KR100371248B1 - Electronic safety devices for passenger cars - Google Patents

Abstract

The present invention relates to an acceleration sensor (200), a control device (201), a plurality of inertia prevention devices (31/1, 31/6), and output stages (30/1,. The electronic safety device for a passenger (1) of a passenger (1) having a safety device (30/6), wherein the secure operation of the safety device is ensured as follows. That is, a characteristic error state is stored at the same time as the control method for compensating the error state, and in case of error, each control method applied for the operation of the inertia prevention device.

Description

Electronic safety devices for passenger cars

In EP0284728, passenger safety devices are known. The safety device has a plurality of ignition fills for triggering a plurality of safety means for passengers, e.g., an airbag, a seat belt tensioner, etc., and their safety means, respectively. The current through these ignition peaks is used from a limited energy reserve. In order to limit the current flowing through each of the ignition fills, the condenser is connected in series to each ignition coil. This capacitor allows current to flow through the ignition coil only until it is charged to the voltage level of the energy reserve.

A passenger electronic safety device is also known from US-PS 51464104, which is the basis of the present disclosure. This device likewise has a capacitor connected in series to the ignition coil. However, this capacitor has a small capacitance and is not sufficient to ignite the ignition charge as the charge of this capacitor at the maximum voltage. In order to ignite the ignition coil, a high current is also required. This current is firstly driven by a capacitor charged and connected in series to the ignition coil through the ignition coil. The latter type of safeguard is particularly robust against unwanted error triggers. This is because the ignition of the ignition coil does not reach the one-time current passage due to the amount of the charge existing in the capacitor. Also, for example, if it is determined that the airbag should not be triggered due to a relatively minor risk of an accident, the ignition process of the ignition charge already initiated can be discontinued.

The present invention relates to an electronic safety device for a passenger in a vehicle according to the superordinate concept of claim 1. Electronic safety devices for vehicle passengers are described, for example, in publication 1141 Ingenieur de l'Automobile (1982) no. 6, pp. 69-77. This type of safety device should always be ready for operation in order to protect the life of passengers in the event of a serious accident. This always ready for operation should always be monitored by appropriate inspection procedures. These inspection procedures shall include as many structural elements as possible of the safety device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are shown in the drawings and described in detail below.

1 is a block circuit diagram of a safety circuit of the present invention;

Figure 2 is a table of control indications that depend on error conditions and errors;

Figs. 3 to 7 are timing diagrams for explaining a predetermined error state and a control process occurring therefrom. Fig.

8 is a flow chart for describing an airbag trigger obtained from error identification and error identification;

9 is a block circuit diagram of a safety device having a plurality of inertia prevention devices and an output stage attached thereto.

10 is a view showing a first embodiment in which an ignition charge is arranged in an entire bridge circuit at an output stage constituted by an integration technique;

11 is a view showing a second embodiment in which an ignition fill is arranged in a 3/4 bridge with an output stage configured by an integration technique;

12 is a view showing a third embodiment in which an ignition coil is arranged in a half bridge as an output stage configured by integrated technology;

13 is a timing chart corresponding to the output stage shown in Fig.

Figs. 14 to 16 show an embodiment of a separate output stage including a reference path. Fig.

By means of the solution of the invention described in the characterizing part of claim 1, particularly effective monitoring of the safety device is possible and thereby high operational readiness is ensured. Particularly, the operation of safety means such as an airbag and / or a seat belt tensioner is achieved as follows. That is, the characteristic of the error is stored in the table at the same time as the control instruction, and even if a predetermined error occurs by the control instruction, the reliable trigger of the airbag is guaranteed.

The usability of the airbag device according to the configuration of the safety device shown in the block circuit diagram of Fig. 1 is remarkably improved even when there are many difficult error conditions. Whereby a reliable trigger of the airbag is always achieved even under very unfavorable operating conditions. Thus, for example, short circuiting of the vehicle body to the positive terminal of the voltage source also can not prevent precise ignition of the ignition fill. With this circuit configuration, the switch elements T1, T2 and T3, T4 to T5 and T6 are operated in a push-pull manner. Thus, even when the usable supply voltage is relatively low, a sufficiently high voltage deviation can be obtained from the ignition circuit capacitors CF and CBF. This ensures reliable operation of the airbag safety means at 9V to 16V even when the battery voltage is relatively low. In addition, safety devices can be configured without additional energy reserve and additional voltage converters if necessary for cost reasons. The supply pressure EV may be detected, for example, prior to the start of the ignition process, and optionally detected during the course of the ignition process at another advantageous time interval (e. G., An interval of 1 ms each) It is possible to make the control of the device suitable for each instantaneous condition. That is, it is possible to apply a substantially constant ignition current to the ignition coil in this way. As a result, the safety against the error trigger is significantly increased. Since the average ignition current flowing through the ignition coil per operating clock (T) can be maintained at a favorable average value of about 2A, it is not undesirable to be triggered even if the ignition coil is controlled to 20 clock cycles erroneously. In addition, the proposed safety device can handle ignition energy extremely wastefully. This is for the purpose of forcibly controlling the ignition fill and reliably triggering the airbag in a predetermined error state. This is particularly the case when the ignition fill is short-circuited and the bypass circuit of about 0.5? To 1? Is attempted to keep it normal to supply sufficient ignition energy to the ignition fill. In the case of such an error, the proposed circuit configuration can greatly increase the current passing rate in order to cause ignition, in a corresponding and appropriate manner of operation. Another special case is the case of ignition circuit breakdown, and this breakdown becomes a resistance of about 10?. In such a case, it is advantageous to obtain a sufficiently large ignition by causing a sufficiently large voltage deviation to occur in the capacitors CF and CBF of the ignition circuit by appropriate early operation. In order to detect the instantaneous error condition of the safety device even at the ignition time, it is possible to select an advantageous operation form in order to achieve an advantageous trigger action corresponding to the existing situation, by selecting an appropriate control strategy. It is also particularly advantageous to re-examine the already selected control method if necessary, and to change it again if another control method appears to be more advantageous. For example, it is possible to check whether or not the control method selected for the detected irritation condition is appropriate or not, at intervals of about 1 mu s after the selection of the predetermined control method. If it is not suitable, it can be converted in accordance with the control method which is adapted according to the elapse of the next operation clock. Therefore, the safety device of the present invention can appropriately use the ignition energy. This is very important if the vehicle battery is already consuming and you can only use very limited energy reserves. A great advantage is also obtained in the case of a so-called double error in the ignition circuit area. In this case, in the predetermined duration of the triggering process, Time is to use an optimal method for compensating for the second error. For example, a duration of about 1 ms may be used to eliminate the first error state for the first method, and a separate 1 ms duration may be used to eliminate the second error state for the second method. have.

As a particularly advantageous configuration of the present invention, the error condition identified by regularly checking the safety device can be stored in the memory area of the microcontroller. If it is necessary to trigger the safety means in relation to the accident situation later in time, this stored error state can be called and considered when selecting an appropriate control method for controlling the ignition fill. Therefore, for example, when an error occurs suddenly during the triggering process, a first control method for compensating for an abruptly occurring error condition is selected for a time period of, for example, 4 msec, It is possible to select another control method considering the error condition stored in the memory.

1 shows a block circuit diagram of a passenger safety device according to the present invention. This safeguard is deployed in vehicles, advantageously on land vehicles such as private cars or lorries, and is used to protect passengers by operating safety means such as a critical warning airbag and / or seat belt tensioner. The safety device is connected to the battery 10 of the vehicle, from which current is supplied. A voltage divider including resistors R1 and R2 is connected to the battery 10 in parallel. The tabs of the voltage dividers R1 and R2 are connected to an input terminal (analog / digital input side) of the microcomputer 20 through a line UBM. The voltage value can be taken out to monitor the voltage of the vehicle battery 10 from the voltage dividers R1 and R2 through the line UBM. Normally, the minus terminal of the vehicle battery 10 is connected to the earth terminal of the vehicle. An input terminal of the DC voltage converter 11 is connected to the positive terminal of the vehicle battery 10. The output side terminal of the converter is connected to the plus terminal of the energy reservoir 12, and the minus terminal of the energy reservoir is similarly connected to the earth terminal. As an energy reservoir, a relatively large capacity, for example, a capacitor of several thousand μF is suitable. The energy reservoir 12 is provided so that current is supplied to the electronic safety device even if the connection to the vehicle battery 10 is lost in the event of an accident or for at least a limited time. Advantageously, the energy reservoir 12 is charged by the DC voltage converter 11 to a voltage several times the voltage of the vehicle battery 10. For example, if the on-board power source of the vehicle is configured for about 12V by direct current, the energy reservoir 12 is charged to, for example, 45V to 50V. The plus terminal of the vehicle battery 10 is connected to the starting point of the second voltage dividers R3 and R4 via the electrodes 13 and 14 arranged in the conduction direction in the same manner as the plus terminal of the energy reservoir 12, The origin is likewise grounded. The tabs of the voltage dividers R3 and R4 are connected to the second input terminal (analog / digital conversion) of the microcomputer 20 through the line EVM. Through this line EVM, the partial voltage can be taken out to monitor the voltage applied to the voltage dividers R3 and R4. The first switch terminal of each of the switch elements T1 and T2 is connected to the connection point of the diodes 13 and 14. The second switch terminal of each of these switch elements is connected to two diodes 15, 18 connected to each other. A first ignition coil (ZPF: for driver's airbag, for example) and a first condenser CF are connected in series between the cathode terminals of the diodes 15 and 17. A second ignition coil (for ZPBF, for example, for a passenger seat) and a second condenser CBF are connected in series between the cathode terminals of the diodes 16 and 18. A first switch terminal of another switch element T3 is connected to a connection point between the cathode terminal of the diode 15 and the ignition coil ZPF and the second switch terminal of the switch element T3 is grounded. A first switch terminal of the switch element T4 is connected to a connection point between the cathode terminal of the diode 16 and the ignition electrode ZBPF and the second switch terminal of the switch element is grounded. The first switch terminal of the switch element T6 is connected to the connection terminal between the cathode terminal of the diode 18 and the capacitor CBF, and the second switch terminal of the switch element T6 is grounded. The control terminals of all the switching elements T1, T2, T3, T4, T5 and T6 are connected to the corresponding output terminals of the driver circuit 21 via the connection lines PushR1, PushR2, Pull1F, Pull1BF, Pull2F and Pull2BF . This driver circuit is connected to the output terminal of the microcomputer 20 via the corresponding bus line 19 and is controlled thereby. The ignition pillars ZPF and ZPBF are thermally coupled to the airbags 22 and 23 installed as safety means against passengers, in detail, not shown. The thermal action bonding means that the ignition pill (ZPF, ZPBF) which can be heated by current passage can operate the gunpowder which inflates the airbags (22, 23) in the heating state.

The function of the safety device shown as a block circuit diagram in Fig. 1 will be described below with reference to another drawing. Fig. 2 shows a control instruction depending on error conditions and errors which can be safeguarded in the form of a priority table. By this control instruction, a reliable trigger of the airbags 22, 23 is achieved even in an error state. The error conditions and error-dependent control indications are advantageously stored in the memory device 202. The memory device may be a constituent member of the microcomputer 20. Various error conditions are written in the first column of the table. In detail, the following various error conditions are handled.

- Short circuit (KS) at the plus terminal of the vehicle battery (10) or at the circuit point (FP or BFP) of the energy reserve (12).

- Short circuit at the plus terminal of the vehicle battery (10) or the circuit point (FM or BFM) of the energy reserve (12).

- Circuit point (FP or BFP) to ground.

- Circuit point (FM or BFM) to ground.

- short of capacitor (CF to CBF).

- Short circuit of ignition fill (ZBF to ZPBF).

- Disconnection of ZKF or ZKBF.

- Currently no error.

In the third column below, control instructions assigned to each error state are written. These control instructions also depend on the supply voltage used at the moment, i.e. whether the supply voltage is between 9V and 24V, between 24V and 30V, between 30V and 45V. In practice, a characteristic map that depends on the error state and the height of the supply voltage is handled as an input parameter. By this characteristic map, it is possible to perform very high-speed error diagnosis and control of very effective ignition charges (ZPF, ZPBF) depending on the error state and the height of the supply voltage, and furthermore, to operate the airbags 22 and 23. For illustrative purposes, the two matrix fields of FIG. 2 are used as examples. For example, it is assumed that a short circuit is detected at the circuit point (FP or BFP) in the positive pole of the vehicle battery 10 or the energy reserve 12 (see the first stage of the table, the error state of the first row). A different control method is taken depending on the height of the supply voltage EV that exists instantaneously. This is for sufficiently applying the ignition current to the ignition pillars ZPF and ZPBF even when the error state is identified, and to reliably trigger the airbags 22 and 23. [ If the supply voltage EV is in the voltage range of 9V to 24V, the control method (MOD 3.1) is taken (see the first step in the table of Fig. 2, row 4). This will be described in detail later with reference to Fig. The control method (MOD 1.1) is taken when the supply voltage is between 24V and 30V, and in the case of the error state described above (see the table of FIG. 2, the first row, third row). This will be described in detail later with reference to Fig. Also, when the supply voltage is between 30 V and 45 V and the error state is described previously, a control method of MOD 1 is taken (table in Fig. 2, first row, second row). This will be described in detail later with reference to Fig. Corresponding is also appropriate for other positions in the table shown in Fig. 2 which will also be described later.

First, the control method (MOD 1) will be described in detail with reference to FIG. This control method is identified in the table of Fig. 2 as being short-circuited at the positive terminal of the vehicle battery 10 or the energy reserve 12, the circuit point (FP or BFP) of the block circuit diagram of Fig. 1, EV is detected in a region between 30V and 45V (see the table of FIG. 2, second row of the first step). If the same control method is also shown in a separate place in the table of Fig. 2 (refer to the third row, the second row and the fifth row, second row) and a short circuit to ground is detected at the circuit point (FP or BFP) CF or CBF) is detected.

The control method according to MOD 1 (see Fig. 3) is advantageous when the positive terminal of the voltage supply source is short-circuited between the circuit points FP and BFP. In this case, an error situation in which a short circuit occurs between the circuit point (FP or BFP) or a short-circuit to the positive electrode of the supply voltage at the circuit point is covered. In these cases, the voltage deviation of the capacitors CF and CBF in the ignition circuit does not depend on the height of the voltage of the vehicle battery 10. Therefore, the duration of current passing through the ignition pill (ZPF, ZPBF) is not affected by an error short circuit to the positive terminal of the voltage supply unit. Therefore, even if the current passing rate through the ignition pillars ZPF and ZPBF changes due to a short circuit to the positive polarity of the supply voltage, the trigger delay time of the airbags 22 and 23 There is no change. Figure 3 shows an important signal pattern for the control method (MOD 1). In this figure, it is assumed that the minimum inductance of the ignition circuit is 2 [mu] H to ignite. The capacitors CF and CBF arranged in the ignition circuit are connected to the positive terminal of the voltage supply part existing in the circuit point FP or BFP depending on the case by the conduction controlled switch element T2 (control line PushR2) It is charged against short circuit. In this case, the switching elements T3 and T4 can be additionally controlled to be turned on (control line (Pull1F, Pull1BF)). This is to connect a circuit point (FP or BFP), which is not short-circuited, to a ground in a predetermined manner against a short circuit to a positive voltage terminal. It is also possible to control the short-circuit situation in which the input is coupled through the diode by this. In Fig. 3B, it is found that the control of the switch element T2 is performed at the clock, for example, at the time point t1 of the time axis t . The switch element T2 is then subjected to conduction control in a time period of about 7 mu s. Subsequently, the switching element T2 is blocked again in the time period of 7 占 퐏, as is seen in Fig. 3b, and is then subjected to conduction control in a time period of 7 占 퐏, which is newly ignited. The time phase in which each conduction is controlled is performed at the time interval T. [ 3C, the switch elements T3 and T4 are additionally controlled to conduct between the conduction phases of the switch element T2, respectively. Thereafter, the switch element T2 is blocked (corresponding to T3 and T4 as occasion demands) by the corresponding control on the control line (PushR2, Pull1F, Pull1BF) belonging thereto and the switch elements T5 and T6 Is controlled to be conductive. The conduction phases of the switching elements T5 and T6 start at a time point t2 and continue for about 7 mu sec similarly. According to this control, the capacitors CF and CBF arranged in the ignition circuit are charged in the opposite direction. Fig. 3E shows the current pulses IZKF and IZBF as a function of time. These current pulses are generated by the control of the ignition circuit described above and are applied to the ignition charges ZPF to ZPBF. It is easy to know how many current pulses of this kind are required to operate the ignition coil because the amount of energy necessary for reliable operation of the ignition coil is already known.

The control mode (MOD 1.1) will be described with reference to FIG. This mode is used in the table of Fig. 2, for example, if a short circuit to the positive terminal of the supply voltage is present at the circuit point (FP or BFP) (first row, third row of the table) This applies to the case where there is a point (FP or BFP) (third column in the table, third row). In operation according to MOD 1.1, it is considered that the supply voltage is reduced to a value between 24V and 30V. With these parameters, the ignition control can be adjusted as follows. That is, the current passing rate of the ignition coil can be adjusted so as to be accurately maintained in the predetermined region. Here, one type of pulse width modulation is proposed for controlling the current conduction rate in ignition of the airbag apparatus. The instantaneous value of the supply voltage is then also taken into account during an accident and during the ignition process of the ignition coil. It is not necessary to put it back into the signal line shown in Fig. This is because the line substantially corresponds to the signal lapse in Fig. 3 already described in the operation, except that the control time is slightly different. Switch elements T1 to T6 are controlled in MOD 1.1 as well as MOD 1.1 as follows. That is, if the voltage characteristic allows, a current of about 5A (IZKF, IZKBF) flows at maximum. The operation modes of MOD 1 and MOD 1.1 are suitable for control when the circuit point (FP or BFP) is short circuited to ground but output loss (output loss) is not occurring. The above operation mode is also suitable for the case where the capacitors CF and CBF are short-circuited but there is no significant output loss. Because it can provide about 2,5 A of ignition current required for its operation.

Next, the control method (MOD 3.1) will be described based on Fig. This mode of operation takes into account that the supply voltage is decreasing to a voltage range of about 9V to 24V. This state is, for example, when there is an excessively long time until a failure occurs in the energy reserve 12, or a serious accident continues after the destruction of the vehicle battery 10. There are also situations where safety devices must be able to run without energy reserve or DC voltage converters. In the unfavorable case of shorting to the positive terminal of the supply voltage, a small voltage deviation of about 6 V remains in the capacitors CF and CBF of the respective ignition circuits. Therefore, considering the inductance of about 2 μH of the ignition circuit, An ignition circuit current of about 2A is obtained. This is made possible by control of the optimum control in the resonance region of the ignition circuit and the switch elements T1, T2 to T3, T4 and T5, T6 that are operated by the push-pull operation proposed here. Thus, even in the worst case, a voltage deviation of about 12 V can be prepared in the capacitors CF and CBF of the ignition circuit.

Hereinafter, the second method (MOD 2 and MOD 2.1) will be described in detail with reference to FIG. 6 and FIG. This type of operation is particularly advantageous when the circuit point FM of the driver's airbag and / or the circuit point BFM of the passenger's seat airbag is short-circuited at the plus terminal of the supply voltage. In this case also, the voltage deviation in the capacitors CF and CBF does not depend on the height of the battery voltage UBat (about 9V to 16V) of the vehicle battery likewise. Accordingly, the current passage time of the ignition charges (ZPF, ZPBF) is not affected by the error shorting of the supply voltage to the positive polarity. This type of operation is possible by the safety device shown in Fig. 1 having two separate controllable switch elements T1 and T2 at the ignition output. The discussion of the curve progressions shown in Figs. 6 and 7 is omitted. This is because it is possible to apply almost exactly the detailed description of the operation types (MOD 1 and MOD 1.1). The operation modes (MOD 2 and MOD 2.1) are likewise suitable for control when the circuit points FM to BFM are erroneously short-circuited to earth, but no output loss is seen. Similarly, it is also suitable for the control of the ignition circuit when there is no error.

The mode of operation (MOD 2.2) is particularly suitable as a control method when the safety device identifies a short of the ignition fill (ZPF, ZPBF) of the ignition circuit. If this short-circuit has a value different from 0 OMEGA and, for example, it is in the range between 0 OMEGA and 1 OMEGA, the ignition peaks ZPF and ZPBF are controlled by the corresponding clock control (pulse width modulation) It is advantageous to apply the maximum possible current passing rate. Assuming that the inductance of the ignition circuit is 2 mu H, the resonance point is adjusted by the control duration of about 6 mu s. When the short circuit resistance value is about 0.5 OMEGA, a current of about 1A flows in the ignition coil. A small supply voltage on the order of 24 V to 30 V is used when a high current passing material is required to flow through the ignition coil for an error condition (residual resistance of about 0 Ω to 1 Ω) The voltage shift in the capacitors CF and CBF of the ignition circuit is doubled by the two switch elements T1 and T2 operating in the push-pull operation. This allows a limited maximum current to flow. By limiting the use of this mode of operation to a relatively low supply voltage, unnecessary high block voltages do not occur in the switch elements. This makes it possible to use discrete semiconductor elements or integrated semiconductor elements which are very inexpensive as a switch element. The operation type (MOD 3) is likewise particularly suitable for the case where there is an open circuit in the ignition circuit. This error condition is assumed, for example, when the resistance of the ignition circuit exceeds a value of about 10 [Omega]. In the case of such a high ignition circuit resistance, sufficient voltage deviation in the elements of the ignition circuit (ignition charges, capacitors) is taken into account in time so that the ignition current is maintained at a minimum required value of about 2A. This is achieved by the push-pull operation of the switch elements T1, T2 to T3, T4 and T5, T6.

The operation progress of the safety device of the present invention will be described again with reference to the flowchart shown in Fig. Assuming that the vehicle equipped with the electronic safety device is in an operating state and is involved in road traffic (step 8.0), signal evaluation is performed in process step 8.1. That is, the signal recorded by the acceleration sensor 220 is evaluated by the microprocessor 20. Here, it is detected whether or not the signal indicates a serious accident situation such as (8.2) requiring the triggering of the airbags 22, 23 or not. If this is not detected (8,3) the signal evaluation is continued (8.1). If an accident situation is identified (8.4), the ignition circuit in an instant. It is checked whether a double error exists (8.6) or not (8.5).

If an instantaneous ignition circuit double error is identified (8.6), a control method suitable for the optimal error is selected from the table of FIG. 2 (8.7). Next, a predetermined control time (adjusted to the error type initially identified (8.8)) is performed, for example, for about 1 ms. Following this, (8.9), the control method is changed (selected from the table of FIG. 2). This is to adjust for the second identified error in a separate time of about 1 ms. If no instantaneous ignition circuit double error is identified at the time of the test, according to step 8.10, the optimum control method corresponding to the momentary ignition circuit condition is selected from the table of FIG. Subsequently, (8.11), the control of the ignition fill is performed in accordance with the optimum control method. In step 8.12, the instantaneous ignition circuit conditions are checked (e.g., short-circuit identification) at a measurement interval of about 100 μs, and the available supply voltage is measured. In step 8.13, Is checked. Alternatively, loops 8.13, 8.15, 8.16, 8.17 and 8.18 or loops 8.13, 8.19 and 8.20 may be repeatedly processed. In step 8.21, it is additionally detected whether or not there is an occasionally stored error condition, otherwise (8.22), the overall trigger duration is less than a predetermined limit duration (TG, about 8 ms) Is checked (8. 23). In a small case (8. 24), return to 8.4 in the branch point (C). Otherwise (8.2.25), the triggering process ends at 8.26. If there are any memorized errors (8. 27), it is again asked whether there is an ignition circuit double error or not. Alternatively, branches to 8. 29, 8. 30, 8. 31, and 8. 32 are ultimately done to return to the main route at 8.33. In this main route, the trigger ends at 8.40. If the ignition circuit double error is not identified (8.34), (8.35) again the optimal control mode is selected from the table of FIG. The corresponding trigger is done in 8.36.

Fig. 9 is a block circuit diagram of an alternative embodiment of the safety device 1. Fig. In this embodiment, the safety device 1 is provided with a sensor 200, a control device 201 having a memory device, and a plurality of inertia prevention devices 31/1, 31/2, 31/6, (30/1, 30/2, ..., 30/6) that are attached to the input / A plurality of output stages and an inertia prevention device of this kind are, for example, previously assumed in a modern automobile equipped with the following safety device. Driver seat belt Tensor, seat belt for passenger seat Tensioner, driver airbag, passenger airbag, driver side airbag, passenger side airbag. At present, the following tendencies are already seen. That is, there is a tendency to exceed the number of six inertia prevention devices shown in the example of Fig. 9 to six output stages attached. In the event that such a safety device is mounted on the rear seat of a vehicle, a plurality of inertia prevention devices and output stages are also used in the future. The output stage 30/1, 30/6 is, as in the embodiment shown in FIG. 10, relatively complex in its own right. A plurality of switch elements T11, T12, T13 and T14 are connected in series and in parallel. It will be appreciated by those skilled in the art that the embodiment of Fig. 10 is a bridge circuit referred to as a full bridge. It is also possible to think of a simple variant embodiment, for example a so-called 3/4 bridge, or a 1/2 bridge. These are shown as examples in Figs. 1 and 12. Fig. From the reasons of rationalization and reliability, it is conceivable to manufacture the output stage described above, at least a major part thereof, in an integrated form. For example, it is advantageous to construct at least the switch element described above as a semiconductor switch and manufacture it by an integration technique. This is possible without any problem if the switching element is formed as a power MOSFET transistor by the present technical means. However, only the following semiconductor switch elements can be manufactured as a current process for an integrated circuit. That is, it is possible to manufacture only an element in which the transfer resistance is in the conduction state of about 0.5? To about 1.5?. Therefore, the on-resistance of the switch element is on the order of the resistance of the conventional ignition fill, and the ignition fill has a resistance value (for example, 1 to 30) on the order of several ohms. However, with this resistance characteristic, a normal ignition circuit inspection method using a discrete power MOSFET can not be applied well. That is, the resistance value of the semiconductor device is particularly strongly dependent on the temperature. For example, if the discharge resistance RM is selected to be about 10? In the embodiment of Fig. 10, the change in resistance of the ignition fill is about 100 m? Or less (this is very important in determining the function of the output stage) It can hardly be distinguished from the change caused. The solution to this problem is achieved as follows by the present invention. That is, in the embodiment of FIG. 10, a bridge circuit is formed, and in addition to the first switch elements T11, T12, T13 and T14 including the ignition coil ZP1 and the capacitor CZK1, , The switch element TM1 is provided in the embodiment of FIG. 10, which has a significantly large conduction resistance value in the switched-on state. Advantageously, the transfer resistance of the second switch element TM1 is in a conduction state, Is set to be 10 to several hundred times the transfer resistance of the first switch element (T11, T12, ... T14). This is achieved by the following integration technique in the manufacture of semiconductor switch elements. That is, a very small chip area is allocated to the second switch element TM1. For example, the chip area of the second switch element is selected to be 1/10 to 1/100 of the chip area of the first switch element. As a result, a particularly large transfer resistance can be obtained in the conduction state in the second switch element. The block circuit diagram of Fig. 10 also shows a current source denoted IQ1. This current source is connected in series to the switch element TM1. If the first and second switching elements are advantageously fabricated with integrated technology, as described above, this current source IQ1 can also be suitably manufactured by an integration technique. As a simplest example, this kind of current source is realized, for example, as a voltage divider, which is connected between the positive terminal of the supply voltage and the ground terminal. This current source IQ1 sends out, for example, the first current 19. This current is between about 10 mA and about 100 mA. The inspection of the output stage shown in Fig. 10 using the second switch element TM1 will be described in detail with reference to the timing chart shown in Fig. Here, Fig. 13A shows the conduction state of each switch element TM1. 13B shows the operation state of the current source IQ1, and the curve in Fig. 13C shows the voltage transition as a function of time with respect to the transfer resistance of the switch element TM1. In Fig. 13A, it has been found that the switch element TM1 is blocked at time intervals 0 to t1, and then is controlled to be in the conduction state. The current source IQ1 is also cut off at the time interval of 0 to t1, and the current IQ1 is transmitted at the time t1. The closing connection of the current source IQ1 and the control of the switching element TM1 are advantageously performed by the control device 201 (see Fig. 9). The control terminal M1 of the switch element TM1 is connected to the control device 201 for this purpose. 13C shows the voltage drop UZKP1. This voltage drop is caused by the current IQ1 sent out from the current source IQ in the input connection state with respect to the transfer resistance of the switching element TM1. This voltage drop is a product of the latter current and the value of the transfer resistance . This voltage drop UZKP1 is likewise advantageously detected by the control device 201 and used for subsequent calculations. Here, as is well known, a voltage drop applied as an analog voltage value is converted into a digital value by an A / D converter, and this digital value is used for subsequent processing. With the measured voltage drop UZKP1 and the current IQ1 of the current source IQ already known, the control device 201 detects the transfer resistance of the switching element TM1 applied to the measuring point in consideration of the Ohm's law . However, if the transfer resistance value of the switching element TM1 is obtained by calculation taking into account the measurement of the voltage drop (UZKP1) and the current IQ1 of the current source IQ and the continuing Ohm's law, (T11, T12, T13, T14) are also obtained. This is because the resistance value of these is proportional to the transfer resistance value of the switch element TM1 based on the area ratio of the chip area. Next, if the transfer resistances of the switch elements T11, T12, T13 and T14 are sufficiently known, the value of the ignition charge resistance can be always obtained with high accuracy by using the inspection current flowing through the ignition charge ZP1, Therefore, the function capability of the ignition fill ZP1 can be estimated. Considering the inevitable tolerances on the inspection current and the measurement scale factor and also considering the chip area ratio between the first switch element and the second switch element, the tolerance area for obtaining the instantaneous resistance value of the ignition fill ZP1 is derived do. This tolerance range is on the order of 10 mΩ. If the resistance value of the ignition coil ZP1 can be detected with sufficiently high accuracy, this relatively small deviation is expected. Therefore, errors that occur can be detected in a timely and reliable manner. An equivalent advantage is also obtained in the embodiment of the simple output stage shown in Figs. 11 and 12. Fig. 10, 11, and 12, only one output terminal having one ignition charge ZP1 is shown. Of course, as shown in FIG. 9, it is also possible to provide a plurality of output terminals of the same type, and it is also possible to add the second switch element TM1 and the associated current source IQ to the output terminals thereof, respectively. If all of the output stages 30/1, 30/6 are integrated in only one switching device, it is of course possible to commonly connect the same second switching device TM1 and only one current source IQ ).

In the following embodiments, for example, it is possible to detect and consider the transfer resistance of a switch element manufactured by an integrated technique. Here, the reference path is additionally provided, and unlike the embodiment described above, a special current source can be omitted. In the embodiment of Fig. 14, two push / pull output stages constituted by a bridge circuit are provided for the control of the respective ignition circuits C1, R1 to C3 and R3. C1 and C3 are also capacitors here and are connected in series with the ignition fill indicated by resistors R1 and R3. The switch elements S1, S2, S3, S4 and S9 of the first output stage and the switch elements S5, S6, S7, S8 and S10 of the second output stage are advantageously switch elements manufactured by integration technology, For, it is a MOS transistor. Between the output terminals, a reference path made up of a series circuit of the capacitor C2 and the resistor R2 is connected. UB represents the battery voltage. The resistance measurement can be performed as follows. The switch element S4 is first closed and the battery element voltage UB is applied to the series circuit of the ignition circuits C1 and R1 by closing the switch element S9 to charge the capacitor C1. The capacitance value of the capacitor C1 is detected from the charge curve. The capacitor C1 is discharged through the resistor R1 of the ignition circuit by closing the switch elements S2 and S4 for a predetermined time t for a short time. The voltage that also occurs in the capacitor C1 is a measure of the value of the resistor R1. In this case, correction must be performed depending on the measurement procedure described above. As the resistance measurement, the transfer resistance of the switch elements S2 and S4 was accepted as an amount of an impediment. This potential resistance is affected by the sampling error and is usually strongly dependent on the temperature. Therefore, in the second measurement step described above, the resistance value of the sum of the resistance value of the resistor R1 and twice the transfer resistance (the switch elements S2 and S4) is measured instead of the resistance value of the resistor R1. A comparative measurement is performed on a reference route made up of the capacitor C2 and the resistor R2 so as to be detectable for correcting the transfer resistance. C2 and R2 is connected between two push / pull output terminals. These two output terminals control one ignition circuit (C1, R1 to C3, R32), respectively. This push / pull output stage can be constituted as a whole bridge as shown in Fig. 14, or as a 3/4 bridge by omitting the switch elements S3 and S7. With this arrangement of the reference paths (C2, R2), the measurement of the reference resistance to this reference becomes possible without additional additional elements. The measurement of the resistance in the reference path is practically performed in the same manner as the measurement described above. Therefore, first, the capacitor C2 as the reference capacitor is charged by closing the switch elements S8 and S9. On the other side, the capacitor C2 is at least partially discharged by closing of the switch elements S2 and S8. As described above, the resistance value of the reference line can be detected from this discharging process. However, the measurement result is the sum of the reference resistance R2 and the transfer resistances of the switch elements S2 and S8. However, since the resistance of the reference resistor R2 as a reference is already known, the transfer resistance of the switch elements S2 and S8 in a closed state can be calculated. Next, by using the already known transfer resistances, it is possible to correct the resistance value of the resistors R1 (R3) of the ignition circuit obtained in the above-described measuring process.

In the case where the switch elements S1 and S8 are integrated by an integration technique, the gap between the transfer resistances of these switch elements is very small. This is because the variation of the parameters in the same integrated circuit is very small and all switch elements have substantially the same operating temperature. Therefore, the influence of the transfer resistance of the switch element on the resistance value of the ignition circuit can be almost completely corrected by the reference measurement. When the output stage circuit is driven by not only two output stages but also a plurality of, for example, four, entire bridge circuits, as shown in Fig. 14, in order to perform the necessary correction, only one reference It will only be necessary.

The switch element S1 can be operated simultaneously with the switch element S7 and the switch element S2 so that the energy does not disappear in the reference paths C2 and R2 even when the ignition circuits C1 and R1 to C3R3 are simultaneously controlled. Is clock-controlled simultaneously with the switch element S8. The switch elements of the second ignition circuits C3 and R3 are not closed when it is necessary to trigger one ignition circuit, for example, the ignition circuits C1 and R1.

Fig. 15 shows a modified embodiment of Fig. In this embodiment, the terminal on the opposite side of the capacitor C2 of the reference-side resistor R2 is connected to the terminal on the opposite side of the capacitor C3 of the resistor R3 of the ignition circuit. In this configuration, the measurement steps already described with reference to Fig. 14 are applied correspondingly. However, the switching element S6 is controlled in the case of measuring the ignition circuit instead of the switching element S8, and the switching element S1 is synchronized with the switching element S5 and the switching element S2 is switched to the switching element S6 during the ignition, Respectively.

Another specific embodiment of the circuit configuration is shown in Fig. The city here is limited to the entire bridge circuit only. One of these full bridge circuits at the output stage of the integrated technology additionally has a separate switch element S5. This switch element S5 is likewise an output transistor composed of MOS technology and has substantially the same structure as the switch elements S2 to S4. The reference element C2 having the capacitor C2 and the resistor R2 Is connected between each terminal of the switch element S5 and the switch element S2 in this case. The output terminal shown in Fig. 16 should be configured as a 3/4 bridge, and the switch element S3 may be omitted.

Claims (19)

An electronic safety device for a passenger in a vehicle, comprising an acceleration sensor and at least one inertia prevention device, A control device connected to the acceleration sensor, the control device comprising at least one microcomputer, At least one output end for controlling the at least one inertia prevention device and connected to the control device, the at least one output end including ignition fills (squib) Wherein at least one error condition and at least one associated control indication of the electronic safety device is stored in the memory device, and wherein the at least one inertia prevention device is operable to detect at least one of the at least one Is activated in accordance with the at least one control instruction when an error condition of the electronic safety device occurs. 2. The electronic safety device according to claim 1, wherein a supply voltage is applied to the safety device and the control indication is determined as a function of the supply voltage. 3. The method of claim 2, wherein the at least one output end comprises at least one first switch element, When the supply voltage is in the range of 30V to 45V and a short circuit condition exists between the ignition fill and the positive pole of the supply voltage, the at least one first switch element is a function of the clock- Wherein the at least one first switch element is in a conducting state during a first time interval and is in a blocking state during a second time interval. 4. The vehicle passenger electronic safety device of claim 3, wherein the at least one output stage further comprises at least two second switch elements, and the at least two second switch elements during the second time interval are in the conductive state, . 5. The electronic safety device according to claim 4, wherein the at least one first switch element and the at least two second switch elements comprise semiconductor elements. 4. The electronic safety device of claim 3, wherein the first time interval has the same duration as the second time interval. 4. The electronic safety device for a passenger of a vehicle according to claim 3, wherein the first time interval has a duration in the range of 5 mu s to 10 mu s. 8. The electronic safety device for a passenger of a vehicle according to claim 7, wherein the duration is 7 占 퐏. 4. The apparatus of claim 3, wherein the at least one output stage further comprises at least two third switch elements, wherein during the first and second time intervals, the at least two third switch elements < An electronic safety device for a vehicle passenger in one of the states. 3. The method of claim 2, wherein the at least one output stage comprises at least one first switch element and at least two second switch elements, When the supply voltage is in the range of 24V to 30V and a short circuit is present between the ignition fill and one of the anode and ground connections of the supply voltage, the at least one first switch element is a function of the clock- Wherein the at least one first switch element is in a conducting state during a first time interval and is in a blocking state during a second time interval, And the two second switch elements are in the conductive state. 11. The electronic safety device of claim 10, wherein the first and second time intervals have a duration in the range of 3 mu s to 10 mu s. 11. The electronic safety device of claim 10, wherein the first and second time intervals have a duration of 5 占 퐏. 3. The method of claim 2, wherein the at least one output stage includes at least two first switch elements, at least two second switch elements, and at least two third switch elements, Wherein the supply voltage is in the range of 9V to 24V and a short circuit is present between the ignition fill and the anode of the supply voltage, The two third switch elements can be selectively triggered in a push-pull operation as a function of the clock-pulse timing signal, and the at least two first switch elements, the at least two second switch elements And the first subset of the at least two third switch elements are in a conductive state for a first time interval and the at least two first switch elements, the at least two second switch elements and the at least two The second subset of third switch elements is in a blocking state during the first time interval, the first subset is in a conductive state during a second time interval, And the second subset is in a blocking state during the second time interval. 14. The electronic safety device of claim 13, wherein the first and second time intervals have durations in the range of 2 [mu] s to 8 [mu] s. 14. The electronic safety device of claim 13, wherein the first and second time intervals have a duration of 3 占 퐏. 3. The apparatus of claim 2, wherein the at least one output stage comprises at least one first switch element, at least two second switch elements and a capacitor connected in series to the ignition fill, When the supply voltage is in the range of 30V to 45V and a short circuit is present between the terminal of the capacitor and one of the positive and ground connections of the supply voltage the at least one first switch element is a function of the clock- Wherein the at least one first switch element is in a conducting state during a first time interval and is in a blocking state during a second time interval, And is in the blocking state and in the conduction state during the second time interval. An electronic safety device for a passenger in a vehicle, comprising an acceleration sensor and at least one inertia prevention device, A control device connected to the acceleration sensor, the control device comprising at least one microcomputer, At least one output terminal connected to said control device for controlling said at least one inertia prevention device, comprising a plurality of first switch elements and a plurality of second switch elements, said plurality of first and second switch elements Wherein each of the plurality of first and second switch elements is one of an on state and an off state and is formed using an integrated circuit technique, Wherein the transfer resistor has at least one output end which is greater than the first transfer resistance of each of the plurality of first switch elements. 18. The method of claim 17, wherein when one of the plurality of second switch elements is in the ON state, the second transfer resistance of the second switch element is greater than the second Wherein the first transmission resistance of one of the first switching elements is greater than the first transmission resistance of one of the first switching elements. 18. The method of claim 17, further comprising: determining a reference branch to determine one of the plurality of first switch elements, the first transfer resistor being one of the plurality of first switch elements and the second transfer resistor being one of the plurality of second switch elements. ) Circuit, wherein the reference circuit comprises a capacitor in series with the resistor, the capacitor being capable of charging or discharging as a function of the state of at least one of the plurality of first and second switch elements Electronic safety devices for passenger cars.

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