JPS6119371Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a probe holding device for a microwave oven that holds a temperature probe within a heating chamber, and aims to provide a structure that can hold the probe rotatably at a low cost. be.

This invention will be described below with reference to an embodiment shown in the drawings. In the figure, 1 is a microwave oven body, 2 is a heating chamber, 3 is a turntable driven by a motor 4,
5 is a magnetron that supplies radio waves into the heating chamber 2 via a waveguide 6; F is the food; 7 is a through hole formed in the center of the ceiling of the heating chamber 2; 8 is a temperature probe that measures the temperature of the food F. It consists of a temperature measurement section 9, a plug section 10, a flexible cord 11, and a grip section 12.

J is a jack to which the probe 8 is detachably attached, and is constructed as follows. i.e. 1
3 is a substrate attached to the ceiling of the heating chamber 2 so as to surround the through hole 7; 14 is a main body case; a circular metal lower case 16 having a through hole 15 in the center;
It is comprised of a circular metal upper case 18 that is fitted and fixed inside this and has an opening 17 in the center.

19 is a metal ring fitted in advance into the through hole 15, and 20 is an electrically insulating sleeve held inside this ring, made of plastic with a low coefficient of friction, and extending below the lower end surface of the ring 19. It stands out a little.

21 is a screw that passes through the main body case 14 vertically and fixes it to the board 13; 22 is an insulating case made entirely of heat-resistant plastic;
It has the following structure. That is, 23,
24 and 25 are three legs formed radially at equal intervals, two of which are hook-shaped and have a notch 26 in the center through which the screw 21 is inserted; Each leg 25 is also formed into a substantially oval shape having a through hole 27 through which the screw 21 is inserted.

28 are guide holes formed in the upper case 18 at equal intervals around the opening 17;
It has a shape that matches the external shape of the legs 23, 24, and 25. 29 is a small hole formed on a concentric circle centered on the opening 17; 30 is an insulating case 23;
An insulating substrate 32 is inserted from below into a groove 31 formed on the end surface of the insulating substrate and held therein, and 32 is a pair of fixed electrode plates whose center portions are supported by this substrate. The whole body has a U-shape that seems to fit between the two.

Reference numeral 33 denotes a hollow cylindrical rotary tube made of plastic having heat resistance and a low coefficient of friction, and is held rotatably in advance in the insulating case 22 by the clamping force of the fixed electrode plate 32.

Reference numerals 34 and 35 designate a pair of rotating electrode plates fitted to the circumferential surface of the rotating tube 33, and contact pieces 36 integrally formed on each electrode plate are connected to the inner circumferential surface of an insertion hole 37 formed in the center of the rotating tube 33. It protrudes elastically inward. Reference numeral 38 denotes a U-shaped spring facing the insertion hole 37 of the rotary cylinder 33, which engages with a small diameter portion 39 formed at the tip of the plug portion 10 of the probe 8 to prevent it from coming off.

In order to ensure that the rotating cylinder 33 rotates stably, the upper part of the insulating case 22 has a circular recess 40 for holding the rotating cylinder 33, and the rotating cylinder 33 itself has a stepped part 41 that fits on the outside of the ring 19. each formed.

In addition, inside the main case 14, the dimension A from the edge of the opening 17 of the upper case 18 is the fundamental wavelength of the high frequency used.
A circular chiyoke chamber 42 corresponding to 1/4 is formed. Reference numeral 43 indicates a plurality of ventilation holes formed on the upper surface of the insulating case 22, and 44 indicates a through hole similarly formed on the upper surface of the insulating case 22.

Next, the method of assembling the jack J will be explained. First, the substrate 13 is fixed in advance to the ceiling surface of the heating chamber 2 by welding or the like. On the other hand, a lower case 16 and an upper case 18, into which a ring 19 has been fitted in advance, are fixed together at their peripheral edges to form a main body case 14, and a fixed electrode plate 32, a rotating electrode plate 34,
An insulating case 22 in which a rotary cylinder 33 with a rotating cylinder 35 fixed therein is previously housed is detachably attached. That is, the insulating case 22 is positioned so that its legs 23, 24, and 25 align with the guide holes 28 of the upper case 18. In this case, the shapes of the legs 23, 24, and 25 ensure that the insulating case 22 is set in one position (orientation). Then, when the insulating case 22 is rotated counterclockwise when viewed from above with the legs 23, 24, and 25 recessed into the main body case 14, the notches 26 of the legs 23, 24, and 25 Through hole 2
7 is directly under the small hole 29 of the upper case 18, the rotation of the insulating case 22 is caused by the guide hole 2 of the upper case 18.
It is stopped at the 8-hole edge.

Therefore, next, this main body case 14 is attached to the previous board 13.
By placing it on top and tightening it to the board 13 with the screws 21, the main body case 14 is fixed, and at the same time, the insulating case 22 is also fixed in a predetermined position in a non-rotatable state, and the assembly is thus completed.

In the above configuration, the following operation will be explained. Since the probe 8 is now held by the jack J, when the plug part 10 is inserted into the insertion hole 37 of the rotary cylinder 33 through the ring 19, the plug part 10
The small diameter portion 39 is elastically held from both sides by springs 38, and the contact piece 3 is attached to the circumferential surface of the plug portion 10.
6 touch each other. As a result, the plug portion 10 is integrated with the rotary tube 33, so that the probe 8 can be held so that the rotary tube 33 rotates integrally with the rotation of the plug portion 10.

In this state, when the temperature measurement part 9 of the probe 8 is inserted into the food F and the magnetron 5 is driven, the operation of the magnetron 5 is automatically stopped when the temperature of the food F reaches a predetermined cooking temperature. It is.

During such cooking, radio waves in the heating chamber 2 are transmitted to the rotating cylinder 33.
Even if leakage occurs from the insertion hole 37 to the outside, the leakage radio waves can be extinguished because the chiyoke chamber 42 is formed to surround the rotary tube 33.

In addition, when the probe 8 is removed,
Radio waves are cut off when passing through the ring 19, so there is almost no leakage of radio waves, but when the probe 8 is attached, this probe part 10 plays a role of a kind of antenna, and the ring 19 Although there is a possibility that the radio waves propagate close to the upper edge of the radio wave and radiate to the surroundings, such radio waves are extinguished by the radio wave chamber 42 as described above.

Note that the opening 17 and the ventilation hole 43 of the upper case 18 serve as a communication part that communicates the chamber 42 with the outside, and the insulating case 22 connects the chamber 42 with the outside.
If steam or the like enters the interior of the heating chamber 2 from the heating chamber 2 side, it has the effect of discharging it by natural convection, thereby preventing dew condensation around the rotating cylinder 33 and reducing the risk of poor insulation at the electrical connections. is prevented from occurring.

In the above embodiment, when attaching the insulating case 22 to the main body case 14, the legs 23, 24, 2
5 and the guide hole 28, but it is clear that this is not absolutely necessary in this invention. Further, although the dimension of the yoke chamber 42 is set to be a radius of 1/4 wavelength from the opening 17 of the upper case 18, it may be formed to a radius of 1/4 wavelength from the insertion hole 37 of the rotating body 33.

As described above, in this invention, since the probe is held rotatably, even if twisting force is applied to the probe, this can be eliminated, and the life of the probe can be extended and the operability can be improved.

Furthermore, a metal main body case is provided corresponding to the through hole in the heating chamber wall through which the probe penetrates, and within this main body case there is a chiyoke chamber that expands in the direction perpendicular to the axial direction of the plug part of the probe, that is, in the radial direction. A rotary tube with an electrode plate that comes into contact with the probe is rotatably housed inside the tube, so the thickness of the main body case can be reduced, and at the same time, the length of the plug part of the probe can also be shortened. Strength is improved. Moreover, since the radio waves leaking from around the plug portion of the probe can be reliably extinguished by the chiyoke effect, it is possible to provide a stable power supply state and a highly safe probe holding device.

[Brief explanation of the drawing]

Fig. 1 is a simplified longitudinal sectional view of a microwave oven having a probe holding device of this invention, Fig. 2 is a longitudinal sectional view of the main part of the microwave oven in a state where the probe is removed, and Fig. 3 is a partially cutaway perspective view of the main part. , FIG. 4 is a perspective view of the main body case and the insulating case, and FIG. 5 is a plan view of the insulating case. In the figure, 2 is a heating chamber, 7 is a through hole, 8 is a probe,
10 is a plug portion, 14 is a main body case, 22 is an insulating case, 32 is a fixed electrode plate, 34 and 35 are rotating electrode plates, 43 is a ventilation hole (communication hole), and J is a jack.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A through hole is provided in the wall of the heating chamber through which the probe penetrates, and a metal main body case is attached to the outside of the heating chamber in correspondence with this through hole, and the main body case is A circular check chamber is formed inside so that the radius in the direction orthogonal to the axial direction of the plug section when the probe is inserted is a predetermined check dimension. A probe holding device for a microwave oven, which rotatably accommodates a rotary tube inserted into a microwave oven, and has an electrode plate attached to the rotary tube that comes into contact with a plug portion of the probe when the probe is inserted. (2) The probe holding device for a microwave oven according to claim 1, wherein a communication portion for ventilation is formed on the wall surface of the heating chamber.