CN111521100A - Winding degree measuring instrument for gun barrel equi-clean rifling - Google Patents

Winding degree measuring instrument for gun barrel equi-clean rifling Download PDF

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Publication number
CN111521100A
CN111521100A CN202010352616.0A CN202010352616A CN111521100A CN 111521100 A CN111521100 A CN 111521100A CN 202010352616 A CN202010352616 A CN 202010352616A CN 111521100 A CN111521100 A CN 111521100A
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China
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rifling
probe
rotary encoder
walking wheel
driven
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CN202010352616.0A
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CN111521100B (en
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戴恒震
范鸿吉
林滨
张淞瑜
韩雨辰
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Dalian University of Technology
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Dalian University of Technology
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B5/00Measuring arrangements characterised by the use of mechanical techniques
    • G01B5/24Measuring arrangements characterised by the use of mechanical techniques for measuring angles or tapers; for testing the alignment of axes

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • A Measuring Device Byusing Mechanical Method (AREA)
  • Length Measuring Devices With Unspecified Measuring Means (AREA)

Abstract

The invention belongs to the technical field of geometric precision detection of barrel equi-alignment rifling and discloses a barrel equi-alignment rifling winding degree measuring instrument which comprises a protective shell, a mandrel, a driving motor, a driving travelling wheel, a driven travelling wheel, a driving travelling wheel carrier, a driven travelling wheel carrier, a probe, a torsion spring, a tension spring, a swing frame, an inclination angle sensor, a laser ranging head, a rotary encoder, a cable and the like. The front end of the protective shell is provided with an inclination angle sensor and a laser ranging head, and the rear end of the protective shell is led out with a power supply and communication cable. The front probe, the driven walking wheel frame, the driving walking wheel frame, the rear probe and the rotary encoder frame are arranged on the mandrel. The walking wheels are driven by the speed reducing motor to walk in the rifling grooves, the front probes and the rear probes slide along the side walls of the rifling grooves in a contact mode, and the measurement of the rifling degree of the gun barrel is realized by utilizing a combined mode of a rotary encoder, an inclination angle sensor and a laser ranging head.

Description

Winding degree measuring instrument for gun barrel equi-clean rifling
Technical Field
The invention belongs to the technical field of geometric precision detection of barrel equi-alignment rifling, and particularly relates to a barrel equi-alignment rifling winding degree measuring instrument.
Background
In modern weapons, barrel rifling is one of the key structures in artillery barrels, and the purpose of the equi-aligning rifling is to enable a projectile to rotate along the rifling when the artillery launches the projectile, so that a certain linear initial velocity and a certain rotation angular velocity are given to the projectile, and the trajectory of the projectile is stable. Whether the rotation degree of the gun reaches the standard or not can cause great influence on the quality of key operational performance indexes such as the shooting precision, trajectory stability, initial speed of the cannonball and the like of the cannonball. In the processing process of the gun barrel of the artillery, the quality of the artillery is greatly influenced by the influence of various factors such as cutter bar deformation, system flutter, workpiece material, drill bit parameters, cutting parameters, difficult chip removal and the like. Therefore, the curl is an important index for evaluating the quality of a gun barrel, and the curl deviation of the gun barrel must be closely monitored in the whole manufacturing process.
At present, researches in the field of rifling winding detection of gun barrels at home and abroad have been made with a lot of excellent achievements, but compared with other metering projects, a winding detection technology of the rifling winding is laggard, most of winding detectors applied in actual production use a template matching-based method to compare images of a CCD (charge coupled device) with a standard template so as to evaluate whether the curl is qualified, but the method cannot accurately measure the winding of the gun barrel rifling. The grating is used, but the device needs to be precisely adjusted and fixed, otherwise the straightness accuracy is greatly influenced, the measurement cannot be realized on machine due to the field limitation and the proficiency of operators, and the measurement needs to be carried out after a plurality of machining processes are finished, so that the accuracy of subsequent machining is influenced.
And the high-precision rifling winding degree detection instrument is very expensive and difficult to be widely applied.
Disclosure of Invention
According to the technical problems, the invention provides a winding degree measuring instrument for a rifling line of a gun barrel and the like.
The technical scheme of the invention is as follows:
a measuring instrument for winding degree of a neat rifling of a gun barrel and the like comprises a protective shell, a mandrel, a driving motor, a driving travelling wheel, a driven travelling wheel, a driving travelling wheel carrier, a driven travelling wheel carrier, a probe, a torsion spring, a tension spring, a swing frame, an inclination angle sensor, a laser ranging head, a rotary encoder, a cable and the like. The protective shell is of a cylindrical structure, rectangular holes are symmetrically formed in the upper surface of the protective shell to expose the probes and the travelling wheels, the protective shell is coaxially matched with the mandrel and is fixed into a whole by nuts, the front end of the protective shell is provided with the tilt angle sensor and the laser ranging head, and the rear end of the protective shell is provided with the power supply and communication cable. The front probe is fixed at the front part of the mandrel, and the driven walking wheel frame, the driving walking wheel frame, the rear probe and the rotary encoder frame are sequentially sleeved behind the front probe.
Two ends of the mandrel are sleeved with two mechanical angle probes, two groups of torsion springs are arranged in the two probes in a measuring mode and provide opposite torsion forces for the two probes, the torsion springs are used for enabling the two probes to be tightly attached to the inner wall of the rifling to be measured, and the probes are prevented from being separated from the side face of the rifling groove in the measuring process.
The driven travelling wheel frame is fixed on the mandrel, and the upper end and the lower end of the driven travelling wheel frame are provided with through holes for fixing two driven travelling wheels; the active walking wheel frame is sleeved on the mandrel and can freely rotate, a speed reduction motor is directly installed at the lower part of the active walking wheel frame, an active walking wheel is installed on an output shaft of the motor, a swinging arm is directly installed at the upper part of the active walking wheel frame, and the speed reduction motor and the active walking wheel are also installed at one end of the swinging arm.
The other end of the swinging arm is articulated with a tension spring, the other end of the tension spring is articulated in a small hole at the lower part of the active walking wheel frame, and the swinging arm drives the upper active walking wheel and the lower active walking wheel to be tightly close to the wall of the rifling, so that the walking is facilitated.
The rotary encoder is used for measuring the relative rotation angle between the front probe and the rear probe, the shell of the rotary encoder is fixed on the rotary encoder support, and the input shaft of the rotary encoder is fixed on the core shaft through the coupler.
When the measuring device is used, the barrel equi-alignment rifling winding degree measuring instrument is placed into the opening end of a barrel to be measured, the two driven wheels, the two driving wheels and the two groups of probes are all tightly pressed on the inner wall of the barrel to be measured under the action of the spring, a certain voltage is applied to the power supply cable at the moment, the speed reduction motor is started, and the two driving wheels drive the two driven wheels, so that the whole barrel equi-alignment rifling winding degree measuring instrument is pushed to move forwards along rifling in the barrel to be measured; the inclination angle sensor measures the rotation angle of the axis of the whole gun barrel.
The two groups of probes can continuously reflect the change of an included angle between the two spans in the advancing process of the measuring instrument, the two groups of probes are converted into digital signals by the rotary encoder, the inclination angle sensor measures the rotating angle of the whole measuring instrument along the axis of the gun barrel, and the laser ranging head records the advancing distance of the measuring instrument in the advancing process; the three groups of data are collected and transmitted to a data processing terminal, and finally, the output result is compared with the winding angle value of the standard rifling through calculation processing, so that whether the rifling to be measured is standard or not can be obtained.
The invention has the beneficial effects that: the invention utilizes the contact measurement of the mechanical probe to change the measurement of the winding degree from the optical scanning measurement into the mechanical measurement, and because the uncertain errors such as diffuse reflection and the like are avoided, the measurement accuracy is improved, the on-machine measurement can be realized, and the use is simple and convenient.
Drawings
FIG. 1 is an overall appearance diagram of a barrel equi-rifling winding degree measuring instrument;
FIG. 2 is an internal structure diagram of a barrel equi-rifling winding degree measuring instrument;
FIG. 3 is a schematic view of an assembly structure of the driving wheel carrier and the reduction motor;
fig. 4 is a schematic view of an encoder and encoder rack installation.
In the figure: the device comprises a laser ranging head 1, a tilt angle sensor 2, a front probe 3, a probe 4, a driven travelling wheel 5, a driven travelling wheel frame 6, a tension spring 7, a driving travelling wheel 8, a speed reducing motor 9, a mandrel 10, a screw 11, a cable 12, a rotary encoder 13, a rotary encoder bracket 14, a rear probe 15, a shell 16, a driving travelling wheel frame 17, a torsion spring 18 and a swing arm 19.
Detailed Description
For the purpose of illustrating the objects, technical solutions and features of the present invention, the technical solutions in the embodiments of the present invention will be further described below with reference to the accompanying drawings in the embodiments of the present invention.
As shown in fig. 1 and 2, a measuring instrument for winding degree of a flush rifling of a gun barrel and the like comprises a laser ranging head 1, an inclination angle sensor 2, a front probe 3, a probe 4, a driven traveling wheel 5, a driven traveling wheel carrier 6, a tension spring 7, a driving traveling wheel 8, a speed reducing motor 9, a mandrel 10, a screw 11, a cable 12, a rotary encoder 13, a rotary encoder bracket 14, a rear probe 15, a protective shell 16, a driving traveling wheel carrier 17, a torsion spring 18 and a swing arm 19;
the cylindrical protective shell 16 is coaxially matched and fixed with the mandrel 10, the front end of the protective shell 16 is provided with the tilt angle sensor 2 and the laser ranging head 1, and the rear end of the protective shell 16 is provided with the power supply and communication cable 12; the front probe 3 is sleeved on the front part of the mandrel 10 and is fixed, and a torsion spring 18, a driven walking wheel frame 6, a driving walking wheel frame 17, a torsion spring 18, a rear probe 15 and a rotary encoder bracket 14 are sequentially sleeved on the mandrel 10 behind the front probe 3.
The front probe 3 and the rear probe 15 are of square rod structures with a middle round hole, the two ends of the square rod are respectively provided with a micro spherical wear-resistant probe 4, the distance between the probes 4 at the two ends enables the probes to be just embedded into a barrel bore line slot, and the probes cannot be clamped when being close to the bottom of the slot; the two torsion springs 18 are used for providing necessary torsion force by virtue of the driven travelling wheel frame 6 and the driven travelling wheel frame 17, so that the front probe 3 and the rear probe 15 are tightly attached to the side wall of the rifling to be measured, and are prevented from loosening from the side surface of the rifling during measurement.
The driven travelling wheel carrier 6 is of a plate-shaped structure with a middle sleeve, the upper surface and the lower surface of the plate have a certain angle so as to adapt to the rifling angle winding of the gun barrel, the upper surface and the lower surface of the plate are respectively provided with a driven travelling wheel 5, and the distance between the axes of the two driven travelling wheels 5 enables the driven travelling wheels 5 to be just embedded into the rifling groove of the gun barrel to walk easily.
As shown in fig. 3, the active traveling wheel carrier 17 also has a plate-shaped structure with a middle sleeve, and is sleeved on the mandrel 10 to be freely rotatable, the speed reduction motor 9 is directly installed at the lower part of the active traveling wheel carrier 17 through a screw 11, the active traveling wheel 8 is installed on the output shaft of the speed reduction motor 9, the upper part of the active traveling wheel carrier 17 is hinged with a swing arm 19, and the speed reduction motor 9 and the active traveling wheel 8 are also installed at one end of the swing arm 19.
The other end of the swing arm 19 is connected with a tension spring 7 in a hanging mode, the other end of the tension spring 7 is connected in a small hole in the lower portion of the active walking wheel frame 17 in a hanging mode, under the tensile force effect of the tension spring 7, the swing arm drives the outer cylindrical surfaces of the upper active walking wheel 8 and the lower active walking wheel 8 to be close to the bottom of the rifling groove, and sufficient friction force is formed to facilitate walking.
As shown in fig. 4, the rotary encoder 13 is used to measure the relative rotation angle of the span between the front probe 3 and the rear probe 15, the housing of the rotary encoder 13 is fixed on the rotary encoder bracket 14, and the input shaft of the rotary encoder 13 is fixed on the mandrel 10 through a coupling.
When the rifling of the gun barrel is required to be measured, the gun barrel equi-alignment rifling winding degree measuring instrument is placed into the opening end of the gun barrel to be measured, due to the action of the spring, the two driven wheels 5, the two driving wheels 8 and the two groups of probe probes 4 are all tightly pressed on the inner wall of the gun barrel to be measured, after the power supply is switched on, the speed reducing motor 9 is started, the two driving wheels 8 are driven, the two driven wheels 5 follow up, and therefore the whole gun barrel equi-alignment rifling winding degree measuring instrument is pushed to move forwards along the rifling in the gun barrel to be measured; the inclination angle sensor 2 measures the rotation angle of the whole instrument along the axis of the gun barrel, the relative swing of the front probe 3 and the rear probe 15 in the advancing process of the measuring instrument can continuously reflect the change of the included angle between the front probe and the rear probe, the front probe and the rear probe are converted into digital signals by the rotary encoder 13, and the laser ranging head 1 records the advancing distance of the instrument in the advancing process; the three groups of data are collected and transmitted to an external data processing terminal, and finally, the output result is compared with the winding angle value of the standard rifling after calculation processing, so that whether the rifling to be measured is standard or not can be evaluated.

Claims (1)

1. The instrument for measuring the winding degree of the equi-aligning rifling of the gun barrel is characterized by comprising a laser ranging head (1), an inclination angle sensor (2), a front probe (3), a probe (4), a driven travelling wheel (5), a driven travelling wheel carrier (6), a tension spring (7), a driving travelling wheel (8), a speed reducing motor (9), a mandrel (10), a screw (11), a cable (12), a rotary encoder (13), a rotary encoder bracket (14), a rear probe (15), a protective shell (16), a driving travelling wheel carrier (17), a torsion spring (18) and a swing arm (19);
the cylindrical protective shell (16) is coaxially matched and fixed with the mandrel (10), the front end of the protective shell (16) is provided with the tilt angle sensor (2) and the laser ranging head (1), and the rear end of the protective shell (16) is provided with a power supply and communication cable (12); the front probe (3) is sleeved on the front part of the mandrel (10) and is fixed, and a torsion spring (18), a driven walking wheel frame (6), a driving walking wheel frame (17), a torsion spring (18), a rear probe (15) and a rotary encoder bracket (14) are sequentially sleeved on the mandrel (10) behind the front probe (3);
the front probe (3) and the rear probe (15) are of square rod structures with a middle round hole, the two ends of each square rod are respectively provided with a micro spherical wear-resistant probe (4), the distance between the probes (4) at the two ends enables the probes to be just embedded into a line slot of a bore of a gun barrel, and the probes are close to the bottom of the slot and cannot be clamped; the two torsion springs (18) are used for providing necessary torsion force by virtue of the driven walking wheel frame (6) and the main walking wheel frame 17, so that the front probe (3) and the rear probe (15) are tightly attached to the side wall of the rifling to be measured, and the side surface of the rifling is prevented from loosening during measurement;
the driven travelling wheel carrier (6) is of a plate-shaped structure with a middle sleeve, the upper surface and the lower surface of the plate have a certain angle to adapt to the rifling winding angle of the gun barrel, the upper surface and the lower surface of the plate are respectively provided with one driven travelling wheel (5), and the distance between the axes of the two driven travelling wheels (5) enables the driven travelling wheels (5) to be just embedded into the rifling grooves of the gun barrel to easily travel;
the active walking wheel carrier (17) is also provided with a plate-shaped structure with a middle sleeve, is sleeved on the mandrel (10) and can freely rotate, the lower part of the active walking wheel carrier (17) is directly provided with a speed reducing motor (9) through a screw (11), an output shaft of the speed reducing motor (9) is provided with an active walking wheel (8), the upper part of the active walking wheel carrier (17) is hinged with a swinging arm (19), and one end of the swinging arm (19) is also provided with the speed reducing motor (9) and the active walking wheel (8);
the other end of the swing arm (19) is articulated with a tension spring (7), the other end of the tension spring (7) is articulated in a small hole at the lower part of the active walking wheel carrier (17), and the swing arm drives the outer cylindrical surfaces of the upper active walking wheel (8) and the lower active walking wheel (8) to lean against the bottom of the rifling groove under the tension action of the tension spring (7) to form enough friction force for walking;
the rotary encoder (13) is used for measuring the relative rotation angle of the span between the front probe (3) and the rear probe (15), the shell of the rotary encoder (13) is fixed on the rotary encoder support (14), and the input shaft of the rotary encoder (13) is fixed on the mandrel (10) through a coupling.
CN202010352616.0A 2020-04-29 2020-04-29 Winding degree measuring instrument for gun barrel equi-clean rifling Active CN111521100B (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112414210A (en) * 2020-11-19 2021-02-26 齐鲁工业大学 Gun barrel bore line detection robot and detection method
CN114061530A (en) * 2021-11-17 2022-02-18 大连理工大学 Deep hole straightness measuring device and method

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112414210A (en) * 2020-11-19 2021-02-26 齐鲁工业大学 Gun barrel bore line detection robot and detection method
CN112414210B (en) * 2020-11-19 2022-08-16 齐鲁工业大学 Gun barrel bore line detection robot and detection method
CN114061530A (en) * 2021-11-17 2022-02-18 大连理工大学 Deep hole straightness measuring device and method

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