Blowing-out device, system and method for operating the blowing-out device

The purging device with oblique channel and injection zones forms protective gas cushions to prevent particle accumulation on sensor housings, enhancing sensor reliability and reducing cleaning needs in particle-laden environments.

WO2025163116A1PCT designated stage Publication Date: 2025-08-07PRIMETALS TECH AUSTRIA GMBH
View PDF 8 Cites 0 Cited by

Patent Information

Application Number
PCT/EP2025/052480
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-02-02
Filing Date
2025-01-31
Publication Date
2025-08-07

AI Technical Summary

Technical Problem

Existing purging devices for protecting sensor housings in particle- and vapor-laden environments are ineffective in preventing particle accumulation on protective glass, leading to frequent cleaning needs and reduced system reliability.

Method used

A purging device with a flow distributor and nozzle arrangements that create obliquely inclined channels and injection zones to form protective gas cushions, preventing particle entry and ensuring a stable flow that maintains a clean environment around the sensor housing.

Benefits of technology

The design effectively prevents particle accumulation on the protective glass, ensuring reliable long-term operation of the sensor by maintaining a clean environment and reducing the need for frequent cleaning.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure EP2025052480_07082025_PF_FP_ABST
    Figure EP2025052480_07082025_PF_FP_ABST
Patent Text Reader

Abstract

The invention relates to a blowing-out device (20), to a system (10), and to a method for operating the blowing-out device (20), wherein the blowing-out device (20) has at least one flow distributor (90), a housing opening (95) and a blow-out opening (100), wherein the blowing-out device (20) extends along an axis (55) between the housing opening (95) and the blow-out opening (100) which is opposite the housing opening (95), wherein between the housing opening (95) and the blow-out opening (100), the blowing-out device (20) encloses a protective space (135), wherein a sensor device (25) can be positioned at the housing opening (95) and the blow-out opening (100) can face the dust-laden environment (60), wherein the flow distributor (90) has at least a first nozzle arrangement (140) with at least a first passage opening (155), a first inner wall (105) and a first channel arrangement (170) with at least a first connecting channel (185), wherein the first inner wall (105) extends from the housing opening (95) towards the blow-out opening (100) and circumferentially encloses the protective space (135) at least in certain portions, wherein the first nozzle arrangement (140) is spaced apart from the housing opening (95) on the first inner wall (105), wherein a first channel portion (190) of the first connecting channel (185) opens at the first passage opening (155) and has an obliquely inclined orientation with respect to the axis (55), wherein a pressurized protective gas (65) can be conducted via the first connecting channel (185) to the first passage opening (155) and from the first passage opening (155) into the protective space (135).
Need to check novelty before this filing date? Find Prior Art

Description

[0001] Description

[0002] Purging device, system and method for operating the purging device

[0003] The invention relates to a purging device according to patent claim 1, a system according to patent claim 13 and a method for operating the purging device according to patent claim 14.

[0004] EP 0 547 227 A1 discloses a device for optically inspecting the surface of a roller. Compressed air is directed parallel to a protective glass of a housing to prevent contamination of the protective glass. Compressed air is applied to the glass plate from both sides, from above and below, which allows dirt particles from the surrounding area to accumulate in the area where the two compressed air streams meet.

[0005] From KR 2016 0078788 A, a purging device is known which is arranged in front of a camera's viewing window and has a viewing channel for the camera and at least two injection zones that enclose the viewing channel. In a first injection zone, air is injected into the viewing channel perpendicular to the viewing window. In a second injection zone, which is arranged behind the first injection zone from the camera's perspective, air is injected into the viewing channel in a direction away from the viewing window. A conically tapered air guiding device is arranged behind the second or last injection zone.

[0006] DE 10 2019 214 705 A1 discloses a cleaning device for a protective glass arranged in front of a vehicle camera. A fluid cleaning agent is applied tangentially to the protective glass via one or more spray nozzles. Furthermore, the cleaning device can have one or more blower nozzles for blowing an air stream toward the protective glass.

[0007] DE 10 2019 101 092 A1 teaches a cleaning device for a camera, wherein the cleaning device is arranged as an annular attachment in front of an optical surface of the camera. The cleaning device has an annular distribution channel to which cleaning fluid or compressed air is supplied from the outside. Via a plurality of further channels that branch off from the inside of the distribution channel and are inclined both in the direction of the optical surface of the camera and have a tangential directional component, cleaning fluid or compressed air is applied to the optical surface, forming a swirl. For a vehicle camera, a cleaning device is known from EP 3 006 278 A1, which is arranged as an annular attachment in front of the optics of the vehicle camera and is designed to dispense a gaseous or liquid cleaning fluid onto the optics.The cleaning fluid is fed into an annular distribution channel of the cleaning device and is then discharged onto the optics via a plurality of bores arranged on the inside of the annular attachment and aligned in the direction of the optics.

[0008] WO 2005 / 102544 A1 describes, as prior art, a blow-out device for a protective housing (Fig. 5), in the interior of which a camera is arranged and which is closed off at the front by means of a transparent viewing window for the camera. On the outside of the front of the protective housing, an outflow unit with a first and a further wall section is arranged. The first, conically widening wall section has an outlet for discharging air. Between the first wall section and the viewing window, a further wall section is arranged which is oriented normal to the viewing window and also has an air outlet by means of which the viewing window is supplied with air tangentially.

[0009] It is an object of the invention to provide an improved purging device for a system, an improved system and an improved method for operating the system.

[0010] This object is achieved by means of a purging device according to claim 1, a system according to claim 10, and a method according to claim 11. Advantageous embodiments are specified in the dependent claims.

[0011] It has been recognized that an improved purging device can be provided in that the purging device has at least one flow distributor, a housing opening and a blow-out opening. The purging device extends along an axis between the housing opening and the blow-out opening arranged opposite the housing opening. The purging device encloses a protective space between the housing opening and the blow-out opening. A sensor device can be arranged at the housing opening, and the blow-out opening can be turned towards the dust-laden environment. The flow distributor has at least a first nozzle arrangement with at least one first passage opening, a first inner wall and a first channel arrangement with at least one first connecting channel. The first inner wall extends from the housing opening in the direction of the blow-out opening and encloses the protective space at least in sections on the circumference.The first nozzle arrangement is arranged at a distance from the housing opening on the first inner wall, with the first connecting channel opening with a first channel section at the first passage opening, which is oriented at an angle to the axis. A pressurized shielding gas can be guided to the first passage opening via the first connecting channel and from the first passage opening into the protective chamber.

[0012] This design has the advantage that the obliquely inclined orientation of the first channel section of the first connecting channel creates a protective gas cushion in front of the housing opening, preventing the accumulation of particles or the transport of particles toward the housing opening. This effectively prevents the accumulation of particles in the area of ​​the housing opening, for example, on a protective glass of a sensor housing, thus enabling a long operating time of the system until the next cleaning.

[0013] Furthermore, the first nozzle arrangement has a plurality of first passage openings, preferably at least 10 to 25 inclusive, in particular at least 15 to 25 inclusive, arranged circumferentially around the axis at a distance from one another. Each of the first passage openings is fluidically connected to a respective associated first channel section of the first connecting channel, wherein each of the first channel sections is arranged obliquely to the axis at a respective first channel angle. By means of the oblique arrangement of the plurality of passage openings and first channel sections of the respective first connecting channel, a first injection zone can be created in the protective space during operation of the purging device. The first injection zone can essentially completely enclose the protective gas cushion on the circumferential side and achieve an essentially stationary flow in the protective gas cushion in front of the housing opening.

[0014] In addition, the flow distributor has a second nozzle arrangement with at least one second passage opening and a second channel arrangement with at least one second connecting channel. The second nozzle arrangement is arranged offset from the first nozzle arrangement in the axial direction with respect to the axis. Each second connecting channel has a second channel section, wherein the second channel section opens at the second passage opening and is aligned at a second channel angle inclined to the axis adjacent to the second passage opening. The second channel angle is different, in particular smaller, than the first channel angle. This configuration has the advantage that the second nozzle arrangement can create a second injection zone which circumferentially encloses the first injection zone and has a different alignment to the first injection zone.In particular, the second injection zone can be designed to be wider than the first injection zone. This additionally protects the housing opening from further particle entry through the second nozzle arrangement.

[0015] Furthermore, the second nozzle arrangement has a plurality of second passage openings, preferably at least 10 to 25, in particular at least 15 to 25, arranged circumferentially spaced from one another around the axis. Each of the second passage openings is fluidically connected to a respective associated second channel section of the second connecting channel. The plurality of second passage openings ensures that the second injection zone, which protects the first injection zone, is formed in a manner that completely encloses the second injection zone in the circumferential direction.

[0016] In a further embodiment, the purging device has an outflow unit. The first inner wall of the flow distributor is widened from the housing opening towards the blow-out opening. The outflow unit is arranged on a side of the flow distributor facing away from the housing opening and adjoins the blow-out opening radially on the outside. The outflow unit encloses the protective space on the circumference with a second inner wall. The second inner wall is tapered from the flow distributor towards the blow-out opening. This configuration has the advantage that the protective gas flows through the second inner wall and backflow, in particular of particles from the environment, via the blow-out opening towards the housing opening along the second inner wall is avoided.Furthermore, this ensures that a narrow backflow path, along which the particles could flow back toward the housing opening, is avoided, and that the particles remain well spaced from the housing opening. Furthermore, the tapered design of the discharge unit, in particular, ensures that the flow velocity of the shielding gas increases from the second inner wall toward the axis, and that particles are blown away from the discharge opening by the shielding gas flowing through the discharge opening.

[0017] In a further embodiment, the second inner wall adjacent to the flow distributor has a first maximum extension perpendicular to the axis. In the axial direction relative to the axis, the second inner wall has a first height between the exhaust opening and adjacent to the flow distributor. A first ratio of the first height to the first maximum extension is 0.5 to 2 inclusive. This configuration ensures that the housing opening is arranged at a large spatial distance from the exhaust opening and the particle-laden environment.

[0018] In a further embodiment, the second inner wall adjacent to the flow distributor has a first maximum extension perpendicular to the axis. The second inner wall has a second maximum extension perpendicular to the axis at the blow-out opening. A second ratio of the second maximum extension to the first maximum extension is 0.5 to 0.8 inclusive, in particular 0.55 to 0.7 inclusive. This configuration has the advantage that the tapered configuration can provide a nozzle-like configuration of the blow-out device, in particular of the outflow unit, in which the flow of the protective gas is accelerated from the housing opening towards the blow-out opening.

[0019] In a further embodiment, the purging device has a first distribution chamber, wherein the first channel arrangement with the first connecting channel opens into the first distribution chamber on a side facing away from the first passage opening. The protective gas can be guided to the first connecting channel via the first distribution chamber. It is particularly advantageous if the first distribution chamber has a significantly larger volume than the combined volume of the connecting channels. The first distribution chamber serves, for example, as a buffer storage for the protective gas and equalizes the protective gas flowing into the first distribution chamber.

[0020] In a further embodiment, the first passage opening has a first exit area, wherein the first channel section has a first channel cross-sectional area at a distance from the first passage opening. The second passage opening has a second exit area, wherein the second channel section has a second channel cross-sectional area at a distance from the second passage opening. A third ratio of a first total cross-sectional area formed from a first sum of the first and second exit areas to a second total cross-sectional area formed from a second sum of the first and second channel cross-sectional areas is 0.1 to 0.6 inclusive, in particular 0.2 to 0.5 inclusive.This design has the advantage that the passage openings each serve as a flow resistance for the shielding gas, and as a result, the velocity of the shielding gas at the passage opening is particularly high. This results in the first and / or second injection zone in particular being formed stably in the protective space. In a further embodiment, the first passage opening in each case has a first outlet area, wherein the second passage opening in each case has a second outlet area. A fourth ratio of a third total cross-sectional area formed from a third sum of the first outlet areas to a fourth total cross-sectional area formed from a fourth sum of all outlet areas of the passage openings is 0.2 up to and including 0.5, in particular 0.25 up to and including 0.45. This ensures uniform filling of the protective space.

[0021] In a further embodiment, the first inner wall has a first wall section, wherein the first wall section is conical. The first wall section forms a first wall angle with the axis. The first wall angle is preferably 40° to 70° inclusive. It is particularly advantageous if the first channel section of the first connecting channel is preferably oriented substantially perpendicular to the first wall angle. The conical configuration of the first wall section further supports the formation of the first injection zone.

[0022] In a further embodiment, the first inner wall has a second wall section, wherein the second wall section is conically shaped. The second wall section encloses a second wall angle with the axis. The second wall angle is greater than the first wall angle and less than 90°. In this case, the second wall section preferably adjoins the first wall section radially on the outside. The design of the second wall section with a larger second wall angle than the first wall angle results in the flow distributor being stepped on the first inner wall and requiring only a small axial extension until it extends to the blow-out unit. This ensures a short axial design of the blow-out device.Furthermore, the formation of the second injection zone can be ensured in a simple manner, in particular with a substantially perpendicular alignment of the second channel section of the second connecting channel to the second wall section.

[0023] An improved system can be provided in that the system comprises a sensor device, a protective gas device, and a purging device. The purging device is designed as described above. The sensor device comprises a sensor, a sensor housing, and a protective glass, wherein the sensor housing encloses a housing interior in which the sensor is arranged. The protective glass is arranged at the housing opening and closes the housing interior. The protective gas device is designed to provide a purified and / or pressurized protective gas. The protective gas device is further fluidically connected to the purging device.

[0024] The purified protective gas, which is blown into the protective chamber via the purge device on the protective glass, can prevent the accumulation of particles on the protective glass, thus ensuring good recording of the sensor through the protective glass on a large-scale industrial plant.

[0025] An improved method for operating the purging device described above can be provided in that a pressurized protective gas is fed to the first nozzle arrangement via the first connecting channel. The protective gas is directed through the first channel section and directed via the first passage opening into the protective chamber. The protective gas flows in the direction of the blow-out opening in the protective chamber and forms a protective gas cushion at the housing opening. The protective gas exits the protective chamber at the outlet opening. The protective gas preferably carries particles entering via the blow-out opening out of the protective chamber and / or reduces the entry of particles into the protective chamber via the blow-out opening. This effectively prevents particles from adhering to the housing opening, in particular to the protective glass of the sensor device.It is particularly advantageous if the shielding gas flows laminarly with a Reynolds number of less than 16,000 in the protective chamber from the first nozzle arrangement toward the exhaust opening. Preferably, a relative volume of essentially 0.04 l / min / mm² relative to the cross-sectional area of ​​the exhaust opening is achieved. 2 up to 0.4 l / min / mm 2 of shielding gas into the protective chamber. Furthermore, it is additionally or alternatively advantageous if the shielding gas is supplied at an overpressure relative to the ambient pressure of 0.5 bar up to and including 1.5 bar, in particular 0.7 bar up to and including 1.0 bar.

[0026] The invention is explained in more detail below with reference to the figures. These show:

[0027] FIG 1 shows a schematic sectional view through a system according to a first embodiment for a large-scale industrial plant;

[0028] FIG. 2 shows a section A of the purge device shown in FIG. 1, marked in FIG. 1; FIG. 3 shows a plan view of the flow distributor from the discharge opening;

[0029] FIG 4 is a sectional view of the system shown in FIG 1;

[0030] FIG 5 is a sectional view of section A marked in FIG 1 of the blow-out device shown in FIG 1;

[0031] FIG 6 is a schematic representation of the outflow unit and the flow distributor of the system shown in FIGS 1 to 5;

[0032] FIG 7 is a perspective view of a system according to a second embodiment;

[0033] FIG 8 is a perspective view of the system shown in FIG. 7 according to the second embodiment;

[0034] FIG 9 the system shown in FIGS 7 and 8, whereby in Fig. 9 the illustration of the blow-out device is omitted;

[0035] FIG 10 is a sectional view along a section plane BB shown in FIG 7 through the system shown in FIG 7;

[0036] FIG 11 is a perspective view of a system according to a third embodiment;

[0037] FIG 12 shows a semi-longitudinal section through a system according to a third embodiment;

[0038] FIG 13 is a sectional view through the system taken along a sectional plane CC shown in FIG 12;

[0039] FIG 14 is a sectional view along the section plane EE shown in FIG 11 through the camera system; and

[0040] FIG. 15 shows a sectional view along a sectional plane DD shown in FIG. 12 through the system shown in FIG. 12; and FIG. 16 shows a schematic sectional view through a system according to a fourth embodiment for a large-scale industrial plant.

[0041] FIG 1 shows a schematic sectional view through a system 10 according to a first embodiment for a large-scale industrial plant.

[0042] A large-scale industrial plant could be, for example, a rolling mill, a melting facility such as an electric arc furnace or smelter, a combined casting and rolling plant, or a continuous casting machine. Of course, other large-scale industrial plants are also possible.

[0043] Within the large-scale industrial plant, a large number of particles and / or vapor are emitted into their surroundings 60 during the manufacture of products, for example, metallic foundry products such as slabs or billets, or rolled products such as sheet metal. Within the scope of monitoring the respective manufacturing process and / or the large-scale industrial plant, the system 10 described below is used according to the respective embodiment.

[0044] The system 10 comprises a protective gas device 15, a purge device 20, and a sensor device 25. The sensor device 25 comprises at least one sensor 30, a power supply 35, a sensor housing 40, and a protective glass 45. The sensor can be, for example, an optical sensor, an image sensor, such as a CCD sensor or a CMOS sensor. Furthermore, the sensor is designed to detect electromagnetic radiation with a wavelength of 350 nm to 900 nm, in particular from the UV and / or IR ranges.

[0045] The sensor housing 40 encloses a housing interior 50, wherein the sensor 30 and the power supply 35 are arranged in the housing interior 50. The sensor housing 40 has, for example, a substantially cylindrical basic shape and extends along an axis 55. The protective glass 45 is arranged on a first end face of the sensor housing 40 and closes off the housing interior 50 at the end. The protective glass 45 is transparent to electromagnetic radiation, in particular light radiation. In the axial direction relative to the axis 55, the sensor 30 is arranged, for example, offset from the protective glass 45. The sensor 30 is directed towards the protective glass 45 in order to record images of the large-scale industrial plant through the protective glass 45. The protective glass 45 closes off the housing interior 50 on the side facing the large-scale industrial plant and prevents penetration oran air exchange with the particle- and / or vapor-laden environment 60 and thus a contamination of the components arranged in the housing interior 50, in particular the power supply unit 35 and the sensor 30.

[0046] The power supply 35 is designed to supply the sensor 30 with electrical energy from a power grid. For example, the power supply 35 is arranged in the housing interior 50, axially opposite the protective glass 45, and is electrically connected to the sensor housing 40.

[0047] The purging device 20 is arranged on the sensor housing 40, axially adjacent to the sensor housing 40, on an axial side facing the protective glass 45. The purging device 20 is designed to protect the protective glass 45 from contamination with particles in the particle- and / or vapor-laden environment 60. The detailed design of the purging device 20 is discussed in the following figures. In a first embodiment, the purging device 20 can be formed together with the sensor housing 40, or, as an optional add-on part according to a second embodiment, can be additionally and / or subsequently mounted on the sensor housing 40.

[0048] During operation of the system 10 in the particle- and / or vapor-laden environment 60, the purge device 20 is supplied with a pressurized protective gas 65 by the protective gas device 15. The protective gas 65 is preferably purified and has a reduced number of particles compared to the particle- and / or vapor-laden environment 60. The protective gas 65 may comprise air.

[0049] The sensor housing 40 has a first housing part 70, a housing cover 75, and, for example, a second housing part 80. The first and / or second housing part 70, 80 can, for example, be designed like a hollow body, in particular a hollow cylinder. The first and second housing parts 70, 80 each extend along the axis 55. The first housing part 70 and the second housing part 80 are arranged axially adjacent to one another and, for example, connected to one another. The protective glass 45 is fastened to the second housing part 80 on an end face facing away from the first housing part 70. The housing cover 75 is arranged on an end face of the sensor housing 40 opposite the protective glass 45 and closes the housing interior 50 opposite the protective glass 45.

[0050] A shielding gas connection 85 can be arranged on the first housing part 70, which, for example, opens into the housing interior 50. The shielding gas device 15 is fluidically connected to the shielding gas connection 85, and the shielding gas 65 can be guided into the sensor device 25 via the shielding gas connection 85. The shielding gas connection 85 can be arranged, for example, on a side of the sensor housing 40 axially facing the housing cover 75.

[0051] On the side axially opposite to the housing cover 75, the blow-out device 20 is connected to the second housing part 80.

[0052] The purging device 20 has at least one flow distributor 90, a housing opening 95, and a blow-out opening 100. The purging device 20 extends along the axis 55, with the housing opening 95 being arranged on the side axially facing the sensor device 25. In particular, the housing opening 95 axially adjoins the protective glass 45. The blow-out opening 100 is arranged axially opposite the housing opening 95 with respect to the axis 55. The blow-out opening 100 opens into the particle- and / or vapor-laden environment 60 and can, for example, be directed toward the large-scale industrial plant.

[0053] During operation, the sensor 30 captures images and is directed toward the large-scale industrial plant via the protective glass 45, the housing opening 95, and the exhaust opening 100. The purge device 20 protects the protective glass 45 from contamination with particles from the particle- and / or vapor-laden environment 60 by means of the pressurized protective gas 65, thus enabling reliable, long-term images of the large-scale industrial plant with the sensor 30. Furthermore, vapor condensation on the cool protective glass 45 is prevented.

[0054] FIG 2 shows a section A marked in FIG 1 of the purging device 20 shown in FIG 1.

[0055] The housing opening 95 is circumferentially enclosed by the flow distributor 90 and can, for example, have a circular profile. Adjacent to the housing opening 95, the flow distributor 90 has a first inner wall 105, which widens with increasing distance from the housing opening 95 toward the exhaust opening 100. The first inner wall 105 can have a stepped conical basic shape.

[0056] The first inner wall 105 can, for example, have a first wall section 110, wherein the first wall section 110 is, for example, conical. The first wall section 110 can be formed at a first wall angle α to the axis 55. The first wall angle α can have a value of 40° to 70° inclusive.

[0057] In addition, the flow distributor 90 can have a second wall section 115 on the first inner wall 105, wherein the second wall section 115 adjoins the first wall section 110 radially on the outside and also in the axial direction with respect to the axis 55. The second wall section 115 is, for example, conical in design, wherein with increasing distance on the second wall section 115, starting from the housing opening 95 towards the blow-out opening 100, the flow distributor 90 widens at the second wall section 115. The second wall section 115 can enclose a second wall angle β with the axis 55, wherein the second wall angle β is greater than the first wall angle α. The second wall angle β can have a value of 55° up to and including 85°, and in any case greater than α.

[0058] In addition to the first and second wall sections 110, 115, the flow distributor 90 can have a third wall section 120 on the first inner wall 105. The third wall section 120 adjoins the second wall section 115 radially outward and in the axial direction on a side facing away from the first wall section 110. The third wall section 120 can, for example, be conical or perpendicular to the axis 55. In this case, the third wall section 120 encloses a third wall angle y with the axis 55, wherein the third wall angle y is greater than the second wall angle ß and the first wall angle α. The third wall angle y can, for example, be from 65° up to and including 90°, and in any case greater than β.

[0059] Radially outwardly of the third wall section 120, a first outer circumferential side 126 is adjoined, wherein the first outer circumferential side 126 is formed substantially cylindrically around the axis 55.

[0060] The purge device 20 further comprises an outflow unit 125. The outflow unit 125 can be formed integrally and of the same material as the second housing part 80. The outflow unit 125 and the second housing part 80 can also be formed in two or more parts.

[0061] The outflow unit 125 adjoins the flow distributor 90 at least in the axial direction. In addition, as shown in FIG 2, the outflow unit 125 can also enclose the flow distributor 90 on the circumferential side on the first outer circumferential side 126. The outflow unit 125 is designed as a hollow body and preferably as a rotating body about the axis 55. On the circumferential side, for example in the radial direction, the outflow unit 125 delimits the blow-out opening 100. The outflow unit 125 has a second inner wall 130 which, starting from the flow distributor 90, is tapered towards the blow-out opening 100. The second inner wall 130 can, for example, be arranged inclined at a fourth wall angle θ to the axis 55. The fourth wall angle θ can be between 2° and 20° inclusive.

[0062] The second inner wall 130 adjoins the first inner wall 105 axially on the axial side facing the housing opening 95. Together with the first inner wall 105, the second inner wall 130 defines a protective space 135. The protective space 135 further extends in the axial direction between the housing opening 95 and the exhaust opening 100 and is open at the exhaust opening 100.

[0063] The flow distributor 90 has a first nozzle arrangement 140. In addition to the first nozzle arrangement 140, the flow distributor 90 can also have at least one second nozzle arrangement 145 and preferably a third nozzle arrangement 150. The number of nozzle arrangements 140, 145, 150 is freely selectable. However, it is particularly advantageous if at least the first nozzle arrangement 140 and the second nozzle arrangement 145 are provided. The first nozzle arrangement 140 is arranged, for example, on the first wall section 110, the second nozzle arrangement 145 is arranged on the second wall section 115, and the third nozzle arrangement 150 is preferably arranged on the third wall section 120.

[0064] The first nozzle arrangement 140 has at least one, preferably a plurality of first passage openings 155 arranged offset in the circumferential direction around the axis 55. The first passage opening 155 can, for example, have a partially annular profile. If a plurality of first passage openings 155 are provided, the first passage openings 155 can preferably be identical and, for example, arranged at a regular distance from one another in the circumferential direction around the axis 55. Each of the first passage openings 155 has a first exit surface, wherein the first exit surfaces are preferably identical. It is particularly advantageous if at least 10 to 25 first passage openings 155, in particular at least 15 to 25, are provided. The first passage opening 155 is formed, for example, in the first wall section 110.The second nozzle arrangement 145 is arranged radially outwardly of the first nozzle arrangement 140, for example, in the second wall section 115. The second nozzle arrangement 145 has at least one, preferably a plurality of, second passage openings 160. In particular, the second nozzle arrangement 145 has at least 10 to 25, preferably at least 15 to 25, second passage openings 160. For example, the second passage openings 160 are spaced apart in the circumferential direction, preferably regularly, around the axis 55. The second passage opening 160 can, for example, have a partially annular profile and a second exit surface.

[0065] The third nozzle arrangement 150 can, for example, be designed analogously to the first and second nozzle arrangements 140, 145. The third nozzle arrangement 150 has at least one third passage opening 165, wherein the third passage opening 165 has, for example, a partially annular profile and a third exit surface. Preferably, the third nozzle arrangement 150 has a plurality of third passage openings 165 arranged offset in the circumferential direction, preferably at regular intervals. The third nozzle arrangement 150 is arranged, for example, at a radial distance from the second inner wall 130 and from the first outer circumferential side 126.

[0066] Furthermore, the flow distributor 90 has at least one first channel arrangement 170. In addition, the flow distributor 90 can have a second channel arrangement 175 and a third channel arrangement 180. The first channel arrangement 170 has at least one first connecting channel 185, wherein the first connecting channel 185 opens with a first channel section 190 at the first passage opening 155. The first channel section 190 is directly adjacent to the first passage opening 155 and can extend in a straight line adjacent to the first passage opening 155. The first channel section 190 is aligned at a first channel angle aK inclined to the axis 55. The first channel section 190 can, for example, be formed in the manner of a bore adjacent to the first passage opening 155. The first channel section 190 has a first maximum channel cross-sectional area in cross-section spaced from the first passage opening 155.Furthermore, the first channel section 190 is preferably aligned perpendicular to the first wall section 110.

[0067] In the embodiment, a first connecting channel 185 is provided for each first passage opening 155, wherein the first connecting channel 185 opens into the first channel section 190 at the respectively associated first passage opening 155. The shielding gas 65 can be guided to the first passage opening 155 via the first connecting channel 185, wherein an outflow direction of the shielding gas 65 at the first passage opening 155 is structurally determined by an alignment of the first channel section 190.

[0068] Analogous to the first channel arrangement 170, the second channel arrangement 175 has at least one second connecting channel 195, wherein preferably a second connecting channel 195 of the second channel arrangement 175 is provided for each of the second passage openings 160. The second connecting channel 195 opens at the second passage opening 160 with a second channel section 200. With the second channel section 200, which is designed, for example, in the manner of a bore, an outflow direction of the protective gas 65 at the second passage opening 160 can be structurally determined. The second channel section 200 of the second connecting channel 195 can, for example, be designed in the manner of a bore. In this case, the second channel section 200 is aligned at a second channel angle βK to the axis 55. The second channel section 200 has, in cross-section, a second maximum channel cross-sectional area spaced from the second passage opening 160.Furthermore, the second channel section 200 is preferably aligned perpendicular to the second wall section 115.

[0069] The third channel arrangement 180 has at least one third connecting channel 205 with a third channel section 210, wherein the third channel section 210 is arranged adjacent to the third passage opening 165. The third connecting channel 205 opens at the third passage opening 165, wherein a third channel section 210 of the third connecting channel 205 adjoins the third passage opening 165. The third channel section 210 can be shaped like a bore. In this case, the third channel section 210 is inclined at a third channel angle yK or oriented perpendicular to the axis 55. Preferably, the third channel section 210 can be oriented parallel to the second inner wall 130, such that the third channel angle yK substantially corresponds to the fourth wall angle δ. The third channel section 210 has a third maximum channel cross-sectional area in cross-section spaced from the third passage opening 165.Furthermore, the third channel section 210 is preferably aligned perpendicular to the third wall section 120.

[0070] FIG 3 shows a plan view of the flow distributor 90 from the blow-out opening 100.

[0071] The housing opening 95 is centered on the axis 55. The first nozzle arrangement 140 is arranged on a first circular path around the axis 55, wherein, for example, in the radial direction, the first nozzle arrangement 140 is arranged centrally to the maximum extent in the first wall section 110. Radially outward from the first nozzle arrangement 140, on the second wall section 115, the second nozzle arrangement 145 is arranged on a second circular path around the axis 55. In this case, the second nozzle arrangement 145 can be aligned in the radial direction in a central position relative to a maximum extent of the second wall section 115.

[0072] The third nozzle arrangement 150 is arranged radially outwardly of the second nozzle arrangement 145, for example, on a third circular path around the axis 55. In the radial direction, the third nozzle arrangement 150 can be aligned centrally relative to a maximum extension of the third wall section 120.

[0073] It is particularly advantageous if a first ratio of a first total cross-sectional area formed from a first sum of the outlet surfaces to a second total cross-sectional area formed from a second sum of the channel cross-sectional areas is 0.1 to 0.6 inclusive, in particular 0.2 to 0.5 inclusive. In the embodiment, the first sum is formed over all first to third outlet surfaces and the second sum over all first to third channel cross-sectional areas.

[0074] Furthermore, it is advantageous if a second ratio of the third total cross-sectional area formed from the third sum of the first exit areas of the first passage openings to a fourth total cross-sectional area formed from a fourth sum of all exit areas is 0.2 up to and including 0.5, in particular 0.25 up to and including 0.45.

[0075] Furthermore, it is advantageous if a fifth total cross-sectional area formed from a sum of the aperture area of ​​the apertures 215 is larger than the first total cross-sectional area.

[0076] FIG 4 shows a sectional view of the system 10 shown in FIG 1.

[0077] The purging device has a first distribution chamber 211 and a second distribution chamber 220, wherein, for example, due to the integrated design of the purging device 20 and the sensor housing 40, the housing interior 50 is divided into, for example, the first distribution chamber 211 and, for example, the second distribution chamber 220.

[0078] In this case, for example, the first housing part 70 together with the housing cover 75 delimits the second distribution chamber 220 on the side facing away from the protective space 135. The second distribution chamber 220 is arranged on a side facing away from the purging device 20.

[0079] The sensor housing 40 has a flow aperture 212, which is arranged axially spaced from the flow distributor 90 on the side facing the housing cover 75. In the axial direction, for example, the first distribution chamber 211 is arranged between the flow aperture 212 and the flow distributor 90. The first to third channel arrangements 170, 175, 180 open into the first distribution chamber 211, respectively. The first distribution chamber 211 can be annular and extend in the circumferential direction around the axis 55.

[0080] The first distribution chamber 211 is delimited radially outwardly by the second housing part 80. A sleeve 225 extending axially along the axis 55 can be inserted into the second housing part 80 radially inwardly. The sleeve 225, which has a smaller outer diameter than the inner diameter of the second housing part 80, gives the first distribution chamber 211 an annular shape and can also be referred to as an annular chamber. The sleeve 225 is designed, for example, such that it is wider in the radial direction than the housing opening 95 and is thus located outside the detection range of the sensor 30.

[0081] A volume of the first distribution chamber 211 is preferably selected to be larger than a total volume of the connecting channels 185, 195, 205 of the channel arrangements 170, 175, 180. The first distribution chamber 211 is arranged upstream of the respective channel arrangements 170, 175, 180.

[0082] The flow orifice 212 is arranged upstream of the first distribution chamber 211 and the flow distributor 90. The flow orifice 212 can have one or more orifice openings 215, which have a smaller cross-section than the first distribution chamber 211.

[0083] Axially on the side facing the housing cover 75, the sensor housing 40 has the second distribution chamber 220, wherein the second distribution chamber 220 in the embodiment is circumferentially delimited by the first housing part 70, for example.

[0084] For example, the power supply 35 and / or the sensor 30 can be arranged in the second distribution chamber 220. The second distribution chamber 220 can extend in the axial direction relative to the axis 55 between the housing cover 75 and the flow orifice 212. In the embodiment, the sensor 30 is arranged radially inward of the flow orifice 212, for example. Furthermore, the power supply 35 is arranged axially between the sensor 30 and the housing cover 75.

[0085] The protective gas connection 85 is arranged on the side facing the housing cover 75, in particular axially between the power supply unit 35 and the housing cover 75, wherein the protective gas connection 85 is fluidically connected to the second distribution chamber 220.

[0086] In the embodiment, the flow distributor 90 and / or the outflow unit 125 comprises, for example, a plastic, in particular a thermoplastic, or a metal, in particular aluminum, as the material. It is particularly advantageous if the flow distributor 90 and / or the outflow unit 125 are manufactured using a 3D printing process. In the embodiment, the sensor housing 40 is made, for example, from a metal, for example steel, in particular stainless steel or V2A or V4A steel. This allows, on the one hand, the necessary, complex shape of the flow distributor 90 and the geometry, in particular of the first and second inner walls 105, 130, to be produced in a simple manner, and, on the other hand, a simple (re)production of damaged parts of the system 10 is possible.

[0087] In a further development, structures such as grooves or fins can also be arranged on the first and / or second inner wall 105, 130 in order to further stabilize and direct the outflowing protective gas flow in the protective space.

[0088] To supply the flow distributor 90 with shielding gas 65, the shielding gas 65 is provided by the shielding gas device 15 and introduced into the second distribution chamber 220 via the shielding gas connection 85. In this case, the shielding gas device 15 can, for example, have a relative volume of essentially 0.04 l / min / mm 2 up to 0.4 l / min / mm 2of protective gas with an overpressure relative to an environment 60 of 0.5 bar up to and including 1.5 bar, in particular 0.7 bar up to and including 1.0 bar. The protective gas 65 is purified and, for optimal support of the device according to the invention, contains particles with a maximum size of 0.01 pm to 0.02 pm. This is usually ensured by installing a maintenance unit with a particle filter and oil separator upstream.

[0089] Due to the large-volume design of the second distribution chamber 220, in particular with a significantly larger volume than the volume of the first distribution chamber 211, the flow of the protective gas 65 in the second distribution chamber 220 is calmed. It is particularly advantageous if a maximum first axial chamber extension corresponds to at least 10% up to and including 30% of a maximum first radial chamber extension in the radial direction.

[0090] In the second distribution chamber 220, the shielding gas 65 additionally functions as a cooling medium for cooling the power supply 35 and / or the sensor 30. The shielding gas 65 is heated by the power supply 35 and / or the sensor 30. The heated shielding gas 65 flows into the first distribution chamber 211 via the flow orifice 212.

[0091] The flow orifice 212 forms a first flow resistance and further directs the flow direction of the shielding gas 65 substantially parallel to the axis 55. In the first distribution chamber 211, the flow of the shielding gas 65 is calmed. From the first distribution chamber 211, the shielding gas 65 flows into the channel arrangements 170, 175, 180. Because the fifth total cross-sectional area of ​​the orifice opening areas of the orifice openings 215 is smaller than the first total cross-sectional area, a calm outflow of the shielding gas 65 downstream of the flow orifice 212 via the flow distributor 90 is ensured.

[0092] FIG 5 shows the section A marked in FIG 1 of the purging device 20 shown in FIG 1.

[0093] In FIG. 5, the flow of the protective gas 65 is symbolically represented by arrows in the purging device 20. Furthermore, FIG. 5 shows a graph 230 of a flow velocity v of the protective gas 65 at the blow-out opening 100 plotted over a distance r from the axis 55.

[0094] The shielding gas 65 flows via the channel arrangements 170, 175, 180 to the associated nozzle arrangement 140, 145, 150. A first portion 235 of the shielding gas 65 enters the protective chamber 135 via the first nozzle arrangement 140 at the first channel angle aK of the first channel section 190 to the axis 55 and flows obliquely inward toward the axis 55. The first portion 235 forms a first injection zone 237. The first portion 235 of the shielding gas 65, together with the first injection zone 237, encloses a calm, stable shielding gas cushion 236, which is arranged directly at the housing opening 95 in front of the protective glass 45. In the protective gas cushion 236, the flow velocity of the protective gas is at least 0.01 to 0.5 relative to that at the first passage opening 155. The protective gas cushion 236 essentially prevents particles from being transported directly to the protective glass 45 and from accumulating on the protective glass 45.A second portion 240 of the shielding gas 65 enters the protective chamber 135 from the second channel arrangement 175 via the second nozzle arrangement 145, wherein the orientation of the second portion 240 of the shielding gas 65 is inclined relative to the first portion 235 due to the second channel angle ßK of the second channel section 200 of the second connecting channel 195. The second portion 240 flows along the first portion 235 and is directed more strongly in the direction of the blow-out opening 100 than the first portion 235 of the shielding gas 65. The second portion 240 of the shielding gas 65 prevents the flow of particles in the direction of the first portion 235 and protects the first portion 235 of the shielding gas 65, thereby forming a second injection zone 238.

[0095] A third portion 245 of the shielding gas 65 flows from the first distribution chamber 211 via the third channel arrangement 180 to the third nozzle arrangement 150 and enters the protective space 135 via the third nozzle arrangement 150, wherein the third portion 245 of the shielding gas 65 is directed through the third channel section 210 of the third connecting channel 205. The third portion 245 can be directed parallel to the second inner wall 130 or at an angle to the second inner wall 130, so that the third portion 245 of the shielding gas 65 flows along the second inner wall 130 toward the exhaust opening 100, and a third injection zone 239 of the shielding gas 65 is formed in the protective space 135.

[0096] Furthermore, the above-described volume flows of protective gas 65 ensure that protective gas 65 flows in the protective space 135 primarily laminarly with a Reynolds number of less than 16,000 from the flow distributor 90 in the direction of the blow-out opening 100.

[0097] Due to the tapered design of the outflow unit 125 on the second inner wall 130, starting from the flow distributor 90 in the direction of the blow-out opening 100, the flow velocity v of the protective gas 65 on the axis 55 and thus centered in the protective space 135 is greater than with increasing distance r towards the second inner wall 130.

[0098] By forming the injection zones by means of the first to third nozzle arrangements 140, 145, 150 within the protective space 135, an unwanted inflow of particle-laden contaminated air from the environment 60 via the blow-out opening 100 during operation of the system 10 is effectively prevented, so that both the protective gas 65 blowing from the flow distributor 90 in the direction of the blow-out opening 100 and the protective gas cushion 236 in front of the protective glass 45 prevent particles from adhering to the protective glass 45, even if a backflow of particles into the protective space 135 should occur, thereby ensuring reliable image recording by the sensor 30 via the protective glass 45.

[0099] FIG 6 shows a schematic representation of the outflow unit 125 and the flow distributor 90 of the system 10 shown in FIGS. 1 to 5.

[0100] The outflow unit 125 has a first maximum radial extent b1 perpendicular to the axis 55 directly adjacent to the first inner wall 105 on the second inner wall 130. In a hollow cone-like configuration of the outflow unit 125, the first maximum radial extent can also be referred to as the first maximum inner diameter b1.

[0101] At the exhaust opening 100, the outflow unit 125 has a second maximum radial extent b2 perpendicular to the axis 55 on the second inner wall 130, which can also be referred to as the second inner diameter b2. Along the axis 55 in the axial direction, adjacent to the first inner wall 105, the second inner wall 130 has a first height h1 up to the exhaust opening 100.

[0102] It is particularly advantageous if a first ratio of the first height h1 to the first maximum extension b1 is 0.5 to 2 inclusive. Furthermore, it is advantageous if a second ratio of the second extension b2 to the first extension b1 is 0.5 to 0.8 inclusive, in particular 0.55 to 0.7 inclusive.

[0103] It is particularly advantageous if the first channel section 190 of the first connecting channel 185 is aligned substantially perpendicular to the first wall section 110. In this case, the first channel section 190 can be aligned with a deviation of ± 10° from a perpendicular to the first wall section 110. Furthermore, the second channel section 200 of the second connecting channel 195 can be aligned with a deviation of ± 10° from a perpendicular to the second wall section 115. The third channel section 210 can be aligned in an analogous manner with a deviation of ± 10° from a perpendicular to the third wall section 120.

[0104] In FIG. 6, a sectional plane 250 is plotted between the first maximum extension b1 and the second maximum extension b2. The sectional plane 250 has a second height h2 relative to the first maximum extension b1 at the transition between the first inner wall 105 and the second inner wall 130. The second height h2 is at least 0.2 to 0.5 of the first maximum extension b1.

[0105] Arranged in the section plane 250 are a circle 260, a first ring 265, and preferably a second ring 270. The circle 260 is centered relative to the axis 55 in the section plane 250. The first ring 265 directly adjoins the circle 260 on the radial outside. The second ring 270 directly adjoins the first ring 265 on the radial outside and, in the embodiment, adjoins the second inner wall 130 on the radial outside, for example. One area of ​​the circle 260 essentially corresponds to a second area of ​​the first ring 265 and a third area of ​​the second ring 270.

[0106] The first channel section 190 is aligned with the cutting plane 250 such that it intersects the cutting plane 250 in a first extension 255 of the first channel sections 190 in the circle 260, preferably on the axis 55.

[0107] The second channel section 200 is aligned in the flow distributor 90 such that a second extension 275 of the second channel section 200 intersects the first ring 265 in the intersection plane 250. Preferably, the second extension 275 intersects the first ring 265 in the radial direction at a central position.

[0108] The third channel section 210 is oriented such that a third extension 280 of the third channel section 210 intersects the second ring 270 in the intersecting plane 250. Preferably, the third channel section 210 is oriented such that the third extension 280 intersects the second ring 270 in a central position in the radial direction relative to a maximum radial width of the second ring 270.

[0109] FIG 7 shows a perspective view of a system 10 according to a second embodiment.

[0110] The system 10 is essentially identical to the system 10 explained in FIGS. 1 to 6. The following will exclusively address the differences between the system 10 shown in FIG. 7 according to the second embodiment and the system 10 shown in FIGS. 1 to 6 according to the first embodiment.

[0111] In this embodiment, the purging device 20 is designed as a retrofit component that can be subsequently mounted on the sensor housing 40. For this reason, the purging device 20 has a housing 285. The housing 285 is arranged radially outside the outflow unit 125 and can be formed integrally and from the same material as the outflow unit 125. The shielding gas connection 85 is provided radially outside the housing 285. In this embodiment, for example, two shielding gas connections 85 arranged opposite one another are provided, by way of example, in order to be able to supply sufficient shielding gas 65.

[0112] FIG 8 shows a perspective view of the system 10 shown in FIG 7 according to the second embodiment.

[0113] FIG. 8 clearly shows how the purging device 20 is arranged on the front side of the sensor housing 40 as a retrofit component. The purging device 20 can be attached to the system 10, for example, using an adapter ring 290, wherein the adapter ring 290 is arranged radially outwardly on the protective glass 45 on the side facing the purging device 20.

[0114] FIG 9 shows the system 10 shown in FIGS. 7 and 8, whereby in FIG 9 the illustration of the blow-out device 20 is omitted.

[0115] The adapter ring 290 is, for example, fastened radially on the outside to the sensor housing 40 by means of a screw connection, wherein the adapter ring 290 does not cover the protective glass 45 to such an extent that sufficient recording by means of the sensor 30 is possible.

[0116] FIG 10 shows a sectional view along a section plane BB shown in FIG 7 through the system 10 shown in FIG 7.

[0117] Instead of the sensor housing 40, as shown in FIGS. 1 to 6, the housing 285 of the purging device 20, together with a second outer circumferential side 295 of the outflow unit 125, delimits the first distribution chamber 211 and the second distribution chamber 220. The second distribution chamber 220 is arranged, for example, on a side facing away from the flow distributor 90, radially on the outside in the axial direction of the outflow unit 125. The protective gas connection 85 opens radially outward into the second distribution chamber 220. The second distribution chamber 220 is designed, for example, as a first annular chamber and is arranged radially on the outside in the circumferential direction around the axis 55, radially on the outside of the outflow unit 125.

[0118] The flow orifice 212 is arranged axially between the first distribution chamber 211 and the second distribution chamber 220. The flow orifice 212 can, for example, be conically shaped and have a plurality of orifice openings 215, which are, for example, slot-shaped in the flow orifice 212. The orifice openings 215 can, for example, be arranged on a common circle around the axis 55. Each of the orifice openings 215 has an orifice opening area.

[0119] The first distribution chamber 211 is arranged radially facing the flow distributor 90. The first distribution chamber 211 is also delimited radially on the outside by the housing 285 and radially on the inside by the outflow unit 125. The flow distributor 90 and the adapter ring 290 adjoin the first distribution chamber 211 axially and delimit the first distribution chamber 211 in the axial direction. The first to third channel arrangements 170, 175, 180 open at the first distribution chamber 211.

[0120] During operation, the shielding gas 65 is provided under pressure via the shielding gas connection 85, analogous to FIGS. 1 to 6. The shielding gas 65 flows into the second distribution chamber 220 via the shielding gas connection 85. Pressure fluctuations or flow irregularities in the shielding gas 65 are equalized in the second distribution chamber 220 by the larger design of the second distribution chamber 220 compared to the first distribution chamber 211.

[0121] From the second distribution chamber 220, the shielding gas 65 flows through the apertures 215 into the first distribution chamber 211. The small openings of the apertures 215 align the shielding gas 65 flowing in the axial direction, and in the first distribution chamber 211, the shielding gas 65 is again equalized and calmed. The shielding gas 65 flows from the first distribution chamber 211 into the first to third channel arrangements 170, 175, 180. From the channel arrangements 170, 175, 180, as explained in FIGS. 1 to 6, the shielding gas 65 is guided into the protective space 135 via the nozzle arrangements 140, 145, 150 and from the protective space 135 via the exhaust opening 100 into the environment 60.

[0122] The second embodiment shown in FIGS. 7 to 10 has the advantage that existing systems 10 can be retrofitted with the purging device 20 or the existing system 10, in particular the sensor housing 40, does not need to be further adapted.

[0123] It is particularly advantageous if, for example, an external thread 296 is arranged on the adapter ring 290, wherein the housing 285 can be screwed onto the external thread 296 by means of an internal thread 297. FIG. 11 shows a perspective view of a system 10 according to a third embodiment.

[0124] The system 10 is a combination of the first and second embodiments of the system 10 shown in FIGS. 1 to 10. The following primarily describes the differences between the system 10 shown in FIG. 12 according to the third embodiment and the system 10 shown in FIGS. 1 to 6 according to the first embodiment. In particular, the purging device 20 and the sensor housing 40 are integrated, so that the sensor housing 40 is also part of the purging device 20.

[0125] FIG 12 shows a semi-longitudinal section along a section plane EE shown in FIG 11 through the system 10 shown in FIG 11 according to the third embodiment.

[0126] The housing interior 50 of the sensor housing 40 is subdivided, for example, into a housing interior section 298 and a second housing interior section 299 separated from the first housing interior section 298. The second housing interior section 299 is arranged on the side facing the protective glass 45, and the first housing interior section 298 is arranged on a side facing the housing cover 75. The power supply 35 is arranged in the first housing interior section 298, and the sensor 30 is arranged in the second housing interior section 299.

[0127] The shielding gas connection 85 is arranged, for example, on the housing cover 75. A fourth channel arrangement 300 with at least one fourth connecting channel 305 is arranged in the housing cover 75.

[0128] The housing 285 is arranged, for example, radially on the outside of the sensor housing 40. The housing 285, together with the sensor housing 40, delimits a first annular channel 310, which is arranged on the end face on the side facing the housing cover 75. The first annular channel 310 is formed around the axis 55 radially on the outside of the sensor housing 40 and in the circumferential direction around the sensor housing 40. The first annular channel 310 forms the second distribution chamber 220. For example, the housing cover 75 is guided radially outward so far that the housing cover 75 closes both the housing 285 and the sensor housing 40. The fourth channel arrangement 300 opens into the first annular channel 310 and fluidically connects the protective gas connection 85 to the first annular channel 310. Axially on a side facing away from the housing cover 75, the housing 285 and the sensor housing 40 form the flow orifice 212 with at least one orifice opening 215.The orifice opening 215 can be channel-shaped. Axially adjacent to the flow orifice 215, the sensor housing 40 and the housing 285 form a second annular channel 325, which is arranged radially outside the sensor housing 40. The second annular channel 325 can have an annular basic shape. The second annular channel 325 further forms the first distribution chamber 211. The second annular channel 325 is fluidically connected to the first annular channel 310 via the flow orifice 212.

[0129] The power supply 35 is arranged radially inwardly in the sensor housing 40, on the side facing the housing cover 75. At least one first channel feed 315 is arranged in the sensor housing 40, which branches off from the second annular channel 325 and opens into the housing interior 50, in particular into the first housing interior section 298. The protective gas 65 can be introduced at least partially into the housing interior 50, in particular into the first housing interior section 298, via the first channel feed 315 in order to cool the power supply 35 during operation of the system 10.

[0130] A first channel outlet 320 is arranged in the sensor housing 40, axially offset from the first channel inlet 315. The first channel outlet 320 opens radially inward into the housing interior 50 of the sensor housing 40, in particular into the first housing interior section. The first channel outlet 320 is arranged at a distance from the first channel inlet 315 in the axial direction on a side facing away from the housing cover 75.

[0131] A calming structure 330 is arranged in the second annular channel 325 downstream of the first channel outlet 320. The calming structure 330 preferably deflects the shielding gas 65 several times in the circumferential direction within the second annular channel 325 in order to equalize the flow of the shielding gas 65.

[0132] Downstream of the optional calming structure 330, in the axial direction on the side facing away from the housing cover 75, a second channel inlet 335 is provided, and axially spaced apart on the side facing away from the housing cover 75, a second channel outlet 340 is provided. The second channel inlet 335 extends radially inward through the sensor housing 40 and opens into the housing interior 50 of the sensor housing 40, in particular into the second housing interior section 299 at the sensor 30. The second channel outlet 340 is axially spaced apart, preferably so far that the sensor 30 is arranged between the second channel inlet 335 and the second channel outlet 340. The second channel outlet 340 also extends through the sensor housing 40. The second channel outlet 340 opens into the second housing interior section 299.

[0133] Downstream of the second channel discharge 340, a rib structure 345 is arranged in the second annular channel 325, for example. The rib structure 345 can, for example, have a plurality of ribs 350 projecting into the second annular channel 325. The ribs 350 extend parallel to the axis 55 and serve to align the protective gas 65 parallel to the axis 55.

[0134] The first to third channel arrangements 170, 175, 180 are arranged on the side facing away from the housing cover 75 on the second annular channel 325 forming the first distribution chamber 211.

[0135] FIG 13 shows a sectional view along a section plane CC shown in FIG 12 through the system 10.

[0136] For example, the power supply unit 35 is arranged in the first housing interior section 298 of the sensor housing 40, into which both the first channel feed 315 and the first channel discharge 320 open.

[0137] FIG 14 shows a sectional view along the section plane EE shown in FIG 11 through the system 10, and FIG 15 shows a sectional view along a section plane DD shown in FIG 12 through the system 10 shown in FIG 12.

[0138] The operation of the system 10 shown in FIGS. 11 to 15 is briefly explained below.

[0139] The purified shielding gas 65 is introduced or supplied into the system 10 via the shielding gas connection 85. The shielding gas 65 flows from the shielding gas connection 85 via the fourth channel arrangement 300 into the first annular channel 310, which forms the second distribution chamber 220. Due to the large-volume design resulting from the large outer diameter of the second distribution chamber 220, the flow of the shielding gas 65 in the second distribution chamber 220 is equalized and calmed.

[0140] From the second distribution chamber 220, the protective gas 65 flows through the flow orifice

[0141] 212 radially inward into the second annular channel 325, which forms the first distribution chamber 211. For example, a first portion of the protective gas 65 flowing into the second annular channel 325 flows via the first channel inlet 315 into the first housing interior section 298 and cools the power supply unit 35. The heated first portion of the protective gas 65 flows back radially outward into the second annular channel 325 via the first channel outlet 320 and opens into the second annular channel 325, axially offset from the first channel inlet 315.

[0142] The second part of the protective gas 65 remaining in the second annular channel 325 flows in the axial direction from the flow aperture 212 in the direction of the protective glass 45 and is deflected several times in the circumferential direction, for example by the calming structure 330.

[0143] After flowing through the calming structure 330, the shielding gas 65 flows radially inward via the second channel inlet 335 into the second housing interior section 299 and flows around the sensor 30. In the process, the shielding gas 65 cools the sensor 30. In the axial direction, the shielding gas 65 flows along the sensor 30 in the direction of the protective glass 45 and flows radially outward again via the second channel outlet 340 into the second annular channel 325.

[0144] The shielding gas 65 flows further in the second annular channel 325 to the rib arrangement 345, which aligns the shielding gas 65 parallel to the axis 55. From the second annular channel 325, the shielding gas 65 flows through the rib arrangement 345 into the distribution channels 170, 175, 180 and forms the injection zones 237, 238 explained in the context of FIGS. 1 to 6 in the protective space 135.

[0145] The design of the system 10 described in FIGS. 11 to 15 has the advantage that the system 10, together with the purging device 20, is particularly slim in the radial direction. As a result, the installation space requirement for the system 10 shown in FIGS. 11 to 15 is particularly small.

[0146] FIG 16 shows a schematic sectional view through a system 10 according to a fourth embodiment for a large-scale industrial plant.

[0147] The system 10 is essentially identical to the system 10 explained in FIGS. 1 to 6. The following will exclusively address the differences between the system 10 shown in FIG. 7 according to the second embodiment and the system 10 shown in FIGS. 1 to 6 according to the first embodiment. In addition, the system 10 has a transmitting device 355 which is designed to emit electromagnetic radiation 360, for example laser radiation, with preferably a wavelength of 300 nm up to and including 900 nm. The transmitting device 355 is arranged, for example, next to the sensor 30. Means can be arranged between the sensor 30 and the transmitting device 355 in order to prevent a direct signal path from the transmitting device 355 to the sensor 30.

[0148] The protective glass 45 is transparent to the electromagnetic radiation 360 emitted by the transmitting device 355, so that the electromagnetic radiation 360 enters the protective chamber 135 through the protective glass 45. The electromagnetic radiation 360 can be directed at a component 365 of the large-scale industrial plant to be evaluated. The large-scale industrial plant reflects the emitted electromagnetic radiation 360 at least partially toward the system 10. The reflected radiation 370 enters the protective chamber 135 through the exhaust opening 100. The protective gas cushion 236 prevents particles from being transported directly to the protective glass 45 and from accumulating on the protective glass 45.The protective gas cushion 236 thus ensures that the emitted electromagnetic radiation 360 can reach the component 365 of the large-scale industrial plant to be evaluated in the best possible way, and that the reflected radiation 365 can reach the sensor 30 via the protective glass 45 and the sensor 30 can detect the reflected radiation 365 particularly well.

[0149] List of reference symbols

[0150] 10 systems

[0151] 15 Protective gas device

[0152] 20 Purging device

[0153] 25 Sensor device

[0154] 30 Sensor for detecting electromagnetic radiation, in particular

[0155] Pyrometer, optical sensor, UV, IR, laser radiation

[0156] 35 Power supply

[0157] 40 sensor housings

[0158] 45 protective glass

[0159] 50 Housing interior

[0160] 55 Axis

[0161] 60 particle and / or vapor-laden environment

[0162] 65 shielding gas

[0163] 70 first housing part

[0164] 75 Housing cover

[0165] 80 second housing part

[0166] 85 Shielding gas connection

[0167] 90 flow distributors

[0168] 95 Housing opening

[0169] 100 exhaust opening

[0170] 105 first interior wall

[0171] 110 first wall section

[0172] 115 second wall section

[0173] 120 third wall section

[0174] 125 outflow unit

[0175] 126 first outer circumferential side

[0176] 130 second interior wall

[0177] 135 shelter

[0178] 140 first nozzle arrangement

[0179] 145 second nozzle arrangement

[0180] 150 third nozzle arrangement

[0181] 155 first passage opening

[0182] 160 second passage opening

[0183] 165 third passage opening

[0184] 170 first channel arrangement

[0185] 175 second channel arrangement third channel arrangement first connecting channel first channel section second connecting channel second channel section third connecting channel third channel section first distribution chamber

[0186] Flow orifice

[0187] Aperture opening second distribution chamber

[0188] sleeve

[0189] Graph first part

[0190] Protective gas cushion first injection zone second injection zone second part third part

[0191] Cutting plane first extension

[0192] Circle first ring second ring second extension third extension

[0193] Housing

[0194] Adapter ring second outer circumferential side

[0195] external thread

[0196] Internal thread first housing interior section second housing interior section fourth channel arrangement fourth connecting channel first annular channel first channel feed first channel discharge 325 second annular channel

[0197] 330 Calming structure

[0198] 335 second sewer feed

[0199] 340 second sewer discharge

[0200] 345 rib structure

[0201] 350 ribs

[0202] 355 transmitting device

[0203] 360 electromagnetic radiation

[0204] 365 components to be evaluated

[0205] 370 reflected radiation b1 maximum first extension b2 maximum second extension h1 first height h2 second height r distance v flow velocity a first wall angle ß second wall angle

[0206] Y third wall angle ö fourth wall angle aK first channel angle ßK second channel angle yK third channel angle

Claims

Patent claims 1. Purge device (20) for protecting a sensor device (25), in particular a protective glass (45) of the sensor device (25), in a particle- and / or vapor-laden environment (60), - wherein the blow-out device (20) has at least one flow distributor (90), a housing opening (95) and a blow-out opening (100), - wherein the blow-out device (20) extends along an axis (55) between the housing opening (95) and the blow-out opening (100) arranged opposite the housing opening (95), - wherein the blow-out device (20) encloses a protective space (135) between the housing opening (95) and the blow-out opening (100), - wherein a sensor device (25) can be arranged at the housing opening (95) and the exhaust opening (100) can be directed towards the dust-laden environment (60), - wherein the flow distributor (90) has at least one first nozzle arrangement (140) with at least one first passage opening (155), a first inner wall (105) and a first channel arrangement (170) with at least one first connecting channel (185), - wherein the first inner wall (105) extends from the housing opening (95) in the direction of the blow-out opening (100) and encloses the protective space (135) at least in sections, - wherein the first nozzle arrangement (140) is arranged at a distance from the housing opening (95) on the first inner wall (105), - wherein the first connecting channel (185) opens with a first channel section (190) at the first passage opening (155), which is aligned obliquely inclined to the axis (55), - wherein a pressurised protective gas (65) can be guided to the first passage opening (155) and from the first passage opening (155) into the protective space (135) via the first connecting channel (185), - wherein the first nozzle arrangement (140) has a plurality of first passage openings (155) arranged at a distance from one another in the circumferential direction around the axis (55), at least 10 to 25, in particular at least 15 to 25, - wherein each of the first passage openings (155) is fluidically connected to a respective associated first channel section (190) of the first connecting channel (185), - wherein each of the first channel sections (190) is arranged at a first channel angle (aK) obliquely to the axis (55), - wherein the flow distributor (90) has a second nozzle arrangement (145) with at least one second passage opening (160) and a second channel arrangement (175) with at least one second connecting channel (195), - wherein the second nozzle arrangement (145) is arranged offset in the axial direction relative to the axis (55) relative to the first nozzle arrangement (140), - wherein each second connecting channel (195) has a second channel section (200), - wherein the second channel section (200) opens at the second passage opening (160) and is aligned at a second channel angle (ßK) inclined to the axis (55) subsequent to the second passage opening (160), - wherein the second channel angle (ßK) is different, in particular smaller, than the first channel angle (aK), - wherein the second nozzle arrangement (145) has a plurality of second passage openings (160) arranged at a distance from one another in the circumferential direction around the axis (55), at least 10 to 25, in particular at least 5 to 25, - wherein each of the second passage openings (160) is fluidically connected to the respective one second channel section (200).

2. Blow-out device (20) according to claim 1, - comprising an outflow unit (125), - wherein the first inner wall (105) is widened from the housing opening (95) towards the blow-out opening (100), - wherein the outflow unit (125) is arranged on a side of the flow distributor (90) facing away from the housing opening (95) and is connected radially outwardly to the blow-out opening (100), - wherein the outflow unit (125) encloses the protective space (135) with a second inner wall (130) on the circumference, - wherein the second inner wall (130) is tapered from the flow distributor (90) towards the blow-out opening (100).

3. Blow-out device (20) according to claim 2, - wherein the second inner wall (130) adjacent to the flow distributor (90) has a first maximum extension (b1) perpendicular to the axis (55), - wherein in the axial direction relative to the axis (55), the second inner wall (130) has a first height (h1) between the blow-out opening (100) and adjacent to the flow distributor (90), wherein a first ratio of the first height (h1) to the first maximum extension (b1) is 0.5 to 2 inclusive.

4. Blow-out device (20) according to claim 2 or 3, - wherein the second inner wall (130) adjacent to the flow distributor (90) has a first maximum extension (b1) perpendicular to the axis (55), - wherein the second inner wall (130) at the blow-out opening (100) has a second maximum extension (b2) perpendicular to the axis (55), - wherein a second ratio of the second maximum extension (b2) to the first maximum extension (b1) is 0.5 to 0.8 inclusive, in particular 0.55 to 0.7 inclusive.

5. Blow-out device (20) according to one of the preceding claims, - comprising a first distribution chamber (211), - wherein the first channel arrangement (170) opens into the first distribution chamber (211) with the first connecting channel (185) on a side facing away from the first passage opening (155), - wherein the protective gas (65) can be guided to the first connecting channel (185) via the first distribution chamber (211).

6. Blow-out device (20) according to one of the preceding claims, - wherein the first passage opening (155) has a first exit surface, - wherein the first channel section (190) has a first channel cross-sectional area spaced from the first passage opening (155), - wherein the second passage opening (160) has a second exit surface, - wherein the second channel section (200) has a second channel cross-sectional area spaced from the second passage opening (160), - wherein a third ratio of a first total cross-sectional area formed from a first sum of the first and second outlet areas to a second total cross-sectional area formed from a second sum of the first and second channel cross-sectional areas is 0.1 to 0.6 inclusive, in particular 0.2 to 0.5 inclusive.

7. Blow-out device (20) according to one of the preceding claims, - wherein the first passage opening (155) has a first exit surface, - wherein the second passage opening (160) has a second exit surface, - wherein a fourth ratio of a third total cross-sectional area formed from a third sum of the first exit areas to a fourth total cross-sectional area formed from a fourth sum of all exit areas of the passage openings (155, 160, 165) is 0.2 to 0.5 inclusive, in particular 0.25 to 0.45 inclusive.

8. Blow-out device (20) according to one of the preceding claims, - wherein the first inner wall (105) has a first wall section (110), - wherein the first wall section (110) is conical, - wherein the first wall section (110) encloses a first wall angle (a) with the axis (55), - wherein the first wall angle (a) is preferably 40° to 70° inclusive.

9. Blow-out device (20) according to claim 8, - wherein the first inner wall (105) has a second wall section (115), - wherein the second wall section (115) is conical in shape, - wherein the second wall section (115) encloses a second wall angle (ß) with the axis (55), - wherein the second wall angle (ß) is greater than the first wall angle (α) and less than 90°, - wherein the second wall section (115) is preferably arranged radially outwardly of the first wall section (110).

10. System (10) - with a sensor device (25), a protective gas device (15) and a blow-out device (20) according to one of the preceding claims, - wherein the sensor device (25) comprises a sensor (30), a sensor housing (40) and a protective glass (45), - wherein the sensor housing (40) encloses a housing interior (50) in which the sensor (30) is arranged, - wherein the protective glass (45) is arranged at the housing opening (95) and closes the housing interior (50), - wherein the protective gas device (15) is fluidically connected to the blow-out device (20) and is designed to provide the pressurized protective gas (65).

11. Method for operating a purging device (20) according to one of claims 1 to 9, - wherein a pressurized protective gas (65) is supplied to the first nozzle arrangement (140) via the first connecting channel (185), - wherein the protective gas (65) is directed through the first channel section (190) and is guided in an aligned manner via the first passage opening (155) into the protective space (135), - wherein the protective gas (65) flows in the direction of the blow-out opening (100) in the protective space (135) and forms a protective gas cushion (236) at the housing opening (95), - wherein the protective gas (65) exits the protective chamber (135) at the exhaust opening (100), - wherein preferably the protective gas (65) guides particles entering via the blow-out opening (100) out of the protective space (135) and / or reduces the entry of particles into the protective space (135) via the blow-out opening (100).

12. Method according to claim 11, - wherein the protective gas (65) with a Reynolds number of less than 16,000 flows in the protective space (135) from the first nozzle arrangement (140) in the direction of the blow-out opening (100), - wherein preferably a relative volume with respect to the outlet opening of substantially including 0.04 l / min / mm 2 up to 0.4 l / min / mm 2 of protective gas (65) is fed into the protective chamber (135), - wherein the protective gas (65) is preferably supplied at an overpressure relative to an environment (60) of 0.5 bar up to and including 1.5 bar, in particular 0.7 bar up to and including 1.0 bar.

Citation Information

Patent Citations

  • Optical surface inspection device for mill roll

    EP0547227A1

  • Device for cleaning at least one lens of at least one camera, camera system and camera holder, comprising such a device, and method

    DE102019101092A1

  • Cleaning device for cleaning a surface of a sensor device

    DE102019214705A1

  • DEVICE FOR KEEPING AN OPTICAL ELEMENT CLEAN

    DE2912419A1

  • Device for cleaning a driving assistance camera of a motor vehicle

    EP3006278A1