JPH034860A - Hot water for bathing circulating pump driving circuit for bubble generating bathtub - Google Patents

Abstract

PURPOSE:To prevent a bathing person, which is interposed in a route, from getting an electric shock by smoothing the rise and fall of an output waveform from an inverter. CONSTITUTION:A time constant circuit, which is composed of a resistor(r) and a capacitor(c), is provided on the switching signal input part of a switching element 45 and the rise and fall of a switching signal to be inputted to the switching signal input part are made smooth. Thus, by smoothing the rise 47 and the fall 48 of an output voltage 46 to be outputted from the switching element 45 and making them almost trapezoidal waves, a high frequency output included in an alternative current output is decreased. In such a manner, the level of the high frequency component included in the output waveform of an inverter 13 is lowered and the high frequency current to leak to a bathing place can be decreased. Accordingly, even when a motor part 21 is not completely grounded, the route of the high frequency current can be formed through the human body of the bathing person between the motor part 21 and the ground of a commercial power source 37 and there is no danger for the bathing person to get the electric shock caused by the flow of the high frequency current in hot water for bathing.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a bath water circulation pump drive circuit for a bubble-generating bathtub.

(b) Conventional technology In the past, a bath water suction flow path and a bath water forced flow flow path were interposed between the bathtub body and a bath water circulation pump installed outside the bathtub body. While opening the end of the channel into the bathtub body,
BACKGROUND ART There is a bubble-generating bathtub that is configured to have an air intake part connected to the bathwater forced flow path so as to spray bubble-mixed bathwater into the bathtub body.

Recently, by driving the motor of the bath water circulation pump via an inverter, the number of rotations of the motor can be varied, and the discharge pressure and amount of the pump can be controlled. In order to make the inverter smooth and quiet, there is an inverter in which the output waveform is PWM-modulated at a high modulation frequency so that the average value of the output waveform approximates a sine waveform.

(c) Problems to be Solved by the Invention In such an inverter, the gain of the switching elements used in the switching circuit is extremely large in order to increase the power conversion efficiency, and therefore, the gain of the switching elements used in the switching circuit is extremely large. As a result, the output voltage rises and falls extremely quickly.

Therefore, the AC power output from the inverter is
It contains a large number of high-frequency components, and this high-frequency component leaks into the bath water through capacitive coupling between the motor windings and the field, and if the motor is not properly grounded, it may harm the bather. There was a risk of electric shock when the person came into contact with a grounded item.

In addition, one pole of a commercial power supply is always grounded to the ground, and when a bather comes into contact with a grounded item, the high frequency current generated in the inverter is transmitted to the inverter motor windings = (capacitive coupling) - the motor's windings. It leaks through the path of magnetic field → Bomboo bath → human body → grounded item → earth → commercial power source ground → wiring from commercial power source to inverter → inverter, causing electrocution to bathers who are intervening in the above path. become.

(d) Means for Solving the Problems In the present invention, a bath water suction channel and a bath water forced flow channel are interposed between the bathtub body and a bath water circulation pump installed outside the bathtub body. The end of the hot water forced flow channel is opened in the bathtub main body, and an air intake part is connected to the bath water forced flow channel,
The bath water circulation pump is configured to eject bath water mixed with air bubbles into the bathtub body, and by driving the motor section of the bath water circulation pump via an inverter, the rotation speed of the bath water circulation pump can be changed. It is an object of the present invention to provide a bath water circulation pump drive circuit for a bubble generating bathtub, which is characterized in that the output waveform of an inverter has a gradual rise and fall.

(E) Functions and Effects According to the present invention, even if the grounding of the motor section, etc. is incomplete, the rise and fall of the inverter's output waveform is made gentler, and the inverter's output waveform is improved. By reducing high frequency components, it is possible to prevent bathers from receiving electric shocks.

(l\) Example An example of the present invention will be explained based on the drawings. In Figs. 1 and 2, (^) indicates a bubble-generating bathtub according to the present invention, and the same bubble-generating bathtub (A) is the bathtub body (1) and the bath water circulation pump installed outside the bathtub body (1) (
2), there is a bath water suction flow path (3) and a bath water forced flow path (4).
), the terminal end of the bath water forced flow channel (4) is branched into six, and the foot side, dorsal side, and ventral side are provided at each end of the branched bath water forced flow channel (4). Side jet nozzle (5) (5), (6) (
6), (7) (7) are connected and connected, and the same foot side, dorsal side, and ventral side jet nozzles (5) (5) (B) (6) (7) (7
), the bath water forced flow channel (4) is opened into the bathtub body (1), and the bath water forced flow channel (4) is provided with an air intake section (
8) are connected to the bathtub body (1
) is configured to eject inside.

Further, a rim (9) of a predetermined width is formed on the periphery of the bathtub body (1), and an air intake portion (8) is provided in the rim (9).

In addition, a pump protective case (10) is attached to the outside of the bathtub body (1).
), and the above-mentioned circulation pump (2) and filter (
II), a control device (C), an inverter (I3),
It houses these accessory devices.

As shown in Fig. 3, the circulation pump (2) has a motor section (
21) and a pump section (22), the motor section (21) is a three-phase induction motor, and a field (24) is arranged in the motor casing (23) to (24
), and an alternating current voltage is applied to the winding (25) to generate a rotating magnetic field, and a cylindrical rotor (26) is inserted into the motor casing (23) on the output shaft ( 27
), and the rotation speed of the output shaft (27) can be adjusted by changing the rotation speed of the rotating magnetic field using an inverter (13), which will be described later.

The pump part (22) has inside the pump casing (28),
An upper impeller chamber (29) that communicates with the bath water suction channel (3) and the filter (11), and a lower impeller that communicates with the bath water suction channel (3) and the forced bath water flow channel (4). The upper and lower impellers (31 and 32) are rotatably arranged in the upper and lower impeller chambers (29 and 30), respectively, and are interlocked and connected to the output shaft (27). are doing.

Further, as shown in the figure, an insulating plate (33) made of synthetic resin is interposed between the motor casing (23) and the pump casing (28), and the motor casing (23) is connected to the motor casing (23) via the field (24). ) is prevented from leaking into the bath water via the pump casing (28), and the upper and lower impellers (31) and (32) are integrally constructed from a synthetic resin material with electrical insulation properties. Then, the central shaft (34) of the impeller (31) (32') is extended upward, and an output shaft insertion hole (35) is bored at the upper end of the coaxial shaft (34). ) to the output shaft (2) of the motor section (21).
7) is inserted and fixed, and a mechanical seal (36) is interposed between the upper part of the casing (28) and the central shaft (34) to prevent water leakage. 34), the pump part (22) and motor part (
21) are electrically insulated.

The inverter (13), as shown in FIGS. 4 and 5,
The single-phase AC 100V from the commercial type RI (37) is converted to DC 200V by the rectifier circuit (38) and smoothing circuit (P), and is supplied to the switching circuit (39). , the output frequency of the inverter (13) can be arbitrarily changed by controlling the control device (C) via the inverter control circuit (12).

Therefore, under control from the control device (C), the rotation speed of the circulation pump (2) can be changed to change the discharge pressure and discharge amount of the pump (2).

In addition, by PWM controlling the output waveform of the inverter, the average value of the output waveform is approximated to a sine waveform,
The motor section (21) rotates smoothly.

In addition, in order to increase the power conversion efficiency, the gain of the switching element (45) used in the switching circuit (39) is made extremely large.
), the voltage rises and falls very quickly in response to the switching signal input from the control device (C).

Therefore, the AC power output from the inverter (13) contains a large number of high frequency components, and these high frequency components are transmitted to the field (24) of the motor section (21).
If the grounding of the motor section (21) is incomplete, the motor section (
21) and the ground of the commercial power source (37), a high-frequency current path is created through the body of the bather, and the high-frequency current described above may flow through the bathing water and cause an electric shock to the bather. be.

Therefore, in the present invention, as shown in FIG. 5, a resistor (r) is connected to the switching signal input section of the switching element (45).
A time constant circuit consisting of a capacitor (C) and a capacitor (C) is provided to slow down the rise and fall of the switching signal input to the switching signal input section, thereby increasing the output voltage (4B) output from the switching element (45). By making the rise (47) and fall (48) of can be reduced.

In this way, the level of high-frequency components included in the output waveform of the inverter (I8) is lowered to reduce the high-frequency current leaking into the bath water, thereby preventing electric shock.

Incidentally, since the impedance of capacitive coupling becomes smaller as the frequency becomes higher, the greater the attenuation in the high frequency band as shown in FIG. 7, the greater the effect.

In addition, in this embodiment, each jet nozzle (5) (6)
(7) has the same configuration, and will be explained with reference to FIG. 8, taking the foot side jet nozzle (5) as an example.

The foot side jet nozzle (5) includes a cylindrical nozzle body (70) fitted into the side wall of the bathtub body (1), and a nozzle body (70) fitted into the side wall of the bathtub body (1).
0), a valve body (72) provided behind the valve seat (71), a nozzle motor (Ml) that moves the valve body (72) forward and backward, and the valve It consists of a swingable throat (73) provided in front of the seat (71).

The nozzle body (70) has a bath water flow path (4) at the rear thereof.
), and the valve body (72) is brought into contact with and separated from the valve seat (71) to adjust the amount and pressure of hot water spouted from the nozzle (5). Open the air inlet (74) that communicates with the inlet (8), and then open the valve seat (71).
Due to the ejector effect of the bath water that has passed through the bathtub body (1
) is configured so that air is mixed into the bath water that spouts out.

The nozzle motor (old) consists of a stepping motor attached to the rear wall of the nozzle body (70) and a ball screw that converts the rotational motion of the motor into linear motion and transmits it to the valve body (72). A valve position sensor (75) for detecting the position of the valve body (72) is disposed at the rear end.

As shown in Figure 9, the control device (C) includes a microprocessor (MPU) and an input/output interface (+) (
0) and a memory (M) that stores a control program, and the input interface (1) includes a temperature sensor (1) and a pressure sensor ( p) and the operation of the bubble generating bathtub (^) installed on the operation panel (14), adjust the intensity of the hot water spout from each spout nozzle, and specify the spout form of the bath water. It is connected to various switches (50), (50), etc. that specify the nozzle from which to spout bath water, and each spout nozzle is controlled by the input from these sensors (t) (p) and the switch group. (5) (5) (8) (6) (7
) (7), the rotational speed of the circulation pump (2), etc., so that various types of hot water can be spouted.

Further, as shown in Fig. 1, the operation panel section (14) provided on the air intake section (8) has an infrared receiving section (
17) to receive control signals from the remote controller (1B).

The remote controller (16) has an operation panel section (1
4) Various switches arranged in <50) (50)...
By operating the switch group, an infrared signal set for each switch is transmitted from the infrared irradiation section (15), and the same infrared signal is transmitted to the infrared rays of the operation panel section (14). By receiving the information at the receiving unit (17) and inputting it to the input interface (+) of the control device (C), the control operation from the bather is accepted, and the bath water is spouted in a manner corresponding to each of the above switches. It is configured as follows.

[Brief explanation of the drawing]

FIG. 1 is an overall perspective view of a bubble-generating bathtub having a bathwater circulation pump drive circuit according to the present invention, FIG. 2 is an explanatory diagram showing the structure of the same bathtub, and FIG. Fig. 4 is a block diagram showing the configuration of the inverter, Fig. 5 is a switching circuit diagram, Fig. 6 is an output waveform graph from the switching circuit, and Fig. 7 shows the frequency spectrum of the output of the present invention and the conventional technology. The graph, FIG. 8 is a sectional view of the bath water spouting nozzle, and FIG. 9 is a block diagram showing the configuration of the control device. Air bubble generation bathtub Bathtub body Bathwater circulation pump Bathwater suction flow path Bathwater forced flow flow path Air intake section (13): Inverter <21): Motor section

Claims (1)

[Claims] 1) A bath water suction channel (3) is provided between the bathtub body (1) and a bath water circulation pump (2) installed outside the bathtub body (1).
and a forced bath water flow path (4).
The terminal end is opened into the bathtub body (1), and an air intake part (8) is connected to the bathwater forced flow channel (4), so that the bathwater mixed with air bubbles is drawn into the bathtub body (1). By driving the motor section (21) of the bath water circulation pump (2) via an inverter (13), the rotation speed of the bath water circulation pump (2) can be changed. A bath water circulation pump drive circuit for a bubble generating bathtub (A), characterized in that the output waveform of an inverter (13) has a gradual rise and fall.