CN102445137A - Device for measuring radius of spherical crown and measuring method thereof - Google Patents

Device for measuring radius of spherical crown and measuring method thereof Download PDF

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Publication number
CN102445137A
CN102445137A CN2011102806964A CN201110280696A CN102445137A CN 102445137 A CN102445137 A CN 102445137A CN 2011102806964 A CN2011102806964 A CN 2011102806964A CN 201110280696 A CN201110280696 A CN 201110280696A CN 102445137 A CN102445137 A CN 102445137A
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measuring staff
interior
spherical crown
measuring
staff
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杨明
张厚晚
刘立仁
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Feny Co Ltd
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Feny Co Ltd
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Abstract

The invention discloses a device for measuring radius of a spherical crown and a measuring method thereof. The device comprises an outer measuring rod (1), an inner measuring rod (2), a dial indicator (4) and a standard block (3), wherein the inner measuring rod (2) is arranged inside the outer measuring rod (1), and contacts with the surface of the measured spherical crown by a measuring rod outer circle or an inner hole; and the standard block (4) is added by the dial indicator (4) to read out the end surface fall of two measuring rods; and then the radius of the measured workpiece is calculated. The device has a very simple structure, convenience in use and high measuring precision.

Description

A kind of device and measuring method thereof of measuring the spherical crown radius
Technical field
The present invention relates to a kind of device of measuring the spherical crown radius, also relate to the easy to use of a kind of this measurement mechanism, the spherical crown radius measurement method that measuring accuracy is high.
Background technology
In commercial production and product maintenance process, often to measure the spherical radius of some sphere products.For example concrete pump tilt cylinder ball-and-socket, oil cylinder bulb, internal combustion engine oil nozzle oil pump roller pin.Because spherical crown is less than hemisphere, the pairing central angle of arbitrary circular arc is gone up less than 180 ° in its surface, and is difficult with the radius ratio of conventional gage measuring spherical crown.The circular arc slide calliper rule that existing market is sold mainly are applicable to measures cylindrical arc radius, and the someone changes a social system vernier caliper and is used to measure radius, and its method is not suitable for the radius of measuring spherical crown.The sphere curvature radius measuring instrument of China's utility model patent instructions 86201617 and Chinese utility model patent instructions 200620017626.4 announcements, complex operation, complex structure, its method of making difficulty are not suitable for the radius of measuring spherical crown yet.The existing method of measuring the spherical crown radius mainly is: 1. the common mechanical manufacturer often adopts " radius gauge " to detect the radius of spherical crown.This method is simple, but can only the guestimate radius, and measuring error more than 0.5mm, is difficult to satisfy the needs of high quality of production and scientific research and testing usually.2. adopt coordinate measurment instrument, this method measuring accuracy is high, but inconvenient operation, investment are big.
Summary of the invention
First technical matters to be solved by this invention provides a kind of simple in structure, easy to use, the device of the measurement spherical crown radius that measuring accuracy is high.
Second technical matters to be solved by this invention provides a kind of easy to use, the measuring method of the spherical crown radius that measuring accuracy is high.
In order to solve above-mentioned first technical matters; The device of measurement spherical crown radius provided by the invention; Coaxial package has interior measuring staff in the outer measuring staff; Measuring staff can be made the plunger type rectilinear motion in described in the measuring staff described outside, and the measuring point that the cylindrical of the cylindrical of described outer measuring staff and endoporus and described interior measuring staff contacts with spherical crown surface is a line style, also comprises a clock gauge that is used to measure the end face drop of described outer measuring staff (1) and described interior measuring staff.
The tolerance clearance of the internal diameter of the external diameter of measuring staff and described outer measuring staff is 0.005-0.01mm in described.
The end face of the end face of measuring staff and described outer measuring staff realizes that through synchronous processing length difference is a definite value zero in described, and promptly described outer measuring staff is consistent with the length of described interior measuring staff.
Also comprise at least one calibrated bolck, described calibrated bolck is used to fill the end face drop of described outer measuring staff and described interior measuring staff.
Described outer measuring staff and described interior measuring staff select for use tool steel T7A to make, and guarantee that through bakingout process hardness reaches 53-58HRC.
In order to solve second technical matters; The measuring method of spherical crown radius provided by the invention, the device of use has interior measuring staff by coaxial package in the outer measuring staff, and described interior measuring staff can be made the plunger type rectilinear motion in the measuring staff outside described; And the tolerance clearance of the internal diameter of the external diameter of measuring staff and described outer measuring staff is 0.005-0.01mm in described; Also comprise one be used to measure described outer measuring staff and described in the clock gauge of end face drop of measuring staff form, be in contact with one another through measuring staff cylindrical or endoporus and tested spherical crown surface, interior measuring staff and outer measuring staff are different because of external diameter; Different in the spherical crown surface contact site; Read the end face drop of outer measuring staff and interior measuring staff through clock gauge, calculate the measured workpiece radius
(1), measure interior spherical crown radius: the cylindrical of outer measuring staff contacts with the cylindrical of interior measuring staff while and tested spherical crown surface and forms two pitch circles in the spherical crown; The diameter of the pitch circle that outer measuring staff is corresponding is the diameter a of outer measuring staff; The diameter of the pitch circle that interior measuring staff is corresponding is the diameter b of interior measuring staff; Then two pitch circle distance h are the end face drop of promptly interior measuring staff of definite value and outer measuring staff; The end face drop that clock gauge is directly read interior measuring staff (2) and outer measuring staff (1) is two pitch circle distance h, and the computing formula that interior spherical crown radius is definite value r is:
Figure BDA0000092772310000021
(2), measure outer spherical crown radius: the interior circle of outer measuring staff and the end face of interior measuring staff contact with tested spherical crown surface simultaneously; The interior circle of outer measuring staff forms a pitch circle on the spherical crown surface; The diameter of pitch circle i.e. the internal diameter a of outer measuring staff; The spherical crown peak is in plane, interior measuring staff end face place; The spherical crown peak to plane, pitch circle place for definite value h promptly in measuring staff with outside the end face drop of measuring staff; The end face drop of measuring staff and outer measuring staff in clock gauge is directly read, the computing formula that outer spherical crown radius is definite value r is:
Figure BDA0000092772310000022
According to the end face drop of measuring staff in described and outer measuring staff in described measuring staff and outside interpolation corresponding standard piece between the measuring staff.
Adopt the device and the measuring method thereof of the measurement spherical crown radius of technique scheme, interior measuring staff is contained in the outer measuring staff endoporus, and the external diameter of interior measuring staff is 0.005-0.01mm with the internal diameter tolerance clearance of outer measuring staff.Measuring staff is made the plunger type rectilinear motion in the measuring staff outside in guaranteeing.The length difference of outer measuring staff and interior measuring staff should guarantee to be definite value, and interior measuring staff is packed in the outer measuring staff, and its end face synchronous processing is realized that length difference is a definite value zero, and promptly two measuring staff length are consistent.Because the spherical crown surface contacts with the cylinder end face and is basic circle, therefore, must guarantee that cylinder end face contact site is a line style, does not promptly have chamfering, non-trimming, burr etc.According to tested spherical crown diameter, select inside and outside measuring staff relative dimensions parameter, under the situation of actual measurement conditions permit, select the bigger measuring staff of diameter as far as possible, help improving measuring accuracy.The selection of calibrated bolck size equates that in the drop value that tested spherical crown surface forms permissible variation can not exceed the measurement range of clock gauge with inside and outside measuring staff.
Clock gauge is fixed on the special-purpose dial framework.
The invention has the advantages that:
1, simple in structure, include only inside and outside measuring staff and calibrated bolck, clock gauge (band dial framework) is a standard component.
2, easy to make, inside and outside measuring staff and calibrated bolck, profile is simple, and size is single, and technology is easy to guarantee its machining precision.
3, operation is simple and easy, only needs measuring staff is positioned over tested spherical crown surface, and the calibrated bolck of packing into just can be read its measured value through clock gauge.
4, precision is higher, and through the measured value of clock gauge, calculating spherical crown radius precision is 0.001mm.
Description of drawings
Fig. 1 is the cross-sectional schematic of facing of this measuring method (interior spherical crown);
Fig. 2 is the cross-sectional schematic of facing of this measuring method (outer spherical crown);
Fig. 3 is the measuring principle figure of this measuring method (interior spherical crown).
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described further.
Referring to Fig. 1, coaxial package has interior measuring staff 2 in the outer measuring staff 1, and interior measuring staff 2 is made the plunger type rectilinear motion in the measuring staff 1 outside; And the external diameter of interior measuring staff 2 is 0.005-0.01mm with the tolerance clearance of the internal diameter of outer measuring staff 1; The measuring point that the cylindrical of the cylindrical of outer measuring staff 1 and endoporus and interior measuring staff 2 contacts with spherical crown surface is a line style, does not promptly have chamfering, non-trimming, burr etc., also comprises a clock gauge 4 that is used to measure the end face drop of outer measuring staff 1 and interior measuring staff 2; The end face of interior measuring staff 2 realizes that through synchronous processing length difference is a definite value zero with the end face of outer measuring staff 1; Promptly outer measuring staff 1 is consistent with the length of interior measuring staff 2, also comprises a calibrated bolck 3, and calibrated bolck 3 is used to fill the end face drop of outer measuring staff 1 and interior measuring staff 2; Outer measuring staff 1 selects for use tool steel T7A to make with interior measuring staff 2, guarantees that through bakingout process hardness reaches 53-58HRC.
Referring to Fig. 1; Spherical crown radius in measuring: the spherical crown surface of measured workpiece is placed on the position that measuring staff is convenient to measure, outer measuring staff 1 is stood in the spherical crown with interior measuring staff 2, the cylinder end face of outer measuring staff 1 and interior measuring staff 2 fully contacts with the spherical crown surface (can not apply excessive external force; In order to avoid defective work piece and measurer contact site); The cylindrical of the cylindrical of outer measuring staff 1 and interior measuring staff 2 contacts with tested spherical crown surface simultaneously and forms two pitch circles in the spherical crown, and the diameter of the pitch circle of outer measuring staff 1 correspondence is the diameter a of outer measuring staff 1, and the diameter of the pitch circle of interior measuring staff 2 correspondences is the diameter b of interior measuring staff 2; End face drop according to outer measuring staff 1 and interior measuring staff 2 is selected corresponding standard piece 3; The endface position of measuring staff 2 in calibrated bolck 3 is put in, clock gauge 4 are packed in the dial framework, are placed on the marble platform; The gauge outfit of clock gauge 4 contacts with calibrated bolck 3 end faces; Press table to zero-bit, move horizontally dial framework, the gauge outfit of clock gauge 4 contacts with the end face of outer measuring staff 1; Measuring staff 2 was two pitch circle distance h with the end face drop of outer measuring staff 1 in clock gauge 4 was directly read, and the computing formula that interior spherical crown radius is definite value r is:
Figure BDA0000092772310000041
Referring to Fig. 2, measure outer spherical crown radius: the spherical crown surface of measured workpiece is placed on the position that measuring staff is convenient to measure, inside and outside measuring staff is stood in the spherical crown; The cylinder end face fully contacts (can not apply excessive external force, in order to avoid defective work piece and measurer contact site) with the spherical crown surface, and the interior circle of outer measuring staff 1 contacts with tested spherical crown surface with the end face of interior measuring staff 2 simultaneously; The interior circle of outer measuring staff 1 forms a pitch circle on the spherical crown surface; The diameter of pitch circle i.e. the internal diameter a of outer measuring staff 1, the spherical crown peak in plane, interior measuring staff 2 end faces place, the spherical crown peak to plane, pitch circle place for the promptly interior measuring staff 2 of definite value h and outside the end face drop of measuring staff 1; End face drop according to outer measuring staff 1 and interior measuring staff 2 is selected corresponding standard piece 3; Calibrated bolck 3 is put in the endface position of outer measuring staff 1, and clock gauge 4 is packed in the dial framework, is placed on the marble platform; The gauge outfit of clock gauge 4 contacts with calibrated bolck 3 end faces; Press table to zero-bit, move horizontally dial framework, the gauge outfit of clock gauge 4 contacts with the end face of interior measuring staff 2; The end face drop of measuring staff 2 and outer measuring staff 1 in clock gauge 4 is directly read, the computing formula that outer spherical crown radius is definite value r is:
Figure BDA0000092772310000042
Referring to Fig. 3, measuring principle of the present invention is:
1.AE, BD is circular arc ADBE two pitch circles.
Known: AE=a, BD=b asks circular arc ABDE radius r value.
2. in Δ OCD, if known OC=x 1, then can get
Figure BDA0000092772310000043
In Δ OFE, if known OF=x 2, also can get
In the actual measurement, circular arc ABDE center (O) is difficult to confirm, so can't confirm x 1, x 2Value.
3. FC=OC-OF=x in scheming 1-x 2=h
If h is constant; Be and know parameter; Then
Figure BDA0000092772310000045
is definite value, so can obtain r value size:
Figure BDA0000092772310000046
(interior spherical crown);
Figure BDA0000092772310000047
(outer spherical crown).

Claims (7)

1. device of measuring the spherical crown radius; It is characterized in that: the interior coaxial package of outer measuring staff (1) has interior measuring staff (2); Measuring staff (2) can be made the plunger type rectilinear motion in the measuring staff (1) in described outside described; The cylindrical of described outer measuring staff (1) and endoporus and described in the measuring point that contacts with spherical crown surface of the cylindrical of measuring staff (2) be line style, also comprise a clock gauge (4) that is used to measure the end face drop of described outer measuring staff (1) and described interior measuring staff (2).
2. the device of measurement spherical crown radius according to claim 1; It is characterized in that: the end face of the end face of measuring staff (2) and described outer measuring staff (1) realizes that through synchronous processing length difference is a definite value zero in described, and promptly described outer measuring staff (1) is consistent with the length of described interior measuring staff (2).
3. the device of measurement spherical crown radius according to claim 1 and 2 is characterized in that: also comprise at least one calibrated bolck (3), described calibrated bolck (3) is used to fill the end face drop of described outer measuring staff (1) and described interior measuring staff (2).
4. the device of measurement spherical crown radius according to claim 1 and 2 is characterized in that: described outer measuring staff (1) and described interior measuring staff (2) select for use tool steel T 7A to make, and guarantee that through bakingout process hardness reaches 53-58HRC.
5. the device of measurement spherical crown radius according to claim 1 and 2 is characterized in that: the tolerance clearance of the internal diameter of the external diameter of measuring staff (2) and described outer measuring staff (1) is 0.005-0.01mm in described.
6. the measuring method of a spherical crown radius; The device that uses has interior measuring staff (2) by interior the coaxial package of outer measuring staff (1), described in measuring staff (2) can described outside, make the plunger type rectilinear motion in the measuring staff (1), also comprise clock gauge (a 4) composition that is used to measure the end face drop of described outer measuring staff (1) and described interior measuring staff (2); Be in contact with one another through measuring staff cylindrical or endoporus and tested spherical crown surface; Interior measuring staff (2) and outer measuring staff (1) are different because of external diameter, and be different in the spherical crown surface contact site, reads the end face drop of outer measuring staff (1) and interior measuring staff (2) through clock gauge (4); Calculate the measured workpiece radius, it is characterized in that:
(1), measure interior spherical crown radius: the cylindrical of the cylindrical of outer measuring staff (1) and interior measuring staff (2) contacts with tested spherical crown surface simultaneously and forms two pitch circles in the spherical crown; The diameter of the pitch circle that outer measuring staff (1) is corresponding is the diameter a of outer measuring staff (1); The diameter of the pitch circle that interior measuring staff (2) is corresponding is the diameter b of interior measuring staff (2); Then two pitch circle distance h also are the end face drop of the promptly interior measuring staff (2) of definite value with outer measuring staff (1); The end face drop that clock gauge (4) is directly read interior measuring staff (2) and outer measuring staff (1) is two pitch circle distance h, and the computing formula that interior spherical crown radius is definite value r is:
r = [ ( a + b ) 2 + 4 h 2 ] [ ( a - b ) 2 + 4 h 2 ] 8 h ;
(2), measure outer spherical crown radius: the end face of the interior circle of outer measuring staff (1) and interior measuring staff (2) contacts with tested spherical crown surface simultaneously; The interior circle of outer measuring staff (1) forms a pitch circle on the spherical crown surface; The diameter of pitch circle i.e. the internal diameter a of outer measuring staff (1); The spherical crown peak is in plane, interior measuring staff (2) end face place; The spherical crown peak to plane, pitch circle place for definite value h promptly in the end face drop of measuring staff (2) and outer measuring staff (1), clock gauge (4) is directly read the end face drop of interior measuring staff (2) and outer measuring staff (1), the computing formula that outer spherical crown radius is definite value r is:
r = a 2 + 4 h 2 8 h .
7. the measuring method of spherical crown radius according to claim 6 is characterized in that: according to the end face drop of measuring staff (2) in described and outer measuring staff (1) in described measuring staff (2) and outside interpolation corresponding standard piece (3) between the measuring staff (1).
CN2011102806964A 2011-09-20 2011-09-20 Device for measuring radius of spherical crown and measuring method thereof Pending CN102445137A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103292655A (en) * 2013-06-24 2013-09-11 陈磊磊 Computing method of function sizes of benchmark constrained cylinder
CN103292674A (en) * 2013-06-11 2013-09-11 陈磊磊 Method for calculating function size of sphere part
CN103292654A (en) * 2013-06-11 2013-09-11 陈磊磊 Method for calculating function size of cylindrical part
CN104613845A (en) * 2014-12-19 2015-05-13 北京航天控制仪器研究所 High precision sphere diameter in situ measuring device and method
CN105300252A (en) * 2015-11-24 2016-02-03 无锡威孚精密机械制造有限责任公司 High-precision ball diameter testing tool
CN104613845B (en) * 2014-12-19 2018-02-09 北京航天控制仪器研究所 A kind of high-precision sphere diameter on-position measure device and method
CN108917544A (en) * 2018-03-29 2018-11-30 武汉船用机械有限责任公司 A kind of hole measuring device and its application method
CN113670173A (en) * 2021-09-16 2021-11-19 陕西航天时代导航设备有限公司 Ball diameter detection device and method for ball parts
CN114061414A (en) * 2021-12-27 2022-02-18 唐山万士和电子有限公司 Device for measuring curvature radius of crystal oscillator wafer and method for measuring curvature radius of crystal oscillator wafer by using device

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JPH0755405A (en) * 1993-08-20 1995-03-03 Olympus Optical Co Ltd Curvature measuring apparatus for lens
JPH0989507A (en) * 1995-09-21 1997-04-04 Canon Inc Ring for simple spherometer
CN2938024Y (en) * 2006-08-07 2007-08-22 比亚迪股份有限公司 Spherical curvature radius measuring instrument
CN101995203A (en) * 2009-08-10 2011-03-30 重庆川仪自动化股份有限公司 Method for measuring rough machining curvature radius of sapphire concave and convex lenses

Patent Citations (4)

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Publication number Priority date Publication date Assignee Title
JPH0755405A (en) * 1993-08-20 1995-03-03 Olympus Optical Co Ltd Curvature measuring apparatus for lens
JPH0989507A (en) * 1995-09-21 1997-04-04 Canon Inc Ring for simple spherometer
CN2938024Y (en) * 2006-08-07 2007-08-22 比亚迪股份有限公司 Spherical curvature radius measuring instrument
CN101995203A (en) * 2009-08-10 2011-03-30 重庆川仪自动化股份有限公司 Method for measuring rough machining curvature radius of sapphire concave and convex lenses

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103292674A (en) * 2013-06-11 2013-09-11 陈磊磊 Method for calculating function size of sphere part
CN103292654A (en) * 2013-06-11 2013-09-11 陈磊磊 Method for calculating function size of cylindrical part
CN103292674B (en) * 2013-06-11 2015-10-21 桂林电子科技大学 A kind of method calculating function size of sphere part
CN103292654B (en) * 2013-06-11 2015-11-25 桂林电子科技大学 A kind of method calculating function size of cylindrical part
CN103292655B (en) * 2013-06-24 2015-12-02 桂林电子科技大学 A kind of computing method of the cylindrical acts having benchmark to retrain
CN103292655A (en) * 2013-06-24 2013-09-11 陈磊磊 Computing method of function sizes of benchmark constrained cylinder
CN104613845A (en) * 2014-12-19 2015-05-13 北京航天控制仪器研究所 High precision sphere diameter in situ measuring device and method
CN104613845B (en) * 2014-12-19 2018-02-09 北京航天控制仪器研究所 A kind of high-precision sphere diameter on-position measure device and method
CN105300252A (en) * 2015-11-24 2016-02-03 无锡威孚精密机械制造有限责任公司 High-precision ball diameter testing tool
CN108917544A (en) * 2018-03-29 2018-11-30 武汉船用机械有限责任公司 A kind of hole measuring device and its application method
CN108917544B (en) * 2018-03-29 2020-11-10 武汉船用机械有限责任公司 Hole measuring device and using method thereof
CN113670173A (en) * 2021-09-16 2021-11-19 陕西航天时代导航设备有限公司 Ball diameter detection device and method for ball parts
CN114061414A (en) * 2021-12-27 2022-02-18 唐山万士和电子有限公司 Device for measuring curvature radius of crystal oscillator wafer and method for measuring curvature radius of crystal oscillator wafer by using device

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Application publication date: 20120509