CN113635966B - Four-wheel drive slip steering chassis hydraulic control system - Google Patents
Four-wheel drive slip steering chassis hydraulic control system Download PDFInfo
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- CN113635966B CN113635966B CN202111039205.7A CN202111039205A CN113635966B CN 113635966 B CN113635966 B CN 113635966B CN 202111039205 A CN202111039205 A CN 202111039205A CN 113635966 B CN113635966 B CN 113635966B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/062—Details, component parts
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/07—Supply of pressurised fluid for steering also supplying other consumers ; control thereof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/08—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by type of steering valve used
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Arrangement And Driving Of Transmission Devices (AREA)
Abstract
The invention discloses a four-wheel drive slip steering chassis hydraulic control system, which comprises: the left oil pump is communicated with the left front wheel hydraulic motor and the left rear wheel hydraulic motor through the left flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the left front wheel and the left rear wheel; the right oil pump is respectively communicated with the right front wheel hydraulic motor and the right rear wheel hydraulic motor through a right flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the right front wheel and the right rear wheel. When needs pivot are turned to, the hydraulic motor of steerable left and right sides rotates towards opposite direction respectively, can make the vehicle pivot turn to, and zero turning radius can be realized to this mode of turning to, not only can improve the operating efficiency, can also adapt to comparatively narrow operational environment.
Description
Technical Field
The invention relates to the technical field of engineering machinery, in particular to a four-wheel drive slip steering chassis hydraulic control system.
Background
The chassis steering system of the current wheel type walking machinery generally adopts modes such as front wheel steering, rear wheel steering, articulated steering and the like, and the steering modes not only have certain turning radius, but also have poor steering flexibility, so that the chassis steering system is difficult to be suitable for scenes with narrow working space.
The conventional steering system usually needs parts such as a steering axle, a steering oil cylinder, a steering gear and the like, so the structure is more complex and the cost is higher.
The existing sliding type steering system is mostly used for a loader, a walking and steering hydraulic system of the existing sliding type steering system mostly adopts a double-closed type hydraulic system consisting of two pumps and two motors, the two walking pumps and an auxiliary pump are connected in series and then are connected with an output shaft of an engine, the two walking motors are respectively arranged at the left side and the right side of a vehicle body, and the walking motors at the two sides respectively drive respective front wheels and rear wheels through chains, gear sets or transmission shafts.
The design scheme has the following defects:
1. the motors on the left side and the right side respectively drive the front wheel and the rear wheel through chains, so that the stability is poor at high speed, the high-speed chain type gear jumping mechanism is not suitable for working conditions of large load change and rapid reversal, and the gear jumping is easy to occur after abrasion;
2. the chain wheel oil tanks on the left side and the right side occupy a large part of space of the chassis, so that the processing difficulty is increased;
3. only two drive motors are provided, and the drive torque is small.
Disclosure of Invention
The invention aims to provide a four-wheel drive slip steering chassis hydraulic control system which can reduce the turning radius and further improve the adaptability of the four-wheel drive slip steering chassis hydraulic control system to narrow environments.
In order to solve the technical problems, the invention provides the following technical scheme:
a four wheel drive skid steer chassis hydraulic control system comprising: the left oil pump is respectively communicated with the left front wheel hydraulic motor and the left rear wheel hydraulic motor through the left flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the left front wheel and the left rear wheel; and the right oil pump is communicated with the right front wheel hydraulic motor and the right rear wheel hydraulic motor respectively through the right flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the right front wheel and the right rear wheel.
Preferably, the vehicle brake system further comprises an auxiliary oil pump, an energy accumulator and a brake valve, wherein the auxiliary oil pump is communicated with the brake valve, the energy accumulator is connected to an oil path connected with the auxiliary oil pump and the brake valve, and the brake valve is used for braking the left front wheel, the left rear wheel, the right front wheel and the right rear wheel.
Preferably, the oil pump further comprises an electric proportional reversing valve, and the electric proportional reversing valve is communicated with an oil outlet pipeline of the auxiliary oil pump.
Preferably, the system further comprises an overflow valve connected with the electric proportional reversing valve in parallel, and the overflow valve is communicated with an oil outlet pipeline of the auxiliary oil pump.
Preferably, the overflow valve is communicated with the oil tank through a radiator and/or a bypass check valve.
Preferably, the hydraulic control system further comprises a pressure reduction overflow valve, the auxiliary oil pump is respectively connected with the left flow distribution and collection valve and the right flow distribution and collection valve through the pressure reduction overflow valve, and the auxiliary oil pump is also respectively connected with the left front wheel hydraulic motor, the left rear wheel hydraulic motor, the right front wheel hydraulic motor and the right rear wheel hydraulic motor through the pressure reduction overflow valve.
Preferably, the vehicle further comprises a parking valve, the parking valve is connected to an oil path between the accumulator and the brake valve, and the parking valve is respectively connected with the left front wheel, the left rear wheel, the right front wheel and the right rear wheel.
Preferably, an oil inlet pipeline of the parking valve is connected with a pre-valve pressure sensor, and an oil outlet pipeline of the parking valve is connected with a post-valve pressure sensor.
Preferably, the left oil pump and the right oil pump are variable displacement plunger pumps.
Compared with the prior art, the technical scheme has the following advantages:
1. through the left hydraulic motor of left oil pump drive to and through the hydraulic motor on right oil pump drive right side, saved drive mechanism such as chain, sprocket or gear box, can reduce the chassis welding process degree of difficulty, practiced thrift manufacturing cost.
2. When needs pivot are turned to, the hydraulic motor of steerable left and right sides rotates towards opposite direction respectively, can make the vehicle pivot turn to, and zero turning radius can be realized to this mode of turning to, not only can improve the operating efficiency, can also adapt to comparatively narrow operational environment.
3. Through the electric proportional reversing valve and the overflow valve, the starting load of the engine can be reduced, and the hydraulic impact with a hydraulic system can be reduced.
Drawings
In order to more clearly illustrate the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a hydraulic schematic diagram of a hydraulic control system for a four-wheel drive skid steer chassis according to an embodiment of the present invention.
The reference numbers are as follows:
the system comprises an oil tank 1, an oil absorption filter 2, a radiator 3, a bypass check valve 4, an electric proportional reversing valve 5, an overflow valve 6, an auxiliary gear pump 7, a variable plunger pump 8, a throttle valve 9, a brake valve 10, a pre-valve pressure sensor 11, a parking valve 12, a post-valve pressure sensor 13, an energy accumulator 14, a check valve 15, a damping valve 16, a flow dividing and collecting valve 17, a pressure reducing overflow valve 18, a wheel reduction gear 19 and a variable plunger motor 20.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. The invention can be embodied in many different forms than those described herein and those skilled in the art will appreciate that the invention is susceptible to similar forms of embodiment without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
Referring to fig. 1, fig. 1 is a hydraulic schematic diagram of a four-wheel drive skid steer chassis hydraulic control system according to an embodiment of the present invention.
The invention provides a four-wheel drive slip steering chassis hydraulic control system, which comprises an oil tank 1, an oil pump, a flow dividing and collecting valve 17, a hydraulic motor and a connecting pipeline, wherein the oil pump is divided into a left oil pump and a right oil pump, the flow dividing and collecting valve 17 is divided into a left flow dividing and collecting valve and a right flow dividing and collecting valve, the hydraulic motor is divided into a left front wheel hydraulic motor, a left rear wheel hydraulic motor, a right front wheel hydraulic motor and a right rear wheel hydraulic motor, the left oil pump and the right oil pump are preferably variable plunger pumps 8, each hydraulic motor is also preferably variable plunger motors 20, the left oil pump and the right oil pump are respectively communicated with the oil tank 1, and the left oil pump is respectively communicated with the left front wheel hydraulic motor and the left rear wheel hydraulic motor through the left flow dividing and collecting valve so as to control the rotating speed and the rotating direction of the left front wheel and the left rear wheel; the right oil pump is respectively communicated with the right front wheel hydraulic motor and the right rear wheel hydraulic motor through a right flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the right front wheel and the right rear wheel. Each hydraulic motor is connected with the corresponding wheel through a wheel reduction box 19 respectively to reach the purposes of speed reduction and torque increase, the left hydraulic motor is driven through the left oil pump, and the right hydraulic motor is driven through the right oil pump, so that transmission mechanisms such as chains, chain wheels or gear boxes are omitted, the difficulty of the chassis welding process can be reduced, and the production cost is saved. When the vehicle needs to run linearly, the left oil pump and the right oil pump are controlled to work so as to respectively supply oil to the hydraulic motors on the left side and the right side, and the vehicle can move forwards or backwards; when steering is needed, the rotating speed of the hydraulic motors on the left side and the right side can be controlled to generate speed difference, so that steering is realized; when needs pivot are turned to, the hydraulic motor of steerable left and right sides rotates towards opposite direction respectively, can make the vehicle pivot turn to, and zero turning radius can be realized to this mode of turning to, not only can improve the operating efficiency, can also adapt to comparatively constrictive operational environment.
The brake system further comprises an auxiliary oil pump, an energy accumulator 14 and a brake valve 10, wherein the auxiliary oil pump is preferably an auxiliary gear pump 7, the auxiliary oil pump is communicated with the brake valve 10, an oil path connected with the auxiliary oil pump and the brake valve 10 is provided with a damping valve 16 and a one-way valve 15, the energy accumulator 14 is connected to the oil path connected with the auxiliary oil pump and the brake valve 10, a throttle valve 9 is further connected to the position, located between the energy accumulator 14 and the one-way valve 15, of the oil path, the throttle valve 9 is used for unloading during maintenance, the auxiliary oil pump absorbs oil in an oil tank 1 through an oil absorption filter 2, the brake system further comprises a parking valve 12, the parking valve 12 is connected to the oil path between the energy accumulator 14 and the brake valve 10, the parking valve 12 is respectively connected with the left front wheel, the left rear wheel, the right rear wheel and the right rear wheel, an oil inlet pipeline of the parking valve 12 is connected with a valve front pressure sensor 11, an oil outlet pipeline of the parking valve 12 is connected with a valve rear pressure sensor 13, and the brake valve 10 is used for braking the left front wheel, the left rear wheel, the right rear wheel and the right wheel. The auxiliary oil pump may charge the accumulator 14, and the accumulator 14 may be used to provide emergency pressure to the parking and braking system, and may allow the parking valve 12 to actuate, i.e., allow parking to be released, after the charging pressure reaches a set value, i.e., after the charging pressure reaches a set value of the pre-valve pressure sensor 11. The pressure sensor 13 displays the pressure of the parking valve 12, and when the pressure is smaller than a set value, the hydraulic system sends out an alarm signal.
Furthermore, the system also comprises an electric proportional reversing valve 5, and the electric proportional reversing valve 5 is communicated with an oil outlet pipeline of the auxiliary oil pump. When the vehicle runs in a straight line, before the engine is started, the electric proportional reversing valve 5 is in an electrified state, and at the moment, the starting load is small, so that the starting of the engine is facilitated, and the hydraulic impact on a hydraulic system is small; after the start, the electric proportional directional valve 5 is in a power-off state, and the system pressure gradually rises.
In addition, the device also comprises an overflow valve 6 connected with the electric proportional reversing valve 5 in parallel, and the overflow valve 6 is communicated with an oil outlet pipeline of the auxiliary oil pump. During the rise of the system pressure, if the system pressure reaches the setting of the overflow valve 6, the excess hydraulic oil flows back to the oil tank 1. The overflow valve 6 is communicated with the oil tank 1 through the radiator 3 and/or the bypass check valve 4, the high-temperature hydraulic oil can be cooled through the radiator 3, and the radiator 3 can be protected through the bypass check valve 4.
In addition, the electric proportional reversing valve 5 and the overflow valve 6 can be replaced by a pilot type plate-type electromagnetic overflow valve which is communicated with an oil outlet pipeline of the auxiliary oil pump, and the purpose of reducing the starting torque of the engine can be achieved.
Furthermore, the hydraulic control system also comprises a pressure reducing overflow valve 18, the auxiliary oil pump is respectively connected with the left flow distributing and collecting valve and the right flow distributing and collecting valve through the pressure reducing overflow valve 18, and the auxiliary oil pump is also respectively connected with the left front wheel hydraulic motor, the left rear wheel hydraulic motor, the right front wheel hydraulic motor and the right rear wheel hydraulic motor through the pressure reducing overflow valve 18. Specifically, a damping valve 16 is arranged between the auxiliary oil pump and the pressure-reducing overflow valve 18, hydraulic oil is divided into a left path and a right path after passing through the pressure-reducing overflow valve 18, the left path is divided into two branches, one of the branches is provided with a check valve 15, one branch is connected with an oil path between the left oil pump and the left front wheel hydraulic motor, the other branch is connected with an oil path between the left oil pump and the left flow distributing and collecting valve, the right path and the left path are the same, and oil can be supplemented to the low-pressure side of the hydraulic system through the pressure-reducing overflow valve 18.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising one of 8230; \8230;" 8230; "does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (4)
1. A four wheel drive skid steer chassis hydraulic control system, comprising: the left oil pump is respectively communicated with the left front wheel hydraulic motor and the left rear wheel hydraulic motor through the left flow distributing and collecting valve so as to control the rotating speed and the rotating direction of a left front wheel and a left rear wheel; the right oil pump is respectively communicated with the right front wheel hydraulic motor and the right rear wheel hydraulic motor through the right flow distributing and collecting valve so as to control the rotating speed and the rotating direction of the right front wheel and the right rear wheel;
the brake system is characterized by further comprising an auxiliary oil pump, an energy accumulator and a brake valve, wherein the auxiliary oil pump is communicated with the brake valve, a damping valve and a one-way valve are arranged on an oil circuit connected with the auxiliary oil pump and the brake valve, the energy accumulator is connected to the oil circuit connected with the auxiliary oil pump and the brake valve, a throttle valve is further connected beside the position, located between the energy accumulator and the one-way valve, on the oil circuit, and the brake valve is used for braking the left front wheel, the left rear wheel, the right rear wheel and the right rear wheel;
the auxiliary oil pump is respectively connected with the left flow distributing and collecting valve and the right flow distributing and collecting valve through the pressure reducing overflow valve, and is also respectively connected with the left front wheel hydraulic motor, the left rear wheel hydraulic motor, the right front wheel hydraulic motor and the right rear wheel hydraulic motor through the pressure reducing overflow valve;
the parking device is characterized by further comprising a parking valve, wherein the parking valve is connected to an oil path between the energy accumulator and the brake valve, the parking valve is respectively connected with the left front wheel, the left rear wheel, the right front wheel and the right rear wheel, a valve front pressure sensor is connected to an oil inlet pipeline of the parking valve, and a valve rear pressure sensor is connected to an oil outlet pipeline of the parking valve;
the oil pump also comprises an electric proportional reversing valve or a pilot-operated plate-type electromagnetic overflow valve, wherein the electric proportional reversing valve or the pilot-operated plate-type electromagnetic overflow valve is communicated with an oil outlet pipeline of the auxiliary oil pump.
2. The four-wheel drive skid steer chassis hydraulic control system of claim 1, further comprising an overflow valve in parallel with the electro-proportional directional valve, the overflow valve being in communication with an oil outlet line of the auxiliary oil pump.
3. The four wheel drive skid steer chassis hydraulic control system of claim 2, wherein the spill valve communicates with a tank through a radiator and/or a bypass check valve.
4. A four wheel drive skid steer chassis hydraulic control system as recited in claim 1, wherein said left oil pump and said right oil pump are variable displacement plunger pumps.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111039205.7A CN113635966B (en) | 2021-09-06 | 2021-09-06 | Four-wheel drive slip steering chassis hydraulic control system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111039205.7A CN113635966B (en) | 2021-09-06 | 2021-09-06 | Four-wheel drive slip steering chassis hydraulic control system |
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| Publication Number | Publication Date |
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| CN113635966A CN113635966A (en) | 2021-11-12 |
| CN113635966B true CN113635966B (en) | 2023-04-14 |
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| CN202111039205.7A Active CN113635966B (en) | 2021-09-06 | 2021-09-06 | Four-wheel drive slip steering chassis hydraulic control system |
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| CN114738341B (en) * | 2022-04-22 | 2023-05-05 | 扬州市职业大学(扬州开放大学) | Walking hydraulic transmission system of hydraulic four-wheel drive high-clearance wheel type sprayer |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2005199835A (en) * | 2004-01-15 | 2005-07-28 | Kanzaki Kokyukoki Mfg Co Ltd | Steering wheel drive device, and four-wheel drive vehicle |
| CN201971601U (en) * | 2010-10-31 | 2011-09-14 | 合肥搬易通科技发展有限公司 | Three-wheel drive four-way static pressure forklift truck hydraulic system |
| CN201923203U (en) * | 2010-12-01 | 2011-08-10 | 泸州长起特种起重设备有限公司 | Hydraulic steering and brake circuit for two-bridge engineering machinery |
| CN102996562A (en) * | 2012-10-31 | 2013-03-27 | 玉柴桩工(常州)有限公司 | Multifunctional integrated valve set for winch motor |
| CN103359097A (en) * | 2013-07-18 | 2013-10-23 | 杭叉集团股份有限公司 | Hydraulic braking system of large-tonnage electric fork-lift truck |
| CN203372217U (en) * | 2013-07-18 | 2014-01-01 | 杭叉集团股份有限公司 | Large-tonnage electric forklift hydraulic braking system |
| CN105667477B (en) * | 2016-04-13 | 2018-01-23 | 武汉科技大学 | A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system |
| CN106740081A (en) * | 2016-12-16 | 2017-05-31 | 徐工消防安全装备有限公司 | A kind of aerial work platform four-wheel-driven control system |
| CN108506256A (en) * | 2018-03-27 | 2018-09-07 | 江苏恒立液压科技有限公司 | Drive hydraulic control system |
| CN208565100U (en) * | 2018-07-13 | 2019-03-01 | 湖南星邦重工有限公司 | A kind of hydraulic travel system |
| CN210715336U (en) * | 2019-08-29 | 2020-06-09 | 湘潭市恒欣实业有限公司 | Soft start hydrostatic driving system |
| CN110962924B (en) * | 2019-12-06 | 2021-04-06 | 湖南中联重科智能高空作业机械有限公司 | Hydraulic driving and steering system and aerial working machine |
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