Abstract:
The present invention concerns a shutoff apparatus that can be controlled in either front or side mode, consisting of a minimum number of parts and resulting in a simple, economical, mechanically dependable, and compact unit. The shutoff apparatus ( 1 ) is characterized in that it comprises a rotating control element ( 20 ) in the shape a star with four branches ( 22 ), provided with a profiled extremity ( 25 ) and connected to the control rod ( 5 ) oriented toward one or the other of the two control axles (A, B) corresponding to front and lateral control modes, respectively. It comprises a transmission element ( 30 ) connected to movable contacts ( 7 ) and equipped with inclined ramps transforming rotational movement by the control element ( 20 ) on one or the other of the two control axles (A, B) into translational movement by the movable contacts ( 7 ) between the released and engaged positions, and conversely. It also comprises a sudden actuation device ( 60 ) with two pistons ( 61 ) comprising two orthogonal V-shaped grooves ( 64 ) acting on the rotation of the control element ( 20 ) from a position of equilibrium and from a locking element ( 50 ) blocking the transmission element ( 30 ) in the released position until the position of equilibrium is reached.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention concerns a front or side controlled electrical shutoff apparatus for an electrical installation comprising at least one case equipped with at least one pair of connecting terminals for connection to at least one electrical conductor on said installation and connected to a pair of fixed contacts, said case comprising at least one movable contact and at least one control rod traversing said case, connected on the exterior to a manipulation device and on the interior to said movable contact by means of a transmission mechanism which displaces it between a released position, where the movable contact is separated from the fixed contacts and the electrical circuit is open, and an engaged position, where it touches the fixed contacts and the electrical circuit is closed.  
       BACKGROUND OF THE INVENTION  
       [0002]     Such shutoff apparatuses are commonly called switches, fusible switches, reverse switches, commutators, reverse commutators, etc., and they are designed to distribute energy throughout electrical installations or to supply industrial equipment, machine tools, etc., with alternating low voltage, in particular, for example, 380 V., with current ranging from several tens to several hundreds of amps.  
         [0003]     Depending upon the electrical installation, the configuration of the electrical control panels and installation options, these shutoff apparatuses are manually controlled using a manipulation device that may consist of a rotating handle placed either on the front, called a “front handle,” or on the side, called a “side handle,” or even a pivoting lever generally placed on the front. These shutoff apparatuses may be controlled automatically, depending upon the situation, by a motor associated with the front or side control rod.  
         [0004]     Depending upon whether front or side control is used, the transmission mechanism differs. Generally speaking, with front control, this transmission mechanism comprises a cam system for transforming the rotational movement of the handle, which is transmitted to the control rod, into translational movement by the movable contacts. With lateral control, this transmission mechanism is completed by a drive belt. In another mode currently used, the transmission mechanism is coupled with a rapid actuation device which, independent of the rotation speed of the handle or the pivoting of the lever, accelerates release and/or engagement as needed.  
         [0005]     Consequently, there is a need to design different shutoff apparatuses as a function of both the range of current and the control mode (front or side). This means that for the same range of current, one shutoff apparatus is manufactured in several versions depending upon whether it is controlled from the front or the side. Certain manufacturers have proposed shutoff apparatuses called polyvalent apparatuses that are designed for adaptation to both front and side controls. However, these polyvalent shutoff apparatuses have complex, heavy transmission mechanisms with a large number of pieces and are not mechanically reliable, particularly in terms of longevity. Moreover, this affects the size of these pieces of equipment.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention proposes overcoming these disadvantages with a shutoff apparatus that is polyvalent and responsive to all control modes, made with a minimum number of pieces, resulting in a simple, economical, mechanically reliable, standard size apparatus.  
         [0007]     To achieve this, the invention concerns a shutoff apparatus. The transmission mechanism comprises at least one rotating control element that can be coupled with the control rod facing one of the two orthogonal control axles corresponding to one of the two control modes, front or side, respectively, so as to make the control element turn on one of the control axles, and at least one transmission element coupled with the movable contact to transform the rotation by said control element on one or the other of the two axles into translational movement by said movable contact between the released position and the engaged position, and vice versa.  
         [0008]     In a preferred embodiment, the transmission mechanism comprises a rapid actuation device that cooperates with the rotating control element to make it turn automatically and quickly beyond a predetermined position of equilibrium.  
         [0009]     This rapid actuation device may comprise at least one piston movable in translation within the case and compelled by a spring means toward the rotating control element, the piston and the rotating control element being designed to cooperate with each other along the diagonal of the three sided cam so that while it is alternating between the released and engaged positions, and vice versa, the rotating control element pushes the piston to meet its spring at the beginning of its course up to the position of equilibrium, and then the piston, influenced by the spring, pivots the rotary control element beyond the position of equilibrium to the end of its course.  
         [0010]     Preferably, the rapid actuation means comprises two opposing pistons disposed symmetrically in relation to said rotating control element.  
         [0011]     The rotating control element may be shaped like a four-pointed star in two orthogonal planes of symmetry defining eight angled surfaces and four tips, and the piston may comprise two V-shaped grooves in two orthogonal planes of symmetry defining four angled ramps and four points.  
         [0012]     In the preferred embodiment the total course followed by the rotating control element when alternating between the released position and the engaged position, and conversely, is generally equal to 90° and its position of equilibrium is located essentially halfway between the released and engaged positions, that is, about 450.  
         [0013]     Advantageously, the rapid actuation device comprises at least one locking means designed to block the transmission element in at least the released position and at least as far as the transmission mechanism&#39;s position of equilibrium.  
         [0014]     This locking means may be coupled with the piston and controlled by a recall means to move between at least a locked position in which it blocks the transmission element in said released position, and an unlocked position in which it frees the transmission element for displacement into the engaged position.  
         [0015]     This locking element may be integral with the piston or it may consist of a piece that is separate from the piston.  
         [0016]     The case may advantageously comprise an intermediate plate disposed between the transmission element and the piston, equipped with guide openings for the piston and the locking means.  
         [0017]     In a preferred manner, the rotating control element and the transmission element are designed to cooperate with each other along the diagonal profile of the three-sided cam so that at least during the pivoting movement from the engaged position to the released position, the rotating control element turns freely on one or the other of the control axles, without displacing the transmission element from the beginning of its course to the position of equilibrium, then causes the transmission element to move translationally beyond the position of equilibrium to the end of its course.  
         [0018]     In the preferred embodiment, the rotating control element comprises at least one V-shaped extremity defining a tip and two angled surfaces that are symmetrical in relation to a plane passing through its axis of symmetry, and the transmission element comprises opposite the rotating control element at least two angled ramps with different slopes which cooperate with the profiled extremity of the rotating control element when it turns on one or the other control axles, respectively. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]     The features of the present invention will be better understood from the following description of one embodiment given by way of non-limiting example, with reference to the attached drawings, in which:  
         [0020]      FIG. 1A -D represent four different modes for the construction and/or control of the shutoff apparatus of the invention;  
         [0021]      FIG. 2  is an exploded perspective view of the shutoff apparatus of FIGS.  1  without its case, representing the two possible control modes: the front mode and the side mode;  
         [0022]     FIGS.  3 A-C are partial perspective views of the shutoff apparatus of FIG.  2  controlled in front mode and respectively in the released, equilibrium, and engaged positions;  
         [0023]     FIGS.  4 A-C are overhead views corresponding to FIGS.  3 A-C;  
         [0024]     FIGS.  5 A-B are partial perspectives of the shutoff apparatus of  FIG. 2  controlled in the lateral mode, respectively in the equilibrium and disengaged positions;  
         [0025]     FIGS.  6 A-C are side views corresponding to the shutoff apparatus of FIGS.  5 A-B, respectively in the engaged, equilibrium, and released positions; and  
         [0026]      FIG. 7  is a detailed perspective of the transmission cam. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]     With reference to the drawings, shutoff apparatus  1  of the invention may concern any type of shutoff apparatus such as a switch, a fusible switch, commutator, reverse commutator, etc., and it is designed to distribute electrical energy to industrial and/or domestic electrical installations, specifically, alternating low voltage over a range of current of from several tens to several hundreds of amps.  
         [0028]     It comprises an electrically insulated case  2  of standard dimensions that can be mounted on normal rails in electrical control panels. The number of pairs of connecting terminals  3  or poles is adapted to the number of phases or conductors in the electrical installation, for example, three, in the examples shown. These connecting terminals  3  use screws, but may use springs or any other type of connection.  
         [0029]     This type of shutoff apparatus  1  may be controlled by a manipulating element  4  outside the case  2  and mounted on the front surface or on the side and connected to a control rod  5 . FIGS.  1 A-D respectively illustrate four shutoff apparatuses  1  a-d controlled in four different modes: the front mode with a first control axle A, either using with handle  4   a  mounted on the front according to  FIG. 1A  and capable of rotating a quarter turn between two positions  0  and  1  or using lever  4   b  mounted on the front according to  FIG. 1B , pivoting 90° between two positions  0  and  1 , or in the side mode with a second control axle B perpendicular to the first, using one or two handles  4   c  mounted on the sides according to  FIG. 1C  and capable of rotating a quarter turn between two positions  0  and  1 . The lateral control mode permits shutoff apparatuses  1   d  of the same or different caliber to be joined. One example is illustrated in  FIG. 1D  where two identical shutoff apparatuses  1   d  are joined to double the available number of connecting terminals  3 , controlled simultaneously by a handle  4   d  mounted on one said of case  2  and an extending control rod  5  traversing the two cases  2 .  
         [0030]     An exploded view of the interior of shutoff apparatus  1  according to the invention is shown in  FIG. 2 . It comprises three pairs of connecting terminals with screws  3 , each coupled with a pair of fixed contacts  6 . To each pair of fixed contacts  6  there corresponds a movable contact  7  capable of opening or closing the electrical circuit between fixed contacts  6  in the same pair. Movable contacts  7  are each subject to a recall element  8  compelling them towards fixed contacts  6  and they are simultaneously displaced by exterior manipulating element  4  through control rod  5  and a transmission mechanism  10  between a released position, in which movable contacts  7  are spaced apart from fixed contacts  6  and the electrical circuit is open, and an engaged position, in which they are in contact with fixed contacts  6  and the electrical circuit is closed.  
         [0031]     Transmission mechanism  10  comprises a rotating control device  20  associated with control rod  5  oriented along the first or second control axle A, B corresponding to front or side control, respectively, and a transmission element  30  coupled with movable contacts  7  which transforms the rotation of control element  20  along one or the other of these control axles A, B into translational movement by movable contacts  7  between the released and engaged positions, and vice versa.  
         [0032]     Rotating control element  20  consists of a movable piece that is not attached to case  2  (not shown). It comprises two square notches  21  with orthogonal axes, associated with the two control axles A and B, to receive and engage directly with the corresponding extremity of control rod  5 , which is also square in section. Obviously, other types of connection may be used depending upon the section of control rod  5 . This rotating control element  20  has a star shaped section with four branches  22  in two symmetrical orthogonal planes, defining eight angled surfaces  23  and four tips  24 , with all the corners being rounded. The two planes of orthogonal symmetry are divided along an axis of symmetry shared with first control axle A. Rotating control element  20  comprises, opposite transmission element  30 , a V-shaped profiled extremity  25  defining a rounded tip forming a linear finger  26  and two angled surfaces  27  that are symmetrical relative to a plane passing through the two control axles A and B.  
         [0033]     Transmission element  20  comprises a bar  31  movable in translation relative to case  2  (not shown) and guided by the latter using complementary shapes such as ribs sliding inside rails  32 . This transmission element  30 , shown in detail in  FIG. 7 , comprises on one side, guide housings  33  for movable contacts  7  and on the other side, a block with multiple cams  40  opposite rotating control element  20 , a contact area  34  for a lock  50 , and a groove  35  for lock  50  to circulate in. The multiple-cam block  40  is centered on control axle A and comprises a flat base  41  surrounded by two semi-annular raised areas diametrically opposed in relation to this control axle A defining two inclined ramps  42 ,  43  with different slopes. Flat base  41  has an angular section extending about 45° and is followed by a first steeply sloped inclined ramp  42  with an angular section of about 45°. This first inclined ramp  42  is doubled and diametrically opposed in relation to control axle A. The height of this first inclined ramp  42  is essentially equal to the course of movable contacts  7  between the released and engaged positions. This flat base  41  and this first angled ramp  42  cooperate with linear finger  26  formed at the profiled extremity  25  of rotating control element  20  when it is rotating around first control axle A. Second angled ramp  43  is less steeply sloped, extends for a section of about 90°, is opposite first angled ramp  42 , doubled and diametrically opposed relative to control axle A. It cooperates with one of the angled surfaces  27  and the linear finger  26  on profiled extremity  25  of rotating control element  20  when it is rotating around second control axle B. Inclined ramps  42  and  43  with different slopes join each other two by two at a tip  44  forming an end ridge contained within a plane passing through the two control axles A and B.  
         [0034]     Transmission mechanism  10  also comprises a rapid actuator  60  with two pistons  61  disposed on either side of rotating control element  20  and movable in translation relative to case  2  (not shown) in opposite directions. Each piston  61  comprises a central groove  62  for freely receiving control rod  5  in the lateral mode and is subject to spring  63  compelling it towards rotating control element  20  to ensure that it is in the correct stable position relative to case  2  and the other mechanisms. Each piston  62  comprises, opposite rotating control element  20 , two V-shaped grooves  64  along two orthogonal planes defining four inclined ramps  65  and four tips  66 , with all the corners being rounded.  
         [0035]     This rapid actuator  20  also comprises at least one locking element  50  disposed between at least one of pistons  61  and transmission element  30 . It moves translationally relative to case  2  (not shown) between at least one locked position in which it blocks transmission element  30  in at least the released position, and one unlocked position in which it frees that element for displacement into the engaged position. This lock element  50  is associated with one of the pistons  61  which drives it in the opposite direction from control element  20 , and is subject to recall means  51  driving it in the other direction towards control element  20 . In the example shown this lock element  50  consists of an L-shaped piece separate from piston  61  and translationally connected to it through an opening  27 . In other variations that are not shown, it may be integral with the piston and have some degree of freedom to rotate relative to it. It is even possible to provide two lock elements  50  working simultaneously and in opposition.  
         [0036]     Case  2  (not shown) comprises an intermediate plate  70  disposed between transmission element  30  and the unit formed of the locking element  20  and pistons  61 . This intermediate plate  70  specifically comprises a translational guide groove  71  for locking means  50  and translational guide openings  72  for pistons  61 . It allows guided translational movement by these pieces and also distributes the restraining forces of the lock when it is in the locked position, thus sparing pistons  61 .  
         [0037]     The operation of shutoff apparatus  1  of the invention will now be described with reference to  FIGS. 3 and 4 , corresponding to front control mode, that is, using control axle A.  
         [0038]      FIGS. 3A and 4A  illustrate shutoff apparatus  1  in the released position. Rotating control elements  20  and transmission control elements  30  are in contact at their tips  26 ,  24 , with linear finger  26  resting on tip  44  of multiple-cam block  40 . Pistons  61  block rotating control element  20  in a stable position, with their spring means  63  being extended. Rotating control element  20  is in a stable position, given that its opposing branches  22  are housed in openings  64  in pistons  61 . Locking element  50  blocks transmission element  30  in the released position, with its recall means  51  being extended. Recall elements  8  on movable contacts  7  are compressed.  
         [0039]      FIGS. 3B and 4B  illustrate shutoff apparatus  1  in the released position of equilibrium. The operator has turned the exterior handle  4  (not shown) for a one-eighth rotation, driving rotating control element  20  to a first portion on its course, a one-eighth turn on the diagonal of control rod  5  along control axle A. Tips  24  of the two opposing branches  22  of the star housed in the base of corresponding openings  64  in pistons  61  slide along corresponding inclined ramps  65 , causing pistons  61  to move back and compressing spring means  63  toward tips  24 , reaching points  66  on pistons  61 , marking the position of equilibrium. Simultaneously, the return of one of the pistons  61  drives locking element  50  and compresses its recall means  51 . Locking element  50  maintains transmission element  30  in the recessed position while it is in contact zone  34  and until it is opposite circulation groove  35 .  
         [0040]      FIGS. 3C and 4C  illustrate shutoff apparatus  1  in the engaged position. By rotating exterior handle  4 , the operator has surpassed the position of equilibrium, activating rapid actuation means  60  to pivot very quickly from the released position to the engaged position. When tips  24  of the two opposing branches  22  of the star leave corresponding points  66  on pistons  61 , the resistance on spring means  63  is nullified, they become extended, and move closer to pistons  61  of rotating control element  20  while quickly and automatically causing it to rotate along the second portion of its course for a one-eighth rotation. Simultaneously, as locking element  50  has left contact zone  34  and faces circulation groove  35 , no longer exerting any resistance on recall elements  8  of movable contacts  7 , these elements relax, pushing on movable contacts  7  and causing transmission element  30  to move up into the engaged position. Simultaneously, profiled extremity  25  of rotating control element  20  lodges in multiple-cam block  40 , with linear finger  26  abutting the flat base  41 , allowing it to rotate on the second portion of its course. Shutoff apparatus  1  is in the engaged position.  
         [0041]     To move into the released position the operator must turn exterior handle  4  in the reverse direction. On the first portion of the course, a one-eighth rotation, rotating control element  30  rotates for a one-eighth turn without any effect on transmission element  30 , while linear finger  26  circulates inside flat base  42  of multiple-cam block  40 . Simultaneously, tips  24  of the two other branches  22  of the star become active and slide along inclined ramps  65  of pistons  61 , making them move back and compressing their spring means  63  until they reach corresponding tips  66 , marking the position of equilibrium. Simultaneously, one of the pistons  61  drives locking element  50  with it, compressing its recall means  51 .  
         [0042]     Past the point of equilibrium, pistons  61  compelled by recall means  63  quickly and automatically cause control element  20  to rotate on the second portion of its course for a one-eighth rotation until it reaches a stable position with two opposing branches  22  of the star being housed in corresponding openings  64  in pistons  61 . Simultaneously, linear finger  26  of profiled extremity  25  of rotating control element  20  circulates on the first steeply sloped inclined ramps  42 , causing transmission element  30  to move back, movable contacts  7  to separate from fixed contacts  6 , and recall elements  8  to compress. When rotating control element  20  has completed its course and the released position has been attained, locking element  50  moves near rotating control element  20  due to the action of its recall means  51 , abutting contact zone  34  of transmission element  30  and blocking it in the released position. The pushing forces of recall elements  8  of movable contacts  7  are thus transmitted to locking element  50  and distributed within intermediate plate  70 . Because of this design, pistons  61  are not subjected to any interfering forces that would disrupt their translational movement.  
         [0043]     The operation of shutoff apparatus  1  of the invention in side control mode is essentially identical. With reference to FIGS.  5 A-B, shutoff apparatus  1  is shown in equilibrium position and in engaged position, respectively, with the released position being the same as  FIG. 3A . Control rod  5  is connected to rotating control means  20  along the second control axle B, causing it to rotate about this same control axle B in the direction in which exterior handle  4  (not shown) is rotated or pivoted. On the first part of the course, the two opposite branches  22  of the star circulate along corresponding inclined ramps  65  diametrically opposed to pistons  61 , causing them to move them back. Simultaneously, profiled extremity  25  of rotating control element  20  turns freely without colliding into transmission element  30 , the latter being blocked in the released position by locking element  50  as far as the equilibrium position (cf.  FIG. 5A ). Beyond this equilibrium position, pistons  61  quickly and automatically cause control element  20  to rotate along the second portion of its course, said rotation being possible due to the fact that profiled extremity  25  of rotating control element  20  remains outside multiple-cam block  40 . Simultaneously, locking element  50  frees transmission element  30 , which moves upward into the engaged position (cf.  FIG. 5B ).  
         [0044]     The pivoting movement of shutoff apparatus  1  of FIGS.  5 A-B from the engaged to the released position is illustrated by FIGS.  6 A-C.  FIG. 6A  corresponds to the engaged position of  FIG. 5B . The operator actuates exterior manipulating element  4  to cause control element  20  to rotate about control axle B for the first part of its course, for a one-eighth rotation, until the equilibrium position is attained (cf.  FIG. 6B ). This rotation is possible because profiled extremity  25  of rotating control element  20  is located outside multiple-came block  40  and does not conflict with it. In the equilibrium position, one of the inclined surfaces  27  of this profiled extremity  25  comes into contact with one of the second slightly inclined ramps  43  on multiple-cam block  40 . Having surpassed the equilibrium position, when pistons  61  quickly and automatically cause control element  20  to rotate on the second portion of its course for a one-eighth rotation, linear finger  26  provided on this profiled extremity  25  circulates along the second inclined ramp  43  on multiple-cam block  40 , causing transmission element  30  to move back into the released position (cf.  FIG. 6C ), simultaneously locked by locking element  50 .  
         [0045]     This description clearly demonstrates that the invention achieves its stated goal, that is, a shutoff apparatus  1  equipped with a simple mechanism that can be controlled equally well in either the front or side mode. This option permits use of single model of a shutoff apparatus for a range of current or caliber and leaves the choice of command mode up to the end user. Moreover, it appears that the kinematic chain is very short, allowing optimal transmission of movement with no inertia, and limiting mechanical wear on the moving parts. The parts comprising this shutoff apparatus are primarily made of molded or injected synthetic material, which may or may not be reinforced, depending upon the degree of mechanical resistance desired, and with a low coefficient of friction, particularly the parts that are in sliding contact, i.e., control element  20 , pistons  61  and transmission element  30 .  
         [0046]     The present invention is not limited to the exemplary embodiment described, but extends to all modifications and variations obvious to a person skilled in the art while still remaining within the scope of protection defined in the attached claims.