AU2007234394B2 - Harness tension sensor and crash occurrence sensor - Google Patents

Harness tension sensor and crash occurrence sensor Download PDF

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Publication number
AU2007234394B2
AU2007234394B2 AU2007234394A AU2007234394A AU2007234394B2 AU 2007234394 B2 AU2007234394 B2 AU 2007234394B2 AU 2007234394 A AU2007234394 A AU 2007234394A AU 2007234394 A AU2007234394 A AU 2007234394A AU 2007234394 B2 AU2007234394 B2 AU 2007234394B2
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AU
Australia
Prior art keywords
seat
sensor
child safety
strap
safety device
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.)
Active
Application number
AU2007234394A
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AU2007234394A1 (en
Inventor
Said Nakhla
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Britax Child Safety Inc
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Britax Child Safety Inc
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Filing date
Publication date
Application filed by Britax Child Safety Inc filed Critical Britax Child Safety Inc
Publication of AU2007234394A1 publication Critical patent/AU2007234394A1/en
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Publication of AU2007234394B2 publication Critical patent/AU2007234394B2/en
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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60NSEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
    • B60N2/00Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
    • B60N2/24Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
    • B60N2/26Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles for children
    • B60N2/28Seats readily mountable on, and dismountable from, existing seats or other parts of the vehicle
    • B60N2/2803Adaptations for seat belts
    • B60N2/2812Adaptations for seat belts for securing the child to the child seat
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60RVEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R22/00Safety belts or body harnesses in vehicles
    • B60R22/48Control systems, alarms, or interlock systems, for the correct application of the belt or harness
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60NSEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
    • B60N2/00Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
    • B60N2/24Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
    • B60N2/26Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles for children
    • B60N2/28Seats readily mountable on, and dismountable from, existing seats or other parts of the vehicle
    • B60N2/2803Adaptations for seat belts
    • B60N2002/2815Adaptations for seat belts with additional belt accessories, e.g. a belt tension detector
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60RVEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R22/00Safety belts or body harnesses in vehicles
    • B60R22/48Control systems, alarms, or interlock systems, for the correct application of the belt or harness
    • B60R2022/4808Sensing means arrangements therefor
    • B60R2022/4841Sensing means arrangements therefor for sensing belt tension

Description

WO 2007/115301 PCT/US2007/065955 HARNESS TENSION SENSOR AND CRASH OCCURRENCE SENSOR TECHNICAL FIELD AND BACKGROUND OF THE INVENTION [0001] This invention relates to a harness tension sensor and related apparatus for a child safety seat. Child safety seats have a harness that includes a pair of shoulder straps that extend from the back rest of the seat across the shoulders of the seat occupant and a crotch strap that extends upwardly from the seat bottom to a point between the legs of the seat occupant. The shoulder straps extend downwardly and have latch members that interconnect with a latch affixed to the crotch strap that extends upwardly through a slot from below the seating surface. A tensioning strap extends through an opening in the front of the seating surface. When the shoulder straps are latched into the latch, the tensioning strap is pulled to place the shoulder straps in tension so that they fit securely against the anterior aspect of the upper torso of the seat occupant. Any significant slack in the shoulder straps can increase the risk of injury by subjecting the seat occupant to an initial rapid, unrestrained acceleration before the shoulder straps are tensioned by the forward movement of the seat occupant and bring the seat occupant to an almost instantaneous stop. [0002] At present, child safety seats do not incorporate a reliable means to determine whether the shoulder straps have been properly tensioned. Some proposals for placing tension sensors in the latch or elsewhere require wiring in the crotch strap or in other locations in the seating area. This wiring may be subject to wear or exposure to moisture during use or cleaning, and thus may be less than fully desirable for use in situations, such as child safety seats, that should be cleaned periodically, or are subject to wetting from spilled drinks or other liquids. 1 of 12 WO 2007/115301 PCT/US2007/065955 [0003] Also, it may not be fully apparent in all cases that the shoulder straps have not been fully latched. Thus, inadequate tension on the shoulder straps may be the result of simple failure to sufficiently tighten the shoulder straps, or because the shoulder straps have not been properly latched. In the case of improper latching, the seat occupant is essentially unprotected in the event of an impact, since the latch members will exit the latch and prevent any significant tension at all on the straps during the initial phase of the impact. [0004] In addition, present child safety seats to not provide a positive means of indicating that the seat has been subjected to a load of sufficient severity to require that the seat not be further used. A severe impact may stretch the shoulder straps beyond their elastic limit, warp or damage plastic seat parts, or otherwise render the seat unsafe for further use. In many cases the damage will not be readily visible and, in any event, it may not be apparent to the user that the damage is severe enough to require seat replacement. SUMMARY OF THE INVENTION [0005] Therefore, it is an object of the invention to provide a harness tension sensor and related apparatus for a child safety seat. [0006] It is another object to provide a child safety seat that has a sensor that detects both that the seat is properly latched and that the shoulder straps have been properly tensioned. [0007] It is another object to provide a child safety seat that has a sensor that detects that the seat is properly latched and that the shoulder straps have been properly tensioned, wherein the operative elements of the sensor and related parts 2 of 12 WO 2007/115301 PCT/US2007/065955 are under the seat and away from wear and liquids. [0008] It is another object to provide a child safety seat that has a sensor that detects that the seat has been subjected to a load of sufficient severity that further use of the seat should not be permitted. [0009] These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing a child safety device for a vehicle including a seat including a shell, a harness including at least one strap for retaining an occupant in the seat, and a sensor between a device on the strap and the seat shell for indicating whether the harness is sufficiently tensioned. [0010] According to another preferred embodiment of the invention, the harness includes shoulder straps and a crotch strap. [0011] According to another preferred embodiment of the invention, the device on the strap includes a strap buckle or slide. [0012] According to another preferred embodiment of the invention, the sensor is positioned on a shell bottom. [0013] According to another preferred embodiment of the invention, a child safety device for a vehicle includes a seat including a shell, a harness including at least one strap for retaining an occupant in the seat, and a sensor including crushable members between a device on the strap and the seat shell for indicating whether the harness has been severely tensioned. [0014] According to another preferred embodiment of the invention, the crushable members are calibrated to crush at 500-700 pounds of load. [0015] According to another preferred embodiment of the invention, the crushable members comprise ribs or thin walls. 3 of 12 WO 2007/115301 PCT/US2007/065955 [0016] According to another preferred embodiment of the invention, the sensor is a one use, one way type. [0017] According to another preferred embodiment of the invention, a child safety device for a vehicle includes a seat including a shell and a harness including a strap for retaining an occupant in the seat. The device further includes a sensor between a device on the strap and the seat shell for indicating whether the harness is sufficiently tensioned, and a sensor including crushable members between the device on the strap and the seat shell for indicating whether the harness has been severely tensioned. [00181 According to another preferred embodiment of the invention, both sensors are positioned under the seat shell. BRIEF DESCRIPTION OF THE DRAWINGS [0019] Embodiments of the invention may be best understood by reference to the following description in conjunction with the accompanying drawing figures in which: [0020] Figure 1 is front perspective view of an embodiment of a child safety seat; [0021] Figure 2 is side view of the embodiment of the child safety seat; [0022] Figure 3 is an enlarged view of an embodiment of a crash occurrence assembly for the child safety seat; [0023] Figure 4 is a top view of an embodiment of a sensor housing; [0024] Figure 5 is a side view of the sensor housing of Figure 4 showing crash occurrence and belt tension sensors; 4 of 12 WO 2007/115301 PCT/US2007/065955 [0025] Figure 6 is an enlarged side view of an embodiment of a belt tension sensor in a closed state; [0026] Figure 7 is an enlarged side view of an embodiment of a crash occurrence sensor in an open state; [0027] Figure 8 is a side view of the crash occurrence sensor of Figure 7 in the closed state; [0028] Figure 9 is an enlarged side view of an embodiment of a belt tension sensor in an open state; [0029] Figure 10 is a side view of the belt tension sensor of Figure 9 in the closed state; [0030] Figure 11 is an enlarged side view of an embodiment of a combined belt tension and crash occurrence sensor showing the belt tension sensor in a closed state; and [0031] Figure 12 is a side view of the embodiment of Figure 11 showing the crash occurrence sensor in a closed state. DESCRIPTION OF PREFERRED EMBODIMENTS [0032] Figures 1-3 show a child safety seat 12 and harness 20 including a pair of shoulder straps 23 and 25 for insertion into a buckle 22 fixed to a crotch strap 26 that passes through a slot 29 in a seat shell 14 and is fixed at a distal end to a three bar slide 27. A sensor housing 18 is positioned between the seat shell 14 and the three bar slide 24. Tension Sensor 5 of 12 WO 2007/115301 PCT/US2007/065955 [0033] As shown in Figures 1-6 and 9-11, the tension sensor 10 is designed to insure that sufficient tension is present in a harness 20 for a child safety seat 12. The sensor 10 may be associated with a buckle 22 or three bar slide 24 that captures one end of the crotch strap 26. The buckle 22 or three bar slide 24 is sufficiently large to retain the crotch strap 26 in the correct position between the legs of the seat occupant by bearing against the underside or bottom of the plastic seat bottom shell 14 with the strap 26 itself extending through the slot 29 and into the crotch area of the seat occupant. [0034] In one embodiment shown in Figures 1-3, the sensor 10 sits between the crotch strap buckle 22, or, a three-bar slide 24, and the plastic seat bottom shell 14. When sufficient tension is on the harness 20, the crotch strap 26 or three bar slide 24 is pulled upwardly thorough the slot 29 in the seat 12 bottom, and the buckle 22 or three bar slide 24 presses the sensor 10 against the seat bottom shell 14. [0035] in one embodiment, a plunger 42 or other mechanism urges the sensor 10 from a normally open position to a closed position when there is too little tension on the harness 20. Closing the circuit allows a current to flow to a device such as a microprocessor that can activate any conventional alert means, such as a bell, buzzer, light, etc. that the harness needs to be further tightened. Latching the harness correctly and/or further tightening the harness 20 opens the circuit and deactivates the alert. [0036] Conversely, the circuit can be designed so that the circuit is normally closed when the tension is correct, as shown in Figures 6 and 10, and in the open condition when the tension must be increased, as shown in Figures 5 and 9. The 6 of 12 WO 2007/115301 PCT/US2007/065955 open circuit is sensed and a microprocessor generates the alert, as described above. [0037] The sensor may be any suitable pressure-sensitive on-off type switch, for example, spring-loaded contacts 13 that engage a complementary contact 15 in order to close the circuit, as shown in Figures 5 and 9-12. Crash Occurrence Sensor [0038] As shown in Figures 1-5, 7-8 and 11-12, in another aspect of the invention, the child safety seat 12 has a sensor 11 that detects that the seat 12 has been subjected to a load of sufficient severity that further use of the seat 12 should not be permitted. This crash occurrence sensor 11 may be used together with or separate from the tension sensor 10 described above. Figure 11 shows an embodiment of the invention wherein a plunger 42 indicates first that belt tension is sufficient and also indicates when the harness 20 has been subjected to a mor severe load. [0039] In general, the crash occurrence sensor 11 is a "one use, one way" sensor. When it detects a severe load on a single occasion, it closes a circuit that provides an alert that the seat 12 has potentially been subjected to sufficient damage that the seat 12 should be discarded and not further used. The circuit is designed not to return to a normal state. [0040] More specifically, the crash occurrence sensor 110 includes crushable members 77 that are calibrated to crush at, for example, 500-700 lbs. of load. Crushing of the crushable members 77, as shown in Figures 8 and 12, closes a circuit. The crushable members 77 may be ribs, thin walls, foam or honeycomb 7 of 12 materials, or any other suitable material that has the ability to resist crushing up to a predetermined point, and then reliably crush to a degree sufficient to close a circuit. As also shown in the attached drawings, the crushable members 77 may be positioned on an upper surface of the crotch strap buckle 22, or a three-bar slide 24, so that in the event of a severe load, 5 the buckle 22 or slide 24 is pulled upwardly against the plastic shell 14 of the seat by the crotch strap 26 so severely that the crushable members 77 are crushed against the plastic shell 14, engaging the contact 17 and 19 to close a circuit. With less severe loads, the crushable members 77 do not crush to any appreciable degree. As is apparent from the foregoing, all of the electronic features of both the tension sensor 10 0 and the crash occurrence sensor I I may be placed under the seat shell 14 away from the seat occupant and possible wear and damage. Throughout the specification and the claims that follow, unless the context requires otherwise, the words "comprise" and "include" and variations such as "comprising" and "including" will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any 5 other integer or group of integers. The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge. It will be appreciated by those skilled in the art that the invention is not restricted in its use to 0 the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that various modifications can be made without departing from the principles of the invention. Therefore, the invention should be understood to include all such modifications in its scope. 25

Claims (13)

  1. 3. The child safety device according to either of the preceding claims, wherein the seat comprises a shell and wherein the sensor is positioned on a shell bottom. 5
  2. 4. A child safety device for a vehicle, comprising: (a) a seat; (b) a harness comprising at least one strap for retaining an occupant in the seat; and (c) a sensor located between the at least one strap and the seat, wherein increasing the 0 tension in the at least one strap exerts a force on the seat, and wherein the sensor indicates when the force exerted on the seat is severe.
  3. 5. The child safety device according to claim 4 wherein the sensor is a one use, one way type. 25 6. The child safety device according to any one of the preceding claims, wherein the sensor indicates when the degree of the force exerted on the seat corresponds to sufficient tension in the at least one strap.
  4. 7. The child safety device according to any one of the preceding claims, wherein the sensor 30 activates an alert means when the degree of the force exerted on the seat corresponds to sufficient tension in the at least one strap.
  5. 8. The child safety device according to any one of the preceding claims, wherein the sensor comprises a spring that contracts when the force is exerted on the seat. 35
  6. 9. The child safety device according to claim 8, wherein the sensor indicates when the spring becomes a length that corresponds to sufficient tension in the at least one strap. n
  7. 10. The child safety seat according to any one of the preceding claims further comprising a device located between the at least one strap and sensor such that when the tension in the at least one strap increases the device exerts a force on the seat. 5 11. The child safety seat according to claim 10, wherein the device comprises a strap buckle or slide.
  8. 12. The child safety device according to any one of the preceding claims further comprising a second sensor located between the at least one strap and the seat, wherein increasing the tension in the 0 at least one strap exerts a force on the seat, and wherein the second sensor indicates when the force exerted on the seat is severe.
  9. 13. The child safety device according to claim 12, wherein the seat comprises a shell and wherein both sensors are positioned on the shell bottom. 5
  10. 14. The child safety device according to claim 4, wherein the sensor comprises at least one crushable member that is configured to crush when the force exerted on the seat is severe, and wherein the sensor indicates when the at least one crushable member is crushed. 0 15. The child safety device according to claim 4, wherein the sensor activates an alert means when the sensor indicates that the force exerted on the seat is severe.
  11. 16. The child safety device according to claim 14, wherein the crushable members are calibrated to crush at 500-700 pounds of load. 25
  12. 17. The child safety device according to either of claims 14 or 16, wherein the crushable members comprise ribs or thin walls.
  13. 18. A child safety device being as described in the specification with reference to and as 30 illustrated in the accompanying drawings. 1in
AU2007234394A 2006-04-04 2007-04-04 Harness tension sensor and crash occurrence sensor Active AU2007234394B2 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US74423906P 2006-04-04 2006-04-04
US60/744,239 2006-04-04
US11/695,947 2007-04-03
US11/695,947 US20070228802A1 (en) 2006-04-04 2007-04-03 Harness tension sensor and crash occurrence sensor
PCT/US2007/065955 WO2007115301A2 (en) 2006-04-04 2007-04-04 Harness tension sensor and crash occurrence sensor

Publications (2)

Publication Number Publication Date
AU2007234394A1 AU2007234394A1 (en) 2007-10-11
AU2007234394B2 true AU2007234394B2 (en) 2010-10-28

Family

ID=38557743

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2007234394A Active AU2007234394B2 (en) 2006-04-04 2007-04-04 Harness tension sensor and crash occurrence sensor

Country Status (4)

Country Link
US (1) US20070228802A1 (en)
AU (1) AU2007234394B2 (en)
CA (1) CA2647207A1 (en)
WO (1) WO2007115301A2 (en)

Families Citing this family (14)

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US8500196B2 (en) * 2008-04-15 2013-08-06 Britax Child Safety, Inc. Child seat having a crush zone
FR2939383B1 (en) * 2008-12-04 2011-05-06 Dorel France Sa MOTOR SEAT FOR A CHILD WITH A VISUAL HARNESS CLAMP INDICATOR, AND CORRESPONDING VISUAL INDICATOR
IT1395653B1 (en) * 2009-08-04 2012-10-16 Sabelt Spa SAFETY BELT FOR A CHILD SEAT SEAT
WO2012037412A2 (en) * 2010-09-15 2012-03-22 Amsafe Commercial Products, Inc. Occupant restraint system components having status indicators and/or media interfaces, and associated methods of use and manufacture
GB2495843B (en) * 2011-10-21 2014-12-03 Bp Childrens Prod Hk Co Ltd Child safety seat having an adjustable crotch strap
FR3008936B1 (en) * 2013-07-25 2016-12-23 Dorel France Sa CHILDREN'S CAR SEAT, INTENDED TO BE SOLIDARIZED AT THE SEAT OF A MOTOR VEHICLE
FR3021276B1 (en) * 2014-05-23 2017-09-29 Naxio SAFETY DEVICE FOR CHILD SEAT WITH MONITORING THE POSITION OF A STRAP FOR THE SEAT
US10239487B2 (en) 2015-02-12 2019-03-26 Bluebeep Sensor device and device for checking the operational condition of a harness of a safety seat
US9781977B2 (en) 2015-08-11 2017-10-10 Shield Restraint Systems, Inc. Interlocking web connectors for occupant restraint systems and associated methods of use and manufacture
EP3421958A4 (en) * 2016-02-23 2019-03-13 Achiseiki Co., Ltd. Load fastening member loosening detection device, and load fastening member loosening detection system
WO2018053348A1 (en) 2016-09-16 2018-03-22 Shield Restraint Systems, Inc. Buckle assemblies and associated systems and methods for use with child seats and other restraint systems
US10457246B2 (en) * 2017-04-12 2019-10-29 Dorel Juvenile Group, Inc. Child restraint system for juvenile vehicle seat
CN207140871U (en) * 2017-07-21 2018-03-27 宁波宝贝第一母婴用品有限公司 A kind of upper drawstring tenses detecting system and child safety seat
US11124152B2 (en) 2018-11-20 2021-09-21 Shield Restraint Systems, Inc. Buckle assemblies for use with child seats and other personal restraint systems

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US5711574A (en) * 1993-07-16 1998-01-27 New Lenox Industries, Inc. Air bag-equipped child's vehicle seat and alarm/arming system therefore
US6623032B2 (en) * 2000-01-24 2003-09-23 Siemens Vdo Automotive Corporation Belt force sensor
US20040232747A1 (en) * 2001-08-22 2004-11-25 Kojiro Yamazaki Child seat

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DE2811199A1 (en) * 1978-03-15 1979-09-20 Klippan Nv DEVICE FOR THE LOAD INDICATOR OF A HOLDING DEVICE THAT CAN BE SUBMITTED UNDER TENSION
US6301977B1 (en) * 2000-05-02 2001-10-16 Stojan Stojanovski Vehicle seat belt transducer for child's seat
JP4507463B2 (en) * 2001-06-15 2010-07-21 株式会社デンソー Seat belt tension detection device

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Publication number Priority date Publication date Assignee Title
US5711574A (en) * 1993-07-16 1998-01-27 New Lenox Industries, Inc. Air bag-equipped child's vehicle seat and alarm/arming system therefore
US6623032B2 (en) * 2000-01-24 2003-09-23 Siemens Vdo Automotive Corporation Belt force sensor
US20040232747A1 (en) * 2001-08-22 2004-11-25 Kojiro Yamazaki Child seat

Also Published As

Publication number Publication date
US20070228802A1 (en) 2007-10-04
CA2647207A1 (en) 2007-10-11
WO2007115301A3 (en) 2008-03-27
WO2007115301A2 (en) 2007-10-11
AU2007234394A1 (en) 2007-10-11

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