JP2565060B2 - Safety equipment for injection molding machines - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for an injection molding machine which avoids danger by closing a side of a moving space of a movable plate which is moved by a mold clamping device with a safety door for operation and a safety door for non-operation.

[0002]

2. Description of the Related Art Generally, in injection molding machines, safety doors are provided on the front side (operating side) and the rear side (opposite operating side) of the moving space of a movable plate, and the safety doors are closed. In some cases, it is possible to move the movable platen by the mold clamping device.
Moreover, when the safety door is in the open state, a safety means is attached to prevent the movable platen from being clamped by the mold clamping device to prevent personal injury.

By the way, there are three types of safety means, electric type, hydraulic type, and mechanical type, and the safety side of the operating side, which is frequently opened and closed, is provided with the three types of safety means to enhance safety. Also, the anti-operation side safety door, which is rarely opened and closed, is made up by only one kind of safety means such as electric type. Therefore, with regard to the anti-operation side safety door, if there is a failure of only one safety measure, it is very dangerous because the movable plate may move while the anti-operation side safety door is open. is there. Although it is possible to improve safety by providing three kinds of safety means also on the anti-operation side safety door like the operation side safety door, the structure becomes complicated and the cost is not economical.

Therefore, an arm is provided on one of the operation-side safety door and the anti-operation-side safety door, and a stopper is provided on the other, and the arm and the stopper are provided when the anti-operation-side safety door is opened and when the operation-side safety door is closed. Has been proposed (Japanese Unexamined Patent Publication No. 50-64356), in which the two are engaged with each other to follow the other safety door.

Separately from the above, a rotary shaft is supported between bearings on the machine body side so as to be rotatable in the circumferential direction between both safety doors, and one end of the rotary shaft is in a closed state. The operation side lever is pushed by the safety door when the operation side safety door is opened to rotate the rotation shaft, and the other side of the operation side safety door is opened when the closed anti-operation side safety door is opened. A safety device has been proposed in which the anti-operation side levers that are pushed by the door to turn the turning shaft are fixed, and the above-mentioned levers are provided with an electric detector and a hydraulic detector that are the main safety means. (Japanese Utility Model Publication No. 3-35540).

In the above two safety devices, the safety means can be shared by the operating side safety door and the non-operating side safety door.

[0007]

However, in the former safety device, when the operation side safety door is closed and the counter operation side safety door is opened, other safety doors that do not need to be moved must be moved more than necessary. There are things that must be done, and there are unreasonable complaints. In the case of the latter safety device, both safety doors are completely independent, so there is no problem as described above, but the mechanical safety means described in the description of the present invention is shared by both safety doors. I can't let you do it.

The present invention relates to an injection molding machine capable of sharing all safety means provided on the operating side safety door with the anti-operating side safety door and suppressing the following movement of the safety door to a minimum. The purpose is to provide a safety device.

[0009]

In order to achieve the above object, the present invention is directed to an operating side and an operating side of a movable space of a movable platen moved by a mold clamping device, an operating side safety door and an operating side. An operation-side safety door is individually provided so as to be movable in the moving direction of the movable platen.At least the operation-side safety door is clamped by the mold clamping device when the operation-side safety door is closed. In the safety device of the injection molding machine equipped with a safety device that enables movement and that prevents the mold clamping movement of the movable plate by the mold clamping device when the operation safety door is in the open state, Between the anti-operation side safety door, a rotation shaft is supported by a bearing on the machine body side provided with the mold clamping device and the like so as to be rotatable in the circumferential direction, and at one end of the rotation shaft, When the closed operation side safety door is opened, it is pushed by the operation side safety door to rotate the rotating shaft. An anti-operation that fixes the operation-side lever and that pushes the anti-operation side safety door when the closed anti-operation side safety door is opened at the other end of the above-mentioned turning shaft to turn the turning shaft. Side lever is fixed and the operation side safety door receives the rotation of the rotating shaft via the operation side lever only when the closed anti-operation side safety door is opened. The interlocking claw that opens the tiny distance within a certain fixed range is provided.

[0010]

When the closed anti-operation side safety door is opened, the anti-operation side lever is pushed by the anti-operation side safety door to rotate. Therefore, the operation-side lever is rotated through the rotation shaft, and the interlocking pawl is pushed to open the closed operation-side safety door for a minute distance within a fixed range . Therefore, the safety means attached to the operation side safety door works to prevent the movable platen from being clamped by the mold clamping device. At this time, the operating-side safety door does not follow the movement range of the lever.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The attached drawings show an embodiment of a safety device for an injection molding machine according to the present invention, in which reference numeral 1 is a machine body of the injection molding machine. The machine body 1 includes a mold clamping device 3 mainly including a hydraulic cylinder 2 and a toggle mechanism (not shown), a mold device 6 mainly including a fixed platen 4 and a movable platen 5 (FIG. 9), and heating. A plasticizing device 8 mainly including the cylinder 7 is provided. The movable platen 5 is moved left and right in FIG. 9 by the mold clamping device 3. An operation side safety door 9 and an anti-operation side safety door 10 are provided on the front side and the rear side of the moving space of the movable platen 5 so as to be movable in the moving direction of the movable platen 5 (left and right direction in FIGS. 1 and 2). There is. The basic structure of the injection molding machine is well known.

The machine body 1 has a pair of bearings 11, 1.
2 is provided, and the bearings 11 and 12 thereof have a rotating shaft 1
3 is supported. The rotating shaft 13 is horizontally provided orthogonal to the moving directions of the movable plate 5 and the safety doors 9 and 10.
It is rotatable in the circumferential direction. An operation-side lever 14 is fixed to the front end of the rotating shaft 13, and an anti-operation-side lever 15 is fixed to the rear end.

Each lever 14, 15 has a roller 16,
Have 17 individually. The operating-side lever 14 projects from the retracted-side moving surface of the closed operating-side safety door 9, and the anti-operating-side lever 15 projects from the retracted-side moving surface of the closed anti-operating-side safety door 10. A hook-shaped interlocking claw 18 that is pressed by the roller 16 is attached to the end surface of the operation-side safety door 9 on the retracted side.

In the above structure, when the operation side safety door 9 is moved to the left in FIG. 4 and opened, the operation side lever 14 is tilted to the left by a certain angle in the figure and the rotary shaft 13 is rotated counterclockwise. When the anti-operation side safety door 10 is rotated and moved to the left in FIG. 5 to open it, the anti-operation side lever 15 tilts to the left by a certain angle in the same manner as described above to rotate the rotary shaft 13. At this time, the rotation of the rotation shaft 13 also rotates the other levers 15 and 14. Therefore, when opening the anti-operation side safety door 10 ,
Only, since the press operating side lever 14 by a distance of a range in which the engagement does not come off with it an interlocking claw 18 in the roller 16, open requires minimal primary safety door 9, also the secondary safety door
When closing the operation side safety door 9 which is slightly opened in the state where 10 is opened , the interlocking pawl 18 pushes the roller 16 and tries to rotate the counter operation side lever 15 together with the operation side lever 14. , Roller 17 of lever 15 on the non-operation side
However, since the upright (return) rotation of the anti-operation side lever 15 is stopped by coming into contact with the lower surface of the anti-operation side safety door 10, it is impossible to completely close the operation side safety door 9, and thus the anti-operation side safety. It can be dealt with by knowing that the door 10 is opened.

The operation side safety door 9 has an electric safety means 20 (FIG. 6) and a hydraulic safety means 21 (FIG. 8).
And mechanical safety means 22 (FIGS. 9 and 10) are attached,
Further, an electric safety means 23 (FIG. 7) is attached to the counter operation side safety door 10.

The electrical safety means 20 is mainly composed of a normally closed type limit switch 24 and a normally open type limit switch 25 arranged on the moving surface of the operating side safety door 9, and the other electrical safety means 23 is normally used. The open type limit switch 26 is mainly used. The pair of limit switches 24 and 25 are turned on when the operating-side safety door 9 is closed, and turned off when the operating-side safety door 9 is opened to detect opening / closing of the safety door 9. Further, the limit switch 26 is turned on when the anti-operation side safety door 10 is closed, and is turned off when it is opened to detect opening / closing of the safety door 10.

Then, the above three limit switches 2
4, 25 and 26 are connected in series with each other to a mold clamping command circuit (not shown) that switches electromagnetic valves provided in the hydraulic circuit of the hydraulic cylinder 2. Therefore, when the two safety doors 9 and 10 are closed and the three limit switches 24, 25 and 26 are not turned on, the solenoid valve is switched and the movable platen 5 moves in the mold clamping. And the safety of workers is maintained.

The hydraulic safety means 21 mainly includes a cam valve 27 provided in the hydraulic circuit of the hydraulic cylinder 2. When the rotating shaft 13 is rotated by the opening movement of the closed safety doors 9 and 10, the cam valve 27 has its spool pushed by the pressing piece 28 attached to the rotating shaft 13 and the hydraulic circuit of the hydraulic cylinder 2. Shut off. Therefore, also in this case, the mold clamping movement of the movable platen 5 is prevented when the safety door is open.

Further, the mechanical safety means 22 includes a movable plate 5
The safety bar 30 having a screw structure is fixed by a nut 31, and a stopper 32 is provided on the fixed plate 4 so as to be rotatable up and down by a pin 33. When the operation side safety door 9 is opened, the stopper 32 is secured to the safety bar 30. Of the movable platen to prevent the movable plate 5 from being clamped, and when the safety door 9 is closed,
The stopper 32 pushes its roller 34 by the dog 35 of the safety door 9, and the safety bar 30 as shown by the chain double-dashed line in FIG.
It is configured so that the movable platen 5 can be freely clamped by rotating upward from the moving surface. Reference numeral 36 is a tie rod, and 37 is a cover.

Next, the operation of the safety device of the injection molding machine according to the present invention constructed as described above will be described. Each safety door 9,
When the operation side safety door 9 is opened from the state in which 10 is closed, the limit switches 24 and 25 are turned off, the cam valve 27 shuts off the hydraulic circuit of the hydraulic cylinder 2, and the stopper 32 falls down to ensure safety. The moving surface of the bar 30 is shut off. Therefore, the mold clamping movement of the movable platen 5 is triple blocked by the safety means 20, 21, 22.

When the anti-operation side safety door 10 is opened in a state where the safety doors 9 and 10 are closed, the anti-operation side lever 15 is pushed by the safety door 10 and pivots to pivot the pivot shaft 13. To do so, the operating side lever 14 also rotates and pushes the interlocking pawl 18 to open and move the operating side safety door 9 by a distance within a minute fixed range . Therefore, the limit switch 26 is turned off, and the safety means 20 provided on the operation side safety door 9 are
21 and 22 also work to prevent the movable platen 5 from being clamped.

When the anti-operation side safety door 10 is opened beyond the range of rotation of the levers 14 and 15, the roller 17 of the anti-operation side lever 15 has the anti-operation side safety as shown by the chain double-dashed line in FIG. Since the upright (return) rotation of the anti-operation side lever 15 is stopped by coming into contact with the lower surface of the door 10, the operation side safety door 9 cannot be completely closed, and the safety means 20, 21, 2 described above are not closed.
It remains open to the minimum extent necessary for 2 to operate. From this, it can be dealt with by knowing that the anti-operation side safety door 10 is opened.

In the present invention, each safety means 20, 2
The specific structure of 1, 22, 23 and the number of facilities are not limited to the above, but are arbitrary. Further, the safety means 23 of the anti-operation side safety door 10 can omit this.

[0024]

As described above, according to the present invention, the operation side safety door and the anti-operation side safety door are movable on the operation side and the anti-operation side of the moving space side of the movable platen moved by the mold clamping device. Each of them is provided individually movably in the moving direction of the board, and at least the operation-side safety door enables the mold clamping movement of the movable board by the mold clamping device when the operation-side safety door is in the closed state. When the side safety door is in the open state, in the safety device of the injection molding machine equipped with safety means to prevent the mold clamping movement of the movable plate by the mold clamping device, the safety door of the operation side and the safety door of the non-operation side A rotary shaft is supported between bearings on the machine body side provided with the mold clamping device and rotatably in the circumferential direction, and one end of the rotary shaft has a closed operation side. When the safety door is opened, the operation side is pushed by the safety door and rotates the rotation shaft. A bar is fixed, and at the other end of the rotating shaft, an anti-operation side lever for rotating the rotating shaft by being pushed by the anti-operation side safety door when the closed anti-operation side safety door is opened. Is fixed, and the operation side safety door receives the rotation of the rotating shaft via the operation side lever only when the closed anti-operation side safety door is opened. Since the interlocking pawl that opens the door to a small fixed range is provided, the safety means attached to the operating side safety door will be shared with the anti-operating side safety door, and a simple structure Therefore, the safety of the injection molding machine can be further enhanced.

[Brief description of drawings]

FIG. 1 is a front view of an injection molding machine to which the present invention is applied.

FIG. 2 is a plan view of a main part showing an embodiment of a safety device for an injection molding machine according to the present invention.

[3] Also, a side view of the main part.

FIG. 4 is a front view showing a relationship between an operation side safety door and an operation side lever.

FIG. 5 is a view to view the relationship between the secondary safety door and the side opposite the operation side lever as seen from the operation side safety door side.

FIG. 6 is a front view showing a relationship between an operation side safety door and a limit switch.

FIG. 7 is a view to view the relationship between the secondary safety door and limit switch as seen from the operation side safety door side.

FIG. 8 is a hydraulic circuit diagram of hydraulic safety means.

FIG. 9 is a front view of a mechanical safety means.

FIG. 10 is a side view showing the relationship between the stopper of the mechanical safety means and the safety bar and the like.

Claims (1)

(57) [Claims] 1. An operating-side safety door and an anti-operating-side safety door are individually movably provided in a moving direction of a movable platen on an operating side and an anti-operating side of a moving space of a movable platen moved by a mold clamping device. At least on the operation side safety door, when the operation side safety door is closed, the movable platen can be moved by the mold clamping device, and when the operation side safety door is open, In a safety device of an injection molding machine provided with a safety means for preventing a mold clamping movement of a movable plate by a mold clamping device, a rotating shaft is provided between the operation side safety door and the counter operation side safety door. It is rotatably provided in the circumferential direction by being supported by a bearing on the machine body side provided with a fastening device, and the operating side is opened at one end of the rotating shaft when the closed operating side safety door is opened. The operation side lever that is pushed by the safety door to rotate the rotating shaft is fixed, and At the other end, a counter operation side lever that is pressed by the counter operation side safety door to rotate the pivot shaft when the counter operation side safety door in the closed state is opened is fixed, and the operation side safety door is Only when the closed anti-operation side safety door is opened, the door receives the rotation of the rotating shaft via the operation side lever, and the closed operation side safety door is opened for a minute fixed range . A safety device for injection molding machines, which is equipped with interlocking pawls.