JP2011192459A - Magnetron, and device using microwaves - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently cool an anode cylinder and permanent magnets, and to prevent a cooling member itself from enlarging, while restraining variation in the cooling performance to the permanent magnets. <P>SOLUTION: The magnetron is provided with an anode cylinder, permanent magnets fitted on both ends of the anode cylinder, a magnetic yoke housing the anode cylinder and the permanent magnets inside, a cooling member housing the anode cylinder inside, and with at least a part of it being fixed to the anode cylinder, and a connecting part arranged between the magnetic yoke and the cooling member. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a magnetron and a microwave utilization device.

  The configuration of the liquid-cooled magnetron will be described with reference to FIGS. 6 (a) and 6 (b). FIG. 6A is an overall configuration diagram of a conventional magnetron 100, and FIG. 6B is a perspective view of the cooling block 110. As shown in FIG. 6 (a), the magnetron 100 is in close contact with the outer peripheral surface of an anode cylinder (not shown) in the yoke 106, and a flow conduit through which a medium for cooling the anode cylinder flows. A cooling block 110 comprising 112 is provided. Further, the cooling block 110 is in thermal contact with a part of the permanent magnet 105 and the yoke 106 provided at both ends of the anode cylinder in the major axis direction (see Patent Document 1).

  As shown in FIG. 6B, the cooling block 110 is formed of a material having a cooling function, and an inlet 112A and an outlet 112B of the flow conduit 112 are provided on one side surface. The flow pipe 112 extends from the inlet 112A, is formed in the cooling block 110 in a substantially U shape so as to surround the anode cylinder, and reaches the outlet 112B.

  Note that when the flow pipe 112 is formed in the cooling block 110, the flow pipe parallel to one side of the cooling block 110 provided with the inlet 112A and the outlet 112B of the flow pipe 112 penetrates the cooling block 110. Then, it is formed by plugging with a cap 112C in FIG.

Japanese Patent Laid-Open No. 5-054855

  In general, an air-cooled magnetron cools a permanent magnet with direct wind, but a liquid-cooled magnetron indirectly cools a permanent magnet via a magnetic yoke, so its cooling effect is low. Further, when the magnetron is operated, the permanent magnet is demagnetized due to a high temperature, and the magnetic flux density is lowered, so that the anode voltage is lowered. As a result, the output of the liquid-cooled magnetron decreases.

  Further, in the liquid-cooled magnetron 100 described above, most of the cooling block 110 is in contact with the anode cylinder, so that the anode cylinder that becomes hot during operation of the magnetron 100 is a medium that flows in the flow pipe 112. It is cooled by. However, the portion of the cooling block 110 that is in thermal contact with the permanent magnet 105 is extremely small as compared with the entire cooling block 110, and a cooling effect on the permanent magnet 105 cannot be expected.

  Further, although the portion of the cooling block 110 that is in thermal contact with the permanent magnet 105 is small, it is integrally formed with the portion that is in contact with the anode cylinder, so that the cooling block 110 itself is increased in size.

  Furthermore, since the cooling block 110 is an integral block that covers the permanent magnet 105, the contact between the inner side of the cooling block 110 and the permanent magnet 105 is poor due to distortion of the outer diameter of the permanent magnet 105, and the heat dissipation effect is low. . In addition, if the cooling block 110 and the permanent magnet 105 are forcibly brought into contact with each other at the time of assembly, the permanent magnet 105 or the anode cylinder is deformed, which causes a problem in the oscillation characteristics of the magnetron 100.

  Further, in the above-described magnetron 100, when the cooling block 110 is manufactured, for example, when the cooling block 110 is positioned with respect to the anode cylinder, a slight gap is generated between the permanent magnet 105 and the permanent magnet 105. Therefore, the cooling performance of the cooling block 110 with respect to the permanent magnet 105 is not constant, and variation occurs.

  An object of the present invention is to efficiently cool the anode cylinder and the permanent magnet with a configuration in which the connecting portion provided separately from the cooling member can be brought into contact with the permanent magnet, thereby suppressing variations in the cooling performance for the permanent magnet. However, it is to provide a magnetron that can avoid an increase in size of the cooling member itself.

  The present invention includes an anode cylinder, permanent magnets provided at both ends of the anode cylinder, a magnetic yoke that accommodates the anode cylinder and the permanent magnet therein, and the anode cylinder accommodated therein. A magnetron is provided that includes a cooling member at least a part of which is fixed to the anode cylinder, and a connection portion disposed between the magnetic yoke and the cooling member.

  In the magnetron, the connection portion brings the permanent magnet and the cooling member into contact with each other.

  In the magnetron, the inner surface of the connection portion is in contact with the permanent magnet, and is fixed to the cooling member at a surface substantially perpendicular to the inner surface.

  In the magnetron, the connecting portion is any one of copper and a copper alloy, aluminum and an aluminum alloy.

  In the magnetron, the connection portion is a plurality of magnet contact pieces arranged along an outer peripheral surface of the permanent magnet that is annular, and the magnet contact pieces are a horizontal portion fixed to the cooling member; And a rising portion having one surface that is continuous with the horizontal portion and contacts the outer peripheral surface of the permanent magnet.

  In the magnetron, the connection portion is disposed along an outer peripheral surface of the annular permanent magnet, and the connection portion is continuous with the plurality of horizontal portions fixed to the cooling member, and the plurality of horizontal portions. And a rising portion having one surface in contact with the outer peripheral surface of the permanent magnet.

  In the magnetron, the connecting portion is a molded member made of an insulating resin having high thermal conductivity.

  In the magnetron, a heat conductive paste is applied between the connection portion and the permanent magnet and / or the connection portion and the cooling member.

  Moreover, this invention provides the microwave utilization apparatus provided with the said magnetron.

  According to the magnetron and the microwave utilization apparatus according to the present invention, the anode cylinder and the permanent magnet are efficiently cooled by the configuration in which the connecting portion provided separately from the cooling member can be brought into contact with the permanent magnet, and the permanent While suppressing variation in the cooling performance for the magnet, it is possible to avoid an increase in the size of the cooling member itself.

1 is an overall configuration diagram of a magnetron 1 according to an embodiment of the present invention. (A) Plan view of the cooling block 20, (b) Side view of the cooling block 20 (A) Plan view of cooling block 40, (b) Side view of cooling block 40 Perspective view of magnet contact piece 41B Perspective view of annular magnet contact portion 61B (A) Whole block diagram of conventional magnetron 100, (b) Perspective view of cooling block 110

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a magnetron 1 according to an embodiment of the present invention. The magnetron 1 shown in FIG. 1 mainly includes a magnetic yoke 4, an output unit 9 provided on the upper side of the magnetic yoke 4, and a filter 11 provided on the lower side of the magnetic yoke 4. The magnetic yoke 4 accommodates an anode cylinder 10, two annular permanent magnets 8 </ b> A and 8 </ b> B provided at both ends of the anode cylinder 10, and a cooling block 20 that covers the periphery of the anode cylinder 10. ing. The filter 11 includes a choke coil and a feedthrough capacitor 7.

  The magnetic yoke 4 is composed of a main body 4a and a lid portion 4b that closes the open end of the main body 4a, with one end opened and the other end closed. In the magnetic yoke 4, two annular permanent magnets 8 </ b> A and 8 </ b> B, an anode cylinder 10, and a cooling block 20 that covers the periphery of the anode cylinder 10 are accommodated.

  The anode cylinder 10 is restrained by the magnetic yoke 4 from the outside of the annular permanent magnets 8A and 8B arranged at both upper and lower ends. The annular permanent magnet 8B disposed on the lower side in the drawing is an input side magnet, and the annular permanent magnet 8A disposed on the upper side is an output side magnet. Inside the anode cylinder 10, anode vanes are arranged radially, and a cavity resonator is formed in a space surrounded by the adjacent anode vanes and the anode cylinder 10. In addition, a cathode structure is disposed at the center of the anode cylinder 10, and a space surrounded by the cathode structure and the anode vane is an action space.

  When the magnetron 1 according to the present embodiment is used, the interior of the magnetron 1 is evacuated and then a desired power is applied to the cathode structure to emit thermoelectrons, and a direct current is generated between the anode vane and the cathode structure. Apply high voltage. In the working space, a magnetic field is formed in a direction perpendicular to the direction in which the cathode assembly and the anode cylinder 10 are opposed by the annular permanent magnets 8A and 8B. By applying a DC high voltage between the anode vane and the cathode structure, electrons emitted from the cathode structure are extracted toward the anode vane. The electrons circulate while swirling by the electric and magnetic fields in the working space, and reach the anode vane. Energy due to the electron motion at this time is given to the cavity resonator and contributes to the oscillation of the magnetron.

  The cooling block 20 is formed separately from the main body 21A that contacts the anode cylinder 10 and the main body 21A, and contacts the annular permanent magnets 8A and 8B to cool the annular permanent magnets 8A and 8B. It is comprised with two magnet contact parts 21B.

  The two magnet contact portions 21B serve as connecting portions that connect the main body portion 21A and the annular permanent magnets 8A and 8B when viewed from the main body portion 21A.

  Further, the main body portion 21 </ b> A comes into contact with the anode cylinder 10 and mainly cools the anode cylinder 10. On the other hand, the two magnet contact portions 21B can be said to be connection portions when viewed from the main body portion 21A, but have a function of cooling the annular permanent magnets 8A and 8B. Therefore, the main body portion 21A and the two magnet contact portions 21B constituting the cooling block 20 function as a cooling member.

  The cooling block 20 has a first tightening portion 22A in a part thereof, and is fixed to the anode cylinder 10 by tightening the first screw 22B of the first tightening portion 22A after being attached to the anode cylinder 10. The Therefore, the cooling block 20 has the inner wall surface in contact with the outer wall surface of the anode cylinder 10. The cooling block 20 is set such that a slight gap is formed between the cooling block 20 and the magnetic yoke 4 when the cooling block 20 is fixed to the anode cylinder 10.

  The cooling block 20 is made of a metal having a high thermal conductivity, and a cooling liquid circulation pipe 23 for circulating the cooling liquid is formed therein. The cooling liquid flows into the cooling liquid circulation pipe 23. Therefore, the cooling block 20 can efficiently cool the anode cylinder 10 and the annular permanent magnets 8A and 8B that are in contact with the cooling block 20. In magnetron 1 according to the present embodiment, cooling block 20 is made of aluminum.

  Next, the configuration of the cooling block 20 will be described with reference to FIGS. 2 (a) and 2 (b). FIG. 2A is a plan view of the cooling block 20 as viewed from above, and FIG. 2B is a side view of the cooling block 20.

  The main body portion 21 </ b> A has a first housing portion 24 for housing the anode cylinder 10 and a cooling liquid circulation pipe 23 therein. In FIG. 2A, as indicated by a one-dot chain line, the cooling liquid circulation pipe 23 extends from the inlet 23A and is formed inside the main body 21A in a substantially U shape so as to surround the anode cylinder 10. And reaches the exit 23B.

  As for the 1st accommodating part 24, 24A of inner surfaces which are curved surfaces contact the anode cylinder 10 (refer Fig.2 (a)).

  The main body 21A has a first tightening portion 22A on one side surface thereof. After the cooling block 20 is mounted on the anode cylinder 10, the first inner surface 24 </ b> A of the first housing portion 24, which is a curved surface, is housed in the first housing portion 24 by tightening the first screw screw 22 </ b> B of the first tightening portion 22 </ b> A. The anode cylinder 10 is contacted and fixed (see FIG. 2A). Therefore, the main body 21A can cool the anode cylinder 10 efficiently.

  In addition, each of the four first screw holes 22C is continuous with each of the four second screw holes 26D provided in the magnet contact portion 21B on the opposing surface 27A of the main body portion 21A facing the magnet contact portion 21B. It is provided as follows. The first screw hole 22C receives a third screw 26C for fixing the magnet contact portion 21B to the main body portion 21A. The first screw hole 22C is provided so as to avoid the cooling liquid circulation pipe 23.

  The facing surface 27 </ b> A that faces the magnet contact portion 21 </ b> B is a surface that is substantially perpendicular to the inner surface 24 </ b> A of the first housing portion 24.

  The facing surface 27A of the main body 21A facing the magnet contact portion 21B is in contact with the upper surface 28B of the magnet contact portion 21B. Therefore, the main body portion 21A and the magnet contact portion 21B can be in thermal contact.

  The magnet contact portion 21B, which is a separate body from the main body portion 21A, has substantially the same shape, but is smaller than the main body portion 21A. The magnet contact portion 21B has a second housing portion 25 for housing the annular permanent magnet 8A (or 8B) therein. As described above, the magnet contact portion 21B serves as a connection portion that connects the main body portion 21A and the annular permanent magnets 8A and 8B when viewed from the main body portion 21A.

  As for the 2nd accommodating part 25, 25A of inner surfaces which are curved surfaces contact with the annular permanent magnet 8A (or 8B) (refer Fig.2 (a)).

  Further, the magnet contact portion 21B has a second tightening portion 26A on one side surface thereof. After the main body portion 21A is brought into contact with and fixed to the anode cylinder 10, the second screw 26B of the second tightening portion 26A is tightened so that the inner surface 25A of the second housing portion 25 which is a curved surface is inside the second housing portion 25. The ring-shaped permanent magnets 8A and 8B accommodated in the magnet are contacted and fixed. Therefore, the magnet contact portion 21B can efficiently cool the annular permanent magnets 8A and 8B.

  The upper surface 28B of the magnet contact portion 21B is in contact with the facing surface 27A of the main body portion 21A. Therefore, the magnet contact portion 21B and the main body portion 21A can be in thermal contact.

  Further, the magnet contact portion 21B is fastened to the main body portion 21A with four third screws 26C. The screw hole 26D and the screw hole 22C that receive the third screw 26C have a slightly larger diameter than the diameter of the third screw 26C, and have a play. Therefore, when the magnet contact portion 21B contacts the annular permanent magnet 8A (or 8B), even if the magnet contact portion 21B is displaced with respect to the main body portion 21A, the magnet contact portion 21B is provided with the four third screws 26C. The main body 21A can be securely fastened.

  As described above, in magnetron 1 according to the present embodiment, magnet contact portion 21B is provided separately from main body portion 21A. This is because the magnet contact portion 21B can be contacted and fixed to the annular permanent magnets 8A and 8B even after the main body portion 21A is contacted and fixed to the anode cylinder 10. Therefore, in the conventional example, when the cooling block is positioned with respect to the anode cylinder, there is a slight gap between the permanent magnet and the permanent magnet. However, in the magnetron 1 according to the present embodiment, the main body portion Even after positioning by contacting and fixing 21A to the anode cylinder 10, the magnet contact portion 21B can be contacted and fixed to the annular permanent magnets 8A and 8B.

  Therefore, in the magnetron 1 according to the present embodiment, the cooling block 20 has a constant cooling performance for the annular permanent magnets 8A and 8B and does not vary. Furthermore, in the magnetron 1 according to the present embodiment, each magnet contact portion 21B is smaller than the main body portion 21A, so that an increase in the size of the cooling block 20 can be avoided.

  In magnetron 1 concerning this embodiment, although main part 21A and magnet contact part 21B of cooling block 20 are aluminum, it is not restricted to this. Any metal having good thermal conductivity may be used. For example, metals such as the above-described aluminum and aluminum alloy, copper and copper alloy may be combined.

  A heat conductive paste may be applied between the inner surface 25A of the second housing portion 25 and the annular permanent magnets 8A and 8B in order to improve the thermal connection.

  A heat conductive paste may be applied between the facing surface 27A of the main body 21A and the upper surface 28B of the magnet contact portion 21B in order to improve thermal connection.

  Note that a heat diffusion compound may be applied to a slight gap between the outer wall surface of the main body 21 </ b> A and the inner wall surface of the magnetic yoke 4. Even if there is a gap in the contact portion, a good heat conduction state is obtained, and both are fixed at the contact portion. Therefore, the cooling block 20 includes not only the anode cylinder 10 and the annular permanent magnets 8A and 8B, but also the annular permanent magnets 8A and 8B and the filter 11 indirectly via the magnetic yoke 4 and the magnetic yoke 4. Can be cooled.

(Modification 1)
Next, with reference to FIGS. 3A, 3B, and 4, Modification 1 of the cooling block 20 in the magnetron 1 according to the present embodiment will be described. FIG. 3A is a plan view of the cooling block 40, and FIG. 3B is a side view of the cooling block 40. FIG. 4 is a perspective view of the magnet contact piece 41B. In addition, about the part which is common in the cooling block 20, the same code | symbol is quoted and the detailed description is abbreviate | omitted. The cooling block 40 shown in FIGS. 3A and 3B includes a main body portion 41A and a plurality of magnet contact pieces 41B.

  Here, when viewed from the main body portion 41A, the plurality of small magnet contact pieces 41B serve as connection portions that connect the main body portion 41A and the annular permanent magnets 8A and 8B.

  Further, the main body portion 41 </ b> A comes into contact with the anode cylinder 10 to mainly cool the anode cylinder 10. On the other hand, the plurality of small magnet contact pieces 41B can be said to be connected portions when viewed from the main body portion 41A, but have a function of cooling the annular permanent magnets 8A and 8B. Therefore, the main body 41A and the plurality of small magnet contact pieces 41B constituting the cooling block 40 function as a cooling member.

  The main body portion 41 </ b> A includes a first housing portion 24 that houses the anode cylinder 10 and a cooling liquid circulation pipe 23 therein. In FIG. 4A, as indicated by a one-dot chain line, the cooling liquid circulation conduit 23 is formed in the main body portion 21A in a substantially U shape so as to extend from the inlet 23A and surround the anode cylinder 10. And reaches the exit 23B.

  Further, the main body portion 41A has a first tightening portion 22A on one side surface thereof, and after the cooling block 20 is mounted on the anode cylinder 10, the first screw 22B of the first tightening portion 22A is tightened. The anode cylinder 10 accommodated in the one accommodating part 24 is contacted and fixed. Therefore, the main body portion 41A can cool the anode cylinder 10 efficiently.

  Further, ten fourth screw holes 42C are provided on the surface of the main body 41A facing the magnet contact piece 41B so as to be continuous with the third screw holes 46D provided in the magnet contact piece 41B. . The fourth screw hole 42C receives a fourth screw 46C for fixing each magnet contact piece 41B to the main body 41A. The fourth screw hole 42 </ b> C is provided to avoid the cooling liquid circulation conduit 23.

  In FIG. 3 (b), only the fourth screw 46C, the fourth screw hole 42C, and the third screw hole 46D are illustrated for explanation, but in actuality, for each magnet contact piece 41B, FIG. Each is provided.

  Next, the magnet contact piece 41B will be described with reference to FIGS. 3 (a), 3 (b), and 4. FIG. As shown in FIG. 4, the magnet contact piece 41B includes a horizontal portion 43 fixed to the main body portion 41A, and a rising portion that extends from one end of the horizontal portion 43 in a substantially vertical direction and contacts the annular permanent magnets 8A and 8B. 44.

  The rising portion 44 has one surface 44 </ b> A that is substantially perpendicular to the horizontal portion 43. The one surface 44A may have a certain curvature so as to contact the outer peripheral surfaces of the annular permanent magnets 8A and 8B.

  The horizontal portion 43 has a third screw hole 46 </ b> D that penetrates the horizontal portion 43. As described above, the third screw hole 46D is provided for screwing the fourth screw 46C. Further, the third screw hole 46D is formed into a long hole as shown in FIG. 4, and the long axis direction of the third screw hole 46D (the direction of the arrow X in the figure) is an annular permanent magnet 8A, 8B. Coincides with the radial direction. Therefore, after the main body portion 41A is fastened to the anode cylinder 10 accommodated in the first housing portion 24, when the magnet contact piece 41B is fastened to the main body portion 41A with the fourth screw 46C, the third screw hole 46D Along the long axis direction (in other words, the radial direction of the annular permanent magnets 8A and 8B), the position of the magnet contact piece 41B relative to the main body portion 41A can be adjusted so as to contact the annular permanent magnets 8A and 8B. it can. Therefore, one surface 44A of the rising portion 44 is surely in contact with the annular permanent magnets 8A and 8B.

  Next, the attachment position of the magnet contact piece 41B will be described with reference to FIGS. 3 (a) and 3 (b).

  As shown in FIG. 3A, the magnet contact pieces 41B are arranged at equal intervals along the outer peripheral surface of the annular permanent magnet 8A (or 8B), and one surface 44A of the rising portion 44 is annular permanent. The fourth screw 46C is fastened to the upper surface (or lower surface) of the main body portion 41A so as to contact the magnet 8A (or 8B).

  Here, the third screw hole 46D, which receives the fourth screw 46C, is subjected to a long hole process so as to have some play. Therefore, even if each magnet contact piece 41B is slightly displaced with respect to the main body portion 41A when contacting the annular permanent magnets 8A, 8B, each magnet contact piece 41B is the main body portion 41A with the fourth screw 46C. It is fastened to the upper surface (or the lower surface).

  As described above, in the magnetron 1 according to the present embodiment, the plurality of small magnet contact pieces 41B are provided separately from the main body portion 41A. This is because each magnet contact piece 41B is easily positioned and brought into contact with the annular permanent magnet 8A (or 8B) even after the main body portion 41A is positioned on the anode cylinder 10. Therefore, for example, in the conventional example, when the cooling block is positioned with respect to the anode cylinder, a slight gap is generated between the permanent magnet and the permanent magnet, but in the magnetron 1 according to the present embodiment, Even after positioning the main body 41A on the anode cylinder 10, the magnet contact pieces 41B can be easily positioned and brought into contact with the annular permanent magnets 8A and 8B.

  The cooling block 40 is made of aluminum, but is not limited thereto. For example, you may make with an aluminum alloy, copper, and a copper alloy.

  In addition, although the main-body part 41A and the magnet contact small piece 41B of the cooling block 40 are the metals which have the same high heat conductivity, it is not restricted to this. For example, you may combine metals, such as the aluminum and aluminum alloy mentioned above, copper, and a copper alloy.

  Note that the heat diffusion compound may be applied to a slight gap between the outer wall surface of the main body 41A and the inner wall surface of the magnetic yoke 4. Even if there is a gap in the contact portion, a good heat conduction state is obtained, and both are fixed at the contact portion. Therefore, the cooling block 40 includes not only the anode cylinder 10 and the annular permanent magnets 8A and 8B, but also the annular permanent magnets 8A and 8B and the filter 11 indirectly via the magnetic yoke 4 and the magnetic yoke 4. Can be cooled.

  In the cooling block 40, each magnet contact piece 41B is individually screwed to the main body portion 41A, but an annular magnet contact portion 61B shown in FIG. 5 may be used instead of the magnet contact piece 41B. FIG. 5 is a perspective view of the annular magnet contact portion 61B.

  Here, like the magnet contact piece 41B, the annular magnet contact portion 61B serves as a connection portion that connects the main body portion 41A and the annular permanent magnets 8A and 8B.

  Further, the main body portion 41 </ b> A comes into contact with the anode cylinder 10 to mainly cool the anode cylinder 10. On the other hand, the annular magnet contact portion 61B can be said to be a connecting portion when viewed from the main body portion 41A, but has a function of cooling the annular permanent magnets 8A and 8B. Therefore, the main body portion 41A and the annular magnet contact portion 61B constituting the cooling block 40 function as a cooling member.

  As shown in FIG. 5, the annular magnet contact portion 61 </ b> B has a horizontal portion 63 and an annular rising portion 64 that rises from the horizontal portion 63 in a substantially vertical direction.

  The annular magnet contact portion 61B is brought into contact with the outer peripheral surface of the annular permanent magnets 8A and 8B and the inner peripheral surface 64A, which is a curved surface thereof, by tightening the third tightening portion 62A with the fifth screw 62B.

  The horizontal parts 63 are arranged at equal intervals on the outer periphery of the annular rising part 64. The horizontal portion 63 has a third screw hole 46D for fastening the annular magnet contact portion 61B to the main body portion 41A.

  Note that the magnet contact portion 21B, the plurality of small magnet contact pieces 41B, and the annular magnet contact portion 61B that function as connection portions may be molded members of insulating resin having high thermal conductivity. For example, a material such as a filler can be considered.

  The magnet contact portion 21B may be sandwiched between the magnetic yoke 4b and the main body portion 21A.

  In addition, in order to tighten the first screw 22B of the first tightening portion 22A or to tighten the third tightening portion 62A with the fifth screw 62B, a hole for inserting a driver is provided in the magnetic yokes 4a and 4b for the number of fixed members. May be.

  Note that a heat conductive sheet or a fibrous metal may be used instead of the heat conductive paste.

  The magnetron and microwave utilization device according to the present invention has an effect of efficiently cooling the anode cylinder and the permanent magnet, and avoiding an increase in size of the cooling member itself while suppressing variation in the cooling performance for the permanent magnet, Useful as a microwave oven.

DESCRIPTION OF SYMBOLS 1 Magnetron 4 Magnetic yoke 8A, 8B Annular permanent magnet 10 Anode cylinder 20, 40 Cooling block 21A Main part 21B Magnet contact part 24 First accommodating part 25 Second accommodating part 41A Main part 41B Magnet contact small piece 61B Annular magnet Contact part 63 Horizontal part 64 Rising part

Claims (9)

An anode cylinder;
Permanent magnets provided at both ends of the anode cylinder,
A magnetic yoke that houses the anode cylinder and the permanent magnet therein;
A cooling member accommodated in the anode cylinder, at least a part of which is fixed to the anode cylinder;
A connecting portion disposed between the magnetic yoke and the cooling member;
Magnetron equipped with. The connecting portion is
Bringing the permanent magnet into contact with the cooling member;
The magnetron according to claim 1. The connecting portion is
The inner surface is in contact with the permanent magnet,
Fixed to the cooling member at a surface substantially perpendicular to the inner surface;
The magnetron according to claim 2. The connecting portion is
One of copper and copper alloy, aluminum and aluminum alloy,
The magnetron according to any one of claims 1 to 3. The connection part is a plurality of magnet contact pieces disposed along an outer peripheral surface of the permanent magnet that is annular, and the magnet contact pieces are:
A horizontal portion fixed to the cooling member;
A rising portion that is continuous with the horizontal portion and has one surface that contacts the outer peripheral surface of the permanent magnet;
The magnetron according to claim 1. The connecting portion is disposed along an outer peripheral surface of the permanent magnet that is annular.
The connecting portion includes a plurality of horizontal portions fixed to the cooling member, and a rising portion having one surface that is continuous with the plurality of horizontal portions and contacts an outer peripheral surface of the permanent magnet.
The magnetron according to claim 1. The connecting portion is a molded member of an insulating resin having high thermal conductivity.
The magnetron according to claim 1, claim 5, or claim 6. A heat conductive paste is applied between the connection portion and the permanent magnet, and / or the connection portion and the cooling member,
The magnetron according to claim 7.   A microwave utilization apparatus provided with the magnetron of any one of Claims 1-8.

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