CN201636138U - Tandem cylinder stroke control device - Google Patents
Tandem cylinder stroke control device Download PDFInfo
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- CN201636138U CN201636138U CN2010201523704U CN201020152370U CN201636138U CN 201636138 U CN201636138 U CN 201636138U CN 2010201523704 U CN2010201523704 U CN 2010201523704U CN 201020152370 U CN201020152370 U CN 201020152370U CN 201636138 U CN201636138 U CN 201636138U
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Abstract
The utility model discloses a tandem cylinder stroke control device comprising a signal acquisition device, a signal processing device and an oil supplementing-draining hydraulic system, wherein the signal acquisition device comprises two cylinder stroke position collectors arranged in a staggered way so as to form the control area of the cylinder stroke; and the oil supplementing-draining hydraulic system is connected with the signal processing device judging the oil volume state of a communication cavity and controlling the oil supplementing-draining hydraulic system to adjust the oil volume of the communication cavity according to the state by signals. In the device, through setting the control area and adjusting the oil volume of the communication cavity according to the communication state of the communication cavity, the cylinder stroke control precision is improved, and overlong and over-short stroke can be detected. In the adjusting process of the oil volume, the influence of oil volume adjustment on the tandem cylinder pumping is avoided by the method of gradually increasing or reducing oil amount in each pumping cycle.
Description
Technical field
The utility model relates to a kind of travel control device that is applied to the serial oil cylinders of equipment such as concrete pump.
Background technique
Concrete pump is that the to-and-fro motion by two series cylinders realizes concrete uninterrupted pumping.Two series cylinder cylinder diameters, bar footpath is all identical, can keep in theory being synchronized with the movement.
But owing to reasons such as accuracy of manufacturing, load, leakages, can cause two oil cylinders asynchronous, along with the accumulation of time, its synchronization error increases gradually, as does not have control gear, and the system that can increase to can't proper functioning.
On concrete pump, generally adopt and unload the stroke that the die mould damping mechanism is adjusted serial oil cylinders.As shown in Figure 1, rodless cavity 143 UNICOMs of the rodless cavity 123 of first oil cylinder 12 of serial oil cylinders and second oil cylinder 14 become the UNICOM chamber together, the rod chamber 121 of first oil cylinder and the rod chamber of second oil cylinder 14 141 are oil suction chamber, when rod chamber 121 oil-feeds, cylinder rod 125 retreats, and cylinder rod 145 stretches out; When rod chamber 141 oil-feeds, cylinder rod 145 retreats, and cylinder rod 121 stretches out.First oil cylinder 12 is provided with pressure release type damping mechanism 127, the second oil cylinders 14 and is provided with pressure release type damping mechanism 147.The stroke of first oil cylinder 12 equates with the stroke of second oil cylinder 12, also is the stroke of serial oil cylinders, i.e. oil cylinder stroke simultaneously.
But unloading the die mould damping mechanism needs to punch on oil cylinder, therefore its position can not free adjusting, and along with the difference of pressure, flow, cylinder diameter, bar footpath, reversing control system, the cylinder buffer distance is also different, so be difficult to adapt to complex working condition, cause the fault that stroke shortens or stroke is elongated sometimes, cause lubricated not in place or suction variation, this will have a significant impact the antiwear characteristic and the efficient of pumping system.
Patent documentation WO 1990004104A1 has disclosed a kind of control stroke mode of serial oil cylinders, as shown in Figure 2, carrying cylinder to carry out push-pull mode by driving oil cylinder with alternate type compression and induction stroke respectively for two controls, wherein, the mutual filler opening of hydraulic fluid port A, B and the oil outlet of rodless cavity, rod chamber UNICOM becomes the UNICOM chamber, control its additional fluid or drain fluid by three position four-way electromagnetic valve, wherein, hydraulic fluid port P is the repairing mouth, and hydraulic fluid port T is a return opening.It is the piston cap end that pressure oil alternately infeeds driving oil cylinder, and these two interconnected driving sides of rod end, its stroke of piston can be able to balance by the supply and the discharging of hydraulic oil, wherein, the continuous final position signal (being detected by sensor B1, B2, B3, B4) of logic triggers on four end positions of driving oil cylinder piston each other.
When the rod end final position signal of a piston exists, when simultaneously the lid end final position signal of another piston did not exist, hydraulic oil liquid was infeeded, and did not exist when the rod end final position signal of a piston, when the lid end final position signal of another piston existed simultaneously, hydraulic oil liquid was discharged; And when the rod end of two pistons exists simultaneously or do not exist with lid end final position signal, will stop the supply and the discharging of hydraulic oil liquid.
This scheme has several defectives:
(1) control accuracy is limited: under the different pressures effect, the amount that fluid replenishes or discharges has bigger variation, and therefore under identical standard (same induced signal), control accuracy can change bigger.
(2) control range is limited: can not detect the long problem of stroke, only can realize that stroke can too short control.
(3) influence the complete machine performance: wait for that control puts in place if oil cylinder stops, then the pumping number of times of per minute will be subjected to considerable influence, so reduce overall efficiency.
The model utility content
The utility model purpose is to provide the travel control device of the serial oil cylinders that equipment such as concrete pump uses.
For this reason, the utility model provide a kind of serial oil cylinders travel control device, it comprises signal pickup assembly, signal processing apparatus and benefit draining hydraulic system, and wherein, signal pickup assembly comprises two oil cylinder stroke station acquisition devices that are staggeredly arranged with the control area that forms oil cylinder stroke; Mend draining hydraulic system and the fluid volume conditions of judging the UNICOM chamber according to the connected state in the UNICOM chamber of relation of the position between oil cylinder stroke and the control area and serial oil cylinders, and mend the signal processing apparatus signal connection that the fluid volume of draining hydraulic system distich cavity is adjusted according to the fluid volume conditions control in UNICOM chamber.
Further, above-mentioned two oil cylinder stroke station acquisition devices are separately positioned on two oil cylinders of serial oil cylinders.
Further, above-mentioned two oil cylinder stroke station acquisition devices are arranged on of serial oil cylinders simultaneously.
Further, above-mentioned oil cylinder stroke station acquisition device is arranged at cylinder rod chamber.
Further, above-mentioned oil cylinder stroke station acquisition device is arranged at oil cylinder rodless cavity.
Further, above-mentioned benefit draining hydraulic system comprises: with the rod chamber of serial oil cylinders or first solenoid directional control valve and second solenoid directional control valve that links to each other with first solenoid directional control valve of rodless cavity selectivity connection, wherein, the filler opening of second solenoid valve is connected to oil supply system, return opening is connected to low voltage terminal or fuel tank, and the oil outlet of second solenoid directional control valve has with filler opening three kinds of switching states that are connected, are connected with return opening and all disconnect with filler opening and return opening.
Can also comprise Proportional valve or servovalve in the above-mentioned benefit draining hydraulic system, so that repairing flow or draining flow are controlled.
In the utility model, by oil cylinder stroke is controlled in the control area, and adjust the fluid volume in UNICOM chamber according to the connected state in UNICOM chamber, its Stroke Control precision is improved, and can detect stroke is long and too short.In the adjustment process of fluid volume, adopt the method that in each pumping circulation, increases or reduce the fluid amount one by one, avoided fluid volume adjustment work to give the influence that serial oil cylinders pumping work is brought, to guarantee overall efficiency.
Except purpose described above, feature and advantage, the utility model also has other purpose, feature and advantage.With reference to figure, the utility model is described in further detail below.
Description of drawings
Constitute this specification a part, be used for further understanding accompanying drawing of the present utility model and show preferred embodiment of the present utility model, and be used for illustrating principle of the present utility model with specification.Among the figure:
Fig. 1 shows having of prior art and unloads the schematic representation of die mould damping mechanism with the serial oil cylinders of adjustment oil cylinder stroke;
Fig. 2 shows the schematic representation that collection piston rod terminal signaling is adjusted the concrete pump of oil cylinder stroke that passes through of prior art;
Fig. 3 shows the theory diagram according to serial oil cylinders travel control device of the present utility model;
Fig. 4 shows a kind of schematic layout pattern according to the signal pickup assembly of the travel control device of the utility model serial oil cylinders;
Fig. 5 shows the another kind of schematic layout pattern according to the signal pickup assembly of the travel control device of the utility model serial oil cylinders; And
Fig. 6 shows the theory diagram according to the benefit draining hydraulic system of the travel control device of the utility model serial oil cylinders.
Embodiment
Below in conjunction with accompanying drawing embodiment of the present utility model is elaborated, but the multitude of different ways that the utility model can be defined by the claims and cover is implemented.
Fig. 3 shows the theory diagram according to the travel control device of serial oil cylinders of the present utility model.As shown in the figure, travel control device comprises signal pickup assembly 10, benefit draining hydraulic system 20 and the signal processing apparatus 30 of oil cylinder stroke.Signal pickup assembly 10 comprise two stagger relatively install near switch, promptly before near switch and back near switch; Signal processing apparatus 30 1 ends link to each other with hydraulic system, and the other end links to each other with the relative signal pickup assembly that staggers 10; Mending draining hydraulic system 20 links to each other with serial oil cylinders UNICOM chamber.
Wherein, signal pickup assembly can be loaded on cylinder rod chamber or oil cylinder rodless cavity or the water tank, or other can detect the place of piston or piston rod position.
Fig. 4 and Fig. 5 show two kinds of partial schematic diagrams according to the signal pickup assembly of the travel control device of serial oil cylinders of the present utility model.As shown in Figure 4 and Figure 5, concrete cylinder 11,13 is used for delivering concrete, water tank 15 is in order to cooling and replacing component space is provided, and oil cylinder 12,14 is a pumping system actuator, and commutation signal generator 16,17 is used to control the pumping system commutation and keeps continuous firing.
In Fig. 4, travel position collector 18 is used to detect the stroke of oil cylinder 12, and its position is forward; Travel position collector 19 is used to detect the stroke of oil cylinder 14, after its position is leaned on, when travel position collector 18,19 when constituting near switch, near switch, 19 of travel position collectors were called the back near switch before travel position collector 18 was called.
In Fig. 5, travel position collector 18,19 is used to detect the stroke of same oil cylinder, and it one in front and one in back is provided with.
The movement process and the stroke of oil cylinder 12 and oil cylinder 14 are identical, travel position collector 18,19 is respectively applied for when detecting two oil cylinder strokes (as shown in Figure 4), when commutation signal generator 16,17 breaks down, can be used as the commutation signal generator and use, so can increase the functional reliability of concrete pump.
In addition, two assemblings near the switching position are to change according to different requirements, therefore do not make qualification, have just provided for example, just precision.Technician in the industry can make adjustment according to own needs.
Fig. 6 shows the theory diagram according to the benefit draining hydraulic system of the travel control device of the utility model serial oil cylinders.As shown in Figure 6, mend draining hydraulic system 20 and comprise two solenoid directional control valves 21 and three-position electromagnetic selector valve 22 and oil supply system 23.
Wherein, serial oil cylinders be communicated with the oil outlet A that the UNICOM chamber constitute is connected to two solenoid directional control valves 21 by rodless cavity, serial oil cylinders be communicated with the oil outlet B that the UNICOM chamber constitute is connected to two solenoid directional control valves 21 by rod chamber, the filler opening of two position switching valves 21 is communicated with the oil outlet A of three position directional valve, the return opening shutoff, according to the UNICOM chamber is rodless cavity or rod chamber, and electromagnet T1a has dead electricity and gets electric two states.Wherein, rodless cavity is corresponding to low-pressure state, and rod chamber is corresponding to high pressure conditions.
The oil outlet B shutoff of three position directional valve, oil inlet P connects oil supply system 23, and the oil return inlet T connected tank is with oil return.Three kinds of states of electromagnet T2a and T2b control three-position electromagnetic selector valve 22: fluid infusion state, draining state and the also state of draining not of repairing neither.
The stroke control method of serial oil cylinders is as follows: form a control area by two travel position collectors that stagger relatively, control the benefit draining state of communicated cavity by judging the oil cylinder stroke and the relation in this zone, with the control of realization oil cylinder stroke.
Particularly, can judge the fluid volume conditions in UNICOM chamber, in conjunction with the control of two solenoid valves 21,22, realize that the fluid volume of distich cavity is controlled, thereby the control oil cylinder stroke be a pumping stroke by the logical relation of travel position collector 18,19.
The controlling method of above-mentioned travel control device is made up of two-part: state is judged, controlled quentity controlled variable is calculated.
One, state is judged
The state of oil cylinder stroke mainly comprises three kinds: not put in place be oil cylinder stroke no show control area, to put in place be that oil cylinder stroke is positioned at the control area, crosses that to put in place be that oil cylinder stroke surpasses the control area.
Before and after on the water tank, can distinguish above three kinds of situations near the layout of switch.
Judgment mode: after two pumping circulation are finished, before and after the statistics near the RST of switch: two all do not have signal-----do not put in place near switch; Before have near switch that then------puts in place near the switch no signal; Two all have signal near switch, and------crossed and put in place.
As shown in Figure 5, if oil cylinder is return, signal is not all sensed near switch 18,19 in front and back, then oil cylinder stroke is just short (not putting in place), if but signal is all sensed near switch 18,19 in front and back, then oil cylinder stroke is just long (cross and put in place), in the utility model, wish just in time to be in after oil cylinder is return these two near between the switch, so just be called " putting in place ".
UNICOM's chamber oil mass state judgment mode: during low pressure, oil cylinder UNICOM chamber is a rodless cavity; During high pressure, oil cylinder UNICOM chamber is a rod chamber.
Relation between the fluid volume in UNICOM chamber and the state that stroke puts in place as shown in Table 1.
Table one:
Two, controlled quentity controlled variable is calculated
The aperture of imitating Proportional valve by the opening time of control switch solenoid valve changes, and realizes the meticulous control of distich cavity fluid.Whole control process is made up of two-part:
(1) original state is determined:
A) UNICOM chamber fluid is too much: draining, open solenoid valve 22, and the endurance is t second, promptly electromagnet T2a gets electric t second;
B) UNICOM chamber fluid is very few: repairing, open solenoid valve 22, and endurance t second, promptly the T2b electromagnet gets electric t second.
Only the determining of above original state value finished during pumping circulation in the first time, determined the approximate algorithm initial value, and this approximate algorithm will be described below.
(2) process values approaches: during when oil cylinder stroke no show control area or above the control area, increase repairing amount or dredge oil amount one by one in ensuing each pumping circulation, be positioned at the control area up to oil cylinder stroke.Remove primary all pumping circulation,, keep repairing of last one-period or draining state constant when UNICOM's chamber fluid occurring when neither too much nor too little.
The embodiment of the specific algorithm of repairing or draining
Table two has provided and increased progressively the identical repairing amount of coefficient or the example of vent flow in each pumping circulation, promptly according to the derive state of the n time pumping circulation of the state of the n-1 time pumping circulation.
Table two
After the t value is less than 100ms, the state counter-rotating.Be that the repairing state becomes draining, the draining state becomes repairing, resets initial value t, and then approaches again according to above algorithm.
It will be understood by those skilled in the art that above numerical value such as t=100ms, numerical value K1=1.2; K2=1.1 etc. are for example, can set as required.
By above description as can be seen, in the utility model, by oil cylinder stroke is controlled in the control area, and adjust the fluid volume in UNICOM chamber according to the connected state in UNICOM chamber, its Stroke Control precision is improved, and can detect stroke is long and too short.In the adjustment process of fluid volume, adopt the method that in each pumping circulation, increases or reduce the fluid amount one by one, with the influence of reduction, thereby improve overall efficiency to serial oil cylinders pumping number of times.
Be preferred embodiment of the present utility model only below, be not limited to the utility model, for a person skilled in the art, the utility model can have various changes and variation.All within spirit of the present utility model and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.
Claims (6)
1. the travel control device of a serial oil cylinders is characterized in that, comprises signal pickup assembly, signal processing apparatus and benefit draining hydraulic system, wherein
Described signal pickup assembly comprises two oil cylinder stroke station acquisition devices that are staggeredly arranged with the control area that forms oil cylinder stroke;
Described benefit draining hydraulic system and the fluid volume conditions of judging described UNICOM chamber according to the connected state in the UNICOM chamber of relation of the position between oil cylinder stroke and the described control area and described serial oil cylinders and then control the described signal processing apparatus signal that described benefit draining hydraulic system adjusts the fluid volume in described UNICOM chamber according to the fluid volume conditions in described UNICOM chamber and be connected.
2. the travel control device of serial oil cylinders according to claim 1 is characterized in that, described two oil cylinder stroke station acquisition devices are separately positioned on two oil cylinders of described serial oil cylinders.
3. the travel control device of serial oil cylinders according to claim 1 is characterized in that, described two oil cylinder stroke station acquisition devices are arranged on of described serial oil cylinders simultaneously.
4. according to the travel control device of claim 2 or 3 described serial oil cylinders, it is characterized in that described oil cylinder stroke station acquisition device is arranged at cylinder rod chamber.
5. according to the travel control device of claim 2 or 3 described serial oil cylinders, it is characterized in that described oil cylinder stroke station acquisition device is arranged at oil cylinder rodless cavity.
6. the travel control device of serial oil cylinders according to claim 1, it is characterized in that, described benefit draining hydraulic system comprises: with the rod chamber of described serial oil cylinders or first solenoid directional control valve and second solenoid directional control valve that links to each other with described first solenoid directional control valve of rodless cavity selectivity connection, wherein, the filler opening of described second solenoid valve is connected to oil supply system, return opening is connected to low voltage terminal or fuel tank, and the oil outlet of described second solenoid directional control valve has with described filler opening and is connected, be connected with described return opening, and three kinds of switching states that all disconnect with described filler opening and return opening.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010201523704U CN201636138U (en) | 2010-03-24 | 2010-03-24 | Tandem cylinder stroke control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010201523704U CN201636138U (en) | 2010-03-24 | 2010-03-24 | Tandem cylinder stroke control device |
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| CN201636138U true CN201636138U (en) | 2010-11-17 |
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| CN2010201523704U Expired - Lifetime CN201636138U (en) | 2010-03-24 | 2010-03-24 | Tandem cylinder stroke control device |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101776107A (en) * | 2010-03-24 | 2010-07-14 | 长沙中联重工科技发展股份有限公司 | Exact stroke control method and stroke control device of serial oil cylinders |
| CN102330715A (en) * | 2011-07-14 | 2012-01-25 | 长沙中联重工科技发展股份有限公司 | Concrete pumping equipment, serial oil cylinder and stroke self-adaptive tail end compensation method thereof |
| WO2014000378A1 (en) * | 2012-06-28 | 2014-01-03 | 中联重科股份有限公司 | Concrete pumping device, and travel control apparatus and method for series oil cylinder |
| CN103591006A (en) * | 2013-11-18 | 2014-02-19 | 中联重科股份有限公司 | Pumping stroke optimal control method and system and engineering machine |
| CN104832476A (en) * | 2014-12-19 | 2015-08-12 | 北汽福田汽车股份有限公司 | Pumping hydraulic system |
| CN105750522A (en) * | 2016-03-18 | 2016-07-13 | 重庆瑞通实业有限公司 | Double-cylinder for vacuumizing control |
-
2010
- 2010-03-24 CN CN2010201523704U patent/CN201636138U/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101776107A (en) * | 2010-03-24 | 2010-07-14 | 长沙中联重工科技发展股份有限公司 | Exact stroke control method and stroke control device of serial oil cylinders |
| WO2011116702A1 (en) * | 2010-03-24 | 2011-09-29 | 长沙中联重工科技发展股份有限公司 | Tandem hydraulic cylinders and stroke control device and method thereof |
| CN101776107B (en) * | 2010-03-24 | 2012-05-30 | 中联重科股份有限公司 | Exact stroke control method and stroke control device of serial oil cylinders |
| CN102330715A (en) * | 2011-07-14 | 2012-01-25 | 长沙中联重工科技发展股份有限公司 | Concrete pumping equipment, serial oil cylinder and stroke self-adaptive tail end compensation method thereof |
| WO2013007061A1 (en) * | 2011-07-14 | 2013-01-17 | 长沙中联重工科技发展股份有限公司 | Concrete pumping device, series cylinder and stroke end adaptive compensation method thereof |
| CN102330715B (en) * | 2011-07-14 | 2013-03-27 | 中联重科股份有限公司 | Concrete pumping equipment, serial oil cylinder and stroke self-adaptive tail end compensation method thereof |
| WO2014000378A1 (en) * | 2012-06-28 | 2014-01-03 | 中联重科股份有限公司 | Concrete pumping device, and travel control apparatus and method for series oil cylinder |
| CN103591006A (en) * | 2013-11-18 | 2014-02-19 | 中联重科股份有限公司 | Pumping stroke optimal control method and system and engineering machine |
| CN103591006B (en) * | 2013-11-18 | 2015-08-12 | 中联重科股份有限公司 | A kind of pumping stroke optimal control method, system and engineering machinery |
| CN104832476A (en) * | 2014-12-19 | 2015-08-12 | 北汽福田汽车股份有限公司 | Pumping hydraulic system |
| CN105750522A (en) * | 2016-03-18 | 2016-07-13 | 重庆瑞通实业有限公司 | Double-cylinder for vacuumizing control |
| CN105750522B (en) * | 2016-03-18 | 2018-12-11 | 重庆瑞通实业有限公司 | For vacuumizing double oil cylinders of control |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee | ||
| CP03 | Change of name, title or address |
Address after: 410013 Yuelu District, Hunan, silver basin Road, No. 361, No. Patentee after: Zoomlion Heavy Industry Science & Technology Development Co., Ltd. Address before: 410013 No. 361 South silver basin, Hunan, Changsha Patentee before: Chang Sha Zoomlion Heavy Industry Science & Technology Development Co., Ltd. |
|
| AV01 | Patent right actively abandoned |
Granted publication date: 20101117 Effective date of abandoning: 20120530 |