JP2003112345A - Mold clamping device of molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the mold clamping device of a molding machine constituted so that the damage of a key locking bolt can be prevented by simple constitution, the mold clamping device is prevented from becoming large in size or design cost or production cost is prevented from becoming high and a toggle pin can be prevented from getting out of a toggle pin insertion hole or falling off therefrom. SOLUTION: The mold clamping device of the molding machine has a pin having a key groove formed to the side surface in the vicinity of the end part thereof and attaching a revolving member in a freely revolvable manner, a pin support member having an insertion hole in which the pin is inserted and a screw hole formed to the side surface thereof, the falling-off preventing key 12 inserted in the key groove at one end thereof so as to be immovable with respect to the axial direction of the pin and having a bolt insertion hole provided to the other end thereof and the key locking bolt 13 screwed in the screw hole through the bolt insertion hole and elastically pressing the falling-off preventing key 12 to the side surface of the pin support member through a spring member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device for a molding machine.

[0002]

2. Description of the Related Art Conventionally, in a molding machine such as an injection molding machine, a resin heated and melted in a heating cylinder is injected at a high pressure to fill a cavity space of a mold device. A molded product is molded by cooling and solidifying the resin in the cavity space.

To this end, the mold device is composed of a fixed mold and a movable mold, and the mold clamping device moves the movable mold forward and backward to bring the movable mold into and out of contact with the fixed mold to open and close the mold. , Mold closing, mold clamping and mold opening can be performed. And the mold clamping device is
In general, a movable platen that holds a movable mold and a toggle mechanism that advances and retracts the movable platen are provided. The toggle mechanism has a base attached to a toggle support by a toggle pin and an electric motor attached to the toggle support. It is operated by moving the crosshead forward and backward by means of a motor-based expansion and contraction means, a hydraulic cylinder and the like.

FIG. 2 is a sectional view of a mounting portion of a conventional toggle mechanism to a toggle support.

In the figure, reference numeral 100 denotes a toggle support, which has a base portion fixed to a frame of an injection molding machine (not shown), and toggle pin arms 101 projecting toward the movable platen are connected to the upper and lower portions of the base portion. . The tip (right end in the figure) of the toggle pin arm 101 is divided into a plurality of pieces, for example, three pieces.

Further, the toggle pin arm 101 is formed with a toggle pin insertion hole into which the toggle pin 102 for rotatably attaching the toggle lever 103 located at the base of the toggle mechanism is inserted. A toggle pin insertion hole into which the toggle pin 102 is inserted is formed at the base of the toggle lever 103, and the toggle lever 103 is formed.
Is a bush 10 fitted in the toggle pin insertion hole.
It is rotatably attached to the toggle pin 102 via 4.

In order to prevent the toggle pin 102 from slipping out of the toggle pin insertion hole, a key groove is formed at one end of the toggle pin 102, and a retaining key 105 is fitted in the key groove. And
The retaining key 105 is fixed to the toggle pin arm 101 by a key retaining bolt 106. As a result, the toggle pin 102 becomes immovable in the axial direction,
It will not slip out of the toggle pin insertion hole.

[0008]

However, in the conventional mold clamping device, the key stop bolt 106 is in operation during operation.
May be damaged, and the toggle pin 102 may slip out of the toggle pin insertion hole, or may drop out when it is extremely heavy. If the mold clamping device is operated by continuing the operation of the molding machine with the toggle pin 102 coming out or coming out of the toggle pin insertion hole, the toggle pin arm 101 may be damaged or damaged, which is expensive. The toggle support 100 becomes unusable.

However, what causes the key stop bolt 106 to be damaged has not been clarified yet. That is, it has been unclear in the past what kind of force is applied to the key stop bolt 106 and what kind of force is applied to the key stop bolt 106 to damage the key stop bolt 106.
Therefore, the monitoring and inspection of the mold clamping device during the operation of the molding machine or at the time of predetermined inspection are strengthened, and the key stop bolt 1 is
No measures have been taken other than to detect the damage of 06 in advance.

The inventor of the present invention has found that a load is applied to the toggle pin 102 in the axial direction based on various experiments and observations. Conventionally, the toggle pin 1
In the case of No. 02, it is assumed that the load is applied in the direction perpendicular to the axis (left-right direction in the drawing), but it is not assumed that the load is applied in the axial direction (vertical direction in the drawing).

However, due to deformation of the toggle support 100 during operation of the mold clamping device, poor lubrication of the bush 104, etc., the toggle pins 102 are opposite to each other along the axial direction, as indicated by F1 and F2 in the figure. It was found that the directional loads were applied alternately and repeatedly.
When a load in the direction F2 is applied, the retaining key 105 is pressed against the toggle pin arm 101, so that no load is applied to the key stop bolt 106. On the other hand, when a load in the direction of F1 is applied, the retaining key 105 is separated from the toggle pin arm 101, so a tensile load is applied to the key retaining bolt 106. Then, it became clear that the tensile load causes breakage of the key stop bolt 106.

Therefore, in order to prevent the key stop bolt 106 from being damaged, it may be considered that the key stop bolt 106 has a large size to improve the strength. In this case,
The surrounding members such as the retaining key 105 and the toggle pin arm 101 also become large in size, and the size of the mold clamping device becomes large.
The manufacturing cost of the mold clamping device also increases. In addition, without using the retaining key 105, the toggle pin 1
It is conceivable to adopt a structure for preventing 02 from slipping out or falling out of the toggle pin insertion hole, but in this case, it is necessary to fundamentally change the structure of the toggle support 100, and the design of the mold clamping device is required. The cost and manufacturing cost increase.

According to the present invention, the problems of the conventional mold clamping device can be solved, and the key stop bolt can be prevented from being damaged with a simple structure, the size of the mold clamping device can be increased, and the design cost can be reduced. An object of the present invention is to provide a mold clamping device for a molding machine, which can prevent the toggle pin from slipping out or falling out of the toggle pin insertion hole without increasing the manufacturing cost.

[0014]

To this end, in the mold clamping device of the molding machine of the present invention, there is provided a key groove formed on the side surface near the end, and a pin for rotatably attaching the rotating member. A pin support member having an insertion hole into which the pin is inserted and a side surface formed with a screw hole, one end of which is inserted into the key groove so as not to move in the axial direction of the pin and the other end of which is a bolt. A lock key having an insertion hole and a key whose shaft end is screwed into the screw hole through the bolt insertion hole and elastically presses the lock key against the side surface of the pin support member via a spring member. With a stop bolt.

In the mold clamping device of another molding machine of the present invention, the rotating member is a toggle arm or a toggle lever, and the pin support member is a toggle support, a movable platen, a toggle arm, It is a toggle lever or a crosshead.

In still another mold clamping device of a molding machine of the present invention, the spring member further has an opening at the center thereof into which the key stop bolt is inserted.

In still another mold clamping device of a molding machine of the present invention, a pin for inserting a rotating member into which a pivot member is rotatably attached and having a key groove formed on the side surface near both ends is inserted. And a pin support member having side surfaces formed with screw holes and spaced apart in the axial direction of the pin, and one end of which is movably inserted in the key groove in the axial direction of the pin. A lock key having a bolt insertion hole at the other end and a shaft end screwed into the screw hole through the bolt insertion hole, and the lock key is fastened and fixed to each side surface of the pin support member. And a key stop bolt.

In still another mold clamping apparatus for a molding machine of the present invention, the rotating member is a toggle arm, or
It is a toggle lever, and the pin support member is a toggle support, a movable platen, a toggle arm, a toggle lever, or a crosshead.

In still another mold clamping device of a molding machine of the present invention, the key groove extends in the axial direction of the pin, and an outer surface of one end of the retaining key is an outer end surface of the key groove. The inner surface of the one end of the retaining key does not contact the inner end surface of the key groove.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 3 is a schematic view of the mold clamping device of the molding machine according to the first embodiment of the present invention, and FIG. 4 shows the arrangement of toggle pins of the mold clamping device of the molding machine according to the first embodiment of the present invention. It is a figure shown and it is a sectional view taken on the arrow A of Drawing 3.

In the figure, 43 is a fixed platen fixed to a frame (not shown), and 10 is the fixed platen 43.
And a toggle support as a toggle mechanism supporting device fixed to the frame with a predetermined distance therebetween.
Further, 45 is the fixed platen 43 and the toggle support 1
It is a tie bar as a plurality of, for example, four guide members installed between 0 and 0.

Reference numeral 41 denotes a movable platen as a movable mold supporting device which is arranged so as to face the fixed platen 43 and is movable along the tie bar 45 so as to be movable back and forth (movable in the left-right direction in the drawing). is there. Further, the fixed mold 44 is attached to the mold mounting surface of the fixed platen 43 facing the movable platen 41, and the movable mold 42 is mounted to the mold mounting surface of the movable platen 41 facing the fixed platen 43. It is attached.

A drive source for moving an ejector pin (not shown) may be attached to the rear end (left end in the figure) of the movable platen 41.

A toggle mechanism as a toggle-type mold clamping device is provided between the movable platen 41 and the toggle support 10, and a rear end of the toggle support 10 is used for mold clamping of an injection molding machine as a molding machine. A drive device 33 is attached as a drive means of the. The drive device 33 may be an expansion / contraction means using an electric motor such as a servo motor, or a hydraulic cylinder device including a hydraulic cylinder and a piston.

The driving device 33 has a connecting rod 32 that moves forward and backward, and a cross head 31 as a driven member is connected to the tip (right end in the figure) of the connecting rod 32. Therefore, the toggle mechanism can be operated by operating the drive device 33 to move the crosshead 31 connected to the tip of the connecting rod 32 forward and backward.

When the drive device 33 is an electric motor, a rotating ball screw shaft is provided instead of the connecting rod 32, and a ball nut that is screwed to the ball screw shaft is provided on the crosshead 31. Then, the ball screw portion can be configured. In this case, when the electric motor as the drive device 33 operates, the ball screw shaft rotates, and the non-rotating ball nut advances and retreats along the ball screw shaft to move the crosshead 31 forward and backward. Further, even if the drive device 33 is an electric motor, the ball screw portion is disposed inside the electric motor or at a position close to the electric motor, and the end portion of the connecting rod 32 is attached to the ball screw portion, The connecting rod 32 can be moved back and forth.

The toggle mechanism has a small toggle lever 35 having one end rotatably attached to the crosshead 31, and one end rotatably with respect to the toggle pin arm 11 of the toggle support 10. A large toggle lever 36 attached to the middle portion of the small toggle lever 35, the other end of which is rotatably attached to the small toggle lever 35, and one end of which is rotatably attached to the other end of the large toggle lever 36 and the other end of which is attached. The toggle arm 37 is rotatably attached to the movable platen 41.

A small toggle pin 38 is attached between the crosshead 31 and the small toggle lever 35 and between the large toggle lever 36 and the small toggle lever 35, and the toggle support 10 and the large toggle lever 36 are attached. , The toggle arm 37 and the large toggle lever 36, and the toggle arm 37 and the movable platen 41 are attached via a large toggle pin 39. Note that, as shown in FIG. 4, the large toggle pin 39 is restricted from moving in the axial direction by the retaining key 12.
Furthermore, it is desirable that the small toggle pin 38 also be restricted from moving in the axial direction by the retaining key 12.

As a result, the movable platen 41 is moved forward by operating the drive unit 33 to move the crosshead 31 connected to the tip of the connecting rod 32 forward (to the right in the figure). As the mold is closed, a mold clamping force is generated by multiplying the propulsive force by the drive unit 33 with a toggle magnification, and the mold clamping is performed by the mold clamping force.

Next, the mounting portion of the large toggle pin 39 to the toggle support 10 will be described.

FIG. 1 is a sectional view of a mounting portion of a large toggle pin to a toggle support according to the first embodiment of the present invention, and is an enlarged view of a B portion in FIG.

As shown in the drawing, the tip (right end in the figure) of the toggle pin arm 11 of the toggle support 10 functioning as a pin support member is divided into a plurality, for example, three. Then, a large toggle pin 39 is inserted into the toggle pin arm 11 as a pin for rotatably attaching one end (the left end in the drawing) of the large toggle lever 36 functioning as a toggle lever as a rotating member. A toggle pin insertion hole as a hole is formed. And
The large toggle lever 36 has a toggle pin insertion hole into which the large toggle pin 39 is inserted, and the large toggle lever 36 has the bush 16 fitted in the toggle pin insertion hole.
It is rotatably attached to the large toggle pin 39 via.

In order to prevent the large toggle pin 39 from slipping out of the toggle pin insertion hole, a key groove is formed on the side surface near one end (lower end in the figure) of the large toggle pin 39. One end of the retaining key 12 is inserted into the key groove. Here, the retaining key 1
2 is immovable in the axial direction of the large toggle pin 39. An insertion hole into which the key stop bolt 13 is inserted is formed at the other end of the retaining key 12.
Then, the shaft end of the key stop bolt 13 passes through the insertion hole and is screwed into a screw hole formed on the side surface of the toggle pin arm 11. Therefore, the retaining key 12 is elastically pressed against the side surface of the toggle pin arm 11 by the key retaining bolt 13.

That is, a spring member 15 is provided around the shaft of the key stop bolt 13 and has an opening for inserting the key stop bolt 13 at the center of a disc spring, a coil spring, or the like.
A cylindrical distance pipe 14 is attached so as to be movable in the axial direction. Therefore, the lock key 1
2 is elastically pressed to the lower side surface of the toggle pin arm 11 in the figure by the spring force of the spring member 15 applied via the distance pipe 14. As a result, the large toggle pin 39 becomes immovable in the axial direction with a load smaller than the spring force of the spring member 15, and thus does not slip out of the toggle pin insertion hole.

In this case, when a load along the upward axial direction in the figure is applied to the large toggle pin 39, the load is received by the lower side surface of the toggle pin arm 11 in the figure through the retaining key 12. To be Therefore, since the large toggle pin 39 does not move upward in the drawing due to the load, it does not slip out of the toggle pin insertion hole.

On the other hand, when a load along the downward axial direction in the figure is applied to the large toggle pin 39, the load is passed through the retaining key 12 and further the distance pipe 14
It is received by the bolt head of the key stop bolt 13 via the spring member 15. In this case, if the load is equal to or greater than the spring force of the spring member 15, the spring member 15 is compressed, so that the large toggle pin 39 slightly moves downward in the drawing. However, since the amount of movement is small, the toggle pin arm 11 is not damaged or broken. In addition, as described in "Problems to be Solved by the Invention", since loads in the axial direction applied to the large toggle pin 39 are alternately and repeatedly applied in opposite directions, a downward load is applied for a short time. It disappears at and an upward load is applied. Therefore, since the spring member 15 is restored from the compressed state in a short time, the large toggle pin 39 moved downward is also returned to the original position in a short time.

When the downward load is an impact load, the impact is buffered by the spring member 15 and transmitted to the bolt head of the key stop bolt 13. Therefore, since the impact load that causes the breakage of the key stop bolt 13 is not directly transmitted to the bolt head but is transmitted in a buffered manner, the downward load does not cause damage to the key stop bolt 13. . Further, since the downward load disappears in a short time, the energy of the impact load buffered by the spring member 15 can be small. Therefore, the spring member 15 may be small.

As described above, in the present embodiment, the large toggle pin 39 is fixed to the retaining key 12 which is fixed by being pressed against the side surface of the toggle pin arm 11 by the key retaining bolt 13 to which the spring member 15 and the distance pipe 14 are attached. The axial movement is restricted by.

Therefore, even though the structure is simple, the key stop bolt 13 will not be damaged by the load applied to the large toggle pin 39 along the axial direction.
Further, since it is not necessary to increase the strength by making the key stop bolt 13 large in size, neither the size of the mold clamping device nor the manufacturing cost of the mold clamping device is increased. Furthermore, since the structure of the conventional mold clamping device can be adopted as it is, the design cost and manufacturing cost of the mold clamping device will not increase.

Next, a second embodiment of the present invention will be described. It should be noted that description of the same structure and the same operation as those of the first embodiment will be omitted.

FIG. 5 is a sectional view of an attachment portion of the large toggle pin to the toggle support according to the second embodiment of the present invention, which is an enlarged view of a portion C of FIG.

In the present embodiment, as shown in the figure, the distance pipe 14 (FIG. 1) is not attached around the axis of the key stop bolt 13 only in the first embodiment. Is different from. In this case, the length of the shaft of the key stop bolt 13 can be shortened by the distance pipe 14, and the structure of the mold clamping device can be made compact.

Next, a third embodiment of the present invention will be described. It should be noted that description of the same structure and the same operation as those of the first and second embodiments will be omitted.

FIG. 6 is a cross-sectional view of an attachment portion of the large toggle pin to the toggle support according to the third embodiment of the present invention, and is an enlarged view of a B portion in FIG.

In the present embodiment, as shown in the figure, key grooves 17a and 17b are formed on the side faces near both ends (the upper end and the lower end in the figure) of the large toggle pin 39, and the key grooves 17a and 17b are formed. One ends of the retaining keys 12a and 12b are respectively inserted into 17b so as to be movable in the axial direction of the large toggle pin 39.

Here, an insertion hole into which the key stop bolts 13a and 13b are inserted is formed at the other ends of the retaining keys 12a and 12b. And the key stop bolt 1
The shaft ends of 3a and 13b pass through the insertion hole and are screwed into screw holes formed on both side surfaces of the toggle pin arm 11. Therefore, the retaining keys 12a and 12b
Is fixed to the side surface of the toggle pin arm 11 by key fixing bolts 13a and 13b. The side surface is formed on the toggle pin arm 11 at a position in the axial direction of the large toggle pin 39 and at a position facing the key grooves 17a and 17b.

In this case, unlike the first and second embodiments, the spring members 15 (FIG. 1) are not attached to the shafts of the key lock bolts 13a and 13b, and the lock key is not provided. 12a and 12b are immovably fixed to the side surface of the toggle pin arm 11 by key fastening bolts 13a and 13b. The retaining keys 12a and 12b have the same size and shape, and the key retaining bolts 13a and 13b also have the same size and shape.

On the other hand, the key grooves 17a and 17b have the same shape and size as each other and are formed so as to extend in the axial direction of the large toggle pin 39. Here, the axial dimension of the large toggle pin 39 of the key grooves 17a and 17b is t1 +, respectively, than the axial dimension of the large toggle pin 39 of the retaining keys 12a and 12b.
It is longer by t2.

When the large toggle pin 39 is in the neutral position, the positional relationship between the key grooves 17a and 17b and the retaining keys 12a and 12b is as shown in the figure. That is, the distance between the outer (lower side in the figure) surface of the retaining key 12a and the outer (lower side in the figure) end surface of the key groove 17a, and the outer (upper side in the figure) surface of the retaining key 12b and the outer side of the key groove 17b. The distance from the end face (upper side in the drawing) is the same value t1. Further, the distance between the inside (upper side in the figure) surface of the retaining key 12a and the inner (upper side in the figure) end surface of the key groove 17a, and the retaining key 1
The distance between the inner (lower side in the figure) surface of 2b and the inner (lower side in the figure) end surface of the key groove 17b is the same value t.
It is 2. Furthermore, t1 <t2.

Therefore, when a load along the upward axial direction in the figure is applied to the large toggle pin 39 and the large toggle pin 39 moves upward, the outer surface of the retaining key 12a and the outer end surface of the key groove 17a are separated from each other. Abut, the load is
The toggle pin arm 11 is received by the lower side surface of the toggle pin arm 11 in FIG. for that reason,
Since the large toggle pin 39 does not move upward in the drawing due to the load, it does not slip out of the toggle pin insertion hole. At this time,
Since the inner side surface of the retaining key 12b and the inner end surface of the key groove 17b do not come into contact with each other, an upward load is not applied to the key retaining bolt 13b via the retaining key 12b. Therefore, due to the upward load, the key stop bolt 13b
Will not be damaged.

On the other hand, when a load along the downward axial direction in the drawing is applied to the large toggle pin 39 and the large toggle pin 39 moves downward, the outer surface of the retaining key 12b and the outer end surface of the key groove 17b are Abut, and the load is
It is received by the side surface of the toggle pin arm 11 on the upper side in the drawing through the retaining key 12b. for that reason,
Since the large toggle pin 39 does not move downward in the figure due to the load, it does not slip out of the toggle pin insertion hole. At this time,
Since the inner side surface of the retaining key 12a and the inner end surface of the key groove 17a do not abut, a downward load is not applied to the key retaining bolt 13a via the retaining key 12a. Therefore, the key stop bolt 13b is applied by the downward load.
Will not be damaged.

As described above, in the present embodiment, the large toggle pin 39 is prevented from moving in the axial direction by the retaining keys 12a and 12b fixed to the side faces on both sides of the toggle pin arm 11 by the key retaining bolts 13a and 13b. To be done. The key grooves 17a and 17b into which the lockout keys 12a and 12b are fitted are provided with large toggle pins 39.
Of the retaining keys 12a and 12b and the key grooves 17a and 17b when the large toggle pin 39 moves in the axial direction due to a load along the axial direction.
The outer end surfaces of the retaining keys 12a and 12b and the outer end surfaces of the key grooves 17a and 17b are in contact with each other to receive the load.

Therefore, even though the structure is simple, the key stop bolts 13a and 13b are not damaged by the load applied to the large toggle pin 39 along the axial direction. Further, since it is not necessary to increase the strength by making the key fastening bolts 13a and 13b large in size, the size of the mold clamping device does not increase and the manufacturing cost of the mold clamping device does not increase. Furthermore, since the structure of the conventional mold clamping device can be adopted as it is, the design cost and manufacturing cost of the mold clamping device will not increase.

Although the large toggle pin 39 for attaching the toggle support 10 and the large toggle lever 36 has been described in the first to third embodiments, the large toggle pin 39 for attaching the toggle arm 37 and the large toggle lever 36 is described. , And toggle arm 37 and movable platen 41
Also in the case of the large toggle pin 39 for attaching and,
With the same configuration as that of the third embodiment, axial movement is restricted. The same applies to the small toggle pin 38 to which the crosshead 31 and the small toggle lever 35 are attached and the small toggle pin 38 to which the large toggle lever 36 and the small toggle lever 35 are attached. In this case, the movable platen 41, the toggle arm 37, the toggle lever (the large toggle lever 36 and the small toggle lever 35), or the crosshead 31 functions as a pin support member, and the toggle arm 3
7 or the toggle lever (the large toggle lever 36 and the small toggle lever 35) functions as a rotating member.

In this embodiment, the horizontal type injection molding machine in which the movable platen moves in the horizontal direction (horizontal direction) has been described. However, in the mold clamping device of the present invention, the movable platen is set in the vertical direction (vertical direction). The present invention can also be applied to a vertical injection molding machine that moves in the direction). Further, in addition to the injection molding machine, the mold clamping device of the present invention includes a die cast machine, an I
It can also be applied to a molding machine such as a J-sealing press.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention, and they are not excluded from the scope of the present invention.

[0058]

As described in detail above, according to the present invention, the mold clamping device of the molding machine is provided with the key groove formed on the side surface near the end, and the rotating member is rotatable. A pin for attachment, an insertion hole into which the pin is inserted, and
A pin support member having a side surface in which a screw hole is formed, one end of which is immovably inserted into the key groove in the axial direction of the pin and the other end of which has a bolt insertion hole.
The shaft end is screwed into the screw hole through the bolt insertion hole, and has a key stop bolt that elastically presses the removal prevention key against the side surface of the pin support member via a spring member.

In this case, the movement of the pin in the axial direction is restricted by the retaining key pressed against the side surface of the pin supporting member by the key retaining bolt to which the spring member is attached. Therefore, even though the structure is simple, the key stop bolt will not be damaged by the load applied to the pin along the axial direction. Further, since it is not necessary to increase the strength by making the key stop bolt large in size, the size of the mold clamping device does not become large and the manufacturing cost of the mold clamping device does not increase. Furthermore, since the structure of the conventional mold clamping device can be adopted as it is, the design cost and manufacturing cost of the mold clamping device will not increase.

In another mold clamping device of a molding machine, a key groove formed on the side surface near both ends is provided, a pin for rotatably attaching a rotating member, an insertion hole into which the pin is inserted, And a pin support member having side surfaces formed with screw holes and spaced apart in the axial direction of the pin, one end of which is inserted into the key groove so as to be movable in the axial direction of the pin, and the other end of which is Retaining key having a bolt insertion hole in its portion, and a key stop bolt having a shaft end screwed into the screw hole through the bolt insertion hole and tightening and fixing the retaining key on each side surface of the pin support member. Have and.

In this case, the movement of the pin in the axial direction is restricted by the retaining keys fixed to both side surfaces of the pin supporting member by the key retaining bolts. And, the key grooves into which the respective retaining keys are inserted extend in the axial direction of the pin,
When a load is applied along the axial direction to move the pin in the axial direction, the inner surface of the retaining key and the inner end of the key groove do not contact, but the outer surface of the retaining key and the outer end of the key groove Are in contact with each other to receive the load.

Therefore, even though the structure is simple, the key stop bolt is not damaged by the load applied to the pin along the axial direction. Further, since it is not necessary to increase the strength by making the key stop bolt large in size, the size of the mold clamping device does not become large and the manufacturing cost of the mold clamping device does not increase. Furthermore, since the structure of the conventional mold clamping device can be adopted as it is, the design cost and manufacturing cost of the mold clamping device will not increase.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a mounting portion of a large toggle pin to a toggle support according to a first embodiment of the present invention, which is an enlarged view of a B portion in FIG.

FIG. 2 is a cross-sectional view of an attachment portion of a conventional toggle mechanism to a toggle support.

FIG. 3 is a schematic view of a mold clamping device of the molding machine according to the first embodiment of the present invention.

FIG. 4 is a view showing the arrangement of toggle pins of the mold clamping device of the molding machine according to the first embodiment of the present invention, and is a cross-sectional view taken along the arrow A in FIG.

FIG. 5 is a cross-sectional view of an attachment portion of a large toggle pin to a toggle support according to the second embodiment of the present invention, which is an enlarged view of portion C of FIG.

FIG. 6 is a cross-sectional view of an attachment portion of a large toggle pin to a toggle support according to a third embodiment of the present invention, which is an enlarged view of portion B in FIG.

[Explanation of symbols]

10 toggle support 11 Toggle pin arm 12, 12a, 12b Locking key 13, 13a, 13b Key stop bolt 15 Spring member 17a, 17b Keyway 31 crosshead 35 Small toggle lever 36 large toggle lever 37 Toggle Arm 38 Small toggle pin 39 Large toggle pin 41 Movable platen

Claims (6)

[Claims] 1. (a) A pin having a key groove formed on a side surface near the end portion for rotatably attaching a rotating member, (b) an insertion hole into which the pin is inserted, and a screw. A pin support member having a side surface having a hole formed therein, (c) a lock key having one end immovably inserted into the key groove in the axial direction of the pin and having a bolt insertion hole at the other end.
(D) A key stop bolt having a shaft end screwed into the screw hole through the bolt insertion hole and elastically pressing the retaining key to a side surface of the pin support member via a spring member. Clamping device for molding machine. 2. The rotating member is a toggle arm or
The mold clamping device for a molding machine according to claim 1, wherein the mold support device is a toggle lever, and the pin support member is a toggle support, a movable platen, a toggle arm, a toggle lever, or a crosshead. 3. The mold clamping device for a molding machine according to claim 1, wherein the spring member has an opening at the center thereof into which the key stop bolt is inserted. 4. (a) A pin having key grooves formed on side surfaces near both ends, for rotatably mounting a rotating member, and (b) an insertion hole into which the pin is inserted, and a screw. A pin support member having a side surface formed with a hole and spaced apart in the axial direction of the pin; and (c) one end portion inserted into the key groove so as to be movable in the axial direction of the pin,
A retaining key having a bolt insertion hole at the other end, and (d) a shaft end screwed into the screw hole through the bolt inserting hole, and the retaining key is tightened on each side surface of the pin support member, A mold clamping device for a molding machine, comprising a key stop bolt for fixing. 5. The rotating member is a toggle arm or
The mold clamping device of the molding machine according to claim 4, wherein the mold support device is a toggle lever, and the pin support member is a toggle support, a movable platen, a toggle arm, a toggle lever, or a crosshead. 6. The key groove extends in the axial direction of the pin, an outer surface of one end of the retaining key abuts an outer end surface of the key groove, and an inner surface of one end of the retaining key is The mold clamping device for a molding machine according to claim 4 or 5, which does not come into contact with the inner end surface of the key groove.