Patent Publication Number: US-6666053-B2

Title: Reversible spring-loaded lock slide

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to lock slides, and relates more particularly to a reversible spring-loaded lock slide. 
     BACKGROUND 
     Doorknobs and latch handles are well known in the prior art for providing a mechanism by which a user can open or close a door or cabinet. Often, such handle assemblies are provided with a handle that can be rotated by the user. A lock cam may be provided, being attached to a shaft connected to the handle. This lock cam has a latching arm extending therefrom that rotates into or out of an opening in a door jamb. In addition to doors, handle assemblies can also be used in opening cabinets, drawers, or for other similar applications. 
     Handle assemblies need to be connected to the cabinet or door. Also, the latching arm on the lock cam needs to be positioned so that it will enter an opening in the door jamb or wall. When engaged in this opening, pulling on the handle will not open the cabinet or door because the latching arm will catch on the door jamb and prevent motion. When the latching arm is swung out from this opening, nothing impedes its motion and the door can be freely swung or slid into the open position. 
     Mechanisms used to lock the lock cam of a handle assembly in a position and hence prevent the door or cabinet from being opened are known in the prior art. Typically, a lock slide is moved into an opening in the lock cam. The lock cam is prevented from rotating due to the presence of the lock slide. The lock slide itself is prevented from moving due to its connection with a lock cylinder having a key a user may turn. Turning of the key results in linear movement of the lock slide out of the opening in the lock cam, and hence allows the door to be opened. 
     T-handle and D-ring handle door latches are typically employed on emergency vehicles, such as fire engines and ambulances, due to their relatively simple but reliable mechanisms, and their attractive appearance and aerodynamic shape. These handle assemblies have the handle positioned inside of a recess in the surface of the vehicle. A user will generally rotate the handle in one plane so that it is no longer positioned inside of the recess. Next, the user will rotate the handle in a perpendicular plane that will result in the door being opened. A door latch which is representative of the prior art is a locking, folding, T-handle door latch produced by Hansen International of Columbia, S.C. 
     Although the prior art provides a handle assembly that makes use of a locking cylinder to lock a lock cam in place, the prior art does not provide a way to use the same locking cylinder in a handle assembly when the depth of the tray is made shallower or deeper. The prior art would require a newly sized locking cylinder to be used if the location of the tray or lock slide were changed. Additionally, the prior art requires a newly sized tray and/or lock slide to be used if the length of the lock cylinder is varied. The present invention overcomes these deficiencies by providing a reversible spring-loaded lock slide that can compensate for size changes in the lock cylinder, tray, and/or lock slide. 
     SUMMARY 
     Objectives and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     According to one aspect of the invention, a handle assembly is provided. The handle assembly is composed of a tray that has opposite sides. Also, a shaft is provided that rotatably extends through the tray. A handle is connected to the shaft so as to rotate the shaft relative to the tray, and the handle is on one side of the tray. A lock cam is on an opposite side of the tray. The lock cam is connected to the shaft so as to rotate with the shaft relative to the tray. The lock cam has at least one lock slide opening. 
     A reversible spring-loaded lock slide assembly having a lock slide is present. The lock slide has a body with an end movable into the lock slide opening to lock the lock cam. The lock slide has a contact member extending substantially perpendicular to the lock slide body on one end of the lock slide. The lock slide is mountable within the lock slide assembly in two orientations. A spring is provided in order to bias the lock slide in an unlocking direction. A lock arm is engageable with the contact member of the lock slide. Engagement of the lock arm with the contact member urges the lock slide in a locking direction. 
     Another aspect of the invention may include a handle assembly as discussed above further having a lock cylinder that engages the lock arm. Rotation of the lock cylinder causes the lock arm to rotate. 
     A further configuration of the invention may include a handle assembly as discussed above wherein the contact member of the lock slide has a planar surface. 
     Also, the invention may include a handle assembly as discussed above further including a spring-loaded slide case attached to one side of the tray. The lock slide is in sliding engagement with the spring-loaded slide case. One end of the spring contacts the spring-loaded slide case. 
     In another aspect of the present invention, a reversible spring-loaded lock slide assembly for use in locking a door latch is provided. This lock slide assembly includes a spring-loaded slide case. Also, a lock slide is placed in sliding engagement with the spring-loaded slide case. The lock slide has a contact member located at one end, and is capable of being placed in two orientations. The lock slide also has a first cavity and a second cavity. A spring is provided to bias the lock slide relative to the spring-loaded slide case. 
     Also according to another aspect of the present invention, a handle assembly for use in opening a compartment is provided. The handle assembly includes a tray having opposite sides with a shaft rotatably extending through the tray. A handle is connected to this shaft in order to provide the rotational movement. The handle is located on one side of the tray. A lock cam is connected to the shaft so as to rotate with the shaft relative to the tray. The lock cam being on an opposite side of the tray. The lock has at least one lock slide opening. A spring-loaded slide case is connected to the tray. Also, a reversible spring-loaded lock slide assembly is provided. The lock slide is moveable into the lock slide opening in order to lock the lock cam. The lock slide assembly has a lock slide that has a body with an end movable into the lock slide opening in order to lock the lock cam. The lock slide has at least two cavities and has a contact member at one end. The lock slide is in sliding engagement with the spring-loaded slide case, and is capable of engaging the spring-loaded slide case in two orientations. Also provided is a spring that is used to bias the lock slide relative to the spring-loaded slide case. Additionally, a lock arm that has a cam surface is provided. The cam surface is engageable with the contact member of the lock slide. Engagement of the lock arm with the lock slide causes the lock slide to be urged in a direction opposite to the bias of the spring. 
     Another aspect of the present invention includes the handle assembly as described above further including a lock cylinder that engages the lock arm. Rotation of the lock cylinder causes the lock arm to rotate. 
     Also, the invention includes an embodiment of the handle assembly as described above wherein the contact member of the lock slide has a planar surface. 
     Yet another aspect of the present invention includes an embodiment of the handle assembly described above wherein the spring is contained within one of the cavities and engages the spring loaded slide case at one end of the spring. The spring biases the lock slide away from the lock slide openings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a back view of a D-ring handle assembly using an embodiment of a lock slide assembly according to certain aspects of the present invention. The drawing shows the lock cam of the lock slide assembly in a locked position. 
     FIG. 2 is a partial sectional side view of the handle assembly taken along line  2 — 2  in FIG. 1 with only the tray portion in section for clarity. 
     FIG. 3 is a close-up view of the lock slide assembly shown in FIG.  1 . The drawing shows the lock slide and the lock arm in both a locked (dotted lines) and an unlocked (solid lines) position. 
     FIG. 4 is an exploded perspective view of an embodiment of a lock slide assembly of the present invention. 
     FIG. 5 is a back view of an alternate D-ring handle assembly having a lock cam having four lock slide openings. 
     FIG. 6 is a partial sectional side view of the handle assembly taken along line  6 — 6  of FIG. 5, with only the tray portion in section for clarity. 
     FIG. 7 is a back view of an alternate folding-T handle assembly using an embodiment of a lock slide assembly according to certain aspects of the present invention. The drawing shows the lock cam in a locked position. 
     FIG. 8 is a partial sectional side view taken along line  8 — 8  of FIG. 7, with only the tray portion in section for clarity. 
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include such modifications and variations. 
     Referring now to the drawings, FIG. 1 shows one example of a handle assembly indicated generally at  10  for use in opening a door or cabinet in accordance with certain aspects of the present invention. The handle assembly  10  includes a tray  12  having optional tray holes  22  disposed about a surface of tray  12 . The tray holes  22  may be used to mount the tray  12  onto a door or other compartment. The surface of tray  12  having tray holes  22  is either flush with the surface that the tray  12  is attached to, or lies just on top of the surface. Such a tray  12  is often used in many applications due to its attractive and modular appearance. 
     The handle assembly includes a latching arm  20  that is swung inside of a hole in a door jamb. Once inserted into such a hole, the door onto which the handle assembly  10  is attached cannot be opened. Additionally, latching arm  20  can be configured to prevent the door from opening by contacting a flange in a certain position or by its incorporation with other mechanisms. The latching arm  20  is connected to a lock cam  18 . If lock cam  18  is prevented from moving, it necessarily follows that latching arm  20  is also prevented from moving due to its connection to lock cam  18 . Lock cam  18  is connected to a shaft  14  by a nut  16 . Shaft  14  rotates relative to tray  12 , so lock cam  18  therefore can rotate relative to tray  12 . As shown, lock cam  18  is provided with two lock slide openings  24 . 
     A reversible spring-loaded lock slide  28  is configured to move into one of the lock slide openings  24 . Once the lock slide  28  is inside, lock cam  18  is prevented from moving due to the contact with an end  33  of the lock slide  28 . The lock cam  18  is provided with two stops  29  in order to allow for only 90 degrees of rotation of the lock cam  18 . Of course, lock cam  18  can be configured without these two stops  29  in order to allow the lock cam  18  to rotate 360 degrees, and with any number or spacing of openings  24 . 
     Handle assembly  10  also includes a compression spring  36  that biases lock slide  28  in an unlocking direction. Both spring  36  and lock slide  28  are at least partially contained within spring-loaded slide case  38 . Lock slide  28  is moveable relative to the spring-loaded slide case  38 . Spring-loaded slide case  38  is attached to tray  12  via two rivets  26 . The spring  36  is configured within lock slide  28  and contacts spring-loaded slide case  38  at a flange  54  extending from slide case  38 . Spring  36  biases lock slide  28  into a position away from the lock cam  18 . In such a fully biased position, lock slide  28  is completely removed from the lock slide openings  24  and hence lock cam  18  is free to rotate relative to tray  12 , at least within the limits of stops  29 . When spring  36  is compressed, lock slide  28  may move into one of the lock slide openings  24 . Such a situation results in lockage of lock cam  18 . 
     The mechanism used to compress spring  36  is shown in FIG. 1 as lock arm  30 . Lock arm  30  is connected to and rotates with lock cylinder  32 . Lock cylinder  32  is connected to tray  12  by nut  34 . Actuation of the lock cylinder  32  causes lock arm  30  to rotate. Rotation towards a planar surface on lock slide  28  eventually results in contact between the two. Further rotation results in a compression of spring  36  and movement of lock slide  28  towards the lock cam  18 . If a lock slide opening  24  is aligned with the lock slide  28 , the lock slide  28  will enter the lock slide opening  24  and lock the handle assembly. Rotation of the lock arm  30  away from the planar surface of lock slide  28  causes the lock slide  28  to move linearly away from lock cam  18 . This eventually results in the lock slide  28  being removed from the lock slide opening  24  and hence allows the lock cam  18  and latching arm  20  to rotate. 
     FIG. 2 shows a partial sectional side view taken along line  2 — 2  of FIG.  1 . Latching arm  20  is shown as having a curved section, although it is to be understood that the latching arm  20  may be of various configurations. Lock cam  18  is attached to the shaft  14  by a nut  16  and washer  46  combination. The handle  40  shown in FIG. 2 is a D-shaped handle having a section being angled away from the tray  12 . A handle connection arrangement  42  is shown being used to attach handle  40  to the shaft  14 . Handle  40  can be rotated away from tray  12  out of the compartment in tray  12  and then rotated about the shaft. A handle biasing assembly  44  is provided to allow for a smooth outward movement and rotation of handle  40 . A handle biasing assembly  44  is also used to properly space the lock cam  18  from tray  12 . 
     FIG. 3 shows an enlarged view of the lock slide assembly of FIG.  1 . FIG. 3 shows the lock cam  18  in both a locked and an unlocked arrangement. Shown in solid lines, when the lock arm  30  is rotated away from the lock cam  18  the lock slide  28  also moves away from lock cam  18  due to the spring  36  biasing force until the lock slide  28  contacts flange  54 . In such an arrangement, lock cam  18  is free to rotate relative to tray  12 . Shown in phantom lines, when the lock arm  30  is rotated towards the lock cam  18 , the lock slide  28  is forced into lock slide opening  24 . In such a configuration spring  36  is compressed. Lock slide  28  is shown in phantom lines being placed inside of lock slide opening  24  and hence locking the lock cam  18  and preventing it from rotating relative to tray  12 . 
     FIG. 4 shows an exploded perspective view of the reversible spring-loaded lock slide assembly  46  of the present invention. Lock slide  28  is shown as having two cavities  48 . A wall  50  separates these two cavities  48 . A contact member  52  is provided at one end of lock slide  28  and contacts both the wall  50  and also the two cavities  48 . A spring-loaded slide case  38  is provided with two holes  39 . Rivets  26  are inserted into these two holes  39  to connect the spring-loaded slide case  38  to another structure. Spring  36  is housed within one of the cavities  48 . Spring  36  is engaged on one end against contact member  52  and on the other end against flange  54 . 
     Referring back to FIG. 2, it can be seen that lock arm  30  engages the lock slide  28  at the contact member  52 . This engagement occurs at one end of the contact member  52 . If it were the case that lock cylinder  32  were longer it could be the case that lock arm  30  would not engage contact member  52  at all. In order to compensate for various lengths of lock cylinders, and also for various depths and sizes of tray  12 , the present invention allows for a user to reconfigure the reversible spring-loaded lock slide assembly  46  so that the lock arm  30  engages contact member  52  of the lock slide  28 . This adjustment is found by way of inverting the position of the lock slide  28  and positioning the spring  36  within the second cavity  48 . As can be seen from FIG. 4, reversal of the lock slide  28  so that the opposite cavity  48  is used results in the direction of extension of the contact member  52  also being reversed. This reversal of contact member  52  allows for a change in its position relative to the lock arm  30 . Such a position change would be necessary in order to ensure engagement of the lock arm  30  and contact member  52  if various sizes of lock cylinders  32  and  104  trays  12  are used. Additionally, this reversal allows for other dimensional variations to be compensated for. 
     FIG. 5 shows an alternative embodiment of the handle assembly for use in opening a compartment of the present invention. The drawing shows a back view of such an assembly. The handle assembly of FIG. 5 differs from the handle assembly of FIG. 1 in that the lock cam  18  and shaft  14  are slightly different. Lock cam  18  is here provided with four lock slide openings  24 . Shaft  14  is different in that it provides for a lock key  60  to attach the lock cam  18  to shaft  14 . In FIG. 1, this attachment arrangement consists of a nut  16  being used to attach shaft  14  to lock cam  18 . 
     FIG. 6 is a partial sectional side view of the handle assembly of FIG. 5 taken along line  6 — 6  of FIG.  5 . The handle  40  is shown in this drawing as a D-ring handle. The D-ring handle  40  is connected to the shaft  14  through a connection arrangement  42 . A lock cam spacer  56  is provided to appropriately space the lock cam  18  from tray  12 . A key  58  is shown inserted into lock cylinder  32  in order to actuate lock cylinder  32  and hence rotate lock arm  30 . Engagement of lock arm  30  with lock slide  28  causes the lock slide  28  to move into or out of one of the four lock slide openings  24 . The position of lock slide  28  is the same, relative to the slide case  38 , in FIGS. 2 and 6. 
     FIG. 7 is an alternative embodiment of the handle assembly of the present invention. Latching arm  20  is shown in this drawing as being a single arm extending from lock cam  18 . Unlike the latching arm of FIG. 1, the latching arm in FIG. 7 does not have a curved section. Also, a lock key  60  is used in place of the nut  16  to attach the lock cam  18  onto shaft  14 . The lock slide assembly used in FIG. 7 is similar to that discussed in the previous embodiments, although the position of lock slide  28  is reversed. 
     FIG. 8 shows a partial sectional side view of the handle assembly of FIG. 7 taken along line  8 — 8  of FIG.  7 . The handle  40  used in this embodiment is a folding T-lock handle. Such a handle rotates about the connection  42  to shaft  14 . Connection  42  is shown in this drawing as a pin which allows the folding T-lock handle  40  to rotate out of the tray  12 . Once rotated out, folding T-lock handle  40  can be rotated by a user. A handle biasing assembly  44  is provided to allow for a smooth removal and rotation of the folding T-lock handle  40 . 
     The reversible spring-loaded lock slide assembly  46  is reversed in the embodiment shown in FIG. 8 from that embodiment shown in FIG.  6 . This is due to the fact that lock arm  30  does not extend past the recess in tray  12  in FIG.  8 . Reversal of the lock slide  28  allows the lock arm  30  to engage the contact member  52 . As can be seen, the same reversible spring-loaded lock slide assembly  46  can be used on different assemblies having various locations of the lock arm  30  and lock cam  18  (due to the depth of the recess in tray  12 ). Using the same assembly  46  on different handles allows for a more economical, modularized, and uniform product. 
     It will be appreciated that various modifications and changes may be made to the above described preferred embodiments of a reversible spring-loaded lock slide assembly and a handle assembly without departing from the scope of the following claims.