JPH0121465Y2 - - Google Patents

Description

[Detailed description of the invention] The invention includes a cradle or hook;
a spring loaded mechanism adapted to be latched in a loaded or reset position by a latching structure, in which the hook engages one pair of the latching structures; The invention relates to a circuit breaker tripping device which exhibits a hook surface cooperating with one of the rollers and the other roller cooperating with a fixed support area. A spline is inserted between the two rollers, and by sliding the spline, the roller is pushed or rolled in the position where the hook is released.

This type of trip device utilizes a latch member or roller that is moved with low friction by pushing. These rollers can provide large reaction forces without requiring significant force to unlatch, making them particularly suitable for large rated circuit breakers requiring strong springs. A spline inserted between the two rollers transmits the drive motion to the rollers without creating any friction. In known devices of this type mentioned above, the splines are reliably controlled, for example by electromagnets, and the entire structure is arranged in such a way that the reaction force of the rollers is applied perpendicularly to the splines, in order to reduce the control forces as much as possible. Ru. In theory, therefore, the sliding force is independent of the reaction force, thereby avoiding unlatching at an inappropriate time under the action of those forces. In other devices, rollers contact the inclined surface and apply a moving force to the spline in the direction of release, so that the spline automatically unlatches as soon as it is released. These known devices often fail due to the rollers sticking to the surface.

The aim of the invention is to overcome this drawback by providing a self-releasing circuit breaker which releases its adhesion to the surface with a small release movement. A trip lever acts laterally on the spline. The small movement in the support area of the roller caused by this lateral movement of the spline weakens the adhesion force and initiates sliding of the spline.

In order to avoid tripping at inappropriate times, especially to avoid tripping due to impact, in this invention the spline inserted between the rollers is Biased into latched position. This self-latching action requires a greater unlatching force. The unlatching force can easily be kept within acceptable limits.

The roller, which may consist of a ball or any other rotating body, is advantageously held in a cage biased into a latched position by a spring. When the hook is released, the roller automatically returns immediately to the latched position since the spline is also surrounded by a tension spring. When the circuit breaker is reset, the hook temporarily pushes the roller back and engages, and during this switching action the unstressed roller slides over the splines and springs.

Hereinafter, the present invention will be described in detail with reference to the drawings.

A cradle or hook 10 of the circuit breaker mechanism of the present invention (not shown) is shown in cooperation with a roller latch structure 12. The circuit breaker has a molded casing provided with a handle for manual operation and can be of the type that automatically trips in the event of a fault in the electrical circuit. Such circuit breakers are well known and are disclosed, for example, in US Pat. No. 3,155,802. Such a circuit breaker has an energy storage spring (not shown) for opening the contacts when the hook 10 is released under a tripping action.

When the circuit breaker is in the closed position, the nose-shaped end 14 of the hook 10 is connected to a pair of rollers 1 held overlappingly in a retaining cage 20.
This corresponds to the lower roller 16 of the rollers 6 and 18. The upper roller 18 is attached to a fixed support member 24
A support area of is also supported on 22. roller 1
6, 18 and the cage 20 are supported by the support member 24 in a confined manner parallel to the support region 22 within the support member 24. roller 1
The end of spline 26 is inserted between 6 and 18. This spline 26 extends generally parallel to the support area 22 and across the cage 20. In the latched position, the other end 28 of the spline 26 engages the stop plate 30 of the support member 24 to prevent the spline 26 from sliding to the right in the drawing. The trip lever 32, which is rotatably mounted on the shaft 34, hits the end 28 of the spline 26 when the circuit breaker is tripped;
The end 28 is raised above the edge of the stop plate 30 to release the spline 26 from the latched condition. This spline 26 can then slide freely.

The force with which the hook 10 is pulled is the roller 1
6, splines 26, and rollers 18 to the fixed support member 24. Referring now to FIG. 5, the support area 22 is slightly sloped to form a corner at a small angle with the end 14 of the hook 10;
It can be seen that the force exerted by the rollers 16, 18 drives the rollers 16, 18 from their corners to the right in the diagram. When the spline 26 is latched, the rollers 16,18 cannot slide due to the large frictional forces between the spline 26 and the support areas 22,36 and the rollers 16,18. spline 2
6 is unlatched, rollers 16,1
8 is rotated, so that the spline 26 is moved in the direction of the arrow shown to the right in the figure. Rolling friction is very small even in the presence of large pulling forces. The roller 1 is used to automatically release the latch of the hook 10 using the latch release force obtained from the latch force.
By rolling the splines 6 and 18, the spline 26
is sufficient to move the rollers 16,1
It is easy to select the angles of the support areas 22, 36 such that they are insufficient to be moved by a sliding motion of 8. After the rollers 16, 18 have moved a predetermined distance to the right in the figure, the end 14 of the hook 10 slides and the released hook 10 rotates toward the tripped position. Of course, a cut 38 is provided in the cage 20 and support 24 to allow the hook 10 to pass through (FIG. 4).

Spline 26, which is clamped between rollers 16 and 18, is biased toward a position perpendicular to the line O ₁ , O ₂ midway between rollers 16 and 18 due to its clamping force. That position corresponds to the position where spline 26 is latched. In FIG. 5, spline 26 is shown attempting to rotate clockwise relative to trip lever 32 and stop plate 30. This latched position is a stable position that avoids being tripped at inappropriate times.

When tripping, the tripping lever 32 is connected to the spline 2
6 counterclockwise in the figure to raise the end 28 of the trip lever 32 above the edge of the stop plate 30 and release the spline 26 from the latched condition. During this rotational movement of the spline 26, the contact point B ₁ between the rollers 16, 18 and the spline 26,
B ₂ can be changed. Therefore, the adhesion force is canceled and the rollers 16, 18 roll to the right in the figure, thereby starting to self-release the latched state. Their displacement of contact points B ₁ , B ₂ is very small but sufficient to eliminate the risk of hook sticking.
The trip lever 32 must overcome the sliding friction forces between the stop plate 30 and the end 28 and the centering forces exerted by the rollers 16, 18, which are easily controllable and ultimately Can be made smaller.

A tension spring 40 secured to the shaft 34 and the spline 26 pulls the spline 26 to the latched position, and a spring 42 inserted between the stop 44 supported by the spline 26 and the cage 20 pulls the cage 20. bias toward the hook position.

Next, the operation of this mechanism will be explained.

In the latched position shown in FIG.
6, 18 and is absorbed by the fixed support member 24. Even if the rollers 16, 18 are pushed, the splines 26 are in contact with the stop plate 30, so that the rollers 16, 18 are prevented from moving. Because the surface 36 of the end 14 of the hook 10 is slightly sloped, a component of force is generated that tends to cause the spline 26 to slide toward an unlatched position. This component force is absorbed by the stop plate 30. When a failure occurs, the trip lever 32
rotates in the triangular direction of the trip lever 32 against the end 28 of the spline 26. In the first stage, spline 26 rotates and spline 26 rotates.
When the end 28 of the spline 26 slips from the stop plate 30, the spline 26 immediately slides in a second stage towards the unlatched position under the action of said force component. During this second stage, roller 1
6 and 18 roll while moving toward the spline 26 to release the hook 10 (FIG. 3). When the hook 10 is released, the springs 40, 42 immediately pull the spline and rollers 16, 18 back into the hook position (FIG. 1).

Simultaneously with this reset action, the hook rotates in the opposite direction, and before it returns to and remains in the position shown in FIG. It is returned to the position shown in the figure.

The mechanism of this invention has a simple structure, high reliability,
Enables control of large hook forces, which are important in large rated circuit breakers.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the roller latch structure of the present invention, and FIGS. 2 and 3 show the latch structure of FIG. 1 on its way to the unlatched position and in the unlatched position, respectively. Figure 4 is a sectional view taken along the - line in Figure 1;
FIG. 5 is a partially enlarged view of FIG. 1. 10... Cradle (hook), 12... Roller latch structure, 16, 18... Roller,
20...cage, 26...spline, 30...
Stop plate, 32...Trip lever, 40, 42
...Spring.

Claims (1)

[Claims for Utility Model Registration] (1) A circuit breaker tripping device having a spring-loaded operating mechanism provided with a latchable cradle and a latch structure for latching the cradle in the loaded position. the latching structure comprises a pair of cooperating rollers and angled oppositely to bias the rollers to roll the pair of rollers in an unlatched position freeing the rollers; , a fixed drive surface that drives one of the pair of rollers, and a fixed drive surface that is inserted between the pair of rollers and extends between the latched position and the unlatched position to prevent the roller from rolling in the latched position. a latched spline capable of pivoting movement, sliding freely in an unlatched position to allow the roller to roll, and prevented from sliding in a latched position to prevent rolling of the roller; a locking stop whose edge engages an edge of the spline in the latched position; and a trip lever which, when tripped, acts positively on the spline to pivot the spline to the unlatched position; The cradle has a drive surface that contacts the other roller of the pair of rollers in the latched position, and the edge of the spline, pivoted into the unlatched position by the trip lever, is released from the fixed stop. the spline is allowed to slide, thereby causing the latching structure to unlatched on its own, and the pivoting movement of the spline causing a small movement that weakens the adhesion of the roller to the drive surface. Features a circuit breaker tripping device. (2) the fixed drive surface and the drive surface of said cradle form an acute angle, said spline being latched along the bisector of said angle such that rollers bias the spline toward the latched position; The tripping device according to claim 1, characterized in that the tripping device extends toward the position. (3) further comprising a cage holding the pair of rollers, the cage holding the rollers passing through the spline inserted between the rollers and the spring for biasing the cage holding the rollers and the spline to a latched position; The tripping device according to claim 2, wherein the cage is provided with a slot.