Speed synchronization control method and system of road roller and road roller thereof

Abstract

The invention relates to a speed synchronization control method of a road roller, which comprises the following steps of: based on vehicle parameters of the road roller, establishing a relation between a displacement value of a front-drive driving pump and a displacement value of a rear-drive driving pump as a dependent variable and an independent variable; by controlling the displacement value of the front-drive running pump and the displacement value of the rear-drive running pump, the front-drive running pump and the rear-drive running pump are controlled to synchronously control the rotating speed of the front-drive motor and the rotating speed of the rear-drive motor; and according to the rotating speed of the front-drive motor and the rotating speed of the rear-drive motor, a road rolling wheel and a driving wheel reach the consistent target speed. The invention further discloses a control system for realizing the control method and the road roller with the driving system. Through the relation between the independent variable and the dependent variable, the displacement values of the front-drive traveling pump and the rear-drive traveling pump change along with the independent variable, so that the traveling speeds of the road rolling wheels and the traveling wheels can be accurately synchronized.

Description

Technical Field

[0001] The present invention relates to the field of speed control of a road roller, and more specifically, to a speed synchronization control method and system for a road roller and the road roller thereof. Background Art

[0002] A road roller, also known as a soil roller, is a kind of engineering machinery for road repair and belongs to the category of road equipment. The road roller uses the gravity of the machine itself and is suitable for various compaction operations, so that the rolled layer is permanently deformed and dense. It is widely used in filling and compaction operations of large-scale engineering projects such as high-grade highways, railways, airport runways, dams, and stadiums. It can roll sandy, semi-viscous and viscous soils, roadbed stabilized soils and asphalt concrete pavement layers. The structure of a road roller usually includes front drive components, rear drive components, frame assembly, electrical system assembly, cab assembly, center articulated frame assembly, etc. Among them, the front drive components include a front drive pump connected to the engine, a front drive motor connected to the front drive pump through a hydraulic hose, a reducer connected to the front drive motor, and a roller connected to the reducer. The roller is connected to the frame assembly and has a supporting and guiding function. The rear drive assembly includes a rear drive pump connected to the engine, a rear drive motor connected to the rear drive pump through a hydraulic hose, a rear axle connected to the rear drive motor, and a tire connected to the rear axle. The rear axle connects the driving wheels and the frame and has a supporting function. The driving wheels and roller wheels are only distinguished by name. The roller wheel itself is also a driving wheel. The roller wheel can also be called the front wheel and the driving wheel is called the rear wheel.

[0003] Road rollers are divided into two categories according to the roller wheels: steel wheel type and tire type. Regardless of whether they are steel wheel type or tire type, most of them adopt a single pump dual motor structure; (some rollers) adopt a dual pump dual motor structure, in which the front drive pump and front drive motor control the speed of the steel wheel to make it move and compact the road surface, and the rear drive pump and rear drive motor control the (tire) driving wheel to make it move. However, since one pump drives one motor, how to synchronize the speeds of the two is a difficult point in speed control of a dual pump dual motor road roller.

[0004] There are two methods for speed synchronization control of dual-pump dual-motor structure. One is to use a speed sensor to measure the front and rear wheel speeds, and then adjust the travel pump and motor displacement by the control unit to perform closed-loop control of speed matching. The other is to use the travel pump pressure signal as the control object, that is, pressure difference control. When the pressure difference between the two travel pumps exceeds the set value, the control unit adjusts the travel pump and motor displacement to match the front and rear wheel speeds, such as the driving system and control method of engineering vehicles recorded in Chinese patent document CN202210445081.0. In this scheme, when the front and rear wheel speeds are inconsistent, the travel hydraulic system causes the pressure to increase due to the pressure holding. When the pressure increases to a certain value (monitored by the pressure sensor), the front and rear wheel speeds are adjusted to make the front and rear wheel speeds close. However, the above two methods both adjust the speed after the speed difference occurs. The core is error correction. There is a time for detection and correction from the occurrence of speed difference to the correction of speed difference to synchronization, so true synchronization cannot be achieved. Summary of the invention

[0005] The present invention is to overcome the technical defect that the existing dual-pump dual-motor drive of a road roller is difficult to achieve synchronous control, and provides a speed synchronous control method for a road roller, which does not require the speed difference or pressure difference to be detected and then corrected. The present invention also provides a system and a road roller for implementing the synchronous control method.

[0006] In order to solve the above technical problems, the present invention provides a speed synchronization control method for a road roller, comprising:

[0007] Based on the vehicle parameters of the road roller, the relationship between the displacement value of the front drive pump and the displacement value of the rear drive pump as the dependent variable and the independent variable is established;

[0008] By controlling the displacement value of the front drive pump or the displacement value of the rear drive pump, the front drive pump or the rear drive pump is made to synchronously control the rotation speed of the front drive motor and the rotation speed of the rear drive motor;

[0009] According to the rotation speed of the front drive motor and the rotation speed of the rear drive motor, the roller wheel and the running wheel are controlled to reach a consistent target speed.

[0010] The specific steps of controlling the front drive pump or the rear drive pump to synchronously control the speed of the front drive motor and the speed of the rear drive motor by controlling the displacement value of the front drive pump or the displacement value of the rear drive pump are as follows:

[0011] Input the displacement value of the rear-wheel drive pump, and the displacement value of the front-wheel drive pump changes with the displacement value of the rear-wheel drive pump and obtains the calculated value;

[0012] The rotation speed of the rear drive motor and the rotation speed of the front drive motor are outputted according to the calculated values ​​of the displacement value of the rear drive pump and the displacement value of the front drive pump, respectively.

[0013] The specific steps of controlling the front drive pump or the rear drive pump to synchronously control the speed of the front drive motor and the speed of the rear drive motor by controlling the displacement value of the front drive pump or the displacement value of the rear drive pump may also be:

[0014] Input the displacement value of the front drive pump, and the displacement value of the rear drive pump changes with the displacement value of the front drive pump and obtains the calculated value;

[0015] The rotation speed of the rear drive motor and the rotation speed of the front drive motor are outputted according to the calculated values ​​of the displacement value of the front drive pump and the displacement value of the rear drive pump, respectively.

[0016] In the above technical solution, after establishing the relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as the dependent variable and the independent variable, let one of the front drive travel pump and the rear drive travel pump be the independent variable and the other be the dependent variable. The speed of the front drive motor and the speed of the rear drive motor of the roller are determined by the flow of the hydraulic system of the roller, and the flow of the hydraulic system is adjusted by the front drive travel pump and the rear drive travel pump. Therefore, the mapping relationship between the front drive travel pump and the rear drive travel pump is to make the front drive travel pump and the rear drive travel pump reach the corresponding displacement respectively, and the driving speed of the roller wheel and the driving wheel remain the same, so as to achieve precise synchronization of speed.

[0017] During driving, the driver often accelerates or decelerates to the target speed he wants to achieve. Taking the displacement value of the rear-wheel drive travel pump as an example, when accelerating or decelerating, the displacement value of the rear-wheel drive travel pump is input. Due to the independent variable and the dependent variable, once the displacement value of the rear-wheel drive travel pump changes, the displacement value of the front-wheel drive travel pump will also change accordingly. Reaching the target speed itself is a process of speed change. In this process, the displacement value of the rear-wheel drive travel pump and the displacement value of the front-wheel drive travel pump change synchronously, so the speed changes of the roller and the travel wheel are also synchronous, that is, the roller and the travel wheel can reach the target speed synchronously and both travel at the target speed. Conversely, the same principle applies to adjusting the front-wheel drive travel pump.

[0018] Based on the vehicle parameters of the road roller, a relationship is established in which the displacement value of the front drive travel pump and the rear drive travel pump are respectively the dependent variable and the independent variable, including: based on the vehicle parameters of the road roller, a relationship is established in which the displacement value of the rear drive travel pump is the independent variable and the displacement value of the front drive travel pump is the dependent variable, and the specific steps are:

[0019] Determine the total flow of the rear drive system according to the displacement value of the rear drive travel pump, the engine speed and the volumetric efficiency of the rear drive travel pump;

[0020] The speed of the rear drive motor is determined according to the total flow of the rear drive system, the volumetric efficiency of the rear drive motor and the displacement value of the rear drive motor;

[0021] The speed of the front drive motor is determined according to the speed of the rear drive motor, the radius of the roller wheel, the radius of the travel wheel, the reduction ratio of the reducer and the reduction ratio of the rear axle;

[0022] The speed of the driving wheel is determined according to the speed of the rear drive motor, the radius of the driving wheel, and the reduction ratio of the rear axle;

[0023] Let the speed of the driving wheel be equal to the speed of the roller wheel, and determine the speed of the front-drive motor according to the speed of the rear-drive motor, the radius of the roller wheel, the radius of the driving wheel, the reduction ratio of the reducer, and the reduction ratio of the rear axle;

[0024] The displacement value of the front drive pump is determined according to the front drive motor speed, the displacement value of the front drive motor, the volumetric efficiency of the front drive pump, the volumetric efficiency of the front drive motor and the engine speed, and then the displacement value of the rear drive pump is obtained as the independent variable and the displacement value of the front drive pump is the dependent variable.

[0025] The specific steps to establish the relationship are:

[0026] The total flow rate S of the rear drive system is determined according to the displacement value H of the rear drive pump, the engine speed M and the volumetric efficiency J of the rear drive pump, as follows:

[0027] S=H*M*J / 1000

[0028] Where, the displacement value of the rear drive pump is H, in cm 3 ; Engine speed M, unit is r / min; Volumetric efficiency J of rear-wheel drive pump, value is 0.85-0.99; Total flow rate S of rear-wheel drive system, unit is L / min.

[0029] The speed W of the rear-drive motor is determined according to the total flow S of the rear-drive system, the volumetric efficiency Q of the rear-drive motor, and the displacement value L of the rear-drive motor, as follows:

[0030] W=1000*S*Q / L

[0031] Where, the total flow rate of the rear drive system S is in L / min; the volumetric efficiency of the rear drive motor Q is 0.85-0.99; the displacement value of the rear drive motor L is in cm 3 ; The speed of the rear drive motor W, in r / min.

[0032] The speed V of the front drive motor is determined according to the speed W of the rear drive motor, the radius E of the roller wheel, the radius F of the travel wheel, the reduction ratio N of the reducer and the reduction ratio O of the rear axle, as follows:

[0033] V=W*F / E*N / O

[0034] In the formula, the speed of the rear drive motor W is in r / min; the radius of the roller wheel E is in m; the radius of the driving wheel F is in m; the reduction ratio N of the reducer is 60; the reduction ratio O of the rear axle is 40; the speed of the front drive motor V is in r / min.

[0035] The driving wheel speed Y is determined according to the rear drive motor speed W, the driving wheel radius F, and the rear axle reduction ratio O, as follows:

[0036] Y=W*2*3.1415926*F*60 / O / 1000

[0037] Wherein, the speed of the rear drive motor W, the unit is r / min; the radius of the driving wheel F, the unit is m; the reduction ratio of the rear axle O, the value is 40; the speed of the driving wheel Y, the unit is km / h.

[0038] To achieve speed synchronization, the speed of the traveling wheel must be equal to the speed of the roller, that is, Y=X, where X is the speed of the roller.

[0039] The roller speed X has the following relationship:

[0040] X=V*2*3.1415926*E*60 / 1000 / N

[0041] Wherein, V is the speed of the front drive motor, in r / min; N is the reduction ratio of the reducer, which is 60; E is the radius of the roller, in m; X is the roller speed, in km / h.

[0042] Wherein, V is the speed of the front drive motor, in r / min; N is the reduction ratio of the reducer, which is 60; E is the radius of the roller, in m; X is the roller speed, in km / h.

[0043] The speed V of the front drive motor is determined according to the speed W of the rear drive motor, the radius E of the roller wheel, the radius F of the travel wheel, the reduction ratio N of the reducer and the reduction ratio O of the rear axle, as follows:

[0044] V=W*F / E*N / O

[0045] In the formula, the speed of the rear drive motor W is in r / min; the radius of the roller wheel E is in m; the radius of the driving wheel F is in m; the reduction ratio N of the reducer is 60; the reduction ratio O of the rear axle is 40; the speed of the front drive motor V is in r / min.

[0046] The displacement value G of the front drive pump is determined according to the front drive motor speed V, the displacement value K of the front drive motor, the volumetric efficiency I of the front drive pump, the volumetric efficiency P of the front drive motor and the engine speed M, as follows:

[0047] G=K*V / M / I / P

[0048] Where, the speed of the front drive motor V is in r / min; the displacement of the front drive motor K is in cm 3 ; The volumetric efficiency of the front drive pump I is 0.95; the volumetric efficiency of the front drive motor P is 0.97; the engine speed M is in r / min; the displacement value of the front drive pump G is in cm 3 .

[0049] According to the above formula, the relationship between the displacement value of the front drive pump and the displacement value of the rear drive pump is obtained:

[0050] G=H*K / L*F / E*N / O*Q / P*J / I

[0051] Where G is the displacement of the front drive pump, in cm 3 ; K represents the displacement of the front drive motor, in cm 3 ; H represents the displacement value of the rear-wheel drive pump, in cm 3 ; J represents the volumetric efficiency of the rear-drive pump; Q represents the volumetric efficiency of the rear-drive motor; L represents the displacement value of the rear-drive motor, in cm 3 ; F represents the radius of the driving wheel, in m; E represents the radius of the roller wheel, in m; N represents the reduction ratio of the reducer; O represents the reduction ratio of the rear axle; I represents the volumetric efficiency of the front drive pump; P represents the volumetric efficiency of the front drive motor.

[0052] Preferably, the radius of the running wheel is determined according to the product of the specification size radius of the running wheel and the first correction coefficient; and / or the radius of the roller wheel is determined according to the product of the specification size radius of the roller wheel and the second correction coefficient. The first correction coefficient is a constant greater than 0 and less than or equal to 1. If the running wheel is a steel wheel, the first correction coefficient is 1. The second correction coefficient is a constant greater than 0 and less than or equal to 1. If the roller wheel is a steel wheel, the second correction coefficient is 1.

[0053] When the driving wheel and the roller are made of rubber, there will be compression, and the compression of the driving wheel and the roller may be different. Therefore, by setting the correction coefficient, the influence of the compression of the tire on the control accuracy can be eliminated.

[0054] Preferably, the displacement value of the front drive motor and the displacement value of the rear drive motor are both set to fixed values. During driving, the displacement value of the front drive motor and the displacement value of the rear drive motor will not change without human intervention, so that the mapping relationship between the front drive travel pump and the rear drive travel pump will not be affected by other parameters, ensuring its accuracy.

[0055] Preferably, a corresponding relationship between the displacement value of the front drive motor and the displacement value of the rear drive motor is set, and the displacement value of each front drive motor corresponds to the displacement value of a rear drive motor. If there are multiple fixed values ​​of the displacement value of the front drive motor, then the displacement value of each front drive motor will correspond to a fixed value of the displacement value of the rear drive motor, thereby forming different motor displacement combinations to adapt to different driving sections. When driving, the corresponding motor displacement combination can be selected according to the road section conditions and then the speed can be adjusted.

[0056] Preferably, the displacement values ​​of the front drive motor and the rear drive motor are set in four groups, each group corresponding to a driving gear of the roller. The displacement values ​​of the front drive motor and the rear drive motor corresponding to each driving gear are different. For example, in a lower gear, a larger motor displacement can be set to play a role in deceleration and torque increase, thereby improving the climbing ability of the vehicle; in a high gear, a smaller motor displacement can be set to increase the transfer speed.

[0057] A control system for implementing the above-mentioned speed synchronization control method for a road roller comprises:

[0058] a displacement value acquisition unit, used to acquire the displacement value of the front drive travel pump or the rear drive travel pump, the displacement value of the front drive motor, and the displacement value of the rear drive motor;

[0059] A data processing unit, used for establishing a relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as a dependent variable and an independent variable according to the vehicle parameters, and for calculating the displacement value of the corresponding rear drive travel pump or the front drive travel pump according to the relationship between the value acquired by the displacement value acquisition unit and the independent variable and the dependent variable;

[0060] The output unit is used to output the value calculated by the data processing unit to the rear-wheel drive travel pump or the front-wheel drive travel pump and make it reach the value.

[0061] An input unit is used to input vehicle parameters into the data processing unit. The input unit can input parameters other than the data that the displacement value acquisition unit can obtain into the data processing unit to ensure that the calculation of the data processing unit is accurate. In particular, there are situations where the roller and the driving wheel of the roller may be replaced.

[0062] In the above technical solution, the displacement value of the front drive travel pump or the rear drive travel pump is input, wherein the displacement value acquisition unit acquires the displacement value of the front drive travel pump or the rear drive travel pump in real time and transmits it to the data processing unit. At the same time, the displacement value acquisition unit also acquires the corresponding displacement values ​​of the front drive motor and the rear drive motor in the current state. After the data processing unit receives the displacement value of the front drive travel pump or the rear drive travel pump, the displacement value of the front drive motor and the displacement value of the rear drive motor, the data processing unit can calculate the corresponding value according to the vehicle parameters input by the input unit. If the displacement value acquisition unit acquires the displacement value of the front drive travel pump, the data processing unit outputs the displacement value of the rear drive travel pump. If the displacement value acquisition unit acquires the displacement value of the rear drive travel pump, the data processing unit outputs the displacement value of the front drive travel pump. After the data processing unit outputs the value in real time through the output unit, the displacement value of the corresponding rear drive travel pump or the front drive travel pump will change to the value in real time. While maintaining a fixed speed, the displacement value of the front drive pump and the displacement value of the rear drive pump will not change and conform to the mapping relationship. At this time, the driving speeds of the corresponding roller wheel and driving wheel are the same.

[0063] A road roller comprises a vehicle body, a travel handle, an engine, a front drive assembly and a rear drive assembly respectively connected to the engine, and the above-mentioned control system; the front drive assembly comprises a front drive travel pump connected to the engine, a front drive motor connected to the front drive travel pump, a reducer connected to the front drive motor, and a roller wheel connected to the reducer; the rear drive assembly comprises a rear drive travel pump connected to the engine, a rear drive motor connected to the rear drive travel pump, a rear axle connected to the rear drive motor, and a travel wheel connected to the rear axle, the travel handle is used to adjust the displacement value of the front drive travel pump or the rear drive travel pump; the displacement value acquisition unit is electrically connected to the front drive travel pump and / or the rear drive travel pump, and the output unit is electrically connected to the front drive travel pump and / or the rear drive travel pump

[0064] Preferably, a transfer case is further included, and the engine is connected to the front drive assembly and the rear drive assembly respectively through the transfer case.

[0065] Compared with the prior art, the beneficial effect of the present invention is: by establishing a relationship between the front-drive travel pump and the rear-drive travel pump as the dependent variable and the independent variable, the displacement value of the front-drive travel pump and the displacement value of the rear-drive travel pump can follow each other. Under this relationship, the travel speeds of the roller wheel and the travel wheel corresponding to the displacement value of the front-drive travel pump and the displacement value of the rear-drive travel pump can be the same, so that the travel speeds of the roller wheel and the travel wheel can be kept consistently and accurately synchronized without temporary speed asynchrony caused by the need to detect speed difference or pressure difference and then correct it. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 is a flow chart of a speed synchronization control method for a road roller of the present invention;

[0067] Figure 2 It is a framework diagram of a control system of a road roller of the present invention;

[0068] Figure 3 It is a connection frame diagram of a road roller of the present invention. DETAILED DESCRIPTION

[0069] The drawings are only for illustrative purposes and cannot be construed as limiting the present invention. To better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are only for illustrative purposes and cannot be construed as limiting the present invention.

[0070] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "long", "short" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, they are 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. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0071] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings:

[0072] Example 1

[0073] Embodiment 1 of a method for synchronously controlling the speed of a road roller, as Figure 1 As shown, including:

[0074] Based on the vehicle parameters of the roller, a relationship is established in which the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump are the dependent variable and the independent variable respectively; the vehicle parameters include the displacement value of the front drive travel pump, the displacement value of the front drive motor, the displacement value of the rear drive travel pump, the volumetric efficiency of the rear drive pump, the volumetric efficiency of the rear drive motor, the displacement value of the rear drive motor, the radius of the driving wheel, the radius of the roller wheel, the reduction ratio of the reducer, the reduction ratio of the rear axle, the volumetric efficiency of the front drive pump and the volumetric efficiency of the front drive motor.

[0075] The specific steps are:

[0076] The total flow rate S of the rear drive system is determined according to the displacement value H of the rear drive pump, the engine speed M and the volumetric efficiency J of the rear drive pump, as follows:

[0077] S=H*M*J / 1000

[0078] Where, the displacement value of the rear drive pump is H, in cm 3 ; Engine speed M, unit is r / min; Volumetric efficiency J of rear-drive travel pump, value is 0.85-0.99, value of this embodiment is 0.95; Total flow rate S of rear-drive system, unit is L / min.

[0079] The speed of the rear-drive motor is determined according to the total flow S of the rear-drive system, the volumetric efficiency Q of the rear-drive motor, and the displacement value L of the rear-drive motor, as follows:

[0080] W=1000*S*Q / L

[0081] Wherein, the total flow rate S of the rear drive system is in L / min; the volumetric efficiency Q of the rear drive motor is in the range of 0.85-0.99, and the value of this embodiment is 0.97; the displacement value L of the rear drive motor is in cm 3 ; The speed of the rear drive motor W, in r / min.

[0082] The speed V of the front drive motor is determined according to the speed W of the rear drive motor, the radius E of the roller wheel, the radius F of the travel wheel, the reduction ratio N of the reducer and the reduction ratio O of the rear axle, as follows:

[0083] V=W*F / E*N / O

[0084] In the formula, the speed of the rear drive motor W is in r / min; the radius of the roller wheel E is in m; the radius of the driving wheel F is in m; the reduction ratio N of the reducer is 60; the reduction ratio O of the rear axle is 40; the speed of the front drive motor V is in r / min.

[0085] The driving wheel speed Y is determined according to the rear drive motor speed W, the driving wheel radius F, and the rear axle reduction ratio O, as follows:

[0086] Y=W*2*3.1415926*F*60 / O / 1000

[0087] Wherein, the speed of the rear drive motor W, the unit is r / min; the radius of the driving wheel F, the unit is m; the reduction ratio of the rear axle O, the value is 40; the driving wheel speed Y, the unit is km / h.

[0088] To achieve speed synchronization, the speed of the traveling wheel must be equal to the speed of the roller, that is, Y=X, where X is the speed of the roller.

[0089] The roller speed X has the following relationship:

[0090] X=V*2*3.1415926*E*60 / 1000 / N

[0091] Wherein, V is the speed of the front drive motor, in r / min; N is the reduction ratio of the reducer, which is 60; E is the radius of the roller, in m; X is the roller speed, in km / h.

[0092] Wherein, V is the speed of the front drive motor, in r / min; N is the reduction ratio of the reducer, which is 60; E is the radius of the roller, in m; X is the roller speed, in km / h.

[0093] The speed V of the front drive motor is determined according to the speed W of the rear drive motor, the radius E of the roller wheel, the radius F of the travel wheel, the reduction ratio N of the reducer and the reduction ratio O of the rear axle, as follows:

[0094] V=W*F / E*N / O

[0095] In the formula, the speed of the rear drive motor W is in r / min; the radius of the roller wheel E is in m; the radius of the driving wheel F is in m; the reduction ratio N of the reducer is 60; the reduction ratio O of the rear axle is 40; the speed of the front drive motor V is in r / min.

[0096] The displacement value G of the front drive pump is determined according to the front drive motor speed V, the displacement value K of the front drive motor, the volumetric efficiency I of the front drive pump, the volumetric efficiency P of the front drive motor and the engine speed M, as follows:

[0097] G=K*V / M / I / P

[0098] According to the above formula, the relationship between the displacement value of the front drive pump and the displacement value of the rear drive pump is obtained:

[0099] G=H*K / L*F / E*N / O*Q / P*J / I

[0100] Where G is the displacement of the front drive pump, in cm 3 ; K represents the displacement of the front drive motor, in cm 3 ; H represents the displacement value of the rear-wheel drive pump, in cm 3 ; J represents the volumetric efficiency of the rear-drive pump; Q represents the volumetric efficiency of the rear-drive motor; L represents the displacement value of the rear-drive motor, in cm 3; F represents the radius of the driving wheel, in m; E represents the radius of the roller wheel, in m, and the roller wheel is a steel wheel or a tire; N represents the reduction ratio of the reducer; O represents the reduction ratio of the rear axle; I represents the volumetric efficiency of the front drive pump; P represents the volumetric efficiency of the front drive motor; Y is the driving wheel speed; X is the roller wheel speed; M is the engine speed. Among them, the volumetric efficiency of the front drive pump and the rear drive pump is the same, generally 0.95. The volumetric efficiency of the front drive motor or the rear drive motor is the same, generally 0.97.

[0101] Input the displacement value of the rear-wheel drive pump, and the displacement value of the front-wheel drive pump changes with the displacement value of the rear-wheel drive pump and obtains the calculated value;

[0102] The rotation speed of the rear drive motor and the rotation speed of the front drive motor are outputted according to the calculated values ​​of the input displacement value of the rear drive pump and the displacement value of the front drive pump, respectively.

[0103] According to the rotation speed of the front drive motor and the rotation speed of the rear drive motor, the roller wheel and the running wheel are made to reach a consistent target speed.

[0104] In this embodiment, the displacement value of the conventional rear-wheel drive travel pump is used as the input value, that is, by inputting the displacement value of the rear-wheel drive travel pump, the displacement value of the front-wheel drive travel pump is changed according to the mapping relationship along with the displacement value of the rear-wheel drive travel pump to obtain a calculated value.

[0105] The radius of the driving wheel is determined according to the product of the specification size radius of the driving wheel and the first correction coefficient; and / or the radius of the roller wheel is determined according to the product of the specification size radius of the roller wheel and the second correction coefficient. In this embodiment, the radius of the driving wheel and the radius of the roller wheel are specifically:

[0106] F=R1*U1

[0107] E=R2*U2

[0108] In the formula, R1 is the radius corresponding to the specification size of the driving wheel; U1 is the first correction coefficient. If the driving wheel is a steel wheel, the first correction coefficient is 1; R2 is the radius corresponding to the specification size of the roller wheel; U2 is the second correction coefficient. If the roller wheel is a steel wheel, the correction coefficient is 1.

[0109] When the driving wheel and the roller are made of rubber, there will be compression, and the compression of the driving wheel and the roller may be different. Therefore, by setting the first correction coefficient and the second correction coefficient, the influence of the compression of the driving wheel and the roller on the control accuracy is eliminated. If the driving wheel and the roller are made of rubber, the first correction coefficient and the second correction coefficient can be set to 0.95-0.98. In this embodiment, they are specifically set to 0.97.

[0110] The working principle or working process of this embodiment is as follows: after establishing the relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as the dependent variable and the independent variable, let one of the front drive travel pump and the rear drive travel pump be the independent variable and the other be the dependent variable. The speed of the front drive motor and the rear drive motor of the roller is determined by the hydraulic system of the roller, and the flow of the hydraulic system is adjusted by the front drive travel pump and the rear drive travel pump. Therefore, the displacement value of the front drive travel pump and the rear drive travel pump is the relationship between the dependent variable and the independent variable. When the front drive travel pump and the rear drive travel pump each reach the corresponding displacement, the driving speed of the roller wheel and the driving wheel remains the same, thereby achieving precise synchronization of speed.

[0111] During driving, the driver often accelerates or decelerates to the target speed he wants to achieve. In this embodiment, the displacement value of the rear-drive driving pump is input. When accelerating or decelerating, the displacement value of the rear-drive driving pump is adjusted to achieve the input. Once the displacement value of the rear-drive driving pump changes, the displacement value of the front-drive driving pump will also change accordingly. Reaching the target speed itself is a process of speed change. In this process, the displacement value of the rear-drive driving pump and the displacement value of the front-drive driving pump change synchronously. Therefore, the speed change of the roller and the driving wheel is also synchronous, that is, the roller and the driving wheel can reach the target speed synchronously and both drive at the target speed. Conversely, adjusting the front-drive driving pump is also based on the same principle. The following table is a speed comparison table of the roller and the driving wheel after adopting the control method of this embodiment (data retains two decimal places).

[0112]

[0113]

[0114] It can be seen from the above table that after the displacement value of the travel pump is input, the displacement value of the front drive travel pump changes accordingly, and finally the speed of the roller wheel is made consistent with the speed of the travel wheel.

[0115] The beneficial effects of this embodiment are as follows: by establishing the relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as the dependent variable and the independent variable, the displacement values ​​of the front drive travel pump and the rear drive travel pump can follow each other's changes. Under this relationship, the driving speeds of the roller wheel and the driving wheel corresponding to the displacement values ​​of the front drive travel pump and the rear drive travel pump can be the same, so that the driving speeds of the roller wheel and the driving wheel can be kept consistently and accurately synchronized without temporary speed asynchrony caused by the need to detect speed difference or pressure difference and then correct it.

[0116] Example 2

[0117] Embodiment 2 of a method for synchronous speed control of a road roller differs from Embodiment 1 in that:

[0118] The front drive pump is the independent variable, and the rear drive pump is the dependent variable.

[0119] Input the displacement value of the front drive pump, and the displacement value of the rear drive pump changes with the displacement value of the front drive pump and obtains the calculated value;

[0120] The rotation speed of the rear drive motor and the rotation speed of the front drive motor are outputted based on the calculated values ​​of the input displacement value of the front drive pump and the displacement value of the rear drive pump, respectively.

[0121] The specific steps to establish the relationship between the displacement value of the front drive pump and the rear drive pump as the independent variable and the dependent variable are:

[0122] The total flow of the front drive system is determined according to the displacement value G of the front drive pump, the engine speed M and the volumetric efficiency I of the front drive pump, as follows:

[0123] R=G*M*I / 1000

[0124] The speed V of the front-wheel drive motor is determined according to the total flow R of the front-wheel drive system, the volumetric efficiency P of the front-wheel drive motor and the displacement value K of the front-wheel drive motor, as follows:

[0125] V=1000*R*P / K

[0126] The roller speed X is determined according to the front drive motor speed V, roller radius E, and reducer ratio N, as follows:

[0127] X=V*2*3.1415926*E*60 / N / 1000

[0128] To achieve speed synchronization, the speed of the driving wheel must be equal to the speed of the roller, that is, Y = X; Y is the speed of the driving wheel

[0129] Y=V*2*3.1415926*F*60 / 1000 / O

[0130] The speed W of the rear drive motor is determined according to the speed V of the front drive motor, the radius E of the roller wheel, the radius F of the travel wheel, the reduction ratio N of the reducer and the reduction ratio O of the rear axle, as follows:

[0131] W=V*E / F*O / N

[0132] The displacement value H of the rear drive pump is determined according to the rear drive motor speed W, the displacement value L of the rear drive motor, the volumetric efficiency J of the rear drive pump, the volumetric efficiency Q of the rear drive motor and the engine speed M, as follows:

[0133] H=L*W / M / J / Q

[0134] According to the above formula, the relationship between the displacement value of the rear-drive travel pump and the displacement value of the front-drive travel pump is obtained:

[0135] H=G*L / K*E / F*O / N*P / Q*I / J

[0136] Where G is the displacement of the front drive pump, in cm 3 ; K represents the displacement of the front drive motor, in cm 3 ; H represents the displacement value of the rear-wheel drive pump, in cm 3 ; J represents the volumetric efficiency of the rear-drive pump; Q represents the volumetric efficiency of the rear-drive motor; L represents the displacement value of the rear-drive motor, in cm 3 ; F represents the radius of the driving wheel, in m; E represents the radius of the roller wheel, in m, and the roller wheel is a steel wheel or a tire; N represents the reduction ratio of the reducer; O represents the reduction ratio of the rear axle; I represents the volumetric efficiency of the front drive pump; P represents the volumetric efficiency of the front drive motor; Y represents the driving wheel speed; X represents the roller wheel speed.

[0137] The remaining features and working principles of this embodiment are consistent with those of Embodiment 1.

[0138] Example 3

[0139] Embodiment 3 of a speed synchronization control method for a road roller differs from Embodiment 1 or 2 in that the displacement value of the front drive motor and the displacement value of the rear drive motor are both set to fixed values ​​and the displacement value of the front drive motor and the displacement value of the rear drive motor have a corresponding relationship, and the displacement value of each front drive motor corresponds to the displacement value of a rear drive motor respectively.

[0140] In this embodiment, there are four displacement values ​​of the front drive motor and the rear drive motor. According to the corresponding relationship, there are four groups of displacement values ​​of the front drive motor and the rear drive motor. Each group corresponds to a driving gear of the roller. The displacement values ​​of the front drive motor and the rear drive motor corresponding to each driving gear are different. For example, in a lower gear, a larger motor displacement can be set to reduce speed and increase torque, thereby improving the climbing ability of the vehicle. In a high gear, a smaller motor displacement can be set to increase the transition speed. The four groups of gears are specifically shown in the following table:

[0141] Gear Front drive motor displacement Rear drive motor displacement Ⅰ 55 110 Ⅱ 45 100 Ⅲ 35 90 Ⅳ 30 70

[0142] The working principle and beneficial effects of this embodiment: when the driver wants the roller to reach the target speed, he should select the corresponding driving gear according to the current road conditions before adjusting the displacement value of the rear-wheel drive pump. After selecting the driving gear, the displacement value of the front-wheel drive motor and the displacement value of the rear-wheel drive motor will be fixed to a fixed value, and the fixed value will not change unless the driver changes the driving gear again during driving, so that the mapping relationship between the front-wheel drive pump and the rear-wheel drive pump will not be affected by other parameters, thereby ensuring its accuracy.

[0143] The remaining features and working principles of this embodiment are consistent with those of Embodiment 1.

[0144] Example 4

[0145] A control system for a road roller, used to implement a speed synchronization control method for a road roller of embodiments 1-3, such as Figure 2 As shown, including:

[0146] a displacement value acquisition unit, used to acquire the displacement value of the front drive travel pump or the rear drive travel pump, the displacement value of the front drive motor, and the displacement value of the rear drive motor;

[0147] A data processing unit, used for establishing a relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as a dependent variable and an independent variable according to the vehicle parameters, and for calculating the displacement value of the corresponding rear drive travel pump or the front drive travel pump according to the relationship between the value acquired by the displacement value acquisition unit and the independent variable and the dependent variable;

[0148] The output unit is used to output the value calculated by the data processing unit to the rear-wheel drive travel pump or the front-wheel drive travel pump and make it reach the value.

[0149] The input unit is used to input vehicle parameters into the data processing unit. The input unit can input parameters other than the data that the displacement value acquisition unit can obtain into the data processing unit to ensure the accuracy of the calculation of the data processing unit. In particular, there are situations where the roller and the driving wheel of the roller may be replaced.

[0150] In other embodiments, the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as dependent variables and independent variables can be directly stored in the data processing unit, wherein the data processing unit can only store the displacement value of the front drive travel pump as the calculated value of the relationship G=H*K / L*F / E*N / O*Q / P*J / I, or only store the displacement value of the rear drive travel pump as the calculated value, and the data processing unit stores the relationship H=G*L / K*E / F*O / N*P / Q*I / J.

[0151] Of course, the data processing unit can also store the above relationship at the same time, and when the roller is used, it can be selected and set according to the situation of the roller.

[0152] The working process or working principle of this embodiment: Taking the implementation of embodiment 1 as an example, the displacement value of the rear-drive travel pump is input, wherein the displacement value acquisition unit acquires the displacement value of the rear-drive travel pump in real time and transmits it to the data processing unit, and the displacement value acquisition unit also acquires the corresponding displacement values ​​of the front-drive motor and the rear-drive motor in the current state. After the data processing unit receives the displacement value of the rear-drive travel pump, the displacement value of the front-drive motor and the displacement value of the rear-drive motor, and at the same time, according to the vehicle parameters input by the input unit and the relationship between the independent variable and the dependent variable is established, the data processing unit can calculate the displacement value of the corresponding front-drive travel pump. After the data processing unit outputs the value in real time through the output unit, the displacement value of the corresponding front-drive travel pump will change to the value in real time. In the case of maintaining a fixed speed, the displacement value of the front-drive travel pump and the displacement value of the rear-drive travel pump will not change and conform to the mapping relationship. At this time, the driving speed of the corresponding roller wheel and the driving wheel is consistent.

[0153] Beneficial effects of this embodiment: Through the driving system of this embodiment, the displacement value data of the rear-drive driving pump is obtained in real time, and the displacement value of the front-drive driving pump is calculated and adjusted according to the relationship between the displacement values ​​of the front-drive driving pump and the displacement value of the rear-drive driving pump, so that the displacement value of the front-drive driving pump follows the displacement value change of the rear-drive driving pump in real time, and when the relationship between the two can make the driving speeds of the roller wheel and the driving wheel corresponding to the displacement values ​​of the front-drive driving pump and the rear-drive driving pump the same, the driving speeds of the roller wheel and the driving wheel can be kept consistent and precisely synchronized. The driving system does not need to detect the speed difference or pressure difference, and then make corrections through numerical comparison and judgment. Not only will there be temporary speed asynchronism due to the existence of speed difference and detection and correction, but also the data processing volume can be reduced to reduce the pressure of the controller processing data and the hydraulic system has no pressure holding phenomenon, and the service life of hydraulic components and mechanical originals is longer.

[0154] Example 5

[0155] An embodiment of a road roller, such as Figure 3 As shown, it includes a vehicle body, a driving handle installed on the vehicle body, an engine 1, a front drive assembly connected to the engine 1, a rear drive assembly and a control system of embodiment 3. The front drive assembly includes a front drive pump 2 connected to the engine 1, a front drive motor 3 connected to the front drive pump 2, a reducer 4 connected to the front drive motor 3 and a roller 5 connected to the reducer 4; the rear drive assembly includes a rear drive pump 6 connected to the engine 1, a rear drive motor 7 connected to the rear drive pump 6, a rear axle 8 connected to the rear drive motor 7 and a driving wheel 9 connected to the rear axle 8, and the driving handle is used to adjust the displacement value of the rear drive pump 6. The displacement value acquisition unit is electrically connected to the front drive pump and the rear drive pump, and the output unit is electrically connected to the front drive pump and the rear drive pump.

[0156] Furthermore, a transfer case 10 is included, and the engine 1 is connected to the front drive assembly and the rear drive assembly respectively through the transfer case 10.

[0157] The displacement value of the rear drive travel pump 6 is adjusted by operating the travel handle, so as to input the displacement value of the rear drive travel pump 6, and the displacement value acquisition unit acquires the input displacement value of the rear drive travel pump and the corresponding displacement values ​​of the front drive motor and the rear drive motor in the current state. The data processing unit calculates the displacement value of the front drive travel pump 2 according to the data acquired by the displacement value acquisition unit, the vehicle parameters and the established relationship. The output unit outputs the calculated displacement value of the front drive travel pump 2 to the front drive travel pump and makes it reach the value. The rear drive travel pump 6 controls the speed of the rear drive motor 7 with its input displacement value and makes the travel wheel 9 reach the target speed, and the front drive travel pump 2 controls the speed of the front drive motor 3 with its changed calculated value and makes the roller wheel 5 also reach the target speed.

[0158] The speeds of the roller wheel and the traveling wheel of the roller are consistent with each other and are kept synchronous, so as to avoid the phenomenon that the roller wheel or the traveling wheel is pushed or pulled due to the speed asynchrony of the roller.

[0159] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A speed synchronization control method for a road roller, characterized in that: include: Based on the vehicle parameters of the road roller, the relationship between the displacement value of the front drive pump and the displacement value of the rear drive pump as the independent variable and the dependent variable is established; By controlling the displacement value of the front drive pump or the displacement value of the rear drive pump, the front drive pump or the rear drive pump is made to synchronously control the rotation speed of the front drive motor and the rotation speed of the rear drive motor; According to the rotation speed of the front drive motor and the rotation speed of the rear drive motor, the roller wheel and the running wheel are controlled to reach a consistent target speed.

2. The speed synchronization control method for a road roller according to claim 1, characterized in that: The specific steps of controlling the displacement value of the front drive pump or the rear drive pump so that the front drive pump or the rear drive pump synchronously controls the rotation speed of the front drive motor and the rotation speed of the rear drive motor are as follows: Input the displacement value of the rear-wheel drive pump, and the displacement value of the front-wheel drive pump changes with the displacement value of the rear-wheel drive pump and obtains the calculated value; outputting the rotation speed of the rear drive motor and the rotation speed of the front drive motor respectively according to the calculated values ​​of the displacement value of the rear drive pump and the displacement value of the front drive pump; or, Input the displacement value of the front drive pump, and the displacement value of the rear drive pump changes with the displacement value of the front drive pump and obtains the calculated value; The rotation speed of the front drive motor and the rotation speed of the rear drive motor are outputted according to the calculated values ​​of the displacement value of the front drive pump and the displacement value of the rear drive pump, respectively.

3. The speed synchronization control method for a road roller according to claim 1, characterized in that: The method of establishing the relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as the dependent variable and the independent variable based on the vehicle parameters of the road roller comprises: establishing the relationship between the displacement value of the rear drive travel pump and the displacement value of the front drive travel pump as the independent variable and the displacement value of the front drive travel pump as the dependent variable based on the vehicle parameters of the road roller, and the specific steps are as follows: Determine the total flow of the rear drive system according to the displacement value of the rear drive travel pump, the engine speed and the volumetric efficiency of the rear drive travel pump; The speed of the rear drive motor is determined according to the total flow of the rear drive system, the volumetric efficiency of the rear drive motor and the displacement value of the rear drive motor; The speed of the front drive motor is determined according to the speed of the rear drive motor, the radius of the roller wheel, the radius of the travel wheel, the reduction ratio of the reducer and the reduction ratio of the rear axle; The speed of the driving wheel is determined according to the speed of the rear drive motor, the radius of the driving wheel, and the reduction ratio of the rear axle; Let the speed of the driving wheel be equal to the speed of the roller wheel, and determine the speed of the front-drive motor according to the speed of the rear-drive motor, the radius of the roller wheel, the radius of the driving wheel, the reduction ratio of the reducer, and the reduction ratio of the rear axle; The displacement value of the front drive pump is determined according to the front drive motor speed, the displacement value of the front drive motor, the volumetric efficiency of the front drive pump, the volumetric efficiency of the front drive motor and the engine speed, and then the displacement value of the rear drive pump is obtained as the independent variable and the displacement value of the front drive pump is the dependent variable.

4. The speed synchronization control method for a road roller according to claim 3, characterized in that: The radius of the running wheel is determined according to the product of the specification size radius of the running wheel and the first correction coefficient; and / or the radius of the roller wheel is determined according to the product of the specification size radius of the roller wheel and the second correction coefficient.

5. A speed synchronization control method for a road roller according to any one of claims 1 to 4, characterized in that: The displacement value of the front drive motor and the displacement value of the rear drive motor are both set to fixed values.

6. The speed synchronization control method for a road roller according to claim 5, characterized in that: A corresponding relationship between the displacement values ​​of the front drive motor and the displacement values ​​of the rear drive motor is set, and the displacement value of each front drive motor corresponds to the displacement value of one rear drive motor.

7. The speed synchronization control method for a road roller according to claim 6, characterized in that: There are four groups of displacement values ​​of the front drive motor and the rear drive motor, and each group corresponds to a driving gear position of the roller.

8. A control system for implementing the speed synchronization control method for a road roller according to any one of claims 1 to 7, characterized in that: include: a displacement value acquisition unit, used to acquire the displacement value of the front drive travel pump or the rear drive travel pump, the displacement value of the front drive motor, and the displacement value of the rear drive motor; A data processing unit, used for establishing a relationship between the displacement value of the front drive travel pump and the displacement value of the rear drive travel pump as a dependent variable and an independent variable according to the vehicle parameters, and for calculating the displacement value of the corresponding rear drive travel pump or the front drive travel pump according to the relationship between the value acquired by the displacement value acquisition unit and the independent variable and the dependent variable; An output unit, used for outputting the value calculated by the data processing unit to a rear-wheel drive travel pump or a front-wheel drive travel pump and making it reach the value; The input unit is used to input vehicle parameters into the data processing unit.

9. A road roller, comprising a vehicle body, a travel handle mounted on the vehicle body, an engine (1), a front drive assembly and a rear drive assembly respectively connected to the engine (1); the front drive assembly comprises a front drive pump (2) connected to the engine (1), a front drive motor (3) connected to the front drive pump (2), a reducer (4) connected to the front drive motor (3), and a roller (5) connected to the reducer (4); the rear drive assembly comprises a rear drive pump (6) connected to the engine (1), a rear drive motor (7) connected to the rear drive pump (6), a rear axle (8) connected to the rear drive motor (7), and a travel wheel (9) connected to the rear axle (8); the travel handle is used to adjust the displacement value of the front drive pump (2) or the rear drive pump (2), and is characterized in that: The control system according to claim 8 is installed on the vehicle body; the displacement value acquisition unit is electrically connected to the front drive pump and / or the rear drive pump, and the output unit is electrically connected to the front drive pump and / or the rear drive pump.

10. The road roller of claim 9, further comprising a transfer case (10), wherein the engine (1) is connected to the front drive assembly and the rear drive assembly respectively via the transfer case (10).

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