DEVICE FOR DETECTING MANIPULATION OF AN OBJECT

Abstract

The invention relates to a device (2) for detecting manipulation on an object comprising an actuating switch (22) which has a snap-action disk (220) which can be switched between a first position and a second position, and an actuating element (21) which has a body (210) and an actuating stud (211), projecting from the body of the actuating element (21), for acting on the snap-action disk (220), wherein the actuating stud (211) has a first stiffness. According to the invention a contact element (213), arranged on the actuating stud (211), acts on the snap-action disk (220), wherein the contact element (213) has a second stiffness which is greater than the first stiffness.

Claims

1. A device (2) for detecting manipulation of an object, having an actuating switch (22) which has a snap-action disk (220) which can be switched between a first position and a second position, an actuating element (21) which has a body (210) and an actuating stud (211) which projects from the body of the actuating element (21) and has the purpose of acting on the snap-action disk (220), wherein the actuating stud (211) has a first degree of stiffness, characterized by a bearing element (213) which is arranged on the actuating stud (211) for acting on the snap-action disk (220), wherein the bearing element (213) has a second degree of stiffness which is greater than the first degree of stiffness.

2. The device (2) as claimed in claim 1, characterized in that the actuating element (21) is manufactured from silicone.

3. The device (2) as claimed in claim 1 or 2, characterized in that the actuating element (21) has a rotationally symmetrical basic shape.

4. The device (2) as claimed in one of claims 1 to 3, characterized in that the bearing element (213) is of spherical design.

5. The device (2) as claimed in one of the preceding claims, characterized in that the bearing element (213) is arranged in a receptacle opening (212) which is formed on the actuating stud (211).

6. The device (2) as claimed in one of the preceding claims, characterized in that the bearing element (213) is fabricated from metal.

7. The device (2) as claimed in claim 6, characterized in that the bearing element (213) is fabricated from steel.

8. The device (2) as claimed in one of the preceding claims, characterized in that the snap-action disk (220) has a stable state which corresponds to the first position and a meta-stable state which corresponds to the second position.

9. The device (2) as claimed in one of the preceding claims, characterized in that in a normal position of use of the device the bearing element (213) acts on the snap-action disk (220) and holds the snap-action disk (220) in the second position.

10. The device (2) as claimed in one of the preceding claims, characterized in that manipulation can be detected on the basis of the snapping of the snap-action disk (220) into the first position.

11. The device (2) as claimed in one of the preceding claims, characterized by an evaluation device (23) which is designed to generate an electrical signal on the basis of the position of the snap-action disk (220) and/or of a switching process of the snap-action disk (220) between the first position and the second position.

12. An arrangement (4) having a housing (1) and a device (2) for performing manipulation as claimed in one of the preceding claims, characterized in that the actuating element (21) of the device (2) is arranged on a first housing part (10) of the housing (1), and the actuating switch (22) is arranged on a second housing part (11) of the housing (1).

Description

[0028] The concept on which the invention is based will be explained in more detail below on the basis of the exemplary embodiments illustrated in the figures. In the drawing:

[0029] FIG. 1 shows a schematic view of an arrangement for detecting manipulation of an object having a housing;

[0030] FIG. 2A shows a cross-sectional view through a schematic illustration of a device for detecting manipulation of an object having an actuating switch in a first switch position;

[0031] FIG. 2B shows the device in FIG. 2A in a second switch position;

[0032] FIG. 3 shows a view of an actuating element which includes a body, an actuating stud and a bearing element; and

[0033] FIG. 4 shows a sectional view through the actuating element shown in FIG. 3.

[0034] FIG. 1 shows in a schematic view an arrangement 4 for detecting manipulation of an object having a housing. The object can be, for example, a mobile payment terminal. However, the object can also be, for example, an alarm system, a smoke detector or some other object which is to be protected against unauthorized interventions and has an housing.

[0035] The arrangement 4 includes a housing 1 with at least one first housing part 10 and one second housing part 11. The first housing part 10 can be, for example, a disassemblable housing rear wall or a housing cover. The second housing part 11 can accommodate, for example, a sensitive object such as the control and storage electronics of a mobile bank terminal and can enclose the latter together with the first housing part as a housing 1.

[0036] An unauthorized person could obtain access to the object enclosed by the housing 1 by disassembling the first housing part 10 from the second housing part 11. In this case, it is desirable to detect disassembly of the first housing part 10 from the second housing part 11.

[0037] In order to detect whether the first housing part 10 has been disassembled from the second housing part 11, in the arrangement 4 a device 2 for detecting manipulation of an object is provided which is electrically connected to detection electronics 3 arranged in the second housing part 11, and in the case of disassembly of the first housing part 10 it outputs an electrical signal to the detection electronics 3.

[0038] For this purpose, the device 2 for detecting manipulation of an object includes an actuating element which is arranged on a carrier 20, wherein the carrier 20 is arranged together with the actuating element 21 on the first housing part 10, and an actuating switch 22 which is arranged on an evaluation device 23, wherein the evaluation device 23 is arranged together with the actuating switch on the second housing part 11. The evaluation device 23 can be, for example, a printed circuit board.

[0039] The actuating element 21 and the actuating switch 20 are arranged opposite one another in such a way that in a normal position of use of the device 2, in which the first housing part 10 is mounted on the second housing part 11, the actuating element 21 acts mechanically on the actuating switch 22 and holds it prestressed in a first switch position. The normal position of use of the device 2 for detecting manipulation of an object is in this context that position which the device 2 is in when the object has not been manipulated.

[0040] When the first housing part 10 is disassembled from the second housing part 11, the actuating element 21 is removed from the actuating switch 22, and the actuating switch 22 assumes a second switch position which corresponds to its non-prestressed state. In this context, the evaluation device 23, which can be, for example, a printed circuit board 23 on which the actuating switch 22 is arranged so as to be electrically connected, generates an electrical signal which is passed on to the detection electronics 3. In this context, the detection electronics 3 can also be arranged, for example, directly on the printed circuit board 23.

[0041] The electrical signal can be processed in a variety of ways by the detection electronics 3. For example, the result of the occurrence of the electrical signal can be stored for subsequent reading out, with the result that manipulation can be detected in retrospect. Alternatively, the electrical signal can, however, also directly trigger an alarm or, if the object is an electrical or electronic device, deactivate certain functions of this device.

[0042] In order to permit authorized disassembly, in the arrangement 4 illustrated in FIG. 1 an external interface 30 is provided with the evaluation device 23 and/or the detection electronics 3, via which, for example by inputting a password with a keypad, the generation of the electrical signal can be deactivated or alternatively the processing of the electrical signal can be changed or prohibited.

[0043] FIG. 2A and FIG. 2B show a device 2 for detecting manipulation of an object in a cross-sectionally schematic view. The actuating switch 22 has a snap-action disk 220. The snap-action disk 220 has a stable state which corresponds to a first position of the snap-action disk 220 which is shown in FIG. 2B, and a meta-stable state which corresponds to a second position of the snap-action disk 220 which is illustrated in FIG. 2A. The actuating element 21 has a body 210 and an actuating stud 211 which projects from the body in the direction of the actuating switch 22 and has the purpose of acting on the snap-action disk 220, in order to switch it from a first position into a second position in the case of manipulation of an object. According to the invention, arranged on the actuating stud 211, which has a first degree of stiffness, is a bearing element 213 for acting on the snap-action disk 220 and has a second, greater degree of stiffness.

[0044] An electrical signal can be generated by means of an evaluation device 23 on the basis of the position of the snap-action disk 220 and/or of a switching process of the snap-action disk 220 between the first position and the second position.

[0045] FIG. 2A shows the device 2 for detecting manipulation of an object in a position which corresponds to the normal position of use of the device 2 in the arrangement 4 shown in FIG. 1. In this case, the snap-action disk 220 is prestressed in its second, meta-stable position by action of the bearing element 213. However, the position shown in FIG. 2B can basically also correspond to a normal position of use.

[0046] FIG. 3 shows in relatively large detail the body 210 of the actuating element 21 with the actuating stud 211 and the bearing element 213 in an embodiment in which the actuating stud 211 has a rotationally symmetrical basic shape, specifically conical basic shape. The bearing element 213 in this advantageous refinement is of spherical design and, as can be clearly seen in the sectional view in FIG. 4, is arranged in a receptacle opening 212 which is correspondingly formed in an approximately hemispherical shape.

[0047] The difference according to the invention between the degree of stiffness of the actuating stud 211 and that of the bearing element 213 is implemented in one advantageous embodiment by virtue of the fact that the actuating stud 211 is fabricated from silicone, and the bearing element 213 is a steel ball.

[0048] The advantages of such a refinement of a device 2 for detecting manipulation of an object are explained below.

[0049] When an arrangement 4 is mounted according to FIG. 1, a certain degree of lateral offset can occur within the scope of unavoidable fabrication fluctuations when the actuating element 21 is fastened to the first housing part 10 and/or the actuating switch 22 is fastened to the second housing part 11. For example, the printed circuit board 23 with the actuating switch 22 or the actuating switch 22 can be considered to be shifted a little in the direction marked by V in FIG. 2B on the circuit board 23. In such a case, the tip of the actuating stud 211 and the center of the snap-action disk 220 are not centered one above the other and the force of the actuating element 21 does not act on the snap-action disk 220 precisely perpendicularly with respect to its curved surface.

[0050] This can entail the problem that the snapping over of the disk at the transitions between the stable position and the meta-stable position of the disk takes place when there are snap-over forces which are different from those predefined and which correspond to an ideally centered relative arrangement of actuating switch 22 and actuating element 21. In order to keep this effect small, it is advantageous to fabricate the actuating stud 211 from an elastic material such as silicone so that in the case of non-centered action on the snap-action disk 220 it can correspondingly bend and therefore the force component acting perpendicularly on the curved surface of the snap-action disk 220 becomes as large as possible.

[0051] A spherical bearing element 220 composed of a non-elastic material which is more rigid than the actuating stud 211, such as e.g. steel, acts here in a supporting fashion in the sense of reducing the variation of the snap-over forces, since even when the action on the curved surface of the snap-action disk 220 is not ideally perpendicular, a constantly small contact surface, which is even approximately punctiform in the case of the sphere, is ensured. Therefore, possible fluctuating influences on the snap-over forces which depend on properties of the bearing element 220 are suppressed.

[0052] An elastic actuating stud 220 has the further advantage that, to a certain degree, spring absorption of shocks (due, for example, to transportation) to the housing can occur, with the result that said shocks do not cause the snap-action disk 220 to snap over, and therefore do not bring about a misdiagnosis in terms of supposed manipulation.

[0053] On the other hand, the relatively stiff bearing element prevents an excessively pronounced hysteresis during the switching between the two switch positions of the actuating switch 22 which result from long creeping processes. This would in turn entail an undesirably large influence of properties (possibly subject to fabrication fluctuations or variable environmental influences) of the actuating element 21 on the switching point which is to be set as far as possible solely by means of the snap-action disk 220.

LIST OF REFERENCE SYMBOLS

[0054] 1 Housing [0055] 10 First housing part [0056] 11 Second housing part [0057] 2 Device for detecting manipulation of an object [0058] 20 Carrier [0059] 21 Actuating element [0060] 210 Body of the actuating element [0061] 211 Actuating stud [0062] 212 Receptacle opening [0063] 213 Bearing element [0064] 210 Actuating switch [0065] 220 Snap-action disk [0066] 221 Body of the actuating switch [0067] 23 Evaluation device (printed circuit board) [0068] 3 Detection electronics [0069] 30 External interface [0070] 4 Arrangement for detecting manipulation of an object with a housing [0071] A Triggering direction [0072] V Offset direction