Method, device and stamp for manufacturing a reference nozzle in a device for pneumatic measurement technology

Abstract

Method for manufacturing a reference nozzle (1) in a device for pneumatic measurement technology, which has a passage (3) with an inner contour (4, 5) in a nozzle body (2), characterized by the following steps: • A cylindrical passage (6) is formed in or out of the nozzle body (2). • A pin (7) is inserted into the passage (6) which at least partially has the inner contour (4, 5) of the desired opening (3). • The pin (7) is pressed into the nozzle body (2.2) in such a way that material of the nozzle body (2.2) surrounds the pin (7) and thus the desired passage (3) with the desired inner contour (4, 5) is formed.

Description

[0001] The invention relates to a method, a device for producing a reference nozzle in a device for pneumatic measurement technology according to the preamble of claims 1 and 5, and an embossing die for the method according to claim 6. State of the art

[0002] Devices in pneumatic metrology are used, for example, to measure the inner or outer diameter of a workpiece. A measuring fluid, particularly air, is fed into a flow channel. The air flows through the channel along a specific direction. The air is pressurized, first passing through a reference nozzle located in the flow channel, and then flowing to a measuring nozzle that is effectively connected to the channel. The air flows from the measuring nozzle into a gap between the nozzle and the workpiece, which acts as a throttling point. The size of this gap, which depends on the workpiece geometry, influences the throttling effect of the gap and thus the second pressure downstream of the reference nozzle.In this way, the workpiece geometry can be determined by measuring the first and second measuring fluid pressures.

[0003] Such a device is known from DE 102 36 402 A1. Further reference is made to DE 197 33 984 A1, DE 199 26 946 A1 and DE 101 55 135 B4 as further examples of prior art.

[0004] For a large number of workpieces, it is necessary to manufacture workpiece dimensions with extremely tight tolerances and to verify compliance with these dimensions. This requires, in particular, that the reference nozzle be very precisely shaped and that its internal contour be produced with high repeatability. Up to now, this has been achieved through various machining operations, especially drilling, grinding, honing, etc. However, the required accuracies, and especially the repeatability, remain a major challenge.

[0005] In this context, particular reference is made to EP 0 132 878 B1. This patent discloses a method and apparatus for manufacturing nozzle plates for inkjet printers. In this process, a plate, together with a harder metal foil, is stretched through a die opening and punched in a cutting pad. The metal foil acts as an additional die, compacting the material and enabling sharp-edged, smooth, and symmetrical nozzle edges. The use of amorphous or microcrystalline foils with high hardness significantly improves the precision of the nozzles.

[0006] EP 0 064 263 B1 discloses a tool for producing countersunk holes in sheet metal on NC punching machines. The embossing die is guided tightly in the blank holder via a shank section, preventing the material from bulging during embossing. An upwardly curved die simultaneously ensures the parallelism of the top and bottom surfaces of the sheet metal. This allows even closely spaced countersunk holes to be produced precisely, evenly, and without surface deformation. Task

[0007] The object of the present invention is to provide a method of the above type with which such reference nozzles can be manufactured with extreme accuracy and, in particular, with high repeatability. Solution to the task

[0008] The following steps will lead to the solution of the task: - An approximately cylindrical passage is formed into or out of the nozzle body. - A pin is inserted into the opening, which at least partially conforms to the inner contour of the desired opening. - The pin is pressed into the nozzle body in such a way that material of the nozzle body surrounds the pin, thus forming the desired passage with the desired inner contour.

[0009] In practice, this method has proven to produce a very precise reference nozzle with high repeatability. The work steps are simple and very cost-effective.

[0010] In a preferred embodiment of the method, the passage has a larger diameter than the desired opening. In practice, this means that the pin can be easily inserted into the passage, but that raised sections on the pin then displace material from the nozzle body, allowing it to wrap around the pin. This creates the desired opening.

[0011] In a simple embodiment, the pin has a cylindrical front section to which a funnel-shaped rear section is attached.

[0012] If this pin is pressed into a passage with a larger diameter than the desired opening, the funnel-shaped section displaces material from the nozzle body towards the cylindrical section, causing material from the nozzle body to wrap around the cylindrical section and thus form the cylindrical outlet. To ensure that the material flows, a highly ductile material is preferably used for the nozzle body.

[0013] An inventive device for producing a corresponding reference nozzle provides a device for forming a passage into the nozzle body, followed by an embossing die with a pin which has the desired inner contour for the desired passage.

[0014] Protection is also granted for the embossing die for carrying out the inventive method alone, wherein a pin is assigned to a holder which has the desired inner contour for the desired passage. Character description

[0015] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawing; the single figure of the drawing shows a schematic and perspective representation of the inventive method for manufacturing a reference nozzle. This reference nozzle 1 has a nozzle body 2 into which a passage 3 is formed; this passage 2 consists of an approximately cylindrical outlet 4 and a funnel-shaped inlet 5 that expands thereafter.

[0016] In this process, an approximately cylindrical bore 6 is provided in a nozzle body 2.2, preferably having a larger diameter than the approximately cylindrical outlet 4 of the subsequent reference nozzle 1. A pin 7 of a stamping die 8 is then inserted into this cylindrical bore 6, the pin 7 being arranged on a holder 9. This pin 7 also has a cylindrical section 10 and a funnel-shaped section 11, the contours of which correspond to the inlet 5 and outlet 4 of the final reference nozzle 1, respectively.

[0017] The functioning of the present invention is as follows: In a first step, the cylindrical bore 6 with a larger diameter than the subsequently produced outlet 4 is introduced into the nozzle body 2.2.

[0018] In a second step, the pin 7 is inserted into the cylindrical bore 6 and pressure is applied to the stamping die 8, causing the funnel-shaped section 11 to press into the material of the nozzle body 2.2 and the displaced material to flow around the cylindrical section 10. In this way, the opening 3 is created.

[0019] To make the whole process even easier, a ductile material is used as the material for the nozzle body 2.2, i.e., a material that is very suitable for embossing because it is flowable. Reference symbol list 1 Reference nozzle 2 nozzle bodies 3 passages 4 outlets 5 Admission 6 cylindrical bore 7 pen 8 embossing dies 9 bracket 10 cylindrical section 11 funnel-shaped section

Claims

[1] Method for manufacturing a reference nozzle (1) in a device for pneumatic measurement technology, which has a passage (3) with an inner contour (4, 5) in a nozzle body (2), characterized by the following steps: • A cylindrical passage (6) is formed in or out of the nozzle body (2). • A pin (7) is inserted into the passage (6) which at least partially has the inner contour (4, 5) of the desired opening (3). • The pin (7) is pressed into the nozzle body (2.2) in such a way that material of the nozzle body (2.2) surrounds the pin (7) and thus the desired passage (3) with the desired inner contour (4, 5) is formed. [2] Method according to claim 1, characterized by , that the passage (6) is formed with a larger diameter than the desired passage (3). [3] Method according to claim 1 or 2, characterized by, that the passage (6) is produced in an approximately cylindrical shape, for example by drilling. [4] Method according to at least one of the preceding claims, characterized by , that a passage (3) is formed with an approximately funnel-shaped inlet (5) and an approximately cylindrical outlet (4) adjoining it. [5] Device for producing a reference nozzle (1) in a device for pneumatic measurement technology, which has a passage (3) with an inner contour (4, 5) in a nozzle body (2), characterized by , that a device for forming a passage (6) into the nozzle body (2.2) is followed by an embossing die (8) with a pin (7) which has the desired inner contour (4, 5) for the desired passage (3). [6] Stamping die for carrying out the method according to at least one of claims 1 to 4, characterized by, that a holder is associated with a pin (7) which has an outer contour corresponding to a desired inner contour (4, 5) for the desired passage (3).

Images