JPH0723672U - Occupant protection system actuator - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a compact occupant protection system actuator. A power unit 3 for activating an occupant protection system that protects an occupant from an impact caused by a vehicle collision by electric energy when the activation signals S1 to S4 are input, and a power supply unit 4 for supplying electric energy to the power unit 3. , An acceleration sensor GS for detecting a collision of the vehicle, and a collision based on an input from the acceleration sensor GS to determine a collision, and a start signal S1 to the power unit 3
In the actuating device 41 including the electric circuit 2 having the signal processing unit 5 that outputs S4, 1 or 2 which is created by matching at least a part of the electric circuit 2 with the circuit of the unit.
It is configured by using the dedicated ICs 42, 43, 45 described above.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an actuator for an occupant protection system in the event of a vehicle collision, and more particularly to one that achieves size reduction, weight reduction, and cost reduction.

[0002]

[Prior art]

 FIG. 3 shows a conventional example of an actuating device for an occupant protection system of this type. FIG. 3 is a functional block diagram showing a schematic configuration of a conventional occupant protection system. First, the configuration will be described. In FIG. 3, the operating device 1 of the occupant protection system includes an electric circuit 2 having a power unit 3, a power supply unit 4, a signal processing unit 5, and an acceleration sensor GS. The power unit 3 is supplied with electric energy and squibs Q1 to Q4 for igniting and activating an occupant protection system (not shown), and switch circuits (switch means) 7 to 10 for receiving and transmitting activation signals S1 to S4, Four circuits in which the power resistors 11 to 14 are connected in series are connected in parallel, and the four parallel circuits and the safing sensor SS are connected in series to the power supply unit 4. Q1, Q2, Q3, and Q4 are squibs of a driver airbag, a passenger airbag, a driver pretensioner, and a passenger pretensioner, respectively. The switch circuits 7 to 10 are composed of transistors or the like. The safing sensor SS is a normally-open collision sensor that closes (conducts) the contacts so that it can recover at a predetermined acceleration smaller than that of the switch circuits 7 to 10, and prevents accidental explosion. The power resistors 11 to 14 limit the circuit current when the squibs Q1 to Q4 are energized, and flow current to other squibs even if one of the squibs Q1 to Q4 is short-circuited.

A drive circuit 15 for the warning lamp WL is provided in the power unit 3. The warning lamp WL is installed in the vehicle and warns the operator if there is a failure as a result of the diagnosis of the electric circuit 2 of the occupant protection system. A diagnostic resistor 32 is connected in parallel with the safing sensor SS, and diagnostic resistors R1 to R4 and R5 to R8 are connected in parallel with the switch circuits 7 to 10. The squibs Q1 to Q4 and the warning lamp WL are connected to each circuit using connector pins 16 to 23 and 24, respectively.

The power supply unit 4 boosts a voltage supplied from an on-vehicle battery (not shown) using an inductor L, and a backup capacitor that is charged by the output of the booster circuit 26 and supplies electric energy to the power unit 3. C1 to C3, a 5V constant voltage circuit 28 that supplies a 5V constant voltage to the signal processing unit 5, the diagnostic circuit 31 and the like, and an input voltage supplied to the 5V constant voltage circuit 28 from either the vehicle battery or the booster circuit 26. And a voltage switching circuit 27 for switching to the other one. The power supply unit 4 is connected to the vehicle-mounted battery via the connector pin 25.

The signal processing unit 5 determines a collision based on the input from the acceleration sensor GS and outputs a start signal S1 to S4 to the switch circuits 7 to 10, and a predetermined circuit of the electric circuit 2. The diagnostic circuit 31 is connected to the location and the warning lamp drive circuit 15 and diagnoses whether or not the circuit 2 is disconnected.

The electric circuit 2 is composed of many electronic parts (not shown). Among them, the signal processing unit 5 includes a CPU and has a high degree of integration, but the other power unit 3 and the power supply unit 4 use a lot of discrete components and thus have a low degree of integration.

Next, the operation of the operating device 1 will be described. That is, at the time of a collision, when the collision determination circuit 30 determines that the collision occurs based on the input signal from the acceleration sensor GS, the start signals S1 to S4 are output, the switch circuits 7 to 10 are conducted, and the safing sensor is activated. The SS also detects the collision and closes the contact. As a result, the electric energy stored in the backup capacitors C1 to C3 is supplied to the squibs Q1 to Q4, and the energizing heating of the squibs Q1 to Q4 ignites an ignition charge (not shown) to activate the air bag and the pretensioner. .

Further, at normal times, a weak current flows through the signal line 36, the diagnostic resistors 32, R1 to R4, and R5 to R8, and the diagnostic circuit 31 receives the voltage signals V1 to V9 at predetermined locations of the electric circuit 2. It is input and checked for disconnection, short circuit, etc. Then, if there is an abnormality, a warning signal is output from the diagnosis circuit 31 to the warning lamp drive circuit 15, and the warning lamp WL is turned on.

[0009]

[Problems to be solved by the device]

 By the way, the actuating device of the occupant protection system described above is required to be compact and lightweight because it is installed in a limited space in an automobile. In particular, the occupant protection system has traditionally considered only the installation of airbags for the driver's seat.However, consideration has also been given to the installation of airbags for the passenger seat and, as mentioned above, pretensioners for the driver's seat and passenger seat. As a result, the size of the actuating device has increased, and there is a demand for even smaller size and lighter weight. At the same time, the number of functions required for the actuators increased, and the number of parts inevitably increased, which was a factor of cost increase.However, from the perspective of protecting passengers, a significant cost reduction was required to popularize air bags and pretensioners. Down is requested.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a small, lightweight, and inexpensive occupant protection system operating device. To do.

[0011]

[Means for Solving the Problems]

 In order to solve the above problems, an activating device for an occupant protection system according to the present invention includes a power unit for activating an occupant protection system that protects an occupant from an impact caused by a vehicle collision by electric energy when an activation signal is input; A power supply unit that supplies electric energy to the unit, an acceleration sensor that detects a collision of the vehicle, and a signal processing unit that determines a collision based on an input from the acceleration sensor and outputs a start signal to the power unit. In an operating device provided with an electric circuit, at least a part of the electric circuit is configured by using one or more dedicated ICs created in accordance with the circuit of the part.

[0012]

[Action]

 Since at least a part of the electric circuit of the actuating device is configured by using a dedicated IC (semi-custom IC or full-custom IC) created in conformity with the circuit, it can be integrated into an IC in accordance with the circuit. Therefore, the degree of circuit integration can be further increased, the size and weight of the circuit can be reduced, and mass production can be achieved, resulting in a significant cost reduction.

[0013]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram of an operating device of an occupant protection system of the present invention, and FIG. 2 is a component layout diagram. 1 and 2, parts having the same functions as those in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted.

1 is different from FIG. 3 in that a part of the power unit 3 and the power supply unit 4 of the electric circuit 2 of the actuating device 41 and almost the entire signal processing unit 5 are arranged in accordance with the circuit. It is configured using the power ASIC 43, the power supply ASIC 42, and the signal processing ASIC 45, which are the created dedicated ICs, respectively, and each connector pin 16 to 25 of the squib, the in-vehicle battery, and the warning lamp WL is one connector (first and second. 2nd connector) 29. The ASIC is a custom IC, and either a semi-custom IC or a full custom IC may be used. Compared to the case of using a general-purpose IC, the use of a custom IC makes it possible to create an IC that is just enough according to its application (circuit), and can be made smaller and lighter.

In the power unit 3, the connector 29 and the safing sensor SS are not included in the power ASI C45 because of the structure, the power resistors 11 to 14 are difficult to be ASIC due to heat generation. Further, the diagnostic resistors R1 to R8 and R32 need not be included in the power ASIC 45 because they need to be matched to specifications such as a squib and do not require a large mounting area. However, most of the other components including those not shown are included in the power ASIC 45. The switch circuits 7 to 10 can have a current limiting function in addition to the switch function. In this case, the power resistors 11 to 14 are unnecessary.

The power supply unit 4 is not included in the power supply ASIC 42 because the backup capacitors C1 to C3, the inductor L, a decap (not shown), and the like are difficult to be formed into an ASIC because of their capacity. However, most of the other parts, including parts not shown, are included in the power ASIC 42.

The signal processing unit 5 is almost entirely included in the signal processing ASI C45 except for a bypass capacitor (not shown) and the like.

The acceleration sensor GS requires circuits for temperature compensation, characteristic compensation, amplification, etc., but in the present embodiment, those including these are used. When using an acceleration sensor having these as separate circuits, the separate circuit portion can be formed into an ASIC.

In this way, by maximizing the ASICs of the respective parts 3 to 5 of the electric circuit 2, the maximum merit of downsizing can be obtained. For example, the conventional actuating device in FIG. 3 has a lunch box size of 150 mm length × 120 mm width × 60 mm height, but in the present embodiment, it has a length of 90 mm × 60 mm width × 30 mm height and a business card box size. The size was dramatically reduced to about 1/3 in flat area, about 1/7 in volume, and about 1/4 in weight, and the cost could be reduced to about 1/4. Further, due to the difference in the functions of the respective units 3 to 5 of the electric circuit 2, the ASIC range and the degree of integration are different at the present time. Therefore, as in this embodiment, it is advantageous to make each part an ASIC and increase the degree of integration as much as possible within that range in order to increase the overall degree of integration.

Next, the component arrangement will be described with reference to FIG. In FIG. 2, on a rectangular printed wiring board 32, a connector 29 is arranged on one of the two opposite sides (right side in the drawing) and a safing sensor SS is arranged on the other side (right side in the drawing) along each side. At the same time, the acceleration sensor GS is arranged on one of the other two opposite sides (the lower side in the drawing), and the backup capacitors C1 to C3 are arranged on the other side (the upper side in the drawing) along the respective sides. A power ASIC 43, a signal processing ASIC 45, and a power supply ASIC 42 are arranged in this order from the connector 29 to the safing sensor SS in the central space, and an inductor L is arranged near the power supply ASIC 42 (between the power supply ASIC 42 and the signal processing ASIC 45). Has been done.

The connector 29 needs to be arranged on the outside in order to attach / detach the counterpart connector, and the power ASIC 43, the signal processing ASIC 45, and the power supply ASIC 42 need to prevent damage. On the other hand, the connector 29, the acceleration sensor GS, the safing sensor SS, and the backup capacitors C1 to C3 have high strength. Therefore, as shown in the figure, by arranging the parts with high strength such as the connector 29 on the outside and the ASICs 42, 43, 45 on the inside, the ASICs 42, 43, 45 are secured while ensuring the function of the connector 29. It can be protected from damage in the assembly process. Further, the power supply ASIC 42 (having an oscillator in the booster circuit) and the safing sensor SS have high signal levels, while the signal processing ASIC 45 and the acceleration sensor GS have low signal levels. However, it is preferable to dispose them separately from each other, which can prevent noise. Further, it is rational to arrange the power ASIC 43 between the signal processing ASIC 45 and the connector 29 along the signal flow because the wiring distance can be shortened, and since the inductor L has a small strength, it can be connected to the power supply ASIC 42 and the signal. It is rational to arrange it between the processing A SIC 45 in order to prevent damage and save space.

[0022]

[Effect of device]

 As described above, the operating device of the occupant protection system of the present invention is an operating device including an electric circuit having a power section, a power source section, an acceleration sensor, and a signal processing section, and at least a part of the electric circuit is provided. Since it is configured by using a dedicated IC created according to the circuit of each part, it can be integrated into an IC that is appropriate for the circuit, and the degree of integration of the circuit can be increased, and the size and weight can be reduced accordingly. It is possible. Also, at the same time, the number of parts can be reduced and mass production can be performed, which can significantly reduce the cost and improve the reliability.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an operating device of an occupant protection system of the present invention.

FIG. 2 is a component layout view of an operating device of the passenger protection system of the present invention.

FIG. 3 is a functional block diagram of an actuating device of a conventional occupant protection system.

[Explanation of symbols]

 C1 backup capacitor C2 backup capacitor C3 backup capacitor GS acceleration sensor L inductor Q1 squib Q2 squib Q3 squib Q4 squib S1 start signal S2 start signal S3 start signal S4 start signal SS safing sensor 2 electric circuit 3 power section 4 power section 5 signal processing Part 7 switch circuit (switch means) 8 switch circuit (switch means) 9 switch circuit (switch means) 10 switch circuit (switch means) 26 booster circuit 29 connector (first and second connector) 30 collision determination circuit 31 diagnostic circuit 32 Printed wiring board (wiring board) 41 Actuator 42 Power supply ASIC (dedicated IC) 43 Power ASIC (dedicated IC) 45 Signal processing ASIC (dedicated IC)

Claims (12)

[Scope of utility model registration request] 1. A power unit for activating an occupant protection system that protects an occupant from an impact due to a vehicle collision by electric energy when a start signal is input, a power supply unit for supplying electric energy to the power unit, and a vehicle collision. An acceleration sensor that detects a collision, and a signal processing unit that determines a collision based on an input from the acceleration sensor and outputs a start signal to the power unit. An operating device for an occupant protection system, characterized in that the section is configured by using one or more dedicated ICs created according to the circuit of the section. 2. A power unit for activating an occupant protection system that protects an occupant from an impact caused by a vehicle collision by electric energy when a start signal is input, a power supply unit that supplies electric energy to the power unit, and a vehicle collision. An acceleration sensor for detecting a signal, and a signal processing unit that determines a collision based on an input from the acceleration sensor and outputs a start signal to the power unit, the power unit of the electric circuit. A combination of any one of the power supply section and the signal processing section, or a combination of any of the sections, at least a part of each section is configured by using a dedicated IC created according to the circuit of the section. Actuating device for occupant protection system. 3. The operating device for an occupant protection system according to claim 2, wherein any one of the parts is a power part. 4. The actuating device for an occupant protection system according to claim 2, wherein any one of the parts is a power supply part. 5. The occupant protection system actuating device according to claim 2, wherein any one of the units is a signal processing unit. 6. The operating device for an occupant protection system according to claim 2, wherein the combination of any one of the units is a power unit, a power supply unit, and a signal processing unit. 7. The power unit, and one or more parallel circuits which are connected in series with a squib which is supplied with electric energy to start ignition of the occupant protection system and a switch means which receives a start signal and conducts electricity. , A normally-open safing sensor that conducts in a recoverable manner at a predetermined acceleration smaller than the switch means is connected in series to the power supply section, and the portion configured by using the dedicated IC is a portion including at least the switch means. The occupant protection system actuating device according to claim 3 or 6, wherein: 8. The power supply unit includes a booster circuit that boosts a voltage supplied from a vehicle-mounted battery by using an inductor, and a backup capacitor that is charged by the output of the booster circuit and supplies electrical energy to the power unit. 7. The actuating device for an occupant protection system according to claim 4 or 6, wherein the portion configured by using the dedicated IC is a portion excluding at least the inductor and the backup capacitor. 9. The operating device for an occupant protection system according to claim 5, wherein the signal processing unit is configured almost entirely using the dedicated IC. 10. The signal processing unit diagnoses a collision determination circuit that determines a collision based on an input from an acceleration sensor and outputs a start signal to a power unit, and a weak current to the electric circuit to diagnose the presence or absence of disconnection. 7. An operating device for an occupant protection system according to claim 5 or 6, characterized in that it is provided with a diagnostic circuit for operating the occupant protection system. 11. An operating device for an occupant protection system that protects an occupant from a shock caused by a vehicle collision, comprising an electric circuit having a power section, a power supply section, a signal processing section, and an acceleration sensor, wherein the power section is , One or more parallel circuits in which a squib which is supplied with electric energy to start ignition of the occupant protection system and a switch means which receives a start signal and conducts are connected in series, and a predetermined acceleration smaller than the switch means. And a normally-open safing sensor which is conductive so as to be recoverable by means of a power supply unit connected in series to the power supply unit, and a portion including at least a switch means is constructed by using a dedicated power IC prepared in accordance with the circuit of the portion. The power supply unit boosts the voltage supplied from the vehicle-mounted battery by using an inductor, and the power supply unit is charged by the output of the booster circuit to charge the power supply. A backup capacitor for supplying electric energy to the power supply unit, and at least a portion excluding the inductor and the backup capacitor is configured by using a dedicated power supply IC created according to the circuit of the portion, and the signal processing unit is , A collision is determined based on an input from the acceleration sensor, a start signal is output to the power unit, and almost the entire unit is configured by using a dedicated signal processing IC created according to the circuit of the signal processing unit. A first connector that connects both ends of the battery to the electric circuit and a second connector that connects the vehicle-mounted battery to the booster circuit, and the first connector is provided on one of two opposing sides on a rectangular wiring board.
A second connector, the safing sensor on the other side along each side, the detection IC on one of the other two opposite sides, and the backup capacitor on the other side along each side. The power protection IC, the signal processing IC, and the power supply IC are arranged in a central space formed by these components. 12. The power IC, the signal processing IC,
The power supply IC is provided in the central space from the first and second connectors toward the safing sensor, the power IC, and the signal processing I.
12. The occupant protection system actuating device according to claim 11, wherein C and the power supply IC are arranged in this order, and the inductor is arranged in the vicinity of the power supply IC.