CA2026921A1 - Velocity change sensor with adjustment screw - Google Patents
Velocity change sensor with adjustment screwInfo
- Publication number
- CA2026921A1 CA2026921A1 CA002026921A CA2026921A CA2026921A1 CA 2026921 A1 CA2026921 A1 CA 2026921A1 CA 002026921 A CA002026921 A CA 002026921A CA 2026921 A CA2026921 A CA 2026921A CA 2026921 A1 CA2026921 A1 CA 2026921A1
- Authority
- CA
- Canada
- Prior art keywords
- accelerometer
- housing
- inertial element
- path
- passenger restraint
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000008859 change Effects 0.000 title description 4
- 230000003213 activating effect Effects 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 claims description 4
- 230000004044 response Effects 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 208000027418 Wounds and injury Diseases 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 208000014674 injury Diseases 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000002674 ointment Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P15/135—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by making use of contacts which are actuated by a movable inertial mass
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H35/00—Switches operated by change of a physical condition
- H01H35/14—Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H35/00—Switches operated by change of a physical condition
- H01H35/14—Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch
- H01H35/141—Details
- H01H35/142—Damping means to avoid unwanted response
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Air Bags (AREA)
- Switches Operated By Changes In Physical Conditions (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An accelerometer for activating a passenger restraint system in a motor vehicle includes a housing with a passage for defining a path of movement, and an inertial element moving in said path. Either a mechanical or a magnetic member is used to bias the inertial element toward a preset position. The preset position is defined by a presetting member which is adjustable so that the accelerometer is responsive to crashes with a tolerance of ? 1 MPH.
As the inertial element moves away from the preset position in case of a crash, it closes an electrical contact for deploying the passenger restraint system
An accelerometer for activating a passenger restraint system in a motor vehicle includes a housing with a passage for defining a path of movement, and an inertial element moving in said path. Either a mechanical or a magnetic member is used to bias the inertial element toward a preset position. The preset position is defined by a presetting member which is adjustable so that the accelerometer is responsive to crashes with a tolerance of ? 1 MPH.
As the inertial element moves away from the preset position in case of a crash, it closes an electrical contact for deploying the passenger restraint system
Description
-`"2~26~2~ -B~KG~OUND OF TH~ ~NVENTION
This invention pertains to a velocity change sensor or accelerometer used in motor vehicles for detecting sudden chan~es in velocity and for ac~ivating in response a passenger restraining device such as an air bag. More particularly, this device includes an element which moves to a preset position in response to a sudden deceleration to close an electrical contactl said device also having adjustment means for presetting a position of said element to increase the sensitivity of the sensor.
10Studies have been made which indicate that injuries in motor ~ehicle accidents, especially at high speeds, can be ~ substantially reduced or eliminated by the use of passenger ;`~ restraint systems. (The term "passenger" is used to cover the driver of a car as well). These systems include an inflatable balloon usually termed an air bag which normally is stored away in the instrument panel or the steering wheel. When the motor vehicle is subjected to a sudden deceleration, the air bag is inflated and is deployed automatically in a position which cushions the passengers, restrains their movement and prevents contact between them and the automobile interior such as the windshield, the steering wheel, the instrument panel and so on. Of course, a cr~cial element o~ all such systems is the velocity change sensor ;or accelerometer which initiates the inflation and deployment of the air bags. The motion of the motor vehicle must be carefully and precisely monitored so that th~ air bags can be deployed very fast, before the passengers suffer any substantial injury.
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A velocity change sensor is disclosed in U.S. Patent No.
~,329,54~ assigned to the same company as the present invention.
This sensor comprises a tubular housing surrounding a metallic shell, a metal ball and a magnet biasing the ball toward a first end of the shell. ~t the second end of the shell there are a pair of electrical contact blades. The sensor is positioned in the motor vehicle in an orientation such that when the motor vehicle experiences a deceleration which exceeds a present level, the ball moves from the first toward the second end, making contact with the two blades. Because the blades and the ball are made of an electrically conducting material, when the ball contacts the blades, an electrical path is established between the two blades.
This electrical path is used to initiate a signal for the deployment of the air bags.
; 15 Accuracy of the sensor described in U.S. Patent No.
4,329,549 depends on the proper alignment of the two electrical contact blades. The sensitivity, i.e. the minimal deceleration that sets off the sensor is determined by the strength of the magnet, and the initial position of the ball. It was found that because of variations in dimensions of the sensor during the manufacturing process, the sensor has a tolerance of about +2MPH.
In practice this tolerance is not acceptable in the industry because if the sensor triggers at deceleration which is too low, a restraint bag may be triggered when the car is not involved in a crash ~i.e. at 8 MPH) causing the driver to lose control over the motor vehicle. If the bag is set to trigger only when the vehicle experiences a very high deceleration (i.e. a crash at above 12 :
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MPH), it may not go off on actual crash, and would fail in its ~unction of protecting the passengers.
8U~MARY OF ~E INVENTION
In view of the above mentioned disadvantages of the prior art, it is an objective of the present invention to provide a ;restraint system in which the sensitivity time, i.e. the deceleration at which the bag restraint system i5 deployed can be preset to accurate value.
A further objective is to provide a restraint system with a velocity sensor in which a moving element has a presetable initial position for a reduced tolerance.
A further objective is to provide a sensor which is easy and inexpensiva to manufacture, and in which critical elements need not be made with high precision because the sensitivity of the sensor may be adjusted for each until after assembly.
`Other objectives and advantages of the invention shall become apparent from the following description. An accelerometer constructed in accordance with the invention includes a housing with contact blades and a contacting element which provides an electric path between the blades when a deceleration above a threshold level is sensed. An adjusting means is also provided for presetting th~ position of the element. Thls presetting adjusting means is adjusted after the assembly of the sensor to cooperate for diminished variations of its components as well as for variations ; 25 in the field strength of the magnet, if any. With this feature, it has been found that sensors can be made which can be adjusted to trlyger a section of the bag system in response to a crash of a given velocity, when said sensor may be present at an accuracy of t- 1 MPH.
` 5BRII~F DESCRIPTION OF T~IE DR~WINGS
These and other ob~ects and advantages of the invention will become apparent upon reading the following detailed description and upon referring to the drawings in which:
. FIGURE 1 shows a side elevation view of a first 10 accelerometer constructed in accordance with the invention disposed in a case;
FIGURE 2 shows in a side cross-sectional an alternate embodiment for the accelerometer of FIGURE l; and FIGURE 3 shows in a cross-sectional view, a second 15 accelerometer constructed in accordance with the invention.
While the invention will be described in conjunction with an example embodiment, it will be understood that it is not :intended to limit the invention to such embodiment. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
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ETAILED DEFIC~RIPTION OF q!~ll3 INVENTION
In the drawings, similar features have been given similar reference numerals.
The sensor shown in Figure 1 consists of a housing 12 with an interior chamber 14 holding a ball 16. The chamber 14 defines a movement path between a first end wall 24 and a second end wall 26 of chamber 14 for the ball 16 and a spring blade 18 is used to bias the ball and hold it in abutment with end wall 22, as shown in Figure 1. The sensor is positioned in a motor vehicle so that if the vehicle crashes as a preselected minimum speed, the ball, under the influence of the deceleration resulting from the crash, overcomes the biasing force of spring blade 18 and starts moving along the path defined by chamber 14 toward the opposite end wall 26. As the ball moves along its path, it pivots spring blade 18. When the spring blade 18 hits a second blade 20 an electric :contact is made which is used to generate an electric signal to a control means for triggering a passenger restraint system such as an air bag (not shown).
An important feature of the invention is the provision of preset screw 22 threaded and extending through the end wall 24 with its head 28 disposed outside the housing 12, and with its proximal end 30 being in contact with ball 16 in the rest position, as shown in Figure 1.
~The response of the sensor depends on a number of factors : 25 including the weight of the ball, the dimensions of the sensor, the spring constant of blade 1~ and so on. By varying these ,; . .~ l ,. . : , :
parameters, the sensor can be built to sense and respond to a present deceleration~ For example, -the parameters may be selected so that the sensor activates the passenger restraint system when a crash is sensed at a nominal speed of 10 MPH. ~Iowever, because of variat.~ons in these parameters which occur during the manufacturin~
process, the sensor has a characterist.ic error or tolerance of + 2 MPH. As previously mentioned this tolerance may be unacceptable.
However, it has been discovered that in a sensor constructed in accordance with this invention this tolerance ca~ be reduced considerably. More particularly, the rest position of the ball 16 may be adjusted with the preset screw 22. Advancing the screw causes the ball to move slightly away from end wall 24. Retrieving the screw from the housing causes the ball 16 to move slightly closer to the wall 24. In this manner the present velocity of the ~ 15 sensor, i.e. the velocity at which a crash will cause a sensor to activate a passenger restraint system may be preset with an accuracy or tolerance of ~ 1 MPH.
In the embodiment of Figure 1, the preset screw 22 is abutting dixectly ball 16 with end 30. In order to increase the contact area between the screw and the ball, a disk 32 may be attached to the screw end 30 as shown in Fiyure 2. In this manner the amount of wear and tear between the screw and the ball is reduced considerably. The disk is even more ef~ective if it is . attached rotatably to screw 22.
; 25 A different type of sensor 110 is shown in Fi~ure 3.
This sensor, similar to the sensor described in U.S. Patent No.
4,329,549, has a ho~sing 112 with an interior shell 114 made of '~
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2 ~ 2 ~
magnetically permeable material. ~he housing 11~ has to opposed end walls 124, 126. End wall 126 holds two blades 118, 120 which in this configuration have similar shapes and sizes. A permanent magnet 134 is disposed outside housing 112. Within the housing 112 there is also a ball 116 having a diameter slightlv smaller than shell 11~. I'he ball is also made of a magnetically permeable material. The shell 114, ball 116 and magnet 134 are constructed and arranged so that the magnetic field generated by the magnet biases the ball to the rest position shown in Figure 3. When the sensor is disposed in a motor vehicle in such a manner that, in a crash at a speed above a preselected level, ball moves toward wall 126. When it contacts blades 118, 120, an electrical signal is generated by well known means in the art. The signal is sent for example on wires 136, 138 to a passenger restraint system 140 for activating it. Again, without the preset screw 122, the sensor has a tolerance of about -~2 MPH. This tolerance is reduced to about ~1 ; MPH by adjusting screw 122 to move the ball 116 either toward or away from end wall 124.
- Obviously numerous modifications may he made to the invention without departing from its scope as defined in the appended claims.
Thus it is apparent that there has been provided in accordance with the invention that fully satisfies the objects, aims and advantages set forth above. While the invention has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing - ~:: .~ . , -, . ' : ' ' ,: . ~ ~ ,, :.
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description. Accordingly, it is intended to embrace all such alternatives, modiications and variations as fall within the spirit and broad scope of the invention.
, ~ , .
.
This invention pertains to a velocity change sensor or accelerometer used in motor vehicles for detecting sudden chan~es in velocity and for ac~ivating in response a passenger restraining device such as an air bag. More particularly, this device includes an element which moves to a preset position in response to a sudden deceleration to close an electrical contactl said device also having adjustment means for presetting a position of said element to increase the sensitivity of the sensor.
10Studies have been made which indicate that injuries in motor ~ehicle accidents, especially at high speeds, can be ~ substantially reduced or eliminated by the use of passenger ;`~ restraint systems. (The term "passenger" is used to cover the driver of a car as well). These systems include an inflatable balloon usually termed an air bag which normally is stored away in the instrument panel or the steering wheel. When the motor vehicle is subjected to a sudden deceleration, the air bag is inflated and is deployed automatically in a position which cushions the passengers, restrains their movement and prevents contact between them and the automobile interior such as the windshield, the steering wheel, the instrument panel and so on. Of course, a cr~cial element o~ all such systems is the velocity change sensor ;or accelerometer which initiates the inflation and deployment of the air bags. The motion of the motor vehicle must be carefully and precisely monitored so that th~ air bags can be deployed very fast, before the passengers suffer any substantial injury.
,- . .
. - . . .
., . , :. .. ~:. . -;
;
.
2 ~
A velocity change sensor is disclosed in U.S. Patent No.
~,329,54~ assigned to the same company as the present invention.
This sensor comprises a tubular housing surrounding a metallic shell, a metal ball and a magnet biasing the ball toward a first end of the shell. ~t the second end of the shell there are a pair of electrical contact blades. The sensor is positioned in the motor vehicle in an orientation such that when the motor vehicle experiences a deceleration which exceeds a present level, the ball moves from the first toward the second end, making contact with the two blades. Because the blades and the ball are made of an electrically conducting material, when the ball contacts the blades, an electrical path is established between the two blades.
This electrical path is used to initiate a signal for the deployment of the air bags.
; 15 Accuracy of the sensor described in U.S. Patent No.
4,329,549 depends on the proper alignment of the two electrical contact blades. The sensitivity, i.e. the minimal deceleration that sets off the sensor is determined by the strength of the magnet, and the initial position of the ball. It was found that because of variations in dimensions of the sensor during the manufacturing process, the sensor has a tolerance of about +2MPH.
In practice this tolerance is not acceptable in the industry because if the sensor triggers at deceleration which is too low, a restraint bag may be triggered when the car is not involved in a crash ~i.e. at 8 MPH) causing the driver to lose control over the motor vehicle. If the bag is set to trigger only when the vehicle experiences a very high deceleration (i.e. a crash at above 12 :
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MPH), it may not go off on actual crash, and would fail in its ~unction of protecting the passengers.
8U~MARY OF ~E INVENTION
In view of the above mentioned disadvantages of the prior art, it is an objective of the present invention to provide a ;restraint system in which the sensitivity time, i.e. the deceleration at which the bag restraint system i5 deployed can be preset to accurate value.
A further objective is to provide a restraint system with a velocity sensor in which a moving element has a presetable initial position for a reduced tolerance.
A further objective is to provide a sensor which is easy and inexpensiva to manufacture, and in which critical elements need not be made with high precision because the sensitivity of the sensor may be adjusted for each until after assembly.
`Other objectives and advantages of the invention shall become apparent from the following description. An accelerometer constructed in accordance with the invention includes a housing with contact blades and a contacting element which provides an electric path between the blades when a deceleration above a threshold level is sensed. An adjusting means is also provided for presetting th~ position of the element. Thls presetting adjusting means is adjusted after the assembly of the sensor to cooperate for diminished variations of its components as well as for variations ; 25 in the field strength of the magnet, if any. With this feature, it has been found that sensors can be made which can be adjusted to trlyger a section of the bag system in response to a crash of a given velocity, when said sensor may be present at an accuracy of t- 1 MPH.
` 5BRII~F DESCRIPTION OF T~IE DR~WINGS
These and other ob~ects and advantages of the invention will become apparent upon reading the following detailed description and upon referring to the drawings in which:
. FIGURE 1 shows a side elevation view of a first 10 accelerometer constructed in accordance with the invention disposed in a case;
FIGURE 2 shows in a side cross-sectional an alternate embodiment for the accelerometer of FIGURE l; and FIGURE 3 shows in a cross-sectional view, a second 15 accelerometer constructed in accordance with the invention.
While the invention will be described in conjunction with an example embodiment, it will be understood that it is not :intended to limit the invention to such embodiment. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
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ETAILED DEFIC~RIPTION OF q!~ll3 INVENTION
In the drawings, similar features have been given similar reference numerals.
The sensor shown in Figure 1 consists of a housing 12 with an interior chamber 14 holding a ball 16. The chamber 14 defines a movement path between a first end wall 24 and a second end wall 26 of chamber 14 for the ball 16 and a spring blade 18 is used to bias the ball and hold it in abutment with end wall 22, as shown in Figure 1. The sensor is positioned in a motor vehicle so that if the vehicle crashes as a preselected minimum speed, the ball, under the influence of the deceleration resulting from the crash, overcomes the biasing force of spring blade 18 and starts moving along the path defined by chamber 14 toward the opposite end wall 26. As the ball moves along its path, it pivots spring blade 18. When the spring blade 18 hits a second blade 20 an electric :contact is made which is used to generate an electric signal to a control means for triggering a passenger restraint system such as an air bag (not shown).
An important feature of the invention is the provision of preset screw 22 threaded and extending through the end wall 24 with its head 28 disposed outside the housing 12, and with its proximal end 30 being in contact with ball 16 in the rest position, as shown in Figure 1.
~The response of the sensor depends on a number of factors : 25 including the weight of the ball, the dimensions of the sensor, the spring constant of blade 1~ and so on. By varying these ,; . .~ l ,. . : , :
parameters, the sensor can be built to sense and respond to a present deceleration~ For example, -the parameters may be selected so that the sensor activates the passenger restraint system when a crash is sensed at a nominal speed of 10 MPH. ~Iowever, because of variat.~ons in these parameters which occur during the manufacturin~
process, the sensor has a characterist.ic error or tolerance of + 2 MPH. As previously mentioned this tolerance may be unacceptable.
However, it has been discovered that in a sensor constructed in accordance with this invention this tolerance ca~ be reduced considerably. More particularly, the rest position of the ball 16 may be adjusted with the preset screw 22. Advancing the screw causes the ball to move slightly away from end wall 24. Retrieving the screw from the housing causes the ball 16 to move slightly closer to the wall 24. In this manner the present velocity of the ~ 15 sensor, i.e. the velocity at which a crash will cause a sensor to activate a passenger restraint system may be preset with an accuracy or tolerance of ~ 1 MPH.
In the embodiment of Figure 1, the preset screw 22 is abutting dixectly ball 16 with end 30. In order to increase the contact area between the screw and the ball, a disk 32 may be attached to the screw end 30 as shown in Fiyure 2. In this manner the amount of wear and tear between the screw and the ball is reduced considerably. The disk is even more ef~ective if it is . attached rotatably to screw 22.
; 25 A different type of sensor 110 is shown in Fi~ure 3.
This sensor, similar to the sensor described in U.S. Patent No.
4,329,549, has a ho~sing 112 with an interior shell 114 made of '~
:: , -, - . . :. ~ :: .
: ; ' ~ ' :;
, . .
~ ' ' : . ,- ' ... ,:
2 ~ 2 ~
magnetically permeable material. ~he housing 11~ has to opposed end walls 124, 126. End wall 126 holds two blades 118, 120 which in this configuration have similar shapes and sizes. A permanent magnet 134 is disposed outside housing 112. Within the housing 112 there is also a ball 116 having a diameter slightlv smaller than shell 11~. I'he ball is also made of a magnetically permeable material. The shell 114, ball 116 and magnet 134 are constructed and arranged so that the magnetic field generated by the magnet biases the ball to the rest position shown in Figure 3. When the sensor is disposed in a motor vehicle in such a manner that, in a crash at a speed above a preselected level, ball moves toward wall 126. When it contacts blades 118, 120, an electrical signal is generated by well known means in the art. The signal is sent for example on wires 136, 138 to a passenger restraint system 140 for activating it. Again, without the preset screw 122, the sensor has a tolerance of about -~2 MPH. This tolerance is reduced to about ~1 ; MPH by adjusting screw 122 to move the ball 116 either toward or away from end wall 124.
- Obviously numerous modifications may he made to the invention without departing from its scope as defined in the appended claims.
Thus it is apparent that there has been provided in accordance with the invention that fully satisfies the objects, aims and advantages set forth above. While the invention has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing - ~:: .~ . , -, . ' : ' ' ,: . ~ ~ ,, :.
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description. Accordingly, it is intended to embrace all such alternatives, modiications and variations as fall within the spirit and broad scope of the invention.
, ~ , .
.
Claims (14)
1. An accelerometer for sensing velocity changes comprising:
a. a housing with a cavity for determining a path of movement;
b. an inertial element disposed in said housing and movable along said path between a first and a second position;
c. biasing means for biasing said inertial element toward one of said first position; and d. preset means disposed at said first end, said preset means being adjustable for changing said first position.
a. a housing with a cavity for determining a path of movement;
b. an inertial element disposed in said housing and movable along said path between a first and a second position;
c. biasing means for biasing said inertial element toward one of said first position; and d. preset means disposed at said first end, said preset means being adjustable for changing said first position.
2. The accelerometer of claim 1 wherein said biasing means comprises spring means.
3. The accelerometer of claim 1 wherein said inertial element is made of magnetic permeable material and said biasing means comprises magnet means for generating a magnetic field.
4. The accelerometer of claim 1 wherein said preset means comprises a preset screw extending from said housing into said path.
5. An accelerometer of activating a passenger restraint system in a motor vehicle, said accelerometer comprising:
a. a housing with an internal passage defining a path of movement;
b. an inertial element disposed in said housing for movement along said path;
c. biasing means for biasing said inertial element toward a first position;
d. preset means for defining said first position, said preset means being adjustable from outside said housing;
and e. contact means disposed on said path at second position at a predetermined distance from said first position, said contact means being arranged to sense when said inertial element has moved to said second position for activating said passenger restraint system.
a. a housing with an internal passage defining a path of movement;
b. an inertial element disposed in said housing for movement along said path;
c. biasing means for biasing said inertial element toward a first position;
d. preset means for defining said first position, said preset means being adjustable from outside said housing;
and e. contact means disposed on said path at second position at a predetermined distance from said first position, said contact means being arranged to sense when said inertial element has moved to said second position for activating said passenger restraint system.
6. The accelerometer of claim 5 wherein said inertial element comprises a ball.
7. The accelerometer of claim 6 wherein said housing includes a cylindrical sleeve having a diameter substantially equal to the diameter of the ball, and wherein said sleeve and said ball are made of magnetic permeable material.
8. The accelerometer of claim 7 wherein said biasing means comprises a permanent magnet arranged and constructed to generate magnetic field for biasing said ball.
9. The accelerometer of claim 5 wherein said biasing means comprises a spring.
10. A passenger restraint assembly for protecting passengers in a motor vehicle in a crash, said assembly comprising:
a. a passenger restraint system disposed in said motor vehicle; and b. an accelerometer disposed in said motor vehicle for activating said passenger restraint system, said accelerometer including:
(i) a housing with a passage defining a path;
(ii) an inertial element disposed in said housing for movement along said path; and (iii) preset means disposed at one end of said passage, said preset means being adjustable from outside the housing for defining a first position.
a. a passenger restraint system disposed in said motor vehicle; and b. an accelerometer disposed in said motor vehicle for activating said passenger restraint system, said accelerometer including:
(i) a housing with a passage defining a path;
(ii) an inertial element disposed in said housing for movement along said path; and (iii) preset means disposed at one end of said passage, said preset means being adjustable from outside the housing for defining a first position.
11. The passenger restraint assembly of claim 10 wherein said accelerometer further comprises (v) contact means disposed at a second position at a distance from said first position along said path, said contact means sensing when said inertial element has moved from said first position to said second position for producing a signal to said passenger restraint system.
12. The passenger restraint assembly of claim 10 wherein said preset means comprises screw means extending from through said housing.
13. The passenger restraint system of claim 10 wherein said biasing means comprises a spring for forcing said inertial element toward said first position.
14. The passenger restraint system of claim 10 wherein said biasing means comprises a magnet for generating a magnetic field for urging said inertial element toward said first position.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US41822889A | 1989-10-06 | 1989-10-06 | |
| US418,228 | 1989-10-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2026921A1 true CA2026921A1 (en) | 1991-04-07 |
Family
ID=23657229
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002026921A Abandoned CA2026921A1 (en) | 1989-10-06 | 1990-10-04 | Velocity change sensor with adjustment screw |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPH03134927A (en) |
| CA (1) | CA2026921A1 (en) |
| DE (1) | DE4031329A1 (en) |
| FR (1) | FR2652906A1 (en) |
| GB (1) | GB2236857A (en) |
| IT (1) | IT1241712B (en) |
| SE (1) | SE9001951L (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4218867A1 (en) * | 1991-06-11 | 1992-12-17 | Breed Automotive Tech | SPEED CHANGE SENSOR WITH A CYLINDRICAL MAGNET |
| FR2681695B1 (en) * | 1991-09-24 | 1997-01-10 | Breed Automotive Tech | SAFETY SPEED VARIATION DETECTOR. |
| DE4140691A1 (en) * | 1991-12-10 | 1993-06-17 | Trw Repa Gmbh | VEHICLE-SENSITIVE MECHANICAL CONTACTOR |
| DE4241784A1 (en) * | 1992-12-11 | 1994-06-16 | Teves Gmbh Alfred | Acceleration switch or sensor, esp. for vehicle braking system - has metal body displaceable under inertial force, and electrical position detector |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB779194A (en) * | 1954-03-01 | 1957-07-17 | Tiltman Langley Ltd | Improvements relating to impact detectors |
| GB877348A (en) * | 1958-10-16 | 1961-09-13 | Robertshaw Fulton Controls Co | Improvements in acceleration responsive device |
| US3452175A (en) * | 1967-05-29 | 1969-06-24 | Atomic Energy Commission | Roller-band devices |
| US3601081A (en) * | 1970-01-21 | 1971-08-24 | Ensign Bickford Co | Trigger mechanism for passenger-restraining safety device |
| GB1398121A (en) * | 1971-05-28 | 1975-06-18 | Nissan Motor | Impact responsive switch device and electric circuit using such device |
| FR2283444A1 (en) * | 1974-07-31 | 1976-03-26 | Sagem | Fluid filled acceleration detector - has mass held below threshold value in housing with detector at end |
| US4329549A (en) * | 1980-04-29 | 1982-05-11 | Breed Corporation | Magnetically biased velocity change sensor |
-
1990
- 1990-05-31 SE SE9001951A patent/SE9001951L/en not_active Application Discontinuation
- 1990-06-14 JP JP2156596A patent/JPH03134927A/en active Pending
- 1990-09-18 FR FR9011506A patent/FR2652906A1/en not_active Withdrawn
- 1990-10-02 IT IT67750A patent/IT1241712B/en active IP Right Grant
- 1990-10-04 CA CA002026921A patent/CA2026921A1/en not_active Abandoned
- 1990-10-04 DE DE4031329A patent/DE4031329A1/en not_active Withdrawn
- 1990-10-05 GB GB9021698A patent/GB2236857A/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| SE9001951L (en) | 1991-04-07 |
| IT9067750A1 (en) | 1992-04-02 |
| IT1241712B (en) | 1994-01-31 |
| GB2236857A (en) | 1991-04-17 |
| IT9067750A0 (en) | 1990-10-02 |
| JPH03134927A (en) | 1991-06-07 |
| GB9021698D0 (en) | 1990-11-21 |
| FR2652906A1 (en) | 1991-04-12 |
| DE4031329A1 (en) | 1991-04-11 |
| SE9001951D0 (en) | 1990-05-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |