Patent Description:
An inverter is an electronic device for converting DC power to AC power by, for example but not limited to, a high frequency bridge circuit. The elements which requires heat dissipation such as circuit boards, IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), passive components, and other components are usually arranged on a bottom case of the inverter. Therefore, a plurality of heat dissipation fins for further heat dissipation is disposed on an external surface of the bottom case of the inverter.

However, the most part of the heat is distributed in the bottom case of the aforementioned inverter, and an upper cover of the inverter is in a relatively low temperature. Therefore, a heat dissipation efficiency of the entire inverter will increase if the heat is conducted to the low-temperature upper cover. Temperature inside the device could be decreased and a durability of the product could be extended.

<CIT> discloses an electronic device according to the preamble of claim <NUM> that may also be embodied as an inverter device. This electronic device does not include an air shroud fixed on the internal surface of the cover, for guiding an air flow inside the casing.

<CIT> discloses a high power amplifier having a casing that consists of two box-shaped members, namely a bottom casing and an upper casing. A shroud, a fan and a heat sink are disposed inside the casing to enhance the cooling of electric components disposed inside the casing.

<CIT> discloses a vehicular power converter, wherein a conductive plate is attached to the inside of a cover. Capacitors, representing heat source elements are thermally attached to an auxiliary heat sink and disposed inside the casing and are electrically connected to a circuit board disposed outside the casing.

<CIT> discloses an inverter device having a heat dissipation mechanism, comprising a casing, a plurality of heat source elements accommodated in the casing, and a heat dissipation structure. The casing is formed by a bottom, an upright and circumventing lateral wall and a cover. The heat dissipation structure comprises a plurality of heat dissipation fins connected to an external side of the bottom wall of the casing. The electronic components to be cooled may be directly fixed on the bottom wall of the casing or be disposed on a circuit board disposed spaced apart to the bottom wall inside the casing. The inverter device does not include another plurality of heat dissipation fins disposed inside the casing. A fan is not accommodated in the casing.

<CIT> discloses another heat dissipation structure for cooling electronic components disposed inside a sealed housing unit. A first fan is mounted within the housing unit and a second fan is mounted external to the housing unit. The airflow inside the housing unit is drawn across a heat sink from an outer portion thereof to an inner portion thereof. External to the housing unit airflow is forced through heat sinks from an interior portion thereof to an exterior portion thereof. Thereby a counter current thermal exchange mechanism is established.

It is an object of the present invention to provide an enhanced inverter device having an improved efficiency of heat dissipation and being more durable.

This problem is solved by an inverter device as claimed by claim <NUM>. Further advantageous embodiments are the subject-matter of the dependent claims.

Accordingly, the airflow in the casing is accelerated by the fan, and the airflow is thereby driven to flow through the heat dissipation structure, heat is absorbed from the airflow by the heat dissipation structure and the heat is further transferred to an external surface of the cover, heat could be dissipated more efficiently from the inverter device via the cover in relatively low temperature. Thereby, an efficiency of heat dissipation of the inverter device is improved and the inverter device is therefore more durable.

Accordingly, the plurality of heat dissipation fins is bent to form a curved segment, the curved segment is disposed on the cover to extend a heat dissipation area of the heat dissipation fin, airflow channels could be extended thereby to maintain the heat in the heat dissipation structure, and the heat is further dissipated from the cover.

The present disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings. However, scopes of the present disclosure should not be limited thereby.

According to an inverter device having a heat dissipation mechanism shown in <FIG> of the present disclosure, an inverter device <NUM> mainly has a casing <NUM>, one or a plurality of heat source elements <NUM>, a heat dissipation structure <NUM> and one or a plurality of fans <NUM>.

According to <FIG>, the casing <NUM> has a base <NUM> and a cover <NUM>, the base <NUM> is covered by the cover <NUM>, an internal surface <NUM> and an external surface <NUM> are oppositely defined on the cover <NUM>, and the internal surface <NUM> is arranged corresponding to the base <NUM>.

Specifically, the base <NUM> has a bottom wall <NUM> and a lateral wall <NUM> surrounding the bottom wall <NUM>. The internal surface <NUM> is arranged corresponding to the bottom wall <NUM>. A plurality of aiding fins <NUM> is one piece extended from or bonded on an external side of the bottom wall <NUM>, and the plurality of aiding fins <NUM> are used for dissipation heat accumulated in the bottom wall <NUM>.

According to present embodiment shown in <FIG> and <FIG>, a plurality of heat source elements <NUM> is provided, the respective heat source elements <NUM> are accommodated in the casing <NUM> and arranged on the bottom wall <NUM> of the base <NUM>. The heat source elements <NUM> are electronic elements of the inverter device <NUM>. the plurality of heat source elements <NUM> includes a circuit board <NUM>, a plurality of capacitors <NUM>, power semiconductor components <NUM> such as IGBTs or MOSFETs, relay(s) <NUM>, common mode choke(s) <NUM> and inductor(s) <NUM>. The circuit board <NUM> is fixed on the bottom wall <NUM>, and the capacitors <NUM>, the power semiconductor components <NUM> such as IGBTs or MOSFETs, the relay(s) <NUM> and the common mode choke(s) <NUM> are fixed on the circuit board <NUM>. Furthermore, according to the present embodiment, the inductor(s) <NUM> are arranged at one side of the circuit board <NUM> and fixed on the bottom wall <NUM>, but scopes of the present disclosure should not be limited thereby, the inductor(s) <NUM> alternatively could be fixed on the circuit board <NUM>. Heat generated by the aforementioned respective heat source elements <NUM> are transferred to the bottom wall <NUM> and further dissipated from the aiding fins <NUM>.

Accordingly, the power semiconductor components <NUM> such as IGBTs or MOSFETs are used as switches of a power conversion circuit such as DC/AC or DC/DC conversion circuits. The relay (Relay) <NUM> is used to disconnect external power input. The common mode choke <NUM> is a common mode inductor used to solve Electromagnetic Interference (EMI). Furthermore, a plurality of supporting columns <NUM> fixed on the bottom wall <NUM> and arranged at one side of the circuit board <NUM> are accommodated in the casing <NUM>, and the supporting column <NUM> is used for electrical connection, supporting the circuit board <NUM> or other circuit board(s).

Moreover, the number of the circuit board <NUM> is not limited to one according to aforementioned embodiment, a plurality of circuit boards <NUM> alternatively could be provided. The plurality of circuit boards <NUM> could be fixed on the bottom wall <NUM> and arranged in a plane or in a stack, and the plurality of capacitors <NUM>, the power semiconductor components <NUM>, and the relays <NUM>, and the common mode chokes <NUM> are respectively fixed on the circuit boards <NUM>.

Furthermore, when the aforementioned plurality of circuit boards <NUM> are provided, one part of the plurality of capacitors <NUM>, the power semiconductor components <NUM>, the relays <NUM> and the common mode chokes <NUM> could be arranged on the same circuit board, and another part of the plurality of capacitors <NUM>, the power semiconductor components <NUM>, the relays <NUM> and the common mode chokes <NUM> could be arranged on another circuit board(s). Accordingly, the inductor(s) <NUM> could be arranged at one side of the circuit board <NUM> or fixed on one of the circuit boards <NUM>.

According to <FIG>, <FIG> and <FIG>, the heat dissipation structure <NUM> is thermally contacted with the internal surface <NUM>. According to the heat dissipation structure <NUM> shown in the present embodiment, the heat dissipation structure <NUM> includes a plurality of heat dissipation fins <NUM> and a heat conductive plate <NUM>. One surface of the heat conductive plate <NUM> is thermally contacted with the internal surface <NUM>, and a plurality of heat dissipation fins <NUM> is connected to the other surface of the heat conductive plate <NUM>. The plurality of heat dissipation fins <NUM> are arranged with each other and two vents <NUM> are thereby defined corresponding to two ends of the heat dissipation fins <NUM>. However, scopes of the present disclosure should not be limited to the embodiment.

Furthermore, the heat dissipation structure <NUM> could be a vapor chamber or include a vapor chamber, and the vapor chamber is thermally contacted with the internal surface <NUM>. Alternatively, the heat dissipation structure <NUM> could be a heat pipe or include a heat sink and one or a plurality of heat pipes, and the heat sink is thermally contacted with the internal surface <NUM> and the heat pipes are inserted into the heat sink.

Moreover, the heat conductive plate <NUM> is fixed on the internal surface <NUM> by adhesive od screw according to the present embodiment, namely the heat conductive plate <NUM> and the cover <NUM> could be assembled in two separated parts. However, scopes of the present disclosure should not be limited thereby, the heat conductive plate <NUM> and the cover <NUM> alternatively cloud be one piece formed.

According to the present embodiment shown in <FIG>, <FIG> and <FIG>, a fan <NUM> is accommodated in the casing <NUM> and arranged corresponding to one of the vents <NUM>. However, scopes of the present disclosure should not be limited thereby, the fan <NUM> could be arranged anywhere in the casing <NUM>, but the fan <NUM> should be arranged corresponding to position of the heat dissipation structure <NUM> and airflow driven by the fan <NUM> should flow through heat dissipation structure <NUM>.

Accordingly, the fan <NUM> is used to accelerate airflow in the casing <NUM>, and the heat dissipation structure <NUM> is used to absorb heat from the air in the casing <NUM> and transfer the heat to the external surface <NUM> of the cover <NUM>.

According to <FIG>, <FIG> and <FIG>, the inverter device <NUM> according to the present disclosure further includes an air shroud <NUM>. The air shroud <NUM> is fixed on the internal surface <NUM> and the plurality of heat dissipation fins <NUM> are covered thereby. Two openings <NUM> are defined on the air shroud <NUM> corresponding to the two vents <NUM>, and an extension segment <NUM> arranged between one of the openings <NUM> and the plurality of heat dissipation fins <NUM> is defined on the air shroud <NUM>. The fan <NUM> is arranged on the extension segment <NUM>, and the fan <NUM> is therefore arranged corresponding to one of the openings <NUM>.

According to the operated inverter device <NUM> shown in <FIG> of the present disclosure, the heat dissipation structure <NUM> is thermally contacted with the internal surface <NUM> of the cover <NUM>. The fan <NUM> is arranged corresponding to the heat dissipation structure <NUM>, airflow in the casing <NUM> is accelerated by the fan <NUM> and driven to flow through the heat dissipation structure <NUM>, and heat is absorbed from the airflow via the heat dissipation structure <NUM> and the heat is further transferred to the external surface <NUM> of the cover <NUM>. Thereby, heat could be more efficiently dissipated from the inverter device <NUM> through the cover <NUM> in relatively low temperature. Therefore, an efficiency of heat dissipation of the inverter device <NUM> is improved and the inverter device <NUM> is more durable.

Moreover, the inverter device <NUM> of the present disclosure further includes an air shroud <NUM> covering the plurality of heat dissipation fins <NUM>. Two openings <NUM> are defined on the air shroud <NUM>, the fan <NUM> is arranged corresponding to one of the openings <NUM>, and the airflow driven by the fan <NUM> thereby could be guided to flow through the heat dissipation structure <NUM> and heat could be more efficiently transferred to the heat dissipation structure <NUM>.

According to another embodiment of the present disclosure shown in <FIG>, the inverter device <NUM> is almost the same as the embodiments shown in <FIG>, the difference between the embodiment shown in <FIG> and the embodiment shown in <FIG> is that the plurality of heat dissipation fins <NUM> are bent to form one or a plurality of curved segments <NUM>. The curved segments <NUM> are arranged on the cover <NUM> for turning extending direction, and an area for heat exchange of the plurality of heat dissipation fins <NUM> is thereby extended, and air flow channels are extended so that the heat is maintained in the heat dissipation structure <NUM> and further dissipated via the cover <NUM>.

Claim 1:
An inverter device having a heat dissipation mechanism, comprising a casing (<NUM>), wherein a plurality of heat source elements (<NUM>), a heat dissipation structure (<NUM>) and at least one fan (<NUM>) are accommodated in the casing (<NUM>); wherein
the casing (<NUM>) comprises a base (<NUM>) and a cover (<NUM>), the base (<NUM>) comprises a bottom wall (<NUM>) and a lateral wall (<NUM>) protruding from and surrounding the bottom wall (<NUM>), the base being covered by the cover (<NUM>), a plurality of aiding fins (<NUM>) is connected to an external side of the bottom wall (<NUM>), and the plurality of heat source elements (<NUM>) is arranged on a circuit board (<NUM>) fixed on the bottom wall (<NUM>) of the base (<NUM>);
an internal surface (<NUM>) and an external surface (<NUM>) are oppositely defined on the cover (<NUM>), and the internal surface (<NUM>) is arranged corresponding to the base (<NUM>); and
the heat dissipation structure (<NUM>) comprises a plurality of heat dissipation fins (<NUM>) arranged parallel with each other and a heat conductive plate (<NUM>); wherein
one surface of the heat conductive plate (<NUM>) is thermally contacted with the internal surface (<NUM>) and the plurality of heat dissipation fins (<NUM>) is connected with the other surface of the heat conductive plate (<NUM>),
a vent (<NUM>) is defined corresponding to each of the two ends of the heat dissipation fins (<NUM>), and
an air shroud (<NUM>) is fixed on the internal surface (<NUM>) of the cover (<NUM>) covering the plurality of heat dissipation fins (<NUM>), wherein openings (<NUM>) are defined on the air shroud (<NUM>) corresponding to each of the vents (<NUM>) and the at least one fan (<NUM>) is arranged corresponding to one of the openings (<NUM>) and vents (<NUM>).