JP2639068B2 - Cooker - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heating cooker such as a microwave oven having a bread kneading function.

2. Description of the Related Art In recent dietary habits, bread meals, mainly bread loaves, have become widespread at home in the style before rice was the staple food. As such bread foods have become widespread, it has already been known that a product which can satisfy the market needs for easily making bread at home has recently been invented and has been well received in the market. More recently, a microwave oven with a baking function has been invented, in which a microwave oven and a bread maker that makes bread are integrated, since microwave cooking can be easily performed and a bread maker that makes bread is widely used. The structure of the microwave oven with the bread making function will be described with reference to FIGS. 7 and 8.

FIG. 7 is a front sectional view showing the structure of a conventional microwave oven with a bread-making function when kneading and baking dough.
A dough material 3 is placed in a bread case 2 placed in the heating chamber 1. The dough material 3 is kneaded by the blades 4 installed at the bottom of the bread case 2. The blade 4 is inserted into a shaft 5 penetrating the bottom of the pan case 2. A connector 6 is provided at a lower end of the shaft 5. The connector 6 is fitted with a connector B8 fixed on the upper part of the support rotation shaft 7. The support rotary shaft 7 is supported by bearings 11 and B12 press-fitted into the inner circumference of a fixed shaft 10 fixed to the motor mounting plate 9, and rotates the inner circumferential surfaces of the bearings 11 and B12. A connector C13 fixed to the support rotation shaft 7 is provided below the support rotation shaft 7, and a distal end portion 14 of the connector C13 is connected to a projection 16 of the pulley 15. An oil-impregnated bearing 17 is press-fitted into the pulley 15 and the fixed shaft 10
To rotate the outer peripheral surface of. Reference numeral 18 denotes an oil pan for retaining oil contained in the oil-impregnated bearing 17. Pulley 15 is a motor
Since the rotation driving force of 19 is transmitted by the belt 20, the support rotation shaft 7 fixed to the connector C13 connected to the projection 16 of the pulley 15 rotates. The rotational driving force transmitted to the support rotary shaft 7 passes through the connector B8 and the connector 6,
The blade 4 in the bread case 2 is rotated to knead the dough material 3. The number of revolutions of the blade 4 is determined by the ratio of the motor 19 to the shaft diameter of the pulley 15 and the motor 19, and is set to about 300 revolutions per minute. The kneaded bread dough material 3 is fermented by the upper heater 21 and the lower heater 22 attached to the upper and lower surfaces of the heating chamber 1 and further baked.

FIG. 8 is a front cross-sectional view showing the structure of a conventional microwave oven with a bread making function when high-frequency heating is performed. In FIG. 8, a food placing table 23 is provided in the heating chamber 1 instead of the bread case 2.
Is inserted into the support rotation shaft 7. Dish on food table 2
24, and food 25 is placed on the top of the plate 24. A magnetron 26 is attached to the side surface of the heating chamber 1, and the food 25 is heated by radio waves emitted from the magnetron 26. Note that, in order to eliminate uneven heating of the food 25, the support rotating shaft 7 rotates similarly to the time of kneading the dough, so that the food placing table 23 inserted into the support rotating shaft 7 is rotated.
The rotation speed of the food placing table 23 is too fast at the time of dough kneading (about 300 rpm), and the food 25 flies by centrifugal force. 28, the number of rotations of the motor 19 is detected by the combination of the photo interrupter 29 and the control unit 30, and the number of rotations of the
It is designed to rotate at ~ 8rpm.

Problems to be Solved by the Invention However, the following problems exist in the microwave oven with the bread making function having such a configuration. The support rotation shaft 7 is
There is an advantage that no side pressure is applied because the inner circumference of the bearing press-fitted into the inner circumference of the fixed shaft is not applied.However, the oil-impregnated bearing press-fitted into the pulley is always subjected to side pressure by the belt because it rotates on the outer peripheral surface of the fixed shaft. ing. Generally, when using an oil-impregnated bearing, it is necessary that side pressure is not applied. This is because a uniform gap is provided between the fixed shaft 10 and the oil-impregnated bearing 17, and the gap is rotated by utilizing a film of oil oozing from the oil-impregnated bearing. Accordingly, when the lateral pressure is constantly applied, when the outer peripheral surface of the fixed shaft 10 and the inner peripheral surface of the oil-impregnated bearing 17 are in contact with each other, the pressure is always applied, and the rotation is performed at high speed without forming an oil film. And seizure of the bearing occurs. In addition, since a heater is provided near the oil-impregnated bearing, and the temperature of the bearing atmosphere becomes high, the oil used for the bearing must be high-temperature-resistant and the cost increases. Furthermore, in order to ensure sufficient durability, it is necessary to increase the amount of oil contained in the bearing, and for that purpose, the diameter of the bearing must be increased or the overall height of the bearing must be increased. It is disadvantageous in terms of space saving. In addition, since oil is used for the bearing, the oil slips on the belt and adversely affects the rotation performance. Therefore, an oil receiver is required, the structure is complicated, and handling of the bearing requires attention. As described above, the conventional microwave oven with a bread making function has a very difficult problem.

An object of the present invention is to solve such a conventional problem, and it is a first object of the present invention to provide an inexpensive, space-saving and highly reliable heating cooker such as a microwave oven with a baking function. Further, a second object is to provide a smooth rotation of the heated object mounting table particularly at a low speed rotation during high frequency heating.

Means for Solving the Problems In order to achieve the first object, the heating cooker of the present invention is controlled by a single electric motor and includes a supporting rotating shaft for rotating an object to be heated in the case of high-frequency heating, and a bread dough. Two bearings are provided to support the outer periphery of the shared support rotating shaft when kneading, and this bearing has a bearing surface with the support rotating shaft, which is impregnated with ethylene tetrafluoride and lead impregnated bronze. This is a configuration in which a ring-shaped steel plate having a layer is provided.

Further, in order to achieve the second object, the present invention provides a fixing device in which a part of a supporting rotary shaft is fixedly provided with an engaging means, and a second pulley is provided with a protrusion to which the engaging means is loosely fitted. A third bearing that rotates around the outer periphery of the supporting rotary shaft is press-fitted into the second pulley, and the third bearing has a bronze sintered layer impregnated with ethylene tetrafluoride and lead on a bearing surface with the supporting rotary shaft. A ring-shaped steel plate is provided.

The rotational driving force of the motor 1 is transmitted to the pulley by the belt. On the protrusion provided on a part of the pulley,
The engagement means fixed to the support rotation shaft is loosely engaged, and when the pulley rotates, the engagement means hits the protrusion of the pulley with some play and the support rotation shaft rotates.
Since the upper and lower pulleys and the pulleys themselves are fitted with bearings in which a ring-shaped steel plate having a bronze sintered layer impregnated with ethylene tetrafluoride and lead on the bearing surface is mounted on the bearing,
Even if lateral pressure is applied to the pulley by the belt, the load is absorbed by the elasticity of the layer of ethylene tetrafluoride and lead, and the frictional resistance, which is the advantage of ethylene tetrafluoride, is small, so that the supporting rotating shaft can rotate smoothly. It can be used under high temperature even with heat resistance. In addition, no oil is used for the bearing, so there is no need for an oil pan, and there is no risk of seizure due to running out of oil, and a simple configuration, space saving and high reliability can be obtained. It has an effect.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a front cross-sectional view showing the configuration of the cooking device of the present invention when kneading dough. Bread case 51 in heating room 50
Is installed. In the bread case 51, a blade 52 for kneading the powder
Is inserted into a shaft 53 penetrating the bottom of the bread case 51. A connector 54 is provided at the lower end of the shaft 53. The connector 54 is fitted with a connector B56 fixed on the upper part of the support rotation shaft 55. An engagement means 57 fixed to the support rotation shaft 55 is provided on a part of the support rotation shaft 55, and an end face 58 of the engagement means 57 is loosely engaged with the protrusion 60 of the pulley 59. Since the rotational driving force of the electric motor 61 is transmitted to the pulley 59 by the pulley B86 and the belt 62, the support rotating shaft 55 fixed to the engaging means 57 which is loosely engaged with the protrusion 60 of the pulley 59 rotates. I do. The rotation driving force transmitted to the support rotation shaft 55 passes through the connector B56 and the connector 54, and rotates the blades 52 in the pan case 51 to knead the dough. An upper heater 63 and a lower heater 64 are attached to the upper and lower surfaces of the heating chamber 50 to heat food in the heating chamber 50. Electric motor
An encoder 66 having a slit on the outer periphery is attached to the upper side of the rotating shaft 65 of the 61, and the number of rotations of the electric motor 61 is detected by a combination of a photo interrupter 67 and a control unit 68. A magnetron 69 is attached to the side surface of the heating chamber 50 to perform high-frequency heating.

FIG. 2 is a front sectional view showing the configuration of the heating cooker of the present invention during high-frequency heating. In FIG. 2, a food placing table is inserted into the heating chamber 50 in place of the bread case 51 on the support rotating shaft 71. A plate 72 is placed on the food placing table 70, and a food 73 is placed on the plate 72. In order to eliminate uneven heating by high-frequency heating, the support rotating shaft 71 rotates in the same manner as in the kneading of the dough, so that the food placing table 70 inserted into the supporting rotating shaft 71 is rotated.

FIG. 3 is an electric circuit diagram of a control unit of the heating cooker according to the present invention. Microcomputer 74 when kneading bread dough
By alternately outputting gate signals synchronized with the power signal of 50/60 Hz from the output boats O ₃ and O ₄ , the electric motor 61 repeats normal rotation and inversion. This will be described with reference to the timing chart of FIG. The power supply signal conversion circuit shown in FIG. 3 converts the AC 100 V signal into a DC waveform, and
Read by Io port. The microcomputer 74 outputs O ₃ at the time of forward rotation at the timing of the zero cross read at the Io port.
More, the electric motor 61 by issuing always H output from the O ₄ at the time of inversion can be the normal and inverted. At this time, since almost 100% of the power is supplied to the electric motor 61, the motor 61 rotates at full speed, is decelerated by the pulley 59, and the blade 52 rotates at approximately 300 rpm.

Next, motor control during high-frequency heating will be described with reference to FIGS. The AC100V signal is converted into a DC waveform by the power supply signal conversion circuit 75 in FIG. 3 and is read at the Io port of the microcomputer 74. The cycle of not energizing for a fixed period (two periods in FIG. 5) is repeated.

The power supplied to the electric motor 61 can be finely adjusted by varying the frequency at which the current is not supplied. On the other hand, the number of rotations of the electric motor 61 can be detected by counting pulses generated for a certain period of time by the microcomputer 74 when the slit provided in the encoder 66 blocks the photointerrupter 67. As described above, the number of rotations of the electric motor 61 is detected, and based on the result, the non-energized frequency is selected, so that feedback control is performed so that the food placing table 70 rotates at about 6 rpm.

As described above, a single motor performs high-speed rotation when the dough is kneaded and low-speed rotation when high-frequency heating.

FIG. 6 is an enlarged cross-sectional view of the support rotation shaft portion. In FIG. 6, the supporting rotary shaft 55 includes a bearing A78 and a bearing B formed of a ring-shaped steel plate having a bronze sintered layer impregnated with ethylene tetrafluoride and lead pressed into the bearing mounting plate A76 and the bearing mounting plate B77.
79 and rotates on the inner peripheral surfaces of the bearings A78 and B79. The bearing mounting plate A76 is fixed to a motor mounting plate 80 on which a motor (not shown) and the like are mounted.
Is fixed to a motor stopper 81. The motor stopper 81 regulates the protruding length of the support rotation shaft 55 in a heating chamber (not shown), and also serves as the stopper 8 so that the support rotation shaft 55 does not fall downward.

The pulley 59 is disposed between the bearing mounting plate A76 and the bearing mounting plate B77, and is a ring-shaped steel plate having a bronze sintered layer impregnated with ethylene tetrafluoride and lead in a sliding portion with the support rotating shaft 55. The formed bearing C82 is press-fitted and rotates on the outer peripheral surface of the support rotation shaft 55. The pulley 59 rotates by the rotational driving force of the electric motor (not shown) transmitted to the pulley 59 via the belt (not shown). When the pulley 59 rotates, the protrusion 60 provided on the pulley 59 comes into contact with the end face 58 of the engaging means 57 fixed to the support rotating shaft 55 via the Nami washer 83 with a tome 84 or the like, and pushes the engaging means 57. The support rotation shaft 55 rotates. At this time, since tension is applied to the pulley 59 by the belt, lateral pressure is applied to each bearing (78, 79, 82), but the load is absorbed by the elasticity of the layer of ethylene tetrafluoride and lead. In addition, since the frictional resistance, which is an advantage of ethylene tetrafluoride, is small, the support rotating shaft 55 can smoothly rotate.

A bush 85 made of a resin having good wear resistance is provided at a lower portion of the support rotation shaft 55 to prevent generation of chips due to metal contact between the support rotation shaft 55 and the motor stopper 81 during high-speed rotation. , So as not to adversely affect the bearing B79.

In addition, by providing play in the rotation direction between the pulley 59 and the engagement means 57, during low-speed rotation during high-frequency heating, a knocking phenomenon or rotation unevenness due to pulsation of the electric motor 61, etc.
Can be absorbed.

Effects of the Invention As described above, according to the cooking device of the present invention, the following effects can be obtained.

(1) The size of the through-hole on the bottom of the heating chamber is sufficient for one support rotating shaft, which makes it difficult for food debris, juice, oil, etc. to enter. A highly reliable heating cooker without fear can be provided.

(2) Since high-speed rotation during kneading of dough and low-speed rotation during high-frequency heating can be realized with a single electric motor, the electric motor and other components can be reduced, and an inexpensive heating cooker can be provided.

(3) Since oil is not used for the bearing, an oil pan is not required, and it can be used at high temperatures with heat resistance.
In addition, there is no fear of burn-in due to lack of oil in terms of life, space can be saved with a simple configuration, and high reliability can be obtained.

(4) Since all the rotating parts can adopt the slide bearing, a quiet and low-noise heating cooker can be realized.

According to the cooking device of claim (2), especially at low-speed rotation during high-frequency heating, the frictional resistance between the pulley and the supporting rotary shaft is small, so that the knocking due to the pulsation of the electric motor due to the play between the pulley and the engagement means. Phenomena and uneven rotation can be prevented, and smooth rotation can be obtained.

[Brief description of the drawings]

FIG. 1 is a front cross-sectional view showing a configuration of a heating cooker according to one embodiment of the present invention when kneading dough, FIG. 2 is a front cross-sectional view showing a configuration of a heating cooker of the present invention during high-frequency heating, and FIG. FIG. 3 is an electric circuit diagram of a control unit of the cooking device of the present invention, FIG.
FIG. 5 is a timing chart thereof, FIG. 6 is an enlarged sectional view of a supporting rotary shaft portion, FIG. 7 is a front sectional view showing a structure of a conventional microwave oven with a baking function when kneading from dough kneading, FIG. FIG. 2 is a front sectional view showing a structure of a conventional microwave oven with a baking function when performing high-frequency heating. 50 ... heating room, 51 ... bread case, 52 ... feather, 53 ...
Shaft, 54… Connector, 55… Supported rotating shaft, 56…
... Connector B, 57... Engaging means, 58... End face of the engaging means, 59... Pulley, 60.
Electric motor, 62 belt, 63 upper heater, 64 lower heater, 65 rotating shaft, 66 encoder, 67 photointerrupter, 68 control unit, 69 magnetenetron, 78
... Bearing A, 79 ... Bearing B, 82 ... Bearing C

Claims (2)

(57) [Claims] 1. A heating chamber, means for heating an object to be heated in the heating chamber, a support rotating shaft for rotating the object to be heated,
An electric motor for driving the support rotation shaft, a first pulley provided on the shaft of the electric motor, a second pulley coaxially with the support rotation shaft, the first pulley and the second pulley A first bearing that supports the outer periphery of the support rotation shaft above the second pulley, and a second bearing that supports the outer periphery of the tip of the support rotation shaft below the second pulley. A ring-shaped steel plate having a bronze sintered layer impregnated with ethylene tetrafluoride and lead is provided on the bearing surface of the first bearing and the second bearing on the bearing surface with the support rotating shaft. A heating cooker that is configured to do so. 2. A projecting portion in which an engaging means is fixed to a part of the supporting rotary shaft, and the engaging means is loosely engaged with the second pulley, and a third bearing which rotates on the outer periphery of the supporting rotary shaft. And the third bearing has a bearing surface with the supporting rotary shaft impregnated with ethylene tetrafluoride and lead with respect to the rotation of the second pulley. A heating cooker in which a ring-shaped steel plate having a bronze sintered layer is provided.