A liquid adding gun driving mechanism

Abstract

The utility model discloses a kind of liquid adding gun driving mechanisms, including cylinder barrel, main piston and auxiliary piston are slidably installed in cylinder barrel, the main piston is connected with the driven part, the auxiliary piston is located the other side of main piston, main piston and auxiliary piston will drive cylinder body inside in order to be divided into first chamber, second chamber and third chamber, wherein first chamber is at the side of driving part, the inner diameter of third chamber is less than the inner diameter of first chamber;Unlocking valve and exhaust valve for controlling the air intake or exhaust of first chamber, second chamber and third chamber are installed on the driving cylinder;The utility model can realize the high efficiency, high safety, long life of liquid adding gun by ingenious cylinder design and two control valves.

Description

Technical Field

[0001] This utility model relates to a liquid dispensing gun assembly, specifically a liquid dispensing gun drive mechanism. Background Technology

[0002] The refueling nozzle is a key piece of equipment in liquefied natural gas (LNG) refueling stations. Its function is to enable the rapid and safe connection and disconnection between the refueling pipeline and the receiving tank truck. During the refueling operation, the movement of the nozzle barrel is controlled by a drive mechanism, which causes the valve core inside the nozzle to move relative to the valve, thereby opening or closing the flow channel and completing the refueling.

[0003] To address the aforementioned driving requirements, the applicant has already filed relevant patents. For example, in utility model patent application number 2023236045226, entitled "A Pneumatic Liquid Dispensing Gun," and patent application number 2023236043432, entitled "An LNG Angle-Type Pneumatic Liquid Dispensing Gun," both employ a driving cylinder scheme. This scheme uses an integrated control valve to operate the cylinder. Specifically, the control valve is equipped with a lever, and its operation is designed with two positions: first, when the lever is pulled to the first position, the venting (pressure relief) function is executed; then, when it is pulled further to the second position, the unlocking function is executed.

[0004] While the design intent behind the aforementioned graded operation is clear, it presents significant operational safety hazards in practical applications. Skilled operators, in pursuit of efficiency, are prone to habitually and quickly pulling the lever directly to the second position, skipping the crucial first-position venting step. This "one-step" operation can force the dispensing nozzle to unlock while residual pressure remains in the pipeline, causing it to spring off instantly under internal pressure. This not only risks damaging the equipment but also poses a serious threat to the operator's safety, representing an uncontrollable operational risk. Utility Model Content

[0005] Therefore, in order to overcome the above-mentioned shortcomings, this utility model provides a liquid dispensing gun drive mechanism, which, through a clever cylinder design and two control valves, can achieve high efficiency, high safety and long service life of the liquid dispensing gun.

[0006] Specifically, a liquid dispensing gun drive mechanism includes a cylinder body, in which a main piston and a secondary piston are slidably mounted. The main piston is connected to the driven component (inner gun barrel), and the secondary piston is located on the other side of the main piston. The main piston and the secondary piston divide the cylinder body into a first chamber, a second chamber, and a third chamber in sequence, wherein the first chamber is on the drive component side, and the inner diameter of the third chamber is smaller than the inner diameter of the first chamber. An unlocking valve and an exhaust valve for controlling the intake or exhaust of the first chamber, the second chamber, and the third chamber are installed on the drive cylinder.

[0007] Optionally, the unlocking valve is a two-position three-way valve, and the exhaust valve is a two-position five-way valve.

[0008] Optionally, the unlocking valve is installed on the cylinder body via a first pad, and two air guide holes are provided on the first pad. The two air guide holes are respectively connected to the air passage of the unlocking valve, one of the air guide holes is connected to the third chamber, and the other air guide hole is connected to the first chamber. The exhaust valve is mounted on the cylinder body via a second gasket. Two air guide holes are provided on the second gasket, one of which communicates with the second chamber and the other of which communicates with the first chamber.

[0009] Optionally, the unlocking valve includes an unlocking valve body, which has an air outlet, two vent holes, and an air guide ring groove that matches the air outlet or vent holes. The two vent holes are respectively connected to the two air guide holes of the first pad. An unlocking valve stem is spring-loaded into the unlocking valve body. The unlocking valve stem has a connecting annular groove A, and sealing rings are installed on both sides of the connecting annular groove A. When the unlocking valve stem is not subjected to external force, the two vent holes are not connected under the action of the sealing ring, so the first chamber and the third chamber are disconnected and independent of each other. When the unlocking valve stem is pushed to the stop point by external force, the two vent holes are connected through the connecting ring groove A, so the first chamber and the third chamber are connected through the connecting ring groove A.

[0010] Optionally, the exhaust valve includes an exhaust valve body, which has two vent holes, three air outlet holes arranged in a row, and an air guide ring groove that matches the air outlet holes or vent holes. The two vent holes are respectively connected to the air guide holes on the second pad. The exhaust valve body is equipped with a reciprocating exhaust valve rod that passes through the exhaust valve body and the air guide ring groove. At both ends of the exhaust valve rod are valve handles. The exhaust valve rod has sequentially formed connecting ring grooves B and C. When the exhaust valve rod reaches its stop point at one end, the exhaust port near that stop point is closed by the exhaust valve rod. The middle exhaust port communicates with the first chamber through connecting ring groove B, and the air inlet on the other side communicates with the second chamber through connecting ring groove C. When the exhaust valve rod reaches its stop point on the other side, the exhaust port near that side is closed by the exhaust valve rod. The middle exhaust port communicates with the second chamber through connecting ring groove C, and the air inlet on the other side communicates with the first chamber through connecting ring groove B.

[0011] Optionally, the edge of the air guide ring groove is arc-shaped to reduce friction when the sealing ring enters the air guide ring groove. If the edge of the air guide ring groove is a sharp right angle, the sealing ring will be easily damaged by moving back and forth, thereby reducing the service life of the sealing ring.

[0012] Optionally, the cylinder body is provided with two handles, and the exhaust valve stem of the exhaust valve is located inside the handles, so that the operator can easily control the exhaust valve stem when holding the handles.

[0013] This utility model has the following advantages: This utility model is a liquid dispensing gun drive mechanism, used to drive the inner barrel of the liquid dispensing gun to move axially. Through the design of cylinder and two control valves, the two processes of venting (pressure relief) and unlocking can be executed separately, solving the safety hazard caused by operator misoperation that results in unlocking before venting (or after venting is completed).

[0014] By reasonably modifying the unlocking valve, under normal conditions (without external force), the first and third chambers of the cylinder can be connected via the connecting annular groove A inside the unlocking valve. This connection ensures that the differential circuit cannot be established and venting cannot occur unless a "pressure relief" operation (i.e., pressing the exhaust valve rod) is performed. This structure ensures that the dispensing nozzle can only proceed with subsequent unlocking and nozzle retraction after the operator has consciously performed a pressure relief operation.

[0015] The unlocking valve (two-position three-way) and exhaust valve (two-position five-way) on the cylinder block described in this application are directly connected to each chamber through the air guide hole on the gasket. This integrated design eliminates the need for complex external pipelines, reduces possible leakage points, and makes the structure more compact and reliable.

[0016] The two-position five-way design of the exhaust valve allows for flexible switching between the intake and exhaust of the first and second chambers, thereby precisely controlling the advance and retraction of the inner barrel. This reduces installation space and piping connections, improves system response speed and control accuracy, and lowers the risk of malfunctions due to loose piping.

[0017] Meanwhile, this utility model optimizes the sealing and wear-resistant design, extending service life. The arc-shaped design at the edge of the air guide ring groove in the valve body effectively avoids the cutting and wear of the sealing ring by sharp right angles. This reduces frictional damage to the sealing ring during reciprocating motion, extends the service life of the seal and the entire valve, reduces maintenance frequency and costs, and improves the long-term operational reliability of the equipment.

[0018] Meanwhile, this application places the unlocking valve rod of the unlocking valve inside the cylinder handle. When the operator holds the handle with both hands to move or hold the equipment, their fingers can naturally touch the unlocking valve rod, facilitating convenient mode switching or exhaust operation. This conforms to ergonomic principles and improves the convenience and efficiency of operation. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural schematic diagram of the liquid dispensing gun drive mechanism described in this utility model; Figure 2 This is a schematic diagram of the dispensing gun drive mechanism of the present invention in a disassembled state; Figure 3 This is a cross-sectional schematic diagram of the liquid dispensing gun drive mechanism described in this utility model; Figure 4 This is a test schematic diagram of the liquid dispensing gun drive mechanism described in this utility model; Figure 5 yes Figure 4 Cross-sectional view of AA (with the inner barrel removed). Figure 6 This is a three-dimensional structural diagram of the liquid dispensing gun drive mechanism after the handle is installed; Figure 7 This is a three-dimensional schematic diagram of the exhaust valve described in this utility model; Figure 8 This is a three-dimensional schematic diagram of the exhaust valve described in this utility model from another perspective; Figure 9 This is a cross-sectional view of the exhaust valve described in this utility model; Figure 10 This is a three-dimensional schematic diagram of the unlocking valve described in this utility model; Figure 11 This is a three-dimensional schematic diagram of the unlocking valve described in this utility model from another perspective; Figure 12 This is a cross-sectional view of the unlocking valve described in this utility model; Figure 13 This is a three-dimensional structural diagram of the exhaust valve stem described in this utility model; Figure 14 This is a three-dimensional structural diagram of the unlocking valve stem described in this utility model; In the diagram: 100, cylinder body; 101, first chamber; 102, second chamber; 103, third chamber; 110, main piston; 120, auxiliary piston; 200, exhaust valve; 210, second gasket; 220, valve stem handle B; 230, exhaust valve body; 231, air guide ring groove B; 240, exhaust valve stem; 241, connecting ring groove B; 242, connecting ring groove C; 300, unlocking valve; 310, first gasket; 320, valve stem handle A; 330, unlocking valve body; 331, air guide ring groove A; 340, unlocking valve stem; 341, connecting ring groove A; 342, sealing ring; 343, spring; 400, driven component; 500, handle; 600, exhaust port; 700, vent. Detailed Implementation

[0020] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0021] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0022] As described in the background section, while the design intent of the graded operation is clear, it presents significant operational safety hazards in practical applications. Skilled operators, in pursuit of efficiency, are prone to habitually and quickly pulling the lever directly to the second grade, skipping the crucial first-grade venting step. This "one-step" operation can cause the dispensing nozzle to be forcibly unlocked while residual pressure remains in the pipeline, resulting in it being instantly ejected under internal pressure. This not only risks damaging the equipment but also poses a serious threat to the operator's personal safety, presenting an uncontrollable operational risk.

[0023] For the reasons mentioned above, this embodiment provides a liquid dispensing gun driving mechanism, such as... Figures 1-14 As shown, the device includes a cylinder body 100, in which a main piston 110 and a secondary piston 120 are slidably mounted. The main piston is connected to the driven component 400 (such as the inner barrel of a liquid dispensing gun), and the secondary piston is located on the other side of the main piston. The main piston and the secondary piston divide the cylinder body of the driving cylinder into a first chamber 101, a second chamber 102, and a third chamber 103 in sequence. The first chamber is on the driving component side, and the inner diameter of the third chamber is smaller than the inner diameter of the first chamber. An unlocking valve 300 and an exhaust valve 200 for controlling the intake or exhaust of air into the first, second, and third chambers are installed on the drive cylinder. The unlocking valve 300 is a two-position three-way valve, and the exhaust valve 200 is a two-position five-way valve.

[0024] For example, the unlocking valve 300 is installed on the cylinder body 100 via a first pad 310. Two air guide holes are provided on the first pad, and the two air guide holes are respectively connected to the air passage of the unlocking valve. One air guide hole is connected to the third chamber, and the other air exhaust valve is connected to the first chamber. The exhaust valve 200 is installed on the cylinder body via a second gasket 210. Two air guide holes are provided on the second gasket, one of which communicates with the second chamber and the other of which communicates with the first chamber.

[0025] For example, the unlocking valve 300 includes an unlocking valve body 330, which has an air outlet 700, two vent holes 700, and a guide ring groove A331 that matches the air outlet or vent hole. The two vent holes are respectively connected to the two guide holes of the first pad. An unlocking valve stem 340 is installed inside the unlocking valve body 330 via a spring 343. A valve stem handle A320 is installed near the spring end of the unlocking valve stem. A connecting ring groove A341 matching the air guide ring groove is provided on the unlocking valve stem. Sealing rings 342 are installed on both sides of the connecting ring groove A341. When the unlocking valve stem is not subjected to external force, the two vent holes are not connected under the action of the sealing rings, so the first chamber and the third chamber are disconnected and independent of each other. When the unlocking valve stem is pushed to the stop point by external force, the two vent holes are connected through the connecting ring groove A, so the first chamber and the third chamber are connected through the connecting ring groove A.

[0026] For example, the exhaust valve 200 includes an exhaust valve body 230, which has two vent holes 700, three air outlet holes 600 arranged in a row, and two air guide ring grooves B231 that match the air outlet holes or vent holes. The two vent holes are respectively connected to the air guide holes on the second pad. An exhaust valve stem 240 that can reciprocate is installed inside the exhaust valve body 230. The exhaust valve stem passes through the exhaust valve body and the air guide ring groove. At both ends of the exhaust valve stem are valve stem handles B220. The exhaust valve stem has connecting ring grooves B241 and C242 in sequence. When the exhaust valve stem reaches the stop point at one end, the exhaust valve stem closes the exhaust port on the side near the stop point. The middle exhaust port is connected to the first chamber through the connecting ring groove B, and the air inlet on the other side is connected to the second chamber through the connecting ring groove C. When the exhaust valve stem reaches the stop point on the other side, the exhaust valve stem closes the exhaust port on that side. The middle exhaust port is connected to the second chamber through the connecting ring groove C, and the air inlet on the other side is connected to the first chamber through the connecting ring groove B.

[0027] The aforementioned technical features enable axial movement of the inner barrel (i.e., the driven component) of the dispensing gun. Through the design of the cylinder and two control valves, the venting (pressure relief) and unlocking processes can be executed separately, resolving the safety hazard caused by operator error leading to unlocking before venting (or before venting is complete). With reasonable improvements to the unlocking valve, under normal conditions (without external force), the first and third chambers of the cylinder can be connected via a connecting annular groove A inside the unlocking valve. This connection ensures that the differential circuit cannot be established and venting cannot occur unless the "pressure relief" operation (i.e., pressing the venting valve rod) is performed. This structure ensures that the dispensing gun can only proceed to the subsequent unlocking and gun retraction stage after the operator consciously performs a pressure relief operation.

[0028] When the liquid dispensing gun needs to be unlocked (when the chucks separate), pressure must first be released. The first and third chambers are connected through the unlocking valve. Under the control of the exhaust valve, the second chamber is vented, while either the first or third chamber is vented (since the first and third chambers are connected in this state, venting to either chamber is the same). Because the inner diameter of the third chamber is larger than that of the first chamber, or the working area of ​​the auxiliary piston on the third chamber side is larger than that of the main piston on the first chamber side, under the same gas pressure in the third and first chambers, the auxiliary piston moves to the stop point closer to the main piston. After the pressure is released, the first and third chambers are made independent by controlling the unlocking valve (releasing the unlocking valve rod, which is then reset by the spring). Under the action of the exhaust valve, the first chamber is continuously vented, and the third chamber is vented, thus pushing the main and auxiliary pistons to the rear stop point. As the main piston continues to move backward, it drives the inner barrel to move backward, which provides the driving force for the chucks to separate.

[0029] To improve the service life of the sealing ring, the edge of the air guide ring groove (air guide ring groove A or air guide ring groove B) is arc-shaped to reduce friction when the sealing ring enters the air guide ring groove. If the edge of the air guide ring groove (air guide ring groove A or air guide ring groove B) is a sharp right angle, the sealing ring will be easily damaged by moving back and forth, thereby reducing the service life of the sealing ring.

[0030] To facilitate the operation of the unlocking valve, in one embodiment, such as Figure 6 As shown, the cylinder body is provided with two handles 500, and the unlocking valve rod of the unlocking valve is located inside the handle, so that the operator can easily control the unlocking valve rod when holding the handle.

[0031] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A liquid dispensing nozzle driving mechanism, characterized in that: The cylinder includes a cylinder body, in which a main piston and a secondary piston are slidably mounted. The main piston is connected to the driven component, and the secondary piston is located on the other side of the main piston. The main piston and the secondary piston divide the cylinder body of the driving cylinder into a first chamber, a second chamber and a third chamber in sequence, wherein the first chamber is on the driving component side, and the inner diameter of the third chamber is smaller than the inner diameter of the first chamber. An unlocking valve and an exhaust valve for controlling the intake or exhaust of the first chamber, the second chamber, and the third chamber are installed on the drive cylinder.

2. The liquid dispensing gun driving mechanism according to claim 1, characterized in that: The unlocking valve is a two-position three-way valve, and the exhaust valve is a two-position five-way valve.

3. The liquid dispensing nozzle driving mechanism according to claim 1, characterized in that: The unlocking valve is installed on the cylinder body via a first pad. Two air guide holes are provided on the first pad. The two air guide holes are respectively connected to the air passage of the unlocking valve. One air guide hole is connected to the third chamber, and the other air guide hole is connected to the first chamber. The exhaust valve is mounted on the cylinder body via a second gasket. Two air guide holes are provided on the second gasket, one of which communicates with the second chamber and the other of which communicates with the first chamber.

4. The liquid dispensing nozzle driving mechanism according to claim 3, characterized in that: The unlocking valve includes an unlocking valve body, which has an air outlet, two vent holes, and a guide ring groove that matches the air outlet or vent holes. The two vent holes are respectively connected to the two guide holes of the first pad. An unlocking valve stem is spring-loaded within the unlocking valve body. The unlocking valve stem has a connecting annular groove A, and sealing rings are installed on both sides of the connecting annular groove A. When the unlocking valve stem is not subjected to external force, the two vent holes are not connected under the action of the sealing rings, so the first chamber and the third chamber are disconnected and independent of each other. When the unlocking valve stem is pushed to the stop point by external force, the two vent holes are connected through the connecting annular groove A, so the first chamber and the third chamber are connected through the connecting annular groove A.

5. The liquid dispensing gun driving mechanism according to claim 3, characterized in that: The exhaust valve includes an exhaust valve body, which has two vent holes, three air outlet holes arranged in a row, and air guide ring grooves that match the air outlet holes or vent holes. The two vent holes are respectively connected to the air guide holes on the second pad. The exhaust valve body is equipped with a reciprocating exhaust valve rod that passes through the exhaust valve body and the air guide ring groove. At both ends of the exhaust valve rod are valve handles. The exhaust valve rod has sequentially formed connecting ring grooves B and C. When the exhaust valve rod reaches its stop point at one end, the exhaust port near that stop point is closed by the exhaust valve rod. The middle exhaust port communicates with the first chamber through connecting ring groove B, and the air inlet on the other side communicates with the second chamber through connecting ring groove C. When the exhaust valve rod reaches its stop point on the other side, the exhaust port near that side is closed by the exhaust valve rod. The middle exhaust port communicates with the second chamber through connecting ring groove C, and the air inlet on the other side communicates with the first chamber through connecting ring groove B.

6. The liquid dispensing gun driving mechanism according to claim 4 or 5, characterized in that: The edge of the air guide ring groove is arc-shaped.

7. The liquid dispensing gun driving mechanism according to claim 1, characterized in that: The cylinder body is equipped with two handles, and the unlocking valve stem of the unlocking valve is located inside the handle.

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