Abstract: In order to load and discharge pieces of sheet metal automatically onto and from a machine tool having a horizontal table movable along a first horizontal axis, a horizontal discharge table and a horizontal loading table are provided in positions in which the tables are side by side and substantially aligned with the horizontal plane of the table of the machine tool. An unprocessed piece of sheet metal to be supplied to the machine tool is placed on the loading table. Initially, the piece-holding table of the machine tool is positioned beside the discharge table. The piece of sheet metal on the piece-holding table is transferred to the discharge table by being slid on the bearing surfaces of the tables in the direction of a second horizontal axis perpendicular to the first axis. The table of the machine tool is then moved to a position in which it is beside the loading table.

Abstract: In a punching processing method, a punch chip having a roller shape is arranged in a punch chip holder rotatable around the vertical axis and can be rotated around the horizontal axis. A die chip having a roller shape is arranged in a die chip holder rotatable around the vertical axis and can be rotated around the horizontal axis. Punching processing of a work is performed, in cooperation with the punch chip and the die chip, by moving the work in the horizontal direction in a state in which the work is held between the punch chip and the die chip. Further, a roll forming die used in this punching processing method is also proposed. Accordingly, it is possible to perform various kinds of punching processings for a short time without causing any seam and easily perform processings of a circle and a curve in addition to processing of only a straight line.

Abstract: A die for a press brake is formed with: a first V-shaped groove (43A) extending in a longitudinal direction and on an upper surface thereof; a second V-shaped groove (43B) extending in the same way in parallel to the first V-shaped groove; a plurality of first engage slots (45A) arranged on a lower surface thereof in parallel to the first V-shaped groove by a predetermined distance (A) from a central bottom line of the first V-shaped groove; and a plurality of second engage slots (45B) arranged in the same way in parallel to the second V-shaped groove by the same predetermined distance from a central bottom line of the second V-shaped groove. The first and second engage slots (45A, 45B) are used in common for alignment of the first and second V-shaped grooves (43A, 43B) with a punch (7) mated to the die.

Abstract: In an upper tool, a stripper plate (35) is disposed movably up and down at a lower end portion (13a) of a punch guide (13) for housing a punch (27) also movably up and down, via a shock damping member (33). Further, the shock damping member (33) is formed into an annular body disposed so as to enclose an annular gap (X) formed between the lower end portion (13a) of the punch guide (13) and the upper surface (65) of the stripper plate (35). The upper tool can reduce noise sound generated during punching processing, and further prevent chips produced during punching processing from adhering onto the workpiece and the shock damping member, thus protecting the workpiece from being scratched by the chips and further improving the life time of the shock damping member.

Abstract: In an upper tool for a press brake formed with an inclined surface (9S) narrowed upwardly at an upper portion thereof and an engage groove (9G) formed under the inclined surface (9S). The inclined surface (9S) is brought into contact with an inclined surface of an upper tool clamp member (11), when the upper tool is clamped between an upper tool holder body (5) and an upper tool clamp member (11), in such a way that clamping force can be further increased when the upper tool is engaged with a die (63). Further, in an upper tool holder apparatus for a press brake, the pivotal upper tool clamp member (211) is formed with an engage projection (211P) for engaging a drop prevention groove (205G) formed in the upper tool (205).

Abstract: In a bender (e.g., press brake), work (plate material) can be bent by a bending tool composed of a pair of punch and die. A position detector (17) mounted on a movable side of the bending tool generates a limit point pulse (ULi) whenever the tool reaches a limit point. A timer (29) measures a time interval between the two limit point pulses (ULi). A time compare discriminate section (31) compares the time interval measured by the timer with a reference time interval (TR), and further discriminates the current bending as a trial bending when the time interval is longer than the reference time but as an actual bending when shorter than the reference time. Further, an arithmetic section 33 calculates a sum total number of times of the bending and the sum total time period spent in the bendings, separately in both of the trial and actual bendings. The obtained bending data are displayed or recorded to obtain an accurate man-hour in the bending processing.

Abstract: A punching die includes a punch body, a punch guide fitted on the punch body movably up and down with respect to the punch body, a punch head provided on a top portion of the punch body, and a gaseous spring provided between the punch body and the punch guide for pushing the punch guide downwardly with respect to the punch body. The gaseous spring is cylindrical and fitted on the punch body detachably, and includes a device for restricting a maximum length of the gaseous spring.

Abstract: An upper tool for a press brake is removably attachable to an upper tool holding device mounted on an upper table of the press brake. The upper tool includes a mounting portion and a projection portion, both adjacent a first end of the upper tool, a work processing portion adjacent a second end of the upper tool, a clamping surface and a sliding surface, extending divergingly from the projection portion, and a contact surface extending substantially perpendicular to the sliding surface. The clamping surface extends along the length of the upper tool beyond the contact surface.

Abstract: In an upper tool for a press brake clamped between a support plate (7) of an upper tool holder body (5) attached to a lower portion of an upper table (3) and an upper tool clamp member (11), the upper tool (9) is formed with an inclined surface (9S) narrowed upward at an upper portion thereof and with an engage groove (9G) engaged with an engage projection (11K) of the upper tool clamp member (11) and formed under the inclined surface (9S). Therefore, the inclined surface (9S) is brought into contact with an inclined surface of the upper tool clamp member (11), when the upper tool is clamped between the upper tool holder body (5) and the upper tool clamp member (11), in such a way that clamping force can be-further increased when the upper tool is engaged with a die (63).

Abstract: In a bender (e.g., press brake), work (plate material) can be bent by a bending tool composed of a pair of punch and die. A position detector (17) mounted on a movable side of the bending tool generates a limit point pulse (ULi) whenever the tool reaches a limit point. A timer (29) measures a time interval between the two limit point pulses (ULi). A time compare discriminate section (31) compares the time interval measured by the time with a reference time interval (TR), and further discriminates the current bending as trial bending when the time interval is longer than the reference time but as an actual bending when shorter than the reference time. Further, an arithmetic section 33 calculates a sum total number of times of the bending and the sum total time period spent in the bendings, separately in both of the trial and actual bendings. The obtained bending data are displayed or recorded to obtain an accurate man-hour in the bending processing.

Abstract: In a punching tool having a punch body (23), a punch driver (33) integral with the punch body, a punch head (45) disposed over the punch driver and struck by a striker (59), a punch guide (15) for guiding the punch body, a stripper plate (17) disposed under the punch guide, and a stripping spring (51) interposed between the punch guide (15) and the punch driver (33), the punching tool further includes a first damping member (39) interposed between the punch guide (15) and the punch driver (33) so as to be elastically deformable within a predetermined deflection value. Owing to the presence of the first damping member (39), it is possible to reduce noise generated when the punch body (23) is returned upward by a strong urging force of the stripping spring (51) after work has been punched, thus reducing overall noise generated during punching processing.

Abstract: An upper tool holder apparatus (1) for removably supporting an upper tool (9) on an upper table (3) of a press brake includes: a holder body (5) removably attached to the upper table; an upper tool clamp (11) attached to the holder body, for pushing and fixing an upper portion of the upper tool to a support plate (7) provided at a lower portion of the holder body; a clamping force adjusting device (13) for adjusting a clamping force of the upper tool clamp; and a clamp releasing device (15) for releasing the upper tool clamped by the upper tool clamp. In particular, a wedge-shaped member (17) vertically movably provided at a lower portion of the upper tool clamp is formed with a stop portion (17K) engageable with and disengageable from an engage portion (9K) formed in the upper tool (9).

Abstract: A spot welder apparatus includes: a single welding power source (5); a welding current distributor (7) connected to the single welding power source; and a plurality of spot welders (1A, 1B, 1C) connected to the welding current distributor. Each of a plurality of the spot welders is activated alternately by welding current distributed by the welding current distributor. When two start signals are generated almost simultaneously, a first spot welder which generates the start signal earlier is activated, and a second spot welder which generates the start signal later is kept under pressurized condition. Immediately after the first spot welder is deactivated, the second spot welder is then activated. The spot welder apparatus is low in cost and small in installation space, without increasing the user' current capacity.

Abstract: A tool grinding machine which can grind the cutting edge of a punch without disassembling the punch body from the punch assembly and further can grind the cutting edge of the upper surface shoulder portion of the die. Further, the punch and die of various shapes can be ground easily by selecting an appropriate previously stored operation mode determined according to grinding conditions. The tool grinding machine is made up of a rotary table rotatably disposed on a slider supported on a base movable in the right and left direction; and a grinding tool disposed axially away from the rotary table and rotatable and movable in an axial direction of the rotary table, for a grinding workpiece fitted on the rotary table.

Abstract: In front of a bending machine is arranged a unit of a 5-axis control robot provided with a work hand at an end thereof, for loading work to the bending machine and unloading a bent work from the bending machine. A single-work taking-up device takes up only a single work from stacked works. Therefore, the work loading and unloading device is low in cost and requires a short program preparation and teaching (setup) time. The work loading and unloading device may be moved to any desired position and is provided with a work hand having a double-work take-up detecting device and an upper hand accessible to a bent work without interference with the punch.

Abstract: A stripper device for a punching tool comprises: a gas cylinder (5) filled with a gas (7) having a cylinder head (27) and a cylinder end (17) attached to a lower end of the cylinder head airtightly; and a piston (9) having a punch head (11) and a piston rod (15); an axial movement restricting member (13, 201) for restricting an axial movement of the piston in the gas cylinder filled with the gas; and a rotational movement restricting members (31; 205, 203) for restricting a rotational movement of the piston in the cylinder body. A stripping force of the stripper device can be obtained by a resilient force generated whenever the gas is compressed by the piston within the gas cylinder for each punching operation. The punch assembly enables plate material of various thicknesses to be punched out without generating stripping miss.

Abstract: In an upper tool, a stripper plate (35) is disposed movably up and down at a lower end portion (13a) of a punch guide (13) for housing a punch (27) also movably up and down, via a shock damping member (33). Further, the shock damping member (33) is formed into an annular body disposed so as to enclose an annular gap (X) formed between the lower end portion (13a) of the punch guide (13) and the upper surface (65) of the stripper plate (35). The upper tool can reduce noise sound generated during punching processing, and further prevent chips produced during punching processing from adhering onto the workpiece and the shock damping member, thus protecting the workpiece from being scratched by the chips and further improving the life time of the shock damping member.

Abstract: In a spot welding apparatus in which a column (7) is stood on a base (5) provided with a worktable (3) for supporting work (W); and a welding arm (15) having an electrode (13) at a free end portion thereof is pivotally supported up and down at a lower portion of a support cylinder (11) hung from a support beam (9) supported by the column (7) horizontally, the spot welding apparatus comprises an arm supporting section (47) for supporting support members (49, 55, 53, 57) for pivotally supporting the welding arm (15), so as to be movable up and down relative to the support cylinder (11) and further urged upward; and an arm pressing section (37) for pressing a free end portion of the welding arm (15) downward against an urging force of the arm supporting section.

Abstract: An upper tool for a press brake is removably attached on an upper tool holding device mounted on an upper table of the press brake, and includes a wedge portion having a contact surface brought into contact with a lower surface of a support plate provided on a holder body of the upper tool holding device. A slide surface is slidably brought into contact with any of front and rear surfaces of the support plate, and a clamp surface is brought into pressure contact with a pressing-down and fixing section of an upper-tool pressing-down and fixing member of the upper tool holding device. A work processing portion processes a workpiece in cooperation with a lower tool. Further, an upper tool holding device for a press brake, for removably mounting and supporting an upper tool on an upper table of the press brake, includes a holder body attached to the upper table.

Abstract: An upper tool (9) for a press brake, the upper tool being clamped to a supported body (5) mounted on an upper table (3) by a clamping force of a pressing-down and fixing member (11), includes: a shank to be clamped being formed with an inclined surface (9c) for gradually increasing the clamping force of the pressing-down and fixing member (11) to the upper tool (9) by relative movement of the upper tool (9) to the support body (5).