Damage Detection

Abstract

Damage detection apparatus for use on a normally vertical post supporting a remote signalling device including a radio transmitter, comprising an electric generator having output terminals connected to the transmitter, a source of mechanical energy, and means for applying mechanical energy from the source to cause operation of the generator and the transmitter when the orientation of the post departs from the vertical by a predetermined amount.

Description

This invention relates to apparatus for detecting and indicating a change in orientation, with respect to a vertical reference axis, of a support upon which the apparatus is mounted.

For years, there has existed an unsatisfied need for a simple batteryless wireless signalling system for use in locations where electrical power is either not available or is subject to failure under conditions in which the signalling system is most needed. The former situation is present in modern superhighway systems, which at present must be constantly patrolled by radio-equipped vehicles for the motorists' protection. The latter situation arises in newly developed residential areas remote from urban centers, where fire protection must be provided in the form of fire alarm boxes which at present require an expensive independent underground wiring system for protection from the elements.

This need has been fulfilled by the manually powered, wireless electrical signalling systems described in U.S. Pat. No. 3,621,398 to Willis. The elimination of wires in such a signalling system, however, makes it difficult to send test signals to the various transmitter units (typically pole-mounted emergency boxes spaced along superhighways) to verify the continued operability of the units which are exposed to damage via vehicular collision with the units' supporting posts.

In view of the foregoing, it is a principal object of the present invention to provide apparatus which will detect and indicate a change in orientation of a support, while being reliable in operation and inexpensive to manufacture and install.

It is a further object to provide such apparatus which requires neither batteries nor an external source of energy for its operation.

It is an additional object to provide such apparatus which is rugged in construction and easy to reset.

These and other objects of the invention are accomplished by providing damage detection apparatus for use on a normally vertical post supporting a remote signalling device including a radio transmitter, comprising an electric generator having output terminals connected to said transmitter, a source of mechanical energy, and means for applying mechanical energy from said source to cause operation of said generator and said transmitter when the orientation of said post departs from the vertical by a predetermined amount.

Still further objects, features, and advantages will appear from the following description of a preferred embodiment taken together with the accompanying drawing.

Referring to the drawing, the apparatus 10 is mounted on a support 12 in the form of a vertical post, such as is suitable for supporting a highway remote alarm system including a suitable radio transmitter 13 having an antenna 15. A frame member 14 of the apparatus 10 is provided with straps 16 which encircle the post 12 and are drawn tightly to grip the post. A suitable enclosure (not shown) for the apparatus may be secured to the frame 14 or the post 12.

An electric generator 18, having output leads 20 connected to radio transmitter 13, is mounted such that its shaft 22 is vertically disposed. Gear 24 is keyed to shaft 22 and is rotatably supported on a member 26 which is secured to the frame 14. Gear 28, engaged with gear 24, is secured to shaft 30 and is also mounted for rotation with respect to member 26. Spool 32 is also secured to shaft 30. Storage spool 34 is mounted for rotation with respect to member 26 and includes an upwardly projecting axial portion 36 having a square opening 38 in its upper face. Spiral spring 40 is formed from a flat web of metal and has its opposite ends secured to spools 32 and 34 respectively. The lower, downward facing surface of spool 32 has a 45.degree. latch detent (not visible) spaced outwardly from shaft 30.

Elongated member 42 is vertically disposed in opening 44 of an arm 46 which projects from the main body of frame 14. The upper end of member 42 has a ball 48 partially protruding therefrom and upwardly biased by means of internal spring 50. The lower end 52 of member 42 is smoothly rounded with a 0.25 inch radius. Reset handle 54 is secured to member 42 by means of rod 56 which passes through member 42 intermediate ball 50 and opening 44.

Pendulum 58 comprises weight 60 and arm 62 which is mounted in projection 64 of frame member 14 in a ball joint support 66. The upper portion of arm 62 is of reduced diameter and has a smoothly rounded upper end 66 having a radius of three thirty-seconds inch.

Crank 70 is separable from the remainder of the apparatus and has a lower shaft portion 72 having a cross section of appropriate shape and size to fit snugly within opening 38 on spool 34.

The operation of the apparatus is as follows. The spring 40 is a constant force spring which in its unstressed configuration assumes a spiral configuration around spool 32. When the lower end 72 of crank 70 is inserted into opening 38 on spool 34 and the crank is rotated clockwise, the spring 40 is wound onto spool 34 in a spiral of opposite sense from that which it assumes in its unstressed configuration. The potential energy of the stressed spring 40 is stored by means of the spring loaded ball 48 being seated in the latch detent on the lower surface of spool 32, thereby preventing rotation of spool 32. Upon withdrawal of ball 48 from the latch detent, the potential energy of spring 40 as wound on spool 34 is converted into kinetic energy of rotation of spool 32 and gear 28 as the spring 40 produces such rotation in assuming its unstressed configuration as wound upon spool 32. The nature of spring 40 as described above produces a constant velocity of rotation of the gear 28 for virtually the entire duration of the rotation.

This rotation of gear 28 causes rotation of gear 24 and consequent operation of generator 18 which provides an output on leads 20 for the operation of radio transmitter 13. Since the vertically slidable member 42 is supported by pendulum 58 (surfaces 52 and 68 being in contact) with ball 48 received in the latch detent on spool 32, the application of the energy stored in the spring to cause generation of a signal is restrained. If the post 12 should deviate from its vertical orientation, the fact that pendulum 58 will tend to remain in a truly vertical orientation will cause relative rotation between surfaces 52 and 68. After sufficient displacement of post 12 the rotation between surfaces 52 and 68 will be sufficient to permit member 42 to slide with respect to the frame 14 under the influence of spring 50 and/or gravitational attraction so as to withdraw ball 48 from the latch detent on spool 32. Thus, a sufficient departure from the predetermined orientation of post 12 (i.e., vertical) will release the mechanical energy stored in spring 40 and operate the electrical generator 18 to cause the generation of a radio signal from transmitter 13. This signal, which may be coded by conventional techniques, will be transmitted to a central location for detecting the signal so transmitted thus enabling repair and/or emergency equipment to be directed to the particular post 12 which has been damaged or knocked over.

As will be evident to those skilled in the art, from geometrical considerations, the relation of the radii of curvature of surfaces 52 and 68 will be the dominant factor which determines how much tilt of post 12 (or, equivalently, the departure from axial alignment between member 42 which remains parallel to the post 12 and arm 62 which remains vertical) will be required to cause disengagement of surfaces 52 and 68 with consequent application of the stored energy in spring 40 to produce an electrical output on leads 20 for operating transmitter 13. For the values given above, a 15.degree. departure of post 12 from the vertical in any direction will cause the disengagement of surfaces 52 and 68.

The apparatus as described is reset by lifting reset handle 54 to cause the re-engagement of surfaces 52 and 68, the use of crank 70 to rewind the spring 30 from spool 32 onto spool 34, and the insertion of ball 48 in the latch detent on spool 32.

While a particular embodiment has been described in detail, other embodiments will occur to those skilled in the art and are within the following claims.

Claims

What is claimed is:

1. Apparatus for use on a normally vertical post supporting a remote signalling device including a radio transmitter, comprising an electric generator having output means connected to said transmitter, a source of mechanical energy, and means for applying mechanical energy from said source to cause operation of said generator and said transmitter when the orientation of said post departs from the vertical by a predetermined amount.

2. Apparatus as claimed in claim 1 wherein said means for applying energy comprises

a first member movable between first and second positions and disposed, when in said first position, to restrain the application of energy from said energy source to said generator, said first member being biased toward said second position,

a second member supported for pivotal movement about a horizontal axis between first and second positions with respect to said post,

said second member in its first position retaining said first member in its first position and said second member in its second position releasing said first member for movement to its second position under the influence of said bias.

3. Apparatus as claimed in claim 2 wherein said first member includes a rounded surface having a first predetermined radius, said second member includes a rounded surface having a second predetermined radius in contact with said rounded surface of said first member when each said member is in its respective first position.

4. Apparatus as claimed in claim 3 wherein said second member comprises a pendulum including an elongated arm and a weighted lower end, said rounded surface of said second member being at the upper end thereof.

5. Apparatus as claimed in claim 4 wherein said source of mechanical energy comprises a spring normally maintained in a stressed configuration.

6. Apparatus mountable on a support for detecting a deparature from a predetermined orientation of said support comprising an electric generator, a source of mechanical energy, and means for applying energy from said source to cause operation of said generator when said departure exceeds a predetermined magnitude, said means comprising

a first member movable between first and second positions and disposed, when in said first position, to restrain the application of energy from said energy source to said generator, said first member being biased toward said second position,

a second member supported for pivotal movement about a horizontal axis between first and second positions with respect to said support,

said second member in its first position retaining said first member in its first position and said second member in its second position releasing said first member for movement to its second postion under the influence of said bias.

7. Apparatus as claimed in claim 6 wherein said first member includes a rounded surface having a first predetermined radius, said second member includes a rounded surface having a second predetermined radius in contact with said rounded surface of said first member when each said member is in its respective first position.

8. Apparatus as claimed in claim 7 wherein said second member comprises a pendulum including an elongated arm and a weighted lower end, said rounded surface of said second member being at the upper end thereof.

9. Apparatus mountable on a support for detecting a departure from a predetermined orientation of said support comprising an electric generator, a source of mechanical energy, and means for applying energy from said source to cause operation of said generator when said departure exceeds a predetermined magnitude, said means comprising

a first member movable between first and second positions and disposed, when in said first position, to restrain the application of energy from said energy source to said generator, said first member being biased toward said second position,

a second member supported for pivotal movement about a horizontal axis between first and second positions with respect to said support,

said second member in its first position retaining said first member in its first position and said second member in its second position releasing said first member for movement to its second position under the influence of said bias.

10. Apparatus as claimed in claim 9 further including a radio transmitter connected to said generator.

11. Apparatus mountable upon a support responsive to a departure from a predetermined orientation of said support comprising

an electric generator,

a source of mechanical energy comprising a spring normally maintained in a stressed configuration,

means for applying energy from said spring to cause operation of said generator when said departure exceeds a predetermined magnitude, said means comprising

a first member movable vertically between first and second positions and disposed, when in said first position, to restrain the application of energy from said spring to said generator, said first member being biased towards said second position, said first member including a rounded surface having a first predetermined radius at its lower vertical end;

a second member comprising a pendulum supported for pivotal movement about a horizontal axis between first and second positions with respect to said support, said second member in its first position retaining said first member in its first position and said second member in its second position releasing said first member for movement to its second position under the influence of said bias, said second member including an elongated arm, a weighted lower end, and a rounded surface at its upper end, said rounded surface, when each of said first and second members is in its first position, being in contact with said rounded surface of said first member.