A hydraulic rock drill accumulator charging connector structure

Abstract

This utility model discloses a hydraulic rock drill accumulator air charging connector structure, relating to the field of engineering machinery technology. The structure includes: a connecting pipe assembly with a double sealing component, comprising an annular sealing ring and a U-shaped sealing ring; a safety valve assembly, comprising a valve body, a conical valve seat, and a rupture disc, the valve body containing a pressure chamber and a pressure relief chamber, the rupture disc and the conical valve seat being disposed within the valve body; and an air charging pipe assembly, comprising an air charging pipe body, a spring seat, a first spring, and a one-way valve core, the air charging pipe body being connected to the valve body, and the spring seat being fixedly disposed within the air charging pipe body. The air charging pipe assembly, safety valve assembly, and connecting pipe assembly are coaxially connected sequentially, and their internal components are interconnected to form an air intake passage. This utility model is installed at the top of the hydraulic rock drill accumulator, with the other end connected to an external air source. It achieves air charging through the internally interconnected air intake passage while simultaneously ensuring airtightness and pressure relief capability through the double sealing component and safety valve assembly.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, and in particular to a structure for an air charging connector for a hydraulic rock drill accumulator. Background Technology

[0002] Accumulators are an important component of hydraulic rock drills, primarily used for storing energy, stabilizing oil pressure, eliminating pulses, and reducing noise. The working principle of an accumulator is based on the compressibility of gas, converting energy in the system into compressible energy or potential energy. When the system needs it, the compressed energy or potential energy is converted back into hydraulic or pneumatic pressure to replenish the system. Therefore, accumulators need to be charged internally during actual use. In existing technology, operators inject external air into the accumulator through an air charging connector.

[0003] However, existing air inflators have the following technical defects: most existing air inflators use single-stage sealing rings, which are prone to permanent deformation or extrusion damage when the pressure fluctuates frequently in the system, and cannot compensate for the threaded connection gap, resulting in gas leakage along the thread gap; existing air inflators generally do not integrate safety pressure relief devices, and when the gas in the accumulator becomes abnormally pressurized due to factors such as temperature rise or misoperation, they only rely on the system's main safety valve to respond, which poses a risk of pressure relief lag.

[0004] Therefore, there is a need for a hydraulic rock drill accumulator air charging joint structure with good airtightness and safe pressure relief capability. Utility Model Content

[0005] The main purpose of this utility model is to provide a hydraulic rock drill accumulator air charging joint structure, which aims to solve the problems of insufficient air tightness and lack of pressure relief capability of existing air charging joints.

[0006] To achieve the above objectives, the present invention proposes a hydraulic rock drill accumulator charging connector structure, which is applied to the accumulator and includes:

[0007] A connecting pipe assembly is provided with a double sealing assembly at one end near the accumulator. The double sealing assembly includes an annular sealing ring and a U-shaped sealing ring. Both the annular sealing ring and the U-shaped sealing ring are fixedly connected to the annular groove on the outer wall of the connecting pipe. The U-shaped sealing ring is disposed on the side of the annular sealing ring near the accumulator.

[0008] A safety valve assembly is connected to the end of the connecting pipe assembly away from the accumulator. The safety valve assembly includes a valve body, a conical valve seat, and a rupture disc. The valve body has a pressure chamber along its axis and a pressure relief chamber along its radial direction. The pressure relief chamber communicates with the external environment through a pressure relief hole on the outer wall of the valve body. The rupture disc is disposed at the communication point between the pressure chamber and the pressure relief chamber via a pressure ring. The axis of the rupture disc is perpendicular to the pressure chamber. The conical valve seat is fixedly disposed at the end of the valve body away from the connecting pipe assembly and is coaxial with the valve body. The conical valve seat has a through hole along its axial direction.

[0009] An inflation tube assembly includes an inflation tube body, a spring seat, a first spring, and a one-way valve core. The inflation tube body is connected to the end of the valve body away from the accumulator. The spring seat is fixedly disposed in the end of the inflation tube body away from the accumulator. One end of the one-way valve core is movably connected to the spring seat through the first spring. The other end of the one-way valve core passes through the valve body and is connected to the conical valve seat.

[0010] The inflation tube assembly, safety valve assembly, and connecting tube assembly are coaxially connected in sequence, and the three are internally interconnected to form an air intake passage.

[0011] Preferably, the pressure chamber is a venturi tube structure, and the pressure chamber has a constriction section, a throat, and a diffuser section connected in sequence. The throat has a through hole, and the pressure chamber is connected to the pressure relief chamber through the through hole. The rupture disc is covered by the through hole. The constriction section is located in the pressure chamber near one end of the inflation tube assembly, and the diffuser section is connected to the connecting tube assembly.

[0012] Preferably, the safety valve assembly further includes a side valve seat, a positioning ring, a pressure valve disc, and a side pressure spring. The side valve seat is arranged radially along the throat, and the axis of the side valve seat is coaxial with the axis of the pressure relief chamber. The side valve seat also has a central hole, which is coaxially connected to the through hole. A positioning ring is also provided on the side of the side valve seat near the pressure relief chamber. The pressure valve disc is a U-shaped disc, and one end of the pressure valve disc abuts against the positioning ring. A receiving space is formed between the pressure valve disc and the positioning ring. The rupture disc is disposed in the receiving space. The other end of the pressure valve disc is movably connected to the valve body through the side pressure spring.

[0013] Preferably, the contraction angle α1 of the contraction section is 20°±2°, the diffusion angle α2 of the diffusion section is 7°±1°, and the ratio of the diameter D2 of the throat to the diameter D1 of the inlet of the contraction section is 1:2.5~1:3.

[0014] Preferably, the rupture disc is a circular flat diaphragm, and a cross-shaped groove is provided on the side of the rupture disc facing the pressure chamber, with a guide hole at the center of the cross-shaped groove.

[0015] Preferably, the inflation tube assembly is further provided with a quick-connect interface and an air inlet pipe. The quick-connect interface is located on the end of the inflation tube body away from the accumulator. The quick-connect interface is sleeved on the air inlet pipe. The inner wall of the quick-connect interface is provided with a guide slope that is set at an angle to the axis of the air inlet pipe.

[0016] Preferably, the connecting pipe assembly includes a connecting pipe body and an annular groove. One end of the outer wall of the connecting pipe body is provided with a threaded connecting section. The annular groove is formed on the outer wall of the connecting pipe body and connected to the threaded connecting section. The U-shaped sealing ring is disposed on the side of the annular sealing ring near the energy storage device.

[0017] The hydraulic rock drill accumulator charging connector structure of this utility model is connected to the accumulator through a connecting pipe assembly. During connection, it is sealed to the accumulator through a double sealing assembly. The top of the connecting pipe assembly is connected in sequence to a safety valve assembly and a charging pipe assembly, and the three are connected by an air intake passage. During normal charging, the airflow enters the accumulator through the air intake passage, and the charging has a good airtight effect. When the accumulator is overpressurized, the one-way valve core and the conical valve seat are pushed upward by the air pressure to form a seal. After the airflow breaks the rupture disc, it is discharged outward through the pressure relief hole to achieve safe pressure relief. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a cross-sectional schematic diagram of the air charging connector structure of the accumulator of a hydraulic rock drill according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the air charging connector structure of the accumulator of a hydraulic rock drill according to an embodiment of the present invention;

[0021] Figure 3 for Figure 1 Enlarged structural diagram at point A;

[0022] Figure 4 This is a schematic diagram of the structure of a rupture disc according to an embodiment of the present invention.

[0023] Explanation of icon numbers:

[0024] label name label name 1000 Hydraulic rock drill accumulator air charging joint structure 100 Connecting pipe assembly 110 Double sealing assembly 111 Annular sealing ring 112 U-shaped sealing ring 120 Connecting pipe body 200 Safety valve assembly 210 Valve body 211 pressure chamber 212 Pressure relief chamber 220 Conical valve seat 230 Explosive fragments 231 guide hole 240 Side valve seat 250 Positioning ring 260 Pressure valve disc 270 Side compression spring 300 Inflation tube assembly 310 Inflation tube 320 Spring seat 330 First spring 340 One-way valve core 350 quick-connect interface 360 intake manifold

[0025] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] It should be noted that all directional indicators in this embodiment are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0028] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0029] In the existing technology, the accumulator charging connector structure has problems such as insufficient coupling and non-modular design of the charging-depressurization function, which makes it difficult to achieve structural integration and coordinated control. Furthermore, the dynamic response is sluggish, the external safety valve is far from the gas chamber of the accumulator, and the pressure transmission delay causes the depressurization action to be delayed, making it impossible to simultaneously meet the requirements of sealing reliability and accurate depressurization.

[0030] Based on this, such as Figures 1-4As shown, this utility model proposes a hydraulic rock drill accumulator charging connector structure 1000 for use in hydraulic rock drill accumulators, including: a connecting pipe assembly 100, with a double sealing assembly 110 at one end of the connecting pipe assembly 100 near the accumulator. The double sealing assembly 110 includes an annular sealing ring 111 and a U-shaped sealing ring 112, both of which are fixedly connected to an annular groove on the outer wall of the connecting pipe. The U-shaped sealing ring 112 is disposed in the annular groove. The sealing ring 111 is located on the side near the accumulator; the safety valve assembly 200 is connected to the end of the connecting pipe assembly 100 away from the accumulator. The safety valve assembly 200 includes a valve body 210, a conical valve seat 220, and a rupture disc 230. The valve body 210 has a pressure chamber 211 along the axis and a pressure relief chamber 212 along the radial direction. The pressure relief chamber 212 communicates with the external environment through a pressure relief hole provided on the outer wall of the valve body 210. The rupture disc 230 communicates with the external environment through a pressure relief hole provided on the outer wall of the valve body 210. An overpressure ring is located at the connection between pressure chamber 211 and pressure relief chamber 212. The axis of the rupture disc 230 is perpendicular to pressure chamber 211. A conical valve seat 220 is fixedly located inside valve body 210 at the end away from connecting pipe assembly 100 and coaxial with valve body 210. A through hole is formed in the conical valve seat 220 along the axial direction. An inflation pipe assembly 300 includes an inflation pipe body 310, a spring seat 320, a first spring 330, and a one-way valve core 340. The inflation pipe body 310 and... The valve body 210 is connected to the end away from the accumulator, and the spring seat 320 is fixedly installed inside the inflation tube 310 at the end away from the accumulator. One end of the one-way valve core 340 is movably connected to the spring seat 320 through the first spring 330, and the other end of the one-way valve core 340 passes through the valve body 210 and is connected to the conical valve seat 220. The inflation tube assembly 300, the safety valve assembly 200, and the connecting tube assembly 100 are coaxially connected in sequence, and the three are internally connected to form an air intake passage.

[0031] In this embodiment, the inflation pipe assembly 300, the safety valve assembly 200, and the connecting pipe assembly 100 are connected sequentially from top to bottom. The three are internally interconnected to form an air intake passage, through which an external air source enters the accumulator. A pressure chamber 211 is provided within the valve body 210 of the safety valve assembly 200, and a pressure relief chamber 212 is also provided circumferentially around the pressure chamber 211. The pressure relief chamber 212 communicates with the external environment through a pressure relief hole. During normal air intake, the one-way valve core 340 is separated from the conical valve seat 220 by the thrust of the first spring 330, and the airflow flows normally into the accumulator. The pressure relief chamber 212 and the pressure chamber 211 inside the safety valve assembly 200 are isolated by the rupture disc 230 under normal conditions. When the accumulator is overpressurized, the gas in the accumulator is ejected upwards. The gas pressure is greater than the thrust of the first spring 330 on the one-way valve core 340, causing the one-way valve core 340 to abut against the conical valve seat 220, forming a seal in the pressure chamber 211. The gas then passes through the rupture disc 230, allowing the overpressurized gas to enter the pressure relief chamber 212 and then be discharged through the pressure relief hole.

[0032] In one embodiment, the pressure chamber 211 is a venturi tube structure. The pressure chamber 211 has a constriction section, a throat, and a diffuser section connected in sequence. The throat has a through hole. The pressure chamber 211 is connected to the pressure relief chamber 212 through the through hole. The rupture disc 230 is covered by the through hole. The constriction section is located inside the pressure chamber 211 near one end of the inflation tube assembly 300. The diffuser section is connected to the connecting tube assembly 100.

[0033] In this embodiment, when the gas flows through the throat of the venturi tube, the increased flow velocity and decreased static pressure create a local low-pressure zone, which does not affect the rupture disc 230 located there and prevents gas leakage from there. When the system is overpressured, the pressure difference change at the throat can help trigger the rupture disc 230 to rupture, reduce the action pressure deviation of the rupture disc 230, and shorten the overpressure response time.

[0034] In one embodiment, the safety valve assembly 200 further includes a side valve seat 240, a positioning ring 250, a pressure valve disc 260, and a side pressure spring 270. The side valve seat 240 is arranged radially along the throat and its axis is coaxial with the axis of the pressure relief chamber 212. The side valve seat 240 is also provided with a central hole, which is coaxially connected with a through hole. A positioning ring 250 is also provided on the side of the side valve seat 240 near the pressure relief chamber 212. The pressure valve disc 260 is a U-shaped disc. One end of the pressure valve disc 260 abuts against the positioning ring 250, and a receiving space is formed between the pressure valve disc 260 and the positioning ring 250. A rupture disc 230 is disposed in the receiving space. The other end of the pressure valve disc 260 is movably connected to the valve body 210 through the side pressure spring 270.

[0035] In this embodiment, the positioning ring 250 is arranged circumferentially along the side valve seat 240, and the side pressure spring 270 is arranged on the inner wall of the valve body 210 along the axis of the side valve seat 240. The other end of the side pressure spring 270 is connected to the pressure valve disc 260. Under normal conditions, the pressure valve disc 260 abuts against the positioning ring 250 due to the thrust of the side pressure spring 270. The pressure valve disc 260 is U-shaped, and the opening of the pressure valve disc 260 faces the central hole of the side valve seat 240. Therefore, when the pressure valve disc 260 abuts against the side valve seat 240, it forms a receiving space, and the rupture disc 230 is disposed in this receiving space. When the accumulator is overpressurized, the air pressure ruptures the rupture disc 230 and pushes the pressure valve disc 260, causing it to separate from the positioning ring 250, and the airflow is discharged outward from the pressure relief hole.

[0036] In one embodiment, the contraction angle α1 of the contraction section is 20°±2°, the diffusion angle α2 of the diffusion section is 7°±1°, and the ratio of the diameter D2 of the throat to the diameter D1 at the entrance of the contraction section is 1:2.5~1:3.

[0037] In this embodiment, by designing the contraction angle to be greater than the diffusion angle, flow separation in the diffusion section can be avoided, ensuring a stable flow field during normal inflation. The ratio of the throat diameter to the diameter at the inlet of the contraction section is limited so that the throat flow velocity reaches 2.5-3 times the inflation flow velocity, providing sufficient differential pressure to trigger under overpressure.

[0038] In one embodiment, the rupture disc 230 is a circular flat diaphragm, and a cross-shaped groove is provided on the side of the rupture disc 230 facing the pressure chamber 211, with a guide hole 231 provided at the center of the cross-shaped groove.

[0039] In this embodiment, under normal conditions, the edge of the rupture disc 230 is pressed against the side valve seat 240 by the spring preload of the pressure ring and the side pressure spring 270, and the central area of ​​the rupture disc 230 is suspended, forming a metal hard seal to isolate the pressure chamber 211 from the pressure relief chamber 212. When there is overpressure, the air pressure pushes the one-way valve core 340 to abut against the conical valve seat 220, and the pressure chamber 211 becomes a short-term sealed chamber. The internal pressure increases, and the air pressure bursts the rupture disc 230 through the guide hole 231. The rupture disc 230 is directionally positioned and broken through the cross-shaped groove on its surface. After the overpressure airflow breaks through the rupture disc 230, it is depressurized to the external environment through the pressure relief hole, thus achieving safe depressurization.

[0040] In one embodiment, the inflation tube assembly 300 is further provided with a quick-connect interface 350 and an air inlet tube 360. The quick-connect interface 350 is disposed on the end of the inflation tube body 310 away from the accumulator. The quick-connect interface 350 is sleeved on the air inlet tube 360. The inner wall of the quick-connect interface 350 is provided with a guide slope that is set at an angle to the axis of the air inlet tube 360.

[0041] In this embodiment, the quick-connect interface 350 is an annular structure formed by multiple trapezoidal blocks. There are expansion joints between the multiple trapezoidal blocks to avoid material fatigue caused by long-term inflation. The trapezoidal blocks are provided with guide slopes facing the air inlet pipe 360 ​​located in the center, so that the operator can easily put the air guide hose of the external air source on the top of the air inlet pipe 360. The guide slope is at an angle of 30°±2° with the axis of the air inlet pipe 360 ​​to guide the air guide hose of the external air source to connect with the air inlet pipe 360.

[0042] In one embodiment, the connecting pipe assembly 100 includes a connecting pipe body 120. One end of the outer wall of the connecting pipe body 120 is provided with a threaded connecting section and an annular groove. The annular groove is formed on the outer wall of the connecting pipe body 120 and connected to the threaded connecting section. A U-shaped sealing ring 112 is disposed on the side of the annular sealing ring 111 near the accumulator.

[0043] In this embodiment, the threaded connection section is used to connect to the top of the accumulator. The annular sealing ring 111 and the U-shaped sealing ring 112 are connected sequentially from top to bottom. The annular sealing ring 111 is made of copper alloy with a thickness of 5mm, and the U-shaped sealing ring 112 is made of polyurethane. The bottom of the U-shaped sealing ring 112 is tightly attached to the threaded connection section. During normal air intake, the annular sealing ring 111 and the U-shaped sealing ring 112 can block and seal any gas leakage at the thread, increasing airtightness. When the accumulator is overpressurized, the U-shaped sealing ring 112 can be automatically torn apart by the overpressurized gas, and the gas leaks outward from the gap between the annular sealing ring 111 and the U-shaped sealing ring 112, ensuring safe pressure relief.

[0044] This utility model discloses a hydraulic rock drill accumulator charging connector structure that connects to the accumulator via a connecting pipe assembly. During connection, an annular sealing ring and a U-shaped sealing ring enhance the accumulator's sealing effect during air intake. A safety valve assembly and a charging pipe assembly are sequentially connected to the top of the connecting pipe assembly, and all three are internally connected by an air intake passage. During normal charging, airflow enters the accumulator through the air intake passage, ensuring good airtightness. When the accumulator experiences overpressure, the one-way valve core and the conical valve seat are pushed upwards by the air pressure to form a seal. The airflow ruptures and bursts through the pressure relief hole, while the U-shaped sealing ring ruptures due to the impact of the high-pressure airflow, further assisting in pressure relief and achieving rapid, precise, and safe pressure release.

[0045] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the concept of the present utility model and using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present utility model.

Claims

1. A hydraulic rock drill accumulator charging connection structure, characterized in that, Applications in energy storage devices include: A connecting pipe assembly includes a connecting pipe body. A double sealing assembly is provided at one end of the connecting pipe body near the accumulator. The double sealing assembly includes an annular sealing ring and a U-shaped sealing ring. Both the annular sealing ring and the U-shaped sealing ring are fixedly connected to the outer wall of the connecting pipe body. The U-shaped sealing ring is disposed on the side of the annular sealing ring near the accumulator. A safety valve assembly is connected to the end of the connecting pipe assembly away from the accumulator. The safety valve assembly includes a valve body, a conical valve seat, and a rupture disc. The valve body has a pressure chamber along its axis and a pressure relief chamber along its radial direction. The pressure relief chamber communicates with the external environment through a pressure relief hole on the outer wall of the valve body. The rupture disc is disposed at the communication point between the pressure chamber and the pressure relief chamber via a pressure ring. The axis of the rupture disc is perpendicular to the pressure chamber. The conical valve seat is fixedly disposed at the end of the valve body away from the connecting pipe assembly and is coaxial with the valve body. The conical valve seat has a through hole along its axial direction. An inflation tube assembly includes an inflation tube body, a spring seat, a first spring, and a one-way valve core. The inflation tube body is connected to the end of the valve body away from the accumulator. The spring seat is fixedly disposed in the end of the inflation tube body away from the accumulator. One end of the one-way valve core is movably connected to the spring seat through the first spring. The other end of the one-way valve core passes through the valve body and is connected to the conical valve seat. The inflation tube assembly, safety valve assembly, and connecting tube assembly are coaxially connected in sequence, and the three are internally interconnected to form an air intake passage.

2. The hydraulic rock drill accumulator charging connection structure as claimed in claim 1, characterized in that, The pressure chamber is a venturi tube structure, and the pressure chamber has a constriction section, a throat, and a diffuser section connected in sequence. The throat has a through hole, and the pressure chamber is connected to the pressure relief chamber through the through hole. The rupture disc is covered by the through hole. The constriction section is located in the pressure chamber near one end of the inflation tube assembly, and the diffuser section is connected to the connecting tube assembly.

3. The hydraulic rock drill accumulator charging connection structure as claimed in claim 2, characterized in that, The safety valve assembly further includes a side valve seat, a positioning ring, a pressure valve disc, and a side pressure spring. The side valve seat is arranged radially along the throat, and the axis of the side valve seat is coaxial with the axis of the pressure relief chamber. The side valve seat also has a central hole, which is coaxially connected to the through hole. A positioning ring is also provided on the side valve seat near the pressure relief chamber. The pressure valve disc is a U-shaped disc, and one end of the pressure valve disc abuts against the positioning ring, forming a receiving space between the pressure valve disc and the positioning ring. The rupture disc is disposed in the receiving space, and the other end of the pressure valve disc is movably connected to the valve body through the side pressure spring.

4. The air charging connector structure for the accumulator of a hydraulic rock drill as described in claim 3, characterized in that, The contraction angle α1 of the contraction section is 20°±2°, the diffusion angle α2 of the diffusion section is 7°±1°, and the ratio of the diameter D2 of the throat to the diameter D1 of the inlet of the contraction section is 1:2.5~1:

3.

5. The air charging connector structure for the accumulator of a hydraulic rock drill as described in claim 4, characterized in that, The rupture disc is a circular flat diaphragm, and a cross-shaped groove is provided on the side of the rupture disc facing the pressure chamber, with a guide hole at the center of the cross-shaped groove.

6. The air charging connector structure for the accumulator of a hydraulic rock drill as described in claim 1, characterized in that, The inflation tube assembly is further provided with a quick-connect interface and an air inlet pipe. The quick-connect interface is located on the end of the inflation tube body away from the accumulator. The quick-connect interface is sleeved on the air inlet pipe. The inner wall of the quick-connect interface is provided with a guide slope that is set at an angle to the axis of the air inlet pipe.

7. The air charging connector structure for the accumulator of a hydraulic rock drill as described in claim 1, characterized in that, The outer wall of the connecting pipe is provided with a threaded connecting section and an annular groove. The threaded connecting section is located on one end of the connecting pipe near the accumulator. The annular groove is opened on the outer wall of the connecting pipe and connected to the threaded connecting section. The U-shaped sealing ring is located on the side of the annular sealing ring near the accumulator.

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