SU67088A1 - Electrostatic Voltmeter - Google Patents

Description

Electrostatic type measuring instruments are already known, based on the mutual attraction or repulsion of two isolated electrodes, stationary and mobile, to which the measured potential difference is applied. In particular, such devices are known in which the movable electrode is made in the form of a whole rectilinear plate moving relative to a fixed electrode, having the form of a plate, the configuration of which is chosen depending on the desired shape of the scale of the device.

A feature of the device proposed in accordance with the invention, based on the above principle, is that the movable part of the device, at the same time with the arrow of the device, is made in the form of a loop of thin wire that encloses an arcuate curved fixed plate, the second electrode of the device, and when it rotates along this plate. Such a device of a mobile system is designed to reduce the moment of inertia and

ensuring sufficient rigidity of the moving electrode - the instrument arrows.

In addition, in order to be able to adjust the sensitivity of the instrument, at any part of its tongues, fixed tendrils made of inelastic wire are used, which are electrically connected to moving or fixed plates.

FIG. 1 of the drawing shows a general view of the proposed device, and FIG. 2 - constructive implementation of its mobile system.

The main part of the device is a movable loop-lining / (Fig. I), simultaneously serving as an arrow-pointer, and a fixed lining 6, which is a plate, the profile of which is calculated and experimentally adjusted so that the scale of the device is as uniform as possible.

The loop / and plate 6 are spatially arranged so that when the loop is rotated (clockwise), the fixed plate 6 is inside the loop /.

The movable loop 1 is soldered at its ends to a thin elastic metal thread 4 with a diameter of about 0.02 mm; the material of the yarn is platinum-iridium, nichrome, etc. Instead of a yarn, you can also use a flat elastic band. The ends of the thread or ribbon 4 are secured to the thin springs 7–7 (Fig. 2).

When the loop is rotated / the thread 4 is twisted, it creates an opposing moment that balances the moment that occurs during the electrostatic interaction of the loop / and the plate 6.

The base of the device is a plate 12,

The design of the moving system is shown separately in FIG. 2. The ends a and b of the loop 1 are fastened to the thread 4, and the ends of the same thread 4 are fixed on elastic springs 7-7. In addition to the ends of the loop are attached | Rod 8, which serves to increase the rigidity of the moving system, and the rod 9, equipped with a weight 13 to balance the loop 1 on the suspension 7-7.

In addition to these basic elements, in the design described here, there are auxiliary devices designed to adjust the sensitivity of the instrument in different parts of the scale.

To increase the sensitivity of the device at the beginning of the scale is fixed wire loop 2, electrically connected to the movable loop 1; The increase in sensitivity here is due to electrostatic repulsion of like-electrified loops 1 to 2.

The regulation of the P1kale sensitivity is achieved by using inelastic wire antennae 10 (Fig. 1), electrically attached to the fixed plate 6 and below the level of the moving system. This also refers to the short mustache 11, which is electrically connected to the mobile loop-arrow 1. By giving the antennae of various configurations, the sensitivity of the sensitivity of the voltmeter can be adjusted anywhere on its scale. Physically, this is due to the fact that when the antennae are bent, the electric field created by them moves and deforms; at the same time, the resulting field of the fixed plate and antennae is deformed, and since the uniformity of distribution of scale divisions depends on the shape of this resultant field, the dependence of the instrument sensitivity on certain areas of the scales on the wire antennae configuration becomes clear.

In the device there are corrector and arresting device, not listed on the black mark: the same, which can be performed on any of a number of known structures.

Subject invention

Claims (2)

1. Electrostatic voltmeter with a rotary arrow forming a movable plate of a capacitor, characterized in that in order to reduce the mass and moment of inertia of the arrow and ensure its sufficient rigidity, it is made in the form of a loop of thin wire covering an arcuately bent stationary plate of a capacitor and turning moving along this plate. 2. The form of the voltmeter according to claim 1, characterized in that, in order to adjust the sensitivity of the voltmeter, antennae made of inelastic wire connected electrically to the stationary ish1 with a movable plastip are used on any part of the scale.