RU2252841C1 - Boring bar - Google Patents

Abstract

FIELD: metal working, boring precise openings.

SUBSTANCE: boring bar includes housing divided by means of groove by rigid and movable portions, rough adjustment screw resting upon supporting surface. Cutting member is mounted in seat of movable portion. In order to enlarge range of bored diameters and to provide easy tuning by precise dimensions, boring bar includes additional screw with cone surface and movable portion has inclined surface engaging with cone surface. Additional screw may be mounted inside rough adjustment screw. Thread pitches of additional screw and rough-adjustment screw may be different by value or sign. Housing may have supporting surface for limiting movement of rough-adjustment screw. Additional screw may have stop surface engaging with movable portion. Boring bar may have one more screw for providing wide range of tuning.

EFFECT: enlarged range of bored diameters, simplified tuning by precise dimensions.

7 cl, 2 dwg

Description

The invention relates to the field of metalworking.

Known boring mandrels (AS USSR No. 532485, MKI V 23 V 29/03) containing an elastic holder and an additional elastic element made in the form of a spring, interacting with the elastic holder by means of a stop, the spring force being regulated by a screw.

The disadvantage of this technical solution is the low technological capabilities, consisting in a small range of processing diameters.

Also known is a boring tool (AS USSR No. 539693, MKI V 23 V 29/8, prototype), comprising a threaded insert with an elastic tool holder or holder, a tool deformation mechanism and a wedge moved along the axis interacting with an elastic tool deformation element.

The disadvantage of this technical solution is the impossibility of processing relatively small diameters and their narrow range of boring.

An object of the invention is to expand the range of the bored diameter and ease of adjustment of exact dimensions.

The problem is solved in that the boring mandrel, including the housing, which is divided by a groove into a rigid and elastic or movable part, a cutting element is attached to the socket of the movable part.

There is a coarse adjustment screw, which abuts against the supporting surface, deforming the elastic bridge of the moving part, as well as an additional fine adjustment screw with a conical surface, with which it interacts with the inclined surface made in the moving part.

An additional screw is installed inside the coarse screw.

The threads in the additional screw and the coarse screw are made different in size.

The threads in the additional screw and the coarse screw are made different in direction.

The housing contains a support surface for restricting the movement of the coarse adjustment screw.

The additional screw contains a thrust surface interacting with the movable part.

The boring bar additionally contains a screw to go into a wide range of settings.

The invention is illustrated by drawings, where figure 1 shows a boring mandrel, General view, a local section; figure 2 is a view of figure 1.

The boring mandrel consists of a shank 1 and a housing 2. The housing 2 is divided into two parts: elastic or movable 3 and rigid 4. The movable part 3 is formed with a groove 5 when the housing 2 is cut. As a result, an elastic jumper 6 of width “a” with the reference center "0" of rotation of the movable part 3 with the cutting element 7. The movable part 3 has an inclined surface 8 and a supporting surface 9 on the movable part 3. The supporting surface 9 is obtained by plating holes 10 at the initial position of the movable part 3. The supporting surface 11 is obtained In the same way, only on the rigid part 4 of the housing 2, in the maximum possible deformable (in which elasticity ends) position of the movable part 3. A thread 12 is made in the hole 10, with which the screw 13 is mated to the end cylindrical protrusion 14, which can interact with the surfaces 9 and 11. Moreover, the surface 11 serves as a limiter for the screw 13. An additional fine adjustment screw 15 with a conical surface 16 is installed inside the screw 13. The screw 13 is used for coarse adjustment, and the screw 15 is for fine adjustment. In accordance with this, they can have different thread steps both in magnitude and direction, and they work in their specific ranges for setting the boring mandrel to the diameter of the bore d _p + δd _p . Hole processing in high-speed and power cutting conditions requires significantly greater rigidity of the size adjustment mechanism than with a conventional one. To do this, in the head 17 of the screw 15 there is a thrust surface 18, which, when configured, interacts with the movable part 3. The transition to a different bore range Δd _p occurs due to the movement of the cutting element 7 by the screw 19 with the screw 20 released.

Setting the boring mandrel is as follows. First, by rotating the screw 19, the desired bore range d _p + Δd _{p is} selected, then the coarse adjustment screw 13 is rotated. Rough adjustment allows you to set a narrower range of changes in the diameter of the bore, which can overlap the fine adjustment. Then, turning the fine adjustment screw 15, which has a significantly low sensitivity, we finally adjust the boring bar to the required hole diameter.

Setting the boring mandrel in high-performance mode is carried out as follows: coarse - by rotating the screw 15, when the screw 13 is inhibited, and exact - vice versa, by rotating the screw 13 when the screw 15 is inhibited, due to the difference in the threads of the screws 13 and 15. As a result, friction is reduced, t .to. the thrust surface 18 of the screw 15 does not rotate, but only interacts with the moving part 3 in a smooth translational motion. The rigidity in the tuning mechanism automatically increases at this time.

Claims (7)

1. A boring mandrel, including a housing that is divided by a groove into a rigid and movable part, a cutting element is attached to the socket of the movable part, a screw for rough adjustment abutting against the supporting surface, characterized in that it contains an additional screw with a conical surface, and the movable part is made an inclined surface with which the conical surface interacts. 2. The boring mandrel according to claim 1, characterized in that the additional screw is installed inside the coarse screw. 3. The boring mandrel according to claim 1, characterized in that the steps of the threads in the additional screw and the rough adjustment screw are made different in magnitude. 4. The boring mandrel according to claim 1, characterized in that the threads in the additional screw and the rough screw are made different in direction. 5. The boring mandrel according to claim 1, characterized in that the housing contains a supporting surface to limit the movement of the screw rough settings. 6. The boring mandrel according to claim 1, characterized in that the additional screw contains a thrust surface interacting with the movable part. 7. The boring mandrel according to claim 1, characterized in that it contains a screw to go into a wide range of settings.

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