Pneumatic plug gauge and measuring system

Patent metadata

Field	Value
Publication number	US-10775162-B2
Application number	US-201515533703-A
Country	US
Kind code	B2
Filing date	Oct 27, 2015
Priority date	Dec 8, 2014
Publication date	Sep 15, 2020
Grant date	Sep 15, 2020

Abstract

A pneumatic plug gauge has been developed in the context of the invention. This plug gauge comprises a first measuring channel which can be connected to a pressure medium source and opens into a first outlet for the pressure medium, which outlet can be directed to a surface of the workpiece to be tested. According to the invention, this plug gauge is designed to determine the tilt angle between a section on the surface thereof and a region opposite this section on the surface of the workpiece by virtue of the first outlet being arranged at one end of the section and at least one second outlet being provided, which second outlet is arranged at the other end of the section. It has been recognized that the admittedly high precision of pneumatic length measurements can be converted in a particularly advantageous manner to high precision of the angle measurement in this manner. The tilt angle can be measured at least with an accuracy of less than one tenth of a degree. At the same time, the measurement is fast enough for 100% control in mass production. The plug gauge is the central element in the measuring system and in the method, to which the invention likewise relates.

First claim

The invention claimed is:

1. A pneumatic plug gauge (M), comprising:
a first measurement channel ( 1 ) that is configured to be connected to a pressure medium source ( 7 a , 7 b ) and that opens into a first outlet ( 1 a ) for the pressure medium that can be directed at a surface of a workpiece to be checked ( 3 ),
wherein the plug gauge (M) is configured for determining the angle of inclination (α-β) between a path (A) on a surface of the plug gauge (M) and a region ( 1 b , 2 b , B) on the surface of the workpiece ( 3 ) opposite said path (A) by the first outlet ( 1 a ) being disposed at one end of the path (A) and by the first outlet ( 1 a ) being movable to the other end of the path (A) or at least one second outlet ( 2 a ) being provided that is disposed at the other end the path (A), characterized in that the plug gauge is of a rotation symmetrical form about an axis of rotation, and wherein the plug gauge has a circular cross-section perpendicular to the axis of rotation, and wherein the plug gauge is of a conical form, at least in a region in which the path (A) runs between the first outlet ( 1 a ) and the at least one second outlet ( 2 a ).

2. The pneumatic plug gauge (M) as claimed in claim 1 , characterized in that a second independent measurement channel ( 2 ) is provided that opens at the second outlet ( 2 a ).

3. The pneumatic plug gauge (M) as claimed in claim 1 , characterized in that the plug gauge comprises at least one stop ( 5 ) for making contact with the workpiece ( 3 ).

4. The pneumatic plug gauge (M) as claimed in claim 1 , wherein the plug gauge is configured to be rotated about the axis of rotation so that the angle of inclination can be measured as a function of the angle of rotation.

5. The pneumatic plug gauge (M) as claimed in claim 1 , wherein the plug gauge has at least an end portion that is conical.

6. The pneumatic plug gauge (M) as claimed in claim 1 , further comprising the workpiece ( 3 ), wherein the surface of the plug gauge (M) faces away from the axis of rotation, and wherein the surface of the workpiece ( 3 ) faces toward the axis of rotation.

7. The pneumatic plug gauge (M) as claimed in claim 1 , wherein the pneumatic plug gauge (M) includes only the first outlet ( 1 a ), and is configured for determining the angle of inclination (α-β) between the path (A) on the surface of the plug gauge (M) and the region ( 1 b , 2 b , B) on the surface of the workpiece ( 3 ) opposite said path (A) by the first outlet ( 1 a ) being moved to the other end of the path (A).

8. The pneumatic plug gauge (M) as claimed in claim 1 , wherein the pneumatic plug gauge (M) is configured for determining the angle of inclination (α-β) between the path (A) on the surface of the plug gauge (M) and the region ( 1 b , 2 b , B) on the surface of the workpiece ( 3 ) opposite said path (A) by the at least one second outlet ( 2 a ) being disposed at the other end the path (A).

9. The pneumatic plug gauge as claimed in claim 1 , characterized in that the plug gauge has at least one opening ( 4 a , 4 b , 4 c ), into which the pressure medium can penetrate via an intermediate space (D) between the workpiece ( 3 ) and the outlet ( 1 a , 2 a ) and can then flow out unchoked.

10. The pneumatic plug gauge (M) as claimed in claim 3 , characterized in that the path (A) between the two outlets ( 1 a , 2 a ) leads over at least one opening ( 4 b ).

11. A measurement system ( 6 ) for determining an angle (α-β) on a surface of a workpiece ( 3 ), comprising a pneumatic plug gauge (M) as claimed in claim 1 , at least one pressure medium source ( 7 a , 7 b ) with a choked output ( 7 c , 7 d ) leading to the outlets, and at least one pressure measuring device ( 8 a , 8 b ) connected between the output and the outlets.

12. The measurement system ( 6 ) as claimed in claim 11 , characterized in that means are provided for alternately subjecting the two outlets ( 1 a , 2 a ) to the pressure medium.

13. The measurement system ( 6 ) as claimed in claim 7 , characterized in that the pressure measuring device ( 8 a , 8 b ) is connected to an analysis unit ( 9 ) configured to determine the angle (α-β) from measured pressures.

14. A method for pneumatically determining a tilt angle (αβ) between a path (A) in space and a region ( 1 b , 2 b , B) on a surface of a workpiece to be checked ( 3 ) opposite said path (A) with a pneumatic, rotation symmetrical plug gauge (M), wherein the plug gauge is rotation symmetrical about an axis of rotation and has a circular cross-section perpendicular to the axis of rotation, and wherein said plug gauge (M) comprises at least one measurement channel ( 1 , 2 ) that is subjected to a pressure medium by means of a choked output ( 7 c , 7 d ) of a pressure medium source ( 7 a , 7 b ) and that opens at an outlet ( 1 a , 2 a ) that is directed towards the surface of the workpiece ( 3 ), and wherein the plug gauge is of a conical form, at least in a region in which the path (A) runs between the outlet ( 1 a , 2 a ) and at least one second outlet ( 1 a , 2 a ), the method comprising:
measuring a respective pressure between the choked output ( 7 c , 7 d ) of the pressure medium source ( 7 a , 7 b ) and the outlet ( 1 a , 2 a ) of the measurement channel ( 1 , 2 ) at both end points of the path (A) to determine the tilt angle; and
rotating the plug gauge within the workpiece to measure the tilt angle as a function of the angle of rotation of the plug gauge.

15. The method as claimed in claim 14 , characterized in that the path (A) is oriented in space parallel to the surface of the workpiece ( 3 ) to within an angle of a maximum of 1 degree.

16. The method as claimed in claim 14 , characterized in that the measurement channel ( 1 , 2 ) is subjected to a pressure between 2 and 4 bar and the outlet ( 1 a , 2 a ) is guided to the surface of the workpiece ( 3 ) at both points of the path (A) at a distance between 10 μm and 40 μm.

17. The method as claimed in claim 14 , characterized in that the measurement channel ( 1 , 2 ) is subjected to a pressure between 2 and 4 bar and the outlet ( 1 a , 2 a ) is guided to the surface of the workpiece ( 3 ) at both points of the path (A) at a distance between 20 μm and 30 μm.

18. The method as claimed in claim 14 , wherein the step of rotating includes rotating the plug gauge (M) about the axis of rotation.

19. The method as claimed in claim 14 , wherein the plug gauge (M) comprises a first measurement channel ( 1 ) that is configured to be connected to a pressure medium source ( 7 a , 7 b ) and that opens into a first outlet ( 1 a ) for the pressure medium that can be directed at the surface of a workpiece to be checked ( 3 ), wherein the plug gauge (M) is configured for determining the angle of inclination (α-β) between the path (A) on a surface of the plug gauge (M) and a region ( 1 b , 2 b , B) on the surface of the workpiece ( 3 ) opposite said path (A) by the first outlet ( 1 a ) being disposed at one end of the path (A) and by the first outlet ( 1 a ) being movable to the other end of the path (A) or the at least one second outlet ( 2 a ) being provided that is disposed at the other end the path (A).

20. The method as claimed in claim 19 , the method further comprising carrying out the method using at least one pressure medium source ( 7 a , 7 b ) with a choked output ( 7 c , 7 d ) leading to the outlets, and at least o

Assignees

• Bosch Gmbh Robert

Inventors

• Schruefer Andreas
• Schmidtlein Christoph
• Beck Herbert
• Weickmann Johannes

Classifications

• G01B13/18 Primary

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• B21D5/006

  combined with measuring of bends · CPC title

• B21D5/0209

  Tools therefor · CPC title

• G01B5/012

  Contact-making feeler heads therefor · CPC title