JP2869283B2 - Current transformer for current detection of air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current transformer for detecting a load current of an air conditioner comprising an indoor unit and an outdoor unit, in particular, a current flowing through a compressor.

[0002]

2. Description of the Related Art As an air conditioner, there is generally known a separated type comprising an indoor unit A and an outdoor unit B as shown in FIG. The indoor unit A has a load 2 such as a fan motor, a flap motor, or a microcomputer for control in addition to the heat exchanger. The outdoor unit B has a fan motor and a control unit in addition to the heat exchanger, the compressor, and the pressure reducing device. A load 3 such as a microcomputer for use is mounted.

In such an air conditioner, the current flowing through the compressor when the load increases or when the load is overloaded increases. If this current exceeds the designed capacity of the compressor, the electric motor in the compressor may be burned out due to overcurrent. For this reason, the operation of the compressor is controlled so that the current flowing through the compressor does not exceed the set value.

[0004]

Conventionally, a current transformer (CT) 4 has been used as a current detector for detecting the operating current of an air conditioner as shown in FIG. The load current of the unit B is detected. One or two turns of a power supply wire to the load 3 are wound on the primary side of the current transformer 4, and the output current on the secondary side caused by the inductive coupling is controlled by a resistor 5, a diode 6, and a smoothing capacitor 7. The current is rectified, smoothed, divided by the resistors 8a and 8b, input to the A / D port of the microcomputer 9 as an appropriate DC voltage, and the microcomputer 9 determines whether or not the operating current has reached a set value. In the conventional outdoor unit B, the current transformer 4 is mounted on the same circuit board as the resistor 5, the diode 6, the microcomputer 9 and the like so that the signal line can be short, and a waterproof measure is taken by covering the whole with a pack. In addition, since a relatively thick wire is used as the power supply wire to the load 3, it is quite difficult to route such a power supply wire in the unit, and there is a problem that the length of the wire becomes long. .

[0005] The present invention has been made in view of the above points, and has as its object to make it easy to route a power supply wire to a load inside an outdoor unit of an air conditioner, and to make the wire short.

[0006]

According to the present invention, in order to achieve the above object, a load current detecting current transformer of an outdoor unit of an air conditioner is separated from a circuit board for controlling the operation of the outdoor unit. The power supply wire for supplying power to the compressor in the unit is mounted at a position where the path of the power supply wire is not regulated.

[0007]

According to the present invention, it is easy to pass a relatively thick power supply wire through the primary side of the current transformer, and the wire can be shortened.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a current detecting current transformer according to the present invention. The current transformer 4 is such that a ferrite ring-shaped core (not shown) is wrapped in a casing 42 on a resin base 41 and fixed by bonding or the like, and a secondary winding of the current transformer is provided below the core. Is wound around the bobbin 43a. Although not shown, the primary winding of the current transformer is passed through the space A by winding one or two turns around the core at the upper part of the core. The secondary output of the current transformer 4 is taken out via a wire 43b connected to the secondary winding. Screw holes 44 for mounting the current transformer 4 inside the outdoor unit B are provided at both ends of the pedestal 41.

Next, the mounting position of the current transformer will be described with reference to FIGS.

FIG. 2 shows a state where the front panel of the outdoor unit B of the air conditioner is removed. In the outdoor unit B, two fans 11a and 11b are provided on the upper surface of the case 10, and an electrical box is provided in a space C below the fans 11a and 11b. This electrical box is shown in greater detail in FIG. Two compressors 12a are located at the bottom of the electrical box.
And 12b are provided with piping and wiring. An accumulator and other auxiliary parts are also provided.

FIG. 3 shows mainly electric wiring of the electrical box.

The electric box includes an iron plate 15 fixed to the case 10 of the outdoor unit B by welding or screws, a power terminal plate 16 to which an external three-phase power line is connected, a fuse 17, and compressors 12a and 12b. Relay 18 for controlling power supply to power supply, step-down transformer 19, electrolytic capacitor 20 for power supply circuit, circuit board 21
Are attached with screws. The circuit board 21 is laid out at a position distant from the power supply terminal board 16, and control electric components such as the resistor 5, the diode 6, the smoothing capacitor 7, and the microcomputer 9 are attached to the circuit board 21. The circuit components in the electrical box are electrically connected to each other by wires 22. In a certain portion, some wires 22 are bound to form a harness.

The current transformer 4 according to the invention is arranged on the plate 15 approximately halfway between the power terminal plate 16 and the power relay 18. The current transformer 4 is mounted by using the screw holes 44 of the pedestal 41.
And screw it into the plate 15. Current transformer 4
Is attached to the power supply wire 2 from the power supply terminal plate 16.
Since the wire 3 is extending toward the power relay 18, the power supply wire 23 can be easily passed through the current transformer 4 as the primary winding of the current transformer 4, thereby facilitating the wiring.

The installation of the current transformer 4 is not limited to the plate 15, but may be any fixing member in place of the plate 15. Further, the mounting position of the current transformer 4 is not limited to the position of the present embodiment. The circuit components of an air conditioner vary depending on the model. Is preferably arranged.

[0016]

As described above, according to the present invention,
The current transformer for detecting the load current of the outdoor unit of the air conditioner is not mounted on the same circuit board for device control as the microcomputer etc., so it is mounted at a position away from the circuit board and near the path of the power supply wire inside the unit This makes it easier to route the wires and makes the wires shorter.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of a current detecting current transformer according to the present invention.

FIG. 2 is a front view of the air conditioner with a front panel removed.

FIG. 3 shows circuit components and electric wiring of an electric box mounted inside the air conditioner shown in FIG.

FIG. 4 is an example of a current detection circuit of the air conditioner.

[Explanation of symbols]

 4 Current Transformer 41 Base 9 Microcomputer 10 Case 15 Plate 16 Power Terminal Plate 18 Power Relay 21 Circuit Board 22 Wire 23 Power Supply Wire

Claims (1)

(57) [Claims] 1. An indoor unit having an indoor heat exchanger, and an outdoor unit having a compressor, an outdoor heat exchanger, and a decompression device, wherein the indoor heat exchanger, the compressor,
In a current transformer for detecting a current flowing through the compressor of the outdoor unit in an air conditioner having a refrigeration cycle in which an outdoor heat exchanger and a pressure reducing device are connected by a refrigerant pipe, the current transformer is connected to the outdoor unit. A current detecting current transformer for an air conditioner, which is separated from a circuit board that controls the operation of the air conditioner and is attached to a position in the outdoor unit that does not regulate the path of a power supply wire for supplying power to the compressor. vessel.