An engaging structure for a hand tool includes a main body provided with a mounting element, six drive portions, six receiving portions, two first arcuate faces, a second arcuate face, a first radius, a second radius, a first distance, and a second distance. Each of the six receiving portions has an arcuate concave shape and is arranged between one of the two first arcuate faces of one of the six drive portions and one of the two first arcuate faces of another one of the six drive portions. Each of the six receiving portions forms a first circle and a third radius. The mounting element has a center forming a second circle forming a first hexagon having six sides. The center is served as an axis defining a second hexagon. The second hexagon is less than the first hexagon.

An engaging structure includes a main body including a first side, a second side, a third side, and a fourth side. The first side, the third side, the fourth side, and the second side construct a hexagon. The hexagon has an axis, a fourth length, and a vertical line. The first side is provided with a first recess and a first face. The first recess is situated at a left side of the vertical line. The vertical line passes the first face. The first recess is provided with a first arcuate face and a second arcuate face. The second side is provided with a second recess and a second face. The second recess is situated at a left side of the vertical line. The vertical line passes the second face. The second recess is provided with a first corner and a second corner.

A blind bolt and tool is used for fastening a bolt through a hole in a structure when only one side of the structure is accessible. A receiver is formed on the tip end of a bolt shaft opposite from a bolt head. Internal threads are formed within the receiver proximate an outward end, and a hex socket is formed in the inward end of the receiver. External threads and a guide are formed on a tip of the tool, and the external threads mate with the internal threads in the receiver to hold the bolt during installation. A hex key on one end of the tool engages the hex socket in the receiver so that the tool may impose a torque on the bolt when a nut is being tightened on the bolt. In another embodiment, a splined tip is formed on the end of the bolt. The tip is designed to shear off when a sufficient torque is applied. Also, a shim is configured to fit between structures held together by the blind bolt.

A step bolt connector and bolt assembly creates steps on a structure for accommodating a worker's boot. A first threaded bore is formed in a cylindrical end of a step bolt connector and this first threaded bore is threaded onto an exposed bolt on a structure. A sight hole extends from the exterior of the connector to the inward end of the first threaded bore for visually checking to see if the bolt is adequately attached in the first bore. A recess is formed in the cylindrical end and the recess is dimensioned to fit over fastening nut on the exposed bolt on the structure. When the first threaded bore is screwed onto the exposed bolts on the structure, the recess at least partially surrounds shields and protects the fastening nut on the exposed end of the bolt. A second threaded bore is formed in a second end (a truncated conical end) of the connector, and a step bolt is secured in the second threaded bore. The step bolt is dimensioned so that the step bolt when fastened to the connector forms a step on the structure having a length greater than the width of the workers boot. In this manner, a convenient step is formed on the structure for use in climbing the structure to perform repairs, maintenance or modifications.

A carburetor with a fuel adjustment tamperproof valve assembly and specialized tools for adjusting the valve assembly. A needle valve is received in a recess in a carburetor body with a passage open to the exterior of the body and a cylindrical surface of the passage. A valve head with a cylindrical exterior surface is received in the passage with a slight clearance between them. The specialized tools are engageable with the head to adjust the valve by rotating it.

A carburetor with a fuel adjustment tamperproof valve assembly and specialized tools for adjusting the valve assembly. A needle valve is received in a recess in a carburetor body with a passage open to the exterior of the body and a cylindrical surface of the passage. A valve head with a cylindrical exterior surface is received in the passage with a slight clearance between them. The specialized tools are engageable with the head to adjust the valve by rotating it.

A socket having a working end with a work piece aperture that is adapted to receive a work piece and an opposing drive end adapted to engage a torque application tool. The socket includes a biasing member adapted to apply a biased frictional force to the work piece received in the work piece aperture and including first and second opposing ends, where the first end is restricted from moving in the radial direction, and the second end includes a bent portion and is restricted from moving in the axial direction, and a groove formed in an internal surface of the work piece aperture. The bent portion engages the groove.

Expandable spinal implants, systems and methods are disclosed. An expandable spinal implant may include a first endplate, a second endplate, and a moving mechanism that is operably coupled to the first and second endplates. The moving mechanism may include a wedge, a first sliding frame and a second sliding frame disposed on opposite sides of the wedge, a screw guide housing a rotatable first set screw and a rotatable second set screw opposite the first set screw. The first set screw may be operably coupled to the second sliding frame and the second set screw may be operably coupled to the wedge. The moving mechanism may operably adjust a spacing between the first and second endplates upon simultaneous rotation of the first and second set screws and operably adjust an angle of inclination between the first and second endplates upon translating the first set screw or second set screw.

The disclosure relates to a screwdriver attachment for screws, which has a first shaft section with a first longitudinal axis, and a second shaft section with a second longitudinal axis. The second shaft section is coupled to the first shaft section via a linking disk. The first shaft section has a free end with which the screws are turned. The first shaft section and second shaft section are connected to one another by a spring element, which aligns the first shaft section in a starting position in which the first longitudinal axis and the second longitudinal axis are aligned coaxially. Screws can be readily turned with the screwdriver attachment according to the disclosure, even if there is a certain offset between the axes.

An engaging structure for a hand tool includes a main body provided with a mounting element having six drive portions and six receiving portions. Each of the drive portions includes a first face, a second face, and a third face. A first intersection point is located at an intersection of the first face and the second face. A second intersection point is located at an intersection of the first face and the third face. Each of the receiving portions is an arcuate concave face. The mounting element has a first hexagon. The first face of each of the drive portions coincides with each of the sides of the first hexagon. The first hexagon has six first angled corners. The first arc of each of the six receiving portions is situated outside of each of the six first angled corners.