JPS5820178B2 - Time division multiplex data transmission device with bus system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a bus system including a bus line and a plurality of subscribers connected to the bus line, and these subscribers transmit data to each other in a predetermined order and in a predetermined combination. each subscriber has at least one programmable counter, the counting input of which is connected to the clock generator, and the output of this counter being connected to the clock generator. are connected to a switching device for establishing a data transmission connection between the bus line and the data sending or receiving terminal of this subscriber, the counters of all subscribers being synchronized with each other, The present invention relates to a time division multiplex data transmission device having a bus system.

In known serial bus systems, data can be transmitted in a predetermined order between each predetermined subscriber on bus lines, which can include data lines and energy lines.

Even if all subscribers connected to the bus line are always ready, only one subscriber or a predetermined group of subscribers has to receive the data sent in each case for subsequent processing.

In order to select this subscriber or a predetermined group of subscribers, according to the prior art, address signals are sent out, which address signals allow this subscriber to be selected only to another desired subscriber or to another desired group of subscribers. Information is transmitted for further processing within the system.

The end of this transmission is indicated by a termination signal on the bus line, by which the next subscriber or next group of subscribers transmits information including a preceding address signal and a subsequent termination signal.

Such known devices for serial or time division multiplexed data transmission can be configured to transmit analog signals and/or so-called discrete signals containing only yes/no information.

In such a bus system, in order to improve the relative period used by the bus system for the transmission of originally effective information with respect to the entire transmission period including the transmission of address signals and termination signals, a patent application filed in 1983 was proposed. According to the specification of No. 139462, the following has already been proposed.

That is, each subscriber has at least one programmable counter which generates a control signal at the programmed count value and which counter has the same predetermined value for all counters. The counting input terminal of the counter is connected to the clock generator, and the first control output terminal of the counter is connected to the bus line and the data transmission terminal of this subscriber. or to a switching device for establishing a data transmission connection with a data receiving terminal, and the counters of all subscribers are synchronized with each other.

Furthermore, according to the said specification, when a short circuit occurs at one or more transmitting outputs of a subscriber, a sufficient signal change occurs on the bus line, which signal change is transmitted by the subscriber acting as a receiver. Measures have also been taken to enable evaluation.

For this purpose, the transmission output stages of the subscribers are each connected to the bus line via a resistor.

However, according to this proposal, the bus system is protected against destruction only in the case of special short circuits, ie short circuits in the transmission output stage.

The object of the invention is to provide a time-division multiplex data transmission device with a bus system which is protected against short circuits over a wider range, so that in the event of a short circuit the entire bus system will not be destroyed. It is about providing.

According to the present invention, this problem is solved in the following manner based on the premise of a time division multiplex data transmission device having a bus system as described at the beginning.

In other words, in order to protect the bus line, a device is provided that detects short circuits and disconnects individual sections of the bus line, and the device that detects short circuits detects level fluctuations in the data line of the bus line (central bus line). A level sensor for detecting overcurrent is connected to the bus system as a subscriber, and an overcurrent breaker formed as a subscriber and having a control circuit device is provided as a device for interrupting the line section. The circuit breaker can be disconnected centrally by the level sensor in any data transmission cycle and can be disconnected in the next data transmission cycle depending on the closing command sent by the level sensor and for each line evaluated in the control circuit arrangement. It should be possible to supply electricity according to the amount of electricity in the section.

Advantageously, therefore, the line section connected to a subscriber which itself has been disturbed by a short-circuit or has a short-circuit in any position can be decoupled from the bus system, so that the rest of the bus system can still operate. It is.

Only the section of the bus line with the faulty or short-circuited subscriber is rendered inoperable.

A particularly advantageous embodiment of the invention is as follows, characterized in that, in order to protect the bus line, a device is provided for detecting short circuits and disconnecting individual sections of the bus line.

That is, a level sensor for detecting level fluctuations in the data line of the bus line is connected as a subscriber to the bus system, and each line section to be cut off is formed as a subscriber and has a control circuit. It can be switched off centrally by the level sensor in any data transmission cycle via one overcurrent breaker and evaluated in the control circuit according to the switching command sent by the level sensor in the next data transmission cycle. It can be applied according to the amount of electricity in each line section.

This device is particularly advantageous in bus systems with protected trunk systems that include non-interruptible subscribers and relatively fragile further line sections.

The level sensor for detecting level fluctuations is advantageously connected in this case to the data line of the bus line in the trunk system.

The level sensor and the overcurrent circuit breaker are in this case members of a bus system which transmits data in successive data transmission cycles.

As soon as the level change exceeds a predetermined permissible amount and is detected by the level sensor, all overcurrent cutoffs are activated to cut off the associated line section by advantageous command transmission.

This takes place regardless of whether the respective line section that can be interrupted by the overcurrent circuit breaker has a fault or not.

In the subsequent data transmission cycle, the level sensor identifies the signal level of the bus line in the mains system as fault-free and therefore commands all overcurrent circuit breakers to close.

However, only an overcurrent circuit breaker that re-energizes this line section depending on the electrical quantity that is evaluated in the control circuit of the overcurrent/current line breaker and provides an explanation for the short circuit in the respective line section Insert the interval.

By cutting off all fragile line sections, it is ensured that actually faulty line sections are also detected.

Subscribers connected to the mains system of the bus system and connected without an overcurrent circuit breaker remain active at all times.

Overcurrent circuit breakers, which protect subscribers to the mains system, can disconnect shorted dots and lines from the mains system.

For a dot with two terminals connected to the bus system, one overcurrent breaker is required for each terminal of the dot, whereas for a line with only one terminal connected to the bus system only requires one overcurrent breaker.

This fuse system eliminates to a considerable extent the effect of a short circuit on the data line of the bus line, since only the subscribers connected to the shorted line section are excluded.

Even if there are arbitrarily many short circuits in a line section that can be interrupted, the entire bus system will not fail.

The signal voltage level on the remaining bus system is not affected by a short circuit in any interruptible line section.

All subscribers of the signal bus system that must be particularly protected, such as, in particular, subscribers for level sensors, steering assistance and servo brakes, remain fully operational in the mains system.

A preferred embodiment of this device is as follows.

That is, a control circuit device that measures resistance between the data line and the ground line in order to form a control signal is provided in the overcurrent breaker, and the control signal and closing command are
They can be logically combined in a logic circuit device to become an input signal for inputting a line section.

In the event of a level fluctuation detected by the level sensor, it is therefore advantageous that this level sensor again sends out the switching command and the control circuit detects no short circuit by measuring the resistance in the disconnectable line section. A charging signal is sent to perform charging.

Therefore, a ground fault is detected for determining whether to switch the overcurrent breaker.

In a particularly advantageous embodiment of the device, the following is taken into account.

In other words, the overcurrent breaker control port/line device not only evaluates the polarity of the voltage on the data line of the line section that can be interrupted by the overcurrent breaker with respect to the energy line, but also issues a control signal depending on the polarity. This control signal can be logically combined with the closing command of the level sensor in a logic circuit arrangement to form the closing signal.

In this embodiment the following is advantageously utilized:

That is, the signal voltage level on the data line of the bus line is usually always lower than the positive battery potential that occurs on the energy line of the bus line.

In the overcurrent switch, the polarity of the voltage between the data line and the energy line is in this case a criterion for short circuiting the energy line, and the overcurrent breaker is also activated by logically combining the closing commands sent from the level sensor. Performs switching judgment.

Only when the voltage has a polarity representative of normal operating conditions will the overcurrent breaker switch be commanded to close.

In the event of a ground fault, the voltage between the data line and the energy line will be of opposite polarity, and in this case the voltage between the data line and the earth will be reversed in order to form a switching decision in conjunction with the closing command sent by the level sensor as described above. resistance is evaluated.

A control circuit which includes means for evaluating the polarity therefore also makes it possible to identify fuses in the bus system and short-circuits of the data lines to the supply lines in the case of this fault.

Advantageously, the energy line itself can also be protected by an overcurrent circuit breaker, with switch contacts operable by a switching signal arranged in the energy line.

Along with the disconnection of the short-circuit fuse by the overcurrent circuit breaker, the disconnection is effected in this case by the current supply to the subscriber of the disconnected line section.

In this case, it is advantageous if the subscriber is configured in such a way that it becomes inactive in the event of a lack of energy.

In more detail, the device with which the faulty line section can be cut off in the event of the above-mentioned faults is advantageously as follows.

That is, in the overcurrent breaker, one switch is arranged in each of the energy line and the data line, and a connection is made from the terminal of the switch in the energy line connected to the energy source to the evil leg circuit device. A connection is made to the control circuit device from a terminal connected to the level sensor and a terminal connected to the disconnectable line section in the switch in the mutator line.

In order to enable the device to operate even when the energy line is short-circuited to earth, the device is first further adapted by means of a fuse located in the energy line on the side of the overcurrent circuit breaker connected to the energy source. It has become.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the subscribers of the bus system are indicated by numbers 1 to 5, and these subscribers are located in fragile areas.

The respective subscribers 1, 2, 3 and the subscribers 4 and 5 are connected via respective line sections 6, 7, 8, 9 of the bus line to a central bus line 10 arranged in a non-fragile mains system. has been done.

Between the common connection point 11 and the line section 6 or between the connection point 11 and the line section 7, a resistor 13 or 14 is respectively arranged near the connection point.

Similarly, a resistor 15 is arranged between the central connection point 12 and the line section 8, and a resistor 16 is arranged between the connection point 12 and the line section 9.

Since each resistor is connected close to the connection point, partial short-circuits in line sections 6, 7, 8, 9 that are further away from the resistors are detected.

If a ground fault occurs in the line section 6 at location 17, a voltage drop will occur across the resistor 13, which voltage drop will be approximately equal to the voltage present on the central bus line 10.

The short-circuit current caused by the ground fault in location 17 is then limited by resistor 13, so that the voltage level on central bus line 10 drops, but does not become so low that subscribers 2, 3, 4° 5 can no longer operate. .

Therefore subscriber 1 is only rendered inoperable.

Subscribers directly connected to the central bus line 10, which are not specifically illustrated, can thus remain operational.

Second or other location where ground fault is possible 18°19.20
Even when such a ground fault occurs, the bus system shown in FIG. 1 can still operate at a low voltage level on the bus line 10.

By the resistances 21 and 22 shown in broken lines in Fig. 1,
It has been shown that the central bus line 10 itself can also be protected section by section by current limiting resistors.

Instead of the individual resistors shown in FIG. 1, the individual line sections may also be constructed from resistance wires.

The lines schematically shown in FIG. 1 are bus-based data lines.

The bus system according to FIG. 2 is to a large extent the same as the one according to FIG. It is connected to the central bus line 10.

In addition to those in FIG. 1, a further subscriber 23 is connected to the line section 8, and a further subscriber 24 is connected directly to the central bus line 10.

The subscribers 24 and the central bus line 10 are in a fragile trunk system 25, which is shown in broken lines.

The line sections 6, 7, 8, 9 are connected to the central bus line 10 via overcurrent circuit breakers 26, 27, 28, 29 instead of resistors.

These overcurrent circuit breakers constitute subscribers of the bus system.

Furthermore, within the trunk system 25, a level sensor 30 is connected to the central bus line 10, which level sensor is also a subscriber to the bus system.

Fragile line sections 6, 7, 8°9 indicated by thick lines are
It is protected against the main line via an overcurrent breaker.

If the signal level on the central bus line 10 falls below a certain minimum value (short circuit in the extreme case), protection is provided in such a way that all overcurrent circuit breakers disconnect the associated line section from the mains system; is detected by a level sensor.

The level sensor issues a disconnection command by means of an advantageous command transmission so as to immediately disconnect the line section.

In the data transmission cycle following the disconnection, the level sensor generates a power-on command, which, however, causes only the power-on of the disconnected line sections that are free of faults or short-circuits.

For this purpose, in addition to the closing command, the overcurrent circuit breaker evaluates the electrical quantities of the associated disconnected line section, namely the resistance of the data line with respect to the earth line and the polarity of the voltage of the data line with respect to the energy line. Logically combined with input instruction.

The fault-free line sections are then switched on again, while the faulty line sections remain disconnected and the central trunk system with the level sensor 30 and the subscriber 24 remains in operation at all times.

The arrangement of the overcurrent circuit breaker in the bus line consisting of the data line 1i31, the ground line 32 and the energy line 33 is shown in FIG.

An overcurrent circuit breaker 34 is shown within the dashed line.

The overcurrent breaker is a control circuit device 3 including a logic circuit device.
5, and one switch 36 in the data line and a switch 37 in the energy line, which is connected on the left to a battery (not shown).

There is also a central bus line (not shown) on the left side of Figure 3.
A data line 31 branches off from this central bus line.

In order to transmit the input command to the control circuit arrangement, this control circuit arrangement is connected to the data line by means of a terminal 38 which is connected to a level sensor.

In order to evaluate the electrical quantity of the line section on the right side of FIG. 1 to be switched off and switched on, the control circuit arrangement is connected to the terminal 39 of the data line which can be switched off.

Furthermore, the control circuit arrangement is connected to a terminal 40 on the energy line 33 on the side of the switch 37 closer to the battery.

Data line 3 to ground line 32 or energy line 33
In the event of a short circuit of 1, the control circuit arrangement receives a cutoff command from the level sensor via the data line 31, which allows the hitherto closed switches 36 and 37 to be opened.

When an input command occurs via data line 31 and terminal 38 in a subsequent data transmission cycle, the control circuit arrangement
The switches 36 and 37 are not immediately closed, but the electrical quantity of the cut-off line section is first evaluated.

For this purpose, the resistance between the terminal 39 and the terminal 41 of the ground wire is evaluated, and only when a predetermined resistance value is exceeded forms a control signal for re-closing in conjunction with the closing command.

Furthermore, the condition is utilized that in fault-free operation the potential of the energy line is always more positive than the potential of the data line.

If no such voltage is detected between the terminal 40 and the data line, the control circuit arrangement generates a control signal that forms a closing command for the switches 36 and 37 in conjunction with a closing command that is combined with a control signal in the logic circuit. Does not form a signal.

Therefore, the control circuit arrangement must not detect a fault due to a short circuit either to the earth line or to the energy line in order to re-energize the disconnected line section.

In contrast to the device according to FIG. 1, the device according to FIG. 3 also protects the energy line against short circuits in that it can be switched off by switch 37.

If a fuse 42 is placed in the energy line for further protection, then the overcurrent breaker will be able to operate in the event of a short circuit of the energy line to earth.
This fuse is placed between the overcurrent switch and the battery, not shown.

In the arrangement shown in FIG. 4, the two sections of the central bus line of the bus system are designated 10a and 10b.

An energy source 43 in the form of a battery is connected to the central bus line and to section 10b.

Furthermore, the central bus line includes a central subscriber module 44.

Two lines of the bus system branch from each end 45, 46 of the central bus line.

The lines connected to end 45 are designated 6, 7 and the lines connected to end 46 have numbers 8, 9.

Each line connects at least one subscriber module 1
-It is familiar with 4.

The lines 6 , 7 are connected via a first fuse module 47 to the end 45 of the central bus line.

The fuses 48.49 in the fuse module represent that each 86.7 is protected within the fuse module for the section 10a of the central bus line.

Similarly, the lines 8, 9 are connected to the end 46 of the central bus line via a second fuse module 50 with fuses 51, 52.
It is connected to the.

This device is such that in the event of a short circuit in one of the wires 6, 7, 8.9, each wire is disconnected from the other wires and the central bus wire by one of the fuses 4B, 49° 51.52. The short-circuit is therefore limited to the faulty line in each case.

Of course, a fault due to a short circuit in section 10a of the central bus line will also spread to lines 6 and 7, and likewise a short circuit in section 10b will spread to lines 8 and 9.

The aforementioned limitation of the effectiveness of the protection in the device according to FIG. 4 is prevented by the device according to FIG.

In this configuration of the bus system, the central part is replaced by the central bus line shown in FIG. 4 as follows.

The fuse modules 47, 50 thus form a unit with the central subscriber module 44, so that there is no central bus line section between the fuse module and the central subscriber module.

Here the energy source 43 is the central subscriber module 44
connected directly to.

In the configuration according to FIG. 5, the respective fault due to a short circuit occurring in one of the lines 6 to 9 is limited to this line.

Since there is no central bus line, such central bus line disturbances do not affect the line.

The fuse module can cooperate with a level sensor that detects level fluctuations on the data line at the central bus line or at the central subscriber.

The level sensor is therefore connected to the bus system as a separate subscriber.

Each of the lines 6 to 9 can be disconnected centrally by a level sensor in any data cycle via an overcurrent circuit breaker formed as a subscriber in one of the fuse modules with the control circuit arrangement; In addition, it can be turned on in response to a turn-on command sent by the level sensor in the next data transmission cycle and in accordance with the electrical quantity of the respective line that can be evaluated in the control circuit arrangement.

In particular, a control circuit arrangement is provided which measures the resistance between the data line and the ground line in order to form a control signal in the overcurrent circuit breaker.

The control signal and the input command for the input signal for inputting the line can be combined in a logic circuit arrangement.

Furthermore, the control circuit arrangement of the overcurrent breaker is designed to, in addition to evaluating the polarity of the voltage on the data line of the line that can be interrupted by the overcurrent breaker, generate a polarity-dependent control signal with respect to the energy line. This control signal can be combined with the activation command of the level sensor to form the activation signal in the logic circuit arrangement.

Furthermore, the fuse in the energy line can be provided on the side of an overcurrent breaker connected to the energy source.

[Brief explanation of the drawing]

FIG. 1 is a diagram of a device providing partial protection by resistors;
2 is a diagram of a device for partially protecting particularly dangerous subscribers by overcurrent circuit breakers and level sensors; FIG. 3 is a diagram of the arrangement of overcurrent circuit breakers in bus lines; FIG. A diagram of a device with a protected central bus line, FIG. 5 is a diagram of another device with a central subscriber module. 1.2,3,4,5...subscriber, 6,7,8゜9...line section, 10...chuo bus line,
13,14゜15.16,21.22... Resistor, 26,27゜28.29... Overcurrent breaker, 30... Level sensor, 31... ...Data line, 32...Ground wire, 33...
energy bird

Claims (1)

[Scope of Claims] 1. A bus system includes a bus line and a plurality of subscribers connected to the bus line, and these subscribers are connected to perform data transmission with each other in a predetermined order and in a predetermined combination. Each subscriber has at least one programmable counter, the counting input of which is provided. is connected to a clock generator and the output terminal of this counter makes a data transmission connection between the bus line and the data sending or receiving terminal of this subscriber;
In time-division multiplex data transmission equipment with a bus system, which is connected to a switching device and in which the counters of all subscribers are synchronized with each other, short circuits can be detected and A device is provided to cut off each section, and as a device to detect short circuits,
A level sensor 30 that detects level fluctuations in the data line (Fig. 3 31) of the bus line (Central Lotus Line 10) is connected to the bus system as a subscriber. Overcurrent circuit breakers 26, 27, 28, 29 are provided, which are configured as 26, 27, 28, 29 and have a control circuit arrangement, which can be centrally disconnected by a level sensor in any data transmission cycle and which In response to the closing command sent by the level sensor in the next data transmission cycle and depending on the electrical quantity of the respective line section 6°7.8, 9 evaluated in the control circuit arrangement, it is possible to close it. A time division multiplex data transmission device having a bus system, characterized in that: 2 Data line 31 and ground line 3 to form control signals
A control circuit device 35 for measuring the resistance between line sections 20 and 20 is provided in the overcurrent breaker 34, and the control signal and the closing command are logically combined in a logic circuit device so as to become a closing signal for closing the line section. A device according to claim 1, which is possible. 3. The control circuit arrangement 35 of the overcurrent breaker 34, in addition to evaluating, with respect to the energy line, the polarity of the voltage on the data line 31 of the line section which can be interrupted by the overcurrent breaker 34, also generates a control signal depending on the polarity. 3. The device as claimed in claim 2, wherein the control signal is logically combinable with a closing command of the level sensor 30 in a logic circuit arrangement to form a closing signal. 4 In the overcurrent breaker 34, one switch 36, 3 is installed in the energy line 33 and the data line 31, respectively.
7 is arranged and from the terminal 40 of the switch 37 in the energy line connected to the energy source to the control circuit arrangement 3
5 and switch 3 in the data line.
3. The device according to claim 2, wherein the connection to the control circuit arrangement is made from a terminal 38 connected to the level sensor at 6 and a terminal 39 connected to the disconnectable line section. 5. The device according to claim 1, wherein a fuse 42 is provided in the energy source 33 on the side of the overcurrent breaker 34 connected to the energy source.