JP3250611B2 - Tie bar extension measuring device for mold clamping mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tie bar extension measuring device for a mold clamping mechanism provided in an injection molding machine.

[0002]

2. Description of the Related Art As means for measuring the expansion and contraction of a tie bar,
A structure in which a reference rod is inserted into a tie bar and a detector is attached between the free end of the reference rod and the fixed platen is disclosed in Japanese Patent Publication No. 6-4 / 1994.
H.264.

[0003]

In this conventional structure, there is no particular problem in the measurement accuracy. However, since a long hole is formed in the center of the tie bar, it takes time and effort to process the tie bar. There is a problem that the cost is increased in manufacturing the fastening mechanism.

The present invention has been conceived in order to solve the above-mentioned problems of the conventional structure. The object of the present invention is to use a side surface of a tie bar for setting a reference bar, thereby simplifying the setting of a simple measuring device. By using a long groove to accommodate the reference bar, the processing of the tie bar becomes easier than in the case of the long hole, and a new tie bar elongation measuring device for the mold clamping mechanism that can reduce the manufacturing cost of the mold clamping mechanism. To provide.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a reference bar having a required length is provided along the axial direction on a side surface of a tie bar between a fixed plate and a pressure receiving plate of an injection molding machine. One end of the reference bar is fixedly fastened to the tie bar, and a terminal for detecting the extension of the tie bar is protruded from the opposite end.The measuring instrument is mounted on the inside of the detection terminal facing the tie bar pulling side. Alternatively, it is provided by a support bar fixed to the tie bar, and the measuring rod is brought into contact with the inner surface of the detection terminal.

In the above configuration, it is only necessary to fix the reference bar to the side surface of the tie bar along the axial direction and to provide a measuring instrument at the detection terminal on the opposite end side. The installation is easier than in the case where the reference rod is penetrated and the reference rod is inserted. Also, no special considerations are required in the production, and the setting of the reference bar is simple because it is only necessary to fix one end to the tie bar and set it as a fixed point.Since the measurement site is also external, the installation of the measuring instrument is troublesome. There is also a simplicity that the elongation amount of the tie bar can be accurately measured only by contacting the measuring device with the detection terminal without being hung.

[0007]

1 shows a toggle type mold clamping mechanism, wherein 1 is a fixed plate, 2 is a pressure receiving plate provided with a mold clamping cylinder 3, and both plates are located at positions opposed to a machine stand 4. It is erected.
Reference numerals 5 and 5 denote tie bars provided over both panels. Both ends of the tie bars are inserted and fixed to the four corners of both panels, and the movable plate 6 is movably inserted and supported by the tie bars 5 and 5. I have. The movable platen 6 and the pressure receiving platen 2 are connected by a toggle mechanism 7 having a normal structure operated by the mold clamping cylinder 3. The movable cylinder 6 is moved forward and backward and the mold is clamped by the operation of the piston rod 8 by the mold clamping cylinder 3. You can do it.

The fixed plate 1 and the pressure receiving plate 2 are moved on the machine base within a range in which the tie bars 5 and 5 can be extended during mold clamping. It is slidably erected on the exercise guide 9.

Reference numeral 10 denotes a fixed mold attached to the fixed platen 1;
Is a movable die attached to the movable platen 6, and the temperature of the die is adjusted in advance so as to be affected by the material temperature at the time of injection molding so that the thermal expansion does not change each time.

One (most preferably all) of the tie bars 5 and 5 is provided with a tie bar extension measuring device comprising a long reference bar 12, a detection terminal 13 and a measuring device 14.

The reference bar 12 is made of metal, ceramic, or the like. One end of the reference bar 12 is fastened and fixed to the fixed plate 1 side of the tie bar 5 with bolts or pins 15 so that the tie bar between the fixed plate 1 and the pressure receiving plate 2 is fixed. The detection terminal 13 is protruded outward at a right angle from the reference bar 12 at the opposite end located on the upper surface of the tie bar inside the pressure receiving plate of the reference bar 12. From the measuring terminal 14 to the detection terminal 13
Is provided so that the extension amount of the tie bar due to the mold clamping force can be measured.

The measuring instrument 14 uses a micro gauge, a digital micrometer, or the like as an instrument for measuring the amount of extension of the tie bar 5. The measuring instrument 14 includes a holder 14a fixed on the upper surface of the pressure receiving plate 2 and a reference bar 12 extending from the holder 14a. Is movably hung on a support bar 14b provided horizontally on the sensor so that the position can be arbitrarily changed, and the measuring rod 14c is placed on the inner surface of the detection terminal 13 inside the detection terminal 13 facing the tie bar pulling side. It is provided in contact with.

In the measuring device having the above configuration, although the reference bar 12 abuts on the side surface of the tie bar 5, it is omitted in the drawing, but the bush 16 of the movable platen 6 needs a guide groove for the reference bar 12. In the case where the reference bar 12 is accommodated in the tie bar and attached to the tie bar, such a guide means is not required.

For example, as shown in FIG. 2, a groove 17 having a required length is cut in the upper surface of the tie bar 5 in the axial direction.
7, the reference bar 12 which is slightly shorter is housed, one end is fixedly fixed to the tie bar 5 and the detection terminal 13 is protruded at the opposite end as in the case of FIG. Since the opposite end side of the reference bar 12 is in a free state, the reference bar 12 is not affected by the expansion and contraction of the tie bar 5 and always maintains a constant length.

The direction of the reference bar 12 is not limited to the direction shown in the figure. The fixing terminal may be positioned on the tie bar on the side of the pressure receiving platen 2 and the detection terminal 13 may be located on the fixed platen 1 side. Means that the measuring device 14 is set on the fixed platen 1.

The measurement of the amount of elongation of the tie bar 5 by the above measuring device is performed by setting the value of the measuring device 14 at this time as a reference value since the tie bar 5 does not elongate before clamping. The movable platen 6 moves forward by the extension of the piston rod 8 of the toggle mechanism 7, and the fixed mold 10 and the movable mold 11
Is closed, and when the fixing plate 1 receives the mold clamping force via the mold, the mold clamping force acts on the tie bar 5 as a tensile force. At this time, the tie bar 5 expands by losing the mold clamping force, and the elastic deformation recovery force of the tie bar 5 generates a mold clamping force proportional to the amount of elongation.

However, the reference bar 12 having one end fixed to the tie bar 5 is such that the fixing point due to the fixing moves only to the fixed platen side together with the tie bar 5 by the amount of extension, and no extension occurs there. Accordingly, the position of the detection terminal 13 at the opposite end is also displaced toward the fixed platen by the amount of movement of the fixed point, and the amount of displacement is measured by the measuring device 14 as the amount of extension of the tie bar 5. Also, when the tensile force on the tie bar 5 is removed with the mold opening and the tie bar 5 returns to its original length,
The fixed point of the reference bar 12 also returns to the position before the mold clamping, the detection terminal 13 also returns to the original position, and the value of the measuring device 14 becomes the original value. Therefore, each time the tie bar 5 extends, the amount of extension is automatically measured.

In the above embodiment, the measuring device 14 is installed on the pressure receiving platen 2. However, when the extending direction of the tie bar 5 occurs in the left-right direction in the figure, as shown in FIG. To tie bar 5 with band 18 and set screw 19
Or by using a well-known means such as a magnet, but in this case, it is possible to measure the elongation of the tie bar 5 only by changing the measurement area without changing the others. it can.

Although the above embodiment is directed to a tie bar of a toggle-type mold clamping mechanism, the tie-bar extension measuring device of the present invention is not directly related to the mold clamping means. The present invention is not limited to the toggle-type mold clamping mechanism as shown in the drawings, since the present invention can be adopted without any change, and can be adopted even if the drive system is an electric system other than the hydraulic system.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a main part of a mold clamping device provided with a tie bar extension measuring device according to the present invention.

FIG. 2 is a longitudinal sectional side view of a main part of a mold clamping device provided with a tie bar extension measuring device according to another embodiment of the present invention.

FIG. 3 is a partial view showing another installation state of the measuring instrument.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed board 2 Pressure receiving board 3 Mold clamping cylinder 5 Tie bar 7 Toggle mechanism 8 Piston rod 9 Machine base 12 Reference bar 13 Detecting terminal 14 Measuring instrument 15 Pin for fixing and fixing 16 Movable board bush 17 Long groove of reference bar 18 Measuring instrument mounting Band for

Claims (1)

(57) [Claims] 1. A reference bar having a required length is axially abutted on a side surface of a tie bar between a fixed plate and a pressure receiving plate provided in a mold clamping device of an injection molding machine, and one end of the reference bar is connected to a tie bar. At the opposite end, a terminal for detecting the extension of the tie bar is protruded, and a measuring instrument is provided by a support bar fixed to the panel body or the tie bar on the inside facing the tie bar pulling side of the detection terminal, A tie bar extension measuring device for a mold clamping device, wherein a measuring rod is in contact with an inner surface of a detection terminal.