Steering system of milling machine
By adopting a four-wheel/track coordinated steering mode, the problems of difficult steering of the rear wheels and track wear of the milling machine are solved, resulting in a smaller turning radius and greater flexibility, and extending the service life of the tracks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-21
- Publication Date
- 2026-03-27
AI Technical Summary
Existing milling machines have difficulty steering with their rear wheels, have a large turning radius, and their tracks are prone to wear, making it difficult to meet the flexibility requirements of narrow road sections.
It adopts a four-wheel/track coordinated steering mode, which uses the independent rotation of the right and left rear tires/tracks in conjunction with the front wheel/track steering to achieve the forward shift of the instantaneous center of speed, reduce the turning radius, and ensure that the track rolls purely during the steering process through the control of the front steering tie rod and the right rear outrigger cantilever, thereby reducing wear.
It improves the flexibility and maneuverability of the milling machine in narrow passages, extends the service life of the tracks, and enhances the overall maneuverability of the vehicle.
Smart Images
Figure CN121734504A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a milling machine steering system, belonging to the technical field of engineering machinery. BACKGROUND
[0002] The pavement milling machine is a special mechanical equipment for highway and urban road maintenance operation, mainly applied to the excavation and repair of asphalt concrete surface layer of highways, airports, wharfs and parking lots, and the removal of rutting, cracking, acne and road marking of asphalt pavement, and the milling of roughness and surface layer of cement pavement.
[0003] The rear milling machine of the working device is difficult to realize steering due to the short distance between the milling chamber and the tire / track, so the front wheel steering is mainly used for this type of milling machine. In order to balance the wear of the tire / track, the speed centroid of the whole machine during steering is distributed near the axis of the rear wheel / track, which leads to a large turning radius. Because the main working condition of this type of milling machine includes small areas and narrow road sections, the flexibility of the whole vehicle is required to be high, and the current mainstream steering mode is difficult to meet the working condition requirements.
[0004] In order to improve the working adaptability of the milling machine and the operability of the operator, the present application proposes a new mode of four-wheel / track cooperative steering, which realizes the forward movement of the speed centroid by the independent rotation of the right rear and left rear tires / track and the steering of the front wheel / track, so as to reduce the turning radius and improve the flexibility and operability of the whole vehicle. SUMMARY
[0005] The problem solved by the present application is that the rear wheel is difficult to realize steering, the turning radius is large, and the track is easy to wear in the prior art.
[0006] To solve the above technical problems, the present application adopts the following technical scheme.
[0007] The present application provides a milling machine steering system, comprising steering traction units respectively arranged on the left front side, the right front side, the left rear side and the right rear side of the vehicle frame, the steering traction units are respectively connected with walking track units, a front connecting piece is arranged between the two steering traction units on the front side, at least one steering traction unit on the rear side is connected with a rear connecting piece, at least one walking track unit on the rear side is connected with a limiting device, and a driving device is arranged between the steering traction units and the walking track units.
[0008] The rear connecting piece drives the corresponding steering traction units to switch between the first position and the second position, when the steering traction units are in the first position, the right front walking track and the left front walking track corresponding to the right front steering traction unit and the left front steering traction unit rotate, and when the steering traction units are in the second position, the four walking tracks corresponding to the steering traction units rotate.
[0009] A new mode of four-track coordinated steering is proposed. When the front drive mechanism works, the speed centroid of the whole vehicle is near the axis of the right front walking track and the left front walking track, so as to ensure that the four tracks make pure rolling during steering, reduce the wear of the track plate, and improve the service life. When the four-wheel drive mechanism works, the speed centroid moves forward, which reduces the turning radius and improves the flexibility of the whole vehicle in narrow passages, and improves the maneuverability of the equipment.
[0010] The front connecting piece is a front steering pull rod, which is connected between the right front steering traction unit and the left front steering traction unit. The front steering pull rod controls the right front steering traction unit, the left front steering traction unit, the right front walking track and the left front walking track through an oil cylinder.
[0011] The rotation of the track is controlled by the front steering pull rod. During the rotation, the deflection angles of the tracks on the left and right sides are different, so that a smaller turning radius can be better achieved.
[0012] The rear connecting piece is a right rear leg cantilever, which is connected with the right rear steering traction. The swing of the right rear cantilever controls the steering of the right rear walking track.
[0013] The swing of the right rear leg cantilever and the coupled motion of the right rear walking track can realize the swing in and out of the right rear leg cantilever during the movement of the milling machine.
[0014] The first position is that the right rear leg cantilever swings out, the right rear steering traction is located on the outside, and the right front walking track, the left front walking track and the left rear walking track are steered.
[0015] The second position is that the right rear leg cantilever swings in, the right rear steering traction is located on the inside, and the right front walking track, the left front walking track, the right rear walking track and the left rear walking track are steered.
[0016] By controlling the swing of the right rear leg cantilever and the steering of the track, the right rear walking track can realize a steering angle of ±10°.
[0017] The limiting device is installed on the right rear walking track and the left rear walking track, wherein the limiting device includes a limiting bolt and a limiting block. The limiting block is installed on one side of the left rear walking track, and a group of limiting bolts are arranged on both sides below the limiting block. The limiting bolts are installed at both ends of the left rear steering traction unit.
[0018] The drive unit includes a right rear steering cylinder, a right rear swing cylinder, and a left rear steering cylinder. The right rear steering cylinder is connected to the right rear steering traction unit. The right rear track drives the left rear track to turn through the right rear swing cylinder. The left rear steering cylinder is connected to the left rear steering traction unit.
[0019] The left rear steering cylinder pushes the left rear steering traction to drive the left rear travel track to rotate, with a steering angle of ±10°. When the left rear travel track reaches the turning angle limit, the limit bolt contacts the limit block.
[0020] The contact between the limit bolt and the limit block can avoid the risk of interference between the left rear track and other components.
[0021] The right rear support leg cantilever is provided with a pivot at one end, and the right rear support leg cantilever is hinged to the vehicle frame through the pivot.
[0022] Beneficial effects
[0023] This invention proposes a novel four-track coordinated steering mode. When the right rear outrigger is extended, the vehicle's steering motion is primarily achieved through the steering of the right and left front traveling tracks. The instantaneous center of the vehicle's steering speed is near the axis of the right and left front traveling tracks, ensuring that all four tracks perform pure rolling during steering, reducing track wear and extending service life. When the right rear outrigger is engaged, all four tracks can perform steering operations. The rotation of the right and left rear traveling tracks, combined with the steering of the right and left front traveling tracks, shifts the instantaneous center of speed forward, thereby reducing the turning radius, improving the vehicle's flexibility in narrow passages, and enhancing the equipment's maneuverability. Attached Figure Description
[0024] Figure 1 The diagram shown is a schematic of the milling machine steering system in Example 1;
[0025] Figure 2 The diagram shown is a side view of the milling machine steering system structure in Example 1;
[0026] Figure 3 The diagram shown is a schematic diagram of the milling machine's working mode steering when the steering traction unit is in the first position in Embodiment 2.
[0027] Figure 4 The diagram shown is a schematic representation of the limiting device in Embodiment 2.
[0028] Figure 5 The diagram shown is a schematic diagram of the milling machine's working mode steering when the steering traction unit is in the second position in Embodiment 2.
[0029] Reference numerals in the attached diagram: 1. Right front steering traction, 2. Front steering tie rod, 3. Left front steering traction, 4. Right rear steering traction, 5. Right rear outrigger cantilever, 6. Left rear steering traction, 7. Right front track, 8. Left front track, 9. Right rear track, 10. Left rear track, 11. Limit bolt, 12. Limit block, 13. Right rear steering cylinder, 14. Right rear swing cylinder, 15. Left rear steering cylinder, 16. Axle, 17. Frame. Detailed Implementation
[0030] The present invention will be further described below with reference to specific embodiments.
[0031] Example 1:
[0032] 1. For example Figure 1 , Figure 2 As shown, this embodiment introduces a milling machine steering system, including steering traction units respectively provided on the left front side, right front side, left rear side and right rear side of the frame 17. The steering traction units are respectively connected to the walking track units. A front connecting member is provided between the two steering traction units on the front side. At least one steering traction unit on the rear side is connected to a rear connecting member. At least one walking track unit on the rear side is connected to a limit device. A drive device is provided between the steering traction unit and the walking track unit.
[0033] The rear connecting part is linked to the corresponding steering traction unit to switch between the first position and the second position. When the steering traction unit is in the first position, the right front traveling track 7 and the left front traveling track 8 corresponding to the right front steering traction unit 1 and the left front steering traction unit 3 rotate. When the steering traction unit is in the second position, all four traveling tracks corresponding to the steering traction unit rotate.
[0034] The front connecting part is the front steering tie rod 2, which is connected between the right front steering traction unit 1 and the left front steering traction unit 3. The front steering tie rod 2 controls the right front steering traction unit 4, the left front steering traction unit 3, the right front track 7 and the left front track 8 through the hydraulic cylinder.
[0035] The rear connecting part is the right rear outrigger cantilever 5, which is connected to the right rear steering traction unit 4. The swing of the right rear outrigger cantilever 5 controls the steering of the right rear walking track 9.
[0036] The swing of the right rear outrigger cantilever 5 and the coupled motion of the right rear walking track 9 can realize the swinging in and out of the right rear outrigger cantilever 5 during the movement of the milling machine.
[0037] The first position is with the right rear outrigger cantilever 5 swinging out, driving the right rear steering traction unit 4 to be located on the outside, and the right front traveling track 7, left front traveling track 8 and left rear traveling track 10 turning.
[0038] The second position is with the right rear outrigger cantilever 5 swinging in, driving the right rear steering traction unit 4 to be located on the inside, and the right front traveling track 7, left front traveling track 8, right rear traveling track 9 and left rear traveling track 10 coordinating the steering.
[0039] The limiting device is installed on the right rear travel track 9 and the left rear travel track 10. The limiting device includes a limiting bolt 11 and a limiting block 12. The limiting block 12 is installed on one side of the left rear travel track 10. A set of limiting bolts 11 is provided on both sides below the limiting block 12. The limiting bolts 11 are installed at both ends of the left rear steering traction unit 6.
[0040] The drive unit includes a right rear steering cylinder 13, a right rear swing cylinder 14 and a left rear steering cylinder 15. The right rear steering cylinder 13 is connected to the right rear steering traction unit 4. The right rear track 9 drives the left rear track 10 to turn through the right rear swing cylinder 14. The left rear steering cylinder 15 is connected to the left rear steering traction unit 6.
[0041] The left rear steering cylinder 15 pushes the left rear steering traction unit 6 to drive the left rear travel track 10 to rotate. The steering angle is ±10°. When the left rear travel track 10 reaches the turning angle limit, the limit bolt 11 contacts the limit block 12.
[0042] The right rear outrigger arm 5 has a pivot 16 at one end, and the right rear outrigger arm 5 is hinged to the frame 17 through the pivot 16.
[0043] Specifically, the steering traction unit includes a right front steering traction unit 1, a left front steering traction unit 3, a right rear steering traction unit 4, and a left rear steering traction unit 6; the track unit includes a right front track 7, a left front track 8, a right rear track 9, and a left rear track 10; the steering traction unit is connected to the track unit in a one-to-one correspondence to control the track unit to turn.
[0044] Specifically, the front steering tie rod 2 connects the right front steering traction unit 1 and the left front steering traction unit 3, realizing the steering angle difference between the left front travel track 8 and the right front travel track 7, reducing the turning radius, and ensuring that the whole machine achieves the smallest possible turning radius. The drive unit is connected to the steering traction unit and is used to control the steering system for travel and steering operations. The right rear outrigger cantilever 5 is connected to the right rear steering traction unit 4, and the right rear outrigger cantilever 5 is controlled by a hydraulic cylinder to swing, driving the right rear travel track 9 to the first position and the second position for swinging in and out operations. When the right rear travel track 9 is in the first position, the right front travel track 7, the left front travel track 8, and the left rear travel track 10 turn. When the right rear travel track 9 is in the second position, the right front travel track 7, the left front travel track 8, the right rear travel track 9, and the left rear travel track 10 turn in coordination. Both the right rear track 9 and the left rear track 10 are equipped with limit bolts 11 and limit blocks 12. When the turning angle limit of ±10° is reached, the limit bolts 11 and limit blocks 12 will contact each other to avoid the risk of interference between the track and other components.
[0045] Example 2:
[0046] This embodiment describes a milling machine steering system, the specific implementation of which is as follows:
[0047] like Figure 3 As shown, with the right rear outrigger cantilever 5 extended and the right rear track 9 in its first position, the vehicle's steering mode primarily relies on the deflection of the left front track 8 and the right front track 7 to achieve steering movement. The drive unit propels the right front steering traction unit 1, causing the right front track 7 to rotate. Simultaneously, the right front steering traction unit 1, via the front steering tie rod 2, pushes the left front steering traction unit 3, causing the left front track 8 to rotate. In this steering mode, the right rear track 7 and the left rear track 8 do not have steering functionality. The instantaneous center of the vehicle's steering speed is near the axis of the left rear track 8 and the right rear track 7, ensuring that all four tracks roll purely during steering, reducing track wear and extending service life.
[0048] like Figure 4 As shown, when the drive unit pushes the left rear steering traction unit 6 to rotate the left rear walking track 10, the steering angle is ±10°. When the left rear walking track 10 reaches the turning angle limit, the limit bolt 11 will contact the limit block 12, thereby avoiding the risk of interference between the left rear walking track 10 and other components.
[0049] like Figure 5As shown, the right rear outrigger cantilever 5 is in the second position with the right rear track 9 in the middle. All four tracks of the vehicle can now steer. The right front steering traction unit 1, driven by the drive unit, rotates the right front track 7 and the left front track 8. The right rear steering traction unit 4, controlled by the drive unit, rotates the right rear track 9 to achieve a steering angle of ±10°. Simultaneously, the left rear steering traction unit 6, controlled by the drive unit, rotates the left rear track 10 to achieve a steering angle of ±10°. This coordinated steering of the four tracks, even when the right front track 7 has a small turning angle, utilizes the coordinated rotation of the right rear track 9 and the left rear track 10 to shift the instantaneous center of rotation of the entire vehicle forward. This results in a smaller turning radius, improved vehicle maneuverability in narrow passages, and enhanced equipment controllability.
[0050] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A milling machine steering system, characterized in that, The vehicle frame (17) includes steering traction units respectively provided on the left front side, right front side, left rear side and right rear side, and each steering traction unit is connected to a walking track unit. A front connecting piece is provided between the two steering traction units on the front side, and at least one steering traction unit on the rear side is connected to a rear connecting piece. At least one walking track unit on the rear side is connected to a limit device, and a drive device is provided between the steering traction unit and the walking track unit. The rear connector is linked to the corresponding steering traction unit to switch between the first position and the second position. When the steering traction unit is in the first position, the drive device drives the right front walking track (7) and the left front walking track (8) corresponding to the right front steering traction unit (1) and the left front steering traction unit (3) to rotate. When the steering traction unit is in the second position, the drive device drives all four walking tracks corresponding to the steering traction unit to rotate.
2. The milling machine steering system according to claim 1, characterized in that, The front connecting part is a front steering tie rod (2), which is connected between the right front steering traction unit (1) and the left front steering traction unit (3). The front steering tie rod (2) controls the right front steering traction unit (4), the left front steering traction unit (3), the right front track (7) and the left front track (8) through a hydraulic cylinder.
3. The milling machine steering system according to claim 1, characterized in that, The rear connecting member is the right rear outrigger cantilever (5), which is connected to the right rear steering traction (4). The swing of the right rear outrigger cantilever (5) controls the steering of the right rear walking track (9).
4. The milling machine steering system according to claim 1, characterized in that, The swing of the right rear outrigger cantilever (5) and the coupled motion of the right rear walking track (9) enable the right rear outrigger cantilever (5) to swing in and out during the milling machine's movement.
5. The milling machine steering system according to claim 1, characterized in that, The first position is when the right rear outrigger cantilever (5) swings out, driving the right rear steering traction unit (4) to be located on the outside, and the right front walking track (7), left front walking track (8) and left rear walking track (10) turn.
6. The milling machine steering system according to claim 1, characterized in that, The second position is when the right rear outrigger cantilever (5) is swung in, driving the right rear steering traction unit (4) to be located on the inside, and the right front walking track (7), left front walking track (8), right rear walking track (9) and left rear walking track (10) steer in coordination.
7. The milling machine steering system according to claim 1, characterized in that, The limiting device is installed on the left rear walking track (10), wherein the limiting device includes a limiting bolt (11) and a limiting block (12). The limiting block (12) is installed on one side of the left rear walking track (10), and a set of limiting bolts (11) is provided on both sides below the limiting block (12). The limiting bolts (11) are installed at both ends of the left rear steering traction unit (6).
8. The milling machine steering system according to claim 1, characterized in that, The drive unit includes a right rear steering cylinder (13), a right rear swing cylinder (14), and a left rear steering cylinder (15). The right rear steering cylinder (13) is connected to the right rear steering traction (4) unit. The right rear track (9) drives the left rear track (10) to turn through the right rear swing cylinder (14). The left rear steering cylinder (15) is connected to the left rear steering traction unit (6).
9. The milling machine steering system according to claim 1, characterized in that, The left rear steering cylinder (15) pushes the left rear steering traction unit (6) to drive the left rear walking track (10) to rotate. The steering angle is ±10°. When the left rear walking track (10) reaches the turning angle limit, the limiting bolt (11) contacts the limiting block (12).
10. The milling machine steering system according to claim 1, characterized in that, The right rear outrigger cantilever (5) has a pivot (16) at one end, and the right rear outrigger cantilever (5) is hinged to the frame (17) through the pivot (16).