Pneumatic measuring tool

Abstract

The utility model relates to a pneumatic measuring tool, which comprises a measuring head provided with a semicircular outer wall. The semicircular outer wall is used for being embedded into a to-be-measured semicircular inner cavity of a workpiece in a matched mode. The measuring head is provided with an air inlet hole and a plurality of exhaust holes, and the plurality of exhaust holes are opposite to the surface of a to-be-measured semicircular inner cavity of a workpiece; an air channel is formed in the measuring head and used for connecting the air inlet and the exhaust hole. Through the arrangement, the measurement principle of the pneumatic measuring tool in the embodiment is a comparison method, the size of the air flow is determined by the size of the gap between the workpiece measurement part and the measurement head, the size of the measured air flow corresponds to the size of the workpiece, the structure is simple, the size of the semicircular inner cavity is measured, the operation is convenient, and the accuracy is high.

Description

Technical Field

[0001] The utility model belongs to the technical field of workpiece size measurement, and particularly relates to a pneumatic measuring tool. Background Art

[0002] For workpieces with semicircular measuring parts, internal diameter gauges and internal micrometers cannot be used due to the semicircular shape; for larger workpieces, secondary clamping is inconvenient and there is a certain degree of error in secondary clamping, so three-coordinate measurement cannot be performed, affecting the operability and accuracy of the measurement. Utility Model Content

[0003] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a pneumatic measuring tool to solve the technical problems of inconvenient measurement and low measurement accuracy for semicircular measuring parts.

[0004] In order to solve the above problems, the technical solution of the utility model is: a pneumatic measuring tool, including a measuring head, which has a semicircular outer wall; the semicircular outer wall is used to match and embed into the semicircular inner cavity to be measured of the workpiece; the measuring head has an air inlet hole and several exhaust holes, and the several exhaust holes are opposite to the surface of the semicircular inner cavity to be measured of the workpiece; an air duct is opened in the measuring head, and the air duct is used to connect the air inlet hole and the exhaust hole.

[0005] Optionally, the measuring head is in a semicircular structure.

[0006] Optionally, a supporting protrusion is provided in the middle of the semicircular outer wall of the measuring head, and the supporting protrusion contacts the surface of the semicircular inner cavity to be measured of the workpiece so that the measuring head swings in the semicircular inner cavity to be measured of the workpiece.

[0007] The surface of the supporting protrusion that contacts the surface of the semicircular inner cavity to be measured of the workpiece is an arc surface, and the axis of the arc surface coincides with the axis of the upper semicircular outer wall of the measuring head.

[0008] Optionally, there are two exhaust holes, which are located on opposite sides of the semicircular outer wall of the measuring head, and there are two air passages, one of which is used to connect the air inlet hole and one of the exhaust holes, and the other air passage is used to connect the air inlet hole and the other exhaust hole.

[0009] Optionally, a plurality of openings are provided on the side end of the measuring head.

[0010] Optionally, two symmetrical openings are opened at a side end of the measuring head.

[0011] Optionally, the air inlet is located at the axis center of the upper semicircular outer wall of the measuring head.

[0012] Optionally, a standard part matched with the measuring head is further included, and the standard part has two pieces, one of which is an upper tolerance and the other is a lower tolerance.

[0013] Optionally, an exhaust groove is provided on the outer wall of the measuring head near the exhaust hole, and an outlet end of the exhaust groove is connected to the side end wall of the measuring head.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The utility model provides a semicircular measuring head, which can be matched and installed in the semicircular inner cavity of the workpiece to be measured. The size of the airflow is determined by the size of the gap between the measuring part of the workpiece and the measuring head. The size of the airflow is measured to correspond to the size of the workpiece. The structure is simple and the measurement is convenient and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the installation of the measuring head and the workpiece in the embodiment;

[0017] Figure 2 A schematic structural diagram of a workpiece in an embodiment;

[0018] Figure 3 Schematic diagram of the installation of the measuring head and the standard component in the embodiment;

[0019] Figure 4 Schematic diagram of the structure of the measuring head in the embodiment;

[0020] Figure 5 Schematic cross-section of the measuring head in the embodiment.

[0021] Figure numerals: 1, measuring head; 11, semicircular outer wall; 12, air inlet; 13, exhaust hole; 14, air duct; 15, supporting protrusion; 16, opening; 17, exhaust groove; 2, workpiece; 21, semicircular inner cavity to be measured; 3, standard part. DETAILED DESCRIPTION

[0022] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0023] Example: Figure 1-Figure 5 As shown, this embodiment provides a pneumatic measuring tool, including a measuring head 1, which has a semicircular outer wall 11; the semicircular outer wall 11 is used to match and embed into the semicircular inner cavity 21 to be measured of the workpiece 2; the measuring head 1 has an air inlet 12 and a plurality of exhaust holes 13, and the plurality of exhaust holes 13 are opposite to the surface of the semicircular inner cavity 21 to be measured of the workpiece 2; an air duct 14 is opened in the measuring head 1, and the air duct 14 is used to connect the air inlet 12 and the exhaust holes 13.

[0024] Through the above-mentioned settings, the measurement principle of the pneumatic measuring instrument in this embodiment is the comparison method: the size of the airflow is determined by the size of the gap between the measuring part of the workpiece 2 and the measuring head 1. The size of the airflow is measured to correspond to the size of the workpiece 2. The structure is simple, and the size of the semicircular inner cavity can be measured. It is easy to operate and has high accuracy. Specifically, the gas enters the airway 14 through the air inlet 12, and then reaches the exhaust hole 13 through the airway 14. The gas is discharged from the exhaust hole 13, and the exhaust hole 13 is the measurement point of the airway 14. The workpiece 2 in this embodiment can be a split-center pump. The pneumatic measuring instrument in this embodiment can be used to measure the semicircular measuring part on the split-center pump. The dimensional tolerance of the measuring part here is IT6 level.

[0025] In a pneumatic measuring tool of this embodiment, the measuring head 1 is in a semicircular structure, which matches the contour of the semicircular inner cavity 21 to be measured of the workpiece 2, facilitating measurement.

[0026] In a pneumatic measuring tool of this embodiment, a support protrusion 15 is formed in the middle of the semicircular outer wall 11 of the measuring head 1. The support protrusion 15 contacts the surface of the semicircular inner cavity 21 to be measured of the workpiece 2, allowing the measuring head 1 to swing within the semicircular inner cavity 21 to be measured of the workpiece 2. This arrangement allows the measuring head 1 to float freely from side to side.

[0027] Optionally, the surface of the supporting protrusion 15 that contacts the surface of the semicircular inner cavity 21 to be measured of the workpiece 2 is an arc surface, and the axis of the arc surface coincides with the axis of the semicircular outer wall 11 of the measuring head 1 .

[0028] In this embodiment of a pneumatic measuring tool, there are two exhaust holes 13, located on opposite sides of the upper semicircular outer wall 11 of the measuring head 1, and two air passages 14, one of which connects the air inlet 12 with one of the exhaust holes 13, and the other connects the air inlet 12 with the other exhaust hole 13. This simple structure facilitates measurement.

[0029] In a pneumatic measuring tool of this embodiment, a plurality of openings 16 are provided on the side end of the measuring head 1 to facilitate taking and placing the measuring head 1, reduce the weight of the measuring head 1, and maintain the structural strength of the measuring head 1.

[0030] In a pneumatic measuring tool of this embodiment, two symmetrical openings 16 are provided on the side ends of the measuring head 1 to keep the center of gravity of the measuring head 1 stable and improve measurement accuracy.

[0031] In the pneumatic measuring tool of this embodiment, the air inlet 12 is located at the axis of the upper semicircular outer wall 11 of the measuring head 1. The structure is regular and the measurement is accurate.

[0032] The pneumatic measuring tool of this embodiment also includes a standard component 3 that cooperates with the measuring head 1. The standard component 3 consists of two parts, one with an upper tolerance and the other with a lower tolerance. The theoretical airflow value is calculated using the airflow measurements of the two standard components 3. Any value between the two theoretical values ​​is considered acceptable, facilitating measurement. Other hole systems can be measured by simply replacing the standard component 3 and the measuring head 1.

[0033] In a pneumatic measuring tool of this embodiment, an exhaust groove 17 is formed on the outer wall of the measuring head 1 near the exhaust hole 13. The outlet end of the exhaust groove 17 is connected to the side wall of the measuring head 1. This facilitates the discharge of gas from the exhaust hole 13, allowing normal measurement and improving measurement accuracy.

Claims

1. A pneumatic measuring tool, characterized in that: The measuring head (1) comprises a measuring head (1), wherein the measuring head (1) has a semicircular outer wall (11); the semicircular outer wall (11) is used to match and be embedded in a semicircular inner cavity (21) to be measured of a workpiece (2); the measuring head (1) has an air inlet (12) and a plurality of exhaust holes (13), wherein the plurality of exhaust holes (13) are opposite to the surface of the semicircular inner cavity (21) to be measured of the workpiece (2); an air duct (14) is provided in the measuring head (1), and the air duct (14) is used to connect the air inlet (12) and the exhaust holes (13).

2. A pneumatic measuring tool according to claim 1, characterized in that: The measuring head (1) is in a semicircular structure.

3. A pneumatic measuring tool according to claim 2, characterized in that: A supporting protrusion (15) is provided in the middle of a semicircular outer wall (11) of the measuring head (1), and the supporting protrusion (15) contacts the surface of a semicircular inner cavity (21) to be measured of the workpiece (2) so that the measuring head (1) swings in the semicircular inner cavity (21) to be measured of the workpiece (2).

4. A pneumatic measuring tool according to claim 3, characterized in that: The surface of the supporting protrusion (15) that contacts the surface of the semicircular inner cavity (21) to be measured of the workpiece (2) is an arc surface, and the axis of the arc surface coincides with the axis of the semicircular outer wall (11) of the measuring head (1).

5. A pneumatic measuring tool according to claim 2, characterized in that: There are two exhaust holes (13), which are respectively located on opposite sides of the upper semicircular outer wall (11) of the measuring head (1). There are two air passages (14), one of which is used to connect the air inlet hole (12) and one of the exhaust holes (13), and the other air passage (14) is used to connect the air inlet hole (12) and the other exhaust hole (13).

6. A pneumatic measuring tool according to claim 2, characterized in that: A plurality of openings (16) are provided on the side end of the measuring head (1).

7. A pneumatic measuring tool according to claim 2, characterized in that: Two symmetrical openings (16) are provided at the side end of the measuring head (1).

8. A pneumatic measuring tool according to claim 1, characterized in that: The air inlet (12) is located at the axis center of the upper semicircular outer wall (11) of the measuring head (1).

9. A pneumatic measuring tool according to claim 1, characterized in that: It also includes a standard part (3) matched with the measuring head (1), the standard part (3) has two parts, one of which is an upper tolerance and the other is a lower tolerance.

10. A pneumatic measuring tool according to claim 1, characterized in that: An exhaust groove (17) is provided on the outer wall of the measuring head (1) near the exhaust hole (13), and the outlet end of the exhaust groove (17) is connected to the side end wall of the measuring head (1).

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