RU2571246C1 - Apparatus for inputting ultrasonic vibrations during thread cutting - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: apparatus comprises a vibration source and a waveguide. The waveguide is in the form of a flexible coiled steel metal hose which is densely filled with a line of ceramic spheres with craters, wherein the waveguide is rigidly connected by one end to the vibration source, and the free end of the waveguide is linked to a forked clamp for mounting a workpiece. The apparatus may be provided with a pusher which is mounted on the free end of the waveguide, and the spheres of the waveguide may have a variable diameter and crater depth, which increase towards the vibration source.

EFFECT: broader functional capabilities and high mobility of the apparatus owing to independence of the system for inputting ultrasonic vibrations from the workpiece and the cutting tap.

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Description

The invention relates to mechanical engineering and is intended to improve the efficiency of tapping with the use of energy of ultrasonic vibrations.

A device is known for applying ultrasonic vibrations to a tap, comprising a source of oscillations and a rigid angular waveguide in contact with the side surface of the tap through a fork tip. The waveguide is located perpendicular to the cutting edge of the tap (see RF patent No. 2252843, IPC B23G 1/16, publ. 05.27.2005).

The disadvantages of this device include the following:

1. Standard machine taps have a very gentle angle of the cutting edge, in the range of 6-12.5 °, which implies an almost perpendicular arrangement of the waveguide to the tap. Since the device is claimed for small-sized threads, pressing such a waveguide for acoustic contact will cause the axis of the tap to bend and skew in the hole;

2. The device will not provide reliable acoustic contact, because at the end of the cutting, the forked tip no longer contacts the feathers of the tap, but switches to its smooth part, and the meaning in its angular arrangement is lost. In addition, pressing the fork tip to the feathers of the tap entails rapid wear.

It is also known a device for supplying ultrasonic vibrations to a body part containing a vibration source and a rigid waveguide (see RF patent No. 2290282, IPC B23G 1/16, publ. 12/27/2006).

The capabilities of such a device are limited by the mass of the workpiece, and also by the fact that the waveguide does not provide a strict directivity of ultrasonic vibrations to the area of thread formation. With dimensional workpieces, the vibrational energy will be dissipated in the material, and only an insignificant part of it will fall into the threading zone. The waveguide design does not allow you to direct the oscillations along the axis of the hole, because a significant part of the energy will be spent on shear microstrains between his paw and the mounting plane of the workpiece. The device does not allow to supply oscillations to a group of holes, because it does not provide for the possibility of positioning the waveguide. In addition, the location of the oscillation source and the waveguide together with the workpiece clutters the working space of the machine.

The technical result of the proposed device is to expand the functionality and increase the mobility of the device by creating independent from the workpiece system for supplying ultrasonic vibrations.

The result is achieved in that the device for feeding ultrasonic vibrations when threading, containing an oscillation source and a waveguide, is characterized in that the waveguide is made in the form of a flexible steel twisted metal sleeve tightly filled with a number of ceramic balls with holes, while the waveguide is rigidly connected to the source at one end oscillations, and the free end of the waveguide is equipped with a fork tack to secure the workpiece.

The device is also characterized in that it can be equipped with a pusher mounted on the free end of the waveguide.

The device also differs in that the balls of the waveguide can be made with variable diameter and depth of the hole, with an increase in the direction of the oscillation source.

The flexibility of the waveguide is based on the use of ceramic balls with holes in it. The hole of the balls provide a rigid axial fixation of the waveguide line and eliminate lateral extrusion of the balls. Ceramics, unlike steel, exclude setting and welding of the material when exposed to ultrasonic vibrations.

Unlike the prototype, the use of a flexible waveguide makes it possible to increase the mobility of the ultrasound system and make it independent of the elements of the working area of the machine and the structural parameters of the part. The presence of flange elements for attaching the ends of the waveguide provides axial compression of the balls and reliable acoustic coupling of a stationary oscillation source with movable elements for their supply in conjunction with the parts for securing the workpiece. Other options are possible when the oscillation source is movable and the supply element is fixed, or when both of them move at different speeds or at different distances.

The flexible design of the waveguide expands the functionality of the device, since it allows you to implement any scheme for supplying acoustic energy to the area of thread formation relative to the hole: from above, from the side, from below, etc. The prototype does not have such capabilities.

Unlike the prototype, a flexible ball waveguide is versatile due to the fact that it can be easily replaced by another structural type, for example, a waveguide with a different length or other transverse size, or a waveguide — an oscillation velocity amplifier (concentrator) containing balls with a diameter increasing towards the source of oscillations.

The efficiency of the supply of acoustic energy can be increased if the drive part of the clamping elements of the part is separated from the waveguide part by vibration isolating pads, for example textolite or lead.

In FIG. 1 shows a device for supplying ultrasonic vibrations when threading. It contains a tap 1, a workpiece with a hole 2, which is clamped and released by a fork stick 3 using a rod 4, a pneumatic cylinder 5 and a spring 6. To increase the ultrasound concentration and eliminate spurious energy dissipation, the stick with its back side rests on the support base through a vibration-isolating gasket 7.

Ultrasonic vibrations are transmitted to the workpiece 2 through the tack 3 from the flexible waveguide in the form of a twisted metal sleeve 8 filled with ceramic balls 9 with holes, while the balls are pressed against each other through their holes between the oscillation source 10 and the tack by means of union nuts 11, welded terminals 12 and flange mounts 13.

In FIG. Figure 2 shows a variant of a flexible waveguide acting as a vibration concentrator or oscillation velocity amplifier. The metal sleeve 8 is filled with ceramic balls 9 with holes, while the balls are compressed into their holes by welded terminals 12 through end stops. The terminals have union nuts 11 for fastening the metal hose.

The balls have a diameter increasing towards the source of oscillation.

In FIG. 3 and 4 show other possible schemes for supplying ultrasonic vibrations. In FIG. Figure 3 shows the option of supplying vibrations to the hole on the side. In this case, the clamping plunger 14, carrying the waveguide 8, after positioning the workpiece is brought to its lateral surface so that the angular aperture of the oscillations α would overlap the main part of the forming hole.

In FIG. 4 shows the case of supplying vibrations to the edge of the workpiece. For this, an angular pusher 14 with a waveguide 8 is used, and the vibration aperture should also cover the entire depth of the hole.

The operation of the device is as follows. Before threading, tap 1 is at the top, and workpiece 2 is freed from fork tack 3, because the rod 4 and the piston of the pneumatic cylinder 5 are in the upper position and the tack is raised by the spring 6. The lower part of the waveguide 8 is also lifted along with the tack, while the oscillation source 10 is stationary. The workpiece is positioned in a new position by the machine table for threading in the next hole. After stopping the table and the workpiece, the pneumatic cylinder 5 is activated, and the workpiece 2 is clamped with a fork tack 3 with the back of its support on the vibration-isolating gasket 7. The lower part of the waveguide 8 with balls 9 also lowers along with the tack, because connected to it by terminal 12, union nut 11 and flange fastening 13. After clamping the workpiece, the oscillation source 10 is turned on, tap 1 goes down and cuts the hole.

The proposed technical solution extends the functionality of the device, makes it more mobile relative to the elements of the working area of the machine and increases the structural versatility of the device.

Claims (3)

1. A device for supplying ultrasonic vibrations when threading a workpiece, containing an oscillation source and a waveguide, characterized in that the waveguide is made in the form of a flexible steel twisted metal sleeve tightly filled with a number of ceramic balls with holes, with one end of the waveguide rigidly connected to the oscillation source and the free end of the waveguide is connected to a fork tack designed to secure the workpiece. 2. The device according to p. 1, characterized in that it is equipped with a pusher mounted on the free end of the waveguide. 3. The device according to p. 1 or 2, characterized in that the balls of the waveguide are made with a variable diameter and depth of the hole, with an increase in the direction of the oscillation source.

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