The invention relates to a device for processing a workpiece, said device including the following features: a punch on one side of the workpiece, a die on the opposite side of the workpiece, and a conductive electric heating system for generating an electric current that flows through the workpiece starting from a component situated on one side of the workpiece outside of the punch to a component situated on the opposite side of the workpiece outside of the die.

The present invention discloses a chair tray and chassis, chassis forming method and chassis mounting structure of the same. The main points of its technical solution are that the chair chassis comprises a chassis body that is arranged with a mounting hole thereon for mounting a regulating knob. The edge at the position corresponding to the mounting hole of the chassis body is arranged with a flange. The structural strength and the fatigue strength of the chassis can be enhanced effectively by arranging the flange at the position corresponding to the mounting hole of the chassis, which avoids the occurrence of fracture at the perimeter of the mounting hole of the chassis during use or test and thus enables the thickness of the chassis to be reduced below 3 mm, reducing production material to a very large extent and saving production cost while also ensuring that it can pass the back pad fatigue test in the BIFMA standard. Additionally, the fact that the flange surrounds the mounting hole can increase the structural strength and the fatigue strength at the perimeter of the mounting hole of the chassis more all around with a better effect.

A tab is provided, which includes a body having first and second opposing ends, a nose portion disposed at or about the first end of the body, a lift portion disposed at or about the second end of the body of the tab, and a rivet receiving portion disposed proximate the nose portion. The rivet receiving portion includes a generally planar portion, a rivet hole having a perimeter, and an upturned portion extending upwardly from the generally planar portion about the perimeter of the rivet hole. The upturned portion reinforces the rivet hole and has an arcuate cross section profile. An integral rivet extends through the rivet hole and is staked to affix the tab to a can end. The upturned portion is devoid of any corners or edges both before and after the integral rivet is staked.

A tab is provided, which includes a body having first and second opposing ends, a nose portion disposed at or about the first end of the body, a lift portion disposed at or about the second end of the body of the tab, and a rivet receiving portion disposed proximate the nose portion. The rivet receiving portion includes a generally planar portion, a rivet hole having a perimeter, and an upturned portion extending upwardly from the generally planar portion about the perimeter of the rivet hole. The upturned portion reinforces the rivet hole and has an arcuate cross section profile. An integral rivet extends through the rivet hole and is staked to affix the tab to a can end. The upturned portion is devoid of any corners or edges both before and after the integral rivet is staked.

A heat exchanger and a method of manufacturing the same are provided. With the method, a tube may be inserted into a through hole formed in at least one fin coated with a filler metal, and the tube and a fin collar of the at least one fin may be joined through the filler metal by a brazing processing. A flange may not be formed on or at a top of the at least one fin collar, which protrudes vertically from a central longitudinal plane of the at least one fin. The tube may be made of aluminum (Al), and an interval between an outer circumferential surface of the tube and an inner circumferential surface of the fin collar of the at least one fin may be approximately 0.1 mm or less. Accordingly, contact resistance occurring when fabricating a fin-tube heat exchanger using a mechanical tube expansion method may be reduced, and heat transfer performance of the heat exchanger may be improved because grooves formed within the tube may not be deformed.

A punch and die assembly for a forming assembly for forming flared openings in commercial forming steel sheeting, includes a punch. The punch has a punching element having a base portion and a working portion that extends from a face of the base portion, the working portion defining a working edge with more than two substantially evenly spaced peaks and troughs for forming an opening in the steel sheeting during a working stroke. A flaring element is mountable on the base portion of the punching element, a side of the flaring element defining an arcuate flaring surface that tapers inwardly in the direction of the working stroke. A die supports the steel sheeting, the die having a die opening with a flared die face for facing the flaring surface of the flaring element such that the opening in the steel sheeting is flared by the flaring surface of the flaring element and the die face in the working stroke.

Stepwise bending in the method for manufacturing a vehicle suspension arm includes a first bending step and a second bending step. In the first bending step, preliminary bending is performed while holding a portion that composes a base portion of a body portion and a portion that composes first coupling portions in a workpiece W by a punch (first punch). In the second bending step, while holding of the portion that composes the first coupling portions by the first punch is released subsequently to the first bending step, bending is performed along a fold given by the first bending step while holding the portion that composes the base portion of the body portion by a punch (second punch).

Provided is a burring processing method, which is a method for forming a buffing processed portion including a raised portion and a curved portion in a metal component having a pilot hole formed therein, the method being characterized by including: a preforming step of enlarging a diameter of the pilot hole, moving an edge portion of the pilot hole relative to the metal component in a first direction of a thickness direction of the metal component in a first range around the pilot hole of the metal component, and forming the whole first range into a preformed portion raised from the metal component in the first direction; and a main forming step of deforming the preformed portion in a second direction opposite to the first direction, forming a second range on an outer diameter side of the preformed portion to have the same height as the first range in the first direction, and forming part of a third range on an inner diameter side of the preformed portion from the second range to be part of the curved portion and the raised portion.