Reach Forklift and Its Driving and Parking Brake System

Abstract

The present invention discloses a reach forklift and its driving and parking braking system. The driving and parking braking system of the reach forklift includes: a driving wheel braking assembly including a driving wheel brake; a front wheel braking assembly including a front wheel hydraulic brake and a front wheel hydraulic system connected to the front wheel hydraulic brake; a controller, the signal input ends of the front wheel hydraulic system and the driving wheel brake are respectively communicatively connected to the controller, and the controller can control the start of the front wheel hydraulic system and the driving wheel brake. In this braking system, there are a driving wheel braking assembly and a front wheel braking assembly both controlled by the controller. During parking braking and driving braking, the controller can control the front wheel hydraulic system to drive and start to drive the front wheel hydraulic brake to brake the front wheels, and at the same time control the driving wheel brake to brake the driving wheels, so that three-wheel braking can be achieved during both driving braking and parking braking, greatly improving the safety and reliability of the whole machine.

Description

Technical Field

[0001] The present invention relates to the technical field of forklifts, and particularly to a reach forklift and its driving and parking brake system. Background Art

[0002] The braking system of a reach forklift has two braking forms: parking brake and driving brake. In existing reach forklifts, neither the parking brake nor the driving brake can simultaneously meet the requirement of three-wheel braking for both the load-carrying wheels and the driving wheels. The driving brake and the parking brake only act on the driving wheels. When the parking brake only acts on the driving wheels, the parking braking force of the driving wheels is large, and in case of emergency braking, the driving wheels are prone to lock and lose their roundness. When the driving brake only acts on the driving wheels, the braking distance is long, and due to the single-wheel action, it is easy to have a tail swing.

[0003] Therefore, how to improve the safety and reliability of braking is a technical problem that needs to be solved by those skilled in the art at present. Summary of the Invention

[0004] In view of this, an object of the present invention is to provide a driving and parking brake system for a reach forklift, which has high braking safety and reliability. Another object of the present invention is to provide a reach forklift including the above-mentioned driving and parking brake system for a reach forklift, which has high braking safety and reliability.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A driving and parking brake system for a reach forklift, comprising:

[0007] A driving wheel brake assembly, including a driving wheel brake;

[0008] A front wheel brake assembly, including a front wheel hydraulic brake and a front wheel hydraulic system connected to the front wheel hydraulic brake;

[0009] A controller, the signal input ends of the front wheel hydraulic system and the driving wheel brake are respectively communicatively connected to the controller, and the controller can control the start of the front wheel hydraulic system and the driving wheel brake.

[0010] Preferably, the front wheel hydraulic system includes a telescopic driving device and a brake pump connected between the output end of the telescopic driving device and the front wheel hydraulic brake; the signal input end of the telescopic driving device is communicatively connected to the controller.

[0011] Preferably, the telescopic driving device is an electric push rod.

[0012] Preferably, the driving wheel brake is a mechanical disc brake or an electromagnetic brake.

[0013] Preferably, it further includes a potentiometer for detecting the rotation angle of the brake pedal. The signal output end of the potentiometer is communicatively connected to the controller, and the controller can perform proportional control on the front-wheel hydraulic system according to the signal of the potentiometer.

[0014] Preferably, it further includes a microswitch. The signal output end of the microswitch is communicatively connected to the controller; the microswitch sends different signals to the controller when the brake pedal is in the pedal limit position and the braking position.

[0015] Preferably, it further includes an accelerator for adjusting the traveling speed of the forklift. The signal output end of the accelerator is communicatively connected to the controller; the controller can perform proportional control on the front-wheel hydraulic system according to the signal of the accelerator.

[0016] Preferably, it further includes a front-wheel speed sensor for detecting the rotation speed of the front wheels. The signal output end of the front-wheel speed sensor is communicatively connected to the controller.

[0017] A reach forklift includes the reach forklift driving and parking brake system as described above.

[0018] The reach forklift driving and parking brake system provided by the present invention includes: a drive-wheel braking assembly including a drive-wheel brake; a front-wheel braking assembly including a front-wheel hydraulic brake and a front-wheel hydraulic system connected to the front-wheel hydraulic brake; a controller. The signal input ends of the front-wheel hydraulic system and the drive-wheel brake are respectively communicatively connected to the controller, and the controller can control the start of the front-wheel hydraulic system and the drive-wheel brake.

[0019] In the reach forklift driving and parking brake system, there are a drive-wheel braking assembly and a front-wheel braking assembly both controlled by the controller. During parking braking and driving braking, the controller can control the front-wheel hydraulic system to drive and start to drive the front-wheel hydraulic brake to brake the front wheels, and at the same time control the drive-wheel brake to brake the drive wheels, so that three-wheel braking can be achieved during both driving braking and parking braking, greatly improving the safety and reliability of the whole machine.

[0020] The reach forklift provided by the present invention including the above-mentioned reach forklift driving and parking brake system has relatively high braking safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0022] Figure 1 This is the structural diagram of the front-wheel braking assembly in the first specific embodiment of the travel and parking braking system for the reach forklift provided by the present invention;

[0023] Figure 2 This is the structural diagram of the first specific embodiment of the travel and parking braking system for the reach forklift provided by the present invention;

[0024] Figure 3 This is the structural diagram of the second specific embodiment of the travel and parking braking system for the reach forklift provided by the present invention.

[0025] Reference numerals:

[0026] Front-wheel hydraulic brake 1, brake oil pipe 2, brake pump 3, brake fluid 31, electric push rod 4, controller 5, potentiometer 6, cable 7, drive-wheel brake 8, upper brake pad 81, brake disc 82, lower brake pad 83, brake pedal 9, drive wheel 10, brake spring 11, microswitch 12. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] The core of the present invention is to provide a travel and parking braking system for a reach forklift, and its braking safety and reliability are relatively high. Another core of the present invention is to provide a reach forklift including the above-mentioned travel and parking braking system for a reach forklift, and its braking safety and reliability are relatively high.

[0029] In the first specific embodiment of the travel and parking braking system for the reach forklift provided by the present invention, please refer to Figure 1 and Figure 2 , which includes: a drive-wheel braking assembly, a front-wheel braking assembly, and a controller 5. This travel and parking braking system for a reach forklift can be specifically applied to a stand-up forklift.

[0030] The drive-wheel braking assembly includes a drive-wheel brake 8 to control the braking of the drive wheel. The front-wheel braking assembly includes a front-wheel hydraulic brake 1 and a front-wheel hydraulic system connected to the front-wheel hydraulic brake 1 to control the braking of the front wheels. The front wheels are usually two. Correspondingly, as Figure 1As shown in the figure, a left front wheel hydraulic brake and a right front wheel hydraulic brake are respectively arranged on the left front wheel and the right front wheel. The signal input ends of the front wheel hydraulic system and the drive wheel brake 8 are respectively communicatively connected to the controller 5, and the controller can control the opening and closing of the front wheel hydraulic system and the drive wheel brake 8.

[0031] In this embodiment, a drive wheel braking assembly and a front wheel braking assembly that are both controlled by the controller are provided. During parking braking and driving braking, the controller 5 can control the front wheel hydraulic system to drive and start to drive the front wheel hydraulic brake 1 to brake the front wheels, and at the same time control the drive wheel brake 8 to brake the drive wheel 10, so that three-wheel braking can be achieved during driving braking and parking braking, greatly improving the safety and reliability of the whole machine.

[0032] Furthermore, the front wheel hydraulic system includes a telescopic driving device and a brake pump 3 connected between the output end of the telescopic driving device and the front wheel hydraulic brake 1. The signal input end of the telescopic driving device is communicatively connected to the controller 5. The controller 5 can perform proportional control on the front wheel hydraulic system, specifically perform proportional control on the extension stroke of the output end of the telescopic driving device, so as to control the amount of brake fluid provided by the front wheel hydraulic system to the front wheel hydraulic brake 1, thereby controlling the braking force received by the front wheels. Among them, the controller 5 can achieve proportional control by combining the detection of other components such as the brake pedal in the forklift or the setting of other preset programs. Through proportional control, the braking process can be made gradual, further improving the safety of braking.

[0033] Among them, optionally, the telescopic driving device is an electric push rod 4. When the electric push rod 4 extends, it pushes the brake pump 3 to provide brake fluid to the front wheel hydraulic brake 1, so that the front wheel hydraulic brake 1 performs a braking action. When the electric push rod 4 retracts, the brake fluid of the front wheel hydraulic brake 1 gradually decreases, and the front wheel hydraulic brake 1 gradually releases the braking of the front wheels. Specifically, as Figure 1 shown, both the left front wheel hydraulic brake 1 and the right front wheel hydraulic brake 1 are connected to the brake pump 3, and the brake pump 3 is connected to the electric push rod 4, and unified control of the two front wheels is achieved through the electric push rod 4.

[0034] Furthermore, the drive wheel brake 8 is a mechanical disc brake, and the braking of the drive wheel 10 is achieved through friction. In addition, during the braking process, the controller 5 can perform proportional control on the mechanical disc brake.

[0035] Furthermore, the braking system further includes a potentiometer 6 for detecting the rotation angle of the brake pedal 9, and the signal output end of the potentiometer 6 is communicatively connected to the controller 5. The setting of the potentiometer 6 provides a basis for the proportional control of the controller 5, and the controller 5 can perform proportional control on the front wheel hydraulic system according to the signal of the potentiometer 6.

[0036] Specifically, through the change of the signal of the potentiometer 6, the controller linearly controls the extension stroke of the output end of the electric push rod 4, and further proportionally controls the braking force of the front-wheel hydraulic brake 1: as the brake pedal 9 gradually approaches the braking position (usually when the brake pedal 9 is released), the braking force of the front-wheel hydraulic brake 1 gradually increases; as the brake pedal 9 gradually moves away from the braking position towards the stepping limit position, the braking force of the front-wheel hydraulic brake 1 gradually decreases, realizing proportional braking of the front wheels during vehicle braking. Optionally, the signal range of the potentiometer 6 is 0 - 5V, corresponding to the stroke range of the output end of the electric push rod 4 being 0 - 10mm. Of course, the setting of the signal range of the potentiometer 6 and the telescopic stroke range of the output end of the electric push rod 4 is not limited to this.

[0037] The working principle of the braking system provided in this embodiment is as follows:

[0038] 1) During parking braking, the signal of the potentiometer 6 is 5V, corresponding to the stroke of 10mm of the extended electric push rod 4. After the vehicle is powered off, the electric push rod 4 still remains in this position, realizing simultaneous parking braking of the front wheels and the drive wheels 10;

[0039] 2) During driving, the signal of the potentiometer 6 is 0V, corresponding to the stroke of 0mm of the extended electric push rod 4. When braking during driving, as the signal of the potentiometer 6 changes from 0V to 5V, the electric push rod 4 correspondingly changes from 0mm to 10mm, so that linear braking of the front wheels is achieved; the drive wheels 10 adopt mechanical disc brakes, and the braking force also realizes linear proportional braking as the brake pedal 9 is released, thus realizing three-wheel proportional driving braking simultaneously.

[0040] Obviously, the braking control of the drive wheel brake 8 and the front wheels is not limited to the settings according to the above embodiment. In the second specific embodiment provided by the present invention, please refer to Figure 3 , the drive wheel brake 8 is an electromagnetic brake, which has simple operation and sensitive response.

[0041] In addition, the forward forklift driving and parking braking system further includes a microswitch 12, and the signal output end of the microswitch 12 is communicatively connected to the controller 5. The microswitch 12 sends different signals to the controller 5 when the brake pedal 9 is in the stepping limit position and the braking position.

[0042] Among them, when the brake pedal 9 swings to the stepping limit position, the microswitch 12 will be triggered. At this time, the microswitch 12 sends an open signal to the controller 5; when the external force on the brake pedal 9 is removed and the brake pedal 9 returns to the braking position, the microswitch 12 sends a close signal to the controller 5, so that the controller 5 can control the braking conditions of the front-wheel brake assembly and the drive-wheel brake assembly based on the signal change of the microswitch 12.

[0043] Further, the driving and parking brake system of the reach forklift further includes an accelerator for adjusting the traveling speed of the forklift. The signal output end of the accelerator is communicatively connected to the controller 5. Among them, in the reach forklift, the release action of the accelerator is equivalent to providing a forklift deceleration braking signal. In this embodiment, the signal of the accelerator signal is one of the conditions for the controller 5 to control the start of the front-wheel hydraulic system and the drive-wheel braking assembly.

[0044] For the front-wheel braking, in the driving braking, the conditions for the controller 5 to control the start of the front-wheel hydraulic system include that the accelerator signal drops to no higher than the preset braking voltage (for example, 1V); in the parking braking, the conditions for the controller 5 to control the start of the front-wheel hydraulic system include that the accelerator signal is 0.

[0045] In addition, the controller 5 can perform proportional control on the front-wheel hydraulic system according to the signal of the accelerator. Specifically, when the accelerator signal is between the preset braking voltage and 0V, the extension stroke of the output end of the electric push rod 4 is 0 - 10mm. When the accelerator signal is at the preset braking voltage, the extension stroke of the output end of the electric push rod 4 is 0mm. When the accelerator signal is at 0V, the extension stroke of the output end of the electric push rod 4 is 10mm. As the accelerator signal gradually decreases, the extension stroke of the output end of the electric push rod 4 gradually increases, and the braking force of the front wheel received by the front-wheel hydraulic brake 1 gradually increases.

[0046] Further, the driving and parking brake system of the reach forklift further includes a front-wheel speed sensor for detecting the front-wheel rotation speed, which can be specifically arranged on the rotating shaft of the front wheel. The signal output end of the front-wheel speed sensor is communicatively connected to the controller 5, so that in the front-wheel braking control, the speed detection of the front wheel provides a reference for the front-wheel braking.

[0047] In this embodiment, the controller 5 controls the stroke of the electric push rod 4 according to the signals of the front-wheel speed sensor, the accelerator and the micro switch 12, so as to perform braking control on the front wheel and the drive wheel, further improving the reliability of the braking control.

[0048] Specifically, when the front-wheel speed is 0, the micro switch 12 is in the closed state and the accelerator signal is 0V, the controller controls the start of the front-wheel hydraulic system and the drive-wheel brake 8 to achieve parking braking; when the front-wheel speed is greater than 0, the micro switch 12 is in the open state and after the accelerator signal drops to the preset braking voltage, the controller controls the start of the front-wheel hydraulic system and the drive-wheel brake 8 to achieve driving control.

[0049] Optionally, the change range of the accelerator signal is a 0 - 5V signal. Among them, the preset braking voltage is 1V. When the accelerator signal changes from 1V towards 0V, the electric push rod 4 starts to move. Correspondingly, the extension stroke of the electric push rod 4 changes from 0 to 10mm.

[0050] The working principle of the braking system provided in this embodiment is as follows:

[0051] 1) Parking brake: When the front wheel speed is 0, the microswitch 12 is in the closed state, and at the same time the accelerator signal is 0V. The controller 5 controls the electric push rod 4 to extend a stroke of 10mm and brakes the electromagnetic brake on the drive wheel 10 to achieve three-wheel parking braking, and the same is true after power-off;

[0052] 2) Driving brake: When the front wheel speed is greater than 0 and the brake pedal 9 switch is in the open state, the stroke of the electric push rod 4 is controlled by the accelerator signal. When the accelerator is released and the accelerator signal drops to 1V, the electric push rod 4 starts to extend to brake the front wheel. As the accelerator changes from 1V to 0V, the extension amount of the electric push rod 4 changes from 0 to 10mm. When the accelerator signal becomes 0, the extension amount of the electric push rod 4 reaches 10mm, thus realizing the linear proportional braking of the front wheel during driving; at the same time, the controller 5 controls the electromagnetic brake to brake the drive wheel 10.

[0053] In addition to the above-mentioned driving and parking braking system for reach trucks, the present invention also provides a reach truck, which includes the driving and parking braking system for reach trucks, specifically, it can be the driving and parking braking system for reach trucks provided in any of the above embodiments, and the beneficial effects can be correspondingly referred to the above respective embodiments. For the structures of other parts of the reach truck, please refer to the prior art and will not be elaborated herein.

[0054] It should be noted that when an element is referred to as "fixing" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0055] The orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0057] In the present specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0058] The foregoing has provided a detailed introduction to the reach forklift and its braking system provided by the present invention. Specific examples are used herein to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A front-moving forklift driving and parking braking system, characterized in that, Comprising: A drive wheel braking assembly, including a drive wheel brake (8); A front wheel braking assembly, including a front wheel hydraulic brake (1) and a front wheel hydraulic system connected to the front wheel hydraulic brake (1). The front wheel hydraulic system includes a telescopic driving device and a brake pump (3) connected between the output end of the telescopic driving device and the front wheel hydraulic brake (1). The signal input end of the telescopic driving device is communicatively connected to a controller (5). The telescopic driving device is an electric push rod (4). When the electric push rod (4) extends, it pushes the brake pump (3) to supply brake fluid to the front wheel hydraulic brake (1), causing the front wheel hydraulic brake (1) to perform a braking action. When the electric push rod (4) retracts, the brake fluid of the front wheel hydraulic brake (1) gradually decreases, and the front wheel hydraulic brake (1) gradually releases the braking force on the front wheels; The controller (5), the signal input ends of the front wheel hydraulic system and the drive wheel brake (8) are respectively communicatively connected to the controller (5), and the controller can control the start of the front wheel hydraulic system and the drive wheel brake (8); A microswitch (12), the signal output end of the microswitch (12) is communicatively connected to the controller (5); the microswitch (12) sends different signals to the controller (5) when the brake pedal (9) is in the pedal - pressing limit position and the braking position. Among them, when the brake pedal (9) swings to the pedal - pressing limit position, the microswitch (12) is triggered. At this time, the microswitch (12) sends an open signal to the controller (5). When the external force on the brake pedal (9) is removed and the brake pedal (9) resets to the braking position, the microswitch (12) sends a close signal to the controller (5); An accelerator for adjusting the traveling speed of the forklift, the signal output end of the accelerator is communicatively connected to the controller (5); the controller (5) can perform proportional control on the front wheel hydraulic system according to the signal of the accelerator; A front wheel speed sensor for detecting the front wheel speed, the signal output end of the front wheel speed sensor is communicatively connected to the controller (5); Wherein, when the front wheel speed is 0, the microswitch (12) is in the closed state and the signal of the accelerator is 0V, the controller controls the start of the front wheel hydraulic system and the drive wheel brake (8) to achieve parking braking; Wherein, when the front wheel speed is greater than 0, the microswitch (12) is in an open state and the signal of the accelerator drops to a preset braking voltage, the controller controls the front wheel hydraulic system and the drive wheel brake (8) to start to achieve driving control. When the signal of the accelerator is between the preset braking voltage and 0V, the extension stroke of the output end of the electric push rod (4) is 0 - 10mm. Among them, when the signal of the accelerator is at the preset braking voltage, the extension stroke of the output end of the electric push rod (4) is 0mm. When the signal of the accelerator is at 0V, the extension stroke of the output end of the electric push rod (4) is 10mm. When the signal of the accelerator gradually decreases, the extension stroke of the output end of the electric push rod (4) gradually increases, and the braking force of the front wheel hydraulic brake (1) on the front wheel gradually increases.

2. The front-moving forklift traveling and parking braking system according to claim 1, characterized in that, The drive wheel brake (8) is a mechanical disc brake.

3. The front-moving forklift driving and parking brake system according to claim 1, characterized in that, The drive wheel brake (8) is an electromagnetic brake.

4. The front-moving forklift driving and parking brake system according to claim 1, characterized in that, It further includes a potentiometer (6) for detecting the rotation angle of the brake pedal (9). The signal output end of the potentiometer (6) is communicatively connected to the controller (5), and the controller (5) can perform proportional control on the front wheel hydraulic system according to the signal of the potentiometer (6).

5. A reach forklift, characterized in that, It includes the forward forklift driving and parking braking system according to any one of claims 1 to 4.

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