Vehicle safety device

Claim 3

A system as in claim 1, wherein said transmitting means includes antenna means on the conveyance and coupled to said detecting means for transmitting the undulatory radiation along the first pattern, and wherein said receiving means includes receiving antenna means mounted on said conveyance and coupled to said detecting means for receiving the undulatory radiation along the second pattern, said antenna means each directing their pattern ahead of the vehicle so the patterns intersect at an acute angle.

Claim 4

A system as in claim 1, wherein said detecting means includes Doppler sensing means for producing a Doppler signal which is a measure of the speed of an object in the sensitivity zone, said horizontal pattErns being sufficiently wide so that the sensitivity zone extends across the width of the conveyance.

Claim 5

A system as in claim 3, wherein said detecting means includes frequency to voltage converter means coupled to said Doppler means for producing a voltage proportional to the frequency of the Doppler signal, said detecting means further including threshold means connected to said converter means for inhibiting the output signal unless it exceeds a given value.

Claim 6

A system as in claim 4, wherein said detecting means further includes second threshold means connected to said Doppler sensing means for producing a control signal only when the level of the Doppler signal exceeds a predetermined value, and AND means for producing signals only in response to signals from both of said threshold means.

Claim 7

A system as in claim 1 wherein the pattern defined by said receiving means includes a plurality of beams each intersecting the transmitted pattern, and wherein said detecting means detects the difference between the frequency of said pattern and the frequency of reflected signals received along each of the beams, and output means in said detecting means for producing an output only when the differences between each of the reflected signals received by said receiving means and the first frequency exceeds a predetermined difference, said horizontal patterns being sufficiently wide so that the sensitivity zone extends across the width of the conveyance.

Claim 8

A system as in claim 6, wherein said detecting means includes Doppler sensing means for each of the beams and the pattern.

Claim 9

A system as in claim 7, wherein said detecting means includes a plurality of frequency to voltage converter means each coupled to one of said detecting means for producing a voltage proportional to the frequency of the Doppler signal, said detecting means further including a plurality of threshold means each connected to said converter means for inhibiting output of signals from said converter means unless the signal exceeds a given value.

Claim 10

A system as in claim 8, wherein said detecting means includes a plurality of second threshold means each connected to said Doppler sensing means for producing a signal from each only when the level of the corresponding Doppler signal exceeds a predetermined value, and AND means connected to each of said first and second threshold means for producing signals only when both of said first and second threshold means produce signals.

Claim 11

A system as in claim 6, wherein said detecting means includes divider means for comparing the frequency differences established in said detecting means for each of the beams and the pattern, and comparator means for inhibiting the output signal unless the comparison lies within a predetermined range.

Claim 12

A system as in claim 9, wherein said detecting means includes dividing means connected to each of said frequency to voltage converter means for establishing a relationship between the frequency differences detected by said Doppler means, and comparator means for producing a signal and applying it to said AND means only when the relationship lies with a given range.

Claim 13

A system as in claim 6, wherein said transmitting means includes a plurality of transmitting antennas and said receiving means includes a plurality of receiving antennas vertically displaced from respective ones of said transmitting antennas, each transmitting antenna transmitting undulatory radiation along the beam and each receiving antenna defining a beam vertically intersecting at least one of the beams transmitted by said transmitting antenna.

Claim 14

A system as in claim 10, wherein said transmitting means includes a plurality of transmitting antennas and said receiving means includes a plurality of receiving antennas vertically displaced from respective ones of said transmitting antennas, each transmitting antenna transmitting undulatory radiation along a beam, each receiving antenna defining a beam vertically interSecting at least a respective one of the beams transmitted by said transmitting antennas.

Claim 15

A system as in claim 11, wherein said transmitting means includes a pair of transmitting antennas and said receiving means includes a pair of receiving antennas vertically displaced from respective ones of said transmitting antennas, each transmitting antenna transmitting undulatory radiation along a beam, and each receiving antenna defining a beam vertically intersecting a respective one of the beams transmitted by said transmitting antennas, said pair of transmitting antennas being located on opposite sides of the front of the conveyance, said pair of receiving antennas being located on opposite sides of the front of the conveyance.

Claim 16

A system as in claim 6, wherein said transmitting means includes a transmitting antenna mounted on the vehicle and said receiving means includes four receiving antennas mounted around said transmitting antenna.

Claim 17

A potential collision detecting device, comprising a generator which generates an undulatory signal having a first frequency, a transmitting antenna which radiates said undulatory signal, a receiving antenna having a receiving axis intersecting the radiation axis of the transmitting antenna within a predetermined region and adapted to receive the undulatory signal from a reflected object and having a second frequency, said receiving and transmitting antennas radiating and receiving the undulatory signals along respective beams which are sufficiently narrow and intersect each other at a sufficient angle so that the beams converge and then overlap and then completely diverge from each other, sensing means for obtaining a Doppler signal having a frequency difference between the two frequencies, a frequency voltage converter for obtaining an electrical quantity proportional to the frequency of the Doppler signal, a first circuit which issues signals only when the electrical quantity exceeds a predetermined value, a second circuit which issues a signal only when the level of the Doppler signal exceeds a predetermined value, and an AND circuit for issuing a signal only when both the first and second circuits issue signals, said transmitting antenna and said receiving antenna being vertically displaced relative to each other and producing the beams so that they spread horizontally and so that the beams converge vertically and then overlap vertically and then completely diverge from each other vertically.

Claim 18

A potential collision detecting device, comprising a generator which generates an undulatory signal having a first frequency, a transmitting antenna which radiates said undulatory signal, a receiving antenna having a receiving axis intersecting the radiation axis of the transmitting antenna within a predetermined region and adapted to receive the undulatory signal from a reflected object and having a second frequency, said receiving and transmitting antennas radiating and receiving the undulatory signals along respective beams which are sufficiently narrow and intersect each other at a sufficient angle so that the beams converge and then overlap and then completely diverge from each other, sensing means for obtaining a Doppler signal having a frequency difference between the two frequencies, a frequency voltage converter for obtaining an electrical quantity proportional to the frequency of the Doppler signal, a first circuit which issues signals only when the electrical quantity exceeds a predetermined value, a second circuit which issues a signal only when the level of the Doppler signal exceeds a predetermined value, and an AND circuit for issuing a signal only when both the first and second circuits issue signals, said transmitting antenna and said receiving antenna being vertically displaced relative to each other and producing the beams so that they spread horizontally and so that the beams converge vertically and then overlap vertically and then completely diverge from each other vertically.

Claim 19

A potential collision detecting device, comprising a generator for generating an undulatory signal having a first frequency, a first transmitting antenna for radiating said undulatory signal, a first receiving antenna having a receiving axis intersecting the radiation axis of the first transmitting antenna within a predetermined region and adapted to receive reflected signals having a second frequency, said first transmitting and receiving antennas being vertically displaced relative to each other, said first transmitting antenna and said first receiving antenna respectively radiating and receiving the undulatory signals along beams sufficiently narrow in the vertical direction and at a sufficient angle in the vertical direction so that the beams as a whole converge in the vertical direction and then overlap in the vertical direction and then diverge in the vertical direction so that no portion of the beams continue to overlap in the vertical direction, sensing means connected to each of said antennas for obtaining a first Doppler signal having the difference frequency between said two frequencies, a second transmitting antenna which radiates undulatory signals having the first frequency, a second receiving antenna having a receiving axis intersecting the radiation axis of said second transmitting antenna within a predetermined region and adapted to receive reflected undulatory signals having a third frequency, said second transmitting and receiving antennas being vertically displaced relative to each other, said seconD transmitting antenna and said second receiving antenna respectively radiating and receiving undulatory signals along beams which are sufficiently narrow in the vertical direction and intersect at a sufficient angle in the vertical direction so that the beams first converge in the vertical direction and then overlap in the vertical direction and then diverge in the vertical direction without an overlap in the vertical direction, second sensing means for obtaining a second Doppler signal having the difference frequency between said first and third frequencies, circuit means for obtaining a first electrical quantity proportional to the frequency of the first Doppler signal, second circuit means for obtaining a second electrical quantity proportional to the frequency of the second Doppler signal, said first and second circuit means each being connected to respective ones of said sensing means, a divider connected to said first and second circuit means for obtaining an electrical quantity proportional to the ratio of the first electrical quantity and the second electrical quantity, first comparator means connected to said divider for issuing signals only when the output of said divider is within a predetermined range, second comparator means connected to said first circuit means for issuing signals only when the first electrical quantity exceeds a predetermined value, third comparator means connected to said second circuit means for issuing signals only when the second electrical quantity exceeds a predetermined value, a first OR circuit connected to the outputs of said second and third comparator means for calculating the existence of outputs at either of said comparator means, a fourth comparator means connected to said first sensing means for deriving as output when the level of said first Doppler signal exceeds a predetermined value, fifth comparator means connected to said second sensing means for deriving an output when the level of the second Doppler signal exceeds a predetermined value, a second OR circuit connected to said fourth and fifth comparator means for passing the signals from either of said fourth or fifth comparator means, and an AND circuit connected to said first comparator means, said first OR circuit and said second OR circuit for issuing signals when output signals simultaneously appear at said first comparator means, said first OR circuit and said second OR circuit, said antennas radiating and receiving beams wider in the vertical direction than the horizontal direction so as to cause the overlaps formed by the beams to extend across the width of the conveyance but remain within the width of the conveyance.

Claim 20

A potential collision detecting device, comprising a generator for generating an undulatory signal having a first frequency, a first transmitting antenna for radiating said undulatory signal, a first receiving antenna having a receiving axis intersecting the radiation axis of the first transmitting antenna within a predetermined region and adapted to receive reflected signals having a second frequency, said first transmitting and receiving antennas being vertically displaced relative to each other, said first transmitting antenna and said first receiving antenna respectively radiating and receiving the undulatory signals along beams sufficiently narrow in the vertical direction and at a sufficient angle in the vertical direction so that the beams as a whole converge in the vertical direction and then overlap in the vertical direction and then diverge in the vertical direction so that no portion of the beams continue to overlap in the vertical direction, sensing means connected to each of said antennas for obtaining a first Doppler signal having the difference frequency between said two frequencies, a second transmitting antenna which radiates undulatory signals having the first frequency, a second receiving antenna having a receiving axis intersecting the radiation axis of said second transmitting antenna within a predetermined region and adapted to receive reflected undulatory signals having a third frequency, said second transmitting and receiving antennas being vertically displaced relative to each other, said seconD transmitting antenna and said second receiving antenna respectively radiating and receiving undulatory signals along beams which are sufficiently narrow in the vertical direction and intersect at a sufficient angle in the vertical direction so that the beams first converge in the vertical direction and then overlap in the vertical direction and then diverge in the vertical direction without an overlap in the vertical direction, second sensing means for obtaining a second Doppler signal having the difference frequency between said first and third frequencies, circuit means for obtaining a first electrical quantity proportional to the frequency of the first Doppler signal, second circuit means for obtaining a second electrical quantity proportional to the frequency of the second Doppler signal, said first and second circuit means each being connected to respective ones of said sensing means, a divider connected to said first and second circuit means for obtaining an electrical quantity proportional to the ratio of the first electrical quantity and the second electrical quantity, first comparator means connected to said divider for issuing signals only when the output of said divider is within a predetermined range, second comparator means connected to said first circuit means for issuing signals only when the first electrical quantity exceeds a predetermined value, third comparator means connected to said second circuit means for issuing signals only when the second electrical quantity exceeds a predetermined value, a first OR circuit connected to the outputs of said second and third comparator means for calculating the existence of outputs at either of said comparator means, a fourth comparator means connected to said first sensing means for deriving as output when the level of said first Doppler signal exceeds a predetermined value, fifth comparator means connected to said second sensing means for deriving an output when the level of the second Doppler signal exceeds a predetermined value, a second OR circuit connected to said fourth and fifth comparator means for passing the signals from either of said fourth or fifth comparator means, and an AND circuit connected to said first comparator means, said first OR circuit and said second OR circuit for issuing signals when output signals simultaneously appear at said first comparator means, said first OR circuit and said second OR circuit, said antennas radiating and receiving beams wider in the vertical direction than the horizontal direction so as to cause the overlaps formed by the beams to extend across the width of the conveyance but remain within the width of the conveyance.

Claim 21

A system as in claim 1, further comprising output means for producing an actuating signal, barrier means for producing a safety barrier at locations in the conveyance where passengers are expected to strike the conveyance in the event of a collision, said barrier means being actuated by said output means.

Claim 22

A system as in claim 1, wherein said transmitting means and said receiving means define the patterns at such an angle that the sensitivity region formed thereby is completely bounded.

Claim 23

A vehicle for carrying passengers, comprising structure means having a front and a rear end, electrically actuable safety means mounted on the structure for selectively inserting a barrier between passengers and the structure in the event of a collision of the vehicle, transmitting means mounted on the front of said structure for transmitting undulatory radiation along a pattern having defined bounds, receiving means mounted on the front of said structure for receiving reflected and undulatory radiation along a second radiation pattern having defined bounds and intersecting the first pattern at a sufficient angle so as to define with the bounds of the patterns at the intersection of the patterns a sensitivity region, said transmitting means and said receiving means transmitting and receiving the undulatory radiation Along the patterns so that the patterns first converge and then overlap and then stop overlapping and diverge without overlap, detecting means responsive to said receiving means and said transmitting means for responding to frequencies received by said receiving means different from the frequency by said transmitting means and producing a signal when the difference exceeds a predetermined difference, output means connected to said detecting means and responsive to the thus produced signal and connected to said safety means for producing an actuating signal actuating said safety means, said transmitting means having a transmitting antenna transmitting the undulatory radiation along the pattern, said receiving means having a receiving antenna vertically aligned with the transmitting antenna and receiving the reflected undulatory radiation along the second radiatisn pattern, the second radiation pattern intersecting the first radiation pattern at a vertical angle, the antennas transmitting and receiving the undulatory radiation along the patterns so that the patterns first converge vertically and then overlap vertically and then stop overlapping vertically and diverge without overlap vertically, said antennas producing bounds so the overlap is wider horizontally than vertically.

Claim 24

A vehicle for carrying passengers, comprising structure means having a front and a rear end, electrically actuable safety means mounted on the structure for selectively inserting a barrier between passengers and the structure in the event of a collision of the vehicle, transmitting means mounted on the front of said structure for transmitting undulatory radiation along a pattern having defined bounds, receiving means mounted on the front of said structure for receiving reflected and undulatory radiation along a second radiation pattern having defined bounds and intersecting the first pattern at a sufficient angle so as to define with the bounds of the patterns at the intersection of the patterns a sensitivity region, said transmitting means and said receiving means transmitting and receiving the undulatory radiation Along the patterns so that the patterns first converge and then overlap and then stop overlapping and diverge without overlap, detecting means responsive to said receiving means and said transmitting means for responding to frequencies received by said receiving means different from the frequency by said transmitting means and producing a signal when the difference exceeds a predetermined difference, output means connected to said detecting means and responsive to the thus produced signal and connected to said safety means for producing an actuating signal actuating said safety means, said transmitting means having a transmitting antenna transmitting the undulatory radiation along the pattern, said receiving means having a receiving antenna vertically aligned with the transmitting antenna and receiving the reflected undulatory radiation along the second radiatisn pattern, the second radiation pattern intersecting the first radiation pattern at a vertical angle, the antennas transmitting and receiving the undulatory radiation along the patterns so that the patterns first converge vertically and then overlap vertically and then stop overlapping vertically and diverge without overlap vertically, said antennas producing bounds so the overlap is wider horizontally than vertically.

Claim 25

A system as in claim 1, wherein the patterns first converge vertically, then overlap vertically and then stop overlapping vertically and diverge vertically. 3

Claim 26

A system as in claim 1, wherein said transmitting means including first and second transmitting antennas, said receiving means including a first receiving antenna vertically aligned with said first transmitting antenna and a second receiving antenna vertically aligned with said second transmitting antenna, said patterns from said transmitting means each having two portions each portion defined by one of said transmitting antennas, said patterns of said receiving means having two portions each portion being formed by one of said receiving antennas, said transmitting means and said receiving means forming two overlap portions, said first transmitting and receiving antennas forming the first overlap portion and said second transmitting and receiving antennas forming the second overlap portion, said overlap portion extending only along the dimension of the conveyance transverse to the direction of the patterns from the antennas, the patterns extending from the antennas substantially in the direction forward of the conveyance.

Claim 27

A system as in claim 1, wherein the region extends only up to a finite distance from the conveyance and back toward the conveyance.

Claim 28

An apparatus as in claim 23, wherein objects within the region closer to the conveyance than said distance reflect radiation from said transmitting means to said receiving means, and objects outside of the region and beyond said distance fail to reflect radiation from said transmitting means to said receiving means.

Claim 29

A system as in claim 24, wherein said distance is less than several car lengths.

Claim 30

A system as in claim 24, wherein said distance is less than one car length.

Claim 31

A system as in claim 1, wherein the portion of the region more remote from the conveyance than the remainder of the region is less than one car length.

Claim 32

A system as in claim 16, wherein said beams stop overlapping and begin to diverge less than one conveyance length from the conveyance.