CN213799106U

CN213799106U - Four-fulcrum electric forklift steering system applying novel steering mode

Info

Publication number: CN213799106U
Application number: CN202023124029.0U
Authority: CN
Inventors: 吕昊; 俞建良; 李明辉; 陈俊; 师全红
Original assignee: Hangcha Group Co Ltd
Current assignee: Hangcha Group Co Ltd
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2021-07-27
Anticipated expiration: 2030-12-22

Abstract

The utility model discloses an use four fulcrums electric fork-lift truck a steering system of novel mode that turns to relates to a steering system technical field, and this a steering system includes two front wheels and two rear wheels to and the steering axle assembly, the steering axle assembly includes crane span structure, knuckle, swizzle and support piece, wherein: each front wheel is connected with a walking motor; two ends of the bridge frame are respectively and rotatably connected with a main pin, and the central axis of the main pin is a vertical axis; each main pin is driven to rotate by a steering knuckle, and the main pins and the steering knuckles are positioned above the rear wheels; each kingpin is fixedly connected to a hub axle of a rear wheel via a respective support element. The utility model discloses can make four fulcrum electric fork truck have great corner scope, can realize the original place rotation even to four fulcrum fork truck mobility and trafficability characteristic have been strengthened.

Description

Four-fulcrum electric forklift steering system applying novel steering mode

Technical Field

The application relates to the technical field of steering systems, in particular to a four-fulcrum electric forklift steering system applying a novel steering mode.

Background

Forklifts play a very important role in logistics systems of enterprises, being the prime force among materials handling equipment. Particularly, with the rapid development of the world economy, the material handling of most enterprises has been separated from the original manual handling, and is replaced by the mechanical handling mainly based on a forklift. In forklift operation, steering is an operation that is frequently performed.

Referring to fig. 1, a conventional four-pivot electric forklift is driven by a single motor and a gearbox to drive two tires to rotate, a bridge of a steering axle is located between the two tires, and a steering knuckle is close to a hub. In this configuration, although the differential mechanism is included in the drive axle to allow the two tires to rotate at different speeds at the same time, it is difficult to achieve rotation of the two tires in opposite directions, and in the extreme case, one tire does not rotate while the other tire rotates. Therefore, the turning center point of the forklift in the maximum turning is often positioned at the outer side of the center of the front wheel tire (in the limit condition, at the center of the front wheel tire), and the inner and outer turning angles of the matched steering axle are below 90 degrees. In such an arrangement, if the rotation angle is too large, the tire assembly and the axle body interfere, so that the rotation angle range is limited, and the forklift can not realize pivot steering generally below 90 degrees.

Therefore, the existing four-fulcrum forklift has the problems of small turning angle and large turning radius.

SUMMERY OF THE UTILITY MODEL

In view of this, the purpose of the present application is to provide a four-pivot electric forklift steering system applying a novel steering mode, which has a large rotation angle range and can even realize pivot rotation, so that the mobility and the trafficability of the four-pivot forklift are enhanced. The specific scheme is as follows:

the utility model provides a four fulcrum electric fork-lift steering system, includes two front wheels and two rear wheels to and steering axle assembly, steering axle assembly includes crane span structure, knuckle, king pin and support piece, wherein:

each front wheel is connected with a walking motor;

two ends of the bridge frame are respectively and rotatably connected with one main pin, and the central axis of each main pin is a vertical axis;

each main pin is driven to rotate by one steering knuckle, and the main pin and the steering knuckle are located above the rear wheel;

each main pin is fixedly connected with a hub shaft of one rear wheel through one supporting piece.

Optionally, the supporting member is a connecting bent plate, a first connecting end of the connecting bent plate is fixedly connected with the hub shaft, and a second connecting end is located above the rear wheel and fixedly connected with the pin shaft.

Optionally, in the connecting bent plate, a vertical support portion between the first connecting end and the second connecting end is located inside the rear wheel.

Optionally, the center axis of the kingpin is perpendicular to and coplanar with the center axis of the hub axle.

Optionally, the two ends of the bridge frame are respectively provided with a connecting claw, the connecting claw comprises a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are both rotatably connected with the kingpin, and the knuckle is located between the first connecting portion and the second connecting portion.

Optionally, a first bearing is disposed between the first connecting portion and the kingpin; a second bearing is arranged between the second connecting part and the main pin, and sealing rings are arranged on two sides of the second bearing; the first connecting portion is located above the second connecting portion and is provided with an oil storage cavity for storing lubricating oil.

Optionally, the two steering knuckles are driven to rotate by a steering oil cylinder;

and/or the kingpin is in splined connection with the steering knuckle.

Optionally, a vehicle controller and an angle sensor for measuring the steering angle of the rear wheel;

and the motor controllers connected with the two walking motors are in signal connection with the angle sensors so as to control the rotating speed of the front wheels through rear wheel steering angle signals fed back by the angle sensors.

The four-fulcrum electric forklift steering method applying the novel steering mode is suitable for the four-fulcrum electric forklift steering system applying the novel steering mode, and comprises the following steps:

step S1: the steering of the rear wheels is adjusted through a steering wheel;

step S2: the angle sensor converts the detected steering angle of the rear wheel into a rear wheel steering angle signal and feeds the rear wheel steering angle signal back to the motor controller, the motor controller is connected with two walking motors, and the two walking motors are respectively used for controlling the steering and the rotating speed of one front wheel;

step S3: the motor controller adjusts the steering and rotational speed with the front wheels by the rear wheel steering angle signal and the vehicle travel speed.

Wherein:

when the rear wheel steering angle is larger than a first preset value and smaller than or equal to a second preset value, the rear wheel steering angle signal is larger than or equal to a first signal value and smaller than or equal to a second signal value, the motor controller controls the two walking motors to rotate in opposite directions, and the rotating speed of the walking motor positioned at the outer corner is larger than that of the walking motor positioned at the inner corner;

when the rear wheel steering angle is larger than a second preset value, the rear wheel steering angle signal is larger than a second signal value, the two motor controllers control the traveling motors to rotate in opposite directions, and the rotating speeds are equal.

According to the above technical scheme, the utility model provides an use four fulcrums electric fork truck the a steering system of novel mode that turns to, this use four fulcrums electric fork truck the a steering system of novel mode that turns to has following beneficial effect:

a. because two front wheels of the forklift are respectively connected with a walking motor, the rotating speed of the forklift is respectively adjustable, and the steering can be the same or different. Because two front wheels can turn to can be different to can reduce fork truck's turning radius, reach and show the purpose that promotes fork truck mobility and trafficability characteristic.

And b, because the main pin and the steering knuckle are positioned above the rear wheel, the steering knuckle and the bridge frame are far away from the rear wheel, and the rear wheel can freely rotate within any angle (the steering angle of each rear wheel can exceed 90 degrees). Through the change to the front wheel and the rear wheel driving system, the four-fulcrum forklift can have a larger rotation angle range, even can rotate in situ, and the maneuverability and the trafficability of the four-fulcrum forklift are enhanced.

Further, in the steering system:

the steering angle of the rear wheel is fed back to the motor controller through the angle sensor, so that the rotation angle detection and the automatic turning deceleration can be realized;

the connecting rod is driven by the telescopic action of the steering oil cylinder, so that the connecting rod drives the steering knuckle to rotate, the main pin synchronously rotates and drives the rear wheel to rotate when the main pin and the steering knuckle are connected through the spline, and the tire rotates to effectively avoid being touched by an irrelevant object so as to stably steer at an angle larger than 90 degrees;

the rotating speeds of the corresponding walking motors are respectively controlled by the two motor controllers, so that the rotating speeds of the two corresponding front wheels are respectively controlled, and the effect of stable steering of the forklift is achieved;

through the arrangement of the steering axle with stable steering of more than 90 degrees, the turning center of the forklift is positioned at the inner sides of the centers of the tires on the two sides of the front wheel, when the sum of the internal rotation angles theta 1 and theta 2 is 180 degrees, the turning center is positioned at the midpoint of the connecting line of the two front wheels, the steering directions of the two front wheels are opposite, the rotating speeds of the two front wheels are equal, and the effect of pivot steering of the forklift is achieved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a steering system of an electric forklift in the prior art;

fig. 2 is a schematic view of a steering principle of a four-fulcrum electric forklift steering system using a novel steering mode according to an embodiment of the present invention;

fig. 3 is a schematic view of an overall structure of a four-fulcrum electric forklift steering system using a novel steering mode according to an embodiment of the present invention;

fig. 4 is a schematic view of an assembly structure of a steering axle assembly and a rear wheel according to an embodiment of the present invention;

fig. 5 is a cross-sectional view of the steering axle assembly and the rear wheel at the connection position according to the embodiment of the present invention.

Description of reference numerals:

1. a front wheel; 2. a gearbox; 3. a traveling motor;

4. a rear wheel; 5. a motor controller; 6. a steering axle assembly (which may be referred to simply as a steering axle);

61. a bridge frame; 611. a kingpin; 62. an oil cylinder; 63. a connecting rod;

64. an angle sensor; 65. a knuckle; 66. a support (i.e., a connecting bent plate);

67. a hub shaft; 68. a hub.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 2 to 3, the embodiment of the present invention provides a four-pivot electric forklift steering system using a novel steering mode, the system includes two front wheels 1 and two rear wheels 4, and a steering axle assembly 6, and the steering axle assembly 6 includes a bridge frame 61, a knuckle 65, a kingpin 611, and a support 66. Wherein: each front wheel 1 is connected with a walking motor 3; two ends of the bridge frame 61 are respectively connected with a main pin 611 in a rotating manner, and the central axis of the main pin 611 is a vertical axis; each kingpin 611 is driven to rotate by a knuckle 65, and the kingpin 611 and the knuckle 65 are both located above the rear wheel 3; each kingpin 611 is fixedly connected to a hub axle 67 of a rear wheel (4) via a respective support 66.

In this four fulcrum electric fork truck a steering system who uses novel mode of turning to:

Specifically, the center axis of the kingpin 611 is perpendicular to and coplanar with the center axis of the hub axle 67.

Specifically, referring to fig. 4 and 5, the supporting member 66 is a connecting bent plate, a first connecting end of the connecting bent plate is fixedly connected to the hub axle 67, and a second connecting end is located above the rear wheel and is fixedly connected to the pin 611. Preferably, in the connecting bent plate, a vertical support portion between the first connecting end and the second connecting end is located inside the rear wheel 4.

Specifically, referring to fig. 5, the two ends of the bridge frame 61 are respectively provided with a connecting claw, the connecting claw includes a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are both rotatably connected with the main pin 611, and the knuckle 65 is located between the first connecting portion and the second connecting portion.

Wherein a first bearing is arranged between the first connecting part and the main pin 611; a second bearing is arranged between the second connecting part and the main pin 611, and sealing rings are arranged on two sides of the second bearing; the first connecting portion is located the top of second connecting portion, and is provided with the oil storage chamber that is used for storing lubricating oil.

Specifically, referring to fig. 3 and 4, the two steering knuckles 65 are driven to rotate by the steering cylinders 62. Wherein, the connecting rods 63 at the two ends of the oil cylinder 62 are respectively connected with a steering knuckle 65, and the main pin 611 is in spline connection with the steering knuckle 65.

Further, referring to fig. 3 and 4, in the steering system of the four-fulcrum electric forklift applying the novel steering mode, a vehicle controller and an angle sensor 64 for measuring the steering angle of the rear wheel 4 are further included; the motor controllers 5 connected with the two traveling motors 3 are in signal connection with the angle sensor 64 so as to control the rotating speed of the front wheels 1 through rear wheel turning angle signals fed back by the angle sensor 64.

Furthermore, the utility model discloses specific embodiment still provides a four fulcrum electric fork truck steering method, and this method is applicable to the above-mentioned four fulcrum electric fork truck steering system who uses novel mode of turning to. The steering method of the four-fulcrum electric forklift mainly comprises the following steps:

step S1: the steering of the rear wheel 4 is adjusted through a steering wheel;

step S2: the angle sensor 64 converts the detected steering angle of the rear wheel 4 into a rear wheel steering angle signal and feeds the rear wheel steering angle signal back to the motor controller 5, the motor controller 5 is connected with the two traveling motors 3, and the two traveling motors 3 are respectively used for controlling the steering and the rotating speed of one front wheel 1;

step S3: the motor controller 5 adjusts the steering and rotation speed with the front wheels 1 by the rear wheel rotation angle signal and the vehicle traveling speed.

Wherein:

when the steering angle of the rear wheel 4 is greater than a first preset value and less than or equal to a second preset value, the rear wheel steering angle signal is greater than or equal to a first signal value and less than or equal to a second signal value, the motor controller 5 controls the two walking motors 3 to rotate in opposite directions, and the rotating speed of the walking motor 3 positioned at the outer corner is greater than that of the walking motor 3 positioned at the inner corner, so that a large-angle steering angle is realized;

when the steering angle of the rear wheel 4 is larger than the second preset value, the rear wheel steering signal is larger than the second signal value, the motor controller 5 controls the two traveling motors 3 to rotate in opposite directions, and the rotating speeds are equal, so that pivot steering is realized.

To sum up, the utility model discloses in the four fulcrums electric fork-lift steering system of the novel mode that turns to of application that the embodiment provides, every front wheel 1 is connected with a walking motor 3 respectively, and walking motor 3 plays the effect of the corresponding front wheel 1 rotational speed of control, and through the rotational speed of controlling corresponding walking motor 3 respectively by two machine controller 5 to control the rotational speed of two corresponding front wheels 1 respectively, thereby reach the stable effect that turns to of fork truck. Meanwhile, each front wheel 1 is connected with a gearbox 2 so as to achieve the purpose of effectively controlling the speed and torque change of the front wheels 1. It should be noted that the traveling motor 3 is connected with a motor controller 5; and the rear wheel 4 is connected with a steering axle 6 for realizing an inner corner larger than 90 degrees. Therefore, the turning center of the forklift is positioned at the inner side of the centers of the tires at two sides of the front wheel 1, the included angle between the axis of the rear wheel 4 positioned at the left side and the axis of the front wheel 1 positioned at the right side is theta 1, and the theta 1 is larger than 90 degrees; the included angle between the axis of the rear wheel 4 on the right side and the axis of the front wheel 1 on the right side is theta 2, when the sum of theta 1 and theta 2 is 180 degrees, the turning center of the steering system is located in the middle of the two front wheels 1, so that pivot steering of the forklift is achieved, and due to the fact that the left and right rotating directions of the rear wheel 4 are opposite, the turning radius of the forklift is reduced, and the purpose of remarkably improving the maneuverability and the trafficability of the forklift is achieved.

It should be mentioned that each steer axle 6 is provided with an angle sensor 64 for monitoring the steering angle of the respective rear wheel 4. The angle sensor 64 is connected to the motor controller 5, and transmits the monitored angle sensing feedback value to the motor controller 5. Therefore, the steering angle of the rear wheel 4 is fed back to the motor controller 5 by the angle sensor 64, and the turning angle detection and the automatic turning deceleration are realized.

As shown in fig. 4 and 5, the steering axle 6 includes a bridge 61. A steering cylinder 62 is provided at the center of the bridge 61 for driving the rotation of the rear wheel 4. A connecting rod 63 is provided at both ends of the steering cylinder 62 for connecting with the rear wheel 4 and effecting transmission of force and driving rotational movement of the rear wheel 4. It should be noted that two rear wheels 4 are respectively located at the lower sides of two ends of the bridge frame 61, and each rear wheel 4 is connected with a connecting bent plate 66. The upper end of the connecting bent plate 66 is provided with a main pin 611 rotatably connected with the bridge frame 61. The kingpin 611 is fitted over a knuckle 65 connected to the corresponding link 63, so that the force transmitted from the steering cylinder 62 to the link 63 acts on the corresponding rear wheel 4 via the knuckle 65 and drives the rotation. In order to stably connect the rear wheels 4 to the bridge 61, a hub shaft 67 is provided at a lower end of the connecting bent plate 66, and a hub 68 matching with the corresponding rear wheel 4 is fixedly connected to the hub shaft 67. Meanwhile, a spline is provided between the knuckle 65 and the kingpin 611, and rotates in synchronization. The kingpin 611, the connecting bent plate 66 and the hub shaft 67 are welded to each other, so that a stable connection state can be achieved. Therefore, the connecting rod 63 is driven by the extension and contraction of the steering cylinder 62, so that the connecting rod 63 drives the steering knuckle 65 to rotate, and further when the main pin 611 and the steering knuckle 65 are connected through the spline, the purpose that the main pin 611 synchronously rotates and drives the rear wheel 4 to rotate is achieved, and at the moment, the tire rotates to effectively avoid being touched by an irrelevant object, so that stable steering larger than 90 degrees is performed.

When the four-fulcrum electric forklift steering system applying the novel steering mode is used, the control is required to be carried out through the motor controller 5, and the control strategy of the motor controller 5 is to firstly receive an angle sensing feedback value and calculate a steering angle; after receiving the traveling speed value, calculating the rotating speed required by the corresponding front wheel 1 according to the steering angle; and outputs the calculated rotating speed to the traveling motor 3 to control the corresponding rotating speed of the front wheel 1.

It should be noted that, in the control strategy of the motor controllers 5, when the steering angle reaches the set initial threshold, the two motor controllers 5 respectively control the corresponding traveling motors 3 to rotate in opposite directions; and when the angle sensing feedback value reaches a set limit threshold value, the two motor controllers 5 respectively control the corresponding walking motors 3 to rotate at the same rotating speed in opposite directions so as to achieve the purpose of in-situ steering of the forklift.

In conclusion, the steering axle 6 which stably steers at an angle greater than 90 degrees is arranged, so that the turning center of the forklift is positioned at the inner sides of the centers of the tires on both sides of the front wheel 1, and when the sum of the internal rotation angles theta 1 and theta 2 is 180 degrees, the turning center is positioned at the midpoint of the connecting line of the two front wheels 1, and at the moment, the steering directions of the two front wheels 1 are opposite and the rotating speeds of the two front wheels 1 are equal, so that the effect of steering the forklift in situ is realized; and because the left and right sides rotation direction of rear wheel 4 is opposite, and then reduced fork truck's turning radius, reach the purpose that shows promotion fork truck mobility and trafficability characteristic.

References to "first" and "second" in this application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that the embodiments described herein may be practiced otherwise than as specifically illustrated or described herein. Furthermore, the terms "comprises" and "comprising," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, or apparatus.

It should be noted that the descriptions in this application referring to "first", "second", etc. are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present application.

The principle and the implementation of the present application are explained herein by applying specific examples, and the above description of the embodiments is only used to help understand the method and the core idea of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A four-pivot electric forklift steering system applying a novel steering mode, which is characterized by comprising two front wheels (1) and two rear wheels (4) and a steering axle assembly (6), wherein the steering axle assembly (6) comprises a bridge (61), a steering knuckle (65), a kingpin (611) and a support (66), wherein:

each front wheel (1) is connected with a walking motor (3) respectively;

two ends of the bridge frame (61) are respectively connected with one main pin (611) in a rotating mode, and the central axis of the main pin (611) is a vertical axis;

each kingpin (611) is driven to rotate by one steering knuckle (65), and the kingpin (611) and the steering knuckle (65) are located above the rear wheel (4);

each kingpin (611) is fixedly connected to a hub axle (67) of one of the rear wheels (4) via one of the supports (66).

2. The four-fulcrum electric forklift steering system applying the novel steering mode according to claim 1, wherein the supporting member (66) is a connecting bent plate, a first connecting end of the connecting bent plate is fixedly connected with the hub shaft (67), and a second connecting end of the connecting bent plate is fixedly connected with the kingpin (611) above the rear wheel.

3. The four-fulcrum electric forklift steering system applying the novel steering mode according to claim 2, wherein in the connecting bent plate, a vertical supporting portion between the first connecting end and the second connecting end is located inside the rear wheel (4).

4. The four-fulcrum electric fork lift steering system applying the novel steering mode as claimed in claim 2, wherein a central axis of the kingpin (611) is perpendicular to and coplanar with a central axis of the hub axle (67).

5. The four-fulcrum electric forklift steering system applying the novel steering mode according to claim 2, wherein two ends of the bridge (61) are respectively provided with a connecting claw, the connecting claws comprise a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion are both rotatably connected with the kingpin (611), and the steering knuckle (65) is located between the first connecting portion and the second connecting portion.

6. The four-fulcrum electric forklift steering system applying the novel steering mode according to claim 5, wherein a first bearing is arranged between the first connecting part and the main pin (611); a second bearing is arranged between the second connecting part and the main pin (611), and sealing rings are arranged on two sides of the second bearing; the first connecting portion is located above the second connecting portion and is provided with an oil storage cavity for storing lubricating oil.

7. The four-fulcrum electric forklift steering system applying the novel steering mode according to any one of claims 1 to 6, wherein the two steering knuckles (65) are driven to rotate by a steering oil cylinder (62);

and/or a spline connection between the kingpin (611) and the steering knuckle (65).

8. The four-fulcrum electric forklift steering system applying the novel steering mode according to any one of claims 1 to 6, further comprising a vehicle controller and an angle sensor (64) for measuring a steering angle of the rear wheel (4);

and the motor controllers (5) connected with the two walking motors (3) are in signal connection with the angle sensor (64) so as to control the rotating speed of the front wheel (1) through a rear wheel rotating angle signal fed back by the angle sensor (64).