JPH0321713Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention relates to a kneader for kneading bread ingredients consisting of wheat flour, water, and the like.

(Prior Art) In recent years, home-use bread makers have been provided that automatically perform various steps such as kneading bread ingredients, fermentation, and baking. In the case of a kneader used in such a bread maker, conventionally, a kneading blade is rotatably disposed at the inner bottom of a container for introducing bread ingredients with an open top, and the kneading blade is rotated by a motor. It has a structure that allows it to be driven. Further, in such a kneader, the kneading blades and hence the motor are always driven to rotate in only one direction.

(Problems to be solved by the invention) Bread ingredients have a relatively high viscosity and a relatively large weight, and the torque required to rotate the kneading blades is relatively large. As a result, the kneading blades and thus the motor may become locked during the kneading operation. Furthermore, in actual kneaders, the kneading blades are driven intermittently during the kneading operation, and in this case as well, the motor may become locked each time it is started. However, in a conventional configuration in which the motor is driven to rotate in only one direction, when the kneading blades are stopped after the kneading operation has started, the torque required to start the kneading blades in that state is insufficient. , which is even larger than the torque required at the beginning of the kneading operation. For this reason, in the conventional structure, when the lock state as described above occurs, the lock state may continue for an unnecessarily long time. Problems are raised.

The present invention was developed in view of the above circumstances, and its purpose is to quickly release the locked state even if the motor becomes locked during kneading operation, thereby improving the kneading of bread ingredients. To provide a kneader that has effects such as eliminating the risk of running out of water or overheating the motor.

[Structure of the invention] (Means for solving the problems) The present invention provides a kneading machine that performs the kneading operation of bread ingredients using the rotational force of a motor, which includes current detection means for detecting the load current of the motor. Further, storage means is provided for storing a maximum load current value at the time of starting the motor based on the detection output thereof, and further, a storage means is provided for storing a maximum load current value at the time of starting the motor based on the detection output thereof, and a storage means is further provided for storing a maximum load current value at which the current detected by the current detection means is stored in the storage means during the kneading operation. The present invention is configured to include rotation control means for rotating the motor in reverse when the current value is reached.

(Function) At the start of the kneading operation of bread ingredients, that is, when the motor is started, the maximum load current value of the motor is stored in the storage means. The value is close to the lock current. Therefore, when the motor is locked during kneading operation and a lock current flows through it, the current detected by the current detection means reaches the maximum load current value stored in the storage means. In response, the rotation control means causes the motor to rotate in the opposite direction. In this case, once the kneading operation has started, a large load is acting on the kneading blade in the direction of rotation, but not so large a load is acting on the kneading blade in the opposite direction. Yes, when the motor rotates in reverse as shown above,
This allows the motor to be started smoothly, and the locked state of the motor is quickly resolved.

(Example) Hereinafter, an example in which the present invention is applied to a bread maker will be described with reference to the drawings.

In FIG. 3 showing the overall configuration of the bread maker,
1 is an outer case, 2 is an inner case, 3 is a lid, and 4 is a container detachably housed in the inner case 2 via a bayonet mechanism 5. In this container 4, bread ingredients D are kneaded, fermented, and It is designed to go through a series of baking steps. Reference numeral 6 denotes a kneading motor, whose rotating shaft 6a protrudes into the container 4 by penetrating its bottom, and a kneading blade 7 is removably attached to the rotating shaft 6a. Particularly in this case, the motor 6 used is one that can rotate in forward and reverse directions. Further, 8 is a heater for baking bread arranged at the inner bottom of the inner case 2, 9 is a thermistor provided to detect the temperature of the container 4, and 10 is a control circuit mounted on the side wall of the outer case 1. It is a device.

The control circuit device 10 is for controlling a series of steps of kneading, fermenting, and baking the bread ingredients D in the container 4, and FIG. 1 shows a schematic configuration of the control circuit device 10. It is shown. That is, in FIG. 1, the heater 8 is connected to both ends of an AC power source 11 via a heater triac 12. Further, in the case of the motor 6, its forward rotation terminal A and reverse rotation terminal B are connected to one end of an AC power source 11 via a forward rotation triax 13 and a reverse rotation triax 14, respectively, and the common terminal C is It is connected to the other end of the power supply 11.

15 is a current detection means for detecting the load current flowing to the motor 6, and this is constituted by each circuit element described below. That is, 16 is a current transformer interposed in the current-carrying path of the motor 6, and 17 is the current transformer 1.
A diode 18 rectifies the secondary current of the diode 17, a capacitor 18 smoothes the output of the diode 17, and a sampling resistor 19 connected in parallel with the capacitor 18. A voltage proportional to the load current appears. Reference numeral 20 denotes an A-D converter, which converts the voltage across the resistor 19 into a digital voltage signal, and outputs the converted voltage as a data signal Sa indicating the load current of the motor 6.

Now, 21 is a control circuit which has both the functions of storage means and rotation control means in the present invention. This control circuit 21 includes a microcomputer, and includes a data signal Sa from the A/D converter 20, a temperature information signal given from the thermistor 9 via the A/D converter 9a, and a temperature information signal as shown in the figure. Each trial 1 is
2 to 14 are turned on and off, thereby executing the series of steps described above. However, among the control contents by the control circuit 21, the control contents during the kneading operation, which are related to the gist of the present invention, will be explained here, with reference to FIG. 2 as well as related effects. That is, the control circuit 21
When a command to start the kneading operation of bread material D is given at time _t1 in FIG.
A trigger signal S13 (see FIG. 2b) is applied to the gate of No. 3, thereby turning on the triac 13. Then, the motor 6 is energized through the forward rotation terminal A, and in response to this, the kneading blades 7 are rotated forward and the kneading operation of the bread material D is started. As the motor 6 is energized, its load current changes as shown in FIG. 2a, and a data signal Sa indicating the load current is applied to the control circuit 21 in real time. At this time, in the control circuit 21,
Based on the data signal Sa given as above, the maximum value Imax of the load current is stored in the internal storage area, and this stored maximum value Imax is
This value is close to the lock current of the motor 6. Thereafter, in the control circuit 21, when the load current indicated by the data signal Sa exceeds the maximum value Imax stored as described above, in other words, the control circuit 21 controls the motor 6.
falls into a locked state (time in Figure 2).
t ₂ ), the output of the trigger signal S13 is stopped, and a trigger signal S14 (see FIG. 2c) is applied to the gate of the reverse triax 14.
As a result, the motor 6 is energized through the reverse rotation terminal B, and the kneading blades 7 are rotated in the opposite direction. Furthermore, the control circuit 21
is configured to reverse the output states of the trigger signals S13 and S14 each time the load current exceeds the maximum value Imax, and therefore, each time the motor 6 becomes locked, its rotation direction is reversed.

In short, according to the above structure, when the motor 6 becomes locked during the kneading operation of the bread ingredients D, the motor 6 is rotated in the opposite direction. In this case, once the kneading operation has started, a large load is acting on the kneading blade 7 in the rotational direction up to that point, but not so large a load is acting on the kneading blade 7 in the opposite direction. When the motor 6 rotates in reverse as described above, this is smoothly started. Therefore, even if the motor 6 falls into a locked state, the locked state can be quickly released.

In the above embodiment, the functions of the storage means and the rotation control means are obtained by a program by a microcomputer, but each of these functions may be obtained by a hardware circuit using discrete components.

[Effects of the invention] According to the present invention, as is clear from the above explanation, even if the motor becomes locked during the operation of kneading bread ingredients, the locked state can be quickly resolved. This has the practical effect of eliminating the risk of insufficient kneading of bread ingredients or overheating of the motor.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a wiring diagram of the electrical configuration, FIG. 2 is a timing chart for explaining control details, and FIG. 3 is a longitudinal sectional view of the entire device. In the figure, 4 is a container, 6 is a motor, 8 is a heater, 1
0 is a control circuit device, 15 is a current detection means, 16 is a current transformer, 9a and 20 are AD converters, and 21 is a control circuit (storage means, rotation control means).

Claims (1)

[Scope of utility model registration request] In a device that performs a kneading operation of bread ingredients using the rotational force of a motor, the present invention includes a current detection means for detecting a load current of the motor, and a maximum load current value at the time of starting the motor based on a detection output of the current detection means. and a rotation control means for rotating the motor in the reverse direction when the current detected by the current detection means reaches the maximum load current value stored in the storage means during the kneading operation. kneader.