RU136380U1 - DEVICE FOR STABILIZING THE POSITIONS OF THE AXES OF THE PROCESSED HOLE AND THE TOOL - Google Patents

Abstract

A device for stabilizing the positions of the axes of the hole to be machined and the tool, comprising a displacement sensor, two-coordinate electronic levels and a numerical control system (CNC), characterized in that it contains electro-hydraulic converters, amplifiers of electrical signals and two small movements made in the form of hydraulic jacks, each of which is installed in the area of the guides of the machine bed at the junction between the rails and the machine stand.

Description

The utility model relates to the field of mechanical engineering, mainly to high-precision machine tools, and can be used in precision machines of the boring and milling groups with a horizontal spindle.

A device for stabilizing the power deformations of the bed, containing an additional support of the machine, made in the form of a hydraulic jack, mounted on the foundation at the place of greatest deflection of the bed and containing a programmable logic controller that controls the force of the hydraulic jack, preventing the appearance of bending deformations of the bed [1].

The disadvantage of this device is the frequent occurrence of errors

control due to various disturbing influences, which can be elastic deformations of the bed due to the forces of the weight of the moving units and the weight of the workpieces, as well as wear of the mating surfaces. This, in turn, leads to repeated readjustments, complication and cost of maintenance of technological equipment.

In the patent [2], a method for improving the accuracy of the machine by spatial control of the position of the bed with the table and the machined case blank relative to the foundation is presented. Management is carried out using four hydraulic jacks installed around the perimeter of the bed.

A disadvantage of the known solution is the significant effect of contact deformations at the joints of the bed-table and work-table subsystems, which have a significant effect on the output accuracy of the machine.

A hydraulic jack is installed in the device [3] for compensating the mutual angular displacements of the tool axes and the bored hole between the table and the workpiece being processed. Using a hydraulic jack, the angular displacements of the body blank relative to the machine table are controlled.

The disadvantage of this device is the reduction in the rigidity of the installation of the machined body blank relative to the table.

In the patent [4], a device is considered for compensating the angular displacements of the axes of the machined hole and the tool due to bending deformation, which is achieved by placing a small displacement mechanism made in the form of an electromagnet in the joint between the rails on which the stand is mounted and the stand with the tool fixed to it. direct current.

The disadvantage of this device is that it does not compensate for the deformation of the frame due to torsion.

The objective of this utility model is to ensure stabilization of the positions of the axes of the machined hole and tool due to bending and torsion of the bed.

This problem is solved due to the fact that the device for stabilizing the position of the axes of the machined hole and the tool, containing a displacement sensor, two-coordinate levels and a program control system, additionally contains electro-hydraulic converters, amplifiers of electrical signals and two small displacement mechanisms made in the form of hydraulic jacks, each of which It is installed in the area of the bed guides and is located at the junction between the rails and the machine stand.

Figure 1 shows a General view of a horizontal coordinate-boring machine, equipped with a device for stabilizing the positions of the axes of the machined hole and tool. The machine consists of a bed 1, mounted on three rigid supports 2, 3 and 4 relative to the foundation. On the guides of the bed in the direction of the OZ axis on the slide 5, the stand 6 moves, with a spindle head 7, containing a spindle unit 8 with a fixed cutting tool, the movement of which along the OY axis is carried out using an electric motor 9 (M). Processed on the machine body blank 10 is mounted on the table 11 of the machine. The case blank is installed on the mounting supports. The device contains mechanisms of small displacements 12 and 12 ', made in the form of hydraulic bearings. The device includes two-coordinate electronic levels 13, 14, (EU ₁ , EU ₂ ), a slide sensor 15 with a rack along the bed guides, a CNC system 16 (CNC), electric signal amplifiers 17, 17 'and electro-hydraulic transducers 18, 18' (EGP).

The electronic levels of EU ₁ and EU ₂ determine the tilt angles α ₁ , β _{1 of the} rack (FIG. 4, FIG. 5) and the tilt angles of the workpiece α ₂ , β ₂ (FIG. 4, FIG. 5) due to bending and torsion of the bed . Analog or digital outputs from the levels are connected to the CNC system of the machine.

Figure 2 shows a top view of a horizontal coordinate boring machine, which shows the frame 1, supports 2, 3, 4, slide 5 with a stand 6 installed and a headstock 7, with spindle 8, the workpiece 10 on the table 11 and hydraulic supports 12 and 12 '.

Figure 3 presents the device of the hydraulic bearings introduced at the junction between the rails and the rack. The rack is mounted on a slide and connected to the pusher 19 of the hydraulic support and secured using a stud 26 with a nut 27 and a washer 28. The lower end of the stud is screwed into the threaded hole of the pusher, which is fixedly connected to the rigid center 20.

The hydraulic support consists of a housing 23, which is screwed into the base 24 along a threaded thread. Through the fitting 25, a working fluid is supplied to the housing of the hydraulic support 23, the pressure of which is regulated in the electro-hydraulic converter. Using an elastic membrane 22, the variable pressure produces translational movement of the rigid center 20 and, accordingly, the angular movement of the front edge of the rack. The cover 21 is screwed to the housing 23 with fixing screws, presses a tightly elastic membrane and creates a tight connection.

Figures 4, 5 show the geometry of angular displacements due to torsional deformations and bending of the bed that occur during the movement of the rack in the direction of the workpiece, which lead to a loss of accuracy of the technological system of the machine. The reason for this is the mutual deviation of the axes of the bored holes and the tool, due to the angular movements of the workpiece and stand.

6, 7 show structural diagrams of stabilization of the positions of the axes of the tool and the machined hole, which shows the following notation:

Uin - input signal (input state);

Uout - output signal (state at the output);

U is the control action;

EU ₁ - electronic level mounted on a rack;

EU ₂ - electronic level installed on the workpiece;

α ₁ - the angle of inclination of the axis of the rack due to torsion strain;

α ₂ - the angle of inclination of the axis of the workpiece due to torsion strain;

β ₁ - the angle of inclination of the axis of the rack due to bending deformation;

β ₂ - the angle of inclination of the axis of the workpiece due to bending deformation;

CNC - numerical control system (CNC);

U - electric signal amplifier;

EGP - electro-hydraulic converter;

GO - hydraulic support;

DP - displacement sensor;

M - motor displacement along the axis OY;

ШУ - spindle unit.

The bed 1 begins to scroll and bend when moving the slide 5 with the rack 6 along the guides in the direction of the OZ axis (figure 1). The signals y (α ₁ ) and y (α ₁ ) (Fig. 4) of two-coordinate electronic levels 13 and 14 mounted on the rack 6 and the body blank 10 determine the angular displacements of the axis of the rack αi and the axis of the workpiece α ₂ .

The signals y (α ₁ ) and y (α ₂ ) from electronic levels enter the numerical control system 16 (CNC) (Fig. 1), where they are compared with each other and a correction command is sent based on their difference (Fig. 6):

Δy (α) = y (α ₂ ) -y (α ₁ )

This command arrives at the electro-hydraulic transducers 18, 18 ', which regulate the pressure of the working fluid in the hydraulic bearings 12, 12' (Fig. 1). Under the action of pressure of the working fluid on the pushers 19, 19 '(Fig. 3), the stand rotates through an angle α ₂ -α ₁ to stabilize the torsion strain of the bed (Fig. 4). After that, the signals y (α ₁ ) and y (α ₂ ) are repeatedly compared, and if Δу (α) ≠ 0, then the correction is repeated.

Thus, the proposed device can significantly reduce the influence of torsion and bending of the bed on the accuracy of the technological system of the machine by stabilizing the positions of the axes of the machined hole and tool.

Information sources:

1. Pat. 74839 of the Russian Federation for a utility model, IPC V23V 25/06. The device for stabilization of force bending deformations of the bed of a horizontal boring machine / Gorshkov B.M., Krasnov S.V., Samokhina N.S., Lysak P.M., Vyunov A.V., Zagrebin K.V. Bull. No. 20, 2007.

2. Pat. 3807034 United States, IPC B23Q 11/00; G05B 19/404. Method of truing up heavy workpieces on the table of a metal-cutting machine and such table for carrying said method into effect / Semen Pevzner, Viktor Koire 1974.

3. Pat. 85389 RF for utility model, IPC: B23Q 23/00 A device for compensating mutual angular displacements of the tool axes and the bored hole / Samokhina N.S., Gorshkov B.M., Denisenko A.F., Trubacheva S.I., Marshanskaya O. V., Zagrebin K.V. Bull. No. 22, 2009.

4. Pat. 109036 RF for a utility model, IPC: B23Q 23/00 A device for compensating angular displacements of the axes of a tool and a machined hole / Vylegzhanin D.V., Remneva O.Yu., Gorshkov B.M., Samokhina N.S., Schlegel O.A. ., 2010.

Claims (1)

A device for stabilizing the positions of the axes of the machined hole and the tool, containing a displacement sensor, two-coordinate electronic levels and a numerical control system (CNC), characterized in that it contains electro-hydraulic converters, amplifiers of electrical signals and two small displacement mechanisms made in the form of hydraulic jacks, each of which is installed in the area of the guides of the machine bed at the junction between the rails and the machine stand.

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