Tire assembly

Abstract

The tire assembly includes a tire attached to a vehicle, a first power generator unit, and a second power generator unit different from the first power generator unit. The first power generator unit has: a power generator disposed on the inner surface of the tire; and a pressing member fixed to the inner surface of the tire on both sides of the power generating body so as to straddle the power generating body in the circumferential direction of the tire, the pressing member being deformable in accordance with the deformation of the tire. The second power generator unit has: a power generator fixed to the inner surface of the tire; and a weight member that overlaps the power generating body from a side opposite to the inner surface with the power generating body therebetween.

Description

Technical Field

[0001] This invention relates to a tire assembly obtained by assembling a power generator inside a tire. Background Technology

[0002] International Publication No. 2022 / 180916 (Patent Document 1) discloses a tire assembly incorporating a contact-type electric generator. This electric generator has a positively charged insulating film and a negatively charged insulating film, and generates an electromotive force by changing the actual contact area of ​​the contact surfaces between the insulating films. In the tire assembly disclosed in Patent Document 1, the electric generator is disposed between the inner surface of the tire and an elastic body disposed on the inner surface of the tire. The elastic body applies force to the electric generator toward the inner surface of the tire. Therefore, the impact of the tire on the road surface can be used efficiently to promote the charging of the insulating films.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2022 / 180916 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Tire assemblies like those in Patent Document 1 primarily utilize changes in tire strain to promote the charging of the insulating film. However, in such structures, depending on the tire's rotational speed, the aforementioned charging-promoting effect is sometimes weak, resulting in insufficient electricity. Therefore, a tire assembly capable of obtaining sufficient electricity regardless of the tire's rotational speed is desired.

[0008] The object of the present invention is to provide a tire assembly that can obtain sufficient electricity over a wider range of rotational speeds.

[0009] Methods for solving problems

[0010] A tire assembly according to a first aspect of the present invention comprises: a tire mounted on a vehicle; one or more first power generator units; and one or more second power generator units, which are different from the first power generator units. The first power generator unit comprises: a power generator disposed on the inner surface of the tire; and a pressing member fixed to the inner surface of the tire on both sides of the power generator in a manner that spans the power generator along the circumference of the tire, and the pressing member is deformable according to the deformation of the tire. The second power generator unit comprises: a power generator fixed to the inner surface of the tire; and a counterweight member overlapping the power generator from a side opposite to the inner surface, separated from the power generator. The generator has: a first component having a first insulating film forming a first surface; and a second component having a second insulating film forming a second surface opposite to and in contact with the first surface. The first component and the second component are configured such that the actual contact area between the first surface and the second surface changes according to the force applied to the first component and the second component. The first insulating film and the second insulating film are configured such that one of them is positively charged and the other is negatively charged due to the change in the actual contact area.

[0011] The tire assembly of the second aspect of the present invention is the tire assembly of the first aspect, wherein the tire assembly has a plurality of the first power generation units, the plurality of the first power generation units comprising: at least one first power generation unit having a counterweight member having a mass M1 disposed between the power generation unit and the pressing member; and at least one first power generation unit having a counterweight member having a mass M2 disposed between the power generation unit and the pressing member, wherein M1 > M2.

[0012] The tire assembly of the third aspect of the present invention is the tire assembly of the first aspect or the second aspect, wherein the tire assembly has a plurality of said second power generation units, the plurality of said second power generation units comprising: at least one second power generation unit having a counterweight component having a mass M3; and at least one second power generation unit having a counterweight component having a mass M4, where M3 < M4.

[0013] The tire assembly of the fourth aspect of the present invention is a tire assembly of any one of the first to third aspects, wherein the tire assembly has a plurality of the second power generation units, the plurality of the second power generation units comprising: at least one second power generation unit having an area of ​​S1 on the first surface and the second surface; and at least one second power generation unit having an area of ​​S2 on the first surface and the second surface, where S1 < S2.

[0014] The tire assembly of the fifth aspect of the present invention is a tire assembly of any one of the first to fourth aspects, wherein the tire assembly further comprises one or more circuits that receive power supply from the first power generation unit and the second power generation unit respectively, and are connected to an external computer in a manner capable of data communication.

[0015] The tire assembly of the sixth aspect of the present invention is a tire assembly of any one of the first to fifth aspects, wherein the first power generation unit, the second power generation unit, and the circuit are distributed at four or more locations along the circumference of the tire.

[0016] The tire assembly of the seventh aspect of the present invention is a tire assembly of any one of the first to sixth aspects, wherein the first power generation unit, the second power generation unit, and the circuit are distributed at six or fewer locations along the circumference of the tire.

[0017] The tire assembly of the eighth aspect of the present invention is a tire assembly of any one of the first to seventh aspects, wherein the tire assembly further has a counterweight that reduces the mass difference of the dispersedly arranged first power generation unit, the second power generation unit, and the circuit.

[0018] The tire assembly of the ninth aspect of the present invention is a tire assembly of any one of the first to eighth aspects, wherein at least one of the first power generation unit, the second power generation unit, and the circuit is disposed at a position offset from the portion in which the tire is equally divided N times along the circumferential direction.

[0019] The tire assembly of the tenth aspect of the present invention is a tire assembly of any one of the first to ninth aspects, wherein the pressing component comprises at least one of rubber, thermoplastic elastomer, thermoplastic resin and thermosetting resin.

[0020] The tire assembly of the 11th aspect of the present invention is a tire assembly of any one of the 1st to 10th aspects, wherein the pressing component comprises a composite material of rubber and carbon fiber.

[0021] The tire assembly of the 12th aspect of the present invention is a tire assembly of any one of the 1st to 11th aspects, wherein the computer is configured to monitor at least one of the air pressure of the tire, the internal temperature of the tire, and the rotational speed of the tire.

[0022] In a method for manufacturing a tire assembly according to a 13th aspect of the present invention, the tire assembly includes: a tire mounted on a vehicle; and a power generator, the power generator including: a first component having a first insulating film forming a first surface; and a second component having a second insulating film forming a second surface opposite to and in contact with the first surface, the first component and the second component being configured such that the actual contact area between the first surface and the second surface changes according to a force applied to the first component and the second component, and the first insulating film and the second insulating film being configured such that one becomes positively charged and the other becomes negatively charged due to the change in the actual contact area, wherein the method for manufacturing the tire assembly includes the following steps:

[0023] Prepare the tires;

[0024] Prepare at least three power generating units, including a first power generating unit, a second power generating unit, and a third power generating unit; and

[0025] The at least three generators are respectively disposed on the inner surface of the tire.

[0026] The step of distributing the at least three generators on the inner surface of the tire includes the following steps:

[0027] A pressing member capable of deforming according to the deformation of the tire is fixed to the inner surface of the first power generator on both sides of the first power generator in such a way that it spans the first power generator along the circumference of the tire, and a first counterweight member having a first mass is arranged between the first power generator and the pressing member so that the power generation of the first power generator reaches its peak in the first speed region of the rotational speed of the tire.

[0028] A second counterweight component having a second mass is overlapped with the generator from the side opposite to the inner surface, separated by the generator, so that the power generation of the second generator reaches its peak in the second speed region of the tire's rotational speed; and

[0029] The other pressing components are fixed to the inner surface of the tire on both sides of the third power generator in a manner that spans the third power generator along the circumference of the tire. A third counterweight component with a third mass smaller than the first mass is arranged between the third power generator and the other pressing components, so that the power generation of the third power generator reaches its peak in the third speed region of the tire's rotational speed; or,

[0030] A fourth counterweight component, having a fourth mass greater than the second mass, overlaps the third power generator from the side opposite to the inner surface, separated by the third power generator, so that the power generation of the third power generator reaches its peak in the third speed region of the tire's rotational speed. The first speed region is a region with a speed lower than the third speed region, and the third speed region is a region with a speed lower than the second speed region.

[0031] Invention Effects

[0032] According to the present invention, a tire assembly capable of receiving sufficient electricity over a wider range of rotational speeds is provided. Attached Figure Description

[0033] Figure 1 This is a diagram showing the tire assembly of the first embodiment installed in a vehicle.

[0034] Figure 2 This is an unfolded view of the tire assembly according to the first embodiment.

[0035] Figure 3 This is a longitudinal sectional view of the tire assembly according to the first embodiment.

[0036] Figure 4 This is a cross-sectional view of the power generator according to the first embodiment.

[0037] Figure 5 This diagram illustrates the principle of charging of a power-generating body.

[0038] Figure 6 It is a graph that shows the inventor's insights based on the results of the experiment.

[0039] Figure 7A This is a diagram illustrating the actions in Unit 1.

[0040] Figure 7B This diagram illustrates the actions in Unit 2.

[0041] Figure 8 This is a longitudinal sectional view of the tire assembly according to the second embodiment.

[0042] Figure 9 It is a graph that shows the inventor's insights based on the results of the experiment.

[0043] Figure 10 This is a longitudinal sectional view of the tire assembly according to the third embodiment.

[0044] Figure 11 It is a graph that shows the inventor's insights based on the results of the experiment.

[0045] Figure 12This is a longitudinal sectional view of the tire assembly according to the fourth embodiment.

[0046] Figure 13 This is a development diagram of a modified tire assembly.

[0047] Figure 14 This is a diagram showing the structure of the experimental setup.

[0048] Figure 15 This is a graph representing the results of Experiment 2.

[0049] Figure 16 This is a graph representing the results of Experiment 3. Detailed Implementation

[0050] Hereinafter, tire assemblies according to some embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, the dimensions of the various elements in the drawings are sometimes exaggerated for ease of explanation.

[0051] A. Implementation Method 1

[0052] <1. Overall Structure>

[0053] Figure 1 This diagram illustrates the installation of the tire assembly 1 according to the first embodiment of the present invention on the wheel rims (hereinafter also referred to as "wheels") of a vehicle 8. The type of vehicle 8 is not particularly limited, but in this embodiment it is a four-wheeled vehicle having a left front wheel FL, a right front wheel FR, a left rear wheel RL, and a right rear wheel RR. The tire assembly 1 of this embodiment is installed on the wheels FL, FR, RL, and RR of the vehicle 8 in a state of being assembled onto the wheel rims respectively.

[0054] Vehicle 8 is equipped with an on-board system 9 (hereinafter sometimes simply referred to as "System 9"). System 9 is configured to monitor the state of tire assembly 1 (or, tires 2 included in tire assembly 1), such as monitoring at least one of the following: air pressure, internal temperature, and rotational speed of tire assembly 1. That is, System 9 can be a known TPMS (Tire Pressure Monitoring System) or TMS (Tire Monitoring System). System 9 is configured to include at least one of an air pressure sensor, a temperature sensor, and a rotational speed sensor installed on the wheel or tire assembly 1. Tire assembly 1 is configured to generate electricity during the operation of vehicle 8 and supply power to the sensors and other devices included in System 9.

[0055] System 9 may also include a control device 80 mounted on vehicle 8, capable of wired or wireless data communication with the aforementioned sensors. The control device 80, as hardware, may be a microcomputer or similar device, and can be pre-installed in vehicle 8 or installed retrofitted thereafter. The control device 80 is configured to acquire at least one of the data points detected by the aforementioned sensors—air pressure, internal temperature, and rotational speed—and monitor at least one of these data points. Furthermore, the control device 80 may also be connected to a display to show the on / off status of the sensors, as well as the data output by the sensors, such as air pressure, internal temperature, and rotational speed.

[0056] <2. Structure of the tire assembly>

[0057] Hereinafter, the structure of the tire assembly 1 of this embodiment will be described with reference to the accompanying drawings. Figure 2 This is a schematic diagram showing the tire assembly 1 unfolded. Figure 3 This is a longitudinal sectional view of the tire assembly 1 (a sectional view obtained by cutting the tread portion 20 in two parts along the circumference). The tire assembly 1 of this embodiment includes a tire 2, two first power generation units 3 (hereinafter also referred to as "first unit 3"), one second power generation unit 4 (hereinafter also referred to as "second unit 4"), rectifier circuits 5A and 5B, a power control circuit 6, and two counterweights 7A and 7B. These components are distributed at four locations along the circumference of the tire 2. Each component will be described below.

[0058] [tire]

[0059] Tire 2 is made of vulcanized rubber and other materials, and is elastic. For example... Figure 2 and Figure 3 As shown, tire 2 has a tread portion 20, a shoulder portion 21, a sidewall portion 22, and a bead portion 23. The tread portion 20 defines the lateral surface of tire assembly 1 and generates friction through contact with the road surface, thus propelling vehicle 8 forward. The shoulder portion 21 is the portion adjacent to the tread portion 20 and the sidewall portion 22. The sidewall portion 22 forms the two sides of the tire assembly 22; to absorb impacts from the road surface, the sidewall portion 22 bends and flexes. The bead portion 23 has a bead line (not shown) internally embedded and is fixed to a rim formed on the periphery of a wheel rim (not shown).

[0060] [Unit 1]

[0061] Unit 1, 3 includes a power generator 10A, a pressing component 30, a counterweight component 31, and a belt 32. The power generator 10A is a device that uses contact to generate electricity, and has a first component 11 and a second component 12 that are rectangular when viewed from above (see reference). Figure 4The detailed structure of the generator 10A will be described later. The first component 11 and the second component 12 are secured by a belt 32 wrapped around them in a stacked state. One side of the substrate of the belt 32 becomes an adhesive surface, and the belt 32 is wound around the generator 10A such that this adhesive surface is bonded to the first substrate 113 of the first component 11 and the second substrate 123 of the second component 12, respectively, as described later. The belt 32 is not particularly limited as long as it has sufficient strength and adhesion, but from the viewpoint of ensuring heat resistance, it is preferable to use a glass cloth tape in the substrate.

[0062] The tape 32 wound around the generator 10A is fixed to the inner surface 200 of the tire tread portion 20 on the substrate side opposite to the adhesive surface. Thus, the generator 10A is positioned on the inner surface 200 of the tire tread portion 20 via the tape 32. Here, the generator 10A can be configured such that either the first component 11 or the second component 12 is located on the inner surface 200 side. Furthermore, the method of fixing the tape 32 to the inner surface 200 is not particularly limited; for example, it can be bonded using an adhesive.

[0063] The counterweight component 31 is a plate-shaped component that has a rectangular appearance approximately the same as that of the generator 10A when viewed from above. The counterweight component 31 is stacked on top of the generator 10A with the central axis A1 of the tire assembly 1 as a reference, positioned radially inward of the generator 10A. In this embodiment, the counterweight component 31 is fixed to the radially inward side of the substrate surface of the belt 32. That is, the counterweight component 31 can be stacked on one side of the first component 11 and the second component 12. The method of fixing the counterweight component 31 to the belt 32 is not particularly limited; for example, it can be bonded using an adhesive. The counterweight component 31 applies a force to the generator 10A that brings the first component 11 and the second component 12 closer together, thereby promoting the generation of electricity by the generator 10A during rotation of the tire assembly 1. To apply a uniform force in the planar direction of the generator 10A, the counterweight component 31 is preferably configured to overlap the first component 11 and the second component 12 entirely. The material constituting the counterweight component 31 is not particularly limited, and can be, for example, metal, resin, rubber, and their composite materials.

[0064] The pressing member 30 is a component fixed to the inner surface 200 along the circumference of the tire 2, spanning the generator 10A and the belt 32. Specifically, both ends of the pressing member 30 along the circumference of the tire 2 are fixed to the inner surface 200 on both sides of the generator 10A and the belt 32. Thus, the generator 10A and the counterweight member 31 are sandwiched between the pressing member 30 and the inner surface 200. The pressing member 30 is made of a material that can deform according to the deformation of the tire 2. Therefore, during the rotation of the tire 2, the shape of the space surrounded by the pressing member 30 and the inner surface 200 changes. Alternatively, the pressing member 30 may not be fixed to the inner surface 200 at both ends in the width direction (along the direction of the central axis A1), and the aforementioned space may be open in the width direction. Furthermore, in this embodiment, the pressing member 30 is configured to integrally cover the generator 10A and the counterweight member 31 from the radially inner side of the tire assembly 1.

[0065] The pressing member 30 is preferably fixed to the inner surface 200 with a tension that moderately inhibits the separation of the first component 11 and the second component 12 of the generator 10A while ensuring sufficient room for deformation of the generator 10A. The pressing member 30 can be fixed, for example, such that when the portion of the tire assembly 1 in which the generator 10A is fixed is placed on a flat surface, the lower surface of the pressing member 30 is separated from the upper surface of the counterweight member 31 by a predetermined distance. This predetermined distance is preferably 0.05 mm or more and 5 mm or less. The method of fixing the pressing member 30 to the inner surface 200 is not particularly limited; for example, it can be bonded using an adhesive.

[0066] The material constituting the pressing member 30 is preferably a material that has flexibility and higher tensile strength, and preferably includes at least one of rubber, thermoplastic elastomer, thermoplastic resin, and thermosetting resin. Furthermore, from the viewpoint of maintaining the mass balance of the tire assembly 1, the material constituting the pressing member 30 is preferably of lower density. Examples of such materials include, for instance, composite materials of rubber and carbon fiber (CFR). The pressing member 30 of this embodiment is a sheet made of CFR. A CFR sheet with a thickness of 1.0 mm has a specific gravity of approximately 1.12 to 1.16 and a tensile strength of approximately 71.4 MPa to 121.3 MPa.

[0067] [Unit 2]

[0068] Unit 2, 4, includes a generator 10B, a counterweight 41, and a belt 42. The generator 10B has the same structure as the generator 10A, and therefore a detailed description of its structure will be provided later. In the generator 10B, as in the generator 10A, the first component 11 and the second component 12 are secured by the belt 42 while being stacked on top of each other. The counterweight 41 is the same as the counterweight 31, and is a plate-shaped component that has a roughly rectangular appearance similar to that of the generator 10B when viewed from above. The belt 42 and the counterweight 41 will be described in the same way as the belt 32 and the counterweight 31, and therefore a further description is omitted.

[0069] Unit 4 differs from Unit 1 3 in that it does not have a pressing component 30. Therefore, as long as the size and density of the generator 10B and the counterweight 41 are the same as those of the generator 10A and the counterweight 31, Unit 4 is lighter than Unit 1 3.

[0070] [Rectifier Circuit]

[0071] Rectifier circuits 5A and 5B are connected to generators 10A and 10B respectively via wires, rectifying the current output from generators 10A and 10B into DC. Each rectifier circuit 5A is connected to each generator 10A, and each rectifier circuit 5B is connected to each generator 10B. Thus, essentially one rectifier circuit is connected to each generator. The rectifier circuits 5A and 5B are not particularly limited; for example, they can be circuits using known diodes. In this embodiment, two rectifier circuits 5A and one rectifier circuit 5B are mounted together on a substrate 5 and fixed to the inner surface 200 in a manner adjacent to the second unit 4. The reason for arranging the rectifier circuits 5A and 5B adjacent to the second unit 4 will be explained later. The rectified current in the rectifier circuits 5A and 5B is sent to the power control circuit 6 via wires.

[0072] [Power supply control circuit]

[0073] The power control circuit 6 is connected to the rectifier circuits 5A and 5B and the system 9. The power control circuit 6 is configured to supply the current rectified by the rectifier circuits 5A and 5B to the system 9 and to control the operation of the system 9. More specifically, the power control circuit 6 has the function of controlling the on / off state of at least one device included in the system 9 and the function of controlling the current supply to ensure stable operation of the device. In this embodiment, the power control circuit 6 is configured to temporarily store the current rectified by the rectifier circuits 5A and 5B in a capacitor, turn on at least one device when the voltage of the capacitor is above a predetermined upper limit value, and turn off the device when the voltage is below a predetermined lower limit value. The device is a sensor, a microcomputer, or a wireless communication device, etc. Additionally, at least one of the aforementioned devices, other than the capacitor, can also be mounted on the substrate on which the power control circuit 6 is mounted.

[0074] [Counterweight]

[0075] Unlike the purpose of pressurizing generators 10A and 10B, counterweights 7A and 7B are configured to suppress radial force variation (RFV) caused by mass imbalance of the tire assembly 1, and to suppress vibration and noise of the tire assembly 1. In this embodiment, among the first unit 3, the second unit 4, and the power control circuit 6, the second unit 4 has the smallest mass, and the power control circuit 6 has the largest mass. Therefore, in this embodiment, in order to reduce the mass difference between the first unit 3, the second unit 4, and the power control circuit 6 by making the masses of the first unit 3 and the second unit 4 close to the mass of the power control circuit 6, each counterweight and the base plate 5 are configured. Specifically, the counterweight 7A is configured adjacent to each first unit 3, and the counterweight 7B and the base plate 5 are configured adjacent to the second unit 4. In addition, the counterweights 7A, 7B, and the base plate 5 can be configured near each generator unit within the range of the "set" described later as a mass point, or they can be configured at a distance from each generator unit. The mass of counterweights 7A and 7B can be appropriately determined based on the mass of unit 3, unit 4, substrate 5 (containing rectifier circuits 5A and rectifier circuits 5B), and power control circuit 6.

[0076] The materials used to constitute counterweights 7A and 7B are not particularly limited and can be appropriately selected. Furthermore, the method of fixing counterweights 7A and 7B to the inner surface 200 is not particularly limited; for example, it can be bonded using an adhesive. Alternatively, counterweight 7A may not be directly fixed to the inner surface 200, but rather fixed to the surface on the side of the central axis A1 of the pressing member 30. In this case, counterweight 7A is preferably fixed to the portion of the pressing member 30 fixed to the inner surface 200 in a manner that does not impede the deformation of the pressing member 30.

[0077] [Configuration]

[0078] The assembly of Unit 1 3 and counterweight 7A, the assembly of Unit 2 4 and counterweight 7B and substrate 5, and the power control circuit 6 can be considered as virtual mass points dispersed along the circumference of tire 2. From the viewpoint of suppressing vibrations of tire assembly 1 caused by higher-order components of RFV, if tire 2 is for passenger cars, the mass of each virtual mass point (the total mass of the components constituting the assembly) is preferably 30g or less; if tire 2 is for large vehicles such as trucks / buses, the mass of each virtual mass point (the total mass of the components constituting the assembly) is preferably 40g or less. Furthermore, in order to consider the above-mentioned assembly as a mass point, it is preferable that the length of each assembly along the circumference of tire 2 is 15% or less relative to the full circumference of the inner surface 200.

[0079] The aforementioned virtual particles are preferably distributed at four or more locations along the circumference of the tire 2, more preferably at four to six locations. This disperses the first-order component of the RFV that affects vibration to the vicinity of the fourth to sixth-order components, which are less likely to affect both vibration and noise, thereby suppressing the adverse effects of the RFV. Furthermore, when the virtual particles are distributed at N locations along the circumference of the tire 2, it is preferable that at least one of these virtual particles is not located at a location where the tire 2 is divided into N equal intervals along the circumference, but rather at a location offset from that location. For example, in Figure 2 and Figure 3 In this configuration, with the position of the first unit 3 and the counterweight 7A as a reference (0°), the second unit 4, the substrate 5, and the counterweight 7B are positioned at 100° instead of 90°. Furthermore, the power control circuit 6 is positioned at 275° instead of 270°. Thus, by positioning at least one of the virtual mass points on the inner surface 200 at a position deviating from the rotational position of 360° / N, the peak value of the Nth-order component of vibration and noise can be mitigated. Additionally, the deviation angle of the amount of deviation from the rotational position of 360° / N is preferably (0.05 × 360° / N) or more and (0.26 × 360° / N) or less.

[0080] Furthermore, the circumferential reference of tire 2 can be set, for example, at the lightest position in the overall mass balance of tire 2. Moreover, tire 2 can be placed on a water platform with its outer side facing upwards, and the reference can be measured with the center of tire 2 aligned with a predetermined position on the platform. The position of the virtual mass point can be determined by the angle relative to this reference.

[0081] <3. Electric Generator>

[0082] The power generators 10A and 10B may be composed of all elements of the same size and material, or at least some of their sizes and materials may differ from each other. The structure shared in the power generators 10A and 10B will be described below. Hereinafter, without specifically distinguishing between the power generators 10A and 10B, they will be collectively referred to as "power generator 10".

[0083] Figure 4 This is a cross-sectional view showing the structure of the power generator 10 according to this embodiment. Figure 4 As shown, the power generator 10 has the following structure: the power generator 10 has a first component 11 and a second component 12, and the components are stacked sequentially. The power generator 10 of this embodiment has a square shape of the same size when viewed from above, but the shape of the power generator 10 is not limited to this. Furthermore, the direction in which the power generator 10 is used is not limited to... Figure 4 direction shown.

[0084] [Component 1]

[0085] The first component 11 comprises a first substrate 113, a first electrode 112, and a first insulating film 111 stacked sequentially. Each element 111 to 113 of the first component 11 has a square shape of the same size when viewed from above. The first substrate 113 is made of a flexible material or a viscoelastic material (e.g., resin or elastomer) to allow it to deform under external force. In this embodiment, the first substrate 113 is made of silicone rubber. A plurality of irregularities are formed on the surface of the first substrate 113 that contacts the first electrode 112. Thus, on the first surface 110 formed from the first insulating film 111 with respect to the first electrode 112, irregularities corresponding to those of the first substrate 113 are reproduced.

[0086] The uneven structure of the first substrate 113 is not particularly limited. For example, the unevenness can be formed regularly in the surface direction of the first substrate 113, or it can be formed randomly to a certain extent. In addition, the cross-sectional shape of the unevenness is not particularly limited.

[0087] The first electrode 112 is used to extract the charge generated on the first insulating film 111 to the outside of the generator 10. The first electrode 112 is disposed on the back side of the first surface 110 in contact with the first insulating film 111. The first electrode 112 can be made of a conductive material. Examples of such materials include conductive films and conductive cloths made of Ag, Cu, etc. The structure of the conductive cloth is not particularly limited. It can be a conductive cloth obtained by metallizing a nonwoven fabric made of a polymer material, or a conductive cloth obtained by mixing metal fibers with fibers made of a polymer material. The first electrode 112 is flexible and can deform in accordance with the deformation of the first substrate 113. In addition, the surface of the first electrode 112 in contact with the first insulating film 111 reproduces the unevenness corresponding to the unevenness of the first substrate 113.

[0088] The first insulating film 111 is a flexible film made of an insulator. In this embodiment, the side of the first insulating film 111 opposite to the first electrode 112 corresponds to the first surface 110. On the first surface 110, a texture corresponding to the texture of the first substrate 113 is formed by the first substrate 113. The first surface 110 faces and contacts the second surface 120 formed by the second insulating film 121 (described later). When the actual contact area between the first surface 110 and the second surface 120 changes due to pressure applied to the generator 10, the first insulating film 111 becomes charged with a polarity opposite to that of the second insulating film 121. That is, when the second insulating film 121 is positively charged, the first insulating film 111 is negatively charged. Conversely, when the second insulating film 121 is negatively charged, the first insulating film 111 is positively charged.

[0089] The ten-point average roughness of the first surface 110 is preferably 100 μm or more and 2 mm or less. Furthermore, the method for measuring the ten-point average roughness follows JIS B 0601:2001.

[0090] Furthermore, the "contact" between the first surface 110 and the second surface 120 is only required to be partial contact; it is also permissible for the first surface 110 and the second surface 120 to not contact each other. In this embodiment, the power generator 10 is configured such that both the first surface 110 and the second surface 120 are square in shape of the same size and overlap entirely. That is, in this embodiment, the power generator 10 has the first surface 110 and the second surface 120 in full-surface contact.

[0091] [Part 2]

[0092] The second component 12 comprises a second substrate 123, a second electrode 122, and a second insulating film 121 stacked sequentially. Each element 121 to 123 of the second component 12 has a square shape of the same size when viewed from above. The second substrate 123 is the same as the first substrate 113, and is made of a flexible material or a viscoelastic material (e.g., resin or elastomer) to allow it to deform under external force. In this embodiment, the second substrate 123 is made of silicone rubber. Multiple irregularities are formed on the surface of the second substrate 123 that contacts the second electrode 122. Thus, on the second surface 120 formed by the second insulating film 121 across the second electrode 122, irregularities corresponding to those of the second substrate 123 are reproduced.

[0093] The uneven structure of the second substrate 123 is not particularly limited. For example, the unevenness can be formed regularly in the surface direction of the second substrate 123, or it can be formed randomly to a certain extent. In addition, the cross-sectional shape of the unevenness is not particularly limited.

[0094] The second electrode 122 is used to extract the charge generated on the second insulating film 121 to the outside of the generator 10. The second electrode 122 is disposed on the back side of the second surface 120 in contact with the second insulating film 121. The second electrode 122 can be made of a conductive material. Examples of such materials include conductive films and conductive cloths made of Ag, Cu, etc. The structure of the conductive cloth is not particularly limited. It can be a conductive cloth obtained by metallizing a nonwoven fabric made of a polymer material, or a conductive cloth obtained by mixing metal fibers with fibers made of a polymer material. The second electrode 122 is flexible and can deform in accordance with the deformation of the second substrate 123. In addition, the surface of the second electrode 122 in contact with the second insulating film 121 reproduces the unevenness corresponding to the unevenness of the second substrate 123.

[0095] The second insulating film 121 is a flexible film made of an insulator different from the first insulating film 111. In this embodiment, the side of the second insulating film 121 opposite to the second electrode 122 corresponds to the second surface 120. On the second surface 120, a bump corresponding to the bump of the second substrate 123 is formed by the second substrate 123. The second surface 120 faces and contacts the first surface 110 formed by the first insulating film 111. When the actual contact area between the first surface 110 and the second surface 120 changes due to pressure applied to the generator 10, the second insulating film 121 becomes charged with a polarity opposite to that of the first insulating film 111. That is, when the first insulating film 111 is positively charged, the second insulating film 121 is negatively charged. Conversely, when the first insulating film 111 is negatively charged, the second insulating film 121 is positively charged.

[0096] The ten-point average roughness of the second surface 120 is preferably 100 μm or more and 2 mm or less. Furthermore, the method for measuring the ten-point average roughness follows JIS B 0601:2001.

[0097] [Materials, etc.]

[0098] The materials constituting the first insulating film 111 and the second insulating film 121 may be selected from, for example, diamond-like carbon (DLC), perfluoropolyether, polymethyl methacrylate, nylon, polyvinyl alcohol, polyester, polyisobutylene, polyurethane (PU), polyethylene terephthalate, polyvinyl butyral, polychloroprene, natural rubber, polyacrylonitrile, polybisphenol carbonate, chlorinated polyether, polyvinylidene chloride, polystyrene, polyethylene, polypropylene, polyimide, polyvinyl chloride, polydimethylsiloxane, polytetrafluoroethylene, tetrafluoroethylene and hexafluoropropylene copolymer, polytetrafluoroethylene / hexafluoropropylene copolymer (FEP), and other materials whose main component is fluorocarbon organic compounds.

[0099] From the viewpoint of increasing the electromotive force of the generator 10, it is preferable to select the paired materials from the above group that are further apart in the charge sequence. Furthermore, either the first insulating film 111 or the second insulating film 121 can be positively charged, and either can be negatively charged. In this embodiment, one of the first insulating film 111 and the second insulating film 121 is made of polyimide, and the other is made of nylon. The insulating film made of polyimide is negatively charged, and the insulating film made of nylon is positively charged.

[0100] At least one of the thickness W1 of the first insulating film 111 and the thickness W2 of the second insulating film 121 is preferably 20 μm or less. More preferably, both thickness W1 and thickness W2 are 20 μm or less. Furthermore, the figures do not necessarily reflect the dimensions of the actual elements of the power generator 10.

[0101] [The principle of charging of generator 10]

[0102] The first insulating film 111 and the second insulating film 121 become energized by operating in the following manner: (e.g.) Figure 4 As shown, both the first surface 110 and the second surface 120 in this embodiment have uneven surfaces, and they are not completely separated even when no external pressure is applied to the generator 10, but rather remain in contact with each other. At this time, the distance (average surface interval) between the average surface of the first surface 110 and the average surface of the second surface 120 is relatively large, which is equivalent to a state where the actual contact area between the first surface 110 and the second surface 120 is relatively small.

[0103] Next, when pressure is applied to the generator 10 in such a way that the first insulating film 111 and the second insulating film 121 are closer together, such as Figure 5As shown, the shapes of the first surface 110 and the second surface 120 change, the unevenness becomes slightly flattened, and the average surface spacing decreases. In other words, the actual contact area increases. Then, when the pressure applied to the generator 10 is removed, the first insulating film 111 and the second insulating film 121 separate again, and the average surface spacing increases. In other words, the actual contact area of ​​the first surface 110 and the second surface 120 decreases. Thus, with the change in actual contact area, the charge on the first insulating film 111 and the second insulating film 121 increases compared to the initial state, inducing more charge in the first electrode 112 and the second electrode 122.

[0104] Furthermore, in the case where at least one of the first surface 110 and the second surface 120 has an uneven structure, the actual contact area changes to a certain extent as the first insulating film 111 and the second insulating film 121 move relative to each other along the surface direction. Therefore, the force applied to the generator 10 is not only the force that increases or decreases the average surface spacing, but also the force that causes the first insulating film 111 and the second insulating film 121 to slide relative to each other along the surface direction, which also contributes to the power generation of the generator 10.

[0105] <4. Working principle of tire assembly>

[0106] The first unit 3 and the second unit 4 of the tire assembly 1 exhibit different behaviors depending on the rotational speed of the tire assembly 1. This allows for the stabilization of the power generation of the tire assembly 1 over a wider range of rotational speeds. The reasons for this are explained below.

[0107] The inventors prepared tire assemblies having only Unit 1 (3) and tire assemblies having only Unit 2 (4), and measured the power generation P [μW] of these tire assemblies at rotational speeds V equivalent to 20 km / h to 120 km / h. The results showed that the speed regions where the peak power generation P occurred in Unit 1 (3) and Unit 2 (4) differed significantly. Figure 6 This is a schematic VP curve diagram representing this situation. (From...) Figure 6 It can be seen that in the speed range of 20km / h to 60km / h, the power generation P of Unit 1 3 is greater, and the peak value of the power generation P of Unit 1 3 appears. However, in the speed range above 60km / h, the power generation P of Unit 2 4 exceeds the power generation P of Unit 1 3, and the peak value of the power generation P of Unit 2 4 appears.

[0108] This indicates that in the low-speed region (below 60 km / h), the presence of the pressing member 30 helps to increase the change in the actual contact area of ​​the generator 10, but in the high-speed region (above 60 km / h), the deformation of the generator 10 is limited by the pressing member 30, and the change in the actual contact area decreases. That is, the change in the actual contact area of ​​the generator 10 assembled on the tire 2 can be caused mainly by the change in the strain of the tire 2 or mainly by the change in the radial acceleration (or centrifugal force) generated in the tire 2. Moreover, it can be said that in the low-speed region where the change in radial acceleration is small, it is preferable to guide the deformation of the generator 10 by the pressing member 30, while in the high-speed region where the change in radial acceleration is large, it is preferable not to limit the deformation of the generator 10 by the pressing member 30.

[0109] Based on the above, the inventors configured the tire assembly 1 to have both a first unit 3 and a second unit 4. Figure 7A This diagram illustrates the movement of the first unit 3 at positions A to E in the figure when the tire assembly 1 rotates on the road surface in the direction of arrow A2. Figure 7B This diagram illustrates the movement of unit 4 at positions A through E as tire assembly 1 rotates on the road surface along the direction of arrow A2. Position A is the position just before tire 2 touches the ground, and position B is the position immediately after tire 2 touches the ground. Position C corresponds to the circumferential center of the contact patch of tire 2. Position D is the position just before tire 2 leaves the road surface, and position E is the position immediately after tire 2 leaves the road surface. Figure 7A and Figure 7B In the curves, the time t=0 is set when either Unit 3 or Unit 4 exists at position C. In these curves, the rotational speed of tire assembly 1 corresponds to 40km / h to 50km / h. Furthermore, the output voltage values ​​are standardized in these curves.

[0110] like Figure 7AAs shown, regarding Unit 1, the output voltage reaches its maximum peak at position C. The reasoning is as follows: First, from position A to position B, in conjunction with the strain of tire 2, the pressing member 30 is compressed circumferentially, thereby separating the first surface 110 and the second surface 120 of the generator 10A. Then, at position C, tire 2 extends circumferentially, and in conjunction with this, the pressing member 30 is stretched sharply to both sides, resulting in the first surface 110 and the second surface 120 approaching each other. Next, from position D to position E, again in conjunction with the strain of tire 2, the pressing member 30 is compressed circumferentially, resulting in the first surface 110 and the second surface 120 separating. Thus, in Unit 1, it is believed that the direction of the force applied to the pressing member 30 at position C is reversed, thereby the output voltage reaches its maximum peak at position C. That is, in Unit 1, the change in the circumferential strain of tire 2 becomes the dominant factor influencing the change in the actual contact area of ​​the generator 10A.

[0111] On the other hand, such as Figure 7B As shown, regarding Unit 2 4, at positions B and D, the absolute values ​​of the output voltage become peaks in opposite directions, resulting in a phase shift compared to Unit 1 3. The reasoning is as follows: From position A to position B, a radial acceleration α is applied to the counterweight 41, causing a change in the actual contact area in the direction where the first surface 110 and the second surface 120 approach each other. Then, during the journey from position B through position C to position D, the main force applied to the counterweight 41 is gravitational acceleration g, causing the first surface 110 and the second surface 120 to separate rapidly. This separation is amplified by the absence of the pressing component 30. Therefore, the change in actual contact area is greatest from position B to position D. Next, from position D to position E, a radial acceleration α is again applied to the counterweight 41, resulting in a change in the actual contact area. That is, in Unit 2 4, the change in the radial acceleration (or centrifugal force) of the tire 2 becomes the dominant cause of the change in the actual contact area of ​​the generator 10B. The greater the rotational speed of the tire assembly 1, the greater the change in radial acceleration. Therefore, it can be said that the change in the actual contact area of ​​the generator 10B increases with a greater rotational speed.

[0112] As described above, the tire assembly 1 achieves sufficient power generation in a larger speed range by having different first units 3 and second units 4.

[0113] B. Second Implementation Method

[0114] Figure 8This is a longitudinal sectional view of the tire assembly 1W according to the second embodiment. The tire assembly 1W of this embodiment differs from tire assembly 1 in that the two first units are first unit 3A and first unit 3B. Hereinafter, the tire assembly 1W will be described focusing on the differences from tire assembly 1. Elements with the same structure as tire assembly 1 will be labeled with the same reference numerals, and their descriptions will be omitted.

[0115] Unit 1, 3A, comprises a generator 10W, a pressing component 30W, a counterweight component 31A, and a belt 32W. These components have the same functions as the generator 10A, pressing component 30W, counterweight component 31A, and belt 32W in Unit 1, and are assembled in the same way as Unit 1, 3. Unit 1, 3B, comprises a generator 10W, a pressing component 30W, a counterweight component 31B, and a belt 32W. These components also have the same functions as the generator 10A, pressing component 30W, counterweight component 31A, and belt 32W in Unit 1, and are assembled in the same way as Unit 1, 3. The mass M1 of the counterweight component 31A is greater than the mass M2 of the counterweight component 31B. That is, M1 > M2. Therefore, in the tire assembly 1W, to correct the mass imbalance of the tire assembly 1W, counterweight 7C is arranged adjacent to Unit 1, 3A, and counterweight 7D is arranged adjacent to Unit 1, 3B. Counterweight 7C is lighter than counterweight 7D.

[0116] Figure 9 Based on experiments conducted by the inventor, this diagram schematically illustrates the rotational speed V (equivalent to km / h) of the tire assembly 1W, the power generation P [μW] of each of the first unit 3A, the first unit 3B, and the second unit 4 within the tire assembly 1W, and their total power generation VP curve. Figure 9 As shown, the peak power generation P of unit 3A occurs near 30 km / h to 40 km / h, the peak power generation P of unit 3B occurs near 60 km / h, and the peak power generation P of unit 4 occurs near 90 km / h to 100 km / h. Thus, units 3A, 3B, and 4 show peak power generation P values ​​corresponding to different rotational speed ranges. Therefore, as a whole, tire assembly 1W maintains a more stable power generation rate, especially in the speed range near 60 km / h, compared to tire assembly 1. Furthermore, according to the inventors' research, by assembling different power generation units separately into the tire and measuring the power generation P corresponding to the rotational speed V of the tire assembly, the VP characteristics of the tire assembly as a whole can be estimated by recalculating the individual power generation P values.

[0117] The actions of units 3A and 3B when tire assembly 1W rotates are related to... Figure 7AThe operation of Unit 3 shown is the same. As described above, the power generation of Unit 3 is mainly caused by the circumferential strain of the tire 2, and the peak power generation occurs in the low-speed region below approximately 60 km / h. However, within the aforementioned low-speed region, in the relatively high-speed region (e.g., 40 km / h to 60 km / h), the contribution of the change in radial acceleration of the tire 2 to the change in the actual contact area of ​​the generator 10W gradually increases. Therefore, in the relatively high-speed region, the lighter the counterweight, the more effectively the contribution of the change in radial acceleration to the change in the actual contact area of ​​the generator 10W can be suppressed, and the contribution of the change in strain of the tire 2 to the change in the actual contact area of ​​the generator 10W can be maintained at a relatively high level. Furthermore, by further increasing the natural frequency of Unit 1, the change in the actual contact area becomes more active in the relatively high-speed region. Thus, in Unit 1 with the same structure, if the mass of the counterweight is reduced, it is also possible to further adjust the speed region where the power generation reaches its peak towards the high-speed side. Conversely, it can be said that if the mass of the counterweight components is further increased, the speed range in which power generation reaches its peak can be further adjusted to the lower speed side.

[0118] According to the inventor's research, in order to maximize the power generation of Unit 3A in the speed range of 20km / h to 40km / h, and maximize the power generation of Unit 3B in the speed range of 50km / h to 60km / h, a 1 / 4 (M2 / M1) 1 / 3. The reason is attributed to the change in the natural frequency of the first unit. In the first unit 3A, the counterweight component 31A jumps at its natural frequency f. n It is expressed by the following formula. In the formula, k is a constant.

[0119] [Formula 1]

[0120]

[0121] On the other hand, when M2 = n × M1, the natural frequency f of the first unit 3B is... bn It is expressed by the following formula.

[0122] [Equation 2]

[0123]

[0124] Therefore, when the rate at which the power generation of Unit 1 3A reaches its peak is set as V (equivalent to km / h), the rate at which the power generation of Unit 1 3B reaches its peak is Vb, which is expressed by the following formula.

[0125] [Formula 3]

[0126]

[0127] Therefore, for example, when V=30, by making M2 1 / 3 to 1 / 5 times M1, Vb can theoretically be adjusted to 52 km / h to 67 km / h. However, when M2 is less than 1 / 3 of M1, the rigidity of the first unit 3B decreases, thus the actual Vb does not exceed 60 km / h, tending to shift towards the lower speed side compared to 60 km / h. Furthermore, setting M2 to 0 leads to an overall decrease in power generation, so making M2 too small is not preferable. Therefore, it is preferable to set it to 1 / 4... (M2 / M1) The 1 / 3 ratio allows for more stable power generation across a wider speed range for the tire assembly 1W, improving its VP characteristics. Furthermore, in Unit 1A and Unit 1B, the components of the generator 10W are identical in size.

[0128] C. Third Implementation

[0129] Figure 10 This is a longitudinal sectional view of the tire assembly 1X according to the third embodiment. The tire assembly 1X of this embodiment differs from tire assembly 1 in that it has one first unit 3, one second unit 4A, and one second unit 4B. Hereinafter, the tire assembly 1X will be described focusing on its differences from tire assembly 1. Elements with the same structure as tire assembly 1 will be labeled with the same reference numerals, and their descriptions will be omitted.

[0130] Unit 2, 4A, includes a generator 10X, a counterweight 41A, and a belt 42X. These components have the same functions as the generator 10B, counterweight 41, and belt 42 in Unit 2, and are assembled in the same way. Unit 2, 4B, includes a generator 10X, a counterweight 41B, and a belt 42X. These components also have the same functions as the generator 10B, counterweight 41, and belt 42 in Unit 2, and are assembled in the same way. The mass M3 of the counterweight 41A is less than the mass M4 of the counterweight 41B, i.e., M3 < M4. To correct the mass imbalance of the tire assembly 1X, counterweights 7E and 7F are appropriately positioned near Unit 2, 4A, and Unit 2, 4B, respectively. Here, in the tire assembly 1X, the base plate 5, which is equipped with one rectifier circuit 5A and two rectifier circuits 5B, is arranged adjacent to the second unit 4A. Therefore, the mass of the counterweights 7E and 7F is also set taking into account the mass of the base plate 5 and the rectifier circuits 5A and 5B. The rectifier circuit 5A is connected to the generator 10A, and the rectifier circuits 5B are connected to the generators 10X of the second unit 4A and the second unit 4B, respectively.

[0131] Figure 11Based on experiments conducted by the inventors, this diagram schematically illustrates the rotational speed V (equivalent to km / h) of the tire assembly 1X, the individual power generation P [μW] of the first unit 3, the second unit 4A, and the second unit 4B within the tire assembly 1X, and their total power generation VP curve. Figure 11 As shown, the peak power generation P of unit 3 occurs around 30 km / h to 40 km / h, the peak power generation P of unit 4B occurs around 60 km / h to 80 km / h, and the peak power generation P of unit 4A occurs around 90 km / h to 100 km / h. Thus, unit 3, unit 4A, and unit 4B show the peak power generation P corresponding to different rotational speed regions. Therefore, as a whole, tire assembly 1X can maintain a more stable power generation in the speed region around 60 km / h compared to tire assembly 1.

[0132] The actions of units 4A and 4B during the rotation of tire assembly 1X are related to... Figure 7B The operation of the second unit 4 shown is the same. As mentioned above, the power generation of the second unit 4 is mainly caused by the change in radial acceleration (or centrifugal force) generated in the tire 2. In the second unit 4B, which has a larger counterweight 41B, a larger radial acceleration is applied to the power generator 10X, so the actual contact area is more easily varied. Furthermore, by further reducing the natural frequency of the second unit 4B, the change in actual contact area becomes more active in the relatively low-speed region (e.g., 60 km / h to 80 km / h) within the aforementioned high-speed region. However, in the aforementioned high-speed region, the following performance also deteriorates in the relatively high-speed region (e.g., above 80 km / h), and the actual contact area is not easily varied, so the speed region where the power generation reaches its peak is 60 km / h to 80 km / h. Thus, in the second unit with the same structure, if the mass of the counterweight is further increased, it is also possible to further adjust the speed region where the power generation reaches its peak towards the low-speed side. Conversely, it can be said that if the mass of the counterweight is reduced, the speed region where the power generation reaches its peak shifts further towards the high-speed side.

[0133] According to the inventors' research, in order to ensure that the power generation of the second unit 4A reaches its peak in the speed range of 80 km / h and above, and that the power generation of the second unit 4B reaches its peak in the speed range of 60 km / h to 80 km / h, a speed of 1.5 is preferred. (M4 / M3) 8. Therefore, the overall power generation of the tire assembly 1X can be stabilized over a wider speed range, improving the VP characteristics of the tire assembly 1X. Furthermore, in Units 2A and 2B, the dimensions of each component of the power generator 10X are identical.

[0134] D. Implementation Method 4

[0135] Figure 12 This is a longitudinal sectional view of the tire assembly 1Y according to the fourth embodiment. The tire assembly 1Y of this embodiment differs from tire assembly 1 in that it has one first unit 3, one second unit 4C, and one second unit 4D. Hereinafter, the tire assembly 1Y will be described focusing on its differences from tire assembly 1. Elements with the same structure as tire assembly 1 will be labeled with the same reference numerals, and their descriptions will be omitted.

[0136] Unit 2, 4C, has a generator 10Y, a counterweight 41Y, and a belt 42Y. These components have the same functions as the generator 10B, counterweight 41, and belt 42 of Unit 2, and are assembled in the same way as Unit 2, 4. Unit 2, 4D, has a generator 10Z, a counterweight 41Z, and a belt 42Y. These components also have the same functions as the generator 10B, counterweight 41, and belt 42 of Unit 2, and are assembled in the same way as Unit 2, 4. The area of ​​the first and second surfaces of the generator 10Y is S1, and the area of ​​the first and second surfaces of the generator 10Z is S2, where S1 < S2. Furthermore, the counterweights 41Y and 41Z are formed according to the dimensions of the generators 10Y and 10Z, respectively, and the areas of their main surfaces (the surfaces perpendicular to the radial direction of the tire 2) are approximately the same as S1 and S2, respectively. Furthermore, counterweight components 41Y and 41Z are configured to have the same mass per unit area. To correct the mass imbalance of the tire assembly 1Y, counterweights 7G and 7H are appropriately positioned near the second unit 4C and the second unit 4D, respectively. Here, in the tire assembly 1Y, the base plate 5, which carries one rectifier circuit 5A and two rectifier circuits 5B, is positioned adjacent to the second unit 4C; therefore, the masses of counterweights 7G and 7H are also set taking into account the masses of the base plate 5 and the rectifier circuits 5A and 5B. Rectifier circuit 5A is connected to generator 10A, and rectifier circuit 5B is connected to generator 10Y and generator 10Z, respectively.

[0137] According to the inventor's research, when multiple second units include at least one second power generation unit with an area of ​​S1 for both the first and second surfaces, and at least one second power generation unit with an area of ​​S2 for both the first and second surfaces, the VP characteristic of the tire assembly 1Y can also be made as follows: Figure 11 The VP characteristics shown.

[0138] According to the inventors' research, in order to ensure that the power generation of the second unit 4A reaches its peak in the speed range of 80 km / h and above, and that the power generation of the second unit 4B reaches its peak in the speed range of 60 km / h to 80 km / h, a speed of 1.5 is preferred. (S2 / S1) 16. Thus, by increasing the area, the power generation of the second unit 4B can be further increased. Furthermore, because the bending stiffness of the power generator 10Z is lower than that of the power generator 10Y, and the natural frequency of the second unit 4B is also lower than that of the second unit 4A, the speed range in which the power generation of the second unit 4B reaches its peak shifts towards the lower speed side. Therefore, in a larger speed range, the overall power generation of the tire assembly 1Y can be stabilized, improving the VP characteristics of the tire assembly 1Y. In addition, the inventors have confirmed that the area of ​​the first and second surfaces is not necessarily proportional to the power generation; when the area reaches 8000 mm²... 2 ~10000mm 2 At approximately [time value missing], the power generation reaches its limit. Furthermore, in Unit 2C and Unit 2D, the mass per unit area of ​​the counterweight components is the same.

[0139] <5. Features>

[0140] (1) According to the tire assembly 1 of the above embodiment, the first unit 3 and the second unit 4, which have different deformation mechanisms of the generator 10, can ensure the amount of electricity generated by the tire assembly 1 in a larger speed range. As a result, during the driving of the vehicle 8 on which the tire assembly 1 is installed, electricity can be stably supplied to the systems and devices connected to the first unit 3 and the second unit 4.

[0141] (2) In the tire assembly 1 according to the above embodiment, the first unit 3, the second unit 4, and the power control circuit 6 are distributed at N along the circumference of the tire 2 (wherein, N... 4). Furthermore, at least one of these elements is positioned off-center from the portion that is equally divided N times along the circumferential direction on the inner surface 200. This allows the first-order component of the RFV to be dispersed into an N-order component, and mitigates the N-order peak of the RFV, thereby suppressing vibration and noise generation caused by assembling the first unit 3, the second unit 4, and the power control circuit 6 onto the tire 2.

[0142] (3) In the tire assembly 1 according to the above embodiment, the mass difference between the first unit 3, the second unit 4, and the power control circuit 6, which are distributed at N, is reduced by the counterweights 7A and 7B. This suppresses the increase in the RFV of the tire assembly 1. Furthermore, by arranging the rectifier circuits 5A and 5B near the second unit 4, which has the smallest mass among the first unit 3, the second unit 4, and the power control circuit 6, the aforementioned mass difference can be further reduced. That is, the rectifier circuits 5A and 5B can function as counterweights, thus further suppressing the increase in the RFV of the tire assembly 1. Additionally, assuming that the rectifier circuits 5A and 5B are arranged near the first unit 3, more counterweights are needed to reduce the mass difference between the first unit 3 and the second unit 4, increasing the overall mass of the tire assembly 1. Therefore, arranging the rectifier circuits 5A and 5B near the relatively smaller second unit 4 also helps to suppress the increase in the overall mass of the tire assembly 1.

[0143] (4) According to the tire assembly 1 of the above embodiment, if the tire 2 is for passenger cars, the mass of each virtual mass point is set to 30g or less, and if the tire 2 is for large vehicles such as trucks / buses, the mass of each virtual mass point is set to 40g or less. As a result, the increase of RFV of the tire assembly 1 can also be suppressed.

[0144] (5) In the tire assembly 1 of the above embodiment, the pressing member 30 is mainly made of a composite material of rubber and carbon fiber. As a result, tensile strength that is not inferior to that when the pressing member 30 is mainly made of rubber can be maintained, and the weight is reduced.

[0145] (6) In the tire assemblies 1W to 1Y of the above embodiments, compared with tire assembly 1, more stable power generation can be achieved in the speed range (e.g., 50 km / h to 80 km / h) around 60 km / h where power generation is prone to decrease. In addition, tire assemblies 1W to 1Y are the same as tire assembly 1 and can achieve the effects described in (1) to (5).

[0146] <6. Variations>

[0147] The present invention has been described above as one embodiment, but the present invention is not limited to the above embodiment, and various modifications can be made without departing from its spirit. For example, the following modifications can be made. In addition, the spirit of the following variations can be appropriately combined.

[0148] (1) The number of the first unit 3 and the second unit 4 is not limited to the above embodiment and can be appropriately changed. That is, the tire assembly 1 only needs to have at least one first unit 3 and one second unit 4. For example, it can also be as follows: Figure 13 As shown in the tire assembly 1A, multiple first units 3 and multiple second units 4 are arranged along the width direction of the inner surface 200 (parallel to the central axis A1). Alternatively, the first units 3 and the second units can also be arranged at the same circumferential position on the inner surface 200. Furthermore, the tire assembly 1W only needs to have multiple first units, and the multiple first power generation units include: at least one first power generation unit having a counterweight member with mass M1 disposed between the power generation unit and the pressing member; and at least one first power generation unit having a counterweight member with mass M2 disposed between the power generation unit and the pressing member, where M1 > M2. The tire assembly 1X only needs to have multiple second power generation units, and the multiple second power generation units include: at least one second power generation unit having a counterweight member with mass M3; and at least one second power generation unit having a counterweight member with mass M4, where M3 < M4. The tire assembly 1Y only needs to have a plurality of second power generation units, wherein the plurality of second power generation units include: at least one second power generation unit with an area of ​​S1 on the first surface and the second surface; and at least one second power generation unit with an area of ​​S2 on the first surface and the second surface, and S1 < S2.

[0149] (2) The structures of rectifier circuits 5A and 5B, and power control circuit 6 are not limited to the embodiments described above. For example, at least one of rectifier circuits 5A and 5B may be mounted on the same substrate as power control circuit 6. Furthermore, power control circuit 6 may be composed of multiple substrates divided according to function (function of controlling the on / off state of the device, function of controlling the current supply, and energy storage function). Multiple substrates may constitute one virtual point, or may be configured to constitute two or more virtual points. In addition, the devices included in system 9 may be independently disposed on inner surface 200 along with rectifier circuits 5A and 5B, and power control circuit 6. That is, rectifier circuits 5A and 5B, power control circuit 6, and devices included in system 9 can be installed in any structure. Furthermore, the elements constituting one virtual point can be appropriately combined.

[0150] (3) The first electrode 112 can also be constructed by weaving conductive fibers into a fabric. The fibers can be, for example, flexible Cu wire or stainless steel wire. In addition, the first surface 110 can be formed by covering the outer periphery of the fibers with a first insulating film 111. Similarly, the second electrode 122 can also be constructed by weaving conductive fibers into a fabric, and the second surface 120 can be formed by covering the outer periphery of the fibers with a second insulating film 121. The fibers can be, for example, flexible Cu wire or stainless steel wire.

[0151] (4) In the first unit 3 and the second unit 4 of the above embodiments, counterweight component 31 and counterweight component 41 are respectively arranged on the outer side of belt 32 and belt 42, but counterweight component 31 and counterweight component 41 can also be arranged on the inner side of belt 32 and belt 42, respectively. In addition, belt 32 and belt 42 can be replaced with other components such as bag-shaped components. The same applies to the first unit 3A, the first unit 3B, and the second units 4A to 4D of the above embodiments.

[0152] (5) The control device 80 may not be a computer built into or installed in the vehicle 8. The control device 80 may be a portable information processing terminal such as a smartphone, tablet computer, or laptop PC.

[0153] (6) Unit 1 3, Unit 2 4, rectifier circuit 5A and rectifier circuit 5B, and power control circuit 6 can be distributed at 2 to 3 locations along the circumference of tire 2, or at 5 locations, or at 7 or more locations. Alternatively, rectifier circuit 5A and rectifier circuit 5B, and power control circuit 6 can be appropriately omitted. The same applies to tire assemblies 1W to 1Y.

[0154] (7) The counterweight component 31 of Unit 1 3 can also be omitted.

[0155] (8) In the above embodiments, in the second unit 4C and the second unit 4D, the mass per unit area of ​​the counterweight component is the same, but the mass per unit area of ​​the counterweight component can also be different. That is, in the second unit 4C and the second unit 4D, in addition to making the areas of the first surface and the second surface different, the VP characteristics of the tire assembly 1Y can also be adjusted by making the mass per unit area of ​​the counterweight component different.

[0156] Example

[0157] The following shows the experiments conducted by the inventors and their results. However, the present invention is not limited thereto.

[0158] <Experiment 1>

[0159] As described in the first embodiment above, a tire assembly 1B (e.g., embodiment) is prepared, comprising two first units, one second unit, a rectifier circuit, and a power control circuit. An air pressure sensor, which operates by receiving power from the first and second units, is connected to the power control circuit. The air pressure sensor is configured to connect wirelessly to an external device 93 (a general-purpose computer) when its power is on. Furthermore, a tire assembly 1C (comparative example) is prepared, having the same structure as tire assembly 1B except that it lacks a second unit. These tire assemblies 1B and 1C are mounted on the same rim 71, and each is given the same air pressure. The tire assemblies 1B and 1C with rim 71 are respectively mounted on... Figure 14 The experimental setup shown uses a rotating shaft 92 to rotate tire assemblies 1B and 1C on a rotating drum 91 at speeds equivalent to 20 km / h to 80 km / h, with the same wheel load applied. During the rotation of tire assemblies 1B and 1C, an external device 93 is used to check whether the air pressure sensors of each tire assembly 1B and 1C are activated and operating (i.e., whether there is wireless communication from the air pressure sensors). The time interval for the air pressure sensors to communicate wirelessly is also measured. This time interval corresponds to the time interval until a certain amount of power is accumulated in the power control circuit.

[0160] <Result 1>

[0161] In tire assembly 1B, the time until the air pressure sensor is confirmed to activate is similar in speed ranges of 60 km / h to 80 km / h to 20 km / h to 60 km / h. Subsequently, in tire assembly 1B, the air pressure sensor was confirmed to operate stably throughout the speed range of 20 km / h to 80 km / h. On the other hand, in tire assembly 1C, it was confirmed that the air pressure sensor activation and operation were not problematic in the low-speed range, but the time until activation of the air pressure sensor was confirmed increased as the speed approached 60 km / h. Furthermore, activation of the air pressure sensor in speed ranges above 60 km / h was not confirmed within the expected timeframe. Therefore, it was confirmed that the tire assembly of the above embodiment can generate electricity over a wider speed range.

[0162] <Experiment 2>

[0163] Prepare a tire assembly by fixing the first unit of the above embodiment to the inner surface of the tire, and use it as a reference tire assembly. Assemble this reference tire assembly onto the tire as follows: Figure 14 The experimental setup shown was rotated under specified air pressure and wheel load conditions, confirming that the power generation of the first unit peaked at a speed of 30 km / h. This first unit comprises a square generator with one side length of 35 mm, a counterweight component with a mass of 2.7 g, and a pressing component. Next, tire assemblies with identical generator, pressing component, and tire structures were prepared, with the counterweight components having masses set to 1 / 3 (0.9 g) and 1 / 4 (0.675 g) of the reference tire assembly, respectively, as well as a tire assembly omitting the counterweight component. Each tire assembly was assembled into the experimental setup described above, and each tire assembly was rotated at speeds from 20 km / h to 100 km / h under the same conditions as the reference tire assembly, measuring the power generation of the first unit of each tire assembly.

[0164] <Result 2>

[0165] The power generation curve of the first unit of each tire assembly is shown in the figure below. Figure 15 As shown. From Figure 15 The graphs show that in tire assemblies where the mass of the counterweight is set to 1 / 3 of the mass of the reference tire assembly, a peak in power generation is observed near 60 km / h; in tire assemblies where the mass of the counterweight is set to 1 / 4 of the mass of the reference tire assembly, a peak in power generation is observed near 50 km / h. This confirms that when the mass of the counterweight is set to less than 1 / 3 of the mass of the counterweight relative to the reference tire assembly, the peak power generation of the first unit shifts towards the high-speed side (50 km / h to 60 km / h). Furthermore, it was confirmed that in these tire assemblies, the power generation near 60 km / h exceeds that of the reference tire assembly. In tire assemblies omitting the counterweight, the overall power generation decreases compared to the reference tire assembly, and the shift of the peak power generation towards the high-speed side is not confirmed. This is attributed to the reduced bending stiffness of the first unit due to the absence of the counterweight, leading to a decrease in the natural frequency. Furthermore, it is believed that since there is no counterweight component, the deformation of the pressing component is difficult to be transmitted to the power generator through the counterweight component, thus reducing the power generation.

[0166] <Experiment 3>

[0167] Prepare a tire assembly by fixing the second unit of the above embodiment to the inner surface of the tire, and use it as a reference tire assembly. Assemble this reference tire assembly onto a tire as follows: Figure 14The experimental setup shown was rotated under specified air pressure and wheel load conditions, confirming that the power generation of the second unit peaked at speeds above 100 km / h. This second unit comprises a square generator with one side length of 25 mm, a counterweight component with a mass of 1.4 g, and a belt. Next, tire assemblies with identical tire and belt structures were prepared, with one side length of the generator set to 35 mm and the counterweight component to a mass of 2.7 g, and another tire assembly with one side length of the generator set to 25 mm and the counterweight component to a mass of 6.4 g. In each tire assembly, the counterweight component has the same square shape as the generator, and one side of it is the same length as the generator. That is, the mass per unit area of ​​the counterweight component is the same in all tire assemblies. Each tire assembly was assembled into the experimental setup described above, and each tire assembly was rotated at speeds from 20 km / h to 100 km / h under the same conditions as the reference tire assembly, and the power generation of the second unit of each tire assembly was measured.

[0168] <Result 3>

[0169] The power generation curve of the second unit of each tire assembly is shown in the figure below. Figure 16 As shown. From Figure 16 The graphs show that in both the tire assembly with a counterweight of 2.7g and the tire assembly with a counterweight of 6.4g, the overall power generation exceeds that of the benchmark tire assembly. Furthermore, in the tire assembly with a counterweight of 2.7g, in speed regions lower than the speed region where power generation reaches its peak, the slope of power generation relative to speed is greater than that of the benchmark tire in the same speed region. This confirms that in the tire assembly with a counterweight of 2.7g, the peak power generation shifts further into the lower speed region compared to the benchmark tire assembly. Additionally, in the tire assembly with a counterweight of 6.4g, the aforementioned slope is greater in the even lower speed region than that of the tire assembly with a counterweight of 2.7g. This confirms that in the tire assembly with a counterweight of 6.4g, the peak power generation shifts further into the lower speed region.

[0170] Label Explanation

[0171] 1. 1A~1C, 1W~1Y: Tire assembly; 2: Tire; 3. 3A, 3B: First power generation unit; 4. 4A, 4B, 4C, 4D: Second power generation unit; 8: Vehicle; 9: Vehicle system; 10. 10A, 10B, 10W, 10X, 10Y, 10Z: Power generation unit; 31: Pressing component.

Claims

1. A tire assembly comprising: Tires, which are installed on vehicles; One or more first power generation units; and One or more second power generation units, which are different from the first power generation unit. The first power generation unit has: A power generator, disposed on the inner surface of the tire; and A pressing member is fixed to the inner surface of the tire on both sides of the generator in a manner that spans the generator along the circumference of the tire, and the pressing member is deformable according to the deformation of the tire. The second power generation unit has: A generator, which is fixed to the inner surface of the tire; and A counterweight component overlaps the power generator from the side opposite to the inner surface, separated by the power generator. The power generator has: A first component, having a first insulating film forming a first surface; and The second component has a second insulating film forming a second surface, which is opposite to and in contact with the first surface. The first component and the second component are configured such that the actual contact area between the first surface and the second surface changes according to the force applied to the first component and the second component. The first insulating film and the second insulating film are configured such that one of them becomes positively charged and the other becomes negatively charged due to a change in the actual contact area.

2. The tire assembly according to claim 1, wherein, The tire assembly has multiple of the first power generation units. The plurality of the first power generation units include: At least one first power generation unit having a counterweight component of mass M1 disposed between the power generation unit and the pressing component; and At least one first power generation unit having a counterweight component of mass M2 disposed between the power generation unit and the pressing component, M1 > M2.

3. The tire assembly according to claim 1 or 2, wherein, The tire assembly has multiple of the second power generation units. The plurality of said second power generation units include: At least one second power generation unit having a counterweight component of mass M3; and At least one second power generation unit having a counterweight component with a mass of M4. M3 < M4.

4. The tire assembly according to claim 1 or 2, wherein, The tire assembly has multiple of the second power generation units. The plurality of said second power generation units include: The area of ​​the first and second surfaces is S1 for at least one second power generation unit; and At least one second power generation unit with an area of ​​S2 for the first and second surfaces. S1 < S2.

5. The tire assembly according to claim 1, wherein, The tire assembly also has one or more circuits that receive power from the first power generation unit and the second power generation unit respectively, and are connected to an external computer in a manner that enables data communication.

6. The tire assembly according to claim 5, wherein, The first power generation unit, the second power generation unit, and the circuit are distributed in four or more locations along the circumference of the tire.

7. The tire assembly according to claim 5, wherein, The first power generation unit, the second power generation unit, and the circuit are distributed at six or fewer locations along the circumference of the tire.

8. The tire assembly according to claim 6 or 7, wherein, The tire assembly also has a counterweight that reduces the mass difference between the dispersedly arranged first power generation unit, the second power generation unit, and the circuit.

9. The tire assembly according to claim 6 or 7, wherein, At least one of the first power generation unit, the second power generation unit, and the circuit is positioned off-center from the portion of the tire that is equally divided N times along the circumference.

10. The tire assembly according to claim 1 or 2, wherein, The pressing component comprises at least one of rubber, thermoplastic elastomer, thermoplastic resin, and thermosetting resin.

11. The tire assembly according to claim 10, wherein, The pressing component comprises a composite material of rubber and carbon fiber.

12. The tire assembly according to claim 5, wherein, The computer is configured to monitor at least one of the tire's air pressure, the tire's internal temperature, and the tire's rotational speed.

13. A method for manufacturing a tire assembly, the tire assembly comprising: Tires, which are mounted on vehicles; and Electric generator, The power generator has the following characteristics: A first component, having a first insulating film forming a first surface; and The second component has a second insulating film forming a second surface, which is opposite to and in contact with the first surface. The first component and the second component are configured such that the actual contact area between the first surface and the second surface changes according to the force applied to the first component and the second component. The first insulating film and the second insulating film are configured such that one becomes positively charged and the other becomes negatively charged due to a change in the actual contact area. in, The method for manufacturing this tire assembly includes the following steps: Prepare the tires; Prepare at least three power generating units, including a first power generating unit, a second power generating unit, and a third power generating unit; and The at least three generators are respectively disposed on the inner surface of the tire. The step of distributing the at least three generators on the inner surface of the tire includes the following steps: A pressing member capable of deforming according to the deformation of the tire is fixed to the inner surface of the first power generator on both sides of the first power generator in such a way that it spans the first power generator along the circumference of the tire, and a first counterweight member having a first mass is arranged between the first power generator and the pressing member so that the power generation of the first power generator reaches its peak in the first speed region of the rotational speed of the tire. A second counterweight component having a second mass is overlapped with the generator from the side opposite to the inner surface, separated by the generator, so that the power generation of the second generator reaches its peak in the second speed region of the tire's rotational speed; and The other pressing components are fixed to the inner surface of the tire on both sides of the third power generator in a manner that spans the third power generator along its circumference. A third counterweight component with a third mass smaller than the first mass is disposed between the third power generator and the other pressing components, so that the power generation of the third power generator reaches its peak in the third speed region of the tire's rotational speed. Alternatively, a fourth counterweight component with a fourth mass larger than the second mass overlaps with the third power generator from the side opposite to the inner surface, separated from the third power generator, so that the power generation of the third power generator reaches its peak in the third speed region of the tire's rotational speed. The first speed region is a region where the speed is lower than that of the third speed region, and the third speed region is a region where the speed is lower than that of the second speed region.

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