A stiffness regulating valve for a multi-chamber air spring

Abstract

This utility model discloses a stiffness regulating valve for a multi-chamber air spring, relating to the field of automotive control equipment technology. It is used to adjust the opening size of the air passage connecting the air spring. The valve includes a housing and a motor built into the housing. A lead screw and a piston are disposed inside the housing. One end of the lead screw is connected to the motor, and the other end is fixedly connected to the piston. The position of the piston corresponds to the air passage. The motor includes a stator and a rotor. The rotor has a drive threaded hole along its axis, and the lead screw engages with the drive threaded hole to form a transmission connection. This utility model, through a unique structural design, directly drives the lead screw for transmission, improving transmission accuracy. Placing the lead screw inside the motor rotor significantly saves axial space in the valve body, achieving high integration, improving space utilization, and reducing processing costs.

Description

Technical Field

[0001] This utility model belongs to the technical field of vehicle control equipment, and in particular relates to a stiffness regulating valve for a multi-chamber air spring. Background Technology

[0002] The current development trend of automotive suspension is towards air suspension and electronically controlled suspension, because air suspension can greatly improve ride comfort and is favored by many OEMs and customers.

[0003] Air springs possess ideal non-linear elastic characteristics. With the addition of a height adjustment device, the vehicle height remains constant regardless of load changes, allowing for a lower spring stiffness and improved ride comfort. Their working principle involves filling a sealed pressure cylinder with inert gas or an oil-gas mixture, creating a pressure several times or even tens of times higher than atmospheric pressure. The piston rod's movement is achieved by utilizing the pressure difference generated when its cross-sectional area is smaller than the piston's. Due to this fundamental difference in principle, air springs offer significant advantages over ordinary springs: relatively slower speed, minimal dynamic force variation (generally within 1:1.2), and easier control. Disadvantages include a smaller relative volume compared to coil springs, higher cost, and a relatively shorter lifespan.

[0004] Air springs are widely used in self-adjusting air suspension systems for commercial vehicles, buses, rail vehicles, machinery, and building foundations. Air springs are also known as support rods, angle adjusters, gas bars, and dampers. Based on their structure and function, air springs can be classified into several types, including free-type air springs, self-locking air springs, traction air springs, freely adjustable air springs, swivel chair air springs, gas bars, and dampers. This product has wide applications in the automotive, aerospace, medical equipment, furniture, and machinery manufacturing industries.

[0005] Currently, air springs are inevitably used in the use of air suspension in automobiles. However, while air springs improve ride comfort, their stiffness cannot be adjusted, thus failing to provide lateral support for the air suspension. This inevitably leads to a decrease in the handling stability of the air suspension, reducing handling stability and safety.

[0006] For example, patent number "CN119333510A" discloses a stiffness regulating valve for a multi-chamber air spring in a passenger vehicle, which is a stiffness regulating valve specifically for air springs previously applied for by the applicant. It includes: a connecting air passage, one end of which is connected to the air spring, with an air port on the side wall of the connecting air passage, and a first sealing part at the connection between the connecting air passage and the air spring; a stiffness valve housing, fixed to the other end of the connecting air passage, with a second sealing part between the connecting air passage and the stiffness valve housing, and the air port located outside the stiffness valve housing; a piston for controlling the opening size of the air port, the piston being slidably disposed within the connecting air passage, and a third sealing part between the connecting air passage and the piston; a sliding drive unit for driving the piston to slide within the connecting air passage; a reduction unit, the output end of which is drively connected to the sliding drive unit; and a drive unit, the input end of which is drively connected to the input end of the reduction unit. In use, the opening size of the air port is controlled by driving the piston to move within the connecting air passage, thereby adjusting the stiffness of the air spring. During actual use, the applicant still found areas for further optimization, such as: further optimizing the product structure, further increasing the accuracy of the stiffness regulating valve, and further reducing the external dimensions of the stiffness regulating valve. Utility Model Content

[0007] The purpose of this invention is to solve the problems of poor precision, excessive size, and difficulty in processing and installation of the adjustment valve of the air spring in existing automotive air suspensions.

[0008] To achieve the purpose of this utility model, the technical solution of this utility model is as follows: A stiffness regulating valve for a multi-chamber air spring, used to adjust the opening size of the air passage of the air spring, includes a housing and a motor built into the housing. The housing contains a lead screw and a piston. One end of the lead screw is connected to the motor, and the other end of the lead screw is fixedly connected to the piston. The position of the piston corresponds to the air passage. The motor includes a stator and a rotor. The rotor has a drive threaded hole along its axis. The lead screw meshes with the drive threaded hole to form a drive connection structure.

[0009] Preferably, the piston includes a piston shell and a connecting member. The piston shell has a third through hole at its center. The connecting member has a protrusion that passes through the third through hole. The protrusion and the third through hole are in clearance fit. A piston sealing gasket is provided between the connecting member and the piston shell. Preferably, the end of the lead screw away from the motor has a ball head structure, the connector has a connecting groove adapted to the shape of the ball head structure, the lead screw is also fitted with a retaining spring, and the groove wall of the connecting groove has a fixing groove for fixing the retaining spring.

[0010] Preferably, the lead screw is provided with a limiting disc, and the housing is also provided with an anti-rotation protrusion. The anti-rotation protrusion is fixedly connected to the inner wall of the housing, and the limiting disc is slidably connected to the anti-rotation protrusion. The lead screw and the anti-rotation protrusion are in a spline tooth clearance fit, and the lead screw and the anti-rotation protrusion are in a clearance fit with each other, which guides the linear reciprocating motion of the lead screw and prevents the lead screw from rotating.

[0011] Furthermore, the limiting plate is provided with a groove that matches the anti-rotation protrusion, and the limiting plate and the anti-rotation protrusion are slidably connected through the groove.

[0012] Furthermore, the rotation of the motor rotor drives the lead screw to reciprocate linearly via a threaded transmission.

[0013] Furthermore, the piston gasket provides a cushioning effect during the operation of the lead screw.

[0014] Preferably, the connector has linear protrusions to provide a line contact seal.

[0015] Preferably, the housing includes a first housing, a second housing, a first cover plate, and a second cover plate. The first housing has a first cavity, and the motor is placed in the first cavity. The second housing is fixed to the inside of the first housing and is located at the front end of the motor. The second housing has a first through hole at its center for the lead screw to pass through. The first cover plate is fixed to the inside of the first housing and is located at the front end of the second housing. It covers the second housing to form a second cavity, and the piston is placed in the second cavity. The first cover plate has a second through hole at its center for the piston to pass through. The second cover plate is fixed to the inside of the first housing and is located at the rear end of the motor. The first housing covers the outer surfaces of the motor, the second housing, the first cover plate, and the second cover plate.

[0016] Preferably, a first sealing ring is provided on the outer side of the connecting air passage, a second sealing ring is provided on the outer side of the first cover plate, a third sealing ring is provided at the connection between the first housing and the second cover plate, and a fourth sealing ring is provided on the outer side of the second cover plate.

[0017] Preferably, the lead screw is a trapezoidal lead screw.

[0018] Preferably, a fifth sealing ring is provided on the side of the piston that mates with the communicating air passage.

[0019] Preferably, the housing is provided with a PCB board, and control lines are led out from the PCB board. The end of the housing away from the air passage is provided with an integrated plug interface, and the control lines are arranged in the plug interface. The motor is provided with a motor sensor, and the motor and the motor sensor are electrically connected to the PCB board.

[0020] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. The multi-chamber air spring stiffness regulating valve proposed in this utility model directly connects the lead screw to the motor for transmission, eliminating intermediate parts such as reducers and couplings, reducing transmission errors, and directly realizing precise adjustment of the lead screw and piston through high-precision control of the motor, thereby improving transmission accuracy.

[0021] 2. This utility model proposes a stiffness regulating valve for a multi-chamber air spring, which can achieve high-precision control of the air spring port opening. The piston is driven by a sliding drive unit to reciprocate within the connecting air passage to control the size of the air port opening, thereby controlling the exhaust speed and adjusting the stiffness of the air spring.

[0022] 3. The present invention proposes a stiffness regulating valve for a multi-chamber air spring, wherein the working part of the transmission screw is located inside the motor rotor, which greatly saves the overall axial dimension space. Moreover, the transmission screw has a trapezoidal thread, which can realize a self-locking function, so that the piston can be naturally maintained in a fixed position without consuming energy when the air port opening is kept consistent.

[0023] 4. The present invention proposes a stiffness regulating valve for a multi-chamber air spring, which replaces the traditional "electromagnetic coil + moving and stationary iron core" structure with a "motor + trapezoidal screw structure" to achieve the switching function. When the valve is closed, the moving iron core rapidly impacts the stationary iron core, which generates a lot of impact noise. The present invention can adjust the impact speed when the valve is closed, effectively reducing noise. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of the opening state of a stiffness regulating valve for a multi-chamber air spring according to this utility model. Figure 2 This is a cross-sectional view of the closed state of a stiffness regulating valve for a multi-chamber air spring according to this utility model; Figure 3 This is one of the detailed structural diagrams of the internal structure of a stiffness regulating valve; Figure 4 This is the second detailed structural diagram of the internal structure of the stiffness regulating valve; Figure 5 This is the third detailed structural diagram of the internal structure of the stiffness regulating valve; Component names and serial numbers: 1. Housing; 11. First housing; 12. Second housing; 13. First cover plate; 14. Second cover plate; 2. Motor; 21. Stator; 22. Rotor; 221. Transmission threaded hole; 23. Motor sensor; 3. Lead screw; 31. Ball head structure; 32. Limiting plate; 4. Piston; 41. Piston housing; 42. Piston sealing gasket; 43. Connecting piece; 5. Snap ring; 6. Anti-rotation protrusion; 7. Connecting air passage; 71. First sealing ring; 72. Second sealing ring; 73. Third sealing ring; 74. Fourth sealing ring; 75. Fifth sealing ring; 8. Connector; 9. Control circuit. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. The following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0026] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning as understood by a person skilled in the art to which this disclosure pertains. The words “comprising” or “including” or similar terms used in this disclosure mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0027] like Figures 1-5As shown, this utility model proposes a stiffness regulating valve for a multi-chamber air spring, used to adjust the opening size of the air passage 7 connecting the air spring. It includes a housing 1 and a motor 2 built into the housing 1. The housing 1 contains a lead screw 3 and a piston 4. One end of the lead screw 3 is connected to the motor 2, and the other end is fixedly connected to the piston 4. The position of the piston 4 corresponds to the air passage 7. The motor 2 includes a stator 21 and a rotor 22. The rotor 22 has a transmission threaded hole 221 along its axis. The lead screw 3 engages with the transmission threaded hole 221 to form a transmission connection structure. In use, the air passage 7 is connected to two different chambers of the air spring. The motor 2 directly drives the lead screw 3 to move linearly, which in turn pushes the piston 4 to move linearly, thereby changing the opening size of the air passage 7 to control the intake and exhaust speeds, ultimately adjusting the stiffness of the air spring. This invention, by establishing a transmission threaded hole 221 within the rotor 22, allows the rotor 22 to directly drive the lead screw 3 to perform linear motion, directly saving the use of intermediate transmission components such as reducers or couplings and eliminating transmission errors caused by such transmission parts. Furthermore, since the lead screw 3 is located inside the rotor 22 and coincides with the rotor 22 in the axial direction, it fully utilizes the internal space of the rotor 22, greatly shortening the axial dimension of the valve body. Specifically, compared to the stiffness regulating valve for multi-chamber air springs in passenger vehicles disclosed in patent number "CN119333510A", the technical solution of this invention reduces the volume by 17%-20% and the axial length by 17-20mm, achieving high integration and significantly reducing processing and production costs, making it worthy of promotion.

[0028] Specifically, the piston 4 includes a piston shell 41 and a connecting member 43. The piston shell 41 has a third through hole at its center, and the connecting member 43 has a protrusion passing through the third through hole. The protrusion and the third through hole are in clearance fit. A piston sealing gasket 42 is provided between the connecting member 43 and the piston shell 41. This utility model adopts a split design for the piston 4. Through the clearance fit between the connecting member 43 and the piston shell 41 and the assistance of the piston sealing gasket 42, a small portion of the gas in the connecting air passage 7 can enter the valve body through the gap, so that there is a certain safety gas margin in the valve body during operation. In addition, the piston sealing gasket 42 can also play a certain buffering role for the lead screw 3, improving the safety of the valve body during operation.

[0029] Specifically, the end of the lead screw 3 furthest from the motor 2 has a ball-head structure 31. The connecting member 43 has a connecting groove that matches the shape of the ball-head structure 31. A retaining ring 5 is also fitted onto the lead screw 3, and the groove wall of the connecting groove has a fixing groove for fixing the retaining ring 5. The ball-head structure 31 design of the lead screw 3 allows the connection angle between the lead screw 3 and the piston 4 to be adaptively adjusted within a certain range, improving the compatibility of the valve body.

[0030] Specifically, the housing 1 includes a first housing 11, a second housing 12, a first cover plate 13, and a second cover plate 14. The first housing 11 has a first cavity, and the motor 2 is placed in the first cavity. The second housing 12 is fixed to the inside of the first housing 11 and is located at the front end of the motor 2. The second housing 12 has a first through hole in its center for the lead screw 3 to pass through. The first cover plate 13 is fixed to the inside of the first housing 11 and is located at the front end of the second housing 12. It covers the second housing 12 to form a second cavity, and the piston 4 is placed in the second cavity. The first cover plate 13 has a second through hole in its center for the piston 4 to pass through. The second cover plate 14 is fixed to the inside of the first housing 11 and is located at the rear end of the motor 2. The first housing 11 covers the outer surfaces of the motor 2, the second housing 12, the first cover plate 13, and the second cover plate 14. A first sealing ring 71 is provided on the outer side of the connecting air passage 7, a second sealing ring 72 is provided on the outer side of the first cover plate 13, a third sealing ring 73 is provided at the connection between the first housing 11 and the second cover plate 14, and a fourth sealing ring 74 is provided on the outer side of the second cover plate 14. Since the motor 2, the second housing 12, the first cover plate 13, and the second cover plate 14 are all wrapped and sealed by the first housing 11, the piston 4 is located in a sealed environment, which reduces the operating force required to open and close the piston 4 when the lead screw 3 pushes the piston 4.

[0031] Specifically, the lead screw 3 is provided with a limiting plate 32, which is located in the second cavity. The diameter of the limiting plate 32 is larger than the diameter of the first through hole and the second through hole. An anti-rotation protrusion 6 is also provided in the second cavity. The anti-rotation protrusion 6 is fixedly connected to the inner wall of the second housing 12 and the first cover plate 13. The limiting plate 32 is provided with a groove adapted to the anti-rotation protrusion 6, and the limiting plate 32 is slidably connected to the anti-rotation protrusion 6.

[0032] The cooperation between the limiting plate 32 and the anti-rotation protrusion 6 can prevent the lead screw 3 from rotating and affecting the transmission accuracy, and can also guide and limit the lead screw 3 to maintain the stability of the lead screw 3's movement.

[0033] Specifically, the lead screw 3 is a trapezoidal lead screw; it can realize a self-locking function, so that the opening and closing size of the valve port can stay at any position without external force to maintain it, and the size is controllable, so that the static current is close to zero in any working state.

[0034] Specifically, a fifth sealing ring 75 is provided on the side of the piston 4 that mates with the connecting air passage 7. This prevents gas from escaping when the valve port is fully closed.

[0035] Specifically, a PCB board is provided inside the housing 1, and control lines 9 are led out from the PCB board. An integrated connector 8 is provided at the end of the housing 1 away from the connecting air passage 7, and the control lines 9 are arranged in the connector 8. A motor sensor 23 is provided on the motor 2, and both the motor 2 and the motor sensor 23 are electrically connected to the PCB board. This utility model integrates the PCB board, motor 2, and valve body into a single package, greatly improving the integration of the valve body, reducing processing costs, and allowing the PCB board to monitor the position of the motor 2 rotor 22 via the motor sensor 23 for automatic adjustment.

[0036] The parameter comparison between the product of this application embodiment and the patent number "CN119333510A" is shown in Table 1.

[0037] Table 1 Parameter Comparison Table

[0038] The axial length detection method and spatial volume measurement method in Table 1 are conventional size measurement methods; the cost calculation method is to calculate the cost price by summing the production cost of each part by the supplier; the accuracy measurement method is to measure the piston displacement by a high-precision motor position sensor.

[0039] This invention proposes a stiffness regulating valve for a multi-chamber air spring. A transmission threaded hole 221 is provided inside the rotor 22 along the axial direction, directly engaging with the lead screw 3. The electronic rotor 22 directly drives the lead screw 3 to move linearly, thereby pushing the piston 4 to expand or shrink the distance between it and the connecting air passage 7. This controls the opening size of the air passage 7, thus affecting the stiffness of the air spring. Compared to the applicant's previous first-version stiffness regulating valve, the control accuracy is improved by 8 times, the volume is reduced by 17%, the axial length is reduced by 20mm, and the cost is reduced by 40%.

[0040] The above description is a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in this utility model, based on the technical solution and concept of this utility model, should be covered within the protection scope of the claims of this utility model.

Claims

1. A stiffness regulating valve for a multi-chamber air spring, used to adjust the opening size at the air passage (7) of the air spring, comprising a housing (1) and a motor (2) built into the housing (1), characterized in that: The housing (1) is provided with a lead screw (3) and a piston (4). One end of the lead screw (3) is connected to the motor (2), and the other end of the lead screw (3) is fixedly connected to the piston (4). The position of the piston (4) corresponds to the connecting air passage (7). The motor (2) includes a stator (21) and a rotor (22). The rotor (22) is provided with a transmission threaded hole (221) along the axis inside. The lead screw (3) meshes with the transmission threaded hole (221) to form a transmission connection structure.

2. The stiffness regulating valve for a multi-chamber air spring according to claim 1, characterized in that: The piston (4) includes a piston shell (41) and a connector (43). The piston shell (41) has a third through hole at its center. The connector (43) has a protrusion that passes through the third through hole. The protrusion and the third through hole are in clearance fit. A piston sealing gasket (42) is provided between the connector (43) and the piston shell (41).

3. The stiffness regulating valve for a multi-chamber air spring according to claim 2, characterized in that: The end of the lead screw (3) away from the motor (2) is a ball head structure (31). The connector (43) is provided with a connecting groove that matches the shape of the ball head structure (31). The lead screw (3) is also fitted with a retaining ring (5). The groove wall of the connecting groove is provided with a fixing groove for fixing the retaining ring (5).

4. The stiffness regulating valve for a multi-chamber air spring according to claim 1, characterized in that: The lead screw (3) is provided with a limiting plate (32), and the housing (1) is also provided with an anti-rotation protrusion (6). The anti-rotation protrusion (6) is fixedly connected to the inner wall of the housing (1), and the limiting plate (32) is slidably connected to the anti-rotation protrusion (6).

5. The stiffness regulating valve for a multi-chamber air spring according to claim 4, characterized in that: The limiting plate (32) is provided with a groove that matches the anti-rotation protrusion (6), and the limiting plate and the anti-rotation protrusion are slidably connected through the groove.

6. A stiffness regulating valve for a multi-chamber air spring according to any one of claims 1-5, characterized in that: The housing (1) includes a first housing (11), a second housing (12), a first cover plate (13), and a second cover plate (14). The first housing (11) has a first cavity, and the motor (2) is placed in the first cavity. The second housing (12) is fixed to the inside of the first housing (11) and placed at the front end of the motor (2). The second housing (12) has a first through hole in the center for the lead screw (3) to pass through. The first cover plate (13) is fixed to the inside of the first housing (11) and placed at the front end of the second housing (12). It covers the second housing (12) to form a second cavity. The piston (4) is placed in the second cavity. The first cover plate (13) has a second through hole in the center for the piston (4) to pass through. The second cover plate (14) is fixed to the inside of the first housing (11) and placed at the rear end of the motor (2). The first housing (11) wraps around the outer surfaces of the motor (2), the second housing (12), the first cover plate (13), and the second cover plate (14).

7. The stiffness regulating valve for a multi-chamber air spring according to claim 6, characterized in that: The outer side of the connecting air passage (7) is provided with a first sealing ring (71), the outer side of the first cover plate (13) is provided with a second sealing ring (72), the connection between the first housing (11) and the second cover plate (14) is provided with a third sealing ring (73), and the outer side of the second cover plate (14) is provided with a fourth sealing ring (74).

8. A stiffness regulating valve for a multi-chamber air spring according to any one of claims 1-5, characterized in that: The lead screw (3) is a trapezoidal lead screw.

9. A stiffness regulating valve for a multi-chamber air spring according to any one of claims 1-5, characterized in that: The piston (4) is provided with a fifth sealing ring (75) on the side that mates with the connecting air passage (7).

10. A stiffness regulating valve for a multi-chamber air spring according to any one of claims 1-5, characterized in that: The housing (1) is provided with a PCB board, and a control line (9) is led out from the PCB board. The end of the housing (1) away from the connecting air passage (7) is provided with an integrated plug interface (8), and the control line (9) is arranged in the plug interface (8). The motor (2) is provided with a motor sensor (23), and the motor (2) and the motor sensor (23) are electrically connected to the PCB board.

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