CN203460698U - Front-wheel auxiliary drive system for land leveler - Google Patents

Front-wheel auxiliary drive system for land leveler Download PDF

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Publication number
CN203460698U
CN203460698U CN201320457546.0U CN201320457546U CN203460698U CN 203460698 U CN203460698 U CN 203460698U CN 201320457546 U CN201320457546 U CN 201320457546U CN 203460698 U CN203460698 U CN 203460698U
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China
Prior art keywords
wheel
valve
drive
motor
hydraulic
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Withdrawn - After Issue
Application number
CN201320457546.0U
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Chinese (zh)
Inventor
苗国华
刘永坚
冯克祥
杨久虎
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Shandong Lingong Construction Machinery Co Ltd
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Shandong Lingong Construction Machinery Co Ltd
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Abstract

The utility model discloses a front-wheel auxiliary drive system for a land leveler and belongs to the field of engineering machinery. By means of the system, the problems that the certain side driving force can be lost easily, straight driving is difficult to maintain, steering differential control is difficult to achieve and the like during prior single-pump double-motor front-wheel auxiliary driving are solved. According to the technical scheme, the system comprises a motor, a gearbox, an auxiliary drive hydraulic system and a hydraulic control system. The auxiliary drive hydraulic system comprises an integrated pressure cut-off valve, a load sensing valve, a variable pump, a hydraulic valve, a solenoid directional valve, a left motor, a right motor, a shuttle valve and a throttle valve and further comprises an electro-hydraulic proportional directional valve and a split-flow valve. The hydraulic control system comprises a drive mode selection switch and a front-wheel auxiliary drive speed knob. The system is mainly used on the land leveler, and front-wheel auxiliary all-wheel drive capable of increasing traction of the land leveler and front-wheel independent drive capable of preventing damage of rear-wheel drive to the road surface evenness during fine leveling can be achieved.

Description

Road grader front-wheel assistant drive system
Technical field
The utility model relates to a kind of Construction Machinery System, specifically, relates in particular to a kind of road grader front-wheel assistant drive system.
Background technology
Road grader is typical towed Work machine, and equipment promotes by the tractive force of machine walking, and in the prior art, most of road grader adopts back axle wheel to drive, and propons only possesses turning function and do not drive tractive force.So road grader tractive force limit only determined by back axle wheel load and adhesion value, because load per axle before road grader generally accounts for 30% left and right of complete machine weight, so road grader has 30% left and right tractive force not brought into play.And when the meticulous smooth working condition of road grader, road pavement planeness is had relatively high expectations, common back-wheel drive may be excessive and on smooth-riding surface, forming rut due to back-wheel drive moment when meticulous smooth operation, road pavement planeness causes damage, front-wheel individual drive pattern is avoided the generation of this kind of phenomenon, and under front-wheel individual drive pattern, trailing wheel is neutral gear position, complete machine is towed by front-wheel, and damage is caused on the road surface that trailing wheel can the smooth mistake of road pavement.
For meeting road grader operating needs under different operating modes, front-wheel assistive drive can realize full wheel drive pattern and front-wheel individual drive pattern addresses the above problem.For front-wheel assistant drive system and control thereof, in prior art form, a kind of employing double pump+double motor type of drive, when double pump+double motor scheme can solve in some cases left and right front-wheel load and do not wait (as slope operation time) thus can cause left and right motor rotary speed not wait is difficult to guarantee road grader straight-line travelling problem, and different flow and the pressure demand of front-wheel about can control two capacity of pump and meet turning by adjusting time, but while turning for realizing wheel, double pump different displacements is controlled, need to increase front-wheel steering angle sensor and articulation steering angular transducer, relatively single pump double motor type of drive of while, increase a driving pump, so cost is relatively high and control more complicated.The second adopts single pump double motor scheme, as shown in Figure 1, because motor adopts parallel way, when not waiting, can cause left and right front-wheel load the left and right motor rotary speed very difficult assurance road grader straight-line travelling problem such as not, simultaneously poor at certain side front vehicle wheel adhesion value, while occurring skidding, easily cause the side motor assignment of traffic of skidding too much to exceed the speed limit, and other single wheel is without driving, cause the forfeiture that drives tractive force, and when turning to, turn to inboard wheel rotating speed low, resistance wheel is larger, and turn to outboard wheels rotating speed fast, resistance wheel is less, required flow is different, because left and right motor is in parallel.Left and right motor pressure is identical, cause while turning about the more difficult differential of realizing of front-wheel.
Utility model content
The utility model object is to provide a kind of road grader front-wheel assistant drive system, to overcome the defect that in prior art, road grader front-wheel assistant drive system exists.
The utility model is achieved through the following technical solutions: a kind of road grader front-wheel assistant drive system comprises driving engine, change speed gear box, assistive drive hydraulic efficiency pressure system and hydraulic control system, described assistive drive hydraulic efficiency pressure system comprises the integrated pressure shutoff valve that oil circuit communicates, load-sensing valve, controllable capacity pump, reducing valve, solenoid directional control valve, left, right motor, shuttle valve, flow regulating valve, described integrated pressure shutoff valve is connected with driving engine by jackshaft with the controllable capacity pump of load-sensing valve, a left side, right motor is left with road grader respectively, off front wheel connects, and this hydraulic efficiency pressure system also comprises electro-hydraulic proportion reversing valve and flow divider valve, a left side, the A of right motor, B mouth directly communicates with fuel tank by two check valves of flow divider valve and the meta of electro-hydraulic proportion reversing valve, and described hydraulic control system comprises drive pattern select switch, front-wheel assistive drive speed knob, can adjust the control electric current of electro-hydraulic proportion reversing valve, the adjusting of speed while realizing front-wheel individual drive by front-wheel assistive drive speed knob.
This hydraulic efficiency pressure system also comprises electromagnetic proportion relief valve, and described hydraulic control system also comprises the front-wheel assistive drive tractive force knob that drives tractive force to regulate in the time of can realizing front-wheel individual drive.
Left and right motor is Double-discharge radial plunger piston motor.
Compared with prior art, the beneficial effects of the utility model are:
(1) according to front-wheel assistive drive of the present utility model and control system thereof, road grader can be realized respectively the full wheel drive pattern of back-wheel drive pattern, front-wheel assistive drive and three kinds of patterns of front-wheel individual drive according to operating mode, improve operating efficiency, in the full wheel drive pattern of front-wheel assistive drive, effectively improve road grader tractive force, expanded the range of use of road grader, in front-wheel individual drive pattern, be conducive to meticulous smooth operation, reduce the damage of road pavement planeness.
(2) compare existing double pump+double motor assistive drive, front-wheel auxiliary driving structure of the present utility model is simple, cost is lower, it is relatively simple to control.
(3) compare existing single pump double motor front-wheel assistive drive, front-wheel assistive drive described in this patent has solved can cause the left and right motor rotary speed very difficult assurance road grader straight-line travelling problem such as not when current existing single pump double motor does not wait due to left and right front-wheel load, at certain, side front vehicle wheel adhesion value is poor while occurring skidding, easily cause the side motor assignment of traffic of skidding too much to exceed the speed limit, and single wheel, without driving, causes the more difficult problems such as differential that realize of left and right front-wheel when driving the forfeiture of tractive force and turning in addition.
Accompanying drawing explanation
Fig. 1 is the front-wheel assistive drive schematic diagram of prior art list pump double motor scheme;
Fig. 2 is front-wheel assistive drive schematic diagram of the present utility model;
Fig. 3 is the I portion enlarged drawing of Fig. 2;
Fig. 4 is that the utility model front-wheel assistive drive realizes back-wheel drive pattern, full wheel drive pattern and front-wheel individual drive pattern diagram.
In figure, 1, controllable capacity pump; 2, servo plunger case; 3, pressure shut-off valve; 4, load-sensing valve; 5, electro-hydraulic reversing valve; 6, shuttle valve; 7, Double-discharge radial plunger piston motor; 8, electromagnetic valve change-over valve; 9, flow regulating valve; 10, reducing valve controllable capacity pump; 110, controllable capacity pump; 111, servo plunger case; 112, pressure shut-off valve; 113, load-sensing valve; 114, electromagnetic proportion relief valve; 115, reducing valve; 116, solenoid directional control valve; 117, flow divider valve; 118, left Double-discharge radial plunger piston motor; 119, right Double-discharge radial plunger piston motor; 120, flow regulating valve; 121, shuttle valve; 122, electro-hydraulic proportion reversing valve; 123, back-wheel drive pattern; 124, drive pattern select switch; 125, the full wheel drive pattern of front-wheel assistive drive; 126, front-wheel individual drive pattern; 127, front-wheel assistive drive speed knob; 128, front-wheel assistive drive tractive force knob.
The specific embodiment
Below in conjunction with accompanying drawing, the utility model will be further described:
As shown in Figure 1, in prior art, single pump double motor scheme is because motor adopts parallel way, when not waiting, can cause left and right front-wheel load the left and right motor rotary speed very difficult assurance road grader straight-line travelling problem such as not, simultaneously poor at certain side front vehicle wheel adhesion value, while occurring skidding, easily cause the side motor assignment of traffic of skidding too much to exceed the speed limit, and other single wheel is without driving, cause the forfeiture that drives tractive force, and when turning to, turn to inboard wheel rotating speed low, resistance wheel is larger, and turn to outboard wheels rotating speed fast, resistance wheel is less, required flow is different, because left and right motor is in parallel.This single pump double motor front-wheel assistant drive system left and right motor pressure is identical, cause while turning about the more difficult differential of realizing of front-wheel, but double pump+double motor scheme cost is lower relatively.
As Fig. 2, shown in Fig. 3, road grader front-wheel assistant drive system comprises driving engine, change speed gear box, assistive drive hydraulic efficiency pressure system and hydraulic control system, assistive drive hydraulic efficiency pressure system comprises the integrated pressure shutoff valve 112 that oil circuit communicates, load-sensing valve 113, controllable capacity pump 110, reducing valve 115, solenoid directional control valve 116, left, right motor 118, 119, shuttle valve 121, flow regulating valve 120, pressure shut-off valve 112 is connected with driving engine by jackshaft with the controllable capacity pump 110 of load-sensing valve 113, a left side, right motor 118, 119 is left with road grader respectively, off front wheel connects, and this hydraulic efficiency pressure system also comprises electro-hydraulic proportion reversing valve 122, electromagnetic proportion relief valve 114 and flow divider valve 117, a left side, right motor 118, 119 A, B mouth directly communicates with fuel tank by two check valves of flow divider valve 117 and the meta of electro-hydraulic proportion reversing valve 122, and hydraulic control system comprises drive pattern select switch 124, front-wheel assistive drive speed knob 127, front-wheel assistive drive tractive force knob 128, by front-wheel assistive drive speed knob 127, can adjust the control electric current of electro-hydraulic proportion reversing valve 122, the adjusting of speed while realizing front-wheel individual drive, by front-wheel assistive drive tractive force knob 128, can adjust the control electric current of electromagnetic proportion relief valve 114, control its pressure and change, while realizing front-wheel individual drive, drive the adjusting of tractive force, the left and right motor 118,119 of the utility model preferably adopts Double-discharge radial plunger piston motor.
As shown in Figure 4, drive pattern select switch 124 has the full wheel drive pattern 125 of back-wheel drive pattern 123, front-wheel assistive drive and three kinds of patterns of front-wheel individual drive 126.
Under acquiescence mode of operation, drive pattern select switch 124 is positioned at back-wheel drive pattern 123 positions, the electromagnet D1 of solenoid directional control valve 116 now, the electromagnet D2 of electro-hydraulic proportion reversing valve 122 and D3 are in power failure state, left, right motor 118 and 119 A, B mouth directly communicates with fuel tank by two check valves of flow divider valve 117 and the meta of electro-hydraulic proportion reversing valve 122, left, right motor 118 and 119 radial plunger cam press down and get back to plunger cavity in piston spring effect, left, right motor 118 and 119 one-tenth free gear states, propulsive effort is not provided, road grader only depends on back-wheel drive.
When drive pattern select switch 124 is manually placed in front-wheel individual drive pattern 126, manual handling gearbox shifting handle is at meta, change speed gear box does not provide power to trailing wheel, electro-hydraulic proportion reversing valve 122 electromagnet D2 obtain electric, the controllable capacity pump 110 of integrated pressure shutoff valve 112 and load-sensing valve 113 by jackshaft under driven by engine pressure oil output through electro-hydraulic proportion reversing valve 122 tops, flow divider valve 117 flows to left, right motor 118 and 119, and then flow back to fuel tank through electro-hydraulic proportion reversing valve 122 tops, simultaneously left, right motor 118 and 119 load high pressure feed back to load-sensing valve 113 by shuttle valve 121, the delivery pressure of controllable capacity pump 110 and the difference of load pressure are set institute by the spring of load-sensing valve 113 and are determined, at electro-hydraulic proportion reversing valve 122 front and back pressure reduction certain in the situation that, electromagnetic valve D2 that can corresponding adjusting electro-hydraulic proportion reversing valve 122 by front-wheel assistive drive speed knob 127 or the size of current of D3, thereby change the spool of electro-hydraulic proportion reversing valve 122 and the aperture position of valve body and size, and then change by flow divider valve 117 and a left side, right radial plunger piston motor 118 and 119 flow, therefore realize a left side, the adjusting of right radial plunger piston motor 118 and 119 output speed.
When setting front-wheel individual drive Speed Setting higher than a certain speed by front-wheel assistive drive speed knob 127, the D1 electromagnet of electromagnetic valve change-over valve 116 obtains electric, the pressure oil of now controllable capacity pump 110 outputs reduces pressure and arrives certain pressure through reducing valve 115, post-decompression pressure oil flows to respectively the control port of left and right motor 118 and 119 by solenoid directional control valve 116, this pressure oil compresses the part plunger cam retraction plunger cavity of left and right motor 118 and 119.Therefore make left and right motor 118 and 119 in low displacement condition.Thereby in the situation that flow is constant, can improve the output speed of left and right motor 118 and 119.
By front-wheel assistive drive tractive force knob 128, can regulate the size of current of electromagnetic proportion relief valve 114, thereby can change the oil pressure relief of electromagnetic proportion relief valve 114, a pressure confinement left side because of electromagnetic proportion relief valve 114, load pressure size when right double motor 118 and 119 work, on a left side, right motor 118 and 119 is when large discharge capacity or small displacement, in the situation that discharge capacity is certain, by changing the size of the pressure of electromagnetic proportion relief valve 114, can realize a left side, right motor 118 and 119 outputs drive the size of tractive force, thereby according to applying working condition, can regulate the tractive force size of front-wheel assistive drive, avoid being greater than because of tractive force the tractive force that adhesion value determines, cause skidding and inordinate wear of tire.
During front-wheel individual drive straight-line travelling (as shown in Figure 2), under nominal situation, pressure oil is by the pressure oil to left and right flows such as motor 118 and 119 shuntings of the meta of flow divider valve 117, the pressure feedback of left motor 118 is to the upper end of flow divider valve 117 simultaneously, the pressure feedback of right motor 119 is to the lower end of flow divider valve 117, flow divider valve 117 under feedback pressure in meta state, maintenance provides the flow equating to left and right motor 118 and 119, thereby guarantee that left and right motor 118 is consistent with 119 output speeds, realize straight-line travelling.
Because adhesion value changes while causing certain side motor propulsive effort to be greater than the tractive force that adhesive ability determines, skidding appears in this side motor, the left Double-discharge radial plunger piston motor 118 of take is example, now the pressure of left Double-discharge radial plunger piston motor 118 is less than the load pressure of right Double-discharge radial plunger piston motor 119, flow divider valve 117 moves up at the pressure of left motor 118 and the pressure-acting bottom spool of right motor 119, flow divider valve 117 is in the next, through throttling action, cause the hydraulic fluid flow rate that is diverted to left motor 118 to reduce to reduce with oil pressure, and the hydraulic fluid flow rate that flows to right motor 119 increases and oil pressure increases, when therefore the output speed of left motor 118 reduces, output torque reduces, avoid the left wheel wearing and tearing of skidding, when the output speed of right motor 119 increases simultaneously, output torque increases, improve output torque and the rotating speed of right motor 119, thereby keep left, right motor 118 is consistent with 119 output speeds, the roadholding that keeps road grader.By flow regulating valve 120, can provide certain repairing to low pressure side motor, avoid the emptying phenomenon of low pressure side motor.When left and right wheel-borne load is different, little with left side wheel load, right side wheels load is greatly listed as, and its service condition is similar to the above case, thereby guarantees the roadholding of road grader.
When road grader turns to, take right-hand turning to being example, now turn to the right wheel-borne load in inner side large, left outer wheel-borne load is little, the pressure of left motor 118 is less than the load pressure of right motor 119, flow divider valve 117 moves up at the pressure of left motor 118 and the pressure-acting bottom spool of right motor 119, flow divider valve 117 is in the next, through throttling action, cause the hydraulic oil pressure that is diverted to left motor 118 to reduce, and the hydraulic oil pressure that flows to right motor 119 increases, therefore the output torque of left motor 118 reduces, and the output torque of right motor 119 increases, simultaneously right motor 119 by flow regulating valve 120 left motor 118 certain repairing is provided, thereby guarantee the required flow of left motor 118 rotating speeds, avoid the emptying phenomenon of low pressure side motor, realize the differential steering of road grader.
When road grader retreats, the D3 electromagnet of electro-hydraulic proportion reversing valve 122 obtains electric, the pressure oil that now controllable capacity pump 110 is supplied with is through the next left and right motor 118 and 119 of flowing to of electro-hydraulic proportion reversing valve 122, and then through the check valve at flow divider valve 117 two ends and the next oil sump tank of electro-hydraulic proportion reversing valve 122, because road grader is in not operation of direction of retreat and less demanding to roadholding, so hydraulic oil is without the shunting of flow divider valve 117.
When drive pattern select switch 124 is manually placed in the full wheel drive pattern 125 of front-wheel assistive drive, tractive force when this pattern mainly increases road grader operation, gearbox-gear is placed in each gear of work, now the D2 electromagnet of electro-hydraulic proportion reversing valve 122 obtains electric, control D2 electromagnet current and be set to maximum spool aperture position, controllable capacity pump 110 pressure oil output arrive left through electro-hydraulic proportion reversing valve 122 and flow divider valve 117, right motor 118 and 119, when current wheel drive force is greater than traction, controllable capacity pump 110 delivery pressures are less than pressure shut-off valve 112 setting pressures, now controllable capacity pump 110 is in max.cap..When current wheel drive force is less than traction, controllable capacity pump 110 delivery pressures are greater than pressure shut-off valve 112 setting pressures, pressure shut-off valve 112 actions, controllable capacity pump 110 discharge capacities reduce, but because road grader trailing wheel continues to drive road grader, advance, controllable capacity pump 110 delivery pressures diminish, pressure shut-off valve 112 actions, controllable capacity pump 110 discharge capacities increase, thereby maintain front wheel rotation speed and rear wheel rotation speed matches.During the situations such as load variations, straight-line travelling and steering situation, principle of work situation corresponding to front-wheel individual drive pattern is similar.

Claims (3)

1. a road grader front-wheel assistive drive, system comprises driving engine, change speed gear box, assistive drive hydraulic efficiency pressure system and hydraulic control system, described assistive drive hydraulic efficiency pressure system comprises the integrated pressure shutoff valve (112) that oil circuit communicates, load-sensing valve (113), controllable capacity pump (110), reducing valve (115), solenoid directional control valve (116), left, right motor (118, 119), shuttle valve (121), flow regulating valve 120, described integrated pressure shutoff valve (112) is connected with driving engine by jackshaft with the controllable capacity pump (110) of load-sensing valve (113), a left side, right motor (118, 119) left with road grader respectively, off front wheel connects, and it is characterized in that, this hydraulic efficiency pressure system also comprises electro-hydraulic proportion reversing valve (122) and flow divider valve (117), a left side, right motor (118, 119) A, B mouth directly communicates with fuel tank by the meta of flow divider valve (117) and electro-hydraulic proportion reversing valve (122), and described hydraulic control system comprises drive pattern select switch (124), front-wheel assistive drive speed knob (127), can adjust the control electric current of electro-hydraulic proportion reversing valve (122), the adjusting of speed while realizing front-wheel individual drive by front-wheel assistive drive speed knob (127).
2. road grader front-wheel assistant drive system according to claim 1, it is characterized in that, this hydraulic efficiency pressure system also comprises electromagnetic proportion relief valve (114), and described hydraulic control system also comprises the front-wheel assistive drive tractive force knob (128) that drives tractive force to regulate in the time of can realizing front-wheel individual drive.
3. road grader front-wheel assistant drive system according to claim 1 and 2, is characterized in that, described left and right motor (118,119) is Double-discharge radial plunger piston motor.
CN201320457546.0U 2013-07-30 2013-07-30 Front-wheel auxiliary drive system for land leveler Withdrawn - After Issue CN203460698U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201320457546.0U CN203460698U (en) 2013-07-30 2013-07-30 Front-wheel auxiliary drive system for land leveler

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201320457546.0U CN203460698U (en) 2013-07-30 2013-07-30 Front-wheel auxiliary drive system for land leveler

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CN203460698U true CN203460698U (en) 2014-03-05

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103522896A (en) * 2013-07-30 2014-01-22 山东临工工程机械有限公司 Front wheel auxiliary drive system of land leveller

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103522896A (en) * 2013-07-30 2014-01-22 山东临工工程机械有限公司 Front wheel auxiliary drive system of land leveller
CN103522896B (en) * 2013-07-30 2016-03-30 山东临工工程机械有限公司 Front wheel auxiliary drive system of land leveller

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