Patent Description:
Currently, all kinds of products used in various fields, such as pharmaceutical industries, computer techniques, printing industries or energy industries, are developed in the trend of elaboration and miniaturization. Among these, products, such as mini pumps, micro atomizers, printheads or industrial printers, generally employ a fluid transportation device, and the micro pump used therein as a driving core is an essential component of the fluid transportation device. Therefore, how to break through the technical bottleneck by providing innovative structures of the micro pump and the fluid transportation device is the crucial issue of development. With the rapid advancement of science and technology, the applications of fluid transportation device are more and more diversified, for example, the fluid transportation device can be utilized in industrial applications, biomedical applications, healthcare, electronic cooling, even the most popular wearable devices and so on. As the result, the conventional fluid transportation devices gradually tend to miniaturize the structure and maximize the flow rate thereof.

However, although the trend for the development of the fluid transportation device is maximizing the flow rate thereof, the design of the structure for the fluid transportation device still has to consider some issues, such as heat dissipation, stability, endurance performance, and vibration suppression, of the micro pump itself during operation while maintaining a sufficient flow rate. The issues described above are even more important when the fluid transportation device is employed in the biomedical and healthcare applications since such issues mentioned above might significantly affect the using experience and the comfort level for the user.

Accordingly, take the electric breast pump, described in <CIT> and<CIT>, as an example of the application of the fluid transportation device in the healthcare field. The structure of current commercial electric breast pump generally includes a breast suctioning shield, a breast milk collection bottle, a guiding tube, a driving pump, a control circuit and a battery. The power for the overall device is provided by the battery for operation. The breast suctioning shield is used by attaching to the breast of the user while a driving signal is transmitted from the control circuit to the driving pump to produce a suctioning force, and the breast milk can be guided to the breast milk collection bottle via the guiding tube for storage, thereby achieving the purpose of assisting the user in collecting the breast milk thereof.

<CIT> describes a pump unit which includes a plurality of piezoelectric pumps, a flow path-defining member, and a heat-dissipating part. The plurality of piezoelectric pumps each include a first flow path for sucking and discharging of fluid. The flow path-defining member includes a second flow path for connection to the first flow paths in the plurality of piezoelectric pumps. Heat generated in the plurality of piezoelectric pumps is dissipated through the heat-dissipating part. The heat-dissipating part is disposed between the flow path-defining member and each of the plurality of piezoelectric pumps. The heat-dissipating part has through-holes through which the first flow paths are connected to the second flow path.

<CIT> relates to a fluid control device which comprises a piezoelectric pump, a valve, a cuff, a heat sink, and a control part. The valve comprises a first valve case provided with first vent holes and, and a second valve case provided with a second vent hole and a third vent hole. A manchette rubber tube of the cuff is fitted to the second vent hole of the valve, and the valve is thereby connected to the cuff. The piezoelectric pump comprises a pump case provided with discharge holes and. The first vent holes and of the valve are connected to the discharge holes and of the piezoelectric pump. The heat sink is fitted to a bottom surface of the pump case. The heat sink comprises an opposed part opposed to the third vent hole.

However, the discussion regarding to the configuration of the fluid transportation device itself, the formality of the fluid pump in fluid transportation device and how to install the fluid pump in the device adopting it are rare. Take the electric breast pump mentioned above as an example, if the efficacy in heat dissipation, stability, endurance performance, and vibration suppression during the operating of operation core, i.e. the fluid pump itself, is insufficient, the comfortability and spending time thereof may not fulfill the requirement of the user. All these issues above are highly related with the installation manner of the fluid pump utilized in the device. Accordingly, there still has a need to improve the performance of the fluid pump utilized in the current device, e.g. the electric breast pump and devices in other fields of industrial application like biomedical application, healthcare, and electronic cooling, to achieve the intended purpose thereof.

The object of the present disclosure is to improve the efficacy of the conventional fluid pump, such as heat dissipation, stability, endurance performance, and vibration suppression, as being installed in the device utilizing the fluid pump while ensuring a sufficient flow supply of the fluid simultaneously. Notably, the fluid pump module described in the present disclosure can be installed in all kinds of devices utilizing the fluid pump, e.g., electric breast pumps, liquid filters, fluid filters, fresh air fans, hair dryers, in various fields, such as the industrial application, the biomedical application, the healthcare, and the electronic cooling.

The above mentioned object is solved by a fluid pump module having the features of claim <NUM>. The fluid pump module includes a heat dissipation board assembly, a fixing frame body, fluid pumps, a control board and a conveying pipe. The fixing frame body is fixed at one side of the heat dissipation board assembly, so as to form two accommodating spaces between the heat dissipation board assembly and the fixing frame body. Two fluid pumps are disposed in the two accommodating spaces respectively. The control board is disposed at another side of the heat dissipation board assembly. The conveying pipe connects with the two fluid pumps so as to form a series connection therebetween. The control board controls the operation of the fluid pumps, and the heat dissipation board assembly dissipates heats produced by a module formed by the two fluid pumps. The heat dissipation board assembly comprises a plurality of heat dissipation flat boards and a heat dissipation lateral board, wherein ends at the same side of the plurality of heat dissipation flat boards are connected with the heat dissipation lateral board, so as to form the two accommodating spaces between the heat dissipation board assembly and the fixing frame body.

The above contents of the present disclosure will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:.

Please refer to <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. In order to solve the problems resides in the prior art, a fluid pump module <NUM> is provided in the present disclosure. In a preferred embodiment, the fluid pump module <NUM> includes a heat dissipation board assembly <NUM>, a control board <NUM>, a conveying pipe <NUM>, two fluid pumps <NUM> and a fixing frame body <NUM>. The heat dissipation board assembly <NUM> includes a plurality of heat dissipation flat boards <NUM> and a heat dissipation lateral board <NUM>. In this embodiment, one end of each of the two heat dissipation flat boards <NUM> are both connected with the heat dissipation lateral board <NUM> to form a "C" shape structure. The heat dissipation board assembly <NUM> is made of a material with good thermal conductivity, such as metal. The fixing frame body <NUM> is fixed at one side of the heat dissipation board assembly <NUM>, so as to form two accommodating spaces <NUM> between the heat dissipation board assembly <NUM> and the fixing frame body <NUM>. The two fluid pumps <NUM> are respectively disposed in the two accommodating spaces <NUM> in a mirror symmetrical arrangement. One of the heat dissipation flat boards <NUM> is sandwiched between the two fluid pumps <NUM> so as to form a sandwich structure. The control board <NUM> is disposed at another side of the heat dissipation board assembly <NUM>. The conveying pipe <NUM> connects and is in fluid communication with the two fluid pumps <NUM> so as to form a series connection therebetween. The control board <NUM> controls the operation of the two fluid pumps <NUM>, and the heat dissipation board assembly <NUM> dissipates heats produced by a module formed by the two fluid pumps <NUM>. In the present disclosure, the control board <NUM> may include, but not limited thereto, a processor, a memory, a temporary memory, a network communication module, a router, an I/O device, an operating system and/or an application program, which are electrically connected with each other through a known manner so as to perform the operation of calculation and storage, based on the practical requirements. The control board <NUM> transmits a driving signal for controlling the operation or the status of the fluid pump module <NUM> to a near remote end, so as to manage and coordinate the components of the fluid pump module <NUM>.

Please refer to FG. <NUM> and <FIG>. In the embodiment described above, each of the fluid pumps <NUM> has a flat cylindrical shape and includes a tubular disc <NUM>, a core module <NUM> and a cover <NUM> which are sequentially stacked from bottom to top. The flowing path of the fluid pump <NUM> is accommodated in the tubular disc <NUM> for the fluid to flow in and out. The core module <NUM> is the power source for driving a fluid flow and is driven by the driving signal from the control board <NUM>. The bottom surface of the cover <NUM> is combined with the top end of the tubular disc <NUM>, so as to seal the core module <NUM> in the fluid pump <NUM>. In one aspect of the present disclosure, since the fluid pump <NUM> has a flat cylindrical shape, when the two fluid pumps <NUM> are respectively disposed in the two accommodating spaces <NUM> in a mirror symmetrical arrangement to form a sandwich structure, in which one of the fluid pumps <NUM>, one of the heat dissipation flat boards <NUM> and the other of the fluid pumps <NUM> are sequentially stacked from top to bottom, the contact areas of the cover <NUM> and the tubular disc <NUM> with the heat dissipation board assembly <NUM> can be maximized. Therefore, the heat dissipation efficiency for the core module <NUM> in the fluid pump <NUM> can be optimized during operation, thereby avoiding the problem that the operation efficiency of the core module <NUM> is lowered due to the rising temperature derived from poor heat dissipation after the fluid pump <NUM> is operated for a period of time. Furthermore, in another aspect of the present disclosure, since the two fluid pumps <NUM> are arranged in a mirror symmetrical manner, when the two fluid pumps <NUM> are operating at the same time, the vibration peaks of one of the fluid pumps <NUM> can counteract the vibration valleys of the other of the fluid pumps <NUM>, so as to make the operation of the fluid pump module <NUM> more stable which not only elongates the life time of the fluid pump module <NUM>, but also reduces the power consumption of the fluid pumps <NUM> during operation. In addition, when the fluid pump module <NUM> of the present disclosure is adapted to the healthcare and biochemical devices (such as the electric breast pump mentioned above) or other devices with special requirements with smooth operation, the good heat dissipation capability and the stable operation performance of the present fluid pumps <NUM> can also provide the user a better using experience, thereby achieving the purpose of improving the configuration of the conventional fluid transportation device while ensuring the sufficient fluid flow supplement.

Please refer to <FIG> and <FIG>. The fixing frame body <NUM> includes a frame body flat board <NUM>, frame body side walls <NUM>, frame body openings <NUM> and frame body fixing elements <NUM>. The frame body flat board <NUM> is located at the top of the fixing frame body <NUM>. The frame body side walls <NUM> are perpendicularly disposed at two opposite ends of the frame body flat board <NUM>, and the frame body fixing elements <NUM> are disposed at ends of the frame body side walls <NUM> opposite to the frame body flat board <NUM>, so as to form a "Π" shape structure. In an embodiment, the fixing frame body <NUM> is fixed on the heat dissipation board assembly <NUM> through engaging the frame body side walls <NUM> in indentations <NUM> provided at two opposite ends of the upper layer of the heat dissipation board assembly <NUM> and fixing the frame body fixing elements <NUM> located at the ends of the frame body side walls <NUM> on the lower layer of the heat dissipation board assembly <NUM>, so as to form the accommodating spaces <NUM> for disposing the fluid pumps <NUM> therein. Moreover, the frame body openings <NUM> are respectively provided on the frame body side walls <NUM> for allowing the conveying pipe <NUM> to extend out and serially connect the two fluid pumps <NUM>. Notably, in the present disclosure, the optimal amount of the fluid pumps <NUM> is two, and accordingly, the fluid pump module <NUM> provides two accommodating spaces <NUM> in this embodiment. However, one skilled in the art would understand that the amount of the fluid pumps <NUM> may be increased in accordance with the practical demands, and for accommodating more fluid pumps <NUM>, the amount of the accommodating spaces <NUM> also may be increased through modifying the heat dissipation board assembly <NUM>, for example, increasing the number of the heat dissipation flat boards <NUM> to provide more accommodating spaces <NUM> and thus accommodate more fluid pumps <NUM>.

Please further refer to <FIG>. In an embodiment of the present disclosure, the tubular disc <NUM> includes an inflow tube <NUM>, an outflow tube <NUM> at the opposite side of the inflow tube <NUM>, and a protrusion portion <NUM> located between the inflow tube <NUM> and the outflow tube <NUM>. Within the region surrounding by the inflow tube <NUM>, the outflow tube <NUM> and the protrusion portion <NUM>, an inflow annular layer <NUM> is disposed. The inflow annular layer <NUM> includes a notch which is in communication with the outflow tube <NUM>, and a fluid inlet <NUM>, which is in communication with the inflow tube <NUM>, is located at a position above the inflow annular layer <NUM> opposite to the notch. Within the inflow annular layer <NUM>, an outflow annular layer <NUM> is disposed. The outflow annular layer <NUM> includes a fluid outlet <NUM> which is in communication with the notch of the inflow annular layer <NUM> and the outflow tube <NUM>. The protrusion portion <NUM> of the tubular disc <NUM> includes a plurality of positioning latches <NUM>. Moreover, the core module <NUM> includes a first electrode <NUM> and a second electrode <NUM>, wherein the first electrode <NUM> includes a first electrode positioning hole 1428A for engaging with one of the positioning latches <NUM> on the protrusion portion <NUM>, and the second electrode <NUM> includes a second electrode positioning hole 1429A for engaging with another positioning latch <NUM> on the protrusion portion <NUM>. Furthermore, the cover <NUM> includes a first cover protrusion <NUM> and a second cover protrusion <NUM>. The cover <NUM> is engaged and fixed with the tubular disc <NUM>, so as to dispose the core module <NUM> between the tubular disc <NUM> and the cover <NUM>, and the position of the first cover protrusion <NUM> is corresponding to the fluid inlet <NUM> and the position of the second cover protrusion <NUM> is corresponding to the protrusion portion <NUM>.

According to an embodiment of the present disclosure, in order to optimize the dimension of the fluid pump <NUM> and the flow rate of the fluid driven thereby, so as to drive a maximal amount of flow with a smaller volume the fluid pump module <NUM>, a total length of the fluid pump <NUM> without the inflow tube <NUM> and the outflow tube <NUM> is within a range of <NUM> ± <NUM>, a total width of the fluid pump <NUM> is within a range of <NUM> ± <NUM>, and a thickness of the fluid pump <NUM> is within a range of <NUM> ± <NUM>. Through the design of the dimension of the fluid pump <NUM>, an output pressure of the fluid pump <NUM> is within a range of <NUM> mmHg ± <NUM> mmHg, and an output flow rate of the fluid pump <NUM> is within a range of <NUM>/min ± <NUM>/min. In accordance with one aspect of the present disclosure, the total length, the total width and the total thickness of the fluid pump <NUM> and the lengths and diameters of the inflow tube <NUM> and the outflow tube <NUM> mentioned above are only illustrated as an example which can be modified based on the requirements of the device adopting the fluid pump <NUM> and are still within the scope of the present disclosure.

Accordingly, the length of any one of the inflow tube <NUM> and the outflow tube <NUM> of the fluid pump <NUM> is equal to or less than <NUM>, and the diameter of any one of the inflow tube <NUM> and the outflow tube <NUM> of the fluid pump <NUM> is equal to or less than <NUM>. Moreover, a hardness of the cover <NUM> of the fluid pump <NUM> is greater than 333MPa based on Brinell scale (according to the test standard in ISO2039-<NUM>). The material of the cover <NUM> is a heat conductive material or an aluminum alloy material. Notably, the hardness of the material of the cover <NUM> should be sufficient to resist the force caused by the vacuum formed during the fluid pump <NUM> is operating. If the hardness of the cover <NUM> is insufficient, the fluid pump <NUM> may collapse inwardly, thereby influencing the output efficacy of the fluid pump <NUM> and resulting in interferences and collisions between internal mechanisms of the fluid pump <NUM>. In addition, the material of the cover <NUM> can be a metal material (such as the aluminum alloy). The metal material which is the heat conductive material provides a thermal conduction effect, so that the overall heat dissipation capability of the fluid pump <NUM> can be enhanced. A better heat dissipation capability for the fluid pump <NUM> is helpful for maintaining the performance of the fluid pump <NUM> at a desired level.

According to another embodiment of the present disclosure, the length of any one of the inflow tube <NUM> and the outflow tube <NUM> of the fluid pump <NUM> is equal to or more than <NUM>, and the diameter of any one of the inflow tube <NUM> and the outflow tube <NUM> of the fluid pump <NUM> is equal to or more than <NUM>. Furthermore, the hardness of the cover <NUM> of the fluid pump <NUM> is greater than 333MPa based on Brinell scale (according to the test standard in ISO2039-<NUM>). The material of the cover <NUM> is a heat conductive material or an aluminum alloy material. Notably, the hardness of the material of the cover <NUM> should be sufficient to resist the force caused by the vacuum formed during the fluid pump <NUM> is operating. If the hardness of the cover <NUM> is insufficient, the fluid pump <NUM> may collapse inwardly, thereby influencing the output efficacy of the fluid pump <NUM> and resulting in interferences and collisions between internal mechanisms of the fluid pump <NUM>.

Please refer to <FIG> and <FIG>. According to an embodiment of the present disclosure, the core module <NUM> includes a first electrode <NUM> and a second electrode <NUM>. The first electrode <NUM> includes a first electrode positioning hole 1428A for engaging and fixing on one of the positioning latches <NUM> on the protrusion portion <NUM> of the tubular disc <NUM>. The second electrode <NUM> includes a second electrode positioning hole 1429A for engaging and fixing on another positioning latch <NUM> on the protrusion portion <NUM> of the tubular disc <NUM>. Notably, the protrusion portion <NUM> of the tubular disc <NUM> is made of PC (Polycarbonate) material which is regarded as insulation material, thereby the first electrode <NUM> and the second electrode <NUM> would not short circuit. Further, it is noted that the core module <NUM> can be a fluid pump <NUM> or a piezoelectric fluid pump, but not limited thereto. The core module <NUM> can be any kind of pump capable of conveying the fluid without departing from the scope of the present disclosure.

According to the present disclosure, the cover <NUM> includes a first cover protrusion <NUM> and a second cover protrusion <NUM>. The cover <NUM> is fixed and engaged with the tubular disc <NUM> so as to dispose the core module <NUM> between the tubular disc <NUM> and the cover <NUM>. The first cover protrusion <NUM> is correspondingly disposed at a position above the fluid inlet <NUM>, and the second cover protrusion <NUM> is disposed at a position corresponding to the protrusion portion <NUM>. Notably, after the first cover protrusion <NUM> seals with the tubular disc <NUM>, the fluid inlet <NUM> is formed between the first cover protrusion <NUM> of the cover <NUM> and the inflow annular layer <NUM>. More specifically, the fluid inlet <NUM> is located between the first cover protrusion <NUM> and the core module <NUM>, which is located above the inflow annular layer <NUM>, so that when the core module <NUM> is operating, the fluid is inhaled into the fluid pump <NUM> through the fluid inlet <NUM> via the inflow tube <NUM>, is conveyed from a space above the core module <NUM> to a space below the core module <NUM>, passes through the fluid outlet <NUM> and the notch of the inflow annular layer <NUM>, and then is exhaled out of the fluid pump <NUM> through the outflow tube <NUM>. Notably, although the second cover protrusion <NUM> of the cover <NUM> is sealed with the protrusion portion <NUM> of the tubular disc <NUM>, the second cover protrusion <NUM> does not contact with the first electrode <NUM> and/or the second electrode <NUM> of the core module <NUM>, thereby preventing from short circuits therebetween. Alternatively, a sealant or an insulating glue also can be applied between the first electrode <NUM> or the second electrode <NUM> and the second cover protrusion <NUM>, so as to avoid the first electrode <NUM> and/or the second electrode <NUM> from contacting with the second cover protrusion <NUM> and short circuits as the core module <NUM> is operating.

Please refer to <FIG> which is a schematic exploded view showing the core module of the present disclosure. In the embodiment, the core module <NUM> is encased by the cover <NUM> and the tubular disc <NUM> and driven by the control board <NUM> through a circuit loop formed by the first electrode <NUM> and the second electrode <NUM>. The core module <NUM> includes a piezoelectric sheet <NUM>, an inflow plate <NUM>, a frame <NUM>, a second plate element <NUM>, a first plate element <NUM>, a valve sheet <NUM> and an outflow plate <NUM> which are sequentially stacked from top to bottom. According to the present disclosure, the frame <NUM> is disposed on the second plate element <NUM>, the second plate element <NUM> is fixed on the first plate element <NUM>, the first plate element <NUM> includes first through holes 1425A disposed thereon, the second plate element <NUM> includes second through holes 1424A disposed thereon, and a thickness of the second plate element <NUM> is greater than a thickness of the first plate element <NUM>. A plurality of second through holes 1424A are provided on the second plate element <NUM> and a plurality of first through holes 1425A are provided on the first plate element <NUM>, and the amounts, positions, and diameters of the second through holes 1424A are corresponding to those of the first through holes 1425A. In this embodiment, the diameter of the second through holes 1424A and the diameter of the first through holes 1425A are identical. Further, the second plate element <NUM> also includes a connection point (not shown) for electrically connecting with a conductive wire. In one aspect of this embodiment, the second plate element <NUM> is a metal plate.

Please further refer to <FIG>. The inflow plate <NUM> includes a plurality of inflow apertures 1422A, and the inflow apertures 1422A are arranged in a shape on the plane of the inflow plate <NUM>. In an embodiment of the present disclosure, the inflow apertures 1422A are arranged in a circular shape. Through the arranged shape of the inflow apertures 1422A, an actuation region 1422B and a stationary region 1422C are respectively defined on the inflow plate <NUM>. The actuation region 1422B is enclosed by the inflow apertures 1422A and is driven by the deformation of the piezoelectric sheet <NUM> to move upwardly and downwardly. The stationary region 1422C is outside the inflow apertures 1422A and is used to maintain the position of the inflow plate <NUM> in the core module <NUM>. Each of the inflow apertures 1422A mentioned above has a tapered shape for enhancing the inflow efficiency which is easy for flowing-in and difficult for flowing-out, so as to prevent the backflow of the fluid. The amount of the inflow apertures 1422A is even. In one of the embodiments, the amount of the inflow apertures 1422A is <NUM>, and in another embodiment, the amount of the inflow apertures 1422A is <NUM>, but not limited thereto. Besides, the arranged shape of the inflow apertures 1422A can be different, such as a rectangular shape, a square shape, or a circular shape, but not limited thereto.

The piezoelectric sheet <NUM> mentioned above has a shape of circular. The piezoelectric sheet <NUM> is disposed on the actuation region 1422B of the inflow plate <NUM> and the shape thereof is corresponding to the actuation region 1422B. In this embodiment, the inflow apertures 1422A are arranged in a circular shape, so that the actuation region 1422B is defined as a circular shape, and the piezoelectric sheet <NUM> also has a circular shape. As described above, the arranged shape of the inflow apertures 1422A can be rectangle, square or circle. When the shape of the actuation region 1422B varies as the arranged shape of the inflow apertures 1422A changes, the shape of the piezoelectric sheet <NUM> should also be changed accordingly. In one embodiment of the present disclosure, the inflow apertures 1422A are arranged in a circular shape to match up with the piezoelectric sheet <NUM> having a circular shape, and accordingly, the appearance of the core module <NUM> is also set up in a circular shape.

According to the present disclosure, when the piezoelectric sheet <NUM> receives the driving signal (a driving voltage and a driving frequency), the electrical energy is converted into the mechanical energy through the converse piezoelectric effect, wherein a deformation level of the piezoelectric sheet <NUM> is controlled by the level of the driving voltage, and a deformation frequency of the piezoelectric sheet <NUM> is controlled by the driving frequency. The core module <NUM> is driven to convey the fluid through the deformation of the piezoelectric sheet <NUM>. When the actuation region 1422B of the inflow plate <NUM> bends upwardly, the valve sheet <NUM> is drawn upwardly to seal the first through holes 1425A of the first plate element <NUM>, and at this moment, the fluid is inhaled into the core module <NUM> through the inflow apertures 1422A. Then, when the piezoelectric sheet <NUM> deforms again upon receiving the driving signal, the actuation region 1422B of the inflow plate <NUM> is driven to bend downwardly, and the fluid in the core module <NUM> flows downwardly and passes through the second through holes 1424A of the second plate element <NUM> and the first through holes 1425A of the first plate element <NUM> at the same time. The valve sheet <NUM> is pushed and displaced through the motive energy of the downwardly flowed fluid, so that the valve sheet <NUM> departs from the first through holes 1425A and abuts against the outflow plate <NUM>, thereby opening a flowing path and exhaling the fluid through an outflow aperture 1427A. As a result, in the core module <NUM>, the fluid pump <NUM> can achieve the effect of driving a large amount of fluid flow through driving the inflow plate <NUM> to bend in a reciprocating manner by the piezoelectric sheet <NUM>.

Claim 1:
A fluid pump module (<NUM>), comprising:
a heat dissipation board assembly (<NUM>);
a fixing frame body (<NUM>) fixed at one side of the heat dissipation board assembly (<NUM>), so as to form two accommodating spaces (<NUM>) between the heat dissipation board assembly (<NUM>) and the fixing frame body (<NUM>);
two fluid pumps (<NUM>) respectively disposed in the two accommodating spaces (<NUM>);
wherein the heat dissipation board assembly (<NUM>) dissipates heats produced by a module formed by the two fluid pumps (<NUM>),
characterized by:
a control board (<NUM>) disposed at another side of the heat dissipation board assembly (<NUM>); and
a conveying pipe (<NUM>) connected between the two fluid pumps (<NUM>) so as to connect the two fluid pumps (<NUM>) in series,
wherein the control board (<NUM>) controls operations of the two fluid pumps (<NUM>),
wherein the heat dissipation board assembly (<NUM>) comprises a plurality of heat dissipation flat boards (<NUM>) and a heat dissipation lateral board (<NUM>),
wherein ends at the same side of the plurality of heat dissipation flat boards (<NUM>) are connected with the heat dissipation lateral board (<NUM>), so as to form the two accommodating spaces (<NUM>) between the heat dissipation board assembly (<NUM>) and the fixing frame body (<NUM>).