EP4260353A1

EP4260353A1 - Locking device and switchgear

Info

Publication number: EP4260353A1
Application number: EP20964657.9A
Authority: EP
Inventors: Deguang LAI; Ruiying HUANG; Shihan Zhang; Longxiang ZHANG
Original assignee: ABB Schweiz AG
Current assignee: ABB Schweiz AG
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2023-10-18
Also published as: EP4260353A4; WO2022120719A1; CN116420290A

Abstract

A locking device (10) and a switchgear (100). The locking device (10) comprises a holder (102); a bolt (104) supported by the holder (102) and being movable with respect to the holder (102) along a length direction (X) of the bolt (104), the bolt (104) comprising a groove (120) extending along the length direction (X) of the bolt (104) and a bolt head (109) adapted to move outside of the holder (102) and retract back into the holder (102); a movable plate (106) partially arranged in the groove (120) and being movable with respect to the bolt (104) along a vertical direction (Y) normal to the length direction (X) of the bolt (104), the movable plate (106) comprising a first inclined part (113) adapted to interact with an end of the groove (120) when the movable plate (106) is pushed towards the holder (102), such that the bolt (104) moves with respect to the holder (102) along the length direction (X) of the bolt (104) and the bolt head (109) retracts back into the holder (102); and an elastic resetting element (108) arranged on the bolt (104) and configured to reset the bolt (104) when the movable plate (106) is released such that the bolt head (109) moves outside of the holder (102).

Description

LOCKING DEVICE AND SWITCHGEAR

FIELD

Embodiments of the present disclosure generally relate to the field of locking devices, and more particularly, to a locking device and a switchgear comprising the locking device.

BACKGROUND

Circuit breakers are the main electrical components installed in a switchgear. There are two positions for a circuit breaker in the switchgear, i.e., a working position and a test position. At the working position, a main contact of the circuit breaker is connected to a main power line, and the main power line may be opened or closed via the circuit breaker. At the test position, the main contact of the circuit breaker is not connected to the main power line, and a control circuit of the circuit breaker can be tested without energizing the main power line. The circuit breaker can be pulled between the working position and the test position in the switchgear, so as to perform the corresponding operations.
For a conventional switchgear, the circuit breaker can be operated by an operator when a door of the switchgear is opened. Since the circuit breaker and some other electrical components of the switchgear are high voltage components, contacting these components may cause great harm to the operator.
With the improvement of customers’ safety awareness, the customers may hope that their original switchgears can be updated. For example, most customers may need a locking function for preventing entry of a live space of the switchgear by mistake. That is, when the circuit breaker (CB) leaves the test position in the switchgear, the door of the switchgear should not be able to be opened.
There is a known solution to achieve the locking function mentioned above. In this solution, a locking mechanism is provided. This locking mechanism includes a crank fixed on a side of a switchgear through a bolt. The crank is rotatable around the bolt. Two ends of the crank are provided with hooks. When the circuit breaker is in the working position, the hook at the first end of the crank is coupled to the front panel of the circuit breaker, and the hook at the second end of the crank hooks a locking part on a door of the switchgear, such that the door is locked. When the circuit breaker leaves the working position and moves to the test position, the first end of the crank is pushed such that the hook at the second end of the crank is released from the locking part of the door of the switchgear and thus the door is opened.
However, due to the large size of the crank and the complex structure of the locking mechanism, it is very difficult to install the locking mechanism on the customers’ original switchgears on the site, and significant changes need to be made to the switchgear.
Thus, there is a need for an approach for preventing entry of the live space of the switchgear by mistake in a manner that is simple, low cost, and user friendly.
SUMMARY
In view of the foregoing problems, various example embodiments of the present disclosure provide a locking device for preventing entry of the live space of the switchgear by mistake in a manner that is simple, low cost, and user friendly.
In a first aspect of the present disclosure, example embodiments of the present disclosure provide a locking device. The locking device comprises a holder; a bolt supported by the holder and being movable with respect to the holder along a length direction of the bolt, the bolt comprising a groove extending along the length direction of the bolt and a bolt head adapted to move outside of the holder and retract back into the holder; a movable plate partially arranged in the groove and being movable with respect to the bolt along a vertical direction normal to the length direction of the bolt, the movable plate comprising a first inclined part adapted to interact with an end of the groove when the movable plate is pushed towards the holder, such that the bolt moves with respect to the holder along the length direction of the bolt and the bolt head retracts back into the holder; and an elastic resetting element arranged on the bolt and configured to reset the bolt when the movable plate is released such that the bolt head moves outside of the holder. With such an arrangement, the structure of the locking device is compact, and the locking device is adapted to be installed onto a door of a switchgear, thereby preventing entry of the live space of the switchgear by mistake in a manner that is simple, low cost, and user friendly.
In some embodiments, the bolt comprises a first portion and a second portion extending along the length direction of the bolt and connected to each other, the diameter of the first portion is smaller than that of the second portion, and the elastic resetting element comprises a spring arranged around the first portion, a first end of the spring is against a first side of the holder, and a second end of the spring is against the second portion.
In some embodiments, the bolt head is arranged on the second portion of the bolt and adapted to move outside of a second side of the holder opposite to the first side for a predetermined distance when the movable plate is released.
In some embodiments, the groove of the bolt is arranged in the second portion of the bolt and extends into the bolt head, and the groove comprises a second inclined part arranged at an end of the groove away from the bolt head and adapted to engage with the first inclined part.
In some embodiments, the inclination angle of the second inclined part is substantially equal to that of the first inclined part.
In some embodiments, the holder comprises a first holding portion provided with a first hole and a second holding portion provided with a second hole, the first holding portion and the second holding portion are arranged opposite to each other, and the bolt extends through the first hole and the second hole.
In some embodiments, the holder further comprises a bottom portion arranged between the first holding portion and the second holding portion, and the holder is generally of a U-shape.
In some embodiments, the bottom portion is provided with fixing holes for fixing the holder onto a plane structure.
In some embodiments, the movable plate comprises a first movable portion and a second movable portion connected to the first movable portion, the first inclined part is arranged at a first side of the first movable portion.
In some embodiments, the movable plate is provided with an unlocking hole arranged at an end of the second movable portion opposite to the first movable portion and adapted to be pulled such that the bolt head retracts back into the holder.
In some embodiments, the movable plate is provided with a stop pin arranged on the second movable portion and adapted to limit the moving range of the movable plate with respect to the bolt along the vertical direction.
In some embodiments, when the stop pin is close to the bolt, the bolt head moves outside of the holder for a predetermined distance, and when the stop pin is away from the bolt (104) , the bolt head retracts back into the holder.
In some embodiments, the holder is provided with a second groove through which the second movable portion of the movable plate extends.
In a second aspect of the present disclosure, example embodiments of the present disclosure provide a switchgear comprising the locking device according to the first aspect of the present disclosure, wherein the locking device is arranged on a door of the switchgear.
It is to be understood that the Summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.
DESCRIPTION OF DRAWINGS
Through the following detailed description with reference to the accompanying drawings, the above and other objectives, features and advantages of the example embodiments disclosed herein will become more comprehensible. In the drawings, several example embodiments disclosed herein will be illustrated in an examplary and in a non-limiting manner, wherein:
FIG. 1 is a perspective view of a locking device in accordance with an embodiment of the present disclosure;
FIG. 2 is a side view of the locking device as shown in FIG. 1;
FIG. 3 is a bottom view of the locking device as shown in FIG. 1;
FIG. 4 is a top view of the locking device as shown in FIG. 1;
FIG. 5 is a bottom view of a locking device in accordance with an embodiment of the present disclosure;
FIG. 6 is a side view of the locking device as shown in FIG. 5;
FIG. 7 is a top view of the locking device as shown in FIG. 5;
FIG. 8a is a perspective view of a movable plate in accordance with an embodiment of the present disclosure;
FIG. 8b is a side view of the movable plate as shown in FIG. 8a;
FIG. 9a is a perspective view of a bolt in accordance with an embodiment of the present disclosure;
FIG. 9b is a bottom view of the bolt as shown in FIG. 9a;
FIG. 9c is a side view of the bolt as shown in FIG. 9a;
FIG. 9d is a cross sectional view of the bolt as shown in FIG. 9c;
FIG. 10a is a perspective view of a switchgear in accordance with an embodiment of the present disclosure;
FIG. 10b is a side view of the switchgear as shown in FIG. 10a;
FIG. 10c is a schematic view of the switchgear as shown in FIG. 10b with the door of the switchgear being removed;
FIG. 10d is a partial enlarged view of the portion A as shown in FIG. 10c;
FIG. 10e is a partial enlarged view of the portion B as shown in FIG. 10a;
FIG. 11a is a perspective view of a switchgear in accordance with an embodiment of the present disclosure;
FIG. 11b is a side view of the switchgear as shown in FIG. 11a;
FIG. 11c is a schematic view of the switchgear as shown in FIG. 11b with the door of the switchgear being removed ;
FIG. 11d is a partial enlarged view of the portion A as shown in FIG. 11c; and
FIG. 11e is a partial enlarged view of the portion B as shown in FIG. 11a.
Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.
DETAILED DESCRIPTION OF EMBODIEMTNS
Principles of the present disclosure will now be described with reference to several example embodiments shown in the drawings. Though example embodiments of the present disclosure are illustrated in the drawings, it is to be understood that the embodiments are described only to facilitate those skilled in the art to better understand and thereby implement the present disclosure, rather than to limit the scope of the disclosure in any manner.
The term “comprises” or “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “or” is to be read as “and/or” unless the context clearly indicates otherwise. The term “based on” is to be read as “based at least in part on. ” The term “being operable to” is to mean a function, an action, a motion or a state that can be achieved by an operation induced by a user or an external mechanism. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.
According to embodiments of the present disclosure, a locking device is provided. The locking device comprises a holder, bolt, a movable plate and an elastic resetting element. The bolt is supported by the holder and movable with respect to the holder. The bolt comprises a groove extending along the length direction of the bolt and a bolt head adapted to move outside of the holder and retract back into the holder. The movable plate is partially arranged in the groove and is movable with respect to the bolt. The movable plate comprises a first inclined part adapted to interact with an end of the groove when the movable plate is pushed towards the holder, such that the bolt moves with respect to the holder. The above idea may be implemented in various manners, as will be described in detail in the following paragraphs.
Hereinafter, the principles of the present disclosure will be described in detail with reference to FIGS. 1-11e. Referring to FIGS. 1-4 first, FIG. 1 is a perspective view of a locking device in accordance with an embodiment of the present disclosure, FIG. 2 is a side view of the locking device as shown in FIG. 1, FIG. 3 is a bottom view of the locking device as shown in FIG. 1, and FIG. 4 is a top view of the locking device as shown in FIG. 1. As shown in FIGS. 1-4, the locking device 10 described herein generally includes a holder 102, a bolt 104, a movable plate 106 and an elastic resetting element 108. The bolt 104 is supported by the holder 102 and is movable with respect to the holder 102 along a length direction X of the bolt 104. The bolt 104 includes a groove 120 extending along the length direction X of the bolt 104 and a bolt head 109 adapted to move outside of the holder 102 and retract back into the holder 102. The movable plate 106 is partially arranged in the groove 120 and is movable with respect to the bolt 104 along a vertical direction Y normal to the length direction X of the bolt 104. The movable plate 106 includes a first inclined part 113 adapted to interact with an end of the groove 120 when the movable plate 106 is pushed towards the holder 102, such that the bolt 104 moves with respect to the holder 102 along the length direction X of the bolt 104 and the bolt head 109 retracts back into the holder 102. The elastic resetting element 108 is arranged on the bolt 104 and configured to reset the bolt 104 when the movable plate 106 is released such that the bolt head 109 moves outside of the holder 102.
With the arrangement of the locking device 10, the position of the bolt head 109 of the bolt 104 can be controlled. Specifically, when the movable plate 106 is pushed towards the holder 102, the first inclined part 113 would press the end of the groove 120, such that the bolt 104 moves towards the left with respect to the holder 102 along the length direction X of the bolt 104 and the bolt head 109 retracts back into the holder 102. Likewise, when the movable plate 106 is released and moves away from the holder 102, the bolt 104 would move towards the right with respect to the holder 102 along the length direction X of the bolt 104 and the bolt head 109 of the bolt 104 would move outside of the holder 102.
The locking device 10 can be installed at a proper position on an apparatus, such as on a door of a switchgear. The locking device 10 can be configured to interact with a front seal plate of a circuit breaker in the switchgear. When the circuit breaker is in the working position, the front seal plate of the circuit breaker is far away from the movable plate 106, and thus the bolt head 109 of the bolt 104 moves outside of the holder 102 so as to be inserted into a hole in a door frame of the switchgear. In this case, the door would be locked. When the circuit breaker switches from the working position to the test position, the front seal plate of the circuit breaker would push the movable plate 106 of the locking device 10, and thus the bolt head 109 of the bolt 104 would retract back into the holder 102. In this case, the door would be unlocked. With the above arrangement, the locking device 10 can prevent an operator from entering the live space of the switchgear by mistake in a manner that is simple, low cost, and user friendly. It is to be understood that the locking device 10 according to embodiments of the present disclosure may be used in other mechanical or electrical devices. The scope of the present disclosure is not intended to be limited in this respect.
Example constructions of the bolt 104 will be further described with reference to FIGS. 1-4 and 9a-9d. FIG. 9a is a perspective view of a bolt in accordance with an embodiment of the present disclosure, FIG. 9b is a bottom view of the bolt as shown in FIG. 9a, FIG. 9c is a side view of the bolt as shown in FIG. 9a, and FIG. 9d is a cross sectional view of the bolt as shown in FIG. 9a In some embodiments, as shown in FIGS. 1-4 and 9a-9d, the bolt 104 includes a first portion 105 and a second portion 107 extending along the length direction X of the bolt 104. The second portion 107 is connected to the first portion 105. The diameter of the first portion 105 is smaller than that of the second portion 107. The bolt head 109 is arranged at an end of the second portion 107 opposite to the first portion 105. The elastic resetting element 108 includes a spring arranged around the first portion 105. A first end of the spring is against a first side of the holder 102, and a second end of the spring is against the second portion 107.
In some embodiments, as shown in FIGS. 1-4, and 9a-9d, the first portion 105 has a smaller diameter than that of the second portion 107. However, it is to be understood that such a diameter relationship is only an example of the first portion 105 and the second portion 107. In other embodiments, the first portion 105 and the second portion 107 may have the same diameter. Some positioning elements, such as positioning pins, retaining ring and the like may be arranged on the surface of the bolt 104, and coupled to the second end of the spring. With such an arrangement, it is unnecessary to provide a bolt with different diameters, and thus the manufacturing process of the bolt 104 may be simplified. The scope of the present disclosure is not intended to be limited in this respect.
In some embodiments, as shown in FIG. 9a, the groove 120 is arranged at the second portion 107. In some embodiments, as shown in FIG. 9c, the groove 120 includes a second inclined part 111. The second inclined part 111 is arranged at an end of the groove 120 away from the bolt head 109. The second inclined part 111 is adapted to engage with the first inclined part 113. The inclination angle of the second inclined part 111 is substantially equal to that of the first inclined part 113. As shown in FIG. 9d, the groove 120 of the bolt 104 extends through the bolt 104 radially. In some embodiments, the bolt head 109 is not limited to the shape as shown in FIGS. 9a and 9c-9d, but may be of other shapes, such as elliptical shape, spherical shape, conical shape, etc. The scope of the present disclosure is not intended to be limited in this respect.
With the above arrangement, when the movable plate 106 is pushed towards the holder 102, the spring may be compressed by the first side of the holder 102 and the second portion 107 (for example, by a shoulder 137 of the second portion 107) . When the movable plate 106 is released, that is, when the movable plate 106 moves upward, the bolt 104 will be pushed by the spring and move right along the length direction X of the bolt 104. Thus the bolt head 109 will move outside of a second side of the holder 102 opposite to the first side for a predetermined distance. If the locking device 104 is installed on the door of the switchgear, the bolt head 109 will be inserted into a hole in the switchgear.
In some embodiments, as shown in FIGS. 1-4, the groove 120 of the bolt 104 is arranged in the second portion 107 of the bolt 104 and extends into the bolt head 109. However, it is to be understood that such a structure is only an example of the groove 120. In other embodiments, the groove 120 of the bolt 104 may not extend into the bolt head 109. The size of both the groove 120 and the bolt head 109 may be varied as needed. The scope of the present disclosure is not intended to be limited in this respect.
In some embodiments, as shown in FIGS. 1-4, the holder 102 includes a first holding portion 128 and a second holding portion 130. The first holding portion 128 is provided with a first hole 132 and the second holding portion 130 is provided with a second hole 136. The first holding portion 128 and the second holding portion 130 are arranged opposite to each other. The bolt 104 extends through the first hole 132 and the second hole 136. Specifically, the first portion 105 of the bolt 104 extends through the first hole 132 and the second portion 107 of the bolt 104 extends through the second hole 136.
In some embodiments, as shown in FIGS. 1-4, the holder 102 further includes a bottom portion 126 arranged between the first holding portion 128 and the second holding portion 130. The holder 102 is generally of a U-shape. In other embodiments, the holder 102 may be of other shapes, such as H-shape, etc. In some embodiments, the holder 102 is formed of a plate. However, it is to be understood that such a structure is only an example of the holder 102. In some embodiments, the holder 102 may be formed of poles. In other embodiments, the holder 102 may have other configurations. The scope of the present disclosure is not intended to be limited in this respect.
In some embodiments, as shown in FIGS. 1-4, the bottom portion 126 is provided with fixing holes 114 for fixing the holder 102 onto a plane structure. For example, the locking device 104 may be fixed onto the door by screw bolts passing through the fixing holes 114. In some embodiments, as shown in FIG. 1, four fixing holes 114 are provided on the first bottom plate 126. In other embodiments, other numbers of fixing holes 114 may be provided. For example, two, three or more fixing holes 114 may be provided.
Example constructions of the movable plate 106 will be further described with reference to FIGS. 1-4 and FIGS. 8a and 8b. FIG. 8a is a perspective view of a movable plate in accordance with an embodiment of the present disclosure, and FIG. 8b is a side view of the movable plate as shown in FIG. 8a. In some embodiments, as shown in FIGS. 1-4 and FIGS. 8a and 8b, the movable plate 106 includes a first movable portion 116 and a second movable portion 118 connected to the first movable portion 116. The first inclined part 113 is arranged at a first side of the first movable portion 116. The inclination angle of the first inclined part 113 may be varied, preferably in the range of 30° to 60° with respect to the length direction X of the bolt 104. With such an arrangement, the ratio between the moving distance of the bolt 104 and the moving distance of the movable plate 106 can be controlled in a proper range.
In some embodiments, the second movable portion 118 extends along the vertical direction Y and passes through the groove 120. However, it is to be understood that such a structure is only an example of a second movable portion 118. In other embodiments, the second movable portion 118 may not extend along the vertical direction Y. The scope of the present disclosure is not intended to be limited in this respect.
In some embodiments, as shown in FIGS. 1-4 and FIGS. 8a and 8b, the movable plate 106 is provided with an unlocking hole 110. The unlocking hole 110 is arranged at an end of the second movable portion 118 opposite to the first movable portion 116. The unlocking hole 110 is adapted to be pulled such that the bolt head 109 retracts back into the holder 102. The unlocking hole 110 can be used to unlock the locking device 10 in a case that the door equipped with the locking device 10 is locked by mistake. For example, in some embodiments, the locking device 10 is installed on an inner side of the door, and the unlocking hole 110 is exposed outside of the door. With such an arrangement, by pulling the unlocking hole 110, the movable plate 106 can move toward the bottom portion 126 of the holder 102. Then, the bolt 104 would move towards the first holding portion 128 of the holder 102 and press the spring. Accordingly, the bolt head 109 will retract back into the holder 102, thereby unlocking the door. In this way, a convenient approach is provided to unlock the door in case of emergency.
In some embodiments, as shown in FIGS. 1-4 and FIGS. 8a-8b, the movable plate 106 is provided with a stop pin 112. The stop pin 112 is arranged on the second movable portion 118 and adapted to limit the moving range of the movable plate 106 with respect to the bolt 104 along the vertical direction Y. In other embodiments, the stop pin 112 may be arranged on the first movable portion 116. The scope of the present disclosure is not intended to be limited in this respect. In some embodiments, as shown in FIGS. 1 and 2, when the stop pin 112 is close to the bolt 104, the bolt head 109 moves outside of the holder 102 for a predetermined distance. When the stop pin 112 is away from the bolt 104, the bolt head 109 retracts back into the holder 102. The movement of the bolt head 109 will be further described in detail with reference to FIGS. 5 -7.
FIG. 5 is a bottom view of the locking device in accordance with an embodiment of the present disclosure, FIG. 6 is a side view of the locking device as shown in FIG. 5, and FIG. 7 is a top view of the locking device as shown in FIG. 5. In some embodiments, as shown in FIG. 6, the stop pin 112 is away from the bolt 104 and contacts the bottom portion 126 of the holder 102. The bolt 104 is pushed by the movable plate 106, such that the bolt 104 moves towards the left and the spring is compressed. In some embodiments, as shown in FIGS. 5-7, the bolt head 109 retracts back into the holder 102, and the first portion 105 of the bolt 104 extends beyond the first side of the holder 102 for a predetermined distance.
With such an arrangement, the movable plate 106 will be limited in a predetermined moving range. In this way, the stop pin 112 can prevent the movable plate 106 from being separated from the locking device 10, and can prevent the bolt head 109 from being separated from the second hole 136 due to excessive pressure from the movable plate 106.
The locking device 10 may be implemented in various configurations in accordance with embodiments of the present disclosure. Example configurations of the locking device 10 will be further described in detail hereinafter with reference to FIGS. 3-9d.
In some embodiments, as shown in FIG. 3, the holder 102 is provided with a second groove 122. The second movable portion 118 of the movable plate 106 extends through the second groove 122. It is to be understood that the second movable portion 118 of the movable plate 106 and the second groove 122 may be arranged in other manners. The scope of the present disclosure is not intended to be limited in this respect.
It is to be understood that the locking device 10 is not limited to the configuration as described above, but may be of any other configuration without deviating from the scope of the present disclosure.
A switchgear equipped with the locking device 10 will be described in detail with reference to FIGS. 10a-10e.
FIG. 10a is a perspective view of a switchgear in accordance with an embodiment of the present disclosure. In some embodiments, the locking device 10 is installed in an inner side of the switchgear 100, as shown in portion B of FIG 10a. Under normal conditions, for the sake of personnel safety, the door 20 of the switchgear 100 is closed. The operation position and test position of the circuit breaker can be switched by rotating a screw rod by means of a crank. The door 20 is normally opened only in the test position. However, as mentioned above, there is a possibility that an operator may enter the live space of the switchgear 100 by mistake if no locking device is provided in the switchgear 100. The switchgear 100 in accordance with an embodiment of the present disclosure will be capable of preventing someone from entering the live space of the switchgear 100 by mistake.
FIG. 10b is a side view of the switchgear as shown in FIG. 10a, FIG. 10c is a schematic view of the switchgear as shown in FIG. 10b with a door of the switchgear being removed, FIG. 10d is a cross sectional view of the portion A as shown in FIG. 10c, and FIG. 10e is a partial enlarged view of the portion B as shown in FIG. 10a.
In some embodiments, as shown in the portion A of FIG. 10c, the locking device 10 is installed on an inner side and close to the door frame of the door 20 of the switchgear 100. In other embodiments, the locking device 10 may be arranged at other positions with respect to the door 20.
The installation of the locking device 10 on the switchgear 100 is simple, and a few changes need to be made to the switchgear 100. Firstly, the locking device 10 can be fixed on the door 20 of the switchgear 100 through a bracket. Secondly, the hole can be opened in a corresponding position of the switchgear frame to match with the bolt head 109. Thus, it is convenient to install the locking device 10 on site.
In some embodiments, as shown in FIG. 10d and 10e, a front seal plate 202 of the circuit breaker in the switchgear 100 contacts and presses a side of the movable plate 106. The movable plate 106 pushes the bolt 104 to move towards the left. An end of the first portion 105 of the bolt 104 moves outside of the holder 102. The stop pin 112 is against the bottom portion 126 of the holder 102. The bolt head 109 retracts back into the holder 102. Thus the door 20 is unlocked. In this state, the door 20 can be opened and closed freely.
In some embodiments, as shown in FIG. 10d and 10e, there is a hole 119 on the door 20. The second portion 118 of the movable plate 106 is located close to the hole 119. The second portion 118 of the movable plate 106 may be pulled via a tool inserted into the unlocking hole 110 in case that the door 20 of the switchgear 100 equipped with the locking device 10 is locked by mistake. In some embodiments, the second movable portion 118 is adapted to be pulled out through the unlocking hole 110. That is, the door 20 can be unlocked by pulling the unlocking hole 110. With such an arrangement, even if the door 20 is locked by mistake, the operator can also unlock it.
FIG. 11a is a perspective view of a switchgear in accordance with an embodiment of the present disclosure, FIG. 11b is a side view of the switchgear as shown in FIG. 11a, FIG. 11c is a schematic view of the switchgear as shown in FIG. 11b with the door of the switchgear being removed, FIG. 11d is a partial enlarged view of the portion A as shown in FIG. 11c, and FIG. 11e is a partial enlarged view of the portion B as shown in FIG. 11a . In some embodiments, as shown in FIG. 11a-11e, the locking device 10 is installed in the inner side of the door 20 of the switchgear. A front seal plate 202 of the circuit breaker in the switchgear 100 is far away from the movable plate 106, such that the movable plate 106 is released. The stop pin 112 is against the bolt 104. The bolt head 109 moves outside of the holder 102 and is inserted into a door frame hole 129. Thus, the door 20 is locked.
In some embodiments, as shown in FIGS. 1 to 11e, a locking device 10 is provided to retrofit the original switchgear on a customer site or to be installed along with a new switchgear. The main functions of the locking device 10 include:
a) When the circuit breaker is moving (leaving the test position) , the door cannot be opened;
b) When the circuit breaker is in the working position, the door cannot be opened;
c) When the circuit breaker is in the test position, the door can be opened and closed freely.
The locking device 10 of the present disclosure is easier and more convenient to be installed in customers’ original switchgear, which can prevent an operator from entering the live space of the switchgear by mistake, and can well meet requirements of the customers for upgrading the switchgear.
It is to be understood that the locking device 10 can be used not only in the switchgear, but also in other apparatuses which need the interlocking function.
It is to be understood that the locking device 10 and the switchgear 100 are not limited to the configuration as described above, but may be of any other configuration. The scope of the present disclosure is not intended to be limited in this respect.
While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

Claims

A locking device (10) comprising:

a holder (102) ;

a bolt (104) supported by the holder (102) and being movable with respect to the holder (102) along a length direction (X) of the bolt (104) , the bolt (104) comprising a groove (120) extending along the length direction (X) of the bolt (104) and a bolt head (109) adapted to move outside of the holder (102) and retract back into the holder (102) ;

a movable plate (106) partially arranged in the groove (120) and being movable with respect to the bolt (104) along a vertical direction (Y) normal to the length direction (X) of the bolt (104) , the movable plate (106) comprising a first inclined part (113) adapted to interact with an end of the groove (120) when the movable plate (106) is pushed towards the holder (102) , such that the bolt (104) moves with respect to the holder (102) along the length direction (X) of the bolt (104) and the bolt head (109) retracts back into the holder (102) ; and

an elastic resetting element (108) arranged on the bolt (104) and configured to reset the bolt (104) when the movable plate (106) is released such that the bolt head (109) moves outside of the holder (102) .
The locking device according to claim 1, wherein the bolt (104) comprises a first portion (105) and a second portion (107) extending along the length direction (X) of the bolt (104) and connected to each other, the diameter of the first portion (105) is smaller than that of the second portion (107) , and the elastic resetting element (108) comprises a spring arranged around the first portion (105) , a first end of the spring is against a first side of the holder (102) , and a second end of the spring is against the second portion (107) .
The locking device according to claim 2, wherein the bolt head (109) is arranged on the second portion (107) of the bolt (104) and adapted to move outside of a second side of the holder (102) opposite to the first side for a predetermined distance when the movable plate (106) is released.
The locking device according to claim 3, wherein the groove (120) of the bolt (104) is arranged in the second portion (107) of the bolt (104) and extends into the bolt head (109) , and the groove (120) comprises a second inclined part (111) arranged at an end of the groove (120) away from the bolt head (109) and adapted to engage with the first inclined part (113) .
The locking device according to claim 4, wherein the inclination angle of the second inclined part (111) is substantially equal to that of the first inclined part (113) .
The locking device according to claim 1, wherein the holder (102) comprises a first holding portion (128) provided with a first hole (132) and a second holding portion (130) provided with a second hole (136) , the first holding portion (128) and the second holding portion (130) are arranged opposite to each other, and the bolt (104) extends through the first hole (132) and the second hole (136) .
The locking device according to claim 6, wherein the holder (102) further comprises a bottom portion (126) arranged between the first holding portion (128) and the second holding portion (130) , and the holder (102) is generally of a U-shape.
The locking device according to claim 7, wherein the bottom portion (126) is provided with fixing holes (114) for fixing the holder (102) onto a plane structure.
The locking device according to claim 1, wherein the movable plate (106) comprises a first movable portion (116) and a second movable portion (118) connected to the first movable portion (116) ,

the first inclined part (113) is arranged at a first side of the first movable portion (116) .
The locking device according to claim 9, wherein the movable plate (106) is provided with an unlocking hole (110) arranged at an end of the second movable portion (118) opposite to the first movable portion (116) and adapted to be pulled such that the bolt head (109) retracts back into the holder (102) .
The locking device according to claim 9, wherein the movable plate (106) is provided with a stop pin (112) arranged on the second movable portion (118) and adapted to limit the moving range of the movable plate (106) with respect to the bolt (104) along the vertical direction (Y) .
The locking device according to claim 11, wherein when the stop pin (112) is close to the bolt (104) , the bolt head (109) moves outside of the holder (102) for a predetermined distance, and when the stop pin (112) is away from the bolt (104) , the bolt head (109) retracts back into the holder (102) .
The locking device according to claim 9, wherein the holder (102) is provided with a second groove (122) through which the second movable portion (118) of the movable plate (106) extends.
A switchgear comprising the locking device according to any one of claims 1-13, wherein the locking device is arranged on a door of the switchgear.