SU946759A1 - Method of cold forming of toothed sections to shape - Google Patents

Description

(5) METHOD OF COLD FORMING OF TEETH

PROFILE

one

The invention relates to the processing of metals by pressure and can be used in the manufacture of splined and gear profiles by plastic deformation.

Methods are known for forming gear profiles in which the workpiece is moved axially between the toothed rollers and rolled by them.

In the process of forming the toothed profiles, the main work of the plastic deformation is performed by the teeth of the tapered intake part of the toothed rolls of the PSD by the action of a continuously acting axial force to move the workpiece. In this case, in the zone of plastic deformation, large forces of contact friction arise that impede the flow of the metal formaem teeth.

These drawbacks are due to the fact that the specific pressures on the contact surface of the gear

The rolls and, accordingly, the deformations over the section of the profile are distributed extremely unevenly, which adversely reflects on the durability of the toothed rolls. To obtain the necessary surface cleanliness and the normal course of the shaping process, it is necessary to have the surface of the part to be preformed

, Q Phosphate with a coating, or use expensive and scarce molybdenum disulfide-based lubricants.

Closest to the proposed

15 is a method of cold shaping gear profiles, followed by rotating the workpiece with toothed rollers with simultaneous axial relative movement

20 blanks and rolls with the message for cooking oscillating movements. In the ultrasonic frequency range of 185 kHz with an amplitude of oscillatory displacements of 15–20 µmХ21. The disadvantages of this method are the insufficient efficiency of applying ultrasonic frequency oscillations when rolling teeth and slots with a mm module because of the insufficient power of ultrasonic generators used, the low energy transfer efficiency for creating vibrations, as well as the complexity and complexity of ultrasonic vibrocomplexes and the particular difficulty of applying ultrasonic vibrations. vibrations to the required part of the workpiece, which negatively affects the quality of the profiles, the lack of universality in the knurling of gear profiles. Parts with different configurations. The purpose of the invention is to expand the range of products being treated and to improve the quality of products. The goal is achieved by the fact that in the method of cold forming toothed profiles, in which the rotating workpiece is rolled by toothed rollers, with simultaneous axial relative movement of the workpiece and the rolls with message to the workpiece of oscillating movements, the oscillating movements of the workpiece are performed in the low frequency range from 5 to 50 Hz with amplitude vibrational displacement of 0.1-0.8 Mm. The drawing shows the implementation of the proposed method. The method is carried out as follows. The workpiece 1 is installed in centers 2 and 3 of the centering heads k and 5 of the carriage b, which then under the action of the hydraulic actuator 7 axially moves the workpiece 1 between the toothed rollers 8. Simultaneously with the hydraulic actuator 7, the pulsating vibrations, including the hydraulic cylinder 9, pulsator, operate 10 and pulsator drive 11. The pulsating force of the rod 12 of the hydraulic cylinder 9 is transmitted to the center 3 and the workpiece 1 rigidly mounted to it. Accordingly, the spring 13, pressing the center 2 in each period of the force unloading of the rod 12, ensures the separation of the contacting surfaces of the teeth of the nine rollers and the workpiece 1, which repeats in the process of forming with the pulsation frequency of the stem 12. To ensure a guaranteed separation of the contacting surfaces, the following condition is neo (): 5 LAf, where S is the speed of axial movement of the workpiece; stock ripple amplitude, stock ripple frequency. The optimum mode of pulsation is determined by the critical rate of deformation of the metal of the workpiece and depends on the degree of deformation, the mechanical properties of the material of the workpiece, the module of the toothed gear profile. The method is carried out as follows. Example 1. When rolling a spline profile with a module of mm, with a speed of axial movement of the workpiece, 6 mm / s at the number of revolutions of the workpiece / min, the axial force of rolling is 680 kgf. When rolling the same billet with the imposition of an additional pulsed axial feed with an amplitude of 25 mm and a frequency of f 15 Hz, the axial rolling force is 510 kgf, i.e. 25% less. Example 2. When rolling a spline profile module, 5 mm, with a speed of axial movement of the workpiece, 8 mm / s when the number of revolutions of the workpiece rpm, the axial force of the rolling is 1100 kgf. When rolling this workpiece with the imposition of an additional pulsating axial feed with an amplitude of 2 mm and a frequency of Hz, the axial force of the rolling is 800 kgf, i.e. 27% less. In order to avoid re-knuckling of the surface of the teeth of the rolling pro, experimental adjustment of the pulsation parameters A f is necessary when processing the program of the particular part. The values of the axial effort of rolling Q at various amplitude values are given in Table.

Claims (1)

Claim The method of cold forming gear profiles, in which a rotating workpiece is run 946759 * with gear rolls, with simultaneous axial relative movement of the workpiece and rolls with a message to the workpiece oscillating movements, characterized in that, in order to expand the range of processed products and improve product quality, oscillating movement of the workpiece is carried out in a low frequency range from 5 Hz to 50 Hz with an amplitude of vibrational displacements of 0.1-0.8 mm