A positioning structure of clamp may include a fixed clamp and a guiding rod, and the fixed clamp has a clamping portion and a connecting portion respectively at an upper portion and a lower portion thereof, and a guiding hole penetrates through the connecting portion. The guiding rod coupled into the guiding hole comprises a plurality of first through holes thereon, a first engaging hole and a second engaging hole respectively penetrating through two lateral sides of the connecting portion are respectively communicated with the guiding hole. A plurality of lock holes are formed at the lateral side of the connecting portion same as the second engaging hole. A positioning unit, connected to the connecting portion through the first engaging hole, the second engaging hole, and the lock holes, comprises a clamping block, an engaging block, a positioning bolt, a positioning block, a clamping plate and a rotating member.

A support for a mitre joint uses two wedging mechanisms disposed at a characteristic angle. Each wedging mechanism is arranged to locate inside a hollow rail, such as within an extruded hollow beam. The wedging mechanism can be operated from outside the joint in order to clamp the mechanism in position. The mechanism has a self centering capability to assist in accurately locating the rails relative to each other.

A ratchet woodworking clamp with a universal adaptive clamping block includes a fixed clamp arm and a movable clamp arm, the fixed clamp arm and the movable clamp arm being both provided with an arc-shaped notch, and the arc-shaped notch being matched and connected with a movable connecting member, wherein a middle portion of the arc-shaped notch is provided with a semi-spherical or spherical groove recessed inwardly, one side of the movable connecting member is a circular connecting end, which is in matched connection with the arc-shaped notch, and the circular connecting end is provided with a spherical or semi-spherical convex structure in an inward direction, which is matched and connected with the groove in the middle portion of the arc-shaped notch.

A ratchet woodworking clamp with a universal adaptive clamping block includes a fixed clamp arm and a movable clamp arm, the fixed clamp arm and the movable clamp arm being both provided with an arc-shaped notch, and the arc-shaped notch being matched and connected with a movable connecting member, wherein a middle portion of the arc-shaped notch is provided with a semi-spherical or spherical groove recessed inwardly, one side of the movable connecting member is a circular connecting end, which is in matched connection with the arc-shaped notch, and the circular connecting end is provided with a spherical or semi-spherical convex structure in an inward direction, which is matched and connected with the groove in the middle portion of the arc-shaped notch.

In one or more arrangements, a bar clamp system is presented. The system includes an elongated bar, an end stop assembly operably connected to and moveable along the elongated bar, and a handle assembly operably connected to and moveable along the elongated bar. The end stop assembly includes an actuator, a first locking mechanism, and a second locking mechanism. The handle assembly includes a clamp actuator, a release actuator, and a clamp mechanism operably connected to the clamp actuator and the release actuator. In one or more arrangements, the end stop assembly and handle assembly each have a clamp plate having a clamping surface. To facilitate clamping, the end stop assembly and handle assembly can be repositioned on the elongated bar with the clamping surfaces facing toward each other. To facilitate spreading, the clamping surfaces can be positioned facing away from each other.

A clamp device has first and second jaws movable relative to one another for clamping an object therebetween. A clamp sensor operatively connected to one of the jaws generates a clamping signal representative of a clamping force urging the first and second jaws towards one another. A display is arranged to display a value proportional to the clamping signal which is representative of the clamping force between the first and second jaws. A motor for driving movement of the second jaw relative to the first jaw is operated by a controller that responds to operator commands in a manual control mode and/or which automatically drives the motor so as to maintain the clamping signal measured by the clamp sensor within a prescribed threshold range to apply a constant clamping force between the first and second jaws under an automated control mode.

A support for a mitre joint uses two wedging mechanisms disposed at a characteristic angle. Each wedging mechanism is arranged to locate inside a hollow rail, such as within an extruded hollow beam. The wedging mechanism can be operated from outside the joint in order to clamp the mechanism in position. The mechanism has a self centering capability to assist in accurately locating the rails relative to each other.

A clamping handle assembly that is usable with woodworking tools that enables a user to suitably maintain and secure various types of workpiece and/or stock to a woodworking tool during a woodworking project. The clamping handle assembly comprises of a handle. The clamping handle assembly also comprises of a threaded shaft that is operably engaged with the handle, said threaded shaft is adapted to engage with a woodworking tool. The clamping handle assembly also comprises of a clamp block that is operably engaged with the threaded shaft, said clamp block is adapted to apply a clamping force to a workpiece. In addition, various types of clamp blocks may be included in a clamping handle assembly to suitably maintain and secure various types of workpiece and/or stock to a woodworking tool during a woodworking project.

A clamping force visualization clamp and a clamping force visualization clamp combination device. The clamping force visualization clamp includes a clamping force visualization device, the clamping force visualization device includes a first clamping body (01) for clamping an object, the first clamping body (01) is telescopically assembled on a base (14), an elastic element (110) is provided between the first clamping body (01) and the base (14), a clamping force scale (11) and a reading indicator (15) are respectively provided on the first clamping body (01) and the base (14), when the first clamping body (01) clamps the object, the elastic element (110) measures a clamping force, and the reading indicator (15) points to the clamping force scale (11) for reading, so that the magnitude of the clamping force can be intuitively seen and read during clamping, thereby achieving accurate clamping. A clamp including the clamping force visualization device is also involved.

A clamp head adapter (100), including: an adapter body (102); a slot (104) disposed on a first side (106) of the adapter body and configured to receive and secure therein a clamp head (24); and a groove (110) recessed into a body surface (112) of the adapter body opposite the first side. The groove includes a vertex (130); a first bevel angle (132) between a normal line (134) normal to the body surface and a first line (136) between the vertex and a first corner (138) of the groove, and a second bevel angle (150) between the normal line and a second line (152) between the vertex and a second corner (154) of the groove. The first bevel angle and the second bevel angle together form a groove angle (156) that is less than 90 degrees.