KR101537021B1

KR101537021B1 - Hydraulic spring-loaded drive

Info

Publication number: KR101537021B1
Application number: KR1020107008104A
Authority: KR
Inventors: 헨릭 로르베르그; 요아킴 에게르스; 클라우스 스틱커
Original assignee: 에이비비 테크놀로지 아게
Priority date: 2007-10-16
Filing date: 2008-09-30
Publication date: 2015-07-15
Also published as: KR20100077164A; WO2009049768A1; HUE024572T2; EP2198442A1; JP2011501057A; CN101933109B; CN101933109A; DE102007062291A1; EP2198442B1; JP5512526B2

Abstract

The present invention relates to a hydraulic spring-loaded drive, wherein the hydraulic spring-loaded drive comprises an actuating cylinder arranged in the actuating cylinder housing (12), at least one pre-loaded spring (10) And a pressure body (16) concentrically disposed about the operating cylinder housing (12), wherein the pre-loaded spring (10) comprises a plurality of pressure pistons Pushes the fluid present in the hole 32 under pressure by the pressure body 16 and the pressure piston 34. The guide ring 14 is radially disposed between the pressure body 16 and the operating cylinder housing 12 so that during the tensioning and during the relaxation of the pre-loaded spring 10, the guide ring 14 is axially Without being subjected to the force, the pressure body 16 is not axially urged when the pre-loaded spring 10 is pre-stressed.

Description

[0001] HYDRAULIC SPRING-LOADED DRIVE [0002]

The present invention relates to a hydraulic spring-loaded drive device according to the preamble of claim 1.

Such a spring-loaded drive is known from patent application EP 0829892 A1, especially from figure 3. Here, the accumulator spring allows fluid to flow under pressure through the pressure body and at least two pressure pistons. With this fluid, the drive rod moves, is fixed to the drive piston, and becomes slidably displaceable in the actuating cylinder. The pressure body is preferably annular in this case and is arranged concentrically around the operating cylinder housing.

When the spring-loaded drive is mounted, and also during maintenance operations, the hydraulic system is relieved of pressure. The accumulator springs are only prestressed in this state and have maximum axial expansion. In this case, the accumulator spring presses the pressure body against a stop on the operating cylinder housing, so that the pressure body is clamped between the stop and the accumulator spring.

While the spring-loaded drive is in operation, the hydraulic system is under pressure. The accumulator spring is further tensioned in this state, which then appears to be charged and its axial expansion is reduced. The accumulator spring in this case presses the pressure body against the pressure piston, which causes the pressure piston to flow under pressure. The pressure body is clamped between the pressure piston and the accumulator spring.

When the hydraulic system is not pressurized, the stop on the operating cylinder housing exerts a force on the pressure body in the radially inner region in the direction of the accumulator spring. When the hydraulic system is under pressure, the fluid exerts a force in the direction of the accumulator spring on the pressure body in the radially outer region through the pressure piston. In both cases, the accumulator springs in each case exert a counter-fully opposing force of the same magnitude on the pressure body.

When this opposite force radially acts on the pressure body on the inside, while the hydraulic system is under pressure, the opposite force is radially offset with respect to the force exerted by the pressure piston. When this opposite force radially acts on the pressure body on the outside, the opposite force is radially offset with respect to the force exerted by the stop, while the hydraulic system is not pressurized.

As a result of such radial force offsets, the pressure body is twisted under relatively high forces.

It is an object of the invention to develop a hydraulic spring-loaded drive device of the type mentioned at the beginning, in such a way that radial force offsets on the pressure body are avoided.

According to the invention, the guide ring is arranged in such a manner that the guide ring is not subjected to an axial force during the tensioning and during the relaxation of the accumulator spring, and in that the pressure body is subjected to axial stress Is radially disposed between the pressure body and the operating cylinder housing.

While the accumulator springs are tensioned and relieved, the accumulator springs pressurize radially onto the pressure body, especially at the distance from the mid-axis of the working cylinder housing, which is the same as the pressure piston. Thus, while the accumulator spring is under tension and relieves, radial force offsets on the pressure body and the guide ring are avoided.

As the accumulator springs are subjected to pre-stressing, the accumulator springs especially press against the radial guide ring on the inside, at a distance from the mid-axis of the same operating cylinder housing as the stops. Thus, even when the accumulator springs are pre-stressed, radial force offsets on the pressure body and the guide ring are avoided.

According to an advantageous refinement of the invention, the guide strip is fitted in the guide ring.

The guide strip improves the sliding characteristics of the guide ring on the operating cylinder housing.

Advantageous refinements and improvements of the present invention, as well as further advantages thereof, will be explained and described in more detail with reference to the drawings showing exemplary embodiments of the invention.

In the present invention, while the accumulator spring is tensioned and relieved, radial force offsets on the pressure body and the guide ring are avoided.

1 shows a hydraulic spring-loaded drive device according to the invention;

Figure 1 shows a hydraulic spring-loaded drive device according to the invention when the hydraulic system is free of pressure.

An accumulator spring 10 supported by a foot end on a support ring 22 located near the foot region 20 of the operating cylinder housing 12 is disposed about the operating cylinder housing 12. The accumulator spring 12 is a non- In this example, the accumulator spring 10 is designed as a cup spring assembly. Other types of accumulator springs, such as helical springs, may also be conceived.

The accumulator spring 10 urges the guide ring 14 against the stop 24 and presses against the head end lying on the guide ring 14 against the foot end. The stop 24 is located in the vicinity of the head region 26 of the operating cylinder housing 12 and the head region is located axially opposite the foot region 20. The region in which the accumulator spring 10 is pressed onto the guide ring 14 is at the same height as the stop 24 in the radial direction. Thus, the radial force offset between the force exerted by the accumulator spring 10 and the counter force exerted in the opposite direction by the stop 24 is avoided.

A container body 30 is disposed between the stop 24 and the head area 26 and is provided with a hole 30 which extends axially, that is, parallel to the mid-axis of the operating cylinder housing 12 32, wherein the pressure piston 34 is slidably displaceable. The piston rod 36 protruding from the hole 32 of the container body 30 is located at the end of the pressure piston 34 facing the accumulator spring 12.

The hydraulic spring-loaded drive system has at least two, preferably three, container bodies, each container body having a hole and a pressure piston located therein with a piston rod. These container bodies are disposed around the operating cylinder housing 12, and the mid-axis of the holes is at the same distance from the mid-axis of the operating cylinder housing 12. [ Only one container body is shown in this cross section.

A pressure body (16) is provided concentrically around the operating cylinder housing (12) and the guide ring (14). The pressure body 16 and the guide ring 14 are arranged in such a manner that during movement of the operating cylinder housing 12 toward the foot region 20 the pressure body 16 follows the guide ring 14, During movement of the housing 12 toward the head region 26, the guide rings 14 are axially intermeshed with each other in a manner that follows the pressure body 16.

The pressure body (16) and the guide ring (14) are arranged radially free of side by side. Therefore, the movement of the pressure body 16 in the radial direction relative to the guide ring 14 is not possible.

In order to improve the sliding characteristics of the guide ring 14 on the operating cylinder housing 12, the guide strip 18 is fitted in the guide ring 14.

In the example shown, that is, for a pressureless hydraulic system, the accumulator spring 10 is only pre-stressed. As the accumulator spring 10 of the spring-loaded drive is subjected to pre-stressing, the pressure body 16 is not axially urged. Therefore, the pressure body 16 is axially displaceable between the accumulator spring 10 and the piston rod 36.

In order to apply tension to the accumulator spring 10, the fluid is pumped by way of the pump 38 (not shown here) through the duct 38 into the hole 32, in particular to the region facing away from the accumulator spring 10 do. The fluid presses the piston rod 36 fixed to the accumulator piston 34 and the accumulator piston 34 in the direction from the hole 32 toward the accumulator spring 10.

In this case the piston rod 36 exerts an axial force on the pressure body 16 which in turn transfers this force onto the accumulator spring 10, (10) is compressed and thus receives tension. The pressure body 16 is clamped between the accumulator spring 10 and the piston rod 36 while the accumulator spring 10 is under tension and is urged in the direction toward the foot region 20 of the operating cylinder housing 12 . During this movement, the pressure body 16 follows the guide ring, and therefore this guide ring also moves in the direction of the foot area 20 side of the actuating cylinder housing 12.

After the predetermined operating pressure reaches the hydraulic system, the pump is stopped. The accumulator spring 10 is charged and the accumulator piston 34, the piston rod 36, the pressure body 16 and the guide ring 14 are fixed. The guide ring 14 is not subjected to axial force. Therefore, the guide ring 14 is axially displaceable between the accumulator spring 10 and the pressure body 16.

While the spring-loaded device is in operation, the accumulator spring 10 is relaxed in steps and simultaneously expands axially. In this case, the accumulator spring 10 presses the pressure body 16 and also urges the piston rod 36 and the accumulator piston 34 in the direction of the head region 26 side of the operating cylinder housing 12 To the hole (32).

During relaxation of the accumulator spring 10 the pressure body 16 is clamped between the accumulator spring 10 and the piston rod 36 and moves in the direction of the head region 26 side of the operating cylinder housing 12 do. During this movement, the accumulator spring 10 follows the guide ring 14, which therefore also moves in the direction of the head region 26 side of the actuating cylinder housing 12.

Even though the spring-loaded drive is in operation, the guide ring 14 is not axially urged and therefore axially displaceable between the accumulator spring 10 and the pressure body 16.

During tensioning and also during relaxation of the accumulator spring 10 the accumulator spring 10 presses the pressure body 16 against the head end and presses the pressure body 16 against the piston rod 36, do. The region in which the accumulator spring 10 is pressed onto the pressure body 16 lies in the radial direction at the same height as the piston rod 36. Thus, the radial force offset between the force exerted by the accumulator spring 10 and the opposing force exerted by the piston rod 36 in the opposite direction is avoided.

A support spring 28 is provided in the head region of the accumulator spring 10. The support spring 28 is part of the accumulator spring 10 and is of a rigid design so that the support spring 28 is not deformed or is only meaningless during the tensioning and during the relaxation of the accumulator spring 10. [ . The support springs 28 are arranged to always contact the guide ring 14 and / or the pressure body 16.

In the pre-stressed state of the accumulator spring 10, the support spring 28 presses the guide ring 14 against the stop 24. During the tensioning and also during the relief of the accumulator spring 10, the support spring 28 presses the pressure body 16 against the piston rod 36.

The accumulator spring 10 is axially guided at the head end by the guide ring 14 and the pressure body 16 in the pre-stressed state, and also during the tensioning and during the relaxation. The deflection of the head end of the accumulator spring 10 in the other direction, in particular in the radial direction, is thus prevented.

10: Accumulator spring
12: Operation cylinder housing
14: Guide ring
16: Pressure body
18: Guide strip
20: Foot area of the operating cylinder housing
22: Support ring
24:
26: head area of the operating cylinder housing
28: Support spring
30: container body
32: hole
34: Pressure piston
36: Piston rod
38: Duct

Claims

A hydraulic spring-loaded drive device, comprising: an operating cylinder disposed in an operating cylinder housing (12); at least one accumulator spring (10); and at least two container bodies each having a hole (32) Wherein at least two of the container bodies are disposed about the operating cylinder housing 12 and the mid-axis of the orifice 32 has a pressure piston 34 with a piston rod 36 of the operating cylinder housing 12 The pressure piston 34 is in each case at least two container bodies slidably disposed in the bore 32 and a pressure body 34 disposed concentrically around the operating cylinder housing 12, And the accumulator spring 10 comprises a hydraulic spring-loaded drive device for pushing the fluid located in the hole 32 under pressure through the pressure body 16 and the pressure piston 34 As a result,
The accumulator spring 10 is arranged radially between the pressure body 16 and the pressure piston 34 and is provided with a support spring 28 as part of the accumulator spring 10,
In the prestressed state of the accumulator spring 10 the support spring 28 is urged against the stop 24 disposed about the head region 26 of the actuating cylinder housing 12 against the guide ring 14)
During the tensioning and during the relaxation of the accumulator spring 10 the support spring 28 presses the pressure body 16 against the piston rod 36 and the guide ring 14 is axially urged Wherein the hydraulic spring-loaded drive device is a hydraulic spring-loaded drive device.

delete

The hydraulic spring-loaded drive device according to claim 1, characterized in that the guide strip (18) is fitted in the guide ring (14).