JP6316160B2 - Magnetron - Google Patents

Description

  The present invention relates to a magnetron, and is suitable for application to a continuous wave magnetron used in microwave heating equipment such as a microwave oven.

  A general magnetron for microwave ovens that oscillates radio waves in the 2450 MHz band has an oscillation unit, an input unit, and an output unit. The oscillating unit, the input unit, and the output unit are provided along the tube axis that is the central axis of the magnetron. That is, the input unit is provided on one end side in the tube axis direction of the oscillation unit, and the output unit is provided on the other end side.

  The oscillation part has an anode part and a cathode part. The anode portion has an anode cylinder and a plurality of vanes protruding from the inner peripheral surface of the anode cylinder toward the central tube axis. The cathode part has a spiral cathode (cathode), an input side end hat and an output side end hat, a cathode center lead, and a cathode side lead.

  The spiral cathode is provided on the tube axis, the input side end hat is provided at one end of the spiral cathode in the tube axis direction (end on the input side), and the output side end hat is the other end in the tube axis direction of the spiral cathode. (End on the output side). The cathode center lead extends in the tube axis direction through the inside of the spiral cathode, and is electrically connected to the spiral cathode via an output-side end hat provided at the other end of the spiral cathode. On the other hand, the cathode side lead is electrically connected to the spiral cathode via an input side end hat provided at the other end of the spiral cathode (see, for example, Patent Document 1).

  Conventionally, when assembling such a cathode part, a part for supporting the output side end hat, which is a cylindrical end hat chip having an inner diameter larger than the outer diameter of the cathode center lead, is connected to the output side of the cathode center lead. The end portion is inserted and the end hat tip and the cathode center lead are fixed by laser welding. Further, the cathode center lead and the end hat tip are fixed by pouring a brazing material into the gap between the cathode center lead and the end hat tip and solidifying it.

  Next, the end on the output side of the spiral cathode is fixed to the outer periphery of the end hat chip by the brazing material, and the input side end of the spiral cathode is fixed to the input side end hat by the brazing material.

  After that, insert the output side end hat of the cathode center lead into the output side end hat having a hole larger than the outer diameter of the cathode center lead and smaller than the outer diameter of the end hat tip, and the output side end hat is then inserted into the end hat. It abuts on the tip and is fixed to the cathode center lead by laser welding.

JP 2013-206568 A

  By the way, in laser welding when fixing the end hat tip to the cathode center lead, the cathode center lead and the end hat tip are welded at several points one by one. The center axis may be displaced, or the center axis of the end hat tip may be inclined with respect to the center axis of the cathode center lead.

  In addition to supporting the output-side end hat, the end-hat chip also plays a role of fixing the output-side end of the spiral cathode, so the center axis of the end-hat chip is displaced from the center axis of the cathode center lead. If this happens, the central axis of the spiral cathode will also shift.

  In addition, if the center axis of the end hat tip is fixed while being tilted with respect to the center axis of the cathode center lead, then, when the output side end hat is fixed to the cathode center lead, the end hat tip abuts. Therefore, there is a possibility that the center axis of the output side end hat to be laser-welded is also inclined with respect to the center axis of the cathode center lead.

  In fact, if the center axis of the cathode center lead is shifted from the center axis of the spiral cathode or the center axis of the output end hat is tilted with respect to the center axis of the cathode center lead, the magnetron The characteristics will vary.

  Therefore, the present invention has been made to solve the above-described problems, and an object of the present invention is to reduce variations in the characteristics of magnetrons as compared with the prior art.

  In order to achieve the above object, a magnetron according to the present invention includes a cylindrical anode cylinder extending along a central axis from the input side toward the output side, and extends from the inner surface of the anode cylinder toward the central axis. A plurality of vanes whose free ends form a vane inscribed circle; a cathode disposed along the central axis in a vane inscribed circle formed by the free ends of the plurality of vanes; and an inner side of the cathode A cathode center lead extending along the central axis, an end hat chip provided at an output side end of the cathode center lead and connected to an output side end of the cathode, and the end of the cathode center lead An output side end hat provided on the output side from the hat tip and connected to the cathode via the end hat tip, and an input side end of the cathode center lead. The end hat tip has a through-hole penetrating from the input-side end to the output-side end, and extends in the depth direction of the through-hole on the inner wall of the through-hole. A protruding portion protruding inward is formed, and the cathode center lead is press-fitted into the through hole.

  According to the present invention, the laser welding when the end hat tip is fixed to the cathode center lead is omitted, the center axis of the cathode center lead and the center axis of the end hat tip are shifted, or the center axis of the cathode center lead is Thus, the end hat tip can be press-fitted and fixed to the cathode center lead without tilting the center axis of the end hat tip, so that variations in the characteristics of the magnetron can be reduced.

1 is an overall longitudinal sectional view of a magnetron according to a first embodiment of the present invention. It is a side view which shows the structure of the cathode part of the magnetron which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the output side end hat periphery of the magnetron which concerns on the 1st Embodiment of this invention, and the structure of an end hat chip. It is a figure which shows the structure of the output side end hat periphery of the magnetron which concerns on the 2nd Embodiment of this invention, and the structure of an end hat chip. It is a figure which shows the structure of the output side end hat periphery of the magnetron which concerns on the 3rd Embodiment of this invention, and the structure of an end hat chip. It is a figure which shows the structure of the output side end hat of the magnetron which concerns on the 4th Embodiment of this invention. It is a figure which shows the structure of the output side end hat periphery of the magnetron which concerns on the 4th Embodiment of this invention, and the structure of an end hat chip.

  An embodiment of a magnetron according to the present invention will be described with reference to the drawings. The following embodiment is merely an example, and the present invention is not limited to this.

[First Embodiment]
First, the first embodiment will be described. FIG. 1 is a longitudinal sectional view showing an outline of a magnetron 1 of the present embodiment. The magnetron 1 is a magnetron for a microwave oven that generates a fundamental wave in the 2450 MHz band. The magnetron 1 includes an oscillating unit 2 that generates a fundamental wave in the 2450 MHz band, an input unit 4 that supplies power to a cathode 3 located at the center of the oscillating unit 2, and a microwave oscillated from the oscillating unit 2 outside the tube (magnetron 1 The output unit 5 is taken out to the outside. The oscillating unit 2, the input unit 4, and the output unit 5 are provided along the tube axis m that is the central axis of the magnetron 1. That is, the input unit 4 is provided on one end side (lower side in the drawing) of the oscillation unit 2 in the tube axis direction, and the output unit 5 is provided on the other end side (upper side in the drawing).

  The input unit 4 and the output unit 5 are joined to the oscillating unit 2 in a vacuum secret by an input-side metal sealing body 6 and an output-side metal sealing body 7, respectively.

  The oscillation part 2 has an anode part 8 and a cathode part 9. The anode part 8 has an anode cylinder 10 and a plurality of (for example, 10) vanes 11. The anode cylinder 10 is made of, for example, copper and is formed in a cylindrical shape, and the central axis thereof is disposed so as to pass through the tube axis m that is the central axis of the magnetron 1.

  Each vane 11 is made of, for example, copper, is formed in a plate shape, and is arranged radially around the tube axis m inside the anode cylinder 10. The outer end of each vane 11 is joined to the inner peripheral surface of the anode cylinder 10, and the inner end is a free end. A cylindrical space surrounded by the free ends of the plurality of vanes 11 is an electron action space.

  The cathode portion 9 includes a cathode 3, two end hats 12 and 13, a cathode center lead 14, and a cathode side lead 15. The cathode 3 is a spiral cathode made of tungsten or the like, and is provided on the tube axis m of the electron action space. The cathode 3 is disposed at a distance from the free ends of the plurality of vanes 11.

  End hats 12 and 13 for preventing electrons from jumping out are fixed to an input side end (lower end) and an output end (upper end) of the cathode 3, respectively. An input-side end hat (referred to as an input-side end hat) 12 is formed in a ring shape, and an output-side end hat (referred to as an output-side end hat) 13 is formed on a disk.

  The cathode center lead 14 is planted on the ceramic stem 16 of the input unit 4, extends in the tube axis m direction through the inside of the cathode 3, and is provided on the output side end hat provided at the output side end of the cathode 3. It is electrically connected to the cathode 3 through 13. On the other hand, the cathode side lead 15 is also planted on the ceramic stem 16 of the input unit 4 and is electrically connected to the cathode 3 via the input side end hat 12 provided at the input side end of the cathode 3. ing.

  Further, the oscillating unit 2 includes a pair of pole pieces 17 and 18 inside the input side end (lower end) and the output side end (upper end) of the anode cylinder 10, respectively. Oppositely provided so as to sandwich a space between the hat 12 and the output side end hat 13.

  The input side pole piece (referred to as an input side pole piece) 17 is provided with a through-hole having a diameter slightly larger than that of the input-side end hat 12 at the center thereof. It is formed in a substantially funnel shape that expands toward the side (downward). The input side pole piece 17 is arranged so that the tube axis m passes through the center of the through hole.

  On the other hand, the output-side pole piece (referred to as an output-side pole piece) 18 is provided with a through-hole having a slightly larger diameter than the output-side end hat 13 at the center thereof. It is formed in a substantially funnel shape that spreads toward the output side (upward). The output side pole piece 18 is arranged so that the tube axis m passes through the center of the through hole.

  Further, the upper end portion of the substantially cylindrical metal sealing body 6 extending in the tube axis m direction is fixed to the outer peripheral portion of the input side pole piece 17. The metal sealing body 6 is also in contact with the lower end portion of the anode cylinder 10. On the other hand, the lower end portion of the substantially cylindrical metal sealing body 7 extending in the tube axis m direction is fixed to the output side pole piece 18 at the outer peripheral portion. The metal sealing body 7 is also in contact with the upper end portion of the anode cylinder 10.

  A ceramic stem 16 constituting the input unit 4 is joined to the lower end of the input side metal sealing body 6. That is, the cathode center lead 14 and the cathode side lead 15 planted on the ceramic stem 16 are connected to the cathode 3 through the inside of the metal sealing body 6.

  On the other hand, the output side metal sealing body 7 has an insulating cylinder 19 constituting the output section 5 joined to the upper end thereof, and an exhaust pipe 20 joined to the upper end of the insulating cylinder 19. Furthermore, the antenna 21 led out from one of the plurality of vanes 11 passes through the output side pole piece 18, extends to the upper end side through the inside of the metal sealing body 7, and the tip is the exhaust pipe 20. It is clamped and fixed to.

  A pair of ring-shaped magnets 22 and 23 are provided on the outside of the metal sealing bodies 6 and 7 so as to sandwich the anode cylinder 10 in the tube axis m direction. The pair of magnets 22 and 23 generate a magnetic field in the tube axis m direction.

  Further, the anode cylinder 10 and the magnets 22 and 23 are covered by a yoke 24, and a magnetic circuit is formed by the pair of magnets 22 and 23 and the yoke 24. Then, the magnetic flux from the magnets 22 and 23 of this magnetic circuit is guided to the electron action space between the free end of the vane 11 and the cathode 3 by the input side pole piece 17 and the output side pole piece 18. ing.

  Further, a radiator 25 is provided between the anode cylinder 10 and the yoke 24, and heat generated by the oscillation of the oscillating unit 2 is released to the outside of the magnetron 1. The cathode 3 is connected to a filter circuit 26 having a coil and a feedthrough capacitor via a cathode center lead 14 and a cathode side lead 15. The filter circuit 26 is housed in a filter box 27. The outline of the configuration of the magnetron 1 is as described above.

  Next, the configuration of the cathode portion 9 will be described in more detail with reference to FIGS. FIG. 2 is a side view showing the entire cathode portion 9, and only the left side in the drawing is a cross-sectional view. FIG. 3A is a side view of the periphery of the output-side end hat 13, and only the left side in the drawing is a cross-sectional view. FIG. 3B is a side view and an AA cross-sectional view of an end hat chip 30 to be described later.

  As shown in FIGS. 2 and 3, the cathode portion 9 includes a cathode center lead 14 that extends in the tube axis m direction through the inside of the cathode 3 through the hole in the center of the input side end hat 12 of the cathode 3. Yes. A cylindrical end hat tip 30 having an inner diameter L2 larger than the outer diameter L1 of the cathode center lead 14 is inserted and fixed at the output side end of the cathode center lead 14. The end hat chip 30 is a component for supporting the output side end hat 13 and fixing the output side end portion of the cathode 3. The cathode center lead 14 and the end hat chip 30 are both made of molybdenum, which is a refractory metal, for example.

  The output end hat 13 has a through hole 13A having a diameter larger than the outer diameter L1 of the cathode center lead 14 and smaller than the outer diameter of the end hat chip 30, and the cathode center lead 14 is provided in the through hole 13A. The output side end portion is inserted and fixed in contact with the output side end portion of the end hat chip 30.

  Further, the outer diameter of the end hat tip 30 is substantially equal to the inner diameter of the cathode 3, and the cathode 3 is fixed to the outside of the end hat tip 30 so that the end portion on the output side of the cathode 3 is wound. . That is, the cathode center lead 14 is electrically connected to the cathode 3 through the end hat chip 30.

  On the other hand, the cathode side lead 15 (see FIG. 1) is joined to the input side end hat 12 of the cathode 3 and is electrically connected to the cathode 3 through the input side end hat 12. A current is supplied from the input unit 4 to the cathode 3 through the cathode center lead 14 and the cathode side lead 15.

  Here, the end hat chip 30 will be described in more detail. As shown in FIG. 3, the end hat tip 30 has a cylindrical shape and includes a through hole 31 having a substantially circular cross section passing through the central axis. The central axis of the through hole 31 coincides with the central axis of the end hat tip 30. Furthermore, ring-shaped dents 32 that extend outside the through holes 31 are formed on both end faces of the end hat tip 30.

  In addition, a protrusion 33 protruding toward the central axis is formed on the inner wall of the through hole 31. The protrusion 33 has a substantially triangular cross section, and extends in the depth direction from one end side to the other end side of the inner wall of the through hole 31. Three identical protrusions 33 are provided on the inner wall of the through hole 31 at equal intervals in the circumferential direction.

  The through hole 31 has a diameter of an inner wall (that is, an inner diameter) L2 that is larger than an outer diameter L1 of the cathode center lead 14 and passes through the tips of the three protrusions 33 (this is called a protrusion inscribed circle). (Omitted in the figure) is formed to be smaller than the outer diameter L1 of the cathode center lead 14. Therefore, when the cathode center lead 14 is inserted into the through hole 31 of the end hat chip 30, the tip of the protrusion 33 comes into contact with the outer periphery of the cathode center lead 14.

  Here, the assembly method of the cathode part 9 is demonstrated. First, the output side end of the cathode center lead 14 is inserted into the through hole 31 of the end hat chip 30.

  Specifically, since the diameter of the protrusion inscribed circle of the end hat tip 30 is smaller than the outer diameter L 1 of the cathode center lead 14, the cathode center lead 14 is press-fitted into the end hat tip 30. Here, assuming that the cathode center lead 14 and the end hat chip 30 have the same hardness, the tip of the protrusion 33 of the end hat chip 30 is deformed so as to be pressed against the outer periphery of the cathode center lead 14 and crushed.

  When the end hat tip 30 reaches a predetermined position on the output side of the cathode center lead 14, the press-fitting is finished. At this time, since the outer periphery of the cathode center lead 14 presses the tip of the protrusion 33 of the end hat chip 30, the protrusion 33 of the end hat chip 30 and the outer periphery of the cathode center lead 14 are in contact with each other. The cathode center lead 14 and the end hat chip 30 are fixed.

  At this time, the end hat tip 30 is still temporarily fixed to the cathode center lead 14. For example, when the position of the end hat tip 30 is not correct, the position of the end hat tip 30 is appropriately moved. Be able to.

  When the end hat chip 30 is temporarily fixed in this manner, the brazing material is then poured from the recess 32 of the end hat chip 30 into the gap between the through hole 31 of the end hat chip 30 and the outer periphery of the cathode center lead 14. By solidifying, the cathode center lead 14 and the end hat tip 30 are fixed. At this point, the position of the end hat tip 30 is determined and is completely fixed.

  Next, the end on the output side of the cathode 3 is inserted into the outer periphery of the end hat chip 30 and is fixed by the brazing material, and the input side end of the cathode 3 is fixed to the input side end hat 12 by the brazing material.

  Thereafter, the output-side end portion of the cathode center lead 14 is inserted into the through hole 13A of the output-side end hat 13, and the output-side end hat 13 and the output-side end surface of the end-hat chip 30 are brought into contact with each other. The output side end hat 13 is fixed to the cathode center lead 14 by welding. The cathode portion 9 can be assembled by such an assembling method.

  As described so far, in the first embodiment, three protrusions 33 extending in the depth direction of the through hole 31 are provided on the inner wall of the through hole 31 of the end hat chip 30. The end hat tip 30 can be fixed to the cathode center lead 14 simply by press-fitting the cathode center lead 14 into the through hole 31 of the end hat tip 30.

  By doing so, the laser welding for fixing the end hat tip 30 to the cathode center lead 14, which has been conventionally required, is omitted, and the projection 33 of the through hole 31 and the cathode center lead 14 are laser welded. The center axis of the cathode center lead 14 and the center axis of the end hat chip 30 may be misaligned or the cathode center may be contacted by a line (or surface) parallel to the depth direction of the through hole 31 instead of the point contact by The cathode center lead 14 and the end hat tip 30 can be fixed without the center axis of the end hat tip 30 being inclined with respect to the center axis of the lead 14. Thus, according to the first embodiment, variations in the characteristics of the magnetron 1 can be reduced.

  In addition, according to the first embodiment, the end hat tip 30 can be fixed to the cathode center lead 14 by press-fitting rather than laser welding, so that the working efficiency during assembly is increased, and as a result, the magnetron 1 Manufacturing costs can also be reduced.

[Second Embodiment]
Next, a second embodiment will be described. The second embodiment differs from the first embodiment only in the configuration of the end hat chip. Therefore, here, the configuration of the end hat chip will be mainly described.

  FIG. 4 shows the configuration around the output end hat 13 and the configuration of the end hat chip 100 of the second embodiment. 4A is a side view of the periphery of the output end hat 13, and only the left side in the drawing is a cross-sectional view. FIG. 4B is a side view and a B-B cross-sectional view of the end hat chip 100. In FIG. 4A, the same parts as those in the first embodiment are denoted by the same reference numerals.

  The end hat tip 100 is cylindrical and has a through hole 101 having a substantially elliptical cross section passing through the central axis. Furthermore, ring-shaped depressions 102 that extend outside the through holes 101 are formed on both end faces of the end hat chip 100.

  In addition, a protrusion 103 that protrudes toward the central axis is formed on the inner wall of the through hole 101. The protrusion 103 has a substantially triangular cross section, and extends in the depth direction from one end side to the other end side of the inner wall of the through hole 101. One protrusion 103 is provided on the inner wall of the through hole 101.

  In the end hat chip 100, when the cathode center lead 14 is inserted into the through hole 101, the protrusion 103 and the inner wall of the through hole 101 facing the protrusion 103 come into contact with the outer periphery of the cathode center lead 14. The shape of the through hole 101 is selected.

  That is, the diameter L3 of the through hole 101 is larger than the outer diameter L1 of the cathode center lead 14, and the distance L4 between the tip of the protrusion 103 and the inner wall facing the tip 103 is smaller than the outer diameter L1 of the cathode center lead 14. ing.

  In addition, the end hat chip 100 has a center axis of the end hat chip 100 and a center axis of the cathode center lead 14 when the cathode center lead 14 is press-fitted into the through hole 101 and the protrusion 103 is crushed and deformed. The center point (not shown in the figure) of the distance L4 between the tip of the projection 103 and the inner wall facing this is shifted from the central axis of the end hat chip 100 toward the facing inner wall. .

  By doing so, the end hat chip 100 has only one protrusion 103, but when the cathode center lead 14 is press-fitted into the through hole 101, the center axis of the end hat chip 100 and the center of the cathode center lead 14 are the same. The axis can be matched. The assembling method is the same as that of the first embodiment.

  As described so far, in the second embodiment, one protrusion 103 extending in the depth direction of the through hole 101 is provided on the inner wall of the through hole 101 of the end hat chip 100, and when this is press-fitted, One protrusion 103 and the inner wall of the through hole 101 opposed to the protrusion 103 are in contact with the outer periphery of the cathode center lead 14.

  By doing so, similarly to the first embodiment, the laser welding when fixing the end hat tip 100 to the cathode center lead 14 is omitted, and the protrusion 103 of the through hole 101 and the inner wall facing the protrusion 103, Since the cathode center lead 14 can be brought into contact with a line (or surface) parallel to the depth direction of the through-hole 101 rather than a point contact by laser welding, the center axis of the cathode center lead 14 and the end hat tip 100 can be contacted. Thus, the cathode center lead 14 and the end hat chip 100 can be fixed without causing the center axis of the cathode hat to shift or the center axis of the end hat chip 100 to be inclined with respect to the center axis of the cathode center lead 14. Thus, as in the first embodiment, variations in the characteristics of the magnetron 1 can be reduced.

  Further, the end hat chip 100 of the second embodiment has a smaller number of protrusions 103 than that of the first embodiment. In fact, if the number of the protrusions 103 is large, the pressure required for press-fitting increases accordingly, the work efficiency during assembly deteriorates, and the manufacturing cost of the magnetron 1 increases. Therefore, in the second embodiment, the number of the protrusions 103 of the end hat chip 100 is smaller than that in the first embodiment. Thereby, compared with 1st Embodiment, the working efficiency at the time of an assembly raises further, and the manufacturing cost of the magnetron 1 can further be reduced.

[Third Embodiment]
Next, a third embodiment will be described. The third embodiment differs from the first embodiment only in the configuration of the end hat chip and the output side end hat. Therefore, here, the configuration of the end hat chip and the output side end hat will be mainly described.

  FIG. 5 shows the configuration around the output end hat 200 and the configuration of the end hat chip 210 of the third embodiment. FIG. 5A is a side view of the periphery of the output end hat 200, and only the left side in the drawing is a cross-sectional view. FIG. 5B is a side view and a top view of the end hat chip 210. In FIG. 5A, the same parts as those in the first embodiment are denoted by the same reference numerals.

  The output-side end hat 200 has a through-hole 200A having a diameter L6 that is larger than an outer diameter L5 of a protruding portion 212 of the end hat tip 210, which will be described later, and smaller than an outer diameter of the main body portion 211 of the end hat tip 210. .

  On the other hand, the end hat chip 210 has a cylindrical main body 211 that has substantially the same shape as the end hat chip 30 of the first embodiment, and a main body 211 that protrudes from the end face on the output side of the main body 211. It is comprised with the cylindrical protrusion part 212 with a small outer diameter. The central axis of the protruding part 212 coincides with the central axis of the main body part 211. Further, a through hole 213 having a substantially circular cross section passing through the central axis is formed from the input side end surface of the main body 211 to the output side end surface of the protrusion 212. Furthermore, a ring-shaped recess 214 that extends to the outside of the through hole 213 is formed on the input-side end face of the main body 211 as in the first embodiment.

  Furthermore, a projection (referred to as an inner projection) 215 that protrudes toward the central axis is formed on the inner wall of the through hole 213. The inner protrusion 215 has a substantially triangular cross section, and extends in the depth direction from one end side to the other end side of the inner wall of the through hole 213. Three inner protrusions 215 are provided on the inner wall of the through hole 213 at equal intervals in the circumferential direction.

  In addition, a protruding portion (referred to as an outer protruding portion) 216 that protrudes outward is formed on the outer wall of the protruding portion 212. The outer protrusion 216 also has a substantially triangular cross section and extends from one end side to the other end side of the outer wall of the protrusion 212. Three outer projections 216 are provided on the outer wall of the protruding portion 212 at equal intervals in the circumferential direction. Note that the three outer protrusions 216 and the three inner protrusions 215 are provided at positions adjacent to each other on the outer side and the inner side of the through hole 213, for example.

  The protrusion 212 has a diameter (not shown) of a circle passing through the tips of the three outer protrusions 216 (referred to as a protrusion circumscribed circle) larger than the diameter L6 of the through hole 200A of the output end hat 200. It is formed to become.

  Here, a method for assembling the cathode portion 9 according to the third embodiment will be described. First, the output side end of the cathode center lead 14 is press-fitted into the through hole 213 of the end hat chip 210. When the end hat chip 210 reaches a predetermined position on the output side of the cathode center lead 14, the press-fitting is finished. At this time, the outer periphery of the cathode center lead 14 presses the tip of the inner protrusion 215 of the end hat chip 210 so that the inner protrusion 215 of the end hat chip 210 and the outer periphery of the cathode center lead 14 are in contact with each other. Therefore, the cathode center lead 14 and the end hat chip 210 are fixed.

  Next, the cathode center lead 14 and the end hat chip 210 are fixed by pouring a brazing material into a gap between the through hole 213 of the end hat chip 210 and the outer periphery of the cathode center lead 14 to solidify.

  Next, the end on the output side of the cathode 3 is inserted into the outer periphery of the end hat chip 210 and fixed by the brazing material, and the input side end of the cathode 3 is fixed to the input side end hat 12 by the brazing material. The assembly method so far is the same as that of the first embodiment.

  Thereafter, the output side end portion of the cathode center lead 14 is inserted into the through hole 200A of the output side end hat 200, and the protruding portion 212 of the end hat chip 210 is press-fitted into the through hole 200A of the output side end hat 200. .

  At this time, since the diameter of the protrusion circumscribed circle of the end hat tip 210 is smaller than the diameter L6 of the through hole 200A of the output side end hat 200, the tip of the outer protrusion 216 of the end hat tip 210 is at the end of the output side end hat 200. The inner wall of the through hole 200A is deformed so as to be crushed by being pressed. At this time, the inner wall of the through hole 200A of the output side end hat 200 is pressed against the tip of the outer protrusion 216 of the end hat chip 210 so that the outer protrusion 216 of the end hat chip 210 and the output side end hat 200 are pressed. Since the inner wall of the through hole 200A is in contact, the output side end hat 200 and the end hat tip 210 are fixed.

  Thereafter, the output end hat 200 is fixed to the end hat tip 210 by, for example, laser welding. The cathode portion 9 of the third embodiment can be assembled by such an assembling method.

  As described so far, in the third embodiment, three outer protrusions 216 extending in the central axis direction are provided on the outer wall of the protrusion 212 protruding from the output-side end face of the end hat chip 210. The output side end hat 200 and the end hat chip 210 are fixed by press-fitting the protrusion 212 into the through hole 200 </ b> A of the output side end hat 200.

  By doing so, the inner wall of the through hole 200A of the output side end hat 200 and the outer protrusion 216 of the end hat chip 210 can be brought into contact with each other by a line (or surface) parallel to the depth direction of the through hole 200A. Therefore, the center axis of the output-side end hat 200 and the center axis of the end-hat chip 210 are not shifted, and the center axis of the end-hat chip 210 is not inclined with respect to the center axis of the output-side end hat 200. Laser welding can be performed with the output side end hat 200 and the end hat tip 210 fixed. Thus, as in the first embodiment, the variation in the characteristics of the magnetron 1 can be further reduced as compared with the case where the output side end hat 13 is brought into contact with the end hat tip 30 and laser welding is performed. .

[Fourth Embodiment]
Next, a fourth embodiment will be described. The fourth embodiment differs from the first embodiment only in the configuration of the end hat chip and the output side end hat. Therefore, here, the configuration of the end hat chip and the output side end hat will be mainly described.

  6 and 7 show the configuration of the output end hat 300, the configuration around the output end hat 300, and the configuration of the end hat chip 310 according to the fourth embodiment. FIG. 6A is a bottom view of the output-side end hat 300 as viewed from the lower side (input side). FIG. 6B is a side view of the output-side end hat 300, and only the left side in the drawing is a cross-sectional view. FIG. 7A is a side view of the periphery of the output end hat 300, and only the left side in the drawing is a cross-sectional view. FIG. 7B is a side view and a top view of the end hat chip 310. In FIG. 7A, the same parts as those in the first embodiment are denoted by the same reference numerals.

  The output-side end hat 300 is formed with a cylindrical protruding portion 301 that protrudes toward the input side at the center thereof. The central axis of the protrusion 301 coincides with the central axis of the output side end hat 300. The protrusion 301 has a through hole 302 that is larger than the outer diameter L1 of the cathode center lead 14 and has the same diameter as a through hole 311 of an end hat chip 310 to be described later.

  Further, a projection 303 that protrudes toward the central axis is formed on the inner wall of the through hole 302. The protrusion 303 has a substantially triangular cross section and extends in the depth direction from one end side to the other end side of the inner wall of the through hole 302. Three identical protrusions 303 are provided on the inner wall of the through hole 302 at equal intervals in the circumferential direction.

  The through hole 302 has an inner wall diameter (that is, inner diameter) L7 larger than the outer diameter L1 of the cathode center lead 14 and the diameter of a protrusion inscribed circle passing through the tips of the three protrusion portions 303 (not shown). The cathode center lead 14 is formed to be smaller than the outer diameter L1. Therefore, when the cathode center lead 14 is inserted into the through hole 302 of the output side end hat 300, the tip of the protrusion 303 comes into contact with the outer periphery of the cathode center lead 14.

  On the other hand, the end hat tip 310 is cylindrical and has a through hole 311 having a substantially circular cross section passing through the central axis. The through hole 311 has a central axis that coincides with the central axis of the end hat tip 310. Furthermore, a ring-shaped recess 312 that extends to the outside of the through hole 311 is formed on the end face on the input side of the end hat chip 310 as in the first embodiment. On the other hand, the end face on the output side of the end hat chip 310 is formed in a ring shape extending outside the through-hole 311, and a recess 313 deeper than the recess 312 is formed. The concave portion 313 is a portion into which the protruding portion 301 of the output side end hat 300 is fitted, and has an inner diameter L9 that is larger than the outer diameter L8 of the protruding portion 301.

  Furthermore, three protrusions 314 similar to the protrusions 33 of the first embodiment are formed on the inner wall of the through hole 311 at equal intervals in the circumferential direction.

  Here, a method of assembling the cathode portion 9 according to the fourth embodiment will be described. First, the output side end of the cathode center lead 14 is press-fitted into the through hole 311 of the end hat chip 310. When the end hat chip 310 reaches a predetermined position on the output side of the cathode center lead 14, the press-fitting is finished. At this time, since the outer periphery of the cathode center lead 14 presses the tip of the protrusion 314 of the end hat chip 310, the protrusion 314 of the end hat chip 310 and the outer periphery of the cathode center lead 14 are in contact with each other. The cathode center lead 14 and the end hat chip 310 are fixed.

  Next, the cathode center lead 14 and the end hat tip 310 are fixed by pouring a brazing material into a gap between the through hole 311 of the end hat tip 310 and the outer periphery of the cathode center lead 14 to solidify.

  Next, the end on the output side of the cathode 3 is inserted into the outer periphery of the end hat chip 310 and fixed with a brazing material, and the input side end of the cathode 3 is fixed to the input side end hat 12 with a brazing material. The assembly method so far is the same as that of the first embodiment.

  Thereafter, the output-side end portion of the cathode center lead 14 is press-fitted into the through hole 302 of the output-side end hat 300, and the protruding portion 301 of the output-side end hat 300 is fitted into the recess 313 of the end-hat chip 310.

  At this time, since the diameter of the protrusion inscribed circle of the output side end hat 300 is smaller than the outer diameter L 1 of the cathode center lead 14, the tip of the protruding portion 303 of the output side end hat 300 is pressed against the outer periphery of the cathode center lead 14. It is deformed to be crushed. At this time, the outer periphery of the cathode center lead 14 presses the tip of the protrusion 303 of the output side end hat 300 so that the protrusion 303 of the output end hat 300 and the outer periphery of the cathode center lead 14 come into contact with each other. Therefore, the output side end hat 300 and the cathode center lead 14 are fixed.

  Thereafter, the output side end hat 300 is fixed to the cathode center lead 14 by, for example, laser welding. The cathode portion 9 of the fourth embodiment can be assembled by such an assembling method.

  As described so far, in the fourth embodiment, three protrusions 303 extending in the depth direction are provided on the inner wall of the through-hole 302 of the output-side end hat 300, and a cathode is provided in the through-hole 302. The cathode center lead 14 and the output side end hat 300 were fixed by press-fitting the center lead 14.

  By doing so, the inner wall of the through hole 302 of the output side end hat 300 and the outer periphery of the cathode center lead 14 can be brought into contact with a line (or surface) parallel to the depth direction of the through hole 302. The center axis of the output side end hat 300 and the center axis of the cathode center lead 14 are not shifted, and the center axis of the cathode center lead 14 is not inclined with respect to the center axis of the output side end hat 300. Laser welding can be performed with the hat 300 and the cathode center lead 14 fixed. Thus, the variation in the characteristics of the magnetron 1 can be further reduced as compared with the case where the output side end hat 13 is brought into contact with the end hat tip 30 and laser welding is performed as in the first embodiment.

[Other embodiments]
The first to fourth embodiments described above are examples. For example, in the third and fourth embodiments described above, the number of protrusions 215, 216, 303, and 314 is three as in the first embodiment, but the present invention is not limited to this. Similarly to the second embodiment, the number of the projections 215, 216, 303, and 314 may be one. In the third embodiment described above, the number of the inner protrusions 215 and the outer protrusions 216 are both three. However, the present invention is not limited to this, and one of these is not limited to the second embodiment. It is good also as one like. Similarly, in the fourth embodiment, one of the protrusions 303 and 314 may be set to one as in the second embodiment.

  Furthermore, the number of the protrusions 33, 103, 215, 216, 303, and 314 is not limited to one or three, but may be two or four or more. Furthermore, in the first embodiment, the shape of the protrusion 33 is a triangular cross section. However, the shape is not limited to this, and the protrusion 33 may have a substantially trapezoidal cross section or a substantially triangular cross section with a rounded tip. Good. The same applies to the second to fourth embodiments.

  Furthermore, in 1st Embodiment mentioned above, although the projection part 33 of the end hat chip 30 extended from the one end side of the through-hole 31 to the other end side, it is not restricted to this, The depth of the through-hole 31 As long as it extends in the direction (that is, the direction of the central axis of the end hat tip 30), it does not necessarily have to extend from one end side to the other end side. The same applies to the second to fourth embodiments.

  Furthermore, in the first embodiment described above, the protrusion 33 of the end hat chip 30 extends linearly in the central axis direction of the end hat chip 30, but this is not a limitation, for example, in the central axis direction. It may extend spirally. The same applies to the second to fourth embodiments.

  Furthermore, in the fourth embodiment described above, the cylindrical protrusion 301 protruding to the input side is formed at the center of the output end hat 300. However, the present invention is not limited to this, and the protrusion 301 is not limited thereto. Instead of this, a protruding portion that protrudes toward the output side of the output side end hat 300 may be formed.

  DESCRIPTION OF SYMBOLS 1 ... Magnetron, 2 ... Oscillation part, 3 ... Cathode, 4 ... Input part, 5 ... Output part, 8 ... Anode part, 9 ... Cathode part, 10 ... Anode cylinder, 11 ... Bain, 12 …… Input side end hat, 13 …… Output side end hat, 14 …… Cathode center lead, 15 …… Cathode side lead, 30, 100, 210, 310 …… End hat chip, 31, 101, 213, 302 311... Through-holes, 33, 103, 215, 216, 303, 314... Projections, 211.

Claims (5)

A cylindrical anode cylinder extending along the central axis from the input side toward the output side;
A plurality of vanes extending from the inner surface of the anode cylinder toward the central axis, the free ends forming a vane inscribed circle;
A cathode disposed along the central axis in a vane inscribed circle formed by the free ends of the plurality of vanes;
A cathode center lead passing through the inside of the cathode and extending along the central axis;
An end hat chip provided at an output side end of the cathode center lead and connected to an output side end of the cathode;
An output side end hat provided on the output side of the cathode center lead from the end hat chip, and connected to the cathode via the end hat chip;
An input side end hat connected to the input side end of the cathode center lead;
The end hat chip is
A through hole penetrating from the input side end to the output side end, and a protrusion projecting inward and extending in the depth direction of the through hole is formed on the inner wall of the through hole; A magnetron with a center lead press-fitted. Three protrusions are provided at equal intervals in the circumferential direction on the inner wall of the through hole, and the cathode is inserted into the through hole with the tips of the three protrusions in contact with the outer periphery of the cathode center lead. The magnetron according to claim 1, wherein a center lead is press-fitted. One protrusion is provided on the inner wall of the through-hole, and the tip of the protrusion and the inner wall facing the protrusion are in contact with the outer periphery of the cathode center lead. The magnetron according to claim 1, wherein the cathode center lead is press-fitted. The end hat tip consists of a cylindrical main body part and a cylindrical projecting part protruding from the output side end of the main body part and having an outer diameter smaller than the outer diameter of the main body part,
The through hole penetrates from the input side end of the main body part to the output side end of the protrusion,
Furthermore, the outer wall of the protrusion is formed with a protrusion that extends in the depth direction of the through hole and protrudes outwardly.
The magnetron according to any one of claims 1 to 3, wherein the protruding portion of the end hat tip is press-fitted into a through hole formed in the output side end hat. The output end hat is
A through hole penetrating from the input side end to the output side end, and a protrusion projecting inward and extending in the depth direction of the through hole is formed on the inner wall of the through hole; The magnetron according to any one of claims 1 to 3, wherein a center lead is press-fitted.

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