Disconnecting switch

Abstract

To provide a disconnecting switch that allows an inspector to more easily and more reliably check the quality of the state of contact between a movable contactor and a stationary contactor.SOLUTION: A twistable blade 30 having a movable contactor (blade contact 36) at its end comprises: a first side plate 31 that is in a horizontal state when the movable contactor is directed in the horizontal direction, and a second side plate 32 that is in the horizontal state when the movable contactor is directed in the vertical direction. A first mark 51 is provided on a surface of the first side plate 31 directed downward when the movable contactor is directed in the horizontal direction, and a second mark 52 different from the first mark 51 is provided on a surface of the second side plate 32 directed downward when the movable contactor is directed in the vertical direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a circuit breaker for opening and closing a power line, and particularly to a horizontal two-point disconnector in which the operation of the blade is a twisting type.

Background Art

[0002] In this type of circuit breaker, when the rotating blade twists, the movable contact at the tip and the fixed contact on the receiving side come into contact at a regular position, allowing current to flow.

[0003] That is, the blade is a long conductive member extending in the horizontal direction, and the middle part thereof is supported on a rotating insulator via a twisting device. As a result, the blade rotates around the axis of the rotating insulator together with the rotating insulator by the power from the drive source. When the blade rotates and displaces to the insertion position, both ends of the blade come into contact with the fixed contacts arranged on both sides. Also, when the blade rotates and displaces to the cut position, both ends of the blade are separated from the fixed contacts.

[0004] Further, the blade is rotatable about an axis extending in the extending direction by a twisting device. While the blade moves from the cut position to the insertion position (when approaching the fixed contact), the blade rotates 90 degrees and is inserted between a pair of upper and lower finger contacts, which are fixed contacts, while changing its orientation from the horizontal direction to the vertical direction and comes into contact with the fixed contacts (see Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, since the circuit breaker is left outdoors for a long time, the rotation mechanism may not move smoothly, and the direction of the movable contact may not reach the intended direction. In such a situation, the contact state between the movable contact and the fixed contact becomes incomplete, resulting in problems such as poor conduction and overheating.

[0007] Therefore, conventionally, regular inspections are carried out, and the inspector visually checks the contact state between the movable contact and the fixed contact. However, circuit breakers are often grounded at a high position from the ground, and when the blade is in the inserted position, the movable contact is inserted between the finger contacts, making it difficult to visually confirm the quality of the contact state.

[0008] The present invention has been made in view of such circumstances, and the main object is to provide a circuit breaker that enables an inspector to more easily and reliably grasp the quality of the contact state between the movable contact and the fixed contact.

Means for Solving the Problem

[0009] To achieve the above object, the circuit breaker according to the present invention includes a fixed contact to which a power line is connected, a plate-shaped movable contact that faces the horizontal direction when separated from the fixed contact, and is inserted between the terminals of the fixed contact while changing its direction from the horizontal direction to the vertical direction when approaching the fixed contact to contact the fixed contact, a rotatable blade that supports the movable contact at its end so that the movable contact moves away from or approaches the fixed contact, and is a circuit breaker having the blade includes a first side plate that is horizontal when the movable contact is directed in the horizontal direction, and a second side plate that is horizontal when the movable contact is directed in the vertical direction, a first mark is provided on the surface of the first side plate that faces downward when the movable contact is directed in the horizontal direction, When the movable contact is directed in the vertical direction on the second side plate, a second mark is provided on the surface directed downward. It is characterized by this.

[0010] Here, the first mark and the second mark are not particularly limited, but the first mark may be a colored paint, and the second mark may be a colored paint of a color different from that of the first mark.

[0011] Therefore, if the twisting state of the blade is normal, at the cutting position, the first side plate is in a horizontal state, and the second side plate is in a vertical state. So, when looking up at the blade from directly below, only the first mark provided on the surface directed downward of the first side plate should be visible. Also, if the twisting state of the blade is normal, at the insertion position, the first side plate is in a vertical state, and the second side plate is in a horizontal state. So, when looking up at the blade from directly below, only the second mark provided on the surface directed downward of the second side plate should be visible.

[0012] However, if there is an abnormality in the twisting operation of the blade and one side plate does not become horizontal and the other side plate does not become vertical, when looking at the blade from below, both the first mark provided on the surface directed downward when the first side plate becomes horizontal and the second mark provided on the surface directed downward when the second side plate becomes horizontal will be visible.

[0013] Therefore, in such a case, when looking at the blade from below, if the ratio of the exposed amount of the first mark (the projected area when looking at the first mark from below) to the exposed amount of the second mark (the projected area when looking at the second mark from below) deviates from the allowable range, it can be determined that there is an abnormality.

[0014] Furthermore, the present invention includes a movable side stopper provided on the movable contact and a fixed side stopper provided in the vicinity of the fixed contact so as to be able to contact the movable side stopper. A third mark may be provided on the surface of the movable side stopper that contacts the fixed side stopper.

[0015] In such a configuration, when the blade rotates normally and reaches the insertion position, the movable stopper should contact the fixed stopper, and the third mark provided on the contact surface of the movable stopper should become invisible. However, if there is an abnormality in the rotation operation and the third mark appears without being hidden at the insertion position of the blade, it becomes possible to grasp the abnormal state by visually checking this. That is, it becomes possible to determine the normality based on the presence or absence of the appearance of the third mark at the insertion position of the blade.

Advantages of the Invention

[0016] As described above, according to the present invention, in a blade provided with a first side plate that becomes horizontal when the movable contact is directed in the horizontal direction and a second side plate that becomes horizontal when the movable contact is directed in the vertical direction, a first mark is provided on the surface facing downward when the movable contact of the first side plate is directed in the horizontal direction, and a second mark is provided on the surface facing downward when the movable contact of the second side plate is directed in the vertical direction. Therefore, an inspector can easily and surely grasp the quality of the contact state between the movable contact and the fixed contact according to the quality of the twisting state of the blade.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Best Mode for Carrying Out the Invention

[0018] Hereinafter, embodiments of the circuit breaker of the present invention will be described with reference to the drawings.

[0019] In FIG. 1, as an example of the circuit breaker, a horizontal two-point circuit breaker is shown. In this embodiment, for the sake of convenience of explanation, the directions of up, down, left, right, front, and rear are defined as shown by the arrows in the lower left of FIG. 1.

[0020] In FIG. 1, the circuit breaker 1 includes three circuit breaking units 4 for three phases installed on a pair of beam portions 3 fixed on a pair of mounting tables 2. Each circuit breaking unit 4 is composed of a base 11, a rotary insulator device 12, a pair of fixed insulator devices 13, fixed contacts (a pair of finger contacts) 14 provided on each fixed insulator device 13, and a blade 30 provided on the rotary insulator device 12.

[0021] Also, in each disconnection unit 4, for example, the power source side of the power line is connected to the left fixed contact 14, and the load side of the power line is connected to the right fixed contact 14. Further, the circuit breaker 1 includes a drive device 15 that rotationally drives the rotary insulator device 12 and the blade 30 of each disconnection unit 4. Also, the circuit breaker 1 includes a transmission mechanism that transmits the power for rotationally driving the rotary insulator device 12 and the blade 30 of each disconnection unit 4 by the drive device 15. This transmission mechanism includes a drive rod 16 extending from the drive device 15, a transmission member 17 that transmits the rotational power of the drive rod 16 to the rotary insulator device 12, a rotational operation member 18, a pair of transmission rods 19, and a connection portion 20 provided at the base end of the rotary insulator device 12 and connected to the pair of transmission rods 19.

[0022] In each disconnection unit 4, the base 11 has a mounting surface that extends in the horizontal direction and is fixed on the pair of beam portions 3.

[0023] Also, in each disconnection unit 4, the rotary insulator device 12 is disposed at an intermediate portion in the left - right direction on the base 11 and extends in the vertical direction (up - down direction). The rotary insulator device 12 has an insulator formed of porcelain and insulates between the base 11 and the blade 30.

[0024] The base end side of the rotary insulator device 12 is attached to the base 11 via a bearing device 23. Thereby, the rotary insulator device 12 is rotatable about the vertical axis X as the rotation axis.

[0025] Also, in each disconnection unit 4, the pair of fixed insulator devices 13 are respectively disposed apart from both sides of the rotary insulator device 12 on the base 11. Each fixed insulator device 13 extends in the vertical direction (up - down direction), and its base end side is non - rotatably fixed to the base 11 via a fixing member 24. Each fixed insulator device 13 has an insulator formed of porcelain and insulates between the base 11 and the fixed contact 14 provided at the upper end.

[0026] Figure 2 shows a state where the blade 30 is attached to the upper end of the rotary insulator device 12 in each disconnection unit 4 via the twisting device 40. The blade 30 is formed of a conductive material and is formed in a long plate shape extending in the horizontal direction as shown in FIG. 3. The middle portion of the blade 30 in the horizontal direction is rotatably attached to the upper end of the rotary insulator device 12 via the twisting device 40 about the X axis.

[0027] Blade contacts (movable contacts) 36 formed by bending flat plate-shaped members having conductivity are attached to both ends of the blade 30, respectively.

[0028] A knock pin 37 and a movable side stopper 38 are attached to the base end portion of each blade contact 36. The knock pin 37 attached to one of the blade contacts 36 located on the left side in FIGS. 2 and 3 is attached so as to extend upward from the blade contact 36 when the blade 34 is in the cut position described later. Further, the movable side stopper 38 attached to the one blade contact 36 is attached so as to extend upward from the blade contact 36 when the blade 34 is in the insertion position described later (that is, when the blade is in the upright vertical state).

[0029] Also, the knock pin 37 attached to the other blade contact 36 located on the right side in FIGS. 2 and 3 is attached so as to extend downward from the blade contact 36 when the blade 30 is in the cut position. Further, the movable side stopper 38 attached to the other blade contact 36 is attached so as to extend downward from the blade contact 36 when the blade 34 is in the insertion position.

[0030] The twisting device 40 has a mechanism for rotating the blade 30 about the Y-axis perpendicular to the X-axis. The twisting device 40 includes a support base 41 fixed to the upper end of the rotary insulator device 12 and a support member 42 fixed on the support base 41. The middle part of the blade 30 is rotatably supported by the support member 42 about the Y-axis extending in the horizontal direction as the rotation axis. Further, the twisting device 40 includes a guide member 43 for guiding the rotation of the blade 30 about the Y-axis and restricting the rotation range.

[0031] Furthermore, the twisting device 40 includes a safety device 44. This safety device 44 is a device that assists the necessary rotation of the blade 30 about the Y-axis by a built-in spring and suppresses the unnecessary rotation of the blade 30 about the Y-axis.

[0032] In FIG. 1, when the rotational power is transmitted from the drive device 15, this power is transmitted to the drive rod 16, whereby the drive rod 16 rotates. The rotation of the drive rod 16 is transmitted to the rotary insulator device 12 of the breaking unit 4 arranged closest to the front of the circuit breaker 1 via the transmission member 17 and the rotation operation member 18, whereby the rotary insulator device 12 rotates about the X-axis. The rotation of the rotary insulator device 12 is transmitted to the rotary insulator device 12 of the breaking unit 4 arranged in the middle and the rotary insulator device 12 of the breaking unit 4 arranged furthest to the rear via the transmission rod 19, whereby each rotary insulator device 12 rotates about the X-axis. In this way, when the rotary insulator device 12 rotates in each breaking unit 4, the blade 30 rotates about the X-axis accordingly.

[0033] Incidentally, the blade 30 includes a first side plate 31 that becomes horizontal when the plate surface of the blade contact (movable contact) 36 is horizontal (when the perpendicular to the plate surface is oriented vertically), and a second side plate 32 that becomes horizontal when the plate surface of the blade contact 36 is oriented vertically (when the perpendicular to the plate surface is oriented horizontally). The first side plate 31 and the second side plate 32 are connected at their respective side edges and are formed of an angle member integrated into an L-shaped cross section. In this example, the width and length of the first side plate 31 are formed to be equal to the width and length of the second side plate 32.

[0034] The blade contacts 36 provided at both ends of the blade 30 are provided so as to be parallel to the first side plate 31. When in the cutting position, as shown in FIG. 2, each blade contact 36 is in a horizontal state. In this state, as described above, the knock pin arranged on the left side of the blade faces upward, and the knock pin arranged on the right side of the blade faces downward. Also, each movable side stopper is provided parallel to the blade contact 36 and perpendicular to the Y-axis so as to face the fixed contact 14 side.

[0035] When the blade 30 in this cutting position rotates toward the insertion position and the blade contact 36 approaches the fixed contact 14, as shown in FIG. 4(a), each knock pin 37 contacts the pushing member 25 (in the figure, the knock pin 37 oriented downward in the cutting position contacts the pushing member 25). At this stage, the blade contact 36 is still in a horizontal state. As shown in FIG. 4(b), the first side plate 31 of the blade 30 is horizontal and the second side plate 32 is vertical. The lower surface of the first side plate 31 is oriented downward and is visible from below.

[0036] After that, as the blade 30 further rotates, as shown in FIG. 4(c), the knock pin is pushed and begins to tilt, so the blade 30 begins to rotate about the Y-axis. As a result, each blade contact 36 begins to rise. At this stage, as shown in FIG. 4(d), the blade 30 is in an inclined state with both the first side plate 31 and the second side plate 32, and the lower surface of each side plate is directed obliquely downward and is visible from below.

[0037] When the rotation amount of the blade 30 about the Y-axis exceeds a predetermined amount (for example, 45 degrees), the knock pin 37 separates from the pushing member 25, and the blade 30 is pushed by a spring built into the safety device 44. The blade 30 continues to rotate about the Y-axis. As shown in FIG. 4(e), the blade contact 36 rises vertically. In this state, the knock pin 37 is in the horizontal direction, the first side plate 31 of the blade 30 is in the vertical state, the second side plate 32 is in the horizontal state, and the lower surface of the second side plate 32 is directed downward and is visible from below. Also, the movable side stopper 38 is directed in the vertical direction (downward) and abuts against the fixed side stopper 26 integrated with the pushing member 25 from the back side. Thereby, the rotation of the blade 30 about the Y-axis is defined within the range from the horizontal position to the vertical position of the blade contact 36.

[0038] When each blade contact 36 rises vertically, the side edge portions of each blade contact 36 press the fixed contact 14 outward in the vertical direction. Therefore, each blade contact 36 will surely contact the fixed contact 14. When the blade contact 36 rises vertically in this way, the blade 30 reaches the insertion position, and the power supply side of the power line connected to the left fixed contact 14 of the disconnection unit 4 and the load side of the power line connected to the right fixed contact 14 are electrically connected via the blade 30.

[0039] FIG. 5 is a view of the above-described operation as seen from below the blade. When the blade 30 moves from the cutting position to the insertion position, due to the power generated by the drive device 15, the blade 30 of each disconnection unit 4 simultaneously performs a rotational operation with the X-axis as the rotation axis and a rotational operation with the Y-axis as the rotation axis as shown in FIG. 5(a). In the state where it reaches the insertion position, as shown in FIG. 5(b), the blade 30 rotates 90 degrees with the Y-axis as the rotation axis, and the blade contact 36 is inserted between the fixed contacts 14.

[0040] Therefore, when looking up from below, the blade 30 shifts from a state where the lower surface of the first side plate 31 is visible to a state where the lower surface of the second side plate 32 is visible.

[0041] On the other hand, when the blade 30 rotates from the insertion position to the cutting position with the X-axis as the rotation axis, the movable side stopper 38 abuts against the fixed side stopper 26 of the pushing member 25. Therefore, it is pushed by this pushing member 25 (fixed side stopper 26), and the blade 30 starts to rotate in a direction that makes the movable side stopper 38 horizontal with the Y-axis as the rotation axis.

[0042] Then, the blade contact 36 moves out from the fixed contact 14. When the amount of rotation of the blade 30 with the Y-axis as the rotation axis exceeds a predetermined amount (for example, 45 degrees), the blade 30 is pushed by a spring built into the safety device 44, and the blade 30 continues to rotate with the Y-axis as the rotation axis. When the blade 30 reaches the cutting position, the blade contact 36 is returned to the horizontal state. As a result, the power supply side of the power line connected to the left fixed contact 14 of each disconnection unit 4 and the load side of the power line connected to the right fixed contact 14 are disconnected.

[0043] As described above, the blade 30 twists so that the blade contact 36 alternately switches between the cut state where the blade contact 36 is in a horizontal state and the insertion state where the blade contact 36 is in a vertical state and abuts against the fixed contact 14. However, if for some reason the twisting mechanism does not move smoothly and the orientation of the blade contact 36 does not reach the intended orientation, the contact state between the blade contact 36 and the fixed contact 14 becomes insufficient, resulting in poor contact, conduction failure, and overheating.

[0044] Therefore, a configuration is provided to easily and surely visually confirm the position of the blade 30 in the turning direction (rotation direction around the Y-axis) at the insertion position of the blade 30 or the position in the turning direction of the blade 30 at the cut position. That is, taking advantage of the fact that the blade 30 is composed of an angle member with an L-shaped cross-section, a mark is provided on the surface of this angle member to confirm the rotation state of the blade.

[0045] Specifically, a first mark 51 is provided on the surface facing downward when the blade contact 36 is directed horizontally on the first side plate 31 of the blade 30, and a second mark 52 is provided on the surface facing downward when the blade contact 36 is directed vertically on the second side plate 32.

[0046] Here, the first mark 51 and the second mark 52 can adopt colors, patterns, characters, scales, etc. The first mark 51 and the second mark 52 are preferably different. Here, different colors are used, with the first mark 51 being a colored paint of an arbitrarily selected color and the second mark 52 being a colored paint of a color different from the first mark.

[0047] The first mark 51 is preferably provided with a width substantially the same as the width of the first side plate 31, and the length can be provided over substantially the entire first side plate 31 or can be provided over a predetermined range in the middle part that is easy to see from below.

[0048] Similarly, the second mark 52 is preferably provided with a width substantially the same as that of the second side plate 32, and the length may be provided over substantially the entire length of the second side plate 32 or may be provided over a predetermined range in an intermediate portion that is easy to view from below.

[0049] Therefore, when the blade contact 36 is in contact with the fixed contact 14 at the normal position in the state where the blade 30 is in the insertion position, that is, when the blade contact 36 is in the vertical state, as shown in FIG. 6(a), when looking up at the blade 30 from below, only the second mark 52 provided on the lower surface of the second side plate 32 can be seen. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed directly below the blade 30 is 0:100.

[0050] Also, in the case of a movement within an allowable range, such as when play is provided in the twisting operation, that is, when the blade contact 36 is in contact with the fixed contact 14 while being slightly inclined from the vertical, as shown in FIG. 6(b), when looking up at the blade 30 from below, the second mark 52 provided on the lower surface of the second side plate 32 occupies most of the view, but the first mark 51 provided on the first side plate 31 can also be seen to some extent. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed directly below the blade 30 is, for example, 5:95.

[0051] On the other hand, when an abnormality occurs in the twisting operation of the blade 30 and the blade contact 36 is greatly inclined from the vertical state and inserted between the fixed contacts 14, as shown in Fig. 6(c), when looking up at the blade 30 from below, more of the first mark 51 provided on the first side plate 31 can be seen. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed from directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed from directly below the blade 30 is, for example, 30:70.

[0052] Therefore, when this ratio (α = area of the first mark / area of the second mark) exceeds the ratio of the allowable range (A), for example, if 10:90 is taken as the ratio for distinguishing the quality of the contact state, when the proportion of the projected area of the first mark 51 becomes larger than this (or when the proportion of the projected area of the second mark 52 becomes smaller than this), it becomes possible to determine the abnormality in the twisted state of the blade 30.

[0053] Also, when the blade 30 is in the cut position and the blade contact 36 is horizontal under normal conditions, as shown in Fig. 7(a), when looking up at the blade from below, only the first mark 51 provided on the lower surface of the first side plate 31 can be seen. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed from directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed from directly below the blade 30 is 100:0.

[0054] Also, when there is play in the twisting operation or it is within the allowable range of movement, that is, when the blade contact 36 is slightly inclined from the horizontal state, as shown in Fig. 7(b), when looking up at the blade 30 from below, the first mark 51 provided on the lower surface of the first side plate 31 occupies most of the view, but the second mark 52 provided on the second side plate 32 can also be seen to some extent. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed from directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed from directly below the blade 30 is, for example, 95:5.

[0055] On the other hand, when an abnormality occurs in the twisting operation and the blade contact 36 is greatly inclined from the horizontal state, as shown in FIG. 7(c), when looking up at the blade 30 from below, more of the second marks 52 provided on the second side plate 32 can be seen. That is, the ratio of the projected area of the first mark 51 provided on the first side plate 31 when viewed from directly below the blade 30 to the projected area of the second mark 52 provided on the second side plate 32 when viewed from directly below the blade 30 is, for example, 70:30.

[0056] Therefore, when this ratio (β = area of the second mark / area of the first mark) exceeds the ratio of the allowable range (B), for example, if 90;10 is taken as the ratio for distinguishing the quality of the twisted state, when the proportion of the second mark 52 becomes larger than this, it becomes possible to determine the abnormality in the twisted state of the blade 30.

[0057] In automating the above determination, at at least one of the insertion position and the cutting position of the blade 30, the portion of the blade 30 with marks is photographed by the photographing device 60 from below the blade 30, the photographed image of this photographing device 60 is input to an arithmetic device for image processing, the ratio of the projected areas of the first mark 51 and the second mark 52 (the proportion of the marks exposed when viewed from below) is calculated, and the presence or absence of an abnormality may be determined based on this calculation result.

[0058] The photographed image by the photographing device 60 may be such that the photographing device is installed below the blade 30 at at least one of the insertion position and the cutting position of the blade 30 and automatically photographs, or the inspector may manually photograph from below the blade 30 each time for inspection. The arithmetic device is input with this photographed image and the information on the position (insertion position or cutting position) of the blade 30 when the photographed image is taken. Thereby, for example, a determination process as shown in FIG. 8 may be performed.

[0059] The determination process by the arithmetic unit will be described below. When the arithmetic unit inputs the image data obtained by photographing the blade 30 from below together with the position information (insertion information or cut information) of the blade 30 at the time of photographing (step S50), it determines at which position the input image data is an image of the blade 30 (step S52). If it is determined that the image data is the image data when the blade 30 is at the insertion position, the processes of steps S54 to S60 are performed. If it is determined that the image data is the image data when the blade 30 is at the cut position, the processes of steps S64 to S70 are performed.

[0060] Specifically, when it is determined that the input image data is an image of the insertion position of the blade 30, the area ratio α of the first mark 51 and the second mark 52 displayed in the image is calculated (step S54). The area ratio α here is calculated as the projected area of the first mark 51 with respect to the projected area of the second mark 52. Then, it is determined whether the calculation result is greater than a threshold value (A) that is recognized as abnormal in advance (step S56). If it is below the threshold value, it is recognized as normal (step S58). If it is greater than the threshold value, it is recognized as abnormal (step S60).

[0061] Also, when it is determined that the input image data is an image of the cut position of the blade 30, the area ratio β of the first mark 51 and the second mark 52 displayed in the image is calculated (step S64). The area ratio β here is calculated as the projected area of the second mark 52 with respect to the projected area of the first mark 51. Then, it is determined whether the calculation result is greater than a threshold value (B) that is recognized as abnormal in advance (step S66). If it is below the threshold value, it is recognized as normal (step S68). If it is greater than the threshold value, it is recognized as abnormal (step S70).

[0062] By adopting such a pass / fail determination by the arithmetic unit, it becomes possible to reduce the determination error depending on the inspector and to take a more appropriate response.

[0063] In the above configuration, the quality of the twisting state of the blade 30 is determined by the appearance of the first mark 51 and the second mark 52 provided on the blade 30. However, in the above configuration including the movable-side stopper 38 provided on the blade contact (movable contact) 36 and the fixed-side stopper 26 provided near the fixed contact 14 so as to be able to contact the movable-side stopper 38, a third mark 53 may be provided on the surface of the movable-side stopper 38 that contacts the fixed-side stopper 26.

[0064] This third mark 53 is not particularly limited, and colors, patterns, characters, scales, etc. can be adopted. Also, the marks used here may be different from or the same as the first mark 51 and the second mark 52.

[0065] In such a configuration, in a state where the blade contact 36 normally contacts the fixed contact 14 (when the blade contact 36 is in a vertical state at the insertion position of the blade 30), the movable-side stopper 38 contacts the fixed-side stopper 26, and the third mark 53 provided on the contact surface of the movable-side stopper 38 with the fixed-side stopper 26 should become invisible.

[0066] On the other hand, when an abnormality occurs in the twisting device 40 of the blade 30 and the blade 30 is in a vertical state even though the blade 30 is at the cutting position, for example, as shown in Fig. 9(a), when the blade 30 moves from this state to the insertion position, since the movable-side stopper 38 is already in a vertical state, as shown in Fig. 9(b), the movable-side stopper 38 contacts in front of the fixed-side stopper 26, and the third mark 53 remains in an exposed state. Therefore, by visually checking the presence or absence of the exposure of the third mark 53 when looking up from below, it becomes possible to grasp the abnormality in the twisting state of the blade 30. Therefore, by further adding such a configuration, it becomes possible to more reliably grasp the presence or absence of an abnormal operation of the blade 30.

[0067] In the above description, a horizontal two-point cut-off circuit breaker has been described as an example, but the present invention is also applicable to other circuit breakers equipped with a blade twisting device. Further, the present invention can be appropriately modified within a range not contrary to the gist or idea of the invention that can be read from the claims and the entire specification, and a circuit breaker with such modifications is also included in the technical idea of the present invention.

Explanation of Reference Numerals

[0068] 1 Circuit breaker 14 Fixed contact 26 Fixed-side stopper 30 Blade 31 First side plate 32 Second side plate 36 Blade contact (movable contact) 38 Movable-side stopper 51 First mark 52 Second mark 53 Third mark

Claims

1. a fixed contact to which a power line is connected, a plate-shaped movable contact that is oriented in the horizontal direction when away from the fixed contact and is inserted between the terminals of the fixed contact while changing its orientation from the horizontal direction to the vertical direction when approaching the fixed contact to contact the fixed contact, a rotatable blade that supports the movable contact at its end so that the movable contact moves away from or approaches the fixed contact, A circuit breaker having: The blade includes a first side plate that is horizontal when the movable contact is oriented in the horizontal direction, and a second side plate that is horizontal when the movable contact is oriented in the vertical direction, A first mark is provided on a surface that faces downward when the movable contact is oriented in the horizontal direction on the first side plate, A second mark is provided on a surface that faces downward when the movable contact is oriented in the vertical direction on the second side plate, The circuit breaker is characterized by the above.

2. The first mark is a colored paint, The circuit breaker according to claim 1, wherein the second mark is a colored paint having a color different from that of the first mark.

3. The circuit breaker according to claim 1 or 2, wherein when viewed from below, if the ratio of the exposed amount of the first mark to the exposed amount of the second mark deviates from the allowable range, it is determined that an abnormality exists.

4. a movable-side stopper provided on the movable contact, and a fixed-side stopper provided near the fixed contact so as to be able to contact the movable-side stopper, The circuit breaker according to claim 1 or 2, wherein a third mark is provided on a surface of the movable-side stopper that contacts the fixed-side stopper.

Images