SU1669694A1 - Grinding spindle - Google Patents

Abstract

The invention relates to a machine tool industry and can be used for sharpening carbide pins of drill bits. The aim of the invention is to expand the technological capabilities of the grinding spindle by providing double-sided axial movement of the grinding wheel during overload. The spindle includes a housing 1, in which a hollow shaft 4 and a stem 6 are located, on the square end of which a grinding wheel 7 is mounted, pressed against a faceplate 8. A shank 10 is coaxially with the stem 6, which interacts like a rod 6 with a torsion spring 11. The flywheel 12 The rod 6 is located in the hollow rod, which consists of a thrust part 16, kinematically connected with the rod 6, a torsion spring 18 and a sliding part 19 interacting with a hollow shaft 4. When an axial overload occurs, the grinding wheel 7 is braked accordingly, the rod 6. The flywheel 12, while retaining its inertia, by means of the shank 10 spins the spring 11, while a part of the energy is transferred to the thrust part of the hollow rod, which in turn leads to the unwinding of the spring 18. The spring 11, unwinding, lengthens the rod 6 is moved to the right, forming a gap between the grinding wheel 7 and the faceplate 8. Twisting the spring 18 will move the sliding part of the hollow rod to the left, which will provide a gap between it and the grinding wheel. These gaps allow the excess alternating axial load on the grinding wheel to be removed. 3 il.

Description

The invention relates to a machine tool industry and can be used when sharpening carbide pins drill bits "

The purpose of the invention is to expand the technological capabilities of the grinding spindle by providing double-sided axial movement of the grinding wheel during overload.

Fig „1 shows the spindle in the process of sharpening the carbide pin of the drill bit, general view; Fig. 2 shows the position of the grinding wheel at the moment of the excessive load P; in FIG. 3, the displacement of the grinding wheel by the size of the gap 1 “

The spindle includes a housing 1, closed by end caps 2 with a labyrinth seal, in which a hollow shaft 4 "is located on bearings 3

Washers 5 are screwed onto the shaft 4 with a labyrinth seal, which interact with the end caps 2 "

In the cavity of the shaft 4 there is a rod 6, on the square end of which there is a grinding wheel 7, which has a reciprocal square hole “

The grinding wheel is pressed against the faceplate 8, screwed onto the rod 6 and fixed with a lock nut

A shank 10 is located coaxially with the rod 6, between which there is a torsion spring 11, made of a single billet with a shank 10 and a rod 6 "

The flywheel 12 is screwed onto the shank, fixed by a lock nut 13.

The shank 10 is secured against axial movement to the left by sliding bearing 14 and a cover of 15 "

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The rod 6 is located in the hollow rod, which consists of a stop part 16 abutting on the bearing 14 and interacting with the rod by means of a spline joint 17, a torsion spring 18 and a sliding part 19 interacting with a hollow shaft 4 by means of a splined joint 200

The stop part 16 is made of a single tubular billet with a torsion spring 18 and a sliding part 19, the spring having a left wound, and the sliding part 19 is installed with the possibility of interaction with the grinding wheel 70

The housing 1 is fixed to the quill 21, which is spring-loaded by the spring 22 and has the possibility of reciprocating movement along the guide 23 from the force applied to the handle 240.,

The spindle is driven from an electric motor 25 mounted on the axis of the drive pulley 26, the belt drive 27 and the driven pulley 28 fixed on the hollow shaft 4 of the spindle

The spindle works as follows.

Before the beginning of sharpening, a centering is performed, which consists in aligning the axis 29 of the carbide pin 30 s. the vertical axis 31 of the grinding wheel 7 and the fastening of the crown 32 on the turntable 33 using a clamping device 34 "

Using the handle 24, the spindle moves down along the guides 23 until the grinding wheel 7 touches the carbide pulley 26, which rotates with the drill bit 32

on rotary table 33 (rotary table rotating speed 10-30 rpm)

The carbide pin 30, rotating a relatively fast-rotating grinding wheel 7 (14000 rpm), grinds, acquires a configuration that responds to the configuration of the seat of the grinding wheel 7 "

In the event that the axis 29 of the carbide pin does not coincide with the vertical axis 31 of the grinding wheel 7, an excessive load P on the wheel 7 occurs (indicated by an arrow) and the hollow shaft 4 brakes „

The flywheel 12, while retaining its inertia, begins to unwind the spring 11 by the shank 10, while a part of the growing motion is transmitted by the spline joint 17 to the stop part. 16 of the hollow rod and the additional spring 18 "begins to unwind also

The spring 11, unwinding, lengthens and affects the rod 6, which, together with the faceplate 8, moves to the right (indicated by the arrow) and forms a gap 1, allowing the grinding wheel to move to the right to the right (shown by dotted lines) „

In turn, the spring 18, taken into the part of the rotational movement of the flywheel by means of the stop part 16 with the spline connection 17, begins to twist and shorten, while the sliding part 19c with the external splines 20 is drawn into the hollow shaft and forms a gap 1 allowing grinding the displacement circle on the rod to the left (FIG. 3)

The axial reactive force from the unwinding of the springs 11 and 18 is absorbed by the sliding bearing 14 and the cover 15 "

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Under the action of excess load P, the grinding wheel moves to the right to the top of the gap 1 (Fig. 2), while the axis 31 of the grinding wheel 7 approaches the axis 29 of the carbide pin 30, as a result, the grinding allowance decreases and the excess load P is removed

When rotating the pin 30 on the 180s, an excessive force P appears, which acts on the grinding wheel in the opposite direction from the force P, while the gap 1 allows the grinding wheel to move to the left (shown by dotted lines) and remove the excess force P ().

The use of the proposed grinding spindle allows you to expand the technological capabilities of grinding due to a wider use of the range of grinding wheels (tips), as well as reduce the consumption of diamond grinding wheels, 5 protecting them from overload caused by inaccurate centering of the spindle created by the operator,

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chipped hard alloy and t "Do, as well as improve the quality of sharpening, eliminating the formation of microcracks on the pin and zadirov Formula

the invention

Grinding spindle according to aut. No. 1565663, characterized in that, in order to expand technological capabilities, it is provided with a hollow rod made of two coaxial parts interconnected by means of an additional torsion spring, one of the coaxial parts being kinematically connected with the rod, a. friend - with a hollow shaft.

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29

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FIG. 2

Claims (1)

Claim Auto spindle grinding spindle No. 1565663, characterized in that, in order to expand technological capabilities, it is equipped with a hollow stem made of two coaxial parts interconnected by means of an additional torsion spring, one of the coaxial parts being kinematically connected to the rod and the other to the polish shaft .