RU2596534C2 - Composite face grinding wheel - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention can be used in making precast end abrasive wheels for treatment of metals. Abrasive wheel comprises a body with intermittent coarse-grained abrasive layer, centering mandrel and installed coaxially to housing with possibility of axial movement of barrel with its end surface of continuous fine-grained abrasive layer. Centering mandrel and sleeve with fine-grained abrasive layer form a screw pair fitted with provision of axial movement of sleeve with fixation in working and idle positions stop screws with their thrust into inner surface of housing and creation of tension in thread of screw pair.

EFFECT: simple design and efficient roughing, finishing and finishing treatment of parts of machines and instruments.

1 cl, 3 dwg

Description

The invention relates to tools for metal processing and can be used at enterprises of the metalworking industry for effective roughing, finishing and finishing processing of workpieces of machine parts and devices.

Known prefabricated mechanical grinding wheels, consisting of a metal casing and abrasive elements attached to it in one way or another (SU, copyright certificates No. 971640, class B24D 7/00, 1982; No. 1002142, class B24D 7/06, 1983; No. 1100076, class B24D 7/00, 1984; No. 1100077, class B24D 7/00, 1984; No. 1102667, class B24D 7/00, 1984; No. 127737, class B24D 7/00, 1986; No. 1235709, class B24D 7/06, 1986; No. 1315273, class B24D 7/00, 1987).

Advantages are:

- the rational use of abrasive materials through the use of a metal body for repeated use and replaceable abrasive elements;

- the ability to reduce the heat stress of grinding workpieces with a discontinuous abrasive surface.

The reason that impedes the achievement of the technical result indicated below is the constancy of the characteristics of abrasive elements, which limits the use of one and the same circle for processing workpieces of parts from materials with different properties and different quality requirements for the processed surfaces.

Known prefabricated end abrasive wheel (SU, copyright certificate No. 1281393, class B24D 7/06, 1987), consisting of a metal body and abrasive segments made in the form of truncated sectors and fixedly mounted on the body using a flange.

The advantage of such a circle is similar to those described above.

The reason that impedes the achievement of the above technical result is the inability to change the relative position of the abrasive segments, which, as in previous cases, reduces the efficiency of using such circles in the conditions of multinomenclature production.

Known end abrasive wheel (SU, patent No. 2205742, class. B24D 7/14, 2003), having a housing with a coarse-grained abrasive layer attached to it for preliminary grinding, mounted coaxially with the body with the possibility of axial movement of a glass carrying fine-grained abrasive layers for the final grinding and the mechanism for extending the glass, which includes a plate element made of an alloy with thermomechanical memory and triggered when a circle of heated air is supplied through the channels in the housing.

The reasons that impede the achievement of the technical result indicated below include the fact that when using the specified circle, the abrasive layers used for final grinding form an intermittent working surface, which leads to additional oscillations in the technological system during grinding and to a deterioration in the microgeometry of the polished surfaces formed on the final stage of machining with an end circle.

The closest device of the same purpose to the claimed invention in terms of features is an end abrasive wheel having a discontinuous working abrasive surface for preliminary grinding and a continuous working abrasive surface for final grinding (RU Patent No. 2214901, class B24D 7/14, 2001), adopted as a prototype.

The reasons that impede the achievement of the technical result indicated below when using the known device adopted for the prototype include the fact that the specified circle has a rather complicated structure that complicates its manufacture, as well as the need to modernize the machine to provide a discrete supply of heated and cooled air.

The invention consists in the following. In order to simplify the design of the circle, the movement mechanism of the cup installed coaxially with the body of the cup, carrying a fine-grained abrasive layer, is made in the form of a screw pair formed by a cup and a centering mandrel and designed to extend the cup in the axial direction at the final grinding stage.

The technical result consists in simplifying the design of the circle.

The specified technical result during the implementation of the invention is achieved by the fact that, as in the known device, the end abrasive wheel comprises a body with an intermittent coarse-grained layer fixed on it, mounted coaxially with the body with the possibility of axial movement of the glass with a continuous fine-grained abrasive layer fixed on its end surface, and mechanism for moving the glass. The peculiarity lies in the fact that the mechanism for moving the glass is made in the form of a screw pair formed by the glass and a centering mandrel and fixed in the working and non-working position by the locking screws.

The drawings show: in FIG. 1 is a longitudinal section of an end abrasive wheel; in FIG. 2 is a bottom view of the circle of FIG. one; in FIG. 3 is a longitudinal section of a circle with an extended glass carrying a fine-grained abrasive layer.

The assembled end circle contains a metal body 1 (Fig. 1), a cup 2 coaxial with the body, a centering mandrel 3 and screws 4.

On the annular end surface of the housing 1, coarse-grained abrasive layers 5 are fixedly fixed (Fig. 2), and on the annular end surface of the glass, the fine-grained abrasive layer 6 is fixedly fixed.

Prefabricated end abrasive wheel is used as follows.

When removing the main allowance (for pre-treatment) grinding is carried out by coarse-grained abrasive layers 5, fixedly mounted on the annular end surface of the circle 1 body (Fig. 1) in the modes corresponding to preliminary grinding. The discontinuity of the working surface at this stage of grinding helps to reduce the heat stress of the pretreatment process and the formation of favorable physical and mechanical characteristics of the surface layers of the machined parts, while the working surface of the fine-grained layer is “recessed”, i.e. is at a certain distance H ₁ (Fig. 1) from the working surface of the coarse-grained layer and does not touch the workpiece surface.

After removing the main part of the allowance, the machine is stopped, the screws 4 are released (Fig. 1), and by turning the cup 2 relative to the centering fixed threaded surface of the mandrel 4, it is moved in the axial direction so that the fine-grained abrasive layer protrudes beyond the coarse-grained by an amount of H ₂ (Fig. . 3). The screws 4 are turned all the way into the inner end surface of the housing, while creating an interference fit in the thread of the screw pair, which prevents the glass from turning unintentionally. The machine is turned on and the rest of the allowance is removed with a fine-grained abrasive layer in the modes corresponding to the final grinding.

The continuity of the working abrasive surface at this stage of grinding helps to reduce vibration in the technological system and improve the microgeometry of polished surfaces.

After the grinding cycle is completed, the screws 4 “sweep”, turning the cup 2 returns it to its original (inoperative) position and is again locked with screws 4 (Fig. 1).

The axial (mortise) feed of the abrasive wheel during processing with both coarse and fine-grained abrasive layers is carried out from the feed drive of the grinding machine.

The application of the proposed wheel allows for one operation to perform with high quality preliminary and final grinding with the end face of the wheel for one set of blanks. At the same time, the design of the prefabricated end abrasive wheel is quite technologically advanced and does not require modernization of the spindle unit of the grinding machine for supplying heated or cooled air.

Claims (1)

A prefabricated end abrasive wheel, comprising a body with an intermittent coarse-grained abrasive layer fixed to it, a centering mandrel and axially mounted coaxially with the body with the body axially displaceable, a glass with a continuous fine-grained abrasive layer fixed on its end surface, characterized in that the centering mandrel and the glass are fine-grained layer form a screw pair, made to ensure axial movement of the glass with fixing in working and non-working positions with locking screws with focusing them on the inner surface of the housing and creating an interference fit in the thread of the screw pair.

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