The present invention is relates to a fiber reinforced resin screw 10, 20 shaped using a resin composition containing reinforcing fiber in a resin. A pitch of threads has a length of 1.5 to 2 times of a standard pitch corresponding to an outer diameter of the threads prescribed in standards of a metric coarse screw, a unified coarse screw and a unified fine screw. An average fiber length of the reinforcing fiber is 1 to ⅓ times of the pitch of the threads in the fiber reinforced resin screw. A content rate of the reinforcing fiber is in a range of 20 to 80%. In this way, the fiber reinforced resin screw to have improved is provided in the strength of the thread.

The present invention is relates to a fiber reinforced resin screw 10, 20 shaped using a resin composition containing reinforcing fiber in a resin. A pitch of threads has a length of 1.5 to 2 times of a standard pitch corresponding to an outer diameter of the threads prescribed in standards of a metric coarse screw, a unified coarse screw and a unified fine screw. An average fiber length of the reinforcing fiber is 1 to ⅓ times of the pitch of the threads in the fiber reinforced resin screw. A content rate of the reinforcing fiber is in a range of 20 to 80%. In this way, the fiber reinforced resin screw to have improved is provided in the strength of the thread.

Various embodiments include a fastening unit for fastening a tendon to a system. The fastening unit comprises: a head with a first opening; a shaft with a second opening and an external thread; and a channel extending from the first opening along the head to the second opening at least partly along the shaft. The external thread and the channel in each case accommodate the tendon.

Various embodiments include a fastening unit for fastening a tendon to a system. The fastening unit comprises: a head with a first opening; a shaft with a second opening and an external thread; and a channel extending from the first opening along the head to the second opening at least partly along the shaft. The external thread and the channel in each case accommodate the tendon.

A bolt for peeling a coating film of the present invention includes notch parts 6 for peeling a coating film, the notch parts being formed over a plurality of pitches at top parts of screw threads in a male screw part 3 formed in a shaft part 2. The bolt is characterized in that the respective notch parts 6 formed over the plurality of pitches are arranged to be greatly inclined at an angle of 40° to 50° to an axial line 12 of the shaft part 2. Since the respective notch parts can be rolled sequentially, it is possible to form the notch parts 6 to be deeper and sharper than conventional ones and to enhance the coating film peeling performance. Also, the coating film peeled can be discharged efficiently as compared with conventional cases.

A male fastener, female fastener, and a plunger that is adapted to secure the female fastener to the male fastener, and to prevent unwanted loosening of the female fastener from the male fastener. The male fastener includes a shaft that may optionally include a plurality of protruding elements that extend outwardly from an external surface of the shaft. The protruding elements may be radially positioned in rows around a circumference of the shaft, to create a channel between the rows of protruding elements. The channel is adapted to receive a corresponding thread located within an aperture of the female fastener. The plunger is adapted to be inserted into a trench located between a set of protruding elements (or into multiple trenches located between multiple protruding elements). The plunger prevents the female fastener from rotating around the shaft in a direction towards the bottom portion of the male fastener.

A sand resistant screw connector assembly can be used on the telescoping legs of a tripod assembly. The screw connector may use a trapezoidal thread, such as an Acme thread, for the male and female screw connectors. Such a thread design has been found to help push sand out to assist in cleaning. Therefore, when a tripod is designed using a screw connector having trapezoidal threads, the tripod may be well-suited for use in sandy environments, such as beaches, playgrounds, or the like. Various trapezoidal thread standards may be utilized, including JIS B0216, JIS B0217, JIS B0218, JIS B0222, ANSI B1.5 and ANSI B1.8, for example. The sand resistant screw connector may be used in other application where sand may pose a problem, including beach umbrellas, lawn furniture, beach games, and the like.

A sand resistant screw connector assembly can be used on the telescoping legs of a tripod assembly. The screw connector may use a trapezoidal thread, such as an Acme thread, for the male and female screw connectors. Such a thread design has been found to help push sand out to assist in cleaning. Therefore, when a tripod is designed using a screw connector having trapezoidal threads, the tripod may be well-suited for use in sandy environments, such as beaches, playgrounds, or the like. Various trapezoidal thread standards may be utilized, including JIS B0216, JIS B0217, JIS B0218, JIS B0222, ANSI B1.5 and ANSI B1.8, for example. The sand resistant screw connector may be used in other application where sand may pose a problem, including beach umbrellas, lawn furniture, beach games, and the like.

The die forming process includes first passing a circular coarse thread cutter over the forming surface of the die at an angle away from parallel to a side edge matching a pitch for coarse threads to be formed by the die. In a first cutting step, the coarse thread cutter forms upper portions of crests in the forming surface of the die. In a further step, a fine thread cutter is then utilized to cut portions of the root of the dual threaded die, leaving a bridge within the root. The fine thread cutter is angled relative to the crests formed in the first step. The fine thread cutter cuts at a variable depth as the fine thread cutter advances along the root between the crests to form two flanks on sides of the bridge within the root.

The present disclosure relates to a screw connection comprising a support component, an additional component and a screw to fasten the support component to the additional component. The support component has a tube made of thermoplastic foam to accommodate the screw in a friction and positive fit. The screw has a blunt-edged thread, enabling the screw to compress the foam in the tube as it is driven in. The ratio of the inner diameter of the tube to the diameter of the screw depends on the degree of foaming of the tube and decreases as the degree of foaming increases. In comparison to conventional screws, the threads of the screw of the present disclosure penetrate less deeply into the foam or they displace it, preventing damage to the tube while enabling a tight fit.