US-12621954-B2 - Electronic device

US12621954B2US 12621954 B2US12621954 B2US 12621954B2US-12621954-B2

Abstract

Provided is an electronic device that can prevent an increase in a temperature of an internal electronic component, and prevent a heat influence on adjacent electronic devices or the like. The electronic device includes: a circuit board on which a heat-generating element configured to generate heat is mounted; a housing in which the circuit board is housed; a heat dissipation portion connected to the housing and configured to dissipate heat; a heat transfer member disposed between the heat-generating element and the heat dissipation portion, and configured to transfer heat generated by the heat-generating element to the heat dissipation portion; and a housing cover provided on a side of the heat dissipation portion opposite to a side of the heat transfer member, in which a convection area that is a space where air convects is provided between the heat dissipation portion and the housing cover.

Inventors

Koumei YOSHIDA
Goro HAMAMOTO

Assignees

HITACHI, LTD.

Dates

Publication Date: 20260505
Application Date: 20220307
Priority Date: 20210622

Claims (2)

1 . An electronic device comprising: a circuit board on which a heat-generating element configured to generate heat is mounted; a housing in which the circuit board is housed; a heat dissipation portion connected to the housing and configured to dissipate heat; a heat transfer member disposed between the heat-generating element and the heat dissipation portion, and configured to transfer heat generated by the heat-generating element to the heat dissipation portion; and a housing cover provided on a side of the heat dissipation portion opposite to a side of the heat transfer member, wherein a first convection area that is a space where air convection occurs between the heat dissipation portion and the housing cover is provided opposite one face of the heat transfer member and is the only convection area between the heat dissipation portion and the housing cover, the first convection area having a first opening adjacent a lower end of the housing cover between the heat dissipation portion and the housing cover for allowing air to flow into the first convection area and a second opening at an upper end of the housing cover between the heat dissipation portion and the housing cover for discharging air from the first convection area to an outside, the housing defines a second convection area and comprises an air intake ventilation hole, provided in a lower surface of the housing, for taking air into the housing, and an air exhaust ventilation hole, provided in an upper surface of the housing, for discharging the air in the housing to the outside, the air intake ventilation hole and the air exhaust ventilation hole are separate from the first and second openings, the air intake ventilation hole and first opening are provided in a plane defined by the lower surface of the housing, and the air exhaust ventilation hole and second opening are provided in a plane defined by the upper surface of the housing, an airflow is configured to flow through the air intake ventilation hole, along opposite side surfaces of the heat transfer member, and is exhausted through the air exhaust ventilation hole from an upper portion of the heat transfer member, and the heat transfer member has a cross-sectional shape that does not interfere with the airflow.
2 . The electronic device according to claim 1 , wherein the heat transfer member has a cylindrical shape or a polygonal column shape having five or more corners.

Description

TECHNICAL FIELD The present invention relates to an electronic device including a heat-generating element, such as an electronic component disposed on a circuit board. BACKGROUND ART Many electronic devices include electronic circuits in each of which electronic components are mounted on a printed wiring board (PWB). The electronic components such as an integrated circuit, a transistor, a diode, a resistor, and a capacitor are soldered on a PWB on which wiring is formed by lithography to form a printed circuit board (PCB). A certain type of electronic component generates heat due to an operation, and is thus used together with a cooling structure for heat dissipation. As the cooling structure, a heat sink, a heat pipe, or the like is often used. Generally, when heat generated by an electronic component is to be dissipated to the heat sink that dissipates heat to outside, a housing, or the like, each heat-generating component such as an integrated circuit is attached via a heat transfer member such as a heat pipe or a metal block. In recent years, an amount of information to be processed by the electronic device increases, and an integrated circuit that can more swiftly operate is used, and therefore a heat generation amount also tends to increase. Therefore, a cooling structure that efficiently cools the electronic components is required. In order to improve cooling efficiency, forced air cooling in which a fan or the like is used and a heat transfer amount based on convection is increased is efficient. However, for reasons that in an industrial device for which long-term reliability is required, cooling capacity when the fan is stopped due to a failure or the like remarkably deteriorates, and a structure that supplies a power supply to the fan is necessary, improvement in a natural cooling structure in which the PCB and the housing themselves are used as main heat-dissipating bodies is being examined. Generally, a method for mounting the heat sink on the heat-generating component, a structure using a heat dissipation heat pipe as a heat transfer path to the housing in contact with the atmosphere, and a method using a metal block having high thermal conductivity, typically aluminum (Al), for the same purpose are well known. For example, in an electronic apparatus disclosed in the following PTL 1, a heat transfer member is provided between an upper portion of a heat-generating element and a housing, and heat is transferred to the housing via the heat transfer member, thereby dissipating the heat. CITATION LIST Patent Literature PTL 1: JP2016-143769A SUMMARY OF INVENTION Technical Problem However, when the electronic apparatus disclosed in PTL 1 is applied to a configuration in which a plurality of electronic apparatuses are adjacent to one another, problems may occur. Since the electronic apparatus disclosed in PTL 1 dissipates heat to the housing, the heat may be transferred to other electronic apparatuses adjacent to a housing heat dissipation surface, and inside of other adjacent electronic apparatuses is heated, so that there is a problem that an electronic component malfunctions or life is shortened. Further, since the heat dissipation surface and other electronic apparatuses (electronic devices) are adjacent to each other, there is no space for dissipating the heat, and there is also a problem that an increase in a temperature inside the electronic apparatus itself is not prevented. The invention has been made to solve the problems described above, and an object thereof is to provide an electronic device that can prevent an increase in a temperature of an internal electronic component, and prevent a heat influence on adjacent electronic devices or the like. The object described above and other objects of the invention and novel features of the invention will become apparent from the description of the present specification and the accompanying drawings. Solution to Problem In order to achieve the object described above, an electronic device according to the invention includes: a circuit board on which a heat-generating element configured to generate heat is mounted; and a housing in which the circuit board is housed. The electronic device according to the invention further includes: a heat dissipation portion connected to the housing and configured to dissipate heat; a heat transfer member disposed between the heat-generating element and the heat dissipation portion, and configured to transfer heat generated by the heat-generating element to the heat dissipation portion; and a housing cover provided on a side of the heat dissipation portion opposite to a side of the heat transfer member. In addition, in the electronic device according to the invention, a convection area that is a space where air convects is provided between the heat dissipation portion and the housing cover. Advantageous Effects of Invention According to an electronic device of the invention described above, since the heat generated by