Snap hook
A hook and an eye are integral with and located at opposite longitudinal ends of a body. The hook includes a tip spaced from the body and defining a mouth for attachment of the hook to a ring or other object. A lock pin mounted in the body moves axially between a closed position engaging the tip of the hook and an open position. The body has a flat, easily gripped shape with a button at one side movable in a transverse direction. A cam system translates transverse button movement into axial movement of the lock pin, and provides a decreasing force-displacement characteristic. The hook is designed to break to prevent user injury in the event of excessive force, and includes a ramp surface facilitating detachment of the hook.
1. A snap hook comprising:
a body having a longitudinal axis and first and second axially spaced ends;
a hook at said first end of said body, said hook having an axially extending shank, a bail and a tip spaced from said body and defining a hook entrance mouth between said tip and said body; and
a lock pin mounted in said body for axial movement toward said tip to a closed position and away from said tip to an open position;
said snap hook being characterized by:
a button mounted on said body for movement in a direction transverse to said axis; and
a cam system between said button and said lock pin for translating transverse button movement into axial lock pin movement, said cam system including a curved cam surface providing a decreasing button force requirement throughout at least most of the range of button motion as said lock pin moves toward said open position;
said lock pin including a segment within said body extending in a direction transverse to said axis, and said cam system including a cam surface on said button engaging said segment.
2. A snap hook as claimed in claim 1 further comprising a spring in said body urging said lock pin toward said closed position.
3. A snap hook as claimed in claim 1 further comprising an eye at said second end of said body.
4. A snap hook as claimed in claim 3 , said eye being fixed with respect to said body.
5. A snap hook as claimed in claim 4 , said eye comprising a slot extending through said body.
6. A snap hook as claimed in claim 4 , said eye and said hook being integral and of one piece with said body.
7. A snap hook as claimed in claim 1 , said button including a manually engageable portion located closer to said second end of said body than to said first end of said body.
8. A snap hook as claimed in claim 1 , said hook including a ramp portion extending from said bail toward said body and to said tip at an oblique angle relative to said axis.
9. A snap hook as claimed in claim 8 , said angle being between forty-five and ninety degrees.
10. A snap hook comprising:
a body having a longitudinal axis and first and second axially spaced ends;
a hook at said first end of said body, said hook having an axially extending shank a bail and a tip spaced from said body and defining a hook entrance mouth between said tip and said body;
a lock pin mounted in said body for axial movement toward said tip to a closed position and away from said tip to an open position; and
a button operably coupled to said lock pin for moving said lock pin toward said open position;
said snap hook being characterized by:
said button being mounted on said body for movement in a direction transverse to said axis; and
a cam system between said button and said lock pin for translating transverse button movement into axial lock pin movement;
said button comprising a lever having a first and a second end, said first end being pivotally attached to said body at a location closer to said first end of said body than to said second end of said body.
11. A snap hook as claimed in claim 10 , said lock pin including a segment within said body extending in a direction transverse to said axis, and said cam system including a cam surface on said button engaging said segment.
12. A snap hook comprising:
a body having a longitudinal axis and first and second axially spaced ends;
a hook at said first end of said body, said hook having an axially extending shank, a bail and a tip spaced from said body and defining a hook entrance mouth between said tip and said body;
a lock pin mounted in said body for axial movement toward said tip to a closed position and away from said tip to an open position;
a button operably coupled to said lock pin for moving said lock pin toward said open position; and
said snap hook being characterized by:
a spring carried within said body and directly engaging said lock pin to urge said lock pin toward said closed position
said button being mounted on said body for movement in a direction transverse to said axis; and
a cam system between said button and said lock pin for translating transverse button movement into axial lock pin movement;
said button comprising a lever pivotally mounted relative to said body.