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EP-4282554-B1 - MAIN MEMBER FOR A WORKPIECE PROCESSING APPARATUS

EP4282554B1EP 4282554 B1EP4282554 B1EP 4282554B1EP-4282554-B1

Inventors

  • KIMURA, SHINYA
  • FURUSHIMA, TSUYOSHI

Dates

Publication Date
20260506
Application Date
20230522

Claims (10)

  1. A main member (11) configured to form a workpiece processing apparatus (10) together with a slider (61), the workpiece processing apparatus (10) being configured to use hydraulic pressure to process a workpiece (82) of an object (80), wherein: the main member (11) comprises a base member (20, 20A, 20F, 20S, 20T), a punch (64) and a piston (42); when the workpiece processing apparatus (10) is formed, the slider (61) is located above the base member (20, 20A, 20F, 20S, 20T) in an upper-lower direction and is movable between an upper position and a lower position in the upper-lower direction; the punch (64) is attachable to the slider (61); when the punch (64) is attached to the slider (61), the punch projects downward from the slider (61) and is moved in the upper-lower direction in accordance with a movement of the slider (61) in the upper-lower direction; the base member (20, 20A, 20F, 20S, 20T) is formed with a hydraulic chamber (50); the hydraulic chamber (50) is fillable with liquid (50L); the hydraulic chamber (50) has a workpiece processing chamber (51) and a hydraulic-pressure generation chamber (53); the workpiece processing chamber (51) and the hydraulic-pressure generation chamber (53) are coupled together and have openings (52, 54), respectively; the openings (52, 54) open outward from the base member (20, 20A, 20F, 20S, 20T) at positions different from each other; the piston (42) is partially received in the hydraulic-pressure generation chamber (53) so that the piston (42) is movable in the upper-lower direction and projects upward from the hydraulic-pressure generation chamber (53); the piston (42) receives a pressing force directed downward from the slider (61) in a course of movement of the slider (61) from the upper position to the lower position; when the slider (61) is moved from the upper position toward the lower position under a state where the hydraulic chamber (50) is filled with the liquid (50L) and the workpiece (82) is placed on the workpiece processing chamber (51), the punch (64) is moved downward and presses the workpiece (82) into the workpiece processing chamber (51), and the piston (42) is moved downward in accordance with the pressing force and increases hydraulic pressure of the liquid (50L); each of the workpiece processing chamber (51) and the hydraulic-pressure generation chamber (53) extends in the upper-lower direction and opens upward; the base member (20, 20A, 20F, 20S, 20T) is formed of an upper member (222), a lower member (224), a die (30) and a cylinder (40) combined together; the upper member (222) is placed on the lower member (224); each of the die (30) and the cylinder (40) is formed with a center hole; the workpiece processing chamber (51) extends through the center hole of the die (30); and the hydraulic-pressure generation chamber (53) extends through the center hole of the cylinder (40), characterized in that the die (30) and the cylinder (40) have upper end surfaces which are exposed upward from the upper member (222).
  2. A workpiece processing apparatus (10, 10A)comprising the main member (11) as recited in claim 1, wherein: the punch (64) is movable between an initial position which is apart from the opening (52) of the workpiece processing chamber (51) and a received position at which the punch (64) is partially received in the workpiece processing chamber (51) through the opening (52) of the workpiece processing chamber (51); when the punch (64) is moved from the initial position to the received position under a state where the opening (52) of the workpiece processing chamber (51) is covered by the workpiece (82), the punch (64) presses the workpiece (82) into the workpiece processing chamber (51); the piston (42) is partially received in the hydraulic-pressure generation chamber (53, 53A) through the opening (54) of the hydraulic-pressure generation chamber (53, 53A) so that the piston (42) is movable in the hydraulic-pressure generation chamber (53, 53A) and partially projects from the hydraulic-pressure generation chamber (53, 53A); and when the hydraulic chamber (50) is filled with the liquid (50L), the piston (42) receives a pressing force directed into the hydraulic-pressure generation chamber (53, 53A) via a resilient member (76) in a course of movement of the punch (64) from the initial position to the received position, and the piston (42) is moved in accordance with the pressing force and increases hydraulic pressure of the liquid (50L).
  3. The workpiece processing apparatus (10) as recited in claim 2, wherein: the workpiece processing apparatus (10) comprises the slider (61); and the punch projects downward from the slider (61) and is moved in the upper-lower direction in accordance with a movement of the slider (61) in the upper-lower direction.
  4. The workpiece processing apparatus (10) as recited in claim 3, wherein: the workpiece processing apparatus (10) comprises two or more workpiece processing sets (12); each of the workpiece processing sets (12) includes the hydraulic chamber (50), the piston (42) and the punch (64); all the punches project downward from the single slider (61); and the hydraulic pressure of at least one of the workpiece processing sets (12) is different from the hydraulic pressure of a remaining one of the workpiece processing sets (12) at a predetermined timing.
  5. The workpiece processing apparatus (10) as recited in claim 4, wherein at least one of the pistons (42) receives the pressing force from the slider (61) at a timing different from another timing at which a remaining one of the piston (42) receives the pressing force.
  6. The workpiece processing apparatus (10) as recited in claim 4, wherein: each of the workpiece processing sets (12) includes a spacer (72); all the spacers project downward from the single slider (61); each of the pistons (42) receives the pressing force from the spacer (72) in a course of movement of the slider (61) from the upper position to the lower position; when the slider (61) is located at the upper position, each of the spacers (72) is apart from the piston (42) by a predetermined distance in the upper-lower direction; and at least one of the predetermined distances is different from a remaining one of the predetermined distances.
  7. The workpiece processing apparatus (10) as recited in claim 6, wherein: each of the spacers (72) comprises a pressing portion (74) and the resilient member (76); each of the pressing portions (74) is configured to press the piston (42) downward; and each of the resilient members (76) has resiliency and supports the pressing portion (74) so that the pressing portion (74) is movable relative to the slider (61).
  8. The workpiece processing apparatus (10) as recited in claim 4, wherein: each of the pistons (42) has a body (44); each of the bodies (44) is partially received in the hydraulic-pressure generation chamber (53); and at least one of the bodies (44) has a cross-sectional area different from another cross-sectional area of a remaining one of the bodies (44) in a plane perpendicular to the upper-lower direction.
  9. The workpiece processing apparatus (10) as recited in one of claims 2 to 8, wherein: the main member (11) comprises a holder (65, 92) and a holder-support member (66); the holder (65, 92) is located outward of the punch (64) in a horizontal plane perpendicular to the upper-lower direction; the holder-support member (66) has resiliency and supports the holder (65, 92) so that the holder (65, 92) is movable relative to the slider (61); and when the slider (61) is moved downward under a state where the workpiece (82) is placed on the workpiece processing chamber (51), the holder (65, 92) is moved downward and presses the workpiece (82) against the base member (20, 20A, 20F, 20S, 20T).
  10. The workpiece processing apparatus (10) as recited in claim 9, wherein: the hydraulic chamber (50) has a branch channel (56); the branch channel branches off from the workpiece processing chamber (51) and has an opening (57) which opens outward from the base member (20, 20A, 20F, 20S, 20T); and when the holder (65, 92) presses the workpiece (82) against the base member (20, 20A, 20F, 20S, 20T), the opening (57) of the branch channel (56) is located below the holder (65, 92) in the upper-lower direction and is located outward of a peripheral edge (84) of the workpiece (82) in the horizontal plane.

Description

BACKGROUND OF THE INVENTION This invention relates to a workpiece processing apparatus configured to use hydraulic pressure to process a workpiece of an object. For example, US 4 419 876 A discloses a pressure control apparatus for hydromechanical drawing wherein the pressure chamber constitutes the drawing die. The control system has at least one two-diametered piston transmitter mounted in a hydraulic cylinder which on the side of the smaller diameter of the piston of the piston transmitter is connected to the space of the pressure chamber and on the other, larger diameter side of the piston transmitter is provided with a supply line for the pressure medium. The control system may include several hydraulic cylinders with two-diameter piston transmitters, the volume of the parallel hydraulic cylinders at the side of the smaller diameters of pistons of the piston transmitters is equal to, or greater than, the volume of the pressing in the pressure chamber. Further, the above mentioned type of workpiece processing apparatus is disclosed in JP H08-150426A (Patent Document 1). Referring to Fig. 15, Patent Document 1 discloses a workpiece processing apparatus 90 which is an existing typical workpiece processing apparatus configured to use hydraulic pressure to process a material (object) 98. The workpiece processing apparatus 90 comprises a die 91, a blank holder 92, a punch 93 and a hydraulic-pressure control device 95. The die 91 is formed with a hydraulic chamber 94. The hydraulic chamber 94 is filled with liquid such as oil. The hydraulic pressure of the liquid is controlled by the hydraulic -pressure control device 95 which includes a pump and a relief valve. The blank holder 92 can be vertically moved by a power device (not shown). The punch 93 can be vertically moved relative to the blank holder 92 by another power device (not shown). When the blank holder 92 is moved downward, the object 98 is sandwiched between the die 91 and the blank holder 92. Thereafter, when the punch 93 is moved downward, the object is drawn by using hydraulic pressure. The workpiece processing apparatus 90 disclosed in Patent Document 1 has a complex hydraulic-pressure control mechanism including the pump and the relief valve. However, there is a request for a workpiece processing apparatus having a simpler structure. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a new main member to be used in a workpiece processing apparatus which is configured to use hydraulic pressure to process a workpiece of an object and has a simpler structure. The above mentioned object is achieved by the main member as defined by claim 1 and the workpiece processing apparatus as defined by claim 2. The piston of the present invention is moved in accordance with the pressing force applied via the resilient member and increases the hydraulic pressure of the liquid. According to this structure, the hydraulic pressure can be prevented from being excessively increased by using the resiliency of the resilient member without providing a relief valve. In addition, since the liquid is kept in the hydraulic chamber because of a structure in which no relief valve is provided, the liquid does not need to be supplied from the outside. Therefore, there is no need to provide a complex hydraulic-pressure control mechanism including a pump and a relief valve. An aspect of the present invention provides a new workpiece processing apparatus which is configured to use hydraulic pressure to process a workpiece of an object and has a simpler structure. An appreciation of the objectives of the present invention and a more complete understanding of its structure may be had by studying the following description of the preferred embodiment and by referring to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a workpiece processing apparatus according to an embodiment of the present invention, wherein an object is placed on the workpiece processing apparatus, although illustrated punches and illustrated spacers are apart from a slider, the actual punches and the actual spacers are fixed to the slider, a part of the workpiece processing apparatus enclosed by chain dotted lines is enlarged and illustrated, and in the enlarged view, positions of hidden branch channels are illustrated with dashed line.Fig. 2 is a front view showing the workpiece processing apparatus of Fig.1, wherein positions of hidden punches are illustrated with dashed line.Fig. 3 is a rear view showing the workpiece processing apparatus of Fig.1, wherein positions of hidden hydraulic chambers are illustrated with dashed line.Fig. 4 is a plan view showing the workpiece processing apparatus of Fig.1, wherein the slider is not illustrated, and positions of openings of hidden workpiece processing chambers and positions of hidden pistons are illustrated with dashed line.Fig. 5 is a cross-sectional view showing the workpiece proce