Restraint system for an occupant seat mounted in a motor vehicle

A restraint system for an occupant seat mounted in a motor vehicle includes a processor to produce at least one control signal to control either or both of an electronically controllable unit to disable or impede operation of the motor vehicle and a notification device to produce a notification unless, in sequence, a first sensor produces a first signal indicating detection of an occupant being seated in the occupant seat followed by at least one second sensor producing least one second signal indicating that a rotatable shaft of a web retractor coupled to a web of a restraint harness has rotated by at least a threshold amount followed by a third sensor producing a third signal indicating that a tongue of the restraint system is engaged with a buckle of the restraint system.

FIELD OF THE INVENTION

The present invention relates generally to restraint systems for motor vehicles, and more specifically to restraint systems in which occupant operation of the restraint system operation is monitored and automatically acted upon.

BACKGROUND

Occupant restraint systems for motor vehicles may include one or more electronic sensors and/or electronically controlled units or actuators and/or electronically controlled indicators. It is desirable to monitor occupant operation of some such restraint systems and to control one or more electronically controlled units or actuators and/or one or more notification devices based thereon.

SUMMARY

The present disclosure may comprise one or more of the features recited in the attached claims, and/or one or more of the following features and combinations thereof. In one aspect, a restraint system for an occupant seat mounted in a motor vehicle may comprise a restraint harness having at least one web, a web retractor configured to be mounted to the occupant seat or a support surface to which the occupant seat is mounted within the motor vehicle, the web retractor having a rotatable shaft about which the at least one web is wound when retracting into the web retractor and from which the at least one web is unwound when being paid out of the web retractor, one of a tongue or buckle coupled to the at least one web, the other of the tongue or buckle configured to be mounted to one of the occupant seat or a support surface to which the occupant seat is mounted within the motor vehicle, the tongue and the buckle configured to releasably engage one another to restrain an occupant in the occupant seat with the restraint harness, a first sensor configured to produce a first signal corresponding to detection of an occupant being seated in the occupant seat, at least one second sensor operatively coupled to the web retractor and configured to produce at least one second signal corresponding to rotation of the rotatable shaft, a third sensor configured to produce a third signal corresponding to detection of engagement of the tongue with the buckle, and a processor including a memory having instructions stored therein which, when executed by the processor, cause the processor to produce at least one control signal configured to control at least one of an electronically controllable unit to disable or impede operation of the motor vehicle and a notification device to produce a notification unless, in sequence, the first sensor produces the first signal followed by the at least one second signal produced by the at least one second sensor indicating that the rotatable shaft of the web retractor has rotated by at least a threshold amount followed by the third sensor producing the third signal.

DETAILED DESCRIPTION OF THE DRAWINGS

References in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases may or may not necessarily refer to the same embodiment. Further, when a particular feature, structure or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure or characteristic in connection with other embodiments whether or not explicitly described. Further still, it is contemplated that any single feature, structure or characteristic disclosed herein may be combined with any one or more other disclosed feature, structure or characteristic, whether or not explicitly described, and that no limitations on the types and/or number of such combinations should therefore be inferred.

It will be understood that, for purposes of this disclosure, all phrases recited in the attached claims in the general form “at least one of A and B” are intended to be interpreted as only A, only B or a combination of A and B.

Referring now toFIG. 1, an embodiment is shown of restraint system10for an occupant seat12mounted in a motor vehicle. In the illustrated embodiment, the occupant seat12, has a seat bottom12A configured to support an occupant of the seat12and a seat back12B extending upwardly from the seat bottom12A. In the illustrated embodiment, the occupant seat12is mounted to a floor F of the motor vehicle, although in alternate embodiments the occupant seat12may be mounted to one or more other structures of the motor vehicle or to a combination of the floor F and one or more other structures of the motor vehicle, in any conventional manner. The restraint system10illustratively includes a restraint harness15for restraining an occupant seated on the occupant seat12. In the illustrated embodiment, the restraint harness15includes a single web16extendable from a retractor14of the restraint system10. A buckle (or tongue)20configured to releasably engage a complementarily configured tongue (or buckle)18attached to the free end of the web16. The restraint system10further includes a number of sensors S1, S2, S3and a processor22including a memory24. In some embodiments, the one or more electronically controlled units26may be carried by or mounted to or within the motor vehicle and electrically connected to the processor22, and in some such embodiments one or more such units26may be coupled to one or more devices, systems or actuators28. In some embodiments, one or more notification devices30may be carried by or mounted to or within the motor vehicle and electrically connected to the processor22. In some embodiments, the restraint system10may include one or more remote notification devices34, and in such embodiments the processor22may include, or be electrically connected to, a communication circuit32configured to communicate wirelessly with the one or more remote notification devices34.

In the embodiment illustrated inFIG. 1, the restraint harness15is depicted as including only a single web16, e.g., in the form of a conventional 2-point lap web restraint in which the retractor14and the tongue/buckle18/20serve as the two restraint points, although it will be understood that the restraint system10may alternatively be implemented in applications in which the restraint harness15has additional points of restraint. Examples of such alternate restraint harnesses15include, but are not limited to, a conventional 3-point restraint harness including a unitary or two-web shoulder and lap restraint, a conventional 4-point restraint harness including two unitary or two-web shoulder and lap restraints, a conventional 5-point restraint harness including two unitary or two-web shoulder and lap restraints and a crotch restraint and a conventional 6-point restraint harness including two unitary or two-web shoulder and lap restraints and two thigh-restraints. In any such alternate restraint system(s), it will be understood that one or more sensors S2may be implemented in one or more retractors in embodiments which include multiple retractors and/or that one or more sensors S3may be implemented in one or more buckles (and/or tongues) in embodiments which include multiple buckles and/or tongues.

In the embodiment illustrated inFIG. 1, the retractor14is depicted as being mounted to one side of the vehicle seat12. In alternate embodiments, the retractor14may be mounted to the floor F or other structure within the motor vehicle (e.g., to a post, pillar, frame or other support structure of or within the motor vehicle). In the illustrated embodiment, the buckle20is illustratively secured, e.g., via a conventional anchor, to the opposite side of the seat12, although in other embodiments the buckle20may instead be secured to the floor F or other support structure within the motor vehicle. In still other embodiments, the positions of the retractor14and the buckle20relative to the seat12may be swapped.

As is conventional, the retractor14illustratively has a rotatable shaft about which the web16is wound when retracting into the retractor and from which the web16is unwound when being paid out of the retractor14. In some embodiments, the retractor may illustratively include a conventional spool that is rotatable with the shaft and to which one end of the web16is attached, although in other embodiments the one end of the web may be attached directly to the rotatable shaft. In any case, the retractor14further illustratively includes a conventional biasing member, e.g., spring, which biases the rotatable shaft (and/or spool) in a web take-up direction, i.e., so that the web16retracts within the retractor14, and the biasing force such a biasing member is illustratively selected so as to be overcome by manually pulling the web16away from the retractor14such that the rotatable shaft rotates in a web payout direction as the web16is paid out of the retractor14.

The sensor S1is illustratively located on, in or adjacent to the seat bottom12A and/or seat back12B of the occupant seat12, and is configured to produce a signal corresponding to detection of an occupant being seated in the seat12. In one embodiment, the sensor S1is illustratively provided in the form of a conventional pressure sensor mounted on or within the seat bottom12A and configured to produce a pressure signal corresponding to an amount of downward pressure acting on the seat bottom12A. In such embodiments, the memory24illustratively has a pressure threshold value stored therein, and further has instructions stored therein which, when executed by the processor22, cause the processor22to monitor the pressure signal and determine that an occupant has been seated in the seat12if a downward pressure greater than a threshold pressure is acting on the seat bottom12A as indicated by the pressure signal corresponding to a pressure value that is greater than the pressure threshold value stored in the memory24. In alternate embodiments, the sensor S1may illustratively be provided in the form of a conventional pressure switch that is calibrated produce an activation signal if the downward pressure acting on the seat bottom12A exceeds a threshold pressure. In such embodiments, the instructions stored in the memory24include instructions which, when executed by the processor22, cause the processor22to monitor the pressure switch S1and determine that a downward pressure greater than the threshold pressure is acting on the seat bottom12A if the pressure switch S1produces the activation signal. In still other embodiments, the sensor S1may be provided in the form of one or more proximity sensors and/or switches or other conventional sensor(s) configured to produce a signal upon detection of the occupant being seated in the occupant seat12or configured to produce a signal from which the processor22may determine if/when the occupant12has been seated in the occupant seat12.

The sensor S2is illustratively provided in the form of at least one sensor or switch operatively coupled to or mounted within the retractor14and configured to, in a broad sense, monitor movement of the web16relative to the web retractor14, i.e., as the web16is paid out of and/or retracted within the retractor14, and to produce a signal corresponding to such movement of the web16relative to the retractor14. Example embodiments of the at least one sensor S2mounted within the retractor14are illustrated inFIGS. 2A-11and will be described in detail below. In any such embodiments, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor S2and determine from the signal(s) produced thereby whether a threshold length of the web16is paid out of the web retractor14.

The sensor S3is illustratively provided in the form of a conventional latch sensor or switch mounted to or within the buckle20. In alternate embodiments, the sensor S3may be provided in the form of a proximity sensor or other sensor configured to discriminate between latched and unlatched states of the tongue18and buckle20. In any case, S3is illustratively operable to produce a latch signal when the tongue18and the buckle20engage each other, i.e., are releasably engaged with each other. The instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the S3and determine that the tongue18and buckle20are engaged with one another if/when the S3produces the latch signal.

The sensor/switch signals S1, S2and S3are illustratively provided as inputs I1, I2and I3respectively to the processor22, and the memory24is illustratively programmed with instructions which, when executed by the processor22, cause the processor22to produce either or both of the control signal(s) OUT1and/or OUT2as a function of I1, I2and I3. As illustrated inFIG. 1, the motor vehicle may include any number, N, of electronically controlled units26electrically connected to the output OUT1of the processor22or otherwise communicatively coupled to the processor22(e.g., via wireless communication circuits), where N may be any positive integer. As further illustrated inFIG. 1, one or more such units26may be coupled, e.g., mechanically, hydraulically, pneumatically and/or electrically, to one or more devices, systems and/or actuators28. Non-limiting examples of some such units26and systems, devices and/or actuators28will be described below. As further illustrated inFIG. 1, the restraint system10may include any number, M, of notification devices30electrically connected to the output OUT2of the processor22, and non-limiting examples of some such notification devices will be described below, wherein M may be any positive integer. Alternatively or additionally, at least one remote notification device34may be provided and configured for wireless communications with the processor22. In such embodiments, the processor22illustratively includes or is electrically connected to a wireless communication circuit32configured to communicate wirelessly with the at least one remote notification device34. Non-limiting examples of the at least one remote notification device34will be described below.

In embodiments that include one or more electronically controlled units26, such one or more electronically controlled units26may be or include any one or more conventional, electronically controllable units, systems, actuators or the like which may be controlled by the processor22and which, when controlled, affects operation of the motor vehicle itself, e.g., the ability of the motor vehicle to move, or operation of a driven or actuated component of the motor vehicle. Examples of the one or more electronically controlled units26may include, but are not limited to, a conventional fuel system operatively coupled to a conventional engine of the motor vehicle, a conventional ignition system operatively coupled to a conventional engine of the motor vehicle, a conventional electronically controlled transmission coupled to a conventional engine of the motor vehicle, a conventional electronically controlled hydraulic actuator operatively coupled to the motor vehicle and to one or more hydraulically actuated components carried by or separate from the motor vehicle, a conventional electronically controlled pneumatic actuator operatively coupled to the motor vehicle and to one or more pneumatically actuated components carried by or separate from the motor vehicle and a conventional power takeoff (PTO) unit operatively coupled to or otherwise driven by a conventional engine or transmission of the motor vehicle and to one or more PTO-driven components carried by or separate from the motor vehicle. Examples of the one or more systems, devices and/or actuators28may include, but are not limited to, a conventional accelerator pedal or similar fueling control mechanism manually movable in a conventional manner between idle and full-throttle positions, a conventional keyed on non-keyed ignition starting switch, a conventional manually-actuated transmission shifting control lever, one or more conventional hydraulically-actuated components such as lift arms, one or more buckets, a backhoe, pallet forks, an angle broom, a sweeper, an auger, a mower, a snow blower, a stump grinder, a tree spade, a trencher, a dumping a hopper, a tiller, a ripper, a grapple, a tilt, a roller, a snow blade, a wheel saw, a cement mixer, a wood chipper, a hydraulic breaker, or the like, one or more conventional pneumatically-actuated components such as any of the preceding example components, and one or more conventional PTO-driven components such as any of the preceding example components, a water pump on a fire truck or water truck, floor cleaning machinery, a blower system, a vehicle bed raising mechanism, a winch, a trash compactor, a boom and/or a grapple, or the like.

In embodiments that include one or more notification devices30, such one or more notification devices may be or include any conventional visible, audible and/or tactile device mounted to or within the motor vehicle. In embodiments that include one or more remote notification devices34, such one or more remote notification devices34may be or include any conventional visible, audible and/or tactile device located remotely from the motor vehicle. It is to be understood that, in some embodiments, one or more remote notification devices34may be alternatively implemented in the form of a mobile or desktop electronic device such as a computer, mobile phone, tablet computer, or the like, and in such embodiments the processor22may be operable to control the communication circuit32to wirelessly transmit one or more messages to the one or more remote notification devices34, e.g., via conventional short-range wireless communication hardware and communication protocol such as Bluetooth® or other short-range technology, or via conventional long-range wireless communication hardware and communication protocol such as the Internet. As an example of the latter, the processor22may be configured, i.e., programmed, to wirelessly transmit a message, report or other indicator relating to the sequential states or statuses of the sensors S1, S2, S3, as described below, to a remote notification device34, e.g., via email, text messaging, or the like for viewing by a supervisor or employer of an operator/occupant of the motor vehicle, by a monitoring service hired by an employer of the operator/occupant of the motor vehicle and/or by one or more other persons. As another example, the processor22may be configured, i.e., programmed, to wirelessly transmit a message, report or other indicator relating to the sequential states or statuses of the sensors S1, S2, S3as described below to a secure website or web-based service accessible by one or more remote notification devices34for viewing by a supervisor or employer of an operator/occupant of the motor vehicle, by a monitoring service hired by an employer of the operator/occupant of the motor vehicle or by one or more other persons.

In one embodiment, the OUT1and/or OUT2signal is illustratively normally inactive, and will remain so only if signals are sequentially produced, in order, by S1, S2and S3to indicate that (1) the occupant/operator is first seated in the occupant seat12, (2) a threshold length of the web16is thereafter drawn from the retractor14, and (3) the tongue18is then latched to the buckle20. In one embodiment in which S1is provided in the form of a pressure sensor or switch and S3is provided in the form of a latch sensor or switch, S1, S2and S3are monitored by the processor22pursuant to instructions stored in the memory24which, when executed by the processor22, cause the processor22to produce the OUT1and/or OUT2control signal(s) to control the electronically controlled unit26and/or activate the one or more notification devices30, and/or to control the communication circuit32to wirelessly activate or transmit a message to the one or more remote notification devices34unless, in order, the signal produced by S1indicates that a downward pressure greater than a threshold pressure is acting on the seat bottom12A from the top surface thereof, followed by the signal produced by S2indicating that a threshold length of the web16is paid out of the web retractor14followed by the signal produced by S3indicating that the tongue18and buckle20are engaged with one another. If such signals are produced by S1, S2and S3in any other order, and/or if one or more of the sensors S1, S2, S3fails to produce the corresponding signal in a timely manner, the processor22produces the OUT1and/or OUT2control signal(s) to control the electronically controlled unit26and/or activate the one or more notification devices30, and/or to control the communication circuit32to wirelessly activate or transmit a message to the one or more remote notification devices34.

In some embodiments, the motor vehicle and/or the restraint system10includes only the notification device30or the one or more remote notification devices34, and in such embodiments production by the processor22of the OUT2signal activates the notification device30to notify the occupant that the above-described events do not occur in the required sequence and/or control of the communication circuit32by the processor22operates to notify another person or device of the same. In some embodiments, the occurrence of production of the OUT2signal and/or of the message sent by the communication circuit32is stored, and optionally date stamped, in the memory24. In other embodiments, the processor22illustratively produces only the OUT1control signal to cause the motor vehicle to be partially or wholly inoperable. In other still embodiments, the processor22may produce any combination of the OUT1control signal, the OUT2control signal and the one or more wireless communication signals.

In embodiments in which the processor22is operable to produce the OUT1control signal if/when the signals from the sensors S1, S2, S3are not each timely received in order as described above, the processor22is illustratively configured, i.e., programmed, to control the signal produced at OUT1in a manner which disables or impedes operation of the motor vehicle. It will be understood that the phrase “disables or impedes operation of the motor vehicle,” as used in this disclosure, is intended to encompass operation of the motor vehicle itself, e.g., movement of the motor vehicle in any direction, as well as operation of any component of the motor vehicle, e.g., including an engine of the motor vehicle and/or any component actuated, driven or otherwise controlled by the engine and/or any component actuated, driven or otherwise controlled by an actuating device or system onboard the motor vehicle. In this regard, control by the processor22of the signal produced at OUT1will generally be dependent upon the structural implementation of the electronically controlled unit26and, in embodiments that include it/them, the structural implementation of the system(s), device(s) or actuator(s)28coupled thereto.

As one non-limiting example, the electronically controlled unit26may be a motor vehicle fuel system operatively coupled to the engine of the motor vehicle and the device(s)/actuator(s)28may be an accelerator pedal movable between idle and full throttle positions. In this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively controls the fuel system26to limit fueling to the engine in a manner that limits the rotational speed of the engine to an idle speed regardless of the position or movement of the accelerator pedal so as to prevent the occupant/operator from moving the vehicle at speeds greater than that attainable at the engine idle speed.

As another non-limiting example, the electronically controlled unit26may be a motor vehicle ignition system operatively coupled to the engine of the motor vehicle and the device(s)/actuator(s)28may be a keyed or non-keyed ignition switch. In this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively disables the ignition system26so that the engine will not start regardless of the position or activation of the ignition switch so as to prevent the occupant/operator from starting the engine. In one variant of this example in which the engine is running when the signals from the sensors S1, S2, S3are processed, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively controls the ignition system26to shut down, i.e., turn off, the engine.

As a further non-limiting example, the electronically controlled unit26may be an electronically controllable transmission operatively coupled to the engine of the motor vehicle. In this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively disables electronically-controlled shifting, i.e., automatic shifting, of the transmission26so that the torque supplied to the wheels of the motor vehicle and/or the ground speed of the vehicle will be thereby limited. In one variant of this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively controls the transmission26to disable engagement of a drive gear of the transmission so that the motor vehicle will not be movable.

As yet another non-limiting example, the electronically controlled unit26may be an electronically controlled hydraulic (or pneumatic) actuator on-board the motor vehicle and the device(s)/actuator(s)28may be or include one or more hydraulically (or pneumatically) controlled attachments operatively coupled to the hydraulic actuator26, wherein the one or more hydraulically (or pneumatically) controlled attachments may be or include any conventional attachments including, but not limited to, any of the examples described hereinabove. In this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively disables operation of the electronically controlled hydraulic actuator26, thereby rendering inoperable any hydraulically-controlled attachment28operatively coupled thereto, or disables operation of at least one of the one or more hydraulically-controlled attachments28operatively coupled to the actuator26.

As yet a further non-limiting example, the electronically controlled unit26may be an electronically controlled power takeoff (PTO) unit on-board the motor vehicle and coupled, either directly or indirectly, to the engine of the motor vehicle, and the device(s)/actuator(s)28may be or include one or more PTO-driven attachments operatively coupled or couplable to the PTO unit26, wherein the one or more attachments may be or include any conventional PTO-driven or drivable attachments including, but not limited to, any of the examples described hereinabove. In this example, the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order illustratively disables operation of the electronically controlled PTO unit26, thereby rendering inoperable any PTO-driven or drivable attachment28operatively coupled or couplable thereto, or disables operation of at least one of the one or more attachments28operatively coupled or couplable to the PTO unit26.

Those skilled in the art will recognize the OUT1control signal produced by the processor22if/when the signals from the sensors S1, S2, S3are not each timely received in order may illustratively control other electronically controlled units26onboard the motor vehicle in a manner which disables or otherwise controls operation thereof and/or operation of one or more device(s), system(s) or actuator(s)28that may be operatively coupled thereto, and it will be understood that such other electronically controlled units26and/or one or more such other device(s), system(s) or actuator(s)28are contemplated by this disclosure.

Referring now toFIGS. 2A and 2B, an embodiment is shown of a retractor assembly50in which the sensor S2implemented in the retractor14in the form of a single shaft rotation detection switch. In the illustrated embodiment, the retractor14includes a frame52mounted to an anchor plate54via which the retractor assembly50may be mounted to the occupant seat12or floor F of the motor vehicle in a conventional manner. The retractor14further includes a rotatable shaft56rotatably mounted to the frame52. In the illustrated embodiment, the retractor14further includes a spool55carried by the shaft56such that the spool55rotates with the shaft56relative to the frame52. Illustratively, the spool55is configured to attach one end of the web16thereto such that the web16wraps around the spool55(and therefore also about the shaft56) as the shaft56and spool55together rotate in a web take-up direction to retract the web16into the retractor14, and such that the web16unwraps from the spool55(and therefore also from the shaft56) as the shaft56and spool55together rotate in a web pay-out direction to pay out the web16from the retractor14, as is conventional. In alternate embodiments, the spool55may be omitted, and the web16may be coupled directly to the shaft56such that the web16wraps and unwraps directly on and from the shaft56. In some embodiments, the retractor14further illustratively includes a conventional biasing member, e.g., spring, (not shown) which biases the rotatable shaft56(and/or spool55) in the web take-up direction, i.e., so that the web16normally retracts within the retractor14, and the biasing force of such a biasing member is illustratively selected so as to be overcome by manually pulling the web16away from the retractor14such that the rotatable shaft56rotates in the web payout direction to pay out the web16from the retractor14.

In the illustrated embodiment, S2is provided in the form of a single shaft rotation detection switch including a switch housing58mounted to the frame52of the retractor14or to another stationary component of the retractor14and an actuatable switch60carried by the switch housing58. The shaft56illustratively includes a cam lobe56A protruding radially away from the shaft56at least in the area of the shaft56that is adjacent to the switch housing58. One end of a resilient follower62is coupled to the switch housing58and an opposite end carries a protrusion64which contacts the shaft56. Between the two ends, the follower62illustratively contacts the switch60. The follower62is illustratively biased so that the protrusion64is normally forced away from the switch60and against the rotatable shaft56. The follower62is thus operatively coupled between and engages each of the retractor switch housing58and the rotatable shaft56such that the protrusion64of the follower62rides on the shaft56as it rotates. As long as the protrusion64of the follower62is not riding on or engaging the lobe56A, the switch60is not actuated by the follower62as illustrated inFIG. 2A. As illustrated inFIG. 2B, the shaft56has rotated from the position illustrated inFIG. 2Asuch that the protrusion64of the follower62contacts the cam lobe56A. The cam lobe56A forces the follower62sufficiently toward the switch60to actuate the switch60and cause the switch60to change states when the protrusion64of the follower62rides on or engages the cam lobe56A.

The switch60may illustratively be configured to be normally activated when the follower62is not engaging the cam lobe56A as illustrated inFIG. 2Aand to be unactivated when the follower is engaging the cam lobe56A as illustrated inFIG. 2B, or vice versa. In any case, the number of times that the switch60changes state as the web16is paid out of the retractor14will depend on how much of the web16, i.e., its length, is paid out from the shaft56and spool55. In one embodiment, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the retractor switch60and determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if the shaft56or spool55rotates a predefined number of times as detected by the processor22if/when the signal produced by the switch60changes between the two states a corresponding threshold number of times. Illustratively, the threshold number of times will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal produced by the retractor switch60, determining the number of times the signal produced by the switch60changes state, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of times the signal produced by the switch60changes state, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

It will be appreciated that whereas the rotatable shaft56illustrated inFIGS. 2A and 2Bincludes a single lobe56A, the shaft56may alternatively include any number of lobes extending radially outwardly therefrom. In the retractor assembly embodiment 70 illustrated inFIG. 3, for example, the shaft56′ defines two lobes56A,56B each extending radially away from one another in opposite directions, with the remaining components of the retractor assembly70being identical to those of the retractor assembly50illustrated inFIGS. 2A and 2B. In other alternative embodiments, the shaft56may define three or more lobes spaced evenly or unevenly about the shaft56. Generally, the resolution of shaft rotation or web length detection by the processor22will depend, at least in part, on the number of cam lobes defined on the retractor shaft56and no limit on the number of cam lobes that may be defined on the retractor shaft56is therefore intended by this disclosure.

Referring now toFIG. 4, another embodiment is shown of a retractor assembly80in which the sensor S2implemented in the retractor14in the form of a single shaft rotation detection sensor. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 4, S2illustratively includes a sensor body82mounted to the frame52of the retractor14or to another stationary component of the retractor14and proximity sensor84is carried by the sensor housing82and oriented toward the rotatable shaft56″ as shown. The shaft56″ is illustratively depicted as including three equally spaced apart cam lobes56A,56B,56C each protruding radially away from the shaft56at least in the area of the shaft56that is adjacent to the proximity sensor84, although it will be understood that more or fewer such cam lobes may be provided in alternate embodiments. In some embodiments, the proximity sensor may be a conventional capacitive sensor, although other conventional sensor technologies may be alternatively implemented. Examples of such other conventional sensor technologies may include, but are not limited to, inductive sensors (e.g., variable reluctance or other inductive sensors), magnetic sensors and the like. In any case, the proximity sensor84is configured to produce a lobe detection signal each time one of the lobes56A,56B,56C passes within a detection distance of the proximity sensor84. In this regard, the position of the sensor84relative to the shaft56″ is illustratively selected so as to be able to discriminate passage thereby of the lobes56A,56B,56C from the portions of the shaft56″ between the lobes56A,56B,56C. The instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the proximity sensor84to determine passage thereby any of the lobes56A,56B,56C, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of lobe detections are produced by the sensor84. Illustratively, the threshold number of lobe detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal produced by the sensor84to determine passage thereby any of the lobes56A,56B,56C, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of lobe detections produced by the sensor84, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

Referring now toFIG. 5, yet another embodiment is shown of a retractor assembly90in which the sensor S2implemented in the retractor14in the form of a single shaft, gear or wheel rotation detection switch. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 5, S2illustratively includes a switch body94mounted to the frame52of the retractor14or to another stationary component of the retractor14and switch96is carried by the switch housing94. A toothed gear or wheel92is mounted to the rotatable shaft56′″ such that the gear92rotates with the shaft56′″. The gear92illustratively defines a plurality of teeth at and about its outer periphery. The gear92may be configured with any number of such teeth, and therefore no limit on the number of teeth is intended or should be implied. In any case, one end of a resilient follower98is coupled to the switch housing94and an opposite end carries a protrusion102which is biased into contact with the outer periphery of the gear92as depicted inFIG. 5. Between the two ends, the follower98illustratively contacts the switch96. The follower98is thus operatively coupled between and engages each of the retractor switch96and the gear92with the protrusion102biased against and riding on the outer periphery of the gear92as it rotates with the shaft56′″.

Illustratively, the protrusion102defined at the free end of the follower98is sized to be received between adjacent teeth defined along the outer periphery of the gear92. In this regard, as long as the protrusion102of the follower98is received within a space between adjacent teeth defined along the outer periphery of the gear92, the switch96is not actuated by the follower96as illustrated by example inFIG. 5. However, as the gear92rotates, as indicated by the bi-directional arrow104, any tooth defined along the outer periphery of the gear92acting on the protrusion102will force the follower98sufficiently toward the switch96to actuate the switch96and cause it to change to states. The switch96may illustratively be configured to be normally activated when the follower96is received in a space between adjacent teeth defined along the outer periphery of the gear92and to be unactivated when the follower96is engaging one of the teeth defined along the periphery of the gear92, or vice versa.

In any case, the switch96is configured to produce a tooth detection signal each time one of the teeth forces the follower98against, and thereby actuating, the switch96. In this regard, the combination of the switch96, follower98and protrusion102is illustratively able to discriminate between the various teeth of the gear or wheel92and the spaces between the teeth. The instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the switch96to determine detection thereby of individual ones of the teeth defined about the periphery of the gear or wheel92as just described, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of tooth detections are produced by the switch96. Illustratively, the threshold number of tooth detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal produced by the switch96to determine detection thereby of individual ones of the teeth defined about the periphery of the gear or wheel92as just described, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of tooth detections produced by the switch96, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

Referring now toFIG. 6, still another embodiment is shown of a retractor assembly110in which the sensor S2implemented in the retractor14in the form of a single shaft, gear or wheel rotation detection switch. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 6, S2illustratively includes a sensor body112mounted to the frame52of the retractor14or to another stationary component of the retractor14and proximity sensor114carried by the sensor housing112. The shaft56′″ illustratively has a toothed wheel or gear92mounted thereto as described with respect toFIG. 5. In some embodiments, the proximity sensor114may be a conventional inductive sensor, although other conventional sensor technologies may be alternatively implemented. Examples of such other conventional sensor technologies may include, but are not limited to, capacitive sensors, magnetic sensors and the like. In any case, the proximity sensor114is configured to produce a tooth detection signal each time one of the teeth defined along the outer periphery of the gear92passes within a detection distance of the proximity sensor114. In this regard, the position of the sensor114relative to the shaft56′″ is illustratively selected so as to be able to discriminate passage thereby of the teeth from the spaces defined between the teeth. The instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensor114to determine detection thereby of individual ones of the teeth defined about the periphery of the gear or wheel92as just described, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of tooth detections are produced by the sensor114. Illustratively, the threshold number of tooth detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal produced by the sensor114to determine detection thereby of individual ones of the teeth defined about the periphery of the gear or wheel92as just described, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of tooth detections produced by the sensor114, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

Referring now toFIG. 7, a further embodiment is shown of a retractor assembly120in which the sensor S2implemented in the retractor14in the form of a single shaft, wheel or gear rotation sensor. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 7, S2illustratively includes a sensor122mounted to the frame52of the retractor14or to another stationary component of the retractor14. The shaft56′″ is illustratively depicted inFIG. 7as having a toothed wheel or gear92mounted thereto as described with respect toFIG. 5, although it will be understood that the teeth defined about the outer periphery of the wheel92may be omitted alternate embodiments the wheel92. In any case, the wheel92illustratively has four spaced apart magnets1241-1244affixed to or integrated into the planar face thereof such that the magnets1241-1244rotate with the wheel92about the shaft56′″, although it will be understood that more or fewer such magnets may be affixed to the wheel92in alternate embodiments.

The sensor122illustrated inFIG. 7is illustratively a conventional Hall-effect sensor configured to produce a magnet detection signal each time one of the magnets1241-1244disposed radially about the gear92passes within a detection distance of the sensor114. In this regard, the position of the sensor122relative to the face of the wheel92is illustratively selected so as to be able to discriminate passage thereby of the magnets1241-1244from the spaces between the magnets1241-1244. In alternate embodiments, other conventional magnet detection sensor technologies or other conventional sensor technologies may be implemented, examples of which may include, but are not limited to, capacitive sensors, inductive sensors and the like.

The instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensor122to determine detection thereby of individual ones of the magnets1241-1244spaced about the gear or wheel92as just described, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of magnet detections are produced by the sensor122. Illustratively, the threshold number of magnet detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal produced by the sensor122to determine detection thereby of individual ones of the magnets1241-1244spaced about the gear or wheel92as just described, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of magnet detections produced by the sensor122, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

Referring now toFIGS. 8A and 8B, yet another embodiment is shown of a retractor assembly130in which the sensor S2implemented in the retractor14in the form of two shaft, wheel or gear rotation sensors. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIGS. 8A and 8B, S2illustratively includes two sensors138,140each mounted to the frame52of the retractor14or to another stationary component of the retractor14. Illustratively, the sensors138,140are radially spaced apart from one another relative to and about the rotatable shaft56IVas shown.

The shaft56IVis illustratively depicted inFIGS. 8A and 8Bas having a wheel or gear132mounted such that the wheel or gear132rotates with the shaft56IVabout a rotational axis144of the shaft56IV. Two arc-shaped magnets134,136are defined at or adjacent to the outer periphery of the wheel132, and the magnets134,136are radially spaced apart from one another relative to the rotational axis144. In one embodiment, pockets are formed into the periphery of the wheel132, and the magnets134,136are inserted and secured therein. Alternatively, the magnets134,136may be affixed or integrated into the wheel132using any conventional technique(s). In the illustrated embodiment, the arc-shaped magnets134,136each define different arc lengths AR1, AR2respectively, wherein AR2>AR1as illustrated inFIG. 8A. Additionally, as also illustrated inFIG. 8A, a magnet axis M134passing through the rotational axis144of the shaft56IVand centrally through the magnet134(i.e., such that M134bi-sects the arc length AR1) and a magnet axis M136passing through the rotational axis144of the shaft56IVand centrally through the magnet136(i.e., such that M136bi-sects the arc length AR2) form an acute angle AG1therebetween (and also form an obtuse angle therebetween adjacent to the acute angle AG1).

The sensors138,140are, like the magnets134,136, radially spaced apart from one another relative to the rotational axis144of the shaft56IV. As illustrated inFIG. 8B, a sensor axis S138passing through the rotational axis144of the shaft56IVand centrally through the active surface of the sensor138facing the wheel132and a sensor axis S140passing through the rotational axis144of the shaft56IVand centrally through the active surface of the sensor140facing the wheel132form another acute angle AG2therebetween (and also form an obtuse angle therebetween adjacent to the acute angle AG2). Illustratively, the angles AG1and AG2are different from one another, although embodiments are contemplated in which AG1=AG2. In any case, at least one signal path146A is connected between the sensor138and the processor22, and at least one signal path146B is connected between the sensor140and the processor22.

In the illustrated embodiment, the sensors138,140are illustratively conventional Hall-effect sensors each configured to produce a magnet detection signal each time one of the magnets134,136passes within a detection distance thereof. In this regard, each sensor138,140is positioned relative to the face of the wheel132so as to be able to discriminate passage thereby of the magnets134,136from the spaces between the magnets134,136. In alternate embodiments, the magnets134,136may have other shapes, i.e., shapes other than arcs, and/or may be positioned adjacent to the outer periphery of the wheel132, i.e., at least partially inboard. In some such embodiments, the sensors138,140may extend over (or under) the wheel132as viewed in the two-dimensional depiction illustrated inFIGS. 8A and 8B. In alternate embodiments, other conventional magnet detection sensor technologies or other conventional sensor technologies may be implemented, examples of which may include, but are not limited to, capacitive sensors, inductive sensors and the like.

In one embodiment, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensors138,140to determine detection by each of passage thereby of individual ones of the magnets134,136spaced about the gear or wheel132as just described, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of magnet detections are produced by one or both of the sensors138,140. Illustratively, the threshold number of magnet detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by either of both of the sensors138,140to determine detection thereby of individual ones of the magnets134,136spaced about the gear or wheel132as just described, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of magnet detections produced by either or both of the sensors138,140, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

In some embodiments, the signals produced by the two sensors138,140may be processed by the processor22to determine both rotational information, i.e., the number of full and/or partial rotations of the shaft56IVand directional information, i.e., whether the shaft56IVis rotating in a clockwise or counterclockwise direction. In such embodiments, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to process the signals produced by the sensors138,140to determine the number of rotations and/or partial rotations of the shaft56IVas well as the direction of rotation of the shaft56IV, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if, based on such rotation amount and rotational direction information, the processor22determines that the shaft56IVhas rotated at least a threshold amount, i.e., at least a predefined number of rotations and/or partial rotations, in the web payout direction. Illustratively, the threshold rotation amount (in the web payout direction) will be chosen to correlate to a desired threshold length of the web16paid out by the retractor14in the web payout direction. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by the sensors138,140to estimate or otherwise determine a length of web paid out of the retractor14based on such rotation amount and rotational direction information, and to determine that “the threshold length of web” is paid out of the retractor14if the estimated or otherwise determined length of web meets or exceeds a threshold web length value.

Referring now toFIGS. 9A and 9B, still another embodiment is shown of a retractor assembly150in which the sensor S2implemented in the retractor14in the form of two shaft, wheel or gear rotation sensors. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIGS. 9A and 9B, S2illustratively includes two sensors164,166each mounted to the frame52of the retractor14or to another stationary component of the retractor14. Illustratively, the sensors164,166are radially spaced apart from one another relative to and about the rotatable shaft56Vas shown.

The shaft56Vis illustratively depicted inFIGS. 9A and 9Bas having a two arc-shaped ends or lobes152,154generally opposite one another with each set of opposing arc ends joined together by generally opposite linear walls156,158. The shaft56Vis illustratively rotatable about a rotational axis160in either of the directions162depicted inFIG. 9A. In the illustrated embodiment, the arc-shaped magnets152,154each define different arc lengths between the walls156,158, wherein the arc length of the arc-shaped end154is greater than the arc length of the arc-shaped end152. As illustrated by example inFIG. 9B, an arc axis A152passing through the rotational axis160of the shaft56Vand centrally through the arc-shaped end152(i.e., such that A152bi-sects the arc length of the arc-shaped end152) and an arc axis A154passing through the rotational axis160of the shaft56Vand centrally through the arc-shaped end154(i.e., such that A154bi-sects the arc-shaped end154) form an acute angle AG4therebetween.

The sensors164,166are, like the arc-shaped ends152,154of the rotatable shaft56V, radially spaced apart from one another relative to the rotational axis160of the shaft56V. As illustrated inFIG. 9A, a sensor axis S164passing through the rotational axis160of the shaft56Vand centrally through the active surface of the sensor164facing the shaft56Vand a sensor axis S166passing through the rotational axis160of the shaft56Vand centrally through the active surface of the sensor166facing the shaft56Vform another acute angle AG3therebetween (and also form an obtuse angle therebetween adjacent to the acute angle AG3). Illustratively, the angles AG3and AG4are different from one another, although embodiments are contemplated in which AG3=AG4. In any case, at least one signal path168A is connected between the sensor164and the processor22, and at least one signal path168B is connected between the sensor166and the processor22.

In the illustrated embodiment, the sensors164,166are illustratively conventional proximity sensors each configured to produce a lobe detection signal each time one of the arc-shaped ends or lobes152,154of the shaft56Vpasses within a detection distance thereof. In this regard, each sensor164,166is positioned relative to the shaft56Vso as to be able to discriminate passage thereby of each of the arc-shaped ends or lobes152,154from the side walls156,158thereof. In alternate embodiments, the ends152,154of the shaft56Vmay have other shapes, i.e., shapes other than arcs. In alternate embodiments, other conventional sensor technologies or may be implemented, examples of which may include, but are not limited to, capacitive sensors, inductive sensors, magnetic sensors, and the like.

In one embodiment, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensors164,166to determine detection by each of passage thereby of individual ones of the arc-shaped ends or lobes152,154of the rotatable shaft56V, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of lobe detections are produced by one or both of the sensors164,166. Illustratively, the threshold number of lobe detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by either of both of the sensors164,166to determine detection thereby of individual ones of the lobes152,154, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of lobe detections produced by either or both of the sensors164,166, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

In some embodiments, the signals produced by the two sensors164,166may be processed by the processor22to determine both rotational information, i.e., the number of full and/or partial rotations of the shaft56Vand directional information, i.e., whether the shaft56Vis rotating in a clockwise or counterclockwise direction. In such embodiments, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to process the signals produced by the sensors164,166to determine the number of rotations and/or partial rotations of the shaft56Vas well as the direction of rotation of the shaft56V, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if, based on such rotation amount and rotational direction information, the processor22determines that the shaft56Vhas rotated at least a threshold amount, i.e., at least a predefined number of rotations and/or partial rotations, in the web payout direction. Illustratively, the threshold rotation amount (in the web payout direction) will be chosen to correlate to a desired threshold length of the web16paid out by the retractor14in the web payout direction. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by the sensors164,166to estimate or otherwise determine a length of web paid out of the retractor14based on such rotation amount and rotational direction information, and to determine that “the threshold length of web” is paid out of the retractor14if the estimated or otherwise determined length of web meets or exceeds a threshold web length value.

Referring now toFIG. 10, a further embodiment is shown of a retractor assembly170in which the sensor S2implemented in the retractor14in the form of two shaft, wheel or gear rotation sensors. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 10, the rotatable shaft56Videntical to the shaft56VofFIGS. 9A and 9Band described above, and like numbers are therefore used to identify like components.

In the illustrated embodiment, S2illustratively includes two sensors176,178each mounted to the frame52of the retractor14or to another stationary component of the retractor14. The sensors176,178are radially spaced apart from one another relative to the rotational axis160of the shaft56V. Two magnets172,174are also mounted to the frame52of the retractor14or to another stationary component of the retractor14. One of the magnets172is positioned adjacent to the sensor176such that the sensor176is positioned between the magnet172and the shaft56V, and the other magnet174is positioned adjacent to the sensor178such that the sensor178is positioned between the magnet174and the shaft56V. The magnets172,174are thus, like the sensors176,178, radially spaced apart from each another relative to the rotational axis160of the shaft56V.

As illustrated inFIG. 10, a sensor axis S176passes through the rotational axis160of the shaft56V, centrally through the active surface of the sensor176facing the shaft56Vand centrally through the magnet172. Another sensor axis S178passes through the rotational axis160of the shaft56V, centrally through the active surface of the sensor178facing the shaft56Vand centrally through the magnet174. The sensor axes S176and S178illustratively form an acute angle AG5therebetween (and also form an obtuse angle therebetween adjacent to the acute angle AG5), although in other embodiments AG5may be a right angle. Illustratively, the angles AG4and AG5are different from one another, although embodiments are contemplated in which AG4=AG5. In any case, at least one signal path175A is connected between the sensor176and the processor22, and at least one signal path1758is connected between the sensor178and the processor22.

In the illustrated embodiment, the sensors176,178are illustratively conventional Hall-effect sensors each configured to produce a magnet detection signal each time one of the arc-shaped ends or lobes152,154of the shaft56Vpasses within a detection distance thereof. In this regard, the differently-shaped lobes152,154are metal or metal-coated so as to affect the magnetic fields produced by the magnets172,174differently. Accordingly, each sensor176,178is able to discriminate passage thereby of each of the arc-shaped ends or lobes152,154from each other and from the side walls156,158thereof. In alternate embodiments, the ends152,154of the shaft56Vmay have other shapes, i.e., shapes other than arcs. In alternate embodiments, other conventional sensor technologies or may be implemented, examples of which may include, but are not limited to, capacitive sensors, inductive sensors, magnetic sensors, and the like.

In one embodiment, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensors176,178to determine detection by each of passage thereby of individual ones of the arc-shaped ends or lobes152,154of the rotatable shaft56V, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of lobe detections are produced by one or both of the sensors176,178. Illustratively, the threshold number of lobe detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by either of both of the sensors176,178to determine detection thereby of individual ones of the lobes152,154, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of lobe detections produced by either or both of the sensors176,178, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

In some embodiments, the signals produced by the two sensors176,178may be processed by the processor22to determine both rotational information, i.e., the number of full and/or partial rotations of the shaft56Vand directional information, i.e., whether the shaft56Vis rotating in a clockwise or counterclockwise direction. In such embodiments, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to process the signals produced by the sensors176,178to determine the number of rotations and/or partial rotations of the shaft56Vas well as the direction of rotation of the shaft56V, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if, based on such rotation amount and rotational direction information, the processor22determines that the shaft56Vhas rotated at least a threshold amount, i.e., at least a predefined number of rotations and/or partial rotations, in the web payout direction. Illustratively, the threshold rotation amount (in the web payout direction) will be chosen to correlate to a desired threshold length of the web16paid out by the retractor14in the web payout direction. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by the sensors176,178to estimate or otherwise determine a length of web paid out of the retractor14based on such rotation amount and rotational direction information, and to determine that “the threshold length of web” is paid out of the retractor14if the estimated or otherwise determined length of web meets or exceeds a threshold web length value.

Referring now to now toFIG. 11, still another embodiment is shown of a retractor assembly180in which the sensor S2implemented in the retractor14in the form of two shaft, wheel or gear rotation sensors. In the illustrated embodiment, many of the components and features of the retractor14are as described with respect toFIGS. 2A and 2B, and like numbers are therefore used to identify like components. In the embodiment illustrated inFIG. 11, the sensors176,178and the magnets172,174are identical to those illustrated inFIG. 10and described above, and like numbers are therefore used to identify like components.

The shaft56VIis illustratively depicted inFIG. 11as having an arc-shaped end or lobe184and a flat or linear end186each generally opposite the other. In the illustrated embodiment, the end or lobe184has a semi-circular cross section, although in other embodiments the cross section of the end or lobe184may include more or less of the circle. The shaft56VIis illustratively rotatable about a rotational axis182in either direction. In the illustrated embodiment, each sensor176,178is able to discriminate passage thereby of each of the arc-shaped end or lobe184and the flat or linear portion186from each other.

In one embodiment, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to monitor the sensors176,178to determine detection by each of passage thereby of individual ones of the arc-shaped end or lobe184and the flat or linear portion186of the rotatable shaft56VI, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if a threshold number of lobe detections are produced by one or both of the sensors176,178. Illustratively, the threshold number of lobe detections will be chosen to correlate to a desired threshold length of the web16. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by either of both of the sensors176,178to determine detection thereby of individual ones of the lobes152,154, determining or estimating the amount, i.e., length, of the web16that is paid out of the retractor14as a function of the number of lobe detections produced by either or both of the sensors176,178, and then comparing the determined or estimated length of the paid out portion of the web16to a threshold web length value.

In some embodiments, the signals produced by the two sensors176,178may be processed by the processor22to determine both rotational information, i.e., the number of full and/or partial rotations of the shaft56VIand directional information, i.e., whether the shaft56VIis rotating in a clockwise or counterclockwise direction. In such embodiments, the instructions stored in the memory24illustratively include instructions which, when executed by the processor22, cause the processor22to process the signals produced by the sensors176,178to determine the number of rotations and/or partial rotations of the shaft56VIas well as the direction of rotation of the shaft56VI, and to determine that the “threshold length of web,” as described above in the sequence detection of S1, S2, S3, is paid out of the web retractor14if, based on such rotation amount and rotational direction information, the processor22determines that the shaft56VIhas rotated at least a threshold amount, i.e., at least a predefined number of rotations and/or partial rotations, in the web payout direction. Illustratively, the threshold rotation amount (in the web payout direction) will be chosen to correlate to a desired threshold length of the web16paid out by the retractor14in the web payout direction. In alternative embodiments, the instructions stored in the memory24may include instructions which, when executed by the processor22, cause the processor22to determine that the “threshold length of web” is paid out of the web retractor14by processing the signal(s) produced by the sensors176,178to estimate or otherwise determine a length of web paid out of the retractor14based on such rotation amount and rotational direction information, and to determine that “the threshold length of web” is paid out of the retractor14if the estimated or otherwise determined length of web meets or exceeds a threshold web length value.

Referring now toFIG. 12, a simplified flowchart is shown of an embodiment of a process200for detecting and acting upon an operating state of the restraint system depicted inFIG. 1. Illustratively, the process200is stored in the memory24in the form of instructions which, when executed by the processor22, cause the processor to execute the illustrated acts. The process200begins at step202where the processor200is operable to monitor the sensors S1, S2, S3, i.e., to monitor the signals produced by the sensors S1, S2, S3. In the embodiment of the flowchart illustrated inFIG. 12, the sensor S1is assumed to be a pressure sensor or switch, the sensor S3is assumed to be a latch sensor or switch, and the sensor(s) S2may be implemented in any of the forms described above. It will be understood that in alternate embodiments of the process200, the sensor S1and/or the sensor S3may be implemented in other forms, some examples of which are described hereinabove.

In any case, the process200advances from step202to step204where the processor22is operable to determine whether the sensor S1produces a pressure signal, P, that is greater than or equal to a threshold pressure PTH. In one embodiment, PTHis selected to correspond or correlate to a pressure above which will be applied to the seat bottom12A when an average-sized adult is seated in the occupant seat12. In other embodiments, PTHmay be selected to have a greater or lesser value. If, at step204, the processor22determines that P is less than PTH, the process200loops back to the beginning of step204. If, on the other hand, the processor22determines at step204that P≥PTH, the process200advances to step206where the processor22is illustratively operable to reset a web length timer, WLT, e.g., to set the timer WLT equal to zero or other constant value.

Thereafter at step208, the processor22is operable to determine from the sensor signal(s) produced by the sensor(s) S2whether the web length, WL, paid out of the retractor14is greater than or equal to a web length threshold value WL TH. Illustratively, the web length threshold value WLTHis selected to take into account the combination of the linear distance between the tongue18and the buckle20when the web16is fully retracted within the web retractor14and an additional length of the web16required to wrap at least partially about an average-sized adult seated in the occupant seat12.

Examples of execution by the processor22of step208of the process200have been provided hereinabove with respect to each of the embodiments of the web retractor14illustrated inFIGS. 2A-11. Additional example processes that may be executed by the processor22at step208are illustrated inFIGS. 13 and 14which will be described in detail below. In any case, if the processor22determines at step208that WL is less than WLTH, the process200advances to step210where the processor22is operable to determine whether the web length timer WLT, which was reset at step206, has advanced to a time value greater than or equal to a threshold time value T1. Illustratively, T1is in the range of 1-20 seconds, although in other embodiments T1may alternatively be less than 1 second or greater than 20 seconds. If the processor22determines at step210that WLT is less than T1, the process200loops back to the beginning of step208. If, however, the processor22determines at step210that WLT T1, the process200advances to step212where the processor22is operable to produce the control signal(s) OUT1and/or OUT2to disable or impede operation of the motor vehicle and/or to activate a notification device30and/or to control the wireless communication circuitry32, in embodiments which include such circuitry32, to transmit a wireless control signal to activate one or more remote notification devices34or to control one or more remote notification devices34to display a message or report, all as described hereinabove. Thus, after the processor22determines at step204that an occupant has been seated in the occupant seat12, the occupant must draw at least the threshold length WLTHof web16from the retractor14within the time period T1or step212will be executed by the processor22.

If, at step214, the processor22determines that WL WLTHwithin the time period T1, the process200advances to step214where the processor22is illustratively operable to reset a buckle engagement timer, BET, e.g., to set the timer BET equal to zero or other constant value. Thereafter at step216, the processor22is operable to determine from the sensor signal produced by the sensor S3whether the tongue18and the buckle20have engaged one another as described above. If not, the process200advances to step218where the processor22is operable to determine whether the buckle engagement timer BET, which was reset at step214, has advanced to a time value greater than or equal to a threshold time value T2. In one embodiment, T2=T1, although in alternate embodiments T2may be selected such that T2≠T1. If the processor22determines at step218that BET is less than T2, the process200loops back to the beginning of step216. If, however, the processor22determines at step218that BET T2, the process200advances to step212where the processor22is operable as described above. Thus, after the processor22determines at step204that an occupant has been seated in the occupant seat12, and thereafter determines that at least the threshold length of web WLTHwas drawn from the retractor within the time period T1after detection of the occupant being seated in the occupant seat12, the occupant engage the tongue18with the buckle20within the time period T2or step212will be executed by the processor22.

If, at step216, the processor22determines that the tongue18and buckle20have engaged one another within the time period T2, the processor22does not execute step212, and the processor22therefore does not produce any control signals to disable or impede operation of the motor vehicle, to activate any on-board notification devices30or to activate or otherwise control any remote notification devices34. Thus, if the processor22determines that at least the threshold length of web WLTHis drawn from the retractor14within the time period T1after detection of the occupant being seated in the occupant seat12, and then determines that the tongue18and buckle20have engaged one another within the time period T2after determining that the threshold length of web WLTHwas drawn from the retractor14, the motor vehicle operates in a normal manner and no notification devices are activated or otherwise controlled by the processor22.

In some of the example web retractor assembly embodiments just described with respect toFIGS. 2A-11, the shaft rotation sensor(s) implemented therein are capable of detecting small amounts of movement of the web16that typically and expectedly occurs as a result of movement of the occupant within the vehicle seat12, e.g., due to movement of the motor vehicle itself and/or due to the operation of one or more hydraulically/pneumatically or PTO-driven attachments. Detection of such small amounts of movement of the web16relative to the retractor14may illustratively be used to distinguish between a properly deployed web16, i.e., in which the web16extends about and engages the occupant, and an improperly deployed web, e.g., in which the tongue18is engaged with the buckle20with the web16located between the occupant and the seat12or with the web16otherwise not engaging the occupant. In such embodiments, the processor22may illustratively be programmed, e.g., via appropriate instructions stored in the memory24, to continue to monitor S2following the YES branch of step216. During such subsequent monitoring, the processor22may continue to monitor S2and to produce the control signal(s) OUT1and/or OUT2if the signal produced by S2does not indicate a threshold amount of movement of the web16relative to the web retractor14, e.g., over some time period.

In some such embodiments, for example, the process200may include an additional step220following the YES branch of step216. In such embodiments, the processor22is illustratively operable at step220to execute a web length monitoring process. If the sequence of events determined at steps204-218have occurred so as to arrive at the YES branch of step218, the restraint harness15should be extended over at least a portion of the occupant while seated in the occupant seat12. If so, then during subsequent operation of the motor vehicle, small amounts of the web16should be expected to move into and out of the web retractor14as the motor vehicle encounters bumps and/or turns, and/or as the operation of attachments28to hydraulic, pneumatic and/or PTO-driven control units26jostle or otherwise move the motor vehicle, so as to cause the occupant of the seat12to move into and away from the web16. In embodiments that include step220of the process200, the processor22is illustratively operable to monitor the sensor(s) S2to determine whether an expected amount of such movement of the web16occurs. One example of a web length monitoring process that may be executed by the processor22at step220is illustrated inFIG. 17and will be described in detail below.

Referring now toFIG. 13, an embodiment is shown of a process250for executing step208of the process200illustrated inFIG. 12. The process250may be executed at step208of the process200when implementing any of the embodiments of the web retractor14illustrated inFIGS. 2A-11. In embodiments that include it, the process250is illustratively stored in the memory24in the form of instructions which, when executed by the processor22, cause the processor22to carry out the illustrated acts. The process250begins at step252where the processor22is operable to reset a shaft rotation value, SR, e.g., to set SR equal to zero or other constant value. Thereafter at step254, the processor22is operable to monitor the shaft rotation sensor(s) S2, and at step256the processor22is operable to determine, based on the sensor signal(s), whether a lobe or tooth is detected as described above. If not, the process250loops back to the beginning of step254. If, at step256, the processor22determines that a lobe or tooth is detected, the process250advances to step258where the processor22is operable to add a rotation increment value, ROTINC, to the current shaft rotation value, SR. The rotation increment value, ROTINC, illustratively corresponds to an incremental amount of rotation of the retractor shaft between the lobe(s) or teeth defined on the shaft, gear or wheel of the particular retractor. For example, the retractor assembly50illustrated inFIGS. 2A and 2Bdefines a single lobe56A on the rotatable shaft56, and in this embodiment the rotation increment value, ROTINC, is equal to one complete rotation of the shaft56. As another example, the retractor assembly90illustrated inFIG. 5defines 44 teeth along the periphery of the gear92, and in this embodiment the rotation increment value, ROTINC, is equal to 1/44 rotation of the shaft56′″.

Following step258, the process250illustratively advances to step260where the processor22is operable to compute a web length, WL, as a function of the current shaft rotation value, SR. Illustratively, this function may compute WL as a function of SR and a combination of the diameter of the rotatable shaft (or spool) and an additional diameter of an average or estimated number of windings of the web16about the shaft (or spool). In other embodiments, the function computed at step260may include other factors such as the thickness of the web16, the reduction in the diameter of the combination of the shaft (or spool) and web16wrapped around the shaft (or spool) as the web16is paid out of the retractor, and the like. In any case, the process250illustratively loops from step260back to step254.

In some embodiments of the process250, step260may be omitted, and in such embodiments the processor22may be operable at step208of the process200to compare SR to a shaft rotation threshold value SRTHin place of comparing WL to WLTH. In other such embodiments, the processor22may be operable at step208to compute WL as a function of SR and to then execute the comparison of WL with WLTH.

Referring now toFIG. 14, an embodiment is shown of another process300for executing step208of the process200illustrated inFIG. 12. The process300may illustratively be executed at step208of the process200when implementing any of the embodiments of the web retractor14that include two or more shaft rotation sensors from which shaft rotation amount and shaft rotation direction can be determined; e.g., when implementing any of the embodiments of the web retractor14illustrated inFIGS. 8A-11. In embodiments that include it, the process300is illustratively stored in the memory24in the form of instructions which, when executed by the processor22, cause the processor22to carry out the illustrated acts. The process300begins at step302where the processor22is operable to reset a shaft rotation value, SR, e.g., to set SR equal to zero or other constant value. Thereafter at step304, the processor22is operable to monitor the shaft rotation sensor(s) S2, and at step306the processor22is operable to determine, based on the sensor signal(s), whether a lobe or tooth is detected as described above. If not, the process300loops back to the beginning of step304. If, at step306, the processor22determines that a lobe or tooth is detected, the process300advances to step308where the processor22is operable to determine a rotational direction (DIR) of the rotatable shaft, e.g., a clockwise (CW) or counterclockwise (CCW) rotational direction of the shaft, or a retraction direction, i.e., a rotational direction of the shaft in a web take up direction in which the web16is being retracted into the retractor14, or extraction direction of the shaft, i.e., a rotational direction of the shaft in a web payout direction in which the web16is being extracted from the retractor14.

Referring now toFIGS. 15A and 15B, timing diagrams are shown depicting logic states of the outputs of the two sensors in the web retractor assemblies illustrated inFIGS. 8A, 8B, inFIGS. 9A and 9Band inFIG. 10. The sensors138,164and176illustratively correspond to CH#1 inFIGS. 15A and 15B, and the sensors140,166and178illustratively correspond to CH#2 inFIGS. 15A and 15B. In any case, the processor22is illustratively operable at step308of the process300to monitor the sensor outputs and determine when CH#1 and CH#2 are both at low logic states. When CH#1 then transitions to a high logic state, the logic state of CH#2 determines the direction of rotation. For example, as illustrated inFIG. 15A, when CH#1 and CH#2 are both at low logic states and CH#1 then transitions to a high logic state, CH#2 is at a low logic state, thereby indicating clockwise rotation of the shaft56IV,56V. Similarly, as illustrated inFIG. 15B, when CH#1 and CH#2 are both at low logic states and CH#1 then transitions to a high logic state, CH#2 is at a high logic state, thereby indicating counterclockwise rotation of the shaft56IV,56V.

Referring now toFIGS. 16A and 16B, timing diagrams are shown depicting logic states of the outputs of the two sensors in the web retractor assemblies illustrated inFIG. 11. The sensor176illustratively corresponds to CH#1 inFIGS. 16A and 16B, and the sensor178illustratively corresponds to CH#2 inFIGS. 16A and 16B. In any case, the processor22is illustratively operable at step308of the process300to monitor the sensor outputs and determine when CH#1 and CH#2 are both at low logic states. If CH#2 then transitions to a high logic state while CH#1 remains at a low logic state, as illustrated inFIG. 16A, this indicates rotation of the shaft56VIin a direction in which the web is being extracted from the retractor14, i.e., the shaft56VIis rotating in the web payout direction. Similarly, as illustrated inFIG. 16B, if CH#1 and CH#2 are both at low logic states and CH#1 then transitions to a high logic state while CH#2 remains at a low logic state, this indicates rotation of the shaft56VIin a direction in which the web is being retracted into the retractor14, i.e., the shaft56VIis rotating in the web take-up direction.

Referring again toFIG. 14, if the processor22determines at step308that the retractor shaft is rotating in the clockwise direction, CW, (or in the web extraction direction), the process300advances to step310where the processor22is operable to add a rotation increment value, ROTINC, to the current shaft rotation value, SR. If, on the other hand, the processor22determines at step308that the retractor shaft is rotating in the counterclockwise direction, CCW, (or in the web retraction direction), the process300advances to step312where the processor22is operable to subtract the rotation increment value, ROTINC, from the current shaft rotation value, SR. Illustratively, SR and ROTINC are as described with respect toFIG. 13. In any case, it should be apparent that with the additional web direction information, the value of SR is more accurately indicative of the amount of web paid out from the retractor than the value of SR determined according to the process250illustrated inFIG. 13.

Following either of steps310and312, the process300illustratively advances to step314where the processor22is operable to compute a web length, WL, as a function of the current shaft rotation value, SR. This function is illustratively as described above with respect toFIG. 13, and the process300illustratively loops from step214back to step304. In some embodiments of the process300, step314may be omitted, and in such embodiments the processor22may be operable at step208of the process200to compare SR to a shaft rotation threshold value SRTHin place of comparing WL to WLTH. In other such embodiments, the processor22may be operable at step208to compute WL as a function of SR and to then execute the comparison of WL with WLTH.

Referring now toFIG. 17, an embodiment is shown of a web length monitoring process400in embodiments in which the process200illustrated inFIG. 12includes step220. In embodiments that include it, the process400is illustratively stored in the memory24in the form of instructions which, when executed by the processor22, cause the processor22to carry out the illustrated acts. The process400begins at step402where the processor22is operable to reset a timer value, T, and a count value, C, e.g., to set each of T and C equal to zero or other constant value. Thereafter at step404, the processor22is operable to monitor the shaft rotation sensor(s) S2, and at step406the processor22is operable to determine, based on the sensor signal(s), whether a lobe or tooth is detected as described above. If not, the process400loops back to the beginning of step404. If, at step406, the processor22determines that a lobe or tooth is detected, the process400advances to step408where the processor22is operable to increment the count value, C, by 1 or some other constant value. Thereafter at step410, the processor22is operable to determine whether the timer value, T, has increased to or beyond a threshold time TTH. If not, the process400loops back to step404, and otherwise the process400advances to step412where the processor22determines whether the count value, C, meets or exceeds a threshold count value, CTH. If so, the process400loops back to step402, and otherwise the process400advances to step414where the processor22executes a step identical to step212described in detail above with respect to the process200ofFIG. 12.

Under the direction of the process400, the processor22is thus operable to determine whether the web16moves into and/or out of the retractor14a threshold number of times within a specified time period, as should be expected if the web16is properly positioned about the occupant of the seat12. The values of CTHand TTHwill typically depend upon the type and use of the motor vehicle in which the restraint system10is implemented. In some embodiments, CTHand/or TTHmay be static values stored in the memory24. In other embodiments, CTHand/or TTHmay be dynamic values that change depending upon one or more operating conditions of the motor vehicle. For example, in some embodiments the value(s) of CTHand/or TTHmay depend upon the moving speed of the motor vehicle, e.g., CTHmay decrease and/or TTHmay increase with decreasing vehicle speed. As another example, the value(s) of CTHand/or TTHmay change with engine speed, e.g., CTHmay increase and/or TTHmay decrease with increasing engine speed. As yet another example, the value(s) of CTHand/or TTHmay change depending upon the operational status of an on-board hydraulic, pneumatic or PTO unit, e.g., CTHmay increase and/or TTHmay decrease when an on-board hydraulic, pneumatic or PTO unit is activated. Those skilled in the art will recognize that dynamic modification of CTHand/or TTHmay be based, at least in part, on other operating conditions of the motor vehicle, and it will be understood that any such dynamic modifications of CTHand/or TTHare contemplated by this disclosure. It will be further understood that the count and time based process400illustrated inFIG. 17is provided only by way of example. Those skilled in the art will recognize other techniques for monitoring incremental movement of the web16, and some such other techniques may or may not rely on or implement a count value, C, and/or a timer T as implemented in the example illustrated inFIG. 17. It will be understood, however, that any such other techniques for monitoring incremental movement of the web16are contemplated by, and are intended to fall within the scope of, this disclosure.

While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications consistent with the disclosure and recited claims are desired to be protected.