CN201428657Y - Hydraulic control valve and telescopic boom control system with same - Google Patents

Abstract

The utility model discloses a hydraulic control valve, the valve body of which is provided with a first hydraulic fluid port, a second hydraulic fluid port, a third hydraulic fluid port and a fourth hydraulic fluid port. The control valve has two working conditions that: in the first working condition, an oil line between the first and the third hydraulic fluid ports are communicated, when the liquid inlet pressure of the second hydraulic fluid port is larger than a preset value, the oil line from the fourth hydraulic fluid port to the second hydraulic fluid port is communicated; and in the second working condition, the oil line between the first and the fourth hydraulic fluid ports is communicated. Preferably, when in the second working condition, the oil line between the second and the third hydraulic fluid ports is not communicated. The utility model has unique control principle, can control the oil line between the fourth and the second hydraulic fluid ports to be communicated by adjusting the pressure, thereby having the advantages of stable controls parameters and reliable operation. On the basis of the hydraulic control valve, the utility model further provides a telescopicboom control system with the hydraulic control valve.

Description

Hydraulic control valve and have the telescopic boom control system of this valve

Technical field

The utility model relates to hydraulic transmission technology, is specifically related to a kind of hydraulic control valve and has the telescopic boom control system of this valve.

Background technique

At present, the extending means of crane telescopic formula jib has dual mode: oil cylinder adds rope row's formula extending means and the full-automatic extending means of single cylinder bolt-type.Compare with the single cylinder bolt-type extending means, oil cylinder adds rope row formula extending means and has the high advantage of flexible efficient, and can stretch to any position in theory.For four joints and the above telescopic arm support of four joints, generally adopt the two-stage cylinder to add rope row formula extending means, wherein, the one-level telescopic cylinder is used to control the flexible of two joint arms, and the secondary telescopic cylinder is used to control three joint arms and flexible with the upper arm joint thereof.Referring to Fig. 1, the figure shows the working principle that existing twin-tub adds rope row formula extending means control system.

The correct job order that existing twin-tub adds rope row formula extending means is: during semi-girder, stretch out the one-level telescopic cylinder earlier and stretch out the secondary telescopic cylinder again; When contracting arm, regain the secondary telescopic cylinder earlier and regain the one-level telescopic cylinder again.Yet, the user in actual mechanical process, such as, three, four joint arms are keeped in repair or maintain operation, need to regain the one-level telescopic cylinder earlier so that the operation that the operating personnel is correlated with, this kind operating mode tends to cause the distortion of core canal curvature, makes that oil cylinder can't proper functioning.As shown in Figure 1, if regain the one-level telescopic cylinder when the secondary telescopic cylinder is unrecovered, the pressure oil fuel feeding is given one-level telescopic cylinder rod chamber, realizes the withdrawal of one-level telescopic cylinder; Because one-level telescopic cylinder rod chamber communicates with secondary telescopic cylinder rod chamber, the pressure oil of secondary telescopic cylinder rod chamber promotes secondary telescopic cylinder retraction, and the oil in the secondary telescopic cylinder rodless cavity enters the core tube chamber.In addition, the flexible external one-way throttle valve of switching valve, the damping size of this one-way throttle valve must be mated with system requirements, otherwise will cause the secondary telescopic cylinder overhanging.

Referring to Fig. 2, this figure is the overall structure sectional view of existing one-level telescopic cylinder.Shown in the figure, core pipe 30 is a simply supported beam, and an end is welded on cylinder head 40, and the other end inserts pipe box 20 inside, constitutes core pipe oil circuit, and pipe box 20 1 ends are welded on cylinder tail 10, one ends and cooperate with core pipe 30.When one-level telescopic cylinder retraction, when core pipe 30 inserts in the pipe box 20, core pipe 30 inner volumes are dwindled.In this process, the effective volume elastic modulus E of medium in the core pipe _σWith its volume variable Δ V _σBetween relation as shown in the formula:

$E_{\mathrm{\σ}}=\frac{V_{\mathrm{to}}\mathrm{\Δp}}{\mathrm{\Δ}{V}_{\mathrm{\σ}}}$

Wherein, E _σBe the effective volume Young's modulus, Δ V _σBe volume variable, V _ToBe initial volume, Δ p is a pressure increment.Because E _σBe definite value, core pipe inner volume is dwindled and is caused Δ V _σIncrease rapidly, the core tube chamber is a booster cavity, produces bigger Δ p, and Δ p acts on the ring cross-section of core pipe, when the amount of deflection of this active force greater than core pipe simply supported beam, then can produce the problem of core canal curvature distortion.

Above-mentioned analysis as can be known, the damping size of aforementioned one-way throttle valve is crucial Control Parameter.Yet the damping of throttle valve size can change according to the variation of systematic environment, such as, system temperature is too high, the factors such as impurity in the working medium, and the damping meeting of this throttle valve departs from setting in advance.Therefore, the dredge oil amount that adopts throttle valve to adjust the core tube chamber can't satisfy controls requirement accurately, has the hidden danger of core canal curvature distortion.

In view of this, demand urgently being optimized design, develop a kind of hydraulic control valve that prevents telescopic oil cylinder core canal curvature at the control technique of two-stage oil hydraulic cylinder.

The model utility content

At above-mentioned defective, the technical problem that the utility model solves is, a kind of hydraulic control valve is provided, and when guaranteeing that the one-level telescopic cylinder is not regained by the proper functioning order, can not produce the phenomenon of core canal curvature.On this basis, the utility model also provides a kind of telescopic boom control system with this valve.

The hydraulic control valve that the utility model provides, its valve body have first hydraulic fluid port, second hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port; This control valve has two working staties: in first working state, its first hydraulic fluid port is communicated with oil circuit between the 3rd hydraulic fluid port, and the inlet hydraulic of its second hydraulic fluid port is during greater than predefined value, the oil circuit conducting of the 4th hydraulic fluid port to the second hydraulic fluid port; In second working state, its first hydraulic fluid port is communicated with oil circuit between the 4th hydraulic fluid port.

Preferably, in second working state, the non-connection of oil circuit between its second hydraulic fluid port and the 3rd hydraulic fluid port.

Preferably, described valve body is integrated with first selector valve and relief valve; Described first selector valve has four hydraulic fluid ports: its first hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port are communicated with first hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port of valve body respectively, and its second hydraulic fluid port is communicated with the filler opening of described relief valve; The oil outlet of described relief valve is communicated with second hydraulic fluid port of described valve body; Described first selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port is non-; The inlet hydraulic of the 4th hydraulic fluid port of described valve body is during greater than the adjusting pressure set points of described relief valve, and the 4th hydraulic fluid port of described first selector valve and second hydraulic fluid port of valve body are communicated with.

Preferably, described first selector valve is the two-position four-way pilot operated directional control valve; When control fluid acted on the spring chamber of described two-position four-way pilot operated directional control valve, this valve was in first working position; When control fluid acted on the non-spring chamber of described hydraulic control two-position four way change valve, this valve was in second working position.

Preferably, also have the 5th hydraulic fluid port that is used for being communicated with and the 6th hydraulic fluid port that is used for being communicated with on the described valve body with the pilot pressure oil circuit with oil return circuit; And described valve body also is integrated with second selector valve, first hydraulic fluid port of described second selector valve and second hydraulic fluid port are communicated with the 5th hydraulic fluid port and the 6th hydraulic fluid port of described valve body respectively, and the 3rd hydraulic fluid port of described second selector valve and the 4th hydraulic fluid port are communicated with the spring chamber and the non-spring chamber of described two-position four-way pilot operated directional control valve respectively; Described second selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port.

Preferably, described second selector valve is the two-position four-way solenoid directional control valve.

The telescopic boom control system that the utility model provides comprises one-level telescopic cylinder, secondary telescopic cylinder, first equilibrium valve, second equilibrium valve, handles selector valve and foregoing hydraulic control valve; Wherein, have three core pipes on the piston rod of described one-level telescopic cylinder: the first core pipe is communicated with the rodless cavity of one-level telescopic cylinder, and the second core pipe is used for being communicated with the rodless cavity of secondary telescopic cylinder, and the 3rd core pipe is communicated with the rod chamber of one-level telescopic cylinder; Have two core pipes on the piston rod of described secondary telescopic cylinder: the four-core pipe is communicated with the rod chamber of secondary telescopic cylinder, and the 5th core pipe is communicated with the rodless cavity of secondary telescopic cylinder; And the rod chamber of described secondary telescopic cylinder is communicated with the rod chamber of described one-level telescopic cylinder; Described first equilibrium valve is arranged on the oil circuit that is communicated with one-level telescopic cylinder rodless cavity, and the oil circuit that its control port is communicated with described one-level telescopic cylinder rod chamber is communicated with; Described second equilibrium valve is arranged on the oil circuit that is communicated with secondary telescopic cylinder rodless cavity, and the oil circuit that its control port is communicated with described secondary telescopic cylinder rod chamber is communicated with; Described manipulation selector valve has first hydraulic fluid port, second hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port, and wherein, the 3rd hydraulic fluid port is communicated with the pressure oil circuit, and the 4th hydraulic fluid port is communicated with oil return circuit, and second hydraulic fluid port is communicated with the rod chamber of described one-level telescopic cylinder; Described manipulation selector valve has two working staties: in first working state, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port; In second working state, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; First hydraulic fluid port of described hydraulic control valve is communicated with first hydraulic fluid port of described manipulation selector valve, second hydraulic fluid port of described hydraulic control valve is communicated with oil return circuit, the 3rd hydraulic fluid port of described hydraulic control valve is communicated with the rodless cavity of described one-level telescopic cylinder by first equilibrium valve, and the 4th hydraulic fluid port of described hydraulic control valve is communicated with the second core pipe of described one-level telescopic cylinder.

Preferably, the adjusting force value p ' of the relief valve of described hydraulic control valve meets the following conditions:

$\frac{p{A}_4-f}{A_3}<p^{,}<\min (\frac{p{A}_4+f}{A_3},\frac{F_{\mathrm{cr}}}{A});$

Wherein, $F_{\mathrm{cr}}=\frac{{\mathrm{\&pi;}}^2\mathrm{EI}}{{\left(\mathrm{\&mu;l}\right)}^2};$

Wherein, $I=\frac{\mathrm{\&pi;}}{64}(D^4-d^4),$

In the formula: p-system pressure, A ₄-secondary telescopic cylinder rod chamber area, the starting friction power of f-secondary telescopic cylinder, A ₃-secondary telescopic cylinder rodless cavity area, the circular crosssection area of the A-second core pipe; The effective volume Young's modulus of E-hydraulic medium, the kinetic viscosity of μ-hydraulic medium, the length of the l-second core pipe, the outside diameter of the D-second core pipe ring tee section, the interior circular diameter of the d-second core pipe ring tee section.

Preferably, also have on the valve body of described hydraulic control valve the 5th hydraulic fluid port that is communicated with oil return circuit and the 6th hydraulic fluid port that is communicated with the pilot pressure oil circuit; And described valve body also is integrated with second selector valve, first hydraulic fluid port of described second selector valve and second hydraulic fluid port are communicated with the 5th hydraulic fluid port and the 6th hydraulic fluid port of described valve body respectively, and the 3rd hydraulic fluid port of described second selector valve and the 4th hydraulic fluid port are communicated with the spring chamber and the non-spring chamber of described two-position four-way pilot operated directional control valve respectively; Described second selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port.

Preferably, described second selector valve is the two-position four-way solenoid directional control valve.

The hydraulic control valve that the utility model provides has two working staties, and in first working state, its first hydraulic fluid port is communicated with oil circuit between the 3rd hydraulic fluid port, and the inlet hydraulic of its 4th hydraulic fluid port is during greater than predefined value, the oil circuit conducting of the 4th hydraulic fluid port to the second hydraulic fluid port; In second working state, its first hydraulic fluid port is communicated with oil circuit between the 4th hydraulic fluid port.Be applied in the concrete hydraulic control circuit, the hydraulic control valve that the utility model provides is under first working state, the inlet hydraulic of its 4th hydraulic fluid port has only and satisfies above-mentioned condition and could set up connected relation with second hydraulic fluid port, thereby adapts to the use needs of hydraulic control circuit.Control principle of the present utility model looks for another way, and controls the conducting of oil circuit between the 4th hydraulic fluid port second hydraulic fluid port by set pressure, has stable, the reliable characteristics of Control Parameter.

In the preferred version of hydraulic control valve described in the utility model, described valve body is integrated with two-position four-way pilot operated directional control valve and relief valve; Conversion operations by two-position four-way pilot operated directional control valve working position, the control hydraulic control valve is changed between first working state and second working state, and the control mouth pressure by regulating relief valve is to satisfy connection condition between valve body the 4th hydraulic fluid port to the second hydraulic fluid port.Concrete control procedure: when this two-position four-way pilot operated directional control valve is in first working position, valve body the 4th hydraulic fluid port is communicated with the filler opening of relief valve through the 4th hydraulic fluid port and second hydraulic fluid port of this two-position four-way pilot operated directional control valve, when the inlet hydraulic of valve body the 4th hydraulic fluid port during greater than the control mouth set pressure of relief valve, then relief valve is opened, and this moment, the oil circuit of valve body the 4th hydraulic fluid port to the second hydraulic fluid port was on state.In running, the control mouth pressure of relief valve is comparatively stable after setting up, and meets the requirement of HYDRAULIC CONTROL SYSTEM precision, can further improve the operational reliability of control system

The hydraulic control valve that the utility model provides is specially adapted to the telescopic boom control system.

In the telescopic boom control system that the utility model provides with aforementioned hydraulic control valve, first hydraulic fluid port of described hydraulic control valve is communicated with first hydraulic fluid port of described manipulation selector valve, second hydraulic fluid port of described hydraulic control valve is communicated with oil return circuit, the 3rd hydraulic fluid port of described hydraulic control valve is communicated with the rodless cavity of described one-level telescopic cylinder by first equilibrium valve, and the 4th hydraulic fluid port of described hydraulic control valve is communicated with the second core pipe of described one-level telescopic cylinder.When the secondary telescopic cylinder unrecovered and when regaining the one-level telescopic cylinder, the pressure medium of core tube chamber increases gradually along with the withdrawal of one-level telescopic cylinder, when the pressure medium of core tube chamber during greater than the set pressure of described relief valve, relief valve is opened increase, fluid in this chamber flows back to fuel tank, thereby avoids pressure medium in the core tube chamber too high and cause the phenomenon of core canal curvature.In addition, in use, the set pressure of relief valve can not be subjected to Effect of Environmental and change, and therefore, adopts relief valve to control one-level telescopic cylinder core tube chamber inner fluid pressure and has higher working stability.In addition, hydraulic control valve is in second working state, the non-connection of oil circuit between its second hydraulic fluid port and the 3rd hydraulic fluid port; So design when carrying out secondary telescopic cylinder recovery operation, can effectively be avoided two oil cylinder interlocks.

In the preferred version of telescopic boom control system described in the utility model, the control mouth of relief valve is regulated force value p ' and should be satisfied: $\frac{p{A}_4-\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}}<p^{,}<\min (\frac{\mathrm{<figure-callout\; id="4"\; label="p\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">p</figure-callout>}{A}_{}{}_4+\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}},\frac{F_{\mathrm{cr}}}{A}).$ Wherein, the setting value of relief valve greater than

The interlock of secondary telescopic cylinder is regained when avoiding the one-level telescopic cylinder to regain; The setting value of relief valve less than

The interlock of secondary telescopic cylinder is stretched out when avoiding the one-level telescopic cylinder to regain, and the setting value of relief valve less than

The too high phenomenon that causes the core canal curvature of pressure medium of core tube chamber when avoiding the one-level telescopic cylinder to regain.This preferred version can further improve the functional reliability of telescopic boom control system.

Description of drawings

Fig. 1 is the working principle that existing twin-tub adds rope row formula extending means control system;

Fig. 2 is the overall structure sectional view of existing one-level telescopic cylinder;

Fig. 3 is the hydraulic schematic diagram of telescopic boom control system described in the utility model;

Fig. 4 is the fundamental diagram of hydraulic control valve described in the utility model.

Among Fig. 3 and Fig. 4:

One-level telescopic cylinder 1, the first core pipe 11, the second core pipe 12, the 3rd core pipe 13;

Secondary telescopic cylinder 2, four-core pipe 21, the 5th core pipe 22;

First equilibrium valve 3;

Second equilibrium valve 4;

Hydraulic control valve 5, the first hydraulic fluid port A, the second hydraulic fluid port B, the 3rd hydraulic fluid port C, the 4th hydraulic fluid port D, the 5th hydraulic fluid port X, the 6th hydraulic fluid port Y;

Handle selector valve 6, the first hydraulic fluid port 6a, the second hydraulic fluid port 6b, the 3rd hydraulic fluid port 6c, the 4th hydraulic fluid port 6d;

Two-position four-way pilot operated directional control valve 7, the first hydraulic fluid port 7a, the second hydraulic fluid port 7b, the 3rd hydraulic fluid port 7c, the 4th hydraulic fluid port 7d;

Relief valve 8, filler opening 8a, oil outlet 8b;

Two-position four-way solenoid directional control valve 9, the first hydraulic fluid port 9a, the second hydraulic fluid port 9b, the 3rd hydraulic fluid port 9c, the 4th hydraulic fluid port 9d.

Embodiment

The utility model provides a kind of hydraulic control valve 5, the valve body of this control valve has the first hydraulic fluid port A, the second hydraulic fluid port B, the 3rd hydraulic fluid port C and the 4th hydraulic fluid port D, this manipulation selector valve has two working staties: in first working state, its first hydraulic fluid port A is communicated with oil circuit between the 3rd hydraulic fluid port C, the inlet hydraulic of its second hydraulic fluid port B is during greater than predefined value, the oil circuit conducting of the second hydraulic fluid port B to the, four hydraulic fluid port D; In second working state, its first hydraulic fluid port A is communicated with oil circuit between the 4th hydraulic fluid port D.The work control principle of hydraulic control valve described in the utility model looks for another way, and controls the conducting of oil circuit between the 4th hydraulic fluid port second hydraulic fluid port by set pressure, has stable, the reliable characteristics of Control Parameter.

Specify present embodiment below in conjunction with Figure of description.

Be without loss of generality, present embodiment is that example is elaborated with the telescopic boom control system with telescopic cylinder of two stages.

The innermost layer arm joint that described herein minor details arm is a telescopic hoist boom, when arm stretched out fully, the minor details arm was positioned at foremost; Described basic arm joint is the outermost surface arm joint of telescopic hoist boom, and it is connected with turntable.

Referring to Fig. 3, this figure is the hydraulic schematic diagram of telescopic boom control system described in the utility model.

As shown in Figure 3, the telescopic boom control system that provides of the utility model adopts stretching out of the telescopic cylinder of two stages or regains with the operation of realization to telescopic boom.

One-level telescopic cylinder 1 is used to drive and saves stretching out of close arm joint with basic arm or regains, is example with four joint arms, is used to drive two and saves stretching out or regaining of arms.Have three core pipes on the piston rod of one-level telescopic cylinder 1, wherein, the first core pipe 11 is communicated with the rodless cavity of one-level telescopic cylinder 1, and the 3rd core pipe 13 is communicated with the rod chamber of one-level telescopic cylinder 1, and the second core pipe 12 is used for being communicated with the rodless cavity of secondary telescopic cylinder 2.

Secondary telescopic cylinder 2 is used to drive stretching out of close arm joint with the minor details arm or regains, is example with four joint arms, is used to drive three joint arms and four and saves stretching out of arms or regain.Have two core pipes on the piston rod of secondary telescopic cylinder 2, wherein, four-core pipe 21 is communicated with the rod chamber of secondary telescopic cylinder 2, and the 5th core pipe 22 is communicated with the rodless cavity of secondary telescopic cylinder 2.

Need to prove, the composition of telescopic cylinder of one-level described in the present embodiment 1 and secondary telescopic cylinder 2 and annexation and prior art are identical, both compounding practices are to realize stretching out or regaining of telescopic boom, those of ordinary skill in the art can realize fully based on prior art, not repeat them here.

As shown in Figure 3, first equilibrium valve 3 is arranged on the oil circuit that is communicated with the rodless cavity of one-level telescopic cylinder 1, that is, be communicated with the rodless cavity of one-level telescopic cylinder 1 by the connecting pipeline and the first core pipe 11; The control port of first equilibrium valve 3 is communicated with the hydraulic fluid port of one-level telescopic cylinder 1 rod chamber; Second equilibrium valve 4 is arranged on the oil circuit that is communicated with the rodless cavity of secondary telescopic cylinder 2, that is, be communicated with the rodless cavity of secondary telescopic cylinder 2 by connecting pipeline and the 5th core pipe 22, and the control port of second equilibrium valve 4 is communicated with the hydraulic fluid port of secondary telescopic cylinder 2 rod chambers.

Handle selector valve 6 and be used to control stretching out or recovery operation of telescopic cylinder.This manipulation selector valve 6 has the first hydraulic fluid port 6a, the second hydraulic fluid port 6b, the 3rd hydraulic fluid port 6c and the 4th hydraulic fluid port 6d, wherein, the 3rd hydraulic fluid port 6c is communicated with the system pressure oil circuit, the 4th hydraulic fluid port 6d is communicated with the system oil return oil circuit, the first hydraulic fluid port 6a is communicated with the first hydraulic fluid port A of hydraulic control valve 5, and the second hydraulic fluid port 6b is communicated with the rod chamber of one-level telescopic cylinder 1 by connecting pipeline and the 3rd core pipe 13; In addition, this manipulation selector valve 6 has two working staties: in first working state (position, a left side), its first hydraulic fluid port 6a is communicated with the 3rd hydraulic fluid port 6c, the second hydraulic fluid port 6b is communicated with the 4th hydraulic fluid port 6d, and telescopic cylinder stretches out under this state; In second working state (right position), its first hydraulic fluid port 6a is communicated with the 4th hydraulic fluid port 6d, the second hydraulic fluid port 6b is communicated with the 3rd hydraulic fluid port 6c, and telescopic cylinder is regained under this state.Shown in the figure, handle selector valve 6 and be specially manual three position four-way directional control valve.

The second hydraulic fluid port B of hydraulic control valve 5 is communicated with oil return circuit, the 3rd hydraulic fluid port C of hydraulic control valve 5 is communicated with the rodless cavity of one-level telescopic cylinder 1 by first equilibrium valve 3 and the first core pipe 11, and the 4th hydraulic fluid port D of hydraulic control valve 5 is communicated with the second core pipe 12 of one-level telescopic cylinder 1.

See also Fig. 4, this figure is the fundamental diagram of the described hydraulic control valve of present embodiment.

Particularly, the valve body of hydraulic control valve 5 is integrated with first selector valve and relief valve 8.

As shown in Figure 4, first selector valve adopts two-position four-way pilot operated directional control valve 7, this valve has four hydraulic fluid ports: its first hydraulic fluid port 7a, the 3rd hydraulic fluid port 7c and the 4th hydraulic fluid port 7d are communicated with the first hydraulic fluid port A, the 3rd hydraulic fluid port C and the 4th hydraulic fluid port D of valve body respectively, and its second hydraulic fluid port 7b is communicated with the filler opening 8a of relief valve 8; The oil outlet 8b of relief valve 8 is communicated with the second hydraulic fluid port B of valve body.

Wherein, first selector valve has two working positions: in first working position (position, a left side), its first hydraulic fluid port 7a is communicated with the 3rd hydraulic fluid port 7c, the second hydraulic fluid port 7b is communicated with the 4th hydraulic fluid port 7d; In second working position (right position), its first hydraulic fluid port 7a is communicated with the 4th hydraulic fluid port 7d, the second hydraulic fluid port 7b is with the 3rd hydraulic fluid port 7c is non-is communicated with; And when the inlet hydraulic of the 4th hydraulic fluid port D of this valve during greater than the adjusting pressure set points of relief valve 8, the 4th hydraulic fluid port 7d of first selector valve and the second hydraulic fluid port B of valve body are communicated with.When control fluid acted on the spring chamber of described two-position four-way pilot operated directional control valve 7, this valve was in first working position; When control fluid acted on the non-spring chamber of described hydraulic control two-position four way change valve 7, this valve was in second working position.

In addition, the applying working condition of do not regain at secondary telescopic cylinder 2, one-level telescopic cylinder 1 being regained, the setting of the adjusting force value p ' of relief valve 8 need be satisfied three conditions: the second core pipe does not produce bending deflection; Secondary telescopic cylinder 2 withdrawal that do not link; Secondary telescopic cylinder 2 does not link and stretches out.

One, p ' satisfy the second core pipe and do not produce diastrophic being analyzed as follows:

Critical pressure is during core pipe neutrality: $F_{\mathrm{cr}}=\frac{{\mathrm{\&pi;}}^2\mathrm{EI}}{{\left(\mathrm{\&mu;l}\right)}^2},$ Wherein, $I=\frac{\mathrm{\&pi;}}{64}(D^4-d^4);$ In the formula, the effective volume Young's modulus of E-hydraulic medium, the kinetic viscosity of μ-hydraulic medium, the length of the l-second core pipe, the outside diameter of the D-second core pipe ring tee section, the interior circular diameter of the d-second core pipe ring tee section.So, the setting pressure of relief valve $p^{,}<\frac{F_{\mathrm{cr}}}{A}$ The time can guarantee that the core pipe is not crooked.

Its two, what p ' meeting tier 2 telescopic cylinder 2 did not link and regains being analyzed as follows:

P ' under this state=p ₃, p=p ₄, work as p ' * A ₃+ f＜p * A ₄, in the formula: p-system pressure, A ₄-secondary telescopic cylinder rod chamber area, the starting friction power of f-secondary telescopic cylinder, A ₃-secondary telescopic cylinder rodless cavity area.That is, $p^{,}<\frac{p\&times;A_4-\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}}$ The time secondary telescopic cylinder 2 withdrawal that do not link.

Its three, what p ' meeting tier 2 telescopic cylinder 2 did not link and stretches out is analyzed as follows:

If the starting friction power of oil cylinder is f, when one-level telescopic cylinder 1 is regained, cause the second core pipe inner volume to reduce, produce the pressure of Δ p and link to each other, as Δ p * A with the rodless cavity chamber of secondary flexible 2 ₃＞p * A ₄+ f, that is, $\mathrm{\&Delta;p}>\frac{p\&times;A_4+\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}}$ The time secondary telescopic cylinder 2 do not link and stretch out.

Comprehensive above-mentioned three kinds of status analysis, the adjusting force value p ' of described relief valve should meet the following conditions:

$\frac{p{A}_4-\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}}<p^{,}<\min (\frac{\mathrm{<figure-callout\; id="4"\; label="p\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">p</figure-callout>}{A}_{}{}_4+\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}},\frac{F_{\mathrm{cr}}}{A}).$

Further, hydraulic control valve 5 also is integrated with second selector valve, adopts second selector valve to coordinate pilot pressure oil circuit L and is communicated with the spring chamber or the non-spring chamber of aforementioned pilot operated directional control valve 7.As shown in Figure 4, particularly, second selector valve adopts two-position four-way solenoid directional control valve 9.In addition, also have on the valve body of hydraulic control valve 5 the 5th hydraulic fluid port X that is communicated with oil return circuit and the 6th hydraulic fluid port Y that is communicated with pilot pressure oil circuit L.The first hydraulic fluid port 9a of second selector valve and the second hydraulic fluid port 9b are communicated with the 5th hydraulic fluid port X and the 6th hydraulic fluid port Y of valve body respectively, and the 3rd hydraulic fluid port 9c of second selector valve and the 4th hydraulic fluid port 9d are communicated with the spring chamber and the non-spring chamber of two-position four-way pilot operated directional control valve 7 respectively; This second selector valve has two working positions: in first working position (position, a left side), its first hydraulic fluid port 9a is communicated with the 4th hydraulic fluid port 9d, the second hydraulic fluid port 9b is communicated with the 3rd hydraulic fluid port 9c, pilot pressure fluid acts on the spring chamber of two-position four-way pilot operated directional control valve 7, under this state, two-position four-way pilot operated directional control valve 7 is in position, a left side; In second working position (right position), its first hydraulic fluid port 9a is communicated with the 3rd hydraulic fluid port 9c, the second hydraulic fluid port 9b is communicated with the 4th hydraulic fluid port 9d, pilot pressure fluid acts on the non-spring chamber of two-position four-way pilot operated directional control valve 7, and under this state, two-position four-way pilot operated directional control valve 7 is in right position.

The working procedure of telescopic boom control system described in the utility model is summarized as follows.

One, one-level telescopic cylinder 1 stretches out operating mode, handles selector valve 6 and is in position, a left side, is in position, a left side after solenoid directional control valve 9 dead electricity, and the constant pressure oil of the 5th hydraulic fluid port 9a flows to the spring chamber of pilot operated directional control valve 7, makes pilot operated directional control valve 7 be in position, a left side.

Oil-feed: the rodless cavity of the first core pipe 11-one-level telescopic cylinder 1 of the one-way valve-one-level telescopic cylinder 1 of the 3rd hydraulic fluid port C-first equilibrium valve 3 of the first hydraulic fluid port A-hydraulic control valve 5 of system pressure oil circuit P-hydraulic control valve 5; Oil return: the 3rd core pipe 13-system oil return oil circuit T of the rod chamber of one-level telescopic cylinder 1-one-level telescopic cylinder 1.

In this control procedure, the pressure P 1 of one-level telescopic cylinder 1 rodless cavity equals input pressure P, and the return pressure P2 of one-level telescopic cylinder 1 is a return pressure, and is not enough so that first equilibrium valve 3 is in position, a left side.Because P1 * A1 is greater than P2 * A2, so one-level telescopic cylinder 1 stretches out.In addition, the rod chamber of the rod chamber of one-level telescopic cylinder 1 and secondary telescopic cylinder 2 communicates, and underpressure is so that secondary telescopic cylinder 2 withdrawal, and second equilibrium valve 4 is in right position, the fluid of secondary telescopic cylinder 2 rodless cavities is ended by the one-way valve of second equilibrium valve 4, and secondary telescopic cylinder 2 can't be realized retraction at this moment.

Two, secondary telescopic cylinder 2 stretches out operating mode, handles selector valve 6 and is in position, a left side, is in right position after solenoid directional control valve 9 energisings, and the constant pressure oil of the 5th hydraulic fluid port 9a flows to the non-spring chamber of pilot operated directional control valve 7, makes pilot operated directional control valve 7 be in right position.

Oil-feed: the rodless cavity of the 5th core pipe 22-secondary telescopic cylinder 2 of the one-way valve-secondary telescopic cylinder 2 of the second core pipe 12-, second equilibrium valve 4 of the 4th hydraulic fluid port D-one-level telescopic cylinder 1 of the first hydraulic fluid port A-hydraulic control valve 5 of system pressure oil circuit P-hydraulic control valve 5; Oil return: the 3rd core pipe 13-system oil return oil circuit T of the rod chamber-one-level telescopic cylinder 1 of the four-core pipe 21-one-level telescopic cylinder 1 of the rod chamber of secondary telescopic cylinder 2-secondary telescopic cylinder 2.

In this control procedure, the pressure P 3 of secondary telescopic cylinder 2 rodless cavities equals input pressure P, and the return pressure P4 of secondary telescopic cylinder 2 is a return pressure, and is not enough so that second equilibrium valve 4 is in position, a left side.Because P3 * A3 is greater than P4 * A4, so secondary telescopic cylinder 2 stretches out.In addition, the rod chamber of the rod chamber of secondary telescopic cylinder 2 and one-level telescopic cylinder 1 communicates, and underpressure is so that one-level telescopic cylinder 1 withdrawal, and first equilibrium valve 3 is in right position, the fluid of one-level telescopic cylinder 1 rodless cavity is ended by the one-way valve of first equilibrium valve 3, and one-level telescopic cylinder 1 can't be realized retraction at this moment.

Three, secondary telescopic cylinder 2 is regained operating mode, handles selector valve 6 and is in right position, is in right position after solenoid directional control valve 9 energisings, and the constant pressure oil of the 5th hydraulic fluid port 9a flows to the non-spring chamber of pilot operated directional control valve 7, makes pilot operated directional control valve 7 be in right position.

Oil-feed: the rod chamber of the four-core pipe 21-secondary telescopic cylinder 2 of the rod chamber-secondary telescopic cylinder 2 of the 3rd core pipe 13-one-level telescopic cylinder 1 of system pressure oil circuit P-one-level telescopic cylinder 1; Oil return: the first hydraulic fluid port A-system oil return oil circuit T of the 4th hydraulic fluid port D-hydraulic control valve 5 of the second core pipe 12-hydraulic control valve 5 of the 5th core pipe 22-second equilibrium valve 4-one-level telescopic cylinder 1 of the rodless cavity of secondary telescopic cylinder 2-secondary telescopic cylinder 2.

In this control procedure, input pressure makes win equilibrium valve 3 and second equilibrium valve 4 be in position, a left side, and the return pressure P3 of secondary telescopic cylinder 2 is a return pressure, because P3 * A3 is less than P4 * A4, so 2 withdrawals of secondary telescopic cylinder.In addition, the fluid that rodless cavity is arranged of one-level telescopic cylinder 1 is by the three hydraulic fluid port C of first equilibrium valve 3 to hydraulic control valve 5, and this moment, pilot operated directional control valve 7 was in right position, and the 3rd hydraulic fluid port shutoff is so one-level telescopic cylinder 1 can't be regained; The particular function structure of the right position design of pilot operated directional control valve 7 can effectively be avoided two oil cylinder interlocks.

Four, one-level telescopic cylinder 1 is regained operating mode, handles selector valve 6 and is in right position, is in position, a left side after solenoid directional control valve 9 dead electricity, and the constant pressure oil of the 5th hydraulic fluid port 9a flows to the spring chamber of pilot operated directional control valve 7, makes pilot operated directional control valve 7 be in position, a left side.

Oil-feed: the rod chamber of the 3rd core pipe 13-one-level telescopic cylinder 1 of system pressure oil circuit P-one-level telescopic cylinder 1; Oil return: the first hydraulic fluid port A-system oil return oil circuit T of the 3rd hydraulic fluid port C-hydraulic control valve 5 of the first core pipe 11-, the first equilibrium valve 3-hydraulic control valve 5 of the rodless cavity of one-level telescopic cylinder 1-one-level telescopic cylinder 1.

In this control procedure, input pressure makes win equilibrium valve 3 and second equilibrium valve 4 be in position, a left side, and the return pressure P1 of one-level telescopic cylinder 1 is a return pressure, because P1 * A1 is less than P2 * A2, so 1 withdrawal of one-level telescopic cylinder.In addition, carry out the recovery operation of one-level telescopic oil cylinder 1 when secondary telescopic oil cylinder 2 is not regained, the rod chamber of the rod chamber of one-level telescopic cylinder 1 and secondary telescopic cylinder 2 communicates, because the setting of relief valve 8 $\frac{p{A}_4-\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}}<p^{,}<\min (\frac{\mathrm{<figure-callout\; id="4"\; label="p\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">p</figure-callout>}{A}_{}{}_4+\mathrm{<figure-callout\; id="3"\; label="f\; A"\; filenames="Y2009200063970020H1.png"\; state="\{\{state\}\}">f</figure-callout>}}{A_{}},\frac{F_{\mathrm{cr}}}{A}),$ So can guarantee that the not crooked and secondary telescopic cylinder 2 of core pipe can not link this moment stretches out or regains.

The above only is a preferred implementation of the present utility model; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection domain of the present utility model.

Claims (10)

1, hydraulic control valve is characterized in that, the valve body of this control valve has first hydraulic fluid port, second hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port, and this control valve has two working staties:

In first working state, its first hydraulic fluid port is communicated with oil circuit between the 3rd hydraulic fluid port, and the inlet hydraulic of its second hydraulic fluid port is during greater than predefined value, the oil circuit conducting of second hydraulic fluid port to the, four hydraulic fluid ports;

In second working state, its first hydraulic fluid port is communicated with oil circuit between the 4th hydraulic fluid port.

2, hydraulic control valve according to claim 1 is characterized in that, in second working state, and non-connection of oil circuit between its second hydraulic fluid port and the 3rd hydraulic fluid port.

3, hydraulic control valve according to claim 2 is characterized in that, described valve body is integrated with first selector valve and relief valve; Described first selector valve has four hydraulic fluid ports: its first hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port are communicated with first hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port of valve body respectively, and its second hydraulic fluid port is communicated with the filler opening of described relief valve; The oil outlet of described relief valve is communicated with second hydraulic fluid port of described valve body;

Described first selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port is non-;

The inlet hydraulic of the 4th hydraulic fluid port of described valve body is during greater than the adjusting pressure set points of described relief valve, and the 4th hydraulic fluid port of described first selector valve and second hydraulic fluid port of valve body are communicated with.

4, hydraulic control valve according to claim 3 is characterized in that, described first selector valve is the two-position four-way pilot operated directional control valve; When control fluid acted on the spring chamber of described two-position four-way pilot operated directional control valve, this valve was in first working position; When control fluid acted on the non-spring chamber of described hydraulic control two-position four way change valve, this valve was in second working position.

5, hydraulic control valve according to claim 4 is characterized in that, also has on the described valve body:

The 5th hydraulic fluid port is used for being communicated with oil return circuit; With

The 6th hydraulic fluid port is used for being communicated with the pilot pressure oil circuit; And

Described valve body also is integrated with second selector valve, first hydraulic fluid port of described second selector valve and second hydraulic fluid port are communicated with the 5th hydraulic fluid port and the 6th hydraulic fluid port of described valve body respectively, and the 3rd hydraulic fluid port of described second selector valve and the 4th hydraulic fluid port are communicated with the spring chamber and the non-spring chamber of described two-position four-way pilot operated directional control valve 7 respectively;

Described second selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port.

6, hydraulic control valve according to claim 5 is characterized in that, described second selector valve is the two-position four-way solenoid directional control valve.

7, telescopic boom control system comprises:

The one-level telescopic cylinder has three core pipes on its piston rod: the first core pipe is communicated with the rodless cavity of one-level telescopic cylinder, and the second core pipe is used for being communicated with the rodless cavity of secondary telescopic cylinder, and the 3rd core pipe is communicated with the rod chamber of one-level telescopic cylinder;

The secondary telescopic cylinder, have two core pipes on its piston rod: the four-core pipe is communicated with the rod chamber of secondary telescopic cylinder, and the 5th core pipe is communicated with the rodless cavity of secondary telescopic cylinder; And the rod chamber of described secondary telescopic cylinder is communicated with the rod chamber of described one-level telescopic cylinder;

First equilibrium valve is arranged on the oil circuit that is communicated with one-level telescopic cylinder rodless cavity, and the oil circuit that its control port is communicated with described one-level telescopic cylinder rod chamber is communicated with;

Second equilibrium valve is arranged on the oil circuit that is communicated with secondary telescopic cylinder rodless cavity, and the oil circuit that its control port is communicated with described secondary telescopic cylinder rod chamber is communicated with; With

Handle selector valve, it has first hydraulic fluid port, second hydraulic fluid port, the 3rd hydraulic fluid port and the 4th hydraulic fluid port, and wherein, the 3rd hydraulic fluid port is communicated with the pressure oil circuit, and the 4th hydraulic fluid port is communicated with oil return circuit, and second hydraulic fluid port is communicated with the rod chamber of described one-level telescopic cylinder; Described manipulation selector valve has two working staties: in first working state, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port; In second working state, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; It is characterized in that, also comprise:

As each described hydraulic control valve in the claim 1 to 4;

First hydraulic fluid port of described hydraulic control valve is communicated with first hydraulic fluid port of described manipulation selector valve, second hydraulic fluid port of described hydraulic control valve is communicated with oil return circuit, the 3rd hydraulic fluid port of described hydraulic control valve is communicated with the rodless cavity of described one-level telescopic cylinder by first equilibrium valve, and the 4th hydraulic fluid port of described hydraulic control valve is communicated with the second core pipe of described one-level telescopic cylinder.

8, telescopic boom control system according to claim 7 is characterized in that, the adjusting force value p ' of the relief valve of described hydraulic control valve meets the following conditions:

$\frac{{\mathrm{pA}}_4-f}{A_3}<p^{,}<\min (\frac{{\mathrm{pA}}_4+f}{A_3},\frac{F_{\mathrm{cr}}}{A}),$

Wherein,

Wherein,

In the formula: p-system pressure, A4-secondary telescopic cylinder rod chamber area, the starting friction power of f-secondary telescopic cylinder, A3-secondary telescopic cylinder rodless cavity area, the circular crosssection area of the A-second core pipe; The effective volume Young's modulus of E-hydraulic medium, the kinetic viscosity of μ-hydraulic medium, the length of the l-second core pipe, the outside diameter of the D-second core pipe ring tee section, the interior circular diameter of the d-second core pipe ring tee section.

9, according to claim 7 or 8 described telescopic boom control system, it is characterized in that also having on the valve body of described hydraulic control valve:

The 5th hydraulic fluid port X is communicated with oil return circuit; With

The 6th hydraulic fluid port Y is communicated with the pilot pressure oil circuit; And

Described valve body also is integrated with second selector valve, first hydraulic fluid port of described second selector valve and second hydraulic fluid port are communicated with the 5th hydraulic fluid port and the 6th hydraulic fluid port of described valve body respectively, and the 3rd hydraulic fluid port of described second selector valve and the 4th hydraulic fluid port are communicated with the spring chamber and the non-spring chamber of described two-position four-way pilot operated directional control valve respectively;

Described second selector valve has two working positions: in first working position, its first hydraulic fluid port is communicated with the 4th hydraulic fluid port, second hydraulic fluid port is communicated with the 3rd hydraulic fluid port; In second working position, its first hydraulic fluid port is communicated with the 3rd hydraulic fluid port, second hydraulic fluid port is communicated with the 4th hydraulic fluid port.

10, telescopic boom control system according to claim 9 is characterized in that, described second selector valve is the two-position four-way solenoid directional control valve.

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