Patent Publication Number: US-10767394-B2

Title: Lockable coupling device

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a lockable coupling device in particular for folding devices. 
     In folding devices with three or a greater number of folding elements arranged within a frame, one folding element that is opened first when opening the folding device is arranged pivotably on the neighboring folding element. When the first folding element is opened, for example, by approximately 90° and subsequently the neighboring second folding element is also opened, an increased load caused by the weight and leverage of the first folding element is acting on the second folding element. This can cause undesirable deformations of the second folding element which may lead to false positioning of both folding elements and also of further folding elements relative to the frame and, for example, can cause functional restrictions or loss of comfort in operating the folding device, for example, due to contacting and dragging of the bottom side of the folding elements on the floor when opening the folding elements. 
     It is therefore preferred that, prior to opening the second folding element, the first folding element is placed against the second folding element (opening angle of the first element of approximately 180°) and is secured in this position. This connection should be existing until the second folding element has reached the closed position again. 
     A coupling device that ensures this is disclosed in EP 0 342 420 B2. In this reference, a three-panel folding wall together with locking system with strictly prescribed locking sequence is described. Here, a first folding element can be pivoted against a second folding element by approximately 180° and can be fixed in this position. A mechanism prevents that the first folding element detaches from the second folding element when the second folding element is not in the closed position. Moreover, a second mechanism effects that the second folding element can be opened only once the first folding element has been secured at the second folding element. Observing this locking sequence is ensured by two different devices, and each device comprises a great number of components. This is disadvantageous in regard to production, assembly, and servicing of the device. 
     In practice, a lockable coupling devices is also known which comprises a latch whose two parts are attached to the folding elements that are to be fixed in position. In the female part of the latch, a hook that is loaded by a spring force and is rotatably supported is installed which locks the connection of the latch parts when they latch relative to each other. The hook comprises an angled lever extension which is projecting out of the female part of the latch. This projecting part acts as a sensing device that projects rearwardly past a horizontal or vertical boundary part of the second folding element. In a closed position of the second folding element, either a neighboring third folding element or the frame is pushing against the sensing device and unlocks the latching connection. A disadvantage of this device is that the sensing device can also be triggered by hand. Also, an exchange of individual parts is relatively complicated so that in case of defects usually the entire device must be exchanged. 
     The invention has the object to avoid the aforementioned disadvantages of the prior art and to provide a coupling device for a folding device with at least three folding elements that is as simple as possible and lockable, wherein the coupling device locks a releasably lockable coupling between a first folding element and a second folding element when the second folding element is not in the closed position and unlocks it when the second folding element is in the closed position. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, this is achieved by a coupling device for a folding device, in particular a glass folding device, with at least three folding elements that are arranged in particular in a frame and that each comprise two horizontal and two vertical boundary parts and are substantially planar, wherein the coupling device comprises two coupling elements that are releasably lockable with each other and are embodied as locking element and locking receptacle, wherein a first coupling element is arranged at a first folding element of the folding device and a second coupling element is arranged at a second folding element of the folding device neighboring the first folding element, wherein the first folding element is arranged pivotably about a substantially vertical axis at the second folding element in such a way that the first folding element can be pivoted toward the second folding element such that the coupling elements reach a latched position. The coupling device further comprises a locking device with a sliding element, wherein the sliding element is slidably arranged on the second coupling element substantially perpendicular to the plane of the second folding element and projects with a leading part past a leading edge of the horizontal boundary part of the second folding element that is facing the second coupling element, wherein a locking member is arranged on the leading part. The sliding element further projects with a rearward part past a rear edge of the horizontal boundary part of the second folding element that is facing away from the second coupling element, wherein the rearward part of the sliding element is supported elastically (spring action) on the side of the second folding element which is opposite the second coupling element in such a way that the rearward part, when the second folding element is not in the closed position, is located in a rest position in which the rearward part is projecting past the rearward edge. In the rest position, the locking member arranged at the leading part of the sliding element, when the two coupling elements are latched, engages lockingly a locking receptacle embodied in the first coupling element. In the rest position, the locking member is contacting a guiding contour provided at the second coupling element in such a way that unlocking of the locking member by a pulling action acting between the first and the second coupling elements is prevented. Upon closing of the second folding element, the rearward part of the sliding element is in operative contact with the frame that is acting as an abutment so that the locking member is pushed along the guiding contour out of the locking receptacle and releases the locking action of the locking device. 
     Thus, a first coupling element that is arranged at the first folding element and a second coupling element that is arranged at the second folding element provide a releasably lockable coupling. The coupling elements can be embodied so as to be complementary to each other as a male latching part and a female latching receptacle. Preferably, the first coupling element is a male latching part and the second coupling element is a female latching receptacle. Preferably, the coupling elements are screwed to the respective folding elements or are locked by a snap-on action to the frame sections of the folding elements. 
     In addition, the coupling device comprises a locking device that automatically locks the coupling elements when they are latched to each other when the second folding element is not in the closed position (i.e., the rest position of the second folding element) and, on the other hand, cancels this locking action as soon as the second folding element reaches the closed position. This preferably monolithically formed locking device is associated with the second coupling element and a horizontal boundary part (usually the frame section) of the second folding element. The locking device projects in this context past a leading edge of the upper boundary part of the second folding element which is facing the second coupling element and also projects past a rearward edge of the upper boundary part of the second folding element which is facing away from the second coupling element. 
     The rearward part of the locking device forms a sensing device which is elastically supported on the side of the folding element which is facing away from the second coupling element; the abutment of the sensing device is the frame in which the folding elements are mounted. Preferably, a region of the rearward part of the locking device is embodied as a leaf spring. In a substantially unclosed position of the second folding device, the springy part of the locking device is in the unstressed state (rest position), wherein the rearward part of the locking device projects past the rearward edge. 
     The locking device is supported slidably on the second coupling element in a direction that is substantially perpendicular to the plane of the folding element. Preferably, this is achieved by a projection which is formed on the second coupling element and a slot which is complementarily embodied in the locking device. The projection has preferably moreover a widened portion which is projecting past the slot and substantially blocks a movement of the locking device in vertical direction. For simplifying the assembly, the guide slot has a mounting opening that is wider than the widened portion of the projection. The mounting opening is furthermore preferably not arranged in an area of the guide slot which in the finish-mounted operating state of the locking device is in operative connection with the projection. 
     The leading part of the locking device comprises a region which in the unstressed rest position of the locking device lockingly engages the first coupling element upon latching of the two coupling elements. Preferably, the first coupling element in this context has a locking receptacle (recess) in the locking member that can be engaged by the leading part of the locking device. When a force is applied for opening the coupling, even though the second folding element is not closed, for example, by pulling the first folding element and thus the first coupling element in a direction opposite to the second coupling element, a guiding contour which is formed in the second coupling element and is in contact with the leading part of the locking device blocks a movement of the locking device. This is preferably achieved in that the leading part of the locking device engages the recess and acts like a barb to block the guiding contour against removal of the barb in case of the described pulling action. The locking engagement of the leading part of the locking device is maintained. 
     When upon closing of the second folding element the rearward part of the locking device comes into operative contact with the frame of the folding device, the guiding contour which is embodied in the second coupling element guides the leading part of the locking device out of the locked position. When pushing in the rearward part of the locking device toward the guiding contour, the guiding contour extends in such a way that the leading part is guided across it out of the locked position. Preferably, the guiding contour is designed as an incline (ramp) and the leading part of the locking device is embodied in a wedge shape. The locking device can be manufactured as a stamped or bent part in particular of spring steel. In a preferred embodiment, the locking element is substantially a flat stamped part of sheet metal which is angled at the rear and front. 
     In a further embodiment, the locking device is comprised of two parts, a locking member and a sliding element that moves the locking member. In this context, the leading part of the sliding element can engage a recess of the locking member. 
     A coupling device according to the invention that can be comprised of only three or four individual parts has particular advantages in regard to manufacture, assembly, and servicing. Moreover, the coupling device according to the invention can be retrofitted with minimal expenditure practically on any type of folding device. In addition, the opening mechanism of the locking device is substantially inaccessible so that a faulty operation can be substantially completely precluded. 
     Further advantages and details result from the claims and the illustrated embodiments which will be explained in the following. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIGS. 1 a  to 1 c    show schematically a folding device in closed position ( FIG. 1 a   ), partially open position ( FIG. 1 b   ), and open position ( FIG. 1 c   ). 
         FIGS. 2 a  to 2 c    show enlarged details of  FIGS. 1 a  to 1 c   , respectively. 
         FIG. 3  shows the coupling device according to the invention in a perspective view. 
         FIGS. 4 a  to 4 c    shows the coupling device of  FIG. 3  in plan view ( FIG. 4 a   ) in side view ( FIG. 4 b   ), and section view ( FIG. 4 c   ). 
         FIGS. 5 a  to 5 c    show views in accordance with  FIGS. 4 a  to 4 c    of the coupling device in unlocked position. 
         FIGS. 6 a  to 6 c    show another embodiment of the coupling device in an illustration according to  FIGS. 4 a    to  4   c.    
         FIGS. 7 a  to 7 c    shows the coupling device of  FIGS. 6 a  to 6 c    in unlocked position. 
         FIG. 8  illustrates the installation situation of the coupling device as shown in  FIG. 6   b.    
         FIG. 9  illustrates the installation situation of the coupling device as shown in  FIG. 7   b.    
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Individual technical features of the embodiments described in the following can also be combined with the afore described embodiments as well as the features of the independent claims and further claims to subject matter in accordance with the invention. 
     Elements that functionally are acting at least partially in same way are identified with identical reference characters. 
       FIGS. 1 a  to 1 c    show a folding device with three folding elements  1 ,  2 ,  3  secured in a frame  4 . The frame  4  however must not be embodied as a separate peripheral component but can also be embodied, for example, by surrounding wall or building areas, for example, when required guiding sections are embedded therein. The left folding element  1  in the illustration is designed as a rotary panel and the folding device opens, as symbolized in  FIG. 1 a    by the arrows.  FIG. 1 b    shows all three folding elements  1 ,  2 ,  3  of the device in partially open position in order to indicate their movement directions wherein it is precisely the position of the rotary panel  1  illustrated in  FIG. 1 b    that is to be avoided by the coupling device in accordance with the invention. In  FIG. 1 c   , the folding device is in completely open position in which the folding elements  1 ,  2 ,  3  with their boundary parts  5  are almost contacting each other. In the illustrated embodiment, the boundary parts  5  are panel frame sections of the folding elements  1 ,  2 ,  3  that carry glass elements (glass panes). However, in case of frameless panels, the boundary parts  5  can also be the edges of the glass elements. 
       FIG. 2  shows in detail the upper left edge of the folding device with a first coupling element  10  arranged on the rotary panel  1  and a second coupling element  20  which is arranged on the directly neighboring folding element  2 . For opening the folding device, first the rotary panel  1  is rotated about axis A and placed against the second folding element  2 . In doing so, the coupling elements  10  and  20  latch with each other (see  FIG. 2 b   ) so that this position of the folding elements  1 ,  2  is maintained even when the folding device is opened farther, as indicated in  FIG. 2 c   . The configuration and function of the coupling device according to the invention will be explained in the following with the aid of  FIGS. 3, 4   a - 4   c ,  5   a - 5   c ,  6   a - 6   c ,  7   a - 7   c ,  8 , and  9 . 
     The coupling device is comprised substantially of the first coupling element  10 , the second coupling element  20 , and a locking device  30  which prevents separation of the coupling elements  10 ,  20  when the second folding element  2  is open. The first coupling element  10  in the embodiment is designed as a locking member and the second coupling element  20  is embodied as a corresponding locking receptacle which comprises a recess  21  surrounded by two springy locking tongues  22 . The coupling elements  10 ,  20  form a latch device that is secured (locked) by the locking device  30  in the connected latched position ( FIGS. 3 and 4   a - 4   c ) or, for disengagement of the coupling elements  10 ,  20  ( FIGS. 5 a -5 c   ), can be released (unlocked). In the first embodiment ( FIGS. 3, 4   a - 4   c ,  5   a - 5   c ), the locking device  30  comprises a sliding element  31  with a locking member  32 . The locking member  32  engages in the locked position ( FIGS. 3 and 4   a - 4   c ) a locking receptacle  11  formed in the first coupling element  10  so as to lock the coupling elements  10 ,  20 . The rearward part of the sliding element  31  projects past a rearward edge  5 ′ of the horizontal boundary part  5  of the folding element  2  to which the second coupling element  20  is connected; this rearward part is elastically supported against the rearward side  2 ′ of the folding element  2  which is positioned opposite the coupling element  20  (see  FIG. 4 b   ). In the illustrated embodiment, this is realized in a preferred way in that the rearward part of the sliding element  31  itself is designed as a leaf spring  33 . The sliding element  31  can be produced as a stamped bent part, preferably of sheet metal; such an embodiment is particularly preferred, simplifies production, and is inexpensive. As can be seen in  FIGS. 3, 4   a - 4   c , and  5   a - 5   c , even a monolithic configuration of the sliding element  31  together with the locking member  32  at the front end that is bent in a hook shape is possible. 
     While the locking device  30  in  FIGS. 3 and 4   a - 4   c  is illustrated in a locked rest position in which the leaf spring  33  is unstressed,  FIGS. 5 a -5 c    show a disengaged or unlocked position. Here, the second folding element  2  is closed so that the rearward part of the sliding element  31 , here the leaf spring  33 , is in operative contact with an abutment W which is formed by the frame  4  of the folding device. The leaf spring  33  is compressed so that the sliding element  31 , in a movement direction S perpendicular to the plane E of the second folding element  2 , is moved toward the first folding element  1 . A guiding contour  23  is provided in the second coupling element  20 , in the illustrated embodiment provided at its upper locking tongue  22 , and pushes the locking member  32  out of the locking receptacle  11  so that the locking device  30  is disengaged (unlocked). In order to prevent that a simple pulling action acting on the rotary panel  1  or on the first coupling element  10  causes release of the locking device  30 , the locking member  32  is designed as a hook in the illustrated embodiment and the locking receptacle (recess)  11  is provided with a projection  12  acting as a “barb”. 
     The sliding element  31  is secured on the second coupling element  20  in a constructively simple but effective way in that the sliding element  31  comprises a slot-like cutout  34 ; an upwardly extending projection  24  of the second coupling element  20  passes through this cutout  34  and in this way guides the movements in the sliding direction S of the sliding element  31 . In order to prevent that the sliding element  31  accidentally is released in upward direction from the coupling element  20 , the projection  24  has preferably laterally widened portion  24 ′ wider than the relevant parts of the slot-type cutout  34  so that the coupling device according to the invention can be installed not only at the top side of the folding elements but, if desired, also at the bottom side. For simplified assembly of the sliding element  31  on the coupling element  20  itself, in such an embodiment the slot-type cutout  34  of the sliding element  31  is provided with a mounting opening  35  which is greater than the widened portion  24 ′ of the projection  24 . 
       FIGS. 6 a -6 c  and 7 a -7 c    show a modified embodiment of the coupling device according to the invention in illustrations which correspond to those of  FIGS. 4 a -4 c  and 5 a -5 c   . The modification concerns only the configuration of the locking member  32  which is a separate component in the embodiment of  FIGS. 6 a -6 c  and 7 a -7 c   . The locking member  32  is of a wedge-shaped configuration and can glide with its slanted bottom side along a guiding contour  23  which forms a guiding ramp. For securing the locking member  32  on the sliding member  31 , the leading part of the sliding element  31  is angled and is inserted into a receptacle  32 ′ of the locking member  32 . When this receptacle  32 ′ as illustrated is provided with sufficient clearance, the leading part of the sliding element  31  is not subjected to a bending load even when being unlocked ( FIGS. 7 a -7 c   ); and this can increase the service life of the locking device. 
       FIGS. 8 and 9  show finally only the second coupling element  20  of the embodiment of  FIGS. 6 a -6 c  and 7 a -7 c    in an installation situation. In  FIG. 8 , the folding element  2  which carries the coupling element  20  is not completely closed so that the leaf spring  33  of the sliding element  31  at the rear does not contact an abutment. In  FIG. 9 , on the other hand, the leaf spring  33  is compressed by the seal  40  of the frame  4  which forms the abutment so that the sliding element  31  is pushed in the direction S forwardly and moves the locking member  32  in forward/upward direction so as to disengage (unlock) the locking device  30 . 
     The coupling device according to the invention can be embodied in a simple way and comprised of only three components ( FIGS. 3, 4   a - 4   c ,  5   a - 5   c ) or four components ( FIGS. 6 a -6 c , 7 a -7 c   ) but is effective despite the simple configuration Individual components in a service situation can be exchanged in a simple way; also, the entire device can be retrofitted. It can be screwed onto folding elements  1 ,  2  (see receptacles  6  in  FIG. 3  provided for fastening elements) but can also be embodied to be adhesively connected or to be inserted into profiled sections of the boundary parts  5  of folding elements. 
     The specification incorporates by reference the entire disclosure of German priority document 10 2017 100 742.3 having a filing date of Jan. 16, 2017. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.