Internal liquid inlet balance jack

Abstract

The utility model belongs to the technical field of jacks, and particularly relates to an internal liquid inlet balance jack. A first liquid channel and a second liquid channel are formed in the jack piston rod, the first liquid channel is communicated with a piston rod cavity, and the second liquid channel is communicated with a piston cavity. The first liquid channel comprises an axial section and a plurality of radial sections communicated with the axial section and the piston rod cavity, the axial section extends to the extending end of the piston rod, and all the radial sections are located on the same section of the axial section; a pipeline with the diameter smaller than that of the axial section is installed in the axial section, the axial section and the pipeline are coaxially arranged, and the pipeline is a second liquid channel communicated with the piston cavity. Therefore, according to the jack, the first liquid channel and the second liquid channel for supplying liquid to the piston rod cavity and the piston cavity are arranged in the piston rod, so that the liquid inlet pipe is prevented from being rusted and damaged by moisture in a working environment or bent and damaged by external force, and the balance jack can normally work better and longer under severe working conditions; and the maintenance cost is further reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of jacks, and particularly relates to an internal liquid-filled balancing jack. Background Art

[0002] The balancing jack is one of the two most important jacks in the use of hydraulic supports. It is mainly used to connect the top beam and the shield beam to ensure the stability of the two-column shield support and keep the support in a good working posture. It can be used to adjust the top beam to a horizontal state or a required angle to keep the adjacent supports in a good sealing state. It is generally equipped with a balanced two-way lock and a safety valve to make the balancing jack tensile or thrust to adapt to the changes in the top plate load.

[0003] At present, there are two forms of liquid inlet for balancing jacks: one is to weld the upper and lower chamber joint seats on the cylinder, and connect them to the hydraulic control one-way valve by a hose. The hydraulic control one-way valve has no fixed installation position and is usually installed on the support structure nearby. This connection method is cumbersome, with a large number of interfaces, increasing the use of hoses, and a high probability of rust damage. The other is to weld the liquid inlet pipe and the valve plate on the cylinder to connect the upper and lower chambers. This connection method makes the liquid inlet pipe easily bent or damaged in the harsh environment of extremely thin coal seams underground, and it cannot be replaced, increasing maintenance costs. Utility Model Content

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the utility model provides an internal liquid inlet balancing jack, thereby solving the technical problem that the rubber hose or liquid inlet pipe of the external liquid inlet hydraulic support balancing jack is easily damaged, which increases the maintenance cost.

[0006] (II) Technical solution

[0007] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:

[0008] The utility model provides an internal liquid-intake balancing jack, comprising a cylinder barrel and a piston rod which are coaxially sleeved, a piston cavity and a piston rod cavity being formed between the two, a first liquid channel and a second liquid channel being formed inside the piston rod, the first liquid channel being communicated with the piston rod cavity, and the second liquid channel being communicated with the piston cavity; the first liquid channel comprises an axial section and a plurality of radial sections which communicate the axial section with the piston rod cavity, the axial section extends to the protruding end of the piston rod, and all the radial sections are located at the same cross-section of the axial section; a pipeline with a diameter smaller than the axial section is installed in the axial section, the axial section and the pipeline are coaxially arranged, and the pipeline is the second liquid channel which is communicated with the piston cavity.

[0009] Furthermore, the axial section has a first hole opened on the piston end of the piston rod, and the first hole is provided with an annular plug to seal the first liquid channel and the piston chamber; the annular plug is sleeved on the outside of the pipeline; the pipeline has a liquid port located at the piston end of the piston rod, and the liquid port connects the second liquid channel and the piston chamber.

[0010] Further, the axial length of the annular plug is smaller than the distance from the position of the radial section in the axial section to the first hole.

[0011] Furthermore, all radial segments are distributed bilaterally symmetrically with respect to a cross section of the axis where the axial segment is located.

[0012] Furthermore, the radial section has a plurality of second holes opened on the side wall of the piston rod, and all the second holes are distributed at equal intervals in the circumferential direction.

[0013] Further, the radius of the pipe is 0.55-0.65 times the radius of the axial section, so that the volume between the axial section and the pipe matches the volume of the pipe.

[0014] Furthermore, a hydraulically controlled valve is provided at the extended end of the piston rod, and a one-way valve which is sealed and connected to the first liquid channel and the second liquid channel respectively is provided on the hydraulically controlled valve.

[0015] Furthermore, a pipe interface is provided on the hydraulic control valve, and the pipe interface is sealed and connected to a safety valve.

[0016] (III) Beneficial effects

[0017] The beneficial effects of the utility model are:

[0018] The utility model provides an internal liquid-inlet balancing jack. Since the first liquid channel and the second liquid channel for supplying liquid to the piston rod cavity and the piston cavity are built into the piston rod, compared with the prior art, it avoids the difficulties of a large number of interfaces and complicated connection methods when a liquid inlet pipe is arranged outside the cylinder barrel, reduces the use of hoses, and avoids the liquid inlet pipe being damaged by rust due to moisture in the working environment, or being bent and damaged by external forces, so that the balancing jack can work better and longer under harsh working conditions, thereby reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the internal liquid balance jack;

[0020] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure.

[0021] [Description of Reference Numerals]

[0022] 1: Cylinder;

[0023] 2: piston rod; 21: axial section; 211: annular plug; 22: radial section; 23: pipeline;

[0024] 3: Piston chamber; 4: Piston rod chamber. DETAILED DESCRIPTION

[0025] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0026] Example 1

[0027] like Figure 1-2 As shown, the utility model provides an internal liquid-filled balancing jack, including a cylinder barrel 1 and a piston rod 2 which are coaxially sleeved, and a piston chamber 3 and a piston rod chamber 4 are formed therebetween. A first liquid channel and a second liquid channel are formed inside the piston rod 2, and the first liquid channel is connected to the piston rod chamber 4, and the second liquid channel is connected to the piston chamber 3.

[0028] The first liquid channel includes an axial section 21 and a plurality of radial sections 22 connecting the axial section 21 and the piston rod chamber 4 . The axial section 21 extends to the protruding end of the piston rod 2 , and all radial sections 22 are located at the same cross section of the axial section 21 .

[0029] By distributing all radial segments 22 symmetrically about the cross section of the axis where the axial segment 21 is located, the pressure can be evenly distributed.

[0030] A pipe 23 having a smaller diameter than the axial section 21 is installed in the axial section 21. The axial section 21 and the pipe 23 are coaxially arranged. The pipe 23 is a second liquid channel connected to the piston chamber 3. The pipe 23 has a liquid through hole located at the piston end of the piston rod 2, and the liquid through hole connects the second liquid channel and the piston chamber 3. The radius of the pipe 23 is 0.55-0.65 times the radius of the axial section 21, so that the volume between the axial section 21 and the pipe 23 matches the volume of the pipe 23.

[0031] The axial section 21 has a first hole opened on the piston end of the piston rod 2, and the first hole is provided with an annular plug 211 that seals the first liquid channel and the piston chamber 3 so that the liquid in the piston rod chamber 4 flows back to the extended end of the piston rod 2 in the first liquid channel and the liquid in the first liquid channel can only be supplied to the piston rod chamber 4. At the same time, the annular plug 211 is sleeved on the outside of the pipeline 23 to provide support for the pipeline 23. In order to avoid blocking the flow of liquid in the radial section 22, the axial length of the annular plug 211 is set to be smaller than the distance from the position of the radial section 22 located in the axial section 21 to the first hole.

[0032] In addition, a hydraulically controlled valve (not shown in the figure) is provided at the extended end of the piston rod 2, and a one-way valve is provided on the hydraulically controlled valve, which is sealed and connected to the first liquid channel and the second liquid channel respectively. The hydraulically controlled valve is fixed by bolts. When the piston rod 2 is extended to a specified length, the hydraulically controlled valve is closed to lock the jack.

[0033] At the same time, a pipe interface is provided on the hydraulic control valve, and the pipe interface is sealed and connected to a safety valve, so that the pressure in the piston chamber 3 and the piston rod chamber 4 can be measured. When the pressure exceeds the set value, the safety valve opens.

[0034] Example 2

[0035] like Figure 1-2 As shown, the utility model provides an internal liquid-filled balancing jack, including a cylinder barrel 1 and a piston rod 2 which are coaxially sleeved, and a piston chamber 3 and a piston rod chamber 4 are formed therebetween. A first liquid channel and a second liquid channel are formed inside the piston rod 2, and the first liquid channel is connected to the piston rod chamber 4, and the second liquid channel is connected to the piston chamber 3.

[0036] The first liquid channel includes an axial section 21 and a plurality of radial sections 22 connecting the axial section 21 and the piston rod chamber 4 . The axial section 21 extends to the protruding end of the piston rod 2 , and all radial sections 22 are located at the same cross section of the axial section 21 .

[0037] The radial section 22 has a plurality of second holes formed on the side wall of the piston rod 2 , and all the second holes are circumferentially and evenly spaced.

[0038] A pipe 23 having a smaller diameter than the axial section 21 is installed in the axial section 21. The axial section 21 and the pipe 23 are coaxially arranged. The pipe 23 is a second liquid channel connected to the piston chamber 3. The pipe 23 has a liquid through hole located at the piston end of the piston rod 2, and the liquid through hole connects the second liquid channel and the piston chamber 3. The radius of the pipe 23 is 0.55-0.65 times the radius of the axial section 21, so that the volume between the axial section 21 and the pipe 23 matches the volume of the pipe 23.

[0039] The axial section 21 has a first hole opened on the piston end of the piston rod 2, and the first hole is provided with an annular plug 211 that seals the first liquid channel and the piston chamber 3 so that the liquid in the piston rod chamber 4 flows back to the extended end of the piston rod 2 in the first liquid channel and the liquid in the first liquid channel can only be supplied to the piston rod chamber 4. At the same time, the annular plug 211 is sleeved on the outside of the pipeline 23 to provide support for the pipeline 23. In order to avoid blocking the flow of liquid in the radial section 22, the axial length of the annular plug 211 is set to be smaller than the distance from the position of the radial section 22 located in the axial section 21 to the first hole.

[0040] In addition, a hydraulically controlled valve (not shown in the figure) is provided at the extended end of the piston rod 2, and a one-way valve is provided on the hydraulically controlled valve, which is sealed and connected to the first liquid channel and the second liquid channel respectively. The hydraulically controlled valve is fixed by bolts. When the piston rod 2 is extended to a specified length, the hydraulically controlled valve is closed to lock the jack.

[0041] At the same time, a pipe interface is provided on the hydraulic control valve, and the pipe interface is sealed and connected to a safety valve (not shown in the figure), so that the pressure in the piston chamber 3 and the piston rod chamber 4 can be measured. When the pressure exceeds the set value, the safety valve opens.

[0042] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a combined manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0043] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An internal liquid-filled balancing jack, comprising a cylinder barrel (1) and a piston rod (2) coaxially arranged, wherein a piston chamber (3) and a piston rod chamber (4) are formed between the cylinder barrel and the piston rod chamber, wherein: A first liquid channel and a second liquid channel are formed inside the piston rod (2), the first liquid channel is in communication with the piston rod chamber (4), and the second liquid channel is in communication with the piston chamber (3); The first liquid channel comprises an axial section (21) and a plurality of radial sections (22) connecting the axial section (21) and the piston rod chamber (4), the axial section (21) extending to the protruding end of the piston rod (2), and all the radial sections (22) being located at the same cross section of the axial section (21); A pipe (23) having a smaller diameter than the axial section (21) is installed in the axial section (21); the axial section (21) and the pipe (23) are coaxially arranged; the pipe (23) is a second liquid channel communicating with the piston chamber (3).

2. The internal liquid-filled balancing jack according to claim 1, characterized in that: The axial section (21) has a first hole opened on the piston end of the piston rod (2), and the first hole is provided with an annular plug (211) that seals the first liquid channel and the piston chamber (3); The annular plug (211) is sleeved on the outside of the pipe (23); The pipeline (23) has a liquid through hole located at the piston end of the piston rod (2), and the liquid through hole is connected with the second liquid channel and the piston chamber (3).

3. The internal liquid-filled balancing jack according to claim 2, characterized in that: The axial length of the annular plug (211) is smaller than the distance from the position of the radial section (22) located in the axial section (21) to the first hole.

4. The internal liquid-filled balancing jack according to claim 1, characterized in that: All the radial segments (22) are distributed symmetrically with respect to the cross section of the axis where the axial segment (21) is located.

5. The internal liquid-filled balancing jack according to claim 1, characterized in that: The radial section (22) has a plurality of second holes opened on the side wall of the piston rod (2), and all the second holes are distributed at equal intervals in the circumferential direction.

6. The internal liquid-filled balancing jack according to claim 1, characterized in that: The radius of the pipe (23) is 0.55-0.65 times the radius of the axial section (21), so that the volume between the axial section (21) and the pipe (23) matches the volume of the pipe (23).

7. The internal liquid-filled balancing jack according to claim 1, characterized in that: The extended end of the piston rod (2) is provided with a hydraulically controlled valve, and the hydraulically controlled valve is provided with a one-way valve which is respectively connected with the first liquid channel and the second liquid channel in a sealed manner.

8. The internal liquid-filled balancing jack according to claim 7, characterized in that: The hydraulic control valve is provided with a pipe interface, and the pipe interface is sealed and connected to a safety valve.

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