A dynamically extendable and retractable auxiliary support device

Abstract

The application discloses a kind of auxiliary support devices of dynamic extension, including the actuator capable of vertical extension, the upper end outside of the actuator is equipped with shell, rotating sealing structure is equipped between the shell and the upper end of actuator, the lower end of the actuator is connected with auxiliary wheel by knuckle joint.The purpose of the present application is to provide a kind of auxiliary support devices of dynamic extension, which is installed on the frame of multi-axle special vehicle, for the large change of multi-axle special vehicle carrying range, especially in the special working condition of short-time impact load required to be borne in the process of maneuvering, without parking, in the process of maneuvering, it can also meet the carrying demand.

Description

Technical Field

[0001] This invention relates to the field of special vehicles, and in particular to an auxiliary support device for use on special vehicles. Background Technology

[0002] The loads borne by multi-axle heavy-duty special vehicles are generally distributed through the chassis to the suspension systems of each axle, and then further distributed to the road surface via the tires. This method is sufficient when the load range borne by the chassis does not vary significantly. However, when the load range borne by the chassis varies greatly, especially when subjected to short-term, high-tonnage impact loads during maneuvering, suspension systems and tires designed for conventional load-bearing capacity struggle to withstand the load. Traditionally, two methods have been employed to address this: (1) Before the impact load is applied, stop the vehicle, lower the outriggers, and let them bear the load together with the suspension system. However, this method requires stopping the vehicle at a selected point in advance, lowering the outriggers, etc., and then retracting the outriggers and restarting the vehicle after the load is applied. The parking time is long, and it is necessary to add outriggers and unfold and retract the process. It is also necessary to select a parking location, which affects the vehicle's maneuverability and the speed of task completion.

[0003] (2) The vehicle load is designed according to the impact load to meet the sudden increase in load requirements during operation. However, the impact load is only a special working condition that is short-term and infrequent. This method will inevitably increase the size of the vehicle, resulting in excessive redundancy and waste. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamically retractable auxiliary support device that is installed on the frame of a multi-axle special vehicle. This device is designed for multi-axle special vehicles with a large variation in load-bearing capacity, especially in special working conditions where they need to withstand short-term impact loads during operation. It can meet the load-bearing requirements without stopping the vehicle and can be used during operation.

[0005] The present invention provides a dynamically extendable and retractable auxiliary support device, comprising an actuator capable of vertical extension and retraction. A housing is fitted around the upper outer side of the actuator, and a rotary sealing structure is provided between the housing and the upper end of the actuator. An auxiliary wheel is connected to the lower end of the actuator via a steering knuckle.

[0006] The present invention provides a dynamically extendable auxiliary support device, wherein the actuator is a hydraulic cylinder with the piston on top and the piston rod facing downward. A cylindrical shell is fitted around the cylinder barrel of the hydraulic cylinder, and a rotary sealing structure is provided between the shell and the cylinder barrel of the hydraulic cylinder. The lower end of the piston rod of the hydraulic cylinder is connected to an auxiliary wheel through a steering knuckle.

[0007] The present invention provides a dynamically extendable and retractable auxiliary support device, wherein the cylinder cavity of the hydraulic cylinder is divided by a piston into an upper positive cavity and a lower negative cavity, both of which can be connected to an oil source, and the positive cavity is connected to an accumulator.

[0008] The present invention provides a dynamically retractable auxiliary support device, wherein the piston is provided with a one-way valve that connects the positive cavity to the negative cavity and isolates the negative cavity from the positive cavity, and the piston is also provided with a damping hole that connects the positive cavity and the negative cavity.

[0009] The present invention provides a dynamically extendable auxiliary support device, wherein a sleeve is fixedly sleeved on the outer side of the lower end of the piston rod, the sleeve is connected to the steering knuckle, and the steering knuckle is connected to the auxiliary wheel.

[0010] The present invention provides a dynamically retractable auxiliary support device, wherein the outer side of the housing is fixedly provided with a mounting bracket for fixed connection with the vehicle frame.

[0011] The present invention provides a dynamically retractable auxiliary support device, wherein the auxiliary wheel is an aircraft tire, a solid tire, a metal tire, a composite structure tire, or a tire with an internal support frame.

[0012] The present invention provides a dynamically retractable auxiliary support device, wherein the auxiliary wheel is arranged with a single tire.

[0013] The present invention provides a dynamically retractable auxiliary support device, wherein the auxiliary wheel is arranged coaxially with dual tires.

[0014] The present invention provides a dynamically retractable auxiliary support device, wherein the accumulator is a diaphragm accumulator or a piston accumulator, the accumulator includes a liquid chamber and a gas chamber, and the positive chamber is connected to the liquid chamber of the accumulator.

[0015] The difference between this invention's dynamically retractable auxiliary support device and existing technologies lies in its operation. In this invention, the outer housing of the actuator is fixedly mounted on the frame of a multi-axle special vehicle. Normally, when the frame is not subjected to short-term impact loads, the actuator is in an upward-retracted state, and the auxiliary wheel is not in contact with the road surface. When a short-term impact load is required, the actuator extends downward, and the auxiliary wheel moves downward under the actuator's influence until it contacts the road surface. During vehicle movement, the auxiliary wheel rolls along the road surface. This, along with the actuator, provides additional support points to the frame, enabling the frame to withstand short-term impact loads. After the short-term impact load disappears, the actuator retracts upward again, causing the auxiliary wheel to move upward until it leaves the road surface. When the auxiliary wheel and actuator support the chassis, i.e., when the actuator is in the downward-extended state and the auxiliary wheel is in contact with the road surface, the rotary seal structure between the housing and the upper end of the actuator isolates the relative movement between them. Therefore, when the housing is subjected to lateral loads from the chassis, the lateral loads are not transmitted to the actuator, thus preventing the lateral loads transmitted from the chassis from affecting the actuator. Since the lower end of the actuator is connected to the auxiliary wheel via a steering knuckle, and the steering knuckle can move relative to the lower end of the actuator, the steering knuckle can prevent the lateral loads transmitted from the auxiliary wheel from affecting the actuator. Thus, the actuator only bears axial loads and not lateral loads. This invention isolates the load-bearing components for lateral and axial loads, making the support device simpler, occupying less space, facilitating modular chassis layout, and resulting in a more compact design. Therefore, this invention, when installed on the chassis of multi-axle special vehicles, addresses the special conditions of multi-axle special vehicles with large variations in load-bearing range, especially the need to withstand short-term impact loads during maneuvering, without requiring the vehicle to stop and meeting load-bearing requirements during operation. It should be noted that the number and location of auxiliary support devices installed on the vehicle can be determined based on the actual situation.

[0016] The invention will now be further described with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the dynamically retractable auxiliary support device of the present invention. Figure 1 (The actuator is in the retracted state); Figure 2 This is a schematic diagram of the structure of the dynamically retractable auxiliary support device of the present invention. Figure 2 (The actuator is in the extended state).

[0018] Figure reference numerals: 01. Chassis; 02. Hydraulic cylinder; 03. Positive cavity; 04. Damping orifice; 05. Liquid cavity; 06. Gas cavity; 07. Accumulator; 08. Housing; 09. Piston rod; 10. Auxiliary wheel; 11. Steering knuckle; 12. Stop block; 13. Sleeve; 14. Mounting bracket; 15. Reverse cavity; 16. Piston; 17. Check valve; 18. Rotary sealing structure. Detailed Implementation

[0019] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0020] like Figure 1 , 2 As shown, the dynamically extendable auxiliary support device of the present invention includes an actuator capable of vertical extension and retraction. A housing 08 is fitted around the upper outer side of the actuator, and a rotary sealing structure 18 is provided between the housing 08 and the upper end of the actuator. An auxiliary wheel 10 is connected to the lower end of the actuator via a steering knuckle 11. The steering knuckle 11 is hinged to the lower end of the actuator, meaning that the steering knuckle 11 can move relative to the actuator. The steering knuckle 11 and its connection to the auxiliary wheel 10 are existing technologies and will not be described in detail here.

[0021] The actuator is a hydraulic cylinder 02 with piston 16 on top and piston rod 09 facing downward. A cylindrical housing 08 is fitted around the cylinder barrel of the hydraulic cylinder 02. The housing 08 and the cylinder barrel of the hydraulic cylinder 02 are arranged coaxially. A rotary sealing structure 18 is provided between the housing 08 and the cylinder barrel of the hydraulic cylinder 02. The rotary sealing structure 18 can be a rotary sealing ring plus an oil-free bearing. The lower end of the piston rod 09 of the hydraulic cylinder 02 is connected to an auxiliary wheel 10 through a steering knuckle 11.

[0022] In the specific arrangement of the rotary seal structure 18, two sets can be set. Each set of rotary seal structure 18 includes a rotary seal ring and an oilless bearing. The two sets of rotary seal structures 18 are respectively arranged near the upper end and the middle of the cylinder, that is, the two sets of rotary seal structures 18 are arranged vertically and alternately. The cylinder is rotatably mounted in the cavity of the housing 08 through the oilless bearings in the two sets of rotary seal structures 18. The rotary seal rings in both sets of rotary seal structures are installed between the cylinder and the housing. The rotary seal ring and the oilless bearing are both existing technologies, and their specific structures and working principles will not be described in detail.

[0023] A sleeve 13 is fixedly fitted onto the outer side of the lower end of the piston rod 09. The sleeve 13 is connected to the steering knuckle 11 (the specific connection method is hinged), and the steering knuckle 11 is connected to the auxiliary wheel 10. The steering knuckle 11 is hinged to the sleeve 13, and the steering knuckle 11 can move relative to the lower end of the piston rod 09. A stop block 12 is fixedly provided on the lower end of the piston rod 09 to prevent the steering knuckle 11 from falling off the sleeve 13.

[0024] The cylinder chamber of the hydraulic cylinder 02 is divided by the piston 16 into an upper positive chamber 03 and a lower negative chamber 15. Since the piston 16 of the hydraulic cylinder 02 is arranged on top and the piston rod 09 is arranged downwards, the upper rodless chamber of the hydraulic cylinder 02 is the positive chamber 03, and the lower rod chamber is the negative chamber 15. Both the positive chamber 03 and the negative chamber 15 can be connected to an oil source. The positive chamber 03 is connected to the accumulator 07. The piston 16 is provided with a one-way valve 17 that connects the positive chamber 03 to the negative chamber 15 and disconnects the negative chamber 15 from the positive chamber 03. The piston 16 is also provided with a damping orifice 04 that connects the positive chamber 03 and the negative chamber 15.

[0025] When specifically configuring the check valve 17, a medium flow channel connecting the positive cavity 03 and the negative cavity 15 is first opened on the piston 16, and then the check valve 17 is installed in the medium flow channel. When the oil in the positive cavity 03 flows through the medium flow channel, it can flow to the negative cavity 15 through the conduction of the check valve 17. However, when the oil in the negative cavity 15 flows through the medium flow channel, it is blocked by the check valve 17 and cannot flow to the positive cavity 03 through the check valve 17. The damping orifice 04 also connects the positive cavity 03 and the negative cavity 15. The oil in the positive cavity 03 can flow into the negative cavity 15 through the damping orifice 04, and the oil in the negative cavity 15 can also flow into the positive cavity 03 through the damping orifice 04.

[0026] like Figure 1 , 2 As shown, the present invention provides a dynamically retractable auxiliary support device, wherein a mounting bracket 14 for fixed connection with a vehicle frame 01 is fixedly provided on the outer side of the housing 08. The auxiliary support device can be fixedly mounted on the vehicle frame 01 via the mounting bracket 14.

[0027] This invention relates to a dynamically extendable and retractable auxiliary support device, wherein the auxiliary wheel 10 is an aircraft tire, a solid tire, a metal tire, a composite structure tire, or a tire with an internal support frame. The auxiliary wheel 10 is arranged with a single tire. Of course, the auxiliary wheel 10 can also be arranged with two tires mounted on the same axle.

[0028] This invention relates to a dynamically retractable auxiliary support device, wherein the accumulator 07 is a diaphragm-type accumulator 07, comprising a liquid chamber 05 and a gas chamber 06, with the positive cavity 03 communicating with the liquid chamber 05 of the accumulator 07. Alternatively, the accumulator 07 is a piston-type accumulator 07, comprising a liquid chamber 05 and a gas chamber 06, with the positive cavity 03 communicating with the liquid chamber 05 of the accumulator 07. The accumulator 07 is prior art; its specific structure and working principle will not be described in detail here.

[0029] like Figure 1 , 2 As shown, in use, the hydraulic cylinder 02 is fixedly mounted on the frame 01 of a multi-axle special vehicle. Specifically, the housing 08 is fixedly mounted on the frame 01 via the mounting bracket 14, and both the positive chamber 03 and the negative chamber 15 of the hydraulic cylinder 02 are connected to the oil source. Its working process is as follows: (1) When the vehicle is driving under normal operating conditions, it is supported by the conventional suspension system and wheels. The auxiliary support device is retracted, that is, the piston rod 09 of the hydraulic cylinder 02 is retracted upwards, and the auxiliary wheel 10 is lifted off the ground and does not bear the load. Of course, at this time, the positive chamber 03 and the negative chamber 15 of the hydraulic cylinder 02 are filled with high-pressure oil.

[0030] (2) Before the short-term heavy impact load is required, under the action of the power oil source, the positive chamber 03 of the hydraulic cylinder 02 is filled with oil, and the oil in the reverse chamber 15 flows back to the oil source, so that the piston 16 drives the piston rod 09 to extend and lower quickly. The auxiliary wheel 10 is supported on the road surface and moves with the vehicle. At this time, the conventional wheels still bear the functions of driving, steering and braking. By cutting off the connection between the oil source and the hydraulic cylinder 02, the auxiliary support device passively follows the vehicle.

[0031] (3) When the vehicle is in motion, uneven road surfaces can cause the auxiliary wheel 10 to bounce up or down. When there is a bump in the road surface, the auxiliary wheel 10 moves upward, the piston rod 09 of the hydraulic cylinder 02 retracts, and the oil in the positive cavity 03 flows into the negative cavity 15 through the one-way valve 17 and the damping hole 04. The excess oil is pumped into the accumulator 07, resulting in low system damping. When there is a depression in the road surface, the auxiliary wheel 10 moves downward, the piston rod 09 of the hydraulic cylinder 02 extends, and the oil in the negative cavity 15 can only flow into the positive cavity 03 through the damping hole 04. The accumulator 07 releases replenishing oil into the positive cavity 03, resulting in high system damping. In this way, the high-frequency small-amplitude vibration and tremors caused by uneven road surfaces are absorbed by the hydraulic cylinder 02, accumulator 07, etc., providing the vibration reduction capability of the auxiliary support device and improving the ride comfort of the chassis.

[0032] (4) The impact load is distributed to the conventional suspension system and auxiliary support device through the frame 01, and can be jointly borne. At the same time, since the hydraulic cylinder 02 and auxiliary wheel 10 of the auxiliary support device have higher rigidity, they can withstand greater loads, thus improving the overall load-bearing capacity of the vehicle.

[0033] (5) After the impact load is applied, the connection between the oil source and the hydraulic cylinder 02 is restored. Under the action of the power oil source, the reverse chamber 15 of the hydraulic cylinder 02 is filled with oil, and the oil in the positive chamber 03 flows back to the oil source, so that the piston 16 drives the piston rod 09 to quickly retract and lift, the auxiliary wheel 10 is lifted off the ground, and the normal motor state is restored.

[0034] The difference between the dynamically extendable auxiliary support device of this invention and the prior art is that, in use, the outer housing 08 of the actuator (i.e., hydraulic cylinder 02) is fixedly mounted on the frame 01 of a multi-axle special vehicle via a mounting bracket 14. Under normal conditions, when the frame 01 is not subjected to short-term impact loads, the actuator is in an upward retracted state (i.e., the piston rod 09 of the hydraulic cylinder 02 is in an upward retracted state), and the auxiliary wheel 10 is not in contact with the road surface. When it is necessary to withstand short-term impact loads, the actuator is extended downwards (i.e., the piston rod 09 of the hydraulic cylinder 02 extends downwards), and the auxiliary wheel 10 moves downwards under the drive of the actuator until it contacts the road surface. During vehicle travel, the auxiliary wheel 10 can roll along the road surface. In this way, the auxiliary wheel 10 and the actuator can increase the support points for the frame 01, thereby enabling the frame 01 to withstand short-term impact loads. After the short-term impact load disappears, the actuator is retracted upwards again (that is, the piston rod 09 of the hydraulic cylinder 02 is retracted upwards), which drives the auxiliary wheel 10 to move upwards until the auxiliary wheel 10 leaves the road surface. When the auxiliary wheel 10 and the actuator support the frame 01, i.e., when the actuator is in the downward extended state and the auxiliary wheel 10 is in contact with the road surface, the relative movement between the housing 08 and the cylinder is isolated due to the rotary seal structure 18 between the housing 08 and the upper end of the actuator (i.e., the rotary seal structure 18 between the housing 08 and the cylinder of the hydraulic cylinder 02). Therefore, when the housing 08 is subjected to lateral loads from the frame 01, the lateral loads will not be transmitted to the cylinder, thus avoiding the influence of the lateral loads transmitted from the frame 01 on the actuator (hydraulic cylinder 02). Since the lower end of the actuator, i.e., the lower end of the piston rod 09 of the hydraulic cylinder 02, is connected to the auxiliary wheel 10 through the steering knuckle 11, and the steering knuckle 11 can move relative to the lower end of the piston rod 09, the steering knuckle 11 can prevent the influence of the lateral loads transmitted from the auxiliary wheel 10 on the actuator (hydraulic cylinder 02). Thus, the positive and negative chambers 03 and 15 of the actuator (hydraulic cylinder 02) only bear axial loads and not lateral loads. This invention isolates the load-bearing components for lateral and axial loads, making the support device simpler, occupying less space, facilitating modular layout of the chassis, and making the space more compact.

[0035] The aforementioned axial and lateral loads are relative to hydraulic cylinder 02. The load applied along the axial direction of hydraulic cylinder 02 is the axial load, and the load applied along the circumference of hydraulic cylinder 02 is the lateral load. Of course, the load applied radially along hydraulic cylinder 02 is the radial load.

[0036] For the housing 08 and the cylinder of the hydraulic cylinder 02, they are connected by a rotary seal structure 18, meaning they can rotate relative to each other. When a lateral load transmitted from the frame 01 acts on the housing 08, the housing 08 rotates relative to the cylinder under the action of the rotary seal structure 18, meaning the housing 08 will not transmit the lateral load to the cylinder. For the piston rod 09 of the hydraulic cylinder 02, a sleeve 13 is fixedly mounted on the piston rod 09. The sleeve 13 is connected to the auxiliary wheel 10 through a steering knuckle 11. Thus, when a lateral load transmitted from the auxiliary wheel 10 acts on the steering knuckle 11, the steering knuckle 11 rotates relative to the sleeve 13, meaning the steering knuckle 11 will not transmit the lateral load to the sleeve 13, and therefore not to the piston rod 09. It can be seen that the hydraulic cylinder 02 only bears axial loads and not lateral loads.

[0037] Therefore, this invention, installed on the frame 01 of a multi-axle special vehicle, addresses the specific working conditions of multi-axle special vehicles, where the load-bearing range varies significantly, especially when short-term impact loads need to be withstood during movement. It allows the vehicle to meet load-bearing requirements without stopping and even while in motion. It should be noted that the number and location of the auxiliary support devices installed on the vehicle can be determined based on the actual situation.

[0038] Hydraulic cylinder 02, acting as an elastic element, has oil ports in both its positive and negative chambers 03 and 15, connected to the power source, enabling active and controllable extension and retraction. Hydraulic cylinder 02 incorporates a one-way valve 17 and a damping orifice 04. The one-way valve 17 connects the positive chamber 03 to the negative chamber 15, while the negative chamber 15 is isolated from the positive chamber 03. When there is a bump in the road surface, the auxiliary wheel 10 moves upward, and the hydraulic cylinder 02 retracts (i.e., the piston rod 09 moves upward and retracts). Oil in the positive chamber 03 flows into the negative chamber 15 through the one-way valve 17 and the damping orifice 04. Excess oil is pumped into the accumulator 07, resulting in low system damping. When there is a depression in the road surface, the auxiliary wheel 10 moves downward, and the piston rod 09 of hydraulic cylinder 02 extends downward. Oil in the negative chamber 15 can only flow into the positive chamber 03 through the damping orifice 04. The accumulator 07 releases replenishing oil into the positive chamber 03, resulting in high system damping. This achieves a variable damping design for the system. The purpose of adopting the above-mentioned variable damping design is to ensure that when the hydraulic cylinder 02 retracts, that is, when the piston rod 09 retracts, the system damping is small, allowing the hydraulic cylinder 02 to fully absorb the impact energy; and when the hydraulic cylinder 02 extends, that is, when the piston rod 09 extends, the system damping is large, so as to quickly suppress the oscillation generated when the hydraulic cylinder 02 releases energy.

[0039] The accumulator 07, acting as a vibration damping element, can be a diaphragm or piston design. The air chamber 06 is pre-filled with high-pressure gas, and the liquid chamber 05 is connected to the positive chamber 03 of the hydraulic cylinder 02. When the hydraulic cylinder 02 is compressed, excess oil is pumped into the liquid chamber 05; conversely, when the hydraulic cylinder 02 extends and the oil level is insufficient, the oil pressure decreases. Under the pressure of the high-pressure gas in the air chamber 06, the liquid chamber 05 releases replenishing oil into the positive chamber 03. The pre-charge pressure of the air chamber 06 is related to the load-bearing stiffness design; that is, if the load is large, the pre-charged gas pressure in the air chamber 06 should also be large, so that effective load-bearing can be achieved even when the hydraulic cylinder 02 is compressed to a short stroke.

[0040] The cylinder cavity of hydraulic cylinder 02 is a straight cylinder. Since the piston rod 09 is installed in the reverse cavity 15, the cross-sectional area of ​​the reverse cavity 15 is smaller than that of the positive cavity 03. Therefore, when the piston rod 09 retracts upward a certain distance, in addition to a portion of the oil in the positive cavity 03 flowing into and filling the reverse cavity 15, there will be a portion of excess oil, which is then forced into the accumulator 07. When the piston rod 09 extends downward a certain distance, a portion of the oil in the reverse cavity 15 flows into the positive cavity 03, but this is insufficient to compensate for the space freed up by the downward sliding of the piston 16 in the positive cavity 03. Therefore, the oil in the accumulator 07 is added to the positive cavity 03 to fill it.

[0041] The auxiliary support device described above is suitable for short-term, low-frequency application scenarios of special vehicles. It does not require the integration of complex structures such as drive motors, brakes, steering motors, and reducers. The conventional wheels still bear the driving, steering, and braking functions. The device of this invention passively follows, and the steering knuckle 11 is designed to follow the vehicle's steering, which can reduce the complexity of the structural principle and reduce the weight and space of the device.

[0042] Special vehicles using this auxiliary support device can have additional auxiliary support devices added near the location of the impact load. These devices can be located at the rear or the middle of the vehicle, with multiple sets of auxiliary devices working together to provide support. The number of support devices is determined by the load to be borne and the layout.

[0043] Special vehicles using this auxiliary support device retract hydraulic cylinder 02 during normal driving, lifting auxiliary wheel 10 off the ground. Before bearing impact loads, the positive chamber 03 of hydraulic cylinder 02 is pre-filled with oil under the action of the power oil source, causing it to quickly extend and lower during its large stroke, supporting auxiliary wheel 10 on the road surface, allowing it to move with the vehicle. (See attached...) Figure 2 As shown, this is the auxiliary support device in its deployed and ground-supported state. After the impact load, under the action of the power oil source, the hydraulic cylinder 02's reverse chamber 15 is filled with oil, causing it to retract and lift during its large stroke, lifting the auxiliary wheel 10 off the ground and restoring the normal maneuvering state, as shown. Figure 1 As shown.

[0044] The auxiliary support device can be used independently or in combination to meet the load-bearing and connectivity requirements of special vehicles. Multiple hydraulic cylinders (02) can be connected in various ways, such as left-right grouping, front-rear grouping, cross-connection of positive and negative cavities, and overall interconnection, to meet the load-bearing needs of different loads and working conditions.

[0045] The beneficial effects of this invention are as follows: (1) The auxiliary support device proposed in this invention can solve the problem of bearing short-term impact loads, optimize the overall design of multi-axle special vehicles, assist conventional suspension systems in bearing large tonnage loads, and eliminate the need for state transition measures such as stopping or lowering outriggers, as well as the need to add conventional tires to make the overall vehicle too large. This invention does not affect the maneuverability of multi-axle vehicles and can be implemented dynamically and actively during maneuvering, thereby improving the maneuverability and load-bearing flexibility of multi-axle vehicles.

[0046] (2) The auxiliary support device proposed in this invention integrates elastic elements, damping elements, housing 08, sleeve 13, etc., and isolates the load-bearing components for lateral loads and axial loads. The device adopts a modular design, has a high degree of integration, a simpler structure, occupies less space, and facilitates modular layout of the chassis, making the space more compact.

[0047] (3) The auxiliary support device proposed in this invention adopts a structure of hydraulic cylinder 02 + steering knuckle 11 + auxiliary wheel 10, which is different from the traditional suspension design. The traditional suspension also integrates drive motor, brake, steering motor, reducer, etc. in the lower part, which is complex in structure and principle, and has a large weight and space. However, the auxiliary support device of this invention is only used for a short time and infrequently, and does not need to integrate drive motor, brake, steering motor, reducer, etc. The conventional wheels still bear the driving, steering and braking functions. The device of this invention passively follows, and the steering knuckle 11 is designed to follow the vehicle's steering, reducing the complexity of the structural principle, reducing the weight and space of the device, etc., and facilitating modular design and layout in the limited space of the vehicle.

[0048] (4) The auxiliary wheel 10 proposed in this invention is not an ordinary pneumatic tire. In order to withstand the transmission of instantaneous large tonnage loads, and with the requirement of small weight and size and sufficient space for folding and unfolding, it can adopt special designs such as high-strength aviation tires, solid tires, metal tires, composite structure tires, and tires with built-in support frames. It has high load-bearing capacity and small size, and can be arranged between the conventional tires of special vehicles. It is convenient for modular design and layout in the limited space of the vehicle, and can be folded and unfolded with a large stroke. The auxiliary wheel 10 can be arranged as a single tire or as a dual tire arrangement mounted on the same axle, further improving the load-bearing capacity.

[0049] (5) The auxiliary support device proposed in this invention does not need to be supported on the ground for a long time, but can adjust the extension length over a long range to retract and lower the auxiliary wheel 10 large stroke lifting wheel.

[0050] Assuming the impact load center of a multi-axle special vehicle is located at the rear of the vehicle, this will be used as an example for illustration. It is assumed that calculations show that one set of auxiliary support devices is needed at each of the four positions (front, rear, left, and right) to jointly bear the load at the impact load center, for a total of four sets. Each support device's auxiliary wheel 10 is assumed to be a single tire.

[0051] The working process of this support device in multi-axle vehicles is as follows: ① When the vehicle is driving under normal operating conditions, it is supported by the conventional suspension system and wheels. All auxiliary support devices are retracted, and the auxiliary wheels 10 are lifted off the ground and do not bear any load. Of course, at this time, the positive chamber 03 and the negative chamber 15 of all hydraulic cylinders 02 are connected to the oil source and are filled with high-pressure oil.

[0052] ② Before being subjected to a short-term, high-tonnage impact load, under the action of the power oil source, oil is supplied to the positive chamber 03 of each hydraulic cylinder 02, and the oil in the negative chamber 15 flows back to the oil source, causing it to extend and lower rapidly during its large stroke. The auxiliary wheel 10 is supported on the road surface and moves with the vehicle. At this time, the conventional wheels still bear the functions of driving, steering, and braking. By cutting off the connection between the oil source and the hydraulic cylinder 02, the auxiliary support device described in this invention passively follows, and the steering knuckle 11 is designed to follow the vehicle's steering.

[0053] ③ When the vehicle is in motion, uneven road surfaces can cause the auxiliary wheel 10 to bounce up or down. When there is a bump in the road surface, the auxiliary wheel 10 moves upward, the hydraulic cylinder 02 contracts, and the oil in the positive cavity 03 flows into the negative cavity 15 through the one-way valve 17 and the damping hole 04. Excess oil is pumped into the accumulator 07, resulting in low system damping. When there is a depression in the road surface, the auxiliary wheel 10 moves downward, the hydraulic cylinder 02 extends, and the oil in the negative cavity 15 can only flow into the positive cavity 03 through the damping hole 04. The accumulator 07 releases replenishing oil into the positive cavity 03, resulting in high system damping. In this way, the high-frequency, low-amplitude vibrations and tremors caused by uneven road surfaces are absorbed by the hydraulic cylinder 02, accumulator 07, etc., improving the system's vibration damping capability and chassis ride comfort.

[0054] ④ Each hydraulic cylinder 02 is grouped or connected in series as needed to improve load-bearing capacity. Impact loads are distributed to the conventional suspension system and various auxiliary support devices via the frame 01, allowing them to be borne collectively. Simultaneously, due to the higher rigidity of the hydraulic cylinders 02 and auxiliary wheels 10 in the auxiliary support devices, they can withstand greater loads, thus improving the overall load-bearing capacity of the vehicle.

[0055] ⑤ After the impact load is applied, the connection between the oil source and the hydraulic cylinder 02 is restored. Under the action of the power oil source, the reverse chamber 15 of the hydraulic cylinder 02 is filled with oil, and the oil in the positive chamber 03 flows back to the oil source, so that its large stroke is quickly contracted and lifted, the auxiliary wheel 10 is lifted off the ground, and the normal motor state is restored.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A dynamically retractable auxiliary support device, characterized in that: It includes an actuator capable of vertical extension and retraction, with a housing fitted around the upper outer side of the actuator, a rotary sealing structure between the housing and the upper end of the actuator, and an auxiliary wheel connected to the lower end of the actuator via a steering knuckle.

2. The dynamically retractable auxiliary support device according to claim 1, characterized in that: The actuator is a hydraulic cylinder with the piston on top and the piston rod facing downward. A cylindrical shell is fitted around the cylinder barrel of the hydraulic cylinder, and a rotary sealing structure is provided between the shell and the cylinder barrel of the hydraulic cylinder. An auxiliary wheel is connected to the lower end of the piston rod of the hydraulic cylinder through a steering knuckle.

3. The dynamically retractable auxiliary support device according to claim 2, characterized in that: The cylinder chamber of the hydraulic cylinder is divided by a piston into an upper positive chamber and a lower negative chamber. Both the positive and negative chambers can be connected to an oil source, and the positive chamber is connected to an accumulator.

4. The dynamically retractable auxiliary support device according to claim 3, characterized in that: The piston is provided with a one-way valve that connects the positive cavity to the negative cavity and isolates the negative cavity from the positive cavity. The piston is also provided with a damping orifice that connects the positive cavity and the negative cavity.

5. The dynamically retractable auxiliary support device according to claim 4, characterized in that: A sleeve is fixedly fitted on the outer side of the lower end of the piston rod. The sleeve is connected to the steering knuckle, and the steering knuckle is connected to the auxiliary wheel.

6. The dynamically retractable auxiliary support device according to claim 2, characterized in that: The outer side of the housing is fixedly provided with a mounting bracket for fixed connection with the vehicle frame.

7. The dynamically retractable auxiliary support device according to claim 2, characterized in that: The auxiliary wheel is an aircraft tire, a solid tire, a metal tire, a composite structure tire, or a tire with an internal support frame.

8. The dynamically retractable auxiliary support device according to claim 7, characterized in that: The auxiliary wheels are arranged with a single tire.

9. The dynamically retractable auxiliary support device according to claim 7, characterized in that: The auxiliary wheel is arranged coaxially with dual tires.

10. The dynamically retractable auxiliary support device according to claim 3, characterized in that: The accumulator is a diaphragm accumulator or a piston accumulator, and the accumulator includes a liquid chamber and a gas chamber, with the positive chamber connected to the liquid chamber of the accumulator.

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