|
(11) | EP 0 922 423 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
| (54) | Letterbox assembly |
| (57) Letterbox assembly (1) with an access flap (4) and a security flap (7). The security
flap (7) provides access to a receptacle (2) for items of post (10) and access flap
(4) and security flap (7) are connected to one another via a chute (6). The access
flap (4) and security flap (7) are lockable. Activity on the chute (6), and opening
of the access flap (4) are detected by a radar sensor (13). If activity takes place
for a certain, excessive, time, security measures are taken. These may comprise closing
the security flap (7). |
[0003] Such letterbox assembly is known from French Patent publication 2,478,987. Such letterbox assemblies with an access flap and a security flap are used where, on the one hand, it is necessary to ensure free access to the letterbox, but, on the other hand, abuse cannot be ruled out, i.e. unauthorized persons may attempt to remove post from the receptacle in order to use it for fraudulent transactions. For example, it is known that bank and Giro orders are a particular target for such people, who will try to profit by fraudulent means.
[0004] Structures have been proposed in the prior art in which only either the security flap or the access flap is completely opened. This may be associated with a delay. This is intended to prevent unauthorized access to the post receptacle. However, this measure means that if the access flap is partly opened, the security flap will also be partly opened. As a result, it is possible for undesirables to use wires and the like to fish post out of the receptacle lying beneath the flaps. It is also possible for bars, pipes or the like to be introduced past the security flap in this partially open position, so that when the access flap moves further upwards the security flap is unable to complete its closing movement. Moreover, it is possible for objects or the like to be arranged on the chute in such a manner that post introduced subsequently cannot move further.
[0005] Since banks and similar establishments do not want to be held liable for considerable claims and wish to provide the impression, as far as possible, that they safeguard their customer's details, but, on the other hand, wish to encourage customers to drop off transfer orders directly into letterboxes, the object of the present invention is to provide an improved letterbox assembly in which there is no obstacle to the user posting items, i.e. there is no need for complicated operations using passes and the like, while, on the other hand, it is impossible for people who wish to abuse the system to gain access to the receptacle for post.
[0006] This object is achieved in a letterbox assembly as described above by means of the characterizing features of Claim 1. Abuse can be noted by detecting movement for longer than the normal time. Appropriate measures can be taken, depending on the design. For example, it is possible to close the security flap electrically after a period of, for example, 10-40 seconds, and more particularly 20 seconds, has been exceeded. It is also possible to close the access flap. It is also possible in this way to detect complete closure of the access flap, since if the access flap is almost completely closed, abuse will be possible by introducing a thin foil-like web of material. In order to prevent this type of fraud, it is proposed to monitor whether the access flap is open with the aid of radar means arranged at a distance therefrom. This also allows movement of very thin objects to be detected.
[0007] If, in the event of abuse, it should nevertheless prove possible to hold the security flap open when the access flap is opened, an alarm device may be present which ensures that in such a situation, which is theoretically impossible, an alarm is emitted. This may be a direct visual or acoustic alarm or a silent alarm.
[0008] In order to assist with the movement of items of post and the like along the chute, the latter is provided with projections, so that the contact surface between the chute and such items of post is reduced. If, for example, a wet envelope is inserted, or other wet items of post, adhesion to the chute can be made even less likely by providing ventilator means with an air flow which is such that it can be used to dry items of post which are situated in the upstream part of the chute. If the air flow also moves into the space between the item of post and the base of the chute, in the case of a chute provided with projections, movement of the post can be considerably facilitated.
[0009] If the access flap can be locked electrically, forcing of this locking can be prevented by positioning it slightly deeper in the wall, i.e. downstream of a usual letterbox closure which cannot be locked in any way. In this case, of course, the distance is such that the user can immediately see that his/her post is not moving further if the access flap is closed. A lock of this nature may be important, for example, at the turn of the year and similar occasions.
[0010] According to a further advantageous embodiment, the downstream part of the chute may be protected. This means that sensor means are present in order to check whether there are any objects situated in that area, since in practice it has been found that persons of ill intent block the chute halfway by inserting balls of paper or the like or using adhesive. In such a case, the post will never reach the security flap and, after it has been posted by a well-intentioned user, the defrauder can then remove the post in question from the letterbox assembly simply by opening the access flap. Abuse of this nature can be prevented by employing detection means which cover the chute.
[0011] It is possible that an emergency power supply may be present in order to allow the letterbox assembly to operate securely in the event of a power cut.
[0012] Exemplary embodiments of the invention will be explained in more detail below with reference to exemplary embodiments which are illustrated in the drawing, in which:
Fig. 1 shows a perspective side view, partially in section, of the letterbox assembly according to the present invention, with the access flap closed;
Fig. 2 shows the letterbox assembly in accordance with Fig. 1 with the access flap open; and
Fig. 3 shows a further embodiment of the letterbox assembly according to the invention.
[0013] In Fig. 1, the letterbox assembly according to the invention is denoted by 1. It comprises a receptacle 2 for items of post 10. These items of post 10 can be removed via a door 3. The letterbox assembly is accessible via an access flap 4 which adjoins the conveying section 5. This conveying section 5 comprises a chute 6, at the end of which there is arranged a security flap 7. Moving the security flap 7 into the open or closed position is achieved by means of an actuating magnet 8 which is electrically connected, in a manner which is not illustrated in more detail, to control unit 15.
[0014] A position sensor 9 is also arranged in the vicinity of the security flap 7 in order to detect its position.
[0015] An eye 11, which interacts with a receiver 12, is arranged in the top part of the housing of the letterbox assembly. The signal from this eye is also fed to control unit 15. A radar sensor 13 which is connected to control unit 15 in a manner not illustrated in more detail is also provided. Finally, there is a locking magnet 14 for locking the closed position of access flap 4.
[0016] An emergency power supply 16, such as a battery, is present in the bottom of the housing and, of course, is also connected to control unit 15.
[0017] In the position shown in Fig. 1, the access flap 4 is closed. This is perceived by radar sensor 13 and, starting from the opening movement to the closure movement, security flap A is opened, as shown in Fig. 1, by actuating magnet 8, with a delay of approximately 25 seconds imposed by control unit 15.
[0018] If flap 4 is then opened for the purpose of inserting an item of post (Fig. 2), any movement in the vicinity of the opening of the access flap 4 will in fact be detected by the radar sensor 13. This will immediately activate actuating magnet 8 via control unit 15, thus closing security flap 7. The latter remains closed while the access flap 4 is open, and after the access flap 4 itself has closed, the security flap remains closed for the abovementioned 25 seconds. Then, the security flap 7 is opened and item of post 10 falls into receptacle 2.
[0019] If material, such as balls of paper and the like, accumulates on the chute, this will be detected by the combination of transmission eye 11 and receiver 12. In such a case, an alarm signal is emitted which may be either silent or acoustic and/or visual. In any case, security flap 7 is held in the closed position while this state is present.
[0020] It is also possible that security flap 7 may be opened slightly, by using force or the like, while activity, which is detected by radar sensor 13, is taking place in the vicinity of access flap 4. The position sensor 9 determines whether the security flap 7 is open. If the security flap 7 is open and activity is detected by the radar sensor 13, an alarm signal will be emitted by the intervention of control unit 15.
[0021] During such conditions, and in the absence of the current, it is possible to close the access flap 4 with the aid of locking magnet 14. However, the presence of an emergency power supply feature 16 means that such a state should not occur often.
[0022] Fig. 3 shows a further embodiment of the letterbox assembly according to the invention. The various components are shown in the open position by solid lines and in the closed position by dashed lines.
[0023] The assembly shown in Fig. 3 is denoted overall by 21. The receptacle for post is denoted by the reference numeral 22 and the access part is denoted by 23. The access flap is denoted by 24. Compared to the embodiment shown in Figs. 1 and 2, this access flap is arranged somewhat further downstream, with a freely movable inlet flap 25 positioned upstream. This inlet flap corresponds to a standard letterbox flap and the distance between this inlet flap and the access flap is so small that the user will actually be able to see if the access flap 24 is closed. This makes it more difficult to force access flap 24. The security flap 27 is provided at its end with a magnet 42 which is able to interact with a (reed) contact 43.
[0024] The chute is denoted by 26 and, in this embodiment, is provided with projections or ribs 37 along which the item of post 30 can slide. The base surface 38 is situated between the projections or ribs 37. Toothing 41 is arranged at the end of the chute. The eye described above is denoted by 31 and the receiver which interacts therewith is denoted by 32. Naturally, a number of, for example six, transmitter/receivers of this nature may be present. The radar sensor is denoted by 33 and both the eye or the receiver 32 and the radar sensor 33 are connected to control unit 35. Moreover, a connection is present, in a manner not illustrated in more detail, between locking magnet 34, which actuates the access flap 24 via a system of rods 36, and this control unit 35. A ventilator 39 is present which may optionally run continuously (may, for example, be controlled by radar sensor 33) and which is designed in such a manner that the air flow from it is moved towards the access opening and the immediately adjoining part of the chute. If appropriate, the flow may be such that some of this air moves between an item of post 30 and the space between the ribs or projections 37.
[0025] In the embodiment described here, the control is such that, under "normal" circumstances, both access flap 24 and security flap 27 are opened. If the radar sensor 33 detects activity on the chute 26 for a relatively long time, such as 20 seconds, flap 27 will be closed via control unit 35 and actuating magnet 28. If desired, indicator lamps may be present which show the state of the control unit.
[0026] As can be seen from a comparison of the positions of the rod system 36 (which actuates the access flap 20) which are shown by solid and dashed lines, in the closed position of flap 24 the rod system reaches an "over-centre" position, with the result that exerting a force in the direction of opening the access flap 24 does not lead to a compressive movement on locking magnet 34.
[0027] The transmission/receiving unit 31, 32 is designed in such a manner that if post remains on the chute for a relatively long time, for example for longer than 10 to 15 seconds, the access flap 24 is closed. The security positions described above may be released either automatically, if the insecure state no longer exists, i.e. movement on the chute is no longer observed and/or the item of post has fallen down, or it may be possible that resetting by the user is required.
[0028] It will be clear from the above that numerous variants of the inventive idea are possible. Such amendments and adaptations may be carried out without departing from the scope of the present invention. Such amendments will be immediately obvious to the person skilled in the art on reading the above description and lie within the scope of the appended claims.
1. Letterbox assembly (1, 21) comprising a lockable access flap (3, 23) connected to
a chute (6, 26), which chute ends, at the other side, at a lockable security flap
(7, 27) which provides access to a receptacle (2, 22) for post (10, 30), characterized
in that a radar sensor (13, 33) is arranged in such a manner that movements on the
chute are detected in the vicinity of the access flap (3, 23).
2. Letterbox assembly according to Claim 1, in which said lockable security flap can
be closed electrically by means of actuating means (14, 34) which are connected to
said radar sensor.
3. Letterbox assembly according to Claim 2, in which the actuating means comprise a delay
circuit (15, 35), said security flap being closed a certain time after movement is
detected by said radar sensor.
4. Letterbox assembly according to Claim 3, in which said certain time lies between 10
and 40 seconds.
5. Letterbox assembly according to one of the preceding claims, in which the supporting
surface of the chute comprises projections (37).
6. Letterbox assembly according to one of the preceding claims, in which ventilator means
(39) are present, arranged in such a manner that the air flow from them is directed
towards the supporting surface of the chute.
7. Letterbox assembly according to Claims 5 and 6, in which the air flow is directed
in such a manner that it can move between an object (30) on the chute and the base
(38) of the chute.
8. Letterbox assembly according to one of the preceding claims, in which an inlet flap
(25) is arranged upstream of the access flap (24).