Side-mounted passive follow-up steering suction nozzle wheel assembly for sweeper truck

Abstract

The invention relates to a side-mounted passive follow-up steering suction nozzle wheel assembly for a sweeper truck. The side-mounted passive follow-up steering suction nozzle wheel assembly comprises a mounting bracket, two ball head assemblies, a bearing seat, a shaft, a tire assembly and the like. The two ball head assemblies are connected with the installation support through the tapered ball rods of the ball head assemblies, the ball seats with the flanges of the ball head assemblies are connected with the bearing seat, and therefore the double-ball-head parallel suspension is formed, a virtual master pin is formed, the connecting line of the two ball rod installation holes is arranged to form an included angle with the perpendicular line, and the adjusting shim is additionally arranged on the lower ball head assembly. Kingpin backward inclination and kingpin inward inclination are achieved respectively, and the tire assembly is endowed with the functions of passive follow-up steering, automatic aligning and linear stable walking. Particularly, through the structural design, the central plane of the tire coincides with the axis of the virtual main pin, zero transverse offset distance is achieved, and the eccentric wear phenomenon of the side-mounted steering wheel is eliminated fundamentally. In addition, the tire assembly adopts a multi-stage sealing and special bearing structure, so that the durability and the safety under severe working conditions are improved.

Description

Technical Field

[0001] This invention relates to the field of road sweeper technology, specifically to a side-mounted passive follow-up steering suction nozzle wheel assembly for road sweepers. Background Technology

[0002] Sweeper trucks are the main equipment for mechanized road cleaning. Their suction nozzles are typically equipped with multiple suction wheel assemblies to support the nozzle and maintain a proper gap between it and the ground, allowing the nozzle to float and ensuring uniform suction. The suction nozzle itself is generally positioned between the front and rear axles, but can also be positioned in front of the front axle or behind the rear axle. Overall, it is passively towed and does not have forward or steering capabilities. Most existing sweeper trucks use side-mounted directional wheels that lack steering functionality.

[0003] During operation, the sweeper truck needs to adjust its route to avoid curves or obstacles. Since vehicles cannot travel in a perfectly straight line, the suction nozzle passively follows the vehicle's curves. Because the directional wheels cannot steer, they can only adapt to changes in trajectory through lateral tire sliding. This increases the lateral load on the tires, transforming the single rolling friction motion into a combination of rolling and sliding friction. This easily leads to rapid tire wear and a significantly shortened lifespan, typically lasting only about six months. This not only increases maintenance costs and frequency but also affects the sweeper truck's operational continuity and economy.

[0004] While a small number of suction nozzle wheels with steering capabilities exist on the market, most suffer from complex structures, large sizes, or difficulty in adapting to the wide range of side-mounted interfaces on existing road sweepers. In particular, for side-mounted steering wheels, effectively addressing the inherent problem of uneven tire wear and achieving a compact, reliable, maintenance-free product that can directly replace existing directional wheels remains a critical technological gap that urgently needs to be filled. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a side-mounted passive follow-up steering suction nozzle wheel assembly for road sweepers, filling a market gap. Secondly, it aims to completely solve the problems of uneven wear and non-compact structure in side-mounted suction nozzle wheel assemblies. Furthermore, it solves the problem of rapid wear of existing directional wheels, significantly extending tire life and enabling the vehicle suction nozzle body to operate without maintenance or height adjustment throughout the suction nozzle wheel assembly's lifespan, allowing the road sweeper to maintain its optimal operating condition for an extended period.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper, comprising:

[0007] Mounting bracket for side mounting on the nozzle body;

[0008] Two ball head assemblies, each ball head assembly including a ball seat with a two-hole flange face and a tapered ball shaft, wherein the ball head at the end of the ball shaft away from the tapered end is fitted into the ball head hole of the ball seat;

[0009] The ball joints of the two ball joint assemblies pass through the two ball joint mounting holes on the mounting bracket and are locked with nuts so that the conical surface of the ball joint mates with the conical surface of the mounting hole.

[0010] The bearing housing is connected to the ball seat flanges of the two ball head assemblies by a first bolt;

[0011] The integral bearing is an integral maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing, and is installed in the bearing housing, while axial positioning is achieved by an oil seal seat;

[0012] A shaft passes through the inner ring of the integral bearing;

[0013] The tire assembly includes a hub assembly and a tire that are either integrally vulcanized or assembled separately; the hub assembly is assembled to the front end of the axle via a tapered surface fit and is locked by a front end cap assembly; at the same time, the rear end of the axle is locked to the inner ring of an integral bearing via a rear end cap assembly.

[0014] The line connecting the centers of the two ball joint assemblies forms a virtual kingpin, and the center plane of the tire assembly coincides with the axis of the virtual kingpin to achieve zero lateral offset.

[0015] Preferably, the line connecting the centers of the two ball joint mounting holes on the mounting bracket forms an angle B with the vertical line, thereby achieving a backward tilt of the kingpin. The axial height of the shim between the ball seat flange and the bearing seat is adjusted by increasing or decreasing the axial height of the shim to finely adjust the length difference between the two ball joint assemblies, thereby achieving a slight inward tilt of the kingpin.

[0016] Preferably, the maintenance-free double-row angular contact ball bearing and the maintenance-free double-row tapered roller bearing are provided with a first skeleton oil seal on both the outer and inner sides, and also include a bearing outer ring, symmetrically arranged double-half bearing inner rings, and two ball assemblies located between the bearing inner ring and the bearing outer ring. At the same time, the minimum diameter D1 of the bearing outer ring is smaller than the maximum diameter D2 of the bearing inner ring.

[0017] Preferably, the oil seal seat is connected to the bearing seat by a second bolt. Both the inside of the oil seal seat and the tail of the bearing seat are provided with oil seal positions. Each oil seal position is equipped with a second skeleton oil seal. At the same time, a first O-ring (23) is provided between the oil seal seat (5) and the bearing seat (4). A second O-ring (11) is also provided between the hub assembly (2) and the oil seal seat (5), forming a multi-stage sealing structure.

[0018] Preferably, the spokes of the hub assembly are provided with at least two disassembly auxiliary threaded holes.

[0019] Preferably, a dust cover is provided between the ball seat and the cue of the ball head assembly. The two ends of the dust cover are connected to the ball seat and the cue respectively by clamps. The dust cover is pre-filled with an appropriate amount of long-lasting grease, so that the ball head assembly has maintenance-free capability. At the same time, the ball head at one end of the cue is assembled into the ball head hole of the ball seat by riveting.

[0020] Preferably, the front end cap assembly includes a front end cap located at the front end of the shaft and a first cap bolt for pressing the front end cap, and a decorative cover is mounted on the front end cap; the rear end cap assembly includes a rear end cap located at the rear end of the shaft and positioned by a locating pin, and a second bolt, a spring washer, and a stop washer assembled in sequence.

[0021] Preferably, the included angle B is in the range of 0.5°-35°.

[0022] As a preferred embodiment, the bearing housing, integral bearing, shaft, front cover of the front cover assembly, rear cover of the rear cover assembly, oil seal seat, and second skeleton oil seal are assembled to form a special type of integral hub bearing with enhanced sealing performance.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. This invention innovatively employs a double-ball joint parallel suspension. Through a simple combination of several parts such as mounting brackets, bearing seats, and adjusting shims, it simultaneously undertakes the functions of upper and lower wheel limit, left and right limit, steering amplitude limit, circumferential limit of the bearing seat, and maintenance-free steering structure. This achieves the functional goals of support, passive follow-up steering, automatic return to center, stable straight-line travel, steering amplitude control, and maintenance-free operation. Because the ball joint heads are positioned away from the bracket and close to the wheel spokes, and the line connecting the centers of the two ball joint assemblies forms a virtual kingpin, with the center plane of the tire assembly coinciding with the axis of the virtual kingpin, zero lateral offset can be achieved even with side-mounted design. This completely solves the problem of uneven tire wear that easily occurs in side-mounted passive follow-up steering wheels, significantly reducing tire wear and extending tire life by tens of times compared to traditional directional wheels.

[0025] 2. This invention solves the problem that the wear rate of the existing directional front wheel tires is much higher than that of the directional rear wheel tires, which leads to the suction nozzle tilting forward and backward and uneven air intake around the circumference. It also enables customers' products to maintain the height of the suction nozzle body without adjustment or maintenance during the life cycle of the suction nozzle wheel, ensuring that the customer's products can maintain the factory condition for a long time after leaving the factory and stabilize the overall cleaning rate of the vehicle.

[0026] 3. The structural characteristics of the double ball joint parallel suspension of this invention integrate support, steering, return, and limit functions into one, and its space occupied in the tire axial direction is extremely small, which enables the low-profile and compact side-mounted design of the entire suction wheel assembly.

[0027] 4. Compared with the existing top-mounted passive follow-up steering wheel, the side-mounted passive follow-up walking wheel of the present invention can reduce its installation height by at least 50% and does not significantly increase its width laterally. It can be interchanged with existing vehicles through a simple transition bracket, thus solving the technical obstacles to improving product quality in the existing market.

[0028] 5. This invention, through the coordinated design of kingpin tilt and inclination, ensures high stability of the suction wheel assembly during straight-line driving and automatic self-centering capability after turning, significantly reducing the problem of high-frequency head swaying during driving.

[0029] 6. Compared with the unique first skeleton oil seal design and special anti-detachment design of the bearing outer ring, the integral maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing adopted in this invention further improves the sealing effect in harsh environments. In the case of untimely maintenance by customers, it reduces the loss of parts that are not intentionally abandoned by customers, reduces the risk of parts being lost, and thus reduces the probability of traffic accidents caused by end users leaving parts on the road, thereby improving the safety of road operations.

[0030] 7. The bearing housing, integral bearing, shaft, front end cap, rear end cap, oil seal seat, and second skeleton oil seal of this invention are assembled into a special type of integral hub bearing with enhanced sealing performance. Furthermore, the multi-layered sealing on both the inner and outer sides of the bearing allows it to fully withstand the extremely harsh environmental conditions near the suction nozzle of the sweeper truck, improving its environmental adaptability. The addition of a second O-ring not only significantly reduces the movement clearance between the wheel spokes and the bearing housing but also achieves a height difference between the wheel spokes and the outer surface of the bushing, ensuring that most dust is blocked outside the O-ring and falls off as the wheel rotates. With these sealing measures, compared to similar products, the bearing's safe operating time increases exponentially.

[0031] 8. The single bolt locking connection between the wheel hub assembly and the shaft on the conical surface of the present invention and the threaded holes on the wheel spokes make installation and after-sales disassembly and maintenance more convenient. Attached Figure Description

[0032] Figure 1 This is the front view of the present invention;

[0033] Figure 2 This is the right view of the present invention;

[0034] Figure 3 yes Figure 2 Cross-sectional view along section line AA;

[0035] Figure 4 This is a three-dimensional structural diagram of the connection between the ball joint assembly, the mounting bracket, and the bearing seat in this invention;

[0036] Figure 5 This is a schematic diagram showing that the ball joint assembly, mounting bracket, and bearing housing are not connected in this invention;

[0037] Figure 6 This is a cross-sectional schematic diagram of the connecting part of the ball joint assembly of the present invention;

[0038] Figure 7 This is a top view of the ball joint assembly of the present invention;

[0039] Figure 8 This is a schematic diagram of achieving zero offset between the virtual kingpin and the tire centerline in this invention (where 8a represents a schematic diagram of the virtual kingpin and the tire centerline coinciding and adjusting, and 8b represents a schematic diagram of the line connecting the centers of the two ball joints).

[0040] Figure 9 This is a schematic diagram of the vehicle's straight-line driving and turning direction according to the present invention (where 9a is a schematic diagram of the vehicle's original straight-line state, and 9b is a schematic diagram of the vehicle starting to turn).

[0041] Figure 10 This is a schematic diagram of the passive following and automatic steering of the present invention (where 10a is a schematic diagram of the wheel passively following the steering state, and 10b is a schematic diagram of the state after the steering function is realized).

[0042] Figure 11 This is a schematic diagram of tire steering sway suppression in this invention;

[0043] Figure 12 This is a schematic diagram of the structure of the maintenance-free double-row angular contact ball bearing or the maintenance-free double-row tapered roller bearing in this invention;

[0044] Figure 13 yes Figure 8 Enlarged schematic diagram of point I in 8b;

[0045] Figure 14 yes Figure 8 Enlarged schematic diagram of point II in 8b. Detailed Implementation

[0046] The following will combine Figure 1-14 The present invention will be described in detail below. The illustrative embodiments and descriptions herein are used to explain the invention, but are not intended to limit the invention.

[0047] A side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper, such as Figure 3 As shown, it includes:

[0048] Mounting bracket 14 is used for side mounting on the nozzle body;

[0049] Two ball head assemblies 3, each ball head assembly 3 includes a ball seat 35 and a tapered ball rod 34. The ball seat 35 is configured as a flange structure with two bolt mounting holes, and a ball head hole is provided in the middle of the ball seat. The ball head 31 of the ball rod 34 at the tapered end II is fitted into the ball head hole of the ball seat 35.

[0050] Among them, the ball rods 34 of the two ball head assemblies 3 pass through the two ball rod mounting holes 33 on the mounting bracket 14 respectively, and are locked by nuts 15, so that the conical surface of the ball rod 34 matches the conical surface of the mounting hole, thereby realizing a stable connection between the ball head assembly 3 and the mounting bracket 14.

[0051] The bearing housing 4 is connected to the ball seat flanges of the two ball head assemblies 3 by the first bolt 22. Each ball head assembly 3 and the bearing housing 4 are locked together by two bolts screwed into the bolt mounting holes.

[0052] The integral bearing 10 is an integral maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing installed in the bearing housing 4. Axial positioning is achieved through an oil seal seat 5, which is connected to the bearing housing 4 by four second bolts 13. Oil seal positions are provided inside the oil seal seat 5 and at the tail of the bearing housing 4. A second skeleton oil seal 12 is installed in each oil seal position. This second skeleton oil seal can be replaced by a maintenance-free stainless steel PTFE multi-lip oil seal. A first O-ring 23 is provided between the oil seal seat 5 and the bearing housing 4. In this solution, the maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing can eliminate the traditional inner and outer rings of the bearing. The original bearing housing, original shaft, etc., can be made into an integral bearing with a mounting flange and mounting shaft. This solution improves quality and reduces costs.

[0053] Shaft 7 passes through the inner ring of the integral bearing 10;

[0054] The tire assembly consists of a hub assembly 2 and a tire 1, which are integrally formed by vulcanization or assembled separately from the hub assembly 2 and the tire 1. The hub assembly 2 is fitted to the front end of the shaft 7 through a tapered surface fit to achieve a tapered surface connection and locking between the two, and is further secured by a front end cap assembly. At the same time, the rear end of the shaft is further secured to the inner ring of the integral bearing 10 through a rear end cap assembly. The hub assembly 2 is provided with a mounting groove for installing a second O-ring 11. After installation, the second O-ring 11 on the hub assembly 2 makes slight contact with the oil seal seat 5 to achieve a simple seal, thereby reducing the intrusion of water and dust into the space between the hub assembly 2 and the second skeleton oil seal 12.

[0055] The line connecting the centers of the two ball joint assemblies 3 forms a virtual kingpin, and the center plane of the tire assembly coincides with the axis of the virtual kingpin to achieve zero lateral offset.

[0056] Specifically, the front end cap assembly includes a front end cap 6 located at the front end of the shaft 7 and a first cap bolt 8 for pressing the front end cap 6. A decorative cover 9 is mounted on the front end cap 6. The rear end cap assembly includes a rear end cap 16 located at the rear end of the shaft and positioned by a locating pin 17, as well as a second bolt 18, a spring washer 19, and a stop washer 20 assembled in sequence. This assembly achieves the locking of the shaft 7 and the inner ring 27 of the bearing without loosening.

[0057] The bearing housing, integral bearing, shaft, front end cap, rear end cap, oil seal seat, and second skeleton oil seal of this invention are assembled into a special type of integral hub bearing with enhanced sealing performance, which improves sealing performance and extends service life.

[0058] like Figure 4 As shown, the core steering component of this side-mounted passive follow-up steering nozzle wheel assembly consists of two ball joint assemblies 3, a mounting bracket 14, and a bearing seat 4, along with four first bolts 22 and two nuts 15. Several adjusting shims 24 are provided between the ball seat 35 and the bearing seat 4, and they are assembled into a single unit according to the orientation shown in the diagram. Figure 6 The ball head assembly 3 shown is designed with a ball seat with a flange structure containing two holes (two bolt mounting holes), and a ball shaft with a tapered shape and threads. The ball seat 35 is designed with a flange shape containing two holes, primarily to eliminate manufacturing errors in the two tapered holes on the mounting bracket 14 (connecting to the tapered holes on the ball shaft) and the two sets of ball seat mounting threaded holes on the bearing housing (the clearance between the ball head and the ball seat is extremely small, making it impossible to eliminate manufacturing errors in the hole positions). After the ball head 31 at one end of the ball shaft 34 is assembled into the ball head hole of the ball seat using a special riveting process, a dust cover 30 is installed between the ball seat and the ball shaft. The dust cover 30 is connected to the ball seat 35 and the ball shaft 34 respectively by clamps at both ends. The dust cover is pre-filled with an appropriate amount of long-lasting grease, allowing the ball head assembly 3 to have three degrees of freedom: back-and-forth swing, left-and-right swing, and rotation around its axis. This provides maintenance-free operation and waterproof / dustproof capabilities. When the ball head assembly 3 is not fixed to the mounting bracket 14 and the bearing housing 4, the degrees of freedom of the ball head itself are as follows... Figure 7 As shown.

[0059] Will Figure 5 All parts are arranged according to Figure 4 After connection, the two ball joint assemblies, which originally each had three degrees of freedom, become single-degree-of-freedom assemblies, and can only revolve around the virtual kingpin a2 formed by the line connecting the centers of the two ball joints (see reference). Figure 5 The ball head swings within a set angle range (the swing angle is determined by the ball head structure; therefore, the ball head also has a specific amplitude limiting function). The line connecting the centers of the two club mounting holes 33 on the mounting bracket 14 is set to form a certain angle B with the vertical line (refer to...). Figure 5This creates a kingpin tilt effect, and the axial height of the adjusting shim 24 between the ball joint assembly 3 and the bearing housing 4 is adjusted by increasing or decreasing the axial height of the shim 24 to finely adjust the length difference between the two ball joint assemblies 3, achieving a slight inward tilt of the kingpin. Through the special design and placement of the two ball joint assemblies, a certain angle of steering function is achieved, as well as the kingpin tilt and inward tilt that maintain the straight-line movement of the wheel, while also achieving a maintenance-free function for the entire steering structure. While undertaking the steering function, the ball joint assembly 3 also serves as the connecting component between the mounting bracket and the bearing housing, bearing alternating loads from the wheel in the vertical up-down, front-back, and left-right directions along the ball joint axis.

[0060] pass Figure 8 It can be clearly seen that the virtual kingpin a2, formed by the centers O3 and O4 of the two ball joints, forms an angle B with the vertical line a1. (Angle B is controlled within the range of 0.5° to 35°, with the specific value matched according to the wheel diameter, load, and speed). The extension line of the virtual kingpin intersects the ground at point O2, and the vertical line a1 intersects the ground at point O1. A self-aligning arm L1 is formed between O1 and O2. Through the special design of the double ball joint parallel suspension, the tire centerline a1 (i.e., the tire center plane) is kept coincident with the virtual kingpin O3-O4 (i.e., the axis of a2), achieving a zero offset (tire wear radius is 0) effect and completely solving the tire wear phenomenon that is easily caused by side steering.

[0061] like Figure 9 As shown, when the wheel travels normally along the Y-axis (refer to schematic diagram 9a), its traction force F coincides with the Y-axis. When the vehicle begins to turn at a certain angle D, a traction force F is generated on the wheel through force transmission, forming a certain angle with the original travel direction Y. F will generate a component force F1 along the Y direction and a component force F2 along the axis of the ball joint. F1 is directed towards the front of the wheel and is responsible for pulling the wheel forward. F2 pushes the wheel towards the turning side of the vehicle. Since the wheel is in contact with the ground, the ground will generate a reverse force F3 acting on the tire at point O1. Under the influence of the return arm L1, F3 generates a counterclockwise turning torque around the intersection point O2 of the virtual kingpin and the ground, causing the wheel to turn.

[0062] like Figure 10 As shown, the wheels turn under the influence of the steering torque. The traction force F coincides with the Y-axis again when the direction of travel of the support body aligns with the direction of travel of the wheels. The component force F2 disappears, the wheels complete the steering, and begin straight-line travel.

[0063] like Figure 11As shown, due to the kingpin inclination and caster configurations, when the tire turns, one side of the tire is compressed while the other side tends to be lifted. Under no load, this creates a ground clearance angle C. In actual driving conditions, because there is a load above the tire, angle C is often 0, while the rubber on the originally compressed side is severely compressed and has a strong rebound tendency. This ensures the tire's straight-line stability and automatic self-centering function, significantly reducing the problem of high-frequency left-right swaying caused by minor road surface disturbances.

[0064] Specifically, the integral maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing in this invention differs only in the rolling elements; all other structures are the same. Figure 12 As shown, a first skeleton oil seal 29 is provided on both the outer and inner sides of the bearing. It also includes a bearing outer ring 26, symmetrically arranged double half bearing inner rings 27, and two ball assemblies 28 located between the bearing inner ring and the bearing outer ring. Compared with conventional bearings of the same type on the market, this application upgrades the original seal to a skeleton seal with a secondary lip and a spring. Compared with the springless multi-lip seal structure on the market, it is more suitable for the water and dust conditions of road sweepers and improves service life. At the same time, the minimum diameter D1 of the bearing outer ring is smaller than the maximum diameter D2 of the bearing inner ring. This design ensures that even if the bearing is completely damaged, the tire assembly and axle and other parts will not completely detach from the bearing outer ring and be abandoned on the road, reducing customer maintenance losses and traffic accidents caused by detached parts on the road.

[0065] like Figure 13 , Figure 14 As shown, this component demonstrates a comprehensive improvement in the waterproof and dustproof measures for the bearings, specifically designed for the harsh operating conditions of road sweepers and washers, characterized by high dust and water content. Figure 13 As shown in the enlarged view, the second O-ring 11, the first O-ring 23, the second skeleton oil seal (12), and the bearing's own skeleton oil seal are sequentially sealed on the outer side of the bearing. (See enlarged view). Figure 14 As shown, the bearing inner cover 21, the second skeleton oil seal, and the bearing's own first skeleton oil seal 29 are used to seal, thus forming a multi-stage sealing structure.

[0066] The space formed by the two first skeleton oil seals is pre-filled with long-lasting grease, and the space formed by the two second skeleton oil seals is also pre-filled with long-lasting grease.

[0067] Secondly, such as Figure 2 As shown, the spokes of the hub assembly 2 are provided with at least two auxiliary disassembly threaded holes 25 to facilitate disassembly for after-sales maintenance.

[0068] The technical solutions provided by the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only for helping to understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the embodiments of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper, characterized in that, include: Mounting bracket (14) is used for side mounting on the nozzle body; Two ball head assemblies (3), each ball head assembly (3) includes a ball seat (35) with a two-hole flange face and a tapered ball rod (34), wherein the ball head (31) of the ball rod away from the tapered end is fitted into the ball head hole of the ball seat; Among them, the ball rods of the two ball head assemblies (3) pass through the two ball rod mounting holes (33) on the mounting bracket (14) respectively, and are locked by nuts (15) so that the conical surface of the ball rod (34) matches the conical surface of the mounting hole; The bearing housing (4) is connected to the ball seat flanges of the two ball head assemblies (3) by means of the first bolt (22); The integral bearing (10) is an integral maintenance-free double-row angular contact ball bearing or maintenance-free double-row tapered roller bearing, and is installed in the bearing housing (4), while axial positioning is achieved through the oil seal seat (5); Shaft (7) passes through the inner ring of the integral bearing (10); The tire assembly includes a hub assembly (2) that is vulcanized in one piece or assembled separately and a tire (1); the hub assembly (2) is assembled to the front end of the shaft (7) by a tapered surface fit and is locked by a front end cap assembly; at the same time, the rear end of the shaft is locked to the inner ring of the integral bearing (10) by a rear end cap assembly; The line connecting the centers of the two ball joint assemblies (3) forms a virtual kingpin, and the center plane of the tire assembly coincides with the axis of the virtual kingpin to achieve zero lateral offset.

2. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The line connecting the centers of the two ball joint mounting holes (33) on the mounting bracket (14) forms an angle B with the vertical line, thereby achieving the backward tilting of the kingpin. The length difference between the two ball joint assemblies (3) is finely adjusted by increasing or decreasing the axial height of the shim (24) between the ball seat flange and the bearing seat (4), thereby achieving the inward tilting of the kingpin.

3. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The maintenance-free double-row angular contact ball bearing and the maintenance-free double-row tapered roller bearing are provided with a first skeleton oil seal (29) on both the outer and inner sides. They also include a bearing outer ring (26), a symmetrically arranged double-half bearing inner ring (27), and two ball assemblies (28) located between the bearing inner ring and the bearing outer ring. Meanwhile, the minimum diameter D1 of the bearing outer ring is smaller than the maximum diameter D2 of the bearing inner ring.

4. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The oil seal seat is connected to the bearing seat by the second bolt (13). The oil seal seat (5) and the bearing seat (4) are both provided with oil seal positions. The oil seal positions are equipped with second skeleton oil seals (12). At the same time, the oil seal seat (5) and the bearing seat (4) are provided with a first O-ring (23). The hub assembly (2) and the oil seal seat (5) are also provided with a second O-ring (11), forming a multi-stage sealing structure.

5. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The hub assembly (2) has at least two disassembly auxiliary threaded holes (25) on its spokes.

6. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The ball head assembly (3) has a dust cover (30) between the ball seat and the cue stick. The two ends of the dust cover are connected to the ball seat and the cue stick respectively by clamps, so that the ball head assembly (3) has maintenance-free capability. At the same time, the ball head at one end of the cue stick is assembled into the ball head hole of the ball seat by riveting.

7. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 1, characterized in that: The front end cap assembly includes a front end cap (6) located at the front end of the shaft (7) and a first cap bolt (8) for pressing the front end cap (6). A decorative cover (9) is mounted on the front end cap (6). The rear end cap assembly includes a rear end cap (16) located at the rear end of the shaft by a positioning pin (17), and a second bolt (18), a spring washer (19), and a stop washer (20) assembled in sequence.

8. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 2, characterized in that: The included angle B ranges from 0.5° to 35°.

9. The side-mounted passive follow-up steering suction nozzle wheel assembly for a road sweeper according to claim 4, characterized in that: The bearing housing, integral bearing, shaft, front cover of the front cover assembly, rear cover of the rear cover assembly, oil seal seat, and second skeleton oil seal are assembled to form an integral wheel hub bearing.

Images