Abstract: Nondestructive testing of heat exchangers (12), such as a radiator, measures the percentage of good bonds between air centers and cooling tubes based on natural or resonant frequencies of the exchanger (12). The exchanger (12) is excited by an audio speaker (38) and measured for a first natural frequency in the center thereof by an accelerometer (44). The natural frequency is indicative of the percentage of good bonds in the center portion of the exchanger (12) based on the stiffness thereof. The audio speaker (38) is moved to an antinode of a higher frequency mode to measure a second natural frequency indicating the percentage of bonds at the edges and corners thereof. The resonant frequencies are compared to standards to determine the actual percentage of good bonds.

Abstract: An acoustic inspection method is disclosed for determining in a catalytic converter monolith substrate whether a ceramic coating was applied in a predetermined amount and uniformly to the surface of exhaust gas passages extending therethrough and whether the ceramic coating is blocking any of the passages. The method includes mounting the substrate in an acoustically sealed structure so as to form a throat communicating a speaker at an entrance end of the coated passages with an empty resonator cavity at an exit end of the coated passages and thereby form a Helmholtz resonator. The speaker is then driven to produce a continuous sound wave through the coated passages into the resonator cavity at a predetermined frequency approximately the natural frequency of the resonator to thereby produce oscillatory sound waves through the coated passages at the same frequency. The substrate is then reversely mounted and the previous step is repeated.

Abstract: Adjustable damping is provided for the seat bottom cushion of a vehicle seat of the type having a seat frame which is mounted at a stationary position on the vehicle floor. A resilient seat cushion is mounted upon the seat frame and is resiliently compressed relative to the frame by the static occupant load when the occupant sits upon the seat bottom cushion. Occupant movement causes the further resilient movement of the seat bottom cushion above and below the static vertical position. A scissors mechanism acts between the vehicle body and a plate attached to or embedded in the seat bottom cushion to translate the vertical movement of the seat bottom cushion into a horizontal movement of a portion of the scissors mechanism. An adjustable damping device such as a dash pot is operatively connected to the horizontally movable portion of the scissors mechanism whereby the vertical movement of the seat bottom above and below the static vertical position is adjustably damped to provide a desired occupant ride.

Abstract: There is disclosed an acoustic inspection method for determining whether the actual fluid flow path through a manufactured fluid flow system such as an evaporator core is of a prescribed length and thereby free of such manufacturing errors as cause a shortened or lengthened fluid flow path. The method comprises the steps of passing a test sound wave of predetermined frequency along the actual fluid flow path through the manufactured fluid flow system and comparing the phase angle of the test sound wave at the exit of the actual fluid flow path being inspected with that of a reference sound wave of the same frequency passing along the exactly prescribed fluid flow path length and on the basis that a difference in phase angle indicates that the fluid flow path being inspected is not of the prescribed length.

Abstract: A restraint table for a vehicle that is normally stored within a console located along one side of a passenger seat and is connected to the console by a hinge member which allows sequential movement of the restraint table about a pair of substantially perpendicular axes so that the restraint table assumes a position in front of an occupant seated in the passenger seat.