A pneumatically controlled normally closed hose clamping device and control method

Abstract

This application discloses a pneumatically controlled normally closed hose clamping device and control method. The device includes: a valve body with a channel for the hose to pass through; opposing pads and rigid pressure blocks, fixed inside the valve body and located on both sides of the channel; a cylinder installed on the outside of the valve body, with its piston rod extending into the valve body and connecting to the pressure blocks; a return spring sleeved on the piston rod and abutting against the inner wall of the valve body and the pressure blocks; a pneumatic control switch connecting the air source and the cylinder inlet; and at least one one-way throttle valve installed at the cylinder exhaust port. When the air source is disconnected or the switch is in the first state, the cylinder depressurizes, and the spring drives the pressure block to press against the pad, clamping the hose; when the switch is in the second state, the cylinder intakes air to overcome the spring force, the pressure block moves away from the pad, and the hose flows. The one-way throttle valve achieves rapid opening by quickly venting air through the one-way valve during intake and slow closing by slowly venting air through the throttle orifice during exhaust, effectively suppressing water hammer. This device has a compact structure, low cost, and combines normally closed safety with adjustable speed.

Description

Technical Field

[0001] This invention belongs to the field of fluid control technology, and particularly relates to a pneumatically controlled normally closed hose clamping device and control method. Background Technology

[0002] In fields such as medical infusion, chemical analysis, food filling, and industrial automation, it is often necessary to control the flow of fluid within flexible tubing. Traditional manual clamps cannot achieve remote control; electric clamp valves are complex in structure and pose electrical safety hazards. Existing pneumatic clamp valves are mostly normally open, meaning they clamp when air is supplied and open when air supply is cut off. If the air supply is unexpectedly interrupted, the valve automatically opens, failing to meet the air failure safety requirements. A few normally closed solutions use double-acting cylinders or complex linkage mechanisms to achieve air failure closure, but their structures are cumbersome, have many parts, are costly, and have fixed opening and closing speeds, making them unsuitable for different fluids requiring water hammer suppression. Therefore, existing technologies struggle to simultaneously meet the three core requirements of normally closed failure safety, compact structure, and adjustable speed. Summary of the Invention

[0003] (a) Purpose of the invention To overcome the above shortcomings, the present invention aims to provide a pneumatically controlled normally closed hose clamping device and control method to solve the technical problems that existing pneumatic clamping valves cannot simultaneously achieve a normally closed function with air loss safety, a simple structure, and adjustable speed.

[0004] (II) Technical Solution To achieve the above objectives, the technical solution provided in this application is as follows: A pneumatically controlled normally closed hose clamping device includes: a valve body with a channel for the hose to pass through; a fixed opposing pad and a movable rigid pressure block inside the valve body, the opposing pad and the rigid pressure block being disposed opposite each other on both sides of the channel; a cylinder mounted on the outside of the valve body, the piston rod of the cylinder extending into the valve body and connected to the rigid pressure block; a return spring sleeved on the piston rod with its two ends abutting against the inner wall of the valve body and the rigid pressure block respectively; a pneumatic control switch connected between the air source and the air inlet of the cylinder for controlling the air intake and exhaust of the cylinder; and at least one one-way throttle valve mounted at the exhaust port of the cylinder; wherein, when the air source is disconnected or the pneumatic control switch is in a first state, the cylinder depressurizes, and the return spring drives the rigid pressure block to move towards the opposing pad, thus cutting off the hose flow; when the pneumatic control switch is in a second state, the cylinder intakes air and overcomes the spring force of the return spring, causing the rigid pressure block to move away from the opposing pad, thus allowing the hose to flow; the one-way throttle valve is used to adjust the moving speed of the rigid pressure block.

[0005] The system employs a return spring to push a rigid pressure block against an opposing pad, achieving normally closed flow interruption. When the air supply is connected, air enters the cylinder, overcoming the spring force and pulling the pressure block away from the hose, allowing flow. If the air supply is interrupted or the switch resets, the spring immediately resets to close the valve, ensuring safety in case of air loss. Simultaneously, a one-way throttle valve is connected in series at the cylinder exhaust port: during intake, the existing gas in the cylinder is quickly discharged through the one-way valve, unimpeded by the piston's upward movement, thus achieving rapid opening; during exhaust, the air supply is cut off, and the compressed gas in the cylinder can only be discharged slowly through the throttle orifice, causing the piston to slowly descend under the spring force, thus achieving slow closing. The pressure block's backpressure speed can be independently controlled by adjusting the throttle orifice diameter, effectively suppressing water hammer impact in the pipeline. The entire device requires only a single cylinder, a single spring, and a simple pneumatic switch, without complex linkage mechanisms. It has a compact structure, few parts, and low cost, and supports remote pneumatic control and speed adjustment, solving the core problems of existing technologies that cannot simultaneously achieve normally closed safety, a simple structure, and adjustable speed.

[0006] In some embodiments, the pneumatic control switch is a manual pneumatic push-button valve or an electro-optical solenoid pilot valve, wherein the electro-optical solenoid pilot valve is used to receive remote control signals to control the intake and exhaust of the cylinder.

[0007] The manual push-button valve is installed on the outer wall of the valve body. Under normal conditions, the cylinder is depressurized by venting to the atmosphere. Pressing the button allows air to enter the cylinder for local control. The electrically controlled solenoid pilot valve is connected to a PLC or a remote button, and the cylinder's air intake and exhaust are remotely controlled by on / off electrical signals, enabling automated production lines or centralized linkage of multiple devices. These two options flexibly adapt to different scenarios, retaining the simplicity of manual operation while expanding remote control capabilities, allowing the clamping device to be integrated into complex control systems.

[0008] In some embodiments, both the rigid pressure block and the opposing pad have arc-shaped surfaces facing the hose, and the radius of curvature of the arc-shaped surfaces is adapted to the outer diameter of the hose.

[0009] Both the rigid pressure block and the opposing pad have curved surfaces facing the hose. During clamping, the hose is flattened and then naturally unfolds along the curved surface, forming a gradually increasing contact zone. This avoids localized stress concentration and prevents the hose from being cut or excessively crushed. At the same time, it ensures that the hose is subjected to uniform force, closes smoothly, extends the hose's service life, and improves the reliability of the flow interruption seal.

[0010] In some embodiments, a mechanical limiting structure is also included, disposed within the valve body and located on the movement path of the rigid pressure block, and located on the side of the opposing pad and above the opposing pad, for limiting the maximum movement distance of the rigid pressure block toward the hose.

[0011] The mechanical limiting structure is independent of the opposing pad, located to its side and higher than the highest point of the pad. It stops when the rigid pressure block is pressed down to contact the limiting structure, thus precisely controlling the minimum gap between the pressure block and the pad. This structure prevents excessive pressure from damaging the hose or causing spring overload, extending hose life.

[0012] In some embodiments, it further includes: a linkage bracket, which connects the piston rod of the cylinder to multiple rigid pressure blocks for synchronously driving the opening and closing of multiple hoses.

[0013] A single cylinder, through a linkage bracket, simultaneously drives multiple rigid pressure blocks to perform synchronized lifting and lowering movements, achieving simultaneous clamping or release of multiple parallel-arranged hoses. This structure significantly reduces the number of actuators and control loops, lowering the cost and size of multi-channel systems. It is particularly suitable for applications requiring batch synchronous control, such as multi-channel infusion, multi-channel filling, or parallel reactors, while ensuring the consistency of the on / off actions of each channel.

[0014] Another aspect of this application provides a hose fluid control method based on a pneumatic pinch-off device, applied to the aforementioned hose pinch-off device, the method comprising: Normal flow interruption procedure: Set the pneumatic control switch to the first state or disconnect the air source, depressurize the cylinder, and drive the rigid pressure block to press against the opposite pad block, flattening the hose to block the fluid inside. Flowing procedure: Set the pneumatic control switch to the second state, the cylinder intakes air and overcomes the spring force of the return spring, driving the rigid pressure block away from the opposing pad block, so that the hose can resume flow; Flow interruption recovery steps: interrupt the air intake of the cylinder or restore the pneumatic control switch to the first state, and the reset spring drives the rigid pressure block to press against the opposite pad block again, restoring the flow interruption state.

[0015] Through a three-step control logic of normal flow interruption, flow on, and flow interruption recovery, the device achieves automatic clamping and sealing even in the absence of a gas source or when the switch is reset. It maintains flow interruption without external power, meeting both the safety requirements for gas loss and simplifying the operation process. Users can remotely or locally control the flow of fluid in the hose simply by switching the state of the pneumatic control switch. The entire control process is responsive and reliable, and does not rely on a complex electrical control system, significantly reducing operational difficulty and maintenance costs.

[0016] In some embodiments, a speed adjustment step is also included: By using a one-way throttle valve located at the cylinder exhaust port, during the flow-through step, the cylinder exhaust is quickly discharged through the one-way valve inside the one-way throttle valve, causing the rigid pressure block to quickly move away from the hose. During the flow interruption recovery step, the cylinder exhaust is slowly discharged through the throttle orifice in the one-way throttle valve, causing the rigid pressure block to slowly press against the hose; and the speed at which the rigid pressure block moves away from the hose is greater than the speed at which it presses against the hose, so as to suppress fluid impact.

[0017] The fast-opening, slow-closing operating mode effectively suppresses water hammer in the pipeline, preventing damage to the pipeline and downstream equipment from sudden fluid impacts. The rapid response when opening the valve ensures timely fluid flow, while the slow action when closing the valve gradually flattens the hose, causing the fluid velocity to decrease smoothly and significantly mitigating pipeline pressure fluctuations. Furthermore, the closing speed can be steplessly adjusted by changing the orifice diameter, allowing users to flexibly adapt to the actual fluid characteristics without replacing any hardware.

[0018] In some embodiments, the pneumatic control switch is an electro-optical pilot valve, and the flow-through step and / or flow-out recovery step are triggered by a remote signal, which is selected from electrical signals, wireless signals, or PLC control signals.

[0019] Seamless integration of pneumatic clamping devices with automated control systems eliminates the need for manual on-site operation for hose control. On production lines with multiple devices operating in parallel, operators can simultaneously control the actions of multiple clamping devices from a central control room, achieving centralized scheduling and automated interlocking control. The application of wireless signals further reduces wiring costs and space requirements, making it particularly suitable for applications requiring frequent changes in workstations or mobile equipment.

[0020] In some embodiments, in the event of an unexpected interruption of the air supply or failure of the pneumatic control switch, a normal flow interruption procedure is automatically performed to keep the hose in a flow interrupted state.

[0021] Even in the event of unexpected situations such as a ruptured gas supply line, air compressor failure, or a damaged control switch, the device can automatically switch to a safe flow interruption state to prevent uncontrolled fluid leakage. This function is particularly important in applications with extremely high safety requirements, such as medical infusions, chemical drug delivery, or the control of flammable and explosive fluids. The entire fail-safe process is completed independently by the mechanical force of the return spring, without relying on any external detection or control circuits, exhibiting extremely high reliability and anti-interference capabilities. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the pneumatically controlled normally closed hose clamping device of the present invention. Figure 2 This is a cross-sectional view of the pneumatically controlled normally closed hose clamping device of the present invention. Figure 3 This is a schematic diagram of the structure of the cylinder connected to the rigid pressure block in the pneumatically controlled normally closed hose clamping device of the present invention. Figure 4This is a flowchart of the hose fluid control method based on a pneumatic pinch-off device according to the present invention.

[0023] Figure label: 1. Valve body; 2. Opposing pad; 3. Rigid pressure block; 4. Cylinder; 401. Piston rod; 4011. Piston; 5. Return spring; 6. Pneumatic control switch; 7. One-way throttle valve; 8. Hoses. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0025] This invention provides a pneumatically controlled normally closed hose clamping device. Its core lies in utilizing the normally closed force of the return spring 5 to achieve air loss safety, while simultaneously using a cylinder 4 in conjunction with a one-way throttle valve 7 to achieve fast opening and slow closing. The overall structure is compact and the control is flexible. The following describes each component and its preferred implementation.

[0026] First, the device includes a valve body 1. Inside the valve body 1 is a channel through which a flexible hose 8 passes. Holes are opened on both sides of the valve body 1 corresponding to the channel, allowing the hose 8 to enter and exit. When inserting the hose 8, one end of the hose 8 is first inserted through the inlet on one side of the valve body 1, allowing it to pass horizontally through the channel inside the valve body 1. The two holes are coaxial, with their axes parallel to the direction of the hose 8's passage. When the hose 8 passes through the valve body 1, the inner diameter of the hole matches the outer diameter of the hose 8. This fit restricts the hose 8's movement perpendicular to the axis while ensuring that the hose 8 can be freely pulled axially, facilitating installation and replacement. It should be noted that the holes in this embodiment are only suitable for positioning a single specification of hose 8. If a hose with a different outer diameter is required, a valve body 1 with the corresponding hole diameter should be used. During insertion, it is necessary to ensure that the hose 8 remains naturally straight, without twisting or kinking, within the channel. Because the distance between the inlet and outlet on both sides of the valve body 1 is small (usually only slightly larger than the width of the rigid pressure block 3 and the opposing pad 2), the travel distance of the hose 8 in the channel is very short, and it can be installed by hand without any tools, making the operation very convenient. An opposing pad 2 is fixedly installed inside the valve body 1, and a rigid pressure block 3 that can move up and down is positioned above the opposing pad 2. These two components are arranged opposite each other on both sides of the channel. A cylinder 4 is installed on the outside of the valve body 1, and the piston rod 401 of the cylinder 4 extends into the valve body 1 and is directly connected to the rigid pressure block 3. It is worth noting that a return spring 5 is fitted on the piston rod 401, with its upper end abutting against the inner wall of the valve body 1 and its lower end abutting against the upper surface of the rigid pressure block 3. A pneumatic control switch 6 is connected between the external air source and the air inlet of the cylinder 4 to control the entry and exit of compressed air. In addition, at least one-way throttle valve 7 is installed at the exhaust port of the cylinder 4. The working process of this device is as follows: When the air source is disconnected or the pneumatic control switch 6 is in the first state (i.e., the air source is cut off), the cylinder 4 is depressurized, and the return spring 5 pushes the rigid pressure block 3 against the opposite pad block 2 by its own elastic force, thereby flattening the hose 8 and achieving flow interruption.

[0027] When the pneumatic control switch 6 is switched to the second state (i.e., the air source is on), compressed air enters the cylinder 4, pushing the piston 4011 on the piston rod 401. This causes the piston rod 401 to move upward against the elastic force of the return spring 5, moving the rigid pressure block 3 away from the opposing pad block 2. The hose 8 returns to its original state, allowing air to flow. The one-way throttle valve 7 is used to adjust the speed of movement of the rigid pressure block 3, thus adapting to different working conditions.

[0028] The working principle of the one-way throttle valve 7 is as follows, achieving the beneficial effect of fast opening and slow closing. In the actual air circuit, the one-way throttle valve 7 integrates a one-way valve and a throttle orifice. When cylinder 4 needs to intake air (i.e., open the flow), the original gas in cylinder 4 is discharged from the exhaust port. This exhaust direction causes the one-way valve in the one-way throttle valve 7 to open, allowing the gas to pass through quickly with almost no resistance. Therefore, the rigid pressure block 3 can quickly rise, achieving fast opening. When the pneumatic control switch 6 is reset and the air source is cut off, the compressed gas in cylinder 4 needs to be discharged from the exhaust port. At this time, the exhaust direction causes the one-way valve to close, and the gas can only be slowly squeezed out from the throttle orifice. Therefore, the rigid pressure block 3 is slowly pressed down under the push of the return spring 5, achieving slow closing. By changing the throttle orifice with different diameters, the slow closing time can be easily adjusted, thereby effectively suppressing water hammer impact in the pipeline. The entire device uses only one single-acting cylinder 4, one return spring 5 and one pneumatic switch, eliminating the need for complex double cylinder 4 or linkage mechanisms. It has fewer parts, lower manufacturing costs, and supports subsequent remote control modifications.

[0029] The pneumatic control switch 6 can be either a manual pneumatic push-button valve or an electrically controlled solenoid pilot valve. When using a manual pneumatic push-button valve, it is directly mounted on the outer wall of the valve body 1, with its inlet connected to an air source, its outlet connected to the inlet of cylinder 4, and its exhaust port open to the atmosphere. Pressing the button connects the air source, and releasing the button depressurizes cylinder 4. This manual method is suitable for on-site operation, simple and reliable. When using an electrically controlled solenoid pilot valve, the inlet, outlet, and exhaust ports of the solenoid valve are connected in the same way, and the solenoid valve's electrical control terminal receives remote control signals (e.g., switch signals from a PLC or remote button). Power is applied to connect the air source, and power is de-energized to depressurize cylinder 4. In this way, the device can be integrated into automated production lines or centralized control systems to achieve remote start / stop. Preferably, the solenoid valve can be a two-position three-way type, which meets the normally closed safety requirements and allows for easy interface with various controllers.

[0030] Preferably, both the rigid pressure block 3 and the opposing pad 2 on the side facing the hose 8 are machined into arc-shaped surfaces, and the radius of curvature of these arc-shaped surfaces matches the outer diameter of the hose 8. It should be noted that during clamping, the entire arc-shaped surface does not contact the hose 8 simultaneously. Instead, as the hose 8 is gradually flattened, the hose wall naturally unfolds along the arc-shaped surface, forming a gradually increasing contact band. Compared to flat or sharp-edge compression, this arc-shaped design avoids localized stress concentration, preventing the hose 8 from being cut or excessively crushed. Simultaneously, the hose 8 experiences more uniform stress, and the closing action is smoother, helping to extend the service life of the hose 8 and improve sealing reliability during flow interruption. In particular, this arc-shaped surface structure is especially advantageous for easily damaged elastic hoses 8 such as silicone and latex.

[0031] Preferably, the device further includes a mechanical limiting structure. This limiting structure is located inside the valve body 1, on the movement path of the rigid pressure block 3, and on the side of the opposing pad 2, with its top end higher than the highest point of the opposing pad 2. When the rigid pressure block 3 moves downward and is about to completely flatten the hose 8, it will first contact this limiting structure, thus preventing further downward pressure. In this way, the minimum gap between the rigid pressure block 3 and the opposing pad 2 is precisely defined, ensuring that the hose 8 can be completely blocked while preventing excessive downward pressure from damaging the hose 8 or overloading the return spring 5, thereby extending the lifespan of the hose 8.

[0032] In one specific embodiment, the mechanical limiting structure can be a limiting screw. A threaded hole is formed on the side wall of the valve body 1, located on the side of the opposing pad 2 and above its highest point. The limiting screw is screwed into the threaded hole from the outside of the valve body 1, with its screw end extending into the valve body 1 and moving towards the rigid pressure block 3. During adjustment, the length of the limiting screw extending into the valve body 1 can be changed by rotating it, thereby setting a stop protrusion height. When the rigid pressure block 3 is pushed downward by the return spring 5, its bottom or side will first contact the end of the limiting screw, thus preventing further downward pressure. In this way, the minimum gap between the rigid pressure block 3 and the opposing pad 2 is precisely defined. With this screw structure, the operator can achieve stepless adjustment simply by rotating the screw with a screwdriver. The limiting screw is preferably made of copper or wear-resistant stainless steel to reduce friction and possible sparks when in contact with the rigid pressure block 3. This structure is simple, low-cost, and intuitive to adjust.

[0033] Preferably, the device further includes a linkage bracket. One end of the linkage bracket is fixedly connected to the piston rod 401 of the cylinder 4, and the other end is simultaneously connected to multiple rigid pressure blocks 3. Each rigid pressure block 3 is paired with a corresponding opposing pad block 2, thereby forming multiple independent clamping stations.

[0034] When cylinder 4 actuates, piston rod 401 drives all rigid pressure blocks 3 to rise and fall synchronously via linkage bracket, achieving simultaneous opening and closing of multiple hoses 8. This structure significantly reduces the number of actuators (cylinder 4) and control circuits, lowering the overall cost and footprint of multi-channel systems. This solution is particularly suitable for applications requiring batch synchronous control, such as multi-channel infusion equipment, multi-channel filling equipment, or parallel reactors, and can ensure the consistency of action of each channel.

[0035] The above-described preferred embodiments can be implemented individually or combined according to actual needs. For example, based on the existing arc-shaped surface and mechanical limiting structure, a solenoid valve and a linkage bracket can be added to obtain a normally closed clamping device that can be remotely controlled, multi-channel synchronized, and has a long service life for the hose 8. All components of this device can be manufactured using conventional machining or standard pneumatic components. In terms of materials, the valve body 1 is preferably made of aluminum alloy or engineering plastic, the return spring 5 is made of stainless steel or piano wire, the cylinder 4 is a commercially available miniature single-acting cylinder, and the one-way throttle valve 7 is a standard speed control valve. Those skilled in the art, after reading the above description, can manufacture and use this device without any creative effort.

[0036] This application provides a hose fluid control method based on a pneumatic clamping device, which is applied to the aforementioned hose clamping device.

[0037] The operator first performs the normal flow interruption procedure: setting the pneumatic control switch 6 to the first state, or directly disconnecting the air supply. At this time, the cylinder 4 is connected to the atmosphere and depressurized. The previously compressed return spring 5, no longer resisting the cylinder pressure, uses its stored elastic potential energy to drive the rigid pressure block 3 downwards, pressing against the opposing pad 2, gradually flattening the hose 8 passing between them until the internal fluid is completely blocked. This achieves automatic shut-off in the absence of an air supply.

[0038] Next, the flow-through step is performed: the pneumatic control switch 6 is switched to the second state, and compressed air enters the air inlet of cylinder 4 from an external air source through the switch. The pressure inside the cylinder increases, pushing the piston rod 401 upward. This upward force is sufficient to overcome the downward elastic force of the return spring 5, thereby moving the rigid pressure block 3 away from the opposing pad block 2. The hose 8 returns to its circular cross-section due to its own elasticity and the fluid pressure inside the hose, allowing the fluid to flow smoothly.

[0039] Finally, the flow interruption and recovery steps are as follows: When the air intake of cylinder 4 is interrupted, or when the pneumatic control switch 6 is switched back to the first state, the compressed air in the cylinder is discharged from the exhaust port, the cylinder is depressurized again, and the reset spring 5 drives the rigid pressure block 3 to press against the opposing pad block 2 again, the hose 8 is flattened again, and the fluid flow is restored to the interrupted state.

[0040] In this way, the entire control process only requires operating the pneumatic control switch 6 to switch the flow of fluid through the hose, and the device will automatically return to a safe shut-off state in the event of any power interruption.

[0041] This application adds a speed regulation step to the basic control method. Specifically, a one-way throttle valve 7 is installed at the exhaust port of cylinder 4. This valve integrates a one-way valve and a throttle orifice. During the flow-through step, cylinder 4 needs to discharge the existing gas to allow the piston to move upward. At this time, the direction of the exhaust flow causes the one-way valve in the one-way throttle valve 7 to open, and the gas is discharged quickly with almost no obstruction. Therefore, the rigid pressure block 3 can quickly move upward away from the hose 8, achieving fast opening. During the flow interruption and recovery step, the gas source is cut off, and the compressed gas in cylinder 4 needs to be discharged from the exhaust port. At this time, the direction of the exhaust flow causes the one-way valve to close, and the gas can only be slowly squeezed out from the throttle orifice. Therefore, the rigid pressure block 3 is slowly pressed downward towards the hose 8 under the push of the return spring 5, achieving slow closing. With this configuration, the speed at which the rigid pressure block 3 moves away from the hose 8 is significantly greater than its speed of pressing towards the hose, i.e., fast opening and slow closing. The advantages of this operating mode are: a rapid response when opening the valve ensures timely fluid flow, while a slow action when closing the valve gradually flattens the hose, causing the fluid velocity in the pipeline to decrease smoothly, thus effectively suppressing water hammer. It is worth noting that users can adjust the slow closing speed by changing the orifice diameter; for example, a larger orifice diameter results in faster closure, and a smaller orifice diameter results in slower closure. This allows for flexible adjustment based on actual fluid characteristics without requiring modifications to other parts of the device.

[0042] This application selects an electrically controlled solenoid pilot valve as the pneumatic control switch, specifically a form of pneumatic control switch 6. The solenoid valve's electrical control terminal can receive remote signals from external sources, which can be electrical signals, wireless signals, or PLC control signals. Operators can issue commands from a distance via a central control console, wireless remote control, or the PLC of the automation system, and the solenoid valve automatically switches the air path based on the signal's on / off state. When an opening command is received, the solenoid valve is energized to connect the air source to the cylinder 4, and the cylinder is filled with air, thereby opening the hose 8; When a shutdown command is received, the solenoid valve is de-energized, connecting cylinder 4 to the atmosphere, and the cylinder is depressurized, thereby closing hose 8.

[0043] In this way, the entire device is integrated into the automated control system, eliminating reliance on manual operation on-site. Specifically, on production lines with multiple devices operating in parallel, a central controller can simultaneously control the actions of multiple clamping devices, achieving centralized scheduling and interlocking control. Preferably, the application of wireless signals can further reduce wiring costs, especially suitable for applications requiring frequent changes in workstations or mobile equipment. The solenoid valve itself can be a two-position, three-way type; this type of valve automatically connects cylinder 4 to the atmosphere when power is lost, naturally meeting the requirements for safety in case of gas loss.

[0044] This application utilizes the mechanical force of the return spring 5 to achieve automatic protection. Regardless of whether the air supply is unexpectedly interrupted or the pneumatic control switch 6 itself fails (e.g., the solenoid valve is de-energized, or the manual button is damaged and cannot maintain the second state), the device will automatically execute the normal flow interruption procedure. Specifically, once the air supply pressure is lost or the pneumatic control switch 6 fails to supply air to the cylinder 4, the cylinder immediately depressurizes, and the return spring 5 immediately drives the rigid pressure block 3 to press against the opposing pad block 2, keeping the hose 8 in a flow interrupted state. The entire process requires no human intervention, nor any additional detection circuitry or control signals; it is completed independently entirely by the mechanical force of the return spring 5. This is particularly important in applications with extremely high safety requirements, such as medical infusions, chemical drug delivery, and the control of flammable and explosive fluids—even in the event of an unexpected situation such as a ruptured air supply line, air compressor failure, or damage to the pneumatic control switch 6, the fluid will not leak out of control. It is worth noting that this air loss safety function is an inherent characteristic of the device and is not achieved through additional circuitry; therefore, it has extremely high reliability and anti-interference capabilities, making it suitable for long-term use in harsh industrial environments.

[0045] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A pneumatically controlled, normally closed, hose clamp device, characterized in that include: A valve body (1) is provided with a channel through which a hose (8) passes; a counter-shield (2) and a movable rigid pressure block (3) are fixedly installed inside the valve body (1), the counter-shield (2) and the rigid pressure block (3) being arranged opposite to each other on both sides of the channel; a cylinder (4) is installed on the outside of the valve body (1), the piston rod (401) of the cylinder (4) extending into the valve body (1) and connected to the rigid pressure block (3); a return spring (5) is sleeved on the piston rod (401) and its two ends abut against the inner wall of the valve body (1) and the rigid pressure block (3) respectively; a pneumatic control switch (6) is connected between the air source and the cylinder (4). Between the air inlets, there is a valve for controlling the intake and exhaust of the cylinder (4); and at least one one-way throttle valve (7) is installed at the exhaust port of the cylinder (4); wherein, when the air source is disconnected or the pneumatic control switch (6) is in the first state, the cylinder (4) is depressurized, and the return spring (5) drives the rigid pressure block (3) to move towards the opposite pad (2) to cut off the flow of the hose (8); when the pneumatic control switch (6) is in the second state, the cylinder (4) is inlet and overcomes the elastic force of the return spring (5), so that the rigid pressure block (3) moves away from the opposite pad (2) and the hose (8) is allowed to flow; the one-way throttle valve (7) is used to adjust the moving speed of the rigid pressure block (3).

2. A pneumatically controlled, normally closed hose clamp device and method of control according to claim 1, wherein, The pneumatic control switch (6) is a manual pneumatic push-button valve or an electrically controlled electromagnetic pilot valve. The electrically controlled electromagnetic pilot valve is used to receive remote control signals to control the intake and exhaust of the cylinder (4).

3. The pneumatically controlled, normally closed hose clamp device and method of control of claim 1, wherein, The rigid pressure block (3) and the opposing pad block (2) are both arc-shaped surfaces facing the hose (8), and the radius of curvature of the arc-shaped surfaces is adapted to the outer diameter of the hose (8).

4. The pneumatically controlled, normally closed hose clamp device and method of control of claim 1, wherein, It also includes a mechanical limiting structure, which is located inside the valve body (1) and on the moving path of the rigid pressure block (3), and is located on the side of the opposing pad (2) and above the opposing pad (2), to limit the maximum moving distance of the rigid pressure block (3) toward the hose (8).

5. The pneumatically controlled, normally closed hose clamp device and method of control of claim 1, wherein, Also includes: The linkage bracket connects the piston rod (401) of the cylinder (4) with multiple rigid pressure blocks (3) to synchronously drive the opening and closing of multiple hoses (8).

6. A method of hose fluid control based on a pneumatic pinch device, characterized by, The method, applied to the hose clamping device according to any one of claims 1 to 5, comprises: Normal flow interruption procedure: Set the pneumatic control switch to the first state or disconnect the air source, depressurize the cylinder, and drive the rigid pressure block to press against the opposing pad block to flatten the hose and block the internal fluid. Flow restoration step: Set the pneumatic control switch to the second state, the cylinder is inlet and overcomes the spring force of the reset spring, driving the rigid pressure block away from the opposing pad block, so that the hose can resume flow; Flow interruption recovery step: interrupt the air intake of the cylinder or restore the pneumatic control switch to the first state, and the reset spring drives the rigid pressure block to press against the opposing pad block again to restore the flow interruption state.

7. The method of claim 6, wherein, It also includes speed adjustment steps: By using a one-way throttle valve located at the cylinder exhaust port, during the flow-through step, the cylinder exhaust is rapidly discharged through the one-way valve inside the one-way throttle valve, causing the rigid pressure block to quickly move away from the hose. In the flow interruption recovery step, the cylinder exhaust is slowly discharged through the throttle orifice in the one-way throttle valve, causing the rigid block to slowly press against the hose; and the speed at which the rigid block moves away from the hose is greater than the speed at which it presses against the hose, so as to suppress fluid impact.

8. The method of claim 6, wherein, The pneumatic control switch is an electrically controlled electromagnetic pilot valve. The flow-through step and / or the flow-out recovery step are triggered by a remote signal, which is selected from electrical signals, wireless signals, or PLC control signals.

9. The method of claim 6, wherein, In the event of an unexpected interruption of the air supply or failure of the pneumatic control switch, the normal flow interruption procedure is automatically executed to keep the hose in a flow interrupted state.

Images