SU1599241A1 - Apparatus for thermal resistance welding of thermoplastic materials - Google Patents

Abstract

The invention relates to the welding of plastics and can be used in contact thermal flash welding, cutting and cutting - welding of film and sheet thermoplastic materials. The goal is to improve the quality of the welded joint and the performance of the device. For this, the device is equipped with an acoustic welding head mounted on the frame with the possibility of longitudinal movement and a spring-loaded vibrator connected to the welding table. With the working end of the acoustic welding head through a puller of ultrasonic vibrations connected to one end of the electric heating elements. The second end of the electric heating elements is connected to the vibrator. Electric heating elements are installed parallel to the axis of the acoustic welding head. Electric heating elements are made of a length that is a multiple of a half-wave of ultrasonic vibrations, and their minimum length is equal to the wavelength of ultrasonic vibrations. 4 il.

Description

The invention relates to a technique for welding plastics and can be used for cutting-welding of film and sheet thermo-thermal materials.

The purpose of the invention is to increase the quality of the welded joint and device performance,

FIG. 1 shows a device, a longitudinal section;: FIG. 2 — view along arrow A; FIG. on fig.Z - view along arrow B on fig, 4 - section bb In fig, 1.

The device for thermocontact welding of thermoplastics contains a frame 1 on which a support is mounted

2 with acoustic welding head 3 including a water tank 4, converter 5, transformer 6 of elastic oscillations and waveguide 7 Welding head 3 is insulated from the base 1 a. The support 2 is mounted on the base 1 with the possibility of movement with the help of a screw gear 8 "Acoustic welding head 3 is fixed on the caliper 3 with the help of angle 9 and bolts 10 and 11,

At the working end of the waveguide 7, a puller 12 of ultrasonic vibrations is fixed, in particular, attached to which the upper end of the electric heating elements 13 is attached,

made in the form of metal wire or tapeNo. The upper end of the electric heating elements 13 can be connected to the stripper 12 by means of a threaded joint 14 or soldered to it. The lower end of the electric heating elements 13 is connected, for example, by a threaded connection

With a vibrator 15 installed on the guides 16 and spring-loaded relative to the welding table I7 using springs 18o, the vibrator 15 is insulated from the guides of the insulation material. Electric heaters 1–3 can be installed one or several in a row on some the distance from the axis of the welding head is parallel to it,

Electric heating elements 13 are made to be a multiple of the half-wave of ultrasonic vibrations, their t-atkmal length being equal to the wavelength. The fixed arrangement of the welding table 17 and the vibrator 15 corresponds to the propagation wavelength points of the electric heating elements 13 oscillating with maximum resonance. frequency and amplitude offset

The device also contains a power supply 19, a ballast resistance 20 for controlling the magnitude. welding current, ammeter 21, voltmeter 22 to monitor the welding process and material feed mechanism (not shown) о The device is mounted on a 23 ° base

The device works as follows

Before entering the power source of the electric heating elements and the ultrasonic generator, it is necessary to screw the electric heating elements 13 by means of a screw gear 8 of the support 2 by means of a spring-loaded vibrator 15 with a force of 10-25 kg, fixing the welding table 17 and the vibrator 15 at the point corresponding to the half-wave resonant and then include water cooling of the acoustic head 3 and the power supply source 19 of the electric heating welding elements 13

The process of welding and cutting-welding is that when an electric heating welding element 13 comes into contact with thermoplastic 24 V

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no contact through the abc line the thermoplastic enters the flowing state, and in the tail part along the adc line its glass transition occurs (Fig. A) to obtain stable and stable processes of melting, spreading the molten thermoplastic, treating the width of the cut, glass transition and forming a weld seam The combined introduction of ultrasonic vibrations into the welding zone and vibration into the thermoplastic to be welded or cut by turning on the ultrasonic generator, as a result of which the welded material 24 into the melting zone abc lines and the glass transition zone along the adc line of the weld 25 by means of electric heating welding elements 13 are introduced longitudinal, transverse and bending (when the welding elements are not coaxial with the waveguide 7) mechanical vibrations of the ultrasonic frequency, which are amplified by removing 12 ultrasonic vibrations Weldable thermoplastic additionally subjected to mechanical longitudinal (vertical) oscillations (vibrations) with the oscillation frequency and the amplitude of the vertical displacement + A (figoO equal to the oscillation frequency and the amplitude And the displacement of the lower end of the electric heating welding element 13, by which it is elastically interconnected with the vibrator 15 by means of a threaded joint or soldering. The combined effect of ultrasonic frequency vibration on the melt and the vertical vibration of the thermoplastic to be welded accelerates the interdiffusion of the molecules of the welded parts and provides intensive movement of the melt

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Claims (1)

Invention Formula A device for thermocontact welding of thermoplastics, comprising a frame, electrical heating elements made in the form of wire, and a welding table, characterized in that, in order to improve the quality of the welded joint and the performance of the device, it is equipped with an acoustic welding head mounted on the frame with the possibility of longitudinal movement, one end of the electric heating elements connected to the welding table of the dummy is connected to the working end of which by means of the ultrasonic oscillation remover ennym vibrator, to which a second end of the electric heating elements, wherein electric heating elements set. parallel to the axis of the acoustic welding head and made a length that is a multiple of the half-wave of ultrasonic vibrations, and their minimum length is equal to the wave of ultrasonic vibrations. P77Fig .1 FIG. 2 Buss  12