DE20018634U1 - Device for determining the operating time of devices which vibrate in their operating state, such as rented machines and units - Google Patents

Description

STUG05T6.doc

Device for determining the operating time of equipment that vibrates in its operating state, such as rented machines and units

The invention relates to a device for determining the operating time of devices vibrating in their operating state, such as rented machines and units, comprising the following device parts:

a sensor module that emits electrical signals, - at least one battery,

- a flip-flop which is controlled by the sensor module and, in conjunction with a counting pulse generator, provides a time count and a corresponding time display with a display.

In measurement technology, various devices known as operating hour counters with an internal power supply are known, which accumulate the operating time of devices or systems when they are supplied with voltage, for example. The control is carried out via a switching contact. Such operating hour counters are provided with a reset button, which is usually located on the front of the housing. The internal power supply is provided by means of a built-in battery. The disadvantage of the known

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The advantage of this device is that the accumulated time can be reset. In addition, it is hardly suitable for rental machines because manipulation of the device cannot be ruled out.

The object of the invention is to provide an autonomous device that is tamper-proof.

This problem is solved by features of the main claim.

In this case, the adjective "autonomous" refers to a device that does not require an external power connection. The device has an energy storage device in the form of a battery, preferably a lithium battery, and possibly also a built-in solar cell.

An important part of the device is a non-resettable activation circuit, which enables the device to be put into operation.

The sensor module can be equipped with a vibration sensor, preferably with a ball. The sensor module can also contain a Hall sensor.

The activation circuit comprises a storage element in the form of a bistable flip-flop and a start-up pulse generator, which ensures that the flip-flop is set to the initial value "Off*" when the battery is installed. The activation circuit also contains a magnetic sensor switch that can only be operated once without contact. In this state (initial value "Off*) the device initially remains out of operation until the activation circuit is switched to a state with the help of a magnet brought in from the outside via the magnetic sensor switch.

The "On" state is now maintained for the remainder of the battery's or toggle switch's lifespan, as there is no reset option.

The sensor module that emits the electrical signals controls a monostable flip-flop whose output remains in the "On" state for a certain period of time after a reset pulse from the sensor module and then automatically returns to the "Off" state. This period of time is approximately half of the smallest counting unit, for example half of a tenth of an hour. In the "On" state, the subsequent time counter continues the counting process.

This ensures continuous counting for at least the specified time period, even if the sensor module does not register any movement for a short time. By selecting an appropriate time period, approximately half of the smallest counter unit, the time count is correct as long as the average duty cycle is greater than the smallest counter unit.

The time counter module includes a counting pulse generator, a counter and a display, for example a liquid crystal display. The counting pulse generator and the display are supplied with operating voltage from the output of the monostable flip-flop of the sensor module, so they are only activated when the flip-flop is in the "On" state.

In the "Off" state, the generation of counting pulses and thus the time counting is prevented. However, the operating voltage is retained so that the current counter reading can be saved.

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The device can be attached to any suitable location on the machine. It is also possible to attach it in the area of a shaft coupling or working shaft in order to be able to register the rotations. Miniaturized electronic components such as Hall sensors are particularly suitable for this purpose.

Further features and advantages of the invention can be seen in the following embodiment, which is explained in more detail with reference to the drawing. The figures of the drawing show in detail:

Fig.l a housing with display, seen in perspective,

Fig.2 a circuit diagram,

Fig. 3 the interior of the housing with visible device parts,

and

Fig.4 Arrangement of a Hall sensor on a working device.

Figure 1 shows a device 100, the elements of which are housed in a rectangular, robust plastic housing 10. A display 6 is arranged on a front side 27 of the housing 10 in such a way that it is secured against unauthorized removal.

Figure 2 shows a schematic circuit diagram 30 which consists of the following main parts: an activation circuit 7, a sensor module 2 and a time counter module 3.

The activation circuit 7 comprises a lithium battery 4, a start-up pulse generator 11, a magnetic sensor switch 12 and a flip-flop 9, the output 18 of which is connected to the sensor module 2. The start-up pulse generator 11 is connected to a reset input 19 and, accordingly, the magnetic sensor switch 12 is connected to a set input 29 of the bistable flip-flop 9.

The sensor module 2 consists of a vibration sensor 22 and a monostable multivibrator 8. In the present case, the vibration sensor 22 contains a vibration ball 23 shown schematically in Figure 3. The vibration sensor 22 is connected to a reset input 24 of the monostable multivibrator 8. An output 25 of the monostable multivibrator is in turn connected to the time counter module 3.

The time counter module 3 consists of a counting pulse generator 13, a counter 16 and the digital display 6.

All of the above-mentioned components are first placed in the rectangular housing 10 and partially inserted into a circuit board 28 (see Fig. 3). The housing 10 is then welded.

Function:

The time counting process of the device 100 is initiated by moving or vibrating the counter. The counter counts as long as it is kept moving. A single movement pulse causes the counter to count for a period of 3 minutes. This period is extended by a further 3 minutes with each new movement pulse.

After every 6 minutes, i.e. one tenth of an hour, the meter stores the current counter reading in a non-volatile memory.

In idle mode, the display switches off to save power. When activated again by a movement impulse, the time count continues from the last saved counter value. The smallest counting unit is therefore 6 minutes.

The device is handed over to the customer in a deactivated state. In this state, no time is counted. The vibration sensor and the counter are switched off. The power consumption of the circuit is then approximately 1/10 of the self-charging current of the battery and can therefore be ignored. A storage time of 10 years is specified for the battery.

The device can be activated using the small bar magnet supplied, ie it can be switched on to start counting time. To do this, the bar magnet must be brought close to the sensor field marked 31. The counting process will then start immediately and last for 3 minutes. The counting process can be observed on the display with a starting value of 000,000 hours.

If the counter is in a motionless state, the display goes out after 3 minutes. The counting state is always indicated by the display being switched on.

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The device is removably attached to any location on the respective machine using a bracket (not shown), whereby care must be taken to ensure that the bracket is appropriately secured, for example with a lead or a seal that may only be broken by the lender.

The counter reading is displayed in hours. The decimal places are 1/10, 1/100 and 1/1000 of an hour. The counting range is from 000,000 hours to 99999.9 hours, corresponding to approximately 10 years. The display is only switched on in counting mode.

Fig. 4 shows a working device 33 with a rotary shaft 34 coupled to a tractor. A Hall sensor 32 arranged in a fixed position above the rotary shaft 34 is used to record the effective working time of the working device 33. A corresponding counterpart, namely a permanent magnet 35, is attached to the rotary shaft 34.

STUG 05 List of reference symbols

100 Device

2 Sensor module 3 Time counter module 4 battery 6 Display 7 Activation circuit 8th Toggle switch 9 Toggle switch 10 Housing 11 Commissioning pulse generator 12 Magnetic sensor switch 13 Counting pulse generator 16 counter 17 Solar cell 18 Exit 19 Reset input 21 Bullet 22 Vibration sensor 23 Vibration ball 24 Reset input 25 Exit 27 Front 28 Circuit board 29 Set input 30 circuit diagram 31 Sensor field 32 Hall sensor 33 Work equipment 34 Rotary shaft 35 Permanent magnet ti! .*····
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Claims (18)

1. Device (100) for determining the operating time of devices vibrating in their operating state, such as rented machines or units, comprising the following device parts: - a sensor module (2) emitting electrical signals, - at least one battery (4), - a monostable flip-flop (8) which is controlled by the sensor module (2) and, in conjunction with a counting pulse generator (13), supplies a time count and a corresponding time display with display (6), - a non-resettable activation circuit (7) with which the device can be put into operation, - and a waterproof housing (10) provided with the display (6), in which the sensor module (2), the time counter module (3), the battery (4) and the activation circuit (7) are housed, and which can be removably attached to the structure of the respective machine via a bracket. 2. Device according to claim 1, characterized in that the sensor module (2) contains a vibration sensor (22). 3. Device according to claim 1, characterized in that the sensor module (2) contains a Hall sensor (32). 4. Device according to claim 2, characterized in that the vibration sensor (2) is equipped with a ball (21). 5. Device according to claim 1, characterized in that the activation circuit includes a magnetic sensor switch (12) which can be actuated only once without contact. 6. Device according to claim 5, characterized in that the activation circuit (7) comprises a storage element in the form of a bistable flip-flop (9) and a start-up pulse generator (11). 7. Device according to claim 1, characterized in that the time counter module (3) comprises the counting pulse generator (13), a counter (16) and the display (6). 8. Device according to one of claims 1 to 7, characterized in that in the idle state of the device the display of the measured value can be switched off via a time delay element. 9. Device according to one of claims 1 to 8, characterized in that each pulse reported by the vibration sensor (2) activates the counting pulse generator (13) and the display (6). 10. Device according to one of claims 1 to 9, characterized in that the first display value after a pulse corresponds to a time stored in the counter (16). 11. Device according to one of the preceding claims, characterized in that the display value increases continuously starting from a certain time after activation of the counting pulse generator (13) by the pulse. 12. Device according to one of the preceding claims, characterized in that the time stored in the counter (16) increases step by step by time intervals. 13. Device according to one of the preceding claims, characterized in that after each pulse reported by the vibration sensor (2), the counting pulse generator (13) is activated for a holding time without new pulses reported by the vibration sensor (2). 14. Device according to one of the preceding claims, characterized in that the time stored in the counter (16) is increased by a time interval when the sum of the time between the pulses and the holding time is equal to the time interval. 15. Device according to one of the preceding claims, characterized in that the holding time is approximately half as long as the time interval. 16. Device according to one of the preceding claims, characterized in that it is equipped with at least one solar module (17) as a power supply. 17. Device according to one of the preceding claims, characterized in that the display (6) is backlit. 18. Device according to one of the preceding claims, characterized in that the sensor module having the Hall sensor (32) is arranged in the region of a coupling or rotary shaft (34) of the respective working machine.