SU1392251A1 - Self-braking clamping device - Google Patents

Abstract

The invention relates to metalworking and can be used in automatic lathes. The goal is to increase clamping reliability. The self-braking clamping device contains a drive for supplying the working fluid, rotating with the hydraulic cylinder clamping the workpieces 1 with the main 2 and an additional 3 pistons

Description

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ni Me: waiting for the pistons, there are elastic force 5 and friction 6 elements. Between the main 2 and additional 3 pistons, a sleeve 4 with a collar is installed, along which the elastic elements 5,6 are centered. In the main piston 2, there are axial channels in which the pistons 12 are located with rods having bevels at the ends. In the radial bore of the main piston 2, a split elastic ring 1 4 is installed with a tapered inner and outer surface. In the axial channels of the sleeve are located the pushers 15 with a collar at one end and a bevel at the other. The collars of the pushers 15 are installed with the possibility of interaction with the elastic friction element 6. The bevels of the pushers 15 and the piston rods 12 interact with the conical surfaces of the ring 14. 2 Cp fg-ly, 4 Il.

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The invention relates to metalworking and can be used in automatic lathes and semiautomatic machines, as well as lathe boring machines, hydraulic or pneumatic drives for fastening bar and piece blanks.

The aim of the invention is to simplify the construction and increase the reliability of the clamp.

FIG. 1 shows the device, longitudinal section; in fig. 2 shows section A-A in FIG. one; in fig. 3 is a view B in FIG. one; in fig. 4 shows a section B-B in FIG. one.

The device consists of a rotating hydraulic cylinder 1 with a main 2 and an additional 3 pistons, between which is installed a centrifuge knob 4 with a collar. An elastic force element is installed between the collar and the main piston 2 in the form of a disk-spring pack 5, and depending on the required strain, the bag can be made with a parallel (as shown in Fig. 1) assembly or a serial assembly. Elastic friction element in the form of a package of disc springs 6 with one row of external radial slots (Fig. 2), made with a sequential assembly, which eliminates its slippage and axial movement of the pack deformation This, as well as ensures reliable fixation of the sleeve 4 relative to the hydraulic cylinder 1. At the other link 5 and the friction element 6, are centered along the sleeve 4. The main piston 2 through the clamp 7 pipe is rigidly connected to the clamp collet 8 installed in the conical bore of the spindle 9. The piston 2 has an axial bore 10 and a radial bore, in which a split elastic ring 11 is installed, hardened in a diluted state.

In the piston 2 parallel to its axis are made the bores in which are placed

pistons 12 with rods having bevels at the ends and installed with the possibility of contacting the bevels on the piston rods with the outer conical surface of the ring 11. The ring 13 attached to the piston 2 prevents the pistons 12 from falling out (FIG. 3). In the sleeve 4 there is a groove 14, the profile of which corresponds to the profile of the inner surface of the ring 11, as well as the axial holes in which the pushers 15 are installed. The pushers have bevels on one end and a shoulder on the other (FIG. 4), and the shoulder is placed between the springs 6,

The working fluid is supplied to the hydraulic cylinder 1 from the hydraulic distributor 16 through the pipeline 17 to the uncleaning cavity, and through the pipe 18 to the cavity of the hydraulic cylinder clamp. Both cavities are connected by a hydroline, which includes a choke 19 and a backflow controlled valve 20. Parallel to the hydroline line 18, a check valve 21 is installed, and a choke is installed on the drain behind the valve 16.

22. A pressure switch 23 is connected to the clamping line.

The device works as follows.

The working fluid under pressure from the power source through the hydraulic distributor 16 and the trunk 17 is fed into the left cavity of the hydraulic cylinder 1, and through the throttle 19 - into the control cavity of the reverse control valve 20. The main piston 2 moves together with the clamping pipe 7 and the collet 8 to the right, compressing the package of 5 springs and removing the tension of the elastic system No. 1 of the device. The sleeve 4, the friction one: the element 6 and the additional piston 3 are stationary at the same time, since the working fluid in the right cavity of the hydraulic cylinder of the cylinder 1 is locked by a valve 20, the opening of which is delayed due to the throttle 19. The springs 6 are maximally deformed and hold the sleeve 4 is stationary relative to the hydraulic cylinder. Under the pressure of the working fluid, the pistons 12 at the moment when the ring 11 turns against the groove 14, squeeze it into the groove, thereby fixing the position of the piston 2 relative to the sleeve 4. After the valve 20 is opened, the working fluid from the right cavity of the hydraulic cylinder is through the valve 20 valve 16 and throttle valve 22 are discharged into the tank. The piston 3 moves to the right, the spring package 6 is released, wedging sleeve 4, and the entire system, including piston 2, sleeve 4 and piston 3, moves to the right, creating a gap between the clamping surfaces of the collet 8 and the workpiece. The pushers 15 when wedging the pack 6 also move to the right.

After the piece or feed is installed up to the stop of the bar stock, the spool 16 is switched to the extreme left position. The working fluid under pressure from the power source through the hydraulic distributor 1b is supplied to the return controlled valve 20 through pipe 18 and the check valve 21, which passes the working fluid into the control cavity of the valve 20. The piston of the valve 20 is displaced to the right, the flow through, the main flow of working fluid in right cylinder cavity 1. Piston 2 and piston 3 together with clamping pipe

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7 and collet 2 are moved to the left by pre-clamping the workpiece. The spring package 5 remains deformed due to the working fluid backing created by the throttle 22, as well as the ring 11 fixing the piston 2 relative to the sleeve 4. After the piston 2 stops, the piston 3 moves to the left under the pressure of the liquid, which compresses the sleeve 4 relative to the hydraulic cylinder 1. At the same time, one of the springs of the package 6 (in Fig. 1 right) moves the pushers 15 to the left, which in turn, with their bevels, squeeze the ring 11 out of the groove 14. Since the ring is hardened, in diluted state diverges from the axis of the device and squeezes the pistons 12 to the left due to the fact that the fluid pressure in the left cylinder cavity is insignificant at this time. Moving the ring 11 from the axis of the device - PUSH unlocking the piston relative to the sleeve 4 and under the action of the package 5 of the springs the piston 2, and with it the pipe of the clamp 7 and the collet 8 move to the left, having carried out the final clamping of the workpiece. After this, the pressure switch 23 gives the command to switch the hydraulic distributor 16 to the neutral position at which the power source is connected to the drain, i.e. goes into idle mode.

The technical and economic efficiency of the proposed self-braking clamping device in comparison with the prototype is due to the simplified design, increased clamping reliability, and increased durability of hydraulic equipment.

Claims (3)

1. A self-locking clamping device containing a rotating hydrocylinder for clamping workpieces with a main and additional pistons located € 1H-HJe between them elastic force and friction elements and a hydraulic actuator, characterized in that, in order to increase the reliability of the clamp, between the main and additional ports, a sleeve with a radial collar is installed, the elastic frictional element is made in the form of a package of successively assembled dish-shaped pipes with radial slots and is placed between the collar of the sleeve and the additional piston, and the elastic force element is between the collar of the sleeve and the main piston. 2. The device according to claim 1, characterized in that in axial channels made in the main piston, pistons are installed with rods made with bevels at the ends, in a radial bore made in the main piston, an elastic split ring with conical inner and outer surfaces, axial holes made in the sleeve, installed pushers made with shoulders at one end and with bevels at the other, the bevels of the rod pushers are arranged with the possibility of interaction with the outer and inner surfaces of the elastic split ring. 3. The device according to PP. 1 and 2, characterized in that the pusher flanges are arranged to interact with an elastic friction element. 9аъ.Ц