Dimensionally stable ring element for a heat exchanger casing

Abstract

A dimensionally stable ring element (1, 2) for a heat exchanger casing (3) includes: a cylindrical sleeve (10, 20) having a cylinder axis (102, 202), a first end (104, 204) and a second end (106, 206) remote from the first end, and having an inner wall (108, 208), a dividing wall (11, 21) which projects inwards from the inner wall (108, 208) of the sleeve (10, 20) and extends helically around the cylinder axis (102, 202) along the inner wall (108, 208) from the first end (104, 204) of the sleeve (10, 20) to the second end (106, 206) of the sleeve (10, 20). At its first end (104, 204) the sleeve (10, 20) includes a projection (109, 116, 209, 216) extending parallel to the cylinder axis (102, 202), which projection is arranged in a predetermined circumferential position on the sleeve (10, 20).

Claims

1. An agitator ball mill, comprising: a grinding container having a container wall that is cylindrical, a heat exchanger casing having a plurality of ring elements, each ring element of the plurality of ring elements being dimensionally stable and having: a cylindrical sleeve having a cylinder axis, a first end and a second end remote from the first end, and having an inner wall, and a dividing wall which projects inwards from the inner wall of the sleeve and extends helically around the cylinder axis along the inner wall from the first end of the sleeve to the second end of the sleeve, wherein the sleeve, at a first end of the sleeve, comprises a projection extending parallel to the cylinder axis, which projection is arranged in a predetermined circumferential position on the sleeve, and wherein the sleeve, at a second end of the sleeve, comprises a recess extending parallel to the cylinder axis, which recess has a shape complementary to the projection and is arranged on the sleeve in the same predetermined circumferential position as the projection, wherein the ring elements of the plurality of ring elements are arranged one after the other in a row in the direction of the cylinder axis, with the projection of a ring element of the plurality of ring elements that is arranged subsequently in the row interlockingly engaging in the recess of a respective preceding ring element of the plurality of ring elements arranged in the row, wherein the heat exchanger casing is arranged around the container wall, so that a helical channel is formed by the dividing walls of the ring elements of the heat exchanger casing extending helically around the cylinder axis and by the container wall, and an inlet and an outlet for a heat transfer medium, the inlet being connected to a first end of the helical channel and the outlet being connected to a second end of the helical channel of the heat exchanger casing, which second end is remote from the first end.

2. The agitator ball mill of claim 1, further comprising a cylindrical outer cover which encompasses the heat exchanger casing.

3. The agitator ball mill of claim 1 wherein: the dividing wall of each ring element of the plurality of ring elements of the heat exchanger casing has a flexible sealing lip at its end remote from the inner wall of the sleeve, the flexible sealing lip has an inner edge having an internal diameter and the container wall of the grinding container has an external diameter, the internal diameter of the sealing lip being smaller than the external diameter of the container wall of the grinding container, so that the flexible sealing lip is bent and rests against the container wall of the grinding container.

4. The agitator ball mill of claim 1 wherein: the dividing wall of each ring element of the plurality of ring elements of the heat exchanger casing is in the form of a dimensionally stable bead running helically around the cylinder axis, which bead projects inwards from the inner wall of the sleeve, the dimensionally stable bead has an inner edge having an internal diameter and the container wall of the grinding container has an external diameter, the internal diameter of the bead being larger than the external diameter of the container wall of the grinding container, so that a gap is formed between the inner edge of the bead and the container wall of the grinding container.

5. The agitator ball mill of claim 1, wherein the projection at the first end of the sleeve has a tooth having a tooth length and a tooth width, and wherein the recess at the second end of the sleeve has a notch having a notch depth and a notch width, the tooth having a shape complementary to the notch, and the tooth length corresponding to the notch depth and the tooth width corresponding to the notch width.

6. The agitator ball mill of claim 1, wherein the projection at the first end of the sleeve comprises an overhang extending along a circumference of the sleeve, which overhang has an overhang length in the direction of the circumference of the sleeve and an overhang width in the direction of the cylinder axis, and wherein the recess at the second end of the sleeve comprises a cutaway extending in the direction of the circumference of the sleeve, which cutaway has a cutaway length in the direction of the circumference of the sleeve and a cutaway depth in the direction of the cylinder axis, the overhang having a shape complementary to the cutaway, and the overhang length corresponding to the cutaway length and the overhang width corresponding to the cutaway depth.

7. The agitator ball mill of claim 6, wherein the dividing wall extends helically around the cylinder axis from the overhang at the first end of the sleeve to the cutaway at the second end of the sleeve, and wherein the dividing wall has a dividing wall width extending parallel to the cylinder axis, which dividing wall width is smaller than or equal to the overhang width.

8. The agitator ball mill of claim 1, wherein the dividing wall has a flexible sealing lip at an end of the dividing wall remote from the inner wall of the sleeve.

9. The agitator ball mill of claim 8, wherein the sleeve is made from a first material having a first modulus of elasticity and the dividing wall is made from a second material having a second modulus of elasticity, the first modulus of elasticity of the material of the sleeve being greater than the second modulus of elasticity of the material of the dividing wall.

10. The agitator ball mill of claim 9, wherein the sleeve made from the first material with the dividing wall made from the second material is manufactured by a two-component injection-moulding process.

11. The agitator ball mill of claim 1, wherein the dividing wall is in the form of a dimensionally stable bead running helically around the cylinder axis, which bead projects inwards from the inner wall of the sleeve.

12. The agitator ball mill of claim 11, wherein the sleeve and the dividing wall are manufactured from the same material by a one-component injection-moulding process.

Description

(1) The invention is described in greater detail below on the basis of exemplary embodiments and with reference to the accompanying drawings, wherein, in partly diagrammatic form:

(2) FIG. 1 shows a longitudinal section through an agitator ball mill according to the invention having a heat exchanger casing according to the invention with dimensionally stable ring elements according to the invention;

(3) FIG. 2 is a perspective view of a first exemplary embodiment of a dimensionally stable ring element according to the invention;

(4) FIG. 3 is a side view of the dimensionally stable ring element from FIG. 2;

(5) FIG. 4 shows a longitudinal section through the dimensionally stable ring element from FIG. 2;

(6) FIG. 5 is an enlarged view of the detail V from FIG. 4;

(7) FIG. 6 is a perspective view of the heat exchanger casing with a cylindrical outer cover;

(8) FIG. 7 shows a longitudinal section through the heat exchanger casing with the cylindrical outer cover from FIG. 6 on a grinding container;

(9) FIG. 8 is an enlarged view of the detail VIII from FIG. 7;

(10) FIG. 9 shows a longitudinal section through a second exemplary embodiment of the dimensionally stable ring element according to the invention;

(11) FIG. 10 is a side view of the second exemplary embodiment of the dimensionally stable ring element according to the invention, and

(12) FIG. 11 shows a longitudinal section through a heat exchanger casing of the second exemplary embodiment of the dimensionally stable ring element according to the invention on a grinding container.

(13) The following considerations apply in respect of the description which follows: where, for the purpose of clarity of the drawings, reference symbols are included in a Figure but are not mentioned in the directly associated part of the description, reference should be made to the explanation of those reference symbols in the preceding or subsequent parts of the description. Conversely, to avoid over-complication of the drawings, reference symbols that are less relevant for immediate understanding are not included in all Figures. In that case, reference should be made to the other Figures.

(14) As can be seen in FIG. 1, an exemplary embodiment of an agitator ball mill 4 according to the invention comprises a grinding container 5, in which there is arranged an agitator for grinding the material to be ground. The agitator can be connected via a belt drive to a motor driving the agitator. The grinding container has a material input for the material to be ground and a material output for the ground material. The agitator ball mill 4 also comprises a heat exchanger casing 3, which is arranged around a cylindrical container wall 50 of the grinding container 5. The heat exchanger casing 3 comprises a plurality of dimensionally stable ring elements 1 (see FIG. 2-5) or a plurality of dimensionally stable ring elements 2 (see FIGS. 9 and 10), which are arranged one after the other in a row in the direction of a cylinder axis 102 (see, for example, FIG. 3) or in the direction of a cylinder axis 202 (see, for example, FIG. 10), respectively. The heat exchanger casing 3 comprising the plurality of ring elements 1 or the plurality of ring elements 2 is shown in FIG. 6 to 8 and FIG. 11 and is described in greater detail hereinbelow. In addition, the agitator ball mill 4 has an inlet 40 and an outlet 42 for a heat transfer medium, for example water. The inlet 40 and the outlet 42 is described in greater detail hereinbelow in connection with the heat exchanger casing 3.

(15) FIG. 2, FIG. 3, FIG. 4 and FIG. 5 show a first exemplary embodiment of a dimensionally stable ring element 1 used in the heat exchanger casing 3 of the agitator ball mill 4. Such a dimensionally stable ring element 1 comprises a cylindrical sleeve 10 having the cylinder axis 102 and a first end 104 as well as a second end 106 remote from the first end 104. The dimensionally stable ring element 1 further comprises a dividing wall 11, which projects inwards from an inner wall 108 of the cylindrical sleeve 10 and extends helically around the cylinder axis 102 along the inner wall 108 from the first end 104 to the second end 106. The cylindrical sleeve 10 can be made, for example, from polyamide, which has a first modulus of elasticity. Good dimensional stability of the sleeve 10 can be achieved if fibre-reinforced, for example glass-fibre-reinforced, polyamide is chosen as material for the cylindrical sleeve 10.

(16) At its first end 104 the cylindrical sleeve 10 has a tooth 109 extending parallel to the cylinder axis 102, as can be seen especially clearly in FIG. 4. Furthermore, at its second end 106 the cylindrical sleeve 10 has a notch 113 extending parallel to the cylinder axis 102 and complementary in shape to the tooth 109. The tooth 109 has a tooth length 112 and a tooth width 110, and the notch has a notch depth 115 corresponding to the tooth length 112 and a notch width 114 corresponding to the tooth width 110.

(17) Furthermore, the cylindrical sleeve 10 has, at the first end 104, an overhang 116 extending along the circumference of the sleeve, as can readily been seen in FIG. 3. The cylindrical sleeve 10 also has, at its second end 106, a cutaway 119 complementary in shape to the overhang, which cutaway is indicated in dashed lines in FIG. 3. The overhang 116 has an overhang length 118 (see FIG. 2) in the direction of the circumference of the sleeve and an overhang width 117 in the direction of the cylinder axis 102 (see FIG. 3). The cutaway 119 has a cutaway length 122 (see FIG. 2) corresponding to the overhang length 118 and a cutaway depth 120 (see FIG. 3) corresponding to the overhang width 117.

(18) FIG. 5 shows the detail V from FIG. 4 on a slightly enlarged scale, so that the dividing wall 11 of the dimensionally stable ring element 1 can be seen more clearly. The dividing wall 11 can extend helically around the cylinder axis 102 from the overhang 116 at the first end 104 of the sleeve 10 to the cutaway 119 at the second end 106 of the sleeve 10. The dividing wall 11 has a dividing wall width 126, which is smaller than or equal to the overhang width 117 of the overhang 116. Furthermore, the dividing wall 11 has a flexible sealing lip 128 at its end remote from the inner wall 108 of the cylindrical sleeve 10, as can also be seen in FIG. 8.

(19) The flexible sealing lip 128 has an inner edge 130 which defines an internal diameter 132 (see FIG. 4) of the dividing wall 11 which runs helically around the cylinder axis 102. In the exemplary embodiment shown, that internal diameter 132 is smaller than the external diameter 500 of the cylindrical container wall 50 of the grinding container 5. That difference in diameter has the result that when the dimensionally stable ring element 1 is arranged around the container wall 50, the flexible sealing lip 128 rests in a bent state against the container wall 50 of the grinding container 5, as can be seen in FIG. 8.

(20) The dividing wall 11 can be made from a thermoplastic elastomer which has a second modulus of elasticity, the second modulus of elasticity of the thermoplastic elastomer of the dividing wall 11 being smaller than the first modulus of elasticity of the polyamide of the sleeve 10. The sleeve 10 and the dividing wall 11 can have been made, for example, by a two-component injection-moulding process.

(21) In such a two-component injection-moulding process, in a first step the sleeve 10 is injection-moulded from polyamide and then the dividing wall 11 is injection-moulded in a second step. Various measures can be taken to ensure that the dividing wall 11 is firmly seated in the sleeve 10. For example, the sleeve 10 can have a region of contact with the dividing wall 11, which region, after the injection-moulding of the dividing wall 11, forms an insoluble interlocking connection with the dividing wall 11.

(22) A heat exchanger casing 3 is formed by a plurality of dimensionally stable ring elements 1 which are arranged one after the other in a row in the direction of the cylinder axis 102. This allows the tooth 109 and the overhang 116 of a ring element 1 arranged subsequently in the row to engage interlockingly in the notch 113 and in the cutaway 119, respectively, of the respective preceding ring element 1 in the row. FIG. 6 shows such a row of inter-engaged dimensionally stable ring elements 1 which have been inserted into an outer cover 43. For that purpose, for the purpose of better understanding a window has been inserted in outer cover 43 in the drawing, through which the engagement of the teeth in the notches of the dimensionally stable ring elements 1 arranged one after the other in a row is visible. FIG. 6 also shows that the first dimensionally stable ring element 1 inserted into the outer cover 43 engages by means of its tooth 109 in an exactly fitting notch present in the outer cover 43 (or in a flange of the outer cover). Such engagement of the tooth 109 of the first dimensionally stable ring element 1 in the notch in the flange of the outer cover 43 enables the entire row of dimensionally stable ring elements 1 to be secured against twisting.

(23) Furthermore, the outer cover 43 is screwed at its opposite ends to a first end ring 44 and a second end ring 45 (see FIG. 7), which seal the container wall 50 from the outside at the respective ends and accordingly ensure that the heat transfer medium flows through the inlet 40 into one end 101 of the helical channel 100, through the helical channel 100 and out of the outlet 42 again through the other end 103 of the helical channel 100. In addition, the dimensionally stable ring elements 1 of the heat exchanger casing 3 are held together in the axial direction by the second end ring 45 in order to ensure that they are secured against twisting (engagement of the tooth in the outer cover 43 at the other end).

(24) FIG. 7 and FIG. 8 show that when the heat exchanger casing 3 is arranged around the container wall 50 of the grinding container 5, the dimensionally stable ring elements 1 with the dividing walls 11 extending helically around the cylinder axis, together with the container wall 50, form a helical channel 100. The helical channel 100 has a first end 101 and a second end 103 remote from the first end. The inlet 40 for the heat transfer medium of the agitator ball mill 4 is connected to the first end 101 of the helical channel 100, and the outlet 42 for the heat transfer medium is connected to the second end 103 of the helical channel 100. Accordingly, the heat transfer medium, for example water, is able to flow through the helical channel 100 from the inlet 40 to the outlet 42. The water is in direct contact with the container wall 50 of the grinding container 5, with the result that especially good heat exchange (for example cooling) of the container wall 50 can be achieved. The throughflow direction of the water through the helical channel 100 can be opposite to the bending direction of the flexible sealing lip 128. This has the result that the water flowing through the helical channel 100 in the opposite direction to the bending direction of the sealing lip 128 presses the flexible sealing lip 128 even more firmly against the container wall 50, thus further supporting the sealing tightness of the helical channel 100.

(25) FIG. 9, FIG. 10 and FIG. 11 each shows a second exemplary embodiment of the dimensionally stable ring element 2 and of a heat exchanger casing 3 having dimensionally stable ring elements 2 of the second exemplary embodiment of the invention. Some of the aspects already discussed in relation to the first embodiment apply likewise to the second embodiment, so that those aspects and their function will not be explained again here. In this regard reference is made to the corresponding parts of the description of the first exemplary embodiment.

(26) In the second embodiment, the dimensionally stable ring element 2 comprises a cylindrical sleeve 20 having the cylinder axis 202 and a first end 204 as well as a second end 206 remote from the first end. The dimensionally stable ring element 2 comprises a (dimensionally stable) dividing wall 21 which projects inwards from an inner wall 208 of the cylindrical sleeve 20 and extends helically around the cylinder axis 202 along the inner wall 208 from the first end 204 to the second end 206. The cylindrical sleeve 20 can be made, for example, from polyamide. In particular, the sleeve 20 and the dividing wall 21 can both be injection-moulded from polyamide in a single step with the aid of a one-component injection-moulding process.

(27) At its first end 204 the cylindrical sleeve 20 has a tooth 209 extending parallel to the cylinder axis 202. At its second end 206 the cylindrical sleeve 20 likewise has a notch 213 extending parallel to the cylinder axis 202 and complementary in shape to the tooth 209. The tooth 209 has a tooth length 212 and a tooth width 210, and the notch has a notch depth 215 corresponding to the tooth length 212 and a notch width 214 corresponding to the tooth width 210.

(28) Furthermore, the cylindrical sleeve 20 comprises, at the first end 204, an overhang 216 extending along the circumference of the sleeve. The sleeve likewise has, at its second end, a cutaway 210 complementary in shape to the overhang. The overhang 216 has an overhang length 218 (see FIG. 10) in the direction of the circumference of the sleeve and an overhang width 217 in the direction of the cylinder axis 202. The cutaway 219 has a cutaway length 222 (see FIG. 10) corresponding to the overhang length 218 and a cutaway depth 220 corresponding to the overhang width 217.

(29) The dividing wall 21 extends helically around the cylinder axis 202 from the overhang 216 at the first end 204 of the sleeve 20 to the cutaway 219 at the second end of the sleeve 20 and has a dividing wall width 226 (see FIG. 9) that is smaller than or equal to the overhang width 217 of the overhang 216. Furthermore, the dividing wall 21 has a dimensionally stable bead 228 which projects inwards from the inner wall 208 of the sleeve 20.

(30) The dimensionally stable bead 228 has an inner edge 230 having an internal diameter 232, that internal diameter 232 being larger than the external diameter 500 of the container wall 50 of the grinding container 5, so that a narrow gap is formed between the inner edge 230 of the dimensionally stable bead 228 and the container wall 50 of the grinding container 5. The very slightly larger internal diameter 232 at the inner edge 230 of the dimensionally stable bead 228 prevents the (dimensionally stable and therefore inflexible) dividing wall 21 of the cylindrical sleeve 20 from being damaged during mounting on the grinding container 5. Although the narrow gap formed in that way means that very slight leakage is possible, the heat transfer medium, apart from that very slight leakage, nevertheless flows through the helical channel similarly to the first exemplary embodiment, so that the mode of action is in principle the same as in the first exemplary embodiment.

(31) The assembly of the heat exchanger casing 3 with dimensionally stable ring elements 2 in accordance with the second exemplary embodiment is identical to the assembly of the heat exchanger casing 3 with dimensionally stable ring elements 1 in accordance with the first exemplary embodiment.

(32) The invention has been explained above with reference to exemplary embodiments. It will be clear, however, that the invention is not limited to those exemplary embodiments, but rather those exemplary embodiments serve merely for an understanding of the invention, so that modifications and/or additional aspects can be provided without departing from the teaching of the invention. The scope of protection is therefore defined by the following patent claims.