Abstract:
It permits a pulling movement to be transferred or not to the bolt of the lock when turning the internal or external handles attached to separate square-section shafts belonging to clutch elements and which can have independent rotation or they can do so integrally.  
     The first clutch element ( 15 ) connected to the outside handle ( 6 ) possesses a prismatic projection ( 22 ) with a radial orifice into which fits a pulling pin ( 24 ) assisted by a spring ( 25 ) and able to be displaced in order to be introduced into a slot ( 32 ) of the second clutch element ( 16 ). The movement is controlled by a motor ( 11 ) with a worm-screw ( 12 ) linked to a spring ( 38 ) which can manage to displace a thruster rocker arm ( 27 ) which makes contact with said pulling pin ( 24 ). There exists an emergency device defined by a rod ( 35 ) and another spring ( 38 ) linked to said thruster rocker arm ( 27 ).

Description:
OBJECT OF THE INVENTION  
       [0001]     As stated in the title of this descriptive specification, the present invention refers to a clutch mechanism couplable to door locks with locking bolt operated by handles or knobs, which incorporates notable advantages compared to mechanisms currently existing and having the same end, and is above all conceived with the aim of having certain narrow dimensions in order to prevent it from projecting too much with respect to the doors in which it is fitted, and that it should include a minimum number of pieces and be able to be used both in a normal position and reversed so that it can be adapted to any kind of door, with the consequent advantages of assembly leading to economic advantages.  
         [0002]     All the component elements are interconnected together in such a way that there is no weakening and the mechanism is very compact.  
       PRIOR ART OF THE INVENTION  
       [0003]     There are basically two inventions making up the prior art: invention patent EP 0848779 and invention patent U.S. Pat. No. 6,286,347.  
         [0004]     The first of them describes a clutch mechanism for the interconnection for locking, blocking and unblocking of the lock, which can be displaced by the inside handle and also by means of the outside handle via an actuator.  
         [0005]     A motor is provided which, by means of a spring shaft, connects with a screw which permits displacement of a drive lever, which acts on a thrust arm or injector with a spring with pushes said arm outwards. This arm is in turn in contact with another coupling arm capable of being introduced against the action of a spring, into a slot of a rotating drive disc connected to the arm of the lock. An arched projection has likewise been provided in order to allow the coupling arm to rotate outside of the line of the arm of the injector, there existing a gap in said arched projection in order to allow the alignment and engagement between said arms.  
         [0006]     Moreover, invention patent U.S. Pat. No. 6,286,347 describes a variant of the above patent in that the arm is connected to an arched transverse member where it supports the coupling arm. In this case, the way in which the coupling arm is pushed in order to be introduced into the slot of the drive disc is via this transverse guide member.  
         [0007]     The number of pieces required in the solutions raises problems of dimensioning, and the result is a unit of considerable thickness which projects too much when it is fitted to doors.  
         [0008]     Equally, the actual functional requirements of the different pieces means that its application is very limited.  
         [0009]     When the lock is operated, the play between the spring of the drive lever and those for the thrust arm and the coupling arm, along with the alignment of these in the gap in the guide member, also raise problems in the stabilisation and compacting of the lock, which shows positions that are certainly weakened when the outside handle is displaced.  
       DESCRIPTION OF THE INVENTION  
       [0010]     In general terms, the clutch mechanism couplable to door locks with locking bolt operated by handles or knobs, forming the object of the present invention, is enclosed within a casing which will be superimposed on the outside of the door and coupled to the square-section shaft of the actuation system for the locking bolt. By means of this clutch mechanism, a pulling movement is or is not transmitted to the bolt from the outside.  
         [0011]     Engagement of the clutch is preferably carried out with the actuation of a small motor inside the casing which produces the rotation of a worm-screw which in turn controls the displacement of a radial pin which, when actuated, performs the clutch operation. When the mechanism is at rest the pin is retracted and the rotation of the handle or knob on the outside does not entail pulling of the lever which causes the displacement of the locking bolt.  
         [0012]     Instead of being a motor, the drive unit can be replaced with another means, such as for example a numeric or alphanumeric key-pad or any other electronic control device, or even by means of a mechanical mechanism.  
         [0013]     The clutch mechanism itself consists of two pieces rotating with respect to each other and coaxial, one of which is integral with the square-section shaft which has access to the outside of the door. The other clutch element is aligned with it and has a housing for inserting of the square-section shaft as an extension, which traverses the tumbler of the lock embedded in the door and reaches as far as the inside where it is connected to the inside handle or knob.  
         [0014]     When the outside handle is turned, no movement is obtained in the locking bolt if this second element, connected to the inside handle, is not connected to the clutch. When both elements are interconnected then the locking bolt is allowed to be displaced to its opening position.  
         [0015]     The element making up the clutch is defined by a pin which occupies a radial position in one of the clutch elements, which is able to be introduced into a notch or slot provided in the other clutch element so that they both become integral with each other when they rotate.  
         [0016]     The pin has an end that is radially further away and is not the operational end as far as the receiver notch is concerned, and it is assisted by a spring which keeps it retracted in such a way that its exit is prevented when support is established with an arched guide concentric with the axis of rotation of the handles or knobs, provided in the interior body. This same end of the pulling pin is also in contact with a thruster rocker arm which is forced to rotate when the worm-screw of the drive unit does so, with the mediation of a spiral spring with its ends extended in separate arms, one of which rests between two contiguous spirals of the worm-screw while the other is retained in a projection of the rocker arm. When the arm connected to the worm-screw approaches at an angle with respect to the arm attached to the thruster rocker arm, the latter is displaced at an angle pushing the pin and forcing it to become introduced into the notch of the second element of the clutch mechanism. Under these conditions, when the outside handle is turned, retraction of the locking bolt does indeed take place as the two square-section shafts linked to the respective elements of the clutch system become integral with each other.  
         [0017]     At the moment in which the outside handle ceases to be turned and it returns to its rest position, the pin exits from the slot due to the action of the coaxial spring which assists it, since the thruster rocker arm will already have receded to its original housing position with respect to the said pin.  
         [0018]     As we will see later on in relation to the figures, provision has also been made so that in the event that the access control mechanism fails to work, the thruster rocker arm would not move in an angle in order to push the pin and produce engagement of the clutch. In this case there exists an emergency system which is activated by means of an emergency key the cam of which axially drives a sliding lever which acts on the arm of a second spring similar to the previous one and whose other end pushes the rocker arm so that it is displaced at an angle in the same way as was done by means of the worm-screw.  
         [0019]     In order to facilitate an understanding of the characteristics of the invention and forming an integral part of this descriptive specification, some drawings are attached in which figures, on an illustrative rather than limiting basis, the following has been represented: 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1 .—Is a partial view in profile of a door fitted with a lock provided with the clutch mechanism object of the invention.  
         [0021]      FIG. 2 .—Is a view similar to  FIG. 1  with the clutch mechanism applied to a different lock.  
         [0022]      FIG. 3 .—Is a perspective exploded view of the components of the clutch mechanism object of the invention.  
         [0023]      FIG. 4 .—Is a plant view of the same clutch mechanism as in  FIG. 3 , with all components assembled, with the exception of the cover enclosing the casing and in a door closed position and without actuating the motor.  
         [0024]      FIG. 5 .—Is a similar view to  FIG. 4 , when the outside handle has been turned and the door cannot be opened, or the bolt cannot be retracted.  
         [0025]      FIG. 6 .—Is a similar view to  FIGS. 4 and 5 , with the clutch mechanism in the rest position but with the motor actuated producing engagement of the clutch which will permit the door to be opened when the outside handle is turned.  
         [0026]      FIG. 7 .—Is a similar view to  FIG. 6 , under the same conditions as the latter but with the outside handle having been turned.  
         [0027]      FIG. 8 .—Is a similar view to  FIG. 4 , once the inside handle has been turned.  
         [0028]      FIG. 9 .—Is a similar view to  FIG. 4 , once the emergency opening has been actuated so that the clutch can be operated in order to permit opening when the outside handle is turned.  
         [0029]      FIG. 10 .—Is a perspective view of the same clutch mechanism in the rest position as shown in  FIG. 4 .  
         [0030]      FIG. 11 .—Is a perspective view similar to that of  FIG. 10 , from the opposite side.  
         [0031]      FIG. 12 .—Is a transverse cross-section in longitudinal elevation of the same clutch mechanism, in the rest position.  
         [0032]      FIG. 13 .—Is an enlarged detail of the actual clutch mechanism, in the declutched position or position of retraction of the pin with respect to the receiver notch. 
     
    
     DESCRIPTION OF THE PREFERRED FORM OF EMBODIMENT  
       [0033]     Making reference to the numbering adopted in the figures, the clutch mechanism couplable to door locks with locking bolt operated by handles or knobs, which the invention proposes, is referenced in general with the number  1  and its location can be seen diagrammatically in  FIG. 1 . It is couplable to the lock  2  or  2 ′ attached to the side of the door  3  and whose locking bolt  4  is actuated by turning the inside  5  or outside  6  handle fitted in the ends of the square-section shaft  7  when engagement of the clutch has taken place, as we will see later on. The clutch mechanism  1  remains hidden beneath the plate of the lock  8  which can in turn consist of a frame covered with an embellisher.  
         [0034]     It contains an interior body  10  which houses virtually all the mechanisms and a protective cover  9  integral with the above and which provides anti-drill protection.  
         [0035]     As drive unit, a motor  11  has been provided which, via the corresponding transmission body (not represented), causes a worm-screw  12  to rotate.  
         [0036]     In  FIGS. 1 and 2  it can be seen that a reader  13  has been provided, which is powered by batteries  14  in order to permit reading of an electronic card.  
         [0037]     The clutch mechanism includes the clutch elements  15  and  16 , the element  15  being the one which we will call the first clutch element and is connected to the outside handle  6 , while the other clutch element, or second element  16 , is connected to the inside handle  5  and is integral with the square-section shaft  17  (see  FIG. 3 ) and is the one that acts on the locking bolt  4 . This second clutch element  16  constitutes in itself the element that is connected to the locking bolt of the lock and which, when turning, whether due to the actual inside handle  5  or due to the mediation of the clutch element  16  via the outside handle  6  when these elements are interconnected, as we will see later on, permits said locking bolt to be displaced to its opening position.  
         [0038]     The first clutch element  15  offers a square-section spike  18  for connection with the outside handle  6 , this spike  18  ending in the head or disc  19  in which, perpendicular to the plane of said disc  19  and via its periphery, provision has been made for a tab  20  which enables the end of the spring  21  to be supported, the other end of which is supported on a projection of the interior body  10 , as is habitual, so that it can recover its initial rest position. The rotary displacement of the first clutch element  15  is done against the action of said spring  21 .  
         [0039]     Also provided in that head or disc  19  is a prismatic projection  22  arranged to be diametrically opposite to the tab  20 , in which an orifice  23  is made in which is fitted the pulling pin  24  which is constantly pushed towards the outside of the radial orifice  23  (see  FIG. 3 ) and in the direction away from the axis of rotation of the second clutch element  16  by the action of the coaxial spring  25  which assists it. The length of this pulling pin  24  is such that its end that is radially furthest away, when it projects due to the action of its spring  25  through the lower part of the prismatic projection  22 , is at all times in contact with the arched support guide  26  of the interior body  10  (best seen in  FIG. 3 ).  
         [0040]     In turn, the end of the pulling pin  24  is simultaneously in contact with the edge of the thruster rocker arm  27  which rotates in an oscillating fashion around the axis  28  and is assisted by the spring  29  rolled around the pivot which defines the axis  28  of oscillation of the thruster rocker arm  27  and in such a way that one of its ends (referenced with  30 ) intercepts the worm-screw  12  driven by the motor  11 . The other end  31  of the spring  29  rests on the lower part of the thruster rocker arm  27 . The displacement of the end  30  by the worm-screw  12  permits the spring  29  to flex in such a way that it pushes on the rocker arm  27  so that it can push on the pulling pin  24  which partially enters into the slot  32  (see  FIG. 8 ) of the second clutch element  16  against its spring  25 . The action of the spring  29  is greater than that of the spring  25 .  
         [0041]     Therefore, once the pulling pin  24  is introduced into the slot  32 , the first and second elements of the clutch become connected in such a way that when one of them turns the other does so too and with that the bolt  4  for the lock  2  or  2 ′ is displaced.  
         [0042]     In the displacement from the open position at rest to open turned, the opening tension, which is created against the action of the spring  21  and of the tumbler spring of the lock  2 - 2 ′ and the actual friction of the pulling pin  24  against the walls of the slot  32 , is sufficient so that said pin  24  is not displaced outwards by the action of its spring.  
         [0043]     At the moment that the outside handle  6  ceases to be acted upon and it returns to its horizontal position, the spring  25  pushes the pin  24  so that it exits from the slot  32 .  
         [0044]     One of the important characteristics of the structure lies in the position of the arched guide  26  which is concentric with the axis of rotation of the clutch elements  15  and  16  and which is extended by an angle similar to that of rotation of the handles. In any position, including the locked position, when the pulling pin  24  is outside of the slot  32 , it has its end at all times in contact with the arched guide  26 . Therefore, the actuation operations on the handles are compact and stable operations without any variations in the resistance to overcome and without any weakened position, via a rigid and continuous guide, and not, as in the case with European patent EP0848779 mentioned earlier, a gap between the arched projection and the coupling arm and not, as in the case of patent U.S. Pat. No. 6,286,347, a large moving element which can have problems for being displaced correctly due to the transverse force components originated when the pulling pin  24  is close to the ends. The clutch element  16 , as well as the slot  32 , is connected via a cam  34  with a micro-switch  34 ′ (see  FIG. 3 ) which is in turn connected to a control system in such a way that, via it, the rotation of the handle can be detected and can be processed by computer.  
         [0045]      FIG. 4  shows the closed position, when the two locking handles are inoperable and the motor  3  is not in operation.  
         [0046]     Represented in  FIG. 5  is the closed position in which the motor  11  is not activated and in which rotation of the outside handle  6  is produced in order to open the door, which opening cannot be done because the clutch elements  15  and  16  are not connected by the pin  24  and therefore the second clutch element  16  is not displaced in order to pull on the locking bolt  4  for the lock  2 . It can be seen that the pulling pin  24  is in position and can slide with its rounded end supported on the arched guide  26 .  
         [0047]     Represented in  FIG. 6  is the rest position but in which the motor  11  has already been activated via the access control system, such as for example via the reader  13  (see  FIGS. 1 and 2 ) and the corresponding access card. In this case, by means of the motor  11  and the worm-screw  12 , the spring  29  is pushed so that the thruster rocker arm  27  can rotate and in turn push on the pulling pin  24  against its spring in order to be partially introduced inside the slot  32 . In this case, and going on now to  FIG. 7 , the turning of the outside handle  6 , due to the two clutch elements  15  and  16  being connected, causes the second clutch element  16  to be pulled on, producing the subsequent displacement of the locking bolt to its open position.  
         [0048]     Represented in  FIG. 8  is the open position because the motor  11  has been actuated as in the cases of  FIGS. 6 and 7  but here displacement has taken place of the locking bolt via the inside handle  5  and subsequently rotation of the second clutch element  16 . The rotary displacement of the thruster rocker arm  27  does not produce displacement of the pulling pin  24  because the end of the latter is flush against the cylindrical periphery of the second clutch element  16  due to the slot  32  having been displaced. Let us remember that in this position of  FIG. 8 , the inside handle  5  has been actuated.  
         [0049]     Making special mention now of  FIG. 9 , represented in it is the emergency system whose actuation causes engagement of the clutch in the event that the access control mechanism fails to work. It consists of an emergency push-rod  35  whose displacement against the spring  36  is carried out by certain means that are not represented and actuated by en emergency key which is also not represented.  
         [0050]     The end of the push-rod  35  has a special configuration by way of a lateral extension or nose in which a small depression  37  has been provided for supporting the bend end of a flexing spring  38  wound in a spiral and mounted on the stud  39  also emerging from the interior body  10 , its end  40  being extended in order to form a support in the projection  41  of the rocker arm  27 . The displacement of the thruster rocker arm  27  causes the spring  38  to flex so that its end  40  exerts pressure on the rocker arm  27  and the latter on the pulling pin  24 , forcing it to enter the slot  32  of the second clutch element, thereby achieving that both clutch elements  15  and  16  remain integral in their rotation and so displacement of the locking bolt  4  is permitted.  
         [0051]     Provision has been made for a micro-switch  42  on which the end nose of the push-rod  35  is constantly supported, in such a way that when the latter is actuated upon in an emergency operation, the micro-switch  42  opens and its signal is sent to the computing system which memorises this operation in order to check whether an emergency actuation has been effected and when said operation was effected.  
         [0052]     In  FIGS. 10 and 11  the entire clutch mechanism  1  is shown and on its front face can be seen the protective cover  9  and protective plate  43  in order to prevent vandals from drilling into clutch element  15 .  
         [0053]     Also to be seen is an adjusting nut which threads on the cylindrical part of the first clutch element  15  in order to prevent any play in the rotating shaft of the outside handle.  
         [0054]     With this arrangement presented by the clutch mechanism of the invention, various applications are permitted such as those shown in  FIGS. 1 and 2  in which the mechanism can be fitted in one position or its reverse without the different components having any functional problems on account of occupying these different positions.  
         [0055]     The rotating stop of the outside handle  6  is performed by the actual prismatic projection  22  of the first clutch element  15 , in such a way that when it rotates it acts as a stop against the projections  44  provided on one and the other side in the interior body  10 .  
         [0056]      FIG. 12  shows a longitudinal cross-section of the clutch mechanism  1  and it can be seen how the pulling pin  24  guided in the prismatic projection  22  is supported on the arched guide  26  and in the thruster rocker arm  27 , in such a way that the latter, when displaced upwards, can easily cause the said pulling pin  24  to be housed in the slot  32  of the second clutch element  16 .  
         [0057]     The control for the motor can be carried out by other means, such as for example a numeric or alphabetic key-pad or any other electronic control device. Equally, the control can be done by means of a mechanical mechanism.