US 4,051,681 AGranted

Unitary roof bolt assembly

OwnerLee William Yarosinventor

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Abstract

A unitary roof bolt assembly which obviates the necessity for a two or more component system. The assembly includes a standard elongated roof bolt which is desired to be adhesively secured within a bore hole of a rock-like roof structure or the like. A flexible bag or sack contains a conventional quick-setting adhesive resin and hardening material and is circumflexed about the elongated stem of the roof bolt so as to surround and encompass same. Securing means are provided for maintaining the flexible sack and bolt as a unitary structure prior to insertion of the assembly into the bore hole, whereafter the flexible sack is ruptured upon rotation of the bolt and upon contact with the innermost wall of the bore hole to release the adhesive. In a preferred embodiment, the flexible bag comprises a long thin tubular sack, having a diameter on the order of the diameter of the elongated stem of the roof bolt, and is wrapped about the stem of the bolt in a close packed spiral fashion. A reduced diameter spiral sack extends from the distal end of the bolt so as to be rupturable upon contact with the innermost wall of the bore hole.

Claims7

Dependent claims

A unitary roof bolt assembly mountable within a bore hole of predetermined depth in an excavation roof desired to be strengthened comprising:

a bolt having an elongated stem, a head integral with said stem at one end thereof;
and said stem having a distal end opposite said head and a length which is somewhat but not substantially less than the depth of said bore hole which reaches to an innermost wall thereof,
a rupturable flexible sack means having a first generally uniformly disposed unbroken portion encompassing said stem in extending from said head to said distal end, and which continues to a relatively narrower generally uniformly disposed unbroken portion covering said distal end and extending therebeyond, said sack means containing a curable adhesive along said extents of said first and said second portions thereof, and being secured to said stem by means wrapped about said first and said second portions until ruptured,
whereby an insertion of said bolt within said bore hole which pressure contacts said second portion of said sack means against said innermost bore hole wall provides a substantial force rupturing said sack means so as to fixedly secure said bolt within said bore hole with said adhesive thus released therebetween.

1 more element

Dependencies are inferred from the claim text.