The present invention relates to an electronic locking device and relates particularly, but not exclusively, to a locking device for use on a door such as an internal door in a building.

The use of an electronic lock to control the locked and unlocked conditions of a door, window or the like via a key card, keypad, RFID key or battery powered key is well known. They typically comprise of a cylinder, a plug and a pin which can either straddle the junction between the cylinder and pin or not to prevent and allow the plug to rotate within the cylinder. The position of the pin is controlled by a small electromechanical device such as a motor or solenoid. However, solenoids can on occasion be overcome by the use of a strong magnetic field. The magnetic field acts on the magnets or solenoid within the cylinder and can effectively move the pin into the unlocked condition without the use of the correct key device.

It is generally the case that where an electronic lock is provided to regulate entry into a room or building that the exit through the same door is not restricted. It is preferable that this can be achieved by a mechanical unlocking of the door and this should be possible by a simple instinctive action such as the turning of the handle. It is important that no complex mechanical interaction is required since the mechanical egress through the door is provided a safety feature when there is a need to urgently evacuate a building, for example, in the event of a fire. This is a requirement of many safety regulations such as BS9999:2017.

Preferred embodiments of the present invention seek to overcome or alleviate the above described disadvantages of the prior art. According to an aspect of the present invention there is provided an electronic locking device comprising:- a cylinder; a plug rotatable within said cylinder, wherein the boundary between said cylinder and said plug defines a shear line; at least one processor for receiving signals from an electronic lock controlling device; a locking pin for movement between a locked condition wherein said locking pin straddles said shear line and an unlocked condition wherein said locking pin does not straddles said shear line; a first pin mover to control the position of said locking pin relative to said shear line, said first pin mover controlled by said processor; at least one biasing member for biasing said locking pin towards said locking condition; a rotary member connected to said plug and having a first part annular recess associated therewith providing a first cam surface; and a second pin mover with a surface to engage said first part annular recess, wherein said second pin mover has a second cam surface that acts on said locking pin to move said locking pin between said locked and unlocked conditions, said second pin mover being biased towards the rotary member; wherein rotation of the rotary member causes said first cam surface to move and said second pin mover to move said locking pin from said locked condition to said unlocked condition without rotation of the plug, then further rotation of said rotary member causes rotation of said plug.

By providing a first pin mover under the control of the processor and a second pin mover controlled by the rotary member during the first portion of the turn of the rotary member after which further rotation of the rotary member causes rotation of the plug within the cylinder, the advantage is provided that a simple mechanical mechanism for controlling the unlocking of the locking device can be provided in addition to the electronically controlled first pin mover. This simple mechanical movement is the rotation of the rotary member this and the two separate actions resulting from that rotation are invisible and substantially imperceptible to a person operating the locking device. As a result, mechanical exit through a door is possible irrespective of the locking status of the door from the electronic lock. Even in the event of a loss of power to the electronic locking side the mechanical exit through the door is still possible, whereas the powerless lock would remain secure from outside.

The device may further comprise a second part annular recess formed in one of said rotary member and said plug and a protrusion extending into said second part annular recess from the other of said rotary member and said plug such that rotation of the rotary member relative to the plug does not cause rotation of the plug until said protrusion abuts an end of said second part annular recess, wherein when said protrusion abuts said end of said second part annular recess further rotation of said rotary member causes rotation of said plug.

In a preferred embodiment the second pin mover comprises:- a first end surface for engaging said first cam surface; a second end surface for engaging said biasing member; a first body portion adjacent said first end surface and having a first cross-sectional dimension; a second body portion adjacent said second end surface and having a second cross-sectional dimension less than said first cross- sectional dimension; and, a second cam surface wherein said second cam surface comprises a transition portion between said first body portion and said second body portion.

In another preferred embodiment the transition portion is frustoconical.

By providing the second pin mover in the shape described above, the advantage is provided that the second pin mover can operate by extending through an aperture formed in the locking pin. Because the second body portion has a cross-sectional dimension less than the first body portion and a cam surface extends between the two, the second body portion does not interfere with the movement of the locking pin under the electronic control of the first pin mover when the door is being unlocked using the electronic locking mechanism.

In a further preferred embodiment the locking pin has an aperture or recess whereby said second body portion extends at least partially therethrough.

Preferably engagement of the protrusion with said end of second part annular recess occurs at substantially 30 degrees.

In a preferred embodiment the cylinder member comprises of a Eurocylinder lock.

In a further preferred embodiment the control processor can receive a signal from a key and selectively activate said first pin mover in response to a correct signal.

The first pin mover preferably comprises a motor and an eccentrically mounted cam which engages said locking pin whereby activation of said motor causes rotation of said cam to move said locking pin.

In a preferred embodiment the biasing member comprises a spring. The locking device may also further comprise at least one latch which rotates in response to rotation of said plug.

Preferred embodiments of the present invention will now be described, by way of example only, and not in any limitative sense with reference to the accompanying drawings in which:-

Figure 1 and 2 are perspective views of a locking device of the present invention;

Figure 3 is an exploded perspective view of the locking device of figure 1;

Figure 4 is a sectional view of the locking device of figure 1 shown in a locked condition;

Figure 5 is a similar sectional view to figure 1 with some components of the locking device shown in an unlocked condition;

Figure 6a is a closeup internal view of a portion of the locking device of figure 1;

Figure 6b is a sectional view through two of the components shown in figure 6a;

Figure 7 is five views of a component of the locking device of figure 1 including perspective view in 7a and 7b, a view from one end in 7c and the other in 7d as well as a sectional view in 7e;

Figures 8a and 8b are perspective and side views of another component of the locking device of figure 1;

Figure 9 is a sectional view of the locking device of figure 1 this sectional view cuts through a handle and being perpendicular to the views of figures 3 and 4; and

Figure 10 is a perspective view of a further component of the locking device of figure 1.

Referring to all of the figures, an electronic locking device 10 includes a cylinder 12 and a plug 14 located in use within the cylinder. As can be seen from the figures, the cylinder and plug are of the type known to persons skilled in the art as a Eurocylinder, although it should be noted that the present invention is not limited to the use of cylinders and plugs of this type.

Rotation of the plug 14 in the cylinder 12 is allowed or prevented dependent upon the position of a locking pin 16. The boundary between the cylinder 12 and the plug 14 defines a sheer line indicated at 18 on the figures (see particularly figures 4 and 5). The so-called sheer line can be regarded either as the junction of the cylindrical internal surface of the cylinder 12 and the external cylindrical surface of the plug 14 or as a line on one of these boundaries which extends through the locking pin 16 running parallel to an axis of the plug and cylinder.

In an unlocked condition, the locking pin 16 is contained entirely within a recess 20 in the cylinder 12 and therefore does not straddle the share line 18. In contrast, in a locked condition, the locking pin 16 straddles the share line 18 extending partially into a further recess 22 in plug 14 whilst remaining partially in the recess 20. When in the locked condition the plug 14 is unable to rotate relative to the cylinder 12 whereas in an unlocked condition the plug 14 is free to rotate within the cylinder 12. Rotation of the plug 14 causes rotation of a latch 24 which is attached to the plug 14 and this latch in turn acts on a mechanism of a door, window, or the like which the locking device 10 is designed to control (this further mechanism is not shown, does not form part of the present invention and if familiar to person skilled in the art).

The locking pin 16 is biased towards the locking condition by a biasing member in the form of a spring 26 which is retained within the recess 20 in cylinder 12 by a capping plug 27 which sits in an end of the recess 20 furthest away from the plug 14. This recess 20 extends through the whole of the cylinder 12 and provides the access into which the locking pin 16 and spring 26 are introduced into the cylinder 12. An aperture or recess 28 is formed in the locking pin 16 perpendicular to the axis of the pin and the recess 20. This recess 28 is most clearly shown in figure 6 and is in the form of a section of the locking pin 16 which has been removed.

The locking device 10 is provided with two mechanisms for moving the locking pin 16 between the locked and unlocked conditions. An important aspect of the present invention is that the locking device 10 is used on a door which controls the opening of the door from one side, typically regarded as the outside, electronically requiring a correct electronic key or entry of a correct code on an electronic keypad, but allows the opening of the door in the other direction, from the inside, mechanically and without the requirement for any form of key. In other words, the door can be opened from the inside by simple turning of a handle.

The electronic locking from the outside utilises a first pin mover in the form of a first cam 30 (shown in detail in figure 7) which is rotated by a rotary motor 32 under the control of a processor 34. The processor 34 receives a signal from any suitable electronic lock interface. In figures 1 and 3 an electronic key interface 33 for receiving an electronic key with a power supply and code generator is shown. However, other examples of such interfaces include, but are not limited to, a keypad, an RFID tag or the like. The cam 30 is mounted to an axle 36 asymmetrically with a D-shaped recess 35 into which the axle (also D-shaped) is received. The centre of rotation of the cam 30 is indicated in figure 7 at 37. As can be seen in figure 7c, the cam 30 is approximately circular in shape with the dimensions showing a diameter of 6.5mm. The axis of rotation 37 of the cam 30 is offset towards the top of the cam (as shown in figure 7c) so that it is 2.5mm from the uppermost edge and 4mm from the lowermost edge. As a result, when the cam 30 rotates the 180° the cam surface displaces by 1.5mm.

The mechanical mechanism for moving the locking pin 16 into the unlocked condition utilises a rotary member in the form of a handle 38. This handle is provided to be grasped by a person wanting to exit through the door and it is rotation of that handle which ultimately moves the locking pin 16 from straddling the sheer line 18 and causes rotation of the plug 14 within cylinder 12. This action is in two parts and requires, firstly, the moving of the locking pin 16 from the locked to the unlocked condition followed by the rotation of the plug 14 within the cylinder 12.

The movement of the locking pin 16 from straddling the sheer line 18 is achieved using a second pin mover 40 which sits in a recess 42 formed in the cylinder 12 (see in particular figures 6 and 8). The recess 42 (containing the second pin mover 40) is perpendicular to the recess 20 (containing the locking pin 16). These recesses, and therefore the locking pin 16 and second pin mover 40, are slightly offset to one side of each other as can been seen particularly in figure 6b which is a sectional view through the locking pin and the second pin mover. This offset is used because the diameter of the locking pin and the pin mover are approximately the same and by offsetting the thickness of the locking pin 16 at the recess 28 leaves sufficient material adjacent the recess. A biasing member, in the form of spring 44, urges the second pin mover in a direction outward of the recess 42, that is towards the handle 38. The second pin mover is a specifically shaped pin having a first end surface 46 and a second end surface 48 which engages the spring 44. Adjacent the first end surface 46 is a first body portion 50 which has a first cross-sectional dimension, in the example shown this dimension is a diameter since the second pin mover is circular in cross-section. A second body portion 52 is located adjacent the second end surface 48 and has a cross- sectional dimension, also diameter, substantially the same as that of the first body portion 50. Between the first and second body portions 50 and 52 is a third body portion 54 which has a cross-sectional dimension significantly smaller than those of the first and second body portions. Between the third body portion and the first body portion is a frustoconical body portion 56 which joins the first body portion to the third body portion and provides a cam surface 58. The third and frustoconical body portions 54 and 56 extend through the aperture 28 in the locking pin 16 and it is the interaction of the cam surface 58 with surfaces of the aperture 28 which cause the mechanical movement of the locking pin 16.

Referring now to figure 10, movement of the second pin mover 40 is achieved by a part annular recess 60 formed in, or associated with, the rotary member that is handle 38. This part annular recess 60 is provided with a tapered surface, meaning that the depth of the recess 60 reduces through the arc of the part annular recess. Preferably, the part annular recess 60 is symmetrical in shape with a deepest portion at its centre and therefore the depth of the recess reduces irrespective of the direction of rotation of the handle. This tapered cam surface 62 of the part annular recess 60 engages first end surface 46 of the second pin mover 40 and as a result, rotation of the handle 38 causes movement of the second pin mover 40 against the biasing force of the spring 44.

The handle 38 is connected to the plug 14 by a portion 64 of the plug which extends beyond the cylinder 12. The end portion of the plug 64 has a part annular or arced recess 66 which has ends 68. The handle 38 includes a handle pin 70, a protruding end 72 of which extends into the part annular recess 66. The handle pin 70 is inserted into the handle through an aperture 74 and is sealed with a handle plug 76 which prevents the handle pin from moving relative to the handle 38. The end portion 64 of plug 14 is not fixed to the handle 38 and as a result, the handle can partially turn without causing rotation of the plug 14.

Operation of the electronic locking device 10 will now be described initially looking at the electronic locking mechanism which is used to control access through a door or the like. It should be noted that in figure 4 the locking device is shown in a locked condition with the locking pin 16 straddling the sheer line 18. The processor 34 receives a signal from the external interface (keypad, electronic lock, RFID tag or the like) on the outside of the door and determines if the signal contains the correct code indicating that the lock should move to an unlocked condition. When the correct code is received a signal and power is sent to the motor 32 which causes the rotation of the cam 30 through 180°. A cam stop 82 protruding from the cam 30 engages a corresponding stop (not shown) formed in the plug 14 which prevents further rotation of the cam. This causes a change in the current drawn by the motor which is detected by the processor which recognises this as a signal to stop the motor. The eccentric positioning of the axle 36 in the cam 30 causes the surface of the cam to press against the locking pin 16 pushing it against the biasing force of the spring 26, into the recess 20. After the full 180° rotation of the cam 30, the locking pin has moved 1.5mm resulting in it no longer crossing the sheer line 18 and putting the locking device 10 into the unlocked condition. As a result, the plug 14 is able to rotate within the cylinder 12 and rotation of the plug from the outside (that is, the side opposite to the side with a handle 38) causes rotation of the latch 24, allowing the door to be opened. Because it is the third body portion 54, that is the thinnest part, of the second pin mover 40 that extends through the aperture 28 in the locking pin 16, the second pin mover does not interfere with the movement of the locking pin by the cam 30. After a predetermined period of time, the processor provides a reverse current to the motor 32 causing it to rotate back through 180° (in the opposite direction as the previous term) which causes the cam 30to return to the original position where the locking pin 16 crosses the sheer line 18 and the locking device 10 is in a locked condition once again. Even if the plug 14 remained rotated after that predetermined period of time, the locking pin 16 would engage an inner surface of the cylinder 12 until the plug was rotated back to the starting position where the recess 22 in the plug is aligned with the recess 20 in the cylinder and the locking pin would then snap back into the recess 22 under the force of the spring 26.

It is important that the mechanical release mechanism is able to operate from the inside without the need for a key, allowing access through the door, typically to exit a room or building, without needing a key. This is achieved by rotation of the rotary member, the handle 38. In the locked condition the second pin mover 40, under the biasing force of the spring 44, is pressed into the deepest part of the part annular recess 60 formed in the handle 38. In this condition, the third body portion 54, that is the thinnest portion of the second pin mover 40, is located in the aperture 28 in locking pin 16. As the handle 38 rotates the tapered cam surface 62 of part annular recess 60 presses against the first end surface 46 of the second pin mover 40 pushing it against the force of the spring 44 and further into the recess 42. Because the locking pin 16 is biased towards the plug 14, the lowermost surface 78 (that is the one furthest away from the plug 14) of the aperture 28 in locking pin 16 is initially in engagement with the third body portion 54 of the second pin 40. As the second pin mover 40 is pushed into the recess 42 the frustoconical body portion 56 of the second pin mover 40 engages an edge of the lower surface 78 of the aperture 28 and, acting as a cam surface, that movement causes the frustoconical surface 80 of the frustoconical body portion 56 to push the locking pin 16 downwards, away from the plug 14. When the handle 38 is rotated around the arc of the part annular recess 60 so that the first end surface 46 engages the end of the tapered cam surface 62, the locking pin 16 has moved so as to no longer straddle the sheer line 18, thereby putting the locking device 10 in an unlocked condition. It should be notes that in exploded view of figure 3, the second pin mover is shown in both positions described above, that is in the deepest part of part annular recess 60 and pushed back into the recess 42.

At the same time, the rotation of the handle 38 has caused the protruding portion 72 of the handle pin 70 to rotate through to abut one of the ends 68 of the part annular recess 66. When the protruding portion 72 of the handle pin 70 engages that end 68 further rotation of the handle 38 causes rotation of the plug 14 within the cylinder 12 which in turn rotates the latch 24, allowing the door to be unlocked. It should be noted that the arc of the part annular recess 60 is substantially the same as the part annular recess 66 so that when the second pin mover 40 has moved the locking pin 16 into the unlocked condition any further rotation of the handle 38 immediately causes the rotation of the plug 14 allowing the door to be unlocked.

In figure 5 the second pin mover 40 is shown moved into a position where it is pulling the locking pin 60 out of the locked condition. As described above, this is achieved by rotation of the handle 38. However, figure 5 can be regarded as a schematic representation since this unlocked condition is shown without the handle having been rotated.

Release of the handle 38 causes it to return to its original position under the force of a spring (not shown). The tapered cam surface 62 allows the second pin mover 40 to be pushed back into the deepest part of the part annular recess 60 by the spring 44 which in turn causes the third body portion 54 to sit in the aperture 28 of the locking pin 16 which is pushed back across the shear line 28 by the spring 26. The locking device 10 is once again in the locked condition.

It will be appreciated by persons skilled in the art that the above embodiments have been described by way of example only and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of the protection which is defined by the appended claims. For example, other arrangements are possible for the second pin mover 40 and locking pin 16. By way of example, instead of operating through an aperture in the locking pin 16, the frustoconical cam surface 58 of second pin mover 40 could operate indirectly on the locking pin for example via an arm either fixed to the locking pin or acting via a pivot. The handle 38 is described above as including the tapered cam surface 62. However, the handle 38 could instead be a rotary member which is connected, either directly or indirectly, to another handle which is the part which is grasped by a person wishing to open the door from the inside. In another example, the first pin mover has been described above as a substantially circular cam 30 an asymmetric axis of rotation. However, other cam shapes can work including egg- shaped or elliptical cams with more axes of symmetry which require less than 180° of rotation. Furthermore, in the above embodiment the protruding portion 72 of the pin 70 extends into the part annular recess which is formed in the end portion 64 of the plug 14. However, these components could be reversed with the part annular recess formed in the handle 38 and the protrusion extending from the plug 14.