CN103217294A - Zero point judgment and control mechanism for valve stroke of internal combustion engine air flue current stabilization test bed - Google Patents
Zero point judgment and control mechanism for valve stroke of internal combustion engine air flue current stabilization test bed Download PDFInfo
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- CN103217294A CN103217294A CN2013100890386A CN201310089038A CN103217294A CN 103217294 A CN103217294 A CN 103217294A CN 2013100890386 A CN2013100890386 A CN 2013100890386A CN 201310089038 A CN201310089038 A CN 201310089038A CN 103217294 A CN103217294 A CN 103217294A
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Abstract
The invention discloses a zero point judgment and control mechanism for a valve stroke of an internal combustion engine air flue current stabilization test bed. According to the technical scheme, the zero point judgment and control mechanism is formed by combination of two vertical plates, extension shafts of two transverse linear stepping motors, and a transverse arm, wherein a gantry type frame is formed above a work table top, and a hydraulic cylinder shaft enables the frame to shift up and down. Steering motors are fixed on connecting blocks of the extension shafts of the transverse linear stepping motors, cylindrical gear plates are welded with transverse arm short shafts, and the steering motors drive the gear plates and gears to enable the transverse arm to rotate. Two longitudinal linear stepping motors are fixed on the transverse arm, a sensor upper sleeve and a sensor lower sleeve are connected with the lower ends of the extension shafts of the motors, a guiding sliding sleeve, a lower ejector rod and a pressure sensor are arranged in each sleeve, each pressure sensor is contacted with the top face of each guiding sliding sleeve to output signals to a computer to detect through displacement of each lower ejector rod. The mechanism not only can eliminate manual installation and disassembling operation of a cylinder cover pressing plate, the valve stroke is high in control precision, and zero point judgment can be carried out on cylinder covers of different kinds of valve spring pre-tightening force.
Description
Technical field
The invention belongs to engine performance parameter detecting technology, be specifically related to a kind of experiment detection device that engine valve position or lift displacement are measured and controlled.
Background technology
Well-known internal combustion engine is the maximum industry of consumption of petroleum, accounts for 60% of China's oil total flow; The discharging of motor vehicle has simultaneously more aggravated the deterioration of urban environment, and is therefore significant to the innovation of internal combustion engine energy-conserving and emission-cutting technology.The air flue of internal combustion engine is as " throat ", the good and bad appreciable impact oil consumption and the emission level of its flowing property.For making internal combustion engine reach good power, economy and emission performance, precondition is that air flue must be able to be realized sufficiently high coefficient of flow and suitable swirl ratio, roll stream and compare etc.Because dynamic evaluation air passage of internal combustion engine Effect on Performance factor is many and be difficult to control, therefore utilizing the steady flow testbed air flue performance is evaluated and tested of air passage of internal combustion engine is extensively to adopt and efficient ways.When carrying out the test of air flue current stabilization, what at first need to carry out valve aligns and compresses debugging, need set different valve strokes in continuous or interrupted mode subsequently, the accuracy of the stability of valve hold-down mechanism and valve stroke control will have influence on the test result of parameter.
In present air passage of internal combustion engine was steady flow testbed, valve compressed and the lift control gear mainly contains three kinds of forms: (1) adopts pad to regulate valve stroke, regulates by the pad of different-thickness.This mode has been destroyed the integrality of air valve structure, and long-term the use because of wearing and tearing cause valve stroke of pad judged and the control accuracy reduction zero point; (2) mode that adopts pointer dial gauge and pressing plate is installed.Though this kind mode has remedied the defective of first method, valve stroke judges that still tested person personnel's subjectivity influence is bigger zero point, and the test error change obviously before and after causing; (3) adopt the turbine and worm multiple-degree-of-freedom mechanism, transmission is accurately controlled valve stroke by turbine and worm.This kind mode still needs by pressing plate fixation measuring device, and judges the experience that still is limited by the tester zero point, and precision is low and be difficult to control.The operating process of aforesaid way is except that comparatively loaded down with trivial details, when difference cylinder is tested, need the tester manually to change pressing plate, this can cause test macro can not adapt to the beat of the online detection of engine cylinder cover, has limited the raising of steady flow testbed of air passage test job efficient.
Along with raising to the performance requirement of engine cylinder cover entering and exhaust channel, requirement detects one by one to each cylinder cap air flue on production line, and this develops a kind of job stability height with regard to pressing for, can fast automaticly carry out the device that valve aligned and compressed, accurately controlled valve stroke adapts to the online detection beat of steady flow testbed of air passage.Proposition of the present invention can be satisfied the requirement to the online high Precision Detection of engine cylinder cover.
Summary of the invention
The objective of the invention is, when carrying out the test of air passage of internal combustion engine current stabilization, provide a kind of valve location of can carrying out automatically to compress, accurately judge valve stroke null position and control gear.
Below with reference to accompanying drawing technical pattern of the present invention and principle are described.The steady flow testbed valve stroke of air passage of internal combustion engine is judged and control gear, comprise work top zero point, riser, horizontal linear stepping motor, linear bearing, the prolongation axle of horizontal linear stepping motor, contiguous block, transverse arm, upper junction plate, gusset, hydraulic cylinder, guide pillar, lower connecting plate, steer motor, spur gear wheel, the cylindrical gear dish, vertical linear stepping motor, the prolongation axle of vertical linear stepping motor, overlap on the sensor, sensor is trapped, guide sleeve, holddown spring, pressure transducer, retracing spring, lower push rod, depression bar, cylinder cap, support set, pressing plate and terminal pad etc.Control gear is by the compressing structure frame assembly and judge that the assembly two large divisions forms zero point, the compressing structure frame assembly by: hydraulic cylinder, straight line guide pillar, two web joints, gantry type frame, two horizontal linear stepping motors, contiguous block, steer motor, spur gear wheel, cylindrical gear dish and two vertical linear stepping motor parts are formed up and down; Valve stroke judge zero point assembly by: sensor upper bush, sensor lower sleeve, guide sleeve, holddown spring, pressure transducer, retracing spring and lower push rod parts are formed.
Technical scheme of the present invention is: work top is provided with two risers, the outer end of left side vertical plate is provided with two horizontal linear stepping motors, the position that two horizontal linear stepping motors of right side riser and left side are relative is provided with linear bearing, and the prolongation axle of horizontal linear stepping motor passes the left side vertical plate edge and crouches in the linear bearing of right side riser.The prolongation axle of horizontal stepper motor is welded with contiguous block, and the two ends of transverse arm are welded with minor axis, and the transverse arm minor axis prolongs axle by contiguous block with two horizontal linear stepping motors and is connected.Prolongation axle and transverse arm by two risers, two horizontal linear stepping motors are combined, and constitute a gantry type frame above work top.The outside of two risers all is welded with upper junction plate, and riser and upper junction plate are welded as a whole by gusset.The axle of hydraulic cylinder and the guide pillar of both sides passes work top and lower connecting plate is fixed, hydraulic cylinder holds up upper and lower web joint can make the gantry type frame upper and lower displacement.Steer motor is fixed on the contiguous block, and steer motor is connected with spur gear wheel, the intermediate shaft welding of cylindrical gear dish and transverse arm, and cylindrical gear dish and spur gear wheel engagement, steer motor drives spur gear wheel rotates transverse arm.Two vertical linear stepping motors are fixed on the transverse arm, and two horizontal linear stepping motor driven in synchronism prolongation axle separately produces axial displacement, drives transverse arm thus and produces transverse movement.Vertically the prolongation axle lower end of linear stepping motor is connected on the sensor by screw thread and overlaps, and sensor is trapped fixing by cover on screw and the sensor.In trapping, sensor is provided with guide sleeve, guide sleeve penetrates in the holddown spring, and pressure transducer is nested with retracing spring, retracing spring on the sensor cover and guide sleeve between, guide sleeve is connected with lower push rod by screw thread, and lower push rod is connected by screw with depression bar.Cylinder cap to be tested is placed at the center of work top, and the cylinder cap support set is fixed by pressing plate and terminal pad, and cylinder cap is fixed in cylinder cap support set upper surface.
The compressing structure frame assembly possesses four degree of freedom: the displacement of the lines that the displacement of the lines of the prolongation axle of gantry type frame upper and lower displacement, horizontal linear stepping motor, transverse arm corner displacement and vertical linear stepping motor prolong axle.Can position and compress operation to any cylinder head valve thus.
Beneficial effect of the present invention is: (1) can be evaluated and tested the air flue performance of multicylinder engine, and it is little that pick-up unit has a volume, and compact conformation is easy for installation, characteristics such as automaticity height; (2) this device cooperates with the cylinder cap auto feed system, can realize the unmanned full-automatic online detection of interfering, and reduces the influence of human factor to test result, improves measuring accuracy; (3) the pressure transducer range ability is big, the null position decision errors can be controlled at simultaneously ± 0.05mm in, can carry out zero point to the cylinder cap of various different air valve initial tension of spring and judge, applied widely; (4) can save the artificial installation and the dismantlement work of cylinder cap pressing plate.
Description of drawings
Accompanying drawing 1 is technical pattern of the present invention and schematic diagram.
Accompanying drawing 2 is the local enlarged diagram of transverse arm corner displacement governor motion.
Accompanying drawing 3 is judged the assembly diagrammatic cross-section for the valve stroke null position.
Embodiment
Below in conjunction with accompanying drawing and by embodiment structure of the present invention and principle are described further.
The steady flow testbed valve stroke of air passage of internal combustion engine is judged and control gear zero point, its parts are formed and technical pattern is: work top 1 is provided with two risers 2, the outer end of left side vertical plate is provided with two horizontal linear stepping motors 3, the position that two horizontal linear stepping motors of right side riser and left side are relative is provided with linear bearing 4, and the prolongation axle 5 of horizontal linear stepping motor passes the left side vertical plate edge and crouches in the linear bearing of right side riser.The prolongation axle of horizontal stepper motor is welded with contiguous block 6, and the two ends of transverse arm 7 are welded with minor axis, and the transverse arm minor axis prolongs axle by contiguous block with two horizontal linear stepping motors and is connected.Prolongation axle and transverse arm by two risers, two horizontal linear stepping motors are combined, and constitute a gantry type frame above work top.The outside of two risers all is welded with upper junction plate 8, and riser and upper junction plate are welded as a whole by gusset 9 again.The axle of hydraulic cylinder 10 and the guide pillar 11 of both sides pass work top and lower connecting plate 12 is fixing, and hydraulic cylinder holds up upper and lower web joint can make gantry type frame upper and lower displacement (as Fig. 1).
Vertically prolongation axle 17 lower ends of linear stepping motor are connected to by screw thread and overlap 18 on the sensor, and sensor is trapped and 19 fixed by cover on screw and the sensor.Be provided with guide sleeve 20 in sensor is trapped, guide sleeve penetrates in the holddown spring 21, and pressure transducer 22 is nested with retracing spring 23, retracing spring on the sensor cover and guide sleeve between.Guide sleeve is connected with lower push rod 24 by screw thread, and lower push rod is connected (as Fig. 3) with depression bar 25 by screw.
Control gear is by the compressing structure frame assembly and judge that the assembly two large divisions forms zero point, the compressing structure frame assembly by: hydraulic cylinder 10, straight line guide pillar 11, two web joints, gantry type frame, two horizontal linear stepping motors 3, contiguous block 6, steer motor 13, spur gear wheel 14, cylindrical gear dish 15 and two vertical linear stepping motor 16 parts are formed up and down.When carrying out the test of engine air flue current stabilization, the pretightning force that need overcome valve spring just can be opened head valve, and the compressing structure frame assembly of control gear is exactly to design for this reason.
Valve stroke judge zero point assembly by: sensor upper bush 18, sensor lower sleeve 19, guide sleeve 20, holddown spring 21, pressure transducer 22, retracing spring 23 and lower push rod 24 parts are formed, and judge the assembly motion zero point by two vertical linear stepping motor driven in synchronism.
During test cylinder head is fixed in above the cylinder cap support set, debugging is proofreaied and correct and compressed to valve to be measured.The corresponding three dimensional space coordinate in valve top is input to computing machine, and computing machine will drive hydraulic cylinder and each motor moves in each degree of freedom to realize that vertical linear stepping motor prolongs axle and aligns with valve position to be measured.
Vertically linear stepping motor drives and judges that assembly moves downward along the valve stem axis direction zero point.Make lower push rod can vertically be pressed into and open valve, embodiment head valve pretightning force is 40kg.Pressure threshold value in the computer-controlled program is set at 30kg, and computing machine will drive vertical linear stepping motor and prolong axially motion down, thereby lower push rod is contacted with valve.Along with lower push rod compresses valve gradually, the gap between guide sleeve and the pressure transducer constantly diminishes, until the complete compaction pressure sensor of guide sleeve.When the pressure signal value that records when pressure transducer was increased to 30kg, computing machine position this moment and drove vertical linear stepping motor and begins numeration and measure as the valve stroke null position.
After whole test process finished, vertically linear stepping motor prolonged axle and drives valve stroke and judge that assembly does upwards drawback movement zero point.After valve was closed fully, the gap between guide sleeve tube and the pressure transducer returned to original state, and this process is promptly finished a complete test loop.
Claims (4)
1. the steady flow testbed valve stroke of air passage of internal combustion engine is judged and control gear zero point, comprise work top, riser, horizontal linear stepping motor, linear bearing, the prolongation axle of horizontal linear stepping motor, contiguous block, transverse arm, upper junction plate, gusset, hydraulic cylinder, guide pillar, lower connecting plate, steer motor, spur gear wheel, the cylindrical gear dish, vertical linear stepping motor, the prolongation axle of vertical linear stepping motor, overlap on the sensor, sensor is trapped, guide sleeve, holddown spring, pressure transducer, retracing spring, lower push rod, depression bar, cylinder cap, support set, pressing plate and terminal pad, it is characterized in that: work top (1) is provided with two risers (2), the outer end of left side vertical plate is provided with two horizontal linear stepping motors (3), the position that two horizontal linear stepping motors of right side riser and left side are relative is provided with linear bearing (4), the prolongation axle (5) of horizontal linear stepping motor passes the left side vertical plate edge and crouches in the linear bearing of right side riser, the prolongation axle of horizontal stepper motor is welded with contiguous block (6), the two ends of transverse arm (7) are welded with minor axis, the transverse arm minor axis prolongs axle by contiguous block with two horizontal linear stepping motors and is connected, by two risers, the prolongation axle and the transverse arm of two horizontal linear stepping motors are combined, above work top, constitute a gantry type frame, the outside of two risers all is welded with upper junction plate (8), riser and upper junction plate are welded as a whole by gusset (9) again, the axle of hydraulic cylinder (10) and the guide pillar (11) of both sides pass work top and lower connecting plate (12) is fixed, hydraulic cylinder holds up down, upper junction plate can make the gantry type frame upper and lower displacement, steer motor (13) is fixed on the contiguous block, steer motor is connected with spur gear wheel (14), cylindrical gear dish (15) welds with the minor axis of transverse arm one side, cylindrical gear dish and spur gear wheel engagement, steer motor drives spur gear wheel rotates transverse arm, two vertical linear stepping motors (16) are fixed on the transverse arm, two horizontal linear stepping motor driven in synchronism prolongation axle separately produces axial displacement, drive transverse arm thus and produce transverse movement, vertically prolongation axle (17) lower end of linear stepping motor is connected to cover (18) on the sensor by screw thread, sensor trap (19) fixing by cover on screw and the sensor, in trapping, sensor is provided with guide sleeve (20), guide sleeve penetrates in the holddown spring (21), pressure transducer (22) is nested with retracing spring (23), retracing spring on the sensor cover and guide sleeve between, guide sleeve is connected with lower push rod (24) by screw thread, lower push rod is connected by screw with depression bar (25), cylinder cap (26) to be tested is placed at the center of work top, cylinder cap support set (27) is fixing by pressing plate (28) and terminal pad (29), and cylinder cap is fixed in cylinder cap support set upper surface.
2. judge and control gear zero point according to the steady flow testbed valve stroke of the described air passage of internal combustion engine of claim 1, it is characterized in that described control gear by the compressing structure frame assembly with judge that the assembly two large divisions forms zero point, the compressing structure frame assembly is by described: hydraulic cylinder (10), straight line guide pillar (11), two web joints, gantry type frame, two horizontal linear stepping motors (3), contiguous block (6), steer motor (13), spur gear wheel (14), cylindrical gear dish (15) and two vertical linear stepping motors (16) parts are formed up and down; Valve stroke judges that assembly is by described zero point: sensor upper bush (18), sensor lower sleeve (19), guide sleeve (20), holddown spring (21), pressure transducer (22), retracing spring (23) and lower push rod (24) parts are formed, and judge that assembly moves zero point by two vertical linear stepping motor driven in synchronism.
3. judge and control gear zero point according to the steady flow testbed valve stroke of the described air passage of internal combustion engine of claim 1, it is characterized in that described hydraulic cylinder (10) is positioned at below the work top (1), the both sides of hydraulic cylinder are provided with the guide pillar seat, and described guide pillar (11) is fixed on the guide pillar seat.
4. judge and control gear zero point according to the steady flow testbed valve stroke of the described air passage of internal combustion engine of claim 1, it is characterized in that described transverse arm (7) is a tower structure; Described pressure transducer (22) is a loop configuration.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201310089038.6A CN103217294B (en) | 2013-03-20 | 2013-03-20 | Zero point judgment and control mechanism for valve stroke of internal combustion engine air flue current stabilization test bed |
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| CN201310089038.6A CN103217294B (en) | 2013-03-20 | 2013-03-20 | Zero point judgment and control mechanism for valve stroke of internal combustion engine air flue current stabilization test bed |
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| CN103217294B CN103217294B (en) | 2015-06-03 |
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| CN104848824A (en) * | 2014-12-17 | 2015-08-19 | 北汽福田汽车股份有限公司 | Measurement device and method for valve swing gap |
| CN111811448A (en) * | 2020-07-27 | 2020-10-23 | 延锋伟世通汽车电子有限公司 | Motor mechanical zero-position double-hole testing device and method |
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| CN111811448B (en) * | 2020-07-27 | 2021-10-22 | 延锋伟世通汽车电子有限公司 | Motor mechanical zero-position double-hole testing device and method |
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| CN103217294B (en) | 2015-06-03 |
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