JP2014094402A - Double-acting type extrusion press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-acting type extrusion press which holds a predetermined stop position without moving in longitudinal direction at a bearing part of a die during extrusion, and has holding means of a mandrel which suppresses fluctuation of a tip end position of the mandrel and obtains a tubular shaped product.SOLUTION: Provided on a main cross head is a position determination means for regulating a forward going position of a mandrel so that when a predetermined amount of pressure oil is supplied into a rod side chamber of a piercer cylinder and the mandrel stops during extrusion of the supplied amount and when the extrusion stem goes forward, the forward position of the mandrel coincides with an increased amount of the rod side chamber volume of the piercer cylinder.

Description

  In the present invention, a mandrel attached to the tip of a cylinder rod of a piercer cylinder provided inside a main ram is provided so as to be movable in the axial direction in a main cross head connected to the main ram, and is moved to the rod side of the piercer cylinder during extrusion. The present invention relates to a double-acting extrusion press that introduces pressurized oil to prevent the mandrel from moving forward and obtains a tubular extruded product.

2. Description of the Related Art Conventionally, an extrusion press that extrudes a tubular product by a double-acting extrusion method using, for example, copper, aluminum, or an alloy thereof, has a cylinder platen and an end platen arranged facing each other, and the cylinder platen has a main ram and an extrusion stem. The mandrel has a known configuration in which a die is provided on the end platen and a container that can be moved forward and backward by a container cylinder between the extrusion stem and the die.
The extrusion stem has a dummy block at the tip thereof, and is attached to a main ram incorporated in a main cylinder provided on the cylinder platen via a main cross head. A mandrel is arranged with the piercer cylinder rod so as to be able to accompany and advance and retract with the extrusion stem. A die is attached to the end platen so as to face the extrusion stem.

  A container is disposed between the extrusion stem and the die so as to freely advance and retract. Then, the billet is stored in the container. With respect to the billet stored in the container, the billet is pressed by the extrusion stem as the extrusion stem moves to the die side, and the upset is completed. After the upset, the mandrel advances and piercing is performed on the billet. The mandrel stops at a predetermined advance position of the die, and the extrusion stem advances, so that the billet is double-acted as a tubular product.

In a double-acting type extrusion press, when the product is pushed out by stopping the tip of the mandrel at a predetermined position on the die bearing, the position of the mandrel and the bearing is held so that they do not shift even if they are pulled by the product. Is done.
Patent Document 1 includes a piercer cylinder provided in a main cylinder, and a stopper forcibly connected to a mandrel off the extrusion press shaft core. The stopper acts on a hydraulic pilot valve, and is connected to a die. The supply of a certain amount of pressure oil medium from the hydraulic pump to the rod side chamber of the piercer cylinder is started so as to maintain a predetermined axial position (stop position) of the bearing portion. A double-action type extrusion press apparatus is disclosed in which the supply amount of the pressure oil medium is controlled to match the volume increase amount of the piercer cylinder rod side chamber when the mandrel stops and the main ram advances. Yes. (See Patent Document 1)

By the way, in the conventional double-acting type extrusion press, the mandrel is introduced into the rod side of the piercer cylinder by mechanically switching the hydraulic pilot valve via the stopper and the connecting rod to move the mandrel. Is held at a predetermined position on the bearing portion of the die, a movement delay is caused by a movement stroke corresponding to the land portion of the spool of the hydraulic pilot valve, and the tip end portion of the mandrel stops at a predetermined stop during extrusion molding. Move back and forth by a few millimeters relative to the position.
Furthermore, when the tip position of the mandrel is changed or the extrusion speed is changed, it is necessary to adjust the position of the stopper and the amount and pressure of the hydraulic medium supplied to the piercer cylinder each time.

Japanese Patent Publication No.49-26188

  The present invention has been made in order to solve the above-described problems, and maintains a predetermined stop position without moving back and forth at the bearing portion of the die during extrusion, and suppresses fluctuations in the tip position of the mandrel. An object of the present invention is to provide a double-acting extrusion press having a positioning means to obtain a tubular product.

  The double-action type extrusion press according to claim 1 of the present invention is provided with a main cross head which is provided so as to be axially slidable by a main cylinder and has an extrusion stem disposed at the tip thereof, and a mandrel which is connected to the extrusion stem and the main cross. A piercer cylinder provided in the main cylinder that is slidable in the head; a die provided on an end platen facing the extrusion stem; and a billet disposed between the extrusion stem and the die. In a double-action extrusion press having a container that is movable in the axial direction, a certain amount of pressurized oil is supplied to the rod side chamber of the piercer cylinder, and the mandrel is stationary during the extrusion, and An advance position of the mandrel that matches the amount of increase in the rod side chamber volume of the piercer cylinder when the extrusion stem moves forward. Positioning means for win, characterized in that provided in the main crosshead.

  The double-acting type extrusion press according to claim 2 of the present invention is the double-action type extrusion press according to claim 1, wherein the positioning means comprises a hydraulic cylinder as a main part, and when the extrusion stem moves in the extrusion direction, the hydraulic pressure The cylinder chamber pressure receiving area on the side from which the hydraulic oil is discharged from the cylinder and the rod side chamber pressure receiving area of the piercer cylinder are set to be substantially the same, and when the billet is pushed out by the pushing stem after piercing is completed, The cylinder chamber on the side from which hydraulic oil is discharged and the rod side chamber of the piercer cylinder are connected by a hydraulic line so as to communicate with each other.

  The double-action extrusion press according to claim 3 of the present invention is the cylinder according to claim 2, wherein the hydraulic oil is discharged from the hydraulic cylinder when the communicating extrusion stem moves in the extrusion direction. Pressure oil supply means for supplying pressure oil is provided in the hydraulic line between the chamber and the rod side chamber of the piercer cylinder.

  A certain amount of pressure oil is supplied to the rod side chamber of the piercer cylinder so that the supply amount matches the amount of increase in the volume of the rod side chamber of the piercer cylinder when the mandrel is stationary during extrusion and the extrusion stem moves forward. Since the main crosshead is provided with positioning means for regulating the mandrel advance position, the mandrel tip position during extrusion can be held at a predetermined fixed position, mandrel position can be easily held, and stop position accuracy can be improved. be able to.

When the extrusion stem moves in the extrusion direction, the cylinder chamber pressure receiving area on the side of the positioning means that discharges hydraulic oil from the hydraulic cylinder is substantially the same as the rod side chamber pressure receiving area of the piercer cylinder, and synchronizes with the extrusion stem during extrusion. Since the hydraulic oil discharged from the hydraulic cylinder chamber of the positioning means attached to the main crosshead is supplied to the rod side chamber of the piercer cylinder, the hydraulic oil supplied to the piercer cylinder even if the extrusion speed is changed during the extrusion operation There is no need to adjust the pressure and the amount of oil supplied each time, and operability can be improved.
When the extrusion stem moves in the extrusion direction, pressure oil is supplied to the cylinder chamber on the side of the hydraulic cylinder of the positioning means that discharges the hydraulic oil and the rod side chamber of the piercer cylinder, so the extrusion stem has advanced during extrusion. Since the mandrel position moves backward with respect to the extrusion stem by the stroke, the holding position accuracy of the mandrel with respect to the die position is improved. Further, during extrusion, the hydraulic pressure of the mandrel pull force acts on the discharge side of the cylinder chamber and acts similarly on the rod side of the piercer cylinder, so that the pushing force acting on the extrusion stem is not reduced.

It is sectional drawing which shows schematically the double acting type extrusion press of this invention. It is explanatory drawing which shows embodiment of this invention. It is explanatory drawing which shows the extrusion state which located the front-end | tip part of the mandrel in the bearing part of die | dye. It is explanatory drawing which shows other embodiment of this invention.

Hereinafter, a double-action extrusion press 10 according to the present invention will be described with reference to FIG. Fig. 1 (a) shows the state before the start of extrusion, Fig. 1 (b) shows the state in which the billet is stored in the container, Fig. 1 (c) shows the state in which the mandrel is inserted into the billet, and Fig. 1 (d) shows the state. Each shows the state after completion of extrusion.
As shown in FIG. 1A, an extrusion press 10 has an end platen 11 and a cylinder platen 12 facing each other, a die 21 is disposed on the end platen 11, a main cylinder 12a, a main ram 13, A main cross head 18 and an extrusion stem 14 are provided, and a container 20 is provided between the end platen 11 and the cylinder platen 12 so that the container 20 can be moved forward and backward by a container cylinder 24 disposed on the end platen 11.

The extrusion stem 14 is attached to a main ram 13 incorporated in a main cylinder 12 a provided on the cylinder platen 12 via a main cross head 18, and a mandrel 15 is located at the center of the extrusion stem 14. Along with the piercer cylinder rod 19, it is disposed so as to be able to accompany and advance and retract with the extrusion stem. The die 21 is provided on the end platen 11 so as to face the extrusion stem 14.
The billet 22 is supplied together with the dummy block 17 by a billet loader (not shown) between the die 21 and the container 20 moved to the cylinder platen 12 side. The dummy block 17 may be inserted into the container 20 by inserting only the billet 22 into the container 20 for smooth operation of the billet 22 and then moving the extrusion stem 14 backward to the center of the extrusion press by a dummy block supply device (not shown). .

Reference numeral 40 denotes positioning means for restricting the forward position of the mandrel 15 during extrusion. A hydraulic cylinder 41 as a main part thereof is attached to the main cross head 18, and a piston rod 42 is attached to the end platen 11 at its tip. The pressure receiving area of the cylinder chamber 32 on the side from which hydraulic oil is discharged from the hydraulic cylinder 41 and the piercer cylinder rod side chamber 31 are substantially the same when the extrusion stem 14 moves forward. Is set.
The cylinder chamber 32 and the piercer cylinder rod side chamber 31 on the side from which hydraulic oil is discharged from the hydraulic cylinder 41 are configured to communicate with each other by a hydraulic device to be described later, and the hydraulic oil discharged from the hydraulic cylinder 41 during extrusion is pierced. The stop position of the mandrel 15 is held by supplying the cylinder rod side chamber 31.

As shown in FIG. 1B, the billet 22 and the dummy block 17 are accommodated in a container 20 that is sandwiched between the die 21 and the extrusion stem 14 and moved forward. Upset is completed by pressing the billet 22 stored in the container 20 by moving the extrusion stem 14 toward the die 21.
Next, as shown in FIG. 1C, after the upset is completed, the mandrel 15 moves forward to pierce the billet 22, and the mandrel 15 stops at a predetermined forward position and the extrusion stem 14 moves forward. Thus, the billet 22 is extruded from the die 21 as a tubular extruded product 26 as shown in FIG.

  At this time, a certain amount of pressurized oil is supplied to the rod side chamber 31 of the piercer cylinder 23, and the volume of the head side chamber of the hydraulic cylinder 41 when the pusher stem 14 moves forward by the cylinder increase amount due to the stroke for making the mandrel position constant. Therefore, the stop position of the mandrel 15 is held during extrusion. The stop position of the mandrel 15 is set to a predetermined dimension S from the end face of the die 21.

Next, an embodiment of the double-action extrusion press 10 according to the present invention will be described in detail with reference to FIGS. 2 shows an embodiment of the present invention. Reference numeral 11 is an end platen, 12a is a main cylinder provided facing the end platen 11, 13 is a main ram slidably attached to the main cylinder 12a, and 18 is a main ram. The main cross head 18 is arranged so as to slide on a machine base (not shown).
The end platen 11 and the cylinder platen 12 can be held at a predetermined interval by a tie bar (not shown).

A piercer cylinder 23 is provided in the main ram 13, and a mandrel 15 is screwed to the tip of the piercer cylinder piston rod 19 via a mandrel holder (not shown). The mandrel 15 is slidably mounted in the extrusion stem 14 attached to the tip of the main cross head 18.
The end platen 11 is provided with a die 21 slidable in the horizontal direction with respect to the extrusion axis. A container 20 for storing the billet 22 is arranged so as to freely advance and retreat by a plurality of container cylinders 24 provided on the end platen 11. Reference numeral 17 denotes a dummy block disposed at the tip of the mandrel 15. The dummy block is supplied into the double-action extrusion press 10 together with a billet loader (not shown) together with the billet 22, or is combined with a dummy block supply device (not shown) separately from the billet 22. It is supplied into the dynamic extrusion press apparatus 10.

In FIG. 2, the code | symbol 31 shows the rod side chamber of the piercer cylinder 23, The pressure receiving area is set to A square centimeter. Reference numeral 32 indicates a cylinder chamber of the hydraulic cylinder 41 on the side from which the hydraulic oil is discharged when the extrusion stem 14 moves in the extrusion direction. Since the two hydraulic cylinders 41 are provided, the pressure receiving area of each cylinder is as follows. It is set to approximately one half of A (approximately 1/2 A square centimeter) so as to be substantially the same as the A square centimeter. In FIG. 2, since the hydraulic cylinder 41 is attached to the main cross head 18 and its piston rod 42 is attached to the end platen 11, the side chamber 32 from which hydraulic oil is discharged when the extrusion stem 14 moves in the extrusion direction is Head side.
Further, for example, in a configuration using four hydraulic cylinders 41, the pressure receiving area is set to approximately a quarter of A square centimeter (approximately 1/4 A square centimeter).

  With reference to FIG. 2, the structure of the hydraulic circuit 50 which concerns on the positioning means which regulates the advance position of the mandrel 15 of this invention is demonstrated. Reference numerals 51 and 52 are variable discharge hydraulic pumps that are driven by an electric motor (not shown). The variable discharge hydraulic pumps 51 and 52 are provided with a known pressure regulating valve or the like, and the pressure is regulated, and a necessary amount of pressure oil is supplied to the cylinders 41 and 23. Reference numeral 53 is an electromagnetic valve for operating the piercer cylinder 23, and reference numeral 57 is an electromagnetic valve for operating the hydraulic cylinder 41. Reference numerals 55 and 56 are operated when the cylinder chamber 32 of the hydraulic cylinder 41 and the rod side chamber 31 of the piercer cylinder 23 are communicated during extrusion. It is a solenoid valve. A chamber opposite to the cylinder chamber 32 (rod side chamber in FIG. 2) communicates with the tank line through the electromagnetic valve 58 during extrusion, and is configured to suck and discharge hydraulic oil according to the operation. Further, a check valve 59 is provided so that pressure does not act on the hydraulic cylinder 40 when the mandrel pull force suddenly increases.

The operation of the double acting extrusion press 10 configured as described above will be described. The billet 22 is placed on the billet loader together with the dummy block 17 and supplied to the extrusion center position. The supplied billet 22 advances the main ram 13 to bring the tip of the extrusion stem 14 into contact with the tip of the dummy block 17, and the container 20 is moved forward while being held between the die 21. The heavy billet 22 and the dummy block 17 are inserted and then upset is performed. When the push-out stem 14 is advanced, SOLb of the electromagnetic valve 57 is excited to discharge the hydraulic oil in the cylinder chamber 32 of the hydraulic cylinder 41 to the tank.
After upsetting, SOLb of the solenoid valve 53 is excited to introduce pressure oil into the piston head side chamber of the piercer cylinder 23, and the billet 22 is drilled (piercing) while the mandrel 15 is advanced, and the tip of the mandrel 15 is shown in FIG. The SOLb of the solenoid valve 53 is demagnetized so as to be stopped and held at a predetermined position of the bearing portion 21a of the die 21 shown.

  The predetermined stop position S shown in FIGS. 1 to 3 of the mandrel 15 (the relative position between the mandrel 15 and the die 21 is determined in advance before extrusion) is determined by the piston rod 19 of the piercer cylinder 23 or not shown. A scale sensor (not shown) may be attached in advance to the outer peripheral surface of the mandrel holder, and the relative position of the piston rod 19 and the piercer cylinder 23 may be determined, but the tip of the mandrel 15 is a predetermined part of the bearing 21 a of the die 21. However, the present invention is not limited to this as long as it is set at the stop position, and the relative position may be determined by another method.

  Next, the main ram 13 is advanced again to move the extrusion stem 14, and a tubular extruded product 26 having a desired uniform thickness is obtained from the die 21. During extrusion, the SOLb of the solenoid valves 55 and 56 is excited to connect the cylinder chamber 32 of the hydraulic cylinder 41 and the rod side chamber 31 of the piercer cylinder 23, and the SOLb of the solenoid valve 58 is excited to excite the rod side chamber of the hydraulic cylinder 41. Drain the hydraulic oil. As described above, since the pressure receiving areas of the cylinder chamber 32 of the hydraulic cylinder 41 and the rod side chamber 31 of the piercer cylinder 23 are set to substantially the same area, the piercer cylinder rod 19 is driven by the hydraulic oil discharged from the hydraulic cylinder 41. Relative movement is performed in synchronization with the forward speed of the extrusion stem 14. For this reason, the front end surface of the mandrel 15 at the predetermined stop position of the bearing portion 21a of the die 21 is always held at the predetermined stop position.

In the mandrel position holding during the extrusion to supply the oil discharged from the hydraulic cylinder 41 to the rod side chamber 31 of the piercer cylinder 23, the mandrel tip position is displaced due to the amount of leakage from the hydraulic cylinder or the like. In order to correct this deviation, a variable discharge hydraulic pump 52 is provided to supply pressure oil to the communicating hydraulic line. According to this configuration, even if internal leakage occurs in either one or both of the hydraulic cylinder 41 and the piercer cylinder 23, the supply of the predetermined flow rate to the pipeline is compensated, and the position holding accuracy of the mandrel 15 is changed. Never give.
At the end of extrusion, the SOLb of the electromagnetic valves 55 and 56 is demagnetized to block the communication of the pipeline.

At the end of extrusion, the head side of the main cylinder 12a is depressurized and pressure oil is introduced into the head side of the hydraulic cylinder 41 to retract the main ram 13, and the main cross head 18 and the extrusion stem 14 are retracted. Thereafter, the container 20 is further retracted, and the remaining push (discard) of the billet 22 is discharged, cut and removed from the container 20 and collected.
After cutting the discard, the container 20 is further moved backward to a position where the predetermined length of the extrusion stem 14 shown in FIG. 1A is stored, and the billet loader is placed between the tip end surface of the extrusion stem 14 and the die 21. To supply the billet 22 and the dummy block 17. The supplied dummy block 17 and billet 22 are sandwiched between the tip surface of the extrusion stem 14 that moves forward and the die 21 and loaded into the container 20 that moves forward. After the billet 22 and the dummy block 17 are loaded, the same operation is repeated.

  FIG. 4 shows another embodiment of the present invention. The difference from the configuration in FIG. 2 is that the billet 22 and the dummy block 17 are supplied to the gap between the container 20 and the extrusion stem 14 in a state where the container 20 is brought into contact with the die 21 and the extrusion stem 14 is in the retreat limit position. The billet 22 and the dummy block 17 are loaded into the container 20 by the forward movement of the extrusion stem 14, and the rest of the configuration is the same as that shown in FIG. Although not shown, in an indirect double-acting extrusion press having a structure in which a die stem having a die on the end surface on the side of the extrusion stem is provided on the end platen so as to face the extrusion stem instead of the die 21 shown in FIG. Can also be applied.

  In the above-described embodiment of the present invention, the mandrel is provided at the tip of the piercer cylinder rod via a mandrel holder (not shown). However, the present invention is not limited to this configuration. For example, the tip of the piercer cylinder rod A Pisa cross head with a mandrel attached to the part via a mandrel holder may be used so that this piercer cross head can be moved in the axial direction within the main cross head, and the mandrel can be rotated. A configuration may be used in which the pivoting means is provided on the piercer cross head.

As described above, the double-action extrusion press of the present invention supplies a certain amount of pressurized oil to the rod side chamber of the piercer cylinder, the mandrel is stationary during the extrusion, and the extrusion stem moves forward. Since the main cross head is provided with positioning means for restricting the advance position of the mandrel so as to substantially coincide with the amount of increase in the rod side chamber volume of the piercer cylinder at the time, the tip position of the mandrel is set to a predetermined die during extrusion. It can be held at a fixed position, the mandrel position holding can be easily controlled, and the position accuracy can be improved.
Further, even if the extrusion speed and the tip position of the mandrel are changed, there is no need to adjust the hydraulic oil pressure and the amount of oil supplied to the piercer cylinder each time, and the operability is improved. In addition, this invention is not limited to embodiment of the said invention, Of course, it can implement various deformation | transformation in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 10 Double acting type extrusion press 11 End platen 12 Cylinder platen 12a Main cylinder 13 Main ram 14 Extrusion stem 15 Mandrel 17 Dummy block 18 Main crosshead 19 Piercer cylinder piston rod 20 Container 21 Die 22 Billet 23 Piercer cylinder 24 Container cylinder 26 Tubular Extruded product 31 Piercer cylinder rod side chamber 32 Hydraulic oil discharge side chamber when hydraulic cylinder extruding stem advances 40 Mandrel positioning means 41 Hydraulic cylinder S Stop position of mandrel tip

Claims (3)

A main cross head which is provided so as to be freely movable in the axial direction by a main cylinder, and has an extrusion stem at the tip;
A piercer cylinder provided in the main cylinder that allows the mandrel to slide in the extrusion stem and the main crosshead;
A die provided on an end platen facing the extrusion stem;
In the double-action extrusion press that is disposed between the extrusion stem and the die and has a container that stores billets and is movable in the axial direction,
A certain amount of pressurized oil is supplied to the rod side chamber of the piercer cylinder, and the supply amount coincides with the amount of increase in the rod side chamber volume of the piercer cylinder when the mandrel is stationary and the extrusion stem moves forward during extrusion. A double-action extrusion press characterized in that positioning means for restricting the forward movement position of the mandrel is provided in the main cross head. The positioning means comprises a hydraulic cylinder as a main part. When the extrusion stem moves in the extrusion direction, the cylinder chamber pressure receiving area on the side from which hydraulic oil is discharged from the hydraulic cylinder and the rod side chamber pressure receiving area of the piercer cylinder are substantially equal. Set to the same,
When extruding the billet by the extrusion stem after completion of piercing, the cylinder chamber on the side from which hydraulic oil is discharged from the hydraulic cylinder and the rod side chamber of the piercer cylinder are connected by a hydraulic line to communicate with each other. The double-action extrusion press according to claim 1, wherein   When the communicating extrusion stem moves in the extrusion direction, pressure oil supply means for supplying pressure oil to the cylinder line on the side from which hydraulic oil is discharged from the hydraulic cylinder and the hydraulic line in the rod side chamber of the piercer cylinder The double-action extrusion press according to claim 2, wherein:

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