JPS59148901A - Electric insulation device by small-sized transformer - Google Patents

Abstract

PURPOSE:To reduce a control circuit at its size and weight by connecting a sensor to the secondary side of small-sized transformers. CONSTITUTION:Current is supplied from an AC power supply 1 to a heater 7 for a carpet through a contact 8 and DC voltage for a driving circuit is obtained through a power supply transformer AD/DC converter 13, a resistor 10, a smoothing capacitor 11. A load power supply controlling circuit 4 and a sensor voltage detecting circuit 5 and a sensor signal output circuit 6 are connected to the DC voltage. When the temperature of the heater 7 is detected by a sensor 9 or the like, the contact 8 is controlled so as to be turned on/off to control the temperature of the carpet. When the temperature is detected, the sensor 9 is connected to the secondary side of the transformers 14, 15 and a detecting circuit 5 and an output circuit 6 are connected to the primary side, so that the carpet body is insulated from an AC power line.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrical isolation device using a small transformer for insulating a sensor and a control circuit.

2. Description of the Related Art Conventional Structures and Problems Conventionally, it has been important to make control circuits for home appliances smaller and lighter.

The conventional electrical insulation device as described above will be described below with reference to the drawings.

FIG. 1 shows a control circuit using a conventional electrical isolation device. In FIG. 1, 1 is an AC 2/Z power source, and 2 is a power transformer, which serves to electrically insulate between the secondary fl111 circuit side A2 and the primary AC power source side A1. 3 is an AC-DC conversion circuit which converts the alternating current (AC) voltage stepped down by the transformer 2 into a direct current (NC) voltage.

4 is a load energization control circuit that controls power supply to the load. 5 is a sensor voltage detection circuit that converts the sensor state into voltage, and controls the load energization control circuit 4 according to the voltage. A sensor signal output circuit 6 supplies a sensor 9 signal, and this signal is input to the sensor detection circuit 5 via the sensor 9. 7 is a load, which in this conventional example is a heater built into a carpet or the like.

8 is a contact that is connected by the load energization control circuit 4;

9 is a sensor as already mentioned.

The operation of the conventional electrical insulation device configured as described above will be described below.

First, in this conventional example, the load 7 and the sender 9 constitute an electric carpet main body. When the carpet switch is turned on, contact 8 closes and AC power 1 is sent to load (heater) 7.
1- is supplied, and the carpet 31.- becomes warm. The sensor 9 detects the temperature of this carpet. Here, there is a risk of electric shock if a hook or a metal that can cause an electric shock is inserted into the carpet body, so the sensor side A2 needs to be insulated from the AC power source side A1. Therefore, the AC power supply 1 is insulated by the power transformer 2 and stepped down to create a DC voltage by the AC-DC conversion circuit. When the signal is passed through the sensor, the magnitude of the signal changes depending on the temperature of the carpet, and this change is detected by the sensor voltage detection circuit 5, and the contact 8 is controlled via the load energization control circuit 4. , which works to keep the carpet temperature constant.

However, in the conventional configuration as described above, the power supply l.
Since Lance 2 was used, a transformer with a large capacity was required, which had the drawbacks of being bulky and heavy. For this reason, it has been desired to make the i-lance smaller and to make the control circuit smaller and lighter.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, the present invention provides an electrical insulating device using a compact lance, which can reduce the size and weight of a control circuit by eliminating the power supply lance.

Structure of the Invention In order to achieve this object, the compact transformer of the present invention is used.
The electrical insulating device is on the power supply l/lance side! - Eliminates the run and connects a small transformer to the sensor, making it possible to isolate between the power line and the sensor where there is a possibility of electric shock.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows an electrical insulating device using a small lance according to an embodiment of the present invention.

In FIG. 2, numerals 1, 4 to 9 have the same structure as in FIG. 1. 10 is a step-down resistor, 11 is a smoothing capacitor, and 10.11 produces a low voltage direct current. 14.
15 is a small transformer, which transmits the signal from the page 5 sensor signal output circuit and electrically insulates the carpet body and the AC power line.

Next, to explain the operation of this device, first, a high voltage DC power source is shaped by the AC-DC conversion circuit 13 connected to both ends of the AC power source 1, and the voltage is stepped down by the resistor 10 and the smoothing capacitor 11. A DC power source is created to drive the circuit. Next, considering the case where the contact point 8 is closed, when AC voltage is applied to the heater 7 and the temperature of the carpet body rises, the signal output from the sensor output circuit 6,1 will be transmitted to the small transformer 14. is applied to the sensor via
This signal changes depending on the temperature of the carpet body.

Furthermore, the signal 17 is transmitted via the sensor 9 to the small transformer 15.
The sensor voltage detection circuit 5 determines the magnitude of the signal, controls the load energization control circuit 4, and connects the contact 8.
The carpet opens and closes depending on the temperature of the carpet itself.

As described above, according to the apparatus of this embodiment, as described above: -
The control circuit can be miniaturized by insulating the pet body and the AC power line via a small 61, 2-type transformer.

Light weight can be achieved.

In this embodiment, signals were transmitted using two small transformers, but as shown in FIG. 3, it is also possible to realize an electrically isolated circuit using one small transformer.

Effects of the Invention As described above, the device of the present invention can isolate the AC power line from the load by connecting the secondary side of the small transformer to the sensor, thereby reducing the size of the control circuit.

It can be lightweight, and its practical value is great.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a conventional electrical insulating device, Fig. 2 is a circuit diagram of an electrical insulating device according to an embodiment of the present invention, and Fig. 3 is a circuit diagram of an electrical insulating device according to another embodiment of the present invention. be. 1- AC power supply, 4 Load energization control circuit, 5- Sensor voltage detection circuit, 6 Sensor signal output circuit, 7
Load resistance, 8 contacts, 97 Hage sensor, 14.15 Transformer.

Claims (1)

[Claims] An electrical isolation device using a small transformer, which has a configuration in which the secondary side of a small transformer is connected to both ends of the sensor, and the sensor signal output circuit and sensor voltage detection circuit are connected to the primary side of the small transformer.