Threaded electrical insulator and method for cleaning it

Description

[0001] The present invention relates to an electrical insulator with a thread-shaped surface and a threaded brush for cleaning the insulator surface. The insulator with a thread and its cleaning brush can be used e.g. in dusty places, in particular in devices for dust removal from gases, i.e. electrostatic precipitators.

[0002] The cleaning of the threaded insulator consists of turning the insulator around its axis with the rotation of the brush prevented, as a result the brush moves along the threaded insulator. The same effect can be achieved by turning the brush around the immobilized insulator. The brush moving along the insulator scrapes off the dust from its surface. Reversing the direction of rotation (of insulator or brush) returns the brush to its original position.

[0003] Patent EP0278606A2 discloses an electrical insulator for use in a humid and polluted environment. It was formed into a mandrel from which the protrusions extend symmetrically at an angle of 30 - 90 degrees to the mandrel. This construction allows condensed water to run down the insulator, which causes the surface is cleaned.

[0004] Patent US5421863A discloses a device with an electrically insulating disk for use in an electrostatic precipitator. The insulator is attached to a high voltage rod. The electrostatic precipitator channel is equipped with a device for supplying compressed ventilation air or other gas as an insulator cleaning agent.

[0005] Patent US3257501A discloses a method of obtaining an electrical insulator and its construction. The insulator has the shape of a truncated cone with a spiral cavity, whose task is to drain water from the surface of the insulator.

[0006] Patent US2897386A discloses a self-cleaning insulator used, e.g. in electric machines. The insulator is made of a high voltage insulating element which has an exposed surface subjected to current discharges or cross arcs for cleaning the dirty surface of the insulator.

[0007] Patent US2155848A discloses an electrical insulator, particularly well-suited for use where it is exposed to moisture, such as rain or fog. The water settling on its surface creates a continuous stream with a substantially homogeneous resistance to obtain a uniform voltage drop on the insulator.

[0008] Patent US7387167B2 discloses an electrically insulating drilling tool device for insulating the first conductive element from the second conductive tool element.

[0009] Patent application CN 105234109 A discloses a self-rotating type insulator cleaning device and relates to the technical field of maintenance of electric power equipment for a transformer substation. This cleaning device is for typical, well known insulators working in atmospheric ambient air. It cannot be used inside e.g. electrostatic precipitators operating with high temperature and highly contaminated gases.

[0010] Patent PL 232565 B1 discloses a device for electrostatic precipitation of gases. Design of the device makes that it is enough to rotate the discharge electrode, to ensure that all critical components for efficient dedusting are cleaned.

[0011] Patent GB 244981 discloses an insulator for wireless aerials and other outdoor purposes which is provided with a device for automatically removing deposit of dust. The insulator is in the form of a rod on which is loosely mounted a rotator comprising a hub, preferably of ebonite and vanes.

[0012] Patent application WO 2018 / 090990 discloses an electric field device with an automatic cleaning function, comprising a bracket, at least one hollow cylindrical collecting pole, and a corona rod placed on the central axis of the hollow cylindrical collecting pole. The corona rod is provided with an external thread that matches with the internal thread on the rotor, and a dust sweeper that is in contact with the inner wall of the hollow cylindrical collector pole is provided on the periphery of the rotor.

[0013] The purpose of the present invention is to provide an electrical insulator with a thread and a brush to separate elements with a significant difference in electrical potential, even in a highly polluted environment. This problem has been solved to a significant extent in the present invention.

[0014] The present invention relates to an electrical insulator according to independent claim 1 and a method of cleaning such insulator according to claim 7. Further embodiments are claimed in the dependent claims.

[0015] An advantage of the invention is its construction, which allows to rotate one of the elements, i.e. the insulator or the brush (while blocking the rotation of the other element) for simple removal of collected particles from the surface of the insulator. This makes it easy to keep the insulator surface clean, which is a key factor in ensuring that the electrical insulator works properly.

[0016] The invention is set out in the appended set of claims 1-8.Description of the figures:

[0017] Fig.1 - presents cross-section of an electrical insulator with a brush and other elements used to clean the insulator Fig.2 - presents cross-section of a variant of electrical insulator with a hole through the center, along its axis Fig.3 - presents cross-section of a variant of brush with a convex scraper with teeth Fig.4 - presents cross-section of a variant of brush with an additional wire brush. Description of reference numerals:

[0018] 1 -electrical insulator 2 -surface in the form of a thread 3 -brush 4 -motor 5 -guide 6 -supporting element 7 -motor controller 8 -metal rod 9 -connector 10 -sleeve 11 -non-rotatable attachment of a high-voltage element 12 -convex scraper on the brush 13 -first convex scraper tooth 14 -wire brush The present invention is illustrated by the following example construction which is not a limitation of it.

[0019] The electrical insulator (1) of cylindrical shape has a thread-shaped surface (2), is attached to the motor (4) and has the guide mounted (5) brush (3), which allows removing the dust deposited on the surface of the insulator (1). Cleaning of such an insulator (1) is carried out in such a way that it is driven by a motor (4) and can rotate around its axis, but cannot move along this axis, while the brush (3) attached with a guide (5) cannot rotate, but it can move along the axis of the insulator (1). Therefore, rotating the insulator (1) causes the brush (3) to move and remove the dust deposited on the insulator. The work of the motor (4) rotating the insulator is operated by the controller (7), which provides a voltage to the motor and controls the direction and number of its rotations.

[0020] According to the invention the electrical insulator (1) for separating elements with a significant difference in electrical potential, in particular for operation in a highly polluted environment (e.g. in dust removal devices), is made of a dielectric material, e.g. ceramics. The insulator surface is in the form of a thread (2) and it can be metric, trapezoidal or other thread. The brush (3) made of dielectric material fits to this thread. The insulator is attached to the motor (4), which can rotate it in both directions, but it is impossible to move the insulator along the axis of rotation. The brush (3) is attached with a guide (5) that does not allow the brush to rotate, but allows the brush to move along the insulator axis (1). All these elements are attached to the supporting element (6), which can be the housing of the dust removal device. The supporting element (6) can be made of e.g. sheet metal and can be grounded. The element with high electrical potential (e.g. discharge electrode in the ESP, high voltage wire) is mounted on the bottom of the insulator with a rotary joint, so that the rotation of the insulator does not rotate the element (Fig. 1).

[0021] In one of the variants, the insulator (1) can have a hole through the center (along its axis) and a metal rod (8) with high voltage applied passes through this hole. The rod (8) is mounted in this hole and it is used to rotate the insulator around its axis. The motor rotation (4) is transmitted to the rod (8) by an additional connector (9) made of dielectric material, causing rotation in a sleeve (10) which is made of dielectric material (Fig. 2).

[0022] According to the invention, the brush (3) has at least one convex scraper (12) fitting to the insulator thread, resulting in scraping the dust deposited on the insulator thread. It is beneficial when the first convex scraper tooth (13) is full, i.e. fills the entire thread cavity on the insulator (Fig. 3).

[0023] In one of the variants, the brush (3) fitting to the insulator thread can be equipped with an additional wire brush (14) with wire ends surrounding the insulator thread, which scrape the dust deposited on the insulator thread (Fig. 4).

[0024] In another variant of the insulator (1) and the brush (3), the cleaning of the insulator can also be done by rotating the brush while preventing the insulator from rotating, causing the same effect, i.e. the brush moving along the insulator.

Claims

1. An electrical insulator (1) mounted to a supporting element (6), with a brush (3) and a motor (4) attached to the electrical insulator (1), where the brush (3) is mounted with a guide (5) attached to the supporting element, wherein the motor (4) is configured to rotate the insulator (1) around its axis, characterized in that the insulator (1) is of cylindrical shape and has a thread-shaped surface (2), and the brush (3) has at least one convex scraper (12) fitting to the insulator thread (2).

2. The electrical insulator according to claim 1, characterized in that a first convex scraper tooth (13) of the brush (3) is full and fills the entire thread cavity on the insulator (1).

3. The electrical insulator according to claim 1, characterized in that the brush (3) fitting to the thread (2) of the insulator (1) is equipped with an additional wire brush (14) with wire ends surrounding the insulator thread (1).

4. The electrical insulator according to claim 1, characterized in that the insulator (1) is made of dielectric material.

5. The electrical insulator according to claim 1, characterized in that the thread (2) is metric or trapezoidal.

6. The electrical insulator according to claim 1, characterized in that the brush (3) is made of dielectric material.

7. A method of cleaning the insulator, as defined in claim 1, which is driven by a motor, whose work is operated by a controller that provides a voltage and controls the direction and number of the motor rotations, the insulator rotates around its axis and this rotation of the insulator causes a brush which is attached to a guide (5) and to a supporting element (6) to move along the axis of the insulator characterized in that a thread-shaped surface (2) of the insulator (1) is scraped by a convex scraper (12) of the brush (3) causing removal of particles deposited on the insulator (1).

8. The method according to claim 8, characterized in that the insulator (1) can have a hole through the center along its axis, and a metal rod (8) with high voltage applied passes through this hole and is mounted in this hole and used to rotate the insulator (1) around its axis, where the motor (4) rotation is transmitted to the rod (8) by an additional connector (9) made of dielectric material which rotates in a sleeve (10) made of dielectric material.