JP2000237114A - Tableware washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save water and energy, and to provide prescribed washing and drying performance by providing backward/forward blade-shaped parts having an exit angle set to almost 90 degree or more ion inside/outside parts in normal rotation for a first centrifugal impeller and a circular arc shape and an almost radial directional straight line shape contacting with an outer peripheral part for a second vortex impeller. SOLUTION: A first centrifugal impeller 11 has respectively backward/forward blade-shaped parts having an exit angle set to almost 90 degrees or more in inside/outside parts, and a second vortex impeller 14 has a blade-shaped part composed of a circular arc shape almost contacting with an outer peripheral part in normal rotation and an almost radial directional straight line shape in reverse rotation. Thus, when bubbles and air are mixed with wash water and are sent into a pump, the backward blade-shaped part inside of the centrifugal impeller 11 of normal rotation is pressurized by being filled with the wash water having a small air mixing ratio to be sent into a washing nozzle. The rotational direction of an electric motor 21 is reversed in washing and draining, with large a load of the centrifugal impeller 11 and small load of the vortex impeller 13 at washing time. In draining time, vice versa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dishwasher having a pump for pressurizing washing water, and more particularly to an impeller of a pump and a method of operating the same.

[0002]

2. Description of the Related Art A conventional dishwasher will be described with reference to FIGS.

When washing dishes, dishes to be washed are stored in a dish basket 52 of a washing tank 51, and a detergent is added to start the operation. When the operation is started, first, a water supply step of supplying a predetermined amount of cleaning water to the cleaning tank 51 necessary for stabilizing the operation of the cleaning pump 53 pressurizing the cleaning water is executed. The cleaning pump 53 has a general centrifugal impeller 54 having a backward-facing blade-shaped portion, and an electric motor 55 for driving the same.

[0004] Then, a main washing step is performed in which the washing water pressurized by the washing pump 53 and heated by the heater 56 is ejected from the ejection port of the washing nozzle 57 together with the detergent. The cleaning water is injected vertically or obliquely upward from the injection port of the cleaning nozzle 57. Further, the cleaning nozzle 57 is rotated substantially horizontally by the injection reaction force. The collision force of the washing water injected from the rotating washing nozzle 57
The dishes are washed by the action of detergent, heat and the like.

After the washing water rises to a predetermined temperature and passes through a main washing step for a predetermined time, the washing water containing dirt washed off from the dishes and the like is then discharged to the outside by a drain pump 58 to a draining step. enter. Subsequently, a water supply step of newly supplying cleaning water, a rinsing step of spraying cleaning water from the cleaning nozzle 57 to rinse tableware soiled with detergent or garbage (the dirt attached to the tableware is also called garbage), The above drain process is repeated four times in succession, and the washing process is completed.

In particular, in order to perform the subsequent drying step in a short time, the final rinsing step is a heating rinsing step performed while heating the cleaning water by the heater 56. A control device 59 controls the cleaning pump 53, the heater 56, the drain pump 58, and the like.

[0007]

The dishwasher having the above-mentioned conventional construction has the following problems with respect to the operation of the washing pump in the washing step.

In the cleaning process, if fine bubbles or air are sucked into the cleaning pump 53, the cleaning water cannot be pressurized.
In a conventional general centrifugal pump, when the amount of air increases, pumping becomes impossible. The amount of air that can be pumped is 10
~ 15% or less. In addition, the operating state of the pump in a state including such air is unstable, and generates a large operating noise.

Particularly, in a dishwasher, the washing pump 53
Such an operation state makes it impossible to normally perform the injection force from the cleaning nozzle 57 and its rotation. That is, there is a possibility that the originally required cleaning power as a dishwasher may not be obtained.

In order to prevent this, the supply amount of cleaning water is set to a predetermined amount that is large enough to obtain a required water amount and water depth so that air does not enter the cleaning pump 53 in the cleaning process. You. On the other hand, the heating capacity of the heater 56 is limited by the power supply capacity of the device. Therefore, in order to heat the predetermined amount of washing water and tableware to a predetermined temperature in the cleaning process, a long-time operation and power consumption are required.

Further, when the cleaning pump 53 is operated, the water level is lowered due to the circulation of the cleaning water, and the opening area is reduced by collecting residual foods on the filter 60 as the cleaning process proceeds. I do. For this reason, it becomes difficult for cleaning water to be supplied to the cleaning pump 53, and air enters easily. When air enters, the cleaning pump 53
May greatly fluctuate, resulting in loud noise. Further, the cleaning nozzle 57 stops rotating because the pressurized cleaning water cannot be sufficiently supplied to the cleaning nozzle 57. Therefore, there is a fear that the cleaning power cannot be exhibited. In order to avoid these, a sufficient amount of cleaning water is set as a predetermined amount.

Further, two electric motors are used to drive the cleaning pump 53 and the drainage pump 58, which is problematic in terms of downsizing of the mechanism and assembly. In order to solve this problem, the inventors have filed Japanese Patent Application No. 7-2894.
82, proposed a dishwasher such as Japanese Patent Application No. 7-292404. However, even in these pumps, the pump blade shape is a general centrifugal impeller having a backward-facing blade-shaped portion, so that the pump shows the same behavior as that of the conventional one regarding air entry. In addition, the vortex impeller in such a pump has a blade shape composed of an arc shape substantially in contact with the outer peripheral portion and a substantially linear shape in the radial direction, as also proposed by the present inventors in Japanese Patent Application No. 2-269125. By having the portion, it is possible to obtain the pressurizing capacity of the pump in a predetermined rotation direction, so-called forward rotation, and hardly obtain the pressurizing capacity in the reverse rotation.

The present invention solves the problems of the conventional dishwasher as described above. In particular, with a pump impeller configuration and its operation method, a dishwasher that can achieve a predetermined cleaning performance in a short time can be achieved by not only reducing the size of the cleaning mechanism, but also reducing the amount of washing water and power consumption. It is intended to provide.

[0014]

DISCLOSURE OF THE INVENTION The dishwasher of the present invention comprises:
A tableware for storing an object to be washed, a washing tank containing these, and a washing nozzle having an ejection port for ejecting washing water,
It has a pump for pressurizing the washing water by the rotation of the electric motor, and means for reversing the electric motor. The pump includes a first casing that discharges cleaning water to a cleaning nozzle by a first centrifugal impeller, a second casing that discharges cleaning water to the outside by a second vortex type impeller, and a first casing. The first centrifugal impeller is provided with an outlet angle of about 90 degrees or less on the inner side of the first centrifugal impeller with respect to the forward rotation, provided with a washing water guide portion communicating with the casing, the second casing, and the washing tank. The second swirl type impeller has a vane-shaped portion and a forward vane-shaped portion having an outlet angle set to about 90 degrees or more on the outer side, and the second swirl type impeller has an arc shape substantially in contact with an outer peripheral portion and a substantially radial linear shape. And a blade-shaped portion comprising:

According to the present invention, the pump that rotates forward in the washing step flows out from the forward-facing blade-shaped portion on the outer side of the first centrifugal impeller when the washing water is sent in a state containing air. Because of the high absolute velocity of the fluid, the air is sent to the outer periphery of the first centrifugal impeller in a short time. For this reason, the inside rearward vane-shaped portion is quickly filled with the cleaning water having a low mixing ratio of air, and the cleaning water can be pressurized. Then, the air and the washing water can be sent to the washing nozzle, and the washing water is jetted from the washing nozzle and the rotation is normally performed.

Since the washing water containing the air can be pressurized and circulated by the first centrifugal impeller as described above,
The level and amount of washing water to be supplied can be reduced as compared with a general centrifugal pump.

When the pump is operated, the washing water circulates to lower the water level. Further, as the washing process proceeds, the residual area is collected in the filter, and the opening area decreases. As described above, even when the washing water becomes difficult to be supplied to the pump and air easily enters the pump, the air is quickly discharged by the operation of the first centrifugal impeller, and the air enters the pump. Unbearable.

As a result, the pressurizing capacity of the pump in the cleaning step is stabilized without a large fluctuation. As a result, the fluctuation of the operation noise of the equipment falls within a substantially constant range. That is, the pressure fluctuation capacity of the cleaning pump and the fluctuation width of the injection pressure of the cleaning nozzle are small, so that excellent cleaning performance and quiet operation noise can be obtained.

Further, by reducing the amount of washing water to be supplied, the total heat capacity of washing water and tableware is reduced, and in the washing step, it can be heated to a predetermined temperature with the same heating capacity in a short time. . That is, it is possible to provide a dishwasher capable of achieving predetermined washing performance and drying performance while saving water and saving energy.

Further, in this pump, the direction of rotation of the motor is reversed by the forward / reverse reversing means during washing and drainage. At the time of cleaning in the forward rotation, the load of the first centrifugal impeller having the forward blade shape is large, and the load of the second vortex impeller having the arc-shaped blade shape substantially in contact with the outer peripheral portion is small. On the other hand, when the water is drained in the reverse rotation, the load of the first centrifugal impeller having the backward facing blade shape is smaller than that at the time of cleaning, and the load of the second vortex type impeller having the substantially linear shape in the radial direction is smaller than that at the time of cleaning. growing.

That is, the electric motor that drives both impellers can set the amount of current to be supplied in a constant range without greatly changing the load, which is the sum of both impellers, in the respective rotating directions of washing and drainage. Therefore,
The miniaturization of components constituting the control device for controlling these operations is realized.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is characterized in that a tableware for storing an object to be cleaned, a cleaning tank in which these are housed, a cleaning nozzle having an injection port for injecting cleaning water, and rotation of an electric motor. A pump for pressurizing the washing water, a forward / reverse inversion means of the electric motor, the pump comprising a first casing for discharging the washing water to a washing nozzle by a first centrifugal impeller; and a second vortex type impeller. And a washing water guide communicating with the first casing, the second casing and the washing tank, and the first centrifugal impeller has an inner part. Having a forward-facing vane-shaped portion having an exit angle set to approximately 90 degrees or less with respect to a predetermined rotation direction, and having a forward-facing vane-shaped portion having an exit angle set to approximately 90 degrees or more on the outer portion. 2 swirl type impeller rotates forward Is that in which a dishwasher having a blade-shaped portion consisting of a linear shape in a substantially radial direction with respect to the arcuate shape and reverse rotation in contact substantially in the outer peripheral portion by.

According to this invention, when the washing water is mixed with air and sent to the pump, the absolute velocity of the fluid flowing out of the forward-facing wing-shaped portion is large, so that the air is first. To the outer periphery of the centrifugal impeller.
For this reason, the inside rearward vane-shaped portion is filled with the washing water having a small mixing ratio of air, and the washing water can be pressurized. Then, air and cleaning water can be sent to the cleaning nozzle, and the cleaning power is exerted by jetting from the cleaning nozzle and rotating it.

Since the washing water containing air can be pressurized and circulated by the first centrifugal impeller as described above,
The amount of cleaning water to be supplied can be reduced as compared with a general centrifugal pump. Therefore, the heat capacities of the washing water and the tableware are reduced, and this can be heated to a predetermined temperature in a short time with the same heating capacity. That is, it is possible to provide a dishwasher capable of achieving predetermined washing performance and drying performance while saving water and saving energy.

In this pump, the direction of rotation of the motor is reversed between washing and draining. However, during washing, the load on the first centrifugal impeller is large and the load on the second vortex impeller is small. During drainage, the load on the first centrifugal impeller is small and the load on the second vortex impeller is large. That is, the load of the electric motor can be set within a certain range without greatly changing the load under each operating condition. Therefore, miniaturization of components constituting the control device for controlling these operations is realized.

According to a second aspect of the present invention, there is provided the dishwasher according to the first aspect, wherein the first centrifugal impeller is arranged such that the number of blades of the forward-facing blade-shaped portion is larger than that of the rearward-facing blade-shaped portion. That is.

According to the present invention, as in the first aspect of the present invention, the pump can be stably operated with a small amount of washing water, so that the heat capacity of the washing water and the dishes can be reduced. That is, it can be heated to a predetermined temperature in a short time, and a predetermined cleaning performance and drying performance can be obtained. In addition, by inverting and operating the electric motor in the draining process, the drainage is performed while the cleaning water is sprayed onto the object to be cleaned. For this reason, the dirt adhered to the tableware can be rinsed and the dirt contained in the washing water can be discharged while stirring, so that the amount of dirt remaining in the machine after each rinsing step is reduced, and high rinsing performance is achieved. can get. In the cleaning process, the outward-facing vane-shaped portion acts as a forward-facing blade at the time of such reversal, so that the pressurizing ability of the cleaning water is exhibited with a smaller load, that is, an amount of electricity.

In particular, in the forward blade-shaped portion having a large number of blades and a small interval therebetween, the air entering the pump can be discharged in a shorter time. Moreover, since the number of blades is large at the outer portion having a large diameter, the gap of the blade-shaped portion can have a certain size or more from the central entrance to the outer portion. That is, even if solid matter enters the pump,
There is no clogging due to foreign matter accumulating at the inlet of the pump.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, a part of the forward wing-shaped portion is connected to the rearward wing-shaped portion and the height thereof is substantially the same. The forward vane-shaped portion not connected to the portion is a dishwasher whose height is formed at a low level.

In the present invention, in particular, the blade height of a part of the forward wing-shaped portion not connected to the rearward wing-shaped portion is lower than that of the rearward wing-shaped portion and the forward-shaped wing-shaped portion connected thereto. In other words, some forward blade-shaped portions have a large gap with the first casing, so that a larger gap is obtained even in the outer peripheral portion where the number of blades is large. That is, even if solid matter enters the pump, the solid matter can be discharged to the outside of the pump, and there is no clogging by foreign matter.

According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the third swirl type impeller has a third back surface.
The centrifugal impeller has a forward wing-shaped portion having an outlet angle set to about 90 degrees or more with respect to forward rotation on the inner side, and an outlet angle of about 90 degrees on the outer side. A dishwasher having a rearwardly-facing wing-shaped portion set as follows.

When the third centrifugal impeller is turned upside down in the drainage process, the outer portion acts as a forward blade, so that when the washing water in the washing tank is discharged outside the machine and its water level falls, Since the air that has entered the second casing is discharged in a short time, the drainage capacity is high. In addition, in the cleaning step, the outer portion acts as a backward-facing blade-shaped portion, so that the load and the increase in the amount of electricity supplied to the motor are small.

According to a fifth aspect of the present invention, there is provided the dishwasher according to the first to fourth aspects, wherein the rotating shaft of the electric motor is provided in a substantially vertical direction.

According to the first to fourth aspects of the present invention, the pump can be switched between washing and draining by operating the pump with the rotation direction of the electric motor reversed. Here, in particular, by providing the rotating shaft of the electric motor in a substantially vertical direction, the second vortex impeller drains the washing water at the time of inversion. In addition, the first centrifugal impeller has its pressurizing ability stopped as the water level of the washing water drops, and the large operating noise caused by stirring the washing water is reduced. In addition, by reducing the size of a mechanism related to the pump and reducing the projected area of the entire pump, it is possible to increase the cleaning capacity. Furthermore, even if the cleaning water mixed with air enters, it can be pressurized, so that the amount of water supplied in the cleaning process is reduced, and the cleaning water and the object to be cleaned are heated to a predetermined temperature in a short time to obtain cleaning performance. be able to.

[0035]

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1) In FIG. 1, 1 is a washing tank,
2 is a tableware basket for storing items to be washed such as tableware and cooking utensils,
Reference numeral 3 denotes a pump for pressurizing the cleaning water, and reference numeral 4 denotes a cleaning nozzle having an injection port for injecting the cleaning water. 5 is a heater for heating the washing water, 6 is a filter for collecting residual vegetables from the washing water, and 7 is a control device for controlling the operation of the pump 3, the heater 5, and the like.

As shown in FIG. 2, the pump 3 comprises a first casing 12 provided with a first centrifugal impeller 11, a second vortex impeller 13 and a third centrifugal impeller 1.
4 having a second casing 15. Reference numeral 16 denotes a washing water guide communicating with the first casing 12, the second casing 15, and the washing tank 1. Reference numeral 17 denotes a partition plate that is mounted between the first casing 12 and the second casing 15 and forms the washing water guide 16. Reference numeral 18 denotes a suction port that supplies cleaning water to the pump 3, 19 denotes a cleaning discharge port that supplies cleaning water to the cleaning nozzle 4, and 20 denotes a drainage discharge port that discharges cleaning water to the outside of the machine. Reference numeral 21 denotes a motor for driving the first centrifugal impeller 11 and the like.
The control device 7 controls the electric motor 2
1 has a forward / reverse inverting means (not shown) for switching the rotation direction between forward rotation and reverse rotation.

As shown in FIGS. 3 to 5, the first centrifugal impeller 11 has a rearwardly facing blade-shaped portion 11a having an outlet angle set to about 90 degrees or less with respect to forward rotation on the inner side thereof. A second whirlpool impeller 13 having a forward vane-shaped portion 11b having an exit angle set to approximately 90 degrees or more on the outer portion.
Has a blade-shaped portion 13c composed of an arc-shaped portion 13a substantially in contact with the outer peripheral portion with respect to the forward rotation and a linear shape 13b substantially in the radial direction with respect to the reverse rotation. Further, the third centrifugal impeller 14 has a backward-facing vane-shaped portion 14a whose exit angle is set to approximately 90 degrees or less with respect to the forward rotation.

Next, the operation of the dishwasher of this embodiment will be described. The operation method of the cleaning step is basically the same as that of the conventional one, and the description is omitted. A characteristic operation in the present embodiment lies in the operation of the pump 3 in the cleaning process.

In the cleaning step, a predetermined amount of cleaning water is supplied to the cleaning tank 1, and while being heated by the heater 5, the water is pressurized by the pump 3 and is jetted from the cleaning nozzle 4 to remove water from the cleaning object. Remove dirt. The residual vegetables are separated from the washing water by the filter 6 and collected. As the washing process proceeds, the opening area of the filter 6 is reduced depending on the amount of the garbage, so that the washing water is not stably supplied to the pump 3 and air is drawn in.

When the cleaning water is fed to the pump 3 in a state in which bubbles and air are mixed, the first centrifugal impeller 11 that rotates forward has the forward blade-shaped portion 11b.
Since the absolute velocity of the fluid flowing out of the first centrifugal impeller 11 is large, the air is sent from the central portion of the first centrifugal impeller 11 and the outer peripheral portion thereof to the rearward vane-shaped portion 11a. For this reason, the inside rearward vane-shaped portion 11a is filled with the cleaning water having a low mixing ratio of air, and the cleaning water can be pressurized. Then, the bubbles and the cleaning water can be sent to the cleaning nozzle 4. That is, the cleaning water is injected from the cleaning nozzle 4 to obtain the cleaning power.

Since the washing water containing air bubbles can be circulated while being pressurized by the first centrifugal impeller 11, a predetermined amount of washing water to be supplied is equal to that of a general centrifugal pump. Less than in. Therefore, the total heat capacity of the washing water and the tableware is reduced, and this can be heated to a predetermined temperature in a short time by the heater 5 having the same heating capacity as the conventional one. That is, predetermined washing performance and drying performance can be obtained while saving water and saving energy.

The direction of rotation of the electric motor 21 is reversed by washing and draining. During washing, the load W2 of the first centrifugal impeller 11 is large and the load W3 of the second vortex impeller 13 is small. . At the time of drainage, the load W1 of the first centrifugal impeller 11 is small, and the load W4 of the second vortex impeller 13 is large. Further, the third centrifugal impeller 14 is more effective than the load W5 at the time of washing for the load W6 at the time of drainage.
Is big. That is, as shown in FIG. 6, although the load of each impeller fluctuates in the rotation direction, the electric motor 21 receives the load of the total of the load torque of each impeller as the load. Therefore, the load of the electric motor 21 can be set within a certain range without a large change in load under each operating condition. Therefore, the control components of the control device 7 for controlling these operations can be reduced in current and size.

Among the loads by these impellers, the load by the first centrifugal impeller at the time of washing is the largest, so that this has the effect of reducing the load at the time of reverse rotation, thereby leveling the load of both rotations. Is obvious.

It should be noted that the same amount of washing water as before without reducing the amount of washing water supplied can be used for a larger amount of objects to be washed.
The clogging of the filter 6 is less affected and the dishwasher can maintain a high cleaning power.

Depending on the type and amount of dirt, in each of the rinsing steps performed by replacing the washing water, the washing water is stably pressurized even if the washing water is further reduced as compared with the main washing step. And the necessary rinsing effect can be obtained. Of course, an operation in which the amount of water in all the steps is reduced is also possible.

In the drying step, air was blown into the washing tank 1 from outside the machine by a blower (not shown), and the heater 4 was operated intermittently to generate hot air, which was adhered to dishes with the hot air. The humid air in the washing tank 1, which evaporates water droplets, is discharged out of the machine through an exhaust port.

Therefore, assuming that the control device 6 of this embodiment performs heating and rinsing for the same operation time as the conventional one, the temperature of tableware and attached water droplets is reduced by the amount corresponding to the small amount of cleaning water to be heated. Higher than the dishwasher configuration. Therefore, the drying speed is improved, and the drying performance can be improved and the drying time can be shortened. In this way,
The entire operation time including drying can be shortened.

(Embodiment 2) In this embodiment, the basic configuration is the same as that of Embodiment 1, and the shape and operation of the pump 31, especially the first centrifugal impeller 32, are different. explain.

As shown in FIG. 7, the pump 31 includes a first casing 12 provided with a first centrifugal impeller 32,
It has a second casing 15 with a second vortex impeller 33 and a third centrifugal impeller 34. First
A washing water guide 16 communicating with the casing 12, the second casing 15, and the washing tank 1 of the first casing 12;
The configuration of a partition plate 17 and the like mounted between the first casing 15 and the second casing 15 to form the washing water guide 16 is the same.

As shown in FIG. 8, the first centrifugal impeller 32 has a rearward vane-shaped portion 32a having an outlet angle set to about 90 degrees or less with respect to forward rotation on the inner side, and has an outer side on the outer side. It has a forward-facing vane-shaped portion 32b whose exit angle is set to approximately 90 degrees or more. The second swirl type impeller 3
Reference numeral 3 has a blade-shaped portion having an arc shape substantially in contact with the outer peripheral portion with respect to the normal rotation as in FIG. 4 and a linear shape substantially in the radial direction with respect to the reverse rotation. Further, the third centrifugal impeller 34 has an outlet angle of about 90 with respect to the forward rotation as in FIG.
It has a backward-facing wing-shaped portion set to a degree or less.

As a characteristic feature of the present embodiment, the number of blades of the first centrifugal impeller 32 is particularly so arranged that the forward blade-shaped portion 32b is larger than the rearward blade-shaped portion 32a.

In the second embodiment, as in the first embodiment, since the pump 31 can be operated with a small amount of washing water, the heat capacity of the washing water and tableware is reduced, and the pump 31 can be heated to a predetermined temperature in a short time. Thus, predetermined cleaning performance and drying performance can be obtained. Further, in the draining step, the motor is inverted and operated, so that the washing water is drained while being sprayed onto the object to be cleaned, so that the dirt can be discharged. Of course, as in the first embodiment, the outwardly facing vane-shaped portion in the cleaning step exerts a pressurizing ability with a smaller load as the forwardly facing vane at the time of reversal.

In particular, in the forward blade-shaped portion 32b having a large number of blades and a small interval therebetween, the air entering the pump 31 can be discharged in a shorter time. Moreover, since the number of blades is large at the outer portion having a large diameter, the gap of the blade-shaped portion can have a certain size or more from the central entrance to the outer portion. That is, even if solid matter enters the pump 31, there is no clogging due to accumulation of foreign matter at the inlet of the pump 31.

In particular, as shown in FIGS. 9 and 10, a part of the forward blade-shaped portion 32c is connected to the rearward blade-shaped portion 32a, and the height thereof is substantially the same.
The forward wing-shaped portion 32d that is not connected to the backward wing-shaped portion 32a is formed at a low level, so that the gap between the wing-shaped portion and the partition plate 17 has a constant size from the entrance to the exit of the impeller 32A. I can get it.

That is, even if a solid material enters the pump 31 through a second filter (not shown) for preventing a gap or a foreign matter from entering due to an incomplete installation of the filter 6,
The foreign matter is quickly discharged to the outside of the pump 31 by the connected blade-shaped portions 32a and 32c, so that the pump can hardly be clogged by the foreign matter.

It is needless to say that a similar effect can be obtained by forming the blades of the forward-facing blade-shaped portion at least at two levels higher and lower so that the high-level blades are not adjacent to each other. No.

(Embodiment 3) In this embodiment, the basic structure is the same as that of Embodiment 2, but the shape and operation of the pump 35 shown in FIG. 11, especially the third centrifugal impeller 38 are different. Now, this point will be described.

First, similarly to the shape shown in FIG. 3 and FIG. 4 in the first embodiment, the first centrifugal impeller 36 has its inner portion facing backward with the outlet angle set to approximately 90 degrees or less for forward rotation. It has a wing-shaped portion, and has a forward-facing wing-shaped portion with an exit angle set to about 90 degrees or more on the outer side. Also, the second
The vortex impeller 37 has a blade-shaped portion having an arc shape substantially in contact with the outer peripheral portion with respect to normal rotation and a linear shape substantially in the radial direction with respect to reverse rotation.

Next, as shown in FIG. 12, the third centrifugal impeller 38 provided on the back surface of the second vortex type impeller 37 has an outlet angle of about 90 degrees or more with respect to the forward rotation at the inner portion thereof. , And a rearward-facing blade-shaped portion 38b having an outlet angle set to approximately 90 degrees or less on the outer side.

The load of the third centrifugal impeller 38 is small since the outside is the rearwardly facing blade-shaped portion 38b in the washing step. And in the drainage process, it acts as a forward blade at the time of reverse rotation, so when the washing water is drained out of the machine and the water level decreases, the air that has entered the second casing can be exhausted in a short time, and the drainage capacity is increased. high. That is, the amount of residual water in each drainage step of cleaning is small, and the rinsing performance of the object to be cleaned is high. Therefore, the same cleaning performance can be obtained by reducing the amount of water supply in the rinsing step and the amount of water used.

(Embodiment 4) In this embodiment, the basic structure is the same as that of the conventional example, but the structure of the pump 43 is different. Moreover, the basic configuration of the pump 43 is similar to that of the above-described embodiment, except that the rotating shaft of the electric motor 21 is provided in a substantially horizontal direction.

13 and 14, reference numeral 41 denotes a cleaning tank,
Reference numeral 42 denotes a tableware basket for storing items to be cleaned such as tableware and cooking utensils, reference numeral 43 denotes a pump for pressurizing cleaning water, and reference numeral 44 denotes a cleaning nozzle having an injection port for injecting cleaning water. 45 is a heater for heating the washing water, 46 is a filter for collecting residual vegetables from the washing water, and 47 is a control device for controlling the operation of the pump 3, the heater 5, and the like.

In the fourth embodiment, the pump 43 can be accommodated in the lower part of the washing tank 41 by providing the rotating shaft of the electric motor 21 in a substantially horizontal direction. Therefore, the tableware basket 42 has a large projected area and is easy to use.

It should be noted that this pump 43 is
The operation of performing the washing and draining by switching the rotation direction according to a is the same as in the other embodiments, and thus the description is omitted.

Here, in order to efficiently perform the draining process with the rotating shaft of the electric motor 21 provided in a substantially horizontal direction,
The pump 43 is provided with a first centrifugal impeller
, A second casing 49a on which the second vortex type impeller 49 is mounted, and a washing water guide 50 communicating with the first casing, the second casing 49a, and the washing tank 41. , First casing 48a
And a water draining hole 50a communicating the washing water guide portion 50 with the cleaning water guide portion 50.

The drain hole 50a has an effect of guiding the washing water of the first casing 48a to the washing water guide portion 50 and the second casing 49a in the draining process. This is to reduce the noise caused by the mixing sound of the washing water by the centrifugal impeller 48.

As in the first to third embodiments, the motor 2
When the first rotating shaft is provided in a substantially vertical direction, the second swirl type impeller drains the washing water at the time of reverse rotation, and the first centrifugal type impeller stops the pressurizing ability as the transition decreases. At the same time, the noise of stirring the residual water during drainage is reduced. Further, the size of the mechanism can be reduced, and in particular, the projected area of the mechanism can be reduced. Thus, it goes without saying that the storage capacity of the object to be cleaned can be increased particularly in the height direction.

Further, in the above embodiment, the motor 21
As the rotation control means, phase control and inverter control are also possible. Moreover, if the electric motor 21 is a DC brushless motor, it is needless to say that the rotation speed can be controlled in a wider range, and various operation methods for saving water and reducing time can be realized.

[0070]

Since the present invention is configured as described above, it has the following effects.

According to the first aspect of the present invention, the tableware for storing the object to be cleaned, the cleaning tank in which the tableware is housed, the cleaning nozzle having the injection port for spraying the cleaning water, and the cleaning water by rotating the electric motor. A pump for pressurizing the electric motor, and a forward / reverse reversing means of the electric motor, wherein the pump is provided with a first casing for discharging cleaning water to a cleaning nozzle by a first centrifugal impeller, and a pump by a second vortex impeller. A second casing for discharging washing water to the outside,
The first centrifugal impeller is provided with a rearward vane-shaped portion having an outlet angle set to approximately 90 degrees or less with respect to a predetermined rotation direction on an inner portion thereof, the washing water guide portion communicating with the casing and the washing tank. It has a forward wing-shaped portion with an exit angle set to approximately 90 degrees or more on the outer portion, and the second vortex type impeller has a circular arc shape almost in contact with the outer peripheral portion with respect to normal rotation and with respect to reverse rotation. The radially linear wing-shaped part, the absolute flow of fluid flowing out of the forward-facing wing-shaped part when the cleaning water is pumped into the pump with air bubbles and air mixed. Due to the high speed, the air
To the outer periphery of the centrifugal impeller. For this reason, the inside rearward vane-shaped portion is filled with the washing water having a small mixing ratio of air, and the washing water can be pressurized. Then, air and cleaning water can be sent to the cleaning nozzle, and the cleaning water is jetted to rotate the cleaning nozzle normally.

As described above, the washing water containing air bubbles can be circulated while being pressurized by the first centrifugal impeller.
The amount of cleaning water to be supplied can be reduced as compared with a general centrifugal pump. As a result, the heat capacity of the washing water and tableware is reduced, and this can be heated to a predetermined temperature in a short time. That is, there is provided a dishwasher capable of achieving predetermined washing performance and drying performance while saving water and saving energy.

The direction of rotation of the motor is reversed between washing and drainage. However, during washing, the load on the first centrifugal impeller is large and the load on the second vortex impeller is small. During drainage, the load on the first centrifugal impeller is small and the load on the second vortex impeller is large. That is,
The motor can be set within a certain range without a significant change in load under each operating condition. Therefore,
The components of the control device for controlling these operations can be reduced in current and size.

According to the second aspect of the present invention, in the first aspect of the present invention, the number of blades of the first centrifugal impeller is arranged such that the front blade shape portion is larger than the rearward blade shape portion. As in the first aspect of the present invention, the pump can be operated with a small amount of washing water, so that the heat capacity of the washing water and tableware is reduced, and this can be heated to a predetermined temperature in a short time, and a predetermined cleaning performance and Drying performance can be obtained. Furthermore, by inverting and operating the electric motor in the drainage process, the drainage is performed while the cleaning water is sprayed onto the object to be cleaned, so that the dirt can be discharged. In the cleaning process, the outwardly facing vane-shaped portion exerts a pressurizing ability with a smaller load as a forward vane when it is turned over.

In particular, in a forward-facing blade-shaped portion having a large number of blades and a small interval therebetween, the air entering the pump can be discharged in a shorter time, and the cleaning performance is stabilized. Moreover, since the number of blades is large at the outer portion having a large diameter, the gap of the blade-shaped portion can have a certain size or more from the central entrance to the outer portion. That is, even if solid matter enters the pump, clogging due to accumulation of foreign matter at the inlet of the pump does not occur.

According to the third aspect of the present invention, in the first or second aspect of the present invention, a part of the forward wing-shaped portion is connected to the rearward wing-shaped portion and the height thereof is substantially the same. The forward wing-shaped portion that is not connected to the wing-shaped portion has its height formed at a low level. Since it is lower than the forward-facing vane-shaped portion connected thereto, the gap between the casing and the vane-shaped portion always has a constant size from the entrance to the exit. That is, even if a larger solid matter enters the pump, it is discharged to the outside of the pump, so that a dishwasher free from clogging with foreign matter for a long period of time can be provided.

According to a fourth aspect of the present invention, in the first to third aspects of the present invention, a third centrifugal impeller is provided on a back surface of the second vortex type impeller, and the centrifugal impeller is provided at an inner portion thereof. A forward wing-shaped portion whose exit angle is set to approximately 90 degrees or more with respect to the forward rotation, and a rearward-facing wing-shaped portion whose exit angle is set to approximately 90 degrees or less on the outer portion. Thus, the load of the third centrifugal impeller is small because the outside is the rearwardly facing blade-shaped portion in the washing step. Moreover, in the drainage process, when the washing water is drained and reduced, the air entering the second casing can be quickly discharged when the washing water is drained and reduced, thereby providing a dishwasher having a high drainage capacity. it can.

According to the fifth aspect of the present invention, in the first to fourth aspects of the present invention, in particular, by providing the rotating shaft of the motor in a substantially vertical direction, the motor is operated by reversing the rotating direction of the motor. It can be done by switching between washing and drainage. At the time of reversal, the second swirl type impeller drains the washing water,
The centrifugal impeller stops its pressurizing ability as the water level decreases. It is possible to reduce the size of the mechanism unit by the projected area and increase the cleaning capacity. Furthermore, since the washing water mixed with air can be pressurized, the amount of supplied water can be reduced, and the washing water or the object to be washed can be heated in a short time to obtain a dishwasher capable of obtaining a predetermined washing performance. .

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a dishwasher according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the pump of the embodiment.

FIG. 3 is a plan view of a first centrifugal impeller in the pump according to the embodiment.

FIG. 4 is a plan view of a second vortex type impeller in the pump of the embodiment.

FIG. 5 is a plan view of a third centrifugal impeller in the pump according to the embodiment.

FIG. 6 is a chart showing the rotation direction of the pump of the embodiment and the load on each impeller.

FIG. 7 is a sectional view of a main part of a pump according to a second embodiment of the present invention.

FIG. 8 is a plan view of a first centrifugal impeller in the pump according to the embodiment.

FIG. 9 is a sectional view of a main part of a pump according to another embodiment of the present invention.

FIG. 10 is a plan view of a first centrifugal impeller in the pump.

FIG. 11 is a sectional view of a main part of a pump according to a third embodiment of the present invention.

FIG. 12 is a plan view of a third centrifugal impeller in the pump of the embodiment.

FIG. 13 is a sectional view of a main part of a dishwasher according to a fourth embodiment of the present invention.

FIG. 14 is a sectional view of a main part of the pump of the embodiment.

FIG. 15 is a sectional view of a main part of a conventional dishwasher.

FIG. 16 is a sectional view of a main part of the cleaning pump in the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Washing tank 2 Tableware basket 3 Pump 4 Washing nozzle 5 Heater 6 Filter 7 Control device 11 1st centrifugal impeller 11a Backward blade shape part 11b Forward blade shape part 13 2nd vortex type impeller 14 Third centrifugal impeller 21 Motor 43a Forward / reverse inversion means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Takashi Miyauchi 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Takeshi Inada 1006 Kadoma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. Terms (Reference) 3B082 BD01 BD02 BF01 BF04 BF05

Claims (5)

[Claims] 1. A dish basket for storing an object to be washed, a washing tank containing the same, a washing nozzle having an injection port for ejecting washing water, a pump for pressurizing the washing water by rotation of an electric motor, and the electric motor The pump has a first casing for discharging cleaning water to a cleaning nozzle by a first centrifugal impeller during normal rotation, and a second vortex-type impeller for reverse rotation when the pump rotates reversely. A first casing, a first casing, a second casing, and a washing water guide communicating with the washing tank. The first centrifugal impeller rotates with respect to forward rotation. The second swirl type impeller has an outer periphery provided with a rearward vane-shaped portion having an outlet angle set to approximately 90 degrees or less and a frontward vane-shaped portion having an exit angle set to approximately 90 degrees or more. Touches the part A dishwasher provided with a wing-shaped portion consisting of an arc shape and a substantially radial straight line shape. 2. The dishwasher according to claim 1, wherein the number of blades of the first centrifugal impeller is arranged so that the forward blade-shaped portion is larger than the rearward blade-shaped portion. 3. A part of the forward-facing wing-shaped portion of the outer portion is connected to the rearward-facing wing-shaped portion, and the height thereof is substantially the same, and the height of the other forward-facing wing-shaped portions is formed at a low level. Item 3. A dishwasher according to item 1 or 2. 4. A third centrifugal impeller is provided on the back surface of the second vortex type impeller, and the third centrifugal impeller has an outlet angle of about 90 degrees or more on its inner portion with respect to forward rotation. The dishwasher according to any one of claims 1 to 3, wherein the set forward wing-shaped portion is provided with a rearwardly directed wing-shaped portion having an exit angle set to approximately 90 degrees or less on an outer portion thereof. 5. The dishwasher according to claim 1, wherein the rotating shaft of the electric motor is provided in a substantially vertical direction.