Device for determining the position of two elements moving telescopically relative to one another

Abstract

The invention relates to a device for determining the position of a rod-shaped or tubular first element in relation to a second element which surrounds the first element in the manner of a tube or sleeve, the two elements moving telescopically relative to one another in the longitudinal direction thereof, wherein the position is determined with the aid of an RFID system. In the RFID system, a number of transponders are provided on the first element and an RFID reader in the form of a transceiver with a reader antenna is provided on the second element, each of the transponders having a transponder antenna, and the transponder antennas and the reader antenna being designed for a communication between the RFID reader and the transponders. During the telescoping movement, the transponders pass through the receiving and reading range of the RFID reader and can be activated. An algorithm is stored in a programmable control device which communicates with the RFID reader or is integrated therein, the algorithm determining the position of the RFID reader on the second element relative to the first element from the identification data / position data of the respective activated transponder on the first element. The reader antenna provided on the second element is situated transversely to the telescoping movement and extends at least partly over the circumference of the second element.

Description

[0001] Device for determining the position of two elements moving telescoping relative to each other

[0002] The invention relates to a device for determining the position of a rod- or tube-shaped first element in relation to a second element surrounding the first element in a tube- or sleeve-like manner, wherein both elements move telescopically relative to each other in their longitudinal direction and the determination of the position is carried out using an RFID system in which a number of transponders are provided on the first element and an RFID reader is provided on the second element.

[0003] Devices and systems for determining the position of elements or components moving relative to one another are known. Such systems include, for example, systems that use RFID tags as transponders, which communicate with an RFID reader. The term "RFID tags" is also commonly used for RFID tags, while the term "tag reader" or "RFID reader" is frequently used for an RFID reader.

[0004] For communication with the transponders, the RFID reader is designed as a transmitter-receiver with a reader antenna for transmitting and receiving high-frequency alternating magnetic fields or radio waves. The transponders themselves each have their own transponder antenna. The reader and the transponders contain a number of components and integrated circuits for storing and processing the transmitted information, as well as for modulating and demodulating the high-frequency signals.

[0005] The transponders are attached to one of the moving components or elements and, after activation by the RFID reader, actively or passively transmit a signal containing identification information. This information can be received by the RFID reader connected to the other moving component or element. The identification information can include positional information, i.e., information about the exact position of each transponder on the component, or it can be associated with positional information stored, for example, in the reader's memory in the form of a table, from which the corresponding positional information for each transponder can be retrieved.

[0006] Methods for determining position using RFID systems are technically demanding and require not only interference-free signal transmission but also high reliability and accuracy in position determination. Crucially, this depends on the arrangement, design, and orientation of the antennas and the influence on the propagation characteristics of the high-frequency alternating fields or radio waves.

[0007] EP 3 505 874 A1 discloses a measuring system, in particular an RFID system, for determining a change in position between two moving components during a linear or rotary movement relative to each other. In this system, one or more layers or plates with openings are positioned as apertures between a reader and a transponder. The openings are arranged and dimensioned in such a way that the transmission of transponder signals can be influenced or controlled in order to determine the position of a transponder more accurately from the entire arrangement and multitude of transponders. However, such apertures prove to be unwieldy when using an RFID system to determine the position of two telescoping elements.

[0008] GB 2467185 A discloses an arrangement of a transponder (RFID tag) equipped with an antenna on a cylindrical or elongated circular object. To minimize the influence of the cylindrical object on the transmission characteristics of the transponder antenna, particularly when mounted on a metallic electrical cable, at least parts of the transponder and its antenna are arranged around the circumference of the cylindrical object, especially in a spiral configuration. However, the arrangement disclosed here is less suitable for improving the accuracy of position determination than for preventing changes in the antenna characteristics caused by adjacent metallic objects. Furthermore, each individual transponder or its antenna must be matched, which poses considerable difficulties when dealing with a large number of transponders on telescoping elements.As with all RFID systems, telescoping elements also suffer from the general problem that interference-free signal transmission and accurate position determination can only be guaranteed if the transponders or transponder antennas are within the read and receive range of the reader or reader antenna where the signal strength is sufficient. However, there are applications, particularly with telescoping elements, where the telescoping elements rotate during their linear telescoping movement, so that the very small transponder antennas can easily be "twisted out" of the reader's read and receive range.

[0009] The object of the invention was therefore to provide an RFID system for determining the position of two telescoping elements, which can be implemented in a simple way without extensive assembly and in which sufficient signal strength and high reliability and accuracy in position determination are present even when the telescoping elements rotate against each other.

[0010] This problem is solved according to the features of the main claim, wherein the determination of a position of a rod- or tube-shaped first element in relation to a second element, which surrounds the first element in a tube- or sleeve-like manner, wherein both elements move telescopically in their longitudinal direction relative to each other, is carried out by means of an RFID system in which a number of transponders or RFID tags are provided on the first element and an RFID reader is provided on the second element.

[0011] The RFID reader is designed as a transmitter-receiver with a reader antenna for transmitting and receiving alternating magnetic fields or radio waves within a receiving and reading area of ​​the RFID reader.

[0012] Each transponder has its own antenna, with both the transponder antenna and the reader antenna serving for communication between the RFID reader and the transponder. The RFID reader is attached to the second element and positioned so that the transponders on the first element pass through the RFID reader's reception and read range during their telescoping movement. The transponders can be activated by the RFID reader using alternating magnetic fields or radio waves and are arranged on the first element such that, during the telescoping movement, one or more transponders with their antennas are temporarily within the reception and read range. The arrangement of the transponders on the first element, for example, their spacing from each other, allows for varying degrees of accuracy in position determination.

[0013] The transponders are equipped with an electronic circuit, which, after their activation, allows identification data or identification data and position data of the respective activated transponder on the first element to be transmitted to the RFID reader on the second element.

[0014] A programmable control unit communicating with or integrated into the RFID reader contains an algorithm that determines the relative position of the RFID reader on the second element from the identification data transmitted by the respective activated transponder, or from identification data and position data transmitted by the first element. Since the RFID reader is attached to the second element, the position of the second element relative to the first element is defined by the position of the reader.

[0015] According to the invention, the reader antenna provided on the second element is arranged transversely to the telescoping movement and extends at least partially over a circumference of the second element, in particular such that the radiation from the reader antenna radially to the telescoping movement encompasses the entire circumference and an axial radiation angle along the telescoping movement is minimal.

[0016] With a reader antenna designed in this way and extending at least partially around the circumference, a relative rotation of the two telescoping elements is not critical with regard to signal strength and accuracy in receiving and evaluating the position information of the transponders on the first element. This property is enhanced by a further embodiment of the invention in which the reader antenna extends in a ring shape substantially around the entire circumference of the second element, thus also enclosing the first element. In a further development of the invention, the reader antenna is applied to an outer or inner surface of the second element, which surrounds the first element in a tube- or sleeve-like manner.Such a configuration is easy to produce, especially in combination with a further embodiment of the invention in which the reader antenna is glued to the outer surface or the inner surface of the second element.

[0017] Another embodiment of the invention consists in the reader antenna being applied to a substrate or film, wherein the substrate or film is applied to the outer surface or the inner surface of the second element.

[0018] In a further development of the invention, the reader antenna is embedded in a material of the second element. Various methods are available in the prior art for this purpose, for example an overmould process in which a sleeve-shaped element made of plastic is produced by repeated extrusion with a ring die extruder, and the antenna is placed over the circumference in an intermediate step.

[0019] In another embodiment of the invention, the reading device can be electrically connected to the reading device antenna after the latter has been applied to the second element, e.g. by soldering, electrically conductive adhesive, coatings or other types of contacting.

[0020] In an application of the invention for determining a longitudinal displacement of a piston rod moved telescopically in a cylinder, the device according to the invention is designed such that the longitudinal displacement is determined by repeatedly determining the position of the piston rod as a rod- or tube-shaped first element in relation to the cylinder surrounding the piston rod in a tube- or sleeve-like manner as a second element.

[0021] The RFID reader is permanently connected to the cylinder, and the reader antenna is arranged transversely to the telescoping movement around the circumference of the cylinder, with a number of transponders, which can be activated by the RFID reader using alternating magnetic fields or radio waves, being provided on the piston rod and passing through a receiving and reading area of ​​the RFID reader during the telescoping movement.In a further application of the invention for determining the change in length of a vibration damper in a motor vehicle chassis, the device according to the invention is designed such that the change in length is determined by repeatedly determining the position of an outer damper cylinder, which moves telescopically in a protective cover connected to the damper piston rod and concentrically surrounding an outer damper cylinder, such that the damper piston rod is pressed into the damper cylinder during compression and the damper cylinder plunges into the protective cover surrounding it.

[0022] In this case, an RFID reader is permanently attached to the protective cover, with the reader antenna arranged transversely to the telescoping movement around the circumference of the protective cover. Here, the protective cover is therefore the "second element" within the meaning of the invention.

[0023] On the outer damper cylinder, which is to be understood here as the “first element” within the meaning of the invention, a number of transponders that can be activated by the RFID reader are provided, which pass through a receiving and reading area of ​​the RFID reader during the telescoping movement.

[0024] The invention will be explained in more detail using an exemplary embodiment. The following are shown:

[0025] Fig. 1 shows a simplified schematic diagram of a device according to the invention.

[0026] Furnishings,

[0027] Fig. 2a shows, in principle and as a second element of the device shown in Fig. 1, a sleeve-like element with an RFID reader and an externally arranged reader antenna arranged on its outside.

[0028] Fig. 2b shows, in principle, and as a second element of the device shown in Fig. 1, a sleeve-like element with an RFID reader arranged on its outside and a reader antenna arranged on its inside; Fig. 3 shows, in principle, a reader antenna design according to

[0029] Fig. 2a or 2b in detail,

[0030] Fig. 4 shows a schematic representation of an application of a device according to the invention for determining a change in length of a vibration damper in a motor vehicle chassis.

[0031] The figures may reference identical or similar elements using the same reference numerals. To clarify the invention, it is advantageous to view the figures together.

[0032] Fig. 1 shows in the form of a very simplified schematic diagram a device 100 according to the invention for determining a position of a rod- or tube-shaped first element 101 in relation to a second element 102 surrounding the first element 101 in a tube- or sleeve-like manner, wherein both elements 101, 102 move telescopically relative to each other in their longitudinal direction 103 and the determination of the position is carried out with the aid of an RFID system in which a number of transponders 104 are provided on the first element 101 and an RFID reader 105 is provided on the outside of the second element 102.

[0033] The RFID reader 105 is designed as a transmitter-receiver with a reader antenna 106 for transmitting and receiving alternating magnetic fields or radio waves within a reception and reading range of the RFID reader 105, which is not shown in detail here. The reader antenna 106 is arranged on the outside of the sleeve-like second element 102.

[0034] Each transponder 104 has a transponder antenna, with the transponder antenna and reader antenna 106 serving for communication between the RFID reader 105 and the transponder 104. Transponder antennas are typically integrated on a substrate together with the transponder's integrated circuits within a complex electronic component and are often manufactured as a printed metal wire pattern. Therefore, a detailed description of the transponder antennas is omitted here. Transponders, even those with integrated antennas, can now be manufactured in extremely small sizes in the form of microchips, for example, as so-called p-chips with an area of ​​less than 0.5 mm x 0.5 mm.

[0035] The RFID reader 105 is attached to the second element 102 and arranged such that the transponders 104 on the first element 101 pass through the receiving and reading area of ​​the RFID reader 105 during the telescoping movement.

[0036] The transponders 104 can be activated by the RFID reading device 105 by means of emitted radio waves and are arranged on the first element 101 such that during the telescoping movement in the longitudinal direction 103, one or more transponders 104 together with their transponder antennas are temporarily located within the reception and reading range.

[0037] The transponders 104 are equipped with an electronic circuit (not shown in detail) which, upon activation, allows data from the activated transponder 104 at the first element 101 to be transmitted to the RFID reader 105 at the second element 102. Here, the transponders are configured to transmit identification and position data. In other versions, the transponders' position data can be stored in a table within the reader's memory, from which the corresponding position data / position information for each transponder can be retrieved using the assigned identification data.

[0038] A programmable control unit (not shown in detail here) communicating with or integrated into the RFID reader 105 contains an algorithm that determines the relative position X of the RFID reader 105 at the second element 102 from the identification and position data transmitted by the respective activated transponder 104 at the first element 101. The position data of the transponders refer to an arbitrarily definable reference point B, for example, an endpoint / end of the first element. Starting from such a reference point B, the exact position of the RFID reader 105, and thus the position of the second element 102, can then be determined using the position data of the transponders.

[0039] The reader antenna 106 provided on the second element 102 is arranged transversely to the telescoping movement in the longitudinal direction 103 and extends in a ring shape almost over the entire outer circumference of the second element 102. The radiation of the reader antenna 106 radially to the telescoping movement thus encompasses the entire circumference, while the axial radiation angle along the telescoping movement remains minimal. A rotation 107 of the first element 101 relative to the second element 102 is therefore irrelevant for the accuracy of the position determination and the signal strength of the transmitted / received high-frequency radio waves.

[0040] The arrangement shown in Fig. 1 of a rod- or tube-shaped first element in relation to a second element surrounding the first element in a tube- or sleeve-like manner, in which both elements move telescopically relative to each other in their longitudinal direction, corresponds to an application of the invention for determining a longitudinal displacement of a piston rod moving telescopically in a cylinder, namely by repeatedly determining the position of a piston rod 101 as a rod- or tube-shaped first element in relation to the cylinder 102 surrounding the piston rod 101 in a sleeve-like manner as the second element.

[0041] Figures 2a and 2b show, in principle, a single sleeve-like element 120 of a device according to the invention in two different embodiments. The elements 120 shown in principle in Figure 2 are second elements according to the invention, each of which surrounds a rod- or tube-shaped first element (not shown here).

[0042] The sleeve-like element 120 shown in Fig. 2a has an RFID reader 125 arranged on its outside with a reader antenna 126a, which is also located on the outside of the sleeve-like second element 120.

[0043] In contrast, the sleeve-like element 120 shown in Figure 2b depicts an RFID reader 125 arranged on its outside, with a reader antenna 126b located on the inside of the sleeve-like second element 120. Both embodiments are functionally equivalent and can be used depending on the material of the sleeve-like element 120 and other structural and design conditions.

[0044] Fig. 3 shows, in principle and by way of example, a design of a reader antenna 126, as arranged in Figs. 2a and 2b on the outside or inside of a sleeve-like element 120. A development of the antenna is shown here, in which a meandering arrangement of the antenna 126 is clearly visible.

[0045] Such a design, in conjunction with the ring-shaped extension over the inner or outer circumference of a sleeve-like element, ensures that the radiation from the reader antenna 126 encompasses the entire circumference radially to a telescoping movement 103 and that the axial radiation angle along the telescoping movement 103 is minimal. This allows for precise position determination with good signal strength, regardless of any rotations of either of the two telescoping elements relative to each other.

[0046] The reader antenna 126 is a metallic conductor applied to a substrate or film 127, for example, by an etching process known in the prior art, in which a metallic coating of the film 127 is removed, with the exception of the metallic conductor forming the antenna. The reader antenna 126 is bonded to the substrate on the inner or outer surface of the sleeve-like element.

[0047] Fig. 4 shows in principle a device 200 for determining the position of two telescoping moving elements 201, 202 in a vibration damper 210 for determining a change in length of the vibration damper in a motor vehicle chassis which is not shown in detail here.

[0048] The determination of the change in length is carried out here by repeatedly determining a position of a tubular outer damper cylinder 201 as the first element in relation to a protective shell 202 surrounding the damper cylinder 201 in a sleeve-like manner as the second element.

[0049] The function and design of the vibration damper 210 as such are not the subject of the invention, but are briefly outlined below for a better understanding of the application example of the invention. An exact determination of the change in length, i.e., the compression of such a vibration damper 210, is important for precise chassis control.

[0050] The outer damper cylinder 201 is part of the vibration damper 210, which is designed here as a gas pressure damper, and contains a gas cushion / gas volume 203 above an oil volume 203a. The vibration damper 210, designed as a gas pressure damper, also has an inner damper cylinder 204, in the interior 205 of which an oil volume 205a is located on both sides of a damper piston.

[0051] 206.

[0052] The oil volume 203a of the outer damper cylinder 201 communicates via valves.

[0053] 207 in the base of the inner damper cylinder 204 with the oil volume 205a in the interior 205 of the inner damper cylinder 204. During compression or rebound, the oil volume 205a of the inner damper cylinder 204 also flows via valves 208 in the damper piston 206 from the respective compression side of the damper piston 206 to the opposite tension side. Damping, which will not be discussed in detail here, occurs, in short, through the dissipation of the oil volumes 203a and 205a flowing through the valves 207 and 208 in conjunction with a concomitant compression of the gas volume 203.

[0054] The vibration damper 210 is connected to a mounting point on the body by means of an eye 209 located in its upper part and to a mounting point on the chassis carrier, which is not shown in detail here, by means of an eye 209 located in its lower part.

[0055] The vibration damper 210 has an outer protective cover 202 to protect against stone chips, dirt or other environmental influences.

[0056] Since the protective cover 202 is firmly connected here to a damper piston rod 211 belonging to the vibration damper 210 and concentrically surrounds the outer damper cylinder 201, when the vehicle chassis compresses, the outer damper cylinder 201 and the protective cover 202 surrounding it move telescopically relative to each other in their longitudinal direction 212.

[0057] According to the invention, the repeated determination of the position during a telescoping movement of the outer damper cylinder 201 in relation to the surrounding protective cover 202 is carried out using an RFID system in which a number of transponders 213 are provided on the outer surface of the outer damper cylinder 201 and an RFID reader 214 is provided on the protective cover 202.

[0058] During compression, the outer damper cylinder 201 telescopically extends into the protective sleeve 202, to which the RFID reader 214 is attached. As shown in Fig. 4, a reader antenna 215 is arranged transversely to the telescoping movement on the inner circumference of the protective sleeve 202 and extends in a ring shape almost over the entire inner circumference. Thus, a number of transponders 213, which can be activated by the RFID reader 214 and are provided on the outer surface of the damper cylinder 201, pass through a receiving and reading area of ​​the RFID reader 214 (not shown in detail) during the telescoping movement.

[0059] The activatable transponders 213 are arranged such that during the telescoping movement, one or more transponders 213 with their transponder antennas are temporarily located within the reception and reading range and, after their activation, transmit identification data and position data to the RFID reader 214.

[0060] For repeated position determination or determination of the length change of a vibration damper 210, an algorithm is stored in a programmable control unit (not shown in detail here) that communicates with or is integrated into the RFID reader 214. This algorithm uses the identification and position data transmitted by the respective activated transponder 213 at the outer damper cylinder 201 to determine a relative position X of the RFID reader 214 and thus the position of the protective cover 202. The lower base of the vibration damper is chosen as the reference point B.

[0061] On the left side of Fig. 4, position X1 is shown in the compressed state, and on the right side, position X2 in the extended state of the vehicle chassis or shock absorber. Reference numerals (part of the description)

[0062] 100 Device for determining the position of two telescoping moving elements

[0063] 101 rod- or tube-shaped first element, piston rod

[0064] 102 Second element shaped like a tube or sleeve, cylinder

[0065] 103 Longitudinal direction

[0066] 104 transponders with transponder antenna

[0067] 105 RFID reader

[0068] 106 Reader antenna

[0069] 107 twists

[0070] 120 sleeve-shaped elements

[0071] 125 RFID reader

[0072] 126 Reader antenna

[0073] 126a Reader antenna on the outside

[0074] 126b Reader antenna on the inside

[0075] 127 Substrate or film

[0076] 200 Device for determining the position of two telescoping moving elements of a vibration damper / gas pressure damper

[0077] 201 outer damper cylinder (first element)

[0078] 202 Protective cover (second element)

[0079] 203 Gas volume

[0080] 203a Oil volume

[0081] 204 inner damper cylinder

[0082] 205 Interior of the inner damper cylinder

[0083] 205a Oil volume in the inner damper cylinder

[0084] 206 damper pistons

[0085] 207 valves

[0086] 208 valves

[0087] 209 Eye for fastening

[0088] 210 Vibration damper / gas pressure damper 211 Damper piston rod

[0089] 212 Longitudinal direction

[0090] 213 transponders

[0091] 214 RFID reader

[0092] 215 Reader antenna

[0093] B Reference point

[0094] X Position of the second element 102, 202 relative to the first element 101, 201

[0095] XI position in the compressed state

[0096] X2 position in the extended state

Claims

Patent claims 1. Device (100) for determining a position (X) of a rod- or tube-shaped first element (101, 201) in relation to a second element (102, 202) surrounding the first element in a tube- or sleeve-like manner, wherein both elements move telescopically relative to each other in their longitudinal direction (103, 212) and the determination of the position (X) is carried out by means of an RFID system in which a number of transponders (104, 213) are provided on the first element (101, 201) and an RFID reader (105, 214) is provided on the second element (102, 202), wherein the device has the following features: the RFID reader (105, 214) is configured as a transmitter-receiver with a reader antenna (106, 215) for transmitting and receiving alternating magnetic fields or radio waves within a receiving and Reading area of ​​the RFID reader (105, 214) formed, the transponders (104, 213) each have a transponder antenna, wherein transponder antenna and reader antenna (106,215) for communication between RFID reader (105, 214) and transponder (104, 213), the RFID reader (105, 214) is attached to the second element (102, 202) and arranged such that the transponders (104, 213) on the first element (101, 201) pass through the receive and read area of ​​the RFID reader (105, 214) during the telescoping movement, the transponders (104, 213) can be activated by the RFID reader (105, 214) using alternating magnetic fields or radio waves and are arranged on the first element (101, 201) such that during the telescoping movement one or more transponders (104, 213) with their transponder antennas temporarily move within the receive- and reading area, the transponders (104, 213) are equipped with an electronic circuit whereby, after their activation, identification data or identification data and position data of the respective activated transponder (104, 213) are transmitted to the first element (101 ,201) to the RFID reader (105, 214) on the second element (102, 202) are transferable, A programmable control device communicating with or integrated into the RFID reader (105, 214) contains an algorithm which determines the relative position (X) of the RFID reader (105, 214) on the second element (102, 202) from the identification data or identification data and position data transmitted by the respective activated transponder (104, 213) on the first element (101, 201), characterized in that the reader antenna (106, 215) provided on the second element (102, 202) is arranged transversely to the telescoping movement and extends at least partially over a circumference of the second element (102, 202), in particular such that the radiation from the reader antenna (106, 215) radially to the telescoping movement in the longitudinal direction (103, 212) encompasses the entire circumference and an axial The beam angle along the telescoping movement is minimal.

2. Device according to claim 1, wherein the reader antenna (106, 215) extends in a ring shape over the circumference of the second element (102, 202).

3. Device according to claim 1 or 2, wherein the reader antenna (106, 215) is applied to an outer surface or an inner surface of the second element (102, 202).

4. Device according to claim 3, wherein the reader antenna (106, 215) is glued to the outer surface or the inner surface of the second element (102, 202).

5. Device according to claim 3 or 4, wherein the reader antenna (106, 215) is applied to a substrate or film (127), wherein the substrate or film (127) is applied to the outer surface or the inner surface of the second element (102, 202).

6. Device according to claim 1 or 2, wherein the reader antenna (106, 215) is embedded in a material with which the second element (102, 202) is formed.

7. Device according to one of the preceding claims, wherein the reader (106, 215) can be electrically connected to the reader antenna (106, 215) after the latter has been applied to the second element.

8. Device (100) according to claims 1 to 7, for determining a longitudinal displacement of a piston rod (101) moving telescopically in a cylinder (102), wherein the longitudinal displacement is determined by repeatedly determining a position (X) of the piston rod (101) as a rod- or tube-shaped first element with respect to the cylinder (102) as a second element, which surrounds the piston rod (101) in a tube- or sleeve-like manner, wherein the RFID reader (105) is fixedly connected to the cylinder (102) and the reader antenna (106) is arranged transversely to the telescoping movement in the longitudinal direction (103) over the circumference of the cylinder (102), wherein a number of transponders (104) which can be activated by the RFID reader (105) by means of alternating magnetic fields or radio waves are provided on the piston rod (101), which during the telescoping movement define a reception and reading range of the Passed through RFID reader (105).

9. Device (200) according to claims 1 to 7 for determining the change in length of a vibration damper (210) in a motor vehicle chassis, wherein the determination of the change in length is carried out by repeatedly determining the position of an outer damper cylinder (201), which moves telescopically in a protective cover (202) connected to the damper piston rod (211) and concentrically surrounding the outer damper cylinder (201), such that the outer damper cylinder (201) dips into the protective cover (202) when the suspension is compressed, wherein an RFID reader (214) is fixedly connected to the protective cover (202) and the reader antenna (215) is arranged transversely to the longitudinally (212) telescoping movement over the circumference of the protective cover (202), wherein a number of transponders (213) activatable by the RFID reader (214) are provided on the outer damper cylinder (201), which during the telescoping movement passes through a receiving and reading area of ​​the RFID reader (214).

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