CN204284037U - A kind of hydraulic system, pumping system and concrete pumping equipment - Google Patents
A kind of hydraulic system, pumping system and concrete pumping equipment Download PDFInfo
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- CN204284037U CN204284037U CN201420659643.2U CN201420659643U CN204284037U CN 204284037 U CN204284037 U CN 204284037U CN 201420659643 U CN201420659643 U CN 201420659643U CN 204284037 U CN204284037 U CN 204284037U
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Abstract
The utility model proposes a kind of hydraulic system, comprise the first oil cylinder and the second oil cylinder, the rodless cavity of described first oil cylinder is connected by pipeline with the rodless cavity of the second oil cylinder, described pipeline is provided with valve group, and described valve group comprises at least three kinds of working staties, in the first operative state, the conducting of described valve group large discharge, in a second operative state, described valve group throttling conducting, under the 3rd working state, described valve group is closed.The hydraulic system of said structure, when applying on concrete pumping equipment, preferably resolves concrete pumping equipment under the anti-pump state of low pressure, the problem that the stroke of oil cylinder shortens.On the other hand, the utility model also proposes a kind of pumping system comprising above-mentioned hydraulic system.Finally, the utility model also proposes a kind of concrete pumping equipment comprising above-mentioned hydraulic system or pumping system.
Description
Technical field
The utility model relates to engineering machinery field, particularly a kind of hydraulic system, pumping system and the concrete pumping equipment containing this pumping system or hydraulic system.
Background technique
In engineering machinery field, hydraulic system is used very general.Concrete pumping equipment is as the typical engineering machinery of one, comprise pumping system and delivery line, wherein, pumping system is made up of S valve, oscillating oil cylinder, two master cylinders and two conveying cylinders etc., S valve is for being communicated with delivery line and one of them conveying cylinder, oscillating oil cylinder is for driving S Vavle switching working state, and conveying cylinder drives with pump concrete by master cylinder, and master cylinder and oscillating oil cylinder control by hydraulic system.
Hydraulic system as shown in Figure 1 applies in concrete pumping equipment, wherein, master cylinder comprises the first oil cylinder 11 and the second oil cylinder 12, the rod chamber of the first oil cylinder 11 and the rod chamber of the second oil cylinder 12 are communicated with when high pressure pumping, by pipeline connection between the rodless cavity of the first oil cylinder 11 and the rodless cavity of the second oil cylinder 12, meanwhile, pipeline is also provided with the first cartridge valve 13 and the second cartridge valve 14, particularly, the first cartridge valve 13 and the second cartridge valve 14 are arranged in an integrated valve body.
High pressure pumping (comprises positive pump and anti-pump, positive pump is that the material in hopper is pumped into pouring location by delivery pipe, anti-pump is sucked back in hopper by the material in delivery pipe) time, first cartridge valve 13 and the second cartridge valve 14 are closed, the rodless cavity oil-feed of the first oil cylinder 11 (or second oil cylinder 12), piston rod in first oil cylinder 1 moves up under the effect of thrust, and the piston rod in the second oil cylinder 12 (or first oil cylinder 1) moves down.During low positive pressure pump, first cartridge valve 13 and the second cartridge valve 14 are opened, the rod chamber oil-feed of the first oil cylinder 11 (or second oil cylinder 12), piston rod in first oil cylinder 1 moves down under the effect of thrust, and the piston rod in the second oil cylinder 12 (or first oil cylinder 1) moves up.
And during the anti-pump of low pressure, the first cartridge valve 13 and the second cartridge valve 14 are opened, then by the rod chamber oil-feed of the first oil cylinder 11 (or second oil cylinder 12), the piston rod in the first oil cylinder 11, under the effect of thrust, moves down rapidly.When floor is higher, the concrete piston movement speed in conveying cylinder is very fast, when exceeding the highest commutation number of times, concrete piston wear can be caused too fast.Meanwhile, when oscillating oil cylinder motion is too frequent, commutation pressure can be caused to fall zero, and then occur that the stroke of master cylinder (i.e. the first oil cylinder 11 and the second oil cylinder 12) shortens.
In sum, how to improve the structure of hydraulic system and concrete pumping equipment, under solving the anti-pump state of low pressure, the problem that master cylinder stroke shortens, has become those skilled in the art to need the technical problem of solution badly.
Model utility content
In view of this, one of problem to be solved in the utility model is under how providing one can solve the anti-pump state of low pressure, and master cylinder stroke shortens the hydraulic system of problem.
Two of problem to be solved in the utility model how to provide a kind of pumping system comprising above-mentioned hydraulic system.
Three of problem to be solved in the utility model how to provide a kind of concrete pumping equipment comprising above-mentioned hydraulic system or pumping system.
For one of solving the problem, the utility model proposes a kind of hydraulic system, comprise the first oil cylinder and the second oil cylinder, the rodless cavity of described first oil cylinder is connected by pipeline with the rodless cavity of the second oil cylinder, described pipeline is provided with valve group, described valve group comprises at least three kinds of working staties, in the first operative state, and the conducting of described valve group large discharge, in a second operative state, described valve group throttling conducting, under the 3rd working state, described valve group is closed.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described valve group comprises the first passage, the second channel that are arranged in parallel and controls the control valve of described first passage and second channel break-make, in the first operative state, described control valve is for controlling the conducting of first passage large discharge; In a second operative state, described control valve is for controlling second channel throttling conducting, and first passage disconnects; Under the 3rd working state, described control valve is for controlling first passage and second channel all disconnects.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described first passage is provided with the first cartridge valve in parallel and the second cartridge valve, the filler opening of described first cartridge valve is communicated with the rodless cavity of the first oil cylinder with described second oil cylinder respectively with oil outlet; The filler opening of described second cartridge valve is communicated with the rodless cavity of the second oil cylinder with described first oil cylinder respectively with oil outlet; Described first cartridge valve is all communicated with described control valve with the control mouth of the second cartridge valve.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described second channel is provided with throttle valve or damping hole.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described second channel is also provided with the 3rd cartridge valve of connecting with described throttle valve, the filler opening of described 3rd cartridge valve is communicated with the rodless cavity of the second oil cylinder with described first oil cylinder respectively with oil outlet; The control mouth of described 3rd cartridge valve is communicated with described control valve.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described first passage is provided with the 4th cartridge valve, the filler opening of described 4th cartridge valve is communicated with the rodless cavity of the second oil cylinder with described first oil cylinder respectively with oil outlet; The control mouth of described 4th cartridge valve is communicated with described control valve.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described control valve is three position four-way directional control valve, the filler opening of described three position four-way directional control valve is communicated with pressure oil-source, and return opening is communicated with fuel tank, and two actuator ports control the break-make of first passage, second channel respectively.
As the improvement on the one hand of a kind of hydraulic system of the utility model, described valve group comprises variable throttle valve or electric proportional control valve.
The hydraulic system of said structure, when applying on concrete pumping equipment, preferably resolves concrete pumping equipment under the anti-pump state of low pressure, the problem that the stroke of oil cylinder shortens.
For solve the problem two, the utility model also proposes a kind of pumping system, comprise two conveying cylinders and for driving the hydraulic system of described conveying cylinder action, described hydraulic system is the hydraulic system as above described in any one, and described first oil cylinder carries the concrete piston of cylinder to be connected with the piston rod of the second oil cylinder respectively with two.
For solve the problem three, the utility model also proposes a kind of concrete pumping equipment, and described concrete pumping equipment comprises hydraulic system as above or pumping system as above.
Accompanying drawing explanation
The accompanying drawing forming a part of the present utility model is used to provide further understanding of the present utility model, and schematic description and description of the present utility model, for explaining the utility model, is not formed improper restriction of the present utility model.
Fig. 1 is the structure principle chart of a kind of hydraulic system in correlation technique;
Fig. 2 is the structure principle chart of a kind of hydraulic system of the utility model;
Fig. 3 is the structural representation of a kind of valve body of the utility model;
Fig. 4 is the structure principle chart of the another kind of hydraulic system of the utility model.
In Fig. 1, the corresponding relation of reference character is:
11 first oil cylinder 12 second oil cylinder 13 first cartridge valves
14 second cartridge valves
In Fig. 2 to Fig. 3, the corresponding relation of reference character is:
1 first oil cylinder 2 second oil cylinder 3 first cartridge valve
4 second cartridge valve 5 the 3rd cartridge valve 6 control valves
7 throttle valve 8 valve groups
Embodiment
It should be noted that, when not conflicting, the embodiment in the utility model and the feature in embodiment can combine mutually.Below with reference to the accompanying drawings and describe the utility model in detail in conjunction with the embodiments.
Hydraulic system as shown in Figure 2 and the valve body shown in Fig. 3, hydraulic system comprises the first oil cylinder 1, second oil cylinder 2 and valve group 8, first oil cylinder 1 and the second oil cylinder 2 include rod chamber and rodless cavity, and the rodless cavity of the rodless cavity of the first oil cylinder 1 and the second oil cylinder 2 is communicated with when low pressure pumping, valve group 8 is arranged on the oil circuit between the first oil cylinder 1 and the rodless cavity of the second oil cylinder 2.Particularly, valve group 8 comprises at least three kinds of working staties, in the first operative state, and the conducting of valve group 8 large discharge, i.e. the rodless cavity large discharge conducting of the first oil cylinder 1 and the second oil cylinder 2, the requirement to valve group 8 when can meet low positive pressure pump.In a second operative state, valve group 8 throttling conducting, due to valve group 8 throttling conducting, the rodless cavity of the first oil cylinder 1 and the second oil cylinder 2 be communicated with damping function, form back pressure when anti-pump, reduce oil cylinder astern speed, avoid the too fast commutation of oil cylinder, ensure the stroke of oil cylinder, prevent hydraulic system fault.And under the 3rd working state, valve group is in closed condition, namely the rodless cavity not conducting of the first oil cylinder 1 and the second oil cylinder 2, meets the requirement of high pressure pumping.It should be noted that, aforesaid valve group 8 can be arranged in a valve body (as shown in Figure 3), also three kinds of states can be realized by different valve bodies respectively, in this no limit.
Valve group 8 can have various structures to select, specifically, valve group comprises the first passage, the second channel that are arranged in parallel, and control the control valve 6 of first passage and second channel break-make, in the first operative state, control valve 6 is for controlling the conducting of first passage large discharge, and now, second channel can disconnect or conducting; In a second operative state, control valve 6 controls second channel throttling conducting, and first passage disconnects; Under the 3rd working state, control valve 6 controls first passage and second channel all disconnects.By arranging two passages, can subchannel being communicated with the rodless cavity of the first oil cylinder 1 and the second oil cylinder 2, control simple, convenient, easily realize.
In technique scheme, as shown in Figure 2, first passage is provided with the first cartridge valve 3 and the second cartridge valve 4 in parallel, the filler opening of the first cartridge valve 3 is communicated with the rodless cavity of the second oil cylinder 2 with the first oil cylinder 1 respectively with oil outlet, and the filler opening of the second cartridge valve 4 and oil outlet are communicated with the rodless cavity of the first oil cylinder 1 with the second oil cylinder 2 respectively; First cartridge valve 3 is all communicated with control valve 6 with the control mouth of the second cartridge valve 4.Controlled the opening and closing of the first cartridge valve 3 and the second cartridge valve 4 by control valve 6, and cartridge valve conducting flow is large, therefore, the requirement of under can meeting the first working state, valve group 8 under valve group 8 large discharge conducting and the 3rd working state being closed.It should be noted that, first passage also can be arranged the 4th cartridge valve (without the need to two cartridge valves in parallel), the filler opening of the 4th cartridge valve is communicated with the rodless cavity of the first oil cylinder 1 with the second oil cylinder 2 respectively with oil outlet, the control mouth of the 4th cartridge valve is communicated with control valve 6, because the filler opening of cartridge valve and oil outlet can exchange, therefore, its working principle cartridge valve in parallel with arranging two is similar.
Further, in technique scheme, second channel is provided with throttle valve 7 or damping hole, and its quantity and type can be selected as required, due to the effect of throttle valve 7 or damping hole, under can meeting the second working state, to the requirement of valve group 8 throttling conducting.It should be noted that, damping hole can be special damping, also can be the selector valve of small flow, as bi-bit bi-pass selector valve, can small flow conducting, and also can close; Throttle valve 7 can adopt the throttle valve of adjustable flow, for the throttle valve of non-adjustable flow, a switch valve of can connecting realizes controlling the break-make of second channel, particularly, second channel is also provided with the 3rd cartridge valve 5 of connecting with throttle valve 7, the filler opening of the 3rd cartridge valve 5 is communicated with the rodless cavity of the first oil cylinder 1 with the second oil cylinder 2 respectively with oil outlet, and the control mouth of the 3rd cartridge valve 5 is communicated with control valve 6.Carry out break-make control by the 3rd cartridge valve 5 pairs of second channels, it is convenient to control.
Control valve 6 can have multiple choices, is specially three position four-way directional control valve in Fig. 2, and the filler opening of three position four-way directional control valve is communicated with pressure oil-source, and return opening is communicated with fuel tank, by two actuator ports, can control the break-make of first passage, second channel respectively.Control valve 6 can be solenoid directional control valve, pilot operated directional control valve or hand-operated direction valve.
For valve group 8, as shown in Figure 4, variable throttle valve or electric proportional control valve can also be adopted.By regulating the flow area of variable throttle valve or electric proportional control valve, the switching of first, second and third working state can be realized.
The working principle of hydraulic system shown in Fig. 2 is as follows: when the upper work of control valve 6, fluid in oil circuit control enters to the 3rd cartridge valve 5 through the upper of control valve 6, under the effect of pressure oil, 3rd cartridge valve 5 is in lockup state, and the first cartridge valve 3 is communicated with fuel tank with the oil circuit control of the second cartridge valve 4, two cartridge valves are all on state, and the rodless cavity of the first oil cylinder 1 and the rodless cavity of the second oil cylinder 2 are on state.Now, hydraulic system is in large discharge oil circuit opening state.When concrete pumping equipment is in low positive pressure pump, this oil circuit works.
As shown in Figure 2, when the bottom of control valve 6 works, fluid in oil circuit control enters to the first cartridge valve 3 and the second cartridge valve 4 through the bottom of control valve 6, under the effect of pressure oil, first cartridge valve 3 and the second cartridge valve 4 are in lockup state, and the oil circuit control of the 3rd cartridge valve 5 is communicated with fuel tank, 3rd cartridge valve 5 is on state, now, the rodless cavity of the first oil cylinder 1 is communicated with the rodless cavity of the second oil cylinder 2, because throttle valve 7 can slow down the flow of fluid through the 3rd cartridge valve 5 and throttle valve 7.Now, valve group 8 is in small flow oil circuit opening state (that is, throttling on state).When concrete pumping equipment is in the anti-pump of low pressure (as washing operating mode), this oil circuit works.
As shown in Figure 2, when the meta work of control valve 6, fluid in oil circuit control enters to the first cartridge valve 3, second cartridge valve 4 and the 3rd cartridge valve 5 through control valve 6 meta, under the effect of pressure oil, first cartridge valve 3, second cartridge valve 4 and the 3rd cartridge valve 5 are all in lockup state, now, the rodless cavity of the first oil cylinder 1 is not communicated with the rodless cavity of the second oil cylinder 2.When concrete pumping equipment is in high pressure pumping state, this oil circuit works.
As shown in Figure 4, control valve 6 is specially electric proportional control valve, and during high pressure pumping, 2/2-way solenoid directional control valve dead electricity, Proportional valve is in closed condition, now, is not communicated with between the first oil cylinder 1 and the rodless cavity of the second oil cylinder 2.During low positive pressure pump, 2/2-way solenoid directional control valve obtains electric, and Proportional valve is opened, and the first oil cylinder 1 is communicated with the rodless cavity of the second oil cylinder 2.And when the anti-pump of low pressure, according to the size of the input current of 2/2-way solenoid directional control valve, certain aperture can be opened, thus complete the anti-pump of washing.
On the other hand, the utility model also proposes a kind of pumping system, comprises two conveying cylinders and for driving the hydraulic system of conveying cylinder action, hydraulic system is specially hydraulic system as above.First oil cylinder 1 carries the concrete piston of cylinder to be connected with the piston rod of the second oil cylinder 2 respectively with two.
Finally, the utility model also proposes a kind of concrete pumping equipment, specifically comprises hydraulic system as above or pumping system as above.
In technique scheme, when pumping system or concrete pumping equipment are in conventional high-pressure pumping, control valve 6 is in meta, and rodless cavity is not communicated with; When concrete pumping equipment is in low positive pressure pump, the upper work of control valve 6, the first cartridge valve 3, second cartridge valve 4 is on state, the 3rd cartridge valve 5 locking; When concrete pumping equipment is in the anti-pump of low pressure, the work of control valve 6 bottom, first cartridge valve 3, second cartridge valve 4 is in closed condition, 3rd cartridge valve 5 conducting, now can pass through the area that throttling breakover element (as throttle valve 7) reduces the first oil cylinder 1 and the second oil cylinder 2 conducting, avoid the stroke of the first oil cylinder 1 and the second oil cylinder 2 to shorten.
Above-mentioned concrete pumping equipment, compared with existing concrete pumping equipment, under preferably resolving anti-pump state, the problem that master cylinder stroke shortens.
The foregoing is only preferred embodiment of the present utility model; not in order to limit the utility model; all within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.
Claims (10)
1. a hydraulic system, comprise the first oil cylinder (1) and the second oil cylinder (2), the rodless cavity of described first oil cylinder (1) is connected by pipeline with the rodless cavity of the second oil cylinder (2), described pipeline is provided with valve group (8), it is characterized in that, described valve group (8) comprises at least three kinds of working staties, in the first operative state, the large discharge conducting of described valve group (8), in a second operative state, the throttling conducting of described valve group (8), under the 3rd working state, described valve group (8) is closed.
2. hydraulic system according to claim 1, it is characterized in that, described valve group (8) comprises the first passage, the second channel that are arranged in parallel and controls the control valve (6) of described first passage and second channel break-make, in the first operative state, described control valve (6) is for controlling the conducting of first passage large discharge; In a second operative state, described control valve (6) is for controlling second channel throttling conducting, and first passage disconnects; Under the 3rd working state, described control valve (6) is for controlling first passage and second channel all disconnects.
3. hydraulic system according to claim 2, it is characterized in that, described first passage is provided with the first cartridge valve (3) in parallel and the second cartridge valve (4), the filler opening of described first cartridge valve (3) is communicated with the rodless cavity of the first oil cylinder (1) with described second oil cylinder (2) respectively with oil outlet; The filler opening of described second cartridge valve (4) is communicated with the rodless cavity of the second oil cylinder (2) with described first oil cylinder (1) respectively with oil outlet; Described first cartridge valve (3) is all communicated with described control valve (6) with the control mouth of the second cartridge valve (4).
4. hydraulic system according to claim 2, is characterized in that, described second channel is provided with throttle valve (7) or damping hole.
5. hydraulic system according to claim 4, it is characterized in that, described second channel is also provided with the 3rd cartridge valve (5) of connecting with described throttle valve (7), the filler opening of described 3rd cartridge valve (5) is communicated with the rodless cavity of the second oil cylinder (2) with described first oil cylinder (1) respectively with oil outlet; The control mouth of described 3rd cartridge valve (5) is communicated with described control valve (6).
6. hydraulic system according to claim 2, it is characterized in that, described first passage is provided with the 4th cartridge valve, the filler opening of described 4th cartridge valve is communicated with the rodless cavity of the second oil cylinder (2) with described first oil cylinder (1) respectively with oil outlet; The control mouth of described 4th cartridge valve is communicated with described control valve (6).
7. the hydraulic system according to any one of claim 2-6, it is characterized in that, described control valve (6) is three position four-way directional control valve, the filler opening of described three position four-way directional control valve is communicated with pressure oil-source, return opening is communicated with fuel tank, and two actuator ports control the break-make of first passage, second channel respectively.
8. hydraulic system according to claim 1, is characterized in that, described valve group (8) comprises variable throttle valve or electric proportional control valve.
9. a pumping system, comprise two conveying cylinders and for driving the hydraulic system of described conveying cylinder action, it is characterized in that, the hydraulic system of described hydraulic system according to any one of claim 1 to 8, described first oil cylinder (1) carries the concrete piston of cylinder to be connected with the piston rod of the second oil cylinder (2) respectively with two.
10. a concrete pumping equipment, is characterized in that, comprises the hydraulic system according to any one of claim 1 to 8, or comprises pumping system according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420659643.2U CN204284037U (en) | 2014-11-06 | 2014-11-06 | A kind of hydraulic system, pumping system and concrete pumping equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420659643.2U CN204284037U (en) | 2014-11-06 | 2014-11-06 | A kind of hydraulic system, pumping system and concrete pumping equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204284037U true CN204284037U (en) | 2015-04-22 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420659643.2U Expired - Fee Related CN204284037U (en) | 2014-11-06 | 2014-11-06 | A kind of hydraulic system, pumping system and concrete pumping equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204284037U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106481610A (en) * | 2016-12-08 | 2017-03-08 | 三汽车制造有限公司 | Double dynamical pumping machine switching valve group, double dynamical pumping system and machinery |
-
2014
- 2014-11-06 CN CN201420659643.2U patent/CN204284037U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106481610A (en) * | 2016-12-08 | 2017-03-08 | 三汽车制造有限公司 | Double dynamical pumping machine switching valve group, double dynamical pumping system and machinery |
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Legal Events
| Date | Code | Title | Description |
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| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150422 Termination date: 20171106 |
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| CF01 | Termination of patent right due to non-payment of annual fee |