Pressure balancing device and engineering machinery

Abstract

The present disclosure provides a pressure balancing device and an engineering machine. The pressure balancing device comprises: a housing; a movable body, which is arranged in the housing so as to be reciprocatingly movable along a first direction; an isolation element, which is sealedly arranged between the housing and the movable body, and the isolation element and the movable body separate the internal space of the housing into a first cavity and a second cavity which are isolated from each other, the first cavity being configured to be filled with a fluid whose pressure is to be balanced, and the housing forming the second cavity having a communication port for communicating with the external environment of the pressure balancing device; and an elastic element, which is arranged in the second cavity and applies a force along the first direction and toward the first cavity to the movable body.

Description

Technical Field

[0001] The present disclosure relates to the technical field of engineering machinery, and in particular to a pressure balancing device and engineering machinery. Background Art

[0002] For underwater engineering machinery, such as trenching machines, the external pressure on the drive device increases as the working depth increases. At this time, the drive device is at risk of entering muddy water due to seal failure. To prevent such risks, a pressure balancing device can be set to make the oil pressure inside the drive device equal to or slightly greater than the external pressure.

[0003] In the related technology known to the inventor, the pressure balancing device adopts a split water pressure balancer of a bladder and a spring booster type. The external water pressure is sensed by the bladder, and then the external environmental pressure is transmitted to the water pressure balancer through a hose. A spring is provided in the water pressure balancer to achieve the technical effect of pressurizing the oil. Summary of the invention

[0004] A first aspect of the present disclosure provides a pressure balancing device, comprising:

[0005] case;

[0006] A movable body is disposed in the housing so as to be reciprocatable along a first direction;

[0007] an isolation element, sealingly disposed between the housing and the movable body, the isolation element and the movable body dividing the internal space of the housing into a first cavity and a second cavity isolated from each other, the first cavity being configured to be filled with a fluid to be pressure balanced, and the housing forming the second cavity having a communication port for communicating with an external environment of the pressure balancing device;

[0008] The elastic element is disposed in the second cavity and applies a force to the movable body along the first direction and toward the first cavity.

[0009] In some embodiments, a guide structure is further included, wherein the guide structure is configured to guide the movable body to move along the first direction, and the guide structure includes a rotation-stopping portion, wherein the rotation-stopping portion is configured to prevent the movable body from rotating around an axis extending along the first direction.

[0010] In some embodiments,

[0011] The guide structure includes a sleeve and a guide rod, wherein the sleeve extends along the first direction and is disposed on one of the housing and the movable body, and the guide rod extends along the first direction and is disposed on the other of the housing and the movable body, and the guide rod extends into the sleeve and is reciprocally movable along the sleeve;

[0012] The anti-rotation portion includes a protrusion and a groove, the protrusion is arranged on one of the sleeve and the guide rod along the first direction and is located between the sleeve and the guide rod, the groove is arranged on the other of the sleeve and the guide rod along the first direction and is located between the sleeve and the guide rod, and the protrusion is slidably fitted with the groove.

[0013] In some embodiments, the elastic element includes a first spring and a second spring that are coaxial and nested inside and outside, the two ends of the first spring and the second spring respectively abut against the housing and the movable body, and the first spring and the second spring are spiral springs with opposite rotation directions.

[0014] In some embodiments, a blocking structure is further included, and the blocking structure is disposed between the first spring and the second spring along a radial direction of the first spring and the second spring.

[0015] In some embodiments, the barrier structure includes two barrier rings spaced apart along the first direction, and the two barrier rings are respectively disposed on the housing and the movable body.

[0016] In some embodiments, a limiting structure is further included, and the limiting structure includes:

[0017] a limiting rod, wherein a first end of the limiting rod is fixed to the movable body, and a second end of the limiting rod extends from the shell forming the second cavity; and

[0018] The limiting block is detachably connected to the second end of the limiting rod.

[0019] In some embodiments, the pressure balancing device further includes a detection element configured to detect a position of the movable body in the housing.

[0020] A second aspect of the present disclosure provides an engineering machine, comprising the pressure balancing device of the first aspect of the present disclosure.

[0021] In some embodiments, the construction machine comprises a slotting machine.

[0022] Based on the pressure balancing device provided by the present invention, by setting a connecting port connecting the second cavity with the external environment, the bladder can be eliminated, providing conditions for setting a larger diameter shell and a large diameter cavity. Setting a large diameter cavity is beneficial to improving the oil replenishment sensitivity of the pressure balancing device when replenishing oil for the working device connected to the first cavity, resulting in a large oil replenishment amount, small pressure fluctuation and more stable performance.

[0023] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure. In the drawings:

[0025] Figure 1 Schematic diagram of the structure of the pressure balancing device according to the embodiment of the present disclosure.

[0026] Figure 2 for Figure 1 A schematic diagram of the partial cross-sectional structure of the pressure balancing device of the illustrated embodiment. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0028] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0029] In the description of the present disclosure, it should be understood that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present disclosure.

[0030] In the description of the present disclosure, it should be understood that the orientation or positional relationship indicated by the directional words is usually based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0031] In the process of realizing the present disclosure, the inventor found that the pressure balancing device of the above related technology can balance the pressure of the working device such as the driving device connected thereto and the external environment, but there are also certain shortcomings. The pressure balancing device of the above related technology occupies a large space due to the split structure. Since the bladder is used to sense the external water pressure, the bladder itself has a certain thickness. When the water pressure is transmitted to the inside of the bladder, it first needs to overcome the resistance of the bladder deformation, which leads to pressure loss, and the hose also has pressure loss when transmitting pressure. Once the working device connected to the pressure balancing device leaks, the oil in the bladder needs to be replenished in the water pressure balancer. Since the diameter of the pipeline connecting the bladder and the water pressure balancer cannot be too large, the flow rate of the oil is limited, that is, the oil filling speed and sensitivity of the water pressure balancer are limited. Since the split type occupies a large space, the diameter of the water pressure balancer is small in the limited installation space. Under the same oil filling amount, the rolling diaphragm of the water pressure balancer has a large movement stroke and a low life of the rolling diaphragm. The spring of the water pressure balancer will twist the rolling diaphragm during the reciprocating motion, further reducing the service life of the rolling diaphragm.

[0032] To solve the above problems, Figure 1 As shown, an embodiment of the present disclosure provides a pressure balancing device, which includes a housing 1 , a movable body 3 , an isolation element 4 and an elastic element 2 .

[0033] The movable body 3 moves along the first direction Figure 1 The middle part is arranged in the housing 1 so as to be reciprocally movable in the up-down direction.

[0034] The isolation element 4 is sealed and disposed between the housing and the movable body 3. The isolation element 4 and the movable body 3 separate the internal space of the housing into a first cavity 103 and a second cavity 104 which are isolated from each other. The first cavity 103 is configured to be filled with a fluid to be pressure balanced, and the housing 1 forming the second cavity 104 has a communication port 106 for communicating with the external environment of the pressure balancing device.

[0035] The balancing fluid is filled in the first chamber 103. The balancing fluid is a fluid that needs to be pressure balanced, such as oil.

[0036] The elastic element 2 is disposed in the second cavity 104 and applies a force along a first direction and toward the first cavity 103 to the movable body 3 .

[0037] In the pressure balancing device of the disclosed embodiment, the isolation element 4 and the movable body 3 change the volumes of the first cavity 103 and the second cavity 104 under the combined action of the pressure of the balancing fluid, the elastic element 2 and the external environment. By providing a connecting port connecting the second cavity with the external environment, the bladder can be eliminated, providing conditions for providing a shell with a larger diameter and a large-diameter cavity. The provision of a large-diameter cavity is conducive to improving the oil replenishment sensitivity of the pressure balancing device when replenishing oil for the working device connected thereto, with a large oil replenishment amount, small pressure fluctuation, and more stable performance.

[0038] like Figure 1 and Figure 2 As shown, in some embodiments, the pressure balancing device further comprises a guide structure configured to guide the movable body 3 to move along the first direction, and the guide structure comprises a rotation stopper configured to prevent the movable body 3 from rotating around an axis along the first direction.

[0039] like Figure 1 and Figure 2 As shown, in some embodiments, the guide structure includes a sleeve 105 and a guide rod 302. The sleeve 105 extends along the first direction and is disposed on one of the housing 1 and the movable body 3. The guide rod 302 extends along the first direction and is disposed on the other of the housing 1 and the movable body 3. The guide rod 302 extends into the sleeve 105 and is configured to be reciprocatingly movable along the sleeve 105. The anti-rotation portion includes a protrusion 304 and a groove 109. The protrusion 304 is disposed on one of the sleeve 105 and the guide rod 302 along the first direction and is located between the sleeve 105 and the guide rod 302. The groove 109 is disposed on the other of the sleeve 105 and the guide rod 302 along the first direction and is located between the sleeve 105 and the guide rod 302, and the protrusion 304 is slidably matched with the groove 109.

[0040] like Figure 1As shown, in some embodiments, the elastic element 2 includes a first spring 201 and a second spring 202 that are coaxial and nested inside and outside, and the two ends of the first spring 201 and the second spring 202 are respectively against the shell 1 and the movable body 3, and the first spring 201 and the second spring 202 are spiral springs with opposite rotation directions.

[0041] like Figure 1 As shown, in some embodiments, the pressure balancing device includes a baffle structure, which is arranged between the first spring and the second spring along the radial direction of the first spring and the second spring. For example, the baffle structure includes two baffle rings 303 arranged at intervals along the first direction, and the two baffle rings 303 are respectively arranged on the housing 1 and the movable body 3.

[0042] like Figure 1 As shown, in some embodiments, the pressure balancing device further includes a limiting structure, which includes a limiting rod 307 and a limiting block 306. The first end of the limiting rod 307 is fixed to the movable body 3, and the second end of the limiting rod 307 extends from the housing 1 forming the second cavity 104. The limiting block 306 is detachably connected to the second end of the limiting rod 307.

[0043] like Figure 1 As shown, in some embodiments, the pressure balancing device further includes a detection element 5 , which is configured to detect the position of the moving body 3 in the housing 1 .

[0044] The following combination Figure 1 and Figure 2 The embodiments of the present disclosure are described in more detail.

[0045] like Figure 1 As shown, the pressure balancing device includes a housing 1 , a movable body 3 , an isolation element 4 , an elastic element 2 , a guide structure, a limiting structure, a baffle structure and a detection element 5 .

[0046] The housing 1 includes a top cover 101 and a lower cylinder 102. The top cover 101 and the lower cylinder 102 are detachably connected together by connecting bolts. In this embodiment, the up-down direction is used as the aforementioned first direction. The movable body 3 is movably arranged in the housing 1 along the up-down direction.

[0047] The isolation element 4 is connected between the shell 1 and the movable body 3. The isolation element 4 and the movable body 3 divide the internal space of the shell 1 into a first chamber 103 located at the upper part and a second chamber 104 located at the lower part. The isolation element 4 always maintains sealing during the up and down movement of the movable body 3. The first chamber 103 of the pressure balancing device is connected to the working device and is used to fill the fluid to be balanced, such as the oil of the working device. A connecting port 106 is provided on the wall surface of the shell 1 corresponding to the second chamber 104. The connecting port 106 connects the second chamber 104 with the external environment, so that the pressure in the second chamber 104 can be the same as the external environment. For example, when the pressure balancing device is underwater, the pressure of the second chamber 104 is the pressure of the water level.

[0048] Compared with the pressure balancing device of the related art, the embodiment of the present disclosure is conducive to setting a larger diameter of the housing 1, achieving the purpose of shortening the stroke of the isolation element 4 under the same oil replenishment amount, and is conducive to increasing the service life of the isolation element 4. Moreover, when a working device connected to the pressure balancing device leaks, the oil in the pressure balancing device is replenished into the working device. Under the same oil replenishment amount, the spring rebound stroke of the pressure balancing device of the embodiment of the present disclosure is smaller, that is, the elastic force of the spring is reduced less, so that the pressure fluctuation of the entire pressure balancing device is small and the performance is more stable.

[0049] The elastic element 2 is located in the second cavity 104 and includes two coil springs, a first spring 201 and a second spring 202. The two ends of the two springs are respectively in contact with the inner wall surface of the bottom wall of the housing 1 and the bottom surface of the movable body 3, thereby providing an upward force for the movable body 3.

[0050] like Figure 1 As shown, the first spring 201 and the second spring 202 of the elastic element 2 have different rotation directions. On the one hand, the two springs will not get stuck with each other during the movement, and on the other hand, they can offset each other's rotational torsion generated when a part of the springs are stretched and contracted. For example, the first spring 201 located on the radial outer side is set as a right-handed spring, and the second spring 202 located on the radial inner side is set as a left-handed spring.

[0051] A plurality of connecting ports 106 are provided at the bottom and circumference of the lower cylinder 102. When the pressure balancing device is working, oil is filled into the first cavity 103 to compress the spring, and the fluid in the external environment, such as water, enters the second cavity 104 of the shell 1 through the connecting ports 106. Therefore, the pressure in the first cavity 103 is equal to the sum of the external environment pressure and the pressure generated by the spring rebound.

[0052] like Figure 1 As shown, the isolation element 4 can be a rolling diaphragm, the radial outer end of the rolling diaphragm is fixed between the top cover 101 and the lower cylinder 102, and the radial inner end is fixed to the upper surface of the movable body 3 through a pressure ring 301.

[0053] In some embodiments not shown in the figure, the isolation element 4 can also be a bellows, a metal foil, or a sealing element directly provided on the movable body 3, as long as it can separate the shell 1 into the first cavity 103 and the second cavity 104 together with the movable body 3, and always maintain the sealing during the movement of the movable body 3 along the first direction.

[0054] The guide structure includes a sleeve 105, a guide rod 302 and a rotation stopper. The rotation stopper includes a protrusion 304 and a groove 109. The sleeve 105 is arranged at the lower part of the top cover 101 along the up-down direction, and the groove 109 is arranged on the inner surface of the sleeve 105 along the up-down direction. The guide rod 302 is fixed above the movable body 3 along the up-down direction, and moves up and down with the movable body 3. The upper part of the guide rod 302 is located in the sleeve 105, and the protrusion 304 is arranged on the outer surface of the guide rod 302 along the up-down direction. The protrusion 304 on the guide rod 302 cooperates with the groove 109 in the sleeve 105.

[0055] On the one hand, the above guide structure can provide guidance for the up and down movement of the movable body 3, prevent the movable body 3 from swinging left and right, thereby protecting the isolation element 4, which is beneficial to improving the service life of the isolation element 4; on the other hand, during the spring expansion and contraction process of the elastic element 2, the end of the spring will rotate, and the rotation of the end of the spring will drive the movable body 3 and the isolation element 4 fixed on the movable body 3 to rotate together. The rotation of the isolation element 4 will cause damage to it, and its service life will be greatly reduced. The protrusion 304 on the guide rod 302 cooperates with the groove 109 in the sleeve 105, which can prevent the isolation element 4 from rotating, thereby helping to improve the service life of the isolation element 4.

[0056] like Figure 2 As shown, the groove 109 in the sleeve 105 is an internal spline, evenly distributed at three locations along the circumference, with two spline teeth set at each location, and the corresponding protrusion 304 on the guide rod 302 is an external spline, evenly distributed at three locations along the circumference, with one spline tooth set at each location.

[0057] In an embodiment not shown in the figure, the number and position of the internal splines and the external splines can be configured as needed, and can also be provided as other forms of anti-rotation parts.

[0058] In this embodiment, the joint surface of the top cover 101 and the lower cylinder 102 is set to zero position, and the movable body 3 can usually drive the isolation element 4 to move upward and downward for a certain stroke relative to the zero position. Once the stroke exceeds the corresponding range, the isolation element 4 is easily damaged and the pressure balance device loses its function.

[0059] The limiting structure includes a limiting rod 307 and a limiting block 306. The first end of the limiting rod 307 is fixed to the movable body 3, and the second end of the limiting rod 307 extends from the housing 1 forming the second cavity 104. The limiting block 306 is detachably connected to the second end of the limiting rod 307, for example, by a threaded connection.

[0060] When the isolation element 4 is damaged and needs to be replaced, the top cover 101 needs to be removed from the lower cylinder 102, and the spring will restore to the free length with the movable body 3 and pop out quickly, which is very dangerous. When the new isolation element 4 is reinstalled, since the free length of the spring is greater than the height of the isolation element 4, it is necessary to use tools and external force to compress the spring to a certain stroke before the radial outer end of the isolation element 4 can be fixed between the top cover 101 and the lower cylinder 102, and the radial inner end can be fixed on the upper surface of the movable body 3. In order to solve this problem, a limit block 306 is installed at the bottom of the guide rod 302, so that after the top cover 101 is removed, the spring will not rebound excessively due to the action of the limit block 306, making the replacement of the isolation element 4 convenient and quick.

[0061] The blocking structure includes two blocking rings 303 arranged at intervals at the bottom of the movable body 3 and the bottom of the lower cylinder 102, and the first spring 201 and the second spring 202 are concentrically placed on the inner and outer sides of the blocking ring 303. The blocking structure prevents the spring from moving radially during the expansion and contraction process.

[0062] like Figure 1 As shown, the detection element 5 is mounted on the top cover 101 , and the detection rod 501 of the detection element 5 extends into the guide rod 302 , and the guide rod 302 is provided with a sensing element 305 .

[0063] The detection element 5 can be, for example, a displacement sensor. The detection element 5 can detect the position of the movable body 3 in real time, and on the one hand, remind the user to add oil in time when the movable body 3 is at the upper limit position, and stop adding oil when the movable body 3 is at the lower limit position. On the other hand, the leakage of the working device can be judged according to the movement speed of the movable body 3, and abnormal leakage can be discovered in time, so as to lift the working device out of the water in time.

[0064] In an embodiment not shown in the figure, the detection element 5 may also include a plurality of proximity switches, for example, a plurality of proximity switches may be provided on the sleeve 105 at the lower part of the top cover 101 to detect the upper limit position and the lower limit position of the movable body 3. According to the above description, the pressure balancing device of the embodiment of the present disclosure has at least one of the following advantages:

[0065] By providing a connecting port connecting the second cavity with the external environment, the bladder can be eliminated, providing conditions for providing a larger diameter shell and a large diameter cavity. The large diameter cavity is conducive to improving the oil replenishment sensitivity of the pressure balance device, with a large oil replenishment amount, small pressure fluctuation and more stable performance.

[0066] The guide rod is provided with a protrusion, and the sleeve matched with the guide rod is provided with a groove. The cooperation between the two can not only provide guidance but also resist rotation, thereby preventing the spring from driving the movable body to rotate during movement, thereby preventing the isolation element from having its life reduced and being damaged.

[0067] The elastic element includes two concentrically placed springs with different rotation directions, which is beneficial to reducing the volume of the elastic element and the installation space of the elastic element, making the structure of the pressure balancing device more compact; the two springs of the elastic element have different rotation directions. On the one hand, the two springs will not get stuck to each other during movement, and on the other hand, they can offset each other's rotational torque generated when a part of the springs are stretched and contracted, thereby increasing the service life of the isolation element.

[0068] The limiting structure includes a limiting rod and a limiting block installed at the bottom of the limiting rod. When replacing the isolation element, after removing the top cover, the spring will not rebound excessively due to the action of the limiting block, making the work of replacing the isolation element convenient and quick.

[0069] The disclosed embodiment also provides an engineering machine, including the aforementioned pressure balancing device. The engineering machine, for example, includes a slotting machine. The engineering machine has the advantages of the aforementioned pressure balancing device.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solution for protection requested by the present disclosure.

Claims

1. A pressure balancing device, characterized in that: include: Housing (1); A movable body (3) is disposed in the housing (1) so as to be reciprocally movable along a first direction; an isolation element (4) which is sealingly disposed between the housing and the movable body (3); the isolation element (4) and the movable body (3) separate the internal space of the housing into a first chamber (103) and a second chamber (104) which are isolated from each other; the first chamber (103) is configured to be filled with a fluid whose pressure is to be balanced; and the housing (1) which forms the second chamber (104) has a communication port (106) for communicating with the external environment of the pressure balancing device; and An elastic element (2) is arranged in the second cavity (104) and applies a force to the movable body (3) along the first direction and toward the first cavity (103).

2. The pressure balancing device according to claim 1, characterized in that: It also includes a guide structure, which is configured to guide the movable body (3) to move along the first direction, and the guide structure includes a rotation-stopping portion, which is configured to prevent the movable body (3) from rotating around an axis extending along the first direction.

3. The pressure balancing device according to claim 2, characterized in that: The guide structure comprises a sleeve (105) and a guide rod (302); the sleeve (105) extends along the first direction and is arranged on one of the housing (1) and the movable body (3); the guide rod (302) extends along the first direction and is arranged on the other of the housing (1) and the movable body (3); the guide rod (302) extends into the sleeve (105) and is arranged to be reciprocatingly movable along the sleeve (105); The anti-rotation portion includes a protrusion (304) and a groove (109), wherein the protrusion (304) is arranged on one of the sleeve (105) and the guide rod (302) along the first direction and is located between the sleeve (105) and the guide rod (302), and the groove (109) is arranged on the other of the sleeve (105) and the guide rod (302) along the first direction and is located between the sleeve (105) and the guide rod (302), and the protrusion (304) is slidably matched with the groove (109).

4. The pressure balancing device according to any one of claims 1 to 3, characterized in that: The elastic element (2) comprises a first spring (201) and a second spring (202) which are coaxial and sleeved inside and outside, the two ends of the first spring (201) and the second spring (202) respectively abut against the housing (1) and the movable body (3), and the first spring (201) and the second spring (202) are helical springs with opposite rotation directions.

5. The pressure balancing device according to claim 4, characterized in that: It also includes a blocking structure, which is arranged between the first spring and the second spring along the radial direction of the first spring and the second spring.

6. The pressure balancing device according to claim 5, characterized in that: The barrier structure comprises two barrier rings (303) arranged at intervals along the first direction, and the two barrier rings (303) are respectively arranged on the shell (1) and the movable body (3).

7. The pressure balancing device according to any one of claims 1 to 3, characterized in that: It also includes a limiting structure, which includes: a limiting rod (307), wherein a first end of the limiting rod (307) is fixed to the movable body (3), and a second end of the limiting rod (307) extends from the housing (1) forming the second cavity (104); and The limiting block (306) is detachably connected to the second end of the limiting rod (307).

8. The pressure balancing device according to any one of claims 1 to 3, characterized in that: It also comprises a detection element (5), wherein the detection element (5) is configured to detect the position of the moving body (3) in the housing (1).

9. An engineering machine, characterized in that: The invention comprises the pressure balancing device according to any one of claims 1 to 8.

10. The construction machine according to claim 9, characterized in that: The engineering machinery includes a groove forming machine.

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