JPS6345730Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electron beam tube such as a traveling wave tube, and particularly to a collector electrode cooling device for a traveling wave tube in which the collector electrode is electrically insulated from a ground point.

Conventionally, this type of cooling device has been designed to fit the cylindrical collector electrode of the electron beam tube through a heat transfer plate and an electrical insulating plate that form a heat transfer path on the opposite side of the holding plate to which the heat dissipation body is attached. A heat transfer block having holes is arranged, and the heat transfer block and heat transfer plate are fixed to an electrically insulating plate using manufacturing techniques such as metallization, plating, and soldering.

This type of cooling device has good heat dissipation characteristics and is useful, but there is a difference in the coefficient of thermal expansion between the metal such as copper that makes up the heat transfer block and heat transfer plate and the electrical insulation board made of alumina ceramic etc. For this reason, as the surface area of the joint surfaces of the heat transfer block and the heat transfer plate with the electrically insulating plate increases, the thermal stress applied to the joint surfaces due to the temperature rise of the collector electrode during soldering and operation increases.

As a result, there is a high risk that minute cracks will occur in the electrical insulating plate, which has poor mechanical strength among the components of the cooling system, reducing the withstand pressure between the heat transfer block and the heat transfer plate or holding plate. In addition, there was a fear that the yield of products such as traveling wave tubes would decrease. In order to eliminate these drawbacks of the conventional structure, Utility Application No. 1866/1973 has provided one or more grooves in the joint surface of the heat transfer block and the heat transfer plate with the electrically insulating plate. We have provided a collector electrode cooling device for an electron beam tube.

A further object of the present invention is to provide a heat sink structure that is effective in alleviating thermal stress due to differences in thermal expansion coefficients of different materials in a heat sink structure that has a substantially large adhesive area.

The present invention enables a heat transfer block to be used in an electron beam tube collector electrode cooling device in which a heat transfer block having a fitting hole for housing the electron beam tube collector is adhered to a holding plate through a heat transfer plate and an electrically insulating plate. It is a laminate of flexible thin plates, and the thermal stress that occurs at the bonded area between the heat transfer block and the electrical insulating plate is alleviated by flexing the thin plates of the laminate, which prevents micro-cracks from occurring in the electrical insulating plate. It is characterized by preventing

The present invention will be explained below using examples.

1 and 2 are partial axial sectional views of an embodiment of the collector electrode cooling device for an electron beam tube according to the present invention,
and its AA sectional view, particularly showing the case where a traveling wave tube is used as the electron beam tube. In the same figure, traveling wave tube (only the collecting electrode side part is shown) 1
A cooling device 12 for cooling the collector electrode 11 of the collector electrode 1
It is comprised of a heat transfer block 13, a heat transfer plate 14, and an electrically insulating plate 15 for once conducting the heat generated in the heat exchanger 1. The heat transfer block 13 is a laminated body of thin plates, and a cylindrical fitting hole 16 having an inner diameter equivalent to the outer diameter of the collector electrode 11 is bored near the center in a direction perpendicular to the lamination direction. A groove 30 is formed in the axial direction of the fitting hole 16 on the joint surface of the heat transfer block 13 with the electrically insulating plate 15 so as to divide the heat transfer block 13 into two. The heat exchanger plate 14 is completely divided into four parts with gaps 31, and electrically insulating plates 15 are bonded to each other. The gap 31 is provided so that the surface area of the joint surface is divided into four equal parts. The groove 30 is provided so that the surface area of the joint surface is divided into two equal parts. The electrical insulating board 15 is made of a beryllia ceramic board that is an electrical insulator and has good thermal conductivity, and a heat transfer block 13 and a heat transfer plate 14 are bonded to both sides by soldering or brazing as shown in the figure. ing. The heat transfer block 13 and the collector electrode 11 are bonded together by soldering or brazing. The heat generated in the collector electrode 11 is well conducted to the heat transfer block 13 with low thermal resistance. Heat transfer block 13 and heat transfer plate 14
It is better to use copper, etc., which has high thermal conductivity. The slow wave circuit 23 and the collector electrode 11 are electrically insulated by an insulating cylinder 24 interposed therebetween. This slow wave circuit 23
A magnetic focusing device 2 for focusing the electron beam is installed around the outer periphery of the
5 is arranged and fixed together with the cooling device 12 on a metal holding plate 26 by screwing (not shown) or the like.

In the collector electrode cooling device for an electron beam tube having such a structure, the heat generated in the collector electrode 11 is transferred in the order of the heat transfer block 13, the electric insulating plate 15, the heat transfer plate 14, and the holding plate 26 like a heat conduction path 27. and is dissipated by suitable heat dissipating fins (not shown) provided on the bottom surface of the retaining plate 26.

As described above, in the cooling device shown in the embodiment of the present invention, the grooves 30 are provided on the joint surface of the heat transfer block 13 with the electrical insulating plate 15 to divide the joint surface into equal parts. The electrical insulating plate 15 also divides the heat exchanger plate 14 into four parts.
Since the heat transfer block 13 is a laminate of flexible thin plates, the joint surface that occurs when different materials with different coefficients of thermal expansion are bonded by soldering or brazing is At the same time as relieving thermal stress,
The heat transfer block 1 also responds to the rapid heating shock applied to the heat transfer block 13 from the collector electrode 11 of the traveling wave tube.
Deformation of the thin plate of the heat transfer block and groove 30
This can be alleviated by In addition, the thermal expansion of the heat transfer plate 14 can be alleviated by the gap 31, and micro-cracks that are likely to occur in the electrical insulating plate 15, which has weak mechanical strength, can be prevented, and the withstand voltage will not be lowered. Further, although the heat transfer block 13 is made of a dense laminate of flexible thin plates, if an appropriate gap is provided, the flexibility will be further improved and thermal stress can be alleviated.

In the above embodiment, a traveling wave tube is used as the electron beam tube, but the present invention is not limited to this, and can of course be applied as a collector electrode cooling device for other electron beam tubes. It is. In addition, the heat transfer block was divided into two equal parts from the groove 30, and the gap between the joint surfaces of the heat transfer plates was made into a cross and divided into four parts. However, considering the power consumption of the electron beam tube and the area of the joint surface, the number of grooves and gaps was changed. Of course, it is also possible to arbitrarily select the location.

[Brief explanation of drawings]

FIG. 1 is a partial axial sectional view showing an embodiment of the collector electrode cooling device for an electron beam tube according to the present invention, and FIG. 2 is a sectional view taken along line A-A in FIG. DESCRIPTION OF SYMBOLS 1...Travelling wave tube, 11...Collecting electrode, 12...Cooling device, 13...Heat transfer block, 14...Heat transfer plate, 15...Electrical insulating plate, 16...Fitting hole, 23
... Slow wave circuit, 24 ... Insulating cylinder, 25 ... Magnetic focusing device, 26 ... Holding plate, 27 ... Heat conduction path,
30...Groove, 31...Gap.

Claims (1)

[Scope of utility model registration request] In an electron beam tube collector electrode cooling device in which a heat transfer block having a fitting hole for housing the electron beam tube collector is adhered to a holding plate through a heat transfer plate and an electrical insulating plate, the heat transfer block is flexible. 1. A collector electrode cooling device for an electron beam tube, characterized in that the laminated body is made of a laminate of thin plates having the following structure, and a fitting hole for accommodating the collector electrode of the electron beam tube is provided in the laminate in a direction perpendicular to the lamination direction.