阅读说明：本技术 泵装置 (Pump device ) 是由 田中伸拓 于 2019-02-14 设计创作，主要内容包括：泵装置具备：第1压电泵；第2压电泵,其与第1压电泵的上游侧串联连接；驱动部,其对第1压电泵和第2压电泵供给交流的输入电力；以及分配设定部,其对分别供给于第1压电泵和第2压电泵的来自驱动部的输入电力的分配比例进行设定,分配设定部将向第2压电泵输入的输入电力相对于向第1压电泵输入的输入电力之比例设定为大于1且1.57以下。(The pump device is provided with: 1 st piezoelectric pump; a 2 nd piezoelectric pump connected in series with an upstream side of the 1 st piezoelectric pump; a drive unit that supplies alternating-current input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and a distribution setting unit that sets distribution ratios of input power from the drive unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively, wherein the distribution setting unit sets a ratio of input power to be input to the 2 nd piezoelectric pump to input power to be input to the 1 st piezoelectric pump to be greater than 1 and 1.57 or less.)

1. A pump device is characterized by comprising:

1 st piezoelectric pump;

a 2 nd piezoelectric pump connected in series with an upstream side of the 1 st piezoelectric pump;

a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and

a distribution setting unit that sets distribution ratios of the input power from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively,

the distribution setting unit sets a ratio of input power to the 2 nd piezoelectric pump to input power to the 1 st piezoelectric pump to be greater than 1 and 1.57 or less.

2. Pump apparatus according to claim 1,

the rated output of the 1 st piezoelectric pump and the rated output of the 2 nd piezoelectric pump are the same.

3. Pump arrangement according to claim 1 or 2,

the distribution setting unit sets a ratio of input power to the 2 nd piezoelectric pump to input power to the 1 st piezoelectric pump to be 1.1 to 1.38.

4. A pump device is characterized by comprising:

1 st piezoelectric pump;

a 2 nd piezoelectric pump connected in series with an upstream side of the 1 st piezoelectric pump;

a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and

a distribution setting unit that sets distribution ratios of input current values from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively,

the distribution setting unit sets a ratio of an input current value to be input to the 2 nd piezoelectric pump to an input current value to be input to the 1 st piezoelectric pump to be greater than 1 and 1.25 or less.

5. The pump arrangement according to claim 4,

the distribution setting unit sets a ratio of an input current value to be input to the 2 nd piezoelectric pump to an input current value to be input to the 1 st piezoelectric pump to be 1.05 to 1.17.

Technical Field

The present invention relates to a pump device.

Background

Conventionally, a pump device for transporting a fluid such as air has been disclosed (for example, see patent document 1).

The pump device of patent document 1 is a pump device in which a plurality of piezoelectric pumps are connected in series. The pump device drives each piezoelectric pump by applying a phase difference to input power of adjacent piezoelectric pumps among the plurality of piezoelectric pumps. This alleviates pressure pulsation when a plurality of piezoelectric pumps are connected in series.

The piezoelectric pump used in the pump device of patent document 1 has a structure in which a piezoelectric element and a metal plate are bonded to each other, and supplies ac power to these members to generate buckling deformation in a single-layer wafer mode, thereby transporting air.

Patent document 1 Japanese laid-open patent publication No. 2004-16906

The piezoelectric pump is a device that causes a piezoelectric element and a metal plate to bend and deform at a high speed, and has a higher temperature increase rate than other types of pumps. If the temperature of the pump becomes high and exceeds the heat-resistant temperature of the pump, the pump may malfunction, and as a result, the reliability of the pump device may be reduced.

In particular, when the piezoelectric pumps are connected in series, the high-temperature air heated by the upstream piezoelectric pump is supplied to the downstream piezoelectric pump, and therefore the temperature of the downstream piezoelectric pump tends to increase. Therefore, when the piezoelectric pumps are connected in series, the temperature of the pump on the downstream side becomes high and exceeds the heat-resistant temperature of the pump, and the pump may be likely to malfunction, which may result in a decrease in reliability of the pump device.

Disclosure of Invention

Accordingly, an object of the present invention is to solve the above-described problems and to provide a pump device with improved reliability.

In order to achieve the above object, a pump device according to the present invention includes: 1 st piezoelectric pump; a 2 nd piezoelectric pump connected in series to an upstream side of the 1 st piezoelectric pump; a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and a distribution setting unit that sets distribution ratios of the input power from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively, wherein the distribution setting unit sets a ratio of the input power to the 2 nd piezoelectric pump to the input power to the 1 st piezoelectric pump to be greater than 1 and 1.57 or less.

Further, the pump device of the present invention includes: 1 st piezoelectric pump; a 2 nd piezoelectric pump connected in series to an upstream side of the 1 st piezoelectric pump; a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and a distribution setting unit that sets distribution ratios of input current values from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively, wherein the distribution setting unit sets a ratio of an input current value to be input to the 2 nd piezoelectric pump to an input current value to be input to the 1 st piezoelectric pump to be greater than 1 and 1.25 or less.

According to the pump device of the present invention, the piezoelectric pumps connected in series are prevented from excessively increasing in temperature, and the reliability is improved.

Drawings

Fig. 1 is a schematic configuration diagram of a pump device.

FIG. 2 is a graph showing conditions and results of example 1 using the pump device of FIG. 1.

Fig. 3 is a graph showing the relationship between the power ratio and the pump temperature in example 1.

Fig. 4A is a diagram showing a relationship between pressure and flow rate of the piezoelectric pump of example 1 (conventional example).

Fig. 4B is a diagram showing a relationship between the pressure and the flow rate of the piezoelectric pump of example 1 (comparative example).

Fig. 5A is a diagram showing a relationship between pressure and flow rate of the piezoelectric pump of example 1 (example).

Fig. 5B is a diagram showing a relationship between pressure and flow rate of the piezoelectric pump of example 1 (example).

Fig. 5C is a diagram showing a relationship between pressure and flow rate of the piezoelectric pump of example 1 (example).

Fig. 5D is a diagram showing a relationship between the pressure and the flow rate of the piezoelectric pump of example 1 (example).

Fig. 6 is a diagram showing a relationship between pressure and flow rate of the piezoelectric pump of example 1 (comparative example).

Detailed Description

According to the 1 st aspect of the present invention, there is provided a pump device comprising: 1 st piezoelectric pump; a 2 nd piezoelectric pump connected in series to an upstream side of the 1 st piezoelectric pump; a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and a distribution setting unit that sets distribution ratios of the input power from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively, wherein the distribution setting unit sets a ratio of the input power to the 2 nd piezoelectric pump to the input power to the 1 st piezoelectric pump to be greater than 1 and 1.57 or less.

With this configuration, the temperature increase of the 1 st piezoelectric pump relative to the temperature increase of the 2 nd piezoelectric pump can be suppressed, and the 1 st piezoelectric pump and the 2 nd piezoelectric pump can generate heat in a balanced manner. This can suppress the risk of any one of the piezoelectric pumps becoming a high temperature equal to or higher than the heat-resistant temperature, and can suppress a failure of the piezoelectric pump, thereby improving the reliability of the pump device.

According to the 2 nd aspect of the present invention, there is provided the pump device according to the 1 st aspect, wherein the rated output of the 1 st piezoelectric pump and the rated output of the 2 nd piezoelectric pump are the same. According to such a configuration, by setting the input power as described above and causing the 1 st piezoelectric pump and the 2 nd piezoelectric pump to generate heat in a balanced manner, it is possible to further suppress the risk of either of the piezoelectric pumps becoming a high temperature equal to or higher than the heat-resistant temperature, and to further improve the reliability of the pump device.

According to a 3 rd aspect of the present invention, there is provided the pump device according to the 1 st or 2 nd aspect, wherein the distribution setting unit sets a ratio of input power to the 2 nd piezoelectric pump to input power to the 1 st piezoelectric pump to 1.1 or more and 1.38 or less. With this configuration, by uniformly generating heat in the 1 st piezoelectric pump and the 2 nd piezoelectric pump, the risk of any one of the piezoelectric pumps becoming a high temperature equal to or higher than the heat-resistant temperature can be further suppressed, and the reliability of the pump device can be further improved.

According to the 4 th aspect of the present invention, there is provided a pump device comprising: 1 st piezoelectric pump; a 2 nd piezoelectric pump connected in series to an upstream side of the 1 st piezoelectric pump; a drive unit configured to supply ac input power to the 1 st piezoelectric pump and the 2 nd piezoelectric pump; and a distribution setting unit that sets distribution ratios of input current values from the driving unit to be supplied to the 1 st piezoelectric pump and the 2 nd piezoelectric pump, respectively, wherein the distribution setting unit sets a ratio of an input current value to be input to the 2 nd piezoelectric pump to an input current value to be input to the 1 st piezoelectric pump to be greater than 1 and 1.25 or less. With this configuration, the temperature increase of the 1 st piezoelectric pump relative to the temperature increase of the 2 nd piezoelectric pump can be suppressed, and the 1 st piezoelectric pump and the 2 nd piezoelectric pump can generate heat in a balanced manner. This can further suppress the risk of any one of the piezoelectric pumps becoming a high temperature equal to or higher than the heat-resistant temperature, and can suppress the failure of the piezoelectric pump, thereby improving the reliability of the pump device.

According to a 5 th aspect of the present invention, there is provided the pump apparatus according to the 4 th aspect, wherein the distribution setting unit sets a ratio of an input current value to be input to the 2 nd piezoelectric pump to an input power to be input to the 1 st piezoelectric pump to be 1.05 or more and 1.17 or less. With this configuration, the 1 st piezoelectric pump and the 2 nd piezoelectric pump generate heat more uniformly, thereby further suppressing the risk of either of the piezoelectric pumps becoming a high temperature equal to or higher than the heat-resistant temperature, and further improving the reliability of the pump device.

(embodiment mode)

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

< integral Structure >

Fig. 1 is a schematic configuration diagram of a pump device 2 according to an embodiment.

The pump device 2 shown in fig. 1 includes a 1 st piezoelectric pump 4, a 2 nd piezoelectric pump 6, a drive unit 8, a control device 9, and a distribution setting unit 10. The suction object 12 is connected to the 2 nd piezoelectric pump 6.

The 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 are pumps connected in series with each other. The 1 st piezoelectric pump 4 is disposed on the downstream side, and the 2 nd piezoelectric pump 6 is disposed on the upstream side. No other pump is provided between the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6, and they are directly connected to each other.

The 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 of the present embodiment are both piezoelectric pumps using piezoelectric elements (may also be referred to as "micro blowers", "micro pumps", or the like). Specifically, the piezoelectric element (not shown) is bonded to a metal plate (not shown), and ac power is supplied to the piezoelectric element and the metal plate, so that buckling deformation in a single-layer wafer mode is generated and air is transported. Such a piezoelectric pump incorporates a diaphragm (not shown) having a valve function of restricting the flow of air in one direction.

In the present embodiment, the same standard piezoelectric pump is used as the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6. The 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 are manufactured by the same manufacturer, have the same product number, and have the same parameters such as the rated output (i.e., the flow rate per unit time) and the size. The confirmation of the product number, the rated output, and the like may be performed based on a catalog issued by the manufacturer or seller of the piezoelectric pump, or a product specification signed between the manufacturer or seller of the piezoelectric pump and a customer. Since the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 have the same specification, the same level of heat generation property (i.e., the same level of temperature increase rate per unit time) is obtained when the input power is the same.

The drive unit 8 is a battery that supplies input power to the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6. In the present embodiment, the driving unit 8 includes: a 1 st drive part 8A and a 2 nd drive part 8B. The 1 st drive unit 8A supplies input power to the 1 st piezoelectric pump 4, and the 2 nd drive unit 8B supplies input power to the 2 nd piezoelectric pump 6.

The drive unit 8 of the present embodiment supplies ac input power to the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6. The piezoelectric elements of the 1 st and 2 nd piezoelectric pumps 4 and 6 are driven by ac input power, and thereby undergo buckling deformation in the single-layer wafer mode.

The drive unit 8 is connected to a control device 9. The control device 9 is a member that controls the 1 st drive portion 8A and the 2 nd drive portion 8B, respectively. Specifically, the control device 9 controls electric power, voltage, current, and the like input from the drive unit 8 to the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6, respectively. The control device 9 is constituted by, for example, an mcu (micro Controller unit).

In the present embodiment, the assignment setting unit 10 is configured by the driving unit 8 and the control device 9. The assignment setting unit 10 includes: a function of setting the distribution ratio of the input power supplied from the driving unit 8 to each of the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6. The distribution setting unit 10 is not limited to the control device 9, and may set the input voltage by a resistor or may set the boosting ratio. Any type of distribution setting unit 10 may be used as long as it has a function of setting the distribution ratio of the input power.

The distribution setting unit 10 of the present embodiment may have a function of setting the distribution ratio of the "input current value". The input current value is a parameter substantially proportional to the deformation speed of the piezoelectric element of the piezoelectric pump. By adjusting the input current value, the deformation speed of the piezoelectric element can be adjusted, and the pump failure can be prevented.

The suction object 12 is an object to which air is sucked by the 2 nd piezoelectric pump 6 of the pump device 2. The object to be suctioned 12 is, for example, a breast pump, a snivel pump, or the like, but may be any other object to be suctioned. The fluid to be sucked is air, but may be any fluid other than air.

By sucking air from the suction object 12 by the pump device 2, negative pressure is generated inside the suction object 12. The pump device 2 having such a configuration functions as a so-called "negative pressure pump".

According to the configuration of the pump device 2 described above, the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 are supplied with input power from the 1 st driving unit 8A and the 2 nd driving unit 8B, respectively. The 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 are driven by the supply of input power, and the piezoelectric element generates buckling deformation at a high speed to transport air.

The 2 nd piezoelectric pump 6 sucks air from the suction object 12, pressurizes the sucked air inside, and supplies the air to the 1 st piezoelectric pump 4. The air pumped by the 1 st piezoelectric pump 4 is further pressurized inside the 1 st piezoelectric pump 4, and is discharged to the outside through the discharge port 4a.

In the above operation, the temperature rises while the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 pressurize the air inside. For example, when the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 are both driven by an input voltage of 1.9W, if the 2 nd piezoelectric pump 6 sucks air of, for example, 50 ℃ from the suction object 12, the sucked air is heated to, for example, about 60 ℃. The air is sucked into the 1 st piezoelectric pump 4, heated to, for example, about 70 degrees inside the 1 st piezoelectric pump 4, and then discharged from the discharge port 4a.

In this way, when air is supplied from the 2 nd piezoelectric pump 6 on the upstream side to the 1 st piezoelectric pump 4 on the downstream side, air heated by the 2 nd piezoelectric pump 6 is supplied to the 1 st piezoelectric pump 4. Therefore, the 1 st piezoelectric pump 4 tends to be higher in temperature than the 2 nd piezoelectric pump 6.

In contrast, in the present embodiment, the distribution ratio is set by the distribution setting unit 10 such that the input power to the 2 nd piezoelectric pump 6 is larger than the input power to the 1 st piezoelectric pump 4. By setting the distribution ratio of the input power to the 1 st piezoelectric pump 4 low in this manner, the temperature increase of the 1 st piezoelectric pump 4 with respect to the temperature increase of the 2 nd piezoelectric pump 6 is suppressed, and the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 can be caused to generate heat in a balanced manner. The balanced heat generation means that the maximum temperatures of the two pumps are balanced with each other to determine the heat generation amount of each pump. In particular, by suppressing an excessive temperature rise of the 1 st piezoelectric pump 4, it is possible to suppress failures such as adhesive separation between the bonding metals inside the pump and cracking of the piezoelectric element. Thus, the reliability of the pump device 2 can be improved.

In the case of a piezoelectric pump, the heat generation property is high as compared with other types of pumps, and a failure due to thermal damage is likely to occur. Therefore, the effect of suppressing the heat generation and hence the failure of the 1 st piezoelectric pump 4 by setting the input power as described above can be more effectively exhibited.

In the present embodiment, the rated output of the 1 st piezoelectric pump 4 is the same as that of the 2 nd piezoelectric pump 6. Therefore, the heat generation properties of the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 with respect to the input power are the same. In this case, the above-described setting of the input power can be performed more effectively, and the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 can generate heat in a balanced manner.

In the present embodiment, the allocation setting unit 10 is set such that the input current value to the 2 nd piezoelectric pump 6 is larger than the input current value to the 1 st piezoelectric pump 4. In the case of the piezoelectric pump, since the deformation speed of the piezoelectric element is substantially proportional to the current value of the input power, the deformation of the piezoelectric element of the 1 st piezoelectric pump 4 can be suppressed by setting the above-described distribution ratio of the input current value. Therefore, even when the heat-resistant temperature of the 1 st piezoelectric pump 4 increases or the temperature of the 1 st piezoelectric pump 4 increases, it is possible to effectively prevent a failure due to deformation of the piezoelectric element.

Even when the 1 st piezoelectric pump 4 and the 2 nd piezoelectric pump 6 have the same specification and the same rated output as in the present embodiment, there is a case where the actual output performance differs due to manufacturing errors. In this case, the 2 nd piezoelectric pump 6 may have a low output performance, and the 1 st piezoelectric pump 4 may have a high output performance. Thus, even if a large electric power is input to the 2 nd piezoelectric pump 6, a failure of the 2 nd piezoelectric pump 6 can be suppressed.

Next, example 1 of the embodiment will be explained.