CN202967952U - Rotary control hydraulic system and crane - Google Patents
Rotary control hydraulic system and crane Download PDFInfo
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- CN202967952U CN202967952U CN 201220676718 CN201220676718U CN202967952U CN 202967952 U CN202967952 U CN 202967952U CN 201220676718 CN201220676718 CN 201220676718 CN 201220676718 U CN201220676718 U CN 201220676718U CN 202967952 U CN202967952 U CN 202967952U
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Abstract
The utility model discloses a rotary control hydraulic system and a crane, wherein the disclosed rotary control hydraulic system comprises a pilot oil line, a hydraulic control main reversing valve for controlling the flowing direction and on/off of the main oil line via the pilot oil line, and a buffer valve; the buffer valve is provided with a first working oil opening, a second working oil opening, and a control oil opening for controlling on/off of the first working oil opening and the second working oil opening; when the first working oil opening is communicated with the second working oil opening, the high-pressure section of the main oil line is communicated with an oil return line through the buffer valve and the control oil opening of the buffer valve is communicated with the pilot oil line; and a damper is arranged on the closed loop from the control oil opening to the pilot oil opening. The control oil opening of the buffer valve is communicated with the pilot oil line; the pilot oil source is low-pressure and stable oil source, and unrelated to load pressure; and compared with the buffer valve is communicated with the feedback oil line high in fluctuation in the background art, the buffer valve of the rotary control hydraulic system is protected against the influence of the load fluctuation, and capable of immediately responding to buffering so that the rotary system is steady at start and stop.
Description
Technical field
The utility model relates to technical field of engineering machinery, and particularly hydraulic efficiency pressure system and hoisting crane are controlled in a kind of revolution.
Background technology
The car hosit rotary control system is mainly can held stationary when guarantee starting and stopping, reliable and without impact, be all generally to realize this function by rotary buffering valve.
Please refer to Fig. 1, Fig. 1 is a kind of schematic diagram of controlling hydraulic efficiency pressure system that turns round in prior art.
in Fig. 1, mainly comprise fix-displacement pump, proportional control valve with the three-way pressure compensating device, independently cushion valve 11, proportional control valve is main reversing valve, cushion valve 11 is by pass valve, one actuator port of cushion valve 11 is communicated with oil return line, another actuator port is communicated with the first working connection 13 that is in high pressure or the second working connection 14 that is in high pressure by shuttle valve, the control port of cushion valve 11 is communicated with feedback oil circuit 12, when main reversing valve is positioned at left position or right position, and when being in static state, the built-in pressure of spring cavity that the pressure oil of feedback oil circuit 12 can enter cushion valve 11, the pressure oil of working connection can enter with spring in the chamber, oil pressure and spring force in spring cavity can keep balance to cavity pressure with spring, and spool is passed so that two actuator ports of cushion valve 11 remain open state, the first working connection 13 and the second working connection 14 normally advance, oil return.In addition, the feedback oil circuit 12 that is communicated with cushion valve 11 is provided with damping 15
Start moment, existence due to damping 15, cushion valve 11 spring cavitys are built the pressure time lag, be that spring cavity fails to set up high pressure at short notice, and spring is very fast to the pressure voltage built-up rate in the chamber, the high pressure person between the first working connection 13 and the second working connection 14 can overcome cushion valve 11 interior spring pressures and conducting cushion valve 11, and then is communicated with oil return line, the buffer action when starting with realization.When the spring cavity pressure rise was extremely identical with load, namely at ordinary times at a stalemate to the chamber oil pressure with spring, cushion valve 11 was closed again, returns to static state, working connection normal operation.
Yet there is following technical matters in technique scheme:
The first, the control port of cushion valve 11 is communicated with feedback oil circuit 12, the pressure of feedback oil circuit 12 can fluctuate with the fluctuation of load pressure, and when higher or amplitude was larger when oscillation frequency, cushion valve 11 can't in time respond and cushion, can cause the system pressure fluctuation, external manifestation is shake;
second, when handle returns meta (in Fig. 1, main reversing valve is positioned at meta), working connection at the main reversing valve place by shutoff, because the factors such as the external structure parts such as arm and inertia can cause power element (as rotary motor in Fig. 1) in time to stop, but continue epitrochoidal chamber and the pipeline of rotary motor are compressed under effect of inertia, the one-sided working connection that namely is in high pressure can continue high pressure, correspondingly feed back oil circuit 12 oil pressure also higher, the spring cavity of cushion valve 11 still is in high pressure and closes, can't discharge working connection pressure, can cause the cycle of higher pressure between two working connections, until actuator movement stops, cause shake,
When three, stopping, damping 15 also can cause the pressure of cushion valve 11 spring cavitys in time to discharge, and causes shake.
In view of this, how making the rotary system can be more steady when starting and stopping, be the technical matters that those skilled in the art need to be resolved hurrily.
The utility model content
Core of the present utility model is for providing a kind of revolution to control hydraulic efficiency pressure system and hoisting crane, and this hydraulic efficiency pressure system makes the rotary system can be more steady when starting and stopping.
For solving the problems of the technologies described above, the utility model provides a kind of revolution to control hydraulic efficiency pressure system, and comprise guide's oil circuit, controlled by described guide's oil circuit that working connection flows to and the hydraulic control main reversing valve of break-make, and cushion valve; Described cushion valve has the first actuator port, the second actuator port, and the control port of controlling described the first actuator port, the second actuator port break-make, when described the first actuator port and described the second actuator port conducting, the high pressure section of described working connection is communicated with oil return line by described cushion valve, the described control port of described cushion valve is communicated with guide's oil circuit, and described control port to the path of described guide's oil circuit is provided with damping.
Preferably, the number of described cushion valve is two, described working connection comprises the first working connection and the second working connection between hydraulic control main reversing valve and power element, the first actuator port of two described cushion valves connects respectively described the first working connection and described the second working connection, and the second actuator port of two described cushion valves all is communicated with oil return line; Described hydraulic control main reversing valve has two control ends, and two described control ends are communicated with respectively two described guide's oil circuits, and the control port of two described cushion valves is communicated with respectively two described guide's oil circuits.
Preferably, described working connection comprises the first working connection and the second working connection between hydraulic control main reversing valve and power element, and described hydraulic control main reversing valve has two control ends, and two described control ends are communicated with respectively two described guide's oil circuits; The first actuator port of described cushion valve is communicated with the first working connection or the second working connection by the first shuttle valve, and the second actuator port of described cushion valve is communicated with oil return line, and the control port of described cushion valve is by the one in second shuttle valve connection two described guide's oil circuits.
Preferably, the described control port of described cushion valve is provided with check valve to the path of described guide's oil circuit, and described check valve and described damping are set up in parallel.
Preferably, described damping and described check valve are integrated in one.
Preferably, described hydraulic control main reversing valve is the type three-position four-way valve that surges.
In this utility model, the control port of cushion valve is communicated with guide's oil circuit, pilot control is low pressure and stable oil sources, irrelevant with load pressure, cushion valve is communicated with the larger feedback oil circuit of fluctuation in the background technology, in the utility model, cushion valve is not affected by the fluctuation of load, can in time respond and cushion, so that rotary system is comparatively steady when starting and stopping.And rotary system is when stopping, guide's oil circuit pressure decreased, although one-sided working connection pressure is still higher under effect of inertia, but the pressure in the cushion valve spring cavity can pass through the successfully pressure release of guide's oil circuit, the first actuator port of cushion valve and the second actuator port can keep conducting state, make the working connection of high pressure by the rapid pressure release of cushion valve, thereby also can play pooling feature preferably when stopping.
The utility model also provides a kind of hoisting crane, comprises power element and drives the revolution control hydraulic efficiency pressure system that described power element moves, and it is that hydraulic efficiency pressure system is controlled in the described revolution of above-mentioned any one that hydraulic efficiency pressure system is controlled in described revolution.
Preferably, described power element is rotary motor.
Because above-mentioned revolution control hydraulic efficiency pressure system has above-mentioned technique effect, the hoisting crane with this revolution control hydraulic efficiency pressure system also has identical technique effect.
Description of drawings
Fig. 1 is a kind of schematic diagram of controlling hydraulic efficiency pressure system that turns round in prior art;
Fig. 2 controls the schematic diagram of a kind of specific embodiment of hydraulic efficiency pressure system for the utility model provides revolution;
Fig. 3 controls the schematic diagram of the another kind of specific embodiment of hydraulic efficiency pressure system for the utility model provides revolution.
In Fig. 1:
11 cushion valves, 12 feedback oil circuits, 13 first working connections, 14 second working connections, 15 dampings, P oil inlet, T return opening;
In Fig. 2-3:
21 cushion valves, 211 first actuator ports, 212 second actuator ports, 213 control ports, 221 dampings, 222 check valves, 23 rotary motors, 241 first working connections, 242 second working connections, 25 hydraulic control main reversing valves, 26 guide's oil circuits, 27 first shuttle valves, 28 second shuttle valves, P oil inlet, T return opening
The specific embodiment
Core of the present utility model is for providing a kind of revolution to control hydraulic efficiency pressure system and hoisting crane, and this hydraulic efficiency pressure system makes the rotary system can be more steady when starting and stopping.
In order to make those skilled in the art understand better the technical solution of the utility model, the utility model is described in further detail below in conjunction with the drawings and specific embodiments.
Please refer to Fig. 2, Fig. 2 controls the schematic diagram of a kind of specific embodiment of hydraulic efficiency pressure system for the utility model provides revolution.
Hydraulic efficiency pressure system is controlled in revolution in this embodiment, comprises guide's oil circuit 26, is controlled by guide's oil circuit 26 that working connections flow to and the hydraulic control main reversing valve 25 of break-make.As described in Figure 2, the spool of hydraulic control main reversing valve 25 moves to left or moves to right under guide oil road 26 effects, thereby switches the flow direction or the break-make of working connection between hydraulic control main reversing valve 25 and power element.Hydraulic control main reversing valve 25 in Fig. 2 is three-position four-way valve, it has two control ends, two control ends are communicated with respectively two guide's oil circuits 26, when left side guide's oil circuit 26 pressure raise, be positioned at left position, when guide's oil circuit 26 pressure in right side raise, be positioned at right position, when both sides guide's oil circuit 26 pressure all reduce, be positioned at meta.Three-position four-way valve is suitable for the revolution of this kind closed system and controls needs, can expect that hydraulic control main reversing valve 25 can be also the six logical or pilot-operated type change-over valves of other types.
this revolution is controlled hydraulic efficiency pressure system and is also comprised cushion valve 21, cushion valve 21 is by pass valve, has the first actuator port 211, the second actuator port 212, and control the first actuator port 211, the control port 213 of the second actuator port 212 break-makes, as shown in Figure 2, control port 213 is communicated with spring cavity, spring is communicated with its first actuator port 211 to the chamber, high pressure oil flows to spring cavity and builds through control port 213 and presses and when with spring, the chamber being maintained an equal level, the first actuator port 211 of cushion valve 21 and the second actuator port 212 disconnect, otherwise, the first actuator port 211 and the second actuator port 212 conductings.When the first actuator port 211 and the second actuator port 212 conducting, the high pressure section of working connection can be communicated with oil return line by cushion valve 21.In Fig. 2, working connection comprises the first working connection 241 and the second working connection 242 between rotary motor 23 and hydraulic control main reversing valve 25, when the first working connection 241 is high-pressure oil passage, the high pressure section of working connection is the first working connection 241, when the second working connection 242 switched to high-pressure oil passage, the high pressure section of working connection was the second working connection 242.Namely no matter the first working connection 241 is in high pressure or the second working connection 242 is in high pressure, and the working connection that is in high pressure all can be communicated with oil return lines by cushion valve 21.
In addition, in the present embodiment, the control port 213 of cushion valve 21 is communicated with guide's oil circuit 26.And control port 213 to the path of guide's oil circuit 26 is provided with damping 221, similar with the principles illustrated of background technology, the setting of damping 221 is intended to realize that cushion valve 21 spring cavitys are built is pressed in temporal sluggishness, thereby reaches instantaneous conducting cushion valve 21 and play buffer action.
Further, in this embodiment, the number of cushion valve 21 is two, and as shown in Figure 2, the first actuator port 211 of two cushion valves 21 connects respectively the first working connection 241 and the second working connection 242, and the second actuator port 212 of two cushion valves 21 all is communicated with oil return line.The first working connection 241 is high-pressure oil passage, and when the second working connection 242 was low pressure oil way, the first working connection 241 can by cushion valve 21 bufferings in left side, during commutation, can pass through cushion valve 21 bufferings on right side as the second working connection 242 of high-pressure oil passage.Correspondingly, the control port 213 of two cushion valves 21 is communicated with respectively two guide's oil circuits 26 of both sides.Certainly in order to guarantee that cushion valve 21 can realize pooling feature; the working connection that cushion valve 21 first actuator ports 211 connect is positioned at the same side with guide's oil circuit 26 that its control port 213 is communicated with; when guaranteeing that namely cushion valve 21 is communicated with the working connection of high pressure, its control port 213 is communicated with guide's oil circuit 26 that pressure raises.
In above-described embodiment, hydraulic control main reversing valve 25 to each working connection between power element is realized buffering by independent cushion valve 21, has avoided the interference in the crank motion.And when rotary motor 23 rotated and reverse, general pressure at both sides required different.Such as, in Fig. 2, when the first working connection 241 and the second working connection 242 are in high pressure respectively, the high-pressure demand may be different, and the buffering of cushion valve 21 depends on that spring cavity pressure and spring are to cavity pressure (corresponding working connection pressure), after two cushion valves 21 were set, each cushion valve 21 can be regulated according to the working connection pressure of correspondence, has increased the adjustability of pooling feature.
When two cushion valves 21 is set, the control port 213 of cushion valve 21 can arrange check valve 222 to the path of guide's oil circuit 26, check valve 222 and damping 221 are set up in parallel, be that control port 213 has two paths with guide's oil circuit 26, as shown in Figure 2, the hydraulic oil of guide's oil circuit 26 can flow to control port 213 through damping 221, and in cushion valve 21 spring cavitys, hydraulic oil can flow back to guide's oil circuit 26 through check valve 222 from control port 213.After check valve 222 was set, when rotary system stopped, the hydraulic oil in spring cavity can be back to rapidly 26 pressure releases of guide's oil circuit through check valve 222, rather than through the slow pressure release of damping 221, further improved the buffering effect that stops moment.The damping 221 and the check valve 222 that arrange can be integrated in one, and form one-way damper valve, are convenient to install and simplify piping layout.
Adopt two cushion valves 21 in above-described embodiment, produced technique effect as above, and realized that stable buffering does not arrange two cushion valves 21 and is fine yet.Please refer to Fig. 3, Fig. 3 controls the schematic diagram of the another kind of specific embodiment of hydraulic efficiency pressure system for the utility model provides revolution.This embodiment only arranges a cushion valve 21.
Equally, working connection comprises the first working connection 241 and the second working connection 242 between hydraulic control main reversing valve 25 and rotary motor 23, and hydraulic control main reversing valve 25 has two control ends, and two control ends are communicated with respectively two guide's oil circuits 26.The first actuator port 211 of cushion valve 21 is communicated with the first working connection 241 or the second working connections 242 by the first shuttle valve 27, namely during the first working connection 241 high pressure, when being communicated with the first working connection 241, the second working connection 242 high pressure, is communicated with the second working connection 242.In addition, the second actuator port 212 of cushion valve 21 is communicated with oil return line, 213 one that are communicated with in two guide's oil circuits 26 by the second shuttle valve 28 of the control port of cushion valve 21.
Consistent with above-described embodiment principle, in order to realize pooling feature, when the first actuator port 211 of cushion valve 21 was communicated with the high-pressure main oil path of a side, its control port 213 was communicated with guide's oil circuit 26 of the pressure rising of homonymy.This embodiment is communicated with guide's oil circuit 26 with the control port 213 of cushion valve 21 equally, make the startup of rotary system and stop all accessing effective buffering, reduce and impact, and a cushion valve 21 also can be simplified the hydraulic tubing layout, certainly, compared to above-described embodiment, in this embodiment, the adjustability of cushion valve buffering is taken second place.
When a cushion valve 21 only is set, also can to guide's oil circuit 26, damping arranged side by side 222 and check valve 221 be set in cushion valve 21 control ports 213.As shown in Figure 3, after the hydraulic oil of left side guide's oil circuit 26 enters the spring cavity of cushion valve 21 through left side damping 222, the second shuttle valve 28 left side conductings, spring cavity can pass through the second shuttle valve 28 left side oil circuit oil return pressure releases; Right side guide's oil circuit 26 hydraulic oil are after right side damping 222 enters cushion valve 21 spring cavitys, the second shuttle valve 28 right side conductings, spring cavity can pass through right side oil circuit oil return pressure release, as seen in this embodiment check valve 221 the technique effect that can reach same with above-described embodiment is set.In addition, same as the previously described embodiments, damping 222 and the check valve 221 formation one-way damper valve that can be integrated in one.
Need to prove, for the various embodiments described above, answer the ratio of the area (acting on spring to the chamber) of the area (acting on spring cavity) of guide's oil circuit effect on appropriate design cushion valve 21 and the effect of load oil sources, this ratio is crossed conference and is caused buffering effect bad, and the pressure excess gradient is larger; When the too small meeting of ratio causes heavy duty speed of revolutions not and cal val increase, affect work efficiency.
The utility model also provides a kind of hoisting crane, comprises power element and drives the revolution control hydraulic efficiency pressure system that power element moves, and it is that hydraulic efficiency pressure system is controlled in the described revolution of above-mentioned arbitrary embodiment that hydraulic efficiency pressure system is controlled in described revolution.Because above-mentioned revolution control hydraulic efficiency pressure system has above-mentioned technique effect, the hoisting crane with this revolution control hydraulic efficiency pressure system also has identical technique effect, repeats no more herein.Power element can be specifically rotary motor 23, as shown in Fig. 2,3.
Abovely a kind ofly state that hydraulic efficiency pressure system is controlled in revolution and hoisting crane all is described in detail to provided by the utility model.Used specific case herein principle of the present utility model and embodiment are set forth, the explanation of above embodiment just is used for helping to understand method of the present utility model and core concept thereof.Should be understood that; for those skilled in the art; under the prerequisite that does not break away from the utility model principle, can also carry out some improvement and modification to the utility model, these improvement and modification also fall in the protection domain of the utility model claim.
Claims (8)
1. hydraulic efficiency pressure system is controlled in a revolution, and comprise guide's oil circuit (26), controlled by described guide's oil circuit (26) that working connection flows to and the hydraulic control main reversing valve (25) of break-make, and cushion valve (21); described cushion valve (21) has the first actuator port (211), the second actuator port (212), and control described the first actuator port (211), the control port (213) of the second actuator port (212) break-make, when described the first actuator port (211) and described the second actuator port (212) conducting, the high pressure section of described working connection is communicated with oil return line by described cushion valve (21), it is characterized in that, the described control port (213) of described cushion valve (21) is communicated with guide's oil circuit (26), and described control port (213) to the path of described guide's oil circuit (26) is provided with damping (222).
2. hydraulic efficiency pressure system is controlled in revolution as claimed in claim 1, it is characterized in that, the number of described cushion valve (21) is two, described working connection comprises the first working connection (241) and the second working connection (242) that is positioned between hydraulic control main reversing valve (25) and power element, first actuator port (211) of two described cushion valves (21) connects respectively described the first working connection (241) and described the second working connection (242), and second actuator port (212) of two described cushion valves (21) all is communicated with oil return line; Described hydraulic control main reversing valve (25) has two control ends, and two described control ends are communicated with respectively two described guide's oil circuits (26), and the control port (213) of two described cushion valves (21) is communicated with respectively two described guide's oil circuits (26).
3. hydraulic efficiency pressure system is controlled in revolution as claimed in claim 1, it is characterized in that, described working connection comprises the first working connection (241) and the second working connection (242) that is positioned between hydraulic control main reversing valve (25) and power element, described hydraulic control main reversing valve (25) has two control ends, and two described control ends are communicated with respectively two described guide's oil circuits (26); First actuator port (211) of described cushion valve (21) is communicated with the first working connection (241) or the second working connection (242) by the first shuttle valve (27), second actuator port (212) of described cushion valve (21) is communicated with oil return line, and the control port (213) of described cushion valve (21) is communicated with the one of (26) in two described guide's oil circuits by the second shuttle valve (28).
4. hydraulic efficiency pressure system is controlled in revolution as described in claim 1-3 any one, it is characterized in that, the described control port (213) of described cushion valve (21) is provided with check valve (221) to the path of described guide's oil circuit (26), and described check valve (221) and described damping (222) are set up in parallel.
5. hydraulic efficiency pressure system is controlled in revolution as claimed in claim 4, it is characterized in that, described damping (222) and described check valve (221) are integrated in one.
6. hydraulic efficiency pressure system is controlled in revolution as described in claim 1-3 any one, it is characterized in that, described hydraulic control main reversing valve (25) is the type three-position four-way valve that surges.
7. a hoisting crane, comprise power element and drive the revolution control hydraulic efficiency pressure system that described power element moves, and it is characterized in that, it is that hydraulic efficiency pressure system is controlled in the described revolution of claim 1-6 any one that hydraulic efficiency pressure system is controlled in described revolution.
8. hoisting crane as claimed in claim 7, is characterized in that, described power element is rotary motor (23).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220676718 CN202967952U (en) | 2012-12-10 | 2012-12-10 | Rotary control hydraulic system and crane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220676718 CN202967952U (en) | 2012-12-10 | 2012-12-10 | Rotary control hydraulic system and crane |
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| Publication Number | Publication Date |
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| CN202967952U true CN202967952U (en) | 2013-06-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220676718 Withdrawn - After Issue CN202967952U (en) | 2012-12-10 | 2012-12-10 | Rotary control hydraulic system and crane |
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| Country | Link |
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| CN (1) | CN202967952U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103010980A (en) * | 2012-12-10 | 2013-04-03 | 徐州重型机械有限公司 | Rotary control hydraulic system and crane |
| CN103591075A (en) * | 2013-11-29 | 2014-02-19 | 徐州重型机械有限公司 | Hydraulic control system synchronous with crane and balancing weight hydraulic cylinder and flow control valve |
| CN107859665A (en) * | 2017-11-24 | 2018-03-30 | 张宏伟 | A kind of fluid control pressure valve group |
| CN109707681A (en) * | 2018-11-05 | 2019-05-03 | 中船华南船舶机械有限公司 | A kind of main follow-up hydraulic system of small-sized fore-and-aft gangway |
-
2012
- 2012-12-10 CN CN 201220676718 patent/CN202967952U/en not_active Withdrawn - After Issue
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103010980A (en) * | 2012-12-10 | 2013-04-03 | 徐州重型机械有限公司 | Rotary control hydraulic system and crane |
| CN103010980B (en) * | 2012-12-10 | 2015-05-13 | 徐州重型机械有限公司 | Rotary control hydraulic system and crane |
| CN103591075A (en) * | 2013-11-29 | 2014-02-19 | 徐州重型机械有限公司 | Hydraulic control system synchronous with crane and balancing weight hydraulic cylinder and flow control valve |
| CN107859665A (en) * | 2017-11-24 | 2018-03-30 | 张宏伟 | A kind of fluid control pressure valve group |
| CN109707681A (en) * | 2018-11-05 | 2019-05-03 | 中船华南船舶机械有限公司 | A kind of main follow-up hydraulic system of small-sized fore-and-aft gangway |
| CN109707681B (en) * | 2018-11-05 | 2020-05-22 | 中船华南船舶机械有限公司 | Small-size step bridge owner follow-up hydraulic system |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20130605 Effective date of abandoning: 20150513 |
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| RGAV | Abandon patent right to avoid regrant |