Four-wheel steering device of fire fighting truck

Abstract

The invention relates to a four-wheel steering device of a fire fighting truck, which comprises a frame, a steering driving mechanism connected with the frame and used for providing steering driving force; the steering control mechanism is connected with the steering driving mechanism; the Ackerman steering mechanism comprises a first steering mechanism and a second steering mechanism which are arranged on the frame; and the steering transmission mechanism comprises a first steering connecting rod of which one end is rotationally connected with the first steering mechanism, a second steering connecting rod of which one end is rotationally connected with the second steering mechanism, and a telescopic rod assembly which is rotationally connected with the other end of the first steering connecting rod and the other end of the second steering connecting rod. The four-wheel steering device of the fire fighting truck is simple in structure, the turning radius can be obviously reduced, meanwhile, steering can be dynamically adjusted according to the real-time road surface state, various road surfaces can be effectively handled, the maneuverability and flexibility of the fire fighting truck in a lower gate space are improved, and therefore the rescue efficiency of the fire fighting truck is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of fire trucks, and more particularly to a four-wheel steering device for fire trucks. Background Art

[0002] In modern urban rescue, fire trucks often need to perform emergency tasks in narrow areas such as tunnels. However, the space limitations in these areas pose a huge challenge to the steering and movement of fire trucks. Traditional fire trucks mainly rely on front-wheel steering, which may be sufficient on open roads, but in narrow and winding tunnel environments, it seems inadequate. Due to the limitation of the turning radius, fire trucks often find it difficult to complete steering quickly and accurately, which not only affects the efficiency of rescue, but may also cause greater losses due to delays.

[0003] At present, although the manufacturing technology of fire trucks is constantly improving, there is still a lack of breakthrough solutions for the specific problem of steering in narrow areas. Although the existing steering systems of fire trucks have been optimized to a certain extent, they are still stretched when facing extremely narrow environments. Most of these systems fail to fully consider the dynamic steering requirements in specific scenarios such as tunnels, resulting in insufficient flexibility and slow response in actual operations.

[0004] Specifically, the limitations of existing technologies are mainly reflected in the following aspects: first, the turning radius is still large, making it difficult to adapt to extremely narrow spaces; second, it lacks intelligent adjustment functions and is unable to dynamically adjust steering strategies according to real-time environments; third, in some extreme cases, there may even be an embarrassing situation where steering is impossible, seriously affecting the smooth progress of rescue work. Summary of the invention

[0005] The present invention aims to overcome at least one defect of the above-mentioned prior art and provide a four-wheel steering device for a fire truck, which is used to solve the problems of the prior art fire trucks having difficulty in turning in narrow areas, insufficient steering flexibility and slow response.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A four-wheel steering device for a fire truck, comprising:

[0008] The frame, used to provide support;

[0009] A steering drive mechanism, connected to the vehicle frame, for providing a steering drive force;

[0010] A steering control mechanism, connected to the steering drive mechanism, for converting the driving force into a swing of the Ackerman steering mechanism;

[0011] An Ackerman steering mechanism, comprising a first steering mechanism and a second steering mechanism arranged on a vehicle frame, wherein the first steering mechanism is connected to the steering control mechanism, and both the first steering mechanism and the second steering mechanism satisfy the Ackerman steering principle;

[0012] A steering transmission mechanism is used to connect the first steering mechanism and the second steering mechanism, including a first steering connecting rod with one end rotatably connected to the first steering mechanism, a second steering connecting rod with one end rotatably connected to the second steering mechanism, and a telescopic rod assembly rotatably connected to the other end of the first steering connecting rod and the other end of the second steering connecting rod.

[0013] In one embodiment, the first steering mechanism and the second steering mechanism have the same structure and are arranged in a mirror image on the frame.

[0014] In one embodiment, the first steering mechanism includes a cross bridge connected to the vehicle frame, wheel hub fixing frames arranged at both ends of the cross bridge, two sets of steering knuckle arms respectively connected to the wheel hub fixing frames at both ends, and a knuckle arm long connecting rod rotatably connecting the two sets of steering knuckle arms; the wheel hub fixing frame at one end is connected to the steering control mechanism.

[0015] In one embodiment, the cross bridge is arranged in an axisymmetric arch structure.

[0016] In one embodiment, the first steering connecting rod is rotatably connected to the first wheel hub fixing frame on one side of the first steering mechanism through a first wheel hub connecting bracket; the second steering connecting rod is rotatably connected to the second wheel hub fixing frame on the other side of the second steering mechanism through a second wheel hub connecting bracket; wherein the first wheel hub fixing frame and the second wheel hub fixing frame are in a diagonal relationship.

[0017] In one embodiment, the telescopic rod assembly includes a telescopic connecting rod, and a first steering block and a second steering block respectively arranged at both ends of the telescopic connecting rod, the first steering block is rotatably connected to the first steering connecting rod, and the second steering block is rotatably connected to the second steering connecting rod.

[0018] In one embodiment, the first steering connecting rod and the second steering connecting rod have the same length, and the ratio of the length of the first steering connecting rod to the length of the telescopic rod is in the range of 0.5 to 0.9.

[0019] In one embodiment, the first steering block and the second steering block have the same structure and are arranged in a triangular block.

[0020] In one embodiment, the steering control mechanism includes an active rocker connected to the output end of the steering drive mechanism, a rotation control link rotationally connected to the active rocker, and a transverse rocker rotationally connected to the rotation control link; the transverse rocker is rotationally connected to the first wheel hub connecting bracket.

[0021] In one embodiment, the first wheel hub connecting bracket is arranged at the upper end of the first wheel hub fixing frame, and the steering knuckle arm is arranged at the lower end of the first wheel hub fixing frame.

[0022] Compared with the prior art, the beneficial effects of the present invention include at least:

[0023] The four-wheel steering device of the fire truck of the technical solution is not only simple in structure, but also can significantly reduce the turning radius. At the same time, it can dynamically adjust the steering according to the real-time road surface state, effectively cope with various types of road surfaces, improve the maneuverability and flexibility of the fire truck in the lower gate space, and effectively improve the rescue efficiency of the fire truck. Specifically, the technical solution drives the steering control mechanism to move through the steering drive mechanism, thereby providing power for the Ackerman steering mechanism, and converts the driving force into the swing of the first steering mechanism. The two ends of the first steering mechanism and the two ends of the second steering mechanism are respectively connected to the wheels; because the first steering mechanism and the second steering mechanism both meet the Ackerman steering principle, that is, the turning angle of the inner wheel is greater than that of the outer wheel, so that the vertical line of all the wheels of the fire truck can point to the center of the circle, so that the steering posture of the fire truck is smoother and more stable. At the same time, the technical solution transmits the steering power of the first steering mechanism, i.e., the front wheel, to the second steering mechanism, i.e., the rear wheel, through the steering transmission mechanism. When the first steering mechanism swings, it drives the first steering connecting rod to move, and the movement of the first steering connecting rod drives the telescopic rod assembly to telescope and transform, and at the same time makes the second steering connecting rod move in the opposite direction, driving the second steering mechanism to move, realizing four-wheel steering, and effectively reducing the turning radius. In addition, by setting up a telescopic rod assembly, dynamic telescopic extension and retraction can be achieved during the steering process, which can adapt to the weight of the fire truck and different road conditions. The telescopic rod assembly effectively transmits the load, increases the strength, and ensures that the steering movement can be correctly and stably transmitted to the second steering mechanism, while also improving the service life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of the four-wheel steering device for a fire truck of the present invention.

[0025] Figure 2 It is a schematic structural diagram of the first steering mechanism of the present invention.

[0026] Figure 3 It is a structural schematic diagram of the steering transmission mechanism of the present invention.

[0027] Figure 4It is a structural schematic diagram of the steering drive mechanism and the steering control mechanism of the present invention.

[0028] 10. Frame; 20. Steering drive mechanism; 30. Steering control mechanism; 31. Active rocker; 32. Rotation control link; 33. Transverse rocker; 34. Link extension column; 35. Rocker rotation base; 40. Ackerman steering mechanism; 41. First steering mechanism; 411. Cross bridge; 412. Hub fixing frame; 413. Steering knuckle arm; 414. Knuckle arm long link; 415. First hub connecting bracket; 416. Knuckle arm fixing column; 42. Second steering mechanism; 50. Steering transmission mechanism; 51. First steering connecting rod; 52. Second steering connecting rod; 53. Telescopic rod assembly; 531. Telescopic connecting rod; 532. First steering block; 533. Second steering block. DETAILED DESCRIPTION

[0029] The drawings of the present invention are only for illustrative purposes and should not be construed as limiting the present invention. In order to better illustrate the following embodiments, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; it is understandable to those skilled in the art that some well-known structures and their descriptions in the drawings may be omitted.

[0030] like Figure 1-Figure 4 A four-wheel steering device for a fire truck shown in the figure comprises:

[0031] A frame 10, used to provide support;

[0032] A steering drive mechanism 20, connected to the vehicle frame 10, for providing a steering drive force;

[0033] A steering control mechanism 30 connected to the steering drive mechanism 20 and used for converting the driving force into the swing of the Ackerman steering mechanism 40;

[0034] An Ackerman steering mechanism 40, comprising a first steering mechanism 41 and a second steering mechanism 42 arranged on the frame 10, wherein the first steering mechanism 41 is connected to the steering control mechanism 30, and both the first steering mechanism 41 and the second steering mechanism 42 satisfy the Ackerman steering principle;

[0035] The steering transmission mechanism 50 is used to connect the first steering mechanism 41 and the second steering mechanism 42, including a first steering connecting rod 51 having one end rotatably connected to the first steering mechanism 41, a second steering connecting rod 52 having one end rotatably connected to the second steering mechanism 42, and a telescopic rod assembly 53 rotatably connected to the other end of the first steering connecting rod 51 and the other end of the second steering connecting rod 52.

[0036] The four-wheel steering device of the fire truck of this embodiment is not only simple in structure, but also can significantly reduce the turning radius. At the same time, it can dynamically adjust the steering according to the real-time road surface state, effectively cope with various types of road surfaces, and improve the maneuverability and flexibility of the fire truck in the lower gate space, thereby effectively improving the rescue efficiency of the fire truck. Specifically, in this embodiment, the steering control mechanism 30 is driven to move by the steering drive mechanism 20, thereby providing power for the Ackerman steering mechanism 40, and converting the driving force into the swing of the first steering mechanism 41, and the two ends of the first steering mechanism 41 and the two ends of the second steering mechanism 42 are respectively connected to the wheels; because the first steering mechanism 41 and the second steering mechanism 42 both meet the Ackerman steering principle, that is, the turning angle of the inner wheel is greater than that of the outer wheel, so that the vertical lines of all the wheels of the fire truck can point to the center of the circle, making the steering posture of the fire truck smoother and more stable. At the same time, this embodiment transmits the steering power of the first steering mechanism 41, i.e., the front wheel, to the second steering mechanism 42, i.e., the rear wheel, through the steering transmission mechanism 50. When the first steering mechanism 41 swings, it drives the first steering connecting rod 51 to move. The movement of the first steering connecting rod 51 drives the telescopic rod assembly 53 to telescope and transform, and at the same time, the second steering connecting rod 52 moves in the opposite direction, driving the second steering mechanism 42 to move, thereby realizing four-wheel steering and effectively reducing the turning radius. In addition, by setting the telescopic rod assembly 53, dynamic telescopic expansion and contraction can be realized during the steering process, which can adapt to the weight of the fire truck and different road conditions. The telescopic rod assembly 53 effectively transmits the load, increases the strength, ensures that the steering movement can be correctly and stably transmitted to the second steering mechanism 42, and also improves the service life of the device.

[0037] In this embodiment, the first steering mechanism 41 and the second steering mechanism 42 have the same structure, which reduces the difficulty of workpiece processing and assembly, and the first steering mechanism 41 and the second steering mechanism 42 are mirror-imaged along the length direction of the frame 10, and the spacing distance between the first steering mechanism 41 and the second steering mechanism 42 is positively correlated with the length of the frame 10.

[0038] like Figure 2As shown, the first steering mechanism 41 of this embodiment includes a cross bridge 411 connected to the vehicle frame 10, a wheel hub fixing frame 412 provided at both ends of the cross bridge 411, two sets of steering knuckle arms 413 respectively connected to the wheel hub fixing frames 412 at both ends, and a knuckle arm long connecting rod 414 rotatably connecting the two sets of steering knuckle arms 413; the wheel hub fixing frame 412 at one end is connected to the steering control mechanism 30. Through this arrangement, not only is the structure simple and the assembly is convenient, but also the first steering mechanism 41 satisfies the Ackerman steering principle. When the steering drive mechanism 20 drives the wheel hub fixing frame 412 connected thereto to swing, the steering knuckle arm 413 connected to the corresponding wheel hub fixing frame 412 swings, driving the knuckle arm long connecting rod 414 to move, thereby causing the steering knuckle arm 413 at the other end to swing, driving the wheel hub fixing frame 412 at the other end to swing, ensuring that when the fire truck is turning, there is a certain difference in the steering angle between the inner wheel and the outer wheel, that is, while meeting the Ackerman angle, the steering stability is guaranteed and the tire wear is reduced.

[0039] Specifically, two sleeves are arranged at both ends of the cross bridge 411 of this embodiment, and bearings are arranged inside the sleeves to reduce friction, which are used to connect with the hub fixing frame 412, and the rotating shaft of the hub fixing frame 412 can rotate in the sleeve. The hub fixing frame 412 is provided with a hub positioning hole to facilitate the installation and disassembly of the tire.

[0040] The cross bridge 411 described in this embodiment is arranged in an axisymmetric arch structure, and the axis of symmetry coincides with the axis of symmetry of the frame 10, thereby enhancing the strength of the cross bridge 411, improving the bending resistance, preventing fatigue damage, and extending the service life of the product.

[0041] like Figure 3 As shown, in this embodiment, the first steering connecting rod 51 is rotatably connected to the first hub fixing frame on one side of the first steering mechanism 41 through the first hub connecting bracket 415, and the first hub fixing frame is connected to the steering control mechanism 30 through the first hub connecting bracket 415; the second steering connecting rod 52 is rotatably connected to the second hub fixing frame on the other side of the second steering mechanism 42 through the second hub connecting bracket; wherein, the first hub fixing frame and the second hub fixing frame are in a diagonal relationship. The first hub connecting bracket 415 and the second hub connecting bracket are respectively fixed to the upper ends of the first hub fixing frame and the second hub fixing frame through threads. When the first steering mechanism 41 undergoes a steering movement, the first hub connecting bracket 415 rotates accordingly, thereby driving the first steering connecting rod 51 to move forward and backward, and at this time driving the telescopic rod assembly 53 to perform telescopic transformation, thereby driving the second steering connecting rod 52 to move forward and backward, and finally transmitting the movement to the second hub fixing frame, driving the second steering mechanism 42 to undergo a steering movement.

[0042] The telescopic rod assembly 53 of this embodiment includes a telescopic telescopic connecting rod 531, and a first steering block 532 and a second steering block 533 respectively arranged at both ends of the telescopic connecting rod 531, wherein the first steering block 532 is rotationally connected to the first steering connecting rod 51, and the second steering block 533 is rotationally connected to the second steering connecting rod 52. Specifically, when the first steering mechanism 41 makes a steering movement, the first wheel hub connecting bracket 415 rotates accordingly, thereby driving the first steering connecting rod 51 to move forward (or backward), and at this time, the first steering block 532 connected to the first steering connecting rod 51 rotates accordingly, and the generated rotation further drives the telescopic connecting rod 531 to telescope, so that the second steering block 533 also rotates in the opposite direction of the first steering block 532, and drives the second steering connecting rod 52 to move backward (or forward) in the opposite direction of the first steering connecting rod 51, and finally the steering movement is transferred to the second wheel hub fixing frame through the first wheel hub connecting bracket 415 to make it swing, driving the second steering mechanism 42 to make a steering movement, and completing the steering control of the rear wheel.

[0043] In this embodiment, the first steering connecting rod 51 and the second steering connecting rod 52 have the same length, and the ratio of the length of the first steering connecting rod 51 to the length of the telescopic rod is in the range of 0.5 to 0.9. This setting can effectively transmit the load and ensure that the steering movement can be correctly and stably transmitted to the second steering mechanism 42.

[0044] In this embodiment, the first steering block 532 and the second steering block 533 have the same structure and are arranged in a triangular block, which has higher strength, more stable rotational motion transmission, and is less likely to shake, further ensuring the reliability of the steering motion.

[0045] like Figure 4 As shown, the steering control mechanism 30 includes an active rocker 31 connected to the output end of the steering drive mechanism 20, a rotation control link 32 rotationally connected to the active rocker 31, and a transverse rocker 33 rotationally connected to the rotation control link 32; the transverse rocker 33 is rotationally connected to the first hub connection bracket 415. Specifically, the transverse rocker 33 is connected to the rotation control link 32 through a link extension column 34, and the rotation control link 32 is also connected to the active rocker 31 through another link extension column 34. The active rocker 31 is fixed on the rocker rotating base 35. The output end of the steering drive mechanism 20 controls the rocker rotating base 35 to control the active rocker 31 to swing, so that the motion is transmitted through the rotation control link 32 and the transverse rocker 33, and finally the hub fixing frame 412 is controlled to swing, driving the first steering mechanism 41 to move, and completing the steering control of the front wheel.

[0046] In this embodiment, the first wheel hub connection bracket 415 is arranged at the upper end of the first wheel hub fixing frame, and the steering knuckle arm 413 is arranged at the lower end of the first wheel hub fixing frame. The first wheel hub connection bracket 415 of this embodiment serves as an intermediate fulcrum connecting the transverse rocker 33 and the first steering connecting rod 51, and the two share the same first wheel hub connection bracket 415, which saves assembly space, reduces the number of workpieces, and facilitates assembly. At the same time, the first wheel hub connection bracket 415 and the steering knuckle arm 413 are respectively arranged at the upper and lower ends of the wheel hub fixing frame 412, thereby avoiding interference between the two groups of motion, and ensuring smooth transmission of the steering motion.

[0047] Specifically, connecting end blocks are provided at both upper and lower ends of the rotating shaft of the wheel hub fixing frame 412, one end of the steering knuckle arm 413 is connected to the connecting end block at the lower end of the rotating shaft of the first wheel hub fixing frame, and the other end of the steering knuckle arm 413 is provided with a mounting hole for a knuckle arm fixing column 416, and a bearing is provided in the mounting hole to reduce friction, and is rotatably connected to the knuckle arm long connecting rod 414 through the knuckle arm fixing column 416.

[0048] The steering drive mechanism 20 of this embodiment is a drive motor, and the output end of the drive motor is connected to the rocker rotating base 35 .

[0049] The four-wheel steering device of the fire truck in this embodiment significantly improves the trafficability and flexibility of the vehicle in narrow environments. Compared with the traditional front-wheel steering system, the four-wheel steering system can significantly reduce the turning radius when the vehicle turns, so that the fire truck can turn in a very limited space. Especially in narrow areas such as tunnels, the fire truck can turn around on the spot or perform complex steering operations, so as to reach the rescue site more efficiently and reduce rescue delays caused by inflexible operations.

[0050] In addition, this embodiment effectively improves the steering accuracy and stability of the vehicle by optimizing the design of the steering angle and the steering mechanism, and can reasonably adjust the steering angles of the inner and outer tires when the vehicle turns, meeting the Ackerman steering geometry principle. This design not only ensures the stability of the fire truck in complex environments, but also reduces tire wear and extends the service life of the tires.

[0051] This embodiment adopts an advanced steering control mechanism 30, an Ackerman steering mechanism 40 and a steering transmission mechanism 50, and uses a single motor to drive the steering, thereby reducing the complexity of the operation. The steering control mechanism 30 converts the rotational motion of the motor into the swing of the wheel hub through an efficient transmission mechanism, making the steering response of the vehicle more sensitive and accurate. This design simplifies the operation process, enables operators to more easily cope with various complex environments, and improves the convenience and efficiency of operation during the rescue process.

[0052] The four-wheel steering device of the fire truck of this embodiment has superior performance in narrow spaces and on different road surfaces, enabling the fire truck to reach the scene of the incident faster and more accurately for emergency rescue. This efficient steering system not only shortens the rescue time, but also provides more flexible maneuverability at critical moments, thereby greatly improving the overall rescue efficiency and providing strong protection for urban emergency rescue.

[0053] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the technical solution of the present invention, and are not intended to limit the specific implementation methods of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the claims of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. The four-wheel steering device of a fire truck is characterized by: include: The frame, used to provide support; A steering drive mechanism, connected to the vehicle frame, for providing a steering drive force; A steering control mechanism, connected to the steering drive mechanism, for converting the driving force into a swing of the Ackerman steering mechanism; An Ackerman steering mechanism, comprising a first steering mechanism and a second steering mechanism arranged on a vehicle frame, wherein the first steering mechanism is connected to the steering control mechanism, and both the first steering mechanism and the second steering mechanism satisfy the Ackerman steering principle; A steering transmission mechanism is used to connect the first steering mechanism and the second steering mechanism, including a first steering connecting rod with one end rotatably connected to the first steering mechanism, a second steering connecting rod with one end rotatably connected to the second steering mechanism, and a telescopic rod assembly rotatably connected to the other end of the first steering connecting rod and the other end of the second steering connecting rod.

2. The four-wheel steering device for a fire truck according to claim 1, characterized in that: The first steering mechanism and the second steering mechanism have the same structure and are arranged on the frame in a mirror image.

3. The four-wheel steering device for a fire truck according to claim 2, characterized in that: The first steering mechanism includes a cross bridge connected to the vehicle frame, wheel hub fixing frames arranged at both ends of the cross bridge, two groups of steering knuckle arms respectively connected to the wheel hub fixing frames at both ends, and a knuckle arm long connecting rod rotatably connecting the two groups of steering knuckle arms; the wheel hub fixing frame at one end is connected to the steering control mechanism.

4. The four-wheel steering device for a fire truck according to claim 3, characterized in that: The cross bridge is arranged in an axisymmetric arch structure.

5. The four-wheel steering device for a fire truck according to claim 3, characterized in that: The first steering connecting rod is rotatably connected to the first wheel hub fixing frame on one side of the first steering mechanism through the first wheel hub connecting bracket; the second steering connecting rod is rotatably connected to the second wheel hub fixing frame on the other side of the second steering mechanism through the second wheel hub connecting bracket; wherein the first wheel hub fixing frame and the second wheel hub fixing frame are in a diagonal relationship.

6. The four-wheel steering device for a fire truck according to any one of claims 1 to 5, characterized in that: The telescopic rod assembly includes a telescopic connecting rod, and a first steering block and a second steering block respectively arranged at both ends of the telescopic connecting rod, the first steering block is rotatably connected to the first steering connecting rod, and the second steering block is rotatably connected to the second steering connecting rod.

7. The four-wheel steering device for a fire truck according to claim 6, characterized in that: The first steering connecting rod and the second steering connecting rod have the same length, and the ratio of the length of the first steering connecting rod to the length of the telescopic rod is in the range of 0.5 to 0.

9.

8. The four-wheel steering device for a fire truck according to claim 6, characterized in that: The first steering block and the second steering block have the same structure and are arranged in a triangular block.

9. The four-wheel steering device for a fire truck according to claim 5, characterized in that: The steering control mechanism includes an active rocker connected to the output end of the steering drive mechanism, a rotation control link rotationally connected to the active rocker, and a transverse rocker rotationally connected to the rotation control link; the transverse rocker is rotationally connected to the first wheel hub connecting bracket.

10. The four-wheel steering device for a fire truck according to claim 9, characterized in that: The first wheel hub connecting bracket is arranged at the upper end of the first wheel hub fixing frame, and the steering knuckle arm is arranged at the lower end of the first wheel hub fixing frame.

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