WO2012072208A1

WO2012072208A1 - Impeller for accelerating blasting abrasive

Info

Publication number: WO2012072208A1
Application number: PCT/EP2011/005891
Authority: WO
Inventors: Jost Wadephul
Original assignee: Jost Wadephul
Priority date: 2010-12-03
Filing date: 2011-11-23
Publication date: 2012-06-07
Also published as: EP2646196A1; JP2013544194A; BR112013013686A2; US20130337727A1; DE102010053172B4; MX2013006143A; RU2013130106A; DE102010053172A1; CA2819421A1

Abstract

The invention relates to an impeller for feeding, into the shot-blasting wheel of a blasting installation, a blasting abrasive that is to be accelerated. Said impeller can be arranged in the central region of the shot-blasting wheel inside a distributor sleeve (12) with a discharge opening (22), and has, on at least one lateral disc (24), guiding elements (20a, 20b) for guiding the blasting abrasive towards the outside, each of said guiding elements (20a, 20b) having two lateral surfaces (26a, 26b) which, with guiding elements (20a, 20b) adjacent to the lateral surfaces (26a, 26b), form channels (18) through which the blasting abrasive can be discharged towards the outside. One or each of the guiding elements (20a, 20b) has an upper side (34a, 34b) that connects the outer ends (32a, 32b) of the two lateral surfaces (26a, 26b) of the guiding element (20a, 20b) to one another, and that has at least one section (38a, 38b, 40, 42 a-c) which is arranged in or above an imaginary, non-curved reference plane (36) connecting the lateral surfaces (26a, 26b) of the guiding element (20a, 20b) to one another, likewise at their outer ends.

Description

Impeller for accelerating abrasive Description

The invention relates to an impeller for feeding blasting agent to be accelerated in the blast wheel of a blasting machine, which can be arranged in the central region of the impeller within a metering sleeve having metering sleeve, and at least one side window guide members for guiding the blasting agent to the outside, wherein the guide elements respectively have two side surfaces which form with side surfaces of adjacent guide elements channels through which the blasting agent is discharged to the outside. The invention further relates to a blasting machine with a blast wheel having such an impeller.

For example, with blast machines equipped with blast wheels, surfaces of metallic rolled products are freed of scale and / or rust before the surface is given a protective coating by flinging a blasting medium, usually consisting of fine metal particles, against the surface. In such a blasting machine, preferably all particles of the blasting medium should move outward tangentially and as far as possible parallel to the blades of the rotating blasting wheel. However, this is often not the case. A considerable number of these particles strike the side windows and the blades and rebound off, like a ping-pong ball. This not only has a negative effect on the exit velocity of the blasting agent from the blast wheel, but also leads to an uneven distribution of the blasting agent on the surface to be cleaned. The impact of the abrasive particles on the parts of the impeller also subject to heavy wear.

CONFIRMATION COPY In order to improve the abrasive agent distribution and to reduce the wear of the centrifugal wheel, it is known to arrange a so-called impeller in the center of such a centrifugal wheel. Such a Impelier is subject to high wear. He usually sits in a coaxial surrounding him Zuteilhülse having a Zuteil- or discharge. During operation of the blasting machine blasting medium is guided in the axial direction in the center of the impeller. The impeller is set in rapid rotation and guides the blasting agent radially outward along the impeller channels formed by adjacent guide elements. In the space between the metering sleeve and Impelier the blasting agent enters a nearly circular path and runs in this area along this circular path. As a result of the rotation of the impeller, the blasting agent is finally transferred as tangentially as possible from the metering opening of the metering sleeve into the effective region of the blades of the blast wheel. This results in a smooth transition of the blasting agent in the blade area of the impeller over the entire width with subsequent uniform acceleration to the blade outlet. The impact of the blasting agent on the blades and side walls of the blast wheel is substantially suppressed.

It is an object of the invention to optimize such Impelier, especially in terms of its life.

This object is achieved by a Impelier with the features of claim 1.

Correspondingly, one or each guide element of an impeller according to the invention has in each case a radially outwardly pointing upper side which connects the outer ends of the two side faces of the guide element and which has at least one section which is either inside or above an imaginary one, said channel-limiting one. Side surfaces of the guide member is also arranged at the outer ends interconnecting, non-curved reference plane is arranged. According to the abovementioned first alternative of the invention, an upper side section arranged above the imaginary reference plane therefore protrudes radially outward beyond the reference plane. In the second alternative according to the invention, this section lies exactly within the imaginary reference plane.

As a result, both embodiments lead to a special shape of the space between the upper side of the respective guide element and the section of the dispensing sleeve surrounding the upper side of the opposite section. It has been found in experiments by the applicant that such a design of the guide elements of the impeller in operation of the blasting machine leads to a particularly low wear of the impeller and the impeller in the center of which the impeller is installed in the blasting plant state. In addition, the blasting agent distribution or the blasting pattern of the blasting system is particularly uniform.

In general, according to the invention, all the upper side sections or upper side areas forming the upper side will be arranged in and / or above the imaginary reference line. Accordingly, according to the invention, in one variant, all sections or regions of the upper side can be arranged above the reference plane. In another variant, all sections of the top can lie in the reference plane. Finally, in a third variant, at least one section of the upper side in the reference plane and at least one section of the upper side can at the same time be above the reference plane.

As far as the at least one section of the upper side arranged above the reference plane is concerned, it may generally be curved or uncrowned and inclined or not inclined to the reference plane.

Preferably, the guide element is formed symmetrically to a particular axially extending longitudinal center plane thereof. In addition, each guide element is preferably arranged on the impeller in such a way that the respective longitudinal middle planes each run essentially radially. In a preferred embodiment of the invention, the upper side of the guide element has, on both sides of the longitudinal center plane, at least one section which is arranged above the reference plane and which extends inclined to the imaginary reference plane. Each of the two sections runs in each case inclined relative to the imaginary reference plane such that the respective section, viewed in each case from the side surface adjacent to the respective section in the direction of the longitudinal center plane and with respect to the reference plane, has a positive gradient value. In other words, the height of the respective section with respect to the reference plane increases in each case with mental progression in the direction of the longitudinal center plane. In addition, each of these two sections preferably adjoins directly to the side surface of the guide element which is adjacent to it. The aforementioned two, extending on both sides of the longitudinal center plane, inclined portions of the upper side may be directly connected to each other or by at least one, at least partially curved connecting portion of the top. In a further embodiment of the invention, at least one non-curved top side section, which lies within the imaginary reference plane, is arranged on both sides of the longitudinal center plane in each case at least one, in particular adjacent to the respective side surface. In this case, these two sections in this embodiment, of course, pass unduly to the reference plane.

These upper side sections extending within the reference plane are also preferably connected to one another by a connecting section.

In a further embodiment of this embodiment, the connecting section preferably has connecting sections which are adjacent to the respective upper side section and respectively perpendicular or approximately perpendicular to these, arranged above the reference plane, and a connecting part which connects the aforementioned vertical connecting sections, parallel or approximately parallel to the top sections and also above the reference plane extending connecting section.

As regards the abovementioned, opposing side surfaces of adjacent guide members, which delimit the channels laterally between the guide elements, they preferably extend parallel or approximately parallel to one another at a distance from one another.

As far as the guide elements themselves are concerned, they may be of massive block construction, for example, or may be constructed of individual profile pieces or profile strips, for example. Here are several variants conceivable.

Further features of the invention will become apparent from the appended claims, the following description of a preferred embodiment and the accompanying drawings. It shows:

Fig. 1. a schematic sectional view of an impeller according to the invention. In Fig. 1, an impeller 10 is shown, which is arranged in the interior of a metering sleeve 12 of a blasting machine, not shown. In such a blasting system surfaces of components are acted upon by accelerated by the blasting abrasive. As a result, the component surfaces can be cleaned or freed from interfering surface layers, such as rust and scale or the like.

The impeller 10 is seated together with the surrounding sleeve 12 in the center of a blasting wheel, not shown, the blasting machine. The structure of such a blasting machine is known in principle in the prior art. A blast wheel driven by a motor used in such a blasting machine has a plurality of impeller blading blades distributed circumferentially along a side disk for accelerating the blasting means. The impeller 10 is first supplied to be accelerated blasting agent by a feed line, not shown. More precisely the blasting agent is passed from a blasting agent source or a blasting agent reservoir into the center 14 of the impeller. The impeller 10 is set in the operation of the blasting machine via a drive, not shown, about the rotation axis 16 in rotation. The blasting agent supplied to it centrally is guided outward by the impeller 10 along channels 18. The channels 18 are formed by side surface pairs 26a, 26b of adjacent guide members 20a, first embodiment, and 20b, second embodiment.

Through the channels 18, the blasting agent passes from radially further inward radially further outward and is accelerated on a circular path between the guide members 20a and 20b and the sleeve 12 in the direction of rotation of the impeller 10. About the discharge opening 22 in the sleeve 12, the blasting agent is finally discharged into the angular range of the blades of the impeller, not shown. In this case, the blasting agent emerges essentially tangentially from the discharge opening 22. This results in a smooth transition of the blasting agent in the radially outwardly arranged blade region of the impeller, not shown, over the entire width with subsequent uniform acceleration to the blade outlet. The impact of the blasting agent on the blades and side walls of the blast wheel is substantially suppressed. The bumpless transition of the blasting agent acting as a central accelerator 10 in the impeller not shown causes a uniform guidance of the blasting agent in the impeller. As a result, a uniform distribution of the blasting agent is achieved on the surface to be treated. In addition, the wear on the blast wheel and the expended to accelerate the blasting energy is reduced.

As already indicated above, the illustrated impeller 10 has two different embodiments 20a, 20b of guide elements. The various embodiments are shown together for the sake of simplicity in FIG. In fact, in operation, an impeller 10 according to the invention generally has only one type of guide elements, that is to say either the guide elements 20a or the guide elements 20b. Below are the same features the two embodiments 20a, 20b described together. Following this, the differences of the embodiments 20a, 20b are shown.

The guide members 20a, 20b are arranged on an end face of a first side window 24. A second side window, not shown, is arranged parallel to the first side window 24 in the axial direction at a distance, so that the guide elements 20a or 20b are positioned between the two side windows. It should be noted in this context that in the context of the invention, the guide members 20a and 20b can be made in principle as separate components, but of course also be integrally connected to the respective end face of the side windows.

The guide members 20a, 20b are raised relative to the front side plane of the side window 24, that is, they form elevations with respect to this plane. In principle, it is also conceivable to dispense with a second side window and to use only a side window.

The individual guide members 20a, 20b are distributed along an annular surface over the end face of the side window 24 in the circumferential direction. In the present case, the annular surface also forms the edge region of the front side of the side window 24.

Each guide element 20a, 20b is spaced apart from the two guide elements 20a and 20b which are respectively immediately adjacent to it on both sides in the circumferential direction.

The side surfaces 26a, 26b of the guide members 20a, 20b extend perpendicular to the plane of the drawing and thus perpendicular to the end face of the side window 24 in the axial direction. In addition, the illustrated side surfaces 26a, 26b in the cross-sectional view of FIG. 1 are directed to the dispensing sleeve 12. Accordingly, they run from radially further inward to radially further outward substantially radially or not at right angles to the radial. At their to the impeller center 14 and the impeller rotation axis 16 directed or at their radially inner ends 28a, 28b, the side surfaces 26a and 26b are connected to each other via a bottom 30. The underside 30 forms a plane, that is, non-curved connection plane.

At its two upper, radially outer ends 32a, 32b, the side surfaces 26a, 26b are interconnected via an upper side 34 (guide element 20a) or 34b (guide element 20b). The upper sides 34a and 34b also extend perpendicular to the end face of the side window 24, that is, in the axial direction.

Particularly important is the contour of the respective upper side 34a or 34b. Hereinafter, first, the contour 34a of the guide member 20a will be described. The entire upper side 34a extends above an imaginary reference plane 36, shown in dashed lines in FIG. 1, that is radially further outward than the latter. The imaginary reference plane 36 is an unbending junction plane which connects the two upper side ends 32a and 32b of the side surfaces 26a, 26b by the shortest route.

The upper side 34a is, like the entire guide element 20a, formed symmetrically to an axially extending longitudinal center plane 21. It has on both sides of the longitudinal center plane 21 on the side surface ends 32a, 32b respectively adjacent (non-curved) sections 38a and 38b. These non-curved portions 38a, 38b extend above the imaginary reference plane 36. In addition, the non-curved portions relative to the reference plane 36 are inclined at an angle a. The inclination in this case is such that the pitch, for example, of the non-curved portion 38a relative to the reference plane 36 increases, ie, is positive. Here, the viewing direction is defined by the direction from the side surface end 32a adjacent to the non-curved portion 38a toward the longitudinal center plane 21. In other words, the height of the non-curved portion 38a increases with respect to the reference plane 36 as viewed in the mentioned direction. Similarly, the pitch of section 38b increases, also referred to to the reference plane 36, but viewed in the opposite direction, namely from the side face end 32b adjacent to the non-curved portion 38b, to the longitudinal center plane 21. The two non-curved portions 38a, 38b are further connected to each other by a connecting portion 40. This is convex.

Overall, the illustrated upper side contour of the guide member 20a causes the space between the upper side 34a and the sleeve 34a opposite the upper side 34a starting from the-depending on the direction of impeller - respectively leading, outer side surface 38a or 38b initially narrowed with minimal space volume at the connecting portion 40 and then widens again to the trailing side surface end.

The second embodiment of a guide member 20b differs from the guide member 20a in the contour of the top 34b. Unlike the non-curved portions 38a, 38b of the guide member 20a, the non-curved portions 38a, 38b of the guide member 20b are not inclined to the reference plane 36 but lie exactly within the reference plane 36.

In addition, the connecting section 40 connecting the two non-curved sections 38a, 38b is designed as a projection: the two side sections 38a, 38b extending perpendicularly to the two top sections 38a, 38b lying in the reference plane 36 adjoin the section sections 42a, 42b, respectively, which are arranged above the reference plane 36, however Connecting portion 40 at. A subconnecting section 42c, which in turn is likewise arranged above the reference plane 36 and runs perpendicular to these subconnecting sections 42a, 42b and parallel to the sections 38a, 38b, in turn connects the partial connecting sections 42a, 42b to one another.

Attempts of the applicant have shown that guide elements with a basic structure as shown in the context of this application and claimed among other things lead to particularly long service life of the respective impeller to particularly long service life of the impeller as well as a particularly uniform blasting media image.

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LIST OF REFERENCE NUMBERS

10 impellers

12 distribution sleeve

14 impeller center

16 rotation axis

18 channel

20a guide element

20b guide organ

21 longitudinal center plane

22 discharge opening 24 side window 26a side surface

26b side surface

28a side surface end

28b side surface end

30 bottom

32a side surface end

32b side surface end

34a top

34b top

36 reference plane

38a section

38b section

40 connecting section

42a subsection

42b subsection

42c subsection

Claims

claims

1. impeller for feeding accelerating blasting medium into the blast wheel of a blasting machine, which can be arranged in the central area of the blast wheel within a dispensing opening (22) having a dispensing sleeve (12), and on at least one side window (24) guide members (20a, 20b) for guiding the blasting agent to the outside, wherein the guide members (20a, 20b) each have two side surfaces (26a, 26b) which form side walls (26a, 26b) of adjacent guide members (20a, 20b) channels (18) through which the Blasting agent is discharged to the outside, characterized in that one or each guide member (20a, 20b) each have an upper side (34a, 34b), the outer ends (32a, 32b) of the two side surfaces (26a, 26b) of the guide element ( 20a, 20b), and the at least one portion (38a, 38b, 40, 42 ac), in or above an imaginary, the side surfaces (26a, 26b) of the guide member (20a, 20b) also at their OUTER ends interconnecting, non-curved reference plane (36) is arranged.

2. impeller according to claim 1, characterized in that the guide member (20a, 20b) symmetrical to a longitudinal center plane (21) of the guide member (20a, 20b) is formed.

3. Impeller according to claim 2, characterized in that the upper side (34a, 34b) of the guide element (20a, 20b) on both sides of the longitudinal center plane (21) each have at least one, above the imaginary reference plane (36) arranged, non-curved portion (38a , 38b, 40, 42a-c).

4. impeller according to claim 2 or 3, characterized in that the upper side (34 a) of the guide element (20 a) on both sides of the longitudinal center plane (21) each at least one, in particular to the respective side surface (26 a, 26 b) adjacent, inclined to the imaginary Reference plane (36) extending Section (38a, 38b), wherein the inclination is formed such that on the reference plane (36) related slope of the portion (38a, 38b), each viewed in the direction of the longitudinal center plane (21) increases.

5. impeller according to claim 4, characterized in that the two, on both sides of the longitudinal center plane (21) extending portions (38 a, 38 b) of the upper side (34 a) are directly connected to each other or by at least one at least partially curved connecting portion (40) the top (34a).

6. impeller according to claim 4 or 5, characterized in that the two inclined portions (38 a, 38 b) are not curved.

7. impeller according to one or more of the preceding claims 2- 6, characterized in that arranged on both sides of the longitudinal center plane (21) at least one, in particular to the respective side surface (26a, 26b) adjacent, non-curved top portion (38a, 38b) is located in the imaginary reference plane (36).

8. Impeller according to claim 7, characterized in that in the imaginary reference plane (36), on both sides of the longitudinal center plane (21) arranged upper side portions (38 a, 38 b) are interconnected by at least one connecting portion (40).

9. An impeller according to claim 8, characterized in that the two upper side portions (38a, 38b) are interconnected by two on both sides of the longitudinal center plane, to the respective upper side portion (38a, 38b) adjacent and perpendicular or approximately perpendicular to these extending connecting portions ( 42a, 42b) and one of the aforementioned vertical connecting portions (42a, 42b) interconnecting, parallel or approximately parallel to the upper side portions (38a, 38b) extending connecting portion (42c).

10. impeller according to one or more of the preceding claims, characterized in that the channel-limiting side surfaces (26a, 26b) of adjacent guide members (20a, 20b) parallel or approximately parallel to each other at a distance.

11. Impeller according to one or more of the preceding claims, characterized in that all sections (38a, 38b, 40, 42a-c) of the upper side (34a, 34b) in and / or above the imaginary, the side surfaces (26a, 26b) connecting reference plane (36) are arranged.

12. blasting machine with a blast wheel, an arranged in the central region of the impeller Zuteilhülse (12) with discharge opening (22) and in the interior of the metering sleeve 12 arranged impeller (10) having the features of claim 1.

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