JPH0233476B2 - TAIBAANATSUTOBUNKATSUSOCHI - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a method for fixing a tie bar to a fixed plate when inserting or removing the tie bar for mold replacement in an injection molding device such as a die casting machine or an injection molding machine. This relates to a tie bar nut splitting device that loosens and opens a tie bar nut, and closes and tightens a tie bar nut.

[Conventional technology]

In die casting machines, injection molding machines, etc.
When replacing the mold, if the dimensions of the mold are larger than the spacing between the tie bars, loosen and remove the tie bar nuts that secure the tie bars, pull out the tie bars from the fixed plate toward the movable plate, and then replace the mold. The work involved pushing the tie bar and tightening the tie bar nut. In this case, loosening and removing the heavy tie bar nuts, or installing and tightening them requires a lot of effort and is inefficient. Various tie bar nut splitting devices have been proposed in which the tie bar is loosened and opened while supported on the side, the tie bar is removed and inserted, and the tie bar nut is closed and tightened.

For example, what is disclosed in Japanese Utility Model Publication No. 59-32449 is to rotatably support a rotary plate whose movement in the axial direction is restricted in the tie bar insertion hole of a fixed plate, and insert the tie bar into the inner hole. The piston rod of the cylinder is pivotally connected to the other end of the half-split tie bar nut, one end of which is pivotally connected to this rotary plate, and by moving the piston rod forward and backward, the tie bar nut can be loosened or tightened, and both half-split tie bar nuts can be loosened or tightened. A link is provided between the free ends of the pieces, and the half tie bar nut is opened and closed via this link in conjunction with the forward and backward movement of the piston rod.

Further, for example, the device disclosed in Japanese Utility Model Publication No. 54-19294 is the same as the above device in that it is provided with a rotary plate and a cylinder for rotating a half-split tie bar nut, but in addition to this, another cylinder is provided. is supported by a rotary plate, and the half-split tie bar nut is opened and closed via a toggle mechanism as the piston rod advances and retreats.

[Problem that the invention seeks to solve]

However, in conventional tie bar nut splitting devices like this, the tie bar nut is loosened by turning it while it is tightly tightened with a cylinder and surface pressure is applied, so the pressure surface of the tie bar nut and rotary plate is likely to wear and durability cannot be expected. In addition, if there is axial play that exceeds the rotation angle due to machining errors or wear, the tie bar nut will not be tightened sufficiently even if the cylinder is operated as much as possible. There were problems such as the need for precision and the need for early parts replacement. In addition, since the tie bar nut is supported by a fixed plate via a rotating plate, it is difficult for the center of the tie bar nut and the tie bar to come out, and seizing is likely to occur when the tie bar nut is rotated every time the tie bar is inserted and removed. There was a problem. Furthermore, since the tie bar flange and the tie bar nut are tightened so as to strongly clamp the fixed plate, stress is concentrated on the flange, and the flange surface may dig into the tie bar hole, making it difficult to remove the tie bar.

[Means for solving problems]

In order to solve such problems, in the present invention, a half-shaped tie bar nut which can be opened and closed and is pivoted on the fixed plate side is screwed onto the threaded part of the tie bar protruding from the hole in the fixed plate, and a half tie bar nut is screwed onto the threaded part of the tie bar protruding from the hole in the fixed plate. A pressing pin whose tip end surface is in contact with the end surface of the tie bar is screwed into the screw hole of the screw receiving plate which is provided oppositely so that it can move forward and backward, and the screw tightening lever is fixedly supported by this pressing pin, and the screw tightening lever is oscillated. The movable end is engaged with a piston rod operating end of a fluid pressure cylinder supported on the fixed platen side, and the free ends of each half piece of the tie bar nut are pivoted to each other. 4 by connecting the first link and second link.
A joint link is formed so that the working end of the piston rod and the first link are engaged with each other during the movement of the piston rod.

[Effect]

For example, when the piston rod of the fluid pressure cylinder is moved backward when replacing a mold, etc., the screw tightening lever swings and the press pin rotates in the direction of loosening the screw, and its tip separates from the protruding end surface of the tie bar. The threaded portion is released from the threading surface pressure of the tie bar nut, allowing the tie bar nut to open and close. As the piston rod continues to move backward, it engages with the first link of the four-bar link, so both halves of the tie bar nut open via the four-bar link and are unthreaded from the threaded portion of the tie bar. After removing the tie bar and replacing the mold, the tie bar is inserted and the piston rod of the fluid pressure cylinder is advanced.The tie bar nut closes via the four-bar link and is screwed into the threaded part of the tie bar.
By further advancing the piston rod,
Only the screw tightening lever rotates and the pressing pin rotates in the screw tightening direction, so the tip end of the pressing pin is strongly pressed against the protruding end surface of the tie bar, and the tie bar is slightly pressed, causing a threaded part between it and the tie bar nut. The threading surface pressure is applied.

〔Example〕

1 to 5 show an example in which the tie bar nut splitting device according to the present invention is implemented in a die casting machine, FIG. 1 is a side view thereof, and FIG. 2 is the same as that in FIG. 1.
AA sectional view, FIG. 3 is a sectional view showing the opened tie bar nut corresponding to FIG. 2, FIG. 4 is a schematic side view of a die casting machine implementing the present invention,
FIG. 5 is a schematic side view showing the same state with the tie bar removed. In the figure, a fixed platen 3 and another movably adjustable fixed platen 4 are erected on a machine base 2 of a die-casting machine 1, and the four corners of both fixed plates 3 and 4 are connected by tie bars 5. has been done. 3 or 2 of the 4 tie bars 5
The book is fixed on the fixed platen 3 side with nuts 6,
A tie bar nut dividing device 10, which will be described later, is provided on the fixed platen 3 side of the remaining one or two tie bars 5. Reference numeral 7 denotes a movable plate supported by a tie bar 5 so as to be able to move forward and backward relative to the fixed plate 3, and between the movable plate 7 and the fixed plate 4, there is a mold clamping device including a toggle mechanism (not shown). is provided, and by moving the movable platen 7 forward and backward with this mold clamping device, the fixed mold 8 and the movable mold 9 attached to the fixed platen 3 and the movable platen 7, respectively, are clamped and opened. It is configured as follows.

The tie bar 5 to which the tie bar nut splitting device 10 is attached is inserted into the tie bar hole 3a of the fixed plate 3 from the movable plate 7 side so as to be freely inserted and removable, and protrudes outward. A fixed plate of a tie bar nut splitting device 10 through which a tie bar 5 passes through the center is fixed by four stays 12. Reference numeral 13 denotes a substantially rectangular screw receiving plate which is connected to the fixing plate 11 by two flat stays 14 and the stay 12, and its plane has a reference numeral in FIG. They face each other with an interval indicated by S, and a left-handed threaded hole 13a is provided in the center thereof, substantially coaxial with the tie bar 5. Note that the protruding end of the tie bar 5 is provided with a plurality of chamfered parts 5b, of which the upper chamfered part 5
A stopper 15 protruding from the screw receiving plate 13 is engaged with the stopper 15 and abuts against the stepped surface of the chamfered portion 5b, so that the gap S can be maintained accurately. 1
Reference numeral 6 denotes a pressing pin with a square head 16b whose screw portion 16a is screwed into the screw hole 13a so as to be freely retractable. In the blank portion, a screw tightening lever 17 is interposed between the screw receiving plate 13 and the protruding end surface 5a of the tie bar 5 and is fixed with a key 18.

On the other hand, a pin 19 that connects the screw receiving plate 13 and the fixing plate 11 at the same height as the tie bar 5 has a tie bar nut 22 that is divided into an upper divided piece 20 and a lower divided piece 21 in the shape of a semicircular arc. One end is rotatably supported so that it can be opened and closed, and by closing both the divided pieces 20 and 21 as shown in FIG. They are configured to be screwed together. On the other hand, a trunnion-type hydraulic cylinder 24 as a fluid pressure cylinder is swingably supported on a connecting plate 23 that connects the upper ends of the screw receiving plate 13 and the fixed plate 11 via a bracket 25. An inverted U-shaped metal fitting 27 is integrally formed at the downwardly directed working end of the piston rod 26. A pin 28 is provided at the lower end of the metal fitting 7, and this pin 28
is engaged with a long hole 17a provided at the free end of the screw tightening lever 17. As a result, when the piston rod 26 rises from the state shown in FIG. 2 to the state shown in FIG.
rotates clockwise in the figure, the pressing pin 16 rotates in the direction of loosening the left screw, and when the piston rod 26 descends from the state shown in FIG. 3 to the state shown in FIG. 2, the screw tightening lever 17 rotates counterclockwise in the figure to rotate the pressing pin 16 in the screw tightening direction. Then, when the pressing pin 16 rotates in the direction of loosening the left-hand screw, the pressing pin 16
When the tie bar nut 22 and the tie bar 5 are separated from each other, the pressure on the screwing surface between the tie bar nut 22 and the tie bar 5 is released, and the tie bar nut 22 can be opened and closed. Also, when the pressing pin 16 rotates in the direction of tightening the left-hand thread, the pressing pin 16 moves against the tie bar 5. The tie bar nut 22 and the tie bar 5 are in pressure contact with the end surface 5a of the tie bar nut 22 and the tie bar 5, and are configured to be firmly fixed to each other by applying a threading surface pressure. 17b
is a spacer.

The one indicated by the reference numeral 29 in the figure is formed in an inverted L shape and has one end attached to the upper divided piece 20 of the tie bar nut 22.
The first link is pivotally connected to the free end of
The member 29c is fixed in a U-shape when viewed from the side, and on both sides of the vertically elongated thin wall portion 29a at the center in the axial direction of the tie bar 5, there are inverted U-shapes that are the working ends of the piston rods 26. metal fittings 2
7 engages with the thin wall portion 29a so as to sandwich it therebetween. A groove 29b is provided in the thin wall portion 29a as an engaging portion with the pin 28, and the groove 29b serves as an engagement portion with the pin 28.
The pin 28 and the groove 29b are configured to engage with each other during the movement of the piston rod 26 such that the pin 7 is rotated in the direction of loosening the left screw of the pressing pin 16. When the piston rod 26 further rises after the pin 28 and the groove 29b are engaged, the first ring 2
9 rotates together with the piston rod 26. Furthermore, the lower end of the first link 29 and the free end of the lower divided piece 21 of the tie bar nut 22 are connected to an inverted T-shaped second
The pins 19, 30, 3 are connected by a link 33, and the first link 29, the second link 33, and the upper divided piece 20 and lower divided piece 21 of the tie bar nut 22.
A four-node link with four nodes 1 and 32 is formed. When the piston rod 26 rises from the position shown in FIG. 2, the upper divided piece 20 of the tie bar nut 22 rotates as described above, and at the same time, the lower divided piece 21 also rotates due to the action of the four-bar link. In this case, as shown in FIG. 3, when the upper divided piece 20 contacts the stay 12 and finishes opening, the first link 29 rotates around the pin 30, and the lower divided piece 21 opens with the stay 12. Open until it touches 12.

The operation of the tie bar nut splitting device configured as above will be explained. During normal times, the piston rod 2 of the hydraulic cylinder 24 is
6 is lowered and the metal fitting 27 and screw tightening lever 17
The pressing pin 16 has come out inward from the screw hole 13a through the screw hole 13a, and its tip face strongly presses the end face of the tie bar 5, so the tie bar nut 22 and the tie bar 5 are fixed by the surface pressure of the threaded part. has been done.

As shown in FIG. 4, when replacing the molds 8 and 9 whose dimensions are larger than the spacing between the tie bars 5, when the piston rod 26 of the hydraulic cylinder 24 is raised from the state shown in FIG. The engaged screw tightening lever 17 rotates clockwise in FIG.
Since the part 3a is loosened, the surface pressure acting on the threaded part between the tie bar nut 22 and the tie bar 5 is released.
The tie bar nut 22 can be opened and closed. When the piston rod 26 continues to rise, the pin 28 engages with the groove 29b of the first link 29, and after this, the first link 29 and the upper divided piece 20 of the tie bar nut 22 rotate together around the pin 19. Then, the upper divided piece 20 opens until it comes into contact with the stay 12. When the piston rod 26 is further raised, the first link 29 rotates clockwise about the pin 30, so that the lower divided piece 2
1 rotates and opens until it abuts on the stay 12. In this case, due to the resistance of the pins 30, 31, 32, etc., both the divided pieces 20, 21 may open at the same time, or the lower divided piece 21 may open first, but the result is shown in Fig. 3. The two divided pieces 21 are opened until they come into contact with the stay 12. By opening the tie bar nut 22 in this way, the tie bar 5 can move forward and backward, so the tie bar 4 is pulled out from the tie bar hole 3a and moved toward the movable platen 7, as shown in FIG. Exchange.

After replacement, insert the tie bar 5 into the tie bar hole 3a and let it protrude until it contacts the stopper 15, and then lower the piston rod 26 of the hydraulic cylinder 24 from the state shown in FIG. At the same time as the metal fitting 27 begins to rotate counterclockwise, the first
Since the end face of the link 29 is pushed, the first link 29 rotates counterclockwise in the figure around the pin 30 and descends due to the push-down action of the metal fitting 27 and its own weight.
At this time, due to the rotation and descent of the first link 29, the second link 33 and the lower divided piece 21, which had been bent in an inverted shape, are rotated into an inverted shape, so that the metal fittings 27 descends along the end surface 29c, the upper and lower divided pieces 20, 21 are closed. End face 27a of metal fitting 27 and end face 29c of first link 29
The upper and lower divided pieces 20, 21 are completely closed in a state where they are in close contact with each other, and the tie bar nut 22 and the tie bar 5 are screwed together. After this, the pin 28 separates from the bottom of the groove 29b and the piston rod 26 continues to descend further, so only the screw tightening lever 17 continues to rotate, and the pressing pin 16 slips inward from the screw hole 13a due to the left-handed screw action. Strongly press the end face of the tie bar 5 with the tip end face. Therefore, a surface pressure is applied to the threaded portion between the tie bar nut 22 and the tie bar 5, and the threaded state of the tie bar nut 22 and the tie bar 5 are firmly fixed.

When the tie bar nut 22 and the tie bar 5 are engaged, the distance S is accurately maintained by the stopper 15, so that the engagement is performed smoothly and the surface pressure applied by the screw tightening lever 17 after engagement is always uniform. Become. Also, tie bar nut 22
Since the tightening is not due to the rotation of the tie bar nut 22 but due to the rotation of the pressing pin 16 which is separate from this, there is no risk of the tie bar nut 22 not being tightened due to play etc. or seizing. . Furthermore, since the tie bar nut 22 is supported on the fixed platen 3 side and can only be opened and closed,
The tie bar nut 22 and the tie bar 5 are easily aligned, and since there is no need to provide a flange on the tie bar 5, there is no stress concentration and there is no fear that the tie bar 5 will not come off.

Of course, the opening and closing of the tie bar nut 22 and the tightening by the surface pressure of the threaded portion of the tie bar nut 22 are performed in conjunction with each other, and the main body of the tie bar nut 22 is configured not to rotate, so that the splitting operation of the tie bar nut 22 can be performed instantly. It becomes possible to do it.

Although this embodiment shows an example in which the present invention is applied to a die-casting machine, it can also be applied to an injection molding machine. Further, the fluid pressure cylinder may be an air cylinder instead of the hydraulic cylinder 24.

Further, the same effect can be obtained even if the fixed plate 11 is not made independent but is integrated with the fixed platen 3.

Further, in the embodiment described above, the lower divided piece 21 of the tie bar nut 22 was made to touch the lower stay 12 at the opening limit of the tie bar nut 22.
This can be done by disposing a spacer tube between the fixed platen 3 on the outer periphery of the stay 12 and the screw receiving plate 13, or by placing the
Lower divided piece 21 of tie bar nut 22 is pressed so that parts of members 29c and 29d of link 29 are in contact with it.
It is also possible to make it serve as both a lowering limit stopper and a rotation stopper for the first link 29.

Further, in the embodiment, when the tie bar nut 22 is closed, the first link 29 and the second link 33 are vertically overlapped as shown in FIG. 2, and the pins 30, 32, 31 are positioned on the same vertical line, which means that when the tie bar nut 22 is closed, the pins 30, 32
are on the same vertical line, and only the pin 31 is slightly inserted into the lower stay 12 side, and the first
It is also possible to make the lower ends of the first link 29 and the second link 33 slope inward, so that they can be locked more reliably.

Further, in the embodiment described above, a plurality of chamfered portions 5b were provided on the outer circumferential surface of the protruding end of the tie bar 5, but these are attached by fixing a stopper slightly protruding inward to the end surface of the tie bar nut 22. When the tie bar nut 22 is closed, a stopper thereof may be engaged with one of the chamfered portions 5b to prevent the tie bar 5 from rotating. In that case, the stopper is tie bar nut 2.
It can also be attached to the lower divided piece 21 of 2 and engaged with the lower chamfered portion 5b of the tie bar 5.

〔Effect of the invention〕

As is clear from the above description, in the tie bar nut splitting device according to the present invention, the tie bar nut, which is divided into two halves and can be opened and closed, is pivotally attached to the fixed plate side and screwed together with the tie bar. A pressing pin, whose tip end faces the tie bar's protruding end surface, is screwed into the screw hole of the screw receiving plate provided opposite the protruding end surface so that it can move forward and backward, and the screw tightening lever fixedly supported by the pressing pin is connected to the fluid pressure cylinder. At the same time, the four-bar link formed by connecting the free ends of the two divided pieces of the tie bar nut with two links is engaged with the working end of the piston rod while moving forward and backward. The opening and closing of the tie bar nut and the tightening by surface pressure of the threaded part of the tie bar nut are performed continuously in the front and rear parts of one cylinder. Since the tie bar nut does not rotate and is tightened by surface pressure from a pressing pin separate from the tie bar nut, the tie bar nut will not become difficult to tighten or seize due to play, etc., and the tie bar nut and tie bar This makes it easier to align the centers of the ties, allowing for smooth and firm tightening, and the tie bar nuts and tie bars do not wear out due to tightening, greatly improving durability. Furthermore, there is no need to provide a flange on the tie bar, and the flange is no longer bitten by concentrated stress, making it easier to remove the tie bar.

In addition, opening and closing of the tie bar nut and tightening by surface pressure of the threaded part of the tie bar nut are performed in a series of operations, and the main body of the tie bar nut is configured not to rotate, so that the splitting operation of the tie bar nut can be performed instantly. Can be done.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the tie bar nut splitting device according to the present invention, where Figure 1 is a side view thereof, Figure 2 is a sectional view along AA of Figure 1, and Figure 3 is a view of the tie bar nut being opened. FIG. 4 is a schematic side view of a die casting machine embodying the present invention, and FIG. 5 is a schematic side view showing the die casting machine with the tie bar removed. 3... Fixed plate, 5... Tie bar, 5a... Projecting end, 10... Tie bar nut dividing device, 11...
...Fixing plate, 13...Screw receiving plate, 13a...Screw hole, 16...Press pin, 16a...Threaded part, 17
...screw tightening lever, 17a...long hole, 19,3
0, 31, 32...pin, 20...upper split piece,
21...Lower split piece, 22...Tie bar nut,
24... Hydraulic cylinder, 26... Piston rod, 27... Metal fitting, 28... Pin, 29... First
Link, 29b...Groove, 33...Second link.

Claims (1)

[Claims] 1. A tie bar nut that is divided into two semicircular arc pieces, one end of which is pivoted to the fixed platen side and that is screwed into the threaded part of the tie bar and can be opened and closed; and a tie bar nut that is supported by the fixed platen side and faces the protruding end surface of the tie bar. a screw receiving plate having a screw hole substantially concentric with the tie bar; a pressing pin having a tip end surface facing the protruding end surface of the tie bar and having a threaded portion screwed into the screw hole so as to be able to move forward and backward; and the pressing pin. a screw tightening lever fixedly supported on the
The working end of the piston rod is engaged with the free end of the screw tightening lever, and a fluid pressure cylinder is supported on the fixed plate side, and the piston rod is pivoted on the free end of the one semicircular arc piece to move the piston rod forward and backward. a first link that engages with its working end midway;
A tie bar nut dividing device comprising: a second link that connects the free end of the link and the free end of the other semicircular arc piece and forms a four-bar link with the first link.