Sensing device for sensing the position of a movable object

Abstract

The invention relates to a sensing device (18) for sensing the position of a movable object comprising: a base (20); an arm (22), which is mounted for rotation relative to the base (20), the arm (22) being rotatable about a first axis of rotation (26) and having a free end (28) for contacting the movable object; and a sensor (24), which is designed to sense rotation of the arm (22) relative to the base (20), the sensor (24) having a first part and a second part. The first part rotates with the arm (22), and the second part is fastened to the base (20). The first part is a first element of a magnet(40)-switch(42) pair, the switch being an electrical switch (42) designed to be actuated by means of the magnetic field of the magnet (40), and the second part is the other element of the magnet(40)-switch(42) pair.

Description

[0001] The present invention relates to a detection device for detecting a position of a moving object and its use.

[0002] The present invention further relates to a system for sterilizing at least one movable object by irradiation, wherein the system comprises at least one conveyor system for transporting the at least one movable object and a detection device.

[0003] In particular, the invention relates to a detection device which is designed to withstand high radioactive radiation, in particular a high gamma dose, and / or high temperatures.

[0004] DE 37 29 303 A1 discloses a switching device with a spring-loaded lever arm. EP 0 843 329 A2 discloses a position switch with a pivoting lever.

[0005] JP S55-171938 U relates to a switch for detecting the passage of a solid object. The switch comprises a frame with a cover containing a reed contact. A lever is rotatably arranged between the frame and the cover. The lever is spring-loaded and includes a magnet for actuating the reed contact.

[0006] Systems for sterilizing objects using radiation, such as medical devices or components, often involve high temperatures and / or high radiation doses. The objects are transported within the system by a conveyor system. Reliable control of the system requires detection of the objects' positions.

[0007] Typically, the positions of objects are detected by detection devices that, by design, have low resistance to high temperatures or high radiation doses. For example, such detection devices often contain a large number of polymer elements that are degraded by sustained radiation. Such detection devices also frequently contain electronic components that are also degraded by sustained radiation. Therefore, it is necessary to frequently replace the known detection devices. This leads to increased maintenance costs.

[0008] Accordingly, it is an object of the present invention to at least reduce or eliminate the above-mentioned disadvantages. In particular, an object of the present invention is to provide a detection device that has high radiation resistance and / or high resistance to high temperatures.

[0009] According to the invention, this object is achieved by a detection device according to claim 1.

[0010] The detection device according to the invention exhibits high resistance to radioactive radiation and high resistance to high temperatures. High radiation resistance and high temperature resistance are achieved, in particular, by the sensor, which comprises the magnet and the electrical switch. The electrical switch is designed to be activated by the magnetic field of the magnet, thus enabling reliable detection of the position of the moving object even under high radiation exposure or high temperatures.

[0011] According to preferred embodiments, the detection device according to the invention is according to any one of claims 2 to 10.

[0012] The invention also relates to the use of a detection device for detecting a position of an object transported in a sterilization plant, the detection device being according to any one of claims 1 to 10.

[0013] The invention also relates to a system for sterilizing at least one movable object by irradiation, the system comprising at least one conveyor system for transporting the at least one movable object and a detection device according to any one of claims 1 to 10, the detection device being configured to detect a position of the transported movable object.

[0014] Preferred embodiments of the invention will now be described in detail with reference to the drawings, in which: Figure 1 is a plan view of a sterilization system comprising several detection devices according to the invention according to an embodiment; Figure 2 is a perspective view of the detection device according to the invention according to an embodiment, and Figure 3 a perspective view of the detection device according to the invention of Figure 2 with a housing, Figure 4 a plan view of the detection device according to the invention of Figure 2 is, and Figure 5 a perspective view of the detection device of the Figure 2 with a horizontal section of the detection device.

[0015] The Figure 1shows a system for sterilizing 1 objects 2 by radiation exposure. The sterilization system 1 comprises a conveyor system 4 for transporting the objects 2 along a conveyor line. The sterilization system 1 comprises one or more radiation sources 6, which are configured to sterilize the objects 2. Each radiation source 6 is configured, in particular, to expose one or more objects 2 to radioactive radiation in order to sterilize the object 2.

[0016] The conveyor system 4 comprises, for example, several floors, for example, two floors. The conveyor system 4 is configured, for example, to transport each object 2 from an entrance 8 along a conveyor line on a first floor, as symbolized in particular by the arrows 10. At a reversing area 12 of the conveyor line, the conveyor system 4 comprises, for example, an elevator 14, which transports each object 2 from the first floor to a second floor. The second floor is arranged, for example, above or below the first floor.

[0017] According to one embodiment, the conveyor system 4 is configured to transport each object 2, starting from the reversing area 12, along a conveyor path on the second floor, as symbolized in particular by the arrows 16.

[0018] Each object 2 is, for example, a sterilization unit which comprises a medical object.

[0019] The sterilization system 1 further comprises one or more detection devices 18.

[0020] The detection device 18 is configured to detect a position of one or more moving objects 2.

[0021] In particular, the detection device 18 is configured to detect a position of the movable object 2 while the movable object 2 is transported along the conveyor path by the at least one conveyor system 4.

[0022] The Figure 2 and 3 show an embodiment of the detection device 18. The detection device 18 comprises a base 20, an arm 22 and a sensor 24.

[0023] In one embodiment, the base 20 comprises a metal plate configured to support the arm 22 and the sensor 24.

[0024] The arm 22 is rotatably mounted relative to the base 20. The arm 22 is rotatable about a first rotation axis 26, in particular between a first rotational position P1 of the arm 22 and a second rotational position P2, as shown for example in Figure 4 The first axis of rotation 26 is in particular orthogonal to a plane encompassing the metal plate of the base 20.

[0025] In the examples of the Figure 2 and 3 the arm 22 is the first rotation position P1.

[0026] The arm 22 has a longitudinal axis 27. The longitudinal axis 27 of the arm 22 in the first rotational position P1 has an angle W between 10% and 90% relative to the second rotational position P2.

[0027] According to embodiments, the shaft 39 has an adjustment device 52. With the adjustment device 52, the arm 22 is adjustable with respect to the shaft 39, in particular the orientation of the arm 22 in a plane perpendicular to the first rotation axis 26. The adjustment device 52 is configured to rotate with the shaft 39. In one embodiment, the adjustment device 52 is configured such that the arm 22 is adjustable with respect to the shaft 39 in uniform steps, for example via a grid 50. For example, the steps can have an angle of between 2 and 20 degrees, in particular between 5 and 15 degrees. In the Figure 3In the example shown, the steps have an angle of 9 degrees. The grid 50 is provided by a gearing. For example, the arm 22 is attached to an inner gear 54 with external teeth. An outer ring 56 with internal gearing is connected to the shaft 39 in a rotationally fixed manner. The external teeth of the inner gear 54 and the internal gearing mesh with each other. The desired grid or step angle can be selected by changing the number of teeth on the external teeth and the internal gearing.

[0028] As described further below, the inner gear 54 can be formed by a shaft portion 60 of the shaft 39 or other means that clearly defines the position of the arm 22 relative to the inner gear 54 or allows the arm 22 to be attached to the inner gear 54 only in a specific direction of rotation. To adjust the (rotational) position of the arm 22, the inner gear 54 is inserted into the outer ring 56 in a corresponding position, and then the arm 22 is placed onto the inner gear 54 according to the specified (rotational) position.

[0029] According to embodiments, the shaft section 60 with the inner gear 54 and outer ring 56 are arranged such that they also rotate about the first axis of rotation 26 when the arm 22 rotates about the first axis of rotation 26.

[0030] Other adjustment devices 52 are also conceivable, for example one or more grooves or projections that interact with the arm 22.

[0031] In particular, triggering of a switch 42 (described below) is adjustable.

[0032] According to variants, the adjustment device 52 is configured to enable a gridless adjustment between 10° and 90°. Thus, for example, the adjustment for triggering / actuating the switch 42 is possible without a grid between 10° and 90°.

[0033] The arm 22 has, for example, a longitudinal opening 29 for mounting the arm 22 on the base 20. The arm 22 is, in particular, displaceable relative to the base 20 in the direction of the longitudinal axis 27. For example, the arm 22 is configured to be displaced in the direction of the longitudinal axis 27 depending on the size of the object 2 and / or the course of the conveying path of the object 2.

[0034] The arm 22 has a free end 28 for contact with the movable object 2. For example, the arm 22 has a roller 30 at the free end 28, which is designed to form a contact point for the movable object 2. The roller 30 has a rotation axis 32 relative to the arm 22. The rotation axis 32 of the roller 30 is, for example, parallel to the first rotation axis 26, as in the embodiment of the Figure 2 and 3 visible.

[0035] In one embodiment, the direction of the rotation axis 32 of the roller 30 can be varied in a plane containing the longitudinal axis 27 of the arm 22 and the first rotation axis 26.

[0036] The detection device 18 is configured, for example, to detect the position of the movable object 2 when it moves in a horizontal direction, and in particular in a horizontal direction orthogonal to the longitudinal axis 27 in the first rotational position P1 of the arm 22. This movement of the detection device 18, for example, configures the arm 22 to be deflected between the first and second rotational positions P1, P2.

[0037] According to the invention, the arm 22 has a first section 34 and a second section 36.

[0038] The first section 34 is rotatably mounted on the base 20. The second section 36 extends the first section 34 by extending from the first section 34 toward the free end 28. The second section 36 is rotatably mounted relative to the first section 34 about a second axis of rotation 38. The second axis of rotation 38 is orthogonal to the first axis of rotation 26, in particular, about the axis of rotation 32 of the roller 30 in the plane containing the longitudinal axis 27 of the arm 22 and the first axis of rotation 26.

[0039] When the second section 36 rotates about the second axis of rotation 38, the roller 30 also rotates and the direction of the axis of rotation 32 of the roller 30 changes.

[0040] For example, the roller 30 is configured to contact the movable object 2. The arm 22 is configured, in particular, to be deflected upon contact with the movable object 2 and to be rotated about the first and / or second rotational axis 26, 38.

[0041] The arm 22 is, for example, configured to perform a multi-axis movement, in particular through the second portion 36, which is rotatable relative to the first portion 34.

[0042] Upon contact with the movable object 2, wherein the movable object 2 moves in a direction that includes a vertical component, the arm 22 is configured, for example, to be deflected in accordance with the movement of the object 2. "Vertical component" is understood to mean a component of a direction parallel to the first axis of rotation 26.

[0043] According to embodiments, the arm 22 is mounted on the base 20 by at least one form-fitting element.

[0044] For example, the arm 22, and in particular the first section 34 of the arm 22, is rotatably mounted on the base 20 via a shaft 39. The shaft 39 is in particular positively connected to the arm 22. For example, the shaft 39 is arranged in a positively locking manner along the longitudinal axis 27 of the arm 22. In particular, the shaft 39 is positively connected to the arm 22 in such a way that the arm 22 is displaceable exclusively in the direction of the longitudinal axis 27.

[0045] According to one embodiment, the shaft 39 has a shaft portion 60, which, for example, comprises the internal gear 54. The shaft portion 60 is particularly suitable for establishing a positive connection between the arm 22 and the shaft 39, as shown, for example, in Figure 5 visible.

[0046] The shaft portion 60 has, in particular, a complementary surface 61 to at least one surface 62, in particular two, preferably parallel, surfaces 62, of the arm 22. For example, the longitudinal opening 29 has the at least one surface 62 on its inner side. The complementary surface 61 forms, in particular, a so-called key surface for the arm 22. In another embodiment, the arm 22 can provide surfaces 62 on its outer side that interact with a corresponding portion of the shaft 39.

[0047] According to one embodiment, the shaft section 60 forms an attachment of the shaft 39, which is positively connected to a shaft 63 of the shaft 39.

[0048] The positive connection between arm 22 and shaft 39 enables a connection without play, so that the detection device 18 functions precisely.

[0049] A positive connection between the arm 22 and the shaft 39 makes it possible, in particular, to meet a requirement of the EN ISO 13849 standard concerning the safety requirements of safety-related parts of control systems. Thus, the detection device 18 is suitable for use as a safety-relevant device.

[0050] The detection device 18 further comprises, for example, at least one bearing (not shown in the figures), in particular two bearings, for supporting the shaft 39 on the base.

[0051] For example, every bearing is a plain bearing, which in particular has a plain bearing bush. For example, every bearing is a dry plain bearing without lubrication.

[0052] The sensor 24 of the detection device 18 is configured to detect a rotation of the arm 22 relative to the base 20 and thus in particular to detect the position of the movable object 2.

[0053] The sensor 24 has a first part and a second part. The first part is arranged to rotate with the arm 22, and the second part is attached to the base 20. For example, the first part is attached to the shaft 39.

[0054] The first part is a first element of a magnet (40)-switch (42) pair, and the second part is the other element of the magnet (40)-switch (42) pair.

[0055] According to one embodiment, the first part is a magnet 40 and the second part is an electrical switch 42. According to an alternative embodiment, the first part is the electrical switch 42 and the second part is the magnet 40.

[0056] The magnet 40 is, in particular, a permanent magnet. According to exemplary embodiments, the magnet 40 is any type of magnet that is a passive component without an intended energy supply and that is configured to generate a magnetic field.

[0057] The electrical switch 42 is configured to be actuated by the magnetic field of the magnet 40. The electrical switch 42 is in a first state when the arm 22 is in the first rotational position P1 and in a second state when the arm 22 is in the second rotational position P2.

[0058] In particular, the axis 39 is in a first predefined position when the arm 22 is in the first rotational position P1, and in a second predefined position when the arm 22 is in the second rotational position P2. The position of the axis 39 is, in particular, independent of an angular fixation of the arm 22 relative to the shaft 39 by means of the adjustment device 52. In the first predefined position, the electrical switch 42 is in the first state, and in the second predefined position, the electrical switch 42 is in the second state.

[0059] The first state is, for example, an "off" state of the electrical switch 42, wherein the electrical switch 42 does not detect the moving object 2. The second state is, for example, an "on" state of the electrical switch 42, wherein the electrical switch 42 detects the moving object 2.

[0060] For example, when the arm 22 is rotated by the angle W, the electrical switch 42 is triggered.

[0061] According to embodiments, the electrical switch comprises a glass tube and a metal contact tongue, for example, an iron-nickel alloy, fused into the glass tube. The contact tongue is configured to be actuated by the magnetic field. The electrical switch 42 comprises, for example, a reed switch.

[0062] The electrical switch 42 is configured, for example, to be connected to a control or monitoring device via ceramic terminals and / or glass-fiber-insulated cables. This allows, for example, the temperature and radiation resistance of the detection device to be further increased.

[0063] According to embodiments, at least the arm 22, the shaft 39, or the bearing are made at least partially of metal. According to one embodiment, both the arm 22 and the shaft 39 and the bearing are made at least partially, preferably entirely, of metal. This particularly increases the resistance of the detection device to radioactive radiation, since the metal is not decomposed by radioactive radiation, for example, unlike polymers.

[0064] According to embodiments, the detection device 18 further comprises at least one return device, in particular a spring (not shown), which is configured to return the arm 22 from the second rotational position P2 to the first rotational position P1.

[0065] According to embodiments, the detection device 18 further comprises a housing 44, which is mounted in particular on the base 20, for example as in Figure 3 shown.

[0066] The housing 44 is designed, in particular, to cover the magnet 40 and the electrical switch 42. The first and second parts of the sensor 24 are thus arranged, in particular, in the housing 44.

[0067] For example, the arm 22 extends in a direction orthogonal to the first axis of rotation 26 beyond an extension of the housing 44 in that direction.

[0068] The detection device 18 is, for example, designed to withstand a gamma dosage of up to 20 kGy / h.

[0069] By "withstanding a gamma dosage of 20 kGy / h" is meant that the detection device 18 is capable of detecting the position of the moving object 2 up to such a dosage.

[0070] The detection device 18 is designed, for example, to permanently withstand a temperature of up to 200°C.

[0071] By "a temperature of at least 200°C permanently" is meant that the detection device 18 is capable of detecting the position of the movable object 2 after such a temperature exposure, in particular after such a temperature exposure for a period of one year.

[0072] The present invention has a number of advantages.

[0073] A movement of the movable object 2 along the detection device 18 causes the rotation of the arm 22 and thus enables the detection of the position of the movable object 2.

[0074] The detection device 18 has a high radiation resistance and / or a high resistance to high temperatures, in particular thanks to the sensor 24, which comprises the magnet 40 and the electrical switch 42, wherein the electrical switch 42 is configured to be actuated by the magnetic field of the magnet 40.

[0075] When using a detection device 18, the detection device 18 detects a position of the movable and / or transported object 2 in a sterilization system 1.

Claims

1. A detection device (18) for detecting the position of a moving object (2), wherein the detection device (18) comprises: - a base (20); - an arm (22) that is mounted rotatable to the base (20), wherein the arm (22) is rotatable around a first rotational axis (26) and has a free end (28) for contact with the moving object (2); and - a sensor (24) that is configured to detect rotation of the arm (22) relative to the base (20), wherein the sensor (24) has a first part and a second part, wherein the first part moves with the arm (22), and the second part is attached to the base (20); Wherein the first part is a first component of a magnet (40) switch (42) pair, wherein the switch is an electrical switch (42) that is configured to be actuated by the magnetic field of the magnet (40), and that the second part is the other component of the magnet (40) switch (42) pair, wherein the electrical switch (42) is in an initial state when the arm (22) is in a first rotational position (P1), and wherein the electrical switch (42) is in a second state when the arm (22) is in a second rotational position (P2) that is different from the first rotational position (P1), and that the detection device (18) comprises a reset device that is a spring, which is configured to move the arm (22) from the second rotational position (P2) into the first rotational position (P1), characterized in that the arm (22) comprises a first section (34) that is mounted rotatable to the base (20), and a second section (36) that extends from the first section (34) in the direction of the free end (28), wherein the second section (36) is mounted rotatable to the first section, wherein the second section (36) is rotatable around a second rotational axis (38) that is orthogonal to the first rotational axis (26).

2. A detection device (18) according to Claim 1, wherein the arm (22) is mounted rotatable to the base (20) by a shaft (39) and at least one bearing, in particular two bearings, wherein each bearing is in particular a sliding bearing.

3. Detection device (18) according to Claim 2, wherein the arm (22), the shaft (39) and the bearing consist of metal.

4. Detection device (18) according to one of the Claims 2 and 3, wherein the first part of the sensor (24) is attached to the shaft (39).

5. A detection device (18) according to any one of the preceding claims, wherein the arm (22) has a roller (30) on the free end (28), wherein the roller (30) is configured to form a contact point for the moving object (2), wherein in particular a rotational axis (32) of the roller (30) is parallel to the first rotational axis (26).

6. A detection device (18) according to one of the previous claims, wherein the detection device (18) is configured to resist a gamma dose of 20 kGy / h.

7. A detection device (18) according to any one of the preceding claims, wherein the arm (22) is mounted to the base (20) by at least one form-fitting component.

8. A detection device (18) according to any one of the preceding claims, wherein the magnet (40) comprises a permanent magnet, and in particular is a permanent magnet.

9. A detection device (18) according to any one of the preceding claims, wherein the electrical switch (42) comprises a reed switch, and in particular is a reed switch.

10. A detection device (18) according to any one of the preceding claims, wherein the first and second parts of the sensor (24) are located in a housing (44) that is mounted on the base (20).

11. Use of a detection device (18) to detect a position of an object transported in a facility for sterilization (2), wherein the detection device (18) is according to one of the preceding claims.

12. Facility for sterilization (1) of at least one moving object (2) by irradiation, wherein the facility has at least one conveyor system (4) for transport of at least one moving object (2) and a detection device (18) according to any one of claims 1 to 10, wherein the detection device (18) is configured to detect a position of the transported moving object (2).

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