Pod drive

Abstract

The present invention relates to a pod drive that can improve the cooling performance of a built-in motor. An embodiment comprises a motor that is disposed inside a pod and provided with a stator and a rotor in order to provide rotational force to a drive shaft. The stator includes: a stator core that is fixed inside the pod and surrounds the drive shaft; a coil that is wound around the stator core; a plurality of stator channels through which a refrigerant flows and which are arranged along the axial direction of the stator core and extend in a circumferential direction inside the stator core; and a plurality of stator guides which extend radially and are arranged, spaced a certain distance from each other along the circumferential direction of the stator core, in each of the stator channels. At least some of the plurality of stator guides may include a curved portion formed by curving radial outer ends.

Description

Ford drivetrain

[0001] The present invention relates to a pod drive device capable of improving the cooling performance of a built-in motor.

[0002] A pod drive is used, for example, as a means of propulsion on a ship, and is located submerged, outside the hull and below the waterline. A pod drive comprises a motor installed within a pod. The pod is mounted to the lower portion of the hull via a support structure, and the motor's output shaft is connected to one or two propellers, which drive the propellers.

[0003] Pod drives using motors generate a significant amount of heat. This heat must be properly dissipated to maintain a constant and acceptable temperature during operation. Since the motor is in contact with the pod, most of the heat is dissipated into the seawater surrounding the pod.

[0004] However, parts of the motor that do not come into contact with the pod cannot be directly cooled by seawater, resulting in reduced cooling efficiency. To address this issue, a solution has been proposed: providing a refrigerant such as air or water. However, this approach results in high flow resistance and insufficient refrigerant flow at the bottom of the motor, resulting in higher temperatures than other parts of the motor. High temperatures within the motor can reduce the insulation life of the coils wound on the stator.

[0005] The purpose of the present invention is to provide a pod drive device capable of improving the cooling performance of a built-in motor by improving the flow of refrigerant passing through the motor.

[0006] According to one embodiment of the present invention, a pod drive device includes: a pod installed on a ship via a support member and having a drive shaft for driving a propeller; and a motor disposed within the pod and having a stator and a rotor for providing rotational force to the drive shaft, wherein the stator includes: a stator core fixed within the pod and arranged to surround the drive shaft; a coil wound around the stator core; a plurality of stator channels arranged along an axial direction of the stator core and extending circumferentially within the stator core, the plurality of stator channels through which a refrigerant flows; and a plurality of stator guides arranged at predetermined intervals along a circumferential direction of the stator core in each stator channel and extending radially, wherein at least some of the plurality of stator guides may include curved portions formed by curved radially outer ends.

[0007] According to an embodiment of the present invention, it is possible to provide a pod drive device in which the cooling performance of the built-in motor is improved by increasing the flow rate of the refrigerant flowing inside the motor.

[0008] FIG. 1 is a side cross-sectional view illustrating a portion of a pod drive device according to one embodiment of the present invention.

[0009] Fig. 2 is a cross-sectional view taken along line A-A' of Fig. 1.

[0010] Figure 3 is a cross-sectional view taken along line B-B' of Figure 1.

[0011] Hereinafter, the present invention will be described in detail with reference to exemplary drawings. When designating components in each drawing, it should be noted that, where possible, identical components are given the same reference numerals, even if they appear in different drawings.

[0012] In this specification, a vessel refers to various types of vessels that move objects to be transported, such as people, animals, or goods, from a point of origin to a destination on or in water.

[0013] Additionally, terms such as "lower," "below," "bottom," "upper," "upper and lower," "front," "rear," "front and back," "left and right," and "transverse" used in connection with direction and arrangement are defined with respect to the vessel or hull. Terms such as "axial," "circumferential," and "radial" are defined with respect to the center line of rotation of the motor and drive shaft.

[0014] Fig. 1 is a side cross-sectional view illustrating a portion of a pod drive device according to one embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line A-A' of Fig. 1, and Fig. 3 is a cross-sectional view taken along line B-B' of Fig. 1.

[0015] As shown in these drawings, a pod drive device according to one embodiment of the present invention may include a pod (10) and a motor (30).

[0016] The pod (10) is formed in a roughly oval capsule shape and can be installed on the lower part of the ship's hull via a support member (11). The pod may be equipped with a drive shaft (20) that drives at least one propeller (not shown). The propeller is positioned at the rear end of the pod with respect to the ship's direction of travel, and is fixedly connected to the drive shaft so as to rotate together with the drive shaft. However, the arrangement of the propeller is not necessarily limited to this.

[0017] For steering the vessel, the pod (10) can rotate relative to the hull about a vertical axis (V) via a support (11). Since various means for rotating the pod are already known, a detailed description thereof will be omitted herein.

[0018] Thus, the pod drive unit is positioned outside the hull and underwater below the water surface, and can be used to drive the propeller and propel the vessel.

[0019] Optionally, a plurality of partition walls (12) may be installed within the support (11), which are spaced apart from each other in the width direction of the support and formed to extend up and down along the vertical axis (V). These partition walls may be connected to each other by a connecting plate (13) extending in the width direction of the support at the lower portion adjacent to the motor (30). These partition walls divide the refrigerant flow paths (i.e., 21 and 22) on the left, right, and center within the support, which may be used as passages for the refrigerant flowing to cool the motor.

[0020] Here, the refrigerant may be air, but is not necessarily limited thereto, and any other gas may be used as the refrigerant, and even liquids such as water or oil may be used. In addition, a pumping means (not shown) such as a compressor, blower fan, or pump may be provided on the hull to ensure the flow of the refrigerant.

[0021] For example, the space between the plurality of bulkheads (12) and the connecting plate (13) can be used as an inlet passage (21) through which refrigerant flows. Since the space between the bulkheads is open to the front and rear, the refrigerant flowing into the inlet passage can flow forward and backward of the pod (10) within the support member (11).

[0022] Additionally, the space between the bulkhead (12) and the inner wall of the pod (10) can be used as an outlet (22) through which the refrigerant flows out. The refrigerant that has passed through the inside of the motor (30) can rise along the outlet within the support (11) with the heat contained therein and flow out of the support.

[0023] Additionally, a support plate (14) formed to support the motor (30) may be connected to a connecting plate (13) provided within the support member (11) at positions corresponding to the axial front and rear ends of the motor (30). A support ring (15) may be provided at the lower portion of the support plate. The support ring may be connected to and supported by a support block (16) on the inner wall of the pod (10).

[0024] Additionally, a reinforcing plate (17) may be further placed between a pair of support plates (14) to supplement the rigidity of supporting the motor (30) and prevent sagging of the motor. The reinforcing plate may be installed to connect the connecting plate (13) and the motor (30).

[0025] A motor (30) is placed within the pod (10) and is coupled to a drive shaft (20) to provide rotational force to the drive shaft. This motor is used to drive a propeller to propel a ship.

[0026] The motor (30) may include a stator (31) arranged to surround a drive shaft (20) while being fixed within the pod (10); and a rotor (32) coupled to the drive shaft within the pod and capable of rotation, with the stator and the drive shaft spaced apart. The output of the motor may be provided by the rotor supported within the stator and capable of rotation smoothly and without friction.

[0027] The stator (31) includes a stator core (33) fixed within the pod (10) and surrounding a drive shaft (20), and a coil (34) wound around the stator core. The stator may be formed in a substantially hollow cylindrical shape so that the drive shaft (20) can pass through it, and may be fixedly supported by a support plate (14) and a support ring (15) within the pod (10), and a reinforcing plate (17).

[0028] The stator core (33) is provided with a plurality of stator core plates formed from electrical steel plates in a predetermined shape, and can be formed by stacking the plurality of stator core plates in the axial direction.

[0029] On the outer surface of each stator core plate, a plurality of notches (35) having the same size and a cross-section in the shape of a dovetail, for example, may be formed at a certain angle in the circumferential direction. When stacking a plurality of stator core plates in the axial direction, these notches must be aligned and communicate with each other.

[0030] When a plurality of stator core plates are axially stacked, a clamp bar (40) is inserted in the axial direction of the stator (31) into each row of notch portions (35) that are aligned and connected to each other, thereby joining the plurality of stator core plates and forming a stator core (33). The clamp bar is formed as a thin and long bar, and the radially inner portion of the clamp bar is inserted into the notch portion of the stator core (33).

[0031] Additionally, compression rings (36) may be placed on the exposed surfaces of the stator core plates at the front and rear ends of the stator core (33), respectively. Both ends of the clamp bar (40) that meet the compression rings may be firmly fixed to the outer peripheral ends of the compression rings.

[0032] Such fixation can be achieved by forming a plurality of notches (35) having the same shape, size, arrangement, etc. as the plurality of notches (35) in each stator core (33) at the outer peripheral end of the compression ring, and inserting each end of the clamp bar (40) into each of these notches.

[0033] The compression ring (36) of the stator core (33) and the support ring (15) of the support plate (14) can be fixedly connected to each other, for example, by shape fitting using a step portion and / or bolting using a separate bracket. As a result, axial movement of the motor (30) and the drive shaft (20) can be prevented.

[0034] In addition, at least one notch portion having the same shape, size, arrangement, etc. as the plurality of notches (35) in each stator core (33) is formed on the inner surface of the support ring (15) and the lower surface of the reinforcing plate (17), and a radially outer portion of a clamp bar (40) having a larger cross-sectional size among the clamp bars is inserted into the notch portion, so that the stator core can be fixed and supported on the support ring and the reinforcing plate. As a result, circumferential movement of the motor (30) and the drive shaft (20) can be prevented.

[0035] According to this configuration, the stator (31) and the motor (30) including the stator (31) can be stably placed and supported within the pod (10) by the support plate (14), the support ring (15), and the reinforcing plate (17). At this time, the stator core (33) can be substantially spaced apart from the inner wall of the pod at a predetermined interval.

[0036] The stator core (33) may include a rotor receiving hole (37) formed to extend axially so that a rotor (32) can be received at the center. In addition, the stator core may include a plurality of slots (38) and a plurality of poles (39) formed alternately around the periphery of the rotor receiving hole.

[0037] A plurality of poles (39) can be arranged at equal intervals along the circumference of the stator core (33), and a slot (38) can be formed between two adjacent poles.

[0038] A coil (34) is wound on a stator core (33) through a slot (38). A stator (31) can be formed by winding a coil in each slot (38) of the stator core.

[0039] In the stator (31), the stator core (33) may include a plurality of stator channels (23) formed at predetermined intervals along the axial direction of the stator core and extending in the circumferential direction of the stator core. Alternatively, the stator core may include a plurality of core blocks, and the stator channels may be formed between two adjacent core blocks.

[0040] Each stator channel (23) may include a plurality of stator guides (25) that are arranged at a predetermined interval along the circumference of the stator core (33) and extend radially. These stator guides may not only guide the flow of refrigerant, but may also serve as spacers that maintain the gap between two adjacent core blocks.

[0041] Moreover, at least some of the plurality of stator guides (25) may include a curved portion (26) formed by curving the radially outer ends. The curved shape of the outer ends may have an orientation toward the upper portion of the pod (10). In addition, the curved shapes of the outer ends of the plurality of stator guides may have shapes that are symmetrical to each other on the left and right of the pod with respect to the vertical axis (V) passing through the rotational center line (C).

[0042] In the stator channel (23), the stator guide (25) adjacent to the clamp bar (40) of the stator core (33) can avoid interference with the notch portion (35) by reducing its radial length and omitting the curved portion.

[0043] The rotor (32) includes a rotor core (43) coupled to a drive shaft (20) within a pod (10), and a plurality of magnets (44) inserted into the rotor core. The rotor can be fixedly coupled to the outer surface of the drive shaft with the drive shaft (20) penetrating therethrough, and can be accommodated in a rotor receiving hole (37) of a stator (31) to rotate around a rotation center line (C) together with the drive shaft and the propeller.

[0044] The rotor core (43) is provided with a plurality of rotor core plates formed from electrical steel plates in a predetermined shape, and can be formed by stacking the plurality of rotor core plates in the axial direction.

[0045] The rotor core (43) may include an axially extending shaft insertion hole (45) formed in the center so that a drive shaft (20) can be inserted. In addition, the rotor core may include a plurality of magnet insertion holes (46) formed around the periphery of the shaft insertion hole and into which magnets (44) are inserted.

[0046] For example, the rotor core (43) may be formed in a ring shape, a drive shaft (20) may be inserted and penetrated into the inner periphery of the rotor core, and a plurality of magnets (44) may be inserted and arranged in the outer periphery of the rotor core.

[0047] A plurality of magnet insertion holes (46) can be formed in the same shape and arranged at equal intervals along the circumference of the rotor core (43) while being spaced apart from each other.

[0048] The magnet (44) can be formed to have a cross-sectional shape corresponding to the cross-sectional shape of the magnet insertion hole (46), and a plurality of magnets can also be formed with the same shape. The rotor (32) can be configured by inserting and arranging magnets in each magnet insertion hole of the rotor core (43).

[0049] In the rotor (32), the rotor core (43) may include a plurality of rotor channels (24) formed at predetermined intervals along the axial direction and extending in the circumferential direction of the rotor core. Alternatively, the rotor core may include a plurality of core blocks, and the rotor channels may be formed between two adjacent core blocks.

[0050] Each rotor channel (24) may include a plurality of rotor guides (27) that are arranged at a predetermined interval along the circumference of the rotor core and extend radially. These rotor guides may not only guide the flow of refrigerant, but may also serve as spacers that maintain the gap between two adjacent core blocks.

[0051] The rotor channel (24) formed in the rotor core (43) is arranged and aligned to correspond to the stator channel (23) formed in the stator core (33) so that they can be smoothly connected to each other.

[0052] Furthermore, in the rotor (32), the rotor core (43) may include a plurality of through holes (28) formed at predetermined intervals along the circumference and extending in the axial direction of the rotor core. These through holes may guide the axial flow of the refrigerant. These through holes may be respectively connected to a plurality of rotor channels (24).

[0053] Accordingly, when refrigerant is supplied into the pod (10) through the inlet (21) in the support (11), as indicated by arrows in FIGS. 1 and 2, the refrigerant flows axially along the plurality of through holes (28) of the rotor core (43) provided in the axial direction of the drive shaft (20) from the front and rear of the motor (30), flows radially along the rotor channel (24) formed in the rotor core, and then flows into the stator channel (23) formed in the stator core (33).

[0054] The refrigerant can pass through the inside of the motor (10), transfer heat, be discharged to the outside of the motor, and then rise along the outlet (22) in the support (11) and flow out of the support. This flow of the refrigerant allows the rotor (32) and the stator (31), i.e. the motor (30), to be cooled.

[0055] In this case, a vortex is generated in the flow of the coolant at the lower part of the motor (30), which reduces the flow rate of the coolant, thereby lowering the cooling performance of the motor, and thus causing the temperature to become higher than that of other parts of the motor.

[0056] In a pod drive device according to one embodiment of the present invention, at least some of the plurality of stator guides (25) include a curved portion (26) formed by having a radially outer end curved, thereby preventing a vortex from being formed in the flow of refrigerant discharged to the outside of the motor (30), and by guiding the refrigerant toward the upper portion of the pod (10), the refrigerant can flow smoothly and quickly without loss due to resistance and be discharged.

[0057] Therefore, the pod drive device according to one embodiment of the present invention has the advantage of improving the cooling performance of the built-in motor by increasing the flow rate of the refrigerant flowing inside the motor.

[0058] Meanwhile, as described above, since the stator core (33) is spaced apart from the inner wall of the pod (10) at a predetermined distance and does not come into contact with the pod, direct cooling by seawater cannot occur, which may result in a decrease in cooling efficiency. In particular, the lower part of the motor (30) may become hotter than other parts of the motor due to low cooling efficiency, which may result in the formation of a hot spot.

[0059] A pod drive device according to one embodiment of the present invention may further include at least one heat-conducting member (41) disposed between the stator core (33) and the inner wall of the pod (10) so as to contact the stator core (33) and the inner wall of the pod (10).

[0060] The heat-conducting member (41) can be formed and arranged in the shape of a long bar extending along the axial direction of the motor (30) and having a predetermined thickness at the lower part of the inner wall of the pod (10).

[0061] In the example shown in Fig. 1, the heat-conducting member (41) may have a length that is almost the same as or slightly shorter than the length of the motor (30), but is not necessarily limited thereto.

[0062] The radial inner surface of the heat-conducting member (41) contacts the radial outer surface of the stator core (33). As a result, heat generated within the motor (30) is transferred from the stator (31) to the pod through the heat-conducting member, and the heat transferred to the pod can be released into the seawater surrounding the pod.

[0063] As described above, according to an embodiment of the present invention, it is possible to provide a pod drive device in which the cooling performance of the built-in motor is improved by increasing the flow rate of the refrigerant flowing inside the motor.

[0064] The above description is merely an example of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention.

[0065] Accordingly, the embodiments disclosed in the present invention are intended to illustrate, rather than limit, the technical concepts of the present invention, and the scope of the technical concepts of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical concepts within the scope equivalent thereto should be construed as being included within the scope of the present invention.

[0066] The present invention is useful, for example, as a propulsion means for a ship.

Claims

1. A pod installed on a ship via a support member and having a drive shaft for driving a propeller; and A motor having a stator and a rotor arranged within the above pod and providing rotational force to the driving shaft Including, The above stator is, A stator core arranged to surround the drive shaft while being fixed within the pod; A coil wound on the above stator core; A plurality of stator channels arranged along the axial direction of the stator core and formed to extend circumferentially within the stator core, through which refrigerant flows; and In each stator channel, a plurality of stator guides are arranged and spaced apart from each other at a predetermined interval along the circumference of the stator core and formed to extend radially. Including, A pod drive device wherein at least some of the plurality of stator guides include a curved portion formed by having a radially outer end curved.

2. In paragraph 1, The above-mentioned curved portion is a pod drive device having a curved orientation so as to face the upper part of the pod.

3. In paragraph 2, A pod driving device in which the above plurality of stator guides have a shape symmetrical with respect to the left and right of the pod.

4. In paragraph 1, The above support part, A plurality of baffles formed to be spaced apart from each other in the width direction of the support portion within the support portion and extending vertically; and A connecting plate extending in the width direction of the above support member to connect the above plurality of bulkheads Including, A pod drive device in which the refrigerant flow path within the support member is partitioned by the plurality of baffles.

5. In paragraph 4, The space between the above-mentioned plurality of bulkheads and the above-mentioned connecting plate constitutes an inlet passage through which the refrigerant flows in, The space between each bulkhead and the inner wall of the pod constitutes an outlet passage through which the refrigerant flows out, the pod drive mechanism.

6. In paragraph 4, A support plate is connected to the above connecting plate so as to support the motor at positions corresponding to the front and rear axial ends of the motor, A support ring is provided at the bottom of the above support plate, and the support ring is connected and supported to the inner wall of the pod by a support block. A pod drive device in which the stator core is fixedly supported by the support ring.

7. In paragraph 6, Between a pair of support plates, a reinforcing plate is additionally placed. The above reinforcing plate is a pod drive device connecting the above connecting plate and the above motor.

8. In paragraph 1, The above rotor, A rotor core coupled to the drive shaft within the pod; a plurality of magnets inserted into the rotor core; and A plurality of rotor channels formed to extend in a circumferential direction within the rotor core and through which refrigerant flows Including, A pod drive device wherein the rotor channel is arranged and aligned correspondingly with the stator channel.

9. In paragraph 8, The above rotor core includes a plurality of through holes formed to extend in the axial direction of the rotor core, Each through hole is a pod drive device communicating with the plurality of rotor channels.

10. In paragraph 1, A pod drive device further comprising at least one heat-conducting member disposed between the stator core and the inner wall of the pod so as to contact the stator core and be connected to the inner wall of the pod.

Images