RU1798047C - Bore head - Google Patents

Abstract

Usage: machine tool, hole machining on CNC machines with a drill-milling-boring group. The inventive spiral surface: 10 at the end of the shaft 11 elongated along the axis of the head, supplying the head with a single-arm lever 17 placed in the cavity of the head with the possibility of swinging and a spring 27 installed along the axis of the head, which allows to increase the accuracy of processing due increasing the accuracy of positioning the tool holder. In operation, turning the shaft 11 rotates the spiral surface 10 and the tool holder moves in the radial direction. Mobile connections of the tool holder with the lever 17 provide a smooth movement of the tool holder. 3 s.p. f-ly, 10 ill.

Description

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The invention relates to machine tool industry and can be used in CNC machines of a drilling, milling and boring group with automatic tool change.

The purpose of the invention is to remedy the noted drawbacks, i.e. increasing machining accuracy by increasing the positioning accuracy of the tool holder. .

In FIG. 1 shows a head with one tool holder, axial section; on fit. 2 - a head with two cutters connected by levers with a spring-loaded common swing axis, axial section; in FIG. 3 - head with two cutters connected by mutually spring-loaded levers, axial section; in FIG. 4 - a head with two cutters interacting with the shaft spiral by means of rotation bodies, axial section; in FIG. 5, 6, 7, 8 - sections aa in FIG. 2, BB in FIG. 3, BB in FIG; 3 and DG in FIG. 4 respectively; in FIG. 9 - head with two cutters connected by a spring, axial section; in FIG. 10 is a section DD in FIG. 9.

The head (Fig. 1) consists of the machine tool 3 of the casing fixed with clamps 1 in the spindle 2 with the cover 5 fixed by screws 4. The carrier cutter 7, tool holder 8, on which the concentric steps 9 are engaged, are mounted on the radial rails Q of the casing elongated along the axis of the head with a single start spiral 10, in particular, an Archimedes spiral made at the end of the front end of the axially movable shaft 11 mounted on the bearings 12, 13 of the housing. The shaft 11 is connected to the drive shaft 14, in particular, an elastic coupling 15, which provides a clearance-free transmission of rotation to the shaft 11 during its axial movement.

The tool holder 8 is connected via the pivot axis 16 to the rear end of the one-arm lever 17, the front end of which is provided with a swing 18. Mounted in the longitudinal grooves 19 of the housing or its cover 5, intersecting at an angle of 90 ° with its guides b and, in particular, intersecting the axis of the head . The lever 17 is connected by a spring 20 with a screw 21 regulating its tension, screwed into the housing wall.

The shaft 11 and the support 12 form, in particular, a screw-nut transmission, where the screw pitch is equal to the pitch of the spiral 10. To protect the housing cavity from the ingress of the chips, the grooves are made internal (not through) or closed with caps 22.

The head can be equipped with several, in particular two, tool holders equally spaced around the circumference with a tool or only with tools 23, 24, 25, whose bodies directly engage with the spiral 10 (Figs. 2, 3, 4, 9). In this case, the levers springing the cutters 23 to the axis of the head have a common swing axis 26, which is connected by a spring .27 installed along the axis of the head and a tension adjusting screw 28 screwed into the housing cover (Fig. 2), or the levers are connected by a spring 29 ( Fig. 3).

Cutters 24 can be spring loaded to

the axis of the head is also directly connected by a radially mounted spring 30 (Fig. 4), and the cutters are a 25 -5-shaped spring 31 mounted on the cutters with screws 32 (Fig. 9), Both cutters 23 (24, 25) and

5, the corresponding radial guides are: the housings are somewhat offset relative to each other along the axis of the head, and the apex of the posterior incisor has a greater l-year. -. :.} -. -}. . .-.

0 Tool holder 8 (cutters 23, 24, 2.5) engage directly with the spiral, or by means of a body of revolution, for example, a roller 33 sitting on the axis 34 (Fig. 4-8), which reduces friction force and increases the smoothness of movement of the cutter ..

The boring head (Fig. 1) works as follows. -.-. .-g. ;

Install the shank of the housing 3 heads in spindle2 of the machine and fix it

0 by means of radial clamps 1, which enter E; ring & shank groove with hydraulic cylinders and wedges located around the circumference in the spindle and acting on the outer ends of the clamps. In this case, the shaft 11 is connected by means of a coupling to the shaft 14 of the reversible drive of radial movement of the cutter passing through the spindle.

In the initial position, the tool holder 8 is at a minimum distance from the axis of the head, the shaft 11 g is in the extreme rear position, the spiral 10 is at a minimum distance from the support 12, the coupling 15 is in the most compressed state. In that

In the 5th position, the head provides processing of the minimum diameter of the hole, and in this case. The subject of the CNC machine tool is fixed to zero by means of sensors for the drive of radial movement of the cutter.

0 To ensure a smooth radial movement of the cutter with a screw 21, the force of the spring 20 is adjusted. The force can also be adjusted by rearranging the end of the spring in the holes of the lever 17

5 its length (not shown). In the process of this regulation, the final self-installation of the arc steps 9 and spiral 10 occurs;

By turning on the drive, rotate the shaft 14 and through the coupling 15 the shaft 1.1. Since in the support 12

(screw-nut transmission) the nut is stationary, then the rotary screw moves in the axial direction, i.e. the shaft 11 together with the spiral 10. In this case, the clutch gradually expands. The tool holder 8 engaged with the spiral 10 moves radially, providing a predetermined projection of the tool.

By turning on the spindle rotation drive, transmitted through the keys (not shown) to the boring head, and by relative movement of the head and the workpiece, the hole is bored.

The movable connections of the tool holder 8 with the lever 17 by means of the axis 16 and the lever 17 with the axle 18, as well as the axial movement of the axle 18 in the grooves 19, ensure smooth movement of the tool holder.

At the end of the treatment, the drive for radial movement of the tool is reversed and the tool holder is returned to its original position by means of a spring 20.

When machining with heads with two cutters, the front cutter with a smaller overhang performs roughing, and the rear cutter with a large overhang performs finishing in one pass, which increases productivity.

 To process curved surfaces, the axis 18 (26) is fixed against movement along the axis of the head, and the tool holder 8 (cutters 23, 24. 25) is installed in the guides 35 with a gap equal to the axial length of the spiral 10. Due to this, the cutters can move in both radial and axial directions.

Due to the fact that the spiral is elongated along the axis of the head, the technology of its manufacture is simplified, this makes it possible to grind the spiral surface on thread grinding machines, which increases the machining accuracy and smooth engagement of the tool holder 8 (cutters 23, 24, 25) with it.

The use of an elastic coupling and a screw-nut transmission also provides an increase in the smoothness of movement of the cutters.

Thus, the boring head in comparison with the prototype allows to increase the accuracy of processing due to the accuracy of positioning of the cutters.

For rm ul and zobretin

Claims (4)

1. A boring head comprising a housing with radial guides, a tool holder with a cutter and with an element designed to interact with a spiral surface made on the end of the shaft mounted in the cavity of the housing in the support with axial movement, while the other end is designed to interact with drive, characterized in that, in order to increase the accuracy of processing by increasing the accuracy of positioning of the tool holder, the spiral surface is elongated along the axis of the head, while a thread is made in the shaft and in the support, and said tool holder element is made in the form of concentric arc steps. 2. The boring head according to p. T, with the fact that it is with a single lever arm spring-loaded to the axis of the head, mounted in the cavity of the body on the axis with the possibility of swinging in the plane passing through the tip of the cutter and an axis of engagement and interaction with the tool holder, while longitudinal grooves are provided in the housing for being placed on the axis of said lever. 3. Boring head according to paragraphs. 1 and 2, which means that the spring is installed along the axis of the head and is connected with the axis of the lever. 4. The boring head according to claim 1, with the exception that, in order to increase the accuracy of machining curved surfaces, the axis of the lever is fixed in the grooves, and the tool holder is installed in the guides with a gap equal to the axial length spirals.