Patent Publication Number: US-9845620-B2

Title: Deadbolt indicator

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/938,108, filed on Feb. 10, 2014, and entitled “Deadbolt Indicator,” which application is hereby incorporated by reference. 
    
    
     FIELD OF INVENTION 
     This invention relates generally to cylindrical deadbolt assemblies and, more particularly, to providing a visible indication of whether a deadbolt is locked or unlocked. 
     BACKGROUND 
     There are two predominant categories of locks: cylindrical locks and mortise locks. Mortise locks were the first type of locksets to be mass produced. A mortise lock comprises a lock box body full of cams and levers. It is expensive to produce. Furthermore, to install a mortise lock, a large amount of material must be cut out of the edge of the door to accept the lock body. This requires special tools and a high skill level. 
     Early in the twentieth century, Dexter Locks™ introduced a new type of lock that had less complex parts. To mill a door to accept the lock required only drilling a cylindrical hole through the face of the door and drilling another hole from the edge intersecting with the face hole. Since the required preps were cylindrical holes, these locks were called cylindrical locks. From the time of their introduction, the cylindrical lock rapidly grew in popularity. Because of the lower manufacturing cost and sales prices and ease of installation, they became the most popular lock type used. Currently 99 percent of the locks sold in the United States, both in the commercial and residential market, are cylindrical locks. 
     Deadbolt locks come in both mortise and cylindrical varieties, with the vast majority being cylindrical. There are two basic types of cylindrical deadbolt: the single cylinder deadbolt and the double cylinder deadbolt. The single cylinder deadbolt has a key on the outside and a thumb turn on the inside. A double cylinder deadbolt has a cylinder on both sides and requires a key to lock or unlock the deadbolt from either side of the door. 
     Contemporary building and fire codes do not allow cylinder deadbolts on doors in a path of egress (the path of exit) unless the locking device is readily distinguishable as locked and a readily visible, durable sign is posted on the egress side on or adjacent to the door stating: “THIS DOOR TO REMAIN UNLOCKED WHEN BUILDING IS OCCUPIED.” 
     The predominant indicator available in the market today is the Adams Rite™ indicator. However, it only works in conjunction with mortise locks. The use of the Adams Rite™ indicator requires special milling and mortising of a door that is not common in either the residential or the commercial door marketplace. 
     Applicant is unaware of any indicator deadbolt that fits the code requirements and fits the most common lock prep, the cylindrical lock. If a door has been machined for a cylindrical lock, then the Adams Rite™ lock cannot be installed without great expense or rework to the door. So, if a door has been machined for a cylindrical deadbolt and is in the path of egress, there are currently no locks or solutions that will allow the door owner to meet the egress codes without encountering great expense. 
     Contractors frequently fail their final fire inspection for having a deadbolt that does not meet the code requirements for lack of an indicator. They are faced with replacing the door or having it patched and remachined for the Adams Rite™ indicator or simply removing the deadbolt. In most cases the deadbolt was installed because the added security was needed. Removal opens up the end user to more liability and possible theft. The most common resolution to this dilemma is for the contractor to remove the deadbolt and put a filler plate into the hole left by the deadbolt. They pass their inspection and tell the owner they are not allowed to have a deadbolt on the door by code, but if they want it they can install it themselves when the contractor is done with the project. Frequently, the building owner will reinstall the deadbolt even though it is in violation of life safety codes and is unsafe. 
     SUMMARY 
     Indicators are provided for a cylindrical cylinder deadbolt. In one embodiment, the indicator fits the industry standard cylindrical lock prep and does not require any extra machining of the door. The indicator works via a cam inside that shares the cam on the back of the cylinder and turns as the key is turned on the deadbolt. The cam turns a dial that is marked LOCKED or OPEN, IN USE or OPEN, or with some other suitable indications. 
     In another embodiment, the indicator is built into the deadbolt itself, with the holes and LOCKED or OPEN showing on the housing body of the deadbolt. 
     In yet another embodiment, an indicator is provided for a single cylinder deadbolt that is not on an exit door. For instance, the indicator may be used on a single stall bathroom door with a single cylinder deadbolt that has a thumb turn on the inside and a cylinder on the outside. This shows the occupied status of a room. Unlike privacy indicator deadbolts available for bathrooms, this apparatus locks from the outside of the room. Also, unlike typical privacy indicator deadbolts that only require a flat object such as a bobby pin to unlock from the secure side, this apparatus prevents unlocking of the deadbolt from the secure side without a key. Installed on a single stall restroom with push pulls, the apparatus acts as a securing device for privacy, but also allows the owners to lock down the restroom when they do not want to allow access because of needed repair or cleaning. 
     These and other objects, features, and advantages of the present invention will be readily apparent to those skilled in the art from the following detailed description taken in conjunction with the annexed sheets of drawings, which illustrate the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view diagram of one embodiment of a cylindrical deadbolt assembly with a deadbolt indicator escutcheon apparatus. 
         FIG. 2  is an exploded front view diagram of the deadbolt indicator escutcheon apparatus of  FIG. 1 . 
         FIG. 3  is an exploded rear view diagram of the deadbolt indicator escutcheon apparatus of  FIG. 1 . 
         FIG. 4  is a rear perspective view of the deadbolt indicator escutcheon apparatus of  FIG. 3  in an assembled state, illustrating an indicator and cam mounted to the escutcheon, wherein the cam is configured to be turned by a cylinder tail piece to move the indicator between first and second positions. 
         FIG. 5  illustrates the deadbolt indicator escutcheon apparatus seated within the cylindrical bore of a door, displaying the word “LOCKED” to indicate that the door is locked. 
         FIG. 6  illustrates the deadbolt indicator escutcheon apparatus seated within the cylindrical bore of a door, displaying the word “OPEN” to indicate that the door is unlocked. 
         FIG. 7  is an exploded view diagram of another embodiment of a cylindrical deadbolt assembly with a deadbolt indicator, suitable for use in indicating whether a restroom is occupied. 
         FIG. 8  is an exploded view diagram of a third embodiment of a cylindrical deadbolt assembly with a deadbolt indicator. 
     
    
    
     DETAILED DESCRIPTION 
     Before the subject invention is described further, it is to be understood that the invention is not limited to the particular embodiments of the invention described below or depicted in the drawings. Many modifications may be made to adapt or modify a depicted embodiment without departing from the objective, spirit and scope of the present invention. Therefore, it should be understood that, unless otherwise specified, this invention is not to be limited to the specific details shown and described herein, and all such modifications are intended to be within the scope of the claims made herein. 
     It is also to be understood that terms of art and words in general carry a range of meanings. Language is an imprecise medium of communication. The terminology and grammar employed in this specification is for the purpose of describing and explicating particular embodiments. Unless the context clearly demonstrates otherwise, the particular terms and grammatical structure employed should be liberally construed. 
       FIGS. 1-8  illustrate three embodiments of an apparatus  20  for indicating the setting of a cylindrical deadbolt assembly  10  having at least one keyed cylinder assembly  12  operable to turn a cylinder tail piece  15  to operate a bolt assembly  19 . In  FIGS. 1-6 , the apparatus  20  comprises an escutcheon  30  configured to mount on the inside face of a door  21  and an indicator  50  mounted on an inside surface  35  of the escutcheon  30 . The escutcheon  30  comprises one or more windows  31  for displaying information from the indicator  50 . The indicator  50  is operative to travel between first and second positions to provide a first indication  57  when the deadbolt is locked and a second indication  58  when the deadbolt is unlocked. The apparatus  20  also comprises a mechanical coupling  40 , such as a cam, configured to be turned by the cylinder tail piece  15  to move the indicator  50  between its first and second positions. 
     The indicator  50  comprises a ring  51  with first and second indications  57  and  58  that are angularly spaced from one another. The ring  51  has a central opening  53 , and at least one slot  52  is provided along the perimeter of a central opening  53 . The ring  51  is mechanically coupled to the cylinder tail piece  15  through at least one slot  52 . In one embodiment, dual slots  52  are provided along this perimeter, and the ring is mechanically coupled  40  to the cylinder tail piece  15  through a selected one of the dual slots  52  depending on whether the door is a right-handed or left-handed door. 
     The cam  40  comprises a mechanical coupling configured to move (rotate) the indicator  50  between its first and second positions. The mechanical coupling comprises a hub  43  and a link  44  (such as a pin) rigidly coupled to the hub  43  via a radially distal portion  42  (such as an arm) of the hub  43 . The hub  43  is configured with an aperture  41  through which the cylinder tail piece  15  is inserted to mount the cam  40  on the cylinder tail piece  15 . The link  44  is configured to fit within a slot  52  of the ring  51 . 
     The escutcheon  30  is configured to facilitate movement of the indicator  50  between its first and second indications  57  and  58 . In particular, the escutcheon  30  comprises an outer lip  38  that contacts the inside face of the door  21 , a cylindrical shaped central portion  37  configured to extend into the cylindrical bore  23  of the door  21 , and a seat  36  between the cylindrically shaped central portion  37  and the outer lip  38 . The seat  36 , spaced apart by the outer lip  38  from the door  21 , provides a space for angular travel of the indicator  50  between its first and second positions. 
     To prevent the escutcheon  30  from rotating, first and second apertures  32  are provided to receive mounting screws  11  of the deadbolt assembly  12 . A third aperture  34  is provided for passage therethrough of the cylinder tail piece  15 . 
     In  FIG. 7 , the apparatus  20  comprises an inside collar  12  configured to mount on the inside face of a door  21  and an indicator  50  mounted on an inside surface of the inside collar  12 . The indicator  50  comprises a rotary member having first second indications  57  and  58  that are angularly spaced from one another. The inside collar  12  comprises one or more windows  14  for displaying information from the indicator  50 . The inside collar  12  comprises an outer lip  16  configured to contact the inside face of the door  21 , a cylindrical shaped central portion  13  configured to extend into the cylindrical bore of the door  23 , and a seat  17  between the cylindrically shaped central portion  13  and the outer lip  16 , the seat  17  facilitating angular movement of the indicator  50  between its first and second positions. In most other details, the apparatus of  FIG. 7  is the same as the apparatus of  FIG. 1 . 
     In  FIG. 8 , the apparatus comprises a single cylinder deadbolt assembly with a thumbturn  25  for a non-exit door. It is apparent from the drawing that in most details,  FIG. 8  is the same as the apparatus of  FIG. 1 , but with the indicator  50  labeled with “OPEN” and “IN USE” or similar indications for use on the outside face of a door  22 . 
     The invention encompasses not only indicators made for pre-existing cylindrical deadbolt assemblies, but also cylindrical deadbolt assemblies that include indicators. Accordingly, in one embodiment, a cylindrical deadbolt assembly is provided that comprises a bolt assembly, at least one keyed cylinder assembly operable to turn a cylinder tail piece to operate the bolt assembly, a trim piece configured to mount on the inside face of a door, and an indicator mounted on an inside surface of the trim piece. The indicator is operative to travel between first and second positions to provide a first indication when the deadbolt is locked and a second indication when the deadbolt is unlocked. 
     Although the foregoing specific details describe various embodiments of the invention, persons reasonably skilled in the art will recognize that various changes may be made in the details of the apparatus of this invention without departing from the spirit and scope of the invention as defined in the appended claims.