Means for disabling a safety catch on a screw-threaded component
A disabling tab ( 100 ) for disabling an anti-disengagement or safety catch ( 80 ) such as on a connector ( 20 ) of a pedestal for elevated floors having mating internally and externally threaded components is disclosed. The safety catch ( 80 ) is a pivoted wedge shaped block defined at the lower end of an externally threaded component which defines a ramped portion ( 84 ) extending to a buttress end ( 86 ) facing the start of the external thread. In the internally threaded components, one thread also defines a buttress end ( 92 ). When the components are screwed together, the ramp ( 84 ) of the safety catch deflects inwards and passes the buttress end ( 92 ). When the components are unscrewed, the end ( 86 ) of the catch abuts the end ( 92 ) of the thread preventing the components from being unscrewed. The tab ( 100 ) includes a v-shaped end portion ( 106 ) comprising two arms—a thin ramped bridge portion ( 110 ) which in use fits over, the safety catch ( 80 ), and a second arm 108 which locates between the threads at the start of the thread of the externally threaded component. A shaft ( 100 ) extends away from end portion ( 106 ). In use, the bridge portion ( 110 ) disables the safety catch by guiding the buttress end ( 92 ) of the internal thread over the safety catch ( 80 ) while deflecting the safety catch inwards. The arms ( 110, 108 ) of the bridge portion are thin enough to pass between the external and internal threads without jamming.
1. A combination of an externally threaded component having a safety catch and a disabling tab, comprising:
the safety catch of the externally threaded component having a hinged flap and a face for engaging a buttress end of an internal thread of an internally threaded component, the face being disposed adjacent a start of an external thread of the externally threaded component and separated therefrom by a gap, the disabling tab including a flexible bridging portion at least partly covering the hinged flap and spanning the gap between the face of the catch and start of the external thread of the externally threaded component, the bridging portion having a first arm which fits over the hinged flap, and a second arm, of lesser height than the first arm, located between the face of the catch and the start of the external thread, at the start of the external thread of the externally threaded component, including a shaft extending from the bridging portion, towards the interior of the externally threaded component, wherein the first arm extends from a first side of the shaft and the second arm extends from a second side of the shaft, opposite to the first side a side arm extending from the first side of the shaft and spaced from the first arm, wherein a free end of the safety catch is located between the first arm and the side arm.
2. A combination as claimed in claim 1 wherein the first and second arms join at a y-shaped apex.
3. A combination as claimed in claim 1 further including a grip defined at an opposite end of the shaft to the bridging portion.
4. A combination as claimed in claim 1 wherein the bridging portion has a thickness around 0.4 mm.
5. A combination as claimed in claim 1 wherein the disabling tab is made from a plastic material.
6. A combination as claimed in claim 5 wherein the plastics material is polypropylene.
7. A combination as claimed in claim 1 wherein the externally threaded component is a component of a pedestal jack.
8. A combination of an externally threaded component having a safety catch and a disabling tab comprising:
the safety catch of the externally threaded component having a hinged flap and a face for engaging a buttress end of an internal thread of an internally threaded component, the face being disposed adjacent a start of an external thread of the externally threaded component and separated therefrom by a gap, the disabling tab including a flexible bridging portion at least partly covering the hinged flap and spanning the gap between the face of the catch and start of the external thread of the externally threaded component, the bridging portion having a first arm which fits over the hinged flap, and a second arm, of lesser height than the first arm, located between the face of the catch and the start of the external thread, at the start of the external thread of the externally threaded component, including a shaft extending from the bridging portion towards the interior of the externally threaded component, wherein the first arm extends from a first side of the shaft and the second arm extends from a second side of the shaft, opposite to the first side, a side arm extending from the first side of the shaft and spaced from the first arm, and a grip defined at the opposite end of the shaft to the bridging portion, the disabling tab being made from a plastic material and the bridging portion of the tab having a thickness of less than 0.5 mm.