JPS5839417Y2 - electricity meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a watt-hour meter, and particularly to improvements that facilitate overhaul of three-phase and single-phase three-wire watt-hour meters.

Generally, after a watt-hour meter has been used for a valid period of certification (seven years for regular meters, five years for precision grade and above), it is overhauled and re-certified before use.

The number of overhauled and reused electricity meters reaches several hundred meters each year, far exceeding the number of new ones.

For this reason, it is important for power meters to have original functionality and reliability as well as ease of overhaul.

Recent three-phase three-wire and single-phase three-wire power meters are designed to be smaller and lighter, and to reduce the weight of the rotor and improve the wear characteristics of the bearings. The mainstream is a system in which a driving element is provided.

Figure 1 is a top view showing the arrangement of the drive element and brake magnet of a conventional electricity meter of this type, where 1 is the base, 2 is the glass cover, and 3
4 is a rotating disk, 4 is a driving element, and 5 is a brake magnet.

Because of this structure, during assembly, drive elements are attached to the left and right sides of the main frame that fixes the main parts necessary to configure the electricity meter, and the rotating disk is driven from the front of the main frame. After inserting the element into the center of the gap between both voltage and current cores, attach its upper and lower bearings to the upper and lower parts of the main frame, respectively, to support the rotating disk, and then insert the element from the front as well. The brake magnet is attached to the main frame, and finally the weighing device is attached to the main frame.

For this reason, in the overhaul at the expiration of the certification period,
Rotating parts such as the measuring device, bearings, and rotating disks are cleaned and parts that are subject to high wear are replaced. However, in conventional electricity meters with the structure described above, unless the braking magnet is removed, the rotating disks will be damaged. cannot be removed.

On the other hand, the braking magnet must apply braking torque to the rotating disk of the drive element that is commensurate with the rotation of the rotating disk at a predetermined speed.

However, it is difficult to obtain the necessary precision in the magnetic force of the brake magnet due to variations in the material and dimensions of the magnet itself, as well as variations in the yoke and magnetizing field.

In addition, even if the magnetic force of the magnet has the required precision, due to variations in the drive torque of the drive element and variations in the relative position with the rotating disk, it is difficult to rotate the braking torque with the required precision. It is difficult to feed the disc.

For this reason, the brake magnet is equipped with a heavy load adjustment device that can adjust the magnetic force (braking force) after being attached to the main frame.

For this reason, removing the brake magnet during overhaul, as in conventional watt-hour meters, not only requires effort for removal and installation, but also adds to the trouble of adjustment.

The present invention provides three-phase and single-phase three-wire power meters that can be easily overhauled by easily removing the rotating disk and bearings without removing the braking magnet as in conventional power meters. The purpose is to provide.

Therefore, in the present invention, the braking magnet is inserted into the rear part of the main frame made of non-magnetic material so as to sandwich the rotating disc, and a heavy load adjustment iron plate is placed in contact with the top surface of this braking magnet via the non-magnetic material. The structure is equipped with a heavy load adjustment device that adjusts the heavy load by moving the heavy load adjustment screw threaded onto the main frame, thereby making it possible to remove the rotating disk and bearing without removing the brake magnet. We achieved the desired goal by creating a power meter that made it possible.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 2 to 4.

FIG. 2 is a top view showing the arrangement of a driving element and a braking magnet of a watt-hour meter according to an embodiment of the present invention, and the same parts as in FIG. 1 are given the same reference numerals.

It is shown that the brake magnet 5 is disposed on the rear side of the rotary disk 3 when viewed from the front glass cover 2 of the electricity meter.

FIG. 3 shows the present invention in which the drive element 4 in FIG. 2 is omitted.
FIG. 2 is a side view showing the main parts of the electricity meter of the example.

The main frame 6 that holds the main components is made of a non-magnetic material such as die-cast aluminum.

A pair of brake magnets 5a and 5b are respectively inserted into the main frame 6 at positions sandwiching the peripheral edge of the rotating disk 3 at the rear of the main frame 6, and are placed opposite to each other with a gap between the rotating disks 3. There is.

The surface of the braking magnet 5a on the upper side of the rotating disk 3 opposite to the disk is thinly covered with aluminum.

The heavy load adjustment iron plate 7 is provided in close contact with the aluminum surface of the brake magnet 5a, and as shown in FIG.
, 5b are formed by a flat plate portion of equal length and a pair of bent portions 7a and 7b bent at right angles.

A U-shaped groove is formed in the upper center of this bent portion.

The heavy load adjustment screw 8 is screwed into the front part of the main frame 6, and its non-threaded portion is connected to the U of one bent portion 7b of the heavy load adjustment steel plate 7.
The stepped narrow diameter portion fits into the groove of the other bent portion 7a and engages with it.

The heavy load adjusting iron plate 7 and the adjusting screw 8 form a heavy load adjusting device.

The brake magnets 5a and 5b are each magnetized as shown in FIG.

Therefore, since the heavy load adjustment iron plate 7 forms a bypass of the magnetic path of the brake magnet 5a, when the adjustment iron plate 7 is moved along the aluminum surface of the brake magnet 5a and moved closer to or away from the brake magnet 5a, the adjustment iron plate 7 As a result, the magnetic flux passing through the rotating disk 3 is adjusted and the braking torque applied to the rotating disk 3 is adjusted to adjust the error of the watt-hour meter.

The rotating disk 3 is pivotally supported by a lower bearing 9 fitted into the main frame 6 and fixed with screws, and an upper bearing 10 screwed into the main frame 6 and fixed.

The measuring device 11 integrates the rotation of the rotary disk 3 and displays the measured electric energy in units of kWh, and is attached to the main frame 6.

In the watt-hour meter of the present invention and embodiment configured as described above, by rotating the heavy-load adjustment screw 8 with a screwdriver from the front of the watt-hour meter, the heavy-load adjustment iron plate 7 is moved by the adjustment screw 8. As a result, the magnetic flux passing through the rotating disk 3 is adjusted and the braking torque applied to the rotating disk 3 is adjusted, thereby making it possible to adjust the error due to the heavy load of the watt-hour meter.

Also, since the braking magnets 5a and sb are arranged on the rear side of the rotating disk 3, the weighing device 11, which is cleaned and repaired at the time of overhaul, the upper and lower bearings 9° 10, and the rotating disk 3 are connected to the braking magnet 5a, 5b, the heavy load adjusting iron plate 7, and the adjusting screw 8 can be removed without removing them, eliminating the need for readjustment, reducing labor for removing and installing, and facilitating overhaul.

As detailed above, according to the present invention, the rotating disk can be easily removed without removing the braking magnet and the heavy load adjustment device, and the overhaul is easy. It is possible to provide a single rotating disk, two-element type watthour meter.

[Brief explanation of the drawing]

Figure 1 shows one of the conventional single-disc, two-element power meters.
A top view showing the arrangement of the driving element, braking magnet, etc., and Figs. 2 to 4 show an embodiment of the watt-hour meter according to the present invention, and Fig. 2 shows the arrangement of the driving element, braking magnet, etc. top view,
FIG. 3 is a side view showing the main parts of the electricity meter of the present invention-embodiment with the drive element omitted, and FIG. 4 is a perspective view showing the braking magnet and heavy load adjustment device of FIG. 3. . 3... Rotating disk, 4... Drive element, 5
a, 5b...braking magnet, 6...main frame,
7...Heavy load adjustment iron plate, 8...Heavy load adjustment screw, 9...Lower bearing, 10...
Upper bearing, 11...Measuring device.

Claims (1)

[Scope of utility model registration request] A main frame made of non-magnetic material, a pair of drive elements arranged oppositely on the left and right sides of this main frame, and a rotating disk inserted into the gap between the voltage and current cores of these drive elements, and the upper and lower sides of the drive elements. The bearings each include a rotor attached to the main frame and a metering device attached to the front part of the main frame, and by interaction with a magnetic flux proportional to the applied power generated by the drive element. In a power meter that measures power consumption by integrating the number of revolutions of the rotating rotor, a pair of brakes are inserted at the rear of the main frame so as to sandwich the rotating disk of the rotor, and apply braking torque to the rotor. a magnet, a heavy load adjustment iron plate slidably in contact with a non-magnetic material surface covering the surface opposite to the magnet disk located above the rotating disk of the brake magnet, and one end of the heavy load adjustment iron plate. A watt-hour meter comprising: a heavy load adjustment screw whose screw portion is rotatably engaged in the vicinity and is screwed into the front portion of the main frame, and whose tip is exposed on the front surface of the main frame.