JPS62252653A - Dividing device for tie bar nut - Google Patents

Abstract

PURPOSE:To continuously execute opening, closing and screwing of a tie bar nut by screwing the freely openable and closable tie bar nut to the screw part of a tie bar, screwing a pressing pipe, the top end of which faces the end face of the tie bar in contact therewith, to a screw receiving plate to support a screwing lever and actuating the lever by a cylinder. CONSTITUTION:The screwing lever 17 oscillates to turn the pressing pin 16 in an unscrewing direction when a piston rod 26 of the cylinder 24 is retreated. The top end of the pin is then detached from the end face of the tie bar so that the tie bar nut 22 can be opened and closed. The piston rod 26, when kept retreated, engages with the 1st link 29 which in turn opens both halved pieces 20, 21 of the nut 22, thus unscrewing the nut from the screw part 16a of the bar 5. An operator, thereupon, removes the bar 5, exchanges dies, reinserts the bar 5 and advances the rod 26. The nut 22 is then closed to be screwed to the screw part 16a of the bar 5. Only the lever 17 turns on further advancing of the rod 26 and the pin 16 turns in the screwing direction and is brought into press contact with the end face of the bar 5.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an injection molding device such as a die-casting machine or an injection molding machine. This invention 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]

When replacing the mold in a die casting machine or injection molding machine, etc., if the dimensions of the mold are larger than the tie bar spacing, loosen and remove the tie bar nuts that secure the tie bars, and move the tie bars from the fixed plate to the movable plate. After pulling it out in the wrong direction and replacing the mold, insert the tie bar and tighten the tie bar nut. In this case, loosening and removing the heavy tie bar nuts, and installing and tightening them requires a lot of effort and is inefficient, so conventionally the tie bar nuts are formed in half to reduce temperature. Various tie bar nut splitting devices have been proposed that have a structure in which the tie bar is loosened and opened while being supported on a fixed platen, the tie bar is removed and inserted, and the tie bar nut is closed and tightened.

For example, in the system disclosed in Japanese Utility Model Publication No. 59-32449, a rotary plate whose movement in the axial direction is restricted is rotatably supported in a tie bar insertion hole of a fixed plate, and the tie bar is inserted into the inner hole. The piston rod of the cylinder is pivotally connected to the other end of a half-split tie bar nut whose one end is pivotally connected to this rotary plate, and by moving this piston rod forward and backward, the tie bar nut can be loosened and tightened. A link is provided between the free ends of both halves of the tie bar nut pieces, and the halves of the tie bar nut are 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-mentioned device in that it is provided with a rotary plate and a cylinder for rotating the half-split tie bar nut, but in addition to this, another cylinder is provided. is supported by a rotating plate,
The half-split tie bar nut is opened and closed by the movement of the piston rod through a seat trouble mechanism.

[Problem that the invention seeks to solve]

However, with such conventional tie bar nut splitting devices, the tie bar nut is loosened by turning it while being strongly tightened with a cylinder and applying surface pressure, which tends to wear out the pressure surface of the tie bar nut and rotary plate, resulting in poor durability. If there is axial play greater than the rotation angle due to machining errors or wear, rather than an unexpected mistake, the tie bar nut will not tighten sufficiently even if the cylinder is operated all at once, and adjustment will be impossible. There were problems such as the high level of machining accuracy required and the need for early parts replacement.

In addition, since the tie bar nut is supported by a fixed plate via a rotating plate, the tie bar nut and the core of the tie bar are exposed, and seizing can occur by rotating the tie bar nut each time the tie bar is inserted or removed. The problem was that it was easy. Furthermore, since the tie bar's 7 lange and the tie bar nut will be tightened so that the fixed plate is strongly clamped, stress will be concentrated on the 7 lange, and the 7 lange surface will dig into the tie bar's hole, making it difficult to remove the tie bar. there were.

[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. In the screw hole of the screw receiving plate provided oppositely,
A pressing pin whose tip surface is in contact with one end surface of the tie bar is screwed together so that it can move forward and backward, and a screw tightening lever is fixedly supported by this pressing pin, and the swinging end of this screw tightening lever is supported by the fixed plate side. the piston rod working end of the hydraulic cylinder, and the free ends of each half piece of the tie bar nut are connected by a first link and a second link whose both ends are pivotally connected to each other. A four-bar link is formed, and the working member of the piston rod and the first link are configured to engage 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 the metal part, the screw tightening lever swings and the press pin rotates in the screw tightening direction, and its tip separates from the protruding end surface of the tie bar, so that 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 retreat, 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 the threaded portion of the tie bar becomes unscrewed. After removing the tie bar and replacing it with a metal one, inserting the tie bar and moving the piston rod of the fluid pressure cylinder forward 8, the tie bar nut closes via the four-bar link and screws into the threaded part of the tie bar, and the piston By moving the rod forward, only the screw tightening lever rotates and the pressing pin rotates in the screw loosening 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. The threaded surface pressure of the threaded part is applied between the tie bar nut and the tie bar nut.

〔Example〕

1 to 5 show an example in which the tie bar nut dividing device according to the present invention is implemented in a die casting machine, FIG. 1 is a side view thereof, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 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. In the figure, die casting machine 1
A fixed platen 3 and another fixed platen 4 whose movement can be adjusted are erected on the machine base 2 of the machine base 2.
The four corners of are connected by tie bars 5. Three of the four tie bars 5 are fixed on the fixed platen 3 side with nuts 6, and the remaining one on the fixed platen 3 side is provided with a tie bar nut dividing device 10, which will be described later. Reference numeral 7 denotes a movable plate supported by the tie bar 5 so as to be able to move forward and backward with respect to the fixed plate 3, and between the movable plate 7 and the fixed plate 4,
A mold clamping device consisting of a trouble mechanism (not shown) is provided, and by moving the movable platen T forward and backward with this mold clamping device, the fixed mold 8 attached to the fixed platen 3 and the movable platen 7, respectively. The movable mold 9 is configured to be clamped and opened.

The tie bar 5 to which the tie bar nut splitting device 1o is attached is removably inserted into the tie bar hole 311 of the fixed plate 3 from the movable plate 7 side and protrudes outward. A fixing 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 between which a fixing plate 11 is connected by two flat stays 14 and the above-mentioned stay 12; A left-handed threaded hole 13a is provided in the center of the tie bar 5, facing each other at an interval shown by .

A plurality of chamfers 5b are provided on the protruding end of the tie bar 5, and a stopper 15 protruding from the screw receiving plate 13 is engaged with the upper chamfer 5b of these chamfers. It is configured to abut against the step surface of 5b and maintain the gap S accurately. Reference numeral 16 denotes a pressing pin with a square head 16b whose threaded 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, the screw receiving plate 13 and the fixing plate 1 are placed at the same height as the tie bar 5.
A tie bar nut 22, which is divided into an upper divided piece 20 and a lower divided piece 21 in the shape of a semicircular arc, is rotatably supported at one end and is provided on the pin 19 connected to the pin 19 so as to be openable and closable. When both the divided pieces 20 and 21 are closed as shown in FIG. On the other hand, a trunnion type hydraulic cylinder 24 as a fluid pressure cylinder is swingably supported on a connecting plate 23 which connects the upper ends of the screw receiving plate 13 and the fixing plate 11 via a bracket 25. An inverted U-shaped metal fitting 27 is integrally formed at the working end of the piston rod 2B facing downward. A pin 28 is provided at the lower end of the metal fitting 27, and this pin 28 engages with an elongated hole 17a provided at the free end of the screw tightening lever 17. When the piston rod 2B rises from the state shown in FIG. 2 to the state shown in FIG. rotate in the direction,
Further, when the piston rod 26 descends from the state shown in FIG. 3 to the state shown in FIG. .

When the pressing pin 16 rotates in the direction of tightening the left-hand screw, the pressing pin 1B separates from the end surface 5a of the tie bar 5, and the threaded surface pressure between the tie bar nut 22 and the tie bar 5 is released, and the tie bar nut 22 opens and closes. In addition, when the pressing pin 16 rotates in the direction of loosening the left-hand screw, the pressing pin 1B is pressed against the end surface 5a of the tie bar 5, and the threaded surface pressure of the tie bar nut 22 and the tie bar 5 is applied to each other. Constructed to be firmly fixed. 17b is a spacer.

The reference numeral 29 in the figure is a first link formed in an inverted shape and having one end pivotally connected to the free end of the upper split piece 20 of the tie bar nut 22 with a pin 30, which connects the two members. By fixing with bolts, it is formed into a U-shape when viewed from the side, and a metal fitting 27, which is the working end of the piston rod 26, clamps the thin wall portion 29a on the vertically long thin wall portion 29a. are engaged. A groove 29b is provided in the thin wall portion 29a to serve as a retaining portion for the pin 28.
During the movement of the piston rod 26 to rotate the pin 28 in the direction of tightening the left screw of the pressing pin 1B, the pin 28 and the groove 2
9b are configured to engage with each other. When the piston rod 2B further rises after the pin 28 and the groove 29b are engaged, the first link 29 rotates together with the piston rod 26. Further, 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 by an inverted T-shaped second link 33 whose both ends are pivotally connected by pins 31 and 32. The first link 29 and the second link 33 form a four-bar link with pins 19, 30, and 31°32 as four nodes. When the piston rod 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 opens until the lower divided piece 21 comes into contact with the stay 12.

The operation of the tie bar nut splitting device configured as above will be explained. During normal times, the piston rod 2B of the hydraulic cylinder 24 is lowered, as shown in FIGS. E), since the end face of the tie bar 5 is strongly pressed against the end face of the tie bar 5, the tie bar nut 22
and the tie bar 5 are fixed by the surface pressure of the threaded portion.

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 screw tightening lever 17 that engages with the lever 17 rotates clockwise in FIG. The surface pressure is released,
The tie bar nut 22 can be opened and closed. When the piston rod 26 continues to rise, the pin 2B engages with the groove 29b of the first +J link 29, and after this, the first link 29 and the upper divided piece 20 of the tie bar nut 22 are integrally moved around the pin 19. It rotates and opens until the upper divided piece 20 comes into contact with the stay 12. When the piston rod 26 is further raised, the first link 29 rotates clockwise around the pin 30, so that the lower divided piece 2
Rotate and open until 1 contacts the stay 12 (In this case, both divided pieces 2
0.21 open at the same time), the lower divided piece 21 may open first, but as a result both divided pieces 21 open until they come into contact with the stay 12 as shown in FIG. By opening the tie bar nut 22 in this way, the tie bar 5 can move forward and backward, so as shown in FIG. .9 will be exchanged.

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 2B of the hydraulic cylinder 24 from the state shown in FIG. At the same time as the first link 29 begins to rotate counterclockwise, the metal fitting 2 presses the end face of the first link 29 indicated by reference numeral 29C in FIG.
rotates in the counterclockwise direction in the figure around the base plate 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 290, 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 fitting 27 is End face 29CK?
By lowering Ei, the upper and lower divided pieces 20.21
closes. The upper and lower divided pieces 20.
21 is completely closed, and the tie bar nut 22 and tie bar 5 are screwed together. After this, the pin 17a leaves the bottom of the groove 29b and the piston rod 26 continues to descend further, so only the screw tightening lever 11 continues to rotate, and the pressing pin 16 moves inward from the screw hole 13a due to the left-handed screw action. Pull it out and apply strong pressure to the end surface of the tie bar 5 with its tip. Therefore, a surface pressure is applied to the threaded portion between the tie bar nut 22 and the tie bar 5, and they are firmly fixed in the threaded state.

When the tie bar nut 22 and the tie bar 5 are engaged, the spacing S between them 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. becomes. Furthermore, since the tie bar nut 22 is tightened not by the rotation of the tie bar nut 22, but by the rotation of the pressing pin 1B, which is separate from this, there is a risk that the tie bar nut 22 may not be tightened due to play, etc., and may seize. There is no. Furthermore, since the tie bar nut 22 is supported by the fixed platen 3 and only opens and closes, the tie bar nut 22
and tie bar 5 This core is easy to match, and tie bar 5 and 7
Since there is no need to provide a lunge, there is no stress concentration and there is no fear that the tie bar 5 will not come out.

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.

〔Effect of the invention〕

As is clear from the above description, in the dieper nut dividing device according to the present invention, a tie bar nut which is divided into two halves and can be opened and closed is pivoted to the fixed plate side and screwed to the tie bar, A pressing pin whose tip surface faces the protruding end surface of the tie bar is screwed into the screw hole of the screw receiving plate provided opposite to the protruding end surface of the tie bar so that it can move forward and backward, and the screw tightening lever fixedly supported by the pressing pin is screwed into the screw hole of the screw receiving plate provided opposite to the protruding end surface of the tie bar. A four-bar link formed by engaging the working end of the piston rod of the pressure cylinder and connecting the free ends of the two divided pieces of one tie bar nut with two links is engaged with the working end of the piston rod while moving back and forth. 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. Therefore, the tie bar nut does not rotate, and tightening is performed by surface pressure from a pressing pin separate from the tie bar nut, so there is no possibility of the tie bar nut not being tightened due to play, etc., or seizing, and the tie bar nut and tie bar are This alignment makes it easier to tighten, making tightening smooth and strong, and the tie bar nut and tie bar 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 7-lunge is no longer bitten by concentrated stress, making it easier to pull out the tie bar.

[Brief Description of the Drawings] Figures 1 to 5 show an embodiment of the tie bar nut dividing device according to the present invention, in which Figure 1 is a side view thereof, Figure 2 is a sectional view taken along line AA in Figure 1, and The figure is a sectional view corresponding to Figure 2 with the tie bar nut opened, Figure 4 is a schematic side view of a die casting machine embodying the present invention, and Figure 5 is a schematic side view showing the tie bar removed. It is. 3...Fixed plate, 5...Tie bar, 5a-...
Projecting end, 10... Tie bar rod dividing device, 11
...Fixing plate, 13...Screw receiving plate, 13a...
・Screw hole, 1B...Press pin, 16a'l...Thread part, 17...Screw tightening lever, 17a...Elongated hole, 19, 30, 31.32...Pin , 20...Fist/upper split piece, 21...lower split piece, 22...
Tie bar nut, 24... φ Hydraulic cylinder, 26...
...Piston rod, 27...Metal fittings, 2B...
Pin, 29... 1st link, 29a... Groove, 3
3...Second link.

Claims (1)

[Claims] A tie bar nut that is divided into two semicircular arc-shaped pieces, one end of which is pivotally attached to the fixed platen side and that is screwed into the threaded portion 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, and 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 freely advanced and retractable;
a screw tightening lever fixedly supported by the pressing pin; a fluid pressure cylinder supported on the fixed plate side by engaging the working end of the piston rod with the free end of the screw tightening lever;
a first link that is pivotally connected to the free end of the one semi-circular arc piece and engages with the working end of the piston rod while moving back and forth; a free end of the first link and the other semi-circular piece; A tie bar nut splitting device comprising: a second link connecting the free end of the tie bar nut to the free end of the tie bar nut and forming a four-bar link with the first link.