JP2023056833A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine capable of suppressing the influence of heat on a member.SOLUTION: A rotary electric machine 1 according to an embodiment includes a frame 2 housing a stator 4 and a rotor 5, a bracket 3 that closes the opening of the frame 2, a shaft 6 fixed to and rotating with the rotor 5, a bearing 7 that rotatably supports the shaft 6, and a radiator 8 mounted on the shaft 6 between the rotor 5 and the bearing 7 in the axial direction and having a heat radiation surface 8a facing the inner surface of the bracket 3.SELECTED DRAWING: Figure 1

Description

An embodiment of the present invention relates to a rotating electric machine.

2. Description of the Related Art Conventionally, a rotating electric machine in which a stator and a rotor are arranged in a frame may be cooled by providing a fan (see, for example, Patent Document 1).

JP 2019-54650 A

However, conventionally, cooling has been performed based on the technical concept of cooling the member to which heat has been transferred, so it has been difficult to suppress the effect of heat itself on the member.
Therefore, a rotating electric machine is provided that can suppress the influence of heat on members.

A rotating electrical machine according to an embodiment includes a frame that houses a stator and a rotor, a bracket that closes an opening in the frame, a shaft that is fixed to and rotates with the rotor, a bearing that rotatably supports the shaft, and a shaft that supports the shaft in an axial direction. a radiator mounted on the shaft between the rotor and the bearing in and having a heat radiating surface facing the inner surface of the bracket.

1 is a diagram schematically showing a configuration example of a rotating electric machine according to a first embodiment; FIG. The figure which shows the structural example of a radiator typically The figure which shows the structural example of a shielding member typically. A diagram schematically showing another configuration example of a rotating electric machine The figure which shows typically the other structural example of a radiator. FIG. 11 is a diagram schematically showing another configuration example and mounting mode example of the shielding member; A diagram schematically showing a configuration example of a rotating electric machine according to a second embodiment. Schematically showing a configuration example of a shielding heat transfer member The figure which shows typically the other structural example of a shielding heat-transfer member. A diagram schematically showing another arrangement example of the shielding heat transfer member

A plurality of embodiments will be described below with reference to the drawings. Also, the same reference numerals are given to substantially common parts in each embodiment.

(First embodiment)
The first embodiment will be described below. As shown in FIG. 1, a rotating electric machine 1 includes a frame 2 formed in a cylindrical shape with both ends opened, brackets 3A and 3B closing the openings on both ends of the frame 2, and fixed to the inner surface of the frame 2. a rotor 5 arranged with a predetermined gap on the inner peripheral side of the stator 4; a shaft 6 attached to the rotor 5; A bearing 7 for rotatably supporting a shaft 6 and a radiator 8 fixed to the shaft 6 are provided. Hereinafter, the direction along the rotation axis (J1) of the shaft 6 is called the axial direction, the direction perpendicular to the axial direction is called the radial direction, and the direction around the axial direction is called the circumferential direction.

In this embodiment, the frame 2 is formed in a cylindrical shape with a circular inner peripheral surface, and a fixing structure (not shown) for fixing the stator 4 is provided on the inner peripheral surface. The bracket 3 accommodates the bearing 7 and is formed in a generally disk-like shape expanding radially outward from the bearing 7 side. It is

As is well known, the stator 4 is formed hollow by laminating iron core pieces obtained by punching electromagnetic steel sheets into a circular shape, and has a plurality of slots for mounting coils on its inner peripheral surface. The coil inserted into the slot forms coil ends 4a in which portions protruding to both ends in the axial direction are formed along the end faces of the stator 4. As shown in FIG. The coil end 4a is formed so as to fit into a predetermined shape in the axial and radial directions.

As is well known, the rotor 5 is formed by laminating iron core pieces obtained by punching electromagnetic steel sheets into an annular shape, and a hole 5a into which the shaft 6 is inserted is formed at the center. In the case of this embodiment, an induction-type rotating electric machine 1 is assumed, and the rotor 5 has conductors such as aluminum and copper inserted into a plurality of slots formed therein, and has two ends in the axial direction. A short-circuit ring 5b connecting the conductors to each other is formed in a shape having a fin. However, the configuration of the rotating electrical machine 1 is an example and is not limited to this.

The shaft 6 is made of a metal material, is press-fitted into the hole 5 a of the rotor 5 , and rotates around a rotation axis that rotates together with the rotor 5 . Further, the shaft 6 is formed with steps at positions corresponding to both sides of the rotor 5 so that the diameter on the side opposite to the rotor 5 in the axial direction is relatively small. Defined.

The radiator 8 is made of a metal material such as stainless steel, and is fixed to the shaft 6 at a position between the rotor 5 and the bearing 7 in the axial direction. The heat radiator 8 is formed in a shape extending radially outward from the shaft 6 side, and has a flat heat radiation surface 8a facing the inner surface of the bracket 3, here the flat surface 3a. Hereinafter, the portion where the heat dissipation surface 8a is formed is also referred to as a heat dissipation portion 8b for convenience.

Specifically, as shown in FIG. 2, the radiator 8 has a circular outer shape when viewed from the front in the axial direction, and an insertion hole 8c into which the shaft 6 is inserted is formed at the center. It is A key groove 8d into which a key of the shaft 6 is inserted is formed in a part of the circumferential direction of the insertion hole 8c, thereby preventing a relative displacement with respect to the shaft 6. As shown in FIG. Further, in this embodiment, the radiator 8 is provided with a fixing hole 6e that communicates from the radially outer side to the inner surface of the insertion hole 8c, and is fixed to the shaft 6 by, for example, bolts. However, it is also possible to adopt a configuration in which only press fitting or only bolts are used for fixing.

In addition, as seen in a side view in the radial direction, the radiator 8 is formed so that the right side of the drawing, which is on the side of the stator 4 and the rotor 5, does not interfere with the short-circuit ring 5b and the coil end 4a. . In this embodiment, the radiator 8 is formed stepwise to avoid the short-circuit ring 5b and the coil end 4a. Further, the radiator 8 is formed with a relief portion 8e recessed from the surface with a predetermined diameter so as not to interfere with the bearing 7 on the surface on the right side in the drawing, which is on the side of the bearing 7 . A flat surface formed on the outer peripheral side of the relief portion 8e serves as the heat dissipation surface 8a in this embodiment.

The radiator 8 is formed, for example, by cutting out a short cylindrical metal material, and the surface on the left side of the drawing is continuous from the insertion hole 8c side to the outer edge of the heat dissipation surface 8a. Moreover, when the radiator 8 is attached to the shaft 6 , the insertion hole 8 c is closed by the shaft 6 . Therefore, when the radiator 8 is attached to the shaft 6, a flange-shaped heat radiating portion 8b is formed at the end on the left side of the drawing, and the surface thereof serves as the heat radiating surface 8a. It has a structure.

As shown in FIG. 1, the radiator 8 has an outer edge indicated by a dashed line (DL1) of the heat radiating portion 8b formed at the axial end of the stator 4 when viewed from the axial direction. The coil end 4a is formed to have a size that overlaps the inner edge indicated by the dashed line (DL2) of the coil end 4a in the radial direction. Therefore, the heat radiation surface 8a of the radiator 8 is parallel to the flat surface 3a of the bracket 3 with a predetermined gap therebetween, that is, the heat radiation surface 8a faces the flat surface 3a. Further, when the shaft 6 rotates and the radiator 8 rotates, the heat radiation surface 8a and the flat flat surface 3a face each other with a predetermined gap therebetween.

The diameter (R1) of the insertion hole 8c of the radiator 8 can be set based on the diameter of the shaft 6. As shown in FIG. In addition, the diameter (R2) of the first stepped portion and the diameter (R3) of the second step from the right side of the radiator 8 in the figure are set so that they do not come into contact with the short-circuit ring 5b and the coil end 4a and are set to a predetermined value. can be set to a size that can secure an insulation distance of However, the diameter (R2) of the first stepped portion is desirably as large as possible because it becomes a portion where heat from the shaft 6 is transferred when it comes into contact with the shaft 6 .

Also, the overall diameter (R4) of the radiator 8 can be appropriately set according to the size of the frame 2, the internal structure of the frame 2, and the like. The diameter (R5) of the relief portion 8e is within a range that does not interfere with the bearing 7. As will be described later, the width (W1) of the heat radiation surface 8a, which is a portion that radiates heat to the bracket 3, is made as large as possible. It is desirable to set it so that

Also, the overall thickness (T1) of the radiator 8 can be set according to the distance between the rotor 5 and the bearing 7, etc. However, it is possible to keep the distance between the heat radiating surface 8a and the flat surface 3a as short as possible. It is desirable to set Moreover, it is desirable that the thickness (T2) of the heat radiating portion 8b be as large as possible in order to increase the heat storage amount while ensuring a predetermined insulating distance from the coil end 4a. Also, the thickness (T3) of the insertion hole 8c, that is, the axial length of the insertion hole 8c, is a portion that contacts the shaft 6 and conducts heat from the shaft 6, so it is desirable to increase the thickness as much as possible. .

As shown in FIG. 1, the heat radiating portion 8b is provided with a shielding member 9 on the surface on the side of the coil end 4a. The shielding member 9 blocks at least part of direct heat radiation from the coil end 4a to the radiator 8, and is made of a material having heat resistance and relatively low thermal conductivity compared to the radiator 8. is formed by In this embodiment, the shielding member 9 is made of a heat-resistant rubber material, and is formed by attaching a highly reflective member such as aluminum foil to the surface on the side of the coil end 4a.

The shielding member 9 is adhered to the coil end 4a side surface of the heat radiating portion 8b with, for example, a heat-resistant adhesive. However, the shielding member 9 is not limited to a rubber material, and can be formed of a heat-resistant resin material or the like. It can be attached or attached to the radiator 8 by gluing and screwing.

As shown in FIG. 3, the shielding member 9 has an outer diameter (R10) approximately equal to or slightly smaller than the diameter (R1) of the radiator 8, and an inner diameter (R7) of the second paragraph of the radiator 8. It is slightly larger than the diameter (R3), and its thickness (T10) is set to be approximately the same as the thickness (T2) of the heat radiating portion 8b. Therefore, when the shielding member 9 is attached to the heat radiating portion 8b, the shielding member 9 shields substantially the entire area in the radial direction and the circumferential direction of the heat radiating portion 8b from the coil end 4a side.

That is, the shielding member 9 blocks at least part of the direct heat radiation from the coil end 4a to the radiator 8. blocks heat radiation. The shielding member 9 is not limited to the ring-shaped one shown in FIG.

Next, the operation of the configuration described above will be described.
As described above, since the conventional cooling method is based on the technical concept of cooling the member to which heat is transferred, it has been difficult to suppress the effect of heat itself on the member. For example, when the coil generates heat during operation, the heat is transmitted to the shaft 6 and then to the bearing 7 via the shaft 6 . If heat is transferred excessively, the bearing 7 may be damaged due to dimensional deviation due to thermal expansion, deterioration of lubricating oil, or the like.

Therefore, in this embodiment, the radiator 8 is provided in the rotary electric machine 1 . For example, as shown as a comparative example in FIG. , the heat is transmitted almost as it is to the bearing 7 side. As a result, heat is transferred to the bearing 7 that physically supports the shaft 6, and the temperature of the bearing 7 rises, which may cause damage as described above.

On the other hand, in the case of the rotary electric machine 1 according to this embodiment shown as an example, even if the heat indicated by the white arrow (V1) is transmitted to the shaft 6, part of the heat is ), and the rest is transmitted to the bearing 7 as indicated by a white arrow (V3). The heat transmitted to the heat radiator 8 is transmitted to the bracket 3 by radiation from the heat radiation surface 8a as indicated by the white arrow (V4), and is released to the outside from the outer surface of the blanket.

As a result, the rotary electric machine 1 of the present embodiment can reduce the heat transmitted to the bearings 7 compared to the conventional rotary electric machine 101 , that is, the effect of the heat itself on the bearings 7 can be suppressed. If the influence of heat on the bearing 7 is suppressed, the rise in the temperature of the bearing 7 is also suppressed, so that the possibility of causing damage as described above can be reduced.

By the way, the coil end 4a is a portion that becomes relatively hot in the rotary electric machine 1, and radiant heat is emitted from the coil end 4a as indicated by the black arrow (R1). In this case, if the temperature of the heat radiating portion 8b rises due to the radiant heat, the heat radiating performance from the heat radiating surface 8a may deteriorate, and the amount of heat taken from the shaft 6 may also decrease. Therefore, the rotary electric machine 1 is provided with the shielding member 9 on the coil end 4a side of the heat radiating portion 8b located on the side of the coil end 4a in the axial direction. As a result, it is possible to prevent the heat radiation from the coil end 4a from lowering the heat radiation from the heat radiation portion 8b.

According to the embodiment described above, the following effects can be obtained.
The rotary electric machine 1 includes a frame 2 that houses a stator 4 and a rotor 5, a bracket 3 that closes an opening of the frame 2, a shaft 6 that is fixed to the rotor 5 and rotates together, and a shaft 6 that is rotatably supported. and a radiator 8 which is attached to the shaft 6 between the rotor 5 and the bearing 7 in the axial direction and which has a heat radiation surface 8 a facing the inner surface of the bracket 3 . As a result, the heat transmitted to the shaft 6 can be released before it is transmitted to the members constituting the rotating electric machine 1, such as the bearings 7, so that the influence of the heat itself on the members can be suppressed.

Further, in the rotary electric machine 1, the radiator 8 is formed in such a size that the outer edge of the heat dissipation surface 8a overlaps the inner edge of the coil end 4a when viewed from the axial direction. In other words, the heat dissipation surface 8a is formed to have a size that extends radially to some extent. As a result, the opposing area between the heat dissipation surface 8a and the blanket can be set large, the amount of heat dissipation from the heat dissipation surface 8a to the blanket can be increased, and the heat dissipation performance of the radiator 8 can be improved. The radiators 8 can be attached to both sides of the rotor 5 in the axial direction by, for example, threading the shaft 6 and the radiator 8 .

The rotating electric machine 1 also includes a shielding member 9 that is attached to the coil end 4a side of the radiator 8 and blocks at least part of direct heat radiation from the coil end 4a to the radiator 8 . As a result, the heat from the coil end 4a, which reaches a relatively high temperature during operation, can be prevented from being transferred to the radiator 8, and the heat dissipation performance of the radiator 8 can be prevented from deteriorating.

In the embodiment, the radiator 8 having a plurality of steps on the outer peripheral side was exemplified. However, it is possible to adopt a configuration in which no steps are provided on the outer edge, such as a radiator 8A shown as a shape example 1 in FIG. 5, for example. . This makes it easier to secure the insulation distance from the coil end 4a. In addition, when the rotor 5 does not have a fin-shaped portion, the width (W10) of the portion in contact with the shaft 6 in a cross-sectional view is increased as much as possible after securing an insulation distance from the coil end 4a. By doing so, the amount of heat transferred from the shaft 6 can be increased. That is, the heat from the shaft 6 can be efficiently radiated from the heat radiation surface 8a.

In addition, as in the radiator 8B shown as the shape example 2, the outer edge on the coil end 4a side and the inner edge on the bearing 7 side may be inclined. In this case, either the outer edge or the inner edge can also be formed to be slanted. Further, in the case of a structure in which the bearing 7 is arranged outside the inner surface of the blanket, for example, as in the radiator 8C shown as the shape example 3, a flange-shaped heat radiating portion 8b is provided on the substantially cylindrical main body. A simple configuration such as With such a configuration as well, it is possible to secure the area of the heat radiation surface 8a while securing the insulation distance from the coil end 4a, and it is possible to manufacture easily.

Further, in the embodiment, the shield member 9 is provided on the surface of the heat radiating portion 8b on the side of the coil end 4a, but as shown in FIG. The shielding member 9A and the shielding member 9B having different thicknesses can be attached. In addition, as shown in mounting example 2, a shielding member 9C and a shielding member 9D are provided to cover the steps of the heat sink 8 from the outside in the radial direction, so that the heat from the coil end 4a is removed at least either in the axial direction or the outside in the radial direction. It can also be configured to block radiation.

In addition, as shown in mounting example 3, other structures such as the radiator 8A can also be configured to block heat radiation from the coil end 4a in at least one of the axial direction and the radial direction outside, for example. . Also, the shielding member 9 can be provided in the relief portion 8e. As a result, direct heat radiation from the heat radiator 8 to the bearing 7 is blocked, and the temperature rise of the bearing 7 can be suppressed.

In this way, by providing the shielding member 9 at a portion facing the coil end 4a, direct heat radiation from the coil end 4a to the radiator 8 can be blocked, and in the radiator 8, Since the heat radiation from the position where the shielding member 9 is provided is suppressed, the heat radiation amount from the heat radiation surface 8a relatively increases, and the heat transfer efficiency to the bracket 3, that is, the heat radiation efficiency via the bracket 3 is reduced. can be improved.

Although it has been described in the embodiment that the influence of heat on the bearing 7 is suppressed, the influence of heat on members attached to the shaft 6 outside the rotary electric machine 1 can also be suppressed. That is, the radiator 8 can suppress the influence of heat on the members forming the rotating electric machine 1 and the members attached to the shaft 6 . Further, in the embodiment, the configuration in which the radiators 8 are provided on both sides of the rotor 5 is illustrated, but the configuration in which the radiators 8 are provided on either one of them is also possible.

(Second embodiment)
A second embodiment will be described below. Since the main configuration of the rotary electric machine 1 of the second embodiment is common to that of the first embodiment, substantially common parts are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 7, the rotary electric machine 10 of this embodiment includes a frame 2, brackets 3A and 3B, a stator 4, a rotor 5, a shaft 6, bearings 7, a radiator 8, and the inner surface of the frame 2. It has a shielded heat transfer member 11 attached. As shown in FIG. 8, the shielding heat transfer member 11 has a shielding plate 11a formed in a hollow annular shape and a wall portion 11b rising from the outer edge of the shielding plate 11a and extending in the axial direction. and its cross section is generally L-shaped. The shielding heat transfer member 11 is made of, for example, a metal material having heat transfer properties.

At this time, the overall diameter of the shielding heat transfer member 11 is set to a size that allows it to be attached to the inner surface of the frame 2 . Further, the width (W20) of the wall portion 11b in the axial direction can be appropriately set within a range in which the wall portion 11b can be attached to the inner surface of the frame 2. As shown in FIG. A plurality of screw holes 11c for fixing to the inner surface of the frame 2 are formed in the wall portion 11b. In addition, the radial width (W21) of the shielding plate 11a is set within a range in which the shielding plate 11a does not come into contact with the radiator 8 when attached to the frame 2. As shown in FIG.

As shown in FIG. 7, the shielding heat transfer member 11 is formed by fixing the wall portion 11b to the frame 2 while the shielding plate 11a is positioned between the coil end 4a and the radiator 8 in the axial direction. It is attached. However, a predetermined insulating distance is ensured between the shield heat transfer member 11 and the coil end 4a. As a result, radiation heat from the coil end 4a indicated by the black arrow (R1) is blocked by the shielding heat transfer member 11 from radiation to the radiator 8, here the radiation portion 8b.

In this way, it is attached to the frame 2 and positioned between the radiator 8 and the coil end 4a to block at least part of the direct heat radiation from the coil end 4a to the radiator 8, By providing the shield heat transfer member 11 that transfers the received heat to the frame 2, the temperature rise of the heat dissipation portion 8b can be suppressed, and the heat transferred from the shaft 6 can be easily released to the bracket 3. It is possible to suppress the effect of heat itself on the

By the way, the shielding heat transfer member 11 is not limited to the annular shape described above, and can be configured to block heat radiation in a substantially annular shape as a whole by combining a plurality of members. For example, as shown in FIG. 9 as a shape example 1, parts 12A obtained by dividing the shielding heat transfer member 11 shown in FIG. 8 in the circumferential direction can be combined. In addition, in FIG. 9, the positions corresponding to the shield plate 11a and the wall portion 11b are denoted by reference numerals for the sake of explanation. At this time, the center angle (α) of the part 12A can be set as appropriate, but it is not necessary to arrange parts of the same shape. 11.

Alternatively, as shown in Shape Example 2, the shielding heat transfer member 11 has a wall portion 11b formed in a straight line, and the lower end side of the shielding plate 11a connected to the wall portion 11b, that is, the radiator 8 side. The shape of the part 12B can be formed in an arc shape that avoids the radiator 8. As shown in FIG. Further, as shown in Shape Example 3, the shielding heat transfer member 11 can also be configured by using a part 12C having a shape obtained by dividing the shape shown in Shape Example 2 into two in the horizontal direction of the drawing, for example.

The shielding heat transfer member 11 uses a part 12D in which the wall portion 11b side and the shielding plate 11a side are separate members, as shown in Shape Example No. 4. Alternatively, the wall portion 11b may be attached to the inner surface of the frame 2 in advance, and the shielding plate 11a may be attached after the necessary work is completed.

By configuring the shielding heat transfer member 11 with a plurality of parts 12 as described above, and by enabling combinations of wall portions 11b and shielding plates 11a with different shapes, for example, the rotation shown in FIG. Even in the case where the inner surface of the frame 2A is not completely circular, as in the electric machine 20, or in the case where there is a structure 21 that is structurally difficult to avoid, such as a portion where terminals are pulled out, the parts 12 may be formed in a plurality of or different shapes. By combining the above, it is possible to dispose the shielding heat transfer member 11 that shields the space between the coil end 4a and the radiator 8 (not shown) in a substantially annular shape as a whole.

At this time, the parts 12 can be arranged without gaps in the circumferential direction, but gaps may exist between the parts 12 as shown in FIG. This is because, since the radiator 8 rotates, there is little possibility that the same portion of the radiator 8 will continue to be heated by heat radiation from the gap.

Further, in combination with the rotary electric machine 1 of the first embodiment, the shielding member 9 and the shielding heat transfer member 11 can be provided. In this case, if the distance between the coil end 4a and the radiator 8 is relatively short, for example, on the left side of the drawing of the rotary electric machine 1 shown in FIG. If the distance between the end 4a and the radiator 8 is relatively long, the shielding member 9 and the shielding heat transfer member 11 may be provided. For example, in the case of an assembly order in which the rotor 5 and the shaft 6 are inserted into the inner peripheral side of the stator 4 fixed to the frame 2, the radiator 8 is not provided on the front end side in the insertion direction, and the rear end in the insertion direction is installed. The radiator 8 can be easily arranged on one side of the rotor 5 in the axial direction by inserting the rotor 5 with the radiator 8 attached in advance.

Further, in the case where the radiator 8 is provided on one side of both sides in the axial direction and the radiator 8 is not provided on the other side, the shielding heat transfer member 11 is placed on the side on which the radiator 8 is not provided. It can be configured to be provided. As a result, heat is radiated from the coil end 4a via the shielding heat transfer member 11 to the outer surface of the frame 2, and the heat transferred to the shaft 6 can be relatively reduced. It is possible to suppress the influence of the transmitted heat on the member.

While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.

In the drawings, 1 and 10 are rotary electric machines, 2 and 2A are frames, 3, 3A and 3B are brackets, 3a is a flat surface, 4 is a stator, 4a is a coil end, 5 is a rotor, 6 is a shaft, and 7 is a shaft. Bearings, 8, 8A, 8B, 8C are radiators, 8a is a heat radiating surface, 9, 9A, 9B, 9C, 9D, 9E, 9F are shielding members, 11 is shielding heat transfer members, 12A, 12B, 12C, 12D are A part (shielding heat transfer member) is shown.

Claims (4)

a frame housing the stator and rotor;
a bracket that closes the opening of the frame;
a shaft fixed to and rotating with the rotor;
a bearing that rotatably supports the shaft;
a radiator mounted on the shaft between the rotor and the bearing in the axial direction and having a heat radiation surface facing the inner surface of the bracket. A coil end is formed at an axial end of the stator,
2. The electric rotating machine according to claim 1, wherein said radiator is formed to have a size such that an outer edge of said heat radiating surface overlaps an inner edge of said coil end when viewed from the axial direction. A coil end is formed at an axial end of the stator,
3. The electric rotating machine according to claim 1, further comprising a shielding member attached to the coil end side of the heat radiator and blocking at least part of direct heat radiation from the coil end to the heat radiator. A coil end is formed at an axial end of the stator,
It is attached to the frame and positioned between the radiator and the coil end to block at least part of direct heat radiation from the coil end to the radiator, and to block heat received from the coil end. 4. The electric rotating machine according to any one of claims 1 to 3, further comprising a shield heat transfer member that transfers heat to the frame.

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