CN209212691U - Piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder - Google Patents

Abstract

The utility model discloses a kind of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinders, are related to hydraulic cylinder field, comprising: cylinder body；What at least two-stage was arranged step by step is set to the intracorporal piston rod assembly of cylinder, and every grade of piston rod assembly includes piston and piston rod.Multiple check valve assemblies, each check valve assembly include the cylinder internal check valve for being connected to or stopping for controlling the rod chamber of adjacent two-stage piston rod assembly.Pin-lift arrangement is opened or closed for driving cylinder internal check valve, and when the piston in adjacent two-stage piston rod assembly separates during stretching or retraction, pin-lift arrangement is self-locking.When the piston in adjacent two-stage piston rod assembly contacts during stretching or retraction, pin-lift arrangement driving cylinder internal check valve is opened.Valve group is balanced, is fixed on the piston rod of minimum first stage piston bar assembly.The utility model can solve the problem that conventional multi-level hydraulic cylinder uses radial hole to bring sealing ring easy to wear, avoid leakage in hydraulic cylinder, guaranteeing every one-stage hydraulic cylinder is not in superpressure phenomenon.

Description

Piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder

Technical field

The utility model relates to hydraulic cylinder fields, and in particular to a kind of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder.

Background technique

On hydraulic construction machine or Large Hydraulic Equipment, due to being limited by installation space, load it is complicated and changeable, lead to It often needs using multistage hydraulic cylinder, and works under alternating load.Common multistage hydraulic cylinder, in order to guarantee the flexible of hydraulic cylinder Sequentially, the structure of radial hole is generally had using cylinder barrel, which requiring to be widely used in very high engineering machinery.By It is necessarily less than the width of piston seal in cylinder barrel radial direction bore dia, usually not less than 2mm need to be along diameter to guarantee circulation area It is more to uniformly distributed quantity, and inner wall of cylinder diameter again it is small, inconvenience operation, thus be difficult all handle it is round and smooth, thus unavoidably Bring sealing ring cross radial hole bring be prone to wear out even shear the problem of.The problem short time use, not will cause compared with Big harm, but long-term uses, and will necessarily bring in the hydraulic cylinder caused due to sealing ring damage and leak through big cisco unity malfunction.

Have a kind of Double Acting Telescopic Hydraulic Cylinder under loading condition in the prior art, hydraulic cylinder into and out of hydraulic fluid port Balanced valve is installed, to be suitable for load；Simultaneously to guarantee the stretching of multistage hydraulic cylinder, contracting order (mainly retraction), one Grade piston and second piston end are provided with the stroke valve of lance, since the lance of stroke valve is exposed to the interior oil of hydraulic cylinder In liquid, thus stroke valve must be taken into consideration the problem of differential pressure action is opened, to prevent stroke valve from surprisingly opening, cracking pressure It is typically set at oil cylinder rated operating pressure, it is contemplated that the set pressure and Double Acting Telescopic Hydraulic Cylinder of balanced valve are biggish Piston area ratio (rodless cavity/rod chamber), in the case where the debugging initial stage of oil cylinder is vented insufficient or unexpected random cylinder, when Hydraulic cylinder can generate hydraulic cylinder rod chamber superpressure when stretching out, and cause hydraulic cylinder to damage when serious.

Utility model content

In view of the deficiencies in the prior art, the purpose of this utility model is to provide a kind of piston rod oil inlet double actings Multistage hydraulic cylinder can effectively solve Double Acting Telescopic Hydraulic Cylinder under alternating load the problem of cisco unity malfunction, and tradition The problem of multistage hydraulic cylinder is prone to wear out using radial hole bring sealing ring avoids leakage in hydraulic cylinder, and uses commonly The problem of hydraulic cylinder brought by the pressure regulator valves such as stroke valve is easy to superpressure, guaranteeing every one-stage hydraulic cylinder is not in that superpressure is existing As.

To achieve the above objectives, the technical scheme adopted by the utility model is that:

A kind of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder, comprising:

Cylinder body；

At least piston rod assembly that is arranged step by step of two-stage is set in the cylinder body, and every grade of piston rod assembly includes living The piston rod filled in and be fixed on piston, and every grade of piston rod assembly has bar for what the accommodating space where it was divided into corresponding level Chamber and rodless cavity；

Multiple check valve assemblies, each check valve assembly are set to the higher piston of adjacent two-stage piston rod assembly In the piston of bar assembly, each check valve assembly includes,

Cylinder internal check valve is used to control the rod chamber connection of adjacent two-stage piston rod assembly or stops；

Pin-lift arrangement is used to that the cylinder internal check valve to be driven to open or close, and the pin-lift arrangement is configured to: When the piston in adjacent two-stage piston rod assembly separates during stretching or retraction, the pin-lift arrangement is self-locking, described Cylinder internal check valve is closed, and the rod chamber of adjacent two-stage piston rod assembly is stopped；When the piston in adjacent two-stage piston rod assembly exists When stretching out or contacting during retracting, the pin-lift arrangement drives the cylinder internal check valve to open, and makes adjacent two-stage piston rod The rod chamber of component is connected to；And

Valve group is balanced, is fixed on the piston rod of minimum first stage piston bar assembly, the balance valve group is for controlling institute State the oil inlet or oil return of rod chamber, and the oil inlet or oil return of the control rodless cavity.

Based on the above technical solution, the pin-lift arrangement is at least partially disposed at outside piston, when adjacent two-stage piston After the piston rod assembly of lower level retracts in place in bar assembly, the pin-lift arrangement is located at the part outside piston by external force When, the pin-lift arrangement drives the cylinder internal check valve to open, and is connected to the rod chamber of adjacent two-stage piston rod assembly.

It based on the above technical solution, include each two in the piston equipped with the check valve assembly along correspondence The first oil duct and the second oil duct of piston radial setting, first oil duct and the second oil duct respectively with adjacent two-stage piston rod group One rod chamber of part is connected to, and the cylinder internal check valve is equipped with inlet and outlet, and the import is connected to second oil duct, The outlet is connected to first oil duct.

Based on the above technical solution, the pin-lift arrangement includes:

Top stem casing, interior to be equipped with the first receiving portion, first receiving portion is connected to second oil duct；

First mandril is fixed in the receiving portion, and first mandril can be moved back and forth in the first receiving portion, And the import is passed through to drive the cylinder internal check valve to open, and first mandril is additionally provided with the second receiving portion；

Second mandril is arranged in second receiving portion, and second mandril can be past in second receiving portion Return movement, second mandril is at least partially disposed at outside second receiving portion, and second mandril be axially arranged with along it is logical Hole；

Locking mechanism is used to open and release the lock that first mandril moves back and forth in first receiving portion Fixed, when opening locking, the pin-lift arrangement is self-locking；

First driving device is set in first receiving portion, and the first driving device is for driving described first Mandril is mobile towards the direction locked by the locking mechanism；And

Second driving device is set in second receiving portion, and second driving device is for driving described second Mandril is mobile, and the locking mechanism is made to lock first mandril.

Based on the above technical solution, the locking mechanism includes:

Mounting hole, along being arranged radially for first mandril, the mounting hole is equipped with steel ball；

First groove is located on the inner wall of the top stem casing, and first groove is configured to: when the steel ball is located at When in first groove, the steel ball moves back and forth in first receiving portion for limiting first mandril；

Second groove is located on the outer wall of second mandril, and second groove is configured to: when the steel ball position When in second groove, first mandril can move back and forth in first receiving portion.

Based on the above technical solution, the cylinder internal check valve is configured to: when the rod chamber pressure of corresponding level When greater than cylinder internal check valve cracking pressure, the cylinder internal check valve is voluntarily opened.

Based on the above technical solution, the piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder includes:

First stage piston bar assembly is set in the cylinder body, and the first stage piston bar assembly includes first stage piston and level-one The accommodating space of the cylinder body is divided into level-one rod chamber and level-one without bar by piston rod, the first stage piston and first stage piston bar Chamber, the first stage piston are equipped with the check valve assembly；

Second piston bar assembly is set in the first stage piston bar, and the second piston bar assembly includes second piston And the accommodating space of the first stage piston bar is divided into second level rod chamber by second piston rod, the second piston and second piston rod With second level rodless cavity, the second piston is equipped with the check valve assembly；

Three-level piston rod assembly is set in the second piston rod, and the three-level piston rod assembly includes three-level piston With three-level piston rod, the accommodating space of the second piston rod is divided into three-level rod chamber by the three-level piston and three-level piston rod With three-level rodless cavity, and the balance valve group is fixed on the three-level piston rod.

Based on the above technical solution,

Be equipped with first through hole on the first stage piston, second piston and three-level piston, the level-one rodless cavity, second level without Rod cavity and three-level rodless cavity are interconnected by the first stage piston, second piston and three-level piston first through hole.

Based on the above technical solution,

Oil-deflecting rod is additionally provided in the three-level piston rod, the three-level piston rod and oil-deflecting rod form a ring shaped oil passage, institute It states ring shaped oil passage one end to be connected to the balance valve group, the other end is connected to the three-level rod chamber.

Based on the above technical solution, the balance valve group includes,

Balance valve block which is provided with the first oil inlet end, the second oil inlet end and the first oil outlet, also set in the balance valve block Have with first oil inlet end, unilaterally connected first oil outlet of the first oil outlet and with the second oil inlet end unilaterally connected The second oil outlet, first oil outlet is connected with the first through hole of the three-level piston, second oil outlet with it is described Ring shaped oil passage is connected；

First balanced valve, be set to the balance valve block in, first balanced valve respectively with first oil outlet and First oil outlet is connected, and first balanced valve is configured to: when oil enters the second oil outlet from second oil inlet end, First balanced valve is connected to first oil outlet and the first oil outlet by the first balanced valve；And

Second balanced valve, be set to the balance valve block in, second balanced valve respectively with second oil inlet end and Second oil outlet is connected, and second balanced valve is configured to: when oil enters the first oil outlet from first oil inlet end, Second balanced valve is connected to second oil outlet and the second oil inlet end by the second balanced valve.

Based on the above technical solution, Double Acting Telescopic Hydraulic Cylinder balance valve group further includes,

First check valve, the oil inlet of first check valve are connected to first oil inlet end, first check valve Oil outlet be connected to first oil outlet.

Based on the above technical solution, first balanced valve includes,

- the first balanced valve oil inlet is connected to first oil outlet；

- the first load port is connected to the oil outlet of first oil outlet and the first check valve simultaneously；

- the first control port is connected to by oil duct with second oil inlet end；

Based on the above technical solution,

Second balanced valve includes,

- the second balanced valve oil inlet is connected to second oil inlet end；

- the second load port is connected to second oil outlet；

- the second control port is connected to by oil duct with first oil inlet end.

Compared with the prior art, the advantages of the utility model are:

(1) the piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder of the utility model comprising check valve assembly is provided with unidirectional After valve module, can guarantee the flexible sequence of hydraulic cylinder well by cylinder internal check valve and pin-lift arrangement, at the same with it is existing Technology is compared, and does not need to be arranged radially hole along cylinder barrel, so as to avoid leaking through in the hydraulic cylinder caused due to sealing ring damage The problem of big cisco unity malfunction；

(2) the piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder of the utility model, due to using cylinder internal check valve and mandril Device, and the spring force of every group of cylinder internal check valve and pin-lift arrangement does not exceed 100KN, compared with the stroke valve with lance, subtracts The interaction force of piston space is lacked, to better assure that the stretching in order of the multistage hydraulic cylinder under negative load effect. Simultaneously because the cracking pressure very little of cylinder internal check valve, to guarantee when multistage hydraulic cylinder stretches out, regardless of whether there is random cylinder Phenomenon, every one-stage hydraulic cylinder are not in superpressure phenomenon；

(3) the piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder of the utility model comprising balance valve group, due to balancing valve group Including the first oil outlet, the first balanced valve and the second balanced valve, the hydraulic oil of multistage hydraulic cylinder rod chamber can go out by first Hydraulic fluid port, the first balanced valve enter the first oil outlet of balance valve group, and directly return system fuel tank.It is being provided with individual oil return opening That is after the first oil outlet, return flow can be made to efficiently solve, multistage hydraulic cylinder without the reversal valve of multistage hydraulic cylinder Biggish piston area ratio, when causing the oil inlet of hydraulic cylinder rod chamber, rodless cavity return flow is very large (with rod chamber phase Than) the problem of.

Detailed description of the invention

Fig. 1 is structural representation when piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder is fully retracted into the utility model embodiment Figure；

Fig. 2 is structural representation when piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder is all stretched out in the utility model embodiment Figure；

Fig. 3 is the stretching of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder first stage piston bar or second level in the utility model embodiment Structural schematic diagram when piston rod retracts；

Fig. 4 is the stretching of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder second piston rod or three-level in the utility model embodiment Structural schematic diagram when piston rod retracts；

Fig. 5 is structural schematic diagram when check valve assembly pin-lift arrangement is self-locking in the utility model embodiment；

Fig. 6 is structural schematic diagram when check valve assembly pin-lift arrangement is retracted by external force in the utility model embodiment；

Fig. 7 is structural schematic diagram when pin-lift arrangement is self-locking in the utility model embodiment；

Fig. 8 is structural schematic diagram when pin-lift arrangement is retracted by external force in the utility model embodiment；

Fig. 9 is the structural schematic diagram that valve group is balanced in the utility model embodiment.

In figure: 1- top stem casing, the first receiving portion 11-, the first mandril of 2-, the second receiving portion 21-, 22- ejection part, 23- master Body portion, 24- support end, the second mandril of 3-, 31- through-hole, 4- locking mechanism, 41- mounting hole, 42- steel ball, the first groove of 43-, The second groove of 44-, 5- first driving device, the first spring base of 51-, the first spring of 52-, the second driving device of 6-, the second bullet of 61- Spring abutment, 62- second spring, 7- sealing ring, the first snap ring of 8-, the second snap ring of 9-, the first oil duct of 102-, the second oil duct of 103-, 104- ring shaped oil passage, 200- cylinder internal check valve, the unidirectional valve body of 201-, 202- third accommodating space, 203- import, 204- go out Mouthful, 205- spool, 206- third spring, 300- cylinder body, 401- first stage piston, 402- first stage piston bar, 501- second piston, 502- second piston rod, 601- three-level piston, 602- three-level piston rod, 700- oil-deflecting rod, 1000- balance valve block, 1001- One oil inlet end, the second oil inlet end of 1002-, the first oil outlet of 1003-, the first oil outlet of 1004-, the second oil outlet of 1005-, The first balanced valve of 2000-, 2001- the first balanced valve oil inlet, the first load port of 2002-, the first control port of 2003-, 3000- Second balanced valve, 3001- the second balanced valve oil inlet, the second load port of 3002-, the second control port of 3003-, 4000- first Check valve, 5000- pressure measuring tie-in.

Specific embodiment

The utility model is described in further detail with reference to the accompanying drawings and embodiments.

Shown in Figure 1, the utility model embodiment provides a kind of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder, including cylinder Piston rod assembly, multiple check valve assemblies and the balance valve group that body 300, at least two-stage are arranged step by step.

Wherein, the piston rod assembly that at least two-stage is arranged step by step is set in cylinder body 300, and every grade of piston rod assembly includes living The piston rod filled in and be fixed on piston, and every grade of piston rod assembly has bar for what the accommodating space where it was divided into corresponding level Chamber and rodless cavity.

Multiple check valve assemblies, each check valve assembly are set to the higher piston rod group of adjacent two-stage piston rod assembly In the piston of part, each check valve assembly includes,

Cylinder internal check valve 200 is used to control the rod chamber connection of adjacent two-stage piston rod assembly or stops；

Pin-lift arrangement is used for driving cylinder internal check valve 200 and opens or closes, and pin-lift arrangement is configured to: when adjacent When piston in two-stage piston rod assembly separates during stretching or retraction, pin-lift arrangement is self-locking, and cylinder internal check valve 200 closes It closes, the rod chamber of adjacent two-stage piston rod assembly is stopped；When the piston in adjacent two-stage piston rod assembly stretch out or retract When contacting in the process, pin-lift arrangement driving cylinder internal check valve 200 is opened, and is connected to the rod chamber of adjacent two-stage piston rod assembly.

Valve group is balanced, is fixed on the piston rod of minimum first stage piston bar assembly, balance valve group is for controlling rod chamber Oil inlet or oil return, and control rodless cavity oil inlet or oil return.

It include the piston rod assembly that three-level is arranged step by step, difference as a preferable embodiment, in the present embodiment For first stage piston bar assembly, second piston bar assembly and three-level piston rod assembly, wherein first stage piston bar assembly is superior to two Grade piston rod assembly, second piston rod component-level three-level piston rod assembly, the piston rod assembly of minimum level-one are that three-level is living Stopper rod component.

Specifically, first stage piston bar assembly 400, is set in cylinder body 300, first stage piston bar assembly 400 includes level-one The accommodating space of cylinder body 300 is divided into level-one by piston 401 and first stage piston bar 402, first stage piston 401 and first stage piston bar 402 Rod chamber 503 and level-one rodless cavity 404, first stage piston 401 are equipped with check valve assembly；

Second piston bar assembly 500 is set in first stage piston bar 402, and second piston bar assembly 500 includes second piston 501 and second piston rod 502, the accommodating space of first stage piston bar 402 is divided into two by second piston 501 and second piston rod 502 Grade rod chamber 503 and second level rodless cavity 504, second piston 501 are equipped with check valve assembly；

Three-level piston rod assembly 600 is set in second piston rod 502, and three-level piston rod assembly 600 includes three-level piston 601 and three-level piston rod 602, the accommodating space of second piston rod 502 is divided into three by three-level piston 601 and three-level piston rod 602 Grade rod chamber 603 and three-level rodless cavity 604, and balance valve group and be fixed on three-level piston rod 602.

Further, be equipped with first through hole on first stage piston 401, second piston 501 and three-level piston 601, level-one without Rod cavity 404, second level rodless cavity 504 and three-level rodless cavity 604 pass through first stage piston 401, second piston 501 and three-level piston 601 First through hole is interconnected.

Further, oil-deflecting rod 700, three-level piston rod 602 and the formation of oil-deflecting rod 700 are additionally provided in three-level piston rod 602 One ring shaped oil passage 104,104 one end of ring shaped oil passage are connected to balance valve group, and the other end is connected to three-level rod chamber 603.

It is set to for each check valve assembly in the piston of the higher piston rod assembly of adjacent two-stage piston rod assembly, Under conditions of setting there are three rank piston rod assembly, since adjacent two-stage piston rod assembly also refers to first stage piston bar group Part and second piston bar assembly is adjacent, second piston bar assembly and three-level piston rod assembly are adjacent, therefore check valve assembly can be arranged It in first stage piston bar assembly and second piston bar assembly, or is alternatively not set on the piston rod assembly of lowest level Set check valve assembly.This setup can with and so on, be not limited to three rank piston rod assemblies.

In the present embodiment, in order to realize lower level in adjacent two-stage piston rod assembly piston rod assembly retract in place Afterwards, pin-lift arrangement driving cylinder internal check valve 200 is opened, by the way of are as follows:

Pin-lift arrangement is at least partially disposed at outside piston, when the piston rod assembly contracting of lower level in adjacent two-stage piston rod assembly After returning to position, when pin-lift arrangement is located at the part outside piston by external force, pin-lift arrangement driving cylinder internal check valve 200 is opened It opens, and then is connected to the rod chamber of adjacent two-stage piston rod assembly.

In addition, each including two the first oil ducts along corresponding piston radial setting in the piston equipped with check valve assembly 102 and second oil duct 103, the first oil duct 102 and the second oil duct 103 have bar with one of adjacent two-stage piston rod assembly respectively Chamber connection, as a preferable embodiment, the cylinder internal check valve 200 in the present embodiment includes:

Unidirectional valve body 201, it is interior to be equipped with third accommodating space 202,203 He of import is additionally provided on unidirectional valve body 201 Outlet 204, import 203 is connected to the second oil duct 103, and outlet 204 is connected to the first oil duct 102；

Spool 205 is set in third accommodating space 202, and spool 205 can be moved back and forth in third accommodating space 202.

Further, cylinder internal check valve 200 further includes third spring 206, and third spring 206 is for driving 205 court of spool The direction for closing cylinder internal check valve 200 is mobile.

As a preferable embodiment, as shown in figure 3 and figure 4, the pin-lift arrangement in the present embodiment includes: ginseng

Top stem casing 1, interior to be equipped with the first receiving portion 11, the first receiving portion 11 is connected to the second oil duct 103.

First mandril 2 is fixed in the first receiving portion 11, and the first mandril 2 can move back and forth in the first receiving portion 11 It is dynamic, and import 203 is passed through with the unlatching of driving cylinder internal check valve 200, and the first mandril 2 is additionally provided with the second receiving portion 21.

Second mandril 3 is arranged in the second receiving portion 21, and the second mandril 3 can move back and forth in the second receiving portion 21, Second mandril 3 is at least partially disposed at outside the second receiving portion 21, and the second mandril 3 is axially arranged with through-hole 31 along it.

Locking mechanism 4 is used to open and release the locking that the first mandril 2 moves back and forth in the first receiving portion 11, when When opening locking, pin-lift arrangement is self-locking.

First driving device 5 is set in the first receiving portion 11, and first driving device 5 is for driving the first mandril 2 towards quilt The direction that locking mechanism 4 locks is mobile.

Second driving device 6 is set in the second receiving portion 21, and the second driving device 6 is for driving the second mandril 3 to move It is dynamic, so that locking mechanism 4 is locked the first mandril 2.

Further, in this embodiment locking mechanism 4 includes:

Mounting hole 41, along being arranged radially for the first mandril 2, mounting hole 41 is equipped with steel ball 42；

First groove 43 is located on the inner wall of top stem casing 1, and the first groove 43 is configured to: when steel ball 42 is located at first When in groove 43, steel ball 42 moves back and forth in the first receiving portion 11 for limiting the first mandril 2；

Second groove 44 is located on the outer wall of the second mandril 3, and the second groove 44 is configured to: when steel ball 42 is located at the When in two grooves 44, the first mandril 2 can move back and forth in the first receiving portion 11.

As a preferable embodiment, the first driving device 5 in the present embodiment includes:

First spring base 51 is fixed at the end of the first receiving portion 11；

First spring 52 is set on the first mandril 2, and 52 one end of the first spring supports on the first spring base 51, The other end supports on the first mandril 2, makes the pressure holding of the first mandril 2 on the first receiving portion 11.

Further, the first mandril 2 includes:

Ejection part 22 is sheathed in the first spring 52；

Main part 23 comprising support end 24, support end 24 and pressed on the first receiving portion 11 by the first spring 52.

As a preferable embodiment, the second driving device 6 in the present embodiment includes:

Second spring seat 61 is fixed at the end of the second receiving portion 21；

Second spring 62, one end support on second spring seat 61, and the other end supports on the second mandril 3.

In addition, being equipped with sealing ring 7 between main part 23 and the inner wall of top stem casing 1 to play preferable sealing effect.

In order to limit to the first mandril 2, pin-lift arrangement further includes the first snap ring 8, and the first snap ring 8 is arranged in the first bullet The side of spring abutment 51.

In order to limit to the second mandril 3, pin-lift arrangement further includes the second snap ring 9, and the setting of the second snap ring 9 is on the second top The side of bar 3.

The principle of pin-lift arrangement is introduced below:

First mandril 2 is pressed in top stem casing 1 using the first spring 52, is blocked by the first spring base 51 and the first snap ring 8 Fixed, the first mandril 2 can be axially moveable under the first spring 52 or external force in top stem casing 1, the first mandril 2 and top stem casing 1 is sealed using sealing ring 7, the second mandril 3 that can be moved along axis is coaxially installed in the first mandril 2, and use second Snap ring 9 limits, and the second mandril 3 can be stretched out under 62 spring-force driven dual of second spring or be retracted under external force.

There is steel ball 42 between top stem casing 1, the first mandril 2 and the second mandril 3, steel ball 42 is mounted in the first mandril 2 In mounting hole 41 slightly larger than 42 diameter of steel ball, top stem casing 1 and the second mandril 3 are nearby machined with receiving steel ball at steel ball 42 42 the first groove 43 and the second groove 44, the second mandril 3 are axially provided with through-hole 31 and its spring cavity are communicated with outside.

When steel ball 42 is sunk in the second groove 44 of the second mandril 3, the first mandril 2 can be moved in top stem casing 1 along axis Dynamic, when steel ball 42 is sunk in the first groove 43 of top stem casing 1, the first mandril 2 and top stem casing 1 lock immovable.

Piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder in the utility model, due to using the second top for being provided with axially extending bore Bar 3, so that the second mandril 3 is in extended position always under spring force and will no matter whether there is or not the effect of oil pressure Steel ball 42 is pushed out in the first groove 43 of top stem casing 1, so that the first mandril 2 is extremely immovable in 1 internal lock of top stem casing.Work as external force When the second mandril 3 being pushed to retract, steel ball 42 is sunk in the second groove 44 of the second mandril 3, and the first mandril 2 is released with top stem casing 1 Locking, can retract under external force.When external force releases, the first mandril 2, the second mandril 3 are successively stretched under spring force Out.To efficiently solve under the action of pressure difference, pin-lift arrangement leads to the problem of malfunction, convenient and practical, reliable performance.

In conjunction with the principle of above-mentioned pin-lift arrangement, the principle for check valve assembly is introduced again below:

Pin-lift arrangement and cylinder internal check valve 200 are coaxially mounted in piston rod assembly in the valve opening of piston.Pin-lift arrangement The spool 205 of first mandril, 2 face cylinder internal check valve 200, has reserved certain buffer gap between them, prevent deformation, add Work error or vibration etc. cause spool 205 to malfunction.Pin-lift arrangement by the second oil duct 103 by the rod chamber of the same level piston with The import 203 of cylinder internal check valve 200 is connected to, and the outlet 204 of cylinder internal check valve 200 passes through the first oil duct 102 and next stage piston Rod chamber connection.By taking first stage piston bar assembly and second piston bar assembly as an example, the same level piston here refers to that level-one is living Plug 401, next stage piston refers to second piston 501.The rod chamber of the same level piston refers to level-one rod chamber 403, next stage The rod chamber of piston refers to second level rod chamber 503.

Under normal circumstances, when multistage hydraulic cylinder is protruding, pistons at different levels contact with each other, at this time the of pin-lift arrangement One mandril 2 opens the spool 205 of cylinder internal check valve 200, the rod chamber of the same level piston by the second oil duct 103, pin-lift arrangement, Cylinder internal check valve 200 and the first oil duct 102 are connected to the rod chamber of next stage piston, and multistage hydraulic cylinder will be in the work of hydraulic oil It is stretched out step by step under.

When retraction, since pistons at different levels are separated from each other, pin-lift arrangement will be in the lock state, and cylinder internal check valve 200 is closed, The rod chamber of the same level piston can not be connected to the rod chamber of next stage piston, and hydraulic oil can not push the same level piston to retract, only Instantly first stage piston is retracted into bottom, hits the second mandril 3 of the cylinder internal check valve 200 on the same level piston, and pin-lift arrangement passes through the One mandril 2 opens cylinder internal check valve 200, and the rod chamber of the same level piston could be connected to the rod chamber of next stage piston, hydraulic oil The same level piston could be pushed to retract, therefore, multistage hydraulic cylinder retracts step by step in sequence.If it is living initially to stretch out state the same level It fills in and is not contacted between next stage piston, in the state that is separated from each other, pin-lift arrangement is to be in the lock state at this time, single in cylinder It is closed to the spool 205 of valve 200, the rod chamber of the same level piston is not connected to the rod chamber of next stage piston.When the same level piston When rodless cavity oil inlet, the same level piston rod chamber pressure rise will lead to, pressure oil will pass through the second oil duct 103 and pin-lift arrangement It is applied on the spool 205 of cylinder internal check valve 200, and opens cylinder internal check valve 200, be connected to the same level piston rod chamber and next stage Piston rod chamber prevents the same level piston rod chamber from the case where superpressure occur.

Balance valve group in the present embodiment includes balance valve block 1000, the first balanced valve 2000 and the second balanced valve 3000.

Wherein, balance valve block 1000 which is provided with the first oil inlet end 1001, the second oil inlet end 1002 and the first oil outlet 1003, it is additionally provided with and the first oil inlet end 1001, unilaterally connected first oil outlet of the first oil outlet 1003 in balance valve block 1000 1004 and with unilaterally connected second oil outlet 1005 of the second oil inlet end 1002, the first oil outlet 1004 and three-level piston 601 First through hole be connected, the second oil outlet 1005 is connected with ring shaped oil passage 104.

First balanced valve 2000, be set to balance valve block 1000 in, the first balanced valve 2000 respectively with the first oil outlet 1003 are connected with the first oil outlet 1004, and the first balanced valve 2000 is configured to: when oil enters from the second oil inlet end 1002 When two oil outlets 1005, the first balanced valve 2000 makes the first oil outlet 1004 and the first oil outlet 1003 pass through the first balanced valve 2000 connections.

Second balanced valve 3000, be set to balance valve block 1000 in, the second balanced valve 3000 respectively with the second oil inlet end 1002 are connected with the second oil outlet 1005, and the second balanced valve 3000 is configured to: when oil enters from the first oil inlet end 1001 When one oil outlet 1004, the second balanced valve 3000 makes the second oil outlet 1005 and the second oil inlet end 1002 pass through the second balanced valve 3000 connections.

As a preferable embodiment, balancing valve group further includes the first check valve 4000, the first check valve 4000 Oil inlet is connected to the first oil inlet end 1001, and the oil outlet of the first check valve 4000 is connected to the first oil outlet 1004.Pass through The unilaterally connected that first check valve 4000 realizes the first oil inlet end 1001 and the first oil outlet 1004 is set.

Further, in this embodiment the first balanced valve 2000 include:

First balanced valve oil inlet 2001 is connected to the first oil outlet 1003；

First load port 2002 is connected to the oil outlet of the first oil outlet 1004 and the first check valve 4000 simultaneously；

First control port 2003 is connected to by oil duct with the second oil inlet end 1002.

Further, in this embodiment the second balanced valve 3000 include:

Second balanced valve oil inlet 3001 is connected to the second oil inlet end 1002；

Second load port 3002 is connected to the second oil outlet 1005；

Second control port 3003 is connected to by oil duct with the first oil inlet end 1001.

Further, balance valve group further includes pressure measuring tie-in 5000, and pressure measuring tie-in 5000 passes through oil duct and the first oil inlet end 1001 are connected to the second oil inlet end 1002.

Introduction is made to the flexible principle of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder below:

Due to the above structure, when multistage hydraulic cylinder stretches out, being separately connected into, oil return for hydraulic control system is flat The first oil inlet end 1001, the second oil inlet end 1002 for the valve block 1000 that weighs, oil inlet pass through the first check valve of the first balanced valve 2000 4000 are directly entered the rodless cavity of multistage hydraulic cylinder, and the rod chamber of multistage hydraulic cylinder then passes through 3000 oil return of the second balanced valve, from And multistage hydraulic cylinder is pushed to stretch out.

When multistage hydraulic cylinder is retracted into bottom, level-one rod chamber 403, second level rod chamber 503 and three-level rod chamber 603 are and the The connection of two oil outlets 1005, although the load of multistage hydraulic cylinder is acted directly on cylinder body 300 and three-level piston rod 602, Due to the effect of the first balanced valve 2000,3000 back pressure retention performance of the second balanced valve, so that level-one rod chamber 403, second level have There is pressure in rod cavity 503 and three-level rod chamber 603, level-one rodless cavity 404, second level rodless cavity 504 and three-level rodless cavity 604, And within the scope of payload, which is no more than the setting pressure of 20 first balanced valves 2000, the second balanced valve 3000, First balanced valve 2000, the second balanced valve 3000 are kept closed, ensure that first stage piston 401 and second piston 501 it Between, between second piston 501 and three-level piston 601 keep certain positive pressure.

Therefore it is between first stage piston 401 and second piston 501, between second piston 501 and three-level piston 601 tight Pin-lift arrangement is opened and is kept it turned on by closely connected conjunction state, the cylinder internal check valve 200 in second piston 501, first stage piston Cylinder internal check valve 200 in 401 will be opened by pin-lift arrangement and be kept it turned on, therefore level-one rod chamber 403, second level have Rod cavity 503 is connected to three-level rod chamber 603, hereby it is ensured that the stretching order of hydraulic cylinder is first stage piston bar 402, works as level-one After piston rod 402 is fully extended, after first stage piston 401 encounters guide sleeve, second piston rod 502 stretches out, when second piston rod 502 After fully extended, after second piston 501 encounters guide sleeve, three-level piston rod 602 stretches out.

Due to the above structure, when multistage hydraulic cylinder retracts, being separately connected into, oil return for hydraulic control system is flat Weigh valve block 1000 the second oil inlet end 1002, the first oil inlet end 1001, when hydraulic system high pressure liquid pressure oil by reversal valve into When entering the second oil inlet end 1002, high pressure liquid pressure oil will be directly entered multistage by the second balanced valve 3000 and the second oil outlet 1005 The rod chamber of hydraulic cylinder, driving multistage hydraulic cylinder retract.

High pressure liquid pressure oil into the second oil inlet end 1002 passes through oil duct in balance valve block 1000 simultaneously to enter first flat The spool of first control port 2003 of weighing apparatus valve 2000, the first balanced valve 2000 of driving is opened, and the first balanced valve 2000 will at this time It is connected to the first oil outlet 1004 and the first oil outlet 1003, the hydraulic oil of multistage hydraulic cylinder rodless cavity then passes through the first oil outlet 1004, the first balanced valve 2000 enters the first oil outlet 1003, and directly returns system fuel tank.

Assuming that multistage hydraulic cylinder all stretches out in place, the check valve on first stage piston 401 and second piston 501 is set Component is under spring force for closed state, and level-one rod chamber 403 has with second level rod chamber 503 and three-level at this time Rod cavity 603 is not connected to, therefore three-level piston rod 602 will retract first.After three-level piston rod 602 is fully retracted, three-level is living Plug 601 will be contacted with second piston 501, and the cylinder internal check valve 200 on second piston 501 will be in the effect of pin-lift arrangement at this time Lower unlatching, second level rod chamber 503 will be connected to three-level rod chamber 603, and high pressure liquid pressure oil enters second level rod chamber 503, and second level is living Stopper rod 502 starts to retract.After second piston rod 502 is fully retracted, second piston 501 will be contacted with first stage piston 401, at this time Cylinder internal check valve 200 on first stage piston 401 will be opened under the action of pin-lift arrangement, and level-one rod chamber 403 will have with second level Rod cavity 503 and three-level rod chamber 603 are connected to, and high pressure liquid pressure oil enters level-one rod chamber 403, and first stage piston bar 402 starts to retract. Since multistage hydraulic cylinder is from any one middle position, stretching out or retracting, corresponding state is corresponded to, hereby it is ensured that multistage liquid Cylinder pressure can only be acted by above-mentioned order.

Due to using cylinder internal check valve 200 and pin-lift arrangement, and the bullet of every group of cylinder internal check valve 200 and pin-lift arrangement Spring force does not exceed 100KN, compared with the stroke valve with lance, reduces the interaction force of piston space, to preferably protect The stretching in order of the multistage hydraulic cylinder under negative load effect is demonstrate,proved.Simultaneously because the cracking pressure very little of cylinder internal check valve 200, To guarantee when multistage hydraulic cylinder stretches out, regardless of whether there is random cylinder phenomenon, every one-stage hydraulic cylinder is not in that superpressure is existing As.

The utility model is not limited to above embodiment, for those skilled in the art, not Under the premise of being detached from the utility model principle, several improvements and modifications can also be made, these improvements and modifications are also considered as this reality Within novel protection scope.The content being not described in detail in this specification belongs to well known to professional and technical personnel in the field The prior art.

Claims (10)

1. a kind of piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder characterized by comprising

Cylinder body (300)；

At least piston rod assembly that is arranged step by step of two-stage is set in the cylinder body (300), and every grade of piston rod assembly includes living The piston rod filled in and be fixed on piston, and every grade of piston rod assembly has bar for what the accommodating space where it was divided into corresponding level Chamber and rodless cavity；

Multiple check valve assemblies, each check valve assembly are set to the higher piston rod group of adjacent two-stage piston rod assembly In the piston of part, each check valve assembly includes,

Cylinder internal check valve (200) is used to control the rod chamber connection of adjacent two-stage piston rod assembly or stops；

Pin-lift arrangement is used to that the cylinder internal check valve (200) to be driven to open or close, and the pin-lift arrangement is configured to: When the piston in adjacent two-stage piston rod assembly separates during stretching or retraction, the pin-lift arrangement is self-locking, described Cylinder internal check valve (200) is closed, and the rod chamber of adjacent two-stage piston rod assembly is stopped；Work in adjacent two-stage piston rod assembly When plug contacts during stretching or retraction, the pin-lift arrangement drives the cylinder internal check valve (200) to open, and makes adjacent two The rod chamber connection of grade piston rod assembly；And

Valve group is balanced, is fixed on the piston rod of minimum first stage piston bar assembly, the balance valve group is for having described in controlling The oil inlet or oil return of rod cavity, and the oil inlet or oil return of the control rodless cavity.

2. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as described in claim 1, it is characterised in that: the pin-lift arrangement is at least Part is located at outside piston, after the piston rod assembly of lower level in adjacent two-stage piston rod assembly retracts in place, the mandril dress When part outside setting in piston is by external force, the pin-lift arrangement drives the cylinder internal check valve (200) to open, and makes phase The rod chamber of adjacent two-stage piston rod assembly is connected to.

3. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 2, it is characterised in that: be each equipped with described unidirectional It include two the first oil ducts (102) and the second oil duct (103) along corresponding piston radial setting in the piston of valve module, it is described First oil duct (102) and the second oil duct (103) are connected to a rod chamber of adjacent two-stage piston rod assembly respectively, in the cylinder Check valve (200) is equipped with import (203) and outlet (204), and the import (203) is connected to second oil duct (103), institute Outlet (204) is stated to be connected to first oil duct (102).

4. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 3, it is characterised in that: the pin-lift arrangement packet It includes:

Top stem casing (1), interior to be equipped with the first receiving portion (11), first receiving portion (11) and second oil duct (103) are even It is logical；

First mandril (2) is fixed in the receiving portion (11), and first mandril (2) can be in the first receiving portion (11) it moves back and forth, and passes through the import (203) to drive the cylinder internal check valve (200) to open, and first mandril (2) the second receiving portion (21) are additionally provided with；

Second mandril (3), in second receiving portion (21), second mandril (3) can be in second receiving for setting It is moved back and forth in portion (21), second mandril (3) is at least partially disposed at second receiving portion (21) outside, and second top Bar (3) is axially arranged with through-hole (31) along it；

Locking mechanism (4) is used to open and release first mandril (2) and moves back and forth in first receiving portion (11) Locking, when open locking when, the pin-lift arrangement is self-locking；

First driving device (5) is set in first receiving portion (11), and the first driving device (5) is for driving institute It is mobile towards the direction locked by the locking mechanism (4) to state the first mandril (2)；And

Second driving device (6) is set in second receiving portion (21), and second driving device (6) is for driving institute The second mandril (3) movement is stated, the locking mechanism (4) is made to lock first mandril (2).

5. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 4, which is characterized in that the locking mechanism (4) Include:

Mounting hole (41), along being arranged radially for the first mandril (2), the mounting hole (41) is equipped with steel ball (42)；

First groove (43) is located on the inner wall of the top stem casing (1), and first groove (43) is configured to: when described Steel ball (42) be located at first groove (43) it is interior when, the steel ball (42) is for limiting first mandril (2) described the It is moved back and forth in one receiving portion (11)；

Second groove (44) is located on the outer wall of second mandril (3), and second groove (44) is configured to: working as institute State steel ball (42) be located at second groove (44) it is interior when, first mandril (2) can be past in first receiving portion (11) Return movement.

6. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as described in claim 1, it is characterised in that: the cylinder internal check valve (200) it is configured to: single in the cylinder when the rod chamber pressure of corresponding level is greater than cylinder internal check valve (200) cracking pressure It is voluntarily opened to valve (200).

7. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as described in claim 1, which is characterized in that the piston rod oil inlet is double Acting on multistage hydraulic cylinder includes:

First stage piston bar assembly (400) is set in the cylinder body (300), and the first stage piston bar assembly (400) includes level-one Piston (401) and first stage piston bar (402), the first stage piston (401) and first stage piston bar (402) are by the cylinder body (300) Accommodating space be divided into level-one rod chamber (503) and level-one rodless cavity (404), the first stage piston (401) is equipped with the list To valve module；

Second piston bar assembly (500) is set in the first stage piston bar (402), second piston bar assembly (500) packet Include second piston (501) and second piston rod (502), the second piston (501) and second piston rod (502) are by the level-one The accommodating space of piston rod (402) is divided into second level rod chamber (503) and second level rodless cavity (504), on the second piston (501) Equipped with the check valve assembly；

Three-level piston rod assembly (600) is set in the second piston rod (502), three-level piston rod assembly (600) packet Include three-level piston (601) and three-level piston rod (602), the three-level piston (601) and three-level piston rod (602) are by the second level The accommodating space of piston rod (502) is divided into three-level rod chamber (603) and three-level rodless cavity (604), and the balance valve group is fixed On the three-level piston rod (602).

8. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 7, it is characterised in that:

Be equipped with first through hole on the first stage piston (401), second piston (501) and three-level piston (601), the level-one without Rod cavity (404), second level rodless cavity (504) and three-level rodless cavity (604) pass through the first stage piston (401), second piston (501) It is interconnected with three-level piston (601) first through hole.

9. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 8, it is characterised in that:

It is additionally provided with oil-deflecting rod (700) in the three-level piston rod (602), the three-level piston rod (602) and oil-deflecting rod (700) shape At a ring shaped oil passage (104), described ring shaped oil passage (104) one end is connected to the balance valve group, and the other end has with the three-level Rod cavity (603) connection.

10. piston rod oil inlet Double Acting Telescopic Hydraulic Cylinder as claimed in claim 9, it is characterised in that: the balance valve group packet It includes,

Balance valve block (1000) which is provided with the first oil inlet end (1001), the second oil inlet end (1002) and the first oil outlet (1003), it is additionally provided on the balance valve block (1000) unidirectional with first oil inlet end (1001), the first oil outlet (1003) Connection the first oil outlet (1004) and with unilaterally connected second oil outlet (1005) of second oil inlet end (1002), institute It states the first oil outlet (1004) to be connected with the first through hole of the three-level piston (601), second oil outlet (1005) and institute Ring shaped oil passage (104) are stated to be connected；

First balanced valve (2000), be set to the balance valve block (1000) in, first balanced valve (2000) respectively with institute State the first oil outlet (1003) to be connected with the first oil outlet (1004), first balanced valve (2000) is configured to: when oil from When second oil inlet end (1002) enters the second oil outlet (1005), first balanced valve (2000) makes described first to go out Hydraulic fluid port (1004) is connected to the first oil outlet (1003) by the first balanced valve (2000)；And

Second balanced valve (3000), be set to the balance valve block (1000) in, second balanced valve (3000) respectively with institute State the second oil inlet end (1002) to be connected with the second oil outlet (1005), second balanced valve (3000) is configured to: when oil from When first oil inlet end (1001) enters the first oil outlet (1004), second balanced valve (3000) makes described second to go out Hydraulic fluid port (1005) is connected to the second oil inlet end (1002) by the second balanced valve (3000).