JPH03500348A - Compact collision detection switch with air channel and diagnostic system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 3. The ball and the tube are made of materials with different thermal expansion coefficients, and the front The recording tube has a coefficient of thermal expansion sufficiently larger than that of the ball, and has a thermal expansion coefficient that is large enough to withstand temperature. Global compensation for changes in viscosity is achieved by thermal expansion of the tube with respect to the ball. The invention according to claim 1.

4. The ball and the tube are made of materials with different thermal expansion coefficients, and the front The recording tube has a coefficient of thermal expansion sufficiently larger than that of the ball, and has a thermal expansion coefficient that is large enough to withstand temperature. The overall compensation of the viscosity change caused by the ball is achieved by thermal expansion of the tube with respect to the ball. The invention according to claim 2.

5. In a first collision occupant protection system adapted to detect a vehicle collision. The improvement incorporates resistance sensing means to determine if the resistance of said ignition circuit is within predetermined limits. an occupant protection system, the first crash sensor being adapted to determine whether the Mu.

6. The resistance sensing means detects substantially the entire voltage of the vehicle electrical system to the ignition circuit. and the ignition while the full voltage of the vehicle electrical system is applied. 6. The invention according to claim 5, characterized by a resistance of the circuit.

7. A claim including a second collision sensor connected in parallel with the first collision sensor. Invention according to item 5.

8. Changing the state of the ignition circuit by transmitting an electrical signal to the conductor of the ignition circuit. The invention as claimed in claim 5, comprising means adapted for communicating information regarding the status. .

9゜ The state of the ignition circuit is changed by transmitting an electrical signal to the conductor of the ignition circuit. The invention as claimed in claim 6, comprising means adapted for communicating information regarding the status. .

10. Said means adapted for communicating information include said firing circuit of said full voltage. 10. The method of claim 9, further comprising means for controlling the timing of said application to a path. invention of.

11. In a type of collision sensor that includes a movable ball in a sealed tube, the distance traveled means for pushing the ball into its normal rest position on one end of the and detecting means for detecting when the other end of the travel distance is approached, and the tube is viscous. filled with a viscous medium, with a gap between the ball and the tube to fill the viscous medium. a first for viscously transmitting the body from one side of the ball to the other side of the ball; The improvements include providing liquid conduit means; A crash sensor comprising resilient means adapted to support said crash sensor.

12. The elastic means is less elastic in the axial direction of the tube than in the vertical direction. The invention according to claim 11.

13. The elastic means includes an elastic material extending in the axial direction of the tube; The elastic material extends in a direction defined by two cylinders concentric with the axis. 12. The invention according to claim 11, existing in pace.

14. upon detecting a collision, the first collision is adapted to close the first switch; a collision detection means and a second switch adapted to close the second switch upon detecting a collision; In the type of occupant protection comprising a collision detection means, the first and second collision detection means Both switches must be closed to begin deploying the occupant protection system. The improvements are connected in series, so that connected in parallel with one of said switches and when voltage is applied for more than a short period of time. Occupant protection system comprising electrically resistive means adapted to stop conduction of electricity.

15. said short period is between 0.01 seconds and 1000 seconds in duration; The invention according to claim 14.

16. Electricity in a motor vehicle having an enclosure and wires entering said enclosure In the air device, the improvement is adapted for the path by which the wire enters the enclosure. said enclosure having a tubular element wrapped around said tubular element; , and a wrapper surrounding a length of the wire, the length of the wire being the length of the wire. external to the tubular element and adjacent one end of the tubular element; the wrapper is placed around the tubular element and on the length of the wire; a heat shrinkable tube lined with a meltable material that melts the meltable material; an electrical device that is heated sufficiently to cause the heat-shrinkable tube to shrink;

17° according to claim 16, comprising a filament parallel to the axis of the heat-shrinkable tube. invention of.

18. Claim 16, wherein the tube segment is crimped around the wire. The invention described in .

Specification Compact collision detection switch with air channel and diagnostic system This application was filed on July 14, 1988 and is filed on ``Air Channels and Diagnostic Systems''. U.S. Patent Application No. 2 entitled “Compact Collision Detection Switch with System” No. 18.917, a continuation-in-part application, filed on October 26, 1988, “ "Compact Collision Detection Switch with Air Channel and Diagnostic System" This is a continuation-in-part of U.S. Patent Application No. 262,732.

field of invention This invention closes when a car is in a head-on collision, and the airbag or belt tension This relates to a switch that activates occupant protection devices such as a vehicle. This invention is Additionally, a diagnostic system monitors the occupant protection system to ensure a proper ignition circuit. It is related to the system.

Background of the invention Airbags are inflatable airbags that are folded out of sight in case of a frontal collision. It's a bag. During a collision, materials containing sodium azide typically undergo a chemical reaction. by causing gaseous products, which cause the inflated bag to between the driver and the steering wheel, or between the front seat occupant and the dash board. is interposed between.

Belt tensioners tighten the car's seatbelt in the event of a collision. This is a device that restrains people more safely. Tensioner inflates the airbag by pressurized gas obtained from the chemical reaction of gas-generating materials such as those used for It has a small motor that is driven. In both cases, the conversion of the gas-generating material The chemical reaction is triggered by an electrically heated fuse. Collision sensor of this invention is a switch for controlling the power applied to the fuse.

In the United States, cars with electrically activated airbag inflation required by law to have diagnostic capabilities to alert drivers of ignition circuit failure. There is.

Collision sensors of the type to which this invention is applicable are manufactured on a commercial basis. that consists of a metal ball that can move freely in a soil pipe containing contacts; , when the ball moves to one end of the tube, it is bridged by that ball. baud Airflow around the tube causes a pressure difference. The pressure difference is proportional to the relative velocity of the ball to the tube. example, and induces a force in the opposite direction of its velocity. Pier given by permanent magnet Scar holds the ball in its normal resting position without touching the contact and closes the switch. The velocity change required to reduce the impact increases with the duration of the vibration of the collision. force is relative to speed By way of example, a collision sensor acts as an acceleration integrator, allowing a predetermined velocity When the change is reached, the ignition circuit is completed. Collision sensor performance over a wide range of temperatures The air gap between the ball and tube changes with temperature to maintain The tube and ball can be manufactured from separate special stainless steels with a coefficient of expansion of The change in air viscosity with respect to temperature is compensated for by is the axis of the tube: this allows it to move in a perpendicular plane, and the acceleration in the orthogonal axis Prevents transmission to the pipes.

This collision sensor is expensive to manufacture, and one of the reasons for that cost is the ball and This means that high precision is required for the tube. cost for certain applications Another reason it's expensive is that the tubes must be made from materials that are difficult to machine. That means no. Another reason for the high cost is that this design , when the ball moves over a distance of approximately one-quarter inch, electrical contact is made. due to the requirement that the ball must always maintain good electrical contact with its ball. Ru. Additionally, in known designs, the contacts may be welded or soldered. Connected by stages to drop-in wires and diagnostic resistors. Through these processes, the board Significant contamination occurs during manufacturing in the vicinity of pipes and pipes, and therefore cleanliness is essential. Additional components and processing steps are required to maintain separation. Also , the thin materials necessary for the contacts to obtain appropriate flexibility are difficult to handle and However, it has the disadvantage that it is difficult to connect to service lines made of heavier materials. moreover, Diagnostic resistors are high-quality resistors that are inexpensive and have relatively high accuracy. Must.

The performance of the second collision sensor depends on the airflow between the ball and the inside of the tube, and the ball variable depending on whether you move near the center or near the inner wall. ◎In the event of a collision, the aerodynamic force generated by the ventilating effect The ball is pushed towards the center of the tube, while the lateral acceleration pushes the ball towards the wall. Ru. When the ball moves near the wall, a crescent-shaped air channel forms between the ball and the tube. can be done. When the ball moves to the center of the tube, there is a ring between the ball and the tube. Air channels are created. The crescent-shaped opening has about half the width of the annular opening for airflow. Has resistance.

Therefore, the change in velocity required for the ball to bridge contact is essentially Varies depending on the path of the ball.

Other collision sensors of similar design include a pie-scar that holds the ball in its place. To provide this, a spring is typically used as one of the contacts. permanent magnetism Stone bias also seems desirable for its simplicity, but those two designs They can be used interchangeably.

Safety sensors are typically located on the firewall or elsewhere inside the vehicle. a second collision sensor located near the front of the vehicle] or more collision sensors; connected in series. This is not a sufficient basis for deploying occupant protection systems. If a sudden impact such as Geru.

Diagnostic systems typically include a diagnostic resistor that supplies a small amount of current to the ignition circuit during normal operation. resistor and means for monitoring its fractional current. current is supplied Absence indicates that the ignition circuit is open. This diagnostic system is It also detects small fluctuations in the resistance of the ignition circuit, such as may be caused by connector wear. It is desirable to release it. To achieve this, the circuit requires high precision, but , the current system does not fully fulfill this function.

A circuit for measuring resistance was developed by this inventor in ``Resistance Sensors and Switches''. 1 entitled Resistance 5ensor and 5w1tch) J No. 74,076, filed July 16, 987. Ru.

The armature movement is viscous damped by air viscosity, and the armature's normal Variations in air viscosity with temperature are compensated for by changing the resting position of A mechanical collision with the collision sensor latched in the closed position according to the inventor. Detection switch (Mec’hanical CrashSensing 5w1t ch With Latch-ing In The C1osed Po5i tf.

n) Co-pending U.S. Patent Application No. 166, filed March 9, 1988, entitled J. ．． No. 044.

Integrated electronic circuits are commonly used in switching power transistors to control substantial electrical power. determines when the transistor and its switching power transistor should be turned on. Both circuitry and circuitry are included on a single silicon chip.

This circuit includes a voltage comparator, a tamming device, and a may include circuitry.

Semiconductor devices, including integrated circuits, are generally made of materials such as gold or aluminum Attaching fine wires to pads on semiconductors formed for that purpose. and are connected to each other by. The reliability of the pads is improved by methods such as sonic welding. An area of semiconductor that is large enough to allow high mounting. semiconductor chip The pads on the chip and the connections between the pads and the circuitry are connected to the circuitry on the semiconductor chip. formed as part of the manufacturing process.

Completed semiconductor chips are typically made of metal, ceramic, plastic, or other materials. mounted on a base made of other suitable material. The base is generally a completed semiconductor Contains connector pins for connecting the body device to other equipment. pad on chip are typically connected to the connector pins by stitch bonding. electrically The finished device's sophisticated chips and wiring are protected by encapsulation.

Many encapsulation methods are known, some meeting the requirements of the semiconductor industry. It has been highly developed to meet the demands. One method is to convert the completed chip and wiring into small It is covered with a can and soldered to the base to form an airtight seal. . Another method is to place the completed chip and wiring in a mold and filled with uncured thermoset plastic and allowed to harden to form the desired capsule. It is to form a seal.

The circuit for driving the MO3FET power transistor is not described in the literature. It is. A review of such circuits is provided by Motorola Inc. Published by Motorola Inc. and copyrighted in 1986, Power MOSFET) Transistor data (POWERMOSFET TRANS ISTORDATA), 2nd edition, Chapter 6.

The main objective of this invention is to overcome some drawbacks of the prior art, for automobiles An object of the present invention is to provide a collision sensor and diagnostic system.

Summary of the invention The invention includes a viscous damped ball movable within a sealed tube; The reliable Provides a collision sensor that is tall, compact, lightweight, and economical to manufacture do. Balls and tubes are dimensioned to use the least amount of the most economical materials. Ru.

Further, according to the invention, the semiconductor switch controls power to the ignition circuit. minimizes the current that must be carried by the balls and contacts. Make it.

Furthermore, according to the invention, once the semiconductor switch is closed, the occupant protection system remains closed long enough to activate system deployment, thereby Contact dwell required in collision sensors that do not use semiconductor switches make it unnecessary.

Moreover, according to this invention, semiconductor switches are less expensive to manufacture. Controlled by a simple drive circuit.

Further, according to the present invention, the detection means is a well-known technique in the semiconductor manufacturing industry. A contact is a simple element that is attached to a pad on a semiconductor by include.

Furthermore, all the air displaced by the movement of the ball is trapped between the ball and the tube. According to one embodiment of the invention, the ball and tube are small and can be routed by plastic or aluminum, which greatly reduces cost compared to current designs. Tolerance and desired coefficient of thermal expansion are obtained to allow the use of large tubes. Ru.

Furthermore, according to a second embodiment of the invention, the air space displaced by the movement of the ball The air moves overwhelmingly through the axial channels on the outer surface of the tube within the cavity. child This makes the air flow faster than in collision sensors, where the air path is between the ball and the inside diameter of the tube. The variability of viscous resistance to airflow is reduced.

Furthermore, according to the aforementioned second embodiment of the invention, the size of the air channels is and maintains constant resistance to airflow at all operating temperatures.

Furthermore, according to a third embodiment of the invention, the air space displaced by the movement of the ball The air moves overwhelmingly through axial channels formed on the inner surface of the tube. baud traps the air in these channels. This creates a bowed air path. viscous resistance to airflow compared to impingement sensors between the tube and the inner surface of the tube. Denaturation is reduced.

Additionally, according to the invention, small balls and tubes are used with semiconductor switches. When used, the size of the entire system becomes similar to the size of the semiconductor device, This, combined with the fact that electrical components include semiconductors, has led to highly developed electrical connection technology and equipment as well as encapsulation technology and Enabling use of the device.

Furthermore, according to the invention, the switch lowers the resistance of the ignition circuit more than known systems. Sensefet transistors for much more accurate monitoring Incorporate into the resistance measurement circuit.

Further, according to the invention, a safety sensor is included, and the resistance thereof is included in the resistance monitored by the path.

Furthermore, according to the invention, the collision sensors can be connected in parallel. Oppositions connected in parallel The collision sensors each have independent housings to detect collisions at various locations on the vehicle. or may be placed in the same housing to increase package reliability.

Furthermore, according to a fourth embodiment of the invention, two semiconductors are used for controlling the ignition circuit. body switches are connected in series. The second semiconductor switch connected in series is Preventing semiconductor failures that could inadvertently trigger the deployment of protection systems.

Furthermore, according to the invention, the two wires to the crash sensor complete the ignition circuit; It also supplies power to operate the semiconductor logic, and also provides protection against failures in the ignition circuit. used to convey information. This reduces the cost and complexity of vehicle wiring. is minimized.

Further, according to the invention, the collision sensor is isolated from vibrations perpendicular to its axis. This makes the sensor insensitive to vibrations in the orthogonal axes.

A thorough understanding of the invention will be provided by the following description, which refers to the accompanying drawings. cormorant.

Air damped collision sensor theory The movement of air through the orifice is streamlined or turbulent. Known air damping force In a protrusion sensor, the orifice is the gap between the ball and the tube. collision sensor For the flow to function as a viscous integrator, the flow must be a streamline flow, but this This would occur in a ball-and-tube collision sensor of practical size. is known. The viscosity of the air flowing through the gap between the ball and the tube changes with temperature. To increase. For collision sensors exposed to the external environment, the The overall viscosity variation is approximately 25%.

If the orifice size does not change with temperature, at extreme values of temperature This viscosity variation causes the 25% difference in viscosity change required to activate the sensor.

In the above-mentioned known equilibrium sensor, a lower expansion than the tube is used to compensate for temperature fluctuations. Since the ball is made of a material with a tensile modulus, the orifice size will vary depending on the temperature. It becomes larger when the degree is 1i.

In known collision sensors, when changing the size of the ball and tube, temperature changes Let us consider the consequences for the performance of the collision sensor, ignoring the effects of

For each ball size, block the air gap and contact between the ball and the tube. The distance traveled for the ridge must be specified. Regarding these three variables There may be many possible combinations, or some interrelationships may lead to the very simple combinations described below. A pure analysis is obtained.

We have a ball with a range of sizes, and the distance it travels is inversely proportional to the size of the ball. However, the air gap between the ball and the tube is constant and does not depend on the size of the ball. Consider a known collision sensor. The mass of the ball, and therefore in the event of a crash The force that moves the ball is proportional to the cube of the ball's diameter. Given and constant void and The mass flow rate of gas moving from one side of the ball to the other for a given pressure difference is It is not affected by the size of the ball. For example, for a small ball, the circumference of the air gap The decrease in mass flow rate caused by the decrease in the axial size of the air gap The increased quality per unit length of the void due to the reduced viscous force The amount is compensated by the flow rate. For a given acceleration, the pressure difference is is proportional to. A linear relationship between pressure and mass flow, and a bow of various magnitudes. 8 It is said that the flow ffi is constant for a constant pressure difference and a gap with respect to the hole. Therefore, for a given acceleration, the fit flow rate is proportional to the first power of the ball diameter. I can say that. Is it the fact that the area a ball passes through is proportional to the square of its diameter? , and for a given acceleration, the mass flow of gas] is proportional to the first power of the diameter of the ball. From the reasoning given above, it follows that, as is the case in most cases, the air is For a given acceleration, the ball in the tube is The viscosity of is inversely proportional to the diameter of the ball. Travel distance or ball size It is inversely proportional to the size of the ball, and the gap between the ball and the tube is constant and depends on the size of the ball. In the limited cases currently under consideration where the collision sensor is not It has been explained above that the positive or viscous change is not affected by the diameter of the ball. Ta.

Previous analyzes assumed a single temperature. Various sizes of balls under consideration From the above explanation, it can be seen that the ball diameter and travel distance are independent of the ball diameter. To compensate for the temperature, the width of the air gap must change with temperature, independent of the ball diameter. This means that it has to be transformed. To do this, the ball and tube must be The difference in coefficient of thermal expansion must be inversely proportional to the diameter of the ball.

Extrapolating the conclusion of the above explanation, given the ball and tube materials, and the above considered In the given case, there is a certain size of ball that provides the best temperature compensation. This means that

The above discussion was limited to the case where the distance traveled is inversely proportional to the diameter of the ball. this The limits are not realistic and, if done properly, would limit the different distances the ball travels. It would be desirable to expand this discussion to take into account. However, in that case analysis requires numerical integration, which results in specific results for the parameters under consideration. Ru. However, by examining the integrals that must be solved for each situation, gives the following convenient approximation at constant flow rate: In other words, the pressure difference is It changes as the -2.5th power of the width.

Due to the nature of streamline flow, a linear relationship exists between pressure difference and flow rate. Ru. Therefore, at a constant pressure difference, the flow rate changes as the 2.5th power of the gap width. do.

The above analysis shows that it is possible to reduce the size of currently manufactured collision sensors by a factor of 10. Applicable to The collision sensors currently manufactured are 2/2 inch in diameter. a somewhat smaller ball and a somewhat larger than one thousandth of an inch between the ball and the tube. It has an annular gap and about a tenth of an inch of travel within the tube. As a first step , according to the above analysis, the diameter of the ball is reduced by a factor of 10, i.e. about 0. It can be scaled down to 40 inches and the travel distance is only a factor of 10, or about 1 It can be expanded up to inches without changing the air gap. Applying the 2,5th power rule to reduce travel distance Applying this and noting that the 2°5 route of 10 is approximately 2.5, we can calculate the distance traveled from the beginning. This is the value of To return to 1 inch, make the air gap slightly larger than 0.01 inch. Based on the dimensions, it is necessary to reduce the size to slightly larger than 0004 inches. It turns out.

(Margin below) For collision sensors of known design, to compensate for changes in air viscosity due to temperature. The basics are discussed next. Ball and tube temperature of 2.5 10-8 degrees Fahrenheit The difference in expansion coefficients provides the required compensation in current crash sensors as described above. . When the diameter of the ball decreases by a factor of 10, the differential thermal expansion coefficient decreases by 1 to 25·10-8. Increase by 0 times. Reduce the air gap by a factor of 2.5 and reduce the travel distance by a factor of 2.5. When decreasing to a value of Fahrenheit, the differential decreases by 2.5 and thereby Each degree has a value of 0.10-8. This is the temperature of the ball close to 6.10-6. Added to the coefficient of expansion, the coefficient of thermal expansion of the tube becomes 16·10-6. This is a thermosetting values that can be achieved with plastics that are flexible and can be extruded, cast and injection molded. range, and of plastic tube and stainless steel bowl for temperature compensation. Bringing the fact that use is viable. In addition, the diameter of the ball or tube The air gap between the ball and the tube, expressed as a fraction of Therefore, current collision sensors that can be manufactured to the required tolerances In comparison, it is larger by a factor of 4. However, the diameter of the tube varies from device to device. and may need to match the ball to the actual diameter of the tube. unknown.

The above analysis is repeated for reducing the size of the current crash sensor by a factor of 6. It can be done. In the first step, the diameter of the ball is reduced by a factor of 6 to approximately 0.07 3 inches, and the distance traveled is a factor of 6 with no change in the air gap. It increases by about 0. It will be 6 inches. Use the 2.5 width law to reduce travel distance Considering that the 2.5 root of 6 is approximately 2,0, it is To return the travel distance to its initial value of 0.1 inch, change the air gap from 0°001 inch. From a value slightly larger to a value slightly larger than 0.0005 inch. results in the need to decrease.

If the ball and tube must provide compensation for all changes in air viscosity due to temperature, If so, the required coefficient of thermal expansion is calculated as follows. 1 degree Fahrenheit The difference in thermal expansion coefficient between the ball and the tube of 2°5.10-8 Provides the required compensation in the shock sensor. If the diameter of the ball is reduced by a factor of 6, the differential The coefficient of thermal expansion increases six times to become Yu5 and YuQ-8. 2. It's a factor of 0. If we reduce the travel distance to the value of the current collision sensor, it will be 2.0. The differential is reduced and thereby reaches a value of 7.5.10-6 per degree Fahrenheit.

Adding this to the temperature expansion coefficient of the ball, which is close to 6.1O-6, we get the temperature expansion coefficient of the tube. becomes 13.5・10-8. This value is approximately equal to the coefficient of thermal expansion of aluminum. aluminum tube and stainless steel ball for temperature compensation It means that something is doable.

Furthermore, the distance between the ball and the tube is represented by a fraction of the diameter of the ball or tube. The void can be balled or die-cast with drilling and reaming rods. The tube can be trained to the required length by one of several inexpensive processes, such as Compared to current crash sensors that can actually be manufactured in Lance, 3 is larger by a factor of

Again, it should be expected that the tube diameter will vary from device to device, and It may be necessary to match the ball to the actual diameter of the tube.

The above analysis is necessarily approximate. The ball is on the axis of the tube during the collision Do not move. In fact, it is more likely to occur on the walls of the tube at any given time. water. Also, the coefficient of thermal expansion of the ball and tube is 2.5·10-8 per degree Fahrenheit. The difference is not the best value to provide the required compensation in the current crash sensors mentioned above. Maybe not. For this and other reasons, the above analysis It should be considered as a general guide to outline the development of this document. collision sensor The final determination of the parameters for the Test by using Neeta model or until desired performance is achieved. This must be done by repeating.

Only one path for the air to be displaced as the ball moves is between the ball and the tube. The only compensation for the change in air viscosity due to temperature and through the air gap between This is done by selecting the coefficient of thermal expansion of the materials used for the balls and tubes. The above-mentioned analysis has mostly been applied to analyzing such crash sensors.

A collision sensor with the same ball size and travel distance is used for the viscous flow of air. Consider a collision sensor of the type previously discussed where there are two passages and, for example, an air two-thirds of this flows through the second passage and only one-third flows between the ball and the tube. Assume that

In this case, according to the 2.5 width law, the gap between the ball and the tube is is reduced to approximately 6496 of the air gap when passing between the ball and the tube. No. This provides several important advantages. First, the manufacturing of the pipe The tolerance in construction is that the size of the air gap is not a linear determinant of the collision sensor calibration. Therefore, it can be significantly alleviated.

Second, it is unlikely that the ball will move in the center of the tube or along the wall. It becomes unimportant. Third, as mentioned in the description of this invention, the assembly of parts Precise adjustment of the balance sensor calibration can be made during the Further relaxing requirements for precision manufacturing of stick or aluminum tubes can do. And fourth, by providing a second passage for air, the tube You can choose from a wide range of materials. Thermal expansion coefficient of ball and tube The required difference in is a function of the portion of air that bypasses the air gap between the ball and the tube. Therefore, a wide range of coefficients of thermal expansion can be used to compensate for changes in air viscosity due to temperature. It becomes possible to select from materials that have

One method of creating a second passageway for airflow is to create grooves within the cylindrical outer surface of the tube. and by positioning this tube within a second tube in which it fits snugly. be. In this assembly, the length of the resulting air channel is the length of the ball and tube. many times longer than the effective axial length of the air gap between. For example, the length of the groove is It may be ten times longer than the effective axial length of the air gap between the roll and the tube. air The viscous resistance to flow is proportional to the length of the channel, so for smaller dimensions The groove can be larger than the air gap between the ball and the tube. grooves have air gaps between them In extreme cases, such as two equally wide pipes, the pressure drop will be The depth of one groove varies according to the cubic power of the air gap, so the depth of one groove varies according to the actual distance between the ball and the tube. It will be larger than the effective air gap by a cube root of 10 or approximately twice the air gap.

Furthermore, the channel created by the groove is only a fraction of the circumference of the tube. , whereby the depth of the groove may be further increased by a factor of approximately 4.

A ball with a diameter of approximately 1 mm is well within the capabilities of plastic molding technology. Dimensions for a groove on the order of 4/1000ths of an inch in a crash sensor with The above analysis yields. A collision sensor with a ball approximately 2 mm in diameter is The above analysis is based on aluminum die casting technology and aluminum drawing technology. A groove with a depth on the order of 10 CIO 5 inches is within the capabilities of both techniques. bring.

One method for achieving temperature compensation is when the void includes a groove within the cylindrical outer surface of the tube. The method creates a tube including a groove and a second tube of material having a different coefficient of thermal expansion. It is about making.

The grooves may also be located on the inner diameter of the tube, so that the balls are located on the inside diameter of each channel. Form one side. In this configuration, the benefits of the larger air passage length are Not done.

If this is a collision sensor that has a ball with a similar diameter to the diameter of the current collision sensor, If done, the airflow through the shorter channels is less viscous and has the desired properties. ability will not be achieved. However, collision cells with very small balls In this collision sensor, the air flow is viscous7, and in this design, a metal ball is By making and has a larger coefficient of thermal expansion than the coefficient of thermal expansion of the ball Thermal compensation may be achieved by making the tube of material such as plastic. stomach. Channel air between the ball and the tube, as in the case of a collision sensor where the groove is on the outside diameter of the tube. By passing air through the grooves, you have a wider range of material choices compared to collision sensors that pass through the grooves. becomes significantly wider.

“Mechanical Collision Sensing Switch with Latching in Closed Position” cal Crash SSen5-1n Swi tch Wi th Lat At the same time titled ChingIn The C1osed Po5ition) J Pending U.S. patent application Ser. No. 166.044 describes the normal rest position of a moving mass. It is also possible to compensate for temperature changes in air viscosity by changing the so its mass is transferred farther at a lower temperature before bridging the contact. by keeping it moving and not moving too far at high temperatures. , teaches that compensation can be achieved.

Until now, there have been seven technologies for collision sensors with viscous damped moving elements. Important factors are not recognized.

First, by reducing the size of the ball and tube, changes in air viscosity with temperature can be improved. For all types of compensation, depending on the different coefficients of thermal expansion in the ball and tube, In collision sensors, a stable material made of thermoset plastic or aluminum is used. This results in a requirement for the coefficient of thermal expansion that can be matched by the part. is not recognized. Second, reduce the size of the ball and tube by a large factor. This substantially increases the size of the void relative to the size of the part, and Therefore, the relative manufacturing tolerances of plastic or aluminum tubing Significantly larger than currently manufactured parts, further improving effectiveness It has been recognized that it is substantially easier to satisfy reduced parts not present. Third, manufacturing tolerances allow air to flow more into the channel than between the ball and tube. It is not recognized that it can be further alleviated by passing it through. Fourthly, with the ball A channel bypassing the air gap between the pipe and the molding process or the pultruded aluminum can be easily made by forming a groove in the mini rod, and The collision sensor is constructed by selectively blocking a fraction of the channel during assembly of the collision sensor. It is not recognized that it can be calibrated by Fifth, some of the air is A wider range of materials can be applied to the tube by passing it through the channel than between the tube and the tube. It is not recognized that it will be possible to use . Sixth, semiconductor switch In combination with a smaller ball, smaller balls and tubes can be used. , since the requirements for contact dwell and resistance are substantially reduced. It is not recognized that it exists. Seventh, the groove on the inner diameter of the tube is on the outer surface of the ball When the diameter of the ball is small enough, it will allow air to pass through it viscously. It is not recognized that it forms flannel.

Brief description of the drawing FIG. 1 shows a schematic diagram of the crash sensor and diagnostic system of the present invention, and shows a pyrotechnic system. Indicates a fuse for initiating a surgical action and indicates an operator warning light.

FIG. 2 shows a crash sensor of the invention in a vehicle having a safety sensor with a diagnostic resistor. Figure 2 shows a schematic diagram of the sensor and diagnostic system.

Figure 3 shows how this method requires only two wires for each crash sensor and diagnostic device. 1 shows a schematic diagram of one embodiment of the crash sensor and diagnostic system of the invention; FIG.

Figure 4 shows a section in section and the ball in its normal or rest position. , which shows the complete crash sensor of this invention.

FIG. 5 shows the crash sensor shown in FIG. Shown in closed position bridging contacts to initiate operation.

Figure 6 is a partially cut-away version of Figure 4 to show the location of certain components. FIG. 6 is a top view of the collision sensor shown in FIGS.

FIG. 7 shows a device mounted on an elastic support to reduce sensitivity to orthogonal axis vibrations. 1 is a partially cutaway view of the crash sensor and diagnostic system of the present invention; FIG.

FIG. 8 is a schematic diagram of the circuit of the present invention.

FIG. 9 shows two crash sensors of the invention positioned within the same housing. vinegar.

FIG. 10 is the same schematic diagram as shown in FIG. 7, but with additional switches. and related components.

Figure 11 is similar to Figure 7, but requires only two wires. FIG. 2 is a schematic diagram showing a collision sensor and a diagnostic device.

Figure 12 is for interfacing with the crash sensor and diagnostic equipment of Figure 11. FIG. 2 is a schematic diagram of a diagnostic module.

FIG. 13 is a schematic diagram of the signal generator of the circuit of FIG. 11;

FIG. 14 includes a tube with grooves forming channels that vary in size with temperature. 1 is a cross-sectional view showing a part of the collision sensor of the present invention.

FIG. 15 is a cross-section of the tube and housing taken along line 15-15 of FIG. It is a diagram.

FIG. 16 is a cross-section of the tube and housing taken along line 16-16 of FIG. It is a diagram.

FIG. 17 shows a cross-sectional view of the tube of the present invention showing a ball with a groove on its inner diameter. vinegar.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE PREFERRED EMBODIMENTS OF THE INVENTION Examples are shown in crash sensors and diagnostic systems. Figures 1 and 2 in particular By reference, the crash sensor and diagnostic system 10 detects acceleration pulses indicative of a crash. a collision sensor 12 for detecting a collision; and a fuse 14 that closes when a collision is detected. and a semiconductor switch 150 for supplying power to the occupant protection device shown as nothing. Additionally, the crash sensor and diagnostic system 10 detects a defective ignition circuit. Diagnostic circuit to detect a defective ignition circuit and close the operator A flip-flop shown as a switch 222 for powering the warning light 16. 222. The ignition circuit is energized to begin deploying the occupant protection system. This is a circuit external to the crash sensor and diagnostic system 10. In Figure 1, The ignition circuit includes a conductor to the fuse 14, the fuse 14, and a complete circuit through the fuse 14. ground connection. In FIG. 2, the ignition circuit further includes a safety sensor 19. . Upon detecting a collision, the solid state switch 150 initiates operation of the occupant protection system. It closes and remains closed as if it were closed. When detecting a defect in the ignition circuit, the switch Flip-flop 222, shown as 222, closes and turns off warning light 16. and alert the vehicle operator. FIG. 2 further shows that the current reaches the fuse 14. safety sensor 19 electrically located in a position that must be closed in order to including. Safety sensor 19 includes a fused diagnostic resistor 219.

With particular reference to FIG. 3, the crash sensor and diagnostic system 400 is configured to a collision sensor 12 for detecting acceleration pulses, and a collision sensor 12 for detecting acceleration pulses that a semiconductor switch for supplying power to the occupant protection device, shown as a fuse 14; 150. Crash sensor and diagnostic system 400 further detects defective Detects the ignition circuit and transmits information about the state of the ignition circuit via the ignition circuit conductors. Contains diagnostic circuitry for communication. The ignition circuit in Figure 3 crash sensor and diagnostic system 400 that is activated to initiate the It is a circuit. The ignition circuit includes a conductor to the fuse 14, the fuse 14, and the fuse 14. and a ground connection to complete the circuit. The ignition circuit also includes a fuser resistor 219 The safety sensor 19 may also include a safety sensor 19 having a. The diagnostic module 4U0 is the ignition circuit receives the information transmitted through the conductor and that there is a defect in the ignition circuit. When this occurs, the warning light 16 is turned on to alert the vehicle operator. no information This indicates an error in the ignition circuit and therefore the diagnostic module. 410 turns on the operator warning light 16.

As the description progresses, it will be noted that the invention may be implemented in different embodiments. That will be understood.

This invention, which eliminates electronic circuits, is shown in Figures 4 to 7, Figures 14, 15, and This will be explained below with reference to FIGS. 16 and 17.

With reference to Figures 4 to 7, Figures 14, 15, 16 and 17, , the collision sensor 12 to bridge the two electrical contacts 32 and 34. The ball 20 has a gold-plated outer surface. The ball 20 is connected to the tube 24 and 124 within the cavity 22 or between the normal rest position and the semiconductor chip 42. moving within housing 224; Semiconductor chip 42 is coupled to base 44 . In the embodiment shown in FIGS. 1 and 5, tube 24 and bimetal washer 28 is inserted into the cavity 46 of the housing 48, and the ball 20 extends inwardly. The bimetal washer 28 has a normal rest position relative to the fingers 26.

In the embodiment shown in FIGS. 14, 15, and 16, tube 124 is connected to the housing. is inserted into the cavity 146 of the plug 148 .

In the embodiment shown in FIG. 17, the tube and housing are mated to housing 224. Ta. In the embodiments shown in FIGS. 14, 15 and 16, the normal static state of the ball is The stop position is opposite the inner surface 96 of the housing 48. Implementation shown in Figure 17 In the example, the ball's normal rest position is in the cavity (not shown) of housing 224. facing the end.

Cavity 22 is connected to ball 20 and tubes 24 and 124 or housing 224. It is thus divided into chambers 21 and 23. Housing 48.148 and 2 24 is preferably made of extrusion cast injection molded plastic. tube 2 4 and 124 have grooves on their outer periphery and one end, which allows the ball 20 air channels 66 and ] 66, respectively, through which air viscously flows as it moves. produce. The housing 224 has a groove on its inner periphery that allows the ball 20 to move. When moving, it creates an air channel 226 through which air flows viscous. The tube 24 is a tube 24 with adhesive applied in a sufficient number of locations to ensure retention of the It is held in place within the barrel 46. The second purpose of the adhesive 52 is to calibrate the collision sensor. be. Adhesive 52 can be used to close multiple channels 66, Accurately determine the resistance to air flow from chamber 21 to chamber 23.

This allows the air duct to be opened during the manufacturing process subsequent to inserting the tube 24 into the cavity 46. Insert a drilled ball of precisely known diameter into the tube 24 and While measuring the flow rate, the chamber 23 is pressurized and the tube 2 is adjusted to give the desired flow rate. This is achieved by adding adhesive 52 around the 4. Or, Figure 14, As shown in FIGS. 15 and 16, tube 124 is located within housing 148. It may be held in place within cavity 146 by a retaining ring 86 within groove 88 .

/% radial positioning of the cylinder 1240 with respect to the housing 148 124 to the lip 98, which has a slightly reduced inner diameter of the reservoir to hold it tightly. Thus, it is fixed to the bottom of the cavity 146.

At the top of cavity 146, lip 102 on cylinder 124 is shown in FIG. It is inserted tightly into the 11 housing 148 so that the on cylinder 124 Flat unit 04 allows air through channel 166 to pass through lip 102 be able to. In the embodiment shown in FIGS. 14, 15 and 16, the housing The tube 148 is made of a material with a higher coefficient of thermal expansion than the tube 124. and the bimetal washer 28 having fingers 26 extending inward is omitted. has been done. Openings 92 in retaining ring 86 allow air to flow automatically into channel] 66. You can pass through it freely.

In the embodiment shown in FIG. 17, housing 224 has channel 266 dimensioned to Thermal expansion of ball 20 varies with temperature to compensate for changes in air viscosity with temperature It is made of a material that has a coefficient of thermal expansion that is sufficiently larger than the coefficient.

Contacts 32 are connected to pads ( (not shown) at point 36. One way is This is ultrasonic welding. The contacts 34 are connected to pads (not shown) on the semiconductor chip 42. is connected to point 38 (not shown).

One end of the housings 48, 148 and 224 abuts the semiconductor chip 42.

A small amount of adhesive holds the housing in place over the semiconductor chip 42, especially during assembly. do. A magnet 54 is positioned by a stem 56 of the housing.

The base of the ferromagnetic cup 58 abuts the magnet 54. annular ring on the housing 29 is elastically bendable and has manufacturing tolerances within the diameter of the housing and ferromagnetic The cup 58 is accommodated. Terminals 126.160.202.234 and 254 are , semiconductors by conductors 122, 158, 200, 232 and 252, respectively. Connected to pads 128.162.204.236 and 256 on chip 42 Ru.

Please refer to FIG. 6 for an explanation of the terminals, pads and conductors. Other fruits of this invention In the example, there are only three terminals on the housing. In this example, only three There are three terminals and three pads, but the rest is similar to the system shown in Figure 6. It will be similar. The cover 62 having an annular elastic cushion 64 is completed. flange 68 provided on the assembly and by soldering or other means. The device is attached to the base 44 and hermetically sealed. This invention is a low power A package similar to the standard To-')05AD package commonly used for Shown inside the cage.

Any other suitable semiconductor encapsulation method may be used. Other common semiconductors In the body encapsulation method, the base 44 is formed of plastic and is thermosetting. Resin is applied to the entire assembly to form cover 62. when electric current is transferred Since the distance is very short, heat sinking capacity is not required for semiconductor mounting It should be noted that

During normal operation of the vehicle, fingers 26 extend inwardly of bimetallic washer 28. the ball 20 with greater force than is sufficient to hold the ball 20 against the A magnet 54 is applied to attract it to itself. Ferromagnetic cup 58 is magnet 5 4, thereby transmitting the magnetic force on the ball 20 or the magnetic force at the ball's location. Therefore, the magnet 54 is used more efficiently.

(Margin below) Referring now to FIG. 7, crash sensor and diagnostic system 400 detects vibrations caused by a crash. Mounted on an elastic support to separate the sensor. Collision sensor and elastic support be enclosed in an external enclosure that can withstand the elements. Elastic supports are placed inside the outer enclosure. Collision sensors and diagnostic systems in a plane perpendicular to the tube axis provide limited movement. make it possible to do

The illustrated crash sensor and diagnostic system connects two wires to the vehicle's electrical system. This is an embodiment that requires only a layer.

A crash sensor and diagnostic system requiring only two wires is shown schematically in FIG. are mentioned below with reference to.

The resilient support is preferably a material such as rubber that is bonded to the washer 71 during the molding process. It includes a cup-shaped elastic support 70 made of. Collision sensor and diagnostic system 4 00 is placed opposite the bottom 72 of the elastic support 70 and is held by a lip 73. It will be done. Guide wires 74, 75 and 76 in elastic supports 70 and washers 71 A channel is provided. The washer 71 is installed on the shelf 77 of the can 80 in the external enclosure. and positioning is performed accordingly. Printed board 78 supports capacitor 404 And the guide wires 74 and 76 are connected to the harness wires 81 and 82. P Lint base 78 also connects inductive wires 74 and 75 to the terminals of capacitor 404. Continue. Since the number of connections is small, the printed board 78 can be omitted and methods such as ultrasonic welding can be used. It may be preferable to connect the components directly. Preferably A spacer such as an elastic washer 83 formed in the same molding process as the elastic support 70 is It may be included between washer 71 and printed board 78. Cup 84 is external welded to complete the enclosure and provide a weatherproof seal on the outside area. or by other suitable means. Preferably along with meltable material 87 An elastic wrapper 85 manufactured by shrinking heat-shrinkable material is attached to the cup 84. provides a weatherproof seal at the entrance of wires 81 and 82. filamen The wires 90 provide longitudinal strength to the wrapper, which may also This is accomplished by crimp 91 of the smaller diameter portion of cup 84 around it.

The electronic circuit of the invention will now be described with reference to FIG. contact 32 is connected to the trigger input of the monostable multivibrator 120, and the contact 34 is connected to the trigger input of the monostable multivibrator 120. Connected to the positive voltage side of the vehicle's electrical system via conductor 122 and terminal 126 be done. The monostable multivibrator 120 has a battery voltage applied to its trigger input. except that its output reaches a logic high and remains there for about 1 second after being applied. Usually applied to have a low pressure signal. The signal generator 130 generates one signal per second. is applied to generate a square wave output at a frequency of 1 cycle. It preferably oscillates 16384Hz or IMHz frequency and bias This is an oscillator that operates with a Naris scaler, etc. It is a predetermined 1 second in its output The number of cycles per cycle is given to a logic high signal. Logic high inhibit via conductor 168 When a signal is received, the logic high output signal of the IHz signal generator 130 sufficient to allow the crash sensor and diagnostic system to complete diagnostic tests. delayed for several minutes. Its output is connected to logic OR circuit 1 via conductor 136. 40. The output of the monostable multi-bi break 120 is a conductor 138 to the other input of logic OR circuit 140. Occupant protection system At the point when it is necessary to supply vehicle power to the fuse 14 of the A zero output is a logic high.

The semiconductor switch 150 is a Sensefet MOS in FIG. Illustrated as a power transistor. The drain electrode 152 of sensefnit is The positive terminal of the vehicle electrical system is connected via conductor 154 and conductor 122 and terminal 126. connected to the voltage side. The source electrode 156 of the semiconductor switch 150 is the conductor 15 8 and terminal 160 to the fuse 14 of the occupant protection system. semiconductor Body switch 150 is controlled by a signal at its gate electrode 164 . gate electric When the signal at pole 164 is approximately 10V higher than the signal at source electrode 56, it is completely so that the signal at gate electrode 164 is approximately the same as the signal at source electrode 156. When the voltage is applied it is fully opened.

The circuit driving the semiconductor switch 150 is a triple delay circuit that together operates as a voltage doubler. circuit 170, capacitor 172, diode 174, inverter 176 and switch A switching transistor 178 is included. The voltage doubler circuit was chosen because it This is because it offers the possibility of implementation on a single semiconductor circuit. Capacitor 17 All components of the drive circuit except 2 are formed on the semiconductor chip 42. .

Capacitor 172 is preferably a small ceramic capacitor, made of a semiconductor chip. It may be bonded directly to a pad (not shown) on top 42 or otherwise. It may be located at a location.

The circuit that drives the semiconductor switch 150 operates in accordance with the output signal of the logic OR circuit 140. The required voltage is provided at the gate electrode 164. The output of logic OR circuit 140 is logic low. , the voltage at the gate electrode 164 of the semiconductor switch 150 is equal to the voltage at the source electrode 1 It is approximately the same as the voltage at 56. If the output of the logic OR circuit 140 is logic high, , the voltage at gate electrode 64 is approximately 12 V greater than the voltage at source electrode 156. . A circuit that provides drive to the semiconductor switch 150 according to the output of the logical OR circuit 140 are stated in the paragraphs below.

Triple delay circuit 170 provides three delayed logic high signals at its three outputs. in response to a logic high signal provided to its input via conductor 144. output each is delayed differently. The signal with the minimum delay is routed through conductor 182. is supplied to the anode of diode 174. The signal from the cathode of diode core 4 The signal is applied to terminal 186 of capacitor 172 via conductor 184 and also to terminal 186 of capacitor 172. 184 to the gate electrode 164 of the semiconductor switch 150. The delayed signal is applied via conductor 188 to terminal 192 of capacitor 172. It will be done. The non-delayed output of logic OR circuit unit 40 is connected to inverter 17 via conductor unit 42. 6) Given to input. The output of the inverter 176 is the switching transistor 1 78 and controls whether it is conductive or not. inverter When the output of 176 is a logic high, switching transistor 178 conducts. , when the output of the inverternia 6 is logic low, the switching transistor 17 8 is not conductive. The source electrode 194 of the switching transistor 178 is connected to the conductor 2. 00 and terminal 202 to the ground side of the vehicle electrical system. Swish The drain electrode 196 of the switching transistor 178 is connected to the semiconductor strip via the conductor 184. It is connected to the gate electrode 164 of the switch 150.

High/low comparator 220, flip-flop 222, diode 225, diode A circuit including a lead 226 and a resistor 228 connects to the sensing electrode of the semiconductor switch 150. 230, the voltage at the source electrode 156 of the semiconductor switch 50, and the triple 1, 0 to monitor the most delayed signal from the delay circuit near 0 and the resistance of the ignition circuit. Hz signal generator 130 output signal, and conductor 232 and terminal 23. 4 to control the operator warning light roller. The most delayed signal from the triple delay circuit 170 The signal is provided via conductor 238 to the data input of flip-flop 222. It will be done. The ignition circuit voltage is applied via conductor 168 to a 1.0 Hz signal generator 130. Supplied to the north input. 1 of the signal generator 130; The output of OH2 is via conductor 240. and is supplied to the reset input of flip-flop 222. High/low comparator 22 The zero output is provided via conductor 242 to the set input of flip-flop 222. Ru. The output of flip-flop 222 is a set signal and a data signal that are simultaneously asserted. reaches and remains at a logic high when the reset signal goes from low to When it reaches a logic high it reaches a logic low and stops there. Output of high/low comparator 220 means that the input signal received via conductors 244 and 246 is less than a predetermined amount. It is logic high when there is a difference by a large amount. First of all, semiconductor switch 50 was A small number of source cells are electrically isolated from the majority of source cells in the eighth section. MOSFET power connected to a separate external terminal shown at 230 in the diagram. It is a transistor. The solid state switch consists of two upper elements on a 150 resistor bridge. It functions when it is in the on state as a ment. The two lower elements of the bridge G is the ignition circuit and resistor 228. The value of resistor 228 is the resistance of the ignition circuit. When the resistance is small and the semiconductor switch 150 is conducting, the conductor 246 The voltage on conductor 244 is determined to be equal to the voltage on conductor 244. flip flop The output of 222 is connected to the operator via diode 225, conductor 232 and terminal 234. data warning light 16.

Terminal 254, conductor 252 and diode 226 are used by the driver to turn on the vehicle's ignition. when moving the switch 18 to the start position via the conductor 232 and the terminal 234. power to the operator warning light 16. Diodes 225 and 226 are The signals from the ignition switch and flip-flop 222 are energized by the output circuit of flip-flop 222 and the ignition switch. Prevent interference with the circuit.

An embodiment of the invention in which two collision sensors are combined in parallel is shown in FIG. It is also stated. Crash sensor and diagnostic system 310 detects acceleration indicative of a crash. It includes two collision sensors 12 and 12- for detecting pulses, each of which detecting a collision and shutting off power to the occupant protection system, illustrated as fuse 14; 150 and 150, respectively. Each collision sensor detects a defective ignition circuit and indicates the condition of the ignition circuit on the ignition circuit conductor. There is also diagnostic circuitry for transmitting the information to the diagnostic module 410. Diagnostic module 41 0 by closing switch 450 on the information that there is a defect in the ignition circuit. Respond by turning on the operator warning light 16 on the vehicle's dash board.

The ignition circuit may also include a safety sensor unit 9. Semiconductor switch when a collision is detected 150 and 150' are closed and closed to initiate operation of the occupant protection system. It remains as it is. For diagnostic purposes, solid state switches 150 and 150' are turned off. It is closed periodically to provide a small amount of power to the arc circuit. Check the ignition circuit for defects. Upon learning, crash sensor and diagnostic system 310 detects the defect in diagnostic module 410. Vary the timing of the ignition circuit test to inform. Test pulse tie Switch 450 alerts the vehicle operator upon detecting a change in timing. is closed in order to turn on the warning light 16.

A safety sensor] 9 may also be included, if so it is a current fuse] 4 electrically placed in a position that must be closed in order to reach.

A second embodiment of the electronic circuit of the invention will now be described with reference to FIG. Ru. Semiconductor switch 50 has two semiconductor switches in series for greater reliability. The circuit of FIG. 10 except that it has been replaced by switches 50 and 350. is the same as the circuit shown in FIG. Required to drive the semiconductor switch 350 Some other components may also be duplicated to achieve greater reliability. Ru.

Certain other components are not duplicated in the circuit of FIG. assists in driving both the switch 150 and the semiconductor switch 350. semiconductor The component used to drive switch 150 is semiconductor switch 3 It will be apparent to those skilled in the art that there are many different aspects that can be shared with 50. It will be. In particular, it includes contacts 32 and 34 that detect the ball 200 or so. It is possible and desirable to duplicate all components that return them Will.

The semiconductor switch 350 is a MOSFET switched power transistor in FIG. Illustrated as a star. The source electrode 356 of the semiconductor switch 350 is the conductor 354 It is connected to the drain electrode 152 of the semiconductor switch 150 via.

The other electrodes of the semiconductor switch 150 are as described above with reference to FIG. connected to the sea urchin. Drain electrode 352 of semiconductor switch 350. is the conductor 358 and 122 and to the positive voltage side of the vehicle electrical system via terminal 126. It will be done. Semiconductor switch 350 is controlled by a signal at gate electrode 364. Game When the signal at source electrode 364 is approximately IOV higher than the signal at source electrode 356 It is applied to be completely closed and the signal at gate electrode 364 is sourced. It is suitable to be fully open when the voltage is approximately the same as the signal at the ground electrode 356. used.

The circuit driving the semiconductor switch 350 is a logic O circuit that operates as a voltage doubler. R circuit 140, triple delay circuit 170, capacitor 372, diode 374, input includes an inverter 376 and a switching transistor 378. semiconductor switch and a non-predetermined capacitor 372 to be on the semiconductor chip 42. The components of the drive circuit except for the May be on a conductor chip (semiconductor chip 42) or on a different semiconductor chip (not shown) may also be used. Capacitor 372 is preferably a small ceramic A semiconductor chip-shaped pad (Fig. (not shown) or placed elsewhere.

The circuit that drives the semiconductor switch 350 operates according to the output signal of the logic OR circuit 140. provides the required signal at the gate electrode 364. The output of the logic OR circuit 140 is -, the voltage at gate electrode 364 of semiconductor switch 350 is approximately ground. Located at electric potential. When the output of logic OR circuit 140 is at logic high, gate electrode 36 The voltage at 4 is approximately 12V greater than the voltage at source electrode 356.

Turn-on of semiconductor switch 350 is initiated by triple delay circuit 170.

The least delayed signal from triple delay circuit 170 is routed to the diode via conductor 382. is supplied to the anode of the board 374. The signal from the cathode of diode 374 is is provided to terminal 386 of capacitor 372 via conductor 384 and also to terminal 386 of capacitor 372. 4 to the gate electrode 364 of the semiconductor switch 350. intermediate delay A signal requiring . The non-delayed output of logic OR circuit 140 is inverted via conductors 144 and 342. 376. The output of inverter 376 is a switching transistor. applied to the gate of resistor 378 and controls whether it is conducting or not. stomach When the output of inverter 376 is at a logic high, switching transistor 378 conducts and the switching transistor is turned on when the output of inverter 376 is at a logic low. Star 378 is not conductive. Source electrode 394 of switching transistor 378 ground the vehicle electrical system via conductors 200 and 300 and terminal 202. connected with the side. The drain electrode of switching transistor 378 is connected to conductor 384 It is connected to the gate electrode of the semiconductor switch 350 via.

Requires only two wires from the crash sensor and diagnostic circuit to the vehicle electrical system A third embodiment of the electronic circuit of the collision sensor and diagnostic system of the present invention is the eleventh embodiment. 12 and 13, described herein with reference to FIGS. Opposition in Figure 11 The circuit of the shock sensor and diagnostic system 400 receives a signal from a 1°0Hz signal generator 130. Replaces generator 430 and three connections to the vehicle electrical system and certain connections The circuit shown in FIG. 8 is the same as that of FIG. 8, except that the circuit shown in FIG. collision sensor and diagnostic circuit 400 also detects that diode 402 and capacitor 404 and the output of flip-flop 222 is a reliable signal rather than operator warning light 16. The circuit differs from the circuit of FIG. 8 in that it is connected to the input of a signal generator 430. da Iode 402 and capacitor 404 are directly connected between conductor 154 and conductor 158. Connected to columns. Conductor 154 connects to the high voltage side of the vehicle electrical system via terminal 126. connected to. Conductor 158 is connected at all times except when power is applied to fuse 14. The fuse 140 is connected via the terminal 160 to the ignition circuit side, which is at ground potential at that moment. It will be done. Connection point 406 between diode 402 and capacitor 404 is connected to Crash sensor and diagnostic system 400 powered and thereby at all times maintain steady-state operation and connect it to the vehicle's electrical system with only two conductors. Provide a source of ground potential at times including FIG. 13 shows the signal generator 430. and functional blocks within the signal generator 430 are shown. Figures 11 and 13 The electronic circuitry shown is designed to operate in accordance with the diagnostic module 410 shown in FIG. It is measured.

The diagnostic module 410 shown in FIG. The diagnostic circuit interprets the timing of the ignition circuit test pulse from 0 and detects the timing of the ignition circuit test pulse. When it is determined that a malfunction has been detected, the operator warning light 16 is turned on.

Diagnostic module 410 is described below. They are resistor 412 and resistor 414 ．． 10KHz signal generator 416, pulse detector 418, scaler 426 and pinary comparator 4 with an output applied to drive the pelleter warning light 16 Contains 28. Pulse detector 418 is used to monitor the ignition circuit at conductor 422. detecting that the fuse 14 is being applied and power of the vehicle electrical system is being applied to the fuse 14. When doing so, it provides an output signal to conductor 424. The pulse detector 418 is a monostable multi It may be a level sensing comparator accompanied by a vibrator or a predetermined any other circuit suitable for emitting a signal when a level shift is detected. It may be. Resistor 412 isolates diagnostic module 410 from the ignition circuit. This ensures that a failure in the diagnostic module 4 unit 0 prevents the deployment of the occupant protection system. eliminate any possibility of 10KHz signal generator 4] 6 is a 26 and to the crash sensor and diagnostic system 400, resistor 41 to the ignition circuit. 4. Provides the tarok signal via conductor 422 and resistor 412. 10KH The frequency of z is exemplary and any other suitable locking frequency may be substituted. Ru. In particular, to obtain times in multiples of 1 second when a binary scaler is used, A frequency of 16384 Hz is suitable for this purpose. Resistor 414 indicates that it is the ignition circuit part. Reduce the magnitude of the clock signal so as not to interfere with signal detection. The clock signal is to the pulse detector 418 via the conductor 432, and the pulse detector 4]8 Distinguish the clock signal from the ignition circuit pulse using the signal received through the input of the You can help them separate. Scaler 426 receives the clock from 10KHz generator 416. The cycles of the lock signal are counted and each output signal from the pulse detector 4]8 is counted. Applied to be reset to zero by the tracking edge.

Scaler 426 also outputs the current count of clock cycles to binary comparator 42. applied to give 8. Binary comparator 428 receives the clock from scaler 426. the current count of clock cycles and the maximum number maintained within itself or elsewhere. and the output of scaler 426 indicates a defect in the ignition circuit. Operator warning light 16 via terminal 434 when a predetermined numerical limit is exceeded. applied to supply power to

The signal generator 430 detects the state of the ignition circuit and finally the signal generator 430 outputs the output signal. Generates a timed signal according to the number of ignition circuit tests completed since the occurrence do. The signal generator 430 includes a 1.0KHz filter 442, a scaler 444, and a scaler 444. 446 and a binary comparator 448.

A 10KHz filter 442 is received from signal generator 416 via conductor 168. 10 KHz clock signal from other signals on the ignition circuit and scale. 446 is applied to provide a clean 10) CHz signal. Scaler 4 44 is applied to provide a specific binary value to a binary comparator 448. given The value received via conductor 408 is determined by whether the circuit's conditional input received via conductor 408 is at a logic high or not. conductor 168 since the last output signal from signal generator 430 depending on how many test pulses are received from the ignition circuit via the ignition circuit. a specific tuple of values is discussed below in the description of the operation of signal generator 430. The scaler 446 is Counts the number of clock cycles since the last test pulse on the ignition circuit is applied to provide that count to a binary comparator 448. binary comparison When the device 448 determines that its two binary inputs are equal, it sends an output signal to the conductor 240. applied to give to This output signal applied to conductor 240 is the circuit of FIG. is the output of signal generator 430 to the path.

(Margin below) Next, the operation of the collision sensor and diagnostic system of this invention excluding the electronic circuit is @4 7, 14, 15, 16 and 17. It will be. In the operation of this system, the ball 20 is attracted by the magnet 54. is held in its normal rest position by. A deceleration much greater than 1g will cause a collision of ball 20, as would occur during a car crash, when given a Inertia causes it to move from its normal rest position and electrical contacts 32 and 3 Make it move towards 4. Because of this movement that occurs, the air in chamber 21 some of the ring between ball 20 and tube 24.124 or housing 224. chamber through the shaped void or through the channel 66.166 or 266. It is necessary to proceed to step 23. Minimize uncertainty in resistance to viscous flow Because of this, the clearance between the ball and the tube is such that air predominates in the channel 66. ．． It should be something like passing 166 or 266. ball and tube air transport, whether through the air gaps between the The movement is resisted by air viscosity, which causes the pressure in chamber 21 to A pressure difference is caused in a state where the pressure is greater than 3. This pressure difference is the movement of the ball 20. The motion is directed toward the electric foot tacts 32 and 34 so that a predetermined Contact is not achieved until a velocity change occurs.

Contact 34 to ball 20 when the ball contacts both electrical contacts. Current flows through the contact 32.

At lower ambient temperatures the clamp between ball 20 and tube 24 or 124 or 224 The clearance is reduced because the coefficient of thermal expansion of the tube is greater than that of the ball. It is the body. This is due to the movement of air through the clearance gap at lower temperatures. increases viscous resistance to However, most air channel designs , the change in the air gap between the ball and the tube compensates for the change in air viscosity due to temperature. probably won't. The tube is made of plastic with a very large coefficient of thermal expansion. If there is no air gap between the ball and tube, there is a substantial amount of air between the ball and tube. The differential thermal expansion of the tube relative to the ball is It will not fully compensate for the reduced air viscosity.

In the embodiment illustrated in FIGS. 4 and 5, the flap of bimetal washer 28 is causing finger 26 to vary the normal rest position of ball 20 as a function of temperature; Additional compensation can be obtained by At lower temperatures, finger 26 is in contact. 32 and 34, changing the rest position of the ball 20 and contacting it. increases the travel distance required to bridge ports 32 and 34. Than At high temperatures, fingers 26 bend toward contacts 32 and 34, causing the bow to necessary to change the resting position of contact 20 and bridge contacts 32 and 34. Reduce the required travel distance. The relationship between the ball and cylinder at lower temperatures The clearance between the and at higher temperatures the clearance increases, thereby to a certain extent Compensate for higher air viscosity at higher temperatures. Bimetal washer 28 is temperature The clearance between the ball 20 and the tube 24 is changed by changing the resting position of the ball. In addition to the compensation resulting from changes in the air gap due to temperature, what additional compensation is required? I will give it as compensation.

In the embodiment illustrated in FIGS. 14, 15 and 16, the housing 1 The different coefficients of thermal expansion of tube 48 and tube 124 are necessary due to changes in air viscosity with temperature. Provide necessary compensation. At lower temperatures, tube 124 is not inside housing 148. They always fit tightly and the gap 94 between them is very narrow. As the temperature rises The housing 148 expands at a greater rate than the tube unit 24, and the void 94 increases. Ru.

However, over the entire operating temperature range, the air gap 94 remains narrow, resulting in Even at the highest operating temperatures, a small amount of air with little gas passes through the air gap 94. Giru. Air predominates when the tube and housing expand differently. It passes through a channel 166 whose intensity changes. When the temperature rises the housing 14 8 expands more rapidly than tube 124, which increases the height of channel 166 and its This allows easier passage of air through the channels and allows for easier passage of air at higher temperatures. to compensate for high air viscosity. When the temperature decreases, the housing 148 4, it decreases the height of channel 166, thereby reducing the Makes the passage of air through the flannel more difficult and lower air viscosity at lower temperatures Compensate for.

In the embodiment illustrated in FIG. The coefficient of thermal expansion provides the necessary compensation for changes in air viscosity with temperature. low At low temperatures, housing 224 fits very tightly around balls 20 and The air gap 294 between them is very narrow. As the temperature increases, the housing 224 The air gap 294 expands at a greater rate than the ball 20, and the void 294 increases. however, Over the entire operating temperature range, the air gap 294 remains narrow, resulting in the highest operating temperatures. Even at high temperatures, a small amount of air with little smoke passes through the air gap 294. air The predominant one is that the height changes when the ball and housing expand differently. passing through channel 266. As the temperature rises, the housing 224 expands more rapidly than channel 20, which increases the height of channel 266, thereby increasing the allows easier passage of air through the channels and allows for easier passage of air at higher temperatures. Compensate for air viscosity. When the temperature decreases, the housing 224 will be lower than the ball 20. rapidly shrinking, which reduces the height of channel 266, thereby causing the channel to Makes the passage of air more difficult and compensates for lower air viscosity at lower temperatures do.

In one embodiment of the invention, temperature compensation is provided for the material from which the ball and tube are made. THEORY OF AIRDA to be accurate According to the analysis presented in the chapter entitled MPED CRAS)l 5ENSOR8) to select the diameter of the ball 20 and tube 24 or 124 or housing 224. By doing so, a total compensation of temperature effects on air viscosity is achieved. In this example In this case, there is no need for an air channel and the tube 24 or 124 and the housing 48 or 148, respectively, such as housing 224 illustrated in FIG. But one plastic molded model without flutes to form air channels. may also be combined into a

The advantage of this design is that in some materials it is easier to produce tubes without axial channels. That is probably the case. One disadvantage is that the ball position is not very good. not specified, which can result in changes in performance, as discussed above. be. A second disadvantage is that the choice of material is subject to certain differences between the coefficients of thermal expansion of the ball and tube. In other words, it is more limited by the needs of

Referring now to FIG. 7, the operation of a vibration isolation installation will be described. cup-shaped The elastic support 70 extends the side of the cup in the direction of impact sensor and diagnostic system 4. For a motion of 00, it is It's very resistant. During a car crash, the crash sensor (in the direction of the axis of ball motion) ) subjected to axial acceleration that may exceed 1.00 g (100 times the acceleration of gravity) Ru.

Axial acceleration tends to stretch the sides of the elastic support 70; Collision sensor and diagnostic system 4 that resists and therefore axial acceleration Send directly to 00. During a motor vehicle crash, lateral or cross-axis accelerations of similar magnitude also occur. There may be. Crash sensors are insensitive to cross-axis acceleration (unlike vibration) and that it connects the ball 20 to one side of the tube 24, 124 or housing 224. It only has the effect of making the parts roll. For sufficiently high cross-axis accelerations, collisions The portion of the elastic support 70 closest to the sensor and collision sensor is the elastic support or housing. Move sideways until it touches the wall at 80. Frequencies exceeding 200 cycles per second and Cross-axis vibrations occur with maximum accelerations approaching 100 g. these vibrations The ball 20 is caused to vibrate within the tube or roll around the periphery of the tube. ball 2 to contacts 32 and 34. 0 movement is slow and undesirable. The elastic support 70 has an external enclosure that is connected to the collision sensor and and diagnostic system 400 to allow cross-axial vibrations with minimal transmission. isolates the crash sensor and diagnostic system 400 from cross-axis vibrations.

(Margin below) The operation of the electronics of the crash sensor and diagnostic system will now be described with reference to FIG.

The collision detection function of the circuit will be explained first, followed by the diagnosis function.

When ball 20 straddles contacts 32 and 34, the positive voltage of the vehicle electrical system is A voltage on the voltage side is applied to the trigger input of the monostable multivibrator 120. child This causes the output of monostable multivibrator 120 to go to logic high for about 1 second. stay at that level for a while. This level is transmitted via conductor 138 to logic OR circuit unit 40. is given to one input. This causes the output of the logic OR circuit 140 to become the logic no. Proceed to Step A to energize the ignition circuit and activate the occupant protection system.

The ignition circuit is energized when the semiconductor switch 50 is closed. semiconductor switch 15 To close 0, the voltage on gate electrode 164 is approximately 1.0 with respect to source electrode 156. 0 volts must be raised to positive.

During normal operation, the voltage on gate electrode unit 64 is applied to switching transistor 178. Therefore, it is maintained at a low level.

Before the high control signal is applied to the gate electrode 164, the switching transistor 178 is turned off. To accomplish this, the output of logic OR circuit 140 is The output of inverter 176 goes to logic low, and this logic low level is applied to the gate of switching transistor 178 and turns it off. .

sufficient to ensure that switching transistor unit 78 is in its off state. After a delay of 30 seconds, the triple delay circuit near 0 turns on its minimum delay signal. This signal is to terminal 186 of capacitor 172 via diode 174 and to semiconductor switch 1 50 gate electrodes 164. At this time, the disconnection from the triple delay circuit 170 The continuously delayed signal is a logic low and is applied to terminal 192 of capacitor 172. is being applied. The signal from diode 174 increases the voltage on gate electrode 164. and charges the capacitor near 2 to the high output voltage of the triple delay circuit 170.

After a delay sufficient to ensure that capacitor 172 is fully charged, the Delay circuit 170 provides an intermittent delay of the delay applied to terminal 192 of capacitor 172. Turn on the signal. The capacitor 172 handles this voltage increase through a semiconductor switch] 50 to gate electrode 164, which serves to turn on semiconductor switch 50. increase the voltage to the required level.

By turning on the solid state switch 150, the positive voltage of the vehicle electrical system is turned on. side voltage is supplied to the ignition circuit via conductor 158 and terminal 160 to provide occupant protection. Activate protection system operation.

The diagnostic function of the circuit of FIG. 8 will now be described. The circuit diagnostic section shows that the resistance of the ignition circuit is Constructed to turn on operator warning light 16 when not within established limits. move. To accomplish this, the output of flip-flop 222 is preset with a resistor. Set to logic high whenever it is determined to be outside the defined limits. Ru. The output of flip-flop 222 connects operator warning light 16 to diode 2. 25.

The resistance of the ignition circuit is determined once every second by the process described below. . One cycle per second was chosen because it is a suitable frequency, but the test This may be done at any suitable frequency. The output of the 11 Rohrtz signal generator unit 30 is applied to the logical OR circuit 1400 Å power and to the reset input of the flip-flop 222. This is the test signal.

The signal generator 130 is tested when other crash sensors are testing the ignition circuit. 1 through conductor 168 without generating a signal. 0 Hz signal generator] 30 prohibited entry until the inhibit signal supplied to the power returns to low level before generating the test signal. Designed for waiting and waiting. ], by the logic high output of the 0 Hertz signal generator 130. Thus, the output of logic OR circuit 140 goes to a logic high during the test pulse. circuit collision In the same manner after describing the sensing function, the test pulse from the logical OR circuit 140 is turns on semiconductor switch 150 for the duration of each test pulse.

If the resistance of the ignition circuit is outside the predetermined limits, the test pulse will also be set. The flip-flop 222 is reset in preparation for the start. Test pulse is occupant protection equipment has a sufficiently short duration that the fuse 14 at the location is not heated.

The resistance of the ignition circuit is determined by comparing the voltage applied to the resistor 228 and the voltage applied to the ignition circuit. I\B--determined by comparator 220. As explained above, ignition When the resistance of the circuit is at its nominal value, the voltage across resistor 228 is 50 is in the on state, equal to the voltage across the ignition circuit. If the resistance of the ignition circuit is within predetermined limits with respect to the nominal value and the semiconductor switch 150 is in the on state. , the voltage across resistor 228 is within predetermined limits across the ignition circuit. and the output of comparator 220 is at a logic low. difference If not, it's in logic high.

Semiconductor switch 150 confirms that the output of No1Elow comparator 220 is stable. After being on for a sufficient period of time to realize the The extended signal is provided to the data input of flip-flop 222. flip flop If the set input of step 222 is also logic /\, this means that the resistance of the ignition circuit is As would have happened if it were outside the defined limits, the flip-flop 222 is placed in the set state and its output goes to the noise level, and the diode 225, transmitted by conductor 232 and terminal 234 to operator warning light 16 Been turning it on.

If it is turned on, the operator warning light 16 will remain on for one second. and then turned off by the next test pulse. The resistance of the ignition circuit is limited. If the driver continues to be out of bounds, operator warning light 15 will be turned back on immediately. It seems to be continuously on for Iba.

In the embodiment of the invention shown in FIG. is the combined resistance of all wiring and fuse resistances and the resistance of diagnostic resistor 219 It is. The resistance of the diagnostic resistor 219 is the resistance of the collision sensor 12. ng) If sensor 19 closes when it is not, it will cause the occupant protection system to deploy. sufficient to prevent. For a typical system, this is diagnostic resistor 2 19 is approximately 100Ω. This is due to the diagnostic resistance of the current system. ignition circuit conditions much lower than that possible with current systems. Allows to determine much more accurately. The diagnostic resistor 219 detects the storage battery circuit voltage. is given to it for a very long period of time, for example 10 seconds, the solution will open. It may also be a fusible resistor. If the diagnostic resistor opens, it will disable the occupant protection system. in the collision sensor that may be caused by semiconductor failure. protection against short-circuit conditions, and by opening such diagnostic resistors, operation The controller warning light 16 indicates that the ignition circuit resistance is outside of predetermined limits. turned on.

The inhibit signal given to the 1.0 Hz signal generator is determined when more than one collision sensor is lit. ] more collisions by preventing simultaneous testing of arc circuit resistances. Allows the sensor to be connected to the ignition circuit. If two collision sensors fire ignition circuit and the first crash sensor tests the ignition circuit resistance. A high voltage in the circuit is applied to the inhibit input of the 1.0 Hertz signal generator of the second crash sensor. the test pulse until the first crash sensor completes its test. It will be delayed. Similarly, a second crash sensor tests the resistance of the ignition circuit. If so, the 1.0 Hertz signal generator of the first crash sensor delays that signal. . Two crash sensors connected in parallel are placed in the same housing as shown in Figure 9. It may be stored or mounted at different locations on the vehicle. In the former case, System reliability is increased because if one crash sensor fails, the other This is because it causes the deployment of the occupant protection system during a collision.

The operation of the second embodiment of the crash sensor and diagnostic system electronics is illustrated in FIG. I will explain. The circuit of FIG. 10 includes a semiconductor switch 350 and related components. The circuit is the same as the one shown in FIG. 8, except for the addition of components. All components described above The semiconductor components operate in the same manner as described above with respect to FIG. The drain electrode of the body switch 150 is connected to the source electrode of the semiconductor switch 350. It receives power only when the semiconductor switch 350 is conducting.

Closing of semiconductor switches 150 and 350 energizes the ignition circuit. semiconductor Closing of switch 150 has already been described with reference to FIG. semiconductor switch 350 The voltage on gate electrode 364 is approximately 10 volts with respect to source electrode 356 to close must be raised to the highest level.

During normal operation, the voltage at gate electrode 364 is applied by switching transistor 378. is maintained at a low level. A control signal of /%a is given to the gate electrode 364. Before switching, switching transistor 378 is turned off. To achieve this If the output of the logic OR circuit 140 goes to logic no, the output of the inverter 376 goes to a logic low and a signal is applied to the gate of switching transistor 378. Turn it off.

ensuring that switching transistors 178 and 378 are in the off state After a delay sufficient for , triple delay circuit 170 turns on its minimum delay signal. this The signal is routed through diode 374 to terminal 386 of capacitor 372 and to semiconductor A gate electrode 364 of switch 350 is provided. At this time, the triple delay circuit 17 The signal delayed from 0 intermittently is a logic low and is connected to terminal 39 of capacitor 372. It is given to 2. The signal from diode 374 changes the voltage at gate electrode 364. and charges capacitor 372 to the high output voltage of triple delay circuit 170. Ru. After a delay sufficient to ensure that capacitor 372 is fully charged, 3 Double delay circuit 170 intermittently delays the voltage applied to terminal 392 of capacitor 372. Turn on the signal. The capacitor 372 transfers this voltage rise to the semiconductor switch 3. 50 gate electrode 364, which increases its voltage to the required level. to turn on the semiconductor switch 350. Turning on semiconductor switch 350 , the voltage on the positive voltage side of the vehicle electrical system is routed through conductor 354 to the semiconductor strip. is supplied to the drain electrode of switch 150. The semiconductor switch 350 is a semiconductor switch. The semiconductor switch 150 is turned on at the same time as the switch 150, as shown in FIG. enabling it to operate in the same manner as described. However, if a semiconductor switch whether the chip 150 is commanding its gate voltage to conduct to it. If it fails in such a way as to cause it to conduct continuously, the semiconductor Power is passed through the semiconductor switch 150 to the fuse 1 until the switch 350 is turned on. 4, thereby causing the internal Preventing the deployment of occupant protection devices caused by short circuits. Furthermore, the semiconductor switch 15 0 failure almost guarantees that its internal resistance will cause the high-low comparator 220 to indicates a malfunction of the occupant protection system and the driver is alerted to the malfunction. Change as you gain.

(Margin below) The operation of the third embodiment of the electronic portion of the crash sensor and diagnostic system is illustrated in FIG. , 12, and 13. The operation of the circuit in Fig. 11 is as follows. The operation is the same as that of the circuit shown in Figure 8, but the 1.0 Hz signal generator 130 is Replacing 430 is the timing of the test pulse applied to fuse 14. affect. All components in the circuit of Figure 8 are described above with respect to Figure 8. The circuit of FIG. 11 operates in the same manner as described above. diode 402 and capacitor 404 are added to stabilize the power supply voltage, Allows operation with only two connections to the vehicle's wiring system.

Diode 402 and capacitor 404 are the logic connections of the components of FIG. Connect the ground circuit to fuse 1 through diode 402, conductor 158, and terminal 160. Connect to 4.

It operates by Except for certain brief periods when a pulse is applied to the fuse 14. , the fuse acts as an approximately 1 Ω resistor to ground, thereby causing connection point 406 to In most cases it is grounded by diode 402. Battery voltage is the ignition When applied to line 14, diode 402 isolates node 406 from high voltages. Capacitor 404 then stabilizes the voltage at node 406.

The timing of the test pulses for testing the ignition circuit is explained below. Ru. The circuit of FIG. 11 connects the vehicle power to the fuse 14 when the circuit of FIG. 8 is high. Continue. The output of a logical OR circuit is logical when any of its inputs is a logical no. This is due to the fact that ball 20 is in contact, as mentioned above with respect to Figure 8. when bridging ports 32 and 34 or when the output of signal generator 430 is a logic noise. It happens when.

Signal generator 430 applies a short period of time to conductor 240 to begin testing the ignition circuit. Logic No. 1 output signal is placed periodically.

The timing of these signals is accurate to convey information about the state of the ignition circuit. controlled by. The specific timings shown below are specific. A person skilled in the art is appropriate You may replace it with other timing. Additionally, those skilled in the art will recognize that analog timing circuits Other timing circuits, including those described herein, may also be used to achieve equivalent functionality. It is clear that the circuit can be replaced with the one shown in the figure. The times received via conductor 408 A logic high on the road condition input indicates that an incorrect ignition circuit resistance has been detected; Signal generator 430 generates an output signal at 8 second intervals. The conductor 408 connects the receiver to the If the input circuit status input is a logic low, which is a normal condition, signal generator 430 will Issue a timed output signal according to: After issuing the output signal, Before any subsequent test signal is received via conductor 168, the signal generator 430 waits for 3 seconds to elapse after generating an output signal, and then generates another output signal. do. If a test pulse is received via conductor 168 before 3 seconds have elapsed , signal generator 430 begins another waiting period after receiving the test pulse. Wait for 2 seconds to elapse and then generate another output signal. Before 2 seconds have passed If a second test pulse is received via conductor 168 at begins another waiting period until 1 second has elapsed since receiving the second test pulse. and generate another output signal.

If the vehicle occupant protection system includes three crash sensors and a diagnostic system 400, Let's think about the normal operation of the body. First crash sensor and diagnostic system 400 confidence Signal generator 430 generates an output signal that causes the test pulse to be applied to the firing circuit. It is assumed that the signal has just been issued and that there is a waiting process of 3 seconds before issuing the output signal. Set. However, each signal of the second and third crash sensor and diagnostic system 400 Signal generator 430 detects the test pulses just issued to the ignition circuit and each is in the waiting process for less than 2 seconds before issuing the next output signal. 2nd and 3rd opposition One of the signal generators 430 of the crash sensor and diagnostic system 400 is connected to the first crash sensor. output signal before the signal generator 430 of the sensor and diagnostic system 400. do. The test pulses provided are applied to the first crash sensor and diagnostic system 400. signal generator 430 to begin another waiting period and generate an output signal. Wait 2 seconds for the screen to appear. However, the second and third crash sensors and diagnostic systems One of the signal generators 430 senses the previous two test pulses issued to the ignition circuit. and is in the process of waiting for 1 second before issuing the next output signal. Therefore, that The output signal of signal generator 430 of first crash sensor and diagnostic system 400 issued before. The resulting test pulse is applied to the first crash sensor and the diagnostic system. causing the signal generator 430 of the stem 400 to begin another waiting period and output Wait 1 second before generating a signal. In this cycle, the second and third impulses The other two signal generators 430 of the impact sensor and diagnostic system 400 The output signal is more recent than the signal generator 430 of the sensor and diagnostic system 400. signal, and each one is in the waiting process for more than 2 seconds for the next output signal to be issued. Ru. The signal generator 430 of the first crash sensor and diagnostic system 400 Issues the output signal when 1 second has elapsed since the test pulse, and outputs the output signal to the first collision sensor. The sensor and diagnostic system 400 issues test pulses. All collision sensors and diagnostic unit 400 operate similarly, so they each run the test pattern in turn. The three work together in a cyclical manner to generate pulses at 1.0 second intervals. to generate a test pulse in the ignition circuit.

If the ignition circuit is defective, the operation of the crash sensor and diagnostic system 400 considered above may be affected. Consider the case where the

For example, if one of the crash sensors and diagnostic systems 400 becomes disconnected or Assume that detects an ignition circuit resistance that is out of tolerance. In both cases, wait 1 second. If it is your turn to apply a test pulse to the ignition circuit after this period, it will not be done. . Each signal generator 430 of two further crash sensor and diagnostic systems 400 is in the process of waiting for 2 seconds or more before issuing its next output signal. death Therefore, the next test pulse occurs after an interval of 2 seconds rather than the normal interval of 1 second. Given. For similar reasons, any combination of failures will result in a test pulse of 1 second. It has been found that this results in collisions occurring at different intervals, resulting in all collision sensors being when the sensor and diagnostic system 400 are connected to measure the correct diagnostic circuit resistance. This results in a system in which test pulses are applied to the ignition circuit at intervals of 1 second. three A similar system may be configured using something other than crash sensor and diagnostic system 400. It is clear that it is possible to calculate the You can get the same result by doing

The operation of diagnostic module 410 is described with respect to FIG. diagnostic module 410 operates to monitor the ignition circuit and measure the time interval between test pulses. However, if the test pulses do not occur at the expected 1 second time intervals, the vehicle's instrument panel Turn on the operator warning light 16. The 10 kilohertz signal generator 416 is 1 at any time to generate a clock signal at a rate of 100,000 per second. A detector 418 is provided to generate the signal. Additionally, the tarok signal is connected to resistors 414 and 4. 12 as well as a voltage divider comprising a series combination of squibs 14. , given to the ignition circuit. The scaler 426 receives the tarok signal via a conductor 432. increments that counter each time a reset signal is received at its count input. Reset the counter to 0 each time it is received on its reset input via conductor 424. adapted to be used. Pulse detector 418 monitors the ignition circuit and It generates a logic high signal on its output conductor 424 during each diagnostic pulse it detects.

It uses a 10 kHz clock signal received on conductor 432 to generate a diagnostic pulse. may further help distinguish the clock signal from the clock signal. Distinguish that signal from another signal. Means for using signals differently are well known in the communications arts and are described herein. No further explanation is given. The output of pulse detector 418 is connected via conductor 424 to Provided to the reset input of Kohler 426. Binary comparator 428 is scaler 4 Compare the digital output of 26 with the maximum value of 10000, which is 10 in 1 second. corresponds to the number of clock cycles generated by the kilohertz signal generator 416. vinegar If the digital output of Koehler 426 exceeds 10,000, the binary comparator 42 8 provides power through conductor 436 and terminal 434 to activate operator warning light 16. turn on.

The operation of signal generator 430 is described with respect to FIG.

Signal generator 430 provides a 10 kHz clock signal and conductor 16 from the ignition circuit. 8 test pulses and uses that information to test the ignition circuit. generates a signal that initiates a test pulse for testing. 10 kilohertz frequency Filter 442 transmits a diagnostic module 410010 kilohertz signal on conductor 168. receives a 10 kHz clock signal placed in the ignition circuit by signal generator 416; and amplifies it to drive scaler 446. Scaler 446 is 0 km Continuously counts the Hertz clock signal from the 10 kHz filter 442; The binary value of that counter is provided to a binary comparator 448. Scaler 446 is ignited The binary value of that counter is reset to O by each test pulse of the circuit. is the time in units of 0.0001 seconds from the most recent test pulse. binary ratio Comparator 448 outputs a logic high from its output on conductor 24 when its two inputs are equal. 0, otherwise a logic low. Binary applied to conductor 240 The output of recomparator 448 is the output of signal generator 430 and provides a test pulse to the ignition circuit. It is logic high at the appropriate time to start the process. Scaler 444 is connected via conductor 408. and from binary comparator 448. test received on conductor 168 from the ignition circuit since the most recent logic high output signal of Depending on the number of pulses, a binary digit is generated. Give it to the scale input. For normal operation i.e., the circuit status input received via conductor 408 is a logic low. and the output is a binary signal initialized by a logic high output from binary comparator 448. is a number and is decremented by each test pulse received on conductor 168 from the ignition circuit. be done. For example, if the clock speed is 10 kilohertz, the scaler 444 is 3 Initialized to 30,000, the number of clock cycles in seconds, the ignition circuit is decremented to 20.000 when a test pulse is first received on conductor 168. , and is again decremented to 10.000 when a second test pulse is received; Thereby, the output pulses of the signal generator 430 are 1; 3 seconds, 2 seconds, and 1 second. causing an interval. Scaler 444 does not decrement below 10,000. point If the arc circuit is defective, the circuit status input received at conductor 408 will be a logic high. , and the output of scaler 444 is forced to a binary digit corresponding to 8 seconds. 8 seconds The exact value of the circuit state input received via conductor 408 is not important; When the logic is high, forcing the output turns on one or more higher order output lines. This can be easily achieved by turning it on. Thus, signal generator 430 through conductor 408 if there is a defect in a two-sting circuit operating in the following manner. The circuit status input received by the scaler 446 is a logic high and the scaler 446 increments by 1 each clock cycle until 8 seconds have elapsed since the test pulse; When the output of scaler 446 is equal to the output of scaler 444 in one clock cycle, , the output of binary comparator 448 is on the output conductor during that clock cycle. 240 to logic l~a. During normal operation, the circuits received via conductor 408 The road condition input is a logic low. In order to provide a starting point, in the following explanation, the signal generation Assume that generator 430 has just provided an output signal on conductor 240. tentative In the given situation, scaler 446 has just been reset to zero and the scaler 446 has controller 444 has just been set to a binary digit corresponding to a 3 second clock cycle. It is. Therefore, in the hypothetical situation, scaler 446 is the last ignition circuit. Increment by 1 for each clock cycle until 3 seconds have elapsed since the test pulse, and then When the output of scaler 446 is equal to the output of scaler 444 in one crotter cycle, and the output of binary comparator 448 is equal to the output conductor during that tarok cycle. Raise 240 to logic I\I. However, during normal operation, another collision sensor and Diagnostic system 400 places a test pulse on the ignition circuit before three seconds have elapsed. Guidance The test pulse received at body 168 resets scaler 446 to zero and 444 to a binary digit corresponding to a two second clock cycle. previous situation and Analogously, in the hypothetical situation, scaler 446 performs the last ignition circuit test. increment by 1 each clock cycle until 2 seconds have elapsed since the start. The output of scaler 446 is equal to the output of scaler 444 in one clock cycle. The output of binary comparator 448 is connected to output conductor 240 during that clock cycle. to logic high. During normal operation, another collision occurs, such as in the case of a 3 second wait time. Sensor and diagnostic system 400 applies a test pulse to the ignition circuit before two seconds have elapsed. put A test pulse is received on conductor unit 68 and resets scaler 446 to zero. and decrements scaler 444 to a binary digit corresponding to one second clock cycle.

In this case, scaler 446 waits until one second has elapsed since the last firing circuit test pulse. is incremented by 1 for each clock cycle, then the output of scaler 446 is 1 clock equal to the output of scaler 444 in the lock cycle and binary comparator 448 The output of will raise the output 4 output 240 to logic/temperature during that clock cycle, and generates an output signal that starts a test pulse 1 second after the previous test pulse. let That is, signal generator 430 receives the circuit state received via conductor 408. If the input is logic high, the output pulse will be output 8 seconds after the last test pulse of the ignition circuit. If the circuit status input is a logic low, the binary comparator 448 has been received on conductor 168 from the ignition circuit since Depending on whether the test pulse is 0, 1 or 2, the last of the ignition circuit Set the output pulse to issue an output pulse 3 seconds, 2 seconds, and 1 second after the test pulse, respectively. It operates to maintain the value in the caller 444.

Although the description of this invention has been given in terms of particular embodiments, it is not to be taken in a limiting sense. It's not something you can do. Many variations and modifications may occur to those skilled in the art. invention Please refer to box i of the accompanying claims for the provisions of the following.

Special table 13-500348 (22) International study report -keh1-＾6111ul#N6. ．． ．． -q, c, ,,.

Claims (18)

[Claims] 1. In a type of collision sensor that includes a movable pole in a sealed tube, the distance traveled is while the tip includes means for pushing the pole into its normal rest position; and detecting means for detecting when the other end of the tube approaches the other end of the moving distance; filled with a medium, with a gap between the pole and the tube so that the viscous medium a first liquid for viscously transmitting from one side of the pole to the other side of the pole; The improvements include: viscous medium from the one side of the pole to the other side of the pole; A collision sensor comprising second liquid conduit means adapted to communicate. 2. including an axial groove formed in the inner diameter of said tube, said second liquid conduit means 2. The method of claim 1, comprising a channel defined by the axial groove and the pole. The invention described. 3. The pole and the tube are made from materials with different coefficients of thermal expansion; The tube has a coefficient of thermal expansion sufficiently larger than that of the ball, and has a coefficient of thermal expansion that is Global compensation of viscosity changes is achieved by thermal expansion of the tube with respect to the ball. The invention according to claim 1. 4. The ball and the tube are made of materials with different coefficients of thermal expansion; The tube has a coefficient of thermal expansion sufficiently larger than that of the ball, and has a coefficient of thermal expansion that is Global compensation of viscosity changes is achieved by thermal expansion of the tube with respect to the ball. The invention according to claim 2. 5. a first crash sensor adapted to detect a vehicle crash; In the type of occupant protection system where the ignition circuit is completed by incorporating means suitable for determining whether the resistance of said ignition circuit is within predetermined limits; an occupant protection system, the occupant protection system including the first crash sensor being integrated with the first crash sensor; 6. The resistive sensing means directs substantially the entire voltage of the vehicle electrical system to the ignition circuit. periodically, and the ignition cycle is applied while the full voltage of the vehicle electrical system is applied. 6. The invention according to claim 5, wherein the resistance of the road is measured. 7. Claim comprising a second collision sensor connected in parallel with the first collision sensor. The invention described in 5. 8. determining the state of the ignition circuit by transmitting an electrical signal to a conductor of the ignition circuit; 6. The invention as claimed in claim 5, comprising means adapted for communicating information regarding. 9. determining the state of the ignition circuit by transmitting an electrical signal to a conductor of the ignition circuit; 7. The invention as claimed in claim 6, comprising means adapted for communicating information regarding. 10. Said means adapted for communicating information comprises said ignition circuit of said full voltage. 10. The method according to claim 9, comprising means for controlling the timing of said application to invention. 11. In a type of collision sensor that includes a movable ball in a sealed tube, the distance traveled includes means for pushing the pole into its normal rest position at one end of the and detecting means for detecting when the other end of the travel distance is approached, and the tube is viscous. filled with a viscous medium, with a gap between the ball and the tube to fill the viscous medium. a first for viscously transmitting the body from one side of the ball to the other side of the ball; The improvements include providing liquid conduit means; A crash sensor comprising resilient means adapted to support said crash sensor. 12. The elastic means is less elastic in the axial direction of the tube than in the vertical direction. The invention according to claim 11. 13. The elastic means includes an elastic material extending in the axial direction of the tube; The elastic material extends in a direction defined by two cylinders concentric with the axis. 12. The invention according to claim 11, existing in pace. 14. a first collision adapted to close the first switch upon detecting a collision; sensing means and a second switch adapted to close the second switch upon sensing a collision; In the type of occupant protection including collision detection means, the first and second switches Both switches must be closed to begin deploying the occupant protection system. Connected in series, the improvements are as follows: connected in parallel with one of said switches and when voltage is applied for more than a short period of time. Occupant protection system comprising electrically resistive means adapted to stop conduction of electricity. 15. said short period is between 0.01 seconds and 1000 seconds in duration; The invention according to claim 14. 16. Electricity in a motor vehicle having an enclosure and wires entering said enclosure In the air device, the improvement is adapted for the path by which the wire enters the enclosure. said enclosure having a tubular element wrapped around said tubular element; , and a wrapper surrounding a length of the wire, the length of the wire being the length of the wire. external to the tubular element and adjacent one end of the tubular element; the wrapper is placed around the tubular element and on the length of the wire; a heat shrinkable tube lined with a meltable material that melts the meltable material; an electrical device that is heated sufficiently to cause the heat-shrinkable tube to shrink; 17. 17. The heat-shrinkable tube of claim 16, comprising filaments parallel to the axis of the heat-shrinkable tube. invention. 18. 16. The tube segment is crimped around the wire. The invention described in .