Method and apparatus for softness testing

Claim 3

The method according to claim 1 in which said steps of sensing and evaluating include the steps of selecting a predetermining ultrasonic frequency range of said sound energy, frequency converting said sound energy in said ultrasonic frequency range into an audio frequency range and indicating the level of energy converted to said audio frequency range.

Claim 4

The method according to claim 2 in which the step of indicating said level includes transducing said energy in said audio frequency range into an audible signal.

Claim 5

The method according to claim 1 in which said steps of sensing and evaluating include the steps of selecting a predetermined frequency range of said sound energy and producing said electrical signal with an amplitude representative of the level of said sound energy.

Claim 6

Apparatus for testing softness of paper fabrics and other flexible materials which comprises: flexing means for flexing a portion of said fabric, means for advancing said portion of said fabric between said flexing means, so that sound energy is produced in accordance with relative softness of the fibers in the fabric, means for detecting said sound energy and producing an electrical signal having a characteristic representative of the level of said sound energy; and means for evaluating said characteristic.

Claim 7

Apparatus for testing softness of paper fabrics and other flexible materials which comprises: flexing means for flexing a portion of said fabric, means for advancing said portion of said fabric between said flexing means, so that sound energy is produced in accordance with relative softness of the fibers in the fabric, means for detecting said sound energy and producing an electrical signal having a characteristic representative of the level of said sound energy; and means for evaluating said characteristic.

Claim 8

Apparatus according to claim 5 in which said means for evaluating said characteristic includes means for selecting a predetermined frequency band of said sound energy and means for indicating the level of the selected frequency sound energy.

Claim 9

Apparatus according to claim 5 wherein said portion of said fabric is strip-formed, said means for flexing is mounted in a sound-proof chamber having an entrance and an exit portion, said advancing means comprises means for continuously driving said strip from said entrance to said exit portion at a constant rate.

Claim 10

Apparatus according to claim 5 wherein means for flexing comprises a plurality of small-radius rods of low friction material, rigidly mounted within the chamber. 9. Apparatus according to claim 5 wherein said means for continuously driving comprises a constant speed driving motor, a first friction drive roller connected to said motor, and a second friction drive roller, engaging with said first roller, said drive rollers being adapted for feeding said strip of fabric through said means for flexing.

Claim 11

Apparatus according to claim 8 wherein said chamber comprises a box having a hinged-type cover, said rods comprise a first set of parallel rods rigidly mounted within the box and a second set of parallel rods rigidly mounted within the cover, each rod of the second set being designed to fit to a space between two adjacent rods of said first set of rods at the closed position of said cover.

Claim 12

Apparatus according to claim 5 wherein means for detecting said ultrasonic signal and generating a high frequency electrical signal comprises a high frequency microphone and preamplifier.

Claim 13

Apparatus according to claim 5 including means for converting said frequency electrical signal to an audible signal comprising a band pass filter, a local oscillator, a mixer connected to the output of said band pass filter and of said local oscillator and a low pass filter connected to the output of said mixer.

Claim 14

Apparatus according to claim 12 wherein an amplifier is connected between said mixer and said low pass filter.

Claim 15

Apparatus according to claim 5 wherein means for evaluating variations in a sound signal comprises a signal level measuring instrument and loudspeaker.

Claim 16

Apparatus for testing softness of paper fabrics and the like which comprises: a housing having a cover movable to open and closed position; a first set of parallel rods rigidly mounted within the housing; a second set of rods parallel with those of the first set, rigidly mounted within said cover, the rods of said second set being designed to fit in the spaces between adjacent rods of said first set at said closed position of the cover, said rods being of low-friction material; means for advancing a strip of the fabric to be tested between said first and second set of rods whereby the strip is forced to bend over one and under the other set of rods thus generating a sound signal; means for detecting said sound signal and converting it to an electrical signal; and means for indicating the level of said electrical signal.

Claim 17

Apparatus for testing softness of paper fabrics and the like which comprises: a housing having a cover movable to open and closed position; a first set of parallel rods rigidly mounted within the housing; a second set of rods parallel with those of the first set, rigidly mounted within said cover, the rods of said second set being designed to fit in the spaces between adjacent rods of said first set at said closed position of the cover, said rods being of low-friction material; means for advancing a strip of the fabric to be tested between said first and second set of rods whereby the strip is forced to bend over one and under the other set of rods thus generating a sound signal; means for detecting said sound signal and converting it to an electrical signal; and means for indicating the level of said electrical signal.