A steering system for a forklift truck

Abstract

The utility model discloses a kind of steering systems for fork truck, including steering control mechanism, connecting support, the steering control mechanism with the connecting support upper end connection, the connecting support lower end is connected with steering sensor by slewing support bearing, the support slewing bearing outside is connected with the mounting base for supporting the support slewing bearing, the steering sensor is variable resistance sensor, the vehicle speed of the fork truck is associated with the steering hand control force of driver to steering system by setting the steering sensor of variable resistance, the steering control force size of vehicle changes with vehicle operating speed change and is realized.

Description

Technical Field

[0001] This utility model relates to the technical field of forklift steering systems, specifically a steering system for forklifts. Background Technology

[0002] The steering system is a crucial component of forklifts. As industrial vehicles, most forklifts currently rely on hydraulic steering, which uses a gear pump to drive hydraulic oil as the medium. When the steering wheel or handle is turned left or right, a mechanical structure switches the left and right hydraulic circuits of the steering gear, thus enabling the forklift to turn left or right. While this steering control method meets the forklift's steering requirements, its constant steering force leads to discomfort due to the large amount of manual force required by the driver when the forklift is stationary. Furthermore, at high speeds, the driver's manual steering force is insufficient, and unintentional rapid turns of the steering wheel or handle can cause a rollover hazard. Utility Model Content

[0003] The purpose of this invention is to provide a steering system for forklifts to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution:

[0005] A steering system for a forklift includes a steering control mechanism and a connecting support. The steering control mechanism is connected to the upper end of the connecting support, and a steering sensor is connected to the lower end of the connecting support via a slewing bearing. A mounting base for supporting the slewing bearing is connected to the outside of the slewing bearing, and the steering sensor is a variable damping sensor.

[0006] As a further embodiment of this utility model: the steering control mechanism includes a steering support fixedly connected to the upper end of the connecting support, a connecting rod rotatably connected to the steering support, a steering rudder fixedly connected to the end of the connecting rod away from the steering support, and the rotation axis of the connecting rod on the steering support is arranged perpendicular to the axis of the connecting support.

[0007] As a further embodiment of this utility model: a gas spring for resetting the connecting rod is provided between the connecting rod and the steering support.

[0008] As a further embodiment of this utility model: the connecting support includes a support body, the support body is a cylindrical structure with an open upper end, the support body is provided with a first connecting hole for fixed connection with the steering support, and the lower end of the support body is provided with a second connecting hole for fixed connection with the slewing support bearing.

[0009] As a further embodiment of this utility model: the slewing support bearing includes an inner bearing ring and an outer bearing ring that are rotatably connected. Both the inner and outer bearing rings are provided with bearing connection holes. The mounting base includes a mounting plate, which is provided with a third connection hole and a fourth connection hole. The mounting base is fixedly connected to the bearing connection hole on the outer bearing ring through the fourth connection hole.

[0010] As a further embodiment of this utility model: the mounting base includes a mounting plate, the mounting plate is provided with a limiting block mounting groove, a limiting block is fixedly connected in the limiting block mounting groove, the limiting block is located on the outside of the connecting support, and the outer wall of the connecting support is provided with a limiting stop block that cooperates with the limiting block.

[0011] As a further embodiment of this invention: the steering sensor includes a housing and a rotor and a coil disposed within the housing, a magnetofluid is disposed between the coil and the rotor, and a Hall sensor and a magnet are disposed at the end of the rotor.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: This application sets up a variable damping steering sensor to link the forklift speed with the driver's steering force on the steering system, so that the magnitude of the vehicle's steering force changes with the vehicle's operating speed. That is, the faster the vehicle speed, the greater the steering damping, and the greater the force required to overcome the damping of the steering sensor to achieve steering, thereby greatly avoiding the risk of forklift rollover caused by rapid steering at high speeds. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the steering system structure in this embodiment;

[0014] Figure 2 This is a cross-sectional view of the steering system in this embodiment;

[0015] Figure 3 , Figure 4 This is a schematic diagram of the connecting support structure in this embodiment;

[0016] Figure 5 This is a schematic diagram of the slewing bearing structure in this embodiment;

[0017] Figure 6 This is a structural view of the limiting block in this embodiment;

[0018] Figure 7 This is a schematic diagram of the mounting base structure in this embodiment;

[0019] Figure 8 , Figure 9 This is a schematic diagram of the steering sensor structure in this embodiment;

[0020] Figure 10This is a schematic diagram of the steering system process in this embodiment;

[0021] Figure 11 This is a schematic diagram showing the output current corresponding to the vehicle speed in this embodiment;

[0022] Figure 12 This is a schematic diagram showing the output torque corresponding to the output current in this embodiment;

[0023] In the diagram: 1-Steering control mechanism, 11-Steering handle, 12-Linkage, 13-Gas spring, 14-Steering support, 2-Connecting support, 21-Support body, 22-First connecting hole, 23-Second connecting hole, 24-Limit stop, 3-Slewing support bearing, 31-Bearing outer ring, 32-Bearing inner ring, 33-Bearing connecting hole, 4-Limit block, 5-Mounting base, 51-Mounting plate, 52-Third connecting hole, 53-Limit block mounting slot, 54-Fourth connecting hole, 6-Steering sensor, 61-Housing, 62-Coil, 63-Rotor, 64-Hall sensor, 65-Magnet, 66-Magnetic fluid. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Please see Figure 1 In this embodiment of the present invention, a steering system for a forklift includes a steering control mechanism 1, a connecting support 2, a slewing support bearing 3, a limit block 4, a mounting base 5, and a steering sensor 6.

[0026] Please see Figure 2 The steering control mechanism 1 is connected to the upper end of the connecting support 2. The steering control mechanism 1 includes a steering support 14 fixedly connected to the upper end of the connecting support 2. A connecting rod 12 is rotatably connected to the steering support 14. A steering rudder 11 is fixedly connected to the end of the connecting rod 12 away from the steering support 14. The rotation axis of the connecting rod 12 on the steering support 14 is arranged perpendicular to the axis of the connecting support 2. A gas spring 13 for resetting the connecting rod 12 is provided between the connecting rod 12 and the steering support 14.

[0027] Please see Figure 3 , Figure 4The connecting support 2 includes a support body 21, which is a cylindrical structure with an open top. The support body 21 has a first connecting hole 22 that is fixedly connected to the steering support 14, and a second connecting hole 23 that is fixedly connected to the slewing bearing at the lower end. A limit stop 24 is provided on the outer wall of the support body 21.

[0028] Please see Figure 5 , Figure 6 , Figure 7 The lower end of the connecting support 2 is connected to a steering sensor 6 via a slewing bearing 3. A mounting base 5 for supporting the slewing bearing 3 is connected to the outside of the slewing bearing 3. The slewing bearing 3 includes an inner bearing ring 31 and an outer bearing ring 32 that are rotatably connected. Both the inner bearing ring 31 and the outer bearing ring 32 are provided with bearing connection holes 33. The mounting base 5 includes a mounting plate 51, which is provided with a third connection hole 52 and a fourth connection hole 54. The mounting plate 51 is fixedly connected to the vehicle frame through the third connection hole 52. The mounting base 5 is fixedly connected to the bearing connection hole 33 on the outer bearing ring 32 through the fourth connection hole 54. The mounting base 5 includes a mounting plate 51, which is provided with a limit block mounting groove 53. A limit block 4 is fixedly connected in the limit block mounting groove 53. The limit block 4 is located on the outside of the connecting support 2 and cooperates with the limit stop 24 on the outer wall of the connecting support 2, thereby limiting the rotation of the connecting support 2 from the outside and preventing excessive rotation.

[0029] Please see Figure 8 , Figure 9 The steering sensor 6 is a variable damping sensor, comprising a housing 61 and a rotor 63 and a coil 62 disposed within the housing 61. A magnetorheological fluid 66 is disposed between the coil 62 and the rotor 63. A Hall sensor 64 and a magnet 65 are disposed at the end of the rotor 63. Rotating the steering sensor generates a rotation angle parameter, which is then used to calculate the steering angle of the steering wheel. The steering wheel is then controlled to rotate by the corresponding angle. On one hand, the built-in non-contact Hall sensor can detect and transmit the real-time position of the rotor, inputting a steering position signal to the steering electronic control system, further controlling the steering motor to achieve steering control. On the other hand, it integrates a steering damping function, utilizing the correspondence between the viscosity of the magnetorheological fluid material and the magnetic field to achieve steering damping control.

[0030] The strength of the electromagnetic field is controlled by controlling the input current, which is used to measure the steering angle input to the controller and provide steering torque feedback to the driver.

[0031] Please see Figure 10-12 A forklift steering system control method includes the following steps:

[0032] Step 1: Obtain the forklift speed signal by installing speed sensors at the wheel edges.

[0033] Step 2: Calculate the steering sensor input current signal based on the forklift speed signal. The forklift speed V and the steering sensor input current I satisfy I = a*V + c.

[0034] Step 3: The steering sensor generates rotational damping based on the input current signal. The input current I of the steering sensor and the output torque T generated by the steering sensor satisfy T=b*I+d. According to the electromagnetic and magnetorheological fluid material properties, different current inputs correspond to different electromagnetic fields. Different electromagnetic fields are converted into different viscosities of the magnetorheological fluid material, thereby realizing different steering forces for the driver's hand.

[0035] Step 4: The driver turns the steering control mechanism, which overcomes the damping generated by the steering sensor in Step 3 and drives the steering sensor to rotate.

[0036] Step 5: Control the rotation of the steering wheels by the rotation angle of the steering sensor to complete the forklift steering.

[0037] Example 1

[0038] This embodiment utilizes the steering control system on a folding pallet stacker truck. It collects the forklift's speed signal, converts it into a current value, and sends this current value as input to the steering sensor. The internal coil of the steering sensor converts this current into a corresponding magnetic field. This magnetic field causes the magnetorheological fluid material to produce different viscosities, resulting in different damping values ​​required when the sensor's rotating shaft rotates. This allows for varying steering force required by the driver. This model achieves a steering force of 8N at a vehicle speed of 12km / h and 3N at a vehicle speed of 5km / h.

[0039] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0040] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A forklift truck steering system, characterised in that, It includes a steering control mechanism (1) and a connecting support (2). The steering control mechanism (1) is connected to the upper end of the connecting support (2). The lower end of the connecting support (2) is connected to a steering sensor (6) through a slewing support bearing (3). A mounting base (5) for supporting the slewing support bearing (3) is connected to the outside of the slewing support bearing (3). The steering sensor (6) is a variable damping sensor.

2. The steering system for a fork truck according to claim 1, wherein The steering control mechanism (1) includes a steering support (14) fixedly connected to the upper end of the connecting support (2). The steering support (14) is rotatably connected to a connecting rod (12). The end of the connecting rod (12) away from the steering support (14) is fixedly connected to a steering rudder (11). The rotation axis of the connecting rod (12) on the steering support (14) is arranged perpendicular to the axis of the connecting support (2).

3. A steering system for a forklift according to claim 2, characterized in that, A gas spring (13) for resetting the connecting rod (12) is provided between the connecting rod (12) and the steering support (14).

4. A steering system for a forklift according to claim 2, characterized in that, The connecting support (2) includes a support body (21), which is a cylindrical structure with an open top. The support body (21) is provided with a first connecting hole (22) that is fixedly connected to the steering support (14), and the lower end of the support body (21) is provided with a second connecting hole (23) that is fixedly connected to the slewing bearing.

5. A steering system for a forklift according to claim 1, characterized in that, The slewing support bearing (3) includes a bearing inner ring (31) and a bearing outer ring (32) that are rotatably connected. Both the bearing inner ring (31) and the bearing outer ring (32) are provided with bearing connection holes (33). The mounting base (5) includes a mounting plate (51). The mounting plate (51) is provided with a third connection hole (52) and a fourth connection hole (54). The mounting base (5) is fixedly connected to the bearing connection hole (33) on the bearing outer ring (32) through the fourth connection hole (54).

6. A steering system for a forklift according to claim 1, characterized in that, The mounting base (5) includes a mounting plate (51), and the mounting plate (51) is provided with a limiting block mounting groove (53). A limiting block (4) is fixedly connected in the limiting block mounting groove (53). The limiting block (4) is located on the outside of the connecting support (2). The outer wall of the connecting support (2) is provided with a limiting stop (24) that cooperates with the limiting block (4).

7. A steering system for a forklift according to claim 1, characterized in that, The steering sensor includes a housing (61) and a rotor (63) and a coil (62) disposed within the housing (61). A magnetofluid (66) is disposed between the coil (62) and the rotor (63). A Hall sensor (64) and a magnet (65) are disposed at the end of the rotor (63).

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