JPH0454571B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a drive device for a nozzle touch in an injection molding machine.

Prior Art A drive device for nozzle touch of an injection device in a conventional injection molding machine uses a hydraulic cylinder to move the injection device, and a proximity switch is provided to detect the position of the injection nozzle. In addition, since the hydraulic cylinder is used, a hydraulic pump valve and the like are required, making the structure complicated.

Furthermore, a nozzle touch drive device using a servo motor is also known from Japanese Patent Laid-Open No. 179630/1983. However, in the device described in this publication, the output of one servo motor is switched by a clutch and used for driving mold clamping, injection, and nozzle touch.
A sensor is required to detect the nozzle touch position and the retracted position of the injection device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a nozzle touch drive device that does not use hydraulic pressure and has a simple configuration.

Structure of the Invention The present invention provides a nozzle touch drive device in an injection device of an injection molding machine, in which the drive device is composed of a servo motor for driving the injection device equipped with a position detector, and the rotation of the servo motor is converted into linear motion. The nozzle touch driving device is equipped with a transmission device for converting and moving the injection device, and detects the position of the nozzle touch using the position detector to stop and hold the rotation of the servo motor.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

In FIG. 1, reference numeral 1 denotes an injection device, which integrally has a cylinder 2 for injection, and a hopper 3 connected to the upper part of the cylinder 2 for supplying molding material into the cylinder 2. , a heater 4 is provided outside the cylinder 2 to directly heat the molding material.
is provided. A nozzle 5 for injecting molten molding material is provided at the tip of the cylinder 2, and a moving nut 6 is integrally provided at the bottom. Reference numeral 7 denotes an injection servo motor provided on one side of the injection device 1, and a detector 8 is integrally provided. 9 is the machine base, and there is a mounting base 1 on the top.
A rail 11 is integrally provided on the upper part of the mounting base 10, and the injection device 1 is movably mounted on the rail 11. 12 is a ball screw that is a male thread that is screwed into the nut 6;
Support stand 1 with screw shaft 12a at one end attached to machine stand 9
3, and a screw shaft 12 at the other end.
b is pivotally supported by a support plate 14 provided on one side of the machine base 9, and a gear case 15 is mounted on the support plate 14.
A servo motor 17 is provided which integrally has a detector 16 that detects the position via the servo motor 17 . Inside the gear case 15, the servo motor 17 is installed.
A driving gear 18 integrated with the motor shaft 17a of the servo motor 1 meshes with a transmission gear 19 integrated with the screw shaft 12b of the ball screw 12.
7 causes the transmission gear 19 to rotate via the drive gear 18 in the gear case 15,
The ball screw 12 rotates. Reference numeral 20 denotes a fixed plate, on which a mold 21 is integrally attached, and the mold 2
1 is provided with an injection port 22 of a nozzle 5.

Next, the effects of the embodiments of the present invention will be explained.

When the servo motor 17 operates, the transmission gear 19 integrated with the screw shaft 12b rotates via the drive gear 18 integrated with the motor shaft 17a of the servo motor 17, and the ball screw 12 integrated with the screw shaft 12b rotates. is rotated in the opposite direction to the right-hand thread, the nut 6 screwed into the ball screw 12 moves along the ball screw 12, and the injection device 1 integrated with the nut 6 is guided by the rail 11 as indicated by the arrow in the drawing. Move in direction A. At the same time as the nozzle 5 contacts the injection port 22 of the mold 21, the detector 16 detects its position, and the servo motor 17 stops and maintains that position.

Then, the injection servo motor 7 provided in the injection device 1 is operated, and the molten molding material in the cylinder 2 is injected from the nozzle 5 into the mold through the injection port 22 of the mold 21.

FIG. 2 and FIG. 3 show another embodiment of the present invention, and the injection device 1 is similar to the embodiment described above, and a pedestal 23 is integrally provided at the lower part, and both sides of the pedestal 23 are provided. There are guide rails 2 on both sides of the machine base 9.
4,24' are provided. Reference numeral 26 denotes a support provided at one end of the lower surface of the pedestal 23, and one ends of connecting arms 28, 28' are rotatably supported at both protruding ends by pins 27, 27', respectively. The other ends of the arms 28, 28' are connected to arm links 30, 3 by pins 29, 29', respectively.
The arm links 30, 30' are rotatably supported on one end of the arm link 0', and the other ends of the arm links 30, 30' are rotatably attached to both ends of a support 32 provided at one end of the machine base 9 by means of pins 31, 31'. It is pivoted.

Reference numeral 33 designates a ball screw having a male thread, and a pressing body 34 is provided at the tip of the pressing body 34. At the tip of the pressing body 34, one ends of arms 36, 36' are rotatably supported by pins 35, 35'. Arm 36,3
The other end of arm link 6' is rotatably supported by one end of arm link 30, 30' by pin 37, 37'. And these arm links 28, 28',
30, 30', arms 36, 36', and pressing body 34 constitute a toggle mechanism 25. Reference numeral 38 denotes a support plate attached to the sides of the fuselage 1 and the support body 32, and a gear case 39 is integrally attached thereto, and below the gear case 39, the position is detected as in the previous embodiment. A servo motor 17 having a detector 16 is provided, and a driving gear is provided in the gear case 39 integrally with a motor shaft (not shown) of the servo motor 17, and a nut, which is a shaft that is screwed into the ball screw 33, is provided. An integral transmission gear is provided to mesh with the drive gear.

In this embodiment, when the servo motor 17 operates, rotation is transmitted to a transmission gear having a nut via a drive gear (not shown) integrated with the motor shaft of the servo motor 17, and is screwed into the nut. When the ball screw 33 rotates in the right-handed screw direction, the pressing body 34 of the toggle mechanism provided at the tip of the ball screw 33 moves in the direction of arrow A in the drawing, and the toggle mechanism is activated.

That is, the arm links 30 and 30' rotate in the direction of the arrow B in the drawing about the shafts 31 and 31' through the arms 36 and 36' attached to the tip of the pressing body 34, so that the arm links 3
Connecting arm 28,2 attached to one end of 0,30'
8' pushes out the support 26 in the direction of arrow A in the drawing,
The sliding plate 25 of the pedestal 23 on which the injection device 1 is placed,
25' is guided by guide rails 24, 24'.
As soon as the nozzle 5 contacts the injection port 22 of the mold 21, the detector 16 detects this position, and the servo motor 17 stops and maintains that position.

Effects of the Invention As described above, the nozzle touch drive device of the present invention is driven by a servo motor dedicated to driving the injection device equipped with a position detector, so it has a simple configuration and can be driven by a servo motor. Since the position detector equipped to control the speed and position of the nozzle touch detects the detection of the nozzle touch, it is easy to detect the position of the nozzle touch, and the position control conventionally performed as servo motor control can be directly applied to the nozzle touch. Can be used for position control. In addition, there is no need for a special detector such as a limit switch to detect the nozzle touch, and the nozzle touch position can be controlled using only the servo circuit provided for the servo motor to control the speed and position of the conventional method. The configuration becomes very simple since there is no need for a control circuit that is required when the device is installed. Further, when the nozzle comes into contact with the mold, the current value of the servo motor changes, so the pressing force of the nozzle on the mold can be detected from the amount of change. Furthermore, the nozzle touch position can also be detected from the amount of change.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of an injection molding machine equipped with a device according to an embodiment of the present invention, and FIG. 2 is a partially cutaway front view of an injection molding machine equipped with a device according to another embodiment of the present invention. 3 are plan views of essential parts of the same device. 1... Injection device, 5... Nozzle, 6... Nut, 7... Servo motor, 8, 16... Detector,
9... Machine stand, 10... Mounting stand, 11... Rail, 12... Ball screw, 22... Injection port, 2
4, 24'...Guide rail, 25...Toggle mechanism.

Claims (1)

[Scope of Claims] 1. In a nozzle touch drive device in an injection device of an injection molding machine, the drive device is composed of a servo motor dedicated to driving the injection device equipped with a position detector, and the rotation of the servo motor is converted into linear motion. A drive device for a nozzle touch, comprising a transmission device for converting and moving the injection device, the position detector detects the position of the nozzle touch, and the rotation of the servo motor is stopped and held. 2. The nozzle touch drive device according to claim 1, wherein the transmission device has a toggle mechanism.