Methods for making curved pieces from continuous metal elements are provided. Such methods include advancing a continuous metal element through a calendering station such that each length of the element assumes a pre-established curvature; stopping advancement of the element after a curved length thereof has passed through a wrap-bending station located downstream of the calendering station; wrap-bending the length of the element located at the station, while simultaneously conveying the curved portion to a stretch-bending station; stretch-bending the curved portion; resuming advancement of the element until the wrap-bent length is at a cutting station; and cutting the element in the wrap-bent length, thus producing the desired curved piece. Curved pieces produced by such methods are also provided.

A design method of a metal mask, a manufacturing method of the metal mask and a computer-readable storage medium are provided. The design method of a metal mask includes: calculating amounts of deformations of the metal mask in two directions perpendicular to each other based on a stretching force of the metal mask in use and deformation properties of the metal mask in the two directions; and compensating the deformations of the metal mask in the two directions by compensation amounts for the deformations, which are identical and opposite to the amounts of the deformations of the metal mask in the two directions, respectively.

A design method of a metal mask, a manufacturing method of the metal mask and a computer-readable storage medium are provided. The design method of a metal mask includes: calculating amounts of deformations of the metal mask in two directions perpendicular to each other based on a stretching force of the metal mask in use and deformation properties of the metal mask in the two directions; and compensating the deformations of the metal mask in the two directions by compensation amounts for the deformations, which are identical and opposite to the amounts of the deformations of the metal mask in the two directions, respectively.

The disclosure provides a portable light. The portable light includes a housing having a front surface, a rear surface, and an internal space for receiving electronic components and a battery. The portable light also includes a chip-on-board (COB) assembly. The COB assembly includes a substrate, a matrix of individual light emitting diode (LED) chips mounted to the substrate, and an outer coating covering the matrix of LED chips. The front surface of the housing is curved in one direction and the COB assembly is correspondingly curved and mounted to the front surface, such that individual LED chips are positioned about the curve and orientated to direct light outwardly about the curve to provide a collective beam angle greater than 220 degrees. The portable light further includes a front lens cover to protect the COB assembly.

A NC machine for stretch bending and monitoring method for clamping force of round clamp thereof is invented, which includes a round head clamp, a hydraulic system and a clamping force monitoring device. The round head clamp includes a housing, an internal module arranged in the housing and a positioning member for positioning the internal module in the housing. The hydraulic system includes a hydraulic rod and a hydraulic ram for pushing the hydraulic rod. The clamping force monitoring device includes a sensor and a data processing module. The present invention is suitable for the workpiece of different shapes and sizes. In this invention, the clamping force can be adjusted in real time when it needs to be changed, and this not only can avoid the problems of excessive energy consumption, excessive clamping marks and damage of the workpiece, but also save energy and protect the workpiece.

A NC machine for stretch bending and monitoring method for clamping force of round clamp thereof is invented, which includes a round head clamp, a hydraulic system and a clamping force monitoring device. The round head clamp includes a housing, an internal module arranged in the housing and a positioning member for positioning the internal module in the housing. The hydraulic system includes a hydraulic rod and a hydraulic ram for pushing the hydraulic rod. The clamping force monitoring device includes a sensor and a data processing module. The present invention is suitable for the workpiece of different shapes and sizes. In this invention, the clamping force can be adjusted in real time when it needs to be changed, and this not only can avoid the problems of excessive energy consumption, excessive clamping marks and damage of the workpiece, but also save energy and protect the workpiece.

A method for precision forming by continuous free bending starts with establishing a correlation equation of a continuous axis f(x) to a bending radius R and determining a bending radius R at a real-time location in the axis. Based on the free bending technique, the method further involves establishing a correlation model of a real-time bending radius R of a tube to an eccentric distance U of a bending die and hence correlations of the equation of the axis to free bending parameters, and constructing a complete correlation model among f(x), R, U, and t based on a relational equation of an eccentric distance U to movement time t of the bending die to enable the precision forming of a complex component by continuous bending. Accordingly, the production efficiency can be improved.

A method for precision forming by continuous free bending starts with establishing a correlation equation of a continuous axis f(x) to a bending radius R and determining a bending radius R at a real-time location in the axis. Based on the free bending technique, the method further involves establishing a correlation model of a real-time bending radius R of a tube to an eccentric distance U of a bending die and hence correlations of the equation of the axis to free bending parameters, and constructing a complete correlation model among f(x), R, U, and t based on a relational equation of an eccentric distance U to movement time t of the bending die to enable the precision forming of a complex component by continuous bending. Accordingly, the production efficiency can be improved.

To suppress occurrence of stress corrosion cracking in a weld due to tensile residual stress generated in a web or a middle rib in case of bend forming of an aluminum alloy extrusion having the weld on the web or/and the middle rib. In bend forming of the aluminum alloy extrusion, a peak position of tensile residual stress generated in the middle rib exists in a region other than the vicinity of the weld. Since the peak position is away from the weld by a distance, tensile residual stress in the weld is reduced, making it possible to suppress occurrence of stress corrosion cracking.

An object of the present invention is to provide a bending die that has a simple configuration and is capable of bending a rod-shaped body in a three-dimensional XYZ direction quickly and reliably, the bending die comprising a pair of forming dies clamped in a Z direction, wherein the forming dies have, respectively, rod-shaped body-forming recess portions, and rod-shaped body guide portions for guiding a rod-shaped body to the rod-shaped body-forming recess portions, the rod-shaped body-forming recess portions are each formed into a shape with a semicircular cross section that defines, between the forming dies when clamping the forming dies, a long, cylindrical cavity for forming the rod-shaped body bent in a three-dimensional XYZ direction, and the rod-shaped body guide portions are each formed into a V-shape that spreads outward from both sides of each of the rod-shaped body-forming recess portions having a semicircular cross section.