Patent Grant
8071898
The present application hereby claims priority under 35 U.S.C. §119 on German patent application number DE 10 2007 040 163.0 filed Aug. 21, 2007, the entire contents of which is hereby incorporated herein by reference.
Embodiments of the invention generally relate to a switching device, in particular a circuit breaker. For example, embodiments may relate to a switching device including a switching shaft for mounting a rotary contact link with two switching contacts and a pair of fixed contacts, which pair interacts with the rotary contact link, for connection to in each case one current path. The fixed contacts and the current paths may be designed, in at least one embodiment, in such a way that the rotary contact link is rotated from a closed position in the direction of an open position in the event of an overcurrent or a short circuit. The switching shaft may include, in at least one embodiment, a transversely running cutout for mounting the rotary contact link, which protrudes on both sides out of the switching shaft. The rotary contact link may be connected, via at least one spring element, in at least one embodiment, to the switching shaft for applying a contact force in the closed position and for the rotary contact link to remain in the open position.
Embodiments of the invention furthermore may generally relate to a multipole switching device arrangement with at least two such switching devices with at least one coupling bolt for connecting, in a manner fixed against rotation, the respective switching shafts to one another.
With switching devices, in particular low-voltage switching devices, the current paths switch between an electrical supply device and loads and therefore their operating currents. This means that, by way of current paths being opened and closed by the switching device, the connected loads can safely be switched on and off.
The translation DE 693 04 374 T2 of the European patent EP 0 560 697 B1 has disclosed a low-voltage circuit breaker in an insulating housing, which includes a rotary contact link, a pair of fixed contacts, which pair interacts with the mentioned contact link, power supply conductors for feeding the mentioned fixed contacts, a switching shaft with a transversely running cutout for mounting, with play, the contact link, which protrudes on both sides out of the switching shaft, and at least one pair of tension springs, which are arranged between the switching shaft and the contact link. The fixed contacts are designed in such a way that they generate electrodynamic forces repelling the contact link in the direction of a repelling open position if a short-circuit current is flowing through them. The tension springs serve the purpose of ensuring a contact pressure, which is exerted by the contact link on the fixed contacts, in the closed position of the circuit breaker and at the same time of making a rotation of the contact link possible under the effect of the mentioned electrodynamic forces in the direction of the repelling open position.
The mentioned springs are arranged symmetrically on both sides of the axis of rotation of the contact link and each have an end mounted on the contact link. An opposite end of the mentioned springs is mounted on a rod, which is arranged in a latching notch of the switching shaft in such a way that it is displaceable in sliding fashion. The mentioned contact link has a pair of control cams, which are arranged symmetrically with respect to the mentioned axis and are each designed in such a way that they interact with one of the rods in the end section of the repulsive excursion of the contact link in order to brake the movement of the contact link.
An electrical low-voltage switching device, such as a circuit breaker or a contactor, for example, has, for the purpose of switching the current paths, one or more so-called main contacts, which can be controlled by one or else more control magnets or electromagnetic drives. In principle, the main contacts in this case include a movable contact link and fixed contact pieces, to which the load and the supply device are connected. In order to close or open the main contacts, a corresponding closing or opening signal is emitted to the electromagnetic drive, whereupon said contacts act with their armature on the movable contact links in such a way that the contact links perform a relative movement in relation to the fixed contact pieces and either close or open the current path to be switched. In the context of the invention made, only switching devices with a rotary contact link are taken into consideration.
In at least one embodiment of the invention, a switching device with a rotary contact link is specified, which is mounted in the switching shaft alternatively in a sprung manner.
In at least one embodiment of the invention, a suitable multipole switching device arrangement is specified, with at least two such switching devices.
According to at least one embodiment of the invention, the rotary contact link has at least one groove-shaped longitudinal cutout, which is arranged within and along the transversely running cutout in relation to the switching shaft. Two grooves, which are arranged radially opposite one another, with in each case a bent or arcuate profile are provided in the cutout of the switching shaft, the respective two ends of said grooves being positioned radially further outward than the respective central region thereof. “Radial” refers to directions toward the axis of rotation of the switching shaft and away from it. In each case one groove being connected to the at least one groove-shaped longitudinal cutout via a transverse bolt guided therebetween. At least one prestressed spring element being provided which pushes the respective transverse bolt radially outward.
The particular advantage is the fact that the opening response of the rotary contact link can be set precisely by means of the groove guide according to at least one embodiment of the invention. The groove guide makes it possible for the rotary contact link to be rotated back reliably and quickly into the closed position again when the central region between the respective two groove ends is not reached. If, however, the rotary contact link, or the transverse bolts guiding the rotary contact link, reaches the central region between the respective two groove ends, immediate, quick and irrevocable rotation of the rotary contact link into the open position takes place. The transverse bolt typically has a circular cross section, at least in the region of the grooves and in the region in which it passes through the groove-shaped longitudinal cutout in the rotary contact link.
In accordance with one embodiment, the at least one groove-shaped longitudinal cutout and the two grooves have an identical groove width. As a result, more precise guidance of the rotary contact link along the grooves is possible.
In accordance with a further embodiment, the two grooves are arranged in point-symmetrical fashion with respect to the axis of rotation of the switching shaft. As a result, more precise guidance of the rotary contact link about the axis of rotation is possible.
In accordance with a particularly advantageous embodiment, the two ends of the respective grooves are arranged on a radially outer region of the switching shaft. In each case one bend or an elbow is formed between the respective two ends. The two grooves run straight between the respective bend and the respective two ends. As a result of the bend, a particularly precise switchover response between the closed position and the open position of the switching device is possible. The straight groove profile between the respective bend and the respective two ends makes it possible for the transverse bolts to be moved in the grooves with little resistance.
In particular, the rotary contact link is mounted in the transversely running cutout of the switching shaft by way of the two transverse bolts in such a way that the rotary contact link is snapped back tangentially into the closed position or into the open position once the respective bends have been reached. “Tangentially” denotes directions about the axis of rotation of the switching shaft.
In accordance with a further embodiment, the two transverse bolts in the closed position of the switching device are guided toward the first end of the respective groove. The two transverse bolts in the open position are guided toward the second end of the respective groove. In this case, the groove length from the respective first end to the bend is approximately twice to four times as long as the groove length from the respective second end to the bend. The L shape of the two grooves formed thereby allows for a high compensation path for a corresponding rotary movement of the rotary contact link preferably in the event of an overcurrent. The shorter limb, which is aligned more in the longitudinal direction of the groove-shaped longitudinal cutout in the rotary contact link, ensures that the rotary contact link reliably remains in the open position. Preferably, the obtuse angle formed between the two L limbs is in a region of 100° to 140°, in particular is approximately 120°.
In accordance with an example embodiment, the switching shaft includes two axially opposite switching shaft segments, which are formed in mirror-inverted fashion and in whose axial center the transversely running cutout for mounting the rotary contact link is arranged. “Axially” denotes directions parallel to the axis of rotation of the switching shaft. The at least one groove-shaped longitudinal cutout in the rotary contact link is axially continuous, with the result that the two transverse bolts can be passed through for the purpose of guiding the rotary contact link. In comparison with the single-part solution, i.e. with only one switching shaft segment, even safer guidance of the interposed rotary contact link is possible. At the same time, the at least one spring element and the transverse bolts are protected more effectively against external environmental influences, such as dust, switching gases, residues from shutdown operations, for example.
In accordance with one embodiment, only a (single) groove-shaped longitudinal cutout is provided in the rotary contact link. Furthermore, only a (single) spring element is provided which pushes the two transverse bolts radially outward.
In particular, the spring element is arranged in the groove-shaped longitudinal cutout in the rotary contact link. In this case, the spring element pushes the two transverse bolts radially outward. This simplifies: the design of the switching device further.
As an alternative or in addition, the at least one spring element is arranged in the region of the respective transversely running cutout between the respective switching shaft segment and the rotary contact link. The at least one spring element in each case pushes the two transverse bolts radially outward. In particular, a spring element is arranged in each of the two transversely running cutouts. The particular advantage of this arrangement is the fact that more space is possible for the installation of in particular the two spring elements in comparison with the introduction of the springs in the groove-shaped longitudinal cutout in the rotary contact link. As a result, a higher spring force can be realized.
The at least one spring element is preferably a cylinder spring. It can be accommodated, for the purpose of applying the spring force, in two pressure sleeves, which introduce the spring force into the respective transverse bolt. The spring force can alternatively be introduced by the spring element via its two ends directly into the transverse bolts.
As an alternative or in addition, the at least one spring element can be a leaf spring. It can be designed to have a single or double clasp. Preferably, the leaf spring has corresponding shaped-out portions for introducing the spring force into the two transverse bolts.
At least one embodiment is directed to a multipole switching device arrangement, which has at least two, in particular three, switching devices according to the invention. The switching device arrangement has at least one coupling bolt for connecting, in a manner fixed against rotation, the respective switching shafts to one another.
The invention and advantageous embodiments of the invention will be described in more detail below with reference to the following figures, in which:
Various example embodiments will now be described more fully with reference to the accompanying drawings in which only some example embodiments are shown. Specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. The present invention, however, may be embodied in many alternate forms and should not be construed as limited to only the example embodiments set forth herein.
Accordingly, while example embodiments of the invention are capable of various modifications and alternative forms, embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit example embodiments of the present invention to the particular forms disclosed. On the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the invention. Like numbers refer to like elements throughout the description of the figures.
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments of the present invention. As used herein, the term “and/or,” includes any and all combinations of one or more of the associated listed items.
It will be understood that when an element is referred to as being “connected,” or “coupled,” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected,” or “directly coupled,” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between,” versus “directly between,” “adjacent,” versus “directly adjacent,” etc.).
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper”, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, term such as “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein are interpreted accordingly.
Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or section from another region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present invention.
The switching device 1 shown has a switching shaft 2 for mounting a rotary contact link 5 with two switching contacts 6 and a pair of fixed contacts 3, which pair interacts with the rotary contact link 5, for connection to in each case one current path 4. The contacts 3, 6 are arranged in such a way that they are tangentially opposite one another in relation to the axis of rotation 9 of the switching shaft 2. In other words, the flat contacts 3, 6 substantially lie in a plane running through the axis of rotation 9. The fixed contacts 3 and the current paths 4 are designed in such a way that the rotary contact link 5 is rotated from a closed position in the direction of the open position in the event of an overcurrent or a short circuit. In this case, electrodynamic forces which are caused by mutually repelling currents flowing through in the current paths 4 and in the rotary contact link 5 are critical. The electrodynamic forces bring about a torque, which moves the rotary contact link 4 in the direction of the open position. The switching shaft 2 furthermore has a transversely running cutout 14 for mounting, with play, the rotary contact link 5, which protrudes on both sides out of the switching shaft 2. The transversely running cutout 14 is formed by two radially opposite stops 11 for the rotary contact link 5. They extend in the axial direction with respect to the rotary contact link 4. They each have an arcuate stop face 15, which faces the central region of the rotary contact link 5. In addition, the rotary contact link 5 is connected, via a spring element 12 in the form of a cylinder spring, to the switching shaft 2 for applying a contact force in the closed position and for the rotary contact link 5 to remain in the open position.
According to an embodiment of the invention, the rotary contact link 5 shown has at least one groove-shaped longitudinal cutout 10, which is arranged within and along the transversely running cutout 14 in relation to the switching shaft 2. In the example in
Furthermore, in the example in
The groove-shaped longitudinal cutout 10 in the rotary contact link 5 has an identical groove width to the grooves 7, with the result that the transverse bolts 8 can precisely follow the respective groove 7 in the event of the onset of a rotary movement. At the same time, the cylinder spring 12 is compressed as the rotary movement increases by way of the transverse bolts 8, which migrate inward from the view of the groove-shaped longitudinal cutout 10. In order to fix the rotary contact link 5 axially, the switching shaft 2 can have a covering disk (not shown). This covering disk can be fixed on the stops 11, for example by way of two screws.
By way of example, a spring element 12 in the form of a cylinder spring 12 is arranged in the region of the respective transversely running cutout 14 between the respective switching shaft segment 21 and the rotary contact link 5. The spring element 12 in the process pushes the two transverse bolts 8 radially outward. In order to avoid bending or deflection of the cylinder spring 12 during compression, a spring sleeve 16 is inserted at the two ends of the cylinder spring 12. This spring sleeve 16 has in each case one spring plate 17, on which the cylinder spring rests. An adjoining pressure piece 18, which is matched to the shape of the transverse bolts 8, finally transfers the spring force to the respective transverse bolt 8.
The switching device 1 shown is in particular a circuit breaker. The switching device 1 has a switching shaft 2 for mounting (with play) a rotary contact link 5 with two switching contacts 6 and a pair of fixed contacts 3, which pair interacts with the rotary contact link 5, for connection to in each case one current path 4. The fixed contacts 3 and the current paths 4 are designed in such a way that the rotary contact link 5 is rotated from a closed position in the direction of an open position in the event of an overcurrent or a short circuit. The switching shaft 2 includes two axially opposite switching shaft segments 21, in whose axial center a transversely running cutout for mounting the rotary contact link 5, which protrudes on both sides out of the switching shaft 2, is arranged.
In particular, in each case two guide grooves 42, 43, which run substantially circularly, are opposite one another and adjoin the rotary contact link 5, are provided in the two switching segment shafts 21. The rotary contact link 5 has two radially opposite apertures 48, which are arranged between the guide grooves 42, 43, in each case one ball 41 being introduced in the aperture 48. In addition, the guide grooves 42, 43 are shaped out in terms of their groove depth in such a way that, in the event of a rotary movement of the rotary contact link 5 from the closed position in the direction of the open position, the balls 41 which are carried along by the apertures 48 follow a radially and axially running oblique plane. This can be seen in the example in
It is particularly advantageous that no separate rotary stops 11 are required, as shown, for example, in
Alternatively, in each case (only) one guide groove, which runs substantially circularly, are opposite one another and adjoin the rotary contact link 5, can be provided in the two switching segment shafts 21. In this case, the rotary contact link 5 is mounted rotatably, and therefore without any play, at a fulcrum 40, such as in a rotary bolt, for example. The rotary contact link 5 has an aperture 48, which is arranged between the guide grooves 42, 43 and in which a ball 41 is introduced. The guide grooves 42, 43 are shaped out with respect to their groove depth in such a way that, in the event of a rotary movement of the rotary contact link 5 from the closed position in the direction of the open position, the ball 41 carried along through the aperture 48, follows a radially and axially running, oblique plane. At the end of the guide groove 42, 43, the ball 48 can latch in a latching pocket 47 shaped out there in such a way that the rotary contact link 5 remains in the open position formed by the latching.
Furthermore, a latching spring element (not illustrated in any more detail) can be arranged in the latching pocket 47 and pushes the ball 41 axially into the latching pocket 47. The depth and the shape of the latching pocket 47 are preferably designed in such a way that the rotary contact link 5 can be moved into the closed position again, for example by way of a jolt.
Further, elements and/or features of different example embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.
Still further, any one of the above-described and other example features of the present invention may be embodied in the form of an apparatus, method, system, computer program and computer program product. For example, of the aforementioned methods may be embodied in the form of a system or device, including, but not limited to, any of the structure for performing the methodology illustrated in the drawings.
Even further, any of the aforementioned methods may be embodied in the form of a program. The program may be stored on a computer readable media and is adapted to perform any one of the aforementioned methods when run on a computer device (a device including a processor). Thus, the storage medium or computer readable medium, is adapted to store information and is adapted to interact with a data processing facility or computer device to perform the method of any of the above mentioned embodiments.
The storage medium may be a built-in medium installed inside a computer device main body or a removable medium arranged so that it can be separated from the computer device main body. Examples of the built-in medium include, but are not limited to, rewriteable non-volatile memories, such as ROMs and flash memories, and hard disks. Examples of the removable medium include, but are not limited to, optical storage media such as CD-ROMs and DVDS; magneto-optical storage media, such as MOs; magnetism storage media, including but not limited to floppy disks (trademark), cassette tapes, and removable hard disks; media with a built-in rewriteable non-volatile memory, including but not limited to memory cards; and media with a built-in ROM, including but not limited to ROM cassettes; etc. Furthermore, various information regarding stored images, for example, property information, may be stored in any other form, or it may be provided in other ways.
Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2007 040 163 | Aug 2007 | DE | national |
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| Number | Date | Country | |
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| 20090057112 A1 | Mar 2009 | US |
