JP2000013063A - Microwave communication apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable restraining enlargement of radiating fins when power of a microwave communication apparatus is increased, and excluding use of expensive components when the apparatus is constituted. SOLUTION: A microwave communication apparatus is provided with a cabinet 1 where a high power device 4 is mounted and a plurality of radiating fins 1a are formed on back of the mounting surface, a shield frame 3 which is fixed to the cabinet 1 and caps the high power device 4, and an outer lid 2 which has a plurality of radiating fins 2a formed on the surface, is bonded to the cabinet 1, caps the shield frame 3 and keeps airtightness in the cabinet 1. The above microwave communication apparatus has a structure in which the high power device 4, the shield frame 3 and the outer lid 2 are in contact with each other at least at a position where these are superposed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave communication device for satellite communication, and more particularly to a microwave communication device capable of inexpensively constructing a structure having good heat radiation.

[0002]

2. Description of the Related Art Generally, a microwave communication device for satellite communication includes, as shown in FIG. 3, a parabolic antenna 11, a horn antenna 12 disposed at a focal point thereof, a converter 13 connected to a subsequent stage, and The converter 1
3 comprises a modem 15 connected by a cable 14 at the subsequent stage.

[0003] When the microwave communication device is a transmitter, the converter 13 is an up-converter that converts a transmission frequency to a high frequency, and when the microwave communication device is a receiver, it is a down-converter that reduces the reception frequency to an intermediate frequency.

[0004] The assembly of the converter 13 and the horn antenna 12 is called an outdoor unit (ODU) because it is arranged outdoors as opposed to the modem 15 arranged indoors.

In general, many high-frequency components have poor power conversion efficiency, and in particular, components mounted on an ODU have a high output, so that a large amount of heat is released. Among them, particularly, in the case of a high power device such as a high power amplifier, the calorific value accounts for about 50 to 60% of the calorific value of the entire ODU.

Therefore, a structure as shown in FIGS. 4 and 5 has conventionally been adopted. FIG. 4 is a cross-sectional view of the converter 13 shown in FIG. 3, and FIG. 5 is a partially enlarged view of a portion A shown in FIG. In these figures, 1 is a housing, 1
a is a heat radiation fin provided on the housing 1, 2 is an outer cover covering the housing 1, 2 a is a heat radiation fin provided on the outer cover 2, 3 is a space surrounded by the housing 1 and the outer cover 2. , And 3a is a partition wall provided on the shield frame 3, 4 is fixed to the housing 1, and a high-power amplifier ( HPA) or the like, 6 is a substrate made of Teflon, glass epoxy, or the like, and the surface of which is patterned with copper foil, 7
Is a waterproof O-ring sandwiched between the housing 1 and the outer lid 2, 9
Reference numerals a to 9c denote screws for fastening.

As shown in the figure, a high power device 4 and a substrate 6 are mounted on a housing 1, and a radiating fin 1a is formed on the back surface of the mounting surface. This radiation fin 1a
Is formed by adhering to the housing 1 or integrally processing (molding). By bringing the back surface of the package of the high power device 4 into close contact with the housing 1, the GND as a microwave circuit is reduced. And the radiation fin 1a
To the heat.

The shield frame 3 covers the high-power device 4 fixed to the housing 1 and forms a cavity surrounding the high-power device 4 with its partition wall 3a. This makes the spatial electric field around the high-power device independent and prevents interference with other circuits.

The outer lid 2 is mainly intended for waterproofing, covers the shield frame 3, and usually has an O-ring 7 sandwiched between the outer lid 2 and the housing 1. Fins 2a are formed on the surface to dissipate heat transmitted from the housing 1.

The casing 1, the outer lid 2, and the shield frame 3 are mainly obtained by cutting from an aluminum ingot or casting by aluminum die casting.

[0011]

In the structure described above, in recent years, a problem associated with heat radiation has become apparent, especially in the case where the demand for higher power has been increased particularly in a transmitter.

That is, the power consumed as heat increases with the increase in power, but as long as the conventional structure is adopted,
The only way to increase heat radiation is to increase the number of heat radiation fins or lengthen the heat radiation fins. With such an increase in the size of the radiation fins, the housing becomes large and heavy, which may impair the appeal of the product as an ODU. In addition, in the case of integral molding, it is not easy to lengthen the radiation fins, and there is also a problem that advanced mold making technology and casting technology are required.

On the other hand, in order to cope with such a problem, for example, a cooling device such as a Floriner Liquid Heat Sink (trade name, manufactured by Sumitomo 3M) or the like is provided on the surface of a mounting component such as a high power device and a space for covering the component. There is a method of interposing a pack containing the agent. According to this, since the heat of the high power device can be released from the contact surface with the housing to the radiating fins and the heat can be released to the opposite lid side, it is not necessary to make the radiating fins so large. .

However, such a pack containing a coolant is expensive, and its size cannot be freely selected. In particular, it is difficult to adopt such a pack for a high-density mounting or space-saving such as an ODU. Since it must be made in a special size for the product, the cost is further increased.

[0015]

In order to solve the above problems, a microwave communication device according to the present invention has a high power device mounted thereon, and a plurality of heat radiation fins are formed on the back surface of the high power device mounting surface. A housing, a shield frame fixed to the housing and covering the high-power device, and a plurality of radiating fins formed on the surface to be fixed to the housing and cover the shield frame and hermetically seal the housing. And a shield frame and the outer lid are in contact with each other at least at a position where they overlap with each other.

Further, the high-power device and the shield frame are in contact with each other via an elastic and heat-transferring sheet material, and the shield frame and the outer lid are formed on the shield frame or the projection formed on the outer lid. The contact is made through the contact.

[0017] Further, there is provided a waterproof O-ring sandwiched between the contact surface of the shield frame and the outer lid, and a screw for fastening the shield frame and the outer lid, wherein the screw penetrates the outer lid. It is screwed into the shield frame, and the screwed portion is within the circle of the O-ring.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The same or corresponding components are denoted by the same reference symbols throughout the drawings, and description thereof will not be repeated.

FIGS. 1 and 2 show an embodiment of the present invention. FIG. 1 is a sectional view of a converter, and FIG.
Partial enlarged views of part B are shown. In these figures, 5 indicates a sheet material sandwiched between the high power device 4 and the shield frame 3, and 8 indicates a waterproof O-ring made of nitrile rubber, silicon rubber, or the like.

As shown in FIG. 1, the high power device 4
A sheet material 5 is interposed between the shield frame 3 and the shield frame 3, and heat of the high power device 4 is transmitted to the shield frame 3 via the sheet material 5. The sheet material 5 preferably has elasticity and is easily deformed so as not to require high dimensional accuracy in the gap between the shield frame 3 and the high-power device 4, and preferably has an appropriate resistance to heat generation of the high-power device. One example is silicon rubber. High power device 4 with silicon rubber as it is
In order to improve the adhesion between the heat shield and the shield frame 3 and to transfer heat between them, a filler such as carbon powder may be mixed in the heat conductor.

Further, as can be seen from FIG.
A convex portion 3b is formed on the upper surface of the cover frame 3 and comes into contact with the outer cover 2 so that the heat of the shield frame 3 is transmitted to the outer cover 2. Incidentally, the convex portion 3b can be formed by aluminum die-casting together with other portions of the shield frame 3, and is formed at a portion overlapping the high power device 4. The protrusion 3b and the outer lid 2 are fastened and fastened by screws 10, and an O-ring groove is formed in a contact surface of the protrusion 3b with the outer lid 2, and an O-ring 8 is inserted therein. The O-ring is pinched and crushed between the convex portion 3b and the outer lid 2, and exhibits waterproofness.

In order to configure as shown in the figure, first, the substrate 6 is fixed to the housing 1, and then the high power device 4 is fixed by screws 9a. The shield frame 3 is fastened together with the housing 1 with the screws 9b with the substrate 6 interposed therebetween. At this time, the sheet material 5 is sandwiched between the high power device 4 and the shield frame 3. Next, an O-ring 7 is provided on the housing 1 and the shield frame 3, respectively.
8, the outer lid 2 is fixed with screws 9c. Next, screw 10
Is screwed into the shield frame 3 through a through hole (not shown) provided in the outer lid 2. At this time, screw 1 to shield frame 3
The threaded portion of 0 is within the circle of the O-ring 8.

With such a structure, the heat of the high power device is conducted to the outer lid 2 via the sheet material 5 and the shield frame 3 at the shortest distance, so that the heat is quickly radiated by the radiating fins of the outer lid 2, and as a whole, Heat dissipation efficiency is improved. In addition, the screws 10 can improve the adhesion between the outer lid 2 and the shield frame 3.

That is, the shield frame 3 can be provided with two functions, that is, a microwave shield and a heat radiating bypass, and can be manufactured at low cost without using a special heat radiating material such as the above-mentioned pack containing a coolant. Efficient heat dissipation can be achieved.

Further, by making the outer lid 2 and the shield frame 3 come into contact with each other via the convex portion 3b, even if the convex portion 3b and the housing 1 come into contact with the outer lid 2 at the same time, the projection 3b and the housing 1 Since the outer lid 2 is appropriately deformed in a portion other than the contact portion, a gap due to a dimensional error of the protrusion 3b or the housing 1 in the contact portion does not occur. If the outer lid 2 and the shield frame 3 are in full contact with each other without any intervening protrusion, if the thickness of the shield frame 3 is larger than a predetermined dimension, a screw 9 is inserted between the outer lid 2 and the housing 1.
There is a large possibility that a gap that cannot be eliminated even if c is tightened is generated. This is also the outer lid 2 and shield frame 3
The same can be said for the case where is integrally molded.

Even if the outer lid 2 has a through hole for inserting the screw 10, since the screwing point of the screw 10 into the shield frame 3 is within the circle of the O-ring 8, water intrusion there. Can be stopped.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to this, and various modifications can be made.
For example, the shield frame 3 may be made of a metal having higher thermal conductivity, such as copper, instead of aluminum.

Further, in the above embodiment, the projection is formed on the shield frame, but the projection may be formed on the outer lid. However, in order for heat conduction between the shield frame and the outer lid to be sufficiently performed, it is preferable that this convex portion is formed at least at a position overlapping with a high power device as a heat source. The size of the convex portion is appropriately selected through a generally performed thermal analysis, experiment, or the like. The projections can be formed by integral molding as described above, but can also be fixed by a block-shaped metal piece. However, when the metal pieces are fixed, care must be taken so that poor contact does not occur on the fixed surface.

The sheet material 5 can be a radio wave absorber that is generally attached to a shield frame and used. The O-ring 8 mounted on the shield frame 3 can be a material used for a joint between an ODU and a horn antenna. it can. Therefore, the heat radiation structure can be obtained at a low cost because it does not involve a large change in the process and a large increase in the material cost.

[0030]

As described above, according to the present invention,
In addition to the conventional heat dissipation path, a heat dissipation path that directly conducts heat in the direction of the outer lid can be provided, and the heat dissipation of the microwave communication device can be further improved.

Further, the sheet material is sandwiched between the high-power device and the shield frame, and the shield frame and the outer lid are brought into contact with each other via the convex portion formed on either of them, so that the confidentiality inside the housing can be easily reduced. The number of heat radiation paths can be increased without loss, and the heat generated by the high power device is efficiently radiated.

Further, an O-ring is sandwiched between the contact surfaces of the shield frame and the outer lid, a screw is penetrated into the outer lid, and this is screwed into the shield frame. By making the entrance part within the circle of the O-ring, the adhesion between the outer lid and the shield frame is improved without impairing the confidentiality,
It is easier to conduct heat.

In general, even if the microwave communication device is made to have a high power, it is possible to suppress an increase in the size of the radiation fin.
Moreover, since it is not necessary to use expensive parts to construct,
It can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a diagram illustrating a microwave communication device.

FIG. 4 is a diagram showing a conventional example.

FIG. 5 is a partially enlarged view of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 1a, 2a Radiation fin 2 Outer lid 3 Shield frame 3b Convex part 4 High power device 5 Sheet material 6 Substrate 7, 8 O-ring 9a-9c, 10 screw

Claims (3)

[Claims] 1. A housing on which a high-power device is mounted, and a plurality of radiating fins formed on a back surface of the high-power device mounting surface, and a shield frame fixed to the housing and covering the high-power device. A microwave communicator comprising: a plurality of radiating fins formed on the surface, fixed to the housing, and covering the shield frame to keep an airtight inside the housing; A microwave communication device, wherein the shield frame and the outer lid are in contact with each other at least at a position where they overlap. 2. The high-power device and the shield frame are in contact with each other via an elastic and heat-transferring sheet material.
The microwave communication device according to claim 1, wherein the shield frame and the outer lid are in contact with each other via a convex portion formed on the shield frame or the outer lid. 3. A waterproof O-ring sandwiched between contact surfaces of the shield frame and the outer lid, and a screw for fastening the shield frame and the outer lid, wherein the screw penetrates the outer lid. The microwave communication device according to claim 2, wherein the microwave communication device is screwed into the shield frame, and the screwed portion is within a circle of the O-ring.