RU2466004C2 - Micromotion and microfeed drive - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to precision machinery building and serves for use in drives of micro-motions and micro-feeds. Invention contains executive bellows actuator, feeding device in a form of two bellows coaxially installed in bracket with middle moving wall that is connected by one side to nut via ball screw-and-nut assembly that actuates engine and by the other side it can be fixed for performing operating and accelerated movements relatively to piston that connects bellows actuator housing to executing assembly. In the course of fixing one of the walls relative to fixed element for selecting corresponding value of micro pitch and beginning of micro-pitch movements of bellows actuator housing and executing assembly connected to it, two other walls are fixed relatively to bellows actuator housing.

EFFECT: provision of independent formation of value of each charge micro-pitch in multi-charge bellows actuator.

1 dwg

Description

The invention relates to precision engineering and can be used in feed drives of metalworking machines, robots and manipulators to provide micro-stepping and micro-feed actuators with variable micro-steps and stepped working (accelerated) movements by one drive.

Known stepper feed drive containing an executive bellows hydraulic cylinder, a metering device in the form of two coaxially mounted bellows in the bracket with a middle movable wall connected by one side to the nut of a ball screw pair (ball screw), which is driven by a reversing stepper motor, and the other can be fixed for the implementation of working and accelerated movements relative to the rod connecting the cylinder body to the actuating unit, and a block of fixing clips for fixing the bracket, rod and the middle movable walls of three pairs of power bellows of the hydraulic cylinder with one or another code ratio of the effective cross-sectional areas, moreover, fixing one of the walls relative to the fixed element means choosing the appropriate microstep and the inclusion of one or another discharge of the hydraulic cylinder for micromotion (see RF patent No. 2351451).

The disadvantage of this drive is the inability to form the microstep by a pair of power bellows of each discharge, regardless of other discharge bellows.

An object of the invention is the independent formation in a multi-digit hydraulic cylinder of the microstep of each discharge.

This technical problem is achieved by the fact that in the drive of microdisplacement and micropods containing an executive bellows hydraulic cylinder, consisting of six power bellows installed coaxially in a common case, pairwise differing in effective cross-sectional area in accordance with some code and having common central movable walls, which each individually can be fixed relative to the fixed element, and the other two to eliminate the influence on the microstep of the remaining power bellows specifically the body of the hydraulic cylinder, which means the choice of the microstep size and the inclusion of a particular discharge of the hydraulic cylinder for microdisplacement, while the right cavities of each pair of power bellows are connected to the right, and the left, respectively, to the left cavity of the metering device, made in the form of two coaxially mounted bellows , the fixed sides of which are limited by the bracket, and the middle movable wall on one side is rigidly connected to the ball screw driven by the motor (stepper or motor DC m), and the other side for working or accelerated movements can be fixed relative to the rod fastened to the cylinder housing and the actuator assembly.

The drawing shows a schematic diagram of the described drive microdisplacement and micropods.

The drive includes an executive hydraulic cylinder, consisting of a housing 1 and three pairs of coaxially mounted bellows 2, 3 and 4, differing in effective cross-sectional area in one or another code, with central movable walls 5, 6 and 7, which individually can be fixed by clamps 8, 9 and 10 relative to the body of the hydraulic cylinder or clamps 11, 12 and 13 relative to the fixed element, which allows you to select the microstep, a metering device, consisting of two coaxially mounted bellows 14, 15, fixed sides which are limited by the bracket 16, fixed by the clamp 17, and the middle movable wall 18 can be fixed on one side relative to the rod 19 (with the clamp 20 and the stops 21), fastened to the hydraulic cylinder body and the actuating unit (not shown in the drawing), the clamp 22, and the other side rigidly connected to the ball screw 23, driven by a motor 24 (stepper or DC motor). Through the shutter 25, a one-time filling of the cavities of the pairs of power bellows 2, 3 and 4, metering bellows 14, 15 and the connecting line is made with the working fluid, and the filling is done so that when the working fluid is supplied under pressure, the central movable wall 18 is set strictly to its original position between the stops 21.

The drive operates as follows. To carry out accelerated or working movements by the drive, a clamp 22 is turned on, fixing the middle movable wall 18 of the metering device relative to the rod 19 (the clamps 8, 9, 10, 11, 12, 13 and 17 are disconnected), as a result of which the rod 19, the cylinder body 1 , the actuating unit and the middle movable wall 18 are moved as a whole in one direction or another from the engine 24 through the ball screw 23 at a speed determined by the control frequency.

At the end of the accelerated movement, the clamp 22 is turned off and the clamp 17 is turned on, which makes the drive ready for microstep movements.

For microstep movements, the actuating unit to the right by the engine 24 through the ball screw 23 is used to set the stepwise movement to the right of the middle movable wall 18 of the metering device. The bellows 15 begins to compress, and the bellows 14 to expand, as a result of which portions of the working fluid are displaced by pulses with a control frequency from the bellows 15 and are piped into the right cavities of the pairs of bellows 1, 3 and 4, increasing the pressure in them, which leads to the movement of the middle moving walls 5, 6 and 7 in the direction of lower pressure, i.e. to the left, and displacing the working fluid from the left cavities into the bellows 14.

Fixing one of the movable walls 5, 6 or 7 relative to the fixed element by means of clamps 11, 12 or 13, and the other two relative to the cylinder body by means of clamps 8, 9, 10 means choosing the microstep and starting the movement of the cylinder body 1, rod 19 and the actuating unit to the right with a given control frequency.

At the end of the microstepping movement, the position of the rod 19, and hence the actuating unit, is fixed by the clamp 20.

When all the included clamps are disconnected (clamp 22 has been disconnected earlier), the system returns to its initial state, which makes it ready to repeat the cycle.

Similarly to the considered microstepping movement of the actuating unit occurs to the left.

Claims (1)

A stepper drive drive of the actuating unit, comprising an actuating hydraulic cylinder, made in the form of three pairs of power bellows coaxially mounted in a common housing connected to the rod and the actuating unit, differing in effective cross-sectional area and having common middle movable walls, each of which is made with the possibility of fixing the rod and the actuating unit, and a metering device made in the form of two bellows coaxially mounted in the bracket with an average movable wall, one side of the cat The hole is connected to the nut with a ball screw pair driven by a stepper motor or a DC motor, and the other side can be fixed on the rod, characterized in that each of the common middle movable walls is made to be fixed relative to the fixed drive element, while fixing one of the aforementioned common middle movable walls relative to the stationary drive element, the other two middle movable walls are fixed relative to the cylinder body.