JPH0321218A - Dish washer - Google Patents

Abstract

PURPOSE:To prevent noise by controlling the discharge power of a pump in accordance with a degree of bumps detected by a piezoelectric element on the inner wall surface of a wash tank so as to restrain the sound of bumps of water jetted from a nozzle onto the inner wall surface of the washing tank, to a lower value. CONSTITUTION:A microcomputer 21 detects a number of pulses from a discharge power detecting circuit 25 in a predetermined time so as to detect a degree of bumps on the inner wall surface of a washing tank 2. Since the discharge power detecting circuit 25 delivers a pulse when an output voltage of a piezoelectric element is higher than a reference voltage, the larger the number of pulses in the predetermined time, the higher the degree of bumps of water jetted from a nozzle 11. The degree of bumps is determined in four stages in accordance with a number of pulses, and a microcomputer 21 set a triac energizing angle of a washing pump 12' in accordance with a detected and determined degree of bumps, that is, the larger the bumps, the smaller than the triac energizing angle is set. When the triac energizing angle is changed, the discharge capacity of the washing pump 12 varies, that is, the larger the degree of bumps, the lower the discharge capacity becomes so as to restrain the degree of bumps to a small value. However, it sometimes causes the efficiency of washing to be lowered. Accordingly, the washing time is prolonged from a regulated time T0, and the number of rinsing is increased from a regulated number No.

Description

[Detailed description of the invention] [Industrial application field] FIELD OF THE INVENTION The present invention relates to a dishwasher.

[Conventional technology]

In general, dishwashers are manufactured by, for example,
As seen in Publication B (A47L 15/42), water is sucked in by a water pump in a water storage part recessed at the bottom of the washing tank and sprayed from a nozzle to clean the dishes in the dish basket stored in the washing tank. The structure is such that cleaning is performed using sprayed cleaning water.

[Problem to be solved by the invention]

However, in this kind of dishwasher, the nozzle placed at the bottom of the washing barrel rotates and sprays washing water, so it is fine when there are many dishes in the dishwasher basket, but when there are few dishes in the dishwasher. This has the drawback that the cleaning water blown up from the nozzle hits the top wall of the cleaning tank with great force, producing a loud impact sound.

In order to completely solve this problem, for example, Japanese Patent Application Laid-Open No. 50-9255
In Publication No. 8, when a soft polyurethane resin or the like is injected and foamed between the outer frame of the dishwasher and the washing tank, a vibration damping plate is installed inside the resin to increase the attenuation of vibrations caused by the collision of washing water. We are trying to reduce noise.

However, providing a vibration damping plate between the outer frame and the washing tower as described in this publication not only complicates the structure of the dishwasher, but also causes inconveniences such as significantly increasing man-hours during manufacturing. .

This proposal was made with these problems in the conventional technology in mind, and the purpose is to reduce the impact noise caused by cleaning water without requiring major structural changes. It is intended to provide a dishwasher.

[Means to solve the problem]

In order to achieve the above object, the dishwasher of the present invention includes a piezoelectric element that is attached to the inner wall of the washing tank and detects the degree of impact caused by washing water sprayed from a nozzle by a pump; The present invention is characterized by comprising a control means for controlling the discharge capacity t of the pump to be weak or strong depending on the magnitude of the impact level.

[Effect]

According to the above configuration, the degree of impact on the inner wall surface of the cleaning tank due to the water jetted from the nozzle is directly detected by the piezoelectric element attached to this, and the discharge capacity of the pump is controlled according to this degree of impact. Therefore, the jetting force from the nozzle is adjusted to suppress the degree of impact on the inner wall surface, thereby preventing noise.

〔Example〕

An embodiment will be described with reference to the drawings.

First, Figure 1 shows the overall configuration of a dishwasher, where fl+ is the main body of the washing machine, (2) is a washing tank formed inside the main body ill, and a dish basket (3) containing dishes can be freely pulled out. The front opening of the cleaning tank (2) is closed by the door (4). (5) is a water reservoir provided in a recessed manner at the bottom of the cleaning knob (2), and {6} is a leftover filter attached to the water reservoir (5).

(7) is a water supply hose that is connected to a water faucet using a magic joint (8), and by opening the water supply valve (9) installed at the end of this hose, the cleaning tank can be accessed from the water inlet (IO). (Water will be supplied within 2 →.

(11) is an arm nozzle rotatably provided at the bottom of the cleaning tank (2), (l2l is a cleaning device that sucks water in the water storage part {5} and sprays it from the nozzle (11) into the cleaning tank (2+). The nozzle (Ill) is a pump (12l).
The water discharged from the nozzle (1 liter) provides a rotational driving force corresponding to this pressure, and the nozzle (1 liter) injects cleaning water while rotating.

(13l is a drainage pump, which discharges the water in the water storage part (5) through the drainage hose Ll41, (151 gold). (
I6l is a sheathed heater installed at the bottom of the cleaning tank {2}, (171 is the cleaning tank (2) via the intake and exhaust port (18)
The blower (19) that blows outside air inside is a float switch that detects the water supply level.

The steel is a piezoelectric element attached to the inner surface of the earthen wall of the cleaning spray (21), and the discharge force (impact degree) of the cleaning water from the nozzle (11)
Outputs a voltage proportional to .

In addition, a control device for fully automatic control of the cleaning process, drying process, etc. is provided on the lower front side of the main body (11+).
An operation panel section is provided on the lower front side of the unit.

Figure 2 shows the circuit block diagram of a dishwasher. (2l) is a microcomputer (hereinafter referred to as microcomputer) as a control/inhibition means that controls the entire system, and (2l) is a microcomputer installed in the drying panel. LED for displaying each process of washing, rinsing, and drying
241 is the key switch input circuit that detects the contact operation of the operation keys and float switch (19) on the operation panel; There is a temperature detection circuit that converts the signal from the thermistor that detects the control temperature during drying into a signal that can be input to the microcomputer 121+.

4 compares the output voltage from the piezoelectric element 4 with a reference voltage, and if it is higher than the reference voltage, sends a pulse signal to the microcomputer Zl1.
4 is a microcomputer t211t-
This is a reset circuit for initialization.

(B) is a load drive unit that controls the drive of various AC loads according to control signals from the microcomputer rule, and this AC load includes a blower (1) blower motor (17f' * drainage pump (I3)) Bump motor (131'), water supply valve (9), cleaning bomb motor (1〆) of cleaning pump (12), sheath heater (161 m), bimetal for detergent injection, etc.

Here, the cleaning pump motor (12), which is the same as the load drive unit, is controlled by adjusting the additional power angle of the triac provided in the current-carrying path of the motor (121).

Section 431 is an external interrupt circuit that notifies the microcomputer of the zero-crossing point of the commercial power source.

The control procedure for each course is preprogrammed in the microcomputer (2l), and in addition to this, a program for adjusting the discharge capacity of the washing pump (12l) shown in Fig. 3 is provided, and this program controls the washing operation. Executed immediately after the start of.

In a dishwasher configured as described above, when the start key is operated after selecting a course on the operation panel,
Input circuit (4) Signals according to key operations are sent to the microcontroller (2)
1), and the microcomputer 12l} starts the control operation.

For example, in the case of a standard course consisting of each process of washing, rinsing, and drying, first, the water supply valve (9) is opened by the microcomputer (21), water is supplied into the washing tank (2), and the water level is reached at a predetermined level. When the water reaches the water supply valve (9), the float switch (19) is activated and the microcomputer (2L) operates the water supply valve (9).
) is closed.

Thereafter, the cleaning pump motor (121) is driven, detergent is injected, and the cleaning water in the water storage section (5) is blown up from the nozzle (11j) into the cleaning tank (2) by the cleaning pump (12), thereby cleaning. An action is taken.

The washing water sprayed from the nozzle (l1) is used to clean dishes and washing dishes (
2} and returns to the bottom, and is stored in the water storage part (5) again, where the cleaning water is circulated by driving the pump (12).

And a microcomputer! 2l) executes the program shown in FIG. 3 immediately after this cleaning operation.

That is, the microcomputer 1211 counts the total number of pulses from the ejection force detection circuit (26) in a predetermined time in steps St and S2, and detects the degree of impact on the inner wall box of the cleaning tank (2) from this number of pulses in step S3.

As mentioned above, the ejection force detection circuit 4 is a piezoelectric element (20).
Since a pulse is output when the output voltage of the nozzle (I1
) The impact level of the jet water is large.

With S3 Step, the degree of impact can be determined in four stages depending on the number of pulses, and then the microcomputer!
21+ sets the triax energization angle of the cleaning pump motor (121') in accordance with the detected and determined impact degree, that is, the greater the impact degree, the smaller the triax energization angle is set in step S4.

Here, if the triax energization angle is changed based on the above settings, the discharge capacity of the cleaning pump (l2) will also change accordingly, and the greater the impact degree, the lower the discharge capacity. Although this makes it possible to suppress the degree of impact on the inner wall surface of the cleaning tank (2), the cleaning rate may decrease accordingly.

For this reason, in step S5, when the discharge capacity setting becomes smaller, the cleaning time is extended from the specified time TO in accordance with the degree, and similarly, in step S6, the number of rinses is increased from the specified number of times NO. .

After the microcomputer (21) finishes the program shown in Figure 3, it again enters the control of the cleaning process, changes the tri-ax energization angle of the cleaning pump motor (1d) to the set energization angle, and performs subsequent cleaning using this energization angle. and drives the motor 02+ during the stitching.

When the cleaning for the cleaning time set in step S5 is completed, the microcomputer (■■■l) stops the cleaning pump (Fig. is discharged, thereby completing the cleaning process.

Next, the process moves to the f-stopping process, where water is supplied again to a predetermined water level under the control of the microcomputer GL+, and the cleaning pump TL2
1, washing water is sprayed to perform a rinsing operation, and water is drained after a preset rinsing time has elapsed, completing one rinsing operation.

During this rinsing operation, the cleaning pump motor (+21') is driven at the triax energization angle whose setting was changed as described above, so that the cleaning water injected from the nozzle (!l) flows into the cleaning tank (2). A large impact force will not be applied to the inner wall surface.

The water supply, injection, and drainage rinsing operations are repeated the number of times set in step S6, and the final -t
At the time of heating, the sheathed heater (16) is energized, and so-called high-temperature heating is performed.

When the rinsing process is completed in this way, the next step is the drying process, where the sheathed heater (l6)
is driven, the air in the cleaning tank (2) is warmed, and the moisture adhering to the dishes is evaporated, and the blower (17l) is driven, and the steam trapped inside the cleaning tank (2+) is discharged to the outside. , these actions dry out the food benefits.

In the above embodiment, in order to control the discharge capacity of the cleaning pump (12), the input to the motor t121' was controlled by phase control of the triax, but the present invention is not limited to this. Alternatively, the discharge capacity may be controlled by input control of the motor (1 field) using inverter control.

[Effects of the Invention] Since the present invention is configured as described above, it produces the following effects.

The discharge capacity of the pump is controlled according to the degree of impact detected by the piezoelectric element on the inner wall of the cleaning tank.
Impact noise on the inner wall surface of the cleaning tank caused by water jetted from the nozzle can be suppressed to a low level, and noise can be prevented.

Moreover, there is no need to provide a vibration damping plate as in the conventional publication, and soundproofing can be achieved by attaching a piezoelectric element to the inner wall surface of the cleaning tank, so there is no problem such as a significant increase in man-hours during manufacturing.

[Brief explanation of drawings]

The drawing shows one embodiment of the dishwashing shaft according to the invention, the first
The figure is a schematic cutaway side view, FIG. 2 is a circuit block diagram, and FIG. 3 is a flowchart for explaining the operation. (2)...Cleaning tank, (II)...Arm nozzle, (I
2! P, CO...piezoelectric element, f211 microcontroller.

Claims (1)

[Claims] (1) In a dishwasher that cleans the dishes stored in the washing tank by sucking water from the bottom of the washing tank with a pump and spraying it into the washing tank from a nozzle, it is attached to the inner wall surface of the washing tank. a piezoelectric element that detects the degree of impact caused by the water jetted from the nozzle; and a control means that controls the discharge capacity of the pump to be weak or strong depending on the magnitude of the degree of impact detected by the piezoelectric element. Features a dishwasher.