A buckle structure is adapted to connect a strap. The buckle structure has a connecting port. The connecting port has a connecting member for connecting the strap. An extending portion extends from a side of the connecting port. The extending portion has an opening for the strap to pass through. The strap passes through the opening to enter the connecting port and connect the connecting member.

A plug for a buckle includes an attachment portion configured to be attached to the predetermined members; a pair of leg portions protruding in the same direction away from the attachment portion; extending portions extending in a direction from tip end portions of the pair of leg portions toward base end portions of the leg portions; a coupling piece coupling the base end portions of the pair of leg portions; a first restricting portion that is located at an intermediate portion of the coupling piece and faces extending ends of the extending portions; and second restricting portions that protrude from two sides in a longitudinal direction of the coupling piece in a manner of sandwiching the first restricting portion, extend in a protruding direction of the leg portions, and face inner side surfaces of the leg portions.

A buckle assembly formed of a male buckle portion and a female buckle portion. The female buckle portion has a top wall, a bottom wall, side walls, and a cavity between the top wall and the bottom wall and a locking slot in each of the side walls. The male buckle portion has a base, two locking legs and two intermediate legs between the locking legs. The locking legs extend through the locking slots in the female portion, and locking pawls at the end of the locking legs engage the edges of the locking slots to secure the buckle portions together. The free ends of the locking legs are connected to the free ends of the intermediate legs by a retaining member, so that forces acting on the locking legs are transferred to the intermediate legs by the retaining members.

A protective helmet including a helmet shell for at least partially covering the head of a helmet wearer, and a holding strap arrangement arranged on the helmet shell for holding the helmet shell on the head of the helmet wearer. The holding strap arrangement includes a chin strap connected to the helmet shell, a first closure part connected to the helmet shell, and a second closure part connected to the chin strap and can be brought into closed connection with the first closure part, with a closure being formed. The closure automatically opens in a first closed position if a predetermined opening tensile force acts between the closure parts, and the closure parts separate from each other. In a second closed position, the first closure part and the second closure part are always in closed connection with each other irrespective of a tensile force acting between the closure parts.

A tool belt (1) comprises a belt strap (2) and a belt buckle (3), wherein the belt buckle (3) comprises a male (5) and a female part (7). The male part (5) comprises a latch plate (27) and the female part (7) comprises a female interface (9) for receiving the latch plate (27). The latch plate (27) is attached to a first end (2a) of the belt strap (2) and the female part (7) is attached to a second end (2b) of the belt strap (2), and the female part (7) comprises a locking mechanism (15) adapted for connection and disconnection of the latch plate (27) to or from the female interface (9), and a length adjustment mechanism (17) adapted for adjustment of the length of the belt strap (2).

A buckle with a string adjustment portion includes a plug and a socket. The plug includes: a tightening string member attachment portion configured to slidably lock a string member and adjust a length of the string member; and leg portions which are inserted into and engaged with the socket. The socket includes a fitting portion including an insertion opening. An insertion hole through which the string member is inserted is formed to penetrate the tightening string member attachment portion, and a portion connecting the leg portions side of the insertion hole serves as a second bar. The second bar is located on an insertion direction side of the leg portions with respect to a position where an end portion of the plug and the insertion opening of the socket are abutted against each other, in a state where the leg portions are engaged with the socket.

A buckle assembly formed of a male buckle portion and a female buckle portion. The female buckle portion has a top wall, a bottom wall, side walls, and a cavity between the top wall and the bottom wall and a locking slot in each of the side walls. The male buckle portion has a base, two locking legs, a center leg, and two intermediate legs between the locking legs and the center leg. The locking legs extend through the locking slots in the female portion, and locking pawls at the end of the locking legs engage the edges of the locking slots to secure the buckle portions together. Each locking leg is connected to a flexible retaining member that prevents the locking legs from being flexed outwardly beyond a predetermined point. The intermediate legs and/or the retaining members form stop surfaces that prevent the locking legs from being flexed inwardly beyond a point of contact with the stop surfaces.

A detachable belt connector system (100), for the detachable connection of belt ends (770, 775), includes a first connector element (110) with a first connection area (112) and a first belt fastening area (116) and a second connector element (120) with a second connection area (122) and a second belt fastening area (126). The first and second connection areas are configured to be connected to one another in a detachably with a positive-lock. The belt ends can be fastened at the belt fastening areas via a corresponding permanent fastening mechanism. The first belt fastening area and/or the second belt fastening area are configured such that they have a predetermined breaking region (140), by means of which an irreversible break takes place at the belt fastening area having the predetermined breaking region when a predefined limit pulling force (150) is applied at the detachable belt connector system.

A buckle includes two coupling modules coupled separably to each other. Each of the coupling modules includes a main unit including a hook member and a coupling member that has a retaining portion, and an operating member having an operating portion and a pushing portion. The hook member of each of the coupling modules is engaged with the retaining portion of the other one of the coupling modules. The operating portions of the operating members of the coupling modules are movable toward each other, during which the pushing portion of each of the coupling modules pushes the hook member of the other one of the coupling modules to disengage said hook member from the retaining portion of the coupling module.

A buckle has a main body, a strap retaining bar connected to the main body, two locking legs formed as separate pieces from the main body and pivotably connected to the main body; and a spring formed of two L-shaped sections disposed between the two locking legs. The spring is attached to both of the locking legs, and exerts a force against the locking legs when they are pressed inward toward each other. The spring keeps the locking legs in an outwardly tensioned position, but does not let the legs flex outwardly in an unlimited manner, since the spring is directly connected to the legs. The spring allows the main body and locking legs to be formed of an inflexible material, such as metal. The locking legs are separate pieces from the main body and are connected to the main body via a pivot pin or other hinged mechanism.