KEY STORAGE DEVICE

Abstract

A key storage device (1) has a tubular housing (8) having an open proximal end (14) and a distal end (15), and a sliding carriage (2) which is insertable into the proximal end (14) of the housing (8). The sliding carriage (2) has a compartment (4) for a key to be stored, and is displaceable between an open position in which a majority of the sliding carriage (2) is outside of the housing (8) and the compartment (4) is accessible for key retrieval, and a closed position in which the majority of the sliding carriage (2) is inside the housing (8) and the compartment (4) is inaccessible. A lock mechanism (12) is arranged within the tubular housing (8). It has a locked state in which the sliding carriage (2) is kept locked in its closed position and prevented from being displaced to its open position, and an unlocked state in which the sliding carriage (2) may be displaced to its open position. The lock mechanism (12) has a piston (5) and a catch member (7) which are both movable between respective first positions in the locked state of the lock mechanism (12) and respective second positions in the unlocked state of the lock mechanism (12). An electric motor (28) is coupled for causing movement of the piston (5) of the lock mechanism (12). A control unit (35) is adapted to cause the lock mechanism (12) to switch from its unlocked state to its locked state by actuating the motor (28) and thereby causing movement of the piston (5) from its second position to its first position, the movement of the piston (5) in turn causing movement of the catch member (7) from its second position to its first position. The control unit (35) is also adapted, based on an external input (29), to allow the lock mechanism (12) to switch from its locked state to its unlocked state by actuating the motor (28) and thereby causing movement of the piston (5) from its first position to its second position, the movement of the piston (5) in turn allowing movement of the catch member (7) from its first position to its second position.

Claims

1. A key storage device comprising: a tubular housing having an open proximal end and a distal end, a sliding carriage insertable into the proximal end of the housing, the sliding carriage comprising a compartment for a key to be stored, the sliding carriage being displaceable between an open position in which a majority of the sliding carriage is outside of the housing and the compartment s accessible for key retrieval, and a closed position in which the majority of the sliding carriage is inside the housing and the compartment is inaccessible, a control unit, and a lock mechanism arranged within the tubular housing, the lock mechanism having a locked state in which the sliding carriage is kept locked in its closed position and prevented from being displaced to its open position, and the lock mechanism having an unlocked state in which the sliding carriage may be displaced to its open position, said lock mechanism comprising a piston and a catch member which are both movable between respective first positions in the locked state of the lock mechanism and respective second positions in the unlocked state of the lock mechanism, an electric motor coupled for causing movement of the piston of the lock mechanism, wherein the control unit is adapted to cause the lock mechanism switch from its unlocked state to its locked state by actuating the motor and thereby causing movement of the piston from its second position to its first position, the movement of the piston in turn causing movement of the catch member from its second position to its first position; and wherein the control unit is adapted, based on an external input, to allow the lock mechanism to switch from its locked state to its unlocked state by actuating the motor and thereby causing movement of the piston from its first position to its second position, the movement of the piston in turn allowing movement of the catch member from its first position to its second position.

2. The key storage device according to claim 1, the piston being movable in an axial direction of the sliding carriage and comprising a slanted edge, wherein, when the piston is moved towards the first position thereof, it pushes the catch member towards the first position thereof into engagement with the sliding carriage, thereby keeping the sliding carriage locked in its closed position.

3. The key storage device according to claim 1, wherein when the sliding carriage is moved from its closed position to its open position, it pushes the catch member towards the second position thereof.

4. The key storage device according to claim 1, wherein the catch member is a ball or cylinder.

5. The key storage device according to claim 1, wherein the electric motor comprises a drive shaft being operatively connected to a screw which is engaged with a nut which is in contact with the piston, wherein the drive shaft rotates upon actuation of the motor and causes rotation of the screw which drives the nut to push the piston between its first and second positions.

6. The key storage device according to claim 1, wherein the catch member is movable in a direction transversal to the axial direction of the sliding carriage.

7. The key storage device according to claim 1, wherein a distal end of the sliding carriage comprises a forked extension with at least two prongs, wherein at least a first of said at least two prongs comprises a hooked portion for engagement with the catch member of the locking mechanism.

8. The key storage device according to claim 7, wherein at least a second of said at least two prongs acts as a counterstay for the engagement of the hooked portion.

9. The key storage device according to claim 1, further comprising a second housing outside of the tubular at the distal end thereof, the second housing containing the control unit.

10. The key storage device according to claim 9, wherein the second housing further contains one or more batteries for supplying power to the control unit and the electric motor.

11. The key storage device according to claim 9, wherein the second housing comprises a button for enabling the control unit to cause actuation of the motor.

12. The key storage device according to claim 9, wherein the second housing comprises at least one LED which provides visual feedback of the status of the key storage device.

13. The key storage device according to claim 9, wherein the second housing further contains a wireless communication unit for receiving external input to the control unit.

14. The key storage device according to claim 1, wherein the electric motor is a step motor.

15. The key storage device according to claim 1, wherein the electric motor is a DC motor.

16. The key storage device according to claim 1, wherein the tubular housing is made of sturdy metal and is designed to protect the key safely in the compartment while withstanding attempts to steal the key by using external force.

17. The key storage device according to claim 1, wherein the distal end of the tubular housing further comprises a lock unit which comprises the lock mechanism, the electric motor and a first sensor that measures the position of the piston.

18. The key storage device according to claim 17, wherein the lock unit further comprises a second sensor that measures the position of the sliding carriage.

19. The key storage device according to claim 18, wherein the control unit is adapted to prevent movement of the lock mechanism by not actuating the electric motor unless the second sensor indicates that the sliding carriage is in its closed position.

20. The key storage device according to claim 1, wherein a proximal end of the sliding carriage comprises a rotational handle which rotates a locking tongue into, and out of, engagement with a slit in the tubular housing.

21. The key storage device according to claim 1, wherein the electric motor is controlled by the control unit using coded communication.

22. The key storage device according to claim 21, wherein the coded communication involves transmission of encrypted data over a serial communication interface.

23. The key storage device according to claim 1, wherein the lock mechanism is in the unlocked state if the piston is within 5-15% of a maximum distance from the electric motor and is in the locked state if the piston is within 85-95% of the maximum distance from the motor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] By way of example, embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

[0059] FIG. 1 shows an isometric view of a key storage device according to the present invention.

[0060] FIG. 2 shows an exploded isometric view of the same key storage device.

[0061] FIG. 3a shows a front view of the key storage device with an exposed sectional view of the lock mechanism.

[0062] FIG. 3b shows the lock mechanism in a locked state.

[0063] FIG. 3c shows the lock mechanism in an unlocked state.

[0064] FIG. 4a shows a side view of the key storage device.

[0065] FIG. 4b shows a rear view of the key storage device.

[0066] FIG. 5a shows a front view of the key storage device with the sliding carriage in an open position with the compartment accessible.

[0067] FIG. 5b shows the lock mechanism in an unlocked position and the sliding carriage in an open position.

[0068] FIG. 6 shows an arrangement of some main components of the key storage device.

[0069] FIG. 7 shows an exemplifying environment in which the present invention may be exercised.

DETAILED DESCRIPTION

[0070] Embodiments of the invention will now be described with reference to the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the particular embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements.

[0071] FIGS. 1 and 2 show a key storage device 1 according to one embodiment of the invention. It comprises a tubular housing 8 made of steel which protects a key stored inside of a compartment 4 of a sliding carriage 2. A knob 22 is placed at a proximal end 16 of the sliding carriage 2, which rotates a locking tongue 23 into a slit 24 in the sliding carriage 2 which ensures that the sliding carriage 2 is positioned correctly in the tubular housing 8. A second housing 9 is at a distal end 15 of the tubular housing 8, which contains a control unit 35 (FIG. 6) which controls an electric step motor 28 (FIG. 6). Examples of a control unit 35 include a processing unit in the form of, for instance, one or more CPUs and/or DSPs, being programmed to perform its functionality by executing program instructions of a computer program. Alternatively, the control unit 35 may be implemented as an FPGA, ASIC, etc. The second housing also contains a memory 41 (FIG. 6) for the control unit 35, where the memory may be implemented using any commonly known technology for computer-readable memories such as ROM, RAM, SRAM, DRAM, CMOS, FLASH, DDR, EEPROM memory, flash memory, hard drive, optical storage or any combinations thereof. The second housing also contains a wireless communications unit 36 (FIG. 6) for transmitting and receiving for example authorizations to unlock the key storage device 1 or notifications about the activity of the device 1.

[0072] The second housing 9 further comprise a button 30 which activates the power source for the control unit 35 (FIG. 6), in this case a battery 31 (FIG. 6). The button 30 is transparent and fitted with light emitting diodes (LEDs) 19 (FIG. 6) that gives a user feedback. Examples of feedback include: if the power source is active, if a user authorization is successful, if the lock mechanism is in a locked or unlocked state, and if something has gone wrong.

[0073] FIG. 2 shows an exploded view of the key storage device 1. The locking tongue 23 and the slit 24 mentioned above are shown. The compartment 4 for the key to be stored is shown, it is large enough to hold one or more keys. At the distal end 17 of the sliding carriage 2, a forked extension comprises two prongs 18a, 18b, wherein a first of the prongs 18a comprise a hooked portion 3 for engagement with a catch member 7 (FIGS. 3a-c). A second of the prongs 18b acts as a counterstay for the engagement of the hooked portion. For this engagement and counterstay to be effective, the two prongs 18a, 18b are preferably made from a sturdy and resilient material. All of the sliding carriage 2 except perhaps the proximal end 16 beyond the compartment 4 is preferably made from a sturdy material to prevent unauthorized access to the compartment 4.

[0074] A lock unit 20 is arranged at the distal end 15 of the tubular housing 8 and attached by screws 10. The lock unit 20 could be arranged at any position in the tubular housing 8, however by arranging it far away from the open proximal end 14 of the tubular housing 8, security is increased. The lock unit 20 may be attached by many different fastening means equivalent to screws 10 known to the skilled person, such as nails, adhesives and plugs. The lock unit 20 comprises the electric motor 28 and a lock mechanism 12 which comprises a piston 5 and a catch member 7 in the form of a ball.

[0075] The lock unit 20 may also comprise a circuit board 25, which may comprise the electric motor 28; a first sensor 33 for measuring the position of the piston 5 to determine if the key storage device 1 is locked; and a second sensor 34 for measuring the position of the sliding carriage 2 to determine whether the sliding carriage 2 is in an open or closed position.

[0076] A mounting support 21 made from aluminum or steel is fastened using screws to the tubular housing 8. The mounting support 21 is used to securely fasten the key storage device 1 to a secure surface, such as a wall or door. The mounting support 21 may also be shaped to extend around the hinge side of a door and be fastened on the inside of the door. This has an advantage that the fastening means are protected on the inside of the door when the door is closed. Other mounting examples include mounting the tubular housing within a wall with the sliding carriage 2 and the second housing 9 extending beyond the wall, so that they remain accessible.

[0077] FIG. 3a-c show the lock mechanism 12 in a locked (FIG. 3b) and an unlocked (FIG. 3c) state, respectively. In this embodiment, the circuit board 25 comprises an optical sensor 33 for measuring the position of the piston 5 and a limit switch 34 for measuring the position of the sliding carriage 2. When the electric motor 28 is activated, it rotates a drive shaft 32. A screw 11 is arranged on the drive shaft 32 which is rotated along with the drive shaft 32, which is turn rotates a nut 13 which is arranged on the screw 11. As the nut 13 rotates, it moves up or down depending on the direction of rotation, thus pushing on the piston 5 and moving it between its first (FIG. 3b) and second (FIG. 3c) positions. The piston 5 is not at its maximum distance from the electric motor 28 in the first position shown (FIG. 3b), however this is still a locked first position as the ball 7 is prevented from moving further into the lock unit 20. The ball 7 is pushed between its first (FIG. 3b) and second (FIG. 3c) positions by the piston 5, primarily using its slanted edge 6. The ball 7 is made from stainless steel and preferably moves with little friction between its first and second positions.

[0078] In the first position of the ball 7 (FIG. 3b) it engages with the hooked portion 3 of the sliding carriage 2, preventing the sliding carriage 2 from being displaceable within the tubular housing 8. The ball 7 abuts the side of the piston 5 to ensure that a portion of the ball 7 protrudes far enough from the lock unit 20 to sufficiently engage the hooked portion 3 of the sliding carriage 2. The dimensions of the ball 7, the lock unit 20 and the hooked portion 3 need to be carefully managed to achieve a sufficient engagement between the ball 7 and the hooked portion 3 while still allowing unobstructed movement of the piston 7 and the sliding carriage 2. The dimensions and speed of the electric motor 28, the drive shaft 32, the screw 11, the nut 13 and the lock mechanism 12 all need to be balanced to achieve a fast locking and unlocking speed.

[0079] In the second position of the ball 7 (FIG. 3c) it no longer abuts the side of the piston 5 and may move further into the lock unit 20 until it is stopped by the slanted edge 6. In this position, the ball 7 no longer prevents the sliding carriage 2 from being displaced and the key storage device 1 is unlocked. If the ball 7 does not move further into the lock unit 20 automatically, it may be pushed by the hooked portion 3 of the sliding carriage.

[0080] FIG. 4a-b show the key storage device 1 in different perspective views. The tubular housing 8 is made of the same sturdy metal at all of its sides to prevent any one side from being a security risk. The front side of the tubular housing 8 may also comprise a support structure to further reinforce the metal. The mounting support 21 also needs to be made from a sturdy metal and securely fastened both to the tubular housing 8 and the secure surface it is fastened to, to prevent someone from stealing the entire key storage device and breaking it open later with heavy machinery. The key storage device 1 is preferably safe to use outdoors, meaning that the housings 8, 9 need to be water proof and the electronics and moving parts need to withstand high and low temperatures.

[0081] FIG. 5a-b show the key storage device when the sliding carriage 2 is in an open position with the compartment 4 accessible. FIG. 5a shows the compartment 4 accessible for key storage and retrieval. FIG. 5b shows the lock mechanism 12 when the sliding carriage 2 has been displaced. To prevent the ball 7 from moving out of the lock unit 20, specific dimensions of the lock unit 20, the tubular housing 8 and the ball 7 may be used.

[0082] FIG. 6 shows a schematic view of the various groupings of possible components according to the present invention. The lock unit 20 may preferably be arranged within the tubular housing 8, for security reasons. The second housing 9 may preferably be arranged outside of the tubular housing 8. An advantage of this is that it allows for components that are not sensitive to unauthorized access for security reasons to be arranged in a housing that simplifies replacement of broken or worn out components, such as the battery 31. This also allows the wireless communication unit 36 to not be shielded by the sturdy metal of the tubular housing 8, which increases performance.

[0083] However, the control unit 35 still needs to be able to communicate control signals 26 with the electric motor 28, which needs to be in the tubular housing 8 for security reasons. There is therefore a communication interface 27, 27′ between the control unit 35 and the electric motor 28. Examples of possible communication interfaces 27, 27′ are wireless transmitters/receivers and wires. The communication 26 will also need to be coded, to prevent unauthorized control of the electric motor 28. Examples of coding are encryption. In case the electric motor 28 is a step motor and the communication interface 27, 27′ is a serial wire connection, the step motor 28 may be adapted to only accept communication 26 with a specific pulse frequency and pulse length and only on specific wires.

[0084] Once the electric motor 28 has received and accepted the communicated control signals 26 from the control unit 35, it may rotate the drive shaft 32 which rotates the screw 11, which rotates the nut 13, which pushes the piston 5, which ultimately pushes the ball 7 between the first and second positions. The communication interface 27, 27′ may also optionally be adapted to receive information from the sensors 33, 34 for measuring the position of the piston 5 and the sliding carriage 2, respectively, and transmit 26 this information to the control unit 35. The control unit 35 may then use this information to give slight adjustments to the electric motor 28 or prevent it from moving.

[0085] FIG. 7 shows an exemplifying environment in which the present invention may be exercised. Many different use cases are possible in the shown environment and many other with different environments are also possible. One example is that the wireless communication unit 36 of the key storage device 1 may be adapted to receive 29 authorization information from a portable communication device 39, such as a mobile phone or key fob, which is transmitted to the control unit 35, which unlocks the key storage device 1. A user may need to press the button 30 before the wireless communication unit 36 will be able to accept authorization information. The authorization information may be stored locally on the portable communication device 39 and may be selectable from a list of several different authorization information sets for different key storage devices 1. The portable communication device 39 may also receive the authorization information from a server 37, which retrieves the information from a secure database 38. The portable communication device 39 may need to present authorization such as a user name and password to access the authorization information for the key storage device. The communication unit 36 of the key storage device 1 may also transmit 29 information to the portable communication device 39, such as notifications that a locking or unlocking procedure has succeeded or failed. The communication unit 36 of the key storage device 1 may also transmit 29 information to the server 37, such as status updates and security alerts. The server 37 may relay this information to several different portable communication devices 39 and it may store the information in the secure database 38. The authorization information may be an encryption key that is generated at the first installation of the key storage device 1 and stored in the secure database 38 via communication with the server 37 and optionally the portable communication device 39.

[0086] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. In cases where advantages, benefits or solutions to problems are described herein, it should be appreciated that such advantages, benefits and/or solutions may be applicable to some example embodiments, but not necessarily all example embodiments. Thus, any advantages, benefits or solutions described herein should not be thought of as being critical, required or essential to all embodiments or to that which is claimed herein. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.