Signaling device for scoring gunnery target practice

Claim 1

IN A DEVICE FOR PRODUCING SIGNALS THAT CAN BE USED TO OBTAIN INDICATIONS OF ACCURACY OF AIM DURING TARGET PRATICE: A TARGET PLATE OF SUBSTANTIALLY RIGID VIBRATION TRANSMITTING MATERIAL, DEFINING AN AREA IN WHICH SHOTS ARE TO BE PLACED; MEANS FOR SUPPORTING THE TARGET PLATE IN A POSITION NORMAL TO A LINE OF TARGET PRATICE FIRE, SAID SUPPORTING MEANS ENGAGING ONLY A SMALL PORTION OF THE TARGET PLATE SO AS TO PERMIT SHOCK WAVES TO TRAVEL UNIMPEDED THROUGH THE TARGET PLATE; A DIRECTIONAL VIBRATION RESPONSIVE TRANSDUCER FOR GENERATING AN ELECTRICAL SIGNAL IN RESPONSE TO A VIBRATION IMPULSE ALONG ONE AXIS OF THE TRANSDUCER, AND WHICH IS SUBSTANTIALLY NONRESPONSIVE TO VIBRATION IMPULSES ALONG OTHER AXES; AND RIGID VIBRATION TRANSMITTING MEANS SECURING THE TRANSDUCER TO AN EDGE PORTION OF THE TARGET PLATE WITH THE TRANSDUCER SO ORIENTED THAT ITS SAID ONE AXIS IS PARALLEL TO THE PLANE OF THE TARGET PLATE, SO THAT THE TRANSDUCER PRODUCES AN ELECTRICAL SIGNAL ONLY WHEN A PROJECTILE STRIKES THE TARGET PLATE AND THEREBY PROPAGATES AN EDGEWISE TRAVELING SHOCK WAVE THERETHROUGH, AND SO THAT THE TRANSDUCER IS NONRESPONSIVE TO VIBRATIONS NORMAL TO THE PLANE OF THE TARGET PLATE, SUCH AS THOSE DUE TO AIR SHOCK WAVES FROM PROJECTILES THAT PASS NEAR THE TARGET PLATE WITHOUT STRIKING IT.