Manhole cover, manhole covering and monitoring system

Abstract

The invention relates to a manhole cover (10) for a manhole covering (50) comprising at least one locking device (20) for locking the manhole cover (10) on a manhole frame (40) of the manhole covering (50), wherein the locking device (20) has a lock (21), which can be moved between an unlocking position (I) and a locking position (II), and a monitoring device (30) for monitoring the locking, wherein the lock (21) can be moved from the locking position (II) into a pressing-on position (III) in order to press the manhole cover (10) firmly onto the manhole frame (40) in use, wherein the monitoring device (30) is designed to detect the unlocking position (I), the locking position (II) and the pressing-on position (III) of the lock (21).

Description

[0001] Manhole cover, manhole cover and monitoring system

[0002] DESCRIPTION

[0003] The invention relates to a manhole cover for a manhole cover according to the preamble of claim 1. Furthermore, the invention relates to a manhole cover with such a manhole cover and a monitoring system with such a manhole cover. A manhole cover of the type mentioned above is known, for example, from EP 1 867 791 B1.

[0004] To cover underground shafts, manhole covers are generally used, which are inserted into a manhole frame. Used on racetracks, such as Formula 1 racetracks, such manhole covers are subjected to extraordinary stresses. Due to the special design and high driving speeds of racing cars, a vacuum is created between the car's underbody and the racetrack, which can suck in the manhole cover to such an extent that it is lifted by the manhole frame and thrown upwards, for example, onto an opposing race car. This can lead to serious accidents, often associated with a high health risk for the drivers.

[0005] For this reason, such manhole covers are usually secured to the manhole frame before the race by welding, screwing, or locking them. These locking devices are manually checked by service personnel in a separate step. However, the manual inspection of each individual locking device is error-prone and time-consuming. Furthermore, it has been found that the high loads can cause weld seams to break and mechanical locking devices to release themselves, for example, due to vibrations when driving over them. EP 1 867 791 B1 discloses a manhole cover with a latch and a monitoring device. In the locked position, the latch engages with a manhole frame, thereby preventing the manhole cover from being lifted. The monitoring device monitors the latch and communicates the locking status to a monitoring center.While this method directly notifies the service personnel in the monitoring center about an unsecured manhole cover, allowing immediate intervention, the unsecured manhole cover poses a significant danger to the racing cars and, in particular, to the drivers until the service personnel actually intervene.

[0006] The object of the present invention is therefore to improve a manhole cover of the type mentioned above in such a way as to increase safety. Furthermore, the invention is based on the object of providing a manhole cover with such a manhole cover and a monitoring system with such a manhole cover.

[0007] According to the invention, this object is achieved by a manhole cover according to claim 1 and a manhole cover according to claim 11 and a monitoring system according to claim 13.

[0008] Specifically, the object is achieved according to the invention by a manhole cover for a manhole cover. The manhole cover comprises at least one locking device for locking the manhole cover to a manhole frame of the manhole cover, wherein the locking device has a latch that is movable between an unlocked position and a locked position. The manhole cover further comprises a monitoring device for monitoring the locking. The manhole cover is characterized in that the latch is movable from the locked position into a pressing position in order to press the manhole cover firmly against the manhole frame during use, wherein the monitoring device is designed to detect the unlocked position, the locking position, and the pressing position of the latch.

[0009] The invention is based, on the one hand, on the idea of ​​providing a manhole cover that can not only be locked by means of the latch, but can also be firmly pressed against the manhole frame. For this purpose, the latch is designed to be movable between the unlocked position, the locked position, and the pressing position, with the latch moving from the locked position to the pressing position by being pressed against the manhole frame.

[0010] By firmly pressing the bolt in the clamping position against the shaft frame, the contact force between the bolt and the shaft frame, as well as between the shaft cover and the shaft frame, is increased. This reduces the risk of the bolt moving independently into the unlocked area against this contact force. The contact force also reduces the freedom of movement of the shaft cover, shaft frame, and bolt relative to each other, further reducing the risk of the locking mechanism unlocking independently, for example, due to vibrations when driving over it. Furthermore, the distance the bolt must travel to reach the unlocked area is extended by the clamping position, further increasing security.

[0011] The invention is based on the further idea that the monitoring device for monitoring the locking mechanism detects the pressing position, the locking position, and the unlocking position of the bolt. Thus, during use, the monitoring device automatically detects whether the bolt is pressing the manhole cover firmly against the manhole frame, merely locking the manhole cover to the manhole frame, or not securing it at all. This allows the monitoring device to communicate the position of the bolt, and thus the security status of the manhole cover, to a monitoring center, for example, to inform service personnel.

[0012] The monitoring device thus detects the bolt's transition from the closed position to the locked position, allowing intervention before the bolt moves from the locked position into the unlocked area. This further reduces the risk of the bolt unlocking itself.

[0013] A manhole cover according to the invention is designed for use with a manhole frame in manhole covers on racetracks, for example, Formula 1 racetracks. The manhole cover can also be used in other manhole covers. It is also possible to use the inventive concept without a manhole frame and generally in connection with the covering of manholes or the like. Preferred embodiments of the invention are given in the subclaims.

[0014] In a preferred embodiment of the invention, the locking device comprises at least one screw that can be actuated from the outside of the manhole cover and, during use, moves the bolt between the locking position and the pressing position. The screw allows the bolt, and thus the manhole cover, to be pressed particularly firmly against the manhole frame, for example using an appropriate tool. The positive locking and the self-locking action of the screw thread hold the bolt firmly in the pressing position and additionally counteract the automatic unlocking of the lock. Since the screw can be actuated from the outside of the manhole cover, the bolt can be moved particularly easily and quickly between the locking position and the pressing position, for example by service personnel using an appropriate tool.

[0015] The screw is preferably designed to move, in particular pivot, the bolt between the unlocked and locked positions. Since the screw simultaneously causes the bolt to move between the unlocked and locked positions, additional means for transmitting movement to the bolt are eliminated. This simplifies the construction of the manhole cover and reduces the effort required by service personnel, as the tool for operating the screw only needs to be applied once. To further simplify the construction, the bolt is designed to pivot between the unlocked and locked positions, so that the rotational movement of the screw is directly transmitted to the bolt.

[0016] The locking device preferably has a stop, in particular an angle stop, for the bolt in the unlocked position and in the locked position. The stops ensure that the bolt assumes the unlocked and locked positions precisely. Errors in the detection of the bolt positions by the monitoring device are thus reduced, thus increasing safety. Particularly preferably, the stop for the bolt in the locked position simultaneously also forms a stop for the bolt in the contact position, in order to ensure precise positioning of the bolt in the contact position. To increase the contact force between the manhole cover and the manhole frame, it is advantageous if the manhole cover has at least two, preferably three, locking devices.

[0017] To improve the contact pressure between the manhole cover and the manhole frame, the locking devices are preferably distributed along the circumference of the manhole cover, in particular evenly distributed. The contact pressure is thus distributed over the circumference, so that the manhole cover is pressed firmly against the manhole frame from all sides.

[0018] To detect the position of the bolt particularly reliably, it is advantageous if the monitoring device has at least one sensor, in particular an inductive sensor, preferably a Hall sensor, for detecting the position of the bolt. An inductive sensor measures the change in position of the bolt, thus also detecting positions of the bolt between the unlocked position, the locked position, and the contact position during use. The reliability of detecting the bolt position can be further increased in this way.

[0019] The monitoring device preferably has an antenna, particularly a ceramic antenna, for wirelessly transmitting information about the position of the bolt to a monitoring center. This eliminates the need for communication lines, which are complex to install and maintain. However, since the antenna can be installed and removed quickly and easily, it reduces the effort required for installation and maintenance. The probability of errors during these steps is thus also reduced.

[0020] It is advantageous if the monitoring device has at least one energy storage device for a self-sufficient energy supply. Since the energy storage device makes power lines obsolete, the effort required for installation and maintenance can be further reduced. Furthermore, the energy storage device can be installed only when needed and then removed again, whereas power lines are permanently exposed to environmental influences. This advantageously reduces the risk of power supply failure. In a preferred embodiment of the invention, the monitoring device is arranged in a protected housing on the inside of the manhole cover. The housing protects the monitoring device from environmental influences and thus reduces its risk of failure.

[0021] A secondary aspect of the invention relates to a manhole cover with a previously described manhole cover and a manhole frame for receiving the manhole cover, wherein the manhole cover rests on a support surface of the manhole frame.

[0022] Thus, both the combination of manhole cover and manhole frame, as well as the manhole cover itself, i.e., independently of the manhole frame, are disclosed and claimed. Regarding the effect and advantages of the manhole cover, reference is made to the explanations in connection with the manhole cover. The above-described developments of the manhole cover are therefore also disclosed in connection with the manhole cover.

[0023] In a preferred embodiment of the manhole cover, the bolt of the locking device engages behind the manhole frame, in particular a projection of the manhole frame, in the locking position and presses against the manhole frame, in particular the projection of the manhole frame, in the pressing position, so that the manhole cover is pressed firmly against the support surface of the manhole frame.

[0024] A further, subordinate aspect of the invention relates to a monitoring system comprising at least one manhole cover as described above and a monitoring center. The monitoring center is configured to receive information about the position of the locking bar from the monitoring device and to visualize the position of the locking bar.

[0025] For the effect and advantages of the monitoring system, please refer to the explanations in connection with the manhole cover and the manhole cover. The invention is explained in more detail below using exemplary embodiments with reference to the attached schematic drawings. In these drawings:

[0026] Fig. 1 shows a cross section of a manhole cover with a manhole cover according to an embodiment of the invention;

[0027] Fig. 2 is a plan view of the manhole cover from Fig. 1;

[0028] Fig. 3 shows a visualization of locking positions and securing states of a manhole cover provided by a monitoring system according to an embodiment of the invention;

[0029] Fig. 4 shows a visualization of secured manhole covers on a race track provided by a monitoring system according to an embodiment of the invention;

[0030] Fig. 5 is a detailed view of a locking device of the manhole cover from Fig. 1, wherein a latch of the manhole cover is in the pressing position;

[0031] Fig. 6 is a detailed view of a locking device of the manhole cover from Fig. 1, wherein the latch of the manhole cover is in the locking position;

[0032] Fig. 7 is a detailed view of a locking device of the manhole cover of Fig. 1, wherein the latch of the manhole cover is in the unlocking position; and

[0033] Fig. 8 shows the visualization from Fig. 4, where a manhole cover is unsecured.

[0034] The attached figures show a preferred embodiment of a manhole cover 10 for a manhole cover 50 on racetracks, specifically Formula 1 racetracks. However, the invention can also be used for other purposes.

[0035] Specifically, Figs. 1 and 2 as well as 5 to 7 show a manhole cover 50 with the manhole cover 10 and a manhole frame 40, wherein the manhole cover 10 rests on a support surface 41 of the manhole frame 40. The manhole cover 10 comprises a monitoring device 30 and three locking devices 20 evenly distributed over the circumference. The manhole cover 10 can also comprise several monitoring devices 30, as well as only one locking device 20, or two or more than three locking devices 30.

[0036] Fig. 1 shows a cross-section of the manhole cover 50 through one of the three locking devices 20. Each locking device 20 has a respective latch 21.

[0037] To lock the manhole cover 10 to the manhole frame 40 and to release this locking, the latch 21 is movable between an unlocking position I and a locking position II. To also press the manhole cover 10 firmly against the manhole frame 40 during use, the latch 21 is movable from the locking position II to a pressing position III.

[0038] Fig. 1 shows the latch 21 in contact position III. The latch 21 forms an integral assembly with the manhole cover 10, with the latch 21 being arranged on an inner side 12 of the manhole cover 10. In locking position II and in contact position III, the manhole frame 40 is arranged between the manhole cover 10 and the latch 21. The latch 21 thus engages behind the manhole frame 40 in both locking position II and contact position III.

[0039] In pressing position III, the bolt 21 presses against the shaft frame 40. Since the bolt 21 and the shaft cover 10 form an integral assembly, the shaft cover 10 is pressed firmly against the shaft frame 40, specifically against the support surface 41 of the shaft frame 40, by the pressing force of the bolt 21 in pressing position III.

[0040] To monitor the locking mechanism during use, for example, during a race, the monitoring device 30 is designed to detect the unlocking position I, the locking position II, and the pressing position III of the bolt 21. The monitoring device 30 thus monitors the locking mechanism during use by automatically detecting the position of the bolt 21 and communicating this to a monitoring center. Since a transition of the bolt 21 from the pressing position III to the locking position II is detected and communicated, intervention, for example by service personnel, is possible even before the bolt 21 moves from the locking position III into the dangerous, unlocked area.

[0041] The locking device 20 has a screw 22 that can be actuated from an outer side 11 of the manhole cover 10. The screw 22 is inserted from the outer side 11 through a through-hole in the manhole cover 10 and protrudes from the through-hole with its screw thread on the inner side 12 of the manhole cover 10. The bolt 21 is screwed onto the protruding portion of the screw 22. For this purpose, the bolt 21 has a through-hole with an internal thread that forms a positive connection with the screw thread.

[0042] In use, the screw 22 moves the latch 21 between the locking position II and the pressing position III. For this purpose, the screw 22 is actuated from the outside 11 using a suitable tool. In this way, the latch 21 can be pressed firmly against the shaft frame 40 by tightening the screw 22, i.e., moved from the locking position II to the pressing position III. To move the latch 21 from the pressing position III back to the locking position II, the screw connection between the screw 22 and the latch 21 is loosened again.

[0043] The screw 22 is adapted to move, in particular pivot, the bolt 21 between the unlocking position I and the locking position II. Specifically, when the screw 22 is actuated between the unlocking position I and the locking position II, the bolt 21 rotates with the screw 22 due to the positive engagement between the bolt 21 and the screw 22.

[0044] The bolt 21 thus forms a sash or screw sash which can be pivoted between the unlocking position I and the locking position II and can be moved by screws between the locking position II and the pressing position III.

[0045] The locking device 20 has a stop, in particular an angle stop, for the bolt 21 in the unlocking position I and in the locking position II. The stops are arranged offset from one another by approximately 90° with respect to the axis of the screw 22. The stop for the bolt 21 in the locking position II simultaneously also forms a stop for the bolt 21 in the pressing position III. The bolt 21 has a projection 23 designed to interact with the stops to transmit force in the unlocking position I, the locking position II, and the pressing position III.

[0046] The stops thus limit the pivoting movement of the bolt 21 between unlocking position I and locking position II. If the screw 22 is actuated or turned so that the bolt 21 is pivoted from the unlocking position I towards the locking position II, the bolt 21 hits the respective stop in the locking position II so that it exactly assumes the locking position II. Since a continuation of the pivoting movement of the bolt 21 in this direction is prevented by the stop, upon further turning of the screw 22 the bolt 21 is screwed towards the shaft cover 10 into the pressing position III. The movement of the bolt 21 from the pressing position III via the locking position II into the unlocking position I takes place analogously.

[0047] The monitoring device 30 has a sensor 31, specifically an inductive sensor, for example a Hall sensor. The sensor 31 is configured to detect a magnet 35 and identify its position or location. For this purpose, the sensor 31 is arranged on the inner side 12 of the manhole cover 10 such that its position relative to the manhole cover 10 does not change when the latch 21 is adjusted or moved. The magnet, however, is arranged on the latch 21, so that when the latch 21 is moved, the magnet 35 is also moved.

[0048] During use, sensor 31 measures the change in inductance or its quality due to a change in position relative to magnet 35. During use, latch 21, and thus magnet 35, always assumes the same position relative to sensor 31 in unlocking position I, locking position II, and contact position III. The measurement result is therefore known in advance in latch positions I, II, III, so that detection of these latch positions I, II, III is possible. Based on the same principle, sensor 31 also detects positions of latch 21 between the previously known latch positions I, II, III.

[0049] Other sensors can be used as long as the unlocking position I, the locking position II and the contact pressure position III are detected.

[0050] The monitoring device 30 has an antenna 32, specifically a ceramic antenna 32. The antenna 32 is arranged centrally on the inner side 12 of the manhole cover 10 such that the distance to the outer side 11 of the manhole cover 10 is minimal. The use of other antennas and their arrangements is possible.

[0051] During use, the signal from sensor 31, i.e., the information about the position of the latch 21, is wirelessly transmitted to the monitoring center via the antenna 32. The short distance to the outer surface 11 reduces the shielding effect of the manhole cover 10, thus stabilizing the signal transmission from the antenna 32 through the manhole cover 10 to the monitoring center. Signal transmission via cables, such as communication lines, is also possible.

[0052] The signal from sensor 31 is processed for signal transmission by electronics 36 of monitoring device 30. Specifically, electronics 36 converts the signal from sensor 31 into an NB-IoT (Narrowband Internet of Things) signal, so that, for example, the racing car radio is not disrupted by the signal transmission.

[0053] The monitoring device 30 has an energy storage device 33 for a self-sufficient energy supply. In the embodiment shown, the energy storage device 33 forms an electrical energy storage device, specifically an accumulator. Other energy storage devices, such as batteries, are possible. The energy storage device 33 is arranged in a waterproof compartment of the monitoring device 30.

[0054] The energy storage 33 provides all electrical

[0055] Components of the manhole cover 10 are supplied with electrical energy. For this purpose, the energy storage device is installed in a fully charged state when needed, for example, before a race, and then removed again for recharging for the next use. This ensures a reliable power supply to all electrical components, especially system-relevant ones, during use, for example, during a race.

[0056] In addition, this allows regular and simple maintenance of the energy storage device 33 before each use, thereby reducing the risk of failure during use.

[0057] The monitoring device 30 is arranged in a protected housing 34 on the inside 12 of the manhole cover 10. For this purpose, the manhole cover

[0058] 10 has a housing receiving means 13, which is configured in a stub-like manner, protruding from the inner side 12 of the manhole cover 12 and arranged centrally to the manhole cover 10. The cylindrical housing 34 of the monitoring device 30 is arranged in the housing receiving means 13. The housing 34 forms a protected receiving space for the components of the monitoring device 30, enclosing the antenna 32, the electronics 34, and the energy storage device 33.

[0059] In order to lift the shaft cover 10 in the unlocked state from the shaft frame 40 and to place it on the shaft frame 40,

[0060] 11 of the manhole cover 10 two tool holders 14 for corresponding tools, for example hooks, are provided.

[0061] The screws 22 of the locking devices 20 each have a screw head that is arranged in a respective recess of the manhole cover 10 and is substantially flush with the outer side 11 of the manhole cover 10. The screw heads of the screws 22 are thus countersunk into the manhole cover 10, so that the outer side 11 is as flat as possible to prevent them from being driven over, for example by racing cars.

[0062] The manhole cover 10 has a substantially circular outer contour, which is delimited on the inner side 12 by a circumferential, substantially annular support surface 15 of the manhole cover 10. The manhole cover 10 rests with its support surface 15 on the support surface 41 of the manhole frame 40. The manhole frame 40 has a laterally circumferential frame wall 43. The frame wall 43 forms a nozzle, which is closed by the manhole cover 10 on a side facing away from the manhole. On a side facing the manhole, the frame wall 43 merges into a radially outwardly extending, annular frame base 44.

[0063] The shaft frame 40 has a projection 42. The projection 42 is formed circumferentially on the inside of the frame wall 43. The projection 42 thus extends radially inward from the frame wall 42, having a substantially circular geometry. On a side of the projection 42 facing away from the shaft, the support surface 41 is arranged, on which the shaft cover 10 rests. The latch 21 of the locking device

[0064] 20 engages behind the projection 42 of the shaft frame 40 in locking position II and in pressing position III, so that the projection 42 of the shaft frame 40 is arranged between the bolt 21 and the shaft cover 10.

[0065] In the pressing position III, the bolt 21 presses against the projection 42, so that the manhole cover 10 is pressed firmly against the support surface 41 of the manhole frame 40. The projection 42 is thus held by the bolt

[0066] 21 and the manhole cover 40 are pressed together. The contact force can be adjusted using screw 22.

[0067] Between the manhole cover 10 and the manhole frame 40, specifically the projection 42 of the manhole frame 40, a sealing means 45 is arranged, which extends circumferentially along the projection 42. The sealing means 45 can also be designed differently. A manhole cover 50 without a sealing means between the manhole cover 10 and the manhole frame 40 is also possible.

[0068] Fig. 2 shows a top view of the manhole cover 50 from Fig. 1. The essentially circular manhole cover 10 is arranged in the manhole frame 40, wherein the circular ring-shaped manhole base 44 surrounding the frame wall 43 is clearly visible in the top view. The three locking devices 20 evenly distributed around the circumference can be seen. The two tool holders 14 arranged opposite one another are also clearly visible. The following explains the operation of a monitoring system according to an exemplary embodiment of the invention for a race track, specifically the Formula 1 race track in Las Vegas. The monitoring system comprises several, specifically 14, previously described manhole covers 50 and a monitoring center. The monitoring center is designed to receive information about the position of the bolt 21 from the monitoring device 30 and to visualize the position of the bolt 21.

[0069] Fig. 3 shows such a visualization of the locking positions provided by the monitoring system. The three locking latches 21 of the manhole cover 50 can each be arranged in the unlocking position I, the locking position II, or the pressing position III. Thus, a total of 27 different combinations of the three locking positions I, II, and III are possible, seven of which are shown in Fig. 3 (indicated by seven pie charts).

[0070] Each combination of the three locking positions I, II, III forms a secured state of the manhole cover 50 or the manhole cover 10, wherein the manhole cover 50 is in an unlocked state I, a locked state II, or a pressed-in state III (indicated by three circles above the pie charts). The manhole cover 50 is in the unlocked state I when at least one of the three locking bolts 21 is in the unlocked position I. If none of the three locking bolts 21 is in the unlocked position I and at least one of the three locking bolts 21 is in the locked position II, the manhole cover 50 is in the locked state II. Only when all three locking bolts 21 are in the pressed-in position III is the manhole cover 50 in the pressed-in state III and thus secured. Otherwise, the manhole cover 50 is unsecured.

[0071] Fig. 4 shows a visualization of the securing states of the manhole covers 50 on the race track provided by the monitoring system. Since all manhole covers 50 are in the pressing state III, i.e., secured, the race track is open for use, for example, for a race (indicated by the status "OK"). In this case, all latches 21 are in the pressing position III. In Fig. 5, a detailed view of the locking device 20 of the manhole cover 50 from Fig. 1, the latch 21 is shown in the pressing position III. Since the latch 21 engages behind the projection 42 of the manhole frame 40 and is simultaneously pulled toward the manhole cover 10 by the screw 22, the latch 21 presses against the projection 42 of the manhole frame 40, so that the manhole cover 10 is pressed firmly against the support surface 41 of the manhole frame 40. The bolt 21 sits with its projection 23 in a cube-shaped recess on the manhole cover 10.

[0072] By pressing the latch 21 against the projection 42 of the shaft frame 40, the magnet 35 is held directly beneath the sensor. The distance between the magnet 35 and the sensor 31 is thus minimal, allowing it to be clearly assigned to the contact position III of the latch 21. By detecting this previously known, unique distance, the contact position III of the latch 21 is recognized.

[0073] By loosening the screw connection between screw 22 and latch 21, for example, due to vibrations when a racing car drives over the manhole cover 50 or due to actuation of the screw 22 using an appropriate tool, the latch 21 is moved from the contact position III to the locking position II. Since the latch 21 continues to sit with its projection 23 in the cube-shaped recess on the manhole cover 10, a pivoting movement of the latch 21 about the axis of the screw 22 is prevented.

[0074] Fig. 6 shows the latch 21 from Fig. 1 in locking position II. It can be clearly seen that in locking position II, the latch 21 continues to engage behind the projection 42 of the shaft frame 40, so that the shaft cover 10 continues to be locked to the shaft frame 40. However, in locking position II, the latch 21 does not press against the projection 42 of the shaft frame 40, but rests essentially loosely against the projection 42.

[0075] Due to the movement of the bolt 21 from the pressing position III to the locking position II (indicated by the downward-pointing arrow), the distance between the magnet 35 and the sensor 31 is increased compared to the pressing position III. Since this increased distance can also be clearly assigned to the locking position II of the bolt 21 due to the design, the detection of this distance makes it possible to identify the locking position II of the bolt 21.

[0076] If the bolt 21 is moved from the locking position II to the unlocking position I by further loosening the screw connection between screw 22 and bolt 21, the bolt 21 lifts off the projection 42 of the shaft frame 40. In doing so, the bolt 23 is moved far enough away from the shaft cover 10 that the projection of the bolt 23 is completely released from the cube-shaped recess on the shaft cover 10. Since the cube-shaped recess on the shaft cover 10 no longer counteracts a pivoting movement of the bolt 21, the bolt 21 is pivoted about the axis of the screw 22 until it abuts the stop for the bolt 21 in the unlocking position I.

[0077] The latch 21 in unlocking position I is shown in Fig. 7. Since the latch 21 no longer engages behind the projection 42 of the shaft frame 40, the locking device 30, i.e. the locking of the shaft cover 10 or the shaft cover 50, is unlocked.

[0078] The distance between magnet 35 and sensor 31 is further increased compared to locking position II due to the pivoting movement of the bolt 21 from locking position II to unlocking position I. Since, due to its design, the magnet 35 is only arranged at such a distance from the sensor 31 in unlocking position I, the unlocking position I of the bolt 21 can be detected by detecting this distance.

[0079] Fig. 8 shows the visualization from Fig. 4, with one manhole cover 50 in locking state II, i.e., unsecured. The remaining manhole covers 50 are equivalent to the visualization from Fig. 4 in pressing state III and thus secured.

[0080] Since, in comparison to Fig. 4, not all manhole covers 50 are in contact state III or secured, the race track is not released for use, for example, for a race (indicated by the status "Not OK"). In this way, the monitoring center informs the responsible service personnel, who can intervene immediately, for example, interrupt a race. For this purpose, the monitoring center can send out an alarm.

[0081] Since the unsecured manhole cover 50 is in locking position II, i.e., all three bolts 21 in locking position II engage behind the manhole frame 40, lifting of the manhole cover 10 from the manhole frame 40 is prevented. Informed service personnel can thus intervene before one of the three bolts 21 moves from the locking position III into the dangerous, unlocked area and allows the manhole cover 10 to be lifted.

[0082] Reference symbol:

[0083] 10 manhole covers

[0084] 11 Outside

[0085] 12 Inside

[0086] 13 Housing support

[0087] 14 tool holders

[0088] 15 Support surface of the manhole cover

[0089] 20 Locking device

[0090] 21 bars

[0091] 22 Screw

[0092] 23 projection of the bolt

[0093] 30 Monitoring device

[0094] 31 Sensor

[0095] 32 antenna

[0096] 33 energy storage

[0097] 34 housings

[0098] 35 Magnet

[0099] 36 Electronics

[0100] 40 shaft frames

[0101] 41 Support surface of the shaft frame

[0102] 42 Projection of the shaft frame

[0103] 43 frame wall

[0104] 44 frame floor

[0105] 45 Sealant

[0106] 50 Manhole cover I Unlocking position, unlocking state

[0107] II Locking position, locking state

[0108] III Contact position, contact state

Claims

CLAIMS Manhole cover (10) for a manhole cover (50) comprising - at least one locking device (20) for locking the manhole cover (10) to a manhole frame (40) of the manhole cover (50), wherein the locking device (20) has a bolt (21) which is movable between an unlocking position (I) and a locking position (II), and - a monitoring device (30) for monitoring the locking, characterized in that the bolt (21) is movable from the locking position (II) into a pressing position (III) in order to press the manhole cover (10) firmly against the manhole frame (40) during use, wherein the monitoring device (30) is designed to detect the unlocking position (I), the locking position (II), and the pressing position (III) of the bolt (21). Manhole cover (10) according to one of the preceding claims, characterized in that the locking device (20) has at least one screw (22) which can be actuated from an outer side (11) of the manhole cover (10), and which moves the bolt (21) between the locking position (II) and the pressing position (III) during use.Manhole cover (10) according to claim 2, characterized in that the screw (22) is adapted to move, in particular to pivot, the latch (21) between the unlocking position (I) and the locking position (II). Manhole cover (10) according to one of the preceding claims, characterized in that the locking device (20) has a stop, in particular. Angle stop for the bolt (21) in the unlocking position (I) and in the locking position (II). Manhole cover (10) according to one of the preceding claims, characterized in that the manhole cover (10) has at least two, preferably three, locking devices (20). Manhole cover (10) according to claim 5, characterized in that the locking devices (20) are distributed, in particular evenly distributed, in the circumferential direction of the manhole cover (10). Manhole cover (10) according to one of the preceding claims, characterized in that the monitoring device (30) has at least one sensor (31), in particular an inductive sensor (31), preferably a Hall sensor (31), for detecting the position of the bolt (21).Manhole cover (10) according to one of the preceding claims, characterized in that the monitoring device (30) has an antenna (32), in particular a ceramic antenna (32), in order to wirelessly transmit the information about the position of the bolt (21) to a monitoring center. Manhole cover (10) according to one of the preceding claims, characterized in that the monitoring device (30) has at least one energy storage device (33) for self-sufficient energy supply. Manhole cover (10) according to one of the preceding claims, characterized in that the monitoring device (30) is arranged in a protected housing (34) on an inner side (12) of the manhole cover (10). Manhole cover (50) with a manhole cover (10) according to one of the preceding claims and a manhole frame (40) for receiving it. of the manhole cover (10), wherein the manhole cover (10) rests on a support surface (41) of the manhole frame (40). Manhole cover (50) according to claim 11, characterized in that the bolt (21) of the locking device (20) engages behind the manhole frame (40), in particular a projection (42) of the manhole frame (40), in the locking position (II), and presses against the manhole frame (40), in particular the projection (42) of the manhole frame (40), in the pressing position (III), so that the manhole cover (10) is pressed firmly against the support surface (41) of the manhole frame (40). Monitoring system with at least one manhole cover (50) according to claim 11 or 12 and a monitoring center, wherein the monitoring center is designed to receive the information about the position of the bolt (21) from the monitoring device (30) and to visualize the position of the bolt (21).

Images