AU2012311345B2 - Electrical line protection device provided with means of indicating an electrical fault on the line - Google Patents

Abstract

An electrical line protection device of the circuit-breaker type (1) characterised in that it comprises indicator means indicating the occurrence of an electrical fault and storing this information until the handle (3) is reset in the ON position, said indicator means consisting of a portion of said cam (11) which is visible through a window (4) formed in the drum (7) in the OFF position of the handle (3) following an electrical fault, and is not visible in the ON/OFF positions of the handle (3) following a manual action.

Description

1 ELECTRICAL LINE PROTECTION DEVICE PROVIDED WITH MEANS OF INDICATING AN ELECTRICAL FAULT ON THE LINE The present invention relates to the signaling of an electrical fault on 5 an electrical line protection device of the circuit breaker type provided with a snap closing mechanism for the contacts. This type of device will be described later. The invention essentially pertains to an indicator means that signals a fault and must additionally store the information until the device is reset. More 10 specifically, the invention consists of indicating to a user whether the device in question has been turned on manually or has been turned on following an electrical fault on the line, whether it involves an overload or a short circuit. For improved safety, the signaling system according to the invention is mechanical, and not electrical and dependent on a power source of the 15 electrical installation that the circuit breaker is protecting in order to operate. Many mechanical signaling systems exist, but are systematically adapted to devices different from that of the invention. In fact, the internal activation mechanisms differ from one device to another based on their function, form, number of poles, etc. 20 The aim of the present invention therefore consists of establishing a fault indicator within the device as described below, without causing a significant modification in the mechanism of the device. The placement of this indicator inside the device must be easy and must be easily inserted into the current manufacturing process for the product. Furthermore, the solution 25 must be economically advantageous. The type of device in question comprises at least one moving contact provided to cooperate with at least one stationary contact, the moving contact being pivotably positioned relative to a contact-holder of a mechanical lock, the relative positioning when idle being ensured by the action of a so-called 30 contact spring making it possible to guarantee correct pressure when the contacts are closed. This contact-holder is in turn driven in a rotational movement making it possible to position the moving contact alternately against and away from the stationary contact, in particular by manual action on a control handle pivoting between two stable positions (ON position 2 closing the contacts and OFF position opening the contacts), and driving the rotation of the contact-holder through a traditional toggle lever mechanical system. The contact-holder may also be rotated following a mechanical action 5 of an actuator reflecting an electrical fault on the line. In that case, the contact-holder first positions the moving contact away from the stationary contact, and secondly rotates the control lever toward the OFF position. Such a snap closing mechanism, for example disclosed in patent EP 1,170,769, primarily includes two members pivoting with the control lever and 10 the moving contact, respectively, with trajectories that interfere during a fraction of their combined rotation. These members are provided to cooperate with the aim of locking the moving contact away from the stationary contact during said rotation fraction, before abruptly releasing at the end of the cooperation phase, and subsequent closing of the contacts at 15 a speed independent of the speed exerted on the handle. The members according to the invention participating in the snap closing function are made up of a cam driven by the control handle, in which it is positioned rotating freely over an angular movement between two indexing positions, and a finger secured to the lock, the positioning of which 20 relative to the cam and the moving contact, respectively, is such that the finger and the cam come into contact when the stationary and moving contacts are separated by a predetermined residual distance, the cam having an outer surface along which the finger slides when the rotation of the handle continues, with a length and shape such that said finger remains locked in 25 rotation during a rotation fraction of the handle smaller than its residual travel to reach its stable position closing the contacts. The contact-holder continues its travel, while the contact spring accumulates energy, which it releases abruptly when the cam/finger contact ceases, in the final portion of the travel of the handle. The cam can then 30 continue its rotation relative to the handle. Concretely, the cam is: - in the second indexing position in the handle in the ON position; 3 - in the first indexing position in the handle in the OFF position following its catching with the finger of the lock during manual action on the handle; in the second indexing position in the handle in the OFF position 5 following switching of the lock driving the rotation of the handle in case of electrical fault. The invention essentially includes indicator means signaling the appearance of an electrical fault and storing that information until the handle is reset in the ON position. Said indicator means consist of a portion of said 10 cam that is visible through a window formed in the drum in the OFF position of the handle following an electrical fault, and not visible in the ON/OFF positions of the handle following a manual action. More specifically, said window of the drum is positioned radially across from said portion when the cam is in the second indexing position in the 15 handle in the OFF position following an electrical fault. According to the invention, the window is formed in the outer facade of the drum visible by a user when the handle is in the OFF position. Preferably, the surface of the cam portion visible from the outside through the window bears a mark signaling a fault. 20 According to one possible configuration, said mark signaling a fault may consist of a color or surface condition different from the color or surface condition of the inner walls of the drum. For example, the portion may be colored red, whereas the drum is normally gray like the housing of the circuit breaker. 25 Any other type of mark may, however, be considered in the context of this invention. According to a first possibility, said portion of the cam constituting the indicator means consists of an angular sector of the cam. According to another possibility, the portion of the cam constituting the 30 indicator means consists of a tab secured to said cam rotating inside the drum of the handle. In one particularly preferred embodiment, the cam includes: - a hollow cylindrical barrel rotating around a central journal equipping the center of the drum of the handle; 4 - a radial protuberance extending from said drum and including a free end constituting a protruding angular sector cooperating with the finger of the lock; - an elastic element consisting of a tongue fastened to the outer 5 surface of the barrel and developing substantially parallel to the barrel while gradually moving away toward its free end, the latter being oriented toward the radial protuberance and placed on the side of the protuberance first coming into contact with said finger during closing of the contacts; 10 - said fault indicating portion located at the outer surface of the barrel and situated substantially across from the tongue relative to the central axis of symmetry of the barrel. The drum of the handle includes an opening positioned substantially opposite the lever and allowing the passage of the radial protuberance and 15 the free end of the tongue, the radial edges of the openings delimiting the angular space where the cam is freely rotating. According to one possible indexing configuration, these radial edges constitute stops between which the cam rotates freely, the cam being in the first (second, respectively) indexing position in contact with the stop. 20 Concretely, when the cam rotates in the drum, the free end of the tongue is capable of coming into contact with one of the stops of the opening of the drum, while the edge of the protuberance not across from the tongue is capable of coming into contact with the other stop of the opening of the drum during reverse rotation. 25 Thus, the fault indicating portion is situated across from the window when the free end of the tongue is in contact with one of the stops in the OFF position of the handle following an electrical fault. Furthermore, a lug protruding from the tongue also cooperates with the stop so as to keep the cam in the second indexing position during 30 automatic opening following a fault. More specifically, said lug is then situated at an end ramp of the stop when the protuberance is in contact with the stop, or in contact with an inner wall of the drum of the handle when the free end of the tongue comes into contact with said ramp.

5 In fact, each indexing position is then characterized by the existence of a rotational stop and maintaining means in said stop, which consists of the ramp-lug cooperation on one hand and the lug-inner wall of the drum friction on the other hand. 5 According to another possible configuration, the indexing may be done via the fault indicating portion, when the latter corresponds to a tab. To that end, the inner wall of the handle is provided with a spur protruding in the vicinity of the window and capable of being inserted into one of the two notches formed in the inner surface of the fault indicating tab, the cam being 10 in the first or second indexing position depending on the notch in which the spur is housed. Thus, the fault indicating tab is situated across from the window when the spur is housed in the proximal notch of the radial protuberance of the cam in the OFF position of the handle following an electrical fault. 15 The invention will now be described in more detail, in reference to the appended figures, in which: - figure 1a shows a circuit breaker that has been triggered manually; - figure 1 b shows a circuit breaker that has been triggered following an electrical fault; 20 - figure 2 is a perspective view of a control handle according to the invention; - figure 3 illustrates a cam according to the invention; - figures 4a to 4c show a manual opening cycle not causing any fault indication; 25 - figures 5a to 5c show an automatic opening cycle leading to signaling of an electrical fault; - figures 6a to 6d illustrate a closing cycle of the contacts followed by manual opening; - figures 7a to 7c show a closing cycle of the contacts following 30 automatic opening; - figures 8a and 8b illustrate another drum and cam configuration according to the invention. In reference to figures la and 1b, the circuit breaker (1) includes a plastic molded housing (2) from which a control handle (3) protrudes whereof 6 the two stable ON and OFF positions correspond to the closing and opening of the contacts, respectively. The handle (3) is in the OFF position in figures 1a and 1b. A window (4) situated below the lever (5) of the handle (3) cooperates 5 with the signaling means according to the invention. More specifically, in figure la, the signaling means are not visible through the window (4), meaning that the circuit breaker (1) has been triggered following a manual action on the control handle (3). On the contrary, in figure 1 b, a color signal (6) appears through the window (4), indicating that the circuit breaker (1) was 10 triggered following an electrical fault on the line. The window (4) is formed in the handle (3) and is clearly shown on the front face of the circuit breaker (1). As illustrated in figure 2, the handle (3) is primarily made up of the drum (7) and the control lever (5) extending radially from the drum (7). The 15 latter is made up of two coaxial walls, i.e., an inner wall (9) and an outer wall (8). The window (4) is formed in said outer wall (8), and situated below the lever (5). A central journal (10) equips the center of the drum (7) delimited by the inner wall (9). In reference to figure 3, the cam (11) includes a hollow cylindrical 20 barrel (12) capable of rotating around the central journal (10) of the drum (7). A radial protuberance (13) extends from the barrel (12) and has a free end (14) constituting a relatively large protruding angular sector coaxial to the cylindrical surface of the barrel (12). An elastic element consisting of a tongue (15) is fastened to the outer 25 surface of the barrel (12). This tongue (15) develops substantially parallel to the barrel (12), while nevertheless gradually moving away from it toward its free end (16), the latter being oriented toward the radial protuberance (13). A lug (27) protrudes from the tongue (15) in the vicinity of its middle. A fault indicating tab (17) is fastened to the outer surface of the barrel 30 (12) and situated substantially opposite the tongue (15) relative to the central axis of symmetry of the barrel (12). The outer surface (6) of the tab (17) is preferably colored red, which is the symbolic color for a fault signal. Concretely, this tab (17) is capable of circulating inside the hollow space defined between the two walls (8, 9) of the drum (7) when the cam 7 (11) pivots around the journal (10). Depending on its position, the tab (17) is visible through the window (4), or hidden beneath the outer wall (8) of the drum (7). For the cam (11) to be able to pivot around the journal (10), an 5 opening (18) is formed in the walls (8, 9) of the drum (7). This opening (18) is positioned substantially opposite the lever (5) and allows the passage of the radial protuberance (13) and the free end (16) of the tongue (15), the radial edges (19, 20) of the opening (18) constituting the stops between which the cam (11) freely rotates. 10 In practice, as shown in figures 4a to 7c, during the rotation of the cam (11) in the drum (7), the free end (16) of the tongue (15) is capable of coming into contact with one (20) of the opening stops (18) of the drum (7), the cam (11) then being in the first indexing position in the handle (3), while the edge of the protuberance (13) not facing the tongue (15) is capable of coming into 15 contact with the other stop (19) of the opening (18) of the drum (7), the cam (11) then being back in the second indexing position in the handle (3). Figures 4a to 7c all show relative positions of the cam (11) and a fortiori of the tab (17), relative to the drum (7) during opening and closing phases of the contacts. 20 In general, the control mechanism of the circuit breaker (1) consists of a handle (3) (as previously described) connected to a contact-holder (21) by a connecting rod (22). This is therefore a traditional toggle lever lock system allowing switching of the contact-holder (21) following pivoting of the handle (3) via a manual action on the lever (5). The contact-holder (21) also bears a 25 trigger (31) capable of switching it if an electrical fault is detected on the line. A torsion spring (not shown) is placed between the moving contact (23) and the contact-holder (21). This spring makes it possible to store energy to produce abrupt closing of the contacts when the moving contacts are immobilized by the snap closing mechanism, then to maintain the 30 pressure between the stationary (24) and moving (23) contacts. A finger (25) secured to the contact-holder (21) extends toward the outside thereof, toward the protuberance (13) of the cam (11) plugged into the control handle (3). The free end (26) of the finger (25) is provided to 8 cooperate with the outer surface (14) of the protuberance (13) of the cam (11). In fact, the finger (25) and the protuberance (13) have trajectories that interfere during manual opening of the contacts as illustrated in figures 4a to 5 4d. In figure 4a, the contacts are closed, the handle (3) is in the ON position, and the protuberance (13) of the cam (11) is in contact with the stop (19) in the drum (7), the cam (11) being in the second indexing position. If the control handle (3) is actuated manually in the clockwise direction, the cam 10 (11) follows the rotational movement until the free end (14) of the protuberance (13) comes into contact with the finger (25) of the contact holder (see figure 4b), thereby immobilizing the cam (11) during the fraction of the rotation of the handle (3), until the tongue (15) of the cam (11) comes into contact with the stop (20) in the drum (7) (see figure 4c). During that 15 movement, the tongue (15) is then slightly deformed toward the barrel (12), the lug (27) moving in contact with the stop (20), which consists of a tab whereof the free end constitutes a ramp, until coming into frictional contact on the coaxial inner wall (9) of the handle (3). The cam (11) therefore changes position relative to the inside of the handle (3), between figure 4b 20 and figure 4c, and goes from the second to the first indexing position owing to the flexibility of the tongue (15) combined with the locations of the different stops (19, 20). The handle (3) ends its residual travel to reach its OFF position, rotating the cam (11) with it on the one hand, and causing the contact-holder (21) to switch via the toggle lever mechanism on the other 25 hand, thereby separating the finger (25) from the protuberance (13) and the moving contact (23) from the stationary contact (24). Figure 4d shows the final open state of the contacts. The handle (3) being in the OFF position, the window (4) is visible from outside the circuit breaker (1). The cam (11) being in the first indexing position in the handle (3), the signaling tab (17) is hidden 30 behind the outer wall (8) of the drum (7), and not situated across from the window (4). There is therefore no fault indication, the opening of the contacts having been caused by a manual action on the control handle (3). Figures 5a to 5c show the case of automatic opening of the contacts. Figure 5a is identical to figure 4a, since it involves the same starting position.

9 Figure 5b differs from figure 4b in that the handle (3) is not manipulated, but the contact-holder (21) has switched via an action of the actuator (magnetic or thermal) on the trigger (31) following the detection of a fault, immediately driving switching of the toggle lever and opening of the contacts. Owing to 5 the release of the connecting rod (22), the rotation of the contact-holder (21) / trigger (31) assembly is independent of the rotation of the handle, and is done quickly-under the effect of specific return means-in a first step. The handle (3) and the connecting rod (22) are then secondly brought into the OFF position, corresponding to figure 5c, by means of a return spring of the 10 handle (3). During this opening of the contacts, the finger (25) and the protuberance (13) do not collide, and the cam (11) remains pressed against the stop (19) during pivoting of the handle (3), in particular owing to the lug (27) that is in contact with the end of the end ramp of the stop (20) so as to keep the cam (11) in its second indexing position in the handle (3). In the 15 OFF position, the window (4) is therefore visible from the outside of the circuit breaker (1), and the tab (17) is situated across from the window (4) this time. The red outer surface (6) of the tab (17) is therefore clearly visible by a user, and indicates triggering of the circuit breaker following an electrical fault. Figures 6a to 6d show the resetting of the circuit breaker (1) following 20 manual opening of the contacts. In figure 6a, which is identical to figure 4d, the handle (3) is shown in its OFF position following manual opening, with the cam (11) in the first indexing position, and the signaling tab (17) not visible through the window (4). In this position, the finger (25) is situated away from the protuberance 25 (13) of the cam (11). When the handle (3) is actuated in the direction closing the contacts, as shown in figure 6b, i.e., when it is rotated in the counterclockwise direction, the moving contact (23) is rotated by the contact-holder (21) in the clockwise direction. In that case, the finger (25) and the protuberance (13) of 30 the cam (11) progress toward one another, substantially in the same direction, until their free ends (26, 14) meet. This collision causes the movement of the finger (25) to stop on the one hand, and the rotation of the cam (11) to stop on the other hand, while the handle (3) continues its rotation. The cam (11) is once again rotated by the handle (3) once the stop 10 (19) of the drum (7) comes into contact with the protuberance (13) of the cam (11), as shown in figure 6c. The cam (11) has therefore gone from the first to the second indexing position in the handle (3). While the finger (25) is still stopped by the upper surface (14) of the 5 protuberance (13), relative sliding occurs between the two (25, 13) when the cam (11) continues its rotation. Thus, although the rotation of the control handle (3) has progressed, the moving contact (23) has remained immobile, and at the same distance from the stationary contact (24). When the finger (25) ceases to be in contact with the outer surface 10 (14) of the protuberance (13), a sudden release occurs, as there is no longer anything opposing the continued rotation of the moving contact (23), owing to the energy stored by the torsion spring inserted between said contact (23) and contact-holder (21). The protuberance (13) is thus sent back away from the free end (26) of the finger (25) and the contacts (24, 23) close abruptly. 15 Figure 6d thus illustrates the ON position of the handle (3) with the contacts closed and the cam (11) in the second indexing position in the handle (3). Figures 7a to 7c show the different phases of resetting the circuit breaker (1) following automatic opening of the contacts (23, 24) caused by an electrical fault. The closing cycle of the contacts is practically identical to that 20 previously described. The main difference with resetting following manual opening lies in the initial position of the cam (11) in the handle (3), which is already in the second indexing position. Consequently, when the finger (25) collides with the protuberance (13), the cam (11) is not immobilized, but continues its rotation led by the handle (3), and relative sliding occurs 25 between the finger (25) and the protuberance (13). The abrupt closing takes place in the same way. The final position of the cam (11) in the handle (3) after closing of the contact is still identical, and is shown in figures 4a, 5a, 6d and 7c. In this position, the handle (3) is in the ON position and the window (4) is not visible by the user. 30 Figures 8a and 8b illustrate another indexing solution of the cam (11) within the handle (3). In this configuration, the rotation of the cam (11) is no longer limited by the radial edges (19, 20) of the opening (18) of the handle (3), but by the fitting of a spur (30) of the handle (3) in two notches (28, 29) of the cam (11). More specifically, the spur (30) protrudes from the inner coaxial 11 wall (9) of the drum (7) of the handle (3), in the vicinity of the window (4). Jointly, two notches (28, 29) are formed in the inner surface of the fault indexing tab (17) that is part of the cam (3). These two notches (28, 29) are distal with an arc corresponding to the angular movement of the cam (11) in 5 the handle (3) between its two indexing portions. Concretely, when the spur (30) is housed in the notch (29) ((28), respectively), the cam (11) is in its first (second, respectively) indexing position. The notches (28, 29) have beveled edges to facilitate the passage of 10 the spur (30) from one notch to the other. This passage is allowed by the force exerted by the finger (25) on the cam (11) during collisions. The invention has been described using one particular example configuration, in particular regarding the means for indicating a fault characterized by a tab (17) on the cam (11) and regarding the indexing 15 means of the cam (11) in the handle (3), which are, however, in no way limiting. The invention on the contrary encompasses all alternative embodiments and configurations that are within the reach of one skilled in the a rt.

Claims (15)

1. An electrical line protection device of the circuit breaker type provided including a handle for controlling at least one moving contact 5 movable between two stable positions, bearing on and away from a stationary contact, respectively, said handle being connected to the moving contact by means of a mechanical lock capable of switching while driving the opening of the contacts: - following a manual action on the lever of the handle, which pivots 10 between an ON position closing the contacts and an OFF position for opening the contacts; - following a mechanical action of an actuator reflecting an electrical fault on the line; a snap closing mechanism for the contacts being inserted between the 15 handle and the lock and including: - a cam driven by the handle and positioned freely rotating in the drum of the handle during an angular movement between two indexing positions - a finger secured to the lock and capable of coming into contact with 20 the cam until it is immobilized during a fraction of the rotation of the handle during manual closing/opening of the contacts, driving a change of position of the cam inside the handle; said cam being: - in the second indexing position in the handle in the ON position; 25 - in the first indexing position in the handle in the OFF position following its catching with the finger of the lock during manual action on the handle; - in the second indexing position in the handle in the OFF position following switching of the lock driving the rotation of the handle in 30 case of electrical fault; further including indicator means signaling the appearance of an electrical fault and storing that information until the handle is reset in the ON position, 2474480v1 13 said indicator means consisting of a portion of said cam that is visible through a window formed in the drum in the OFF position of the handle following an electrical fault, and not visible in the ON/OFF positions of the handle following a manual action. 5

2. The electrical line protection device of the circuit breaker type according to claim 1, wherein said window of the drum is positioned radially across from said portion when the cam is in the second indexing position in the handle in the OFF position following an electrical fault. 10

3. The electrical line protection device of the circuit breaker type according to any one of the preceding claims, wherein the window is formed in the outer facade of the drum visible by a user when the handle is in the OFF position. 15

4. The electrical line protection device of the circuit breaker type according to any one of the preceding claims, wherein the surface of the cam portion visible from the outside through the window bears a mark signaling a fault. 20

5. The electrical line protection device of the circuit breaker type according to any one of the preceding claims, wherein said mark signaling a fault may consist of a color or surface condition different from the color or surface condition of the inner walls of the drum. 25

6. The device according to any one of the preceding claims, wherein said portion of the cam constituting the indicator means consists of an angular sector of the cam. 30

7. The device according to any one of claims 1 to 5, wherein said portion of the cam constituting the indicator means consists of a tab secured to said cam rotating inside the drum of the handle. 2474480v1 14

8. The electrical line protection device of the circuit breaker type according to any one of the preceding claims, wherein the cam includes: - a hollow cylindrical barrel rotating around a central journal 5 equipping the center of the drum of the handle; - a radial protuberance extending from said drum and including a free end constituting a protruding angular sector cooperating with the finger of the lock; - an elastic element consisting of a tongue fastened to the outer 10 surface of the barrel and developing substantially parallel to the barrel while gradually moving away toward its free end, the latter being oriented toward the radial protuberance and placed on the side of the protuberance first coming into contact with said finger during closing of the contacts; 15 - said fault indicating portion located at the outer surface of the barrel and situated substantially across from the tongue relative to the central axis of symmetry of the barrel.

9. The electrical line protection device of the circuit breaker type 20 according to claim 8, wherein the drum of the handle includes an opening positioned substantially opposite the lever and allowing the passage of the radial protuberance and the free end of the tongue, the radial edges of the openings delimiting the angular space where the cam is freely rotating. 25

10. The electrical line protection device of the circuit breaker type according to claim 9, wherein the radial edges of the opening constitute stops between which the cam rotates freely, the cam being in the first (second, respectively) indexing position in contact with the stop, (respectively). 30

11. The electrical line protection device of the circuit breaker type according to claim 10, wherein when the cam rotates in the drum, the free 2474480v1 15 end of the tongue is capable of coming into contact with the stop of the opening of the drum, while the edge of the protuberance not across from the tongue is capable of coming into contact with the other stop of the opening of the drum. 5

12. The electrical line protection device of the circuit breaker type according to claim 11, wherein the fault indicating portion is situated across from the window when the free end of the tongue is in contact with the stop in the OFF position of the handle following an electrical fault. 10

13. The device according to any one of claims 8 to 12, wherein a lug protruding from the tongue also cooperates with the stop so as to keep the cam in the two indexing positions, said lug then being situated at an end ramp of the stop when the protuberance is in contact with the stop, or in 15 contact with an inner wall of the drum of the handle when the free end of the tongue comes into contact with said ramp.

14. The device according to any one of claims 8 and 9, wherein the inner wall of the handle is provided with a spur protruding in the vicinity of the 20 window and capable of being inserted into one of the two notches formed in the inner surface of the fault indicating tab, the cam being in the first (second, respectively) indexing position when the spur is housed in the notch (respectively). 25

15. The device according to the claim 13, wherein the fault indicating tab is situated across from the window when the spur is housed in the notch in the OFF position of the handle following an electrical fault. 2474480v1