Bolt for conveyor belt fastener

A fastener for splicing end portions of conveyor belts having tough, rugged carcasses in which holes are preformed through the end portions for receiving bolts therethrough, the fastener including plates with apertures and cooperating with the bolt to clamp the plates on opposite surfaces of at least one of the end portions to be spliced, the fastener comprising:

• an elongate shank of the bolt having proximate and distal ends thereof and an axis along which the shank extends;
• an enlarged head portion at the proximate end of the shank for being seated in the aperture of one of the plates with the one plate and the bolt head resting on a support to orient the shank with its axis generally extending normal to the one plate;
• a plurality of threads having a predetermined maximum diameter formed on the shank adjacent the head portion and extending toward the distal end of the shank;
• a non-threaded lead-in portion at the distal end of the shank having a predetermined diameter less than the shank threads maximum diameter and a predetermined length from the distal end that allows the preformed hole in a belt end portion to be pushed over the shank from thereabove with a minimum of hang-ups on the shank threads;
• a nut having internal threads having a predetermined minimum diameter less than the shank threads maximum diameter and greater than the lead-in portion diameter for being threaded to the shank threads;
• and
• a transition area of the shank projecting portion between the lead-in portion and said upper threads and being sized relative to the nut threads minimum diameter so that with the nut released on the lead-in portion, the nut will slide axially down the shank along the predetermined length of the lead-in portion until a lower leading thread thereof abuts against the shank at the transition area thereof to define a nut resting location along the shank with the nut in position for proper threading onto the shank threads.

A conveyor belt splicing assembly for splicing belt end portions together;

• the splicing assembly comprising:
• a plurality of bolts each having an elongate shank with an enlarged head at one end thereof;
• a plurality of threads formed along each of the shanks of the bolts;
• upper and lower plates for being placed on opposite surfaces of a belt end portion, each of the plates having an aperture for receiving the bolt shanks therethrough with the bolt heads seating in the lower plate apertures;
• a projecting portion of each of the bolt shanks having a pilot portion free of threads and including the upper shank threads of the shank threads distal from the bolt head and immediately adjacent to the pilot portion, the projecting portion being sized for exposing the upper threads with the shank extending through the plate apertures and a preformed hole in the belt end;
• and
• a plurality of nuts having internal threads sized to provide clearance between the nut threads and the pilot portion and to be threaded to the shank threads, the nuts having a stopped state prior to prethreading thereof where sliding of the nuts along the pilot portion is arrested via a leading thread of the nut abutting an uppermost thread of the bolt shank in proper alignment for being threaded thereto that allows a splice installer to rapidly turn all of the stopped nuts to quickly generate a plurality of prethreaded nuts on the exposed upper threads of the projecting portions of the bolt shanks.

A conveyor belt splicing system for splicing end portions of conveyor belts together and creating high strength splices therebetween, the splicing system comprising:

• a pair of plates for being attached on opposite surfaces of the belts end portion, the pair of plates each including at least one aperture therein;
• a bolt having an elongate shank for being inserted through a preformed hole in a conveyor belt end portion, the bolt having an enlarged head at one end thereof for seating in the aperture of one of the plates;
• a plurality of threads on the shank having a predetermined maximum diameter;
• a lead-in portion of the shank having a surface free of threads spaced from the bolt head and extending toward the end of the bolt opposite to the bolt head end with the shank threads disposed between the lead-in portion and the bolt head, the lead-in portion having a predetermined diameter that is less than the shank threads predetermined maximum diameter to guide the shank during insertion through the belt end portion preformed hole minimizing the force required to push the shank therethrough;
• a nut having internal threads for being threaded to the shank threads;
• a template and a hole forming tool, the template having at least one guide hole having a predetermined diameter that is minimized in size relative to the predetermined maximum diameter of the shank threads and the tool being sized to fit through the template guide hole for creating the preformed hole sized substantially the same as the guide hole to keep the amount of belt material removed by the tool and clearance between the shank threads and the belt material about the preformed hole to a minimum for providing high strength belt splices.