction indicated by arrows 272 and 277. This is succeeded because the micro-turbines 270 and 275 are Wells turbines, which have symmetrical air-foils, such as the air-foils 273 and 278. Other preferred embodiments have more than two micro-turbines. Generator shaft 263 may further be supported for rotation with a bearing support, such as bearing supports 280 and 282, which are fixed in position connected to the support tube 250.
(12) The preferred embodiment of FIG. 4 utilizes two air-chambers with independent air-pathway outlets in order to allow for airflows which do not meet, but act on the same generator. The preferred embodiment shown in FIG. 4, which purposely omitted showing the footwear for more clarity of the mechanism, utilizes four micro-turbines, two for each air path way outlet. Another preferred embodiment utilizes one micro-turbine per air path way outlet. FIG. 4 further shows within the air-pathway, the micro-turbines attached in each side of the generator. The micro-generator stator wall ends are fixed on the air-pathway walls. This preferred embodiment avoids having airflows flowing in opposite directions, at the same time, and having their air particles colliding within the same air-pathway. This further optimizes the power capture of the airflows, as discussed in the Summary section above. Still, this preferred embodiment utilizes only one generator.
(13) FIG. 4 shows, heel area air-chamber 120 and ball of foot area air-chamber 130 having air pathway outlets 121 (the heel air flow) and 131 (the ball-of-foot air-flow) with outlet open ends 125 (heel open end) and 135 (ball-of-foot), respectively. Respectively also they have air-chamber outlet tube support parts 124 (the heel part) and 134 (the ball-of-foot part), each housing a set of two unidirectional axial turbines attached on the generator rotor shaft extension. Also, each outlet tube support part supports, fixed in position, the generator stator wall end 153 and stator wall end 152, of generator 150, respectively. Micro-turbines 155, 160 and 140, 145, are unidirectional turbines, and can be of the Wells turbine kind. These turbines are attached for rotation on the micro-generator shaft 151, which extends from both sides of the micro-generator 150. The longitudinal axes of outlet tube support parts 124 (heel part) and 134 (ball-of-foot part) are aligned in a straight line and are also aligned with micro-generator 150 stator's longitudinal axis and shaft. When heel air-chamber 120 generates a heel air flow with a one direction and at the same time ball of foot air-chamber 130 produces a ball of foot airflow at the opposite direction, these airflows never meet, since their corresponding air-pathways are independent from each other. Therefore, unidirectional turbine pairs 155, 160 and 140, 145, which always rotate in the same direction, receive unobstructed full power potential of each airflow, which leads to a more powerful rotational torque applied to the same shaft of the same micro-generator 150, thus further increasing the system's efficiency.
(14) FIG. 5 shows the same mechanism of FIG. 4 with the addition of a jacket support tube 170. The preferred embodiment of FIG. 5 utilizes jacket support tube 170 to further secure the alignment of the longitudinal axes of outlet tube support parts 124 and 134 along with the micro-generator shaft's 151. At least one support bar 175 supports micro-turbine 150 on the jacket support tube 170 to further stabilize the micro-turbine 150 in position. Jacket support tube 170 further secures the operation of the electricity generation mechanism in the mobile footwear environment, thus lowering maintenance needs and increasing the system's life cycle, which decrease the overall total ownership cost.
