Tool bar

A tool bar, comprising a head part, a tail part, a pipe connection assembly, a backstop mechanism and a bushing member;

• the head part and the tail part are connected with each other by the pipe connection assembly;
• the bushing comprises a cone section and a cylinder section;
• one end of the head part passes through the cylinder section and connected to an inner thread of the cone section;
• the outer side of the cone section is configured to secure with a tool head;
• an external thread is provided on an outer surface of the cylinder section;
• the backstop mechanism comprises an intermediate member and a lock cap;
• the intermediate member is a hollow cylinder;
• the lock cap is a hollow cylindrical structure, with an internal thread provided on an inner wall of the lock cap at one end, and a shoulder provided at an end mouth on the other end;
• the intermediate member is fitted into an interior of the lock cap;
• the intermediate member and the lock cap together are fitted over the head part;
• the intermediate member tightly abuts against an outer surface of the head part;
• the internal thread on the lock cap is coupled with the external thread on the cylinder section;
• the shoulder abuts against an outer end face of the intermediate member;
• the pipe connection assembly comprises an inner bush, an outer bush, a lock bush and an intermediate bush;
• the inner bush comprises a first diameter bush and a second diameter bush, wherein the first diameter bush has a greater diameter than the second diameter bush;
• the first diameter bush is connected to one end of the bushing member away from the head part;
• one end of the outer bush is connected to one end of the tail part;
• the intermediate bush is fitted over the second diameter bush;
• the outer bush is fitted over the second diameter bush;
• an end face of the outer bush is jointed with an end face of the intermediate bush;
• the lock bush is fitted over the intermediate bush and the outer bush;
• an end of the lock bush is connected to the outer bush by thread connection;
• a stop collar is provided on the intermediate of the inner wall of the lock bush;
• when the lock bush is fitted over the intermediate bush and the outer bush, the stop collar is located between the intermediate bush and the first diameter bush;
• both the bushing member and the inner bush are solid members acting as extensions;
• a stop step is provided on an inner surface of the intermediate member;
• a plurality of open notches are provided on a side wall of the intermediate member;
• the open notches are spaced along the circumference of the side wall of the intermediate member and extend from the end to the center;
• a plurality of elongate planes are provided on the outer surface of the head part corresponding to the intermediate member;
• the elongate plane is matched with the stop step;
• a first teeth is provided on an outer end face of the cylinder section facing toward the intermediate member along the circumference of the cylinder section;
• a second teeth is provided on an inner end face of the intermediate member facing toward the cylinder section;
• the lock cap is thread connected with the cylinder section;
• and the second teeth is coupled with the first teeth.