CH716396A2 - Closure cap for a hydrant. - Google Patents

Abstract

The closure cap (25) for a hydrant comprises a closing plate (27) with bolts (29) or other connecting elements for connecting the closing plate (27) to an outlet coupling of the hydrant. A hydrant device (2) is arranged on the outside of the closing plate (27), protected from the pressurized water of the hydrant. The hydrant device (2) comprises an electronic control which is arranged in a toroidal housing with a central opening through it.

Description

description

The invention relates to a closure cap for a hydrant according to the features of claim 1.

It is known to arrange electronic controls in hydrants, in particular monitoring devices that send a message via a radio module as soon as a detection device signals that the respective hydrant has been put into operation.

EP3293315A1 discloses a monitoring device which is arranged on a closing element or cover for closing a standardized outlet coupling of a hydrant. The monitoring device comprises a battery, a detection device for detecting activation of the hydrant and a signaling device with a mobile radio module. These elements are arranged within a pipe section which protrudes from the inside of the cover and is tightly closed by a cover element. The mobile radio module is connected to an antenna on the outside of the cover by means of an HF line. The detection device comprises a position sensor for detecting a rotation of the lid and a capacitive water sensor for detecting water that is in contact with the lid member within the hydrant. The pipe section and the cover element with the water sensor are arranged radially inside an annular sealing element which is used to seal the outlet coupling when the cover is closed. As soon as at least one of the sensors responds, the mobile radio module sends a corresponding message to a management device. A waiting time of a few minutes can then be provided in order to prevent multiple transmission of radio messages when the hydrant is started up. To save the battery, the device can also include a reed switch. The transmission of radio-based messages is only activated after the reed switch has been triggered without contact by a magnet during the initial installation.

When arranging an electronic device on a cap for an outlet coupling of a hydrant, various influencing factors must be taken into account, e.g. limited space, possible risk from pressurized water of the hydrant, service life of an autonomous energy supply, protection against damage, ensuring the functionality of the electronics.

Although the device known from EP3293315A1 partially discloses measures for saving energy, the energy supply of internal batteries is unnecessarily quickly exhausted. The batteries must be replaced accordingly frequently. This problem is particularly troublesome since the batteries are small due to the limited space and only have comparatively small capacities. The operating costs of such devices are correspondingly high.

It is therefore an object of the present invention to provide a closure cap for an outlet coupling of a hydrant with an electronic device protected from environmental influences.

This object is achieved by a closure cap for a hydrant according to the features of independent claim 1.

The closure cap comprises a toroidal housing which has a central opening and is arranged on the outside of a closing plate protected from pressurized water of the hydrant. Connecting elements for releasably attaching the closure cap to an outlet coupling of the hydrant are arranged on the closing plate. A polygonal bolt connected to the locking plate in a non-rotating manner protrudes into the central opening of the housing or through this opening so that it can be rotated together with the locking plate with a hydrant wrench or ring spanner to remove or attach the locking cap. The polygonal bolt preferably comprises a radially protruding round collar. This serves as a stop for attaching the housing to the striker. For this purpose, the housing comprises an annular shoulder adjacent to the central opening. This shoulder is generally recessed opposite the highest point of the housing at the lower end of a substantially cylindrical or slightly conical inner wall.

The housing preferably comprises an annular housing base and an annular domed housing hood, which can be connected to one another so that they together form a closed, sealed housing for receiving an electronic device or an electronic controller. The cross-sectional shape of the housing hood can be specified as desired. Preferably, the housing hood comprises an approximately cylindrical or slightly conical inner wall section and an outer wall section of the same type, which are connected to one another via a straight or curved bridge section, adjacent to the central opening. Relative to the size of the closure cap, this results in a comparatively large housing volume in which the electronic control can be arranged. The electronic control, which is also referred to as a hydrant device with or without a housing, comprises an energy storage device, in particular a battery, and is thus able to function autonomously. In preferred embodiments, all electronic parts of the hydrant device are arranged on an annular circuit board. Such hydrant devices can be produced comparatively inexpensively. The service life of the energy storage of such hydrant devices can be maximized through efficient energy management. This is explained in more detail using the example of a hydrant device that is used to monitor the commissioning of the respective hydrant.

The electronic control includes a microcontroller that puts itself in a power-saving sleep mode when it does not have to process any programs.

The electronic control further comprises a sensor arrangement with at least one activation sensor that wakes the microcontroller when the hydrant is started up. The activation sensor is arranged on a movable hydrant part in such a way that it generates a signal to wake up the microcontroller when the hydrant is started up.

After waking up from sleep mode, the microcontroller checks whether there is actually a start-up. Measured variables detected by the activation sensor and / or one or more additional sensors are compared with one or more stored comparison patterns. At least one of these comparison patterns corresponds to a characteristic pattern for values of one or more sensors, as they arise when the respective hydrant part is moved when the hydrant is put into operation.

If there is a sufficiently good match between the current measured variables detected by the sensors and this stored pattern, this is assessed as commissioning. The microcontroller then carries out the process steps intended for commissioning. The checking of sensor signals after the activation of the microcontroller enables a comparatively reliable detection of actual commissioning of the hydrant. As an option, typical comparison samples can also be saved for circumstances other than commissioning. This allows different processes to be carried out depending on the recorded measured variables, for example the recording and storage of measured variables.

When actual commissioning is recognized, a communication device sends corresponding data to a gateway in an energy-saving manner. From there, the data is forwarded to a network server for further processing. If the measured variables recorded by sensors do not correspond to a comparison pattern after activation of the microcontroller, for example if a hydrant is knocked over or damaged by a vehicle, the communication device can optionally send a corresponding message. Alternatively, comparison patterns could be stored with which the avoidance of a hydrant can be recorded. In such cases, the communication device could preferably send an alarm message with the highest priority without delay.

The invention is described in more detail below with the aid of a few figures. Show it

Figure 1 a monitoring system for hydrants,

Figure 2 is a schematic representation of a hydrant device,

Figure 3 is a view of a post hydrant

FIG. 4 shows an external view of a closure cap for an outlet coupling of the hydrant,

FIG. 5 shows an interior view of the closure cap from FIG. 3,

FIG. 6 shows a cross section of the closure cap from FIG. 3,

FIG. 7 shows an exploded view of the closure cap from FIG. 3.

Figure 1 shows a monitoring system for monitoring hydrants 1. Each hydrant 1 comprises a hydrant device 2 with a communication device 3 for unidirectional or bidirectional communication with gateways 5 of a radio network.

Each hydrant 1 is arranged within radio range of at least one gateway 5 of the radio network. The radio range denotes the maximum distance of a hydrant device 2 from the respective gateway 5 at which essentially interference-free communication between the hydrant device 2 and this gateway 5 is possible. The radio range depends on various factors such as transmission power and reception sensitivity, transmission frequency, bandwidth, free field attenuation, attenuation by obstacles, etc. In FIG. 1, the radio ranges of three gateways 5 are shown by dotted lines 7 by way of example. Hydrant devices 2 can communicate with the respective gateway 5 within these areas.

The radio network is a network in which data can be transmitted with low transmission power over comparatively large distances of, for example, several kilometers, in particular a Low Power Wide Area Network (LPWAN). Such networks are already widely available in many places. Networks based on standards of low-energy radio technology can be created and / or expanded comparatively easily and inexpensively. Monitoring systems can therefore also be set up in areas that are not comprehensively connected to a cellular network.

Examples of suitable networks are LoRaWan and SigFox. The corresponding technologies are assumed to be sufficiently known and are not explained in detail here. They only require low bandwidths and enable energy-efficient data transmission. This applies in particular when small data volumes have to be transmitted only with low frequency during short time intervals. Networks such as LoRaWAN can be set up easily and needs-based in frequency ranges of ISM bands that can be used without a license or approval. Depending on the geographic region, frequencies from 433.05 to 434.79 MHz can be used for this purpose

and from 863 to 870 MHz. Since electromagnetic radiation penetrates buildings well in these frequency ranges, radio ranges of 2 km or more can be achieved even in densely built-up urban areas. Larger areas can therefore be covered with just a few gateways.

The gateways 5 of the radio network are usually connected via the Internet 9 to a network server 11, which coordinates communication with the hydrant devices 2 via the gateways 5 and is connected to an application server 13. The application server 13 processes data that are transmitted from the hydrant devices 2. These data include an identification code that is unique for the respective hydrant device 2.

In addition, this data can also provide information on the time when the respective hydrant is put into operation

1, in particular a time and a date. The application server 13 stores the hydrant devices

2 transmitted information in a suitable manner, so that for each hydrant 1 there is at least one commissioning status, preferably in connection with a corresponding time information.

Instead of an absolute time, the hydrant device 2 can, for example, transmit the current value of a counter, which the hydrant device 2 increments periodically at intervals of, for example, 1 to 5 minutes. Such counters can be reset, for example, when the hydrant device 2 is started up for the first time, or after the sensor-based detection of a start-up of the hydrant 1 or when data is transmitted. The application server 13 includes stored information for processing such counter values, in particular for determining times when the respective hydrants 1 were put into operation.

Hydrant devices 2 can also be designed to transmit data to the application server 13 within a time interval of, for example, less than 5 minutes or immediately after the respective hydrant 1 has been activated. The time at which the data was transmitted can therefore be used as the time of commissioning. An explicit transmission of a commissioning time is not required in such embodiments. A tolerance of around 5 minutes for the time of commissioning is usually sufficient.

Different embodiments of hydrant devices 2 can, for example, be designed to transmit further data to the application server 13 via gateways 5 and network servers 11. Examples of such additional data are:

- Battery charge status, e.g. a status bit for falling below a limit value (minimum charge) or several bits for the ratio of remaining charge to maximum charge.

- Current and / or saved previous measured values of one or more sensors

- Values calculated from measured values from one or more sensors.

Hydrant devices 2 are preferably designed to send status reports periodically or in accordance with stored time specifications. Such status reports allow the network server 11 and / or the application server 13 to check the correct functioning of hydrant devices 2. If an expected message does not arrive, the application server 13 displays an alarm status for the respective hydrant device 2. This can be reset by an operator with the appropriate access rights after the problem has been rectified.

Alternatively or additionally, one or more of the sensors (21a, 21b) of the hydrant devices 2 can be designed to periodically record environmental parameters such as temperature, humidity, air pressure, brightness, wind speed, etc. according to the specifications of a program stored in the microcontroller 19 . These measured values or values calculated from them can be temporarily stored in a memory of the hydrant device 2, for example. Such data can, for example, be sent periodically or according to stored time specifications.

The application server 13 is designed to store and evaluate data received from hydrant devices 2, e.g. in the form of data records, and to provide corresponding information for display and / or further processing by clients. Such clients are, for example, computers 15 in a monitoring center and mobile terminals 17 such as tablets, notebooks or cell phones. The clients include client software or app for querying, filtering, sorting and displaying information, for example in the form of lists and / or area maps with the locations of hydrants 1. The data is preferably provided by means of a web application.

Figure 2 shows schematically parts of a hydrant device 2. These include

- an energy storage device 4 which can e.g. comprise one or more batteries,

- the communication device 3 with a radio transmitter 3a and optionally with a radio receiver 3b,

- an electronic control with a microcontroller 19,

A sensor arrangement 21 which comprises at least one activation sensor 21a, the state of which can be changed by the movement of a movable hydrant part when the hydrant 1 is put into operation.

FIG. 3 shows a view of a post hydrant or, for short, a hydrant 1. Parts that are moved when the hydrant 1 is started up are, for example, a cover 23 which covers the operating elements of the hydrant 1, actuating spindles for actuating the valves (not shown) or sealing caps 25 for generally standardized outlet couplings.

The activation sensor 21a can in particular be an acceleration sensor or an inclination sensor which is arranged on such a movable part of the hydrant 1. When this part is moved to put the hydrant 1 into operation, for example a voltage or an electrical resistance of at least one output of the activation sensor 21a changes. This change can take place in stages or continuously, depending on the embodiment of the activation sensor 21a. In particular, the output of the activation sensor 21a can be digital. The measured variable detected by the sensor 21a is compared with a predeterminable reference value. If the measured variable is smaller than the reference value, the output has a first logical state, e.g. "0". If the measured variable is greater than or equal to the reference value, the output has a second logical state, e.g. "1".

Passive switches with electrical contacts can also be used as activation sensors 21a, the contacts being connected to one another or separated from one another when the respective part is moved, e.g. by changing a mechanical force or a magnetic force (e.g. in the case of a reed switch). As a rule, with such switches, one of the contacts is connected to the potential of the operating voltage of the hydrant device 2, the other contact to an interrupt input of the microcontroller 19. The microcontroller 19 can be put into an energy-saving sleep mode in which essentially only the state of the interrupt input is monitored. A control program of the microcontroller 19 is preferably designed to interrupt the energy supply to parts of the hydrant device 2 that are not required during the duration of the sleep mode before switching to sleep mode. Such parts are, for example, the communication device 3 or the radio transmitter 3a and / or the radio receiver 3b as well as further sensors 21a, 21b of the sensor arrangement 21, which are not intended to "wake" the microcontroller 19 from sleep mode.

The microcontroller 19 can be "woken up" from the sleep mode by the following events or alarm signals in order to continue executing a control program in a normal operating mode:

- Wake-up signal at the interrupt input

- Reaching a specified time or expiry of a timer.

In the normal operating mode, the microcontroller 19 can execute any predetermined processes or programs that go beyond the mere monitoring of an interrupt input. With such processes, for example, signals at further inputs of the microcontroller 19 can be monitored and / or data can be stored, processed, sent and received. In the normal operating mode, the microcontroller 19 can preferably also control the energy supply of parts of the hydrant device 2 such as the radio transmitter 3a, the radio receiver 3b or one or more sensors 21a, 21b of the sensor arrangement 21. The switching on and off of such parts by means of electronic switching elements according to the respective requirement contributes to the minimization of the energy consumption of the hydrant device 2.

The microcontroller 19 comprises a stored test program which determines the respective cause of this alarm triggering after each alarm triggering or after each waking up from sleep mode and then initiates the execution of further procedural steps that are specified for this cause. If parts that have been switched off are required to carry out these process steps, the power supply is switched on again for these parts, at least temporarily.

The cause of the alarm triggering can be a signal at the interrupt input or the expiry of an internal timer.

If the alarm has not been triggered by an internal timer, the microcontroller 19 checks in embodiments with a plurality of activation sensors 21a, which activation sensor 21a triggered the alarm. The microcontroller 19 can detect the state of at least one sensor 21a, 21b of the sensor arrangement 21 and / or changes in this state within a predetermined time interval. The value of a measured variable provided on the output side is referred to as the state of a sensor 21a, 21b. Such measured values can be recorded at one or more analog and / or digital inputs of the microcontroller 19. The interrupt input also belongs to these inputs. As an alternative, measured values from several sensors 21a, 21b can also be recorded at an input of the microcontroller 19 in a time-staggered manner using the multiplex method. One or more sensors 21a, 21b can also be integrated in the microcontroller 19. Analogously, inputs and connections from sensors 21 a, 21 b to such inputs can then also be integrated in the microcontroller 19. The space requirement of the hydrant device 2 can be reduced by a higher degree of integration. As a rule, this also reduces energy consumption.

The hydrant device 2 can, for example, comprise an acceleration sensor, which is arranged in particular in a closure cap 25 of an output coupling of the hydrant 1 and can be designed to detect accelerations in one or, alternatively, several directions. This acceleration sensor is an activation sensor 21a which activates the microcontroller 19 as soon as the acceleration in at least one of the directions exceeds a predetermined reference value.

The electronic control includes stored data on which sensors 21a, 21b can be used to determine that the hydrant 1 is in operation, and how, on the basis of measured values of these sensors 21a,

21b commissioning of the hydrant 1 can be recognized. This information can be stored in the microcontroller 19 in particular in the form of program code and / or stored data.

If only the acceleration sensor can be used to assess commissioning, for example one or more of the following criteria can be specified for recognizing commissioning:

The measured acceleration in one or more directions exceeds a stored reference value, which can preferably be set independently of the reference value for activating the microcontroller 19.

- During a measurement interval, which lasts, for example, in the order of magnitude of 1s to 10s, the measured acceleration exceeds the specified reference value several times or at least two or three times.

The accelerations measured for different directions exceed the specified reference value in a specific sequence. The same or different reference values can be specified for different directions.

The movement of hydrant parts when the hydrant 1 is put into operation causes typical patterns, in particular in the measured values of activation sensors 21a. Such patterns can generally be described for one or more of the sensors 21a, 21b by time sequences of measured values or as functions. This includes functions with values that are constant over time. Subsets of such patterns, such as one or more specific constellations of measured values from a plurality of sensors 21 a, 21 b at one or more times or during one or more time intervals, are also patterns. In addition to or instead of current measured values, values derived from such measured values such as mean values formed during specified time intervals, integrated values or filtered values can also be compared with corresponding stored patterns.

The conditions that must be met for the detection of the commissioning of a hydrant 1 are generally defined independently of the conditions for activating the microcontroller 19.

Such conditions can be stored in a memory of the electronic control, in particular of the microcontroller 19, in particular as a comparison pattern for comparing measured values of one or more sensors 21 a, 21 b. For each sensor 21a, 21b to be taken into account, comparison samples comprise at least one comparison value, preferably a number of comparison values, which the respective measured variable is supposed to assume in a specific time sequence.

To determine whether the hydrant 1 is in operation, a test program of the microcontroller 19 records the measured values of one or more sensors 21a, 21b at one or more times and after the activation or change from sleep mode to normal operating mode evaluates this. These measured values or values derived therefrom such as mean values or integrated values during certain time intervals are compared with corresponding comparison values from comparison samples. If the recorded values correspond to the comparison values of the comparison sample within predeterminable tolerance limits of, for example, less than +/- 10% or +/- 20%, this means that the hydrant 1 is put into operation, and the microcontroller 19 executes method steps assigned to the respective comparison sample.

To illustrate this, an example: a sensor arrangement 21 can include, for example, an acceleration sensor and two differently oriented inclination sensors on a closure cap 25. A signal from the acceleration sensor wakes the microcontroller 19. A test program is then started.

This monitors the states of the inclination sensors during a specified test duration, which can be, for example, in the order of magnitude of 1s to 10s. If, during this test period, the measured variable of the first inclination sensor first exceeds or falls below a first comparison value and then the measured variable of the second inclination sensor exceeds or falls below a second comparison value, this is assessed as putting hydrant 1 into operation.

[0046] Alternatively, the one or more detection of a change in the inclination position by one or more inclination sensors could also be evaluated as commissioning.

The comparison values for changes in the inclination position can, for example, be defined relative to a reference position which corresponds to the closed position of the closure cap 25. Alternatively, comparison values for one or more inclination sensors for an open position of the closure cap 25 could be specified, the closure cap 25 hanging on a flexible securing element 42.

As an alternative or in addition to inclination sensors, start-up of the hydrant 1 can also be determined by monitoring the signals from the acceleration sensor. In particular, a typical course of the measured variable of the acceleration sensor when opening the cap 25 can be stored as a model function, e.g. as a sequence of comparison values. Positive and negative values correspond to accelerations in opposite directions.

Preferably, comparison or reference values can be specified or changed, for example when installing a hydrant device 2 or at a later point in time. For example, reference values for inclination sensors can be determined and stored on the basis of measured values from these inclination sensors when they are first installed in a specific hydrant 1. This has the advantage that the stored values are optimally adapted to the respective arrangement

of the hydrant 1 and the hydrant device 2 are adapted. The hydrant device 2 includes an initialization mode for this purpose. The change to the initialization mode can be initiated, for example, by a reset switch on the hydrant device2.

On the basis of stored comparison or reference patterns, such as those caused when a cap 25 is opened, actual commissioning of the hydrant 1 can be distinguished from other events such as tremors caused by earthquakes or manipulations in which a cap 25 moves, however does not open fully. This enables a more precise identification of the actual commissioning of the hydrant 1.

Due to the reliable detection of actual start-up of a hydrant 1, in particular the sending of unnecessary or incorrect messages after activation of the microcontroller 19 can be prevented. This improves the quality of the transmitted data and prevents unnecessary energy consumption.

[0052] Optionally, the electronic control can include stored comparison patterns for several different events. For example, the sensor arrangement 21 can comprise a reed switch as an activation sensor 21a. Before carrying out maintenance work, a person can change the state of this reed switch without contact using an external magnet. During the subsequent check, the microcontroller 19 recognizes the closing or opening of the reed contact as the cause of the activation. This can optionally be confirmed by an acoustic or optical signal generator. The hydrant device 2 now has a maintenance status for a maximum duration of, for example, 20 minutes or until the reed switch is next actuated, in which the sending of messages relating to commissioning is prevented. As a result, the cap 25, for example, can be opened in order to carry out maintenance work.

As an alternative or in addition to the acceleration sensor, an inclination sensor, for example, can be used as an activation sensor 21a to wake up the microcontroller 19 and / or to determine that the hydrant 1 is in operation. The inclination sensor is designed to detect at least one position angle of the hydrant device 2 relative to the direction of the earth's gravitational force. Inclination sensors can in particular include force or acceleration sensors which detect components of the earth's gravitational force on a mass body in two or three orthogonal directions.

The microcontroller 19 can also be woken up from the sleep mode by an internal timer in order to carry out predetermined actions. Such an action is, for example, the storage and / or further processing of one or more measured values from sensors 21 a, 21 b. The microcontroller 19 optionally carries out the associated process steps.

If at least one method step is the sending of a message, a maximum delay time until the message is sent can be defined for this according to the urgency of such a message. The maximum delay time can be any value between zero and several weeks, such as one or more hours, days, or weeks. This ensures that urgent messages are transmitted with as little delay as possible. Data that are not time-critical can, for example, be transmitted together with other data at a later point in time. In this way, in particular, unnecessarily frequent switching on and off of the radio transmitter 3b can be avoided. Energy stored in the energy store 4 is used efficiently in this way.

To transmit data, the microcontroller 19 activates the radio transmitter 3a and sends a message with the corresponding data. Such messages each include the unique identification code of the respective hydrant device 2. Status information is preferably also sent, which indicates what type of data is being transmitted. One type of message are status messages that indicate to the application server 13 that the respective hydrant device 2 is functioning correctly and / or the state of charge of the energy store 4 and / or a time indication that indicates when the next status message is expected to be sent.

If hydrant devices 2 comprise a communication device 3 with an additional receiver 3b for bidirectional communication with gateways 5, the reception of messages can be limited to certain time windows. Outside this time window, receivers 3b can be switched off so that the energy consumption of receivers 3b is minimal. Such reception time windows are preferably provided immediately afterwards or with a defined time delay after the sending of data by the respective hydrant device 2. Several receive time windows can also be defined between two successive transmission cycles.

The communication server 11 transmits data, which are intended for individual, several or all hydrant devices 2, to the corresponding gateways 5. There these data are stored in intermediate stores. After a message has been transmitted from a hydrant device 2 to a gateway 5, the gateway 5 transmits the associated, temporarily stored data to the respective hydrant device 2 in one or more time windows provided for this purpose.

The possibility of transmitting data to a hydrant device 2 (upload) can be used, for example, for one or more of the following purposes:

Transmission of program code (firmware) and / or data for the configuration of the hydrant devices 2. Below are some examples of such data:

- synchronization times for timers and clocks,

- Specified times or time intervals for the acquisition of measurement data by one or more of the sensors 21a, 21b,

- default times for sending data to the gateways 5,

- Reference values or comparison values, in particular for measured values of one or more sensors 21a, 21b, etc.

Figures 4 and 5 show the outside and the inside of an exemplary closure cap 25, which is suitable for closing standardized Storz outlet couplings of hydrants 1 and comprises a hydrant device 2. Figure 6 shows a cross section of this closure cap 25 and Figure 7 shows an exploded view , the parts of the closure cap 25 being distributed along a cover axis A.

The closure cap 25 comprises a closure plate 27 with bolts 29 of a Storz bayonet lock. In alternative embodiments, the closing plate 27 could also comprise other connecting elements such as internal or external threads (not shown). The closing plate 27 is preferably made from an aluminum alloy such as AlMgSil. A square recess 31 arranged centrally at the cover axis A enables a bolt 33 to be inserted in a manner that is secure against rotation and which comprises an end region with a matching square section. The bolt 33 comprises a preferably continuous axial bore 34 with an internal thread 35. The bolt 33 and recess 31 could alternatively also have other 3-edged or polygonal profiles. Between the end regions, the bolt 33 comprises a radially protruding round collar 37. This collar 37 serves as a stop for attaching a toroidal housing to the closing plate 27. The housing comprises an annular housing base 41 and a curved annular housing hood 43, which is preferably in combination with an inner one Ring seal 45 and an outer ring seal 47 can be connected to one another in a watertight manner. The connection can be made, for example, by means of three screws 49a, which are inserted into bores on the housing base 41 and screwed tightly to corresponding holding elements with internal threads on the inside of the housing cover 43. The bores preferably have an enlarged inside diameter on the input side for receiving the screw heads. This makes it easier to fasten the housing to the closing plate 27. The spaces between the bores and the screws 49 a are preferably sealed with sealing rings 46. The housing hood 43 comprises a recessed annular shoulder 44 adjacent to an inner opening at the cover axis A. The housing and the closing plate 27 are connected to one another by, when screwing a screw 49b into the internal thread 35 of the bolt 33, between a screw-side washer 51 and the collar 37 of the bolt 33 are held in a defined axial position. The screw 49b can have a continuous axial bore 48 (FIG. 6). The closure cap 25 thus also has a continuous recess which connects the inside and the outside with one another when the screw 49b is screwed into the bolt 33. If water is under pressure on the inside of the closure cap 25, it splashes out through the recess. This is a sign that a valve in the supply line to the outlet coupling of hydrant 1 is not correctly closed. The housing itself is shielded from areas of the hydrant 1 in which water can be under pressure. The interior of the housing is therefore well protected from the ingress of water. Between the annular disk 51 and the inside of the closing plate 27, a sliding ring 53 is mounted in an annular groove of the closing plate 27 and, adjacent to it, a plastic disk 55 with a central bore 57 with little play is mounted on a cylindrical end section 36 of the bolt 33. The inner diameter of the central bore 57 corresponds essentially to the outer diameter of the cylindrical end section 36 of the bolt 33. The end face of this cylindrical end section 36 is preferably arranged flush with the surface of the plastic disk 55 adjoining the central bore 57 or protrudes axially slightly beyond it by an overhang of, for example, less than 0.2 mm. The unit of bolt 33, closing plate 27, washer 51 and screw 49b can be rotated relative to the plastic disk 55 and relative to the housing. In the direction of the cover axis A, however, these parts have almost no freedom of movement.

A flexible securing element 42 such as a rope or a chain is preferably connected to the closure cap 25 in the area of the outer edge of the housing hood 43. If a closure cap 25 is arranged on an outlet coupling of a hydrant 1, one end of this securing element 42 is fastened in a captive manner, e.g. to an eyelet 40 of the hydrant 1.

When a closure cap 25 arranged on the outlet coupling of a hydrant 1 is opened, the connection between the closing plate 27 and the outlet coupling is released by turning the bolt 33 and the closing plate 27 connected to it. Due to frictional forces, the housing can also be rotated as far as the freedom of movement of the respective securing element 42 allows. The length of the securing element 42 limits the pivoting range in which the housing can be rotated about the cover axis A. As soon as the closure cap 25 is separated from the outlet coupling, it remains captively secured on the hydrant 1 by the securing element 42. After using the hydrant 1, the closure cap 25 is reconnected to the outlet coupling.

In addition to the electronic elements, the housing can also be a component of the hydrant device 2. The housing with the built-in electronics or the hydrant device 2 can be prefabricated as a unit. Conventional sealing caps 25 can easily be replaced by sealing caps 25 with hydrant devices 2.

Claims (12)

The electronic elements of the hydrant device 2 are arranged inside the housing, for example on a preferably ring-shaped circuit board 20 with bores for the screws 49a. At least one antenna of the communication device 3 can also be arranged inside the housing, for example on the circuit board 20. This is possible because at least the housing cover 43 is made from a plastic that can easily be penetrated by electromagnetic radiation, e.g. from impact-resistant polyamide. Furthermore, the electronics can include, for example, an acoustic and / or an optical signal transmitter, in particular a piezoelectric transducer and / or a light-emitting diode. These can be used, for example, to confirm or signal certain operating states during maintenance work or other manipulations on hydrant 1. The housing hood 43 can comprise a light-permeable section or can be made of a light-permeable material so that light from optical signal transmitters on the circuit board 20 is visible from the outside. In such embodiments with transparent housing hoods 43, photovoltaic cells can optionally also be arranged in the housing. These convert ambient light into electrical energy for storage in the energy store 4. The electronics of a hydrant device 2 arranged on a protective cap 25 can be designed in any other way and additionally or alternatively for other purposes than monitoring the start-up of the hydrant 1, for example as Data logger for storing environmental parameters such as temperature, air pressure, humidity, sound level, etc. Such parameters can be recorded periodically, for example. In addition or as an alternative to radio transmission to a gateway, such data could also be queried from a mobile device, for example via near-field communication. Claims 1. Closure cap (25) for a hydrant (1), comprising a closing plate (27) with bolts (29) or other connecting elements for connecting the closing plate (27) to an outlet coupling of the hydrant (1), an inside of the closing plate (27 ) facing the outlet coupling, characterized in that a hydrant device (2) is arranged on an outside opposite the inside of the closing plate (27), and that this hydrant device (2) comprises an electronic control which is in a toroidal housing with a continuous central Opening is arranged. 2. Closure cap (25) according to claim 1, characterized in that the housing comprises an annular housing base (41) and a curved annular housing hood (43) which can be connected to one another in a watertight manner. 3. Closure cap (25) according to claim 2, characterized in that the housing hood (43) comprises an annular shoulder (44) recessed opposite the highest point of the housing hood (43) adjacent to the central opening. 4. Closure cap (25) according to one of claims 1 to 3, characterized in that the closing plate (27) comprises a central polygonal recess (31), and that a matching polygonal end region of a bolt (33) through the central opening of the housing hood ( 43) is inserted through into the recess (31) of the closing plate (27) and connected to the closing plate (27) in a rotationally secure manner. 5. Closure cap (25) according to one of claims 3 to 4, characterized in that the bolt (33) has a radially protruding collar (37) as a stop for the annular shoulder (44) of the housing hood (43) and an axial bore (34 ) with an internal thread (35), and that the housing and the closing plate (27) are connected to one another by a screw (49b) screwed into the internal thread (35) between an annular disk (51) and the collar (37). 6. Closure cap (25) according to claim 5, characterized in that the screw (49b) has an axial bore (48). 7. Closure cap (25) according to one of claims 1 to 6, characterized in that the electronic control comprises the following: a) an energy store (4), b) a microcontroller (19) which can be operated in a sleep mode with minimal energy consumption and can be switched to a normal operating mode by a signal at an interrupt input, c) a sensor arrangement (21) with at least one activation sensor (21a), the state of which can be changed by the movement of a hydrant part when the hydrant (1) is put into operation, and d) a communication device (3), wherein the activation sensor (21a) is connected to the interrupt input of the microcontroller (19) so that the microcontroller (19) can be switched from the sleep mode to the normal operating mode by a signal from the activation sensor (21a), and that the electronic control is at least one stored Comprises comparison pattern for comparing measured values of the activation sensor (21a) and / or further sensors (21a, 21b) of the sensor arrangement (21) for the purpose of recognizing an activation of the hydrant 1. 8. Closure cap (25) according to claim 7, characterized in that the comparison pattern for comparing measured values of the activation sensor (21a) and / or the further sensors (21a, 21b) each comprises at least one comparison value. 9. Closure cap (25) according to claim 7 or 8, characterized in that the activation sensor (21a) is an acceleration sensor or an inclination sensor or a switch with an electrical contact. 10. Closure cap (25) according to one of claims 7 to 9, characterized in that the electronic control comprises one or more electronic switching elements controllable by the microcontroller (19) for switching on and off the power supply to parts of the electronic control that are only needed temporarily become. 11. Closure cap (25) according to one of claims 7 to 10, characterized in that the communication device (3) comprises a radio transmitter (3a) or a radio transmitter (3a) and a radio receiver (3b) which are used for unidirectional or bidirectional communication with gateways (5) a low power radio network (LPWAN) are formed. 12. Closure cap (25) according to one of claims 7 to 11, characterized in that the electronic control is arranged on an annular plate (20).