SU757778A1 - Hydraulic drive - Google Patents

Description

The invention relates to machine tools and can be used in automated machines for processing products that differ in shape or have different allowance for machining.

Known hydraulic actuator, consisting of a hydraulic motor with the translational movement of the output Even (hydraulic cylinder), pressure hydraulic line connected 10 with the rod cavity of the hydraulic cylinder and the hydraulic line of the free drain, and drain through the throttle connected to the rodless cavity of the hydraulic cylinder {Ύ].

The specified hydraulic drive when moving the piston 15 of the hydraulic cylinder to the right allows for quick movement of the piston, and when the bead enters the bore of the lid - to drain through the throttle, performing ·· braking of the piston 20 with unstressed feed to the hydraulic cylinder cover and stopping the movement, however after braking.

The closest to the proposed 25 hydraulic actuator contains a hydraulic motor, the cavities of which are communicated by hydrolines with a power source and a tank, and one of the cavities is communicated with the tank by two complementary hydrolines,

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one of which has adjustable hydraulic / resistance, and the other - distributor [2],

The disadvantage of this hydraulic drive is that it does not allow to regulate and implement a smooth increase in the pressure drop in the cavities of the hydraulic engine, as well as to maintain its constant value in the future.

The purpose of the invention is to increase productivity by automating the process of increasing the pressure drop in the cavities of a hydraulic engine, as well as improving the smoothness of changes in the differential.

This goal is achieved by the fact that in addition to the distributor in front of the distributor, reduction and check valves are installed in series. In the second additional hydraulic line, before the hydraulic resistance, a valve is installed, containing a spool, on one of the belts of which grooves are formed, which form a variable-choke choke with the valve body.

In addition, the valve is equipped with a throttle bore regulator, made in the form of a restrictive stop.

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Figure 1 schematically shows the hydraulic actuator, in which the output link of the hydraulic cylinder is made in the form of a rod, the leftmost position of the piston; .2 - piston position at the entrance to the body bore; FIG. 3 is a variant of the hydraulic drive, in which the communication of the rodless cavity of the hydraulic cylinder with the tank is carried out through a distributor controlled from a cam mounted on the rod; figure 4 is the same, the output link of the hydraulic cylinder is made in the form of a shaft-gear.

The hydraulic actuator (see Fig.1.2) contains a hydraulic cylinder 1, in the case of which the piston 2 is located. The piston 2 is provided on the left side with a rod 3, and with a right-shoulder turret 4 having the ability to enter the bore 5 of the case. The shtavaya cavity 6 of the hydraulic cylinder 1 is connected to a power source (not shown) of the pressure head 7 and the line 8. Parallel to the line 8, a pressure valve 9 is installed, limiting the pressure in the pressure line 7 by draining the excess liquid from the line 10 to tank 11. The rodless cavity 12 of the hydraulic cylinder 1 is communicated by hydroline 13 to the tank 11. In addition, the cavity 12 is communicated with the tank by additional hydraulic lines 14 and 15. In hydraulic line 14, valve 16 and adjustable hydraulic resistance 17 are installed in series. Hydraulic line 1 5, a valve 18, a reducing valve 19 and a check valve 20 are installed in series. The valve 16 is designed in the form of a housing 21 in which a spool 22 is placed. On the strap 23 of the spool there are grooves 24 forming alternating choke with a housing 21. Springless control cavity 25 of the valve communicates with hydroline 14 control line 26, and in the specified cavity is placed a regulator, made in the form of a restrictive stop 27.

The hydraulic actuator in the embodiment of FIG. The '3 further comprises a distributor 28 controlled by a cam 29 mounted at the end of the rod 3 of the hydraulic cylinder 1.

The hydraulic actuator in the embodiment of FIG. 4 contains a hydraulic cylinder 1, the piston 2 of which is made in the form of a rail connected with its teeth to the shaft-gear 30. In the case of the hydraulic cylinder 1 there is an annular groove 31 connected to the hydraulic line 13.

The hydraulic actuator works as follows.

When the working fluid is injected under pressure into the hydroline 7, the cavity 6 of the hydraulic cylinder 1 is filled and the piston 2 moves to the right. From the cavity 12 of the hydraulic cylinder, the working fluid is discharged by the flow, which determines the speed of the rapid movement of the piston 2 through the hydraulic line 13 and the hydraulic line

14 through hydraulic resistance

17 merges during this period a slight fluid flow.

At the entrance of the collar 4 of the piston 2 into the bore 5 of the housing, the volume of fluid bounded by the collar and boring is forced out through the hydraulic resistance 17 and the grooves 14, which determine the speed of movement of the piston 2 in the braking section.

Under the action of the pressure of the working fluid in the bore 5 transmitted to the cavity 25 of the valve 16 along the control line 26, the valve 22 is mixed to the right, and discharge from the cavity formed by the collar 4 and the bore 5 occurs through the hydraulic resistance 17 into the tank 11. When the output link touches load pressure in the cavity 6 increases, and in the cavity bounded by the collar '4 and bore 5, decreases. When this valve 22 is shifted to the left, and the working fluid is displaced through the grooves 24, which contributes to a smoother decrease in pressure in the cavity bounded by the collar 4 and boring 5 and, consequently, a smoother increase in pressure on the piston 2. By selecting the appropriate profile and length of the grooves 24 and "By placing the stop 27", you can adjust the smoothness of the increase in pressure drop on: the piston of the hydraulic cylinder, and, consequently, the forces acting on the piston 2.

With increasing pressure drop on the piston 2 due to the pressure drop in the cavity bounded by the collar 4 and the bore 5, below the nominal / non-return valve 20 under the action of pressure opens and feeds the specified cavity until the nominal pressure is established. After that, the valve 20 automatically divides the specified cavity and the reducing valve 19 for a period until the pressure in the cavity again becomes less than the nominal one. Thus, at a constant drain pressure and maintaining the pressure in the cavity at a predetermined level, the piston 2 maintains a constant pressure drop and, consequently, a constant force acting on the piston.

In the embodiment of the hydraulic drive of FIG. 3 hydraulic actuator operates as follows. ·

From the pressure line 7, the working fluid under pressure enters the cavity 6 of the hydraulic cylinder 1, and the piston 2 quickly moves to the right, discharging the working fluid from the cavity 12 through the distributor 28 and through the hydraulic line 13 into the tank 11.

When the cam 29 hits the distributor 28, the latter switches to the upper working position, and the working fluid from the hydraulic cylinder cavity 12 is displaced through the distributor 28, through the hydraulic line 14 through the hydraulic resistance 17 into the tank 11,

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and the pressure in cavity 6 increases. The piston 2 moves to the speed of slow movement. Otherwise, the operation of this hydraulic variant is similar to the operation of the device shown in FIG. 1 and 2. 5

In the embodiment of the hydraulic drive of FIG. 4 hydraulic actuator works as follows.

From the pressure line 7, the working fluid under pressure is injected into the cavity of the hydraulic cylinder 1, and the piston 2 quickly moves to the right, turning the gear shaft 30. After the piston 2 overlaps the ring groove 31, the working fluid from the cavity 12 of the hydraulic cylinder 1 is not merged by hydraulic line · 13, and through the hydrolines 14, through the hydraulic resistance 17, as a result of which the pressure in the cavity 6 increases and the piston 2 and the gear shaft 30 perform braking and go over to 20 the speed of slow movement. Further, the operation of the hydraulic drive is similar to the above.

Automating the process of smoothly raising and switching to the mode of regulating the constant pressure drop on the piston of a hydraulic engine allows you to increase productivity, for example, when working with a tool on a part on the machine, and to increase tool life.

Claims (3)

Claim 1. The hydraulic actuator, the contents of the hydraulic motor, the cavities of which are communicated hydrolines with a power source and a tank, and one of the cavities communicates with the tank by two additional hydrolines, in one of which there is an adjustable hydraulic resistance, and in the other - distribution. In order to improve performance by automating the process of increasing the pressure drop in the cavities of the hydraulic engine, in the additional hydraulic line, in front of the distributor, reduction and check valves are installed in series. , 2. Hydraulic pop. 1, characterized in that, in order to increase the smoothness of the change in pressure drop, a valve containing a spool is installed in front of the hydraulic resistance in the additional hydroline, on one of the belts of which are grooves forming a variable-flow choke with the valve body. 3. Hydraulic pop. 2, which is tactile in that the valve is equipped with a throttle bore regulator, made in the form of a restrictive stop.