SU876327A1 - Tool head - Google Patents

Description

(54) TOOL HEAD

one

The invention relates to machine tools) and can be used to equip machine tools in which tool rotation is to be provided in at least two mutually perpendicular working machines,;

There are known heads for software movement of the tool relative to the workpiece, containing a carriage body moving along the machine guides, a spindle assembly pivotally fixed in the carriage body, and a two-coordinate mechanism for the programmable movement of the spindle assembly 1.

The known devices have relatively low accuracy and require the development of complex control programs.

The purpose of the invention is to improve processing precision and simplify programming.

This goal is achieved by the fact that the spindle assembly is equipped with two spherical hinges, one of which is installed in the carriage body, and the programmatic movement mechanism of the spindle assembly is mounted on the carriage body and is movable in two

perpendicularly movable frames with programmed drives with grooves, in the intersection zone of which a second spherical hinge is installed.

In addition, the two-coordinate program-displacement mechanism is made in the form of a gear pair with external gearing, and the center of one of the 10 gear wheels contains the spherical hinge case of the spindle assembly, and both wheels are mounted on axles with the possibility of rotation eccentrically, subject to

15

E „c geaA u + veAom. where is trtu. intercenter distance;

ftewhv

. instantaneous radii of the wheels in the link, measured along the line connecting the centers of the axes of rotation of the wheels.

FIG. 1 depicts the proposed

25 instrumental head, general view; in fig. 2 - spindle assembly of the proposed tool head, longitudinal section; in fig. 3 is a top view of the cross coordinate support of the two-coordinate mechanism of the programmable movement of the spindle unit, FIG. 4 is the same, cross section; FIG. 5 is a gear drive with external gearing of the two-axis mechanism of the spindle unit, longitudinal section; in fig. b - the same, top view.

The proposed tool head (Fig. 1) has a carriage body 1, made in the form of a rigid box-shaped frame, having on one side of the side guides 2 for communication with a CNC milling or other machine ram. In the carriage case 1 there is a spindle unit 3, having two (lower and upper relative to the fastening zone of the tool not shown in the drawings) spherical bearings 4 and 5. The lower spherical hinge 4 is installed in the carriage 1 body using a cushion cover b. The upper spherical hinge 5 is associated with the two-coordinate mechanism 7 software. moving spindle assembly 3.

The spindle assembly 3 (Fig. 2) has a quill 8, inside which a spindle 10 is mounted on rotary-thrust bearings 9, having a cone 11 in the lower part for mounting the mandrel with a tool, and a pulley 12 in the upper part for connection. to the rotation drive 13. The quill 8 is provided with two knots NvtyIv5 and spherical hinges 4 and 5, of which the lower 4 is rigidly connected (in particular, made zardno) with a quill, and the upper 5 is installed in a sliding fit and fixed in the cage 14 of the two-coordinate mechanism 7 of the programmatic movement.

Depending on the specific needs of production, the two-coordinate mechanism 7 of the programmatic movement of the spindle assembly 3 can be performed in various ways.

The most technologically advanced and therefore simple to manufacture and most convenient from the point of view of ease of programming tool movements in space is the implementation of mechanism 7 in the form of {cross support (fit. 3 and 4) consisting of rigid spatial frames 15 perpendicularly inserted into each other. and 16, slider 17, which is located in the zone of their intersection and having, a holder for the upper spherical hinge 5, and two ball screw screw drives 18 and 19, one of which is connected to the outer frame 16, se-carriage 1 and the second, associated with the inner frame 15, fixed to the outer frame 16 compound slide.

The cushioning elements of the cover b are chosen in such a way that the force to be broken by them is obviously greater than the reaction of the workpiece when processing, but less control forces that change the position of the spindle assembly 3 in space.

In the manufacture of relatively large series of parts with complex contours in the composition of the two-coordinate mechanism 7 of program movement, it is advisable to have a means of presetting the kinematic chain for processing parts of a particular type (Fig. 5 and 6). Such a mechanism has 0 two gears 20 and 21, mounted on the axles. 22 and 23 eccentric with respect to the conditions

mi .-eeAvui, .- bedomg consi,

where c. - intercenter distance 5e;

vedush ,.

and g are the instantaneous values of the radii of the wheels in meshing, measured along the line connecting the centers of the axles of the wheels. One of the gears 20 is made in the Central part at the same time with the spherical hinge holder 5, moving along the spindle spindle 8

node 3. The second wheel 21 may be made arbitrary in shape, for example, elliptical (Fig. b) or otherwise, depending on the type of products to be processed on the machine,

0 equipped with the described tool head. The magnitude of the initial eccentricity e (fig. B) of the position of the hinge 5 relative to the axis 22, the center-to-center distance CMU. And the shape of the wheel 21 are taken into account as the initial data when preparing the programs. In the initial position, the wheels 20 and 21 are engaged in such a way that the geometrical axis of the spindle unit 3 is

0 parallel to the guides 2 of the case of the carriage 1 and that the centers of the wheels 20, 21 and the hinge 5 are on the same straight line. Lead can be any of the gears 20 and 21.

5 The instrumental head works as follows.

Taking into account the shape of the part, the initial shape of the workpiece and the geometrical parameters of the head itself, it is known to prepare processing programs. In the process of implementation, prepared programs using an instrumental head having a cross support, including one or both actuators 18 and 19 of the cross support move frames 15 and 16 and a slider 17 associated with them, providing geometric summation of two movements and corresponding movement of the yoke. and spherical

0 hinge 5, which, slipping along the quill 8, transmits control of the force to the entire spindle assembly W ... In this case, the spherical hinge 4 turns in the holder of the carriage 1,

Claims (2)

5 provides for the movement of the tool along a given trajectory within a solid angle of 90 °. Similarly, the tool works on the head with a gear drive. two-coordinate mechanism for software movement. When the leading gear wheel rotates in gear pair 20 and 21, the center of the spherical hinge 5 changes relative to the axis of rotation of the gear wheel 20, which, respectively, causes the axis of the spindle assembly 3 to deviate from the vertical and the tool movement specified by the machining program. Independently from the form of execution of the two-coordinate mechanism 7 of the programmed displacement, the control actions are attached to the long arm of the lever of the nepJBoro kind, which is the spindle unit 3, and the workers reevaluate on a short plate Th, which substantially facilitates and accelerates the threefold training programs and increases the accuracy of movement of the tool along a predetermined path and machining accuracy. Reducing the impact of the workpiece on the operation of the software control mechanism also contributes to improving the processing accuracy and reduces the power and energy consumption of software control drives. The use of the proposed tool allows an increase in machining accuracy and simplified software control. Claim 1. Instrumental head for software movement of the tool relative to the workpiece, comprising a carriage body Movable along the machine guides, spindle unit. hinged in the carriage body, and a two-coordinate mechanism for programmable movement of the spindle assembly, characterized in that, in order to increase the processing accuracy and simplify programming, the spindle assembly is equipped with two spherical hinges, one of which is installed in the carriage housing, and the software mechanism The spindle assembly is mounted on the case-, carriage with the possibility of movement, and is made in the form of two mutually perpendicularly movable frames with programmed movement drives, equipped with x slots in the intersection zone set KOTO1ILH second spherical joint. 2. The head according to claim 1, is distinguished by the fact that the two-coordinate mechanism of the programmed movement is made in the form of a gear pair with external gearing, in which the center of one of the gear wheels is placed a spherical hinge sleeve of the spindle assembly, and both wheels are mounted on rotary axis x eccentrically with observance of conditions. neither: beAusch BeAomG ° in where K mi ,. intercenter distance; , instantaneous values of iVD ra. wheel diameter in the engagement, measured along the line connecting the centers of the axes of rotation of the wheels. Sources of information taken into account during the examination 1. V. Litsenko. Machine tools with numerical control. M., Mashgiz, 1979, p. 406. Uf.J / ff Is. (Rig. M