Nozzle for discharging compressed air

Abstract

The present disclosure relates to a nozzle for discharging compressed air having a circumferential surface section which extends from a feed end to a discharge end and extends at least partially axially, and an end section produced in one piece, which extends radially inward from the circumferential surface section at the discharge end. In order to allow efficient and targeted compressed air discharge, the present disclosure envisages that a plurality of helical passages extend through the end section, each of which slopes in a tangential direction, at least in some section or sections, and into each of which a first discharge opening for compressed air opens.

Claims

1. A nozzle for discharging compressed air comprising: a circumferential surface section extending at least partially axially from a feed end to a discharge end; and an end section extending radially inward from the circumferential surface section at the discharge end, wherein a plurality of helical passages extend through the end section and at least one each helical passage slopes in a tangential direction, wherein each helical passage forms a first discharge opening for compressed air and the end section is adjoined in a direction toward the feed end by a guide passage for guiding compressed air, the guide passage extending tangentially within the circumferential surface section.

2. The nozzle as claimed in claim 1, wherein the end section is one piece.

3. The nozzle as claimed in claim 1, wherein the plurality of helical passages are arranged offset tangentially relative to one another.

4. The nozzle as claimed in claim 1, wherein the end section includes a plurality of axial passages offset tangentially relative to one another radially outside of the plurality helical passages, wherein each axial passage opens into a respective second discharge opening for compressed air.

5. The nozzle as claimed in claim 1, wherein the end section is closed radially on an inside of the plurality of helical passages.

6. The nozzle as claimed in claim 1, wherein an axially extending central section connected to the end section is formed radially inside the guide passage.

7. The nozzle as claimed in claim 1, wherein the first discharge opening of each helical passage is arranged radially outside of an axially extending projection of the end section.

8. The nozzle as claimed in claim 7, wherein each helical passage merges into a helically extending depression on an outer side of the projection.

9. The nozzle as claimed in claim 1, wherein the circumferential surface section includes a plurality of axially extending grooves on an inside region of a guide passage.

10. The nozzle as claimed in claim 9, wherein a rib that projects radially inward along an axial direction is formed between two grooves.

11. A nozzle comprising: a circumferential surface section extending between a feed end to a discharge end; an end section extending radially inward from the circumferential surface section at the discharge end and having a closed central region; a plurality of helical passages extending through the end section and arranged symmetrically around the closed central region of the end section, each helical passage forming a first discharge opening and sloping in a tangential direction; and a plurality of axial passages extending through the end section, each axial passage forming a second discharge opening.

12. The nozzle as claimed in claim 11, wherein a portion of the circumferential surface section defines an external hexagon geometry.

13. The nozzle as claimed in claim 11 further comprising a guide passage having a central section extending along a length of the circumferential surface section, wherein the central section merges with the end section.

14. The nozzle as claimed in claim 13, wherein a region where the central section merges with the end section widens such that a truncated cone is formed.

15. The nozzle as claimed in claim 11 further comprising a guide passage and at least one pair of axially extending grooves extending along an inside region of the circumferential surface section.

16. The nozzle as claimed in claim 15, wherein an axially extending rib is formed between each pair of axially extending grooves, each rib convexly arching inward.

17. The nozzle as claimed in claim 11, wherein the first discharge opening of each helical passage is arranged radially outside of an axially extending projection arranged in the closed central region of the end section.

18. The nozzle as claimed in claim 17, wherein each helical passage merges into a helically extending depression formed on the projection.

19. The nozzle as claimed in claim 11, wherein the second discharge opening of each axial passage is circular or elliptical and merges into an annular depression.

Description

DRAWINGS

(1) In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

(2) FIG. 1 shows a perspective cross-sectional view of a nozzle according to the present disclosure;

(3) FIG. 2 shows a perspective illustration of a part of the nozzle from FIG. 1;

(4) FIG. 3 shows a perspective illustration of a compressed air distributor having a plurality of nozzles in accordance with FIG. 1; and

(5) FIG. 4 shows a perspective illustration of a device having two compressed air distributors in accordance with FIG. 3.

(6) The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

(7) The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

(8) FIGS. 1 and 2 show a nozzle 1 according to the present disclosure for blowing out compressed air, wherein FIG. 1 shows a perspective cross-sectional view of the entire nozzle 1 and FIG. 2 shows a perspective illustration of part of the nozzle 1. The nozzle 1 shown is composed completely of metal and is produced in one piece by selective laser melting (SLM). The nozzle 1 has a circumferential surface section 2 roughly in the form of the circumferential surface of a cylinder, which is formed symmetrically in relation to a central axis A. The central axis A is used to define an axial, a radial and a tangential direction. The circumferential surface section 2 extends axially from a feed end 1.1 of the nozzle 1 to a discharge end 1.2. At the feed end 1.1, the nozzle can be connected to a compressed air feed, for which purpose the circumferential surface section 2 can have an external thread (not shown here), and the compressed air can be expelled at the discharge end 1.2. An external hexagon 2.3, which is provided for engagement with a wrench, is formed on an outer side of the circumferential surface section 2.

(9) At the discharge end 1.2, as it were on the end of the circumferential surface section 2, an end section 3 extends radially inward. Together with the end section 3, the circumferential surface section 2 very largely surrounds a guide passage 10, through which the compressed air is passed from the feed end 1.1 to the end section 3. A series of passages 4, 7 for the targeted discharge of the compressed air is formed within the end section. A plurality of helical passages 4 is arranged symmetrically around the central axis A. In the present case, there are eight helical passages, although this should be taken only as an example. Each helical passage 4 extends in the axial direction through the end section 3, namely from a first inlet opening 5, which adjoins the guide passage 10, to a first discharge opening 6 on the outside of the end section 3. Here, the course of each helical passage 4 is in the form of a helix or helical line, which implies that it does not extend axially but slopes in the tangential direction. The helical passages 4 and thus also the first discharge openings 6 are arranged at the same radial distance from the central axis A and are each offset tangentially relative to one another by the same angle (namely 40). To reduce the air friction within the helical passages 4, they have a circular (or slightly elliptical) cross section.

(10) Radially on the inside of the helical passages 4, the end section is of closed design and has a conical axial projection 3.2. This serves to guide the air flows emerging from the helical passages 4 and keeps them separate from one another immediately after emergence. In this case, helically extending depressions 3.3 are formed on the outside of the projection 3.2. Each helical passage 4 merges into one of the eight depressions 3.3, so that each depression 3.3 guides the emerging air flow, as it were supplementing the action of the helical passage 4.

(11) Formed radially on the outside of the helical passages 4 is a plurality of axial passages 7, which extend axially through the end section 3. In this case, each axial passage 7 extends from a second inlet opening 8 to a second discharge opening 9. Here, the second discharge openings 9 are arranged within an annular depression 3.1 in the end section 3. In contrast to the helical passages 4, the axial passages 7 do not slope in a tangential direction. In the present case, fifteen axial passages 7 are provided, although this should be understood only by way of example. In this arrangement, the cross section of the axial passages 7 is circular or slightly elliptical.

(12) Radially on the inside of the first inlet opening 5, the end section 3 merges into a central section 11 within the guide passage 10. In this case, the central section 11 is of circular-symmetrical and column-type design and extends in a self-supporting manner along the entire length of the circumferential surface section 2. In the region of transition to the end section 3, the central section 11 is widened in the manner of a truncated cone. The function of the central section is essentially to guide the air flow on the way from the feed end 1.1 to the end section 3 away from the central axis A and thus approximately toward the first and second inlet openings 5, 8. Likewise serving to guide the air flow within the guide passage 10 is a plurality of axially extending grooves 2.1, which extend along the inside of the circumferential surface section 2 to just before the end section 3. An axially extending rib 2.2 is formed between each pair of grooves 2.1. Along the axial direction, each rib 2.2 arches convexly inward. In the present case, each groove 2.1 is in alignment with an axial passage 7, thereby assisting division and guidance of components of the air flow toward the axial passages 7.

(13) During operation, the nozzle 1 is connected to a compressed air feed, resulting in an air flow through the guide passage 10, the helical passages 4 and the axial passages 7. While the air flow emerges substantially in an axial direction from the second discharge openings 9 of the axial passages 7, the air flow emerges from the first discharge openings 6 of the helical passages 4 with a tangential velocity component, resulting in an air flow resembling a helical line in interaction with the helical passages 4. This air flow interacts with the air flow emerging from the axial passages 7, which can contribute to constriction or focusing of the air flow. Overall, it has been found that the air flow is constricted radially with increasing distance from the end section 3, that is to say is as it were focused, wherein the speed thereof increases. Relatively high speeds can therefore be achieved at a certain distance from the nozzle 1, even if the air pressure at the feed end 1.1 is only moderate. At the same time, the movement resembling a helical line within the air flow provides turbulence, which, in interaction with the high speed of flow, provides that the air flow is well-suited to cooling an object.

(14) An illustrative use of the nozzle 1 is illustrated in FIGS. 3 and 4. In this case, FIG. 3 shows a compressed air distributor 21, having four discharge connections 21.1, to each of which a nozzle 1 is connected. At the side, the compressed air distributor 21 has a feed connection 21.2, which is connected to a compressed air source. As illustrated in FIG. 4, two such compressed air distributors 21 can be used as parts of a device 20 for the primary forming of a component. The exact construction of the device 20 is not relevant here and, to this extent, is not explained in detail. Inter alia, it has two mold halves 22, 23, which each have a frame and an insert inserted therein. Here, the frame is cast from synthetic resin and the insert is produced from plastic in a 3-D printing process. Since both said materials have relatively poor thermal conductivity, liquid cooling of the mold halves 22, 23 would not be effective. Instead, a cooling air flow is directed at the mold halves 22, 23 by means of the compressed air distributors 21 and of the nozzles 1 according to the present disclosure (not shown in FIG. 4), the air flow being distinguished by good heat transfer and thus a good cooling effect, even at a relatively low air pressure, by virtue of the flow profile described above.

(15) The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.