CN114459318B - Device and method for measuring pitch diameter of large-diameter internal thread - Google Patents
Device and method for measuring pitch diameter of large-diameter internal thread Download PDFInfo
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- CN114459318B CN114459318B CN202210032511.6A CN202210032511A CN114459318B CN 114459318 B CN114459318 B CN 114459318B CN 202210032511 A CN202210032511 A CN 202210032511A CN 114459318 B CN114459318 B CN 114459318B
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- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000005259 measurement Methods 0.000 claims abstract description 28
- 238000004364 calculation method Methods 0.000 claims description 7
- 238000000691 measurement method Methods 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 239000000758 substrate Substances 0.000 claims description 3
- 210000003781 tooth socket Anatomy 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000003754 machining Methods 0.000 abstract description 4
- 238000001514 detection method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000010923 batch production Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
- G01B5/08—Measuring arrangements characterised by the use of mechanical techniques for measuring diameters
- G01B5/12—Measuring arrangements characterised by the use of mechanical techniques for measuring diameters internal diameters
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- A Measuring Device Byusing Mechanical Method (AREA)
- Length Measuring Devices With Unspecified Measuring Means (AREA)
Abstract
The invention discloses a large-diameter internal thread pitch diameter measuring device, which comprises a ball head anvil, a differential measuring head, a locking screw and a plurality of extension rods, wherein the ball head anvil is arranged on the ball head; the differential measuring head is in threaded connection with the ball head measuring anvil through a plurality of extension rods, and the end part of a micrometer screw at the front end of the differential measuring head is set to be a ball head; the extension rod connected with the rear end of the differential measuring head is provided with a locking screw which locks the differential measuring head at the end part of the extension rod. The invention has simple and convenient operation and is convenient for the measuring personnel to receive and use; the ball head anvil is matched with the differential measuring head, and the measuring method adopts a method of taking an average value for a plurality of times during measurement, so that the actual measured value is more similar to the true value of the thread to be measured, the measured value is more reliable, and the measuring precision is greatly improved; the device has the advantages of simple integral structure, low manufacturing cost, simple and convenient operation, high measurement accuracy, improved measurement efficiency and convenient wide application in various machining enterprises.
Description
Technical Field
The invention relates to the technical field of thread measurement, in particular to a device and a method for measuring the pitch diameter of a large-diameter internal thread.
Background
The screw thread is used as a most common fastening part in mechanical connection, and the detection of the screw thread is an important link in the production process of the screw thread part; at present, the common internal thread measuring method in the production workshop comprises the following steps: firstly, the comprehensive measurement method adopts a through-end thread gauge to check the screwing property of a thread workpiece according to the Taylor principle, and adopts a stop-end thread gauge to check the manufacturing deviation of a single pitch diameter, thereby being suitable for batch production measurement under workshop production conditions and leading to the thread detection. However, the measuring method can only judge whether the thread is qualified or not, but cannot give specific geometric parameter values of the thread, and is generally applied to small-diameter threads, and the design, manufacture and use of gauges of large-diameter threads are difficult, so that the measurement of the threads is affected; secondly, the thread profile template is adopted for measurement, the method judges the thread profile and the inner diameter size by means of light transmittance, the measurement accuracy is very low, the error is large, and the machining efficiency is very low due to the fact that the internal and external threads are matched with a machining mode.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a device and a method for measuring the pitch diameter of a large-diameter internal thread, which are simple to operate and high in measurement efficiency, and are particularly suitable for precise and efficient measurement in the production of the large-diameter external thread.
The technical scheme adopted by the invention is as follows:
The large-diameter internal thread pitch diameter measuring device comprises a ball head anvil, a differential measuring head, a locking screw and a plurality of extension rods;
One end of the ball head anvil is provided with a ball measuring head, and the other end of the ball head anvil is provided with an external thread connecting part; one end of the extension rod is provided with an internal threaded hole, the other end of the extension rod is provided with an external threaded connection part, the differential measuring head is in threaded connection with the ball head measuring anvil through a plurality of extension rods, and the end part of a micrometer screw rod at the front end of the differential measuring head is provided with a ball head; the extension rod connected with the rear end of the differential measuring head is provided with a locking screw which locks the differential measuring head at the end part of the extension rod.
Specifically, knurling is arranged on the outer edges of the locking screw, the ball head anvil, the differential measuring head and the extension rod; the screw connection screwing is convenient.
Specifically, the ball head anvil is made of hard alloy.
Specifically, the plurality of extension bars are provided with a plurality of different lengths.
A method for measuring pitch diameter of large-diameter internal threads; the method comprises the following specific steps:
Step one: substituting the pitch P and the tooth angle alpha of the large-diameter internal thread to be measured into Selecting a ball head anvil of a ball head radius SR of the spherical measurement;
Step two: according to the relevant size of the large-diameter internal thread to be measured and the ball head radius SR of the ball head anvil, calculating and predicting a measured value M of the large-diameter internal thread to be measured; the specific calculation method comprises the following steps:
M＝D3+X＝D3/2+D2/2+AB
AB＝AK-BK＝AK-(OK-OB)
in the case of the triangular AFK,
In the case of the triangle-shaped OCK,
Also because ob=oc=sr
Thus, the first and second substrates are bonded together,
Simplifying and simplifying
Bringing the tooth angle alpha of the metric triangle thread into the formula (1) to calculate an M value;
Wherein: the point O is the center point of the measuring ball, the point A is the intersection point of the internal thread pitch diameter D 2 line and the axis of the differential measuring head, the point B is the intersection point of the spherical measuring head round line and the axis of the differential measuring head, the point C is the tangent point of the spherical measuring head and the thread side, the point F is the intersection point of the internal thread pitch diameter D 2 line and the thread side, and the point D 3 is the internal thread minor diameter;
Step three: calculating a predicted measured M value of the thread to be measured according to the second step, and selecting an extension rod and a differential measuring head which meet the measurement range of the large-diameter internal thread;
step four: the selected ball head anvil and the differential measuring head are connected with a plurality of extension rods with corresponding lengths through threads, the total length L after assembly is close to an M value and smaller than the M value, and the difference value between the total length L and the M value is smaller than the measuring range of the differential measuring head; the length and the size of the connected large-diameter internal thread measuring device are calibrated by using an external micrometer, a differential tube of a differential measuring head is locked at a zero position and is locked by a locking screw during calibration, the calibration measurement is performed for more than 3 times, an L average is taken and recorded, and the calibration of the large-diameter internal thread measuring device is completed;
step five: placing a large-diameter internal thread measuring device between internal threads to be detected, placing a spherical measuring head of a ball head measuring anvil in an internal thread tooth groove to be tangential with two side surfaces of the thread tooth groove, adjusting the extending length of a differential measuring head at the other end of an extension rod to enable the ball head of a micro-measuring screw to be in tangential contact with a small-diameter cylindrical surface of the large-diameter internal thread to be detected, and tightening a screw to fix the differential measuring head; reading the scale on the differential measuring head, wherein the measured M Measuring value is the calibration size L plus the differential measuring head reading;
Step six: repeating the step five to obtain an M Measuring value once every 90 degrees of rotation of the ball head anvil along the tooth socket spiral, repeating the step i for i times, wherein i is a natural number, and obtaining i+1 measured M Measuring values;
Step seven: the data of the step six are calculated to obtain an average value M X by the following relation:
step eight: the actual measurement value D 2 Measuring of the pitch diameter of the internal thread with the large diameter is obtained through calculation:
by adopting the technical scheme, the invention has the following advantages:
the invention has simple and convenient operation and is convenient for the measuring personnel to receive and use; the ball head anvil is matched with the differential measuring head, and the measuring method adopts a method of taking an average value for a plurality of times during measurement, so that the actual measured value is more similar to the true value of the thread to be measured, the measured value is more reliable, and the measuring precision is greatly improved; the device has the advantages of simple integral structure, low manufacturing cost, simple and convenient operation, high measurement accuracy, improved measurement efficiency and convenient wide application in various machining enterprises.
Drawings
Fig. 1 is an overall schematic of the invention in use.
Fig. 2 is a schematic diagram of the estimation principle in the second step of the present invention.
Fig. 3 is an overall schematic diagram of the measuring device of the present invention.
Fig. 4 is a schematic view of a ball end anvil of the present invention.
Fig. 5 is a schematic view of the extension rod of the present invention.
In the figure: 1-ball head anvil, 2-differential measuring head, 21-differential cylinder, 3-locking screw, 4-extension rod and 5-large diameter internal thread to be measured.
Detailed Description
The present invention is further explained below with reference to the drawings and examples, which are not to be construed as limiting the scope of the invention, and the purpose of the present invention is to protect all technical improvements within the scope of the invention.
A large-diameter internal thread pitch diameter measuring device combined with figures 1-5 comprises a ball head anvil 1, a differential measuring head 2, a locking screw 3 and a plurality of extension rods 4.
One end of the ball head anvil 1 is provided with a spherical measuring head, the ball head anvil 1 is made of hard alloy, and the other end is provided with an external thread connecting part; one end of the extension rod 4 is provided with an internal threaded hole, the other end of the extension rod is provided with an external threaded connection part, the differential measuring head 2 and the ball head measuring anvil 1 are in threaded connection through a plurality of extension rods 4, a plurality of extension rods 4 are provided with a plurality of different lengths, and the end part of a micrometer screw at the front end of the differential measuring head 2 is provided with a ball head; the extension rod 4 connected with the rear end of the differential measuring head 2 is provided with a locking screw 3, and the differential measuring head 2 is locked at the end part of the extension rod 4 by the locking screw 3.
Preferably, knurling is arranged on the outer edges of the locking screw 3, the ball head anvil 1, the differential measuring head 2 and the extension rod 4; the screw connection screwing is convenient.
A method for measuring pitch diameter of large-diameter internal threads; the method comprises the following specific steps:
Step one: substituting the pitch P and the tooth angle alpha of the large-diameter internal thread 5 to be measured into A ball head anvil 1 of ball head radius SR of the ball measurement is selected.
Step two: according to the relative size of the large-diameter internal thread 5 to be measured and the ball radius SR of the ball measuring anvil 1, a measured value M of the thread to be measured is estimated through calculation; the specific calculation method comprises the following steps:
M＝D3+X＝D3/2+D2/2+AB
AB＝AK-BK＝AK-(OK-OB)
in the case of the triangular AFK,
In the case of the triangle-shaped OCK,
Also because ob=oc=sr
Thus, the first and second substrates are bonded together,
Simplifying and simplifying
Bringing the tooth angle alpha of the metric triangle thread into the formula (1) to calculate an M value;
Wherein: the point O is the center point of the measuring ball, the point A is the intersection point of the internal thread pitch diameter D 2 line and the axis of the differential measuring head 2, the point B is the intersection point of the spherical measuring head round line and the axis of the differential measuring head 2, the point C is the tangent point of the spherical measuring head and the thread side, the point F is the intersection point of the internal thread pitch diameter D 2 line and the thread side, and the point D 3 is the internal thread minor diameter.
Step three: and D, calculating a predicted measurement M value of the large-diameter internal thread 5 to be measured according to the second step, and selecting the extension rod 4 and the differential measuring head 2 which meet the measurement range of the large-diameter internal thread.
Step four: the selected ball head anvil 1 and the differential measuring head 2 are connected with a plurality of extension rods 4 with corresponding lengths through threads, the total length L after assembly is close to an M value and smaller than the M value, and the difference value between the total length L and the M value is smaller than the measuring range of the differential measuring head 2; the length and the size of the connected large-diameter internal thread measuring device are calibrated by using an outside micrometer, the differential cylinder 21 of the differential measuring head 2 is locked at the zero position and is locked by the locking screw 3 during calibration, the calibration is performed for more than 3 times, the L average is taken and recorded, and the calibration of the large-diameter internal thread measuring device is completed.
Step five: placing a large-diameter internal thread measuring device between internal threads to be detected, placing a spherical measuring head of a ball head measuring anvil 1 in an internal thread tooth groove to be tangential with two side surfaces of the thread tooth groove, adjusting the extending length of a differential measuring head 2 at the other end of an extension rod 4 to enable the ball head of a micro-measuring screw to be in tangential contact with a small-diameter cylindrical surface of the large-diameter internal thread to be detected, and tightening a tightening screw to fix the differential measuring head 2; the scale on the differential gauge head 2 is read, and the measured M Measuring value is the calibration size L plus the differential gauge head 2 reading.
Step six: repeating the step five along the tooth socket spiral every 90 degrees to obtain an M Measuring value, repeating the step i times, wherein i is a natural number, and obtaining i+1 measured M Measuring values.
Step seven: the data of the step six are calculated to obtain an average value M X by the following relation:
Step eight: the actual measurement value D 2 Measuring of the pitch diameter of the large-diameter internal thread 5 to be measured is obtained through calculation:
The invention is not described in detail in the prior art.
The embodiments selected herein for the purposes of disclosing the invention are presently considered to be suitable, but it is to be understood that the invention is intended to include all such variations and modifications as fall within the spirit and scope of the invention.
Claims (4)
1. A measuring method of a large-diameter internal thread pitch diameter measuring device is characterized by comprising the following steps of: the method comprises the following specific steps:
Step one: substituting the pitch P and the tooth angle alpha of the large-diameter internal thread to be measured into Selecting a ball head anvil of a ball head radius SR of the spherical measurement;
step two: according to the relevant size of the large-diameter internal thread to be measured and the ball head radius SR of the ball head anvil, calculating and predicting a measured value M of the large-diameter internal thread to be measured; the specific calculation method comprises the following steps:
M＝D3+X＝D3/2+D2/2+AB
AB＝AK-BK＝AK-(OK-OB)
in the case of the triangular AFK,
In the case of the triangle-shaped OCK,
Also because ob=oc=sr
Thus, the first and second substrates are bonded together,
Simplifying and simplifying
Bringing the tooth angle alpha of the metric triangle thread into the formula (1) to calculate an M value;
Wherein: the point O is the center point of the measuring ball, the point A is the intersection point of the internal thread pitch diameter D 2 line and the axis of the differential measuring head, the point B is the intersection point of the spherical measuring head round line and the axis of the differential measuring head, the point C is the tangent point of the spherical measuring head and the thread side, the point F is the intersection point of the internal thread pitch diameter D 2 line and the thread side, and the point D 3 is the internal thread minor diameter;
Step three: calculating a predicted measured M value of the thread to be measured according to the second step, and selecting an extension rod and a differential measuring head which meet the measurement range of the large-diameter internal thread;
step four: the selected ball head anvil and the differential measuring head are connected with a plurality of extension rods with corresponding lengths through threads, the total length L after assembly is close to an M value and smaller than the M value, and the difference value between the total length L and the M value is smaller than the measuring range of the differential measuring head; the length and the size of the connected large-diameter internal thread measuring device are calibrated by using an external micrometer, a differential tube of a differential measuring head is locked at a zero position and is locked by a locking screw during calibration, the calibration measurement is performed for more than 3 times, an L average is taken and recorded, and the calibration of the large-diameter internal thread measuring device is completed;
step five: placing a large-diameter internal thread measuring device between internal threads to be detected, placing a spherical measuring head of a ball head measuring anvil in an internal thread tooth groove to be tangential with two side surfaces of the thread tooth groove, adjusting the extending length of a differential measuring head at the other end of an extension rod to enable the ball head of a micro-measuring screw to be in tangential contact with a small-diameter cylindrical surface of the large-diameter internal thread to be detected, and tightening a screw to fix the differential measuring head; reading the scale on the differential measuring head, wherein the measured M Measuring value is the calibration size L plus the differential measuring head reading;
Step six: repeating the step five to obtain an M Measuring value once every 90 degrees of rotation of the ball head anvil along the tooth socket spiral, repeating the step i for i times, wherein i is a natural number, and obtaining i+1 measured M Measuring values;
Step seven: the data of the step six are calculated to obtain an average value M X by the following relation:
Step eight: the actual measurement value D 2 Measuring of the pitch diameter of the large-diameter internal thread to be measured is obtained through calculation:
The large-diameter internal thread pitch diameter measuring device comprises a ball head anvil, a differential measuring head, a locking screw and a plurality of extension rods;
One end of the ball head anvil is provided with a ball measuring head, and the other end of the ball head anvil is provided with an external thread connecting part; one end of the extension rod is provided with an internal threaded hole, the other end of the extension rod is provided with an external threaded connection part, the differential measuring head is in threaded connection with the ball head measuring anvil through a plurality of extension rods, and the end part of a micrometer screw rod at the front end of the differential measuring head is provided with a ball head; the extension rod connected with the rear end of the differential measuring head is provided with a locking screw which locks the differential measuring head at the end part of the extension rod.
2. The measurement method of the large-diameter internal thread pitch diameter measurement device according to claim 1, wherein: the locking screw, the ball head anvil, the differential measuring head and the outer edge of the extension rod are all provided with knurls.
3. The measurement method of the large-diameter internal thread pitch diameter measurement device according to claim 1, wherein: the ball head anvil is made of hard alloy.
4. The measurement method of the large-diameter internal thread pitch diameter measurement device according to claim 1, wherein: the extension rods are provided with a plurality of different lengths.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210032511.6A CN114459318B (en) | 2022-01-12 | 2022-01-12 | Device and method for measuring pitch diameter of large-diameter internal thread |
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| CN202210032511.6A CN114459318B (en) | 2022-01-12 | 2022-01-12 | Device and method for measuring pitch diameter of large-diameter internal thread |
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| Publication Number | Publication Date |
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| CN114459318A CN114459318A (en) | 2022-05-10 |
| CN114459318B true CN114459318B (en) | 2024-04-26 |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19808825A1 (en) * | 1998-03-03 | 1999-09-09 | Optische Koordinatenmestechnik | Measuring dimensions of tapered thread using co-ordinate measuring machine |
| CN104976939A (en) * | 2014-04-10 | 2015-10-14 | 哈尔滨飞机工业集团有限责任公司 | Zigzag mainshaft nut pitch diameter measurement method |
| CN204924129U (en) * | 2015-07-31 | 2015-12-30 | 中原特钢股份有限公司 | Interior pitch diameter measuring tool |
| CN105423969A (en) * | 2015-11-18 | 2016-03-23 | 沈阳黎明航空发动机(集团)有限责任公司 | Method for measuring geometric parameters of large-diameter thread form |
| CN205561720U (en) * | 2016-02-05 | 2016-09-07 | 苏州工业职业技术学院 | Bore diameter measures tool |
| CN106052576A (en) * | 2016-04-22 | 2016-10-26 | Iac几何工程师有限公司 | screw-thread measuring device and method |
| JP6216432B1 (en) * | 2016-09-27 | 2017-10-18 | 星和電機株式会社 | Female thread effective diameter measuring instrument |
| CN111928809A (en) * | 2020-08-03 | 2020-11-13 | 淮安市迈奕机电设备有限公司 | Method for measuring pitch diameter of thread by utilizing threaded roller measuring anvil |
-
2022
- 2022-01-12 CN CN202210032511.6A patent/CN114459318B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19808825A1 (en) * | 1998-03-03 | 1999-09-09 | Optische Koordinatenmestechnik | Measuring dimensions of tapered thread using co-ordinate measuring machine |
| CN104976939A (en) * | 2014-04-10 | 2015-10-14 | 哈尔滨飞机工业集团有限责任公司 | Zigzag mainshaft nut pitch diameter measurement method |
| CN204924129U (en) * | 2015-07-31 | 2015-12-30 | 中原特钢股份有限公司 | Interior pitch diameter measuring tool |
| CN105423969A (en) * | 2015-11-18 | 2016-03-23 | 沈阳黎明航空发动机(集团)有限责任公司 | Method for measuring geometric parameters of large-diameter thread form |
| CN205561720U (en) * | 2016-02-05 | 2016-09-07 | 苏州工业职业技术学院 | Bore diameter measures tool |
| CN106052576A (en) * | 2016-04-22 | 2016-10-26 | Iac几何工程师有限公司 | screw-thread measuring device and method |
| JP6216432B1 (en) * | 2016-09-27 | 2017-10-18 | 星和電機株式会社 | Female thread effective diameter measuring instrument |
| CN111928809A (en) * | 2020-08-03 | 2020-11-13 | 淮安市迈奕机电设备有限公司 | Method for measuring pitch diameter of thread by utilizing threaded roller measuring anvil |
Non-Patent Citations (1)
| Title |
|---|
| 大螺纹精密加工及检测技术研究;张恒 等;检测与质量(第3期);第92-95页 * |
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