US 4,758,031 AGranted

Retractable safety latch for cases

AssigneeThermodyne International Ltd.

InventorWalter C. Wolf

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Abstract

A retractable safety latch is disclosed and includes a base mounting member having perpendicular base walls, a draw bar guide attached to the mounting base member by a hinge, a draw bar having an arcuate hook on one end and an eccentrically positioned oblong hole on the other end slidably mounted on the draw bar guide, a rotatable shaft mounted on the draw bar guide and having an eccentrically mounted pin extending through the oblong hole for driving and retaining the draw bar in the draw bar guide, and a handle having a safety catch pivotably mounted on the rotatable shaft. Between the handle and the rotatable shaft is a spring for the purpose of biasing the handle in one direction with respect to the rotatable shaft so that when the latch is closed, the handle is in contact with the perpendicular base walls and the safety catch catches on one of the perpendicular base walls to prevent the rotatable shaft on which the handle is mounted from rotating and opening the latch. When the latch is open, the spring biased handle is forced into contact with the draw bar and a second spring mounted on the hinge coupled between the mounting base member and the draw bar guide will force the draw bar guide into a retracted flush position with respect to the case, which prevents the latch from protruding further than necessary from the case.

Claims6

Dependent claims

A retractable safety latch for use on a case, which includes a bottom shell having an edge extrusion and a top shell having a mating edge extrusion, that comprises:

a base member mounted on said bottom edge extrusion;
a perpendicular base wall mounted perpendicularly to said base member;
a draw bar guide having U-shaped flanges along its longitudinal edges attached to said base member by a hinge;
a draw bar having an arcuate hook on one end and an eccentrically positioned oblong hole in the other end slidably mounted between said U-shaped flanges on said draw bar guide;
a rotatable shaft mounted on said draw bar guide and having an eccentrically mounted pin extending through said eccentrically positioned oblong hole in said draw bar for driving said draw bar and retaining said draw bar in said draw bar guide and whereby said eccentrically mounted pin and said eccentrically positioned oblong hole operate together to allow said rotatable shaft to rotate through only about 180 degrees with 0 degrees rotation corresponding to an open position for said retractable safety latch with said draw bar fully extended and 180 degrees rotation corresponding to a closed position for said retractable safety latch with said draw bar retracted;
a handle pivotably mounted on said rotatable shaft;
and
a first spring between said handle and said rotatable shaft that biases said pivotably mounted handle always in one direction with respect to said rotatable shaft so that when said retractable safety latch is in a closed position with said arcuate hook attached to said mating edge extrusion, said handle is biased to be in contact with and resting on said perpendicular base wall, and so that when said retractable safety latch is in an open position, said handle is biased in the same direction with respect to said rotatable shaft and is in contact with said draw bar.

5 more elements

A retractable safety latch for use on a case, which includes a bottom shell having an edge extrusion and a top shell having a mating edge extrusion, that comprises:

a base member mounted on said bottom edge extrusion;
a draw bar guide having U-shaped flanges along its longitudinal edges attached to said base member by a hinge;
a draw bar having an arcuate hook on one end and an eccentrically positioned oblong hole in the other end slidably mounted between said U-shaped flanges on said draw bar guide;
a rotatable shaft mounted on said draw bar guide and having an eccentrically mounted pin extending through said eccentrically positioned oblong hole in said draw bar for driving said draw bar and retaining said draw bar in said draw bar guide and whereby said eccentrically mounted pin and said eccentrically positioned oblong hole operate together to allow said rotatable shaft to rotate through only about 180 degrees with 0 degrees rotation corresponding to an open position for said retractable safety latch with said draw bar fully extended and 180 degrees rotation corresponding to a closed position for said retractable safety latch with said draw bar retracted;
a handle pivotably mounted on said rotatable shaft;
and
a first spring between said handle and said rotatable shaft that biases said pivotably mounted handle always in one direction with respect to said rotatable shaft so that when said retractable safety latch is in a closed position with said arcuate hook attached to said mating edge extrusion, said handle is biased to be in contact with and resting on said base member, and so that when said retractable safety latch is in an open position, said handle is biased in the same direction with respect to said rotatable shaft and is in contact with said draw bar.

4 more elements

Dependencies are inferred from the claim text.