RU193800U1 - DRILL SHORTED HIGHER RIGIDITY WITH SMP FOR PROCESSING HOLES IN RAILS - Google Patents

Abstract

The utility model relates to the field of mechanical engineering and can be used in the construction of metal-cutting tools, in particular drills. The drill contains a housing with a tail and working parts, peripheral, central and chamfer cutting plates located on the working part of the body, chip grooves made with decreasing depth to the tail part and located on the side of the peripheral and central cutting plates, and channels for cutting fluid going into the chip grooves. The central cutting insert is made with a non-linear cutting edge and mounted with rotation relative to the axis of symmetry of its mounting hole, and the peripheral cutting insert is mounted with rotation relative to the axis of symmetry of its mounting hole with the formation together with the central cutting plate of a non-linear working cutting edge of the drill. The radial component of the cutting force during processing is reduced, the roughness and waviness of the surface are reduced, and the drill resistance is increased. 1 s.p. f-ly, 6 ill.

Description

The invention relates to the field of engineering, and in particular to the designs of metal-cutting tools, in particular drills.

A drill is known (patent No. 2432237), which is chosen for the closest analogue, comprising a housing, an internal cutting insert mounted next to the axis of rotation and having an axis of symmetry and an axisymmetric contour having four cutting edges and four rounded corners, an external cutting insert identical to inner cutting insert. In this case, the outer cutting insert is mounted farther from the axis of rotation than the inner cutting insert. The rotation paths of the inner cutting insert and the outer cutting insert are at least partially overlapped to form a overlap portion in which the cutting edge of the inner cutting insert and the cutting edge of the outer cutting insert are inclined to the axis of rotation towards the workpiece, and the rotation path of the cutting edge of the inner cutting insert protrudes in the direction of the part along the axis of rotation of the housing in comparison with the path of rotation of the cutting edge of the outer cutting insert. Effect: increase productivity, reduce the required reserves of cutting inserts, facilitate their installation and replacement through the use of identical cutting inserts.

The disadvantages of this technical solution that impede the obtaining of a technical result, which is ensured by the claimed invention are: the drill body does not have structural elements that increase the rigidity necessary to minimize the displacement of the axis of the drill from the radial component of the cutting force. Also, this technical solution does not provide the geometry of the cutting part necessary to compensate for the radial component of the cutting force.

The invention relates to the field of engineering, and in particular to the designs of metal-cutting tools, in particular drills. A drill is known (patent for invention No. 2402410), which has a longitudinal axis of rotation and includes a channel extending mainly along the axis for the passage of fluid, a socket for a cutting insert open to the peripheral surface of the cutting tool through an outlet and connected to the channel, a cutting insert installed in the nest with the possibility of sliding and moving from the retracted position to the extended position by the pressure of the fluid, which acts on it and biases in the direction to the extended position. In the extended position, at least a portion of the cutting insert protrudes from the outlet above the peripheral surface of the cutting tool. The tool also contains a threaded fastener to prevent the insert from coming out of the socket and limit its rotation around its axis. Effect: the expansion of technological capabilities due to the integration of the cutting plate near the grooves of the drill.

The disadvantages of this technical solution that impede the receipt of a technical result, which is ensured by the claimed invention are the complicated design of the drill element, which performs a chamfer on the hole being machined. The movable connection between the bevel element and the drill body reduces the reliability of the entire structure due to the fact that under the influence of high temperature that occurs during the drilling process and a significant part of it is transferred to the drill body, jamming can occur. As a result, the entire structure will fail.

Thus, the task to which the claimed utility model is directed is to create a drill design, the geometry of the cutting part of which will help to reduce the radial component of the cutting force. It will also help to reduce the roughness and waviness of the machined surface of the drilled hole due to the cylindrical thickening between the chamfering cutting plate and the tail portion, which will significantly increase the rigidity of the drill body. The solution of this problem will be achieved through a combination of features given in the relevant paragraphs of the utility model formula. In particular, a rail drill is proposed, comprising a housing with a tail and working parts, peripheral, central and chamfer cutting inserts located on the working part of the housing, chip grooves made with decreasing depth to the tail part and located on the side of the peripheral and central cutting inserts, and channels for the cutting fluid leaving the chip grooves, characterized in that the central cutting insert is made with a non-linear cutting edge and is mounted with rotation of the relative but the symmetry axis of its mounting hole, and the peripheral cutting insert is mounted pivoting about an axis of symmetry of its fastening openings to form with the rectilinear central cutting insert operative cutting edge of the drill. The working part between the bevel cutting plate and the tail part is made with a cylindrical thickening.

The essential features of the proposed utility model that are distinguishing from the nearest analogue and ensure the achievement of the indicated technical result are: the central cutting insert is made with a non-linear cutting edge and mounted with rotation about the axis of symmetry of its mounting hole, and the peripheral cutting insert is installed with rotation about the axis of symmetry of its mounting holes with the formation together with the Central cutting plate of an indirect working mode boiling drill edge, which compensates the radial component of the cutting force; the working part between the bevel cutting plate and the tail part is made with a cylindrical thickening, which provides a significant increase in the rigidity of the working part and, as a result, a decrease in the waviness and roughness of the machined hole surface.

The essence of the utility model is illustrated by drawings, which depict:

In FIG. 1 - presents a General view of the drill from the working part;

In FIG. 2 is a view of a KK drill body;

In FIG. 3 - view G from the end face of the working part of the drill;

In FIG. 4 shows a view B perpendicular to the front surface of the central cutting insert and a cross-section EE perpendicular to the axis of rotation of the drill in the area of the fixing screw of the central plate;

In FIG. 5 is a view B perpendicular to the front surface of the facet cutting insert and a section DD perpendicular to the cutting edge of the facet plate in the area of the fixing screw;

In FIG. 6 shows a view A perpendicular to the front surface of the peripheral cutting insert and a section MF perpendicular to the cutting edge of the peripheral insert in the area of the fixing screw.

Rail drill, comprising a housing 1, with a tail and working parts, a peripheral 2, a central 3 and a chamfer 4, cutting inserts located on the working part of the housing 1, chip grooves 5, 6, made with decreasing depth to the tail part and located on the peripheral side 2, and the central 3, cutting inserts, and channels for cutting fluid 7 that exit into the chip grooves 5, 6, characterized in that the central 3, cutting insert is made with a non-linear cutting edge 9, and is mounted with rotation relative to about si symmetry of its mounting hole 8, and the peripheral 2, the cutting insert is mounted with rotation relative to the axis of symmetry of its mounting hole 8, with the formation together with the Central 3, cutting plate of a non-linear working cutting edge of the drill. Also at the drill the working part between the bevel 4, the cutting insert and the tail part is made with a cylindrical thickening.

The proposed utility model has been introduced in the production of rail-beam workshops of such enterprises as: EVRAZ NKMK, Novokuznetsk, EVRAZ NTMK, Nizhny Tagil, MECHEL Chelyabinsk, ARBZ, Aktyubinsk (Kazakhstan). The implementation of this utility model is confirmed by acts on positive production tests and long-term contracts and agreements for the use of this drill design in the main production.

Claims (2)

1. Rail drill, comprising a housing with a tail and working parts, peripheral, central and chamfer cutting plates located on the working part of the housing, chip grooves made with decreasing depth to the tail part and located on the side of the peripheral and central cutting plates, and channels for cutting fluid leaving the chip grooves, characterized in that the central cutting insert is made with a non-linear cutting edge and is mounted with rotation about its axis of symmetry of the mounting hole, and the peripheral cutting insert is mounted pivoting about an axis of symmetry of its fastening openings to form with the rectilinear central cutting insert operative cutting edge of the drill. 2. The drill according to claim 1, characterized in that the working part between the bevel cutting plate and the tail part is made with a cylindrical thickening.

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