JP7703508B2 - Piezoelectric power generation device and pump power generation system using pump pressure - Google Patents

Description

The present invention relates to a piezoelectric power generation device and a pump power generation system that utilizes pump pressure.

Carbon neutral measures are an urgent necessity to combat global warming, and there is also a demand in the field of industrial equipment for the creation of renewable energy and for products to become more efficient. Renewable energy has been attracting particular attention, and water turbine power generation, which uses water flow to rotate a blade, is common, but piezoelectric power generation, which uses water pressure, is also an example.

Patent Document 1 is a background technology in this technical field. Patent Document 1 discloses attaching a piezoelectric element to the impeller of a pump and extracting electricity from the pressure.

JP 2021-32080 A

In Patent Document 1, a piezoelectric element including a power generation unit is attached to the impeller of a pump to generate electricity, but because the impeller is a rotating body, the piezoelectric element may be detached from the impeller due to the water flow from various directions. As a result, the detachment of the piezoelectric element may lead to the pump locking or equipment failure at the destination of the water supply. In addition, the area in which the piezoelectric element can be attached to the impeller is limited, the amount of power generated is small, and in terms of pump performance, there is also the issue of performance degradation due to the attachment of foreign objects inside the impeller.

The present invention was made in consideration of the above problems, and aims to provide a piezoelectric power generation device and pump power generation system that uses pump pressure, eliminates the risk of pump locking, and can increase the amount of power generated.

One example of the present invention is a pump power generation system that generates electricity by pressure changes caused by pulsation of fluid discharged from a pump, and includes a pump, a first bypass pipe that branches the fluid from the pump's discharge port, a piezoelectric power generation device connected to the first bypass pipe, and a second bypass pipe that returns the fluid discharged from the piezoelectric power generation device to the pump's discharge port side. The piezoelectric power generation device is tank-shaped, and the space inside the tank is divided into a liquid layer and an air layer by an elastic body. The liquid layer has an inlet through which the fluid from the first bypass pipe flows in and an outlet through which the fluid flows out to the second bypass pipe. The air layer has a piezoelectric element, and electricity is generated by the air layer being compressed by pressure changes caused by the pulsation of the fluid flowing from the first bypass pipe applied to the liquid layer, and pressure is applied to the piezoelectric element.

The present invention provides a piezoelectric power generation device and pump power generation system that uses pump pressure, eliminates the risk of pump locking, and increases the amount of power generated.

1 is a configuration diagram of a pump power generation system according to a first embodiment. 1 is a cross-sectional view showing an internal structure of a piezoelectric power generating device according to a first embodiment. 2 is a cross-sectional view showing the internal structure of the piezoelectric power generation device in Example 1 with a piezoelectric element unit disposed on the upper surface. FIG. 1 is a cross-sectional view showing the internal structure of a piezoelectric generating device in Example 1, the tank of which is elongated horizontally. 1 is a cross-sectional view showing an internal structure of a piezoelectric generating device in Example 1, in which a fluid inlet is connected by a screw type. FIG. 11 is a configuration diagram of a pump power generation system according to a second embodiment. FIG. 11 is a configuration diagram of another pump power generation system in the second embodiment. FIG. 11 is a cross-sectional view of the structure of a pulsation generating device in accordance with a second embodiment. FIG. 11 is a cross-sectional view showing the shape of an impeller of a pulsation generating device in accordance with a second embodiment. FIG. 11 is a cross-sectional view showing another shape of the impeller of the pulsation generating device in the second embodiment. FIG. 11 is a structural view showing another shape of the impeller of the pulsation generating device in the second embodiment. FIG. 11 is a configuration diagram of a pump power generation system according to a third embodiment.

The following describes an embodiment of the present invention with reference to the drawings.

Figure 1 is a diagram of a pump power generation system that utilizes the pump pressure in this embodiment. In Figure 1, the pump power generation system 100 mainly consists of a pump 101 and a piezoelectric power generation device 104. The pump 101 has an intake port and an exhaust port, and sucks in a fluid from the intake port, boosts the pressure in a boosting path, and discharges it from the exhaust port. Then, the pressure change caused by the pulsation of the fluid discharged from the exhaust port of the pump 101 is converted into electricity by the piezoelectric power generation device 104 to generate electricity. In order not to affect the normal operation of the pump, the pump power generation system in this embodiment provides a bypass path for the power generation fluid separate from the normal operation, and incorporates a piezoelectric power generation device into the bypass path.

Specifically, in FIG. 1, a short pipe 102 is attached to the discharge port side of a pump 101, and a first bypass pipe 103 is provided to branch the fluid from the discharge port of the pump 101 to the short pipe 102. A piezoelectric power generation device 104 is then provided connected to the first bypass pipe 103, and a second bypass pipe 105 is provided to return the fluid discharged from the piezoelectric power generation device 104 to the secondary side (discharge port side) of the pump. This forms a flow of fluid to the piezoelectric power generation device 104. In FIG. 1, the flow of fluid is indicated by white arrows. Also, double lines are indicated between the short pipe 102 and the first bypass pipe 103, etc., but this indicates a pipe connection with a flange.

As shown in FIG. 1, a gate valve 106 may be provided on the primary side of the piezoelectric power generation device 104 to facilitate maintenance of the piezoelectric power generation device 104. A check valve 107 may be provided on the second bypass pipe 105 to prevent backflow. The fluid discharged from the piezoelectric power generation device 104 may be returned to the primary side (suction port side) of the pump instead of the secondary side.

In addition, in FIG. 1, a short pipe 102 is provided to connect the first bypass pipe 103, but instead of the short pipe 102, a gauge hole provided in the flange or casing of the pump may be used to connect the first bypass pipe 103 to the flange or casing of the pump.

Figure 2 is a cross-sectional view showing the internal structure of the piezoelectric power generation device in this embodiment. In Figure 2, the piezoelectric power generation device 104 is tank-shaped, and the space inside the tank is divided into a liquid layer 202 and an air layer 203 by an elastic body 204 such as rubber. Fluid flows into the liquid layer 202 through an inlet through which the fluid flows from the first bypass pipe 103 connected via a flange 207, and the fluid flows out to a second bypass pipe 105 connected to an outlet provided on the side of the tank (not shown). In addition, the air layer 203 is provided with a piezoelectric element unit 205 on the inner circumference of the tank, and is equipped with a power storage control device 206 that collects and stores the electricity generated by the piezoelectric element unit 205. The power storage control device 206 is connected to external equipment, etc., and enables the supply of electricity. In addition to the piezoelectric element, the piezoelectric element unit 205 is composed of a protective member such as rubber that protects the piezoelectric element, and a cover that blocks humidity.

The liquid layer 202 is pressurized by the fluid pressure of the pump, compressing the air layer 203, which then applies pressure to the piezoelectric element unit 205 to generate electricity. In other words, electricity is generated by utilizing the pressure difference from the pulsation of the fluid generated by the pump.

The piezoelectric element unit 205 may be attached anywhere within the air layer 203. For example, as shown in FIG. 3, the piezoelectric element unit 205 may be placed on the upper surface of the tank. The amount of power generated may be adjusted by increasing the size of the piezoelectric power generation device 104 or by increasing the number of tanks. For example, as shown in FIG. 4, the tank of the piezoelectric power generation device 104 may be elongated horizontally, and multiple piezoelectric element units 205 may be provided on the inner circumference of the tank. In FIG. 2 to FIG. 4, the inlet of the liquid layer 202 is connected via a flange 207, but as shown in FIG. 5, a screw 208 may be provided and the connection to the first bypass pipe 103 may be made by screwing.

In this way, in the present embodiment, in the piezoelectric power generation device 104, the liquid layer 202 and the air layer 203 are separated, and the piezoelectric element unit 205 is provided in the air layer 203, so that the fluid does not come into direct contact with the piezoelectric element unit 205, there is no possibility of the piezoelectric element being detached by the fluid, and there is no possibility that the detachment of the piezoelectric element will lead to the pump locking or equipment failure on the secondary side of the pump. In addition, the amount of power generation can be increased by adding more piezoelectric element units.

In addition, by simply installing a bypass path for the power-generating fluid and a piezoelectric power generation device in a conventional pump system, electricity is generated automatically when the pump is operated, which has the added benefit of reducing the hassle.

As described above, this embodiment can provide a piezoelectric power generation device and pump power generation system that uses pump pressure, can generate power using a piezoelectric element without the risk of the pump locking, and can increase the amount of power generated.

This embodiment describes a pump power generation system that uses the basic configuration of embodiment 1 and can further improve power generation efficiency.

Figure 6 is a diagram of the pump power generation system 200 in this embodiment. In Figure 6, the same components as those in Figure 1 are assigned the same reference numerals, and their description will be omitted. In Figure 6, the difference from Figure 1 is that a pulsation generator 301 is provided on the primary side of the piezoelectric power generation device 104 within the path of the first bypass pipe 103. The pulsation generator 301 intentionally generates pulsation in the fluid, thereby increasing the pressure fluctuation due to the pulsation of the fluid, and thus the pressure applied to the piezoelectric element in the piezoelectric power generation device 104 can be significantly changed, thereby increasing the power generation efficiency. Note that a double line is drawn between the pulsation generator 301 and the first bypass pipe 103, but this means that the pipe is connected with a flange. Note that the pipe connection of the pulsation generator 301 may be a screw-in type instead of a flange type.

In addition, by providing the pulsation generating device 301, the fluid output from the piezoelectric power generation device 104 generates large pulsations, and if it is returned to the secondary side of the pump via the second bypass pipe 105, this will have an effect on the secondary side. Therefore, it is desirable to reduce the pulsations by placing a flow clearing plate or the like on the secondary side of the piezoelectric power generation device 104, i.e., on the second bypass pipe 105, for example, between the piezoelectric power generation device 104 and the check valve 107.

In addition, in order to reduce the impact on the secondary side of the pump, the fluid discharged from the piezoelectric power generation device 104 may be returned to the primary side of the pump, although this will result in energy loss. Figure 7 is a configuration diagram of the pump power generation system 200 in this embodiment when the fluid discharged from the piezoelectric power generation device 104 is returned to the primary side of the pump. In Figure 7, even if the fluid output from the piezoelectric power generation device 104 is returned to the primary side of the pump via the second bypass pipe 105, the fluid output from the piezoelectric power generation device 104 will generate large pulsations due to the pulsation generating device 301, which may cause problems such as damage to the piping and vibration and noise. Therefore, it is desirable to reduce the pulsations by placing a clear flow plate or the like between the piezoelectric power generation device 104 and the check valve 107.

Figure 8 is a cross-sectional view of the structure of the pulsation generator in this embodiment. As shown in Figure 8, the pulsation generator 301 is composed of a body 401, an impeller 402, a main shaft 403, and a bearing 404, and is structured to rotate the impeller 402 by using the flow of fluid.

Figure 9 is a cross-sectional view showing the shape of the impeller 402 of the pulsation generator in Figure 8. Figure 9 shows a cross-sectional view of the impeller 402 in a plane perpendicular to the main shaft 403. As shown in Figure 9, the impeller 402 is composed of a single blade 501, which generates pressure fluctuations (pulsations) by rotating. This changes the pressure applied to the piezoelectric element, thereby increasing the power generation efficiency. Note that while Figure 9 shows a single-blade configuration, as long as pressure fluctuations (pulsations) are generated, a configuration of multiple blades arranged asymmetrically in the direction of rotation is also acceptable.

Figure 10 is a cross-sectional view showing another shape of the impeller in Figure 8. In Figure 10, the impeller 402 has multiple blades, and has non-uniformly spaced blades 502 with non-uniform blade spacing, which generates pressure fluctuations (pulsation) when rotated. Also, Figure 11 is a cross-sectional view showing yet another shape of the impeller in Figure 8. In Figure 11, the impeller 402 has multiple blades, and has non-uniform outer diameter blades 503 with non-uniform outer diameters, which generates pressure fluctuations (pulsation) when rotated.

In this embodiment, a structure that rotates an impeller has been described as a pulsation generating device, but this is not limited to this and any structure that generates pulsation in the fluid may be used.

As described above, this embodiment provides a pump power generation system that can improve power generation efficiency in addition to the effects of the first embodiment.

This example describes a small-scale power generation system based on Example 1, which is designed for small-scale, simple power generation.

Figure 12 is a configuration diagram of the pump power generation system in this embodiment. In Figure 12, the pump power generation system 300 mainly consists of a pump 600, a motor 700 that drives the pump 600, and a piezoelectric power generation device 800. Note that in Figure 12, only the pump 600 is shown in a cross-sectional view. In addition, a first bypass pipe 801 is provided to connect the piezoelectric power generation device 800 to a gauge hole provided in the pump flange 601 on the discharge side of the pump 600. In addition, a second bypass pipe 802 is provided to connect the piezoelectric power generation device 800 to a gauge hole provided in the pump flange 602 on the suction side of the pump 600. In addition, the piezoelectric power generation device 800 has the same configuration as the piezoelectric power generation device 104 described in the first embodiment and has the same structure as Figures 2 to 5. Note that the gauge holes on the discharge side and suction side of the pump 600 connected to the piezoelectric power generation device 800 may be gauge holes provided in the pump casing instead of the gauge holes provided in the pump flange.

In FIG. 12, the pump power generation system in this embodiment is provided with a first bypass pipe 801 and a second bypass pipe 802, which are bypass paths for the power generation fluid, separate from the normal operation of the pump, so as not to affect the normal operation of the pump. The fluid from the gauge hole provided on the discharge side of the pump 600 flows into the piezoelectric power generation device 800 through the first bypass pipe 801, and the fluid discharged from the piezoelectric power generation device 800 is returned to the gauge hole provided on the suction side of the pump 600 through the second bypass pipe 802. As a result, power generation can be made possible by simply attaching the piping (first bypass pipe 801, second bypass pipe 802) between the piezoelectric power generation device 800 and the pump 600, which is the bypass path for the power generation fluid, to a conventional pump system. Note that this embodiment is intended for small and simple power generation, so the amount of power generation is small, making it suitable for use as a power source for IoT (Internet of Things) products, etc.

As described above, this embodiment can provide a piezoelectric power generation device and a pump power generation system that utilizes pump pressure, which can reduce carbon emissions and prevent global warming, thereby contributing to achieving the SDGs (Sustainable Development Goals), particularly item 7, energy.

The present invention is not limited to the above-described embodiments, but includes various modified examples. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those having all of the configurations described. It is also possible to replace part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

100, 200, 300: Pump power generation system, 101, 600: Pump, 102: Short pipe, 103, 801: First bypass pipe, 104, 800: Piezoelectric power generation device, 105, 802: Second bypass pipe, 106: Gate valve, 107: Check valve, 202: Liquid layer, 203: Air layer, 204: Elastic body, 205: Piezoelectric element unit, 206: Power storage control device, 207: Flange, 208: Screw, 301: Pulsation generator, 401: Body, 402: Impeller, 403: Main shaft, 404: Bearing, 501: Single blade, 502: Unevenly spaced blade, 503: Uneven outer diameter blade, 601: Discharge side pump flange, 602: Inlet side pump flange, 700: Motor

Claims (15)

A pump power generation system that generates power by pressure changes caused by pulsations of a fluid discharged from a pump,
A pump that sucks a fluid through a suction port and discharges it through a discharge port;
a first bypass pipe for branching a fluid from a discharge port of the pump;
a piezoelectric power generating device connected to the first bypass pipe;
a second bypass pipe that returns the fluid discharged from the piezoelectric generating device to the discharge port side of the pump;
The piezoelectric power generation device has a tank shape, the space inside the tank is divided by an elastic body into a liquid layer and an air layer, the liquid layer has an inlet through which fluid from the first bypass pipe flows in and an outlet through which fluid flows out to the second bypass pipe, the air layer has a piezoelectric element, and the air layer is compressed due to pressure changes caused by pulsation of the fluid flowing in from the first bypass pipe and applied to the liquid layer, thereby applying pressure to the piezoelectric element, thereby generating electricity. The pump power generation system according to claim 1,
A pump power generation system, characterized in that a first bypass pipe branches off a fluid from a discharge port of the pump via a short pipe attached to the discharge port side of the pump. The pump power generation system according to claim 1,
A pump power generation system characterized in that a first bypass pipe is connected to a flange or a casing on the discharge port side of the pump, and branches fluid from the discharge port of the pump by utilizing a gauge hole provided in the flange or the casing on the discharge port side of the pump. The pump power generation system according to claim 1,
The pump power generation system according to claim 1, wherein the second bypass pipe returns fluid discharged from the piezoelectric power generation device to a suction port side of the pump. The pump power generation system according to claim 1,
A pump power generation system comprising a gate valve on the inlet side of the piezoelectric power generation device. The pump power generation system according to claim 1,
A pump power generation system comprising: a check valve provided in the second bypass pipe. The pump power generation system according to claim 1,
A pump power generation system comprising a pulsation generating device on the inlet side of the piezoelectric power generation device. The pump power generation system according to claim 7,
A pump power generation system comprising a flow straightening vane provided on the outlet side of the piezoelectric power generation device. The pump power generation system according to claim 7,
A pump power generation system, wherein the pulsation generating device has an impeller that is rotated by a fluid. The pump power generation system according to claim 9,
A pump power generation system, wherein the impeller is composed of one blade. The pump power generation system according to claim 9,
The impeller has a plurality of blades,
A pump power generation system, wherein the plurality of blades have non-uniform blade spacing or non-uniform blade outer diameters. A pump power generation system that generates power by pressure changes caused by pulsations of a fluid discharged from a pump,
A pump that sucks a fluid through a suction port and discharges it through a discharge port;
A motor that drives the pump;
a first bypass pipe connecting a flange or a gauge hole provided in a casing on the discharge port side of the pump;
a piezoelectric power generating device connected to the first bypass pipe;
a second bypass pipe that connects the fluid discharged from the piezoelectric power generation apparatus to a gauge hole provided in a flange or a casing on the suction port side of the pump;
The piezoelectric power generation device has a tank shape, the space inside the tank is divided by an elastic body into a liquid layer and an air layer, the liquid layer has an inlet through which fluid from the first bypass pipe flows in and an outlet through which fluid flows out to the second bypass pipe, the air layer has a piezoelectric element, and the air layer is compressed due to pressure changes caused by pulsation of the fluid flowing in from the first bypass pipe and applied to the liquid layer, thereby applying pressure to the piezoelectric element, thereby generating electricity. A piezoelectric power generation device that generates electricity by pressure changes caused by pulsation of a fluid discharged from a pump,
It is tank-shaped, and the space inside the tank is divided into a liquid layer and an air layer by an elastic body.
The liquid layer has an inlet through which the fluid discharged from the pump flows in and an outlet through which the fluid in the liquid layer flows out,
The air layer has a piezoelectric element,
A piezoelectric power generation device characterized in that the air layer is compressed due to pressure changes caused by pulsation of the fluid discharged from the pump that is applied to the liquid layer, and pressure is applied to the piezoelectric element, thereby generating power. The piezoelectric generating apparatus according to claim 13,
The piezoelectric power generation device is characterized in that the piezoelectric element is arranged on an inner periphery of a tank in the air space, and the air space is provided with a power storage control device that collects and stores the power generated by the piezoelectric element. The piezoelectric generating apparatus according to claim 13,
A piezoelectric generator characterized in that the inlet is provided with a flange or a screw, and is connected to a pipe into which the fluid discharged from the pump flows via the flange or the screw.

Images