CN1004841B - Twisting type direct-acting AC magnetic system - Google Patents

Abstract

A kneading type magnetic system for direct acting AC contactors and other electrical appliances with direct acting magnetic systems. The main feature of this design is that the iron core and armature pole surface are designed from the traditional horizontal snap-fit type to the one-way inclined-plane rubbing type with a horizontal angle between 20° and 40°. Since the upper and lower pole pieces are interlaced in one direction, the relative distance between the upper and lower pole surfaces is effectively shortened and the area of the pole surfaces is increased. The magnetic system of this design is compared with the conventional magnetic system. It has the advantages of doubling the initial suction, saving electric energy, reducing temperature rise, reducing vibration, reducing noise, prolonging life, reducing the amount of enameled wire and silicon steel sheet, reliable operation, and convenient use and maintenance. Its power saving is around 40%.

Description

Rubbing type direct-acting alternating-current magnetic system

The invention belongs to the field of magnetic systems with armatures. The inventors of the present invention proposed a rubbing type ac magnetic system in place of the clapping type magnetic system of the rotary contactor in the patent of "rubbing type ac magnetic system" filed in 1985, 12, 19 and application number 85205545. The basic principle of the present design differs from the above in that the resulting transverse component perpendicular to the main magnetic flux is opposite to the former, and its effect is also different. The former is installed and operated with the transverse component force downward, the moment formed by the armature part height as the arm is directly used for closing, while the transverse component force of the technology is upward for balancing the armature gravity. The above technique is used for rotary electric appliances, and the present technique is used for direct-acting electric appliances. The rotation and the direct motion are two kinds of electrical elements adopted at home and abroad at the same time, so that a user can select the electrical elements according to the specific requirements of controlled equipment. In some western countries, only direct-acting electric appliances are used, and most of China adopts direct-acting type, so that the use amount of the direct-acting magnetic system is larger than that of the rotary type.

The beating magnetic system which is commonly used at present is a cylindrical pole shoe and is directly beating, and the structure has the defects of large vibration caused by frontal collision, short service life caused by large vibration, impact on a power grid caused by large required starting current, small initial suction force caused by insufficient electromagnetic force, large volume, high material consumption, high manufacturing cost, large noise caused by unidirectional suction, large energy consumption, high temperature rise and the like. The prior art has forms of V shape, B shape and the like besides the cylindrical pole shoe. Although the pole shoes are shaped like a rubbing, the horizontal component forces generated by the pole shoes are counteracted by the equal directions, and the horizontal component forces only can generate damping action and are not helpful for balancing the gravity of the armature.

In the aspect of electricity saving, a method of adding an electricity saving device on a magnetic system is adopted at home and abroad at present, the electricity saving amount of a single unit is quite considerable, and silent operation can be realized. However, there is a large vibration. Unreliable operation, low operating frequency, short service life, multiple increase of equipment cost, multiple increase of closing or releasing time, volume increase and the like. Is not a method for fundamentally and comprehensively improving the technical and economic indexes of the magnetic system.

Aiming at the defects of the existing magnetic system, the invention provides a technology for changing the mechanical action of directly beating the upper pole face and the lower pole face into the relative rolling of the upper wedge shape and the lower wedge shape, namely, before the armature starts to act, the relative distance between the upper pole face and the lower pole face is shortened, the pole face area is increased, and the leakage magnetic flux is reduced. In the action process, besides the action of the vertical component force, the horizontal component force perpendicular to the main magnetic flux can play a role in balancing the gravity of the armature and can lead the upper pole face and the lower pole face to generate relative magnetic force to be rubbed. Thus, the defects of the prior art are radically overcome at one time, and the technical and economic indexes are fully broken through.

The invention adopts the technology that the clapping is changed into the rubbing, and electromagnetic force is fully utilized, thereby saving electric energy and reducing vibration. The armature is closed in a state close to weightlessness, so that the working reliability is improved, the mechanical abrasion of the guide rail is reduced, and the service life is prolonged. The consumption of enameled wires and silicon steel sheets is reduced, and the manufacturing cost is reduced. The temperature rise is reduced, the starting current is reduced, the initial attraction force is increased in a multiplied mode, the armature is held by mutually perpendicular bidirectional forces, and noise is reduced.

The design principle of the invention is described in detail below with reference to fig. 1:

In the figures, (1) and (1') represent pole faces of the core. (2) and (2') represent armature pole faces. The horizontal dashed lines in the figure represent the clapping core and armature pole faces, and the shaded portions included represent their clapping magnetic force application areas. The area enclosed by the left and right vertical dashed lines and the pole faces (1) (2) and (1 ') (2') represents the magnetic force application region of the present technique. As can be seen from FIG. 1, compared with the clapping type magnetic force acting area, if the intersecting angle of the two pole faces is 30 degrees, under the condition of unchanged working stroke and magnetic pole thickness, the upper and lower pole distance air gap can be shortened by 13.4%, the corresponding pole face area is increased by 15.5%, and the magnetic force acting area is the main principle that the initial suction force of the technology is increased by times and electricity can be saved greatly. Because the air gap is inversely proportional to the square of the electromagnetic attraction force, the increase of the pole face can greatly reduce the leakage magnetic flux to strengthen the working magnetic flux.

In addition, since the pole faces (1), (1 '), (2') are all unidirectional slopes, the magnetic force lines have the characteristic of passing through the air gap vertically, and the magnetic force can be decomposed into a vertical component force Fy and a horizontal component force Fx. When the coil on the iron core is electrified, the upper and lower pairs of pole faces are rubbed by the generated magnetic force. Fx is directed upward during installation operation to balance the weight of the armature. In order to eliminate the additional split magnetic ring, the electric energy loss is reduced. The center line of the two pairs of corresponding rivets (3), (4) and (3 '), (4') abutting the pole face should be substantially perpendicular to the pole face after the upper and lower pole faces are closed. The angle between the line and the normal of the pole face should be 0-5 DEG, and is optimally 3-7 deg.

The preferred embodiment of the present invention is described in detail below with reference to fig. 2:

In the figure (6) is a magnetic system bottom plate, and a static iron core (1), a guide rail (3) and a reaction (buffer) spring (4) are arranged on the bottom plate. The exciting coil (5) is sleeved on the pole shoe of the static iron core. The armature (2) is arranged on the guide rail (3) and can do parallel reciprocating movement. For the purpose of balancing the armature force, two coils (5) are usually connected in series and then sleeved on two pole shoes of the static iron core, and for the sake of simplifying the drawing, only one coil (5) is shown in fig. 2. In addition, the upper and lower iron cores can be designed into E shape, the coil is sleeved on two pole shoes of the symmetrical edge static iron core, and the pole shoes and the pole faces of the corresponding armature pole shoe are in a rubbing structure. The central main pole is cylindrical, and a demagnetizing air gap is reserved between the upper and lower middle poles and is not contacted with each other. The core shown in fig. 2 has an n-shaped structure.

In the two rubbing type direct-acting magnetic systems, the pole faces (except the E-shaped middle pole) of the static iron core and the armature are all unidirectional inclined planes. The included angle between the unidirectional inclined plane and the vertical line of the sliding direction of the guide rail (3) is 20-40 degrees, and is optimally 30 degrees. The iron core and the armature are both formed by clamping silicon steel sheets in two steel plates and riveting the silicon steel sheets into a whole by rivets. In order to avoid forming two additional magnetic split rings, reduce energy loss and reduce temperature rise, after the upper iron core and the lower iron core are closed, the central connecting line of the upper pair of corresponding rivets and the lower pair of corresponding rivets, which are close to the pole faces, is basically vertical to the pole faces. The angle between the connecting line and the normal of the pole face is 0-15 deg. And most preferably 3 to 7 degrees.

When the magnetic system works, the coil (5) is electrified, and at the moment, the magnetic force generated by the static iron core (1) attracts the armature (2) to enable the upper pole face and the lower pole face to be closed. Meanwhile, the reaction (buffer) spring (4) is compressed, and as the pole face is a unidirectional inclined plane, a component force Fx perpendicular to main magnetic flux is generated, so that the gravity of the armature (2) is balanced, the armature is in a state of approaching weightlessness and is in straddling with the static iron core (1), and after a power supply is cut off, the reaction spring (4) enables the armature to reset, and the upper pole face and the lower pole face are separated. The magnetic system is used for reciprocally completing the action process.

Compared with the traditional clapping type magnetic system, the rubbing type direct-acting alternating-current magnetic system provided by the design has the advantage that the relative gap between the upper pole face and the lower pole face is obviously reduced. The corresponding pole face is greatly increased, the leakage magnetic flux is correspondingly reduced, and the initial suction force is multiplied. The volume of the magnetic system can be reduced and the forces with mutually perpendicular directions act simultaneously in the closing, when used under the same conditions. The device has the advantages of obvious electricity saving, small vibration, low noise, low temperature rise, long service life, high operating frequency, reliable action, copper and steel saving, low manufacturing cost, convenient use and maintenance and the like. The comprehensive improvement of the technical and economic indexes is impossible to achieve by adopting a clapping structure, and the popularization and application of the technology bring revolutionary changes to the design of an electromagnetic system.

The effect of the technique provided by the invention compared with the conventional clapping type in terms of energy consumption is shown in fig. 3. The ordinate in fig. 3 indicates the magnetic force, the abscissa indicates the working air gap, and the broken line (1) indicates the inherent reaction characteristic of an electric product. The curved line (2) represents the suction characteristic of the original beat-up using the original ampere-turns. The dash-dot line (4) shows the suction characteristic curve of the rubbing type coil using the ampere-turns of the original beating type coil, and the dotted curve (3) shows the suction characteristic curve of the rubbing type structure provided by the design, which is 40% less than the ampere-turns of the original coil. As can be seen from FIG. 3, the rubbing type energy saving is shown as a ox horn shaped shadow area in the figure. Greatly reduces the energy consumption, also obtains the initial suction which is one time larger, and reduces the final suction by one sixth. If the same energy consumption is used, the initial suction force can be increased by about two times. The entire characteristic curve is shifted up. An increase in suction force is initiated. The closing speed can be effectively increased and the action reliability can be improved. The reduction of the final suction force saves electric energy and reduces vibration. Because the suction characteristic and the reaction characteristic are reasonably matched, the electric energy can be saved by about 40 percent.

Description of the drawings:

FIG. 1 is a schematic diagram of the principle of operation of a magnetic system

FIG. 2 is a schematic diagram of a magnetic system configuration

FIG. 3 attraction characteristic of magnetic System

Claims (3)

1. A rubbing-type AC magnetic system for DC contactor and other electric appliances with DC magnetic system features that its iron core and armature have wedge-shaped inclined surfaces for rubbing them together.

The invention is characterized in that the pole faces of the iron core and the armature are unidirectional inclined surfaces, the horizontal angle of the unidirectional inclined surfaces is 20-40 degrees, and under the operating condition, the component force (Fx) perpendicular to the main magnetic flux, which is generated between the two pole faces of the magnetic system, plays a role of balancing the gravity of the armature (as shown in figure 2), so that the armature is in rolling engagement with the static iron core in a state close to weightlessness.

2. A magnetic system as claimed in claim 1, wherein the upper and lower pole faces of the core and armature are parallel to each other, and the optimum unidirectional bevel is at an angle of 30 ° to the horizontal.

3. A magnetic system as claimed in claim 1, wherein the centre line of the first corresponding rivet abutting the pole face after closing of the upper and lower pole pieces is substantially perpendicular to the pole face, the line being at an angle of between 0 and 15 ° to the normal to the pole face, preferably 3 to 7 °.

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