CN113670162A

CN113670162A - Method for measuring countersunk head height P value of countersunk head screw

Info

Publication number: CN113670162A
Application number: CN202110723895.1A
Authority: CN
Inventors: 田冬英; 梁华; 张会芳
Original assignee: China Aviation Industry Standard Parts Manufacturing Co Ltd
Current assignee: China Aviation Industry Standard Parts Manufacturing Co Ltd
Priority date: 2021-06-29
Filing date: 2021-06-29
Publication date: 2021-11-19

Abstract

The invention discloses a method for measuring the countersunk head height P value of a countersunk head screw, which comprises the following steps: before detecting parts, the actual height value of the special bushing is actually measured by a digital display vernier caliper, namely L_{Measured value}(ii) a Then the measured part is put into a special bushing, two measuring claws of the digital display vernier caliper respectively clamp the countersunk end face of the part and the lower end face of the bushing, the sum of the measured value L of the bushing and the measured value P of the part is measured, the reading value of the digital display vernier caliper in the digital display vernier caliper is observed, and if the reading value is L, the reading value is L_{Measured value}+Pmin～L_{Measured value}+ Pmax, the measured part (3) is judged to be qualified, and if the reading value is L_{Measured value}+Pmin～L_{Measured value}If the + Pmax range is out, the tested part (3) is judged to be unqualified. Digital display vernier caliper reading and lining L_{Measured value}The difference is the actual measurement value of the height P of the countersunk head of the part. The invention saves cost, shortens production period and can quantitatively judge whether the product is qualified or not.

Description

Method for measuring countersunk head height P value of countersunk head screw

Technical Field

The invention belongs to the technical field of measurement, and particularly relates to a method for measuring a countersunk head height P value of a countersunk head screw.

Background

The countersunk head height P value of the countersunk head screw is measured by using a bushing and a clamping plate in a matching way, as shown in figure 1, according to the principle of a smooth limit gauge, namely, the countersunk head is open at one end and is closed at the other end, the size of the part is judged to be qualified. The measuring method is that a part with one specification simultaneously uses a bushing and a clamping plate, and the bushing and the clamping plate are not necessary. The method can only qualitatively judge whether the product size is qualified, but wastes manpower, material resources, financial resources and time, and often delays the production cycle.

Disclosure of Invention

The invention aims to overcome the defects and provide a method for measuring the countersunk head height P value of the countersunk head screw, which saves cost, shortens the production period and quantitatively judges whether the product is qualified.

The purpose of the invention and the main technical problem of solving the invention are realized by adopting the following technical scheme:

a method for measuring the countersunk head height P value of a countersunk head screw comprises the following steps:

1) measuring the actual value of the special bushing; before detecting parts, the actual height value of the special bushing is actually measured by a digital display vernier caliper, namely L_{Measured value}；

2) And calculating the limit size: 3) judging whether the part is qualified or not, namely putting the part to be measured into a special bushing, clamping the countersunk end face and the lower end face of the part by two measuring claws of the vernier caliper respectively, observing the reading value of the vernier caliper if the reading value is L + Pmin and L + Pmax, and judging whether the part is qualified or not_{Measured value}+Pmin～L_{Measured value}+ PmaxL + Pmin-L + Pmax, the measured part is judged to be qualified, and if the reading value is L_{Measured value}+Pmin～L_{Measured value}If the measured part is out of the range of + Pmax, the measured part is judged to be unqualified;

4) and calculating the actually measured countersunk head height P value of the measured part: the difference between the value read by the digital display vernier caliper and the actual value of the bush L is the actual value of the countersunk head height P of the part.

The P value is in the range of Pmin and Pmax, the maximum value is Pmax, the minimum value is Pmin, and if the reading value is L_{Measured value}+Pmin～L_{Measured value}If the measured part is qualified within the range of + Pmax, the reading value is L_{Measured value}+Pmin～L_{Measured value}And if the measured part is out of the range of + Pmax, judging the measured part as unqualified.

Compared with the prior art, the invention has obvious beneficial effects; the technical scheme shows that: the invention uses the vernier caliper before detecting the partActually measuring the actual height value of the special bushing, namely an L measured value; then the measured part is put into a special bushing, two measuring claws of the vernier caliper respectively clamp the countersunk end face of the part and the lower end face of the bushing, the sum of the measured value L of the bushing and the measured value P of the part is measured, the reading value of the vernier caliper is observed, and if the reading value is L, the reading value is_{Measured value}+Pmin～L_{Measured value}+ Pmax, the measured part is judged to be qualified, and if the reading value is L_{Measured value}+Pmin～L_{Measured value}And if the + Pmaxx range is out of the range, judging the tested part as unqualified. Vernier caliper reading and bushing L_{Measured value}The difference is the actual measurement value of the height P of the countersunk head of the part. The special card in figure 4 is replaced by a vernier caliper. When the measuring method is used for detecting the height dimension of the countersunk head of the part, only a special bushing and a digital display vernier caliper are needed, and a special clamping plate is not needed. D is the diameter of the middle part of the countersunk head of the part, D is the diameter of the lower part of the part, the vernier caliper is easy to acquire and purchase, the purchasing period is short, and different products only need to be matched with one digital display vernier caliper. The cost is saved, the production period is shortened, and whether the product is qualified or not is judged quantitatively.

Drawings

FIG. 1 is a state diagram of the present invention in use;

FIG. 2 is a schematic view of the components tested according to the present invention;

FIG. 3 is a schematic view of a part under test according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an original measurement method.

In the drawings, reference numerals

1. The digital display vernier caliper comprises a bushing, 2, a digital display vernier caliper, 3, parts, 4, a clamping plate, 5, an end through part, 6 and a stop end.

Detailed Description

The details of the embodiments, structures, features and functions according to the present invention are set forth in the accompanying drawings and the preferred embodiments.

The nail head height value of the tested part 3 is P =2.43+0.10mm, Pmin =2.43mm, and Pmax =2.53 mm. Before detecting the part, firstly, actually measuring the actual height L of the bush 1 with the actual measurement value =30.00mm, putting the part 2 into the bush, respectively clamping the countersunk end face of the part 3 and the lower end face of the bush 1 by two measuring claws of the digital display vernier caliper 3, and measuring the part 2 shown in the figure 4Measuring, observing the numerical value read by the numerical display caliper in the numerical display vernier caliper 3, if the numerical value read is within the range of 30.00+2.43=32.43 mm-30.00 +2.53=32.53mm, the measured part is qualified, and subtracting the actual height value (L) of the special bushing from the caliper reading_{Measured value}=30.00 mm) is the measured value of the part.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. A method for measuring the countersunk head height P value of a countersunk head screw comprises the following steps:

1) measuring the actual value of the special bushing; before detecting the part (3), a vernier caliper (2) is used for actually measuring the actual height value, namely L, of the special bushing (1)_{Measured value}；

2) And calculating the limit size: the minimum limit size is L + Pmin, and the maximum limit size is L + Pmax;

3) and judging whether the part is qualified, namely putting the part to be measured into a special bushing, clamping the countersunk end face of the part and the lower end face of the bushing by two measuring claws of the vernier caliper respectively, observing the reading value of the vernier caliper if the reading value is L_{Measured value}+Pmin～L_{Measured value}+ Pmax, the measured part is judged to be qualified, and if the reading value is L_{Measured value}+Pmin～L_{Measured value}If the range of + Pmaxx is out, the tested part is judged to be unqualified;

4) and calculating the actual countersunk head height P value of the measured part: vernier caliper reading value and bushing L_{Measured value}The difference is the actual measurement value of the height P of the countersunk head of the part.

2. A method of measuring the countersunk-head height P of a countersunk screw as claimed in claim 1, in which; the P value in the step 2 or 3 is within the range of Pmin and Pmax, Pmin is the minimum value, Pmax is the maximum value, and the digital display vernier caliper readsIf the value is at L_{Measured value}+Pmin～L_{Measured value}If the measured part (3) is qualified within the range of + Pmax, the reading value is L_{Measured value}+Pmin～L_{Measured value}And if the + Pmax range is out of the range, the measured part (3) is judged to be unqualified.