Technical Field
[0001] The present invention relates to a magnetron that is suitable for use in microwave
oscillation apparatus such as microwave-using apparatus.
Background Art
[0002] Magnetrons are roughly divided into a vacuum tube part and an exterior part. The
vacuum tube part includes an anode cylinder whose inner wall surface is provided with
a plurality of vanes extending radially, an input unit having a cathode structure
disposed on the center axis of the anode cylinder, and a high-frequency wave output
unit. The exterior part is includes permanent magnets, magnetic yokes which constitute
a magnetic circuit, and a cooling unit.
[0003] There are various methods for positioning the vacuum tube part and the exterior part
with respect to each other. For example, in the magnetron disclosed in Patent Document
1, as shown in Fig. 10, annular ribs 31 project from the inner surface of a first
magnetic yoke 3 which is disposed on the high-frequency wave output side. As shown
in Fig. 9, a positioning plate 4 whose outer diameter matches the inner diameter of
the annular ribs 31 so that the positioning plate 4 is just fitted in the annular
ribs 31 and whose inner diameter matches the outer diameter of the high-frequency
wave output unit so that the positioning plate 4 is just fitted with a high-frequency
wave output unit is sandwiched between the first magnetic yoke 3 and a permanent magnet
122. The vacuum tube part and the exterior part are positioned with respect to and
fixed to each other by the positioning plate 4 interposed in between by fitting the
positioning plate 4 into the annular ribs 31 and with the high-frequency wave output
unit 111.
[0004] In Patent Document 1, shown in Fig. 9, a cooling unit has a spiral structure and
the positioning plate has baffle plates 41 so as to obstruct a cooling wind flowing
through ineffective air passages.
Related Art Documents
Patent Documents
Summary of the Invention
Problem to be Solved by the Invention
[0006] However, in the above conventional configuration, since the yoke is formed with the
ribs, the rib projection height has a limit and assembling is possible even in a state
that the positioning plate 4 is not fitted in the annular ribs 31.
[0007] Furthermore, with the structure that the positioning plate 4 has the baffle plates
41, directivity occurs at the time of assembling. As a result, assembling is complicated
and a probability is high that the positioning plate 4 goes up onto the annular ribs
31.
[0008] Still further, the ribs which are formed on the yoke have only the function of positioning
and fixing the vacuum tube part and the exterior part with respect to each other by
the positioning plate 4 interposed in between; no consideration is given to positioning
with respect to a waveguide unit of a microwave-using apparatus or the like.
[0009] Therefore, where only general attachment screws are used, the position of the magnetron
relative to the waveguide unit varies, raising a problem that discharge may occur
between the high-frequency wave output unit and the waveguide unit.
[0010] The present invention has been made in the above circumstances, and an object of
the present invention is to provide a magnetron high-frequency wave output unit can
be positioned with respect to and fixed to its magnetic yoke and the waveguide unit
of a microwave-using apparatus or the like reliably, without complicating its structure
or assembling method.
Means for Solving the Problem
[0011] To solve the above problems in the related art, the invention provides a magnetron
including: an anode cylinder including a high-frequency wave output unit; permanent
magnets disposed on two opposite sides of the anode cylinder, respectively; and a
magnetic yoke which houses therein the anode cylinder and the permanent magnets, wherein
a portion, on a high-frequency wave output side, of the magnetic yoke is formed with
a plurality of cut and raised parts, and a metal plate which matches the high-frequency
wave output unit and the cut and raised parts is sandwiched between one of the permanent
magnet and the magnetic yoke, whereby the anode cylinder and the magnetic yoke are
positioned with respect to and fixed to each other.
[0012] With this configuration, the high-frequency wave output unit of the magnetron can
reliably be positioned with respect to and fixed to the magnetic yoke and a waveguide
unit of a microwave-using apparatus or the like, without complicating its structure
or assembling method.
[0013] In the above magnetron, a waveguide unit, to which the magnetron is attached, of
a microwave-using apparatus is formed with a cut and raised part which matches a hole
formed by the cut and raised part in the magnetic yoke, and the cut and raised part
of the waveguide unit is fitted in the hole of the magnetic yoke, whereby the magnetic
yoke and the waveguide unit are positioned with respect to and fixed to each other.
[0014] In the above magnetron, a waveguide unit, to which the magnetron is attached, of
a microwave-using apparatus is formed with a projection which matches a hole formed
by the cut and raised part in the magnetic yoke, and the projection of the waveguide
unit is fitted in the hole of the magnetic yoke, whereby the magnetic yoke and the
waveguide unit are positioned with respect to and fixed to each other.
[0015] In the above magnetron, a waveguide unit, to which the magnetron is attached, of
a microwave-using apparatus is formed with a hole which matches the cut and raised
part of the magnetic yoke, and the cut and raised part of the magnetic yoke is fitted
in the hole of the waveguide unit, whereby the magnetic yoke and the waveguide unit
are positioned with respect to and fixed to each other.
[0016] With the above structures, the height of the cut and raised parts can be set freely
and hence deviation of the positioning metal plate can be suppressed.
[0017] Since the plurality of cut and raised parts are formed, the positioning metal plate
need not have directivity and is given a simple structure, which facilitates assembling.
[0018] The magnetic yoke and the waveguide unit are positioned with respect to and fixed
to each other because of the structure that the cut and raised parts formed in the
magnetic yoke are fitted in the respective holes formed in the waveguide unit or the
cut and raised parts or the projections formed in the waveguide unit of the microwave-using
apparatus are fitted in the respective holes formed by the cut and raised parts in
the magnetic yoke. As a result, the high-frequency output unit and the waveguide unit
are positioned with respect to and fixed to each other, whereby discharge between
the high-frequency output unit and the waveguide unit can be suppressed.
[0019] The invention also provides a magnetron including: an anode cylinder including a
high-frequency wave output unit; permanent magnets disposed on two opposite sides
of the anode cylinder, respectively; and a magnetic yoke which houses therein the
anode cylinder and the permanent magnets, wherein a portion, on a high-frequency wave
output side, of the magnetic yoke is formed with a plurality of holes, a metal plate
which matches the high-frequency wave output unit and the holes is sandwiched between
one of the permanent magnet and the magnetic yoke, and positioning rods are inserted
in the respective holes, whereby the anode cylinder and the magnetic yoke are positioned
with respect to and fixed to each other.
[0020] In the above magnetron, a waveguide unit, to which the magnetron is attached, of
a microwave-using apparatus is formed with holes which match the respective holes
of the magnetic yoke, and the magnetic yoke and the waveguide unit are positioned
with respect to and fixed to each other by the positioning rods.
[0021] With the above structures, the positioning rods can be set freely and hence deviation
between the positioning metal plate and the magnetic yoke can be suppressed.
[0022] Since the positioning rods are inserted in the respective holes, the positioning
metal plate need not have directivity and is given a simple structure, which facilitates
assembling.
[0023] The metal plate, the magnetic yoke, and the waveguide unit are positioned with respect
to and fixed to each other by the positioning rods. As a result, the high-frequency
output unit and the waveguide unit are positioned with respect to and fixed to each
other, whereby discharge between the high-frequency output unit and the waveguide
unit can be suppressed.
[0024] By applying the above-described magnetron to a microwave-using apparatus, the microwave-using
apparatus with can be more stable and enhanced in performance.
Advantages of the Invention
[0025] The magnetron and the microwave-using apparatus according to the invention make it
possible to reliably positioning and fixing the high-frequency wave output unit of
the magnetron with respect to and to a magnetic yoke of the magnetron and the waveguide
unit of a microwave-using apparatus or the like, without complicating their structures
or assembling methods.
Brief Description of the Drawings
[0026]
Fig. 1 is a front view of a magnetron according to a first embodiment of the present
invention.
Fig. 2 is a perspective view of a magnetic yoke and a metal plate of the magnetron
according to the first embodiment of the invention.
Fig. 3 is a partially sectional view of a magnetron with a waveguide unit according
to the first embodiment of the invention.
Fig. 4 is a perspective view of a magnetic yoke of a magnetron according to a second
embodiment of the invention.
Fig. 5 is a partially sectional view of a magnetron with a waveguide unit according
to the second embodiment of the invention.
Fig. 6 is a front view of a magnetron according to a third embodiment of the invention.
Fig. 7 is a perspective view of a rod of the magnetron according to the third embodiment
of the invention.
Fig. 8 is a partially sectional view of a magnetron with a waveguide unit according
to the third embodiment of the invention.
Fig. 9 is a front view of a conventional magnetron.
Fig. 10 is a perspective view of a magnetic yoke and a positioning plate of the conventional
magnetron.
Mode for Carrying Out the invention
[0027] A first invention provides a magnetron including: an anode cylinder including a high-frequency
wave output unit; permanent magnets disposed on two opposite sides of the anode cylinder,
respectively; and a magnetic yoke which houses therein the anode cylinder and the
permanent magnets, wherein a portion, on a high-frequency wave output side, of the
magnetic yoke is formed with a plurality of cut and raised parts, and a metal plate
which matches the high-frequency wave output unit and the cut and raised parts is
sandwiched between one of the permanent magnet and the magnetic yoke, whereby the
anode cylinder and the magnetic yoke are positioned with respect to and fixed to each
other. With this configuration, the high-frequency wave output unit of the magnetron
can reliably be positioned with respect to and fixed to the magnetic yoke and a waveguide
unit of a microwave-using apparatus, without complicating its structure or assembling
method, and the assembling can be facilitated by the simplified structure.
[0028] A second invention provides the magnetron of the first invention, particularly, wherein
a waveguide unit, to which the magnetron is attached, of a microwave-using apparatus
is formed with a cut and raised part which matches a hole formed by the cut and raised
part in the magnetic yoke, and the cut and raised part of the waveguide unit is fitted
in the hole of the magnetic yoke, whereby the magnetic yoke and the waveguide unit
are positioned with respect to and fixed to each other. With this configuration, a
variation in a relative position of the high-frequency wave output unit and the waveguide
unit can be suppressed, and occurrence of discharge between the high-frequency wave
output unit and the waveguide unit can be suppressed.
[0029] A third invention provides the magnetron of the first invention, particularly, wherein
a waveguide unit, to which the magnetron is attached, of a microwave-using apparatus
is formed with a projection which matches a hole formed by the cut and raised part
in the magnetic yoke, and the projection of the waveguide unit is fitted in the hole
of the magnetic yoke, whereby the magnetic yoke and the waveguide unit are positioned
with respect to and fixed to each other. With this configuration, a variation in a
relative position of the high-frequency wave output unit and the waveguide unit can
be suppressed, and occurrence of discharge between the high-frequency wave output
unit and the waveguide unit can be suppressed.
[0030] A fourth invention provides the magnetron of the first invention, particularly, wherein
a waveguide unit, to which the magnetron is attached, of a microwave-using apparatus
is formed with a hole which matches the cut and raised part of the magnetic yoke,
and the cut and raised part of the magnetic yoke is fitted in the hole of the waveguide
unit, whereby the magnetic yoke and the waveguide unit are positioned with respect
to and fixed to each other. With this configuration, a variation in a relative position
of the high-frequency wave output unit and the waveguide unit can be suppressed, and
occurrence of discharge between the high-frequency wave output unit and the waveguide
unit can be suppressed.
[0031] A fifth invention provides a magnetron including: an anode cylinder including a high-frequency
wave output unit; permanent magnets disposed on two opposite sides of the anode cylinder,
respectively; and a magnetic yoke which houses therein the anode cylinder and the
permanent magnets, wherein a portion, on a high-frequency wave output side, of the
magnetic yoke is formed with a plurality of holes, a metal plate which matches the
high-frequency wave output unit and the holes is sandwiched between one of the permanent
magnet and the magnetic yoke, and positioning rods are inserted in the respective
holes, whereby the anode cylinder and the magnetic yoke are positioned with respect
to and fixed to each other. With this configuration, the high-frequency wave output
unit of the magnetron can reliably be positioned with respect to and fixed to the
magnetic yoke and a waveguide unit of a microwave-using apparatus, without complicating
its structure or assembling method, and the assembling can be facilitated by the simplified
structure.
[0032] A sixth invention provides the magnetron of the fifth invention, particularly, wherein
a waveguide unit, to which the magnetron is attached, of a microwave-using apparatus
is formed with holes which match the respective holes of the magnetic yoke, and the
magnetic yoke and the waveguide unit are positioned with respect to and fixed to each
other by the positioning rods. With this configuration, a variation in a relative
position of the high-frequency wave output unit and the waveguide unit can be suppressed,
and occurrence of discharge between the high-frequency wave output unit and the waveguide
unit can be suppressed.
[0033] A seventh invention provides a microwave-using apparatus including the magnetron
according to any one of the first to sixth inventions, which can be more stable and
enhanced in performance
[0034] Embodiments of the invention will be hereinafter described with reference to the
drawings. The embodiments should not be construed as restricting the invention.
(Embodiment 1)
[0035] Fig. 1 is a front view of a magnetron according to a first embodiment of the invention.
Fig. 2 is a perspective view of a magnetic yoke and a metal plate of the magnetron
according to the first embodiment of the invention.
[0036] As shown in Fig. 1, the magnetron 1 includes a vacuum tube part 11 and an exterior
part 12. The vacuum tube part 11 includes an anode cylinder 112, an input unit (not
shown), and a high-frequency wave output unit 111. The exterior part includes permanent
magnets 122, magnetic yokes 121 which constitute a magnetic circuit, a cooling unit
123 including a plurality of cooling fins, and a filter unit 124 for supplying power
to the input unit.
[0037] The magnetic yokes 121 includes a first magnetic yoke 1211 disposed on the high-frequency
wave output side and a second magnetic yoke 1212 disposed on the filter side which
are connected to each other by caulking.
[0038] A metal plate 125 is as thick as about 30% of the magnetic yokes 121, and is sandwiched
between the permanent magnet 122 and the first magnetic yoke 1211. A gasket 126 is
held and leakage of radio waves to be are output from the high-frequency wave output
unit 111 is prevented.
[0039] As shown in Fig. 2, the first magnetic yoke 1211 is formed with four cut and raised
parts 1213 having a height that is about three times the thickness of the magnetic
yokes 121 at ineffective air passage portions of a cooling wind so as to project toward
the inside of the magnetic yokes and to be arranged radially and symmetrically so
as to have no directivity. The cut and raised parts 1213 are formed so as to just
fit with the metal plate 125 whose outer diameter is approximately equal to the diameter
of the circle that inscribes their end faces.
[0040] The metal plate 125 is formed in such a manner that its inner diameter of the is
approximately equal to the outer diameter of the high-frequency wave output unit 111
of the vacuum tube part 11 so that the metal plate 125 just fits with the high-frequency
wave output unit 111.
[0041] With the above structures, the vacuum tube part 11 is positioned with respect to
the first magnetic yoke 1211 with the metal plate 125 interposed in between because
an inside portion (in the radial direction) of the metal plate 125 is fitted with
the high-frequency wave output unit 111 and an outside portion (in the radial direction)
of the metal plate 125 is fitted in the circle that inscribes the end faces of the
cut and raised parts 1213 of the first magnetic yoke 1211.
[0042] The first magnetic yoke 1211 has holes 1214 as a result of the formation of the respective
cut and raised parts 1213.
[0043] Fig. 3 is a partially sectional view of a magnetron with a waveguide unit according
to the first embodiment of the invention.
[0044] As shown in Fig. 3, a portion, to which the magnetron 1 is to be attached, of a waveguide
unit 2 is formed with four cut and raised parts 21 having a height that is about two
times the thickness of the magnetic yokes 121 at such positions as to fit into the
respective holes 1214 formed by the cut and raised parts 1213 of the first magnetic
yoke 1211 so as to project toward the outside of the waveguide unit 2. The cut and
raised parts 21 of the waveguide unit 2 are partially fitted in the respective holes
1214 formed by the cut and raised parts 1213 of the first magnetic yoke 1211.
[0045] With this structure, the magnetron 1 and the waveguide unit 2 are positioned with
respect to each other and the first magnetic yoke 1211 and the waveguide unit 2 are
fixed to each other with screws.
[0046] How the above-configured magnetron works will be described below.
[0047] First, shaped like a disc, the metal plate 125 has no directivity and enables simple
assembling. Since the height of the cut and raised parts 1213 is sufficiently greater
than the thickness of the metal plate 125, the metal plate 125 never goes up onto
the cut and raised parts 1213.
[0048] Since the vacuum tube part 11 of the magnetron 1 is positioned with respect to the
first magnetic yoke 1211 with the metal plate 125 interposed in between, positional
variations of members involved can be reduced at the time of assembling and deviations
can be suppressed when the magnetron 1 is subjected to vibration or impact.
[0049] Furthermore, since the magnetron 1 is positioned with respect to and fixed to the
waveguide unit 2, deviations of the high-frequency wave output unit 111 with respect
to the waveguide unit 2 can be suppressed to a large extent, whereby the occurrence
of discharge between the high-frequency wave output unit 111 and the waveguide unit
2 can be suppressed and radio waves can be guided reliably.
[0050] Still further, since the cut and raised parts 1213 are formed at ineffective air
passage portions of a cooling wind, they also serve as baffle plates, making it possible
to apply a cooling wind to the cooling fins efficiently.
[0051] After hitting the cut and raised parts 1213, parts of a cooling wind flow through
the holes 1214 formed by the cut and raised parts 1213 and flow into the waveguide
unit through the holes 22 formed by the cut and raised parts 21 of the waveguide unit
2, to produce a convectional air flow in the waveguide unit. It is therefore expected
that the occurrence of discharge between the high-frequency wave output unit 111 and
the waveguide unit 2 can be suppressed further.
[0052] It is preferable that an even number of cut and raised parts be arranged symmetrically
so as not to have directivity. However, the number, size, positions, shape, directions,
and angle of the cut and raised parts are not restricted at all as long as they enable
positioning with respect to the metal plate and the waveguide unit.
[0053] The cut and raised parts for positioning of the metal plate and those for positioning
of the waveguide unit may be formed separately.
[0054] Although it is preferable that the metal plate have such a simple structure as not
to have directivity, the metal plate may have any structure as long as it can be positioned
with respect to the yokes.
(Embodiment 2)
[0055] Fig. 4 is a perspective view of a magnetic yoke of a magnetron according to a second
embodiment of the invention. Fig. 5 is a partially sectional view of a magnetron with
a waveguide unit according to the same embodiment.
[0056] As shown in Fig. 4, a first magnetic yoke 1215 is formed with four first cut and
raised parts 1216 having a height that is about three times the thickness of the magnetic
yokes at ineffective air passage portions of a cooling wind so as to project toward
the inside of the magnetic yokes and to be arranged radially and symmetrically so
as to have no directivity. The first cut and raised parts 1216 are formed so as to
just fit with the metal plate 125 whose outer diameter is approximately equal to the
diameter of the circle that inscribes their end faces.
[0057] The first magnetic yoke 1215 is formed with two second cut and raised parts 1217
having a height that is about two times the thickness of the magnetic yokes so as
to project toward the outside of the magnetic yokes and to be arranged radially and
symmetrically so as to have no directivity.
[0058] The first magnetic yoke 1215 has holes 1214 as a result of the formation of the respective
first cut and raised parts 1216.
[0059] The magnetron is configured in the same manner as in the first embodiment except
for the first magnetic yoke 1215.
[0060] With the above structures, the vacuum tube part 11 is positioned with respect to
the first magnetic yoke 1215 with the metal plate 125 interposed in between because
an inside portion (in the radial direction) of the metal plate 125 is fitted with
the high-frequency wave output unit 111 and an outside portion (in the radial direction)
of the metal plate 125 is fitted in the circle that inscribes the end faces of the
cut and raised parts 1215 of the first magnetic yoke 1215.
[0061] As shown in Fig. 5, a portion, to which the magnetron 1 is to be attached, of the
waveguide unit 2 is formed with first holes 23 at such positions as to be fitted with
the respective second cut and raised parts 1217 of the first magnetic yoke 1215.
[0062] Furthermore, the portion, to which the magnetron 1 is to be attached, of the waveguide
unit 2 is formed with second holes 24 at the same positions as the respective holes
1214 formed by the first cut and raised parts 1216 of the first magnetic yoke 1215.
The second cut and raised parts 1217 of the first magnetic yoke 1215 are partially
fitted in the respective first holes 23 of the waveguide unit 2.
[0063] With this structure, the magnetron 1 and the waveguide unit 2 are positioned with
respect to each other and the first magnetic yoke 1215 and the waveguide unit 2 are
fixed to each other with screws.
[0064] How the above-configured magnetron works will be described below.
[0065] First, shaped like a disc, the metal plate 125 has no directivity and enables simple
assembling.
[0066] Since the height of the first cut and raised parts 1216 is sufficiently greater than
the thickness of the metal plate 125, the metal plate 125 never goes up onto the first
cut and raised parts 1216.
[0067] Since the vacuum tube part 11 of the magnetron 1 is positioned with respect to the
first magnetic yoke 1215 with the metal plate 125 interposed in between, positional
variations of members involved can be reduced at the time of assembling and deviations
can be suppressed when the magnetron 1 is subjected to vibration or impact.
[0068] Furthermore, since the magnetron 1 is positioned with respect to and fixed to the
waveguide unit 2, deviations of the high-frequency wave output unit 111 with respect
to the waveguide unit 2 can be suppressed to a large extent, whereby the occurrence
of discharge between the high-frequency wave output unit 111 and the waveguide unit
2 can be suppressed and radio waves can be guided reliably.
[0069] Still further, since the first cut and raised parts 1216 are formed at ineffective
air passage portions of a cooling wind, they also serve as baffle plates, making it
possible to apply a cooling wind to the cooling fins efficiently.
[0070] After hitting the first cut and raised parts 1216, parts of a cooling wind flow through
the holes 1214 formed by the first cut and raised parts 1216 and flow into the waveguide
unit through the second holes 24 of the waveguide unit 2, to produce a convectional
air flow in the waveguide unit. It is therefore expected that the occurrence of discharge
between the high-frequency wave output unit 111 and the waveguide unit 2 can be suppressed
further.
[0071] It is preferable that an even number of cut and raised parts be arranged symmetrically
so as not to have directivity. However, the number, size, positions, shape, directions,
and angle of the cut and raised parts are not restricted at all as long as they enable
positioning with respect to the metal plate and the waveguide unit.
[0072] Although it is preferable that the metal plate have such a simple structure as not
to have directivity, it may have any structure as long as it can be positioned with
respect to the yokes.
[0073] It is preferable that for the purpose of air convention the waveguide unit 2 be formed
with holes other than those for the relative positioning. However, the number, positions,
and shape of the holes are not restricted at all as long as they make it possible
to position the waveguide unit with respect to the magnetron.
(Embodiment 3)
[0074] Fig. 6 is a front view of a magnetron according to a third embodiment of the invention.
Fig. 7 is a perspective view of a rod of the magnetron according to the third embodiment
of the invention.
[0075] As shown in Fig. 6, a first magnetic yoke 1218 is formed with four holes 1219 approximately
on the outer circumference of the metal plate 125 at ineffective air passage portions
of a cooling wind so as to be arranged radially and symmetrically so as to have no
directivity.
[0076] Rods 127 are inserted through the four respective holes 1219 of the first magnetic
yoke 1218 so as to project by approximately the same length inward and outward.
[0077] As shown in Fig. 7, each rod 127 has a semicylindrical shape and has a length that
is about five times the thickness of the magnetic yokes. The rods 127 are press-fitted
in the respective holes 1219 of the first magnetic yoke 1218.
[0078] The rods 127 are made of aluminum.
[0079] The metal plate 125 is fitted in the circle that inscribes the circular arcs of the
four rods 127, and is thereby positioned with respect to the first magnetic yoke 1218.
[0080] The magnetron is configured in the same manner as in the first embodiment except
for the first magnetic yoke 1218 and the rods 127.
[0081] With the above structures, the vacuum tube part 11 is positioned with respect to
the first magnetic yoke 1218 with the metal plate 125 interposed in between because
an inside portion (in the radial direction) of the metal plate 125 is fitted with
the high-frequency wave output unit 111 and an outside portion (in the radial direction)
of the metal plate 125 is fitted in the circle that inscribes the circular arcs of
the rods 127 which are press-fitted in the first magnetic yoke 1218.
[0082] Fig. 8 is a partially sectional view of a magnetron with a waveguide unit according
to the third embodiment of the invention.
[0083] As shown in Fig. 8, a portion, to which the magnetron 1 is to be attached, of the
waveguide unit 2 is formed with holes 25 at such positions as to fit with the respective
rods 127 which are press-fitted in the first magnetic yoke 1218. The rods 127 are
fitted in the respective holes 25 of the waveguide unit 2.
[0084] With this structure, the magnetron 1 and the waveguide unit 2 are positioned with
respect to each other and the first magnetic yoke 1215 and the waveguide unit 2 are
fixed to each other with screws.
[0085] How the above-configured magnetron works will be described below.
[0086] First, shaped like a disc, the metal plate 125 has no directivity and enables simple
assembling. Since the height of the rods 127 is sufficiently greater than the thickness
of the metal plate 125, the metal plate 125 never goes up onto the rods 127.
[0087] Since the rods 127 are not magnetic, the magnetic loss can be suppressed. Since the
vacuum tube part 11 of the magnetron 1 is positioned with respect to the first magnetic
yoke 1218 via the metal plate 125 and the rods 127, positional variations of members
involved can be reduced at the time of assembling and deviations can be suppressed
when the magnetron 1 is subjected to vibration or impact.
[0088] Furthermore, since the magnetron 1 is positioned with respect to and fixed to the
waveguide unit 2, deviations of the high-frequency wave output unit 111 with respect
to the waveguide unit 2 can be suppressed to a large extent, whereby the occurrence
of discharge between the high-frequency wave output unit 111 and the waveguide unit
2 can be suppressed and radio waves can be guided reliably.
[0089] Still further, since the rods 127 project at ineffective air passage portions of
a cooling wind, they also serve as baffle plates, making it possible to apply a cooling
wind to the cooling fins efficiently.
[0090] What is more, since the rods 127 have a semicylindrical shape, after hitting the
rods 127 parts of a cooling wind flow through the holes defined by the holes 1219
and the rods 127 and flow into the waveguide unit through holes defined by the holes
25 of the waveguide unit 2 and the rods 127, to produce a convectional air flow in
the waveguide unit. It is therefore expected that the occurrence of discharge between
the high-frequency wave output unit 111 and the waveguide unit 2 can be suppressed
further.
[0091] It is preferable that an even number of rods be arranged symmetrically so as not
to have directivity. However, the number, size, positions, shape, and directions of
the rods are not restricted at all as long as they enable positioning with respect
to the metal plate and the waveguide unit.
[0092] The rods 127 need not be press-fitted as long as they enable positioning with respect
to the metal plate and the waveguide unit.
[0093] Although it is preferable that the metal plate have such a simple structure as not
to have directivity, it may have any structure as long as it can be positioned with
respect to the yokes.
[0094] To suppress the magnetic loss, it is preferable that the rods be made of a non-magnetic
material. However, the rods may be made of any material as long as they enable positioning
with respect to the metal plate and the waveguide unit.
Industrial Applicability
[0095] The magnetron and the microwave-using apparatus according to the invention make it
possible to reliably positioning and fixing the high-frequency wave output unit of
the magnetron with respect to and to a magnetic yoke of the magnetron and the waveguide
unit of a microwave-using apparatus or the like, to suppress discharge between the
high-frequency wave output unit and the waveguide unit, to guide radio waves reliably,
without complicating their structures or assembling methods. As such, they can be
applied to or used as microwave-using apparatus such as microwave ovens.
Description of Reference Signs
[0096]
1: Magnetron
11: Vacuum Tube Part
111: High-Frequency Wave Output Unit
112: Anode Cylinder
12: Exterior Part
121: Magnetic Yokes
1211: First magnetic Yoke
1212: Second magnetic Yoke
1213: Cut and raised part
1214: Hole
1215: First magnetic yoke
1216: First Cut and Raised Part
1217: Second Cut and Raised Part
1218: First magnetic yoke
1219: Hole
122: Permanent magnet
123: Cooling Unit
124: Filter Unit
125: Metal Plate
126: Gasket
127: Rod
2: Waveguide Unit
21: Cut and Raised Part
22: Hole
23: First Hole
24: Second Hole
25: Hole
3: First Magnetic Yoke
31: Annular Rib
4: Positioning Plate
41: Baffle Plate