JP4643659B2 - Cylinder device for core pin drive - Google Patents

Description

  The present invention relates to a hydraulic cylinder device for driving a core pin that is detachably protruded from a cavity inner wall surface of a mold in die casting or injection molding.

In die casting, a large bending force is applied to the core pin that is projected and inserted into the inner wall surface of the cavity of the mold due to the solidification shrinkage of the molten metal filled in the cavity.
Also, when the mold is closed and the molten metal is injected into the cavity at a high speed and high pressure, a bending force acts on the core pin located in the molten metal flow.

And since the bending force acts for every product formation cycle, bending stress repeatedly occurs in the core pin, and metal fatigue occurs during many times of product formation.
In particular, the bending stress is intensively generated at the root of the portion of the core pin protruding from the inner wall surface of the cavity, and the core pin where metal fatigue has occurred is considered to be easily broken from the root portion.

In order to solve this problem, in Patent Documents 1 to 4 below, proposals have been made to devise the shape of the core pin so that the core pin can be appropriately bent when the molten metal is solidified and contracted.
Specifically, the core pin is a part that supports the product forming portion, and a small-diameter section or a circumferential groove is formed in the insertion portion that is fitted and inserted into the die perforation. When bending force acts on the pin, the core pin is bent flexibly to disperse the stress and prevent fatigue failure.

Japanese Utility Model Publication No. 63-189462 Japanese Patent Laid-Open No. 3-5085 No. 7-2132 JP 2002-126864 A JP 2005-329446 A

By the way, the direction of the bending force acting on the core pin at the time of molten metal injection and solidification shrinkage is determined by the mold configuration, such as the position and direction of the molten metal injection hole and the shape of the cavity. The bending stress in the same direction is generated every cycle.
Further, since the flow of the molten metal in the cavity when the molten metal is injected and filled is determined by the structure of the mold in the same manner as described above, the molten metal collides violently with the same area on the surface of the core pin and the area is damaged. As a result, defects such as deterioration of the quality of cast products occur.

To solve this problem, the degree of metal fatigue and surface deterioration can be reduced if the direction of bending stress acting on the core pin and the collision surface of the molten metal at the time of molten metal injection can be changed for each product formation cycle. it can.
The simplest method for this purpose is to rotate the core pin by a predetermined angle ( an integral multiple of 360 °) for each product forming cycle.
On the other hand, regarding the rotation of the core pin, the applicant of the present application has proposed a rod rotary cylinder device as shown in Japanese Patent No. 2841337 and Japanese Patent No. 3034827.
However, those proposals, when pulling out the core pin from the product obtained in the state where the molten metal is solidified or semi-solidified in the cavity, pull out after rotating the core pin, or pull out while rotating, The purpose is to reduce the pulling force, and the circumferential angle at the time of inserting the core pin into the cavity cannot be changed for each product forming cycle.
In addition, although the subject about the core pin used for die-casting was examined above, although the core pin used for injection molding is not as severe conditions as die-casting, the thermoplastic resin fluidized by heating is When cooling in the mold, a large bending force is applied.

Therefore, the present invention automatically sets the circumferential angle of the core pin to a predetermined angle (every product forming cycle) every time the core pin is inserted into and removed from the mold in die casting or injection molding. It is an object of the present invention to provide a core device for driving a core pin that can be changed in increments of ≠ 360 ° ( an integral multiple of 360 °).

A first invention is a hydraulic cylinder having a basic structure as a single rod type double acting cylinder, in which a core pin is connected to the tip end side of the rod, and the axial direction from the rear end side of the piston rod is described above. A cylinder part in which a female screw having a lead angle of 45 ° or more is formed in a hole formed deeper than the maximum stroke length of the piston rod, an intermediate shaft part pivotally supported by a head cover of the cylinder part, and the intermediate shaft part A front shaft portion formed with a male screw that is threaded in the whole stroke section with a female screw in a hole formed in the piston rod, and a rear portion continuous from the intermediate shaft portion to the rear. A rotation control shaft comprising a shaft portion, a shaft support mechanism for supporting the intermediate shaft portion of the rotation control shaft in the axial direction in the head cover of the cylinder portion, and supporting the shaft in the axial direction; A one-way clutch connected to the rear end of the rotation control shaft so that the rear shaft portion of the rotation control shaft can only rotate in one direction, and the rotation of the rotation control shaft by the movement of the piston rod by the maximum stroke length. For driving a core pin, wherein the maximum stroke length of the piston rod and the effective diameter and lead angle of each screw are set so that the rotation angle is an angle other than an integral multiple of 360 ° It relates to the cylinder device.

In the first aspect of the invention, when the piston rod is moved by supplying / discharging the hydraulic oil to / from each supply / discharge port of the cylinder portion which is a single rod type double acting cylinder, the rotation of the internal thread and the female screw in the hole of the piston rod Based on the screwed relationship with the male screw in the front shaft portion of the control shaft, rotational torques in opposite directions act on the piston rod and the rotation control shaft, respectively.
Therefore, when the direction of the rotational torque acting on the rotation control shaft and the one-way clutch rotation allowable direction are the same direction, the rotation control shaft rotates and the piston and rod move in a non-rotating state. When the direction of the rotational torque acting on the control shaft is opposite to the rotation allowable direction of the one-way clutch, the rotation of the rotation control shaft is blocked by the one-way clutch and the piston / rod moves in a rotating state.
Therefore, the following two types of operation modes can be obtained depending on the combination of the right-handed or left-handed screw thread and the one-way clutch rotation permission direction. (However, here, the rotation direction is not considered, and the operation order is divided, and there are four types when the rotation direction is considered.)
(A) In the process of retreating the piston rod from the forward limit position, the rotation control shaft rotates by a predetermined angle, the piston rod moves to the reverse limit position without rotating, and the piston rod moves from the reverse limit position. In the forward process, the rotation control shaft is not rotated, and the piston rod is rotated by a predetermined angle to move to the forward limit position.
(B) In the process of reversing the piston rod from the forward limit position, the rotation control shaft is not rotated, the piston rod is rotated by a predetermined angle and moved to the backward limit position, and the piston rod is moved from the backward limit position. In the forward process, the rotation control shaft rotates by a predetermined angle, and the piston rod moves to the forward limit position without rotating.
For this reason, when the piston rod is retracted and the core is pulled out of the mold, the piston rod is advanced and inserted into the mold again, so that the core and the rotation control shaft rotate by a predetermined angle. Thus, the core is automatically rotated by a predetermined angle for each cycle in which the core is pulled out and inserted.
The predetermined angle here is set to be an angle other than an integral multiple of 360 ° based on the maximum stroke length of the piston / rod and the effective diameter and lead angle of each screw related to the screwing relationship. The core pins are inserted at different circumferential angles for each cycle.

In the first invention, it is sufficient that the female screw formed in the hole of the piston rod is formed only in a predetermined section from the rear end side of the piston rod, so that the female screw can be easily processed. Become.
Further, if the front shaft portion of the rotation control shaft is a helical spline shaft and the female screw hole of the piston rod is formed as a helical spline groove that meshes with the helical spline shaft, the core is rotated when it is pulled out. In this case, a large rotational torque can be applied to the case [when the operation sequence (B) is adopted].

The second invention is a hydraulic cylinder having a basic structure as a single rod type double acting cylinder and having a core pin connected to the tip end side of the rod, and its piston rod (hereinafter referred to as “first piston. A basic structure as a single cylinder type double-acting cylinder and a first cylinder part in which a hole deeper than the maximum stroke length of the first piston rod is formed in the axial direction from the rear end side of the rod) A hydraulic cylinder connected to a head cover side of the first cylinder portion, and a rod of a piston rod (hereinafter referred to as “second piston rod”) is a hole of the first piston rod. to, capable of relative movement about the axial direction, with being fitted into through the mechanism for rotating integrally about the rotation direction, from the rear end side axial direction to said second of said second piston rod A two-stage connecting cylinder portion comprising a second cylinder portion in which a female screw having a lead angle of 45 ° or more is formed in a hole formed deeper than the maximum stroke length of the stone rod; and the second cylinder An intermediate shaft portion that is pivotally supported by the head cover of the portion, a male screw that continues forward from the intermediate shaft portion, and that engages with a female screw of a hole formed in the second piston rod in the entire stroke section. A rotation control shaft comprising a front shaft portion formed and a rear shaft portion continuous rearward from the intermediate shaft portion; and an intermediate shaft portion of the rotation control shaft in the axial direction in the head cover of the second cylinder portion. A one-way mechanism that is connected to the rear end of the head cover of the second cylinder portion and that allows the rear shaft portion of the rotation control shaft to rotate only in one direction. Hydraulic oil supply / discharge port for the front cylinder chamber of the first cylinder portion (hereinafter referred to as “first supply / discharge port”) and hydraulic oil supply / discharge for the front cylinder chamber of the second cylinder portion Between the port (hereinafter referred to as “second supply / discharge port”), the pressure on the first supply / discharge port side is equal to or higher than the set pressure at the stage where the first piston rod is retracted to the retreat limit. The valve is opened only in the state where the hydraulic fluid flows into the second supply / discharge port side from the first supply / discharge port side, and the second supply / discharge port side moves to the first supply / discharge port side. Is a first connection circuit that is connected via a sequence valve that flows hydraulic oil through a check valve, and a hydraulic oil supply / discharge port (hereinafter referred to as “third supply / discharge port”) to the rear cylinder chamber of the second cylinder portion. And a rear slit of the first cylinder part The pressure of the third supply / exhaust port causes the second piston / rod to protrude to the forward limit between the hydraulic oil supply / discharge port (hereinafter referred to as “fourth supply / discharge port”) to the compressor chamber. The valve opens only when the pressure exceeds the set pressure at the stage where the hydraulic oil flows from the third supply / exhaust port side to the fourth supply / exhaust port side, and And a second connection circuit connected via a check valve to the supply / discharge port side via a sequence valve, and the rotation by the movement of the second piston rod by the maximum stroke length The maximum stroke length of the second piston rod and the effective diameter and lead angle of each screw are set so that the rotation angle of the control shaft is an angle other than an integral multiple of 360 °. Through the third supply / discharge port A cylinder device for driving a core pin is characterized in that hydraulic oil is supplied to and discharged from the two-stage connecting cylinder.

In the second aspect of the invention, the first aspect rotates the core pin in the process of pulling out or inserting the core pin, while the core pin is pulled out or inserted in a non-rotating state. A child pin driving cylinder device is realized.
The basic configuration of the second cylinder portion, the rotation control shaft, the shaft support mechanism, and the one-way clutch in this invention is the same as that of the first invention. The rod of the second piston rod of the present invention is slid in the axial direction and engaged in the circumferential direction with respect to the hole of the first piston rod. And a core is connected to the tip end side of the rod of the first piston rod. Therefore, the mechanism functions so that the second piston rod and the first piston rod can move relative to each other in the axial direction and rotate integrally in the rotational direction.
The hydraulic oil is supplied / discharged to / from the two-stage connecting cylinder through the first supply / discharge port and the third supply / discharge port. The sequence control of each piston / rod is performed by the first connection circuit and the second connection circuit. Each sequence valve is executed.
First, in a state where the first and second piston rods are at the forward limit, the first supply / discharge port is connected to the hydraulic oil supply side to supply the hydraulic oil to the front cylinder chamber of the first cylinder portion. At the same time, the third supply / discharge port is used as a drain.
In that case, the sequence valve of the first connection circuit remains closed, the first piston rod moves backward in the first cylinder portion, and the hydraulic oil in the rear cylinder chamber of the first cylinder portion is supplied to the fourth supply / discharge port. It flows from the port to the third supply / discharge port side through the sequence valve of the second connection circuit, and is discharged to the drain as it is.
In the retraction process of the first piston rod, the hole of the first piston rod only allows the rod of the second piston rod to be inserted deeper by the function of the engagement mechanism.
When the first piston rod reaches the retreat limit in the first cylinder part, the pressure on the first supply / discharge port side becomes equal to or higher than the set pressure, the sequence valve of the first connection circuit is opened, and the hydraulic oil is 2 flows into the front cylinder chamber of the second cylinder from the supply / discharge port, and the second piston / rod is retracted.
When the second piston rod reaches the retreat limit in the second cylinder portion, the third supply / discharge port is switched to the hydraulic oil supply side, and the first supply / discharge port is switched to the drain side. The hydraulic oil is supplied to the rear cylinder chamber of the cylinder portion, and the second piston rod moves forward in the second cylinder portion. The hydraulic oil in the front cylinder chamber of the second cylinder portion is supplied from the second supply / discharge port. It flows to the first supply / discharge port side through the sequence valve of the connection circuit 1 and is discharged to the drain as it is.
By the way, as described above, the basic configuration of the second cylinder portion, the rotation control shaft, the shaft support mechanism, and the one-way clutch in the present invention is the same as that of the first invention. The operation mode in the process of the reciprocating motion of the rod is one of the two types [(A), (B)] described in the first invention.
Therefore, when the second piston rod reciprocates once, the second piston rod and the rotation control shaft automatically rotate by a predetermined angle (≠ an integral multiple of 360 °). Since one piston rod rotates integrally with the second piston rod, the first piston rod also rotates by the predetermined angle.
When the second piston / rod reaches the forward limit in the second cylinder, the pressure on the third supply / discharge port side becomes equal to or higher than the set pressure, the sequence valve of the second connection circuit is opened, and the hydraulic oil is opened. Flows from the third supply / exhaust port into the rear cylinder chamber of the first cylinder to advance the first piston rod. By the function of the above mechanism, the second piston is inserted into the hole of the first piston rod. Only the rod insertion amount of the rod becomes shallow, and the first piston rod does not rotate.
As a result, the first and second piston rods are in the original forward limit, but the first piston rod (and core pin) is at a predetermined angle (not an integral multiple of 360 °) as described above. The rotation control shaft is also rotated by the same angle.

  As in the first invention, in the second invention as well, the female screw formed in the hole of the second piston rod is a fixed section from the rear end side of the second piston rod. It is only necessary to form the front end of the rotation control shaft as a helical spline shaft, and the female screw hole of the second piston rod is formed as a helical spline groove that meshes with the helical spline shaft. You may make it keep.

  Further, a coupling mechanism between the rod of the second piston rod and the hole of the first piston rod in which the rod is fitted is formed on the outer peripheral surface of the rod of the second piston rod. An axially long key groove and an engagement / sliding mechanism with a key that is fixedly provided on the inner peripheral surface of the hole of the first piston rod and is fitted in the key groove to slide. If so, it can be realized with a simpler and easier processing.

Since the core device for driving the core pin of the present invention has the above configuration, the following effects can be obtained.
The cylinder device for driving the core pin according to the first and second aspects of the present invention is a cylinder device for inserting and extracting a core pin from a die casting mold or an injection mold by a drive system using a hydraulic cylinder. Each time it is inserted, the circumferential angle of the core pin is automatically changed by a predetermined angle (not an integer multiple of 360 °) to suppress the degree of metal fatigue or surface deterioration of the core pin, and its life Can be greatly extended.
The cylinder device for driving the core pin according to the first aspect of the invention can be configured with a relatively simple structure, and is formed on the female screw formed in the hole of the piston rod and the front shaft portion of the rotation control shaft. There is an advantage that the core pin can be rotated while being pulled out depending on the combination of the right screw or the left screw and the one-way clutch rotation permission direction.
The cylinder device for driving the core pin of the second invention can reciprocate the core pin by a required distance in a non-rotating state by selecting and designing the maximum stroke length of the first cylinder. Since the stroke length and the rotation angle of the core pin can be designed independently, high adaptability to the mold structure can be realized.

Hereinafter, each embodiment of the cylinder device for core pin drive of the present invention is described in detail based on a drawing.
<Embodiment 1>
This embodiment relates to the first invention, and its structure and operation state are shown in FIGS.
In FIG. 1A, reference numeral 11 denotes a cylinder portion, which has a basic structure as a single rod type double acting cylinder including a rod cover 12, a cylinder tube 13, a head cover 14, and a piston / rod 15.
Here, in the axial direction from the rear end side of the piston rod 15, enough even to interpolated the front shaft portion 20a of the rotary control axis 20 will be described later with its piston rod 15 has moved to the retreat limit deep 16 is formed, and a female screw (helical spline groove) 17 that is screwed into a male screw (helical spline screw) 20s of the front shaft portion 20a is formed in a predetermined section from the rear end side of the deep hole 16 Yes. However, the section where the female screw 17 is formed in this embodiment is formed by forming the female screw 17 in the hole of the annular thick plate and bonding and fixing it to the rear end face of the piston.
A core pin 19 is coaxially connected to the tip of the rod 15a of the piston rod 15 by a coupler 18.
The female screw 17 on the piston rod 15 side and the male screw 20s on the front shaft portion 20a are for converting linear driving force into rotational torque, and the lead angle of the screw is preferably 45 ° or more. The lead angle in this embodiment is set to 78 °.

Next, the head cover 14 of the cylinder portion 11 is not a simple end plate like a normal cylinder, but has a built-in shaft support mechanism.
The shaft support mechanism is a mechanism in which the intermediate shaft portion 20b of the rotation control shaft 20 is supported by a radial bearing 21, and the movement in the axial direction is restricted, and the front of the rotation control shaft 20 supported by the shaft is supported. The male screw 20s of the shaft portion 20a is screwed and fitted into the female screw 17 of the deep hole 16 of the piston rod 15, and the rear shaft portion 20c is projected to the one-way clutch 22 side.

The one-way clutch 22 is attached to the rear end surface of the head cover 14 of the cylinder portion 11 and holds the rear shaft portion 20c of the rotation control shaft 20.
In this embodiment, the one-way clutch 22 is of a package type, and a large number of inner rings and outer rings that are spaced apart in the radial direction and are concentrically disposed so as to be relatively rotatable are disposed between the inner ring and the outer ring. In this case, the outer ring is fixed, and the inner ring and the rear shaft portion 20c of the rotation control shaft 20 are engaged so as to rotate together.
When the rear shaft portion 20c is rotated counterclockwise when viewed from the front end side of the core pin 19 (hereinafter referred to as “CCW rotation”), the sprag cam surface meshes with the raceway surface of the inner and outer rings. By fitting, the rear shaft portion 20c is locked to prevent rotation, and in the reverse clockwise direction (hereinafter referred to as “CW rotation”), the rear shaft portion 20c is free with the cam surface of the sprag being detached. It can be rotated.

The core pin driving cylinder device of this embodiment having the above structure is attached to the mold 30 via the adapter plate 31 and supplies and discharges hydraulic oil to and from the supply and discharge ports 25 and 26 of the cylinder part 11. By switching with the 4-port 2-position switching valve 32, the core pin 19 is ejected / retracted.
First, FIG. 1A shows a state in which the piston rod 15 is positioned at the forward limit. In this state, the core pin 19 is inserted into the hole 33 of the mold 30 as shown in FIG. The molten metal 34 is poured into the cavity constituted by the mold 30 at high speed and high pressure, and when the molten metal 34 is cooled and solidified, the core pin 19 starts to be pulled out. However, at the injection stage of the molten metal 34 in a state where the mold 30 is closed, the switching valve 32 is set to be connected on the side opposite to the position in FIG.
1B and FIG. 1C schematically show the rotation angles of the core pin 19 and the rotation control shaft 20 when viewed from the front end side of the core pin 19, respectively. This is the same as in FIGS. 2 to 28 below.

When the core pin 19 is pulled out, the switching valve 32 is set as shown in FIG. 1 (A), and the supply / discharge port 25 is connected to the hydraulic oil supply source side, and the supply / discharge port 26 is connected to the drain side. Connect to.
Then, as shown in FIG. 2 (A), the hydraulic oil is supplied to the front cylinder chamber 11a of the cylinder portion 11 and the piston rod 15 is retracted, and the hydraulic oil in the rear cylinder chamber 11b is discharged from the supply / discharge port 26 to the drain. Returned.

By the way, in this embodiment, the male screw 20s of the front shaft portion 20a of the rotation control shaft 20 and the female screw 17 of the deep hole 16 of the piston rod 15 are screwed with a left screw, and the piston rod 15 is When retreating, rotational torque in the CW direction acts on the rotation control shaft 20, and conversely, rotational torque in the CCW direction acts on the piston rod 15 as a reaction.
However, on the piston / rod 15 side, friction between the core pin 19 and the molded product in the mold 30, friction between the piston / rod 15 itself and the inner peripheral surface of the cylinder tube 13, etc. While the rotation control shaft 20 acts as a counter-torque against the torque, the intermediate shaft portion 20b of the rotation control shaft 20 is supported by the radial bearing 21 in the head cover 14, and the one-way clutch 22 is a rear shaft portion 20c of the rotation control shaft 20. Is a function to rotate CW freely.
Accordingly, the rotation control shaft 20 rotates in the CW direction as shown in FIG. 2C, but the piston rod 15 moves backward without rotating, and the core pin 19 is also non-rotated as shown in FIG. Retreats in a rotating state and is pulled out of the molded product.

As the piston rod 15 moves backward, the piston rod 15 reaches the head end position as shown in FIG. 3A. At this stage, the core pin 19 is completely removed from the molded product. The molded product in which the hole is formed by pulling out the core pin 19 is taken out by opening the mold 30.
At this stage, as shown in FIGS. 3B and 3C, the core pin 19 does not rotate and remains as it is, and the rotation control shaft 20 is rotated by an angle θ. The apparatus is designed so that the rotation angle θ does not become an integral multiple of 360 °. That is, the rotation angle θ is determined by the maximum stroke length of the piston / rod 15 in the cylinder portion 11 and the effective diameter and lead angle (78 ° in this embodiment) related to the screwing relationship between the male screw 20s and the female screw 17. In this embodiment, these values are set so that the rotation angle θ is 50 °.

After the mold 30 is opened and the molded product is taken out, the mold 30 is closed again. At that stage, the switching valve 32 is switched as shown in FIG. On the drain side, the supply / discharge port 26 is connected to the hydraulic oil supply source side.
Therefore, the piston rod 15 moves forward from the backward limit by supplying the hydraulic oil to the rear cylinder chamber 11b of the cylinder portion 11 and returning the hydraulic oil from the front cylinder chamber 11a to the drain, and the core pin 19 is moved again to the mold. It protrudes from the 30 holes 33 into the cavity.

By the way, when the piston rod 15 moves forward, based on the left screw of the male screw 20s on the rotation control shaft 20 side and the female screw 17 on the piston rod 15 side, the reverse of the reverse movement process described above. Rotational torque in the CCW direction acts on the rotation control shaft 20, and rotational torque in the CW direction acts on the piston rod 15.
However, the one-way clutch 22 has a function to lock and prevent the rear shaft portion 20c of the rotation control shaft 20 from rotating in the CCW direction. Only the rod 15 rotates in the CW direction.
That is, as shown in FIGS. 4B and 4C, the core pin 19 connected to the rod 15a of the piston rod 15 is inserted into the cavity of the mold 30 while rotating in the CW direction. The rotation control shaft 20 is locked while maintaining the rotation angle (angle θ in the CW direction) in the backward movement process.

As shown in FIG. 5A, when the piston rod 15 moves to the forward limit, the piston rod 15 rotates from the state at the backward limit (the state of FIG. 3) by the angle θ in the CW direction. The core pin 19 connected to the rod 15a also rotates in the CW direction by an angle θ and is inserted into the hole 33 of the mold 30 as shown in FIG.
On the other hand, as shown in FIG. 5C, the rotation control shaft 20 does not change from the state in which the piston rod 15 is in the retreat limit (the state in FIG. 3), and from the initial state (the state in FIG. 1) to the CW direction. It remains rotated by an angle θ.

In addition, the preparation for the next cycle is completed in the state shown in FIG. 5, and the molten metal 34 is injected into the cavity of the mold 30 at a high speed and a high pressure as it is.
In this case, as is apparent from a comparison between FIG. 1 and FIG. 5, the piston rod 15 and the core pin 19 are in the same position as in FIG. Both the core pin 19 and the rotation control shaft 20 are rotated from the state of FIG. 1 by an angle θ in the CW direction.
Accordingly, the surface area of the core pin 19 where the flow of the molten metal 34 collides in the cavity is a surface area different from the previous injection of the molten metal 34 by the angle θ when viewed from the core pin 19.
Further, the bending force acting on the core pin 19 during the injection of the molten metal 34 and the direction of the bending force acting on the core pin 19 due to the solidification shrinkage action of the molten metal 34 cooled in the cavity after the injection are also determined. When viewed from the pin 19, it acts from a direction different from the previous direction by an angle θ in the circumferential direction.

What is important is that not only the piston rod 15 and the core pin 19 are rotated at the stage of completing the operation of one cycle, but also the rotation control shaft 20 is rotated in the same direction by the same angle. It is.
That is, it is possible to automatically rotate and insert the core pin 19 by an angle θ for each operation of one cycle, so that the surface of the core pin 19 in a certain region is intensively scratched or roughened. It is possible to effectively prevent occurrence of fatigue failure due to repeated stress.

<Embodiment 2>
The cylinder device for driving the core pin according to the second embodiment is also related to the first invention, and its structure and operation state are shown in FIGS.
However, the only difference from the device of the first embodiment is that the one-way clutch 35 has a function opposite to the rotation of the rear shaft portion 20c of the rotation control shaft 20, and the other elements and structures. Are exactly the same.
Therefore, the reference numerals indicating the elements and parts other than the one-way clutch 35 in each figure are the same as those in FIGS. 1 to 5 according to the first embodiment.
As described above, the one-way clutch 35 has a function opposite to that of the one-way clutch 22 of the first embodiment. Therefore, the CCW rotation of the rear shaft portion 20c of the rotation control shaft 20 is rotated freely, and the shaft is rotated for CW rotation. It has a function to lock and prevent rotation.

  In the second embodiment, not only the configuration of the apparatus of the first embodiment but also the screwing relationship between the male screw 20s of the front shaft portion 20a of the rotation control shaft 20 and the female screw 17 of the deep hole 16 of the piston rod 15 is employed. Regardless of the combination of the screw direction and the rotation direction in which the one-way clutch locks / frees the rear shaft portion 20c of the rotation control shaft 20, the core pin 19 is automatically angled by θ every cycle. Clarify that it can be rotated and inserted into the mold 30.

First, FIG. 6 shows a state in which the piston rod 15 is positioned at the forward limit. Except for the one-way clutch 35, FIG. 6 is the same as FIG.
In the state shown in FIG. 6, when hydraulic oil is supplied from the supply / discharge port 25 via the switching valve 32 and the supply / discharge port 26 is connected to the drain side, the piston rod 15 moves backward as shown in FIG. The core pin 19 connected to is pulled out from the molded product in the mold 30.

By the way, the male screw 20s of the front shaft portion 20a of the rotation control shaft 20 and the female screw 17 of the deep hole 16 of the piston rod 15 are screwed with a left screw, and in the retreating process of the piston rod 15 As in the case of the first embodiment (the state shown in FIG. 2), the rotational torque in the CW direction acts on the rotation control shaft 20, and the rotational torque in the CCW direction acts on the piston rod 15 on the contrary. .
Here, on the piston rod 15 side, friction between the core pin 19 and the molded product, friction between the piston rod 15 itself and the inner peripheral surface of the cylinder tube 13, etc. Acts as
On the other hand, with respect to the rotation control shaft 20, when the rear shaft portion 20c tries to perform CW rotation, the one-way clutch 35 locks it to prevent rotation.
Therefore, in this case, as shown in FIG. 7, the front shaft portion 20a of the rotation control shaft 20 does not rotate in the locked state, and the piston rod 15 is adjusted to the counter torque based on the screwing relationship. While rotating in the CCW direction, the core pin 19 connected to the rod 15a is also pulled out of the molded product in the mold 30 while rotating.

When the retraction accompanied by the rotation of the piston rod 15 proceeds, as in the case of the first embodiment (the state of FIG. 3), the piston rod 15 becomes the retreat limit position on the head cover 14 side as shown in FIG. At this stage, the core pin 19 is completely pulled out of the molded product, and the molded product in which the hole formed by the core pin 19 is formed is taken out by opening the mold 30.
However, at this stage, as shown in FIGS. 8B and 8C, the core pin 19 is rotated by an angle θ, but the rotation control shaft 20 is not rotated and remains unchanged. The operating state is opposite to that in the first embodiment.
Note that the rotation angle θ is set to 50 ° as an angle other than an integral multiple of 360 ° , as in the first embodiment.

  Next, when the mold 30 is opened, the molded product is taken out and the mold 30 is closed again, the switching valve 32 is switched as shown in FIG. 9A, and the hydraulic oil to the rear cylinder chamber 11b of the cylinder portion 11 is switched. And the return of hydraulic oil from the front cylinder chamber 11a to the drain advances the piston rod 15 from the retreat limit, and the core pin 19 is again protruded from the hole 33 of the mold 30 into the cavity.

By the way, when the piston rod 15 moves forward, the rotation control shaft 20 has a rotation control shaft 20 based on the screwed relationship between the male screw 20s on the rotation control shaft 20 side and the female screw 17 on the piston rod 15 side. A rotational torque in the CCW direction acts, and a rotational torque in the CW direction acts on the piston rod 15.
Here, friction with the inner peripheral surface of the cylinder tube 13 acts on the piston rod 15 side as a counter torque against the rotational torque.
On the other hand, with respect to the rotation control shaft 20, the one-way clutch 35 freely rotates the rear shaft portion 20c of the rotation control shaft 20 CCW.
Therefore, in this case, as shown in FIG. 9C, the rotation control shaft 20 rotates in the CCW direction, but the piston rod 15 advances without rotating, and as shown in FIG. The child pin 19 also moves forward in the hole 33 of the mold 30 in a non-rotating state.
That is, this operating state is also opposite to that in the first embodiment.

When the piston rod 15 moves to the forward limit as shown in FIG. 10A, the rotation control shaft 20 moves from the initial state (the state shown in FIGS. 5 to 8) to the CCW as shown in FIG. It is rotating in the direction by an angle θ.
On the other hand, the piston rod 15 does not change from the state in the retreat limit (the state shown in FIG. 3), and remains rotated in the CW direction by an angle θ. As shown in FIG. However, it is in a state of being inserted into the hole 33 of the mold 30 while maintaining the angle.

The preparation for the next cycle is completed at the stage shown in FIG. 10, and the molten metal 34 is injected into the cavity of the mold 30 at high speed and high pressure. However, the core pin 19 and the rotation control shaft 20 are both in the initial stage. It is rotated by an angle θ from the state (state of FIG. 6).
Therefore, as in the case of the first embodiment, the core pin 19 can be automatically rotated and inserted by an angle θ every operation of one cycle. Fatigue failure due to repeated stress on the surface can be prevented.

<Embodiment 3>
The core device for driving the core pin according to the third embodiment relates to the second invention, and its structure and operation state are shown in FIGS.
As shown in FIG. 11, the device according to the third embodiment connects two cylinder parts 41 and 51, which are single rod type double acting cylinders, to the front and rear, and connects the one-way clutch 22 to the rear end of the head cover of the cylinder part 51. It consists of a basic structure.

Here, the cylinder part 41 includes a rod cover 42, a cylinder tube 43, a piston rod 44, and a head cover corresponding to the rod cover part 52 of the cylinder part 51, and is connected to the rod 44a of the piston rod 44. A core pin 19 is connected coaxially by the vessel 18.
Moreover, deep hole 45 is formed in the axial direction from the rear end side of the piston rod 44.
The deep hole 45 has a depth sufficient to allow the rod 55a of the piston rod 55 to be inserted even when the piston rod 55 of the cylinder portion 51 is at the forward limit and the piston rod 44 has moved to the backward limit. In addition, a key 46 is fixed to the inner peripheral surface thereof so as to fit and slide in a key groove 55b formed in the rod 55a on the cylinder part 51 side.

By the way, regarding the cylinder part 51, the rotation control shaft 20 'and the one-way clutch 22, the basic structure is the same as that of the first embodiment except for the following differences (a), (b), (c). It is the same.
(a) The rod 55a of the piston rod 55 of the cylinder part 51 is not connected to the core pin 19 as in the case of the first embodiment, but is connected to the deep hole 45 of the piston rod 44 on the cylinder part 41 side. A key groove 55b is formed on the outer peripheral surface in a direction parallel to the shaft. As described above, the key 46 fixed to the deep hole 45 side of the piston rod 44 is fitted and slid with respect to the key groove 55b.
(b) The male screw 20s' of the front shaft portion 20a 'of the rotation control shaft 20' and the female screw 57 of the deep hole 56 of the piston rod 55 are screwed with a right screw, and the screwing relationship The lead angle at 45 is 45 °.
(c) The maximum stroke length of the piston / rod 55 of the cylinder portion 51 and the front shaft portion 20a ′ of the rotation control shaft 20 ′ are shorter than those in the first embodiment.

  As described above, the cylinder part 51 is substantially the same as the case of the apparatus of the first embodiment, so details of each element are omitted. However, 52 is a rod cover part, 53 is a cylinder tube, 54 is a head cover, 55 is a piston Rod, 56 is a deep hole, 57 is a female screw (helical spline groove; right screw), and 58 and 59 are supply / discharge ports.

  The front cylinder chamber of the cylinder portion 41 is connected to the front cylinder chamber of the cylinder portion 51 via a flow path formed in the cylinder tube 43 and a sequence valve 61 with a check valve, and the rear cylinder chamber of the cylinder portion 41 is The cylinder tube 43 and 53 are connected to the front cylinder chamber of the cylinder portion 51 through a flow path continuously formed in the cylinder tubes 43 and 53 and a sequence valve 62 with a check valve. Hereinafter, “sequence valve with check valve” is simply abbreviated as “sequence valve”.

Here, each of the sequence valves 61 and 62 and the port connection block has a circuit configuration as shown in FIG.
In the port connection block on the sequence valve 61 side, the port a connected to the switching valve 32 is always connected to the front cylinder chamber of the cylinder portion 41 through the flow path in the cylinder tube 43 from the port b, and the port a The connection from port to port c is activated only when the pressure at ports a and b (that is, the pressure in the front cylinder chamber of the cylinder portion 41) exceeds the set pilot pressure of the sequence valve 61. Oil flows, and conversely, the flow of hydraulic oil from port c to port a flows freely through the check valve.
In the port connection block on the sequence valve 62 side, the port a connected to the switching valve 32 is always connected to the rear cylinder chamber of the cylinder portion 51 through the flow path in the cylinder tube 53 from the port b. The connection from port to port c is activated only when the pressure at ports a and b (that is, the pressure in the rear cylinder chamber of the cylinder section 51) becomes higher than the set pilot pressure of the sequence valve 62. Oil flows, and conversely, the flow of hydraulic oil from port c to port a flows freely through the check valve.
The set pilot pressure of the sequence valve 61 is set to be larger than the maximum pressure generated in the retreating process of the piston rod 44 (in this case, the maximum pressure generated when the core pin 19 is pulled out). That is, when the piston rod 44 reaches the retreat limit, the hydraulic pump (not shown) increases the supply pressure of the hydraulic oil, but when the pressure exceeds the set pilot pressure, the sequence valve 61 opens. ing. In addition, the set pilot pressure of the sequence valve 62 is set to a pressure larger than the operating pressure in the forward process of the piston rod 55, and is a pressure obtained when the piston rod 55 reaches the forward limit. .

Based on the above configuration, the core pin driving cylinder device of this embodiment is attached to the mold 30 via the adapter plate 31, and the port a of each port block on the sequence valve 61 side and the sequence valve 62 side. By switching the supply and discharge of the hydraulic oil to and from the switching valve 32, the core pin 19 is ejected / retracted.
First, FIG. 11A shows a state in which the piston rods 44 and 55 of the cylinder portions 41 and 51 are positioned at the forward limit. As in the case of the first and second embodiments, in this state, FIG. ), The core pin 19 is inserted into the hole 33 of the mold 30 and the molten metal 34 is injected into the cavity formed by the mold 30 at high speed and high pressure. 19 withdrawals are made. However, at the injection stage of the molten metal 34 in a state where the mold 30 is closed, the switching valve 32 is set to be connected on the side opposite to the position in FIG.

  Here, when the switching valve 32 is set as shown in FIG. 11A, the hydraulic oil passes through the flow path in the port a → port b → cylinder tube 43 of the port connection block on the sequence valve 61 side and forward of the cylinder portion 41. On the other hand, the hydraulic oil in the rear cylinder chamber of the cylinder portion 41 is returned to the drain side through the flow path in the cylinder tubes 43 and 53 → port c of the port connection block on the sequence valve 62 side → port a. Therefore, the piston rod 44 moves backward as shown in FIG.

In this case, the core pin 19 is pulled out from the state of FIG. 11 (B) as shown in FIG. 12 (B).
Therefore, the pulling force becomes the load pressure on the piston rod 44, and the load pressure becomes the pilot pressure of the sequence valve 61. The set pilot pressure of the sequence valve 61 is generated when the core pin 19 is pulled out as described above. Since the pressure is set to be larger than the maximum pressure, the sequence valve 61 remains closed, and hydraulic fluid does not flow from port a to port c of the port connection block.
As a result, as shown in FIG. 12A, the piston rod 44 of the cylinder portion 41 moves backward, but the piston rod 55 of the cylinder portion 51 remains in the forward limit.

The rod 55a of the piston rod 55 is inserted into the deep hole 45 of the piston rod 44, but the key 46 of the piston rod 44 only slides in the key groove 55b of the piston rod 55. There is no engagement between the piston rods 44 and 55 in the process.
Further, since the piston rod 44 and the core pin 19 only retreat, and the piston rod 55 does not move, the core pin 19 and the rotation control shaft 20 'are shown in FIGS. 12B and 12C. Does not rotate.

Next, when the piston / rod 44 of the cylinder part 41 moves backward and reaches the backward limit as shown in FIG. 13A, the core pin 19 connected to the rod 44a is moved to FIG. 13B. As shown, the core pin 19 is completely pulled out from the molded product in the cavity, and the molded product in which the hole is formed by pulling out the core pin 19 is taken out by opening the mold 30, but the cylinder part The pressure in the front cylinder chamber 41 increases and exceeds the set pilot pressure of the sequence valve 61.
Then, the sequence valve 61 is changed from the closed state to the open state, and the hydraulic oil flows from the port a of the port connection block on the sequence valve 61 side through the port c into the front cylinder chamber of the cylinder portion 51.
On the other hand, since the port b and the port a in the port connection block on the sequence valve 62 side are always connected, the hydraulic oil in the rear cylinder chamber of the cylinder portion 51 freely returns to the drain.

  Therefore, immediately after the piston rod 44 of the cylinder part 41 reaches the retreat limit, the piston rod 55 of the cylinder part 51 retreats, but the male screw 20s ′ and the piston of the front shaft portion 20a ′ of the rotation control shaft 20 ′. The screw 55 is engaged with the female screw 57 of the deep hole 56 of the rod 55 with a right screw, and a rotational torque in the CCW direction acts on the rotation control shaft 20 ′ as shown in FIG. Conversely, rotational torque in the CW direction acts on the piston rod 55.

By the way, the rotation control shaft 20 ′ has its intermediate shaft portion 20b ′ supported by the radial bearing 21 in the head cover 54, but the one-way clutch 22 is used when the rear shaft portion 20c ′ of the rotation control shaft 20 ′ rotates CCW. Has a function to lock and prevent it.
On the other hand, regarding the rotation of the piston / rod 55 of the cylinder portion 51, the friction between the piston and the cylinder tube 53 and the circumferential engagement relationship between the key groove 55b of the rod 55a and the key 46 on the piston / rod 44 side are determined. The counter-torque due to the friction between the piston of the piston rod 44 and the cylinder tube 43 acting through them acts, but the rotation is not restricted like the rotation control shaft 20 ′ side.

Therefore, when the piston rod 55 is retracted as shown in FIG. 14A, the rotation control shaft 20 ′ is locked in a non-rotating state by the one-way clutch 22 as shown in FIG. Based on the screwing relationship with the rotation control shaft 20 'side, the vehicle moves backward while rotating CW.
Further, the rod 55a of the piston rod 55 and the deep hole 45 of the piston rod 44 can be moved relative to each other in the axial direction depending on the relationship between the key groove 55b and the key 46, and engage with each other in the rotation direction. -Since it is a sliding mechanism, only the CW rotation of the piston rod 55 is transmitted to the piston rod 44 as it is, and the piston rod 44 rotates CW in the retreat limit state as shown in FIG. .

When the retraction of the piston rod 55 proceeds, the piston rod 55 reaches the retreat limit position where the piston rod 55 reaches the head cover 54 side as shown in FIG. 15 (A). At that stage, FIGS. 15 (B) and 15 (C). As shown, the rotation control shaft 20 ′ does not rotate and remains the same, and the core pin 19 is rotated by an angle θ.
As in the case of the first embodiment, the rotation angle θ is equal to the maximum stroke length of the piston rod 55, the effective diameter and the lead angle related to the screwing relationship between the male screw 20s ′ and the female screw 57 (in this embodiment). 45 °) is designed so as not to be an integral multiple of 360 °. In this embodiment, θ = 50 °.
Since the lead angle 45 ° related to the screwing relationship in this embodiment is smaller than 78 ° in the first embodiment, a larger thrust of the piston rod 55 is required. The piston rod 55 in the form does not supply the pulling driving force of the core pin 19, and can be driven even if the lead angle is reduced. Further, the length of the cylinder part 51 is thereby reduced, and there is an advantage that the entire apparatus can be reduced in size.

As shown in FIG. 15A, in a state where the piston rod 44 and the piston rod 55 are in the retreat limit, a molded product in which a hole is formed by pulling out the core pin 19 is taken out by opening the mold 30.
When the mold 30 is closed again and the switching valve 32 is switched as shown in FIG. 16A, hydraulic fluid is supplied from the port a of the port connection block on the sequence valve 62 side, and the sequence valve Port a of the port connection block on the 61 side is connected to the drain.
In that case, the sequence valve 62 is in a closed state, the hydraulic oil flows from the port a through the port b to the rear cylinder chamber of the cylinder portion 51 to advance the piston rod 55, and the hydraulic oil in the front cylinder chamber is transferred to the sequence valve 61. From the port c of the side port connection block to the port a, the flow returns to the drain.

When the piston rod 55 advances, the rotation control shaft 20 is based on the screwed relationship between the male screw 20s ′ of the front shaft portion 20a ′ of the rotation control shaft 20 ′ and the female screw 57 of the deep hole 56 of the piston rod 55. Rotational torque in the CW direction acts on ', and conversely, rotational torque in the CCW direction acts on the piston rod 55.
By the way, the one-way clutch 22 has a function of freely rotating the rear shaft portion 20c ′ of the rotation control shaft 20 ′ by CW. Works.
Accordingly, as shown in each drawing of FIG. 16, as the piston rod 55 advances, the rotation control shaft 20 ′ rotates CW, and the piston rod 55 advances in a non-rotating state.
On the cylinder part 41 side, the sequence valve 62 remains closed, and hydraulic oil does not flow from port a to port c of the port connection block. The key 46 of the deep hole 45 of the rod 44 slides on the key groove 55b of the rod 55a of the piston rod 55 to accept the advance of the piston rod 55.

When the piston rod 55 reaches the forward limit of the cylinder portion 51, the state shown in each drawing of FIG.
At this stage, the rotation control shaft 20 ′ is rotated in the CW direction by an angle θ (= 50 °), and both the core pin 19 and the rotation control shaft 20 ′ are rotated by an angle θ from the initial state (FIG. 11). It was to be harassed.
Further, when the piston rod 55 reaches the forward limit, the pressure of the ports a and b of the port connection block on the sequence valve 62 side (that is, the pressure in the rear cylinder chamber of the cylinder portion 51) increases, and the sequence valve 62 When the set pilot pressure is exceeded, the sequence valve 62 switches from the closed state to the open state.

When the sequence valve 62 is in the open state, the hydraulic oil flows into the rear cylinder chamber of the cylinder portion 41, and the front cylinder chamber is connected to the drain when the switching valve 32 is switched. And as shown in (B), the piston rod 44 moves forward, and the core pin 19 protrudes into the cavity of the mold 30.
In this process, as shown in FIGS. 18B and 18C, the rotation control shaft 20 ′ and the core pin 19 do not rotate but rotate in the CW direction by an angle θ (= 50 °). keep.

When the piston rod 44 reaches the forward limit of the cylinder portion 41, the state shown in each drawing of FIG.
In this state, the piston rods 44 and 55 of the cylinder portions 41 and 51 return to the forward limit, and are the same as those in FIG. 11, but the rotation control shaft 20 ′ and the core pin 19 are respectively shown in FIG. It is rotated from the state 11 by an angle θ.
Therefore, also in the case of the third embodiment, it is possible to automatically rotate and insert the core pin 19 by the angle θ every operation of one cycle as in the case of the first embodiment. It is possible to prevent the surface degradation of the pin 19 and fatigue failure due to repeated stress on the surface of a certain region.

Further, according to the third embodiment, unlike the first and second embodiments, the core pin 19 is pulled out from the mold 30 side in a non-rotating state and rotated by an angle θ at the pulling position. This is effective when the pin 19 can be inserted into the mold 30 in the non-rotating state and insertion / removal of the core pin in the non-rotating state is required.
Furthermore, the stroke length of the piston rod 44 (medium) is independent of the screwing condition between the male screw 20s' of the front shaft portion 20a 'of the rotation control shaft 20' and the female screw 57 of the deep hole 56 of the piston rod 55. The stroke length of the child pin 19) can be freely selected.

<Embodiment 4>
The cylinder device for driving the core pin according to the fourth embodiment also relates to the second invention, and its structure and operation state are shown in FIGS.
However, the only difference from the apparatus of the third embodiment is that the one-way clutch 35 has a reverse function with respect to the rotation of the rear shaft portion 20c of the rotation control shaft 20, and the other elements and structures. Are exactly the same.
Accordingly, in each figure, reference numerals indicating elements and parts other than the one-way clutch 35 are the same as those in FIGS. 11 to 19.

Also, regarding the operating states, the states shown in FIGS. 20 to 28 correspond to FIGS. 11 to 19 in the third embodiment, respectively, and as will be apparent from a sequential comparison of the respective drawings, the third embodiment. The difference is that the rotation direction of the rotation control shaft 20 ′ and the core pin 19 is the CCW direction, and the rotation of the rotation control shaft 20 ′ precedes, and then the core pin 19 It is only the point that (piston rod 55, 44) is rotating.
This is based on the difference in function of the one-way clutch 35. That is, in the fourth embodiment, the one-way clutch 35 functions to lock the CW rotation and prevent the rotation of the rear shaft portion 20 ′, and to freely rotate the CCW rotation. This is the opposite of the one-way clutch 22.

  Of course, whether the rotation direction is the CW direction or the CCW direction, or which of the rotation control shaft 20 ′ and the core pin 19 rotates first is determined after the core pin 19 is pulled. Therefore, the core pin 19 is automatically rotated by an angle θ for each cycle of operation and inserted, and the effect of preventing the surface deterioration and fatigue failure of the core pin 19 is the same. This is similar to the case of the third embodiment.

  The present invention can be applied to a cylinder device used for inserting and removing a core pin from a die for die casting or injection molding.

(A) is sectional drawing which shows the operation state of the cylinder apparatus for core pin drive which concerns on Embodiment 1, (B) shows the state in which the core pin is inserted in the metal mold | die, and the rotation state of a core pin. FIG. 4C is a diagram showing a rotation state of the rotation control shaft, and relates to a stage where the piston rod (and the core pin) is at the forward limit. (A), (B), (C) is a figure which shows the state in the stage which the piston rod (and core pin) each retracted | retreated from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage in which the piston rod (and core pin) further retreated from the state of each figure of Drawing 2, and reached the retreat limit, respectively. (A), (B), (C) is a figure which respectively shows the state in the stage which the piston rod (and core pin) advanced from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage which the piston rod (and core pin) further advanced from the state of each figure of FIG. 4, respectively, and reached the advance limit. (A) is sectional drawing of the cylinder apparatus for core pin drive which concerns on Embodiment 2, (B) is a figure which shows the insertion state to the metal mold | die of a core pin, and the figure which shows the rotation state of a core pin, (C ) Is a diagram showing the rotation state of the rotation control shaft, and relates to the stage where the piston rod (and core pin) is in the forward limit. (A), (B), (C) is a figure which shows the state in the stage which the piston rod (and core pin) each retracted | retreated from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage in which the piston rod (and core pin) further retreated from the state of each figure of Drawing 7, and reached the retreat limit, respectively. (A), (B), (C) is a figure which respectively shows the state in the stage which the piston rod (and core pin) advanced from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage in which the piston rod (and core pin) further advanced from the state of each figure of FIG. 9, and reached the advance limit, respectively. (A) is sectional drawing of the cylinder apparatus for core pin drive which concerns on Embodiment 3, (B) is a figure which shows the insertion state to the metal mold | die of a core pin, and the figure which shows the rotation state of a core pin, (C ) Is a diagram showing a rotation state of the rotation control shaft, and relates to a stage where both the piston rod 44 (and the core pin) and the piston rod 55 are in the forward limit. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 44 (and core pin) each retracted | retreated from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage in which the piston rod 44 (and core pin) further retreated from the state of each figure of FIG. 12, and reached the retreat limit, respectively. . (A), (B), (C) is a figure which shows the state in the stage which the piston rod 55 retracted | retreated from the state of each figure of FIG. 13, respectively. (A), (B), and (C) are diagrams showing states at the stage where the piston rod 55 further moves backward from the state shown in FIG. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 55 advanced from the state of each figure of FIG. 15, respectively. (A), (B), (C) is a figure which shows the state which the piston rod 55 further advanced from the state of each figure of FIG. 16, respectively, and reached the advance limit. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 44 (and core pin) advanced from the state of each figure of FIG. 17, respectively. (A), (B), and (C) are views showing states at a stage where the piston rod 44 (and the core pin) further advance from the state of each drawing of FIG. 18 to reach the forward limit. . (A) is sectional drawing of the cylinder apparatus for core pin drive which concerns on Embodiment 4, (B) is a figure which shows the insertion state to the metal mold | die of a core pin, and the figure which shows the rotation state of a core pin, (C ) Is a diagram showing a rotation state of the rotation control shaft, and relates to a stage where both the piston rod 44 (and the core pin) and the piston rod 55 are in the forward limit. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 44 (and core pin) each retracted | retreated from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 44 (and core pin) further retracted from the state of each figure of FIG. 21, and reached the retreat limit, respectively. . (A), (B), (C) is a figure which shows the state in the stage which the piston rod 55 moved backward from the state of each figure of FIG. 22, respectively. (A), (B), and (C) are views showing states at the stage where the piston rod 55 further moves backward from the state shown in FIG. (A), (B), (C) is a figure which respectively shows the state in the stage which the piston rod 55 advanced from the state of each figure of FIG. (A), (B), (C) is a figure which shows the state which the piston rod 55 advanced further from the state of each figure of FIG. 25, and reached the advance limit, respectively. (A), (B), (C) is a figure which shows the state in the stage which the piston rod 44 (and core pin) advanced from the state of each figure of FIG. 26, respectively. (A), (B), (C) is a figure which shows the state in the stage in which the piston rod 44 (and core pin) further advanced from the state of each figure of FIG. 27, and reached the advance limit, respectively. .

Explanation of symbols

  11 ... Cylinder part, 12 ... Rod cover, 13 ... Cylinder tube, 14 ... Head cover, 15 ... Piston rod, 15a ... Rod, 16 ... Deep hole, 17 ... Female thread (helical spline groove), 18 ... Connector, 19 ... Core pin, 20,20 '... Rotation control shaft, 20a, 20a' ... Front shaft portion, 20b, 20b '... Intermediate shaft portion, 20c, 20c' ... Back shaft portion, 20s, 20s' ... Male thread (helical) Spline screw), 21 ... Radial bearing, 22 ... One-way clutch, 25 ... Supply / exhaust port, 26 ... Supply / exhaust port, 30 ... Mold, 31 ... Adapter plate, 32 ... 4-port 2-position switching valve, 33 ... Hole, 34 ... Molten metal, 35 ... One-way clutch, 41 ... Cylinder part, 42 ... Rod cover, 43 ... Cylinder tube, 44 ... Piston rod, 44a ... Rod, 45 ... Deep hole, 46 ... Key, 51 ... Cylinder part, 52 ... Rod Cover part, 53 ... Cylinder tube, 54 ... Head cover, 55 ... Piston rod, 55a Rod, 55b ... keyway, 56 ... deep hole, 57 ... female screw (helical spline grooves), 58 ... supply and discharge ports, 59 ... supply and discharge ports, 61 ... check valve with a sequence valve, 62 ... check valve with a sequence valve.

Claims (7)

Has the basic structure as a single rod type double acting cylinder, a hydraulic cylinder core pin is connected to the distal end side of the rod, the maximum stroke of the piston rod from the rear end side of the piston rod in the axial direction A cylinder part in which a female screw having a lead angle of 45 ° or more is formed in a hole formed deeper than the length;
An intermediate shaft portion that is pivotally supported by the head cover of the cylinder portion, and a male screw that continues forward from the intermediate shaft portion and that engages with a female screw in a hole formed in the piston rod in the entire stroke section. A rotation control shaft comprising a front shaft portion that is made and a rear shaft portion that is continuous rearward from the intermediate shaft portion;
A shaft support mechanism for supporting the intermediate shaft portion of the rotation control shaft in the head cover of the cylinder portion by restraining movement in the axial direction;
A one-way clutch coupled to a rear end of the head cover of the cylinder portion and configured to allow the rear shaft portion of the rotation control shaft to rotate only in one direction, and the movement by the maximum stroke length of the piston rod The maximum stroke length of the piston rod and the effective diameter and lead angle of each screw are set so that the rotation angle of the rotation control shaft is an angle other than an integral multiple of 360 °. Child pin drive cylinder device.   2. The core device for driving a core pin according to claim 1, wherein the female screw formed in the hole of the piston rod is formed only in a predetermined section from a rear end side of the piston rod.   The front shaft portion of the rotation control shaft is a helical spline shaft, and the female screw hole of the piston rod is formed as a helical spline groove that meshes with the helical spline shaft. Cylinder device for core pin drive. This is a hydraulic cylinder that has a basic structure as a single rod double acting cylinder, with a core pin connected to the tip of the rod, and after that piston rod (hereinafter referred to as "first piston rod") A first cylinder portion in which a hole deeper than a maximum stroke length of the first piston rod is formed in an axial direction from the end side, and a basic structure as a single rod double acting cylinder, The cylinder part of the hydraulic cylinder connected to the head cover side of the cylinder, the rod of the piston rod (hereinafter referred to as "second piston rod") is in the hole of the first piston rod, the axial direction be relatively moved, with being fitted into through the mechanism for rotating integrally about the rotation direction, the second piston rod from the rear end side of the second piston rod in the axial direction And 2-step connecting cylinder portion female thread is constituted by a second cylinder portion formed lead angle deeply formed hole than the maximum stroke length is 45 ° or more,
An intermediate shaft portion that is pivotally supported by the head cover of the second cylinder portion, and continues forward from the intermediate shaft portion, and is screwed in a full stroke section with respect to a female screw of a hole formed in the second piston rod. A rotation control shaft comprising a front shaft portion formed with a mating male screw, and a rear shaft portion continuous from the intermediate shaft portion to the rear;
A shaft support mechanism for supporting the rotation of the intermediate shaft portion of the rotation control shaft in the head cover of the second cylinder portion by restraining movement in the axial direction;
A one-way clutch connected to the rear end of the head cover of the second cylinder portion and configured to allow the rear shaft portion of the rotation control shaft to rotate only in one direction;
Hydraulic oil supply / discharge port (hereinafter referred to as “first supply / discharge port”) to the front cylinder chamber of the first cylinder portion and hydraulic oil supply / discharge port (hereinafter referred to as “first cylinder discharge port”) to the front cylinder chamber of the second cylinder portion. , The pressure on the first supply / discharge port side is equal to or higher than the set pressure at the stage where the first piston rod is retracted to the retreat limit. The valve is opened only in the state, and hydraulic oil flows from the first supply / exhaust port side to the second supply / exhaust port side, and the check valve is provided from the second supply / exhaust port side to the first supply / exhaust port side. A first connection circuit connected via a sequence valve for flowing hydraulic oil through
Hydraulic oil supply / discharge port (hereinafter referred to as “third supply / discharge port”) to the rear cylinder chamber of the second cylinder portion and hydraulic oil supply / discharge port (hereinafter referred to as “third cylinder supply / discharge port”). , "The fourth supply / discharge port"), the pressure of the third supply / discharge port is equal to or higher than the set pressure at the stage where the second piston rod is protruded to the forward limit. The valve is opened only to flow hydraulic oil from the third supply / discharge port side to the fourth supply / discharge port side, and a check valve is connected from the fourth supply / discharge port side to the third supply / discharge port side. And a second connection circuit connected via a sequence valve for flowing hydraulic oil through, a rotation angle of the rotation control shaft by movement of the second piston rod for the maximum stroke length is an integral multiple of 360 ° The second piss so that it has an angle other than The maximum stroke length of the rod and the effective diameter and lead angle of each screw are set, and the hydraulic oil to the two-stage connecting cylinder through the first supply / discharge port and the third supply / discharge port The core device for driving the core pin is characterized in that supply and discharge of the core pin is performed.   5. The core pin driving cylinder according to claim 4, wherein the female screw formed in the hole of the second piston rod is formed only in a predetermined section from a rear end side of the second piston rod. apparatus.   The front shaft portion of the rotation control shaft is a helical spline shaft, and the female screw hole of the second piston rod is formed as a helical spline groove that meshes with the helical spline shaft. A cylinder device for driving a core pin as described in 1.   The mechanism between the rod of the second piston rod and the hole of the first piston rod in which it is fitted is an axial direction formed on the outer peripheral surface of the rod of the second piston rod. An engagement / sliding mechanism for a long key groove and a key fixed to the inner peripheral surface of the hole of the first piston rod and sliding in the key groove. A cylinder device for driving a core pin according to claim 4, claim 5 or claim 6.

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