Hanging device

Abstract

Suspension device for protecting an internal device suspended in an outer housing (20) against shocks and vibrations, comprising: an internal device; an outer casing (20); at least one shock-absorbing spring element; a first shelf (105) and a second shelf (105), each shelf (105) being dimensioned to hold a shock-absorbing spring element and being disposed between the inner device and the outer housing (20) and is also positioned outside the shock-absorbing spring element, holding the shock-absorbing spring element in engagement with the inner device; and a connecting element (90) arranged between the first tray (105) and the second tray (105) and fastened to adjacent edges of the first tray (105) and the second tray (105) such that the first tray (105) is positioned parallel to a first axial surface (85) of the inner device and the second tray (105) is positioned parallel to an adjacent second axial surface (85) of the inner device; at least one retaining edge (110) on at least one of the shelves (105), wherein the at least one retaining edge (110) is attached to each side of the shelves (105) which has no other retaining means for the shock-absorbing spring element.

Description

BACKGROUND OF THE INVENTION

[0001] The invention relates essentially to a suspension device for protecting devices mounted in an external housing and, in particular, to a suspension device for a robust radiation detector.

[0002] Radiation detectors typically comprise a light-detecting and quantifying device, such as a photomultiplier tube, and a scintillator element, which can be a crystal or a suitable composition. The scintillator element works by capturing radiation from its surroundings and converting this energy into light. The radiation can be natural ambient radiation or radiation from radiation-emitting material placed near the radiation detector.

[0003] The light generated in the scintillator element by the incident radiation is transmitted through an optical window into the photomultiplier tube. The light pulses are converted into electrical pulses, which are transmitted to a measurement system. Optical connectors are typically used between the scintillator element and the light-detecting element to achieve better light transmission and can also be used to create dynamic separation between the scintillator element and the light-detecting element.

[0004] Portal radiation monitoring has become increasingly important given the current opportunities for the illicit transport of nuclear weapons, radiological ("dirty") bombs, and other illegal radioactive materials. Effective portal radiation monitoring offers a way to detect and prevent the illicit transport and use of these radiation-emitting materials. However, because the means of transport for radioactive materials are diverse, portal monitoring must be applied to a wide range of transportation systems. The types of transport for which portal radiation monitoring must be performed include maritime transport, rail transport, motor vehicles, and people. Consequently, the portal radiation monitoring equipment, which includes radiation detectors, is exposed to a wide variety of environmental conditions.

[0005] Existing portal monitoring radiation detectors are often subjected to varying degrees of shock and vibration during normal use. In some cases, the shock or vibration exposure can be quite severe. It is therefore advantageous to protect the radiation detectors so that they do not suffer damage from shock and vibration. Examples of these effects can include high background counts, noise in the detector's response spectrum, and even detector breakage. Typical methods for protecting these detectors include the use of thick elastomers, foams, etc.

[0006] Existing shock and vibration isolation systems typically consist of either an elastomeric sleeve that is applied around the radiation detector or a foam pad that is wrapped around the radiation detector. Due to the size limitations of portal-monitoring radiation detectors, these methods cannot generally be used. In many cases, the crystal is simply wrapped in a reflective material and then inserted into a 1 mm thick stainless steel housing. The crystal is typically shaped like a 4 x 4 inch (10 cm x 10 cm) rectangle that is 16 inches (40 cm) long. The crystal can also have other shapes, generally including a 2 x 4 inch (5 cm x 10 cm) rectangle that is 16 inches (40 cm) long.

[0007] Typically, soft elastomer materials are used to provide a cushioning effect, and the greater the expected impact, the thicker the elastomer used. This material can be molded into sleeves or sheaths and is achieved by encasing the vibration-sensitive material in an elastomer. Elastomers tend to change shape after significant temperature changes due to their high thermal expansion coefficient or due to high mechanical stress.

[0008] In one such process for manufacturing radiation detectors, a sodium iodide crystal is suspended in a metal casing using a Teflon® sleeve. A Teflon® tape is wrapped around the outside of the scintillator crystal until its dimensions match the interior of the casing. The wrapped crystal is then inserted into the casing.

[0009] Another assembly method uses foam. The sodium iodide must first be surrounded by a reflector to enhance internal photoreflection. The crystal is then inserted into the housing using various systems located inside the waterproof housing. Foam is also used in a shock-resistant scintillation detector according to US 2005 / 0 184 241 A1.

[0010] A larger scintillator element increases the cross-section and thus the probability that a gamma quantum or neutron will enter the element. Likewise, a greater thickness increases the likelihood that the incident radiation will produce scintillation rather than simply passing through the element. Furthermore, the materials surrounding the scintillator crystal can attenuate the incident radiation. The thickness and properties of the protective materials and the housing can adversely affect the device's sensitivity.

[0011] There are numerous patents issued for various types and models of radiation sensors that utilize the suspension systems mentioned above. Another concept for protecting a detector crystal involves the use of metallic leaf springs around the peripheral surface of a cylindrical scintillator crystal. In Frederick et al. (US 5,962,855 A), a radiation detector of approximately cylindrical shape with an axial sidewall constraint surrounding the detector and radial springs placed outside the constraint provides rigid axial and radial constraint. Also in Frederick (US 6,355,932 B1), a first set of elongated radial springs is located around the peripheral surface of a light detector radially between the housing and the light detector, and a second set of similar radial springs is located around the peripheral surface of a radiation detector in which the detectors are cylindrically shaped.These Frederick patents were assigned to General Electric and generally applied to the manufacture and design of cylindrical scintillator detectors for use in oil and gas exploration. However, these patents utilize springs surrounding the entire detector face, partially shielding the detector from the incident radiation it is designed to measure.

[0012] Accordingly, there is a need to provide a robust suspension system to protect the scintillator crystal in a square, rectangular, or other polygonal shape from mechanical shock, vibration, and temperature-induced forces. Furthermore, there is a need to create a suspension system that minimizes the shielding of the detector from the incident radiation it is intended to measure.

[0013] DE 10 2004 042 365 A1 relates to an X-ray detector in which a detector plate is housed in a housing, which has several detector elements arranged in the X and Y directions. To increase robustness, the detector plate is mounted in a floating manner within the housing by means of at least one damping element. BRIEF DESCRIPTION OF THE INVENTION

[0014] The present invention relates to a suspension system for protecting internal equipment in an external enclosure, and more particularly for protecting the elements of a radiation detector assembly mounted in an enclosure from external shock and vibration.

[0015] The present invention relates to a suspension device having the features of claim 1. BRIEF DESCRIPTION OF THE CHARACTERS

[0016] These and other features, aspects and advantages of the present invention will be better understood when the following detailed description is read with reference to the accompanying figures, in which like characters represent like parts throughout, wherein: Fig. 1 is an isometric sectional view of a radiation detector assembly according to one aspect of the present invention; Fig. 2A is a front view of the radiation detector assembly; Fig. Figure 2B illustrates an end view of the radiation detector assembly; Fig. 3 shows an oblique cross-section of the radiation detector component in the radiation detector element; Fig. Figure 4 is an enlarged isometric view of the continuous wave-shaped springs mounted along the edge of a radiation detector element; Fig. Figure 5 is an enlarged view of the suspension provided for a radiation detector element at an axial edge of the element; and Fig. 6 illustrates an exemplary portal radiation monitor employing the radiation detector components of the present invention that utilize a plurality of continuous wave-shaped springs. DETAILED DESCRIPTION OF THE INVENTION

[0017] The previously described methods may not be feasible when attempting to protect a fragile scintillator detector crystal from shock and vibration-induced damage. The following embodiments of the present invention have many advantages stemming from the creation of a compact suspension system that protects the internal devices from the shock and vibration to which an external enclosure is subject. The protected internal devices may vary in function and include gauges, detectors, and other sensitive equipment. The suspension system is particularly suitable for applications where the thickness of the volume between the internal device and the enclosure is limited. The protected internal devices may also have a wide range of shapes and sizes.

[0018] The suspension element may comprise a variety of spring-type devices, including a continuous undulating suspension system. Shocks and vibrations acting on the detector are transmitted through the crystal, so that the crystal moves in synchronization with the detector housing and thus will not impact the housing and cause damage to the crystal.

[0019] An exemplary embodiment of the present invention may relate to the protection of radiation measuring devices. Radiation measuring devices often use scintillator detectors to detect the incident radiation. A typical radiation detector comprises the following components: a scintillator crystal (usually, but not exclusively, thallium-added sodium iodide), a photomultiplier tube (PMT), a housing around each crystal and the PMT, and an optical window and suspension system inside the housing, but not around the outer dimensions of the crystal and the PMT. The thallium-added sodium iodide crystal (NaI(TI)) has been used in radiation detectors since the 1920s and has well-known properties for gamma sensitivity, spectral resolution, and light output. Other scintillator materials may also be used, such as:, but not limited to, cesium iodide (CsI), lanthanum halides (LaHalogenide), etc.

[0020] In an exemplary form, the crystal contains either a rectangular or a square outer dimension as an oblique cross-section. Typical dimensions for these crystals in application as a portal detector can be 2 inches wide x 4 inches deep x 16 inches long or 4 inches wide x 4 inches long x 16 inches long (5 cm x 10 cm x 40 cm or 10 cm x 10 cm x 40 cm). These particular dimensions are not exclusive but represent the general limits that experts have used to date to fabricate radiation detectors for these purposes.

[0021] The invention can be used as a gamma radiation detector. A preferred embodiment of the detector is a gamma radiation detector inside a housing placed near a portal through which people, cars, cargo, or other objects may pass. The unique properties of this detector make it ideal for portals that experience high levels of vibration, such as approaching trains or heavy trucks, and for portable portal monitors that may be shaken or dropped when transported from one location to another. Individual detector element crystals can be used with the individual detector element crystals arranged in a substantially symmetrical arrangement around the periphery of a portal radiation monitor.

[0022] Continuous wave springs typically consist of flat metal strips formed into arcs, forming a continuous wave pattern along the length of the spring. This wave configuration of springs can be placed in the limited space between the radiation detector element and the housing.

[0023] The continuous wave-shaped springs also allow for thermal expansion of the material when the detector is exposed to a wide temperature range. This concept is not limited to sodium iodide. Other scintillator materials such as CsI, La halides, etc. can also be used.

[0024] Furthermore, in various polygonal crystal arrangements, the continuous wave-shaped springs are placed exclusively along the axial edges of the scintillator crystal for axial support. The axial placement of the springs along the edges places less stress on the crystal periphery than the circumferential placement in Frederick. Thus, less material that can act as a shield for the incoming radiation is placed between the external environment being monitored and the crystal, helping to maintain the sensitivity of the scintillator detector.

[0025] A first aspect of the invention provides a suspension system for holding elements in position between an internal device to be suspended and an outer casing. The suspension means comprises at least one shelf, the shelf being sized to hold a spring element and at least one retaining rim, one retaining rim being attached to each side of the shelf that does not have other holding means for the spring element. The suspension means may further comprise a connecting element located between the shelves and attached to the adjacent edge of each shelf to position one shelf parallel to the outer periphery of the internal device to be suspended and a second shelf parallel to an adjacent area on the outer periphery of the internal device.The internal device to be suspended comprises a whole series of elements that can be protected by suspending them in an outer casing comprising a radiation detector element and a light sensing element.

[0026] The suspended device can have many shapes, including a circular oblique cross-section, and can be, for example, a right cylinder. The suspended device can also have a polygonal-shaped cross-section, including a square, a rectangle, and a hexagon. These devices are essentially shaped like straight prisms when used as detector elements. The suspended device can be adapted to many different shapes, including those described above. In an exemplary application where the inner suspended device is a radiation detector element, the suspension device is referred to as a spring guide rail.

[0027] The shelves of the suspension system accommodate the spring elements that mitigate the shock and vibration forces exerted on the outer casing. The spring elements supported against the inner device can comprise continuous wave-shaped springs.

[0028] A plurality of shelves of the suspension device may extend along the axial length of the radiation detector. For a polygonal suspension device with axial edges, a shelf may be positioned on either side of an axial edge of the suspension device. A connecting element may extend outwardly around each axial edge of the suspended device and along the entire length of the axial edge and be attached to each shelf, extending on either side of the associated axial edge. The connecting element may be in the form of a convexly curved loop sized to extend around the axial edge of the suspended internal device.

[0029] Under pressure and release, for example from shock and vibration, the spring element may tend to move laterally from the tray. A plurality of retaining edges may be provided to hold the spring element in the tray and prevent the spring element from sliding off the tray and the associated axial edge. Retaining edges may be provided on each edge of the trays, which have no other retaining means to prevent lateral movement of the spring element. If the trays are positioned on either side of an axial edge of the internal device, the connecting element between the trays may serve as a means to prevent lateral movement of the spring element towards the axial edge, in which case a second retaining edge is not necessary. However, in other applications, a retaining edge may be provided on both edges of the tray.

[0030] The suspension device can be made of formed sheet metal, extruded metal, or an equivalent process. Plastics, ceramics, or other materials may also be advantageous for certain applications.

[0031] According to another aspect of the present invention, a robust radiation detector component is provided. The radiation detector component includes a radiation detector element and a light sensing element operatively connected to the radiation detector element. The radiation detector element may have a square or rectangular oblique cross-section. However, the radiation detector element is not limited to these shapes; it may also include polygonal and circular cross-sections (e.g., hexagonal prisms or cylinders). This component may include a radial suspension system to prevent damage to the fragile scintillator crystal from mechanical shock, vibration, and temperature-induced forces.

[0032] The spring element used for the radiation detector element can consist of continuous undulating metal springs running along the length of the end faces of the scintillator crystal. These continuous undulating springs can be made of any suitable metal or ceramic for the given application. The springs can be coated with Teflon to allow easier movement under thermal expansion and shrinkage and under mechanical shock and vibration. Because the springs fit along the flat surfaces (or tangent edges in the case of a cylinder) of the crystal and are inserted into a housing, they will be subject to a certain degree of compression, which allows them to protect the crystal from shock and vibration.

[0033] The continuous wave-shaped springs can be located on the shelves of the suspension device, which is referred to, for example, as a spring guide rail for the radiation detector element. The spring guide rail can comprise the shelves and a retaining rim on the shelves with outer edges that do not include any further means for retaining the springs. The continuous wave-shaped springs are located along the outer periphery of the radiation detector element radially between the housing and the radiation detector element. The springs can be located axially along any surface of the radiation detector element. For a cylindrical radiation detector element, the springs can be placed all the way around the detector element. For a detector element with a polygonal cross-section and axial edges, the springs can be located adjacent to any axial edge on any surface of the radiation detector element.

[0034] Furthermore, the springs can be placed adjacent to each axial edge and on each side of an axial edge of the radiation detector element. In this arrangement, one spring can be mounted on a tray axially along the surface on one side of the axial edge, and a second spring can be mounted on the tray axially along the surface on the second side of the axial edge of the detector. A connecting element of the spring guide rail can connect the tray edges closest to each axial edge and extend as a convex loop around the edge of the detector, helping to hold the suspension in position at each edge of the detector.

[0035] The radiation detector component will also incorporate an axial suspension system consisting of one or more axial springs attached to the end of the crystal. Compression plates are used on either side of the springs to evenly distribute the load on the springs and the crystal. An axial suspension component is also used around the base of the PMT. In addition to protecting against damage from shock and vibration, the axial suspension helps maintain the optical connection between the crystal, the PMT, and the optical window located between these two components.

[0036] The housing of the radiation detector element can be constructed of a suitable material, preferably thin-walled titanium, aluminum, or steel. The material must not unacceptably attenuate the incident gamma radiation and must also withstand the internal and external forces acting upon it during normal operation. Additionally, with the integration of the suspension system, as described above, the crystal is offset from the housing wall, providing additional protection if the side of the detector housing is compromised in any way. Ultimately, since the crystal is not in close contact with the metal, but instead has a layer of air acting as an insulator between it and the housing, it is unlikely to suffer from thermal shock, as is the case with other similarly constructed detectors.

[0037] Although not illustrated or applied in the above example, the continuous wave springs can also be used to suspend a photomultiplier tube (PMT). The use of the continuous wave springs to protect the PMT is best suited where the available space between an outer surface of the PMT and the inner surface of the PMT housing is limited, with the springs being adapted for use in confined spaces.

[0038] According to another aspect of the invention, a gantry radiation monitor is provided. The radiation detector components, which utilize continuous wave-shaped springs to protect the radiation detector element, can be physically mounted in a support structure to more effectively inspect an object passing through the gantry. The size and orientation of the support structure and the number of radiation detector components used can be based on the exact size and type of object being inspected. Physical mounting to the support structure can utilize symmetrical mounting of a single or multiple radiation detector elements, for example, on the right and left sides and above or below the object being inspected.The detector component connection unit may include means for connecting radiation output signals from each of the plurality of radiation detector components to electronic processing means for processing the radiation output signals from the plurality of radiation detector components. Electronic display means for displaying the radiation output signals from the plurality of radiation detector components may also be provided, along with an alarm that is triggered when the preset radiation levels are reached. The processed radiation signals may also be stored in the data storage means along with other data related to the objects under inspection. Since the means for connecting, processing, displaying, and storing radiation output signals and related information are well known in the art, no further description is necessary.

[0039] Fig. 1 illustrates an isometric sectional view of a radiation detector assembly according to one aspect of the present invention. The radiation detector assembly 10 includes a radiation detector element 15 located within a radiation detector housing 20, an optical window 25 positioned between the radiation detector element 15 and a light detector 27 (photomultiplier tube - PMT) 30 and a PMT housing 35. Optical interconnecting elements (not shown) are also provided between the radiation detector element 15 and the optical window 25 and the photomultiplier tube 30. The radiation detector assembly 10 further includes a reflective material 40 surrounding the radiation detector element 15, a set of spring guide rails 45, and sets of continuous wave-shaped springs 50 at each axial edge of the radiation detector element 15.A connection unit 55 is provided at the end of the radiation detector component 10 opposite the radiation detector element 15 for the PMT 30.

[0040] Fig. 1 further illustrates elements of an exemplary axial suspension system for a radiation detector component 10. A compression plate 60 is provided at the detector end of the radiation detector component and is biased by an axial compression spring 65. A compression plate 70 at the end of the PMT is biased by an axial compression spring 75.

[0041] Fig. Figure 2A illustrates a front view of an exemplary radiation detector component. An oblique cross-section of the radiation detector element end of the component is shown. The connection unit 55 is provided with connectors 57 for receiving a radiation output signal from the PMT ( Fig. 1, Fig. 30) to an electronic system for processing and displaying the signal (not shown). The PMT housing 35 closes the PMT tube end of the component, which includes the terminal unit 55, the PMT tube, the optical window, the pressure plate, and the axial compression spring ( Fig. 1) includes. Fig. Figure 2B shows an end view of the radiation detector assembly including the connector unit 55 with the plugs 57.

[0042] Fig. 3 illustrates an oblique cross-section of an exemplary radiation detector component on the radiation detector element. The exemplary radiation detector element 15 is illustrated with a rectangular cross-section. The radiation detector element 15 is surrounded by the reflective material 40. A spring guide rail 45 is located at each axial edge 90 of the radiation detector element 15. Two continuous wave-shaped springs 50 are compressed between each spring guide rail 45 and the radiation detector housing 20.

[0043] Fig. Figure 4 illustrates an enlarged isometric view of the continuous wave springs mounted along the edge of a radiation detector element. The continuous wave springs 50 are shown on the surfaces 85 of the radiation detector element 15 adjacent to the edge 90 of the radiation detector element 15. A continuous wave spring 50 having a width W and a length L is located in each shelf 105 of the spring guide rail 45. The edges 110 prevent the continuous wave spring 50 from slipping off the shelf when it undergoes compression and relaxation.

[0044] Fig. Figure 5 illustrates an enlarged view of the suspension provided for a radiation detector element at one axial edge of the element. A radiation detector element 15 wrapped in reflective material 40 is surrounded by a radiation detector housing 20. The gap 80 between the radiation detector element 15 and the radiation detector housing is maintained by the spring guide rail 45 and the continuous wave-shaped springs 50. The spring guide rail 45 includes two shelves 105, one on each surface 85 ( Fig. 4) of the radiation detector element adjacent to the axial edge 90 of the radiation detector element 15. Each shelf is wide enough to cover the width W ( Fig. 4) of the continuous wave-shaped spring 50 and extends nominally over the entire length of the axial edge 90 of the radiation detector element 15, and long enough to cover the length L ( Fig. 4) of the continuous wave-shaped spring 50. Each shelf 105 is attached at its inner corner 95, closest to the axial edge 90 of the radiation detector element 15, to a convexly curved loop 100 located between the shelves 105. The convexly curved loop 100 extends the entire length of the spring guide rail 45. Retaining rims 110 are attached to the outer corners of the shelves 105. Each retaining rim 110 forms an angle of approximately 45 degrees with respect to its associated shelf 105.

[0045] While the exemplary radiation detector element is shown as having a rectangular cross-section, the suspension system may be used in conjunction with a polygonally shaped detector wherein the spring guide rail is adjustable to align with the shelves and thus the continuous wave-shaped springs are flush with the surfaces of the detector element that border the common edge of the radiation detector element.

[0046] Furthermore, the spring guide rail can be adapted to cylindrical radiation detector elements. For cylindrical detector elements, a single tray with retaining rims at both corners can be used to support the continuous wave-shaped springs around the detector along the axial tangent to the cylinder and radially between the detector and the housing. Furthermore, the spring guide rails can also be provided with double trays connected by an appropriately shaped connecting piece to adapt the trays to the curvature of the cylinder. In the cylindrical detector application, retaining rims can be formed at the corner of each tray that is not already otherwise provided with a spring retaining means.

[0047] Fig. 6 illustrates an exemplary gantry radiation monitor that utilizes radiation detector components comprising a plurality of continuous wave-shaped springs 50 located radially along the outer periphery of the light detector element between the radiation detector housing 20 and the radiation detector element 15. The gantry radiation monitor 150 utilizes a plurality of radiation detector components 170 mounted on a support structure 160. The support structure 160 has the size and shape of the objects to be inspected. Multiple radiation detector components 170 can be placed at physical locations on the support structure 160 to best capture the emitted radiation based on the type of objects passing through the gantry space 180 of the gantry radiation monitor 150. The exemplary arrangement of the radiation detector components 170 in Fig.6 is symmetrical with respect to the portal space 180 through which the objects to be inspected pass. The portal space 180 may be sized to inspect personal items such as luggage, motor vehicles, trucks, freight containers, trains, or any objects to be inspected for radiation emissions. A connection means 190 is provided to connect the radiation detector output signals 200 from the individual radiation detector components 170 to an electronic processing means 210. The electronic processing means 210 may provide a processed radiation signal 220 to a display means 230 and to an alarm 240. A data storage means 250 may be used to store the processed radiation signals 250 and other information elements (not shown) related to the objects being inspected.

[0048] A radiation detector component 10 is provided. The radiation detector component 10 includes a radiation detector element 15 and a light detection element 27 that are operatively connected. The radiation detector element 15 is located inside a radiation detector housing 20. The radiation detector component 10 further includes a plurality of continuous wave-shaped springs 50 located radially along the outer periphery of the radiation detector element 15 between the housing 20 and the radiation detector element 15.

[0049] While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. Therefore, it should be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. List of reference symbols 10 Radiation detector component 15 Radiation detector element 20 radiation detector housings 25 optical window 27 Light detector element 30 photomultiplier tubes 35 photomultiplier housings 40 reflective material 45 spring guide rail 50 continuous wave-shaped springs 55 connection unit 60 detector pressure plate 65 axial compression spring 70 Photomultiplier printing plate 75 axial compression spring 80 axial edge 85 axial surface 90 connecting element 95 exterior area 100 convex curved edge 105 filing 110 retaining edge 115 Storage edge 120 cross section 150 Portal Monitor 160 support structure 170 detector component 180 inspection room 190 lanyards 200 Radiation detector component output signal 210 processing agents 220 processed radiation signals 230 display devices 240 Alarm 250 data storage

Claims

[1] Suspension device for protecting an internal device suspended in an outer housing (20) against shocks and vibrations, comprising: an internal device; an outer casing (20); at least one shock-absorbing spring element; a first shelf (105) and a second shelf (105), each shelf (105) being dimensioned to hold a shock-absorbing spring element and being disposed between the inner device and the outer housing (20) and is also positioned outside the shock-absorbing spring element, holding the shock-absorbing spring element in engagement with the inner device; and a connecting element (90) arranged between the first tray (105) and the second tray (105) and fastened to adjacent edges of the first tray (105) and the second tray (105) such that the first tray (105) is positioned parallel to a first axial surface (85) of the inner device and the second tray (105) is positioned parallel to an adjacent second axial surface (85) of the inner device; at least one retaining edge (110) on at least one of the shelves (105), wherein the at least one retaining edge (110) is attached to each side of the shelves (105) which has no other retaining means for the shock-absorbing spring element. [2] A suspension device according to claim 1, wherein the connecting element (90) comprises a convexly curved loop (100) extending around an axial edge (90) of the inner device. [3] Suspension device according to claim 2, wherein the shock-absorbing spring element comprises continuous wave-shaped springs (50). [4] A suspension device according to claim 3, wherein the internal device comprises a radiation detector element (15). [5] Suspension device according to claim 4, further comprising: a plurality of shelves (105) extending over an axial length of the radiation detector element (15), the first shelf (105) being arranged on the first axial surface (85) of the radiation detector element, adjacent to the axial edge (90), and the second shelf (105) being arranged on the second axial surface (85) of the radiation detector element, adjacent to the same axial edge; wherein the connecting element (90) extends outwardly around the axial edge (90) of the radiation detector element (15) and forms a connection between an adjacent edge of the first tray (105) and an adjacent edge of the second tray, the connection extending substantially along the axial edge (90) of the radiation detector element (15); and a number of retaining edges (110), wherein a first retaining edge (110) is arranged on an edge of the first tray (105) outside the connecting element (90) and a second retaining edge (110) is arranged on an edge of the second tray (105) outside the connecting element (90), whereby the continuous wave-shaped springs (50) are prevented from sliding out of the tray (105) and away from the associated axial edge (90). [6] Suspension device according to claim 5, wherein the cross-section of the radiation detector element (15) is circular. [7] Suspension device according to claim 5, wherein the cross-section of the radiation detector element (15) is polygonal. [8] Suspension device according to claim 5, wherein the cross-section of the radiation detector element (15) is rectangular. [9] Suspension device according to claim 5, wherein the continuous wave-shaped springs (50) comprise formed sheet metal. [10] A suspension device according to claim 5, wherein the continuous wave-shaped springs (50) comprise extruded metal.

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