Title of Invention

A DEVICE TO COOL HEAT EMITTING ELECTRICAL PARTS OF A TEXTILE MACHINE

Abstract

In a device for cooling of heat emitting electrical parts (24), heat exchangers (15, 23) for heat absorption i.e. heat emission are arranged, whereby the heat exchangers mainly consist of plates (16,26), which are provided with a channel (17) each. The heat absorbing plate (26) carries electrical parts (24), which transmit their power loss in the form of heat to said plate, and the plate (16) is provided with fins (18), against which an exhaust air stream (6) of a suction device (3) is directed. The device is characaterized by the low cost for manufacturing and mounting and is free of maintenance.

Full Text

The invention relates to a device to cool heat-emitting electrical parts of a textile machine. Cooling devices for textile machines are described in patent literature, for example in US patent 2,716,859 or in the European patent EP-Bl-0 326 688, where the heat emission of an electrical part, for instance of a motor, is taken off in tubes by means of cooling mediums and where, as heat exchangers, undulated tubes are used. Such heat exchangers have the disadvantage that they get easily dirty when in contact with air that contains fibre material, so that the cooling effect is reduced and it is necessary to initiate cleaning processes. It is the object of the present invention, to provide a device for cooling, which does not need special maintenance and which is easy to manufture and to install. This task as an object of the invention is solved according to the feature of the operative part of the independent claim. The objects of the depending claims relate to preferred further embodiments of the solution. With the device according to the invention, an effective emission of heat is possible at reasonable cost. Accordingly the present invention provides a device to cool heat emitting electrical parts of a textile machine in which a heat exchanger is arranged to at least one electrical part and a second heat exchanger is being placed in a channel, whereby the heat exchangers are connected through a flow line and return line for a cooling medium, characterized in that at least one of the heat exchangers is provided with a heat absorbing, respectively a heat emitting plate, to which a channel is furnished to guide the cooling medium . In the following the object of the invention is described more closely by way of the accompanying figure. Where is shown in Fig. 1 a side view onto the suction device and the control device of a textile machine in a schematical presentation. Fig. 2 a plan view of the arrangement in Fig. 1, fig. 3a a front view, a plan view and a side view of a plate b,c of the heat exchanger i.e. of a heat exchanger and fig. 3d a further embodiment of the heat exchanger. In a textile machine 1 as for instance in a ring spinning frame according to fig. 1 and 2 a casing 22 contains a suction device 3 and a control unit 2 arranged besides each other which are separated by a wall 21. By means of a rotor 4 air is sucked from the working units of the textile machine, said air is then transported as exhaust air stream 6 into a channel 5 with channel walls 5'. The exhaust air stream 6 is lead over a heat exchanger 15 and a motor 7, which rotates a shaft 9 by means of through a drive 8. Said shaft serves to drive spindles in a ring spinning frame, for which the device according to the invention is particularly used. The air stream is further channelled off according to the arrows 10 through an opening 11 in the floor of the spinning mill, whereby the waste heat of the heat exchanger 15 and of the motor 7 is drawn off. With electrical lines 28 the motor 7 is supplied with power through the control box 2, which is connected to the main 20. A transformer 25 is arranged together with other electrical parts such as circuit elements within the control box 2. Within the transformer 25 there is also a heat exchanger 23, which mainly consists of a plate 26 with a channel 27 for a cooling medium and a cover 29, which seals the channel 27 towards the outside. Onto the plate 26 in particular electrical parts 24 are mounted which have a high power loss. Such parts can be rectifiers, loss resistors or converters as part of the transformer 25, whereby the power loss can be in the range of IkW. By mounting the electrical parts 24 directly onto the plate 26 of the heat exchanger 23, the power loss in the form of exhaust heat, for its greater part is directly transmitted into the cooling system of the device, which consists of the two heat exchangers 15,23 and the connecting flow line 12 and the return line 13. In the flow line 12 a pump 14 for forced circulation of the cooling medium 12c is used. Above the flow line 12 there is the expansion line 12a with an expansion tank 12b for the cooling medium 12c. The heat exchanger 15 consists, like the other heat exchanger 23, also basically of a plate 16, into which, as can be seen from figs 3a - 3c, a channel 17 is mill-cut. It is also possible to fasten a tube onto the surface of the plate 16 or put such a tube into a groove of the plate. According to fig. 3c, a cover 19 is screwed onto the plate 16 at the points marked with crosses, using sealing compound in-between. At the ends of channel 17 there are, according to fig. 3c, openings in the cover 19, where the flow line 12 i.e. the return line 13 is connected. For the improvement of the heat transmission of the heat exchanger 15 onto the air within the channel 5, at the opposite side of channel 17, fins 18 are arranged which are in parallel alignment to the flowing direction of the exhaust air stream 6. By arranging the heat exchanger 15 directly next to the rotor 4, the exhaust air stream 6 is concentrated directly onto this heat exchanger 15, which results in an efficient heat emission. As previously indicated, the heat exchanger 23 is practically of the same design as the heat exchanger 15, whereby in place of the fins 18 in the heat exchanger 15, the heat emitting parts 24 are arranged in the heat exchanger 23, as shown in fig. 2. The rearside of the heat exchanger 23 can preferably be covered by an insulation 30, which can extend as an insulation 31 all around the frequency transformer 25. Thus the heat flow from the electrical parts 24 can be directed in particular in the direction of the cooling medium in the heat exchanger 23. To keep the effort of maintenance for the heat exchanger 15 low, the surfaces contacted with cooling air have to be structured in such a way that no contamination, such as textile fibres, may adhere on them. The fins 18 have to be at least 5 mm apart, the fin surface has to be smooth (surface quality N8), and on the side where the air stream meets the surface, the fins have to be slanted at an angle of at least 45 ". In order to achieve a good heat transmission from the el'ectrical parts 24 to the channel 27 by means of the cooling medium 12c, between the mounting surface for the electrical parts 24 on the plate 26 and the channel 27 a space of maximum 5 mm, in particular 3 mm should be provided. As a cooling medium water with an addition of corrosion-preventing substance is used, for instance antifreezing agent as it is used in the automotive industry. In contrary to an open cooling system, where water is continuously drawn from the water supply network and after absorption of the loss heat is drawn off by the system, the closed fluid circuit 12,13,15,23 has the advantage that no condenser water can develop in the cooling circuit since the cooling medium 12c is of a temperature above the temperature of the surrounding air. The heat exchanger 15 instead of being installed within channel 5 of a suction device 3 may be placed in any channel of an air device. Heat exchanger 15, expansion tank 12b, pump 14 and lines 12 and 13 are arranged in such a way that the system is self-venting (fig. 1). The expansion tank 12b is located in such a way that it is approx. 1 m above the heat exchanger 15. The heat exchanger 23 is insulated against the surrounding air in such a way that as little as possible heat is emitted into the control box and that as much as possible heat is drawn off through the return line 13. The electrical parts are for instance electronical (power-) actuating elements or SERVO-amplifiers or resistors or DC/DC-transformers. The undulation of the channel 17 can be arranged vertically instead of horizontally as shown in fig. 3a. The channel 17, as shown in fig 3d can also be designed to comprise several parallel channel parts 17' with the same flow resistance each for the flow medium 12c. WE CLAIM: 1. A device to cool heat emitting electrical parts (24,25) of a textile machine (1) in which a heat exchanger (23) is arranged to at least one electrical part (24) and a second heat exchanger (15) is being placed in a channel (5) whereby the heat exchangers (15, 23) are connected through a flow line and return line (12 or 13) for a cooling medium (12 c), characterized in that at least one of the heat exchangers is provided with a heat absorbing, respectively a heat emitting plate (16, 26), to which a channel (17, 27) is furnished to guide the cooling medium (12 c). 2. The device according to claim 1, wherein the channel (17, 27) is integrated in the plate (16, 26). 3. The device according to claim 2, wherein the channel (17, 27) is an undulating type channel. 4. The device according to claim 1, 2 or 3, wherein the channel is open on one side of the plate and a cover (19, 29) is provided to close the channel (17, 27). 5. The device according to one of the preceding claims, wherein one side of the plate (16) is provided with fins (18) or electrical parts (24), in particular electronical actuating elements or SERVO amplifiers or resistors or DC/DC transformers. 6. The device according to claim 5, wherein the heat exchanger (15) with the fins (18) is located within the channel (5) in particular in a suction device (3). 7. The device according to claim 5, wherein the heat exchanger (23) with the electrical parts (24) is part of a frequency transformer (25), 8. The device according to one of the preceding claims, wherein the flow line (12) and the return line (13) enters the channel (17,27). 9. The device according to claim 6, wherein the heat exchanger (15) is arranged in the channel (5) in such a way that the plate (16) is parallel to a channel wall and the fins (18) are oriented in the direction of an air stream or of an exhaust air stream (6). 10. The device according to one of the claims 5 to 9, wherein the fins (18) are at least 5 mm spaced apart and they are slanted on the side opposite to the direction of the air stream, at an angle of at least 45° and they have a surface quality of at least N8. 11. The device according to one of the preceding claims, wherein the channel (17,27) reaches up to at least 5 mm, in particular 3 mm, to the heat absorbing, respectively to the heat emitting surface of the plate on the side opposite the channel (17,27). 12. The device according to claim 8, wherein an expansion tank (12b) is attached to the flow line or the return line (12, 13). 13. The device according to one of the claims 5, 7, 8, 11, 12, wherein the heat exchanger (23) is heat insulated against the surrounding air so that as little as possible heat is emitted to the surrounding and as much as possible heat is carried off through a return line (13). 14. A device to cool heat emitting electrical parts of a textile machine substantially as herein described with reference to the accompanying drawings.

Documents:

1197-mas-95 abstract.jpg

1197-mas-95 abstract.pdf

1197-mas-95 claims.pdf

1197-mas-95 correspondence others.pdf

1197-mas-95 correspondence po.pdf

1197-mas-95 description (complete).pdf

1197-mas-95 drawings.pdf

1197-mas-95 form-1.pdf

1197-mas-95 form-26.pdf

1197-mas-95 form-4.pdf

1197-mas-95 petition.pdf