Blowout device
The blowing device addresses uneven pressure distribution and energy inefficiency by using angled exhaust passages to create a uniform airflow pattern, enhancing cleaning and cooling efficiency.
Patent Information
- Application Number
- JP2025542391
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-01-24
- Filing Date
- 2024-01-19
- Publication Date
- 2026-02-06
AI Technical Summary
Existing air blowing devices, such as air knives and air manifolds, face issues with uneven pressure distribution and energy inefficiency due to the combination of high-velocity air streams from adjacent nozzles creating blind spots and excessive energy use at the center of the airflow, leading to incomplete cleaning or cooling effects.
A blowing device design featuring groups of primary exhaust passages angled uniformly and surrounded by secondary exhaust passages angled away, which creates a co-mingled gas jet with reduced central peak pressure and broader, more even pressure distribution across the surface.
The design achieves improved surface coverage with reduced noise and energy consumption by minimizing turbulence and maintaining consistent pressure across a wide area without increasing inlet pressure.
Smart Images
Figure 2026504675000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a blowing device, such as an air knife or air manifold, for supplying pressurized air to the surface of an object. [Background technology]
[0002] Blowing devices, often referred to as air knives, air manifolds, and air (nozzle) manifolds, have been used for many years in many industrial and manufacturing processes to deliver pressurized air against the surfaces of stationary or moving objects for the purposes of blowing off, i.e., removing, liquids or debris from the surfaces of stationary or moving objects, or for the purposes of cooling or heating the surfaces of stationary or moving objects.
[0003] A typical air knife consists of a manifold or plenum with an elongated, narrow air slot, either continuous or divided into multiple, more numerous, small openings, allowing pressurized air to exit the manifold or plenum along the length of the air slot. The slot is intended to provide a continuous air flow or jet along the length of the slot. The air knife is generally positioned in close proximity to the part being blown off, and any interruption in the continuous air flow can adversely affect the blowing effect.
[0004] An air nozzle or air manifold consists of a manifold or plenum from which multiple air outlet nozzles with circular or elongated openings are positioned at various intervals along the length of the manifold. An air nozzle / manifold does not provide a continuous air flow along its length like an air knife. Instead, the orifice of each outlet nozzle delivers a much larger air flow, typically in the form of a high-velocity air stream, in a concentrated area. Problems can arise when two adjacent air streams impinge on a surface at the same spot from different angles, as the resulting combined air flow can create a "blind spot" that lacks the desired cleaning effect and fails to remove liquid or debris.
[0005] Important characteristics for a compressed air blower are noise level, consumption, power and blowing pattern. These four parameters depend on the pressure at the blower and are usually specified at different pressures.
[0006] Many air applications today require a rectangular jet cross-section that maximizes the width of the airflow and minimizes its height. It is also desirable to minimize noise levels and air consumption. One way to achieve this is to use several smaller outlet nozzles instead of one large one. The size and center-to-center spacing of the outlet nozzles are carefully calculated to minimize the sound level at a given pressure. The outlet nozzles can be arranged in various patterns to achieve a particular spray pattern. The cross-sectional area of the outlet openings in the nozzle and the distance between the outlet openings together determine the cross-sectional area of the nozzle.
[0007] To determine the spray pattern, the relative pressure generated on a flat surface from opposing manifolds at 90° to the surface can be measured.
[0008] For a given design of outlet channel pattern, if it is desired to increase the relative pressure across the width of the spray pattern, this can only be achieved by adjusting the input pressure.
[0009] The drawback of increasing the pressure is that it tends to result in a disproportionately high pressure increase at the center of the air jet, rather than a proportional increase across the entire width of the spray pattern, and is rarely needed with this type of nozzle. This effectively means using an unnecessary amount of energy to increase the relative pressure across the entire surface covered by the airflow. Therefore, there is a need for an air blowing arrangement that can provide more even coverage of the surface for a given pressure and a given cross-sectional area of the nozzle of the air blowing arrangement. Summary of the Invention
[0010] The present invention aims to overcome or at least minimize the above-mentioned problems by providing a blowing device having the features of claim 1. Such a blowing device has a group of at least two adjacent central exhaust passages that direct a pressurized gaseous fluid from the blowing device at a first angle, the group of central exhaust passages being surrounded on each side by at least one exhaust passage oriented at an angle away from the nearest central exhaust passage. Due to the presence of at least two adjacent central exhaust passages directed in the same direction and the presence of further exhaust passages directed away from this direction, the resulting co-mingled gas jet formed from the pressurized gas exiting these exhaust passages surprisingly exhibits a smaller central peak pressure than a blowing device having a single central exhaust passage directed in the first direction and arranged between further exhaust passages oriented at an angle away from the central exhaust passage. [Brief explanation of the drawings]
[0011] [Figure 1] 1A-1D are schematic side, plan and end views of a first embodiment of a blowing device according to the present invention; [Figure 2] 1A-1D are schematic side, plan and end views of a first embodiment of a blowing device according to the present invention; [Figure 3] FIG. 10 shows examples of relative pressures measured at positions across a surface using different angles relative to the exhaust passage. DETAILED DESCRIPTION OF THE INVENTION
[0012] 1a to 1c show, not to scale, side, plan, and end views of a blowing device 1 according to a first embodiment of the present invention. The blowing device 1 comprises a housing 3 having an outer wall 5 enclosing a chamber 7. The housing is in the form of a box, shown in this example as substantially rectangular, but may have any suitable shape. The box has an outlet face 9, indicated by arrow 11, intended to face towards an item to be blown with air. Preferably, the outlet face 9 is flat and elongated, with a major axis 13 extending in a first direction X and a minor axis 15 extending in a direction Y perpendicular to the major axis 13. The outer wall 5 has a pressurized gas supply inlet 17 adapted to be connected to a pressurized gas supply (not shown).
[0013] The outlet face 9 is provided with a plurality of primary exhaust passages 19 and a plurality of secondary exhaust passages 21, each of which extends from the chamber 7 through the outer wall 5 and opens out at an opening 22 in the outlet face 9. The primary and secondary exhaust passages are shown arranged in a straight line along the longitudinal centerline of the outlet face to provide symmetry to this embodiment of the invention, but may be arranged in other manners, such as parallel to the longitudinal centerline or at an angle to the centerline.
[0014] The plurality of primary exhaust passages form a group 23 of primary exhaust passages including at least two adjacent primary exhaust passages 19 arranged to direct the pressurized gaseous fluid at a first angle α from the outlet plane. Preferably, this angle is perpendicular to the outlet plane. If the blower device is intended to provide a jet of air that is substantially symmetrical along the longitudinal centerline, the center of the group of primary exhaust passages coincides with the midpoint of the longitudinal centerline, as shown in the figure. If the blower device is intended to generate an asymmetrical stream of air, the center of the primary exhaust passage is located to one side of the midpoint of the longitudinal centerline.
[0015] The group of primary exhaust passages forms a line, preferably a straight line, followed at each end in the direction of the longitudinal centerline by at least one secondary exhaust passage 21 directed at an angle β away from the angle α in the direction along the longitudinal centerline. As shown in Figure 1a), a central group 23 of two primary exhaust passages 19 has three secondary exhaust passages 21 located to its left that direct pressurized gas to the left at the angle β, and three secondary exhaust passages 21 located to its right that direct pressurized gas to the right at the angle β.
[0016] In an embodiment of the present invention, there are two primary exhaust passages in the group of primary exhaust passages, and multiple groups of three secondary exhaust passages on either side of the group of primary exhaust passages, for a total of six secondary exhaust passages arranged in these multiple groups, but there may be more than two primary exhaust passages in the group of primary exhaust passages, and the number of secondary exhaust passages on each side of the group of primary exhaust passages may be any number greater than or equal to one.
[0017] The center-to-center distance between adjacent exhaust passages may be the same for all exhaust passages, or may be different for some adjacent exhaust passages. For example, the center-to-center distance between adjacent exhaust passages may be greater for adjacent exhaust passages further away from the primary exhaust passage than for adjacent exhaust passages closer to the primary exhaust passage, or vice versa. The cross-sectional area of the exhaust passages may be the same for all exhaust passages, or may be different.
[0018] Figures 2a) to 2c) show, not to scale, schematic side, plan and end views of a blowing device 1 according to a second embodiment of the present invention, and the same reference numerals used in Figures 1a) to 1c) are used for similar elements in Figures 2a) to 2c). The blowing device 1 thus comprises a housing 3 having an outer wall 5 enclosing a chamber 7. The housing is in the form of a box, and in this example is shown as being essentially rectangular, but may have any suitable shape.
[0019] The box has an outlet face 9 intended to face towards an object against which the air is to be blown, as indicated by arrow 11. Preferably, the outlet face 9 is flat and elongated, with a major axis centre line 13 extending in a first direction X and a minor axis centre line 15 extending orthogonal to the major axis centre line in a direction Y. The outer wall 5 has a pressurized gas supply inlet 17 adapted to be connected to a source of pressurized gas (not shown).
[0020] The outlet face 9 is provided with a plurality of primary exhaust passages 19 and a plurality of secondary exhaust passages 21, each of which extends from the chamber 7 through the outer wall 5 and opens to the exterior at an opening 22 in the outlet face 9. The primary and secondary exhaust passages are shown arranged in a straight line along the longitudinal centerline of the outlet face to provide symmetry to this embodiment of the invention, but may be arranged in other manners, such as parallel to the longitudinal centerline or at an angle relative to the centerline.
[0021] The plurality of primary exhaust passages form a group 23 of primary exhaust passages including at least two adjacent primary exhaust passages 19 arranged to direct the pressurized gaseous fluid at a first angle α from the outlet plane. This angle may be perpendicular to the outlet plane or may be an angle of 10° or less. If the blower device is intended to provide a jet of air that is substantially symmetrical along the longitudinal centerline, the center of the group of primary exhaust passages coincides with the midpoint of the longitudinal centerline, as shown. If the blower device is intended to generate an asymmetrical stream of air, the center of the primary exhaust passage is located to one side of the midpoint of the longitudinal centerline.
[0022] The group of primary exhaust passages preferably forms a straight line and is followed at each end in the direction of the longitudinal centerline by at least one secondary exhaust passage 21 directed at an angle β away from the angle α in the direction along the longitudinal centerline. As shown in FIG. 2b), the central group 23 comprises two primary exhaust passages 19, on each side of which, immediately outside this group of primary exhaust passages, a pair of secondary exhaust passages 25 is positioned, said secondary exhaust passages being arranged parallel to the minor axis centerline 15. Furthermore, outside each group of two secondary exhaust passages, a single secondary exhaust passage is arranged on the major axis centerline. This single secondary exhaust passage is followed by a further pair of secondary exhaust passages also parallel to the minor axis centerline 15.
[0023] Figure 3 shows experimental results from a blower with a row of exhaust passages arranged in a straight line. The blower has two central primary exhaust passages pointed straight towards a flat pressure measurement surface. Multiple secondary exhaust passages with the same cross-sectional area are located on either side of the pair of primary exhaust passages.
[0024] The inlet pressure is 0.5 MPa, the distance to the pressure measurement surface is 200 mm, and the face of the surface is 290 mm x 310 mm. The face of the blower facing the pressure measurement surface is 43 mm x 7 mm. The face of the blower facing the pressure measurement surface has two central primary exhaust passages and 14 secondary exhaust passages (seven on either side of the central primary exhaust passage), arranged with a center-to-center spacing of 2.7 mm. All exhaust passages are circular with an opening diameter (D) of 0.9 mm.
[0025] The use of two central primary exhaust passages minimizes turbulence and therefore reduces noise levels compared to using one larger exhaust with the cross-sectional area of two smaller exhausts. Additionally, the use of a single central primary exhaust can create a pressure drop in the center when blowing air onto a flat surface.
[0026] A series of experiments was conducted using secondary exhaust passages angled away from the primary exhaust passage at different angles with the same inlet pressure. The angles tested were 0°, 1.5°, 2.5°, 4°, and 6°. As can be seen in Figure 3, increasing the angle of the secondary exhaust passage results in a lower, broader, and more pronounced peak, which is desirable.
[0027] This provides good coverage of the surface without excessively high peak pressures in the center that would simply waste energy. Surprisingly, at an angle of about 6°, the peak not only broadens but also forms a plateau that provides a nearly constant pressure over a wide range of positions. This is desirable because it provides good cleaning or cooling effects over a wide area without requiring an increase in inlet pressure.
[0028] In all embodiments of the present invention, the secondary exhaust passages are inclined at the same angle β away from the nearest primary exhaust passage. Preferably, the angle β is between 1 and 10 degrees in the direction away from the nearest primary exhaust passage, more preferably, the angle β is between 2 and 9 degrees. Even more preferably, the angle β is between 3 and 8 degrees, even more preferably, the angle β is between 4 and 7.5 degrees, and most preferably, the angle β is between 5 and 7 degrees.
[0029] It is also contemplated that the angle β may change as the distance of the secondary exhaust passage from the nearest primary exhaust passage increases. For example, the secondary exhaust passage nearest the primary exhaust passage may be inclined at an angle β away from the primary exhaust passage, the next secondary exhaust passage may be inclined at an angle of β+x degrees, the next next secondary exhaust passage may be inclined at an angle of β+y degrees, the following secondary exhaust passage may be inclined at an angle of β+z degrees, and so on (where z>y>x).
[0030] Preferably, the maximum diameter or width (D) of any exhaust passage opening 22 is not greater than 1.0 mm and not less than 0.5 mm, more preferably not greater than 0.9 mm and not less than 0.6 mm. Preferably, all of the primary exhaust openings have substantially the same cross-sectional area as each other, and / or all of the secondary exhaust openings have substantially the same cross-sectional area as each other, or all of the exhaust passage openings have substantially the same cross-sectional area.
[0031] Preferably, the minimum center-to-center distance between adjacent exhaust passages is 3 to 5 times the maximum diameter or width (D) of the opening of the widest exhaust passage among the adjacent exhaust passages.
Claims
1. A blowing device (1) for supplying pressurized air to a surface of an object, comprising: The blowing device (1) a pressurized gaseous fluid inlet (17); a plurality of primary and secondary exhaust passages (19, 21); the plurality of primary and secondary exhaust passages (19, 21) communicate with an outlet surface (9) of the housing and open to the outside at the outlet surface; The exhaust passage jointly exhausts the fluid from the housing (3), the plurality of exhaust passages comprising a group (23) of at least two adjacent primary exhaust passages (19) arranged in a line and directing the pressurized gaseous fluid at a first angle α from the outlet face (9); said group (23) of adjacent primary exhaust passages is followed at each end of said line by at least one secondary exhaust passage (21) oriented at an angle β away from the nearest primary exhaust passage; Blowing device (1).
2. the at least one secondary exhaust passage (21) is disposed at an angle β of 1 to 10 degrees from the nearest primary exhaust passage (19); The blowing device according to claim 1 .
3. The angle β is equal to or greater than 2 degrees and equal to or less than 9 degrees. The blowing device according to claim 1 .
4. The angle β is preferably 3 degrees or more and 8 degrees or less, more preferably 4 degrees or more and 7.5 degrees or less, and most preferably 5 degrees or more and 7 degrees or less. The blowing device according to claim 3 .
5. the number of the primary exhaust passages (19) in the group of at least two primary exhaust passages is greater than or equal to 2 and less than or equal to 6; The blowing device according to any one of claims 1 to 4.
6. the openings (22) of all primary exhaust passages (19) have substantially the same cross-sectional area as one another, and / or the openings (22) of all secondary exhaust passages (21) have substantially the same cross-sectional area as one another, or the openings (22) of all exhaust passages (19, 21) have substantially the same cross-sectional area; The blowing device according to any one of claims 1 to 5.
7. The maximum diameter or width (D) of the opening (22) of any exhaust passage (19, 21) is 1.0 mm or less and 0.5 mm or more. The blowing device according to any one of claims 1 to 6.
8. The maximum diameter or width (D) of the opening (22) of any exhaust passage (19, 21) is not more than 0.9 mm and not less than 0.6 mm. The blowing device according to any one of claims 1 to 7.
9. The center-to-center distances between adjacent exhaust passages (19, 21) are substantially the same. The blowing device according to any one of claims 1 to 8.
10. the center-to-center distance between the adjacent exhaust passages (19, 21) is 3 to 5 times the maximum diameter or width (D) of the opening (22) of the widest exhaust passage among the adjacent exhaust passages (19, 21); The blowing device according to any one of claims 1 to 9.
11. The exhaust passages (19, 21) are arranged to be straight. The blowing device according to any one of claims 1 to 10.
12. the exhaust passages (19, 21) are arranged in a first group comprising a plurality of exhaust passages (19, 21) in a first line; at least one further group of at least two exhaust passages (19, 21) is arranged on a second line intersecting said first line; The blowing device according to any one of claims 1 to 11.
13. each of said further groups of exhaust passages comprises two exhaust passages (19, 21) arranged symmetrically between a pair of said exhaust passages (19, 21) of said first group of exhaust passages and symmetrically with respect to said first line; The blowing device of claim 12.
14. The first angle α is substantially 90°. The blowing device according to any one of claims 1 to 13.