EA014194B1 - Device for controlling an electric protection device and electric protection device including same - Google Patents

Abstract

The invention relates to a device for controlling of an electrical protection device placed in an insulating housing (1) containing a pair of fixed (5) and movable (4) contacts, the aforementioned movable contact (4) being able to be actuated either manually via a joystick (6) or automatically, comprising - a transmission rod (10) coupled with the joystick (6), a support mechanism (3) of the movable contact (4), comprising a rotatably mounted plate on a pivot (31) and having a mechanical breakable connection with the transmission rod (10) and a release lever (16) controlled by a release mechanism to cause in the event of defect the break of the mechanical connection, involving the automatic release of the mechanism independently of the joystick (6) and the separation of the contacts (4, 5), wherein the mechanical breakable connection being formed by a retained notch in the release lever (16) cooperating with a locking hook (19) mounted rotatably on plate pin (20), wherein the break of the mechanical connection corresponds to the unlocking of the release. The device is characterized in that the transmission rod (10), in locking position of the hooking, presses on plate (15) and on the hook of locking (19), the relative positions of the two bearing surfaces respectively to plate (15) and the hook (19) as well as the ratio of the two lever arms allowing the reduction of the effort of the rod on the release lever, being selected so that the effort applied to the hook is lower than the effort applied to the plate.

Description

The present invention relates to a working device for an electrical protective device housed in an insulating casing containing a pair of fixed and movable contacts, wherein said movable contact is designed to be switched on either manually using a handle or automatically containing a transmission rod connected to the handle, a support mechanism a movable contact comprising a support plate mounted rotatably on an axis and having a breakable mechanical link to a gear unit with a lever, and the release lever, controlled by the release mechanism, for opening the mechanical link in the event of a malfunction, which leads to automatic release of the mechanism regardless of the handle and opening the contacts, while the opening mechanical link is formed by means of a holding cut-out in the release lever, working in conjunction with a latch mounted rotatably on the pin of the plate.

From the patent of the Republic of Kazakhstan 2589627, a transmission rod is known to work in cooperation with the plate. In this device, the force of the mechanism is perceived by 2/3 of the plate and by 1/3 of the trip rod. However, there is no mechanical action that reduces the acting forces.

From the patent of RK 2616583 the working mechanism of a miniature circuit breaker is also known, containing the above characteristics. In this patent, an assembly comprising a transmission rod, a latch and a release lever forms a lowering transmission stage, which provides a reduction in the releasing force.

In this mechanism, the force of the rod causes a latching torque. This geometry does not optimize the further reduction of the latching force due to the size of the mechanism relative to the standard size of the modular pole blocks of the circuit breaker. Consequently, the size of the magnetic and thermal protective devices cannot be reduced further. This limits the performance of circuit breakers due to the temperature increase caused by these devices.

The present invention solves these problems and provides a working device for an electric device, with which it is possible to improve the characteristics of this device.

To this end, the purpose of this invention is to provide a working device for an electrical protective device of the above type. This device is characterized in that the transfer rod in the latched latch position presses on the plate and on the latch, while the relative positions of the two supporting surfaces relative to the plate and the latch and the ratio of the two lever actions, allowing to reduce the rod force on the release lever, are selected so that the force applied to the latch, less force applied to the plate.

According to a particular feature, the relative positions of the two bearing surfaces and the ratio of the two lever actions are selected so that the force applied to the latch is about seven times less than the force applied to the plate.

According to another particular characteristic, the latch and the release lever are made with a reduced thickness to ensure that the screen for protection against contamination to be placed between the rod and the snap zone is placed between the latch and the release lever.

According to another feature, the latch is made of a cut metal plate or plastic.

According to another feature, the latch and the plate, both contain a hole designed to allow the plate to rotate when automatic disengagement occurs, while the rod is locked in the closed position of the contacts by the handle.

According to another feature, the plate also contains an opening designed to guide the rod to its original position, pressing against the plate when the handle returns to the open position of the contacts after automatic disengagement.

According to another characteristic, this device comprises a spring with two branches fixed on the lever, comprising a first branch intended to move the trip lever back to its initial position of readiness for latching after the disengagement has occurred, and a second branch intended to move the latch to a preferred position in which there is sufficient clearance between the latch and the lever to facilitate latching the latch on the specified lever after automatic disengagement.

Another objective of the present invention is to provide an electrical safety device comprising a working device having the above features individually or in combination.

Other advantages and features of the invention result from the following detailed description with reference to the accompanying drawings, which are given only as an example, and which depict:

FIG. 1 is a partially internal device of a circuit breaker with a working device according to a particular embodiment of the invention in the open position of the contacts and the handle in the form

- 1 014194 from above;

FIG. 2 - circuit breaker according to FIG. 1, while the device is in a position corresponding to the beginning of the contact closure;

FIG. 3 - circuit breaker according to FIG. 1 in the closed position of the contacts and the handle and with the screen of protection against pollution;

FIG. 4 - circuit breaker according to FIG. 3 with the working device in the closed position of the contacts and the handle on an enlarged scale;

FIG. 5 - partially working device in the disengaged position, while the handle is held in a closed position in a plan view;

FIG. 6 - working device according to FIG. 5, but with an additional image of the pollution protection screen;

FIG. 7 - circuit breaker according to FIG. 1, but with an additional image of the anti-pollution screen.

The drawings show a miniature electric circuit breaker with a molded insulating housing 1 containing a working device 2 according to the invention. This device contains a support mechanism 3 of the movable contact 4, while the specified movable contact operates in cooperation with the stationary contact 5.

A hole 7 is provided in the front panel 8 of the housing for passing the handle 6, which is mounted for limited rotation on the housing pin 11 between the closed position in which the contacts 4, 5 are closed and the open position corresponding to the opening of the contacts 4, 5. The handle 6 is provided with an internal base 9 connected to the transmission rod 10 to form a knee mechanism, the hinge 12 of which is eccentric relative to the fixed pin 11 of the handle 6.

The handle 6 is spring loaded counterclockwise to the open position of the contacts using a return spring (not shown). The fixed contact 5 is fixed on the housing of the electromagnetic release mechanism 13. The movable contact 4 is fixed on the support mechanism 3 of the movable contact 4, while the specified base 3 is pivotally mounted on the axis 14, while the rotary plate 13 is mounted for rotation around axis 31.

The release lever 16, actuated by the drummer of the electromagnetic release mechanism, and the bimetal strip of the thermal release mechanism (not shown) or an external auxiliary mechanism are mounted to rotate on a pin 17 mounted on the plate 15 with a predetermined offset relative to the above axis 14.

The disconnectable mechanical link is located between the transmission rod 10 and the drive plate 15 of the support mechanism 3 of the movable contact 4.

In the latched position, the link provides manual control of the mechanism through the handle 6. Moving the release lever 16 to the disengaged position due to the action of the release mechanisms causes the mechanical link to instantly open, which leads to automatic release of the mechanism independently of the handle 6. The release lever 16 is connected to the return spring 27, designed to automatically restore the mechanical link when the handle 6 is moved to the open position after the mechanism is released when equality.

The openable mechanical link includes a latch 19 that can be rotated on the pin 20 of the plate 15. Opposite to this pin, the nose 21 (see Fig. 4) of the latch 19 operates in the latching position of the link in cooperation with the retaining cutout 22 (see Fig. 4), located on the shoulder of the release lever 16. The transmission rod 10 is connected to the latch 19 and the plate 15 at the hinge point 23, which is able to move when the trip occurs, in two consecutive holes 24 and 26 of the plate 15.

The hinge point 23 is located between the hinge pin 20 (see FIG. 3) of the latch 19 on the plate and the nose 21 (see FIG. 4) of the latch. The link forms a reduction gear stage in the kinematic chain of the device, reducing the tripping force created by the magnetic thermal release mechanism.

The latch 19 also contains a kidney-shaped or U-shaped hole 25, which, together with the holes 24 and 26 of the plate, is designed to rotate the contact support plate 15 when disengaging, while the rod 10 is locked by the handle 6 itself, held in a closed position contacts.

The hole 26 provided in the plate 15 also provides directional movement of the rod when the handle returns to the open position of the contacts after disengagement. Two holes 24, 26 of the plate 15 extend relative to each other with the formation of a U-shaped.

A bias spring 27 with branches 28, 29 is installed around the pin 17 on the lever 16. One branch 28 is designed to return the trip lever 16 to its original position, while the other branch 29 springs the latch 19 to the preferred position, selected so as to create sufficient the gap between the lever 16 and the latch 19 to provide a snap.

A shield 30 (see FIGS. 3, 6 and 7) integrated into the release lever covers the snap zone

- 2 014194 release lever 16 with a latch 19. This screen is installed between the rod and the snap zone and protects the snap zone from the protrusions due to opening.

The following is a description of the operation of the device with reference to the drawings.

In FIG. 1, the working device is in the position in which the contacts are open, while the handle is in the open position.

When the handle 6 is actuated to close the contacts (see FIG. 2), it moves the rod 10, which then presses on the plate 15 and the latch 19 (see FIG. 2). The latch 19 latches onto the trip bar (or lever).

The rod 10, pressing on the plate 15 and on the latch 19, causes the plate to rotate around its pin 31 until the contacts 4, 5 close.

The rod continues to move until the dead center of the knee link mechanism formed by the handle and the rod. Then, the mechanism takes an equilibrium position with the contacts 4, 5 held in a closed position, as shown in FIG. 3 and 4.

To open the contacts 4, 5, the handle 6 is manually actuated until the dead center of the knee lever mechanism passes in the opposite direction. The mechanism then reaches the equilibrium position with open contacts when the handle reaches the end of its movement in the position shown in FIG. one.

When the contacts are closed and the release lever is actuated, the latch 19 opens, however, the handle 6 does not return directly to its open position.

The balance of forces exerted on the mechanism by the rod 10 is disturbed. The plate 15 rotates around its pin 31 and opens the contacts, as shown in FIG. 5 and 6. A hole 25, made inside the latch 19, allows the latch to rotate around the pin 20, and this latch hole 25, in cooperation with the holes 24, 26 of the plate 15, allows the plate to rotate, while the handle is still held in the position when the contacts are closed.

Then, the handle spring moves it to the contact opening position, and the rod moves the latch to its initial position, as shown in FIG. 7. The spring 27 springing the latch and returning the lever then moves to a position where the latch can snap into the lever when the handle is actuated to close the contacts. The holes 24, 26 provided in the plate 15 participate in the direction of movement of the rod 10 to the position in which it presses the plate.

Thus, according to the invention, in the normal operating position of the electric circuit without a malfunction in the circuit, the rod presses on the contact support plate and on the latch, while the relative positions of the two supporting surfaces and the lever ratio X and Υ are optimized so that the latch's latching force is reduced to an exact minimum.

For this, the system contains two reduction gear stages. According to the first stage, the force of the mechanism is largely perceived by the plate and, to a lesser extent, by the latch. According to the second stage, due to the lever means on the latch, the force decreases or decreases on the trip lever.

Due to this, the force required to interrupt the snap can be reduced to a lower value than in solutions according to the prior art.

Using the invention, it is possible to reduce the size of the products while maintaining or improving the performance of the device due to the fact that it is possible to reduce the size of the magnetic and thermal protective devices. This reduces the heat given off by thermal protective devices. The operation of magnetic trip devices becomes faster and better as dynamic stresses are reduced.

The reduction in the latching force also makes it possible to reduce the support surface of the latch on the lever and thereby the thickness of the latch and the release lever.

Reducing the latching force also means the possibility of making a latch of a cut metal plate, as well as the possibility of making a latch of a thin metal plate. The small thickness of the latch and the lever also allows you to install a screen for protection against contamination between the rod, on the one hand, and the snap zone between the latch and the lever, on the other hand.

It should also be noted that due to the presence of the bias spring, the chain of dimensions that ensure the latch latches on the lever is simplified.

A single spring is used to perform two functions, namely to return the lever to its original position and create a snap gap.

Similarly, due to the presence of the screen, the snapping zone is not damaged due to contamination due to opening. The performance of the circuit breaker is stored over time.

The invention is applicable to any electrical device containing a mechanism of the type indicated above, such as a circuit breaker, a switch, a differential switch, an interrupt switch, auxiliary contacts, including modular products, etc.

- 3 014194

Naturally, the invention is not limited to the described and depicted embodiments, which are given only as an illustration.

On the contrary, the invention covers all technical equivalents of the described means, as well as their combinations, if they are made in accordance with the idea of the invention.

Claims (11)

CLAIM 1. The working device of an electrical protective device placed in an insulating casing containing a pair of fixed and movable contacts, wherein said movable contact is designed to be switched on either manually using the handle or automatically containing a transmission rod connected to the handle, a supporting mechanism of the movable contact comprising a support plate mounted rotatably on an axis and having a breakable mechanical link to a transfer rod, and a trip lever, yn driven by a release mechanism to open the mechanical link in the event of a malfunction, which leads to the automatic release of the device regardless of the handle and opening of the contacts, while the unlocked mechanical link is formed by means of a retaining cut-out in the release lever, working in conjunction with a latch that can be rotated on a plate pin, characterized in that in the latching position of the latch, the transmission rod (10) is configured to be pressed force on the plate (15) and on the latch (19), while the relative positions of the two supporting surfaces on the plate (15) and the latch (19) provides the formation of two levers that distribute the forces from the transfer rod so that the force applied to the latch less force exerted on the plate. 2. The device according to claim 1, characterized in that the relative positions of the two supporting surfaces relative to the plate and the latch and the ratio of the two levers are selected so that the force applied to the latch is about seven times less than the force applied to the plate. 3. The device according to any one of claims 1 or 2, characterized in that the latch (19) and the release lever (16) are made with a thickness that allows the screen to be protected from contamination between the rod and the snap zone, between the latch and the release lever. 4. Device according to any one of claims 1 to 3, characterized in that the latch (19) is made of a cut metal plate or of plastic. 5. The device according to any one of claims 1 to 4, characterized in that the latch (19) and the plate (15) contain holes (24, 25, 26) to ensure rotation of the plate (15) when automatic disengagement occurs, while how the rod (10) is locked in the closed position of the contacts by the handle. 6. The device according to any one of claims 1 to 5, characterized in that the plate (15) also contains holes (24, 26), designed to guide the passage of the rod (10) in its original position, pressing against the plate (15) when the handle (6) returns to the open position of the contacts after automatic disengagement. 7. The device according to claim 5, characterized in that the hole (25) of the latch (19) is U-shaped. 8. A device according to any one of claims 5 or 6, characterized in that the hole provided in the plate is formed by two elongated holes (24, 26) forming U. 9. The device according to any one of claims 1 to 8, characterized in that it comprises a spring (27) with two branches (28, 29) fixed on the lever (16), containing the first branch (28), designed to move the lever ( 16) back to its initial position of readiness for latching after the disengagement has occurred, and the second branch (29), designed to move the latch (19) to the preferred position, in which there is sufficient clearance between the latch (19) and the lever (16) to facilitate latching latches on the specified lever after automatic disengagement tions. 10. A device according to any one of claims 3 to 5, characterized in that said screen is cast together with a trip lever (16). 11. An electrical switching device comprising a working device according to any one of paragraphs.110.