CN202667047U - Double-flowmeter digitization spraying system for robot - Google Patents
Double-flowmeter digitization spraying system for robot Download PDFInfo
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- CN202667047U CN202667047U CN 201220140707 CN201220140707U CN202667047U CN 202667047 U CN202667047 U CN 202667047U CN 201220140707 CN201220140707 CN 201220140707 CN 201220140707 U CN201220140707 U CN 201220140707U CN 202667047 U CN202667047 U CN 202667047U
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Abstract
A double-flowmeter digitization spraying system for a robot consists of a fluid part, an airway part and a control part. A circulation feeding mode is adopted in the fluid part. Digital flowmeters are respectively in tandem connection with the inside of a feeding pipeline and a feeding back pipeline to achieve real-time detection of feeding flow and feeding back flow. A pneumatic proportional valve is further in tandem connection with the inside of the feeding pipeline to achieve long-distance flow adjustments. The airway part is divided into six ways in total to provide compressed air for each pneumatic component. An electric proportional valve is in tandem connection with the inside of each airway to achieve long-distance adjustments. The control part is composed of an upper computer and a programmable logic controller (PLC) and is respectively connected with the electric proportional valves and the flowmeters. The double-flowmeter digitization spraying system can achieve real-time flow detection and closed-loop control of a spray gun in a circulation feeding mode, also has the ability of long-distance adjustments of a coating pump, a stirrer, a spray gun switch, atomizing air and fan width air, and is particularly suitable for occasions that an in-gun circulation mode is used for feeding but manual detection of flow is inconvenient or the phenomenon of flow attenuation occurs easily.
Description
Technical field
The utility model relates to a kind of robot with two-flow meter formula digitlization paint finishing, belongs to the Control During Paint Spraying by Robot technical field.
Background technology
At present, industrial products are more and more higher to coating surface quality requirement and the film thickness required precision of Control During Paint Spraying by Robot, under the sufficiently high prerequisite, the bottleneck that constraint spraying operation quality further improves is the flow control accuracy of spray robot in robot motion's precision.But common constant pressure type paint finishing can't to the Real-Time Monitoring in addition of the flowed fluctuation in the spraying operation, more lack effective remote adjustment means.Therefore, can detect in real time automatic spraying system with remote adjustment to gun traffic in the urgent need to a kind of.
Find by the investigation to published document, patent, industrial products, the technological means that gun traffic detects, regulates in the existing paint finishing has three kinds:
The first, manual method.Detection method is: the feeding system of opening spray robot, regulate pressure regulator valve to certain specified pressure value, then close atomizing air and the fan width of cloth air of spray gun, open spray gun, under spray gun, connect certain hour (such as 1 minute) by the hand-held survey tool (such as graduated cylinder) of staff, then read graduated cylinder numerical value, the unit interval discharge-amount of conversion spray gun.Further, if need adjust flux, way is: if current to record flow value higher, then reduce pressure regulator valve pressure; Otherwise, then improve pressure regulator valve pressure.Above-mentioned detection, adjustment process need be carried out repeatedly, until gun traffic reaches requirement, then can begin spraying operation.The shortcoming of this method is apparent: need a large amount of artificial participations, reduced the automaticity of spraying operation, be unfavorable for bringing into play that robot is efficient, the characteristics of automation.And for easy precipitated coating or long size feeding pipeline, coating easily deposits in pipeline, causes gun traffic decay or unstable, cause the staff must not be irregular, monitoring repeatedly regulates gun traffic, bother very much.
The second is controlled by the measurement gear pump.As shown in Figure 1, the method need to adopt the cecum feeding style, and namely spray gun only connects a feed pipe, then at measurement gear pump of feed pipe serial connection.The principle of gear pump is to rotate drive coating by gear to flow, and the coating content that every rotation fixed angle is sent is equal to, and therefore can realize the Detection ﹠ Controling of spray gun ejection flow by the rotating speed of controller control gear pump.The shortcoming of this technology is to be only applicable to the coating induction system that spray gun is cecum, if pipeline is the feeding cycle type, then can flow back to container for paint via return duct by some coating, causes the output flow of gear pump greater than the actual discharge flow of spray gun.In addition, the cost of measurement gear pumping system is high and easy to wear, needs periodic calibrating, and use cost is very high.
The third is controlled by flowmeter and choke valve.As shown in Figure 2, the method limits equally spray gun and only connects a feed pipe, and then at feed pipe serial connection choke valve and flowmeter, when flowmeter detected flow deviation is arranged, controller came adjust flux by the aperture that changes choke valve.The shortcoming of these class methods is identical with the Equations of The Second Kind method, namely being only applicable to spray gun is the pipeline type of cecum, because if pipeline is the feeding cycle type, then because a part of coating flows back to container for paint by return duct, the actual flow that the detected flow of flowmeter sprays greater than spray gun.In addition, the method need to be arranged in flowmeter on the mechanical arm of as close as possible spray gun, has increased size and the weight of mechanical arm tail end, is not suitable for small-sized or the inner surface spray robot.
In sum, the automatic detection of gun traffic and adjusting are all for cecum feed mode in the present paint finishing, yet for a lot of high solids, large proportion, easy precipitated coating, mode that but must feeding cycle, namely connect a return duct at spray gun, make coating constantly circulation between container for paint and spray gun, to prevent the coating precipitation.In this case, during the spray gun shooting, a part of coating sprays from the spray gun spout, a part is back to container for paint from the feed back pipe, existing technological means can't detect has on earth from the ejection of spray gun spout for how much coating, more can't control, and can only be forced to adopt the mode of manual measurement.
In addition, in the existing paint finishing, many pneumatic components and parts (such as pump, agitator etc.) still adopt the control method of " manual pressure regulating valve+Pressure gauge ", and by manually regulating, automaticity is low, can't realize operated from a distance.
Therefore, a kind ofly can the flow of automatic spray gun under the feeding cycle pattern be carried out in real time in the urgent need to developing, detect online and closed-loop control, and pneumatic components and parts are realized the digitlization paint finishing of Long-distance Control, in order to improve the automaticity of paint finishing, improve the operation quality of spray robot.
The utility model content
Problem to be solved in the utility model is to overcome existing robot and regulates the defective that exists with gun traffic Detection ﹠ Controling in the paint finishing, air pressure, develop a kind of robot with online, real-time traffic detectability and long-range coating, air handling capacity with two-flow meter formula digitlization paint finishing, make it to can be used for being not easy to the manual detection flow and must use the feeding cycle pattern to carry out the occasion of feed.
The technical scheme that its technical problem that solves the utility model adopts is:
Robot is comprised of fluid section, air path part, control section with two-flow meter formula digitlization paint finishing, it is characterized in that:
Control section comprises host computer 301 and the PLC controller 302 that contains control program, feed pipe digital flowmeter 108 links to each other with the pulse signal acquisition module of PLC controller 302 by control circuit respectively with feed back pipe digital flowmeter 110, six electric Proportion valves link to each other with the D/A module of PLC controller 302 by control circuit respectively, and PLC controller 302 links to each other with host computer 301 by control circuit.
Described host computer 301 adopts industrial computer or touch-screen.
Described feed pipe digital flowmeter 108 and feed back pipe digital flowmeter 110 adopt intrinsic safety formula digital flowmeter.
Described electric Proportion valve and PLC controller 302 all place in the explosion proof control case 005.
Described paint pump 103 adopts membrane pump, piston pump or gear pump.
Described automatic spray gun 109 adopts the automatic air spray gun.
Compared with the prior art the utility model has the following advantages and the high-lighting effect:
For the automatic spray gun that is connected to simultaneously charging and two coating pipes of feed back, realized that by the mode that detects simultaneously charging and two coating pipes of feed back real-time traffic the real-time, online of spray gun discharge flow detects.Further, realize the closed-loop control of gun traffic, greatly improved the flow control accuracy of paint finishing, eliminated the flowed fluctuation in the spraying process, be conducive to improve the coating quality of robot.In addition, native system has also been realized remote monitoring and the adjusting of pump, agitator, switch rifle, atomization air pressure and fan width of cloth air pressure, has improved the automaticity of paint finishing.
The utility model is specially adapted to be not easy to the manual detection flow and must uses circulation pattern in the rifle to carry out the occasion of feed, and because using high solid, large proportion, easily precipitated coating or the long occasion that the flux depression phenomenon easily occurs of coating transfer pipeline.
Description of drawings
Fig. 1 is the schematic diagram of measurement gear pump formula coating material supply system.
Fig. 2 is the schematic diagram of " flowmeter+choke valve " formula coating material supply system.
Fig. 3 is system architecture schematic diagram of the present utility model.
Among the figure:
The 001-feeding pipe; 002-feed back pipeline; The 003-air pipe line; The 004-control circuit; The 005-anti-explosion cabinet; 006-deathtrap markings;
The 101-container for paint; The 102-agitator; 103; Paint pump; The 104-paint filter; The 105-voltage-stablizer; 106; Pressure regulator valve; 107; Pneumatic proportional valve; 108-feed pipe digital flowmeter; The 109-automatic spray gun; 110-feed back pipe digital flowmeter; The 111-counterbalance valve; The 112-gear pump; The 113-choke valve.
The 201-source of the gas; The 202-air cleaner; 203-the first electric Proportion valve; 204-the second electric Proportion valve; 205-the 3rd electric Proportion valve; 206-the 4th electric Proportion valve; 207-the 5th electric Proportion valve; 208-the 6th electric Proportion valve; The 209-oil sprayer;
The 301-host computer; 302-PLC controller (containing pulse signal acquisition module and D/A module); The 303-controller.
The specific embodiment
Below in conjunction with accompanying drawing structure of the present utility model, principle and the course of work are further specified.
1. the concrete structure of paint finishing
As shown in Figure 3, paint finishing of the present utility model is comprised of fluid section, air path part, control section, it is characterized in that:
Control section comprises host computer 301 and the PLC controller 302 that contains control program, feed pipe digital flowmeter 108 links to each other with the pulse signal acquisition module of PLC controller 302 by control circuit respectively with feed back pipe digital flowmeter 110, six electric Proportion valves link to each other with the D/A module of PLC controller 302 by control circuit respectively, and PLC controller 302 links to each other with host computer 301 by control circuit.
Described host computer 301 can adopt the control computer of robot, also can adopt separately touch-screen, considers the requirement of explosion proof of spray painting operation, and host computer 301 must be placed in outside the deathtrap markings 006, isolates with the paint spray booth.
Described feed pipe digital flowmeter 108 and feed back pipe digital flowmeter 110 adopt intrinsic safety formula digital flowmeter, such as GRACO gear type flowmeter, it detects principle is that flowmeter inside has a pair of intermeshing gear, driven gear rotated when coating was flowed through flowmeter, the every rotation certain angle of gear is then exported a pulse signal, and the pulse signal of receiving in the signal picker statistics certain hour can calculate the coating flow of the flowmeter of flowing through.The accuracy of detection of this type flowmeter is high, and not to be subjected to the impact of dope viscosity, proportion, amount of solid content and temperature, its resolution ratio be 0.012cc/pulse, namely whenever flows through the coating of 0.012cc, then pulse signal of flowmeter output.
Described electric Proportion valve can be selected the FESTO proportional pressure-reducing valve, and controller 302 is selected the PLC with pulse signal acquisition module and D/A module, considers the requirement of explosion proof of spraying operation, and electric Proportion valve and PLC controller 302 all place in the explosion proof control case 005.
Described paint pump 103 can adopt the pneumatic diaphragm pump of GRACO company, have volume little, easy for installation, be applicable to the good characteristics such as medium-high viscosity and larger particles liquid, also can adopt according to actual needs other pumps such as piston pump and gear pump.
Described automatic spray gun 109 adopts LVMP type automatic air spray guns, also can adopt the automatic air spray gun of the other types such as HVLP.
2. the operation principle of paint finishing
Utilize the two-flow meter to the concrete principle that the real-time traffic of non-cecum spray gun carries out Detection ﹠ Controling to be in the utility model: at first, measure the real-time traffic of feed pipe in the feed pipe digital flowmeter 108 of feeding pipe 001 by going here and there, measure the real-time traffic of feed back pipe in the feed back pipe digital flowmeter 110 of feed back pipeline 002 by going here and there, and the two is passed to controller 302, controller 302 obtains the real-time discharge flow of spray gun by the difference of calculating the two; Then, controller 302 compares spray gun real-time traffic and preset flow, then export control signal and regulate its valve port opening to the 3rd electric Proportion valve 205, the air pressure of the 3rd electric Proportion valve 205 outputs is gone here and there the valve port opening of the pneumatic proportional valve 107 in feeding pipe 001 as control signal control again, regulate pressure and the flow of feeding pipe 001, finally reach the purpose of control gun traffic.
(1) two-flow meter formula flow detection principle
Carry out feed owing to adopting the feeding cycle pattern, what feed pipe digital flowmeter 108 collected is the feed pipe flow signal, and what feed back pipe digital flowmeter 110 collected is feed back pipe flow signal, so by the volume invariability of fluid as can be known, gun traffic is the difference of the two, namely has
Q
Rifle=Q
1-Q
21
Q wherein
RifleBe gun traffic, Q
1Be the flow that feed pipe digital flowmeter 108 measures, Q
2The flow that measures for feed back pipe digital flowmeter 110.Obviously, gun traffic is 0 when not spraying, Q when namely spray gun is not shot
1=Q
2
(2) operation principle of flow-control
For satisfying requirement of explosion proof, adopt electric Proportion valve to add two stage control methods of pneumatic proportioning valve to the control of gun traffic in the utility model, namely with the 3rd electric Proportion valve 205 control pneumatic proportional valve 107, control again pressure and the flow of coating pipelines by pneumatic proportional valve 107, control algolithm adopts the PID method, and a typical control procedure is:
3. the typical operation of paint finishing
Pipeline circular flow, pid control parameter, paint pump drive air pressure, stirrer-driven air pressure, Switch of spray pistol rifle air pressure, spray gun atomization air pressure, spray gun fan width of cloth air pressure etc. when 1) being inputted or being revised default gun traffic, default pass rifle by the staff in the human-computer interaction interface of host computer 301.
2) carrying out spraying prepares, control system powers on, and the staff sends instruction unpack the first electric Proportion valve 203, the second electric Proportion valve 204 at the human-computer interaction interface of host computer 301, and paint pump and agitator are opened thereupon, paint finishing is started working, and coating circulates in pipeline.
3) under not shooting state, feed pipe digital flowmeter 108 detects the circular flow in the current pipeline, and the result is transferred to controller, and controller sends to host computer 301 with present flow rate information on the one hand, is shown at human-computer interaction interface; On the one hand with this flow during with default pass rifle the pipeline circular flow compare, and give the 3rd electric Proportion valve 205 according to comparative result output control signal, the valve port opening of corresponding control pneumatic proportional valve 107 realizes the adjusting of pipeline circular flow, makes it to level off to default pipeline circular flow.
When 4) beginning to spray, the staff sends the shooting instruction at the human-computer interaction interface of host computer 301, PLC controller 302 at first is converted into analog signal with atomization air pressure value and the fan width of cloth air pressure value of appointment, and send to the 4th electric Proportion valve 206, the 5th electric Proportion valve 207, the atomizing air of spray gun and fan width of cloth air are opened, and reach preset pressure value rapidly; Then, PLC controller 302 is converted into analog signal with the shooting air pressure value of appointment again, and the air pressure that sends to the 6th electric Proportion valve 208, the six electric Proportion valves 208 outputs reaches rapidly preset value, and the spray gun needle-valve is backed down, the spray gun shooting.
5) in the spraying process, feed pipe digital flowmeter 108 gathers the feed pipe flow signal, feed back pipe digital flowmeter 110 gathers feed back pipe flow signal, and respectively the result is transferred to PLC controller 302, PLC controller 302 is asked the poor gun traffic that obtains to the two, then on the one hand gun traffic information is sent to host computer 301, shown at human-computer interaction interface; On the one hand this flow and the gun traffic of presetting are compared, and give the 3rd electric Proportion valve 205 according to comparative result output control signal, the valve port opening of corresponding control pneumatic proportional valve 107 realizes the adjusting of gun traffic, makes it to level off to default gun traffic.
When 6) needing adjust flux in the system work process, in the human-computer interaction interface of host computer 301, revise default flow by the staff, then send to PLC controller 302, PLC controller 302 is with comparing with present flow rate of being about to, and give the 3rd electric Proportion valve 205 according to comparative result output control signal, the valve port opening of corresponding control pneumatic proportional valve 107, long-range, the On-line Control of realization gun traffic; When needing to regulate air pressure, in the human-computer interaction interface of host computer 301, revise default air pressure value by the staff, then send to PLC controller 302, PLC controller 302 is converted into analog signal with the air pressure value that is about to appointment, and send to corresponding electric Proportion valve, realize the remote adjustment of air pressure.
When 7) spraying finished, host computer 301 sent and closes the rifle instruction, and PLC controller 302 at first cuts out the 6th electric Proportion valve 208, and the air pressure of the 6th electric Proportion valve 208 outputs reduces to rapidly 0, spray gun needle-valve return, and spray gun closes rifle; Then, PLC controller 302 cuts out the 4th electric Proportion valve 206, the five electric Proportion valves 207, and the atomizing air of spray gun and fan width of cloth air are also closed thereupon.
8) after spraying operation finishes, carry out the work such as emptying, cleaning, close paint pump 103 and agitator 102, the control system outage.
Claims (6)
1. a robot is comprised of fluid section, air path part, control section with two-flow meter formula digitlization paint finishing, it is characterized in that:
Coating feed pipe (001) connects from container for paint (101), connect successively paint pump (103), filter (104), voltage-stablizer (105), pressure regulator valve (106), pneumatic proportional valve (107), feed pipe digital flowmeter (108), finally be connected to the charging aperture of automatic spray gun (109), coating return duct (002) connects from the feedback outlet of automatic spray gun (109), is connected back to container for paint (101) through feed back pipe digital flowmeter (110), counterbalance valve (111);
Air hose (003) connects from source of the gas (201), behind air cleaner (202), be divided into six the tunnel, the first via is through the first electric Proportion valve (203), oil sprayer (209) is connected to agitator (102), the second the tunnel is connected to paint pump (103) and voltage-stablizer (105) through the second electric Proportion valve (204), Third Road is connected to pneumatic proportional valve (107) through the 3rd electric Proportion valve (205), the four the tunnel is connected to the atomizing air entrance of automatic spray gun (109) through the 4th electric Proportion valve (206), the five the tunnel is connected to the fan width of cloth air intake of automatic spray gun (109) through the 5th electric Proportion valve (207), and the six the tunnel is connected to the switch rifle air intake of automatic spray gun (109) through the 6th electric Proportion valve (208);
Control section comprises host computer (301) and the PLC controller (302) that contains control program, feed pipe digital flowmeter (108) links to each other by the pulse signal acquisition module of control circuit with PLC controller (302) respectively with feed back pipe digital flowmeter (110), six electric Proportion valves link to each other by the D/A module of control circuit with PLC controller (302) respectively, and PLC controller (302) links to each other with host computer (301) by control circuit.
2. robot according to claim 1 is characterized in that: host computer (301) employing industrial computer or touch-screen with two-flow meter formula digitlization paint finishing.
3. robot according to claim 1 is characterized in that: feed pipe digital flowmeter (108) and feed back pipe digital flowmeter (110) employing intrinsic safety formula digital flowmeter with two-flow meter formula digitlization paint finishing.
4. robot according to claim 1 is with two-flow meter formula digitlization paint finishing, and it is characterized in that: electric Proportion valve and PLC controller (302) all place in the explosion proof control case (005).
5. robot according to claim 1 is characterized in that: described paint pump (103) employing membrane pump, piston pump or gear pump with two-flow meter formula digitlization paint finishing.
6. robot according to claim 1 is characterized in that: described automatic spray gun (109) employing automatic air spray gun with two-flow meter formula digitlization paint finishing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220140707 CN202667047U (en) | 2012-04-05 | 2012-04-05 | Double-flowmeter digitization spraying system for robot |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220140707 CN202667047U (en) | 2012-04-05 | 2012-04-05 | Double-flowmeter digitization spraying system for robot |
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| Publication Number | Publication Date |
|---|---|
| CN202667047U true CN202667047U (en) | 2013-01-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220140707 Expired - Lifetime CN202667047U (en) | 2012-04-05 | 2012-04-05 | Double-flowmeter digitization spraying system for robot |
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| Country | Link |
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| CN (1) | CN202667047U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102632003A (en) * | 2012-04-05 | 2012-08-15 | 清华大学 | Dual-flow-meter type digital spraying system for robot |
| CN111013852A (en) * | 2019-12-23 | 2020-04-17 | 广东创智智能装备有限公司 | Non-contact fluid conveying and flow monitoring closed-loop control device |
-
2012
- 2012-04-05 CN CN 201220140707 patent/CN202667047U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102632003A (en) * | 2012-04-05 | 2012-08-15 | 清华大学 | Dual-flow-meter type digital spraying system for robot |
| CN111013852A (en) * | 2019-12-23 | 2020-04-17 | 广东创智智能装备有限公司 | Non-contact fluid conveying and flow monitoring closed-loop control device |
| CN111013852B (en) * | 2019-12-23 | 2023-11-14 | 广东创智智能装备有限公司 | Non-contact fluid conveying and flow monitoring closed-loop control device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20180209 Address after: 300300 Tianjin Huaming street Dongli Huaming Road No. 36 Building No. 2 Patentee after: Qingyan co creation robot (Tianjin) Co., Ltd. Address before: 100084 Haidian District, Beijing,,, Tsinghua University, the 100084 letter box office Patentee before: Tsinghua University |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130116 |