KR20090109479A - System and method for indicating a position of an electrical distribution device - Google Patents

Abstract

PURPOSE: A system and a method for displaying a position of a distribution device are provided to display a disconnection or connection state of a circuit breaker regardless of the change of a lever using mechanical stop unit and a deflection device. CONSTITUTION: A rotation indicator(40) has a first position and a second position. The first position shows the connection state. The second position shows the disconnection state. A deflection device deflects the rotation of the indicator to the first position when the racking device is connected. The deflection device deflects the rotation of the indicator to the second position when the racking device is disconnected. A first mechanical stop unit(76) maintains the indicator at the first position when the racking device is connected. A second mechanical stop unit maintains the indicator at the second position when the racking device is disconnected.

Description

SYSTEM AND METHOD FOR INDICATING A POSITION OF AN ELECTRICAL DISTRIBUTION DEVICE}

TECHNICAL FIELD The present invention relates to a power distribution facility, and more particularly, to an indicator for a power distribution device.

Conventional power distribution installations generally have one or more circuit breakers, sometimes with multiple circuit breakers housed in drawer housings and withdrawal units in other electrical installations. Periodically, the circuit breaker withdrawal unit needs to be disconnected to facilitate maintenance and / or replacement of the associated switchgear. To facilitate disconnection or to disconnect the circuit breaker from the electrical circuit, the circuit breaker is " racked out ", that is, the disconnection portion in the circuit breaker is moved from the connecting position to the disconnecting position.

Conventional circuit breakers have three positions. The first position is the "connected position" where the primary and secondary disconnection portions of the circuit breaker are connected to the circuit. The second position is the " disconnected position " where the primary and secondary disconnect portions are disconnected. The third position is the "test position" to which the primary disconnection unit is disconnected but the secondary disconnection unit is connected. The test location allows the user to check the function of the secondary or control power supply, for example. The breaker can be racked between these three positions. When unlocked, the breaker moves from the connecting position to the disconnecting position via the test position.

The racking mechanism is provided with a circuit breaker, such as a racking shaft, which allows the mechanism to rotate to move the circuit breaker to the connecting position. Indicators of various positions are provided with the racking mechanism, which indicators are generally subject to the rotation of the racking mechanism to indicate the position. However, the asynchronous between the indicator and the racking mechanism can cause the indicator to indicate the circuit breaker's position incorrectly or incompletely, thus demonstrating inaccuracy in indicating whether the circuit breaker is fully connected or disconnected.

A system for indicating a position of a power distribution apparatus, configured to be racked in an electrically connected state in an enclosure and unlocked in an electrical disconnect state through a racking mechanism, configured according to an exemplary embodiment of the present invention, includes at least a first position and a first position. A rotatable indicator having two positions, wherein the first position represents a connected state and the second position represents a disconnected state, and the indicator rotates in response to the racking mechanism moving between the connected state and the disconnected state. Operatively connected to the racking mechanism. The system further includes a biasing device for biasing the rotation of the indicator towards the first position when the racking mechanism is in the connected state and for biasing the rotation of the indicator towards the second position when the racking mechanism is in the disconnected state. . The system adds a first mechanical stop for holding the indicator in the first position when the racking mechanism is in a connected state, and a second mechanical stop for holding the indicator in the second position when the racking mechanism is in the disconnected state. It is provided with.

Another exemplary embodiment of the present invention includes a method for indicating a racking position of a power distribution device configured to be racked to an electrical connection state in an enclosure and unlocked to an electrical disconnect state through a racking mechanism. The method includes moving the racking mechanism such that the power distribution device moves at least between the connected state and the disconnected state, and converting the translational movement of the racking mechanism into a rotational movement of the indicator, the indicator indicating at least a connected state. It has a 1st position and a 2nd position which shows a disconnection state. The method further includes biasing the indicator to rotate towards the first position when the racking mechanism is in the connected state and biasing the indicator to rotate towards the second position when the racking mechanism is in the disconnected state. The method further includes maintaining the indicator in the first position when the racking mechanism is in the connected state and maintaining the indicator in the second position when the racking mechanism is in the disconnected state.

Additional features and advantages are realized through the description of exemplary embodiments of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered part of the invention. To better understand the present invention, together with its advantages and features, reference may be made to the detailed description and drawings.

According to the present invention, the indicator for the power distribution device can clearly indicate the disconnected state and the connected state of the circuit breaker regardless of the change of the lever.

Systems and methods are provided for indicating a racking state or location of a power distribution device, such as a circuit breaker. The system has a rotating mechanical locking indicator which reliably defines the disconnection state and connection state of the circuit breaker by the use of a deflection device such as an over center spring connected thereto. In an exemplary embodiment, the racking position is tracked by a transition mechanism such as an indicator lever that has a cam profile and interacts with the racking mechanism. These positions are displayed on labels or other indicators installed on the indicator. A mechanical stop provided to define the position on the indicator cooperates with the deflection device to clearly indicate disconnection status and connection status regardless of lever variation. As used herein, " condition " of a circuit breaker or other power distribution device means any of the above devices and / or the same resulting in various connection states, such as the connection state, disconnection state, and test state described herein. Refers to the location of the various disconnecting units in the device.

Referring first to FIG. 1, a power distribution device assembly 10 constructed in accordance with an exemplary embodiment of the present invention is shown. The power distribution device assembly 10 has a housing or drawout substructure 12. The power distribution device assembly 10 further includes a power distribution device in the form of a circuit breaker 14 disposed within the lead-out infrastructure 12. In one embodiment, the circuit breaker 14 is housed in the cassette 15. The circuit breaker 14 can be easily installed in the lead out structure 12 to couple the primary and secondary electrical disconnects of the circuit breaker 14.

Referring to FIG. 2, the circuit breaker 14 has a contact arm assembly 16 mounted for operation of the circuit breaker 14. The contact arm assembly 16 has a primary disconnecting portion 18, 20 and an arm 22, at one end of which is mounted a movable contact 24. At the opposite end of the arm 22 is attached a flexible electrically conductive strap 26 made of braided copper cable. A fixed contact 28 is mounted at one end of the primary disconnecting unit 20. The strap 26 electrically couples the contact arm 22 to the primary disconnect 20 so that current can flow through the circuit breaker 14.

3 and 4, the primary disconnecting portions 18, 20 of the circuit breaker 14 when the circuit breaker 14 is in the connected state and the disconnected state are shown. In the connected state shown in FIG. 3, the primary disconnecting portions 18, 20 are electrically connected to the circuit 28 via the connector 30. In one embodiment, the connector 30 is a primary disconnect finger as is known in the art. A portion of circuit 28 is shown having a tug-in bus 32 and a load bus 34.

In the disconnection position shown in FIG. 4, the primary disconnecting portions 18, 20 are moved to disengage the connector 30 and thereby electrically disconnect the primary disconnecting portions 18, 20 from the circuit 28. The breakers and connection mechanisms described herein are exemplary only and may have any suitable form and configuration.

5, an indicator assembly 40 constructed in accordance with an exemplary embodiment of the present invention is shown. The indicator assembly 40 has an indicator drum 42 mounted on the bracket 44. The indicator drum 42 can rotate about the central axis. In this embodiment, the indicator drum 42 is a cylindrical drum, but may be of any type rotatable in accordance with the change in posture of the circuit breaker 14 and / or the racking mechanism. The over center spring 46 is connected to the indicator drum 42 at one end and to the fixing bracket 44 at the other end.

On the surface of the indicator drum 42 a plurality of indicators are arranged. These indicators are disposed on the surface to move around the axis by the rotation of the indicator drum 42. In an exemplary embodiment, the indicator has a connection position indicator 48 to indicate that the circuit breaker 14 is in a connected state in which the primary disconnecting portions 18, 20 and the secondary disconnecting portions of the circuit breaker are fully engaged. . The indicator also has a disconnection position indicator 50 to indicate that the circuit breaker 14 is in a disconnected state in which the primary disconnecting units 18 and 20 and the secondary disconnecting unit are uncoupled. In an exemplary embodiment, the indicator also has a test position indicator 52 to indicate that the circuit breaker 14 is in a test state to which the primary disconnect portions 18 and 20 are disconnected but the secondary disconnect portions are connected. When the circuit breaker 14 is racked or unracked, the indicator drum 42 rotates accordingly.

For example, the indicator drum 42 is placed in the first position to indicate that the circuit breaker 14 is in a connected state. When the circuit breaker 14 is released and disconnected, the indicator drum 42 is rotated toward the second state, that is, the disconnection position. In addition, when the indicator drum 42 rotates between the connecting position and the disconnecting position, it will rotate through an additional position, such as a test position, indicating that the circuit breaker is in a test state.

In the exemplary embodiment described herein, the power distribution device is a circuit breaker. In another exemplary embodiment, the power distribution device is a low voltage circuit breaker, such as an air circuit breaker (ACB).

In an exemplary embodiment, circuit breaker 14 includes any number of components, such as any number of primary and secondary disconnects, breaker locking mechanisms, and trip units.

In other exemplary embodiments, the circuit breaker 14 may be incorporated into the cassette 15 or other assembly. Cassette 15 and / or circuit breaker 14 may be provided with suitable electrical equipment and / or suitable for receiving the cassette 15 and any other suitable electrical equipment such as various switches and additional circuit breakers. It can be incorporated into the switchgear housing. In an exemplary embodiment, the cassette 15 is incorporated into a take-out unit that can remove the circuit breaker 14 or other switchgear as needed, for example, to facilitate maintenance or replacement of the switchgear.

Referring to FIG. 6, in an exemplary embodiment, the indicator drum assembly 40 is disposed within the cassette 15 or other housing. The cassette 15 has a front panel 54 with a display opening 56. The display opening 56 exposes one of the indicators depending on the position of the indicator drum 42. In the exemplary embodiment shown in FIGS. 5-7, the indicator drum 42 is in the disconnected position, so that the disconnected position indicator 50 is exposed through the display opening 56.

Referring again to FIG. 5, the over center spring 46 is connected to the indicator drum 42 at one end and to the fixing bracket 44 at the other end.

Referring to FIG. 7, a cassette for receiving an indicator assembly 40, a racking mechanism in operative communication with the indicator assembly 40, and a base assembly 58 on which the indicator assembly 40 and the racking mechanism are mounted ( A portion of 15) is shown.

In an exemplary embodiment, the racking mechanism has a racking shaft 60 and a screw block 62. The racking shaft 60 is coupled to a screw block 62 with a lead screw (not shown). The racking shaft 60 is rotatably coupled to the lead screw. For example, the racking shaft 60 has a male thread and the lead screw has a female thread. The threads of the racking shaft 60 engage with the corresponding threads on the lead screw of the screw block 62, so that the rotation of the racking shaft 60 imparts a linear motion to the screw block 62. The linear movement of the screw block 62 imparts motion to the primary disconnecting portions 18, 20 and the secondary disconnecting portions of the circuit breaker 14 to move the circuit breaker 14 between the connected state and the disconnected state.

In an exemplary embodiment, the cassette 15 has a conversion mechanism, such as a lever connector, for converting the linear motion of the screw block 62 into the rotational motion of the indicator drum 42. The lever connector has a lever 64 mounted to the pivot pin 66 and rotatable about it. The lever 64 has a cam groove 68 having a cam profile sufficient to cause a rotational movement of the lever 64. The cam pin 70 extends from the screw block 62 and moves linearly with the screw block 62. When the cam pin 70 moves along the cam groove 68, the lever 64 rotates around the pivot pin 66.

The other end of the lever 64 is provided with a slot 72, which is coupled to the indicator drum 42 via a suitable pin 74 (shown in FIG. 9) or other protrusion. Rotation of the lever 64 causes the indicator drum 42 to rotate about the drum axis.

These embodiments are exemplary only, and any mechanism for moving the circuit breaker disconnection portion between the connecting position and the disconnecting position may be used. In addition, the lever 64 described herein is exemplary and any suitable configuration for imparting rotational motion to the indicator drum 42 may be used.

8-11, in an exemplary embodiment, the bracket 44 is a mechanical stop disposed to cooperate with the over center spring 46 to deflect the indicator drum 42 into the disconnected and connected positions, respectively. (76, 78) is further provided. The mechanical stops 76, 78 may be of any suitable shape for stopping drum 42 rotation at a selected position. For example, the mechanical stops 76, 78 may have rigid or elastic protrusions extending from the bracket 44 and cooperating with corresponding recesses or grooves of the indicator drum 42. In the exemplary embodiment described herein, the mechanical stops 76, 78 are disposed on the bracket 44. However, these stops may be disposed on the indicator drum 42.

8 and 9, the indicator drum 42 is in the disconnected position and the over center spring 46 is directed towards the disconnected position (eg counterclockwise for FIG. 8 and clockwise for FIG. 9). Is applied, and the mechanical stop 76 holds the indicator drum 42 in the disconnection display position by preventing further rotation. When the circuit breaker 14 moves from the disconnected state to the connected state, the lever 64 rotates the indicator drum 42 toward the connected position against the tension force of the spring 46. As the drum 42 rotates, the force of the over center spring 46 increases until the over center spring 46 is stressed in an over center or mid-center state, and the over center spring 46 ) Then exerts a force to rotate the drum 42 toward the connection indication position. As the lever 64 moves to the connecting position, the over center spring 46 forces the drum 42 to deflect the drum 42 toward the mechanical stop 78, thus bringing the drum 42 into the connection mark. Keep in position.

Referring to FIGS. 10 and 11, the indicator drum 42 is in the connecting position, the drum 42 is deflected by the over center spring 46 and held in place by the mechanical stop 78.

9 and 11, in one embodiment, slot 72 defines a first width 80, and pin 74 defines a second width 82 that is narrower than the first width 80. And defines the gap between the slot 72 and the pin 74 when the indicator drum 42 is in the connecting position or disconnecting position. In one example, the second width is defined by the diameter of the pin 74. This gap degree is defined by the difference between the first width 80 and the second width 82 and may be any suitable difference. This difference allows the over center spring 46 and the mechanical stops 76 and 78 to keep the indicator drum 42 accurately in the connecting position or disconnection position regardless of the variation of the lever 64 within the clearance range. . When the circuit breaker 14 moves between the connected state and the disconnected state, the lever 64 moves past the gap. Thus, the lever 64 engages with the pin 74 to rotate the indicator drum. Thus, when the circuit breaker 14 is in the connected or disconnected state, the drum 42 is correctly maintained at each position (regardless of the variation of the lever 64), and the circuit breaker 14 is connected and disconnected. The drum 42 is moved by the lever 64 when moving between. In one embodiment, the second width 82 is considerably narrower than the first width 80, i.e. the difference between the second width 82 and the first width 80, for example, prevents binding. Greater than any width difference due to conventional manufacturing tolerances provided to do so.

Thus, in the connecting position or the disconnecting position, the drum 42 causes a change in the position of the drum 42 and thus the force of the spring 46 and the mechanical stop (regardless of the lever variation that may affect the clarity of the indicator). 76 or 78) at each display position. Thus, a clear indication of the position of the connection / disconnection is ensured, and the possibility of an unclear indication due to a mismatch between the lever and the drum is eliminated.

12 shows an exemplary method 120 for indicating the racking position of a power distribution device, such as a circuit breaker. The method 120 includes one or more steps 121, 122, 123, 124. In an exemplary embodiment, the method includes performing all the steps 121, 122, 123, 124 in the order described. However, certain steps may be omitted or added, or the order of the steps may be changed.

In a first step 121, the locking mechanism is engaged to move the circuit breaker 14 between the connected state and the disconnected state. This is achieved for example by rotating the racking shaft 60 followed by a linear movement of the screw block 62.

In a second step 122, the movement of the racking mechanism is converted to the rotational movement of the indicator drum 42, which rotates at least between the connecting position and the disconnection position in response to the racking mechanism. In one example, the movement is translated by rotating the lever 64 in response to the screw block 62 and then rotating the indicator drum 42 through the slot 72.

In the third step 123, when the racking mechanism is in the connected state or the disconnected state, the indicator drum 42 is biased toward the connected position or the disconnected position, respectively. This is achieved, for example, by connecting the indicator drum 42 to an over center spring 46 which biases the indicator drum 42 towards the connecting or disconnecting position.

In the fourth step 124, the indicator drum 42 is held in the connected position or disconnected position when the racking mechanism is in the connected state or the disconnected state, respectively. In one example, the mechanical stop 76 or 78 holds the indicator drum 42 in place against the biasing force of the over center spring 46. In this way, the over center spring 46 and the mechanical stop 76 or 78 cooperate to keep the indicator drum 42 in the connected or disconnected position independent of the lever 64.

The systems and methods described herein provide many advantages over conventional systems. Since the indicator is deflected toward the connection position or disconnection position, the indicator is guaranteed to clearly indicate the position. This is in contrast to conventional systems, for example, which rely solely on the rotation of the lever and therefore cannot rotate the indicator completely to clearly indicate its position. The systems and methods described herein are also insensitive to manufacturing tolerances because they are positioned by mechanical stops that can be designed to indicate position only when the position is actually reached.

In general, the description set forth herein is intended to enable those skilled in the art to practice the invention, including the manufacture and use of any device or system, and any method for carrying out the invention, including the best mode. Several examples are used to enable this. The scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be included within the scope of exemplary embodiments of the present invention when they have components that do not differ from the subject matter of the claims or equivalent components that do not differ substantially from the subject matter of the claims.

1 is a perspective view of a power distribution device assembly showing a circuit breaker according to an exemplary embodiment of the present invention;

2 is a side view of the circuit breaker of FIG. 1, FIG.

3 is a side view in a connected state of the primary disconnection unit of the circuit breaker of FIG. 1;

4 is a side view in a disconnected state of the primary disconnection unit of the circuit breaker of FIG. 1;

5 is a perspective view of an indicator drum assembly of the power distribution device assembly of FIG. 1 in accordance with an exemplary embodiment of the present invention;

6 is a front view of a portion of a circuit breaker cassette,

FIG. 7 is a perspective view of a portion of a circuit breaker cassette having the indicator assembly and racking mechanism of FIG. 5; FIG.

8 is a side view in disconnected position of the indicator drum assembly of FIG. 5;

9 is a side view in disconnected position of a portion of a circuit breaker cassette showing the indicator drum assembly of FIG. 5;

10 is a side view of the indicator drum assembly of FIG. 5 in a connected position;

FIG. 11 is a side view at the connecting position of a portion of the circuit breaker cassette showing the indicator drum assembly of FIG. 5; FIG.

12 is a flow chart providing an exemplary method for indicating a racking position of a power distribution apparatus.

<Explanation of symbols for the main parts of the drawings>

10 power distribution unit assembly 14 circuit breaker

15: cassette 16: contact arm assembly

18, 20: primary disconnect 22: contact arm

24: movable contact 26: strap

28; Fixed contact 28: circuit

30: connector 32: lead-in bus

34: load bus 42: indicator drum

44: bracket 46: over center spring

48: splice position indicator 50: short circuit position indicator

54: front panel 56: display opening

60: racking shaft 62: screw block

64: lever 66: pivot pin

72: slot 74: pin

76, 78: mechanical stop

Claims (10)

A system for indicating the position of a power distribution device configured to be racked in an electrical connection state in an enclosure and unlocked in an electrical disconnect state via a racking mechanism, A rotatable indicator 40 having at least a first position 48 and a second position 50, wherein the first position represents a connected state and the second position represents a disconnected state, at least between the connected state and the disconnected state. The rotatable indicator (40) operatively connected to the racking mechanism to rotate in response to the movement of the racking mechanism in the arm; A deflection device (46) for biasing the rotation of the indicator towards the first position when the racking mechanism is in the connected state and biasing the rotation of the indicator towards the second position when the racking mechanism is in the disconnected state; And A first mechanical stop 76 for retaining the indicator in the first position when the racking mechanism is in a connected state and for retaining the indicator in the second position when the racking mechanism is in a disconnected state Characterized in that it comprises a second mechanical stop (78) Location display system. The method of claim 1, And further comprising a conversion mechanism for converting the movement of the racking mechanism into the rotational movement of the indicator 40. Location display system. The method of claim 2, The deflection device cooperates with the first mechanical stop 76 to maintain the indicator 40 in the first position 48 regardless of the conversion mechanism and the indicator in the second position 50. In cooperation with the second mechanical stop 78 to maintain in Location display system. The method of claim 2, The conversion mechanism has a cam pin 70 operatively connected to the racking mechanism, and a lever 64 operatively connected to the cam pin and indicator 40. Location display system. The method of claim 2, The indicator 40 has one or more positions between the first and second positions 48, 50, the movement of the indicator to the one or more positions being dependent on the movement of the conversion mechanism. Location display system. The method of claim 1, The racking mechanism has a rotatable racking shaft 60 coupled to the lead screw, wherein the lead screw results in a linear movement between at least the connected state and the disconnected state. Location display system. 12. A method (120) of indicating a location of a power distribution device which is configured to be racked in an electrical connection state in an enclosure via a racking mechanism and unlocked in an electrical disconnect state. Moving the racking mechanism such that the power distribution device moves at least between a connected state and a disconnected state; Converting the translational movement of the racking mechanism into a rotational movement of the indicator 40, the indicator having at least a first position 48 and a second position 50, the first position representing a connection state and the A second position indicates a disconnected state; Biasing the indicator to rotate toward the first position when the racking mechanism is in a connected state and biasing the indicator to rotate towards the second position when the racking mechanism is in a disconnected state; And Maintaining the indicator in the first position when the racking mechanism is in the connected state and maintaining the indicator in the second position when the racking mechanism is in the disconnected state. How to show location. The method of claim 7, wherein The indicator 40 is held in the first position 48 when the racking mechanism is in the connected state, and is maintained in the second position 50 regardless of the transformation. How to show location. The method of claim 7, wherein The conversion includes rotating the lever 64 in response to the movement of the racking mechanism, the lever being operatively connected to the cam pin 70 and the indicator 40, the cam pin being connected to the racking mechanism. Characterized in that How to show location. The method of claim 7, wherein The indicator 40 has one or more positions between the first and second positions 48, 50, wherein the movement of the indicator to the one or more positions is subject to the transformation. How to show location.

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