Apparatus for measuring the stiffness characteristic of structural adhesives

Claim 1

An apparatus adapted to be used in conjunction with a second apparatus having the same structure but of a mirror image configuration for the measurement of the shear stiffness characteristic of structural adhesives so as to enable the accurate stress analysis of an adhesive bond comprising A. a first frame having an aperture therein, B. a second frame, C. a first plate spring fully fixed at one of its ends to the upper section of said first frame and at the other of its ends to the upper section of said second frame, D. a second plate spring fully fixed at one of its ends to the lower section of said first frame and at the other of its ends to the lower section of said second frame, E. a first supporting member on said second frame extending movably into said aperture, F. a second supporting member on said first frame comprising a third spring which is positioned above said first supporting member, pivotably rotates on an axis and is adjacent said aperture, G. a first sensor point fixedly mounted on said second supporting member within the confines of said aperture, H. second and third sensor points fixedly mounted on said first supporting member within the confines of said aperture, I. bracket means attached to said second frame, J. adjusting means attached to the top and bottom of said first frame, K. a linear, variable, differential transformer comprising a coil and a core, the coil of which is supported by said bracket means and positioned within the space between said first and second frames and the core of which is affixed to said adjusting means and positioned within the hollow of said coil, L. first locking means adjacent said adjusting means and adapted to prevent accidental movement thereof, M. interactive, second locking means positioned adjacent to said first and second frames and adapted, when engaged, to minimize flexing of said first and second plate springs, N. mounting plate spring means affixed to the first frame at its middle, extending beyond the vertical edges of said first frame and having attaching means within the extending portions thereof, said sensor points being positioned such that said first point is above said second and third points and moves pivotably around an imaginary line drawn parallel to said second and third sensor points, said second and third points are in the same horizontal plane with respect to said first frame, and the tips thereof touch substantially the same vertical plane.

Claim 2

An apparatus adapted to be used in conjunction with a second apparatus having the same structure but of a mirror image configuration for the measurement of the shear stiffness characteristic of structural adhesives so as to enable the accurate stress analysis of an adhesive bond comprising A. a first frame having an aperture therein, B. a second frame, C. a first plate spring fully fixed at one of its ends to the upper section of said first frame and at the other of its ends to the upper section of said second frame, D. a second plate spring fully fixed at one of its ends to the lower section of said first frame and at the other of its ends to the lower section of said second frame, E. a first supporting member on said second frame extending movably into said aperture, F. a second supporting member on said first frame comprising a third spring which is positioned above said first supporting member, pivotably rotates on an axis and is adjacent said aperture, G. a first sensor point fixedly mounted on said second supporting member within the confines of said aperture, H. second and third sensor points fixedly mounted on said first supporting member within the confines of said aperture, I. bracket means attached to said second frame, J. adjusting means attached to the top and bottom of said first frame, K. a linear, variable, differential transformer comprising a coil and a core, the coil of which is supported by said bracket means and positioned within the space between said first and second frames and the core of which is affixed to said adjusting means and positioned within the hollow of said coil, L. first locking means adjacent said adjusting means and adapted to prevent accidental movement thereof, M. interactive, second locking means positioned adjacent to said first and second frames and adapted, when engaged, to minimize flexing of said first and second plate springs, N. mounting plate spring means affixed to the first frame at its middle, extending beyond the vertical edges of said first frame and having attaching means within the extending portions thereof, said sensor points being positioned such that said first point is above said second and third points and moves pivotably around an imaginary line drawn parallel to said second and third sensor points, said second and third points are in the same horizontal plane with respect to said first frame, and the tips thereof touch substantially the same vertical plane.