Patent Publication Number: US-6705141-B1

Title: Combined mechanical and electronic key, in particular for the locks of motor vehicles

Description:
The invention pertains to a combination key of the type indicated in the introductory clause of claim 1. A key of this type makes it possible to actuate locks directly in a mechanical manner but also, either alternatively or supplementally, to actuate them electronically, e.g., to actuate the particular lock in question or other locks from a remote location. The key container itself represents the means by which the key is actuated both mechanically and electrically. For the purpose of electronic actuation, therefore, the key container has actuating points on its outside surface in the form of, for example, electrical push buttons or resilient membranes, which act on electrical switches or the like provided inside the container. The flat mechanical key has the shape of an “L” and is supported by one of the sidepieces of the L on the forward end of the container with freedom to pivot, for which reason this sidepiece is referred to below as the “support sidepiece”. When the flat key is in its home position, the other sidepiece of the L, which forms the shaft of the key, is inside the container, into which it has been pivoted. This sidepiece of the L is referred to in the following as the “shaft sidepiece”. The shaft sidepiece of the flat key can be pivoted out of the container and into the working position. To hold the flat key securely in place, it is recommended that it be latched in the key container when in either of its two positions. 
     In the case of the known key of the type indicated in the introductory clause of claim 1 (EP 0 267 429), the L-shaped flat key with its two sidepieces consists of two parts; it has a top piece in the form of a support ring with a tangential projection, into which the end of a blade can be inserted and to which the blade is detachably connected. The inserted connecting piece of the blade must be secured by a screw or a rivet after insertion. This is laborious and time-consuming. The L-sidepiece forming the shaft sidepiece of the known flat key comprises the support ring, the projection, and the inserted blade. The shaft sidepiece is therefore formed out of two parts. The transition area between the inserted blade and the projection on the support ring is subject to breakage. To prevent it from breaking, the material in the projection of the ring enclosing the receiving slot for the blade must be made as thick as possible, which leads in the direction away from the goal, which is to obtain a space-saving key. 
     In another known key (DE 39 02 537 C2), a mechanical push button is provided in the area of the pivot axis of the flat key; this button is spring-supported in both the axial and radial directions. The push button serves as a pivot axis for the flat key. The double spring support of the push button has two tasks to perform for the flat key. One of these tasks is to spring-load the flat key so as to pivot it out of its home position and into its working position. The other task is to latch the key as securely as possible in either one of its two pivot positions. For this purpose, the push button requires suitable contours, and the flat key requires suitable counter contours. Although the flat key is designed with the shape of an “L”, the support sidepiece must, because it carries the counter profiles, be of considerable thickness, and it is therefore prefabricated separately as a support body with a rectangular profile. So that the considerable thickness of the support body can be utilized, the shaft sidepiece is located on a plane parallel to the pivot axis of the flat key. This means in turn that the key container must has a corresponding thickness. The support body of the flat key serving to hold the mechanical push button has a slot for the subsequent attachment of the key shaft, which is fabricated separately. The key shaft is inserted into a slot in the support body and secured in place there by a pin or the like. This process is time-consuming and expensive. 
     There are also combination keys (DE 22 26 385 A and DE 38 42 790 C1), which, although they comprise a flat, L-shaped key, nevertheless do not have a push button in the area of the axis. An immovable bearing pin serves as the pivot axis. Because no counter profile is required for a push button, the support sidepiece of the flat profile serving as a support for the pivoting movement can be flat. The flat key is designed as a flat plate, in-which the flat profile of the shaft sidepiece also lies. This key housing can be built flatter, but there is no spring-loading to move the shaft sidepiece out of a rest position, recessed in the key container, into the outward-pivoted working position. This makes the key difficult to manipulate. In addition, there is no space-saving way to latch the flat key in these two positions in the container. The inability to secure the flat key in its pivoted positions leads to problems both when the key is carried in the user&#39;s pocket and also when it is used, e.g., when the key housing is turned to operate the lock. 
     When it is desired to fasten a component to a sheet-metal section with a screw, it is known that, to obtain the required depth for the screwing-in of the screw, the depth of the female thread in the sheet-metal section can be increased by an adapter or a riveted insert (U. Richter, R. v. Voss, and F. Kozer:  Bauelemente der Feinmechanik [Structural Elements in Precision Mechanics ], Berlin, Verlag Technik, 1954, p. 137). This way of providing female threads in sheet-metal sections is incompatible with the concept of a flat key. The publication cited does not provide any suggestions concerning the design of flat, L-shaped keys. 
     The invention is based on the task of developing a reliable, space-saving key of the type indicated in the introductory clause of claim 1, which can be produced more easily and at lower cost. This is accomplished according to the invention by means of the measures listed in the characterizing clause of claim 1, to which the following particular meaning belongs: 
     In the invention, the key with the two sidepieces of its L shape is designed as a single unit in the form of a flat plate. The L-shaped flat key can be stamped out of plate material. As a result of this one-piece design, a strong, unbreakable transition area is obtained between the support sidepiece and the shaft sidepiece. In spite of the flat design of this L-shaped key, the mechanical push button in the key container can still be installed in the area of the support sidepiece. This is possible because the counter profiles required in and of themselves for the push button are left to an insert, which is mounted nonrotatably in an opening in the plate of the bearing sidepiece The insert serves to provide both pivoting support and, advisably, axial guidance for the push button; the insert also serves to accept the spring for the push button. As a result, the design of the key container is simplified as well. In spite of the one-piece, inexpensive L-shape of the flat key, the key can still be latched securely in both its home and working positions via the push button. In addition, when, in the home position, the latching function is deactivated by pushing the push button, the key is pivoted automatically from its home position to the working position by the elastic force acting on it by way of the driver surfaces provided on the push button and on the insert. 
    
    
     Additional measures and advantages of the invention can be derived from the subclaims, from the following description, and from the drawings. An exemplary embodiment of the invention is illustrated schematically in the drawings: 
     FIG. 1 shows a perspective view of the key container, from which mechanical flat key projects; 
     FIG. 2 shows another perspective view, this time of a plug-in unit belonging to the flat key of FIG. 1, consisting of an electronic capsule enclosing the electronic components; 
     FIG. 3 shows a combination housing, assembled from the key container of FIG.  1  and the plug-in unit of FIG. 2, which is used to manipulate the key during the mechanical and electronic actuating processes; 
     FIG. 4 shows an exploded view of some of the essential parts of the key container shown in FIG. 1, along with the mechanical flat key, before the parts have been assembled; 
     FIG. 5 shows an exploded view of the two components of the mechanical flat key before they are combined; 
     FIG. 6 shows a cross section through the component of FIG. 5 along the cross-sectional line VI—VI shown there; 
     FIG. 7 shows a cross section through the assembled key container of FIG. 1 along the cross-sectional line VII—VII shown there, where the push button is seen in its pushed-in position; 
     FIG. 8 shows an axial cross section through the key container shown in FIG. 1 along the cross-sectional line VIII—VIII shown there; and 
     FIG. 9 shows a cross section through the combination housing shown in FIG. 3 along the cross-sectional line IX—IX shown there. 
    
    
     The combination key according to the invention allows both the mechanical and the electronic actuation of a lock (not shown). It consists of two parts  10 ,  20 , each prefabricated separately, which are then inserted into each other. The one part  10  comprises the mechanical closing means and consists of a key container  10 , the components of which can be seen most easily in the exploded diagram of FIG.  4 . The other part  20  is a plug-in unit, to be described in greater detail below, which holds in its interior the electronic components  40 , indicated in cross section in FIG.  9 . 
     As can be seen on the basis of FIGS. 1 and 4, the mechanical part comprises, first, a two-shell key container  10 . Whereas the upper shell  11 , as can be seen in FIGS. 7 and 8, is designed as a flat plate with connecting projections  13  at various points on its inside surface, the lower shell  12  comprises side walls  14  and a bottom part  15 . Connecting sockets  16  for the previously mentioned connecting projections  13  on the upper shell  11  are located at various points in the side walls  14 . The upper shell  11  extends only over the front end of the key container  10  and has at the rear an open area  17 , which creates an empty space accessible from the outside and leading toward the interior  18  of the shell. This is important for the insertion and removal of the plug-in unit  20  to be described in greater detail below. 
     The key container  10  also includes, as FIG. 4 shows, a mechanical flat key  30 , which is installed with freedom of movement, so that it can be moved from a recessed, home position in the container  10  (not shown) into a working position, projecting from the container, as shown in FIGS. 1-4. The flat key  30  is made of metal. Although other types of movement could also be imagined, this flat key  30  is free to pivot around the pivot axis  33 , indicated in broken line in FIGS. 1,  3 , and  4 . The flat key  30  is made as a stamping from a flat plate  34 , illustrated in broken line in FIG. 4; the stamping has an L-shaped outline with two sidepieces  31 ,  32 . One of the sidepieces of the L is short and serves to support the flat key  30  at the front end of the key container so that the key can pivot and is therefore referred to in short below as the “support sidepiece”. The other sidepiece  32  of the L comprises the actual flat profile of the key shaft, for which reason it is referred to in the following as the “shaft sidepiece”. These two sidepieces  31 ,  32  therefore lie in a common plane, determined by the previously mentioned plate  34 ; in the final assembled state of the key container  10 , this plane is perpendicular to the pivot axis  33 . As can be seen in FIG. 5, the support sidepiece  31  is provided with a noncircular plate opening  35 , which serves to hold a separate insert  36 . 
     The push button  40  is spring-loaded both in the axial and in the radial direction and has profiles  19 ,  48 ,  28  designed to be in agreement with those of the container  10 . The insert  36  consists of relatively resilient material, preferably plastic, and has a special counter profile  37 ,  38 ,  39  for a push button  40 , which determines the position of the pivot axis  33 . The spring action is exerted by a combination compression-torsion spring  41 , which, as can be seen in FIG. 7, is held in an axial bore  45  in the push button  40 . The spring  41  is attached nonrotatably by its one end  42  to the push button  40 , whereas the other end  43  of the spring is attached to the lower shell  12  of the container  10 . The spring  41  is helical in design. During the assembly process, a mandrel  44 , seated on the inside surface of the bottom of the lower shell  12 , projects into the interior of the spiral and also into the insert  36 . 
     According to FIG. 5, the flat key  30  and its plate opening  35  are first produced by stamping, and then the insert  36  is inserted vertically into the plate opening  35 . After insertion, the insert projects beyond the two flat surfaces of the flat key, as FIGS. 4 and 7 show. In addition, the insert also has cylindrical projections  47 , shown in FIG. 6, and stop pins  39 , extending from each of the two flat sides and projecting into ring-shaped groove segments  19  in the two shells  11  and  12 , as can be seen in FIG.  8 . When the stop pin  39  is in the position shown in solid line in FIG. 8, the key is in the previously mentioned working position, after it has been pivoted out of the container  10 . Then the previously described shaft sidepiece  32  of the flat key  30  extends in the direction of the auxiliary line  30 . 1  indicated in broken line in FIG. 8, which characterizes the working position of the flat key  30  illustrated in the other figures. In this working position  30 . 1 , the flat key is latched by the push button  40 . Then driver wings  48 , arranged diametrically in the present case on the push button  40 , engage in associated radial grooves  28  in the inside surface of the upper shell  11  and thus secure the flat key  30  in its outward-pivoted position. 
     Axial grooves  48  in the insert  36  serve as counter profiles for the driver wings  48 ; these grooves allow an inward-pushing movement in the direction of the force arrow.  46  shown in FIG.  7 . This inward movement  46 , which has been completed in FIG. 7, pushes the push button  40  into its lowered position, as a result of which the driver wings  48  become disengaged from the radial grooves  28 . The inward movement  46  takes place against the axial force of the spring  41 . The latching of the working position  30 . 1  is then released. The flat key can then be swung back into its home position in the housing in the direction of the motion arrow  29  of FIG. 8 against the torsional force of the spring  41 , illustrated by the force arrow  49  in FIG.  8 . Then the shaft sidepiece  32  of the flat key  30  lies on the broken line indicated by the number  30 . 2 , as seen in FIG.  8 . In this home position  30 . 2 , the shaft sidepiece  32  has disappeared in the lateral gap  24 , which can be seen in FIG. 3, of the overall housing  50 , to be described in greater detail below, which is formed out of the key container  10  and the plug-in unit  20 , which has been inserted into the container. Then the driver wings  48  are again in axial alignment with the radial grooves  28  in the housing; they snap into the grooves under the restoring force of the spring  41  and thus also latch the flat key in this home position  30 . 2  in the key container  10 . 
     The push button  40  also serves as a pivot bearing for the pivoting movement  29 . For this purpose, a bearing bore  25  is provided in the upper shell  11  of the container  10 , as can be seen in FIG.  4 . This bore is in axial alignment with an axial bore  37  in the insert  36  shown in FIGS. 5 and 6 and with the previously mentioned mandrel  44  on the lower shell  12 . The push button  40  determines the pivot axis  33  of the flat key  30 . The stop pin  39  on the insert on one side and the ring-shaped groove segment  19  assigned to it on the housing side can also take over rotational guide functions during the pivoting movement  29 . In addition, rotational stops can also be realized by the outline profile of the key  30  on the one side and inside surfaces on the two shells  11 ,  12  on other. 
     Instead of prefabricating the insert  36 , it would also be possible to postfabricate the insert  36  by an injection-molding technique. For this purpose, the described flat key  30  is introduced into an injection mold, in which the insert  36  is then formed in the plate opening  35  by casting. The counter profiling  37 ,  38 ,  39 ,  47  mentioned above is then present again in the same form. 
     In many applications, a so-called transponder  26  is also desirable in the case of the above-mentioned combination key for electronic actuation. This transponder  26  is intended to individualize the combination key electronically right from the start. When the key is inserted into the associated lock, a communications process take place between the transponder  26  and the lock; if it is found that the lock and the key belong together, the lock functions are initiated immediately. For this reason, transponders  26  of this type are installed in the forward area of the key container  10  in the invention. For this purpose, the lower shell  12  has a chamber  27 , into which the transponder(s)  26  can be cemented. Because an electronic power supply is not required for the transponder  26 , the final assembled key container  10  of FIG. 1 does not need to be separated into its shells  11 ,  12  so that the battery can be replaced, etc. The transponders  26  are therefore protected permanently in their chamber  27 . This also applies to the previously mentioned additional electronic components  21 , which form an internal part of the previously mentioned detachable plug-in unit  20  of the overall housing  50 . 
     As can best be seen in FIG. 9, a housing-like capsule  22 , in the interior  23  of which the components  21  are mounted and thus closed off on all sides from the outside, belongs to the plug-in unit  20 . The wiring of the components and possibly the electrical interference can be provided in the interior  23  of the capsule. This structural unit  21 ,  22 , which can be plugged into the key container  10 , is prefabricated as a complete unit and is called the “electrocapsule” in the following. For assembly purposes, the key container  10  is shaped to accommodate it as follows: 
     The previously mentioned open area  17  of the key container  10  is produced simply by allowing the upper shell  11 , as seen in FIG. 1, to cover only the forward section  51  of the key container  10 . As a result, an open area accessible from the outside and leading to the interior  18  of the shell is created. This open area  17  has not only an upper opening  52  facing upward but also a side opening  53 , accessible from the rear  54 . This side opening arises because not only the rear section of the upper shell  11  is missing but also, as FIG. 1 shows, the side wall  14  of the lower shell  12  has been omitted at the rear  54  of the container  10 . The electrocapsule  20  is pushed through this side opening  53  into the open area  17  of the key container  10  in the direction of the motion arrow  55  of FIG.  1 . In its plugged-in position according to FIG. 3, the electrocapsule  20  seals off the upper opening  52 . The plug-in movement  55  is on a plane parallel to the above-mentioned pivoting movement  29 . The following guide means  61 ,  62  are provided to guide the insertion and sliding-in movement  55  of the electrocapsule  20 . 
     On the interior surface of the bottom  15  of the lower shell  12 , there are two parallel guide strips  61 , which extend toward the side opening  53 . They are undercut and have preferably a dovetail profile. To these strips are assigned complementary guide grooves  62  in the bottom surface of the housing of the electrocapsule  20 . The engagement between these guide means  61 ,  62  can be seen in the cross section of FIG.  9 . One of the long sides of the capsule housing  22  according to FIG. 9 has a step at  58 , so that, together with a corresponding step  59  in the lower shell  12  according to FIG. 4, the lateral gap  24  for the shaft sidepiece  32  of the flat key  30  is created when the capsule is inserted. In the inserted position according to FIGS. 3 and 9, the external surfaces of the electrocapsule  20  which remain visible on the one side and the external surfaces of the key container  10  which remain visible on the other form a flush transition with each other. The two parts  10 ,  20  form then the previously mentioned combination housing  50 ; during the manipulation of the key, the two parts are gripped jointly by the hand. The combination of the two is therefore called the “combination housing”. This applies both to the mechanical actuation of the associated lock, when the outward-pivoted shaft sidepiece  32  is turned by means of the combination housing  50 , and also to the electronic actuation. For this purpose, actuating points  60  are provided in the common combination housing  50  on the still-visible outside surface of the electrocapsule  20 . These can take the form of push button switches or membrane actuating points. These actuation sites can be provided with additional membrane-like covers in the area of the previously mentioned push button  40 , to which the following special meaning belongs: 
     The insertion position of the electrocapsule  20  in the key container  10  shown in FIGS. 3 and 9 is not only limited by stop means but also secured by latching means. This latching function can also be taken over advantageously by the push button  40 . For this purpose, the electrocapsule  20 , according to FIG. 2, is extended at the front by a tab  56 , which, when in the inserted position of FIG. 3, covers the remaining forward section  51  of the upper shell  11  of the key container  10 . The tab  56  has an opening  57 , into which the axially spring-loaded push button  40  snaps when the electrocapsule  20  according to FIG. 3 is plugged into position. As a result, it is ensured that the key container and the electrocapsule  20  will be held securely together. The opening  57  passes through the tab  56 , for which reason, after the parts have engaged as shown in FIG. 3, a longitudinal piece of the push button  40  sufficient for actuation projects out from the tab  56 . To disassemble the combination housing  50  into its component parts  10 ,  20 , the push button  40 , as shown in FIG. 7, is pushed in the direction of arrow  46  until it disengages from the opening  57  in the tab  56 . 
     The push button  40  can be covered by a membrane in the area of the tab  56 , which membrane functions in the same way as for the actuating points  61 . These membranes of the actuating points  61  can be combined with the previously mentioned membrane in the area of the push button. 
     List of Reference Numbers 
       10  first key part, key container 
       11  upper shell of  10   
       12  lower shell of  10   
       13  connecting projection on  11   
       14  side wall of  12   
       15  bottom of  12   
       16  connecting receptacle in  12   
       17  open area of  11 , free space in  18   
       18  interior of shell 
       19  profile in  11 ,  12  for  39 , ring-shaped segment 
       20  second part of key, plug-in unit, electrocapsule 
       21  electronic component 
       22  housing-like capsule for  21   
       23  interior of capsule for  22  in  21   
       24  lateral gap in  50  for  32  (FIGS. 3,  9 ) 
       25  bearing bore in  11  for  40  (FIG. 4) 
       26  transponder 
       27  recess in  11  for  26  (FIG. 4) 
       28  profile in  11  for  48  of  40 , radial groove (FIG. 7) 
       29  pivoting movement arrow for  30  (FIG. 8) 
       30  mechanical flat key for  10 , stamping 
       30 . 1  working position of  32  (FIG. 8) 
       30 . 2  home position of  32  (FIG. 8) 
       31  first L-sidepiece of  30 , support sidepiece 
       32  second L-sidepiece of  30 , shaft sidepiece 
       33  pivot axis for  30   
       34  flat plate for  30   
       35  plate opening 
       36  insert in  35   
       37  counter profile in  36 , axial bore (FIGS. 5,  6 ) 
       38  counter profile of  36 , axial groove in  36  for  48  (FIGS. 5,  8 ) 
       39  counter profile of  36 , guide or stop pin (FIGS. 5,  6 ) 
       40  push button 
       41  compression-torsion spring for  40   
       42  first end of spring  41  (FIG. 7) 
       43  second end of spring  41  (FIG. 7) 
       44  mandrel on  12  for  41  (FIG. 4) 
       45  axial bore in  40  for  41   
       46  arrow of the pushing-in movement of  40  (FIG. 7) 
       47  counter profile on  36 , cylindrical shoulder on  36  (FIG. 5) 
       48  profile, driver wing on  40   
       49  arrow of the outward-pivoting force of  41  for  30  (FIG. 8) 
       50  overall housing consisting of  10 ,  20 , combination housing 
       51  forward section of  10   
       52  upper opening of  10  at  17  (FIG. 1) 
       53  side opening in  11  (FIG. 1) 
       54  rear of  10   
       55  arrow of the insertion movement of  20  into  10  (FIG. 1) 
       56  tab on  20  (FIG. 2) 
       57  opening in  56  for  40  (FIG. 2) 
       58  inside step on  22  for  24  (FIGS. 2,  9 ) 
       59  step on  12  for  24  (FIG. 4) 
       60  actuating point on  20  (FIG. 1) 
       61  guide means on  12 , guide strip 
       62  guide means on  20 , guide groove