RU185520U1 - PNEUMATIC HAMMER - Google Patents

Abstract

The utility model relates to mining and construction, in particular to pneumatic hammers.

Pneumatic jackhammer containing a handle fixed with the possibility of movement relative to the barrel, in which there is a central channel and openings for air passage, an intermediate link with an annular chamber formed by an internal bore, a valve, an air distribution mechanism, a hammer, made with the possibility of reciprocating movements and dividing the barrel into the chamber of the working and idle, a damping ring made of an elastic polymer material placed inside the cavity Handles, wherein provided in the form of a cylinder with a central hole and tapered toward the end portion of the intermediate member, wherein the hammer is covered with damping materials and nickel-fluoroplastic epoxy varnish.

The technical result of the utility model is to increase the reliability of the drummer and increase labor productivity.

Description

The utility model relates to mining and construction, in particular to pneumatic hammers.

Known pneumatic hammer containing sequentially placed a hollow handle, coaxially located in it and axially spring-loaded glass with axial cavities located in the last pistons, and a hollow body, an air distribution device, a hammer, dividing the cavity of the hollow body into working and idle chambers, axial cavities are made through to connect the chambers between the handle and the glass and between the glass and the body, and the pistons are plungers and are located in the axial cavities with POSSIBILITY axial movement. [one]

The disadvantages of this pneumatic hammer are the low reliability of the hammer and labor productivity.

The closest pneumatic jackhammer is known, comprising a handle fixed with a possibility of movement relative to the barrel, in which there is a central channel and openings for air passage, an intermediate link with an annular chamber formed by an internal bore, a valve, an air distribution mechanism, and a striker configured to provide a return - translational movements and dividing the barrel into the chamber of the working and idle, a damping ring made of an elastic polymer material, p zmeschennoe within the cavity of the handle, wherein provided in the form of a cylinder with a central hole and tapered toward the end portion of the intermediate member. [2]

The disadvantages of this pneumatic jackhammer are the low reliability of the striker and labor productivity.

The technical result of the utility model is to increase the reliability of the drummer and increase labor productivity.

The problem is solved in that in the proposed device, a pneumatic hammer, containing a handle fixed with the possibility of movement relative to the barrel, in which there is a central channel and holes for air passage, an intermediate link with an annular chamber formed by an internal bore, a valve, an air distribution mechanism, a hammer made with the possibility of providing reciprocating movements and dividing the barrel into the camera working and idling, a damping ring, made of elastomeric material, housed within the cavity of the handle and formed as a cylinder with a central hole and tapered toward the end portion of the intermediate member, wherein the hammer is formed with a damping nickel coating with a thickness of 50 microns.

The proposed technical solution allows to increase the reliability of the drummer and increase labor productivity due to changes in the overhaul period.

The loading of the projectile is shock-wave in nature, accompanied by noise and vibration, the destruction occurs during the interaction of rarefaction waves following the front of the shock waves. In the region of interaction of rarefaction waves, large short-term tensile stresses arise, leading to the destruction of the material. This specific type of dynamic fracture caused by the interaction of rarefaction waves is called spallation [3].

The sharp edges of the detached nose of the striker destroy the inner surface of the barrel, reduce compression, as a result of which the barrel becomes unrepairable [4].

A modern method of solving the noise and vibration problem is the use of a viscoelastic damping material, with which energy during vibrations can be absorbed inside some small element introduced into the structure [5].

It is known that ferromagnets are characterized by abnormally large internal friction, which is due to the magnetic structure of the material. An additional dissipation of energy is caused by losses during domain reorientation (the region of spontaneous magnetization) during oscillations [6]. This served as the basis for the choice of nickel as a ferrimagnetic material as a coating for the striker. Dissipation of vibrations caused by impacts of the striker against the peak, and, consequently, a decrease in their amplitude and a decrease in the destruction of the nose.

Given that the work of the projectile can be attributed to aggressive environments and with increased wear, then the optimal coating thickness of nickel will be 50 microns [7].

To apply a damping nickel coating with a thickness of 50 μm, the following electrolyte composition of a galvanic bath is used [5]:

- Nickel sulfate NiSO47H4Cl 35-45 g / l;

- ammonium chloride NH4Cl 35-45 g / l;

- boric acid H3BO3 30-40 g / l;

- pH 3.5-4.5;

- current density 2-5 A / d ² ;

- voltage at the terminals 2.5-3 V.

Updating the damping nickel coating is performed during the overhaul of the device.

The increase in labor productivity is achieved by reducing the wear of the piston part of the hammer, as these coatings have the combined antifriction property.

Information sources

1. Copyright certificate SU 1472244 A1, IPC B25D 17/24. Date of publication 04.15.1989. Bull. No. 14.

2. Patent RU 168881, IPC B25D 17/24 (2006.01). Published 02.22.2017 Bull. No. 6.

3. Novikov S.A. The destruction of materials under the influence of intense shock loads // Soros Educational Journal. - 1999. - No. 8. - from. 116-121.

4. Impactors for jackhammers and concrete breakers - causes of failure [Electronic resource]. URL: https://tradeacons.com/stati/udarniki-k-otboynym-molotkam-i-betonolomam-prichiny-polomki/

5. The Languageless V.F. Averyanov I.N. On the use of damping coatings to reduce vibration and sound attenuation in the repair industry // Bulletin of PNIPU. Aerospace Engineering. - 2014. - No. 38. - from. 49; from. 52-53.

6. Bozort R. Ferromagnetism. - Metallurgy, 1956. - 234 p.

7. Chemical coatings with metals and alloys [Electronic resource]. URL: http://delta-grup.ru/41/66.htm.

Claims (1)

Pneumatic jackhammer containing a handle fixed with the possibility of movement relative to the barrel, in which there is a central channel and holes for air passage, an intermediate link with an annular chamber formed by an internal bore, a valve, an air distribution mechanism, a hammer, made with the possibility of reciprocating motion and dividing the barrel into the chamber of the working and idle, a damping ring made of an elastic polymer material placed inside the cavity handles and made in the form of a cylinder with a Central hole and tapering towards the intermediate link end part, characterized in that the hammer is made with a damping nickel coating, the thickness of which is 50 μm.