US Patent 7264284 Door catch

A door catch includes a back plate having two laterally symmetric sleeves formed on a front face thereof. An elastic check member is mounted in a rear end of each sleeve to replace a conventional screw to confine a steel ball and a spring in the sleeve, so that the spring normally pushes the steel ball forward to partially project from a front open end of the sleeve and the elastic check member backward to firmly close the rear end of the sleeve. The steel balls projected from the two sleeves of the back plate together firmly clamp between them a stop post correspondingly mounted on a movable door leaf.