CN103062024A

CN103062024A - High-low pressure switching method of double-cylinder pumping device and hydraulic control system and equipment thereof

Info

Publication number: CN103062024A
Application number: CN201210574745XA
Authority: CN
Inventors: 曹奎; 周小宾; 李华; 王佳茜
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Priority date: 2012-12-26
Filing date: 2012-12-26
Publication date: 2013-04-24
Anticipated expiration: 2032-12-26
Also published as: CN103062024B

Abstract

The high-low pressure switching method of the double-cylinder pumping device comprises the following steps: firstly, stopping high-pressure pumping operation of the double-cylinder pumping device, so that the double-cylinder pumping device is in a state that high-pressure pumping is to be switched and is kept for a first preset delay time ta; secondly, enabling the rodless cavities of the first main oil cylinder and the second main oil cylinder to be communicated with each other to form a communicated cavity, and enabling the rod cavities of the first main oil cylinder and the second main oil cylinder to be communicated with the first working oil path and the second working oil path respectively, so that the double-cylinder pumping device is in a low-pressure pumping preparation state and keeps a second preset delay time tb; and thirdly, the double-cylinder pumping device is in a low-pressure pumping operation state. In addition, the invention also provides a hydraulic control system of the double-cylinder pumping device and pumping equipment. The invention realizes the sequential control of high-low pressure switching, and keeps certain buffering time after corresponding steps, so that the system is operated after the oil circuit is stable, the hydraulic impact is effectively relieved, and the main oil cylinder works stably.

Description

The high low pressure switching method of twin-tub pumping installations and hydraulic control system and equipment

Technical field

The present invention relates to a kind of controlling method of twin-tub pumping installations, particularly, relate to a kind of high low pressure switching method of twin-tub pumping installations.In addition, the pumping equipment that the invention still further relates to a kind of hydraulic control system of twin-tub pumping installations and comprise this hydraulic control system.Twin-tub pumping installations of the present invention is mainly used in the pumping of sticky material, typically concrete pump for example.

Background technique

The sticky material such as concrete, mud is engineering construction field structural material commonly used, these sticky materials typically undertaken pumpings by twin-tub pumping installations (such as concrete pump, mortar pump etc.), the twin-tub pumping installations mainly passes through the control of its hydraulic control system, so that sticky material is carried continuously along pipeline.

In order to help to understand, typically, for example send device with the Concrete Double cylinder pump, the Concrete Double cylinder pump send device to generally comprise two master cylinders (being also referred to as " master hydraulic cylinder "), two conveying cylinders (being also referred to as " concrete cylinder "), two pumping pistons, two oscillating oil cylinders, hopper and distributing valves, these component assembles consist of the Concrete Double cylinder pump and send device together.With regard to the hydraulic control system that this Concrete Double cylinder pump send device, mainly refer to be connected to corresponding hydraulic control circuit on master cylinder and the oscillating oil cylinder.

Particularly, for example, the rod chamber of two master cylinders is interconnected, rodless cavity is connected to main reversing valve, this main reversing valve is connected in main oil-feed oil circuit and fuel tank, by the commutation of main reversing valve optionally so that the rodless cavity of the first master cylinder in two master cylinders is communicated with main oil-feed oil circuit and the rodless cavity of the second master cylinder is communicated with fuel tank, perhaps so that the rodless cavity of the first master cylinder is communicated with fuel tank and the rodless cavity of the second main oil 5 is communicated with main oil-feed oil circuit.Because the rod chamber of two master cylinders is interconnected and is closed with hydraulic oil, hydraulic oil in the rod chamber of these two master cylinders plays the effect of driving medium, thereby can realize the alternately flexible of two master cylinders by the rodless cavity oil-feed to two master cylinders alternately.Two pumping pistons 1 lay respectively at two and carry in the cylinders and be connected to drive corresponding pumping piston 1 alternating motion with the piston rod of master cylinder respectively, with alternately pumping or suction sticky material, for example concrete.

It should be noted that at this, the rod chamber that two master cylinders are not limited to two above-mentioned master cylinders is interconnected to consist of the situation of communicated cavity, selectively, the rodless cavity that also can adopt two master cylinders is interconnected and consists of the structural type of communicated cavity, and the rod chamber of two master cylinders consists of actuator chamber respectively and is connected with selector valve in this case.For those skilled in the art knownly, rodless cavity is high pressure pumping state as the situation of actuator chamber so that the rod chamber of two master cylinders is interconnected, and rod chamber is low pressure pumping state as the situation of actuator chamber so that the rodless cavity of two master cylinders is interconnected.

In the twin-tub pumping installations of reality, the rodless cavity of two master cylinders or rod chamber can optionally as communicated cavity or actuator chamber, this generally realizes by high/low pressure cut-over valve by switching.The high/low pressure cut-over valve that adopts in the hydraulic control system of twin-tub pumping installations can have various ways, is not limited to the high/low pressure cut-over valve that six two-way plug-in valves of employing shown in Figure 1 consist of.

But, in the high low pressure handoff procedure of present twin-tub pumping installations, often each control valve in the hydraulic control system of twin-tub pumping installations is switched simultaneously by force, this causes when carrying out the high low pressure switching, hydraulic shock in the hydraulic control system is very large, and master cylinder work is not steady, and the hydraulic oil of communicated cavity sealing changes larger in different handoff procedures, can not control, and then it is elongated or shorten to cause master cylinder to drive stroke relatively stablely.That is to say that existing twin-tub pumping installations is not to operate according to relatively scientific and reasonable operating procedure in high low pressure handover operation process, switches but optionally carry out high low pressure, this has caused the shortcoming of above-mentioned twin-tub pumping installations.Especially, when there is the plugging phenomenon in sticky material delivery pipe (for example concrete delivery pipe) or has plugging trend, twin-tub pumped difficulty, at this moment blindly, random low high pressure switches, tend to aggravate the degree of plugging, so that system overpressure, even the serious accidents such as booster appear.

In view of the defects of prior art, need to provide a kind of high low pressure switching method of twin-tub pumping installations of more science.

Summary of the invention

The present invention's technical problem at first to be solved provides a kind of high low pressure switching method of twin-tub pumping installations, this high low pressure switching method can so that the high low pressure of twin-tub pumping installations switch more steadily reliable, thereby improve the pumpdown quality.

Further, technical problem to be solved by this invention provides a kind of hydraulic control system of twin-tub pumping installations, and this hydraulic control system can realize more reliably that the high low pressure of twin-tub pumping installations switches.

In addition, the technical problem that the present invention also will solve provides a kind of pumping equipment, and the twin-tub pumping installations of this pumping equipment can realize more reliably that high low pressure switches, so that the service behaviour of pumping equipment is more stable.

In order to solve the problems of the technologies described above, a kind of form of implementation for be sent to low pressure pumping switching from high-pressure service pump as high low pressure switching method of the present invention, the invention provides a kind of high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second working oil path of the first and second master cylinder oil inlet and oil returns that are respectively applied to this twin-tub pumping installations, alternately oil-feed and the oil return of this first and second working oil path, to realize the alternately flexible of described the first and second master cylinders, wherein, described high low pressure switching method comprises the steps: first, be under the state of high pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path stop the conveying liquid force feed, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure pumping; The second so that described the first and second master cylinders rodless cavity separately is interconnected to form communicated cavity, and so that this communicated cavity all end with respect to described the first and second working oil path; And so that the rod chamber of the rod chamber of described the first master cylinder and described the second master cylinder relative to each other end, and so that the rod chamber of this first master cylinder is communicated with described the first working oil path, the rod chamber of this second master cylinder is communicated with described the second working oil path, thereby so that described twin-tub pumping installations is in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness; The 3rd, by described the first and second working oil path so that alternately oil-feed and the oil return of the rod chamber of the rod chamber of described the first master cylinder and the second master cylinder, thereby so that described twin-tub pumping installations is in low pressure pumping job state.

As a kind of preferred form, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve, in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit, high pressure pumping on the first working oil path or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the described first step and the second scheduled delay tb in the described second step by the inquiry experts database; Perhaps the hydraulic control system of described twin-tub pumping installations is the Closed Hydraulic control system, wherein said the first and second working oil path are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that the one oil-feed in described the first and second working oil path by the positive and negative of described oil hydraulic pump, the another one oil return, in described first step, the high pressure pumping that detects when stopping the high pressure pumpdown of described twin-tub pumping installations on described the first working oil path or the second working oil path stops constantly oil pressure, and stop oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the described first step and the second scheduled delay tb in the described second step by the inquiry experts database, comprise in the described experts database that each high pressure pumping stops constantly corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value.

Preferably, described the first scheduled delay ta and the second scheduled delay tb are respectively 0-10s.

Preferably, described the first and second working oil path are connected in described the first and second master cylinders via high/low pressure cut-over valve respectively, in described second step, by the switching of described high/low pressure cut-over valve so that described twin-tub pumping installations is in described low pressure pumping readiness.

Preferably, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, and wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve; In described first step, by controlling described main reversing valve so that described the first and second working oil path all end with described main oil-feed oil circuit and main oil return circuit, thereby so that this first and second working oil path stops the conveying liquid force feed; In described third step, by controlling described main reversing valve so that described the first and second working oil path alternately with described main oil-feed oil circuit and main oil return circuit) one and another one be communicated with, thereby by described the first and second working oil path so that alternately oil-feed and the oil return of the rod chamber of the rod chamber of described the first master cylinder and the second master cylinder.

Preferably, described main reversing valve is O type three position four-way directional control valve.

Particularly, described twin-tub pumping installations is that the Concrete Double cylinder pump send device.

A kind of form of implementation for be sent to high pressure pumping switching from low pressure pump as high low pressure switching method of the present invention, the invention provides a kind of high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second working oil path of the first and second master cylinder oil inlet and oil returns that are respectively applied to this twin-tub pumping installations, alternately oil-feed and the oil return of this first and second working oil path, to realize the alternately flexible of described the first and second master cylinders, wherein, described high low pressure switching method comprises the steps: first, be under the state of low pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path stop the conveying liquid force feed, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping; The second so that described the first and second master cylinders rod chamber separately is interconnected to form communicated cavity, and so that this communicated cavity all end with respect to described the first and second working oil path; And so that the rodless cavity of the rodless cavity of described the first master cylinder and described the second master cylinder relative to each other end, and so that the rodless cavity of this first master cylinder is communicated with described the first working oil path, the rodless cavity of this second master cylinder is communicated with described the second working oil path, thereby so that described twin-tub pumping installations is in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness; The 3rd, by described the first and second working oil path so that alternately oil-feed and the oil return of the rodless cavity of the rodless cavity of described the first master cylinder and the second master cylinder, thereby so that described twin-tub pumping installations is in high pressure pumping job state.

As a kind of preferred form, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve, in described first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit, low pressure pumping on the first working oil path or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database; Perhaps the hydraulic control system of described twin-tub pumping installations is the Closed Hydraulic control system, wherein said the first and second working oil path are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that the one oil-feed in described the first and second working oil path by the positive and negative of described oil hydraulic pump, the another one oil return, in described first step, the low pressure pumping that detects when stopping the low pressure pumpdown of described twin-tub pumping installations on described the first working oil path or the second working oil path stops constantly oil pressure, and stop oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database, comprise in the described experts database that each low pressure pumping stops the moment corresponding the first scheduled time value of oil pressure value and the second scheduled time value.

Preferably, described the first scheduled time ta ' and the second scheduled time tb ' are respectively 0-10s.

Preferably, described the first and second working oil path are connected in described the first and second master cylinders via high/low pressure cut-over valve respectively, in described second step, by the switching of described high/low pressure cut-over valve so that described twin-tub pumping installations is in described high pressure pumping readiness.

Preferably, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, and wherein said the first and second working oil path are connected in main oil-feed oil circuit and main oil return circuit via main reversing valve; In described first step, by controlling described main reversing valve so that described the first and second working oil path all end with described main oil-feed oil circuit and main oil return circuit, thereby so that this first and second working oil path stops the conveying liquid force feed; In described third step, by controlling described main reversing valve so that described the first and second working oil path alternately with described main oil-feed oil circuit and main oil return circuit) one and another one be communicated with, thereby by described the first and second working oil path so that alternately oil-feed and the oil return of the rodless cavity of the rodless cavity of described the first master cylinder and the second master cylinder.

Particularly,, described twin-tub pumping installations is that the Concrete Double cylinder pump send device.

Further, the invention provides a kind of hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity of the first master cylinder of described twin-tub pumping installations and rodless cavity and the rod chamber of rod chamber and the second master cylinder by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path and the second working oil path, this first working oil path and the second working oil path are connected in main oil-feed oil circuit and main oil return circuit by the main reversing valve of electric control reversing valve form, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on described main reversing valve and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, control described main reversing valve and stop the current pumpdown that carries out, and keep pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after the high low pressure state switches, keep the second predetermined hold-time; The 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

Preferably, described main oil-feed oil circuit, be provided with the oil pressure detection device on the first working oil path or the second working oil path, this oil pressure detection device is electrically connected on described controller and is transferred to this controller with the fuel injection pressure signal that will detect, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops moment fuel injection pressure signal and determines described the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database, described experts database is stored in the described controller or in the external server, comprises in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value.

Form of implementation as the hydraulic control system of another kind of twin-tub pumping installations, the present invention also provides the hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity of the first master cylinder of described twin-tub pumping installations and rodless cavity and the rod chamber of rod chamber and the second master cylinder by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path and the second working oil path, this first working oil path and the second working oil path are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that the one oil-feed in described the first and second working oil path by the positive and negative of described oil hydraulic pump, the another one oil return, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, the automatically controlled rotating driving device of controlling described oil hydraulic pump to be stopping the current pumpdown that carries out, and keeps pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and the high low pressure state switches rear second predetermined hold-time that keeps; The 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

Preferably, be provided with the oil pressure detection device on described the first working oil path or the second working oil path, this oil pressure detection device is electrically connected on described controller and is transferred to this controller with the fuel injection pressure signal that will detect, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops moment fuel injection pressure signal and determines described the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database, described experts database is stored in the described controller or in the external server, comprises in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value.

In addition, the invention provides a kind of pumping equipment, it comprises the hydraulic control system of twin-tub pumping installations and this twin-tub pumping installations, and wherein, described hydraulic control system is above-mentioned hydraulic control system.

Pass through technique scheme, high low pressure switching method of the present invention with respect to existing techniques in realizing accurate time-oriented sequential control, namely so that stop pumping, the high low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in the prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by after corresponding operating procedure, keeping certain buffer time, so that the oil circuit of hydraulic control system carries out next step operation after stablizing again, this has alleviated the hydraulic shock in the hydraulic control system effectively, so that master cylinder stable working, and the hydraulic oil in handoff procedure so that in the communicated cavity is relatively stable, thereby relative efficiency ground keeps constant so that master cylinder drives stroke.The high low pressure that high low pressure switching method of the present invention can be applied to the twin-tub pumping installations of various existing forms at large switches, and it has general applicability and using value, and especially it can adopt automatically controlled form, thereby realizes automatically control.

Other features and advantages of the present invention will partly be described in detail in embodiment subsequently.

Description of drawings

Following accompanying drawing is used to provide a further understanding of the present invention, and consists of the part of specification, and itself and following embodiment one are used from explanation the present invention, but protection scope of the present invention is not limited to following the drawings and the specific embodiments.In the accompanying drawings:

Fig. 1 is the hydraulic schematic diagram of hydraulic control system of the twin-tub pumping installations of the specific embodiment of the invention.

Fig. 2 is the control sequential chart that the high low pressure of hydraulic control system shown in Figure 1 switches.

Fig. 3 is the step block diagram of the high low pressure switching method of the specific embodiment of the invention, and the high low pressure switching method of this embodiment is used for control twin-tub pumping installations and switches from high pressure pumping job state to low pressure pumping job state.

Fig. 4 is the step block diagram of the high low pressure switching method of the another kind of embodiment of the present invention, and the high low pressure switching method of this embodiment is used for control twin-tub pumping installations and switches from low pressure pumping job state to high pressure pumping job state.

Description of reference numerals:

1 first master cylinder; The 1a rodless cavity;

The 1b rod chamber; 2 second master cylinders;

The 2a rodless cavity; The 2b rod chamber;

3 main reversing valves; 4 oil pressure detection devices;

5 main oil-feed oil circuits; 6 main oil return circuits;

7 first working oil path; 8 second working oil path;

9 switch hydraulic control oil circuit selector valve; 10 switch with hydraulic control oil-feed oil circuit;

11 switching hydraulic control oil return circuits; 12 first pilot-controlled working oil circuits;

13 second pilot-controlled working oil circuits; 14 pilot-actuated valves;

15 guide's oil-feed oil circuits; 16 guide's oil return circuits;

17 first guide's pilot-controlled working oil circuits; 18 second guide's pilot-controlled working oil circuits.

Embodiment

Below in conjunction with accompanying drawing the specific embodiment of the present invention is elaborated, should be understood that, embodiment described herein only is used for description and interpretation the present invention, and protection scope of the present invention is not limited to following embodiment.

Major technique design of the present invention is to provide a kind of high low pressure switching method of twin-tub pumping installations, so that the switching of the high low pressure of twin-tub pumping installations is controlled in order, thereby improves the smooth operation that high low pressure switches, and improves the pumpdown quality.Need to prove; although Fig. 1 of the present invention has shown a kind of high/low pressure cut-over valve form of twin-tub pumping installations; but the technical conceive of high low pressure switching method of the present invention is not limited to adopt hydraulic control system shown in Figure 1 to realize; because the hydraulic connecting structure basic simlarity of the hydraulic control system of twin-tub pumping installations; also there are various known forms in high/low pressure cut-over valve; we's high low pressure switching method can be applicable to the high low pressure switching controls of twin-tub pumping installations at large; therefore; any twin-tub pumping installations; specific constructive form regardless of its hydraulic control system; as long as adopt high low pressure switching method of the present invention, it all belongs to protection scope of the present invention.In addition, the term of " the high pressure pumping " and " low pressure pumping " described in hereinafter describing, be the general standard term of art of those skilled in the art, wherein " high pressure pumping " refer to that the rod chamber of the first and second master cylinders of twin-tub pumping installations is interconnected with as communicated cavity, and rodless cavity is as the situation of actuator chamber, " low pressure pumping " refers to that the rodless cavity of the first and second master cylinders is interconnected with as communicated cavity, and rod chamber is as the situation of actuator chamber, so-called " high pressure " is relative technological concept with " low pressure ", it mainly is to refer under the basicly stable situation of main oil-feed oil circuit oil pressure and flow the outlet pressure of the sticky material of pumping.

In order to help to understand, twin-tub pumping installations and hydraulic control system thereof are below at first described, need to prove, the structure of relevant twin-tub pumping installations and hydraulic control system thereof is similar substantially, so the following high low pressure switching method of the present invention can be used for the switching controls of twin-tub pumping installations at large.

Referring to shown in Figure 1, as mentioned above, the main structure of twin-tub pumping installations is known ground, and it generally comprises two master cylinders (i.e. the first master cylinder 1 and the second master cylinder 2), two conveying cylinders (being also referred to as " concrete cylinder "), two pumping pistons, two oscillating oil cylinders, hopper and distributing valves.Wherein, carry cylinder, pumping piston, oscillating oil cylinder, hopper and distributing valve etc. to show in Fig. 1, its technical conceive with the following high low pressure switching method of the present invention is not directly related, therefore in this only simply description.Briefly, two pumping pistons lay respectively at two and carry in the cylinders and connect with the piston rod of the first and second master cylinders 1,2 respectively, with by the first and second master cylinders 1,2 drive corresponding pumping piston alternating motion, thus alternately pumping or suction sticky material.The material mouth of two conveying cylinders is connected in discharge port and the material conveying pipe (for example concrete conveying pipe) of hopper by distributing valve, distributing valve drives by oscillating oil cylinder, so that carry the material mouth of cylinder optionally to be communicated with discharge port or the material conveying pipe of hopper.In addition, the hydraulic control circuit of above-mentioned oscillating oil cylinder is uncorrelated with technical conceive of the present invention, will not describe when therefore describing hydraulic control system hereinafter.

With regard to the hydraulic control system of twin-tub pumping installations, its hydraulic connecting structure is similarly substantially, particularly, the rodless cavity 1a of the first master cylinder 1 is connected the rodless cavity 2a of the second master cylinder 2 and is connected with rod chamber 2b by pipeline and connects high/low pressure cut-over valve (having the corresponding hydraulic fluid port that connects on the high/low pressure cut-over valve) with rod chamber 1b, this high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, and this first working oil path 7 and the second working oil path 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 by main reversing valve 3.Be uniquely, be provided with oil pressure detection device 4 on the main oil-feed oil circuit 5 of the hydraulic control system of twin-tub pumping installations of the present invention, such as oil pressure sensor or oil pressure gauge etc., wherein oil pressure sensor can be electrically connected on controller or the display unit.

Wherein, there is various ways in the prior art in high/low pressure cut-over valve, such as disclosed high/low pressure cut-over valve among CN200520109691.5, CN01273407.1, the CN200320101853.1 etc., its fundamental function all is identical, namely pass through the control high/low pressure cut-over valve, can be optionally so that the twin-tub pumping installations be in high pressure pumping state or low pressure pumping state.Particularly, at described low pressure pumping state, switching by described high/low pressure cut-over valve, so that the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected with as communicated cavity, and this communicated cavity seals with respect to the outside, and the rod chamber 1b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively; Under described high pressure pumping state, switching by described high/low pressure cut-over valve, so that the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is interconnected with as communicated cavity, and this communicated cavity seals with respect to the outside, and the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is communicated with the first working oil path 7 and the second working oil path 8 respectively.Need to prove at this, the statement of above-mentioned " connection ", belong to a kind of statement of simplifying, the technological concept of its expression is the implication of " hydraulic oil can two-way flow by ", for example, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected, and that is to say that the interior hydraulic oil of rodless cavity 1a of the first master cylinder 1 can flow in the rodless cavity 2a of the second master cylinder 2, and vice versa; For another example, the rodless cavity 1a of the first master cylinder 1 is communicated with the first working oil path 7, when namely the hydraulic oil on the first working oil path 7 can flow to the rodless cavity 1a(rodless cavity 1a oil-feed of the first master cylinder 1), on the contrary the hydraulic oil in the rodless cavity 1a of the first master cylinder 1 also can flow to (during rodless cavity 1a oil return) on the first working oil path 7.That is to say that the concept of above-mentioned " connection " both can be the state that oil circuit is in normal open, also can be to have relevant valve on the oil circuit, but thereby this valve can be opened the state that is communicated with can realized under the effect of the hydraulic oil that described oil circuit flows.For example, in six formed high/low pressure cut-over valves of two-way plug-in valve of employing shown in Figure 1, when liquid controling cavity (the being the Returnning spring chamber) decompression of the first two-way plug-in valve C1, hydraulic oil in the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 all can be pushed the spool of the first two-way plug-in valve C1 open when the twin-tub pumping installations is worked, and realizes connected state.Therefore, above-mentioned " connection " should from the hydraulic oil of essence can two-way flow implication understand, should not carry out unreasonably narrow definition, hereinafter this is repeated no more.

The first working oil path 7 and the second working oil path 8 are connected in main reversing valve 3, as shown in Figure 1, main reversing valve 3 comprises oil inlet P, oil return inlet T, the first actuator port A and the second actuator port B that connects main oil-feed oil circuit 5, main oil return circuit 6, the first working oil path 7 and the second working oil path 8 for correspondence at least.Switching by main reversing valve 3, the first working oil path 7 and the second working oil path 8 are alternately born the function of oil-feed and oil return, namely control by the commutation of main reversing valve 3, when the first working oil path 7 is communicated with main oil-feed oil circuit 5 and the second working oil path 8 when being communicated with main oil return circuit 6, the first working oil path 7 receiving liquid force feed from the main oil-feed oil circuit 5, and rodless cavity 1a or the rod chamber 1b(that hydraulic oil is fed to the first master cylinder 1 decided according to high pressure pumping state and low pressure pumping state), the rodless cavity 2a of the second master cylinder 2 or rod chamber 2b via the second working oil path 8 to main oil return circuit 6 oil returns.When main reversing valve 3 switches to so that the first working oil path 7 is communicated with main oil return circuit 6 that the second working oil path 8 is communicated with main oil-feed oil circuit 5, the oil inlet and oil return process of twin-tub pumping installations is with above-mentioned opposite, thereby realize the alternately flexible of the first and second master cylinders 1,2.Main reversing valve 3 generally can adopt O type three position four-way directional control valve, can certainly adopt the selector valve of other form, and this knows for those skilled in the art.Main reversing valve 3 adopts O type three position four-way directional control valve, when carrying out the high low pressure switching, when main reversing valve 3 is switched to meta when fuel cut-off and oil return, in front continuous working procedure, can be closed with hydraulic oil as the rodless cavity 1a of the first master cylinder 1 of actuator chamber or rodless cavity 2a or the rod chamber 2b of rod chamber 1b and the second master cylinder 2, like this when the switching by high/low pressure cut-over valve, and so that in front continuous working procedure, be interconnected as the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 of actuator chamber or rod chamber 1b and the second master cylinder 2 or rod chamber 2b and during as communicated cavity, can be full of by hydraulic oil in this communicated cavity, with in follow-up pumping procedure as the driving medium in the communicated cavity.

Referring to shown in Figure 1, main reversing valve 3 can adopt the selector valve of various ways, such as solenoid directional control valve, hand-operated direction valve, guide's hyraulic controlled type selector valve etc.For example, main reversing valve 3 among Fig. 1 is guide's hyraulic controlled type O type three position four-way directional control valve, wherein the hydraulic control mouth at main reversing valve 3 two ends is connected to first guide's pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18, this the first guide pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18 are connected in guide's oil-feed oil circuit 15 and guide's oil return circuit 16 via the pilot-actuated valve 14 of selector valve form, switching by pilot-actuated valve 14, can be selectively so that first guide's pilot-controlled working oil circuit 17 be communicated with guide's oil-feed oil circuit 15 and second guide's pilot-controlled working oil circuit 18 is communicated with guide's oil return circuit 16, perhaps so that first guide's pilot-controlled working oil circuit 17 is communicated with guide's oil return circuit 16 and second guide's pilot-controlled working oil circuit 18 is communicated with guide's oil-feed oil circuit 15.The such switching controls by pilot-actuated valve 14 can optionally be fed to guide's hydraulic control oil the one of hydraulic control mouth at the two ends of main reversing valve 3, and another one is then carried out oil return, thereby switches by the commutation that the hydraulic control mode is controlled main reversing valve 3.Pilot-actuated valve 14 can adopt the selector valve of various ways, and it comprises oil inlet P 2, oil return inlet T 2, the first actuator port A2 and the second actuator port B2 that connects guide's oil-feed oil circuit 15, guide's oil return circuit 16, first guide's pilot-controlled working oil circuit 17 and second guide's pilot-controlled working oil circuit 18 for correspondence at least.In Fig. 1, pilot-actuated valve 14 is the 3-position 4-way solenoid directional control valve, the both sides electromagnet YW3 by controlling this 3-position 4-way solenoid directional control valve and YW4 electric or power failure state, can realize easily the commutation of this 3-position 4-way solenoid directional control valve.In addition, guide's oil return circuit 16 generally can be connected to fuel tank or or the main oil return circuit 6(of hydraulic control system its also be connected in fuel tank), because the needed hydraulic control oil oil pressure of pilot control and the equal less of flow, guide's oil-feed oil circuit 15 generally can be connected on the special hydraulic control oil sources, for example on the hydraulic control oil feeding line of the pumping oil circuit of special small-scale liquid press pump or construction machinery hydraulic system, perhaps also can connect branch's oil circuit from main oil-feed oil circuit 5, via or be not connected on this guide's oil-feed oil circuit 15 via reduction valve.In addition, the hydraulic control oil sources that following switching shown in Figure 1 connects with hydraulic control oil-feed oil circuit 10 also is similarly, drives purpose as long as satisfy hydraulic control, and this need not to give unnecessary details for the technician of Hydraulic Field.

As mentioned above, described high/low pressure cut-over valve can adopt the high/low pressure cut-over valve of various known forms.High/low pressure cut-over valve can be connected by oil circuit by the valve that disperses, but more generally be the form that forms combination valve, be to have corresponding interface on the high/low pressure cut-over valve, each interface on this high/low pressure cut-over valve is connected in the first and second master cylinders 1 via corresponding oil circuit respectively, 2 separately

rod chamber

1b, 2b and rodless cavity 1a, the first actuator port A of the interface of 2a and main reversing valve 3 and the second actuator port B.For example, in Fig. 1, described high/low pressure cut-over valve is made of six two-way plug-in valves and switching hydraulic control oil circuit selector valve 9, six two-way plug-in valves are the first two-way plug-in valve C1, the second two-way plug-in valve C2, the 3rd two-way plug-in valve C3, the 4th two-way plug-in valve C4, the 5th two-way plug-in valve C5 and the 6th two-way plug-in valve C6, need to prove, this high/low pressure cut-over valve that is made of with hydraulic control oil circuit selector valve 9 six two-way plug-in valves and corresponding switching belongs to a kind of high/low pressure cut-over valve more common on the engineering machinery, shown its hydraulic connecting theory structure in order to clearly illustrate its high low pressure switching principle among Fig. 1, it does not represent actual mechanical entities linkage structure, this high/low pressure cut-over valve generally forms the form of combination valve in actual the use, each interface on this high/low pressure cut-over valve is connected in the first and second master cylinders 1 via corresponding oil circuit respectively, 2 separately

rod chamber

1b, 2b and rodless cavity 1a, the first actuator port A of the interface of 2a and main reversing valve 3 and the second actuator port B, generally speaking, as long as those skilled in the art are mentioned to the high/low pressure cut-over valve that comprises six two-way plug-in valves, can know clearly its relevant hydraulic connecting relation, for example CN102330665A.

In order to help to understand the handoff procedure of high/low pressure cut-over valve, referring to the hydraulic schematic diagram of high/low pressure cut-over valve shown in Figure 1, describe briefly.Relevant two-way plug-in valve belongs to the known hydraulic element of Hydraulic Field, does not repeat them here.Wherein, the first port of the first two-way plug-in valve C1 is communicated with the rodless cavity 2a of the second master cylinder 2, and the second port is communicated with the rodless cavity 1a of the first master cylinder 1; The first port of the second two-way plug-in valve C2 is communicated with the rod chamber 2b of the second master cylinder 2, and the second port is communicated with the rod chamber 1b of the first master cylinder 1; The first port of the 6th two-way plug-in valve C6 is communicated with the first actuator port A of main reversing valve 3, and the second port is communicated with the rod chamber 1b of the first master cylinder 1; The first port of the 4th two-way plug-in valve C4 is communicated with the first actuator port A of main reversing valve 3, and the second port is communicated with the rodless cavity 1a of the first master cylinder 1; The first port of the 5th two-way plug-in valve C5 is communicated with the second actuator port B of main reversing valve 3, and the second port is communicated with the rod chamber 2b of the second master cylinder 2; The first port of the 3rd two-way plug-in valve C3 is communicated with the second actuator port B of main reversing valve 3, and the second port is communicated with the rodless cavity 2a of the second master cylinder 2.In addition, the hydraulic control mouth of above-mentioned six two-way plug-in valves is connected to and switches the hydraulic control oil circuit, particularly, for example in Fig. 1, switch the hydraulic control oil circuit and comprise the 3-position 4-way solenoid directional control valve that has electromagnet YW1 and YW2 among switching hydraulic control oil circuit selector valve 9(Fig. 1 for both sides, can certainly be the selector valve of other form, two-position four way change valve for example), in above-mentioned six two-way plug-in valves second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is connected in the first actuator port A1 that switches hydraulic control oil circuit selector valve 9 via the first pilot-controlled working oil circuit 12, first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 is connected in the second actuator port B1 that switches hydraulic control oil circuit selector valve 9 via the second pilot-controlled working oil circuit 13, the oil inlet P 1 of this switching hydraulic control oil circuit selector valve 9 is connected in to be switched with hydraulic control oil-feed oil circuit 10, and oil return inlet T 1 is connected in to be switched with hydraulic control oil return circuit 11.

Like this, as shown in Figure 1, when switch hydraulic control oil circuit selector valve 9 by control so that second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is communicated with hydraulic control oil return circuit 11 with switching via the first pilot-controlled working oil circuit 12, and first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 is via the second pilot-controlled working oil circuit 13 and switch and to be communicated with hydraulic control oil-feed oil circuit 10 that (for example the electromagnet YW2 of the 3-position 4-way solenoid directional control valve of the switching of the conduct among Fig. 1 hydraulic control oil circuit selector valve 9 gets electric, and electromagnet YW1 dead electricity), thereby second, the third and fourth two-way plug-in valve C2, C3, C4 be in can bidirectional opening state, and first, the the 5th and the 6th two-way plug-in valve C1, C5, C6 is then owing to the effect locking of hydraulic control oil is closed, in this case, the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is interconnected as communicated cavity, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 then is communicated with the first working oil path 7 and the second working oil path 8 respectively, this moment is by 3 control the first working oil path 7 and alternately oil-feed and the oil returns of the second working oil path 8 of control main reversing valve, thereby so that the first master cylinder 1 and the second master cylinder 2 are alternately flexible, namely be in so-called high pressure pumping state this moment; When switch hydraulic control oil circuit selector valve 9 by control so that second, the third and fourth two-way plug-in valve C2, C3, the hydraulic control mouth of C4 is communicated with hydraulic control oil-feed oil circuit 10 with switching via the first pilot-controlled working oil circuit 12, and first, the the 5th and the 6th two-way plug-in valve C1, C5, the hydraulic control mouth of C6 is via the second pilot-controlled working oil circuit 13 and switch with hydraulic control oil return circuit 11 and be communicated with (the electromagnet YW2 dead electricity of the 3-position 4-way solenoid directional control valve of the switching of the conduct among Fig. 1 hydraulic control oil circuit selector valve 9 for example, and electromagnet YW1 gets electric), thereby second, the third and fourth two-way plug-in valve C2, C3, C4 is locking owing to the effect of hydraulic control oil, and first, the the 5th and the 6th two-way plug-in valve C1, C5, C6 then be in can bidirectional opening state, in this case, the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected as communicated cavity, the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 then is communicated with the first working oil path 7 and the second working oil path 8 respectively, this moment is by 3 control the first working oil path 7 and alternately oil-feed and the oil returns of the second working oil path 8 of control main reversing valve, thereby so that the first master cylinder 1 and the second master cylinder 2 are alternately flexible, namely be in so-called low pressure pumping state this moment.

The typical hydraulic structure of twin-tub pumping installations of the present invention has more than been described, following emphasis is described the unique texture feature of the hydraulic control system of the twin-tub pumping installations that embodies the technology of the present invention design, particularly, hydraulic control system at twin-tub pumping installations of the present invention is under the situation of open type hydraulic system, referring to shown in Figure 1, to above-described similar, the hydraulic control system of described twin-tub pumping installations comprises automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity 1a of the first master cylinder 1 of described twin-tub pumping installations and rodless cavity 2a and the rod chamber 2b of rod chamber 1b and the second master cylinder 2 by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, this first working oil path 7 and the second working oil path 8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 by the main reversing valve 3 of electric control reversing valve form, as key technical feature, hydraulic control system of the present invention also comprises controller, this controller is electrically connected on described main reversing valve 3 and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order, such as operator among Fig. 1 by input device (such as operating grip etc.) so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, control main reversing valve 3 stops the current pumpdown that carries out, and keeps pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after the high low pressure state switches, keep the second predetermined hold-time; The 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

Above-mentioned the first predetermined hold-time and the second predetermined hold-time switch for open hydraulic control system, Closed Hydraulic control system, from high pressure pumping state to low pressure pumping state and switch from low pressure pumping state and high pressure pumping state and have certain differentiation, and this will in more detail description in the controlling method hereinafter.The first predetermined hold-time and the second predetermined hold-time can be determined according to the experience of engineering construction, it is general so that oil circuit has enough oil circuit stabilization time after switching according to the order of sequence, be unlikely again the continuity that too affects pumpdown and get final product, generally can in 1-10s, choose.More preferably, referring to shown in Figure 1, can be provided with for example oil pressure sensor of oil pressure detection device 4(in main oil-feed oil circuit 5, the first working oil path 7 or the second working oil path 8), this oil pressure detection device 4 is electrically connected on controller and is transferred to this controller with the fuel injection pressure signal that will detect, and the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to oil pressure detection device 4 stops moment fuel injection pressure signal and determines the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database.Experts database belongs to a kind of database or the control table of relatively extensively adopting on the engineering mechanical device, it generally determines the corresponding relation of relevant parameter by a large amount of simulated condition tests, thereby after a parameter was determined, controller can be determined the preferred value of other parameter corresponding with this parameter by the inquiry experts database.Particularly, described experts database can be stored in the described controller or external server in, comprise in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value, in this case, because the first predetermined hold-time value and the second predetermined hold-time value all are the more satisfactory measured values by the simulated condition test acquisition of reality, thereby can be so that oil circuit has enough oil circuit stabilization time, the again relatively reliably continuity requirement of balance pumpdown after switching according to the order of sequence.

In addition, be applied at technical conceive of the present invention under the situation of Closed Hydraulic control system, known ground, the Closed Hydraulic control system mainly transfers to realize that by the positive and negative of oil hydraulic pump the oil inlet and oil return of the first working oil path 7 and the second working oil path 8 switches, particularly, in this case, the hydraulic control system of twin-tub pumping installations of the present invention comprises automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity 1a of the first master cylinder 1 of described twin-tub pumping installations and rodless cavity 2a and the rod chamber 2b of rod chamber 1b and the second master cylinder 2 by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path 7 and the second working oil path 8, this first working oil path 7 and the second working oil path 8 are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path 7 by the positive and negative of described oil hydraulic pump, one oil-feed in 8, the another one oil return, similar with above-mentioned open hydraulic control system, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device (being generally motor to control by controller easily) and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, the automatically controlled rotating driving device of controlling described oil hydraulic pump to be stopping the current pumpdown that carries out, and keeps pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and the high low pressure state switches rear second predetermined hold-time that keeps; The 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

It should be noted that at this, because there is not main oil-feed oil circuit (having the repairing oil circuit in the actual hydraulic pressure system) in the Closed Hydraulic control system, therefore, above-mentioned oil pressure detection device 4 can be arranged on the first working oil path 7 or the second working oil path 8, this oil pressure detection device 4 is electrically connected on described controller and is transferred to this controller with the fuel injection pressure signal that will detect, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops moment fuel injection pressure signal and determines described the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database, described experts database is stored in the described controller or in the external server, comprises in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value.

In addition, relevant to the switching controls of controller for the main reversing valve 3 of automatically controlled high/low pressure cut-over valve and electric control reversing valve form, know for those skilled in the art, generally be electromagnet by controlling the respective valve in the automatically controlled high/low pressure cut-over valve and electric control reversing valve both sides electromagnet electric power failure state, and the control spool moves to realize oil circuit control.

In addition, as mentioned above, also be provided with the oil pressure detection device on the main oil-feed oil circuit 1 of the hydraulic control system of twin-tub pumping installations of the present invention, this can judge whether normal operation according to fuel injection pressure signal, thereby so that the service behaviour of twin-tub pumping installations is more reliable, especially when plugging appears in Material pipeline, can detect the rising of unusual oil pressure by this oil pressure detection device, switch thereby can avoid carrying out blindly high low pressure.Further, pumping equipment of the present invention comprises the hydraulic control control system of the twin-tub pumping installations of twin-tub pumping installations and above-mentioned form.

Above with reference to Fig. 1 has described the main structure of twin-tub pumping installations and the high low pressure realized by its hydraulic control system switches hydraulic control process.The high low pressure switching method of twin-tub pumping installations of the present invention is described on the basis of the above.

Referring to Fig. 1, Fig. 2 and shown in Figure 3, as mentioned above, the hydraulic control system of described twin-tub pumping installations comprises main oil-feed oil circuit 5 and main oil return circuit 6, this main oil-feed oil circuit 5 and main oil return circuit 6 generally can be connected in the first and second working oil path 7 via main reversing valve 3,8, with can be so that this first and second working oil path 7,8 alternately are communicated with one and another one in main oil-feed oil circuit 5 and the main oil return circuit 6 simultaneously, thereby so that this first and second working oil path 7,8 alternately oil-feed and oil return (namely so that the first and second working oil path 7, one oil-feed in 8, simultaneously another one oil return), this first and second working oil path 7,8 are respectively applied to the first and second master cylinders 1 of described twin-tub pumping installations, 2 oil inlet and oil return (being that hydraulic oil is carried), thus realize the alternately flexible of this first and second master cylinder 1,2.

The first form of implementation as high low pressure switching method of the present invention, it is mainly used in the twin-tub pumping installations is switched to low pressure pumping state from high pressure pumping state, particularly, the high low pressure switching method of the twin-tub pumping installations of this first form of implementation comprises the steps:

First, be under the state of high pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path 7,8 all end (namely so that the first and second working oil path stop the conveying liquid force feed) with described main oil-feed oil circuit 5 and main oil return circuit 6, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure;

The second, so that described the first and second master cylinders 1,2 rodless cavity 1a separately, 2a is interconnected to form communicated cavity, and so that this communicated cavity all end with respect to described the first and second working oil path 7,8; And so that the rod chamber 2b of the rod chamber 1b of described the first master cylinder 1 and described the second master cylinder 2 relative to each other end, and so that the rod chamber 1b of described the first master cylinder 1 is communicated with described the first working oil path 7, the rod chamber 2b of described the second master cylinder 2 is communicated with described the second working oil path 8, thereby so that described twin-tub pumping installations is in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness;

The 3rd, so that described the first and second working oil path 7,8 alternately are communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6, namely realize alternately oil-feed and oil return, thereby by the first and second working oil path 7,8 so that alternately oil-feed and the oil return of rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2, thereby so that described twin-tub pumping installations is in low pressure pumping job state.

In the form of implementation of above-mentioned high low pressure switching method, it will be appreciated that, the present invention is above-mentioned so that the twin-tub pumping installations is to realize a kind of time-oriented sequential control from the high low pressure switching method key that high pressure pumping state switches to low pressure pumping state, namely so that stop the high pressure pumping, the low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in the prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by after each operating procedure, keeping certain buffer time (for example the first scheduled delay ta and the second scheduled delay tb), so that the oil circuit of hydraulic control system carries out next step operation after stablizing again, this has alleviated the hydraulic shock in the hydraulic control system effectively, so that master cylinder stable working, and keep relative stablizing so that switch the hydraulic oil of the communicated cavity inner sealing that forms in handoff procedure, thereby relative efficiency ground keeps constant so that master cylinder drives stroke.It should be noted that at this, in fact in above-mentioned high low pressure switching method of the present invention, the time-oriented sequential control that has realized according to the order of sequence priority of each step, therefore above-mentioned the first scheduled delay ta and the second scheduled delay tb can be included as zero situation, typically, described the first scheduled delay ta and the second scheduled delay tb can be respectively 0-10s.

About determining of described the first scheduled delay ta and the second scheduled delay tb, more preferably, as indicated above, hydraulic control system at described twin-tub pumping installations is under the situation of open hydraulic control system, described the first and second working oil path 7,8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3, in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit 5, high pressure pumping on the first working oil path 7 or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the above-mentioned first step and the second scheduled delay tb in the described second step by the inquiry experts database.As another kind of situation, hydraulic control system at described twin-tub pumping installations is under the situation of Closed Hydraulic control system, described the first and second working oil path 7,8 are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path 7 by the positive and negative of described oil hydraulic pump, one oil-feed in 8, the another one oil return, in above-mentioned first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect high pressure pumping on described the first working oil path 7 or the second working oil path and stop constantly oil pressure, and stop oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the described first step and the second scheduled delay tb in the described second step by the inquiry experts database.Comprise in the described experts database that each high pressure pumping stops constantly corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value, that is to say that this first scheduled delay ta and the second scheduled delay tb are that above-mentioned hydraulic control system adopts corresponding the first predetermined hold-time and the second predetermined hold-time the control procedure that is sent to low pressure pumping switching from high-pressure service pump.

Typically, described the first and second working oil path 7,8 are connected in described the first and second master cylinders 1,2 via high/low pressure cut-over valve respectively, in above-mentioned second step, by the switching of described high/low pressure cut-over valve so that described twin-tub pumping installations is in described low pressure pumping readiness.But it should be noted that at this switching of above-mentioned second step do not adopt the form of high/low pressure cut-over valve to realize certainly, the same mode that is communicated with sebific duct by the manual change that exists realizes in the prior art.Referring to shown in Figure 1, for example, as a kind of common type, the switching hydraulic control oil circuit selector valve 9(that described high/low pressure cut-over valve can comprise six two-way plug-in valve C1, C2, C3, C4, C5, C6 and be used for these six two-way plug-in valve on off operating modes of control for example Fig. 1 should switch hydraulic control oil circuit selector valve 9 employing O type 3-position 4-way solenoid directional control valves, this typical high/low pressure cut-over valve form is above being described, and does not repeat them here).

Typically, the hydraulic control system of described twin-tub pumping installations can be the open hydraulic control system, and as mentioned above, wherein said the first working oil path 7 and the second working oil path 8 are connected in described main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3.In above-mentioned first step, by controlling described main reversing valve 3 so that described the first and second working oil path 7,8 all end with main oil-feed oil circuit 5 and main oil return circuit 6; In above-mentioned third step, by controlling described main reversing valve 3 so that described the first and second working oil path 7,8 alternately be communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6.For example, main reversing valve 3 can adopt hyraulic controlled type O type three position four-way directional control valve shown in Figure 1, should

Referring to Fig. 1, Fig. 2 and Fig. 4, as the another kind of form of implementation of high low pressure switching method of the present invention, its low pressure pump that is mainly used in the twin-tub pumping installations is sent to the high pressure pumping and switches, and particularly, the high low pressure switching method of this another kind form of implementation comprises the steps:

First, be under the state of low pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path 7,8 all end (namely so that the first and second working oil path stop the conveying liquid force feed) with described main oil-feed oil circuit 5 and main oil return circuit 6, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping;

The second, so that described the first and second master cylinders 1,2 rod chamber 1b separately, 2b is interconnected to form communicated cavity, and so that this communicated cavity with respect to described the first and second working oil path 7,8) all the cut-off; And so that the rodless cavity 2a of the rodless cavity 1a of described the first master cylinder and described the second master cylinder relative to each other end, and so that the rodless cavity 1a of this first master cylinder is communicated with described the first working oil path 7, the rodless cavity 2a of this second master cylinder is communicated with described the second working oil path 8, thereby so that described twin-tub pumping installations is in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness;

The 3rd, so that described the first and second working oil path 7,8 alternately are communicated with one and the another one of described main oil-feed oil circuit 5 and main oil return circuit 6, thereby by the first and second working oil path 7,8 so that alternately oil-feed and oil return of the rodless cavity 2a of the rodless cavity 1a of described the first master cylinder and the second master cylinder, thereby so that described twin-tub pumping installations is in high pressure pumping job state.

Similar with above-mentioned form of implementation of the present invention, in the another kind of form of implementation of this high low pressure switching method, the present invention is above-mentioned so that the twin-tub pumping installations also is to realize a kind of time-oriented sequential control from the high low pressure switching method key that low pressure pumping state switches to high pressure pumping state, namely so that stop the low pressure pumping, the high pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in the prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by after each operating procedure, keeping certain buffer time (for example the first scheduled time ta ' and the second scheduled time tb '), so that the oil circuit of hydraulic control system carries out next step operation after stablizing again, this has alleviated the hydraulic shock in the hydraulic control system effectively, so that master cylinder stable working, and the hydraulic oil of having realized the communicated cavity inner sealing is relatively stable in different handoff procedures, thereby relative efficiency ground keeps constant so that master cylinder drives stroke.Similarly, in the above-mentioned high low pressure switching method of the present invention, the time-oriented sequential control that has realized according to the order of sequence priority of each step, therefore above-mentioned the first scheduled time ta ' and the second scheduled time tb ' can be included as zero situation, typically, described the first scheduled time ta ' and the second scheduled time tb ' can be respectively 0-10s.

About determining of the first scheduled time ta ' and the second scheduled time tb ', more preferably, hydraulic control system at described twin-tub pumping installations is under the situation of open hydraulic control system, wherein said the first and second working oil path 7,8 are connected in main oil-feed oil circuit 5 and main oil return circuit 6 via main reversing valve 3, in above-mentioned first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit 5, low pressure pumping on the first working oil path 7 or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database; Perhaps the hydraulic control system at described twin-tub pumping installations is under the situation of Closed Hydraulic control system, wherein said the first and second working oil path 7,8 are connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path 7 by the positive and negative of described oil hydraulic pump, one oil-feed in 8, the another one oil return, in above-mentioned first step, the low pressure pumping that detects when stopping the low pressure pumpdown of described twin-tub pumping installations on described the first working oil path 7 or the second working oil path stops constantly oil pressure, and stop oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database, comprise in the described experts database that each low pressure pumping stops the moment corresponding the first scheduled time value of oil pressure value and the second scheduled time value.That is to say, this first scheduled time ta ' and the second scheduled time tb ' be corresponding the first predetermined hold-time and the second predetermined hold-time of employing the control procedure that is sent to high pressure pumping switching from low pressure pump for above-mentioned open type or Closed Hydraulic control system accordingly, and this all can be by the simulated condition test so that experts database be set up corresponding data corresponding relation pointedly for the different handoff procedures of the hydraulic control system of different types.

In addition, realize high pressure pumping readiness and replace the state switchings such as oil inlet and oil return by main reversing valve 3 realizations the first and second working oil path 7,8 about passing through the just switching of switching valve, similar with above-mentioned form of implementation, do not repeat them here.

The high low pressure switching method of the twin-tub pumping installations of above-mentioned first and second kinds of forms of implementation can be applicable to the high low pressure switching controls of various known twin-tub pumping installations at large, especially is applicable to the high low pressure switching controls that the Concrete Double cylinder pump send device (those skilled in the art are also referred to as " concrete pump ").

For helping those skilled in the art to understand the high low pressure switching method of above-mentioned two kinds of forms of the present invention, below take the twin-tub pumping installations of a kind of canonical form of Fig. 1 and hydraulic control system is described high low pressure switching method of the present invention as example specific operation process thereof.In Fig. 1, main reversing valve 3 is hyraulic controlled type O type three position four-way directional control valve, and its hydraulic control linkage structure is namely controlled guide's hydraulic control oil circuits to realize the selector valve of main reversing valve 3 by the pilot-actuated valve 14 of 3-position 4-way solenoid directional control valve form hereinbefore to be described; High/low pressure cut-over valve adopts the canonical form that comprises six two-way plug-in valves, and the hydraulic control oil circuit of these six two-way plug-in valves is controlled by the switching hydraulic control oil circuit selector valve 9 of 3-position 4-way solenoid directional control valve form.Fig. 2 is that twin-tub pumping installations shown in Figure 1 is realized the sequential chart that high low pressure switches.Referring to illustrated in figures 1 and 2, t0 to t1 constantly the twin-tub pumping installations be high pressure pumping job state, the right side electromagnet YW2 that switches hydraulic control oil circuit selector valve 9 this moment gets electric, left side electromagnet YW1 dead electricity; Main reversing valve 3 makes winner's oil-feed oil circuit 5 and main oil return circuit 6 alternately be communicated with the first working oil path 7 and the second working oil path 8 under the normal control of pilot-actuated valve 14.At t1 constantly, by control pilot-actuated valve 14 and so that main reversing valve 3 switches to meta, be electromagnet YW3, the YW4 dead electricity of pilot-actuated valve 14 both sides, main reversing valve 3 switches back meta, the high pressure pumpdown stops, and delays time to the t2 moment (being the first above-mentioned scheduled delay ta=t2-t1).At t2 constantly, so that switch the right side electromagnet YW2 dead electricity of hydraulic control oil circuit selector valve 9, two-way plug-in valve C1, C5, C6 opens, simultaneously so that the left side electromagnet YW1 of switching hydraulic control oil circuit selector valve 9 gets electric, two-way plug-in valve C2, C3, C4 closes, thereby the first working oil path 7 is communicated with the rod chamber 1b of the first master cylinder 1, the second working oil path 8 is communicated with the rod chamber 2b of the second master cylinder 2, and the rodless cavity 2a of the rodless cavity 1a of the first master cylinder 1 and the second master cylinder 2 is interconnected, and all with respect to the first working oil path 7 and 8 cut-offs of the second working oil path, thereby so that the twin-tub pumping installations switches to low pressure pumping readiness, downward up to the t3 moment (being above-mentioned the second scheduled delay tb=t3-t2) at this low pressure pumping state.At t3 constantly, by so that both sides electromagnet YW3, the YW4 of pilot-actuated valve 14 replace electricly, thereby so that main reversing valve 3 alternately is operated in left position and right, the twin-tub pumping installations carries out the low pressure pumpdown.In addition, under the situation that is sent to high pressure pumping switching from low pressure pump, referring to Fig. 1 and Fig. 2, in the t1 ' moment before, the twin-tub pumping installations is low pressure pumping job state, and switch the right side electromagnet YW2 dead electricity of hydraulic control oil circuit selector valve 9 this moment, and left side electromagnet YW1 gets electric; Main reversing valve 3 makes winner's oil-feed oil circuit 5 and main oil return circuit 6 alternately be communicated with the first working oil path 7 and the second working oil path 8 under the normal control of pilot-actuated valve 14.At t1 ' constantly, by control pilot-actuated valve 14 and so that main reversing valve 3 switches to meta, be electromagnet YW3, the YW4 dead electricity of pilot-actuated valve 14 both sides, main reversing valve 3 switches back meta, the low pressure pumpdown stops, and delays time to t2 ' constantly (being first above-mentioned scheduled time ta '=t2 '-t1 ').At t2 ' constantly, get electric so that switch the right side electromagnet YW2 of hydraulic control oil circuit selector valve 9, two-way plug-in valve C1, C5, the C6 locking, simultaneously so that switch the left side electromagnet YW1 dead electricity of hydraulic control oil circuit selector valve 9, two-way plug-in valve C2, C3, C4 opens, thereby the first working oil path 7 is communicated with the rodless cavity 1a of the first master cylinder 1, the second working oil path 8 is communicated with the rodless cavity 2a of the second master cylinder 2, and the rod chamber 2b of the rod chamber 1b of the first master cylinder 1 and the second master cylinder 2 is interconnected, and all with respect to the first working oil path 7 and 8 cut-offs of the second working oil path, thereby so that the twin-tub pumping installations switches to high pressure pumping readiness, downward up to t3 ' constantly (being above-mentioned second scheduled time tb '=t3 '-t2 ') at this high pressure pumping state.At t3 ' constantly, by so that both sides electromagnet YW3, the YW4 of pilot-actuated valve 14 replace electricly, thereby so that main reversing valve 3 alternately is operated in left position and right, the twin-tub pumping installations carries out the high pressure pumpdown.

Need to prove at this; high low pressure switching method of the present invention is not limited to the twin-tub pumping installations shown in Fig. 1 and the concrete form of hydraulic control system thereof; there are various forms in the prior art in described high/low pressure cut-over valve, main reversing valve 3 etc.; no matter it adopts automatically controlled, hydraulic control, electric-hydraulic proportion control; or adopt manually control etc.; as long as it adopted the technical conceive of time-oriented sequential control of the present invention, it all belongs to protection scope of the present invention.In addition; the above-mentioned open type hydraulic system of realizing the first working oil path 7 and 8 commutations of the second working oil path take main reversing valve 3 is described as example; but the present invention is not limited thereto; for example high low pressure switching method of the present invention equally also is applicable to turn to realize the closed system that commutates by changing oil hydraulic pump; in this case; the first working oil path 7 of twin-tub pumping installations and the second working oil path 8 form closed circuit via oil hydraulic pump; above-mentioned main oil-feed oil circuit and main oil return circuit can no longer arrange (considers leakage in the practical application; the factors such as sealing; oil hydraulic pump also is connected with corresponding repairing oil circuit); in this case; during 7 oil-feed of the first working oil path; backhaul hydraulic oil on 8 oil returns of the second working oil path and the second working oil path 8 is delivered directly on the first working oil path 7 via oil hydraulic pump; when the oil hydraulic pump change turns to; 7 oil returns of the first working oil path; backhaul hydraulic oil on 8 oil-feeds of the second working oil path and the first working oil path 7 is delivered directly on the second working oil path 8 via oil hydraulic pump; thereby alternately so that the one oil-feed of the first working oil path 7 and the second working oil path 8; simultaneously another one oil return; thereby realize the alternately flexible of the first master cylinder 1 and the second master cylinder 2, these all belong to protection scope of the present invention.

Can be found out by upper description, the invention has the advantages that: high low pressure switching method of the present invention with respect to existing techniques in realizing accurate time-oriented sequential control, namely so that stop pumping, the high low pressure handover operation, and restart pumpdown and carry out according to predetermined sequential, this has been avoided in the prior art when high low pressure switches simultaneously or has carried out disorderly a plurality of control actions, and by after corresponding operating procedure, keeping certain buffer time, so that the oil circuit of hydraulic control system carries out next step operation after stablizing again, this has alleviated the hydraulic shock in the hydraulic control system effectively, so that master cylinder stable working, and the hydraulic oil in handoff procedure so that in the communicated cavity is relatively stable, thereby relative efficiency ground keeps constant so that master cylinder drives stroke.The high low pressure that high low pressure switching method of the present invention can be applied to the twin-tub pumping installations of various existing forms at large switches, and it has general applicability and using value, and especially it can adopt automatically controlled form, thereby realizes automatically control.

Especially, when the hydraulic control system of twin-tub pumping installations adopts automatically controlled switch forms (for example illustrative hydraulic control system of Fig. 1), high low pressure switching method of the present invention can be realized time-oriented sequential control mechanical, electrical, the liquid one easily, and intelligence is convenient.That is to say, the present invention is according to the practical situation of the hydraulic system in the twin-tub pumping installations high low pressure handoff procedure, reasonably control the sequential of cycle and taking corresponding operation in the high low pressure handoff procedure, at first pumping stops and delaying time, carrying out high low pressure switches again, restart pumping after to be switched the finishing, thereby so that the hydraulic control system handoff procedure is relatively steadily reliable.

Below describe by reference to the accompanying drawings preferred implementation of the present invention in detail; but; the present invention is not limited to the detail in the above-mentioned mode of execution; in technical conceive scope of the present invention; can carry out multiple simple variant to technological scheme of the present invention, these simple variant all belong to protection scope of the present invention.

Need to prove that in addition each the concrete technical characteristics described in above-mentioned embodiment in reconcilable situation, can make up by any suitable mode.For fear of unnecessary repetition, the present invention is to the no longer separately explanation of various possible compound modes.

In addition, also can carry out combination in any between the various mode of execution of the present invention, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.

Claims

1. the high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second master cylinders (1 that are respectively applied to this twin-tub pumping installations, 2) the first and second working oil path (7 of oil inlet and oil return, 8), this alternately oil-feed and oil return of the first and second working oil path (7,8), to realize described the first and second master cylinders (1, alternately stretching 2), wherein, described high low pressure switching method comprises the steps:

First, be under the state of high pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path (7,8) stop the conveying liquid force feed, to stop the high pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of high pressure pumping, and keep the first scheduled delay ta at the to be switched state of this high pressure pumping;

The second so that described the first and second master cylinders (1,2) rodless cavity (1a, 2a) separately is interconnected to form communicated cavity, and so that this communicated cavity all end with respect to described the first and second working oil path (7,8); And so that the rod chamber (2b) of the rod chamber of described the first master cylinder (1b) and described the second master cylinder relative to each other end, and so that the rod chamber of this first master cylinder (1b) is communicated with described the first working oil path (7), the rod chamber of this second master cylinder (2b) is communicated with described the second working oil path (8), thereby so that described twin-tub pumping installations is in low pressure pumping readiness, and keep the second scheduled delay tb at this low pressure pumping readiness;

The 3rd, by described the first and second working oil path (7,8) so that alternately oil-feed and the oil return of rod chamber (2b) of the rod chamber of described the first master cylinder (1b) and the second master cylinder, thereby so that described twin-tub pumping installations is in low pressure pumping job state.

2. high low pressure switching method according to claim 1, wherein, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path (7,8) be connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3), in described first step, when stopping the high pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit (5), high pressure pumping on the first working oil path (7) or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the described first step and the second scheduled delay tb in the described second step by the inquiry experts database; Perhaps

The hydraulic control system of described twin-tub pumping installations is the Closed Hydraulic control system, wherein said the first and second working oil path (7,8) be connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path (7 by the positive and negative of described oil hydraulic pump, 8) the one oil-feed in, the another one oil return, in described first step, the high pressure pumping that detects when stopping the high pressure pumpdown of described twin-tub pumping installations on described the first working oil path (7) or the second working oil path stops constantly oil pressure, and stop oil pressure constantly according to this high pressure pumping and determine the first scheduled delay ta in the described first step and the second scheduled delay tb in the described second step by the inquiry experts database

Comprise in the described experts database that each high pressure pumping stops constantly corresponding the first scheduled delay value of oil pressure value and the second scheduled delay value.

3. high low pressure switching method according to claim 1, wherein, described the first scheduled delay ta and the second scheduled delay tb are respectively 0-10s.

4. high low pressure switching method according to claim 1, wherein, described the first and second working oil path (7,8) be connected in described the first and second master cylinders (1 via high/low pressure cut-over valve respectively, 2), in described second step, by the switching of described high/low pressure cut-over valve so that described twin-tub pumping installations is in described low pressure pumping readiness.

5. high low pressure switching method according to claim 1, wherein, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path (7,8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3); In described first step, by controlling described main reversing valve (3) so that described the first and second working oil path (7,8) all end with described main oil-feed oil circuit (5) and main oil return circuit (6), thereby so that this first and second working oil path (7,8) stops the conveying liquid force feed; In described third step, by controlling described main reversing valve (3) so that described the first and second working oil path (7,8) alternately with described main oil-feed oil circuit (5) and main oil return circuit) one and the another one of (6) be communicated with, thereby by described the first and second working oil path (7,8) so that alternately oil-feed and the oil return of rod chamber (2b) of the rod chamber of described the first master cylinder (1b) and the second master cylinder.

6. high low pressure switching method according to claim 5, wherein, described main reversing valve (3) is O type three position four-way directional control valve.

7. each described high low pressure switching method in 6 according to claim 1, wherein, described twin-tub pumping installations is that the Concrete Double cylinder pump send device.

8. the high low pressure switching method of twin-tub pumping installations, the hydraulic control system of described twin-tub pumping installations comprises the first and second master cylinders (1 that are respectively applied to this twin-tub pumping installations, 2) the first and second working oil path (7 of oil inlet and oil return, 8), this alternately oil-feed and oil return of the first and second working oil path (7,8), to realize described the first and second master cylinders (1, alternately stretching 2), wherein, described high low pressure switching method comprises the steps:

First, be under the state of low pressure pumpdown at described twin-tub pumping installations, so that described the first and second working oil path (7,8) stop the conveying liquid force feed, to stop the low pressure pumpdown of described twin-tub pumping installations, thereby so that this twin-tub pumping installations is in the to be switched state of low pressure pumping, and keep the first scheduled time ta ' at the to be switched state of this low pressure pumping;

The second so that described the first and second master cylinders (1,2) rod chamber (1b, 2b) separately is interconnected to form communicated cavity, and so that this communicated cavity all end with respect to described the first and second working oil path (7,8); And so that the rodless cavity (2a) of the rodless cavity of described the first master cylinder (1a) and described the second master cylinder relative to each other end, and so that the rodless cavity of this first master cylinder (1a) is communicated with described the first working oil path (7), the rodless cavity of this second master cylinder (2a) is communicated with described the second working oil path (8), thereby so that described twin-tub pumping installations is in high pressure pumping readiness, and keep the second scheduled time tb ' at this high pressure pumping readiness;

The 3rd, by described the first and second working oil path (7,8) so that alternately oil-feed and the oil return of rodless cavity (2a) of the rodless cavity of described the first master cylinder (1a) and the second master cylinder, thereby so that described twin-tub pumping installations is in high pressure pumping job state.

9. high low pressure switching method according to claim 8, wherein, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path (7,8) be connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3), in described first step, when stopping the low pressure pumpdown of described twin-tub pumping installations, detect described main oil-feed oil circuit (5), low pressure pumping on the first working oil path (7) or the second working oil path stops constantly oil pressure, and stops oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database; Perhaps

The hydraulic control system of described twin-tub pumping installations is the Closed Hydraulic control system, wherein said the first and second working oil path (7,8) be connected to the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path (7 by the positive and negative of described oil hydraulic pump, 8) the one oil-feed in, the another one oil return, in described first step, the low pressure pumping that detects when stopping the low pressure pumpdown of described twin-tub pumping installations on described the first working oil path (7) or the second working oil path stops constantly oil pressure, and stop oil pressure constantly according to this low pressure pumping and determine the first scheduled time ta ' in the described first step and the second scheduled time tb ' in the described second step by the inquiry experts database

Comprise in the described experts database that each low pressure pumping stops constantly corresponding the first scheduled time value of oil pressure value and the second scheduled time value.

10. high low pressure switching method according to claim 8, wherein, described the first scheduled time ta ' and the second scheduled time tb ' are respectively 0-10s.

11. high low pressure switching method according to claim 8, wherein, described the first and second working oil path (7,8) be connected in described the first and second master cylinders (1 via high/low pressure cut-over valve respectively, 2), in described second step, by the switching of described high/low pressure cut-over valve so that described twin-tub pumping installations is in described high pressure pumping readiness.

12. high low pressure switching method according to claim 8, wherein, the hydraulic control system of described twin-tub pumping installations is the open hydraulic control system, wherein said the first and second working oil path (7,8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) via main reversing valve (3); In described first step, by controlling described main reversing valve (3) so that described the first and second working oil path (7,8) all end with described main oil-feed oil circuit (5) and main oil return circuit (6), thereby so that this first and second working oil path (7,8) stops the conveying liquid force feed; In described third step, by controlling described main reversing valve (3) so that described the first and second working oil path (7,8) alternately with described main oil-feed oil circuit (5) and main oil return circuit) one and the another one of (6) be communicated with, thereby by described the first and second working oil path (7,8) so that alternately oil-feed and the oil return of rodless cavity (2a) of the rodless cavity of described the first master cylinder (1a) and the second master cylinder.

13. high low pressure switching method according to claim 12, wherein, described main reversing valve (3) is O type three position four-way directional control valve.

14. each described high low pressure switching method in 13 according to claim 8, wherein, described twin-tub pumping installations is that the Concrete Double cylinder pump send device.

15. the hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity (1a) of the first master cylinder (1) of described twin-tub pumping installations and rodless cavity (2a) and the rod chamber (2b) of rod chamber (1b) and the second master cylinder (2) by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path (7) and the second working oil path (8), this first working oil path (7) and the second working oil path (8) are connected in main oil-feed oil circuit (5) and main oil return circuit (6) by the main reversing valve (3) of electric control reversing valve form, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on described main reversing valve (3) and automatically controlled high/low pressure cut-over valve, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, control described main reversing valve (3) and stop the current pumpdown that carries out, and keep pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and after the high low pressure state switches, keep the second predetermined hold-time; The 3rd, control described main reversing valve so that described twin-tub pumping installations carries out pumpdown.

16. the hydraulic control system of twin-tub pumping installations according to claim 15, wherein, described main oil-feed oil circuit (5), be provided with oil pressure detection device (4) on the first working oil path (7) or the second working oil path (8), this oil pressure detection device (4) is electrically connected on described controller and is transferred to this controller with the fuel injection pressure signal that will detect, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops moment fuel injection pressure signal and determines described the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database, described experts database is stored in the described controller or in the external server, comprises in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value.

17. the hydraulic control system of twin-tub pumping installations, comprise automatically controlled high/low pressure cut-over valve, this automatically controlled high/low pressure cut-over valve is connected in the rodless cavity (1a) of the first master cylinder (1) of described twin-tub pumping installations and rodless cavity (2a) and the rod chamber (2b) of rod chamber (1b) and the second master cylinder (2) by pipeline, described automatically controlled high/low pressure cut-over valve is connected in the first working oil path (7) and the second working oil path (8), this first working oil path (7) and the second working oil path (8) are connected in the first hydraulic fluid port and second hydraulic fluid port of oil hydraulic pump, to transfer so that described the first and second working oil path (7 by the positive and negative of described oil hydraulic pump, 8) the one oil-feed in, the another one oil return, wherein, described hydraulic control system also comprises controller, this controller is electrically connected on automatically controlled rotating driving device and the automatically controlled high/low pressure cut-over valve of described oil hydraulic pump, described controller is used for receiving operational order so that described twin-tub pumping installations is switched to the low pressure pumping or switches to the high pressure pumping from the low pressure pumping from the high pressure pumping, and this controller is controlled according to following sequential: first, the automatically controlled rotating driving device of controlling described oil hydraulic pump to be stopping the current pumpdown that carries out, and keeps pumpdown halted state the first predetermined hold-time; The second, control described automatically controlled high/low pressure cut-over valve and carry out required high low pressure switching, and the high low pressure state switches rear second predetermined hold-time that keeps; The 3rd, control the automatically controlled rotary actuation of described oil hydraulic pump so that described twin-tub pumping installations carries out pumpdown.

18. the hydraulic control system of twin-tub pumping installations according to claim 17, wherein, be provided with oil pressure detection device (4) on described the first working oil path (7) or the second working oil path (8), this oil pressure detection device (4) is electrically connected on described controller and is transferred to this controller with the fuel injection pressure signal that will detect, the pumping that described controller detects when described twin-tub pumping installations stops current pumpdown according to described oil pressure detection device stops moment fuel injection pressure signal and determines described the first predetermined hold-time and the second predetermined hold-time by the inquiry experts database, described experts database is stored in the described controller or in the external server, comprises in this experts database that each pumping stops constantly corresponding the first predetermined hold-time value and the second predetermined hold-time value of oil pressure value.

19. pumping equipment comprises the hydraulic control system of twin-tub pumping installations and this twin-tub pumping installations, wherein, described hydraulic control system is each described hydraulic control system in 18 according to claim 15.