Cellular wheel sluice for granulate bulk product

Abstract

A cellular wheel sluice for granulate bulk product has a housing in which a cellular wheel is rotatably mounted. The housing has an inlet duct for the bulk product. At least two raised granulate roofs are arranged at the inlet duct. A granulate groove is arranged respectively at the transition between two granulate roofs and/or at the transition between one granulate roof and an inlet edge. The two granulate grooves in each case run together at an intersection point in the rotation direction of the cellular wheel.

Claims

1. A cellular wheel sluice for granulate bulk product, with a housing in which a cellular wheel is rotatably mounted, wherein the housing has an inlet duct for the bulk product, wherein at least two raised granulate roofs are arranged at the inlet duct, wherein a granulate groove is arranged respectively at least one of at the transition between two granulate roofs and at the transition between one granulate roof and an inlet edge, wherein two granulate grooves in each case run together at an intersection point in the rotation direction of the cellular wheel.

2. The cellular wheel sluice according to claim 1, wherein a displacement angle enclosed between one of the granulate grooves and a cellular wheel web is constant at least in portions irrespective of the rotary position of the cellular wheel.

3. The cellular wheel sluice according to claim 1, wherein a displacement angle enclosed between one of the granulate grooves and a cellular wheel web increases at least in portions in the rotation direction of the cellular wheel.

4. The cellular wheel sluice according to claim 3, wherein for the displacement angle : 3090.

5. The cellular wheel sluice according to claim 1, wherein each granulate groove has a constant cross-sectional area along the groove course.

6. The cellular wheel sluice according to claim 1, wherein each granulate groove has an opening angle oriented relative to an interior of the housing, wherein 80120.

7. The cellular wheel sluice according to claim 1, wherein each granulate groove has a demoulding chamfer facing an interior of the housing.

8. The cellular wheel sluice according to claim 1, wherein deflection edges of the granulate roofs have the same lengths l.

9. The cellular wheel sluice according to claim 8, wherein deflection edges of the granulate roofs are evenly distributed in a transverse direction which is oriented parallel to the rotation axis of the cellular wheel.

10. The cellular wheel sluice according to claim 1, wherein a lateral distance A of deflection edges of the granulate roofs from the inlet edge is greater than the length l of the deflection edges.

11. The cellular wheel sluice according to claim 1, wherein each granulate roof is tilted continuously relative to a vertical plane.

12. The cellular wheel sluice according to claim 11, wherein each granulate roof extends up to a cylinder bore of the housing.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows a top view of a sluice according to the invention without cellular wheel, looking into the inlet duct,

(2) FIG. 2 shows a sectional depiction along section line II-II in FIG. 1,

(3) FIG. 3 shows an enlarged depiction of detail III in FIG. 2,

(4) FIG. 4 shows a sectional depiction along section line IV-IV in FIG. 2,

(5) FIG. 5 shows a side view of a cellular wheel sluice according to a further embodiment, with various view planes marked,

(6) FIG. 6 shows a depiction of the housing interior of the cellular wheel sluice according to FIG. 5, according to view VI-VI,

(7) FIG. 7 shows a depiction corresponding to FIG. 6, according to view VII-VII in FIG. 5,

(8) FIG. 8 shows a depiction corresponding to FIG. 6, according to view VIII-VIII in FIG. 5,

(9) FIG. 9 shows a view corresponding to FIG. 4 of a cellular wheel sluice according to a further embodiment,

(10) FIG. 10 shows a depiction corresponding to FIG. 3 of a granulate groove of a cellular wheel sluice according to a further exemplary embodiment,

(11) FIG. 11 shows a detail view corresponding to FIG. 10 of a granulate groove of the cellular wheel sluice according to a further embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(12) A cellular wheel sluice shown in FIGS. 1 to 8 and designated as a whole as 1 serves for metered delivery of granulate bulk product, in particular plastic granulate.

(13) The cellular wheel sluice 1 comprises a housing 2 with a cylindrical bore 3 in which a cellular wheel 4 is arranged coaxially so that it can be driven in rotation about a rotation axis 5. The cylinder bore 3 forms the interior of the housing 2.

(14) The cellular wheel 4 has a cellular wheel shaft 6 and several cellular wheel webs 7 which are arranged on the cellular wheel shaft 6 and oriented radially relative to the rotation axis 5. The cellular wheel webs 7 are arranged around the rotation axis 5 and equally spaced apart from each other in the rotation direction 8. A cellular wheel chamber 10, into which the granulate bulk product is metered for delivery, is delimited between the cellular wheel shaft 6, two adjacent cellular wheel webs 7, and an inner casing surface 9 of the cylinder bore 3.

(15) According to the exemplary embodiment shown, the cellular wheel 4 has twelve cellular wheel webs 7, so that twelve cellular wheel chambers 10 are formed. The number of cellular wheel webs 7 may be greater or smaller depending on the application of the cellular wheel 4, in order to set a finer or coarser distribution of the cellular wheel chambers 10.

(16) On the end faces along the rotation axis 5, the housing 2 may be closed tightly by a respective side cover (not shown). For this, the housing 2 has a connecting flange 12 arranged on each end face and integrated in the housing 2. Several fixing bores (not shown) are provided at the connecting or side flange 12, so that the housing cover can be mounted releasably and tightly on the side flange 12 by means of fixing screws. For this, a seal, in particular an O-ring or a flat seal, may be arranged between the side flange 12 and the side cover.

(17) On the outside of the housing 2, a leakage air connector 17 is arranged which is connected via a leakage air channel 28 to the cylinder bore 3. The leakage air channel 28 may in regions have two strands running parallel to each other, as shown in FIG. 4. The leakage air channel 28 may, additionally or alternatively, have fittings (not shown) for sound reduction.

(18) The housing 2 comprises an inlet duct 14 via which the bulk product is supplied to the cellular wheel sluice 1, in particular the cylinder bore 3, with the cellular wheel 4. In the installation position of the cellular wheel sluice 1 shown in FIGS. 2 and 7, the inlet duct 14 is arranged at the top so that the bulk product supplied is conveyed automatically under gravity into the cylinder bore 3. The inlet duct 14 has an inlet chamfer 15, along which the granulate bulk product flows into the cylinder bore 3. The inlet duct 14 is connected to the cylinder bore 3 via an inlet opening 16. The inlet surface 16 has a width B oriented parallel to the rotation axis 5. In a projection of the inlet opening 16 in a horizontal plane according to FIG. 1, the inlet opening 16 has a length L oriented perpendicularly to the width B.

(19) At its upper end, the inlet duct 14 has a connecting flange 18 which is designed correspondingly to the connecting flanges 12 arranged on the end faces. According to the exemplary embodiment shown, sixteen fixing bores 13 are arranged at the connecting flange 18 of the inlet duct 14.

(20) Three nose-like granulate roofs 19 are arranged at the inlet duct 14, in particular along the inlet chamfer 15. The granulate roofs 19 are designed raised relative to the inlet chamfer 15. The granulate roofs 19 create an enlargement of the surface area of the inlet chamfer 15 in the inlet duct 14. The granulate roofs 19 are arranged in the manner of an equilateral saddle roof at the inlet chamfer 15. The granulate roofs 19 extend like dormers away from the inlet chamfer 15. Each granulate roof 19 has a ridge 20 and two longitudinal faces 21 which are arranged tilted by a slope angle relative to a vertical plane, oriented in particular perpendicularly to the rotation axis 5. The free edges of the longitudinal faces 21 which are arranged facing away from the inlet chamfer 15 are described as deflection edges 22. The deflection edge 22 is also called the inlet edge.

(21) The granulate roofs 19 extend at the inlet chamfer 15 in the inlet duct 14 up to the cellular wheel bore 3, as shown in particular in FIG. 2 and in detail in FIG. 3. The granulate roofs 19 each have the ridge 20 as the front edge, which runs into a lower front tip 33. The tip 33 faces the cylinder bore 3 and constitutes the transition between the inlet chamfer 15 with the granulate roof 19 to the cylinder bore 3.

(22) The granulate roofs 19 are arranged next to each other in the width direction, i.e. in a direction parallel to the rotation axis 5. The granulate roofs 19 are arranged at the inlet chamfer 15 such that the respective ridge 20 is oriented transversely and in particular perpendicular to the rotation axis 5.

(23) A first granulate groove 23 is formed in a respective transitional region between two adjacent granulate roofs 19. The first granulate groove 23 is in particular arranged as a groove-like depression at a virtual abutment edge of the respective longitudinal faces 21 of adjacent granulate roofs 19. At a respective outside of the outermost granulate roofs 19, i.e. in a transitional region between the outermost granulate roofs 19 and an inner delimiting wall of the inlet duct 14, a second granulate groove 24 is arranged which is designed substantially identically to the first granulate groove 23. The delimiting wall has an upper delimiting edge 25 facing the inlet duct 14. The delimiting edge 25 forms an inlet edge.

(24) The granulate grooves 23, 24 are each designed as a groove-like depression in the casing surface 9 of the cylinder bore 3. The granulate grooves 23, 24 extend in the rotation direction 8 of the cellular wheel 4. Two granulate grooves 23, 24 in each case run together at an intersection point 26. The intersection point 26 should not be regarded as a point in the geometric sense. It is the connecting site between two grooves, in particular a connecting region, for example a sectional plane and/or an edge, as shown in particular in FIG. 4.

(25) Because the granulate grooves 23, 24 run together in pairs at an intersection point 26, the number of intersection points, namely two, is reduced in particular relative to the total number of granulate roofs 19, namely three. The cellular wheel sluice 1 optimises the number of granulate roofs 19 relative to that of intersection points 26.

(26) According to the exemplary embodiment shown, in the region of the inlet duct, the surface area is enlarged by the granulate roofs 19 by at least 20%, in particular by at least 25% and in particular at least 30% in comparison with a comparable cellular wheel sluice with just one granulate roof.

(27) According to the exemplary embodiment shown, all granulate roofs 19 are configured identically. The deflection edges 22 of a granulate roof 19 each have the same lengths l. The deflection edges 22 of the different granulate roofs 19 also have the same lengths l. In particular, the granulate roofs 19 are evenly distributed along the rotation axis 5. This means that the deflection edges 22, which are arranged from the inlet duct 14 to the respective granulate roofs 19 arranged on the outside, have the same length l as the lengths of the deflection edges 22 of the actual granulate roofs 19. The granulate roofs 19 are evenly distributed along the rotation axis 5. With this design, the granulate roofs 19 are designed comparatively larger, i.e. have a larger roof area. Accordingly, the granulate grooves 23, 24 are designed comparatively longer, so that the chopping behaviour of the cellular wheel sluice 1 is further improved. The risk of granulate grains being crushed or cut on entry into the cellular wheel sluice 1, in particular into the cylinder bore 3, is reduced.

(28) The sectional depiction according to FIG. 3 shows the intersection point 26 with two granulate grooves 23, 24 running together. In this depiction, the cross-sectional area of the granulate groove 23, 24 can be seen. The cross-sectional shape of the granulate groove 23, 24 is substantially rectangular, with a groove depth n.sub.t and a groove width n.sub.b. According to the exemplary embodiment shown, the groove width n.sub.b is greater than the groove depth n.sub.t, in particular n.sub.b1.2.Math.n.sub.t, in particular n.sub.b1.5.Math.n.sub.t. The cross-sectional area of the granulate groove 23, 24 is in particular dimensioned such that a granulate grain of mean granulate size lies contactlessly, i.e. without having to bear on the side faces of the granulate groove 23, 24 or on a cellular wheel web 7 which passes by the opening of the granulate groove 23, 24.

(29) In particular, the minimum clear width of the granulate groove 23, 24, which, according to the exemplary embodiment shown, corresponds to the Groove depth n.sub.t, is greater than the largest particle diameter of the granulate grains. This guarantees free transport of the granulate grains along the granulate groove 23, 24.

(30) According to the exemplary embodiment shown, the granulate groove 23, 24 has a constant cross-sectional area along the groove course.

(31) The granulate groove 23, 24 is arranged, in particular at the intersection point 26, with an opening angle relative to the cylinder bore 3 of the housing 2, wherein the opening angle is less than or equal to 120. It is advantageous if the opening angle is between 80 and 120, in particular between 90 and 110.

(32) The opening angle is defined by the side edge 29 of the granulate groove 23, 24 at the rear in the rotation direction 8, and by the tangent 30 at the casing surface of the cylinder bore 3 at the intersection point with the rear side edge 29.

(33) On the underside of the housing 2, the cellular wheel sluice 1 has an outlet duct 31. The inlet duct 14 and the outlet duct 31 are arranged opposite each other relative to the rotation axis 5. Via the outlet duct 31, the bulk product conveyed and metered by means of the cellular wheel 4 can be output from the cellular wheel sluice 1. On the end face at the bottom at the outlet duct 31, the housing 2 has a further connecting flange 18 for connection of the cellular wheel sluice 1 to delivery components and/or lines, which flange is designed substantially identically to the connecting flange 18 at the inlet duct 14.

(34) With reference to FIGS. 5 to 8, a displacement angle and its function are now explained in more detail. FIGS. 6 to 8 each show a view from the centre, i.e. from the rotation axis 5, of the cylinder bore 3 onto an underside of the inlet chamfer 15 with the granulate roofs 19. The drawings also each show a cellular wheel web 7. The essential feature of the depictions in FIGS. 6 to 8 is that the view is not vertical, but is a view in the radial direction relative to the rotation axis 5. The depictions in FIGS. 6 to 8 thus take into account the respective rotary position of the cellular wheel 4 or cellular wheel web 7 relative to the granulate grooves 23, 24. The displacement angle is enclosed between the granulate groove 23, 24 and the cellular wheel web 7.

(35) It has been found that it is advantageous if the displacement angle is greater than or equal to 30. It is particularly advantageous if the displacement angle is greater than or equal to 30 irrespective of the rotary position of the cellular wheel 4. According to the exemplary embodiment shown, the displacement angle is 45 irrespective of the rotary position of the cellular wheel. The displacement angle may also be greater than or less than 45.

(36) In particular, it has been found that it is not necessary for the displacement angle to have a constant course in a top view onto the granulate groove 23, 24 and/or the deflection edge 22. In particular, the displacement angle may increase continuously in the granulate groove 23, 24 up to the intersection point 26.

(37) In particular, the displacement angle is similar and in particular identical for all deflection edges 22. A similar displacement angle means that angular deviations between different displacement angles do not exceed 5, in particular 3 and in particular 1. This means that, in the inlet duct 14, all deflection edges 22 are defined similarly, in particular identically. The displacement edges 22 in particular run in the rotation direction 8 of the cellular wheel 4.

(38) It is therefore possible to reduce the displacement angle in the cellular wheel sluice 1 shown. By reducing the displacement angle , in particular to less than 45, the inlet opening is enlarged. In this way, the cellular wheel sluice 1 may be operated with an increased throughput, i.e. with higher capacity.

(39) A centre distance M of the front tips 33 of the inlet chamfers 15 from the rotation axis 5 is comparatively large, according to this exemplary embodiment, in relation to a cellular wheel sluice known from U.S. Pat. No. 5,129,554 with just one granulate roof. The centre distance M is smaller than a radius r of the circular bore of the inlet duct 14 or outlet duct 31. In particular: M<r, in particular M<0.8.Math.r, in particular M<0.6.Math.r, and in particular M<0.5.Math.r.

(40) FIG. 9 shows a further embodiment of a cellular wheel sluice 1. Components which correspond to those already explained above with reference to FIGS. 1 to 8 carry the same reference signs and are not discussed again in detail.

(41) In the cellular wheel sluice 1, the granulate roofs 32 are designed comparatively smaller. This means that the length l of the deflection edges 22 of the granulate roofs 32 is smaller than in the previous exemplary embodiment. Also, a lateral distance A of the deflection edges 22 of the granulate roofs 32 from the side inlet edge 25 is greater than the respective length l of the deflection edges 22. In particular: A1.5.Math.l, in particular A2.Math.l and in particular A2.5.Math.l.

(42) In the exemplary embodiment shown, the centre distance M of the front tips 33 from the rotation axis 5 is at least 0.45.Math.r. In particular: M>0.48.Math.r, in particular M0.5.Math.r and in particular M0.525.Math.r.

(43) In this embodiment, the inlet opening 16 is cleared to a larger proportion. This means that the free through-flow area of the inlet opening 16 in this exemplary embodiment is larger. The conduction capacity of this cellular wheel sluice is increased.

(44) According to the exemplary embodiment shown in FIG. 10, the granulate groove 35 has a substantially rounded contour. Also, the granulate groove 35 has a demoulding chamfer c with which the upper groove edge 36, at the front of the rotation direction 8, is additionally opened towards the cylinder bore 3. The demoulding chamfer, according to the exemplary embodiment shown, is approximately 1. By designing the granulate groove 35 with the demoulding chamfer e, the housing 2 can be removed directly from the mould in the demoulding direction 37 during production by casting. In this way, a further core part for the casting process may be omitted. Casting production of the housing 2 with the granulate groove 35 with the demoulding chamfer is simplified. In particular, the demoulding chamfer c is the angle formed between the front edge 36 of the granulate groove 35 and the demoulding direction 37.

(45) FIG. 11 shows a further embodiment of the granulate groove 35 which corresponds substantially to the embodiment in FIG. 3, wherein the groove depth n.sub.t is enlarged so that the granulate groove 35 has approximately a square cross-sectional area.

(46) The opening angle is selected correspondingly to the exemplary embodiment in FIG. 3.