JP4627824B2 - Detachable liquid level detector for automatic operation of submersible electric pumps - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a detachable liquid level detector for automatic operation of a submersible electric pump.
[0002]
[Prior art and its problems]
Conventionally, the liquid level detection for automatic operation of submersible electric pumps has adopted a direct detection method in which the control liquid level and the sensor position are set at the same level, and the pump motor start liquid level detection and stop liquid level detection Usually two upper and lower liquid level sensors are used. Therefore, in the float type liquid level sensor, the installation interval between the upper and lower sensors must be changed or the lead wire lead-out length must be adjusted each time according to the control range of start / stop of the pump motor, and When the control width is large, the float lead wire length that can cover the control width is required. However, if the lead wire lengthens, the float tilting operation becomes unstable and the internal electrical switching mechanism is turned on and off. Switching may not be performed properly and lead wires may be entangled.
[0003]
In addition, there is a system in which the ON signal for starting the pump motor is given by the liquid level sensor, and the stop signal is stopped after the operation is continued for a certain time by the timer after the OFF signal is detected by the sensor. Since the timer is set, the time-up position does not necessarily coincide with the desired stop position that the user wants to stop, and liquid level control with high accuracy cannot be performed.
[0004]
OBJECT OF THE INVENTION
The object of the present invention is that even if the control width of start / stop is large, it is not necessary to lead out the float lead wire long, the float tilting operation is stable, and the liquid level control with high accuracy without causing the lead wire to be entangled. It is an object of the present invention to provide a detachable liquid level detector for automatic operation of a submersible electric pump, which can be performed by a single float type liquid level sensor.
[0005]
[Structure of the invention]
In the detachable liquid level detector for automatic operation of an underwater electric pump according to the present invention, an automatic operation circuit of a pump motor is housed in a holding body of a liquid level sensor, and the base of the holding body is a power cord lead on the upper surface of the submersible electric pump. Formed in a mounting portion that is overlapped with the outlet and attached / detached by the fixing tool, a vertical lead hole is formed in the mounting portion to lead out the lead line from the automatic operation circuit, and the lead hole is provided on the power cord outlet The lead wire from the automatic operation circuit is connected to each core wire from the power cord and the lead wire from the motor side so as to be separable by a connector, and power is supplied from above the outlet hole via the watertight structure. In the detachable liquid level detector for automatic operation of the submersible electric pump configured to mount the holding body base on the outlet according to the state in which the cord is led out, the automatic operation circuit is equipped with a microcomputer. A single float type that has a control circuit section and an opening / closing section, and the liquid level sensor transmits a detection signal by switching the contact of the internal electric switching mechanism ON-OFF by the tilting movement of the float accompanying the fluctuation of the liquid level This is a liquid level sensor. When the liquid level rises, the pump motor is activated by the activation liquid level detection signal generated by the upward tilting operation of the float type liquid level sensor. Based on the time required for the detection of the switching liquid level detection signal, the time required to descend to a predetermined stop liquid level is calculated, and the operation of the pump motor is limited to the calculated time. The circuit is set so that the pump motor stops when time is up.
[0006]
【Example】
Hereinafter, description will be made with reference to the drawings of the embodiments.
[0007]
P is an automatic submersible electric pump to which the liquid level detector of the present invention is attached, 1 is a holding body in which the liquid level sensor 2 is led out from the tip, and the pump motor M is automatically operated using the hollow part. The circuit 3 is built in, and the base 1a of the holding body 1 is formed in a mounting portion that overlaps the power cord outlet 4 on the upper surface of the automatic submersible electric pump P, and a lead wire from the automatic operation circuit 3 is provided in the mounting portion. A lead-out hole 6 is vertically provided for guiding the power cord 5 and guiding the power cord 5. The automatic operation circuit 3 has a control circuit portion 3a and an opening / closing portion 3b mounted on a microcomputer, and the liquid level sensor 2 is an internal electric opening / closing mechanism (not shown) by tilting movement of the float accompanying the fluctuation of the liquid level. This is a float type liquid level sensor that sends a detection signal when the contact point is turned on and off. For example, when the liquid level rises in the pump installation tank, the float is tilted upward at the starting liquid level L1 to detect the ON signal. As a result, the pump motor M is activated, and when the liquid level in the tank is lowered by the draining action of the pump P and reaches the switching liquid level L2, the float is tilted to detect the OFF signal. The time required until the detection of the OFF signal after the start-up, that is, the time t1 required for the liquid level to drop from the start-up liquid level L1 to the switching liquid level L2 by the drainage action of the pump P is counted. 1 is calculated, a time t2 required to descend to a predetermined desired stop liquid level L is calculated, and the operation of the pump motor M is continued with the calculated time t2 as a limit. The circuit is set to stop. Accordingly, the drainage action by the pump P is continued for a certain time after the OFF signal is detected by the liquid level sensor 2, and the drainage action by the pump P is also stopped at the desired stop liquid level L.
[0008]
For it is equipped with the present invention liquid level detection device to the non-automatic water electric pump P 'as shown in FIG. 1, is separated from the lead line of each core wire from each motor side from the power cord 5, the power cord 5 2 is extracted to bring the state shown in FIG. 2 into alignment, the outlet hole 6 provided vertically in the holding body 1 shown in FIGS. 3 and 4 is aligned with the power cord outlet 4, and the power cord 5 once extracted is attached. Used again, the lead wire from the automatic operation circuit 3 is connected to each core wire from the power cord 5 and the lead wire from the motor side in a separable manner by a connection tool 7 such as a connection terminal or a terminal block, and is led out. If the outside of the holder base 1a is fixed by a fixing tool 9 such as a tightening bolt in a state where the power cord 5 is led out from above the hole 6 through the plug-like watertight structure 8, the tip portion is lateral. It is equipped with a liquid level detector in a protruding state, and non-automatic water The middle electric pump P ′ is converted to the automatic submersible electric pump P shown in FIGS.
[0009]
When the automatic submersible electric pump P equipped with the liquid level detector of the present invention is used as a non-automatic type, the base 1a of the holding body 1 is removed from the outlet 4 as shown in FIG. while connected detachably by the connecting device 7 to the lead wire of the core wires from the motor side from the non-automatic shown in FIG. 1 when caused to derive the power cord 5 through the watertight structure 8 from outlets 4 The submersible electric pump P ′ is configured.
[0010]
【The invention's effect】
According to the liquid level detector of the present invention, the liquid level detection for the operation control of the pump can be performed by a single float type liquid level sensor and can be produced at a low cost. Thus, there is no need to change the installation interval between the upper and lower liquid level sensors according to the control width or to adjust the lead wire lead length, and even if the start / stop control width is large, the float lead wire There is an effect that it is not necessary to derive for a long time, the tilting motion of the float is stable, and the liquid level can be controlled with high accuracy without causing the tangling of the lead wire.
[0011]
Furthermore, it can be used immediately as an automatic submersible electric pump simply by attaching the liquid level detector of the present invention to a ready-made non-automatic submersible electric pump, and it can be restored to the original non-automatic submersible electric pump by removing it. There is an advantage that you can also.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view of a main part of a non-automatic submersible electric pump to which a liquid level detector according to the present invention is attached.
2 is a longitudinal sectional side view of a main part showing a state in which a power cord is extracted from the non-automatic submersible electric pump of FIG. 1. FIG.
FIG. 3 is a longitudinal side view of a main part of the liquid level detector of the present invention.
FIG. 4 is a plan view of the liquid level detector of the present invention.
FIG. 5 is a longitudinal sectional side view of a main part of an automatic submersible electric pump configured by mounting the liquid level detection tool of the present invention from the state of FIG. 2;
6 is an external side view of the automatic submersible electric pump shown in FIG. 5. FIG.
FIG. 7 is a block diagram showing a configuration of an automatic submersible electric pump equipped with the liquid level detector of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Holding body 1a Base 2 Float type liquid level sensor 3 Automatic operation circuit of pump motor 3a Control circuit part 3b Opening and closing part 4 Power supply cord outlet 5 Power supply cord 6 Lead-out hole 7 Connector 8 Watertight structure 9 Fixing tool M Pump motor

Claims (1)

The automatic operation circuit of the pump motor is accommodated in the holding body of the liquid level sensor, and the base of the holding body is formed on a mounting portion that is overlapped with the power cord outlet on the upper surface of the submersible electric pump and is attached and detached by a fixing tool. The lead-out hole for leading out the lead wire from the automatic operation circuit is provided vertically in the section, the lead-out hole is overlapped with the power cord outlet, and the lead wire from the automatic operation circuit is connected to each core wire from the power cord. and connected detachably by a respective connector to the lead wire from the motor side, and by a state of being derive the power cord through the watertight structure from the outlet hole so as to mount the holder base in the pull-out Prompt In the detachable liquid level detector for automatic operation of the submersible electric pump configured as described above, the automatic operation circuit has a control circuit section and an opening / closing section mounted on a microcomputer, and the liquid level sensor is a fluctuation of the liquid level. This is a single float type liquid level sensor that sends a detection signal when the contact of the internal electrical switching mechanism is switched on and off by the tilting movement of the float. When the liquid level rises, the float type liquid level sensor moves upward. The pump motor is activated by the activation liquid level detection signal by, and the time required for the detection of the switching liquid level detection signal by the downward tilting operation of the liquid level sensor due to the liquid level descent after the pump motor activation is determined in advance as a reference. The circuit is set so that the time required to descend to the predetermined stop liquid level is calculated, the pump motor is continuously operated up to the calculated time, and the pump motor is stopped when the time is up. A detachable liquid level detector for automatic operation of a submersible electric pump.

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