JP2003139344A - Drain pump for air conditioner and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a pressure sensor for detecting the water level inside a drain pan for controlling a drain pump and to prevent malfunction of the pressure sensor according to the setting of a position for installing the pressure sensor. SOLUTION: This drain pump for the air conditioner is provided with a pump part 14 rotatably incorporating a vane member in its inside and a DC motor 13 for driving the vane member. This drain pump has a constitution of attaching a pressure detecting part 20 for detecting a drain water head to the pump part so that the pressure sensor 20 can precisely measure the water head of the drain water with less contamination. This constitution can grasp a lift 40 of the installed drain pump by the rotation speed based on the data of the pressure sensor 20 and add a voltage corresponding to the rotation speed so as to drain water at the optimal conditions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a drain pump (drainage pump) for draining drain water collected in a drain pan (water tray) of an air conditioner and a drain pump control method.

[0002]

2. Description of the Related Art During air-conditioning operation of an air conditioner, a large amount of dew condensation occurs on the surface of the indoor heat exchanger, which is drained and drips.
Generally, a drain pan (water tray) is provided at the bottom of the indoor heat exchanger. Then, in order to drain the drain water collected in the drain pan, a drain pump (drain pump)
Is provided, and the drain pump discharges the drain out of the room.

An example of such a drain pump is disclosed in Japanese Patent Laid-Open No. 2001-123977. This will be briefly described with reference to FIG. 12. In FIG. 12, reference numeral 01 is a pump chamber formed in the pump body 02, reference numeral 03 is an inlet port, 04 is an outlet port, and 05.
Indicates a motor. Reference numeral 06 denotes a drain water guide portion, and inside the drain water guide portion 06, a shaft 07 extends toward the axial direction and has a plurality of blade members whose inner ends are located away from the shaft 07. An impeller 08 is attached, and a plate-shaped auxiliary blade 09 is attached below the shaft 07 along the axial direction. The lower end of each blade member is connected by a donut-shaped drain guide plate, a drain guide surface 010 having a hollow portion is formed between the blade member and the auxiliary blade 09, and the free surface formed by the pump body is a blade. It is possible to suppress the disturbance by members and gradually reduce the generation of bubbles, noise, and vibration. A device shown in FIG. 11 has been proposed as a drainage pump for an air conditioner equipped with such a pump. Note that the pump shown in FIG. 11 has a configuration partially similar to that of the embodiment of the present invention described later, and therefore FIG.
1, the same members as those shown in FIGS. 1 to 9 are denoted by the same reference numerals, and the description thereof is omitted here.

Further, as a drain pump operation control device, a device described in Japanese Patent Application Laid-Open No. 6-221596 is known. This will be explained with reference to FIG.
Reference numeral 003 indicates 0 drain water accumulated in the drain pan 002.
1 shows a drain pump for discharging 01, and this drain pump 003 is an upper position detecting thermistor 008.
Further, the operation control device is adapted to be operated by the drain water level signal detected by the lower position detecting thermistor 009. In FIG. 13, reference numeral 004 is a suction port, 005 is a discharge port, 006 is a drain pipe, 007 is a drain port, 020 is a wave breaker in which an upper position detecting thermistor 008 and a lower position detecting thermistor 009 are present, and 021 is a control. Shows a container.

[0005]

The operation control device for the drain pump as shown in FIG. 13 uses the thermistor to detect the water level in the drain pan. Therefore, if the water surface in the drain pan vibrates, the water level cannot be detected. There is a problem that it becomes accurate.

In addition, a float type switch which is provided with a float in the drain pan and operates when the water level in the drain pan rises, and a pressure sensor (switch) in which an object such as a pipe is arranged from above are known. There is. However, it is a problem of dust and dirt that both of them rotate around the installation place. That is, when dust (such as sand) is deposited on the bottom of the drain pan, it may operate as if it were without water.

Further, the float type switch and the pressure sensor (switch) arranged from the upper part do not move or become blocked when floating dust adheres to the float that moves under pressure or the pipe part that introduces pressure. However, there is a problem in that it is difficult to control them well with those detection signals.

Further, when the drainage pump is operating in the normal mode at the rated rotation speed (voltage), the drainage is drained more and more, but the drain water level of the drain pan is lowered, the discharge pressure is lowered, and the drainage pump becomes in a balanced state. Even when there is no power, the rotation speed of the drainage pump is constant, extra power consumption is used, and noise and vibration are still generated.

The present invention uses the pressure sensor to detect the water level in the drain pan for its control in the drain pump, and devises the position where the pressure sensor is installed, so that the above-mentioned problems of the pressure sensor system are encountered. It is intended to eliminate. That is, according to the present invention, by providing a pressure sensor in the pump body, the discharge port, or the drainage pipe, it is possible to accurately measure the head pressure of drain water with less dust, and the data detected by the pressure sensor is used. Based on the above, the drainage pump installed in the air conditioner can be drained under optimum conditions by grasping the head of the drain pump installed based on the pump rotation speed and reapplying the voltage corresponding to that rotation speed. And its control method.

[0010]

According to a first aspect of the present invention, there is provided a drainage pump for an air conditioner, comprising: a pump portion rotatably incorporating a blade member therein; and a DC motor for driving the blade member. A pressure detecting unit for detecting a drainage water head pressure is directly attached to the pump unit and is connected to a pipe so that the drainage water head pressure can be monitored. According to a second aspect of the present invention, in a drainage pump for an air conditioner, a pump unit rotatably incorporating a blade member therein,
A direct current motor for driving the vane member, and a pressure detection unit for detecting a drainage water head pressure is directly attached to a side surface of the pump unit or a discharge unit, or a pipe connected to a discharge port of the pump unit. The head pressure of drainage water can be monitored to solve the problem. According to a third aspect of the present invention, in a drainage pump for an air conditioner, a pump unit that rotatably houses a blade member therein and a DC motor for driving the blade member are provided, and a pressure detection unit is provided inside the motor. The pressure receiving port of the built-in pressure detection unit is connected to the pump unit or the discharge unit of the drain pump or the pipe connected to the discharge port of the pump, and the drainage head pressure can be monitored to solve the problem. As a means. A fourth aspect of the present invention is the drainage pump for an air conditioner according to any one of the first to third aspects, wherein the internal pressure of the drainage pump is monitored by monitoring a change in internal pressure that occurs during operation of the drainage pump. The supply voltage is made variable and the drainage pump is operated under an appropriate amount of drainage as a means for solving the problem. The invention of claim 5 is any one of claims 1 to 3.
In the drainage pump for an air conditioner according to the item, by monitoring a change in internal pressure generated during operation of the drainage pump, the head can be determined from the internal pressure, thereby varying the rotation speed of the drain pump, It is a means of solving the problem that the water is drained at an appropriate amount. Claim 6
The present invention is the drainage pump for an air conditioner according to any one of claims 1 to 3, wherein a decrease in the rotation speed of the drain pump due to a rise in the water level of the drain pan is detected in standby mode 1. The means for solving the problem is to return the rotation speed of the drain pump to the rated rotation speed. The invention of claim 7 is the drainage pump for an air conditioner according to any one of claims 1 to 3, wherein in the standby mode 1,
When the increase in the discharge pressure due to the rise in the water level of the drain pan is detected, the rotation speed of the drain pump is returned to the rated rotation speed, which is a means for solving the problem.

According to the first to third aspects of the present invention, since the pressure sensor is provided in the pump body or in the discharge port or the drain pipe, the head pressure of the drain water with less dust can be accurately measured. Based on that data, the drainage pump (drain pump) installed head can be grasped by the number of revolutions, and the voltage corresponding to the number of revolutions can be reapplied to perform drainage under optimal conditions. Is possible.

According to the fourth aspect of the present invention, the supply voltage is varied so that the internal pressure is maintained (the balance lift is maintained) while monitoring the internal pressure. In other words, if the internal pressure decreases, the supply voltage is, for example, 400 cm
Addition of a voltage equivalent to ³ / min enables drainage with little loss. As described above, the invention of claim 4 is characterized in that only the internal pressure is monitored, and the drain pump is controlled by voltage control without monitoring the rotation speed. In the conventional pump, for example, when a pump whose working head is set to 100 cm is installed at a sufficient place with a head of 50 cm, a head difference of 50 cm occurs. This is directly added to the drainage volume, but in reality it is not added as it is, and more than the drainage volume of the capacity determined by the shape of the pump becomes a loss, and the loss is the heat generation of the motor and the increase in the watering noise. Such a drawback can be solved by the invention of claim 4.

According to the fifth aspect of the present invention, since the relational expression between the head and the required number of revolutions is input to the microcomputer or the like, if the head is known, the water can be drained at that number of revolutions. That is, the drain pump is controlled by reliably grasping the internal pressure and the rotation speed.

In the sixth aspect of the invention, the control is performed only by the change of the rotation speed, and in the seventh aspect of the invention, the control is performed by the increase of the internal pressure.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. 1 is a sectional view showing a drain pump according to a first embodiment of the present invention, FIG. 2 is a sectional view showing a drain pump according to a second embodiment of the present invention, and FIG. 3 is a third embodiment of the present invention. Sectional drawing which shows a drain pump, FIG. 4 shows the 4th of this invention.
Sectional drawing which shows the drain pump which concerns on embodiment, FIG. 5 is sectional drawing which shows the drain pump which concerns on 5th Embodiment of this invention, FIG. 6 is sectional drawing which expands a part of FIG. 5, and FIG. 4 is a sectional view showing a state of the drain pump when draining, FIG. 8 is a sectional view showing a state where drainage of the drain pump of FIG. 4 is completed and balanced, and FIG. 9 is a rotational speed of the drain pump of FIG. FIG. 10 is a flow chart showing the control method of the drain pump, which is a sectional view showing the state in which the apparatus is lowered to enter the standby mode.

The first embodiment will be described with reference to FIG. The pump body 14 is directly attached to the DC motor 13 attached to the attachment portion 1 via the attachment plate 17. A suction port 12 of the drain pump is opened to the drain pan 2, and an L-shaped drainage pipe 5 is connected to the discharge port 11. Reference numeral 15 is a pump lid, 16 is a DC motor 13
Is a power line (including a signal line), 22 is a drain in the drain pan 2, and 30 is a stable water level (suction water level) of the drain.

In the drain pump of the first embodiment, the pressure sensor 20 for detecting the drain water head pressure of the drain pump is
It is directly attached to the pump body 14. Reference numeral 18 indicates a power supply line (including a signal line) of the pressure sensor 20. As the pressure sensor 20, for example, the one shown in FIG. 14 is suitable.

That is, the pressure sensor 20 includes a joint body 204 that forms a flow path by the inflow port 204, the outflow port 203, and the diaphragm 203, and a substrate support body that holds the peripheral edge of the diaphragm 203 on the joint body 204 and fixes it. 205
A pressure receiving plate 206 fixed to the upper surface of a diaphragm 203 slidably provided in the substrate support 205, a permanent magnet 207 provided on the sliding surface of the pressure receiving plate 206, and a position opposite to the permanent magnet 207. The fixed Hall element 208 and the main spring 2 that presses the pressure receiving plate 206 toward the diaphragm 203 side.
09, and a water level sensor using a Hall element that applies a spring force against the main spring 209 to the diaphragm 203 is used.

The second embodiment will be described with reference to FIG. In the drain pump of the second embodiment, the pressure sensor pressure receiving port 19 is branched to the discharge port 11 of the drain pump, and the pressure sensor 20 is attached to the pressure sensor pressure receiving port 19.

In the drain pump of the third embodiment shown in FIG. 3, the pressure sensor 20 is attached to the horizontal end of the L-shaped drain pipe 5.

In the drain pump of the fourth embodiment shown in FIG. 4, the branch pipe 19 is provided at the rising portion of the L-shaped drain pipe 5.
The pressure sensor 20 is attached via A.

In the drain pump of the fifth embodiment shown in FIG. 5, the pressure sensor 20 is built in the motor 13. In the case of this example, a discharge pressure detecting tube 52 is provided between the discharge port 11 of the drain pump and the pressure sensor 20 in order to transmit the drain water head pressure to the pressure sensor 20. Figure 6
In the figure, reference numeral 19a is a tube 52 and a pressure sensor 20.
The reference numeral 19b indicates a pressure sensor pressure receiving port serving as a connecting portion for connecting to the tube, and the reference numeral 19b indicates a discharge pressure exclusive port serving as a connecting portion between the tube 52 and the discharge port 11.

In each of the above embodiments, the pressure sensor 20 is mounted at a position where the head pressure of the drain water with less dust can be accurately measured. In addition, by grasping the head 40 where the drainage pump (drain pump) is installed by the number of revolutions and reapplying a voltage corresponding to the number of revolutions, it is possible to perform drainage under the optimum conditions.

The operation will be described by taking the drain pump shown in FIG. 4 as an example. FIG. 7 shows a state in which the pump is operated and an appropriate amount of drainage is being performed (normal mode). In addition,
The dimension "A" is the mounting position of the pressure sensor 20 (the vertical dimension from the bottom of the drain pan 2 to the center of the pressure sensor 20).
Indicates.

If the operation shown in FIG. 7 is continued, the drain water level in the drain pan 2 will eventually drop, and the drain will not be drained. This state is usually called "balanced state". FIG. 8 shows the drain pump in a balanced state. At this time, in the conventional motor, since the motor operates at the same voltage as in the normal mode, drainage is completed, the balance is reached, the water level is lowered, and the rotation speed is increased, resulting in wasted energy consumption. However, in the case of this embodiment, when the balance state is reached, control for lowering the rotation speed of the motor 13 is performed. As a result, the discharge pressure of the drain pump decreases, and the standby lift 44 (= A + B) becomes lower than the balance lift 42 of FIG. 8 as shown in FIG.
The state shown in FIG. 9 is called "standby mode 1". That is, the standby mode 1 is a state in which the rotation speed of the drain pump is lower than that required for drainage suitable for the use head.

When the drain water level rises during the standby mode 1, the discharge pressure rises in accordance with the change. When that state is detected by the pressure sensor 20, control is performed to increase the rotation speed of the motor 13 to the specified rotation speed, and the drain pump returns to the normal mode. The above control is performed by the microcomputer. The control by the microcomputer will be described in detail below.

Next, the above control will be described with reference to the flow chart shown in FIG. An "ON" signal is given to the drain pump drive motor (DC motor) 13 (step S1). Upon receipt of the "ON" signal, the drain pump rotates at the rated rotation speed, that is, it operates in the normal mode to drain an appropriate amount of water (step S2).

During this operation, the pressure sensor 20 detects the drain water head pressure (discharge pressure) of the drain pump and measures the pump rotation speed (step S3). The detection value and the rotation speed are monitored for a certain period of time (for example, 10 to 20 minutes, which is meaningless in a short time state check) (step S4).

The drainage water head pressure (discharge pressure) detected by the pressure sensor 20 and the data of the pump rotation speed are taken into the microcomputer, and the drainage water head pressure (discharge pressure) and the pump rotation speed are monitored for a certain period of time. , That tendency (whether the drain accumulates or does not accumulate (decrease) is determined (step S
5). If it is determined that the drain tends to accumulate, the process returns to step S4, and if it is determined that the drain does not accumulate, the process proceeds to step S6. When it is determined that the fuel does not accumulate, the discharge pressure does not change, the rotation speed increases, and a stable state is achieved. Further, since this data is stored in the microcomputer, after the second time, the process jumps from step S5 to a standby mode 1 of step S9 described later.

When the state where the drain is not accumulated continues, the rotation speed (voltage) is lowered while monitoring the discharge pressure (step S
6). When the discharge pressure starts to decrease by this control, the rotation speed (voltage) is fixed to that condition (step S7), and this rotation speed condition is stored in the microcomputer (step S8).
Then, in this state, the rotation speed and the discharge pressure are monitored (step S9). This state corresponds to "standby mode 1". During this standby mode 1, the state of drain accumulation is always detected (step S10), and this state, that is, the standby mode 1 is maintained, while the state of no accumulation is detected. That is, step S9 and step S10 are repeatedly executed.

In step S10, when the water level in the drain pan rises, a decrease in the number of revolutions and an increase in the discharge pressure are detected, the process returns to step S2, the drain pump returns to the rated number of revolutions, operates in the normal mode, and drains a proper amount of water. Is performed. This state is called "standby mode 2". After that, the same steps as described above are sequentially executed. As described above, in this embodiment, not the rated rotation speed but the appropriate rotation speed according to the lift or a voltage commensurate with the rated rotation is selected according to the determination result of the lift.

The rotation speed of the DC motor can be detected by using, for example, a "DC motor with pulse output", and the rotation speed N of the DC motor is proportional to the voltage V and N is the torque T. Inversely proportional. Further, when V is constant, the current I has a characteristic proportional to T (see FIGS. 15 to 1).
7), it is possible to control the drain pump as described above by utilizing such characteristics. 18, 1
9 is a drain pump power supply 100, an air conditioner microcomputer 10
1, an example of a wiring diagram of the pressure sensor 20 and the drainage pump is shown.

Next, an actual example will be given. Table 1 shows an example of installation at a lifting height of 75 cm, and at the time of balancing, by changing the rotation speed from the normal mode to the standby mode,
The pressure head is lowered by 13 cmH2O. When water is supplied to the drain pan in this state, the head (discharge pressure) increases due to the pressure. In the example of Table 1, the standby mode 1 is changed to the standby mode 2 and the lift due to the pressure is 75
Trying to return to cmH2O. That is, the microcomputer 10 sends an electric signal that the load is increased, the rotation speed is decreased, and the water level is increased.
1, the microcomputer 101 processes so as to switch to the normal mode, and the drainage pump operates in the normal mode.

[0034]

[Table 1]

As described above in detail, according to the present invention, the head to be used can be confirmed when the drain pump is operated by measuring the head pressure (discharge pressure) during drainage. As a result, the air conditioner itself can be checked. The condition is that the signal indicating the start of drainage indicates the pressure rise of the pressure detection unit, and then the discharge pressure in the drainage state where the rotation speed does not change for a certain period can also be read as the use head.
After that, drainage is completed and the pressure does not change, but the number of rotations increases and the load decreases (the drain pan has less water)
However, it will be in a balanced state and a more accurate lift can be confirmed. It is possible to check whether the piping at the time of unit installation to check this lift is not used as it is without looking at the piping.
Also, even if there is a situation in which the beam in the attic must be overcome several times due to installation (trap state), it can be confirmed that there is no problem as long as it is within the specified lifting range.

As described above, by measuring the discharge pressure, an appropriate number of rotations is given based on the installed state of the drain pump and its data, and the drain water can be drained.

[0037]

As described above, according to the present invention, even if a problem occurs in the middle of the piping on the drain side, it is not possible to take measures such as stopping the air conditioner or displaying an abnormality. By monitoring the pressure, it can be determined that the discharge pressure abnormality that has occurred after installation is that the pipe is clogged or the pipe is disconnected. In other words, if the pipe is clogged, the discharge pressure will reach a cut-off lift far higher than the use lift, and if the pipe in the middle is disengaged, it will be lower than the use lift when setting the unit. Also, there is a point where the discharge pressure starts to decrease when the rotation speed is lowered during balancing.If the drain pump water level rises while the drain pump is operating at a rotation speed below this point, the discharge pressure will change in response to that change. Rises. Sensing that condition,
If the rotation speed is increased to the specified rotation speed to return to the normal mode, and the movement at the point where the discharge pressure starts to fall is the “standby mode”, by repeating these two modes, the normal mode When draining water, but when it is not necessary, you can suppress power consumption in standby mode,
Since the number of rotations is reduced, noise can be further reduced and vibration can be reduced.

Further, by simultaneously monitoring the discharge pressure and the rotation speed of the drainage pump, if the rotation speed of the drainage pump is detected but the discharge pressure is not measured, the blade member is damaged or removed. It is possible to detect the failure of the drainage pump itself when it is considered. Furthermore, when the discharge pressure is higher than the drainage pump speed confirmed in the normal mode, but the discharge pressure is higher (corresponding to the deadline lift), the drain pipe is clogged or damaged. Can be detected.

[Brief description of drawings]

FIG. 1 is a sectional view showing a drain pump according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a drain pump according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a drain pump according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a drain pump according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view showing a drain pump according to a fifth embodiment of the present invention.

FIG. 6 is an enlarged cross-sectional view of a part of FIG.

7 is a cross-sectional view showing a state of the drain pump of FIG. 4 during drainage.

FIG. 8 is a cross-sectional view showing a state where drainage of the drain pump of FIG. 4 is completed and balanced.

9 is a cross-sectional view showing a state in which the drain pump of FIG. 4 is lowered in rotation speed to enter a standby mode.

FIG. 10 is a flow chart showing a control method of the drain pump.
It is

FIG. 11 is a cross-sectional view showing a conventional drain pump.

FIG. 12 is a sectional view showing a conventional drain pump.

FIG. 13 is a sectional view showing a conventional drain pump.

FIG. 14 is a cross-sectional view of an example of a pressure sensor.

FIG. 15 is a characteristic diagram showing the relationship between the rotation speed N of the DC motor and the voltage V.

FIG. 16 is a characteristic diagram showing a relationship between the rotation speed N and the torque T of the DC motor.

FIG. 17 is a characteristic diagram showing the relationship between the current I and the torque T of the DC motor.

FIG. 18 is an example of a wiring diagram of the present invention.

FIG. 19 is another example of the wiring diagram of the present invention.

[Explanation of symbols]

1 mounting part 2 drain pan 13 motor 14 Pump body 16 power lines (including signal lines) 18 Power line for pressure sensor (including signal line) 20 Pressure sensor 40 heads 42 Balance lift 44 Standing head

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takashi Nakajo             535 Sasai, Sayama City, Saitama Prefecture Sagimiya Co., Ltd.             Tokoroyama Office F-term (reference) 3H020 BA07 CA01 CA05 CA07 DA03                       EA02                 3L050 BD05 BF02                 3L060 AA02 AA03 AA08 CC15 CC19                       EE01

Claims (7)

[Claims] 1. A pump unit having a blade member rotatably incorporated therein, and a DC motor for driving the blade member,
A drainage pump for an air conditioner, wherein a pressure detection unit for detecting a drainage water head pressure is attached to the pump unit so that the drainage water head pressure can be monitored. 2. A pump unit having a vane member rotatably incorporated therein, and a DC motor for driving the vane member,
A pressure detection unit for detecting a drainage water head pressure is directly attached to a side surface of the pump unit, a discharge port unit, or a pipe connected to the discharge port of the pump unit so that the drainage water head pressure can be monitored. A drainage pump for air conditioners. 3. A pump unit having a vane member rotatably incorporated therein, and a DC motor for driving the vane member,
A pressure detector is built in the motor, and a pressure receiving port of the pressure detector is connected to a pump unit or a discharge port of the drain pump, or a pipe connected to a discharge port of the pump to discharge water. A drainage pump for an air conditioner, which is capable of monitoring pressure. 4. The drainage pump is operated under an appropriate drainage volume by varying the supply voltage of the drainage pump by monitoring a change in internal pressure generated during the operation of the drainage pump. Any one of claims 1 to 3
Item 4. A method for controlling a drainage pump for an air conditioner according to Item. 5. The head can be determined from the internal pressure by monitoring the change in the internal pressure generated during the operation of the drainage pump, whereby the rotation speed of the drain pump can be varied and the drainage can be performed at an appropriate amount. Claim 1 characterized by
The control method of the drainage pump for an air conditioner according to any one of 1 to 3. 6. When a decrease in the rotation speed of the drain pump due to a rise in the water level of the drain pan is detected in a state where the rotation speed of the drain pump is lower than the rotation speed of the drain pump (standby mode 1) required for drainage that conforms to the use head, the drain pump is detected. The method for controlling a drainage pump for an air conditioner according to claim 1, wherein the rotation speed of the pump is returned to the rated rotation speed. 7. In the standby mode 1, when an increase in the discharge pressure due to a rise in the drain pan water level is detected,
The method for controlling an air conditioner drainage pump according to claim 1, wherein the rotation speed of the drain pump is returned to a rated rotation speed.