CN204140521U - Hydraulic control circuit, side ladder device and fire-fighting truck - Google Patents

Hydraulic control circuit, side ladder device and fire-fighting truck Download PDF

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Publication number
CN204140521U
CN204140521U CN201420559353.0U CN201420559353U CN204140521U CN 204140521 U CN204140521 U CN 204140521U CN 201420559353 U CN201420559353 U CN 201420559353U CN 204140521 U CN204140521 U CN 204140521U
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CN
China
Prior art keywords
valve
oil
fluid port
hydraulic
hydraulic fluid
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Application number
CN201420559353.0U
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Chinese (zh)
Inventor
欧涛
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长沙中联消防机械有限公司
中联重科股份有限公司
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Priority to CN201420559353.0U priority Critical patent/CN204140521U/en
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Publication of CN204140521U publication Critical patent/CN204140521U/en

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Abstract

The utility model discloses a kind of hydraulic control circuit, the selector valve comprising oil cylinder and be connected with this oil cylinder, this selector valve is had the filler opening be communicated with system oil-way, the return opening be communicated with oil circuit, to be connected to the first hydraulic fluid port of cylinder rod chamber and to be connected to the second hydraulic fluid port of oil cylinder rodless cavity by the second oil circuit by the first oil circuit, when the spool of selector valve is in primary importance, filler opening is communicated with the second hydraulic fluid port, and return opening is communicated with the first hydraulic fluid port; When the spool of selector valve is in the second place, filler opening is communicated with the first hydraulic fluid port, and return opening is communicated with the second hydraulic fluid port; When the spool of selector valve is in meta, filler opening ends, and return opening is all communicated with the second hydraulic fluid port with the first hydraulic fluid port; Hydraulic control circuit also comprises the first one-way valve, and the first one-way valve to be connected in oil circuit and only to allow hydraulic oil to flow back to fuel tank from return opening.This hydraulic control circuit effectively can eliminate the adverse effect of system back pressure to oil cylinder.

Description

Hydraulic control circuit, side ladder device and fire-fighting truck
Technical field
The utility model relates to technical field of hydraulic pressure, particularly, relates to a kind of hydraulic control circuit, a kind of side ladder device with this hydraulic control circuit, and a kind of fire-fighting truck with this side ladder device.
Background technique
In hydraulic system, system back pressure often makes oil cylinder produce misoperation, affects stability and the reliability of oil cylinder operation.
Such as, the jib of existing engineering vehicle, particularly Elevating platform fire truck is provided with side ladder usually, so that personnel can be current by side ladder, such as, can be climbed down by side ladder by the personnel of rescuing.This side ladder is then launched or return by corresponding oil hydraulic circuit.Fig. 1 discloses the oil hydraulic circuit of a kind of fire-fighting truck jib side ladder, as shown in the figure, oil cylinder 1 is for being connected with jib side ladder, the rod chamber 101 of this oil cylinder 1 and rodless cavity 102 by bidirectional hydraulic lock 13 respectively with the first hydraulic fluid port B and the second hydraulic fluid port A hydraulic connecting of selector valve 2, the oil inlet P of selector valve 2 is connected with system oil-way 3, and its oil return inlet T is connected with oil circuit 4.When selector valve 2 is in upper, the second hydraulic fluid port A is communicated with oil inlet P, and the first hydraulic fluid port B is communicated with oil return inlet T, like this, rodless cavity 102 oil-feed of oil cylinder 1, rod chamber 101 is fuel-displaced, and cylinder piston rod is stretched out, and drives side ladder to launch; When selector valve 2 is in bottom, the second hydraulic fluid port A is communicated with oil return inlet T, and the first hydraulic fluid port B is communicated with oil inlet P, and like this, the rodless cavity 102 of oil cylinder 1 is fuel-displaced, and rod chamber 101 oil-feed, makes oil cylinder shrink, and drives side ladder to draw in; When selector valve 2 is in meta, the first hydraulic fluid port B is communicated with oil return inlet T with the second hydraulic fluid port A, oil cylinder 1 locking under the lock function of bidirectional hydraulic lock 13.
When selector valve 2 is in meta, oil cylinder should be locking, but, along with the carrying out of other actions such as vehicle jib elongation, the oil return inlet T place in this oil hydraulic circuit will form back pressure, and this back pressure will arrive bidirectional hydraulic lock place by selector valve, and due to the unlatching of bidirectional hydraulic lock larger, oil cylinder will be made to be formed differential, oil cylinder will stretch out, thus cause the misoperation that side ladder launches.
Model utility content
The purpose of this utility model is to provide a kind of hydraulic control circuit, and this hydraulic control circuit can eliminate the adverse effect that the back pressure that produces in system oil return road produces actuators such as the oil cylinders of system effectively, improves stability and the reliability of operation of oil cylinde.
To achieve these goals, the utility model provides a kind of hydraulic control circuit, the selector valve comprising oil cylinder and be connected with this oil cylinder, this selector valve is had the filler opening be communicated with system oil-way, the return opening be communicated with oil circuit, to be connected to the first hydraulic fluid port of described cylinder rod chamber and to be connected to the second hydraulic fluid port of described oil cylinder rodless cavity by the second oil circuit by the first oil circuit, when the spool of described selector valve is in primary importance, described filler opening is communicated with described second hydraulic fluid port, described return opening and described first hydraulic fluid port; When the spool of described selector valve is in the second place, described filler opening is communicated with described first hydraulic fluid port, and described return opening is communicated with described second hydraulic fluid port; When the spool of described selector valve is in meta, described filler opening cut-off, described return opening is all communicated with the second hydraulic fluid port with described first hydraulic fluid port; Described hydraulic control circuit also comprises the first one-way valve, and this first one-way valve to be connected in described oil circuit and only to allow hydraulic oil to flow back to fuel tank from described return opening.
Like this, the first one-way valve is connected in oil circuit, and this first one-way valve is configured to only allow hydraulic oil to flow back to fuel tank from the return opening of selector valve, thus when selector valve is in meta state, the back pressure produced in oil circuit can by the first non-return valve blocks outside first hydraulic fluid port and the second hydraulic fluid port of selector valve, make back pressure to have influence on oil cylinder, thus effectively improve stability and the reliability of operation of oil cylinde.
Preferably, described hydraulic control circuit also comprises the bidirectional hydraulic be all connected with described first oil circuit and described second oil circuit and locks device.
Preferably, described bidirectional hydraulic locking device is Bidirectional balanced valve group, and wherein, the first equilibrium valve in this Bidirectional balanced valve group is connected on described first oil circuit, and the hydraulic control mouth of the sequence valve in described first equilibrium valve is connected to the second hydraulic fluid port of described selector valve; The second equilibrium valve in this Bidirectional balanced valve group is connected on described second oil circuit, and the hydraulic control mouth of the sequence valve in described second equilibrium valve is connected to the first hydraulic fluid port of described selector valve.
Preferably, the cracking pressure setting value of described bidirectional hydraulic locking device is greater than the cracking pressure value of described first one-way valve.
Preferably, described first equilibrium valve and described second equilibrium valve include the second one-way valve in parallel and described sequence valve.
Preferably, the oil circuit part of the close described oil cylinder of described first oil circuit and/or described second oil circuit is connected with throttle valve.
Preferably, described system oil-way is connected with reduction valve, the drain tap of this reduction valve is communicated with the oil circuit part of the outlet end of described first one-way valve.
In addition, the utility model provides a kind of side ladder device, and this side ladder device comprises side ladder and above-described hydraulic control circuit, and the piston rod of described oil cylinder is articulated with described side ladder.
In addition, the utility model also provides a kind of fire-fighting truck, and this fire-fighting truck comprises jib and above-described side ladder device, and wherein, cylinder body and the described side ladder of described oil cylinder are hinged on described jib respectively.
Other features and advantages of the utility model are described in detail in embodiment part subsequently.
Accompanying drawing explanation
Accompanying drawing is used to provide further understanding of the present utility model, and forms a part for specification, is used from explanation the utility model, but does not form restriction of the present utility model with embodiment one below.In the accompanying drawings:
Fig. 1 is the schematic diagram of the oil hydraulic circuit of existing a kind of fire-fighting truck jib side ladder;
Fig. 2 is the schematic diagram of the hydraulic control circuit that the utility model embodiment provides.
Description of reference numerals
1-oil cylinder, 2-selector valve, 3-system oil-way, 4-oil circuit, 6-first equilibrium valve, 7-second equilibrium valve, 8-first one-way valve, 9-throttle valve, 10-reduction valve, 11-first oil circuit, 12-second oil circuit, 13-bidirectional hydraulic lock, 14-bidirectional hydraulic locking device, T-return opening, P-filler opening, B-first hydraulic fluid port, A-second hydraulic fluid port, 101-rod chamber, 102-rodless cavity.
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described in detail.Should be understood that, embodiment described herein, only for instruction and explanation of the utility model, is not limited to the utility model.
As shown in Figure 2, the hydraulic control circuit that the utility model embodiment provides comprises oil cylinder 1, selector valve 2 and the first one-way valve 8, wherein,
Selector valve 2 is connected with oil cylinder 1, and this selector valve 2 is had the oil inlet P be communicated with system oil-way 3, the oil return inlet T be communicated with oil circuit 4, to be connected to the first hydraulic fluid port B of oil cylinder 1 rod chamber 101 and to be connected to the second hydraulic fluid port A of oil cylinder 1 rodless cavity 102 by the second oil circuit 12 by the first oil circuit 11, when the spool of selector valve 2 is in primary importance, oil inlet P is communicated with the second hydraulic fluid port A, oil return inlet T and the first hydraulic fluid port B; When the spool of selector valve 2 is in the second place, oil inlet P is communicated with the first hydraulic fluid port B, and oil return inlet T is communicated with the second hydraulic fluid port A; When the spool of selector valve 2 is in meta, oil inlet P is ended, and oil return inlet T is all communicated with the second hydraulic fluid port A with the first hydraulic fluid port B; Meanwhile, the first one-way valve 8 to be connected in oil circuit 4 and only to allow hydraulic oil to flow back to fuel tank from oil return inlet T.
Like this, the first one-way valve 8 is connected in oil circuit 4, and this first one-way valve 8 is configured to only allow hydraulic oil to flow back to fuel tank from the oil return inlet T of selector valve 2, thus when selector valve 2 is in meta state, the back pressure that the downstream oil circuit being arranged in the first one-way valve 8 of oil circuit 4 produces is by outside the first hydraulic fluid port B of being blocked in selector valve 2 by the first one-way valve 8 and the second hydraulic fluid port A, this back pressure cannot be had a negative impact to oil cylinder 1, thus effectively improve stability and the reliability of oil cylinder 1 operation.
Further, in order to improve the stability of cylinder action, particularly when selector valve 2 is in meta, improve the reliability of oil cylinder locking, preferably, as shown in Figure 2, described hydraulic control circuit also comprises the bidirectional hydraulic be all connected with the first oil circuit 11 and the second oil circuit 12 and locks device 14, like this, by this bidirectional hydraulic locking device 14, when selector valve 2 is in meta, the hydraulic oil in the rod chamber of oil cylinder and rodless cavity keeps not flowing, thus remains on required state by reliable and stable for piston rod.
This bidirectional hydraulic locking device 14 can be bidirectional hydraulic lock, realizes the locking of oil cylinder.But due to the existence of the first one-way valve, considering and may have certain back pressure between the first hydraulic fluid port B of selector valve and the second hydraulic fluid port A, there is making oil cylinder the possibility forming differential cylinder in bidirectional hydraulic lock.
Therefore, in order to thoroughly avoid this possibility, further improve the reliability of oil cylinder locking, in the preferred mode of execution of one, as shown in Figure 2, bidirectional hydraulic locking device 14 is Bidirectional balanced valve group, wherein, the first equilibrium valve 6 in this Bidirectional balanced valve group is connected on the first oil circuit 11, and the hydraulic control mouth of the sequence valve in the first equilibrium valve 6 is connected to the second hydraulic fluid port A of selector valve 2; And the second equilibrium valve 7 in this Bidirectional balanced valve group is connected on the second oil circuit 12, the hydraulic control mouth of the sequence valve in the second equilibrium valve 7 is connected to the first hydraulic fluid port B of selector valve 2.
Like this, when selector valve is in meta, the piston rod of oil cylinder can be remained on desired location more reliably by the first equilibrium valve 6 of this Bidirectional balanced valve group and the second equilibrium valve 7, now, outside the first hydraulic fluid port B that system back pressure is blocked in selector valve by the first one-way valve 8 and the second hydraulic fluid port A, and/or the back pressure that may exist between the first hydraulic fluid port B of selector valve 2 and the second hydraulic fluid port A, this Bidirectional balanced valve group is not had an impact, thus further improve the reliability of oil cylinder locking.
In addition, oil cylinder piston rod stretch out with in retracting action, the stationarity of cylinder piston rod action can be realized by the first equilibrium valve 6 and the second equilibrium valve 7.
More preferably, in order to prevent having an impact to bidirectional hydraulic locking device 14 during the first one-way valve opens, the cracking pressure setting value of bidirectional hydraulic locking device 14 is greater than the cracking pressure value of described first one-way valve 8.
Such as, when bidirectional hydraulic locking device 14 is Bidirectional balanced valve group, the cracking pressure setting value of the first equilibrium valve 6 is greater than the cracking pressure value of described first one-way valve 8, and the cracking pressure setting value of the second equilibrium valve 7 is greater than the cracking pressure value of described first one-way valve 8.Like this, when the first one-way valve 8 is opened, the first equilibrium valve 6 and the second equilibrium valve 7 can't be opened, thus realize the more reliable locking of oil cylinder.
Further, as shown in Figure 2, the first equilibrium valve 6 and the second equilibrium valve 7 include the second one-way valve in parallel and described sequence valve.By the cooperation of this second one-way valve and sequence valve, oil cylinder action more stably can be realized.
In addition, in order to realize the adjustable of the movement speed of oil cylinder, preferably, the oil circuit part of the close oil cylinder 1 of the first oil circuit 11 and/or the second oil circuit 12 is connected with throttle valve 9.By this throttle valve 9, the movement speed of oil cylinder can be made adjustable, make the action of oil cylinder more steady, and increase the working life of system element.
In addition, in order to realize the adjustable of the movement speed of oil cylinder, preferably, system oil-way 3 is connected with reduction valve 10, the drain tap of this reduction valve 10 is communicated with the oil circuit part being positioned at the outlet side of the first one-way valve 8 of oil circuit 4, preferably, the drain tap of reduction valve 10 is communicated with the oil circuit part of the outlet end of the first one-way valve 8.By this reduction valve 10, the movement speed of oil cylinder can be made adjustable, make the action of oil cylinder more steady, and increase the working life of system element.
In addition, as shown in Figure 2, in hydraulic control circuit of the present utility model, selector valve 2, bidirectional hydraulic locking device 14 (such as Bidirectional balanced valve group) and throttle valve 9 etc. can be configured to the valve assembly of a sheet, certainly, in practice, multiple such flapper valve assembly can be set as required, and be arranged in parallel each other, thus provide and operate more reliably.
In addition, the utility model provides a kind of side ladder device, and this side ladder device comprises side ladder and above-described hydraulic control circuit, and wherein, the piston rod of described oil cylinder is articulated with described side ladder.Like this, by the first one-way valve, system back pressure effectively can be avoided the impact of oil cylinder, thus prevent oil cylinder from producing misoperation, to improve the safety reliability of side ladder in desired location further.
In addition, the utility model also provides a kind of fire-fighting truck, and this fire-fighting truck comprises jib and above-described side ladder device, and wherein, cylinder body and the described side ladder of described oil cylinder are hinged on described jib respectively.
Like this, by comprising the side ladder device of described hydraulic control circuit, the Security of this fire-fighting truck operation can effectively be improved.
Below preferred implementation of the present utility model is described by reference to the accompanying drawings in detail; but; the utility model is not limited to the detail in above-mentioned mode of execution; within the scope of technical conceive of the present utility model; can carry out multiple simple variant to the technical solution of the utility model, these simple variant all belong to protection domain of the present utility model.
It should be noted that in addition, each the concrete technical characteristics described in above-mentioned embodiment, in reconcilable situation, can be combined by any suitable mode.In order to avoid unnecessary repetition, the utility model illustrates no longer separately to various possible compound mode.
In addition, also can carry out combination in any between various different mode of execution of the present utility model, as long as it is without prejudice to thought of the present utility model, it should be considered as content disclosed in the utility model equally.

Claims (9)

1. hydraulic control circuit, the selector valve (2) comprising oil cylinder (1) and be connected with this oil cylinder (1), this selector valve (2) is had the filler opening (P) be communicated with system oil-way (3), the return opening (T) be communicated with oil circuit (4), is connected to first hydraulic fluid port (B) of described oil cylinder (1) rod chamber (101) and is connected to second hydraulic fluid port (A) of described oil cylinder (1) rodless cavity (102) by the second oil circuit (12) by the first oil circuit (11)
When the spool of described selector valve (2) is in primary importance, described filler opening (P) is communicated with described second hydraulic fluid port (A), described return opening (T) and described first hydraulic fluid port (B); When the spool of described selector valve (2) is in the second place, described filler opening (P) is communicated with described first hydraulic fluid port (B), and described return opening (T) is communicated with described second hydraulic fluid port (A); When the spool of described selector valve (2) is in meta, described filler opening (P) ends, and described return opening (T) is all communicated with the second hydraulic fluid port (A) with described first hydraulic fluid port (B); It is characterized in that,
Described hydraulic control circuit also comprises the first one-way valve (8), and this first one-way valve (8) to be connected in described oil circuit (4) and only to allow hydraulic oil to flow back to fuel tank from described return opening (T).
2. hydraulic control circuit according to claim 1, is characterized in that, also comprises the bidirectional hydraulic be all connected with described first oil circuit (11) and described second oil circuit (12) and locks device (14).
3. hydraulic control circuit according to claim 2, is characterized in that, described bidirectional hydraulic locking device (14) is Bidirectional balanced valve group, wherein,
The first equilibrium valve (6) in this Bidirectional balanced valve group is connected on described first oil circuit (11), and the hydraulic control mouth of the sequence valve in described first equilibrium valve (6) is connected to second hydraulic fluid port (A) of described selector valve (2);
The second equilibrium valve (7) in this Bidirectional balanced valve group is connected on described second oil circuit (12), and the hydraulic control mouth of the sequence valve in described second equilibrium valve (7) is connected to first hydraulic fluid port (B) of described selector valve (2).
4. the hydraulic control circuit according to Claims 2 or 3, is characterized in that, the cracking pressure setting value of described bidirectional hydraulic locking device (14) is greater than the cracking pressure value of described first one-way valve (8).
5. hydraulic control circuit according to claim 3, is characterized in that, described first equilibrium valve (6) and described second equilibrium valve (7) include the second one-way valve in parallel and described sequence valve.
6. hydraulic control circuit according to claim 1, it is characterized in that, the oil circuit part of the close described oil cylinder (1) of described first oil circuit (11) and/or described second oil circuit (12) is connected with throttle valve (9).
7. hydraulic control circuit according to claim 1, it is characterized in that, described system oil-way (3) is connected with reduction valve (10), the drain tap of this reduction valve (10) is communicated with the oil circuit part of the outlet end of described first one-way valve (8).
8. a side ladder device, comprises side ladder, it is characterized in that, also comprises the hydraulic control circuit according to any one of claim 1-7, and the piston rod of described oil cylinder is articulated with described side ladder.
9. a fire-fighting truck, comprises jib, it is characterized in that, this fire-fighting truck also comprises side according to claim 8 ladder device, and wherein, cylinder body and the described side ladder of described oil cylinder are hinged on described jib respectively.
CN201420559353.0U 2014-09-26 2014-09-26 Hydraulic control circuit, side ladder device and fire-fighting truck CN204140521U (en)

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CN201420559353.0U CN204140521U (en) 2014-09-26 2014-09-26 Hydraulic control circuit, side ladder device and fire-fighting truck

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Application Number Priority Date Filing Date Title
CN201420559353.0U CN204140521U (en) 2014-09-26 2014-09-26 Hydraulic control circuit, side ladder device and fire-fighting truck

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105545838A (en) * 2015-12-28 2016-05-04 中联重科股份有限公司 Balance valve oil hydraulic circuit
CN105570213A (en) * 2016-03-07 2016-05-11 中冶赛迪工程技术股份有限公司 Spray nozzle regulating hydraulic control system
CN106081960A (en) * 2016-08-31 2016-11-09 济宁元昇机电设备有限公司 Realize the hydraulic wireline winch of braking and clutch simultaneously
CN106348167A (en) * 2016-11-07 2017-01-25 安徽理工大学 Spring single-braking manual control mine monorail crane walking mechanism hydraulic system
CN106395629A (en) * 2016-11-07 2017-02-15 安徽理工大学 Elastic-force and hydraulic-force dual-braking type mining monorail crane pushing mechanism hydraulic system
CN106837926A (en) * 2016-12-28 2017-06-13 长沙中联消防机械有限公司 Hydraulic cylinder, hydraulic circuit and fire fighting truck
CN110950264A (en) * 2019-12-30 2020-04-03 哈尔滨通用液压机械制造有限公司 Hydraulic cylinder device for jack

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105545838A (en) * 2015-12-28 2016-05-04 中联重科股份有限公司 Balance valve oil hydraulic circuit
CN105570213A (en) * 2016-03-07 2016-05-11 中冶赛迪工程技术股份有限公司 Spray nozzle regulating hydraulic control system
CN106081960A (en) * 2016-08-31 2016-11-09 济宁元昇机电设备有限公司 Realize the hydraulic wireline winch of braking and clutch simultaneously
CN106081960B (en) * 2016-08-31 2019-08-23 济宁元昇机电设备有限公司 The hydraulic wireline winch of braking and clutch is realized simultaneously
CN106348167A (en) * 2016-11-07 2017-01-25 安徽理工大学 Spring single-braking manual control mine monorail crane walking mechanism hydraulic system
CN106395629A (en) * 2016-11-07 2017-02-15 安徽理工大学 Elastic-force and hydraulic-force dual-braking type mining monorail crane pushing mechanism hydraulic system
CN106837926A (en) * 2016-12-28 2017-06-13 长沙中联消防机械有限公司 Hydraulic cylinder, hydraulic circuit and fire fighting truck
CN110950264A (en) * 2019-12-30 2020-04-03 哈尔滨通用液压机械制造有限公司 Hydraulic cylinder device for jack

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