JP2021186858A - Liquid-cooled jacket manufacturing method - Google Patents

Abstract

To provide a liquid-cooled jacket manufacturing method that can enhance joint strength of a liquid-cooled jacket and manufacture the jacket at low cost.SOLUTION: The liquid-cooled jacket manufacturing method includes a main jointing step in which a stirring pin F2 of a rotating tool F is inserted first into a surface 3a of a sealing body 3, and a tip surface of a protrusion part F4 is made to contact a peripheral wall part 11 and to relatively go around the peripheral wall part 11 at a predetermined depth along a butting part J1 with a bottom surface F1a of a shoulder part F1 contacted with the surface 3a of the sealing body 3 to friction-stir the butting part J1, while contacting a flat surface F3 of the stirring pin F2 with only the sealing body 3. In the main jointing step, a jacket main body 2 and the sealing body 3 are rotated or moved parallel using a pair of holding parts 22 to friction-stir the jacket main body 2 and the sealing body 3, while making the holding parts 22 press and hold a bottom part 10 of the jacket main body 2 and the surface 3a of the sealing body 3 from both outsides thereof.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for manufacturing a liquid-cooled jacket.

A method for manufacturing a liquid-cooled jacket using friction stir welding is performed. For example, Patent Document 1 discloses a method for manufacturing a liquid-cooled jacket in which a jacket body and a sealing body that seals an opening of the jacket body are joined by friction stir welding. In the method for manufacturing the liquid-cooled jacket, a rotating tool is inserted vertically from the side surface of the jacket body and the sealing body, and the jacket body is rotated around the jacket body to perform friction stir welding.

Japanese Unexamined Patent Publication No. 2018-69322

In the invention according to Patent Document 1, in order to rotate the rotating tool around the jacket body with the rotating tool and the side surface of the jacket body perpendicular to each other, the jig for clamping the jacket body and the sealing body is the rotating tool. It hinders the movement of. As a result, for example, it is necessary to divide the area into friction stir welding, which causes a problem that the work man-hours increase and the manufacturing cost increases. It is also desired that the liquid-cooled jacket further enhances the bonding strength between metal members.

From such a viewpoint, it is an object of the present invention to provide a method for manufacturing a liquid-cooled jacket, which can increase the bonding strength of the liquid-cooled jacket and can be manufactured at low cost.

In order to solve the above problems, the present invention comprises a jacket body having a bottom portion and a peripheral wall portion rising from the peripheral edge of the bottom portion, and a sealing body for sealing the opening of the jacket body, and the jacket body and the jacket body. A method for manufacturing a liquid-cooled jacket for joining the sealing body by frictional stirring, the rotary tool used for frictional stirring includes a shoulder portion and a stirring pin hanging from the center of the bottom surface of the shoulder portion. The stirring pin has a tapered shape, has a flat surface perpendicular to the rotation center axis at its tip, and has a protrusion protruding from the flat surface, and the sealing body is attached to the jacket body. The mounting step of forming the butt portion by abutting the end surface of the peripheral wall portion and the back surface of the sealing body by mounting, and the stirring pin of the rotating tool are inserted from the surface of the sealing body. The flat surface of the stirring pin was brought into contact with only the sealing body, the tip surface of the protrusion was brought into contact with the peripheral wall portion, and the bottom surface of the shoulder portion was brought into contact with the surface of the sealing body. In the state, the main joining step of circling the butt portion relatively around the peripheral wall portion at a predetermined depth along the butt portion and rubbing and stirring the butt portion is included. While pressing and holding the bottom portion and the surface of the sealing body from both outer sides with a pair of holding portions, the jacket main body and the sealing body are rotated or moved in parallel using the holding portions to rotate or parallel move the jacket main body. It is characterized in that and the sealed body are rubbed and stirred.

According to such a manufacturing method, since the jacket body and the sealing body are rotated or translated in a state where the jacket body and the sealing body are held by the pair of holding portions, it is not necessary to perform the clamping operation a plurality of times. In addition, the holding portion and the rotating tool do not interfere with each other during the main joining process. That is, the jig for positioning the jacket body and the sealing body does not hinder the movement of the rotating tool. As a result, the work man-hours can be reduced, and incidental equipment such as a device for driving the rotary tool can be simplified, and the liquid-cooled jacket can be manufactured at low cost. Further, in this joining step, since the plastic fluid material can be pressed by the bottom surface of the shoulder portion, the generation of burrs can be suppressed.

Further, since the flat surface of the stirring pin is brought into contact with only the sealing body and the tip surface of the protruding portion is brought into contact with the peripheral wall portion for frictional stirring, the plasticity wound around the protruding portion of the stirring pin is formed. The fluid material is pressed by a flat surface, and the oxide film at the butt portion can be reliably separated. As a result, the joint strength of the butt portion can be increased.

Further, a plurality of fins are formed on the back surface of the sealed body, and in the main joining step, the tips of at least a part of the fins of the plurality of fins are in contact with the bottom of the jacket body. It is preferable to frictionally stir the jacket body and the sealing body.

According to such a manufacturing method, the tip of the fin comes into contact with the bottom of the jacket body, so that the deformation of the sealed body can be suppressed.

Further, in the main joining step, the stirring pin is rotated at a predetermined rotation speed to perform frictional stirring, and when the stirring pin is pulled out in the main joining step, the rotation speed is gradually increased from the predetermined rotation speed. However, it is preferable to move the stirring pin relative to the end position.

Further, in the main joining step, the stirring pin is rotated at a predetermined rotation speed to perform frictional stirring, and when the stirring pin is inserted in the main joining step, the stirring is performed at a speed higher than the predetermined rotation speed. It is preferable to insert the stirring pin while rotating the pin and gradually reducing the rotation speed.

According to such a manufacturing method, a small pressing force at the time of inserting or detaching the rotating tool can be supplemented by the rotating speed, so that friction stir welding can be preferably performed.

According to the method for manufacturing a liquid-cooled jacket according to the present invention, the bonding strength of the liquid-cooled jacket can be increased and the liquid-cooled jacket can be manufactured at low cost.

It is a side view which shows the rotation tool which concerns on embodiment of this invention. It is an exploded perspective view of the liquid-cooled jacket which concerns on this embodiment. It is sectional drawing which shows the mounting process of the manufacturing method of the liquid-cooled jacket which concerns on this embodiment. It is a perspective view which shows the holding process of the manufacturing method of the liquid-cooled jacket which concerns on this embodiment. It is a perspective view which shows the friction stir welding process of the manufacturing method of the liquid-cooled jacket which concerns on this embodiment. It is sectional drawing which shows the friction stirring process of the manufacturing method of the liquid-cooled jacket which concerns on this embodiment. It is a perspective view which shows after the friction stir welding process of the manufacturing method of the liquid-cooled jacket which concerns on this embodiment.

An embodiment of the present invention will be described with reference to the drawings as appropriate. The present invention is not limited to the following embodiments. In addition, some or all of the components in each embodiment can be combined as appropriate. In the following description, the "front surface" means the opposite surface of the "back surface".

First, as shown in FIG. 1, the rotation tool F used in the method for manufacturing a liquid-cooled jacket according to the present embodiment will be described. The rotary tool F is made of, for example, tool steel, and is composed of a shoulder portion F1 and a stirring pin F2. The bottom surface F1a of the shoulder portion F1 is a portion that holds down the plastically fluidized metal. The shoulder portion F1 has a columnar shape.

The stirring pin F2 hangs down from the center of the bottom surface F1a of the shoulder portion F1 and is coaxial with the shoulder portion F1. The stirring pin F2 has a tapered shape as it is separated from the shoulder portion F1. At the tip of the stirring pin F2, a flat flat surface F3 that is perpendicular to the rotation center axis C and is flat is formed. The protrusion F4 is a portion of the flat surface F3 that protrudes downward from the center. The shape of the protrusion F4 is not particularly limited, but is, for example, a columnar shape. A stepped portion is formed by the flat surface F3 and the side surface of the protruding portion F4.

A spiral groove is engraved on the outer peripheral surface of the stirring pin F2. When rotating the rotation tool F clockwise, the spiral groove is carved counterclockwise from the base end to the tip end. When rotating the rotation tool F counterclockwise, the spiral groove is carved clockwise from the base end to the tip end. In this way, the metal plastically fluidized by friction stir welding is guided to the spiral groove and moves to the tip side of the stirring pin F2. As a result, the amount of metal overflowing from the metal member to be joined (jacket body 2, sealing body 3) can be reduced.

The rotation tool F may be attached to a friction stirring device that can move in the horizontal direction and the vertical direction, or may be attached to a robot arm having a rotation driving means such as a spindle unit at the tip.

As shown in FIG. 2, the liquid-cooled jacket 1 according to the present embodiment is composed of a jacket body 2 and a sealing body 3. The liquid-cooled jacket 1 is a device that circulates a fluid inside to cool an arranged heating element. The jacket body 2 and the sealing body 3 are integrated by friction stir welding.

The jacket body 2 is mainly composed of a bottom portion 10 and a peripheral wall portion 11. The jacket body 2 may be any metal (aluminum, aluminum alloy, magnesium, magnesium alloy, copper, copper alloy, titanium, titanium alloy, etc.) that can be agitated by friction, but in this embodiment, it is made of an aluminum alloy.

The bottom portion 10 is a plate-shaped member having a rectangular shape. The peripheral wall portion 11 is a wall portion that rises in a rectangular frame shape from the peripheral edge portion of the bottom portion 10. The corner of the peripheral wall portion 11 may be a right angle, but in the present embodiment, a round chamfering process is performed. A recess 13 is formed in the bottom portion 10 and the peripheral wall portion 11. Although the jacket body 2 of the present embodiment is integrally formed, for example, the peripheral wall portion 11 may be divided and joined by a sealing member to be integrated.

The sealing body 3 is a plate-shaped member that seals the opening of the jacket body 2. The corners of the sealing body 3 may be right angles, but in the present embodiment, round chamfering is performed. The sealing body 3 is not particularly limited as long as it is a metal capable of friction stir welding, but in the present embodiment, it is formed mainly containing an aluminum alloy.

A plurality of plate-shaped fins 31 perpendicular to the back surface 3b are formed on the back surface 3b of the sealing body 3. The height dimension of the fin 31 is substantially the same as the height dimension of the peripheral wall portion 11.

The sealing body 3 on which the fins 31 are formed may be formed by joining a plurality of fins 31 to a plate-shaped member by brazing or the like, or may be formed by cutting one elemental material. .. In this embodiment, a plurality of fins 31 are provided on the sealing body 3, but a plurality of fins 31 may be provided on the surface 10a of the bottom portion 10 of the jacket body 2. Further, the fin 31 may be omitted.

Next, a method for manufacturing the liquid-cooled jacket according to the present embodiment will be described. In the method for manufacturing a liquid-cooled jacket according to the present embodiment, a preparation step, a mounting step, and a main joining step are performed.

As shown in FIG. 2, the preparation step is a step of preparing the jacket main body 2 and the sealing body 3. The jacket body 2 and the sealing body 3 are not particularly limited in terms of manufacturing method, but the jacket body 2 is molded by die casting, for example. The sealing body 3 is formed, for example, by cutting a raw material.

As shown in FIG. 3, the mounting step is a step of mounting the sealing body 3 on the jacket main body 2. By the mounting step, the end surface 11a of the peripheral wall portion 11 and the back surface 3b of the sealing body 3 are abutted to form the abutting portion J1. The butt portion J1 is formed in a rectangular shape in a plan view along the periphery of the sealing body 3. The outer surface 11c of the peripheral wall portion 11 and the side surface 3c of the sealing body 3 are flush with each other in the circumferential direction. Further, the tip of the fin 31 abuts on or faces the surface 10a of the bottom portion 10 with a slight gap. The jacket body 2 and the sealing body 3 may be temporarily joined by welding, friction stir welding, or the like.

As shown in FIGS. 4 to 7, this joining step is a step of friction stir welding the butt portion J1 using the rotation tool F. In this joining step, a holding step and a friction stir welding step are performed. In the holding step, the jacket body 2 and the sealing body 3 are pressed from both outsides and held by a holding device (jig) provided with a pair of holding portions 22. In the present embodiment, an intermediate plate 21 is interposed between the holding portion 22 and the bottom portion 10 and between the holding portion 22 and the sealing body 3, respectively. The holding portion 22 has a columnar shape, and its end faces are in surface contact with the intermediate plates 21 and 21, respectively. By providing the intermediate plate 21, the pressing force of the holding portion 22 can be dispersed to reliably hold the jacket body 2 and the sealing body 3. The intermediate plate 21 may be omitted.

The holding portion 22 of the holding device, the jacket body 2 and the sealing body 3 rotate or move in parallel in synchronization with each other. That is, the sandwiching device rotates the jacket body 2 and the sealing body 3 in the circumferential direction while the bottom portion 10 of the jacket body 2 and the surface 3a of the sealing body 3 are pressed and sandwiched by the holding portions 22 and 22, respectively. At the same time, it can be linearly moved up and down, left and right, and front and back.

In this joining step, first, as shown in FIGS. 4 and 5, a holding step of holding the jacket body 2 and the sealing body 3 is performed, and the jacket body 2 and the sealing body 3 are held by using a holding device (jig). To hold. Then, the holding device is operated to insert the rotary tool F that rotates clockwise into the start position SP1 set on the surface 3a of the sealing body 3 to perform the friction stirring step. In the friction stir welding step, friction stir welding is continuously performed between the closet section, the main section, and the detachment section.

The closet section is a section from the start position SP1 set on the surface 3a of the sealing body 3 to the intermediate point S1 also set on the surface 3a of the sealing body 3. This section is set on the surface 3a of the sealing body 3 after moving around the peripheral wall portion 11 from the intermediate point S1 and moving along the outer edge portion of the surface 3a of the sealing body 3 and passing through the intermediate point S1. It is a section up to the intermediate point S2. The detachment section is a section from the intermediate point S2 to the end position EP1 set on the surface 3a of the sealing body 3. The intermediate points S1 and S2 are set at positions corresponding to the butt portion J1 on the surface 3a of the sealing body 3 so as to be separated from each other. Further, the start position SP1 and the end position EP1 are set inside the surface 3a of the sealing body 3 from the position corresponding to the butt portion J1.

In the closet section, the rotation center axis C of the rotation tool F is arranged so as to be perpendicular to the start position SP1, and the stirring pin F2 is gradually pushed in until it reaches a predetermined depth while moving relative to the intermediate point S1. go. When the rotation tool F reaches the intermediate point S1, the section shifts to this section as it is. A plasticized region W1 is formed in the movement locus of the rotation tool F. When shifting the rotation tool F from the closet section to this section, move the rotation tool F in a straight line or arc shape in a plan view so that the rotation tool F does not stop or the movement speed does not decrease in the middle. Is preferable.

In this section, the rotation tool F is used while maintaining a predetermined depth while keeping the rotation center axis C of the rotation tool F and the surface 3a of the sealing body 3 and the end surface 11a of the peripheral wall portion 11 perpendicular to each other. The outer edge portion of the sealing body 3 is moved relative to the outer edge portion of the surface 3a so as to go around the outer edge portion. Here, the "predetermined depth" means the depth at which the stirring pin F2 of the rotation tool F is inserted from the intermediate point S1 to the intermediate point S2 in this section. As shown in FIG. 6, in the present embodiment, the bottom surface F1a of the shoulder portion F1 is brought into contact with the surface 3a of the sealing body 3, and the flat surface F3 of the stirring pin F2 is in contact with only the sealing body 3 while protruding. A predetermined depth is set so that the tip surface of the portion F4 comes into contact with the peripheral wall portion 11. At the corners of the jacket body 2 and the sealing body 3, the rotating tool F is relatively moved while rotating the holding portions 22 and 22 (jacket body 2 and the sealing body 3). Further, in the straight portion of the jacket main body 2 and the sealing body 3, the rotating tool F is relatively moved while the holding portion 22 (jacket main body 2 and the sealing body 3) is linearly moved.

In this section, the stirring pin F2 is inserted from the side of the surface 3a of the sealing body 3 to the butt portion J1, and the stirring pin F2 of the rotating tool F is brought into contact with the peripheral wall portion 11 and the sealing body 3, and the flat surface F3. The butt portion J1 is in a state where the tip surface of the protrusion F4 is in contact with the peripheral wall portion 11 and the bottom surface F1a of the shoulder portion F1 is in contact with the surface 3a of the seal body 3 while contacting only the sealing body 3. Is rubbed and agitated. Further, in this section, when the start end and the end of the plasticized region W1 overlap at the position corresponding to the butt portion J1 of the surface 3a of the sealing body 3 and the rotation tool F reaches the intermediate point S2, the detachment section is used as it is. Move to. When shifting the rotation tool F from this section to the departure section, move the rotation tool F in a straight line or arc shape in a plan view so that the rotation tool F does not stop or the movement speed does not decrease in the middle. Is preferable. In the detachment section, as shown in FIG. 7, the stirring pin F2 is gradually pulled out while moving relative to the end position EP1 from the intermediate point S2, and is detached at the end position EP1.

According to the method for manufacturing a liquid-cooled jacket according to the present embodiment described above, the jacket body 2 and the sealing body 3 are rotated or parallel while the jacket main body 2 and the sealing body 3 are held by the pair of holding portions 22. Since it is moved, it is not necessary to perform the clamping work multiple times. That is, after the jacket body 2 and the sealing body 3 are held by the holding portions 22 and 22, friction stir welding can be continuously performed from the start position SP1 to the end position EP1.

Further, according to the present embodiment, the holding portion 22 and the rotary tool F do not interfere with each other during the main joining process. That is, the jig for positioning the jacket body 2 and the sealing body 3 does not hinder the movement of the rotation tool F. As a result, the work man-hours can be reduced, and incidental equipment such as a device for driving the rotary tool F can be simplified, and the liquid-cooled jacket 1 can be manufactured at low cost.

Further, in this joining step, friction stirring is performed in a state where the bottom surface F1a of the shoulder portion F1 is in contact with the surface 3a of the sealing body 3. As a result, the plastic fluid material can be pressed by the bottom surface F1a of the shoulder portion F1, so that the generation of burrs can be suppressed.

Further, according to the present embodiment, the flat surface F3 of the stirring pin F2 is in contact with only the sealing body 3, and the tip surface of the protrusion F4 is in contact with the peripheral wall portion 11. As a result, the plastic fluid material wound up around the protrusion F4 of the stirring pin F2 is pressed by the flat surface F3, so that the oxide film of the butt portion J1 can be reliably separated. As a result, the joint strength of the butt portion J1 can be increased.

Further, in the present embodiment, a plurality of fins 31 are formed on the back surface 3b of the sealing body 3, and in the present joining step, at least a part of the tips of the plurality of fins 31 are attached to the bottom portion 10 of the jacket body 2. The jacket body 2 and the sealing body 3 are rubbed and agitated in the state of being in contact with each other. As a result, the tip of the fin 31 comes into contact with the bottom portion 10 of the jacket body 2, so that the deformation of the sealing body 3 can be suppressed. When a plurality of fins 31 are provided on the surface 10a of the bottom 10 of the jacket body 2, at least a part of the tips of the plurality of fins 31 are brought into contact with the back surface 3b of the sealing body 3 in this joining step. In this state, the jacket body 2 and the sealing body 3 are rubbed and stirred. As a result, the tip of the fin 31 comes into contact with the back surface 3b of the sealing body 3, so that the deformation of the sealing body 3 can be suppressed.

Here, the start position SP1 may be set at a position corresponding to the butt portion J1 on the surface 3a of the sealing body 3, and the rotation tool F may be vertically inserted to perform friction stir welding. Excessive frictional heat is generated at the start position SP1, which may result in poor joining. On the other hand, as in the present embodiment, the start position SP1 is set inside the position corresponding to the butt portion J1 of the surface 3a of the sealing body 3, and the stirring pin F2 is relatively moved toward the butt portion J1. By gradually pushing in, it is possible to prevent the frictional heat from becoming excessive on the butt portion J1.

Similarly, the end position EP1 may be set at a position corresponding to the butt portion J1 on the surface 3a of the sealing body 3, and the rotation tool F may be vertically detached at the end position EP1, but this form ends. Excessive frictional heat is generated at the position EP1, which may result in poor joining. On the other hand, as in the present embodiment, the end position EP1 is set inside the position corresponding to the butt portion J1 of the surface 3a of the sealing body 3, and the stirring pin F2 is gradually moved from the butt portion J1. By pulling it out, it is possible to prevent the frictional heat from becoming excessive on the butt portion J1.

Further, in this joining step, since the start end and the end end of the plasticized region W1 are overlapped at the position corresponding to the butt portion J1 of the surface 3a of the sealing body 3, the airtightness and the watertightness can be improved. ..

Further, in this joining step, the rotation speed of the rotation tool F may be constant or variable. In the intrusion section of the main joining step, if the rotation speed of the rotation tool F at the start position SP1 is V1 and the rotation speed of the rotation tool F in this section is V2, V1> V2 may be satisfied. The rotation speed V2 is a predetermined constant rotation speed in this section. That is, at the start position SP1, the rotation speed may be set high, and the rotation speed may be gradually reduced in the closet section to shift to the main section.

Further, if the rotation speed of the rotation tool F in this section is V2 and the rotation speed of the rotation tool F at the end position EP1 is V3 in the detachment section of the main joining step, V3> V2 may be satisfied. That is, after shifting to the detachment section, the rotation tool F may be detached from the sealing body 3 while gradually increasing the rotation speed toward the end position EP1. By setting as described above when the rotary tool F is pushed into or detached from the sealing body 3, the small pressing force in the indentation section or the detaching section can be supplemented by the rotation speed. Therefore, friction stir welding can be preferably performed.

Although the embodiments of the present invention have been described above, the design can be appropriately changed within a range not contrary to the gist of the present invention. For example, in this joining step, the position of the rotary tool F is set so as not to be displaced with respect to the friction stir welding device, and the holding portions 22 and 22 (jacket body 2 and sealing body 3) are moved to perform friction stir welding. You may. Further, for example, when the rotary tool F is attached to the robot arm, both the robot arm and the holding portions 22 and 22 (jacket body 2 and sealing body 3) may be moved to perform friction stir welding. .. Further, all the fins 31 do not have to have a constant height, and at least a part of the fins 31 may be brought into contact with the front surface 10a of the bottom portion 10 or the back surface 3b of the sealing body 3.

Further, in the present embodiment, the start position SP1 and the end position EP1 are set inside the butt portion J1, but they may be set on the surface 3a of the sealing body 3 corresponding to the butt portion J1. In this case, the rotary tool F may be gradually pushed in while being relatively moved on the surface 3a of the sealing body 3 corresponding to the butt portion J1. Further, the rotating tool F may be gradually pulled out and detached while being relatively moved on the surface 3a of the sealing body 3 corresponding to the butt portion J1. By doing so, it is possible to prevent the frictional heat from becoming excessive at one point on the surface 3a of the sealing body 3 corresponding to the butt portion J1.

1 Liquid-cooled jacket 2 Jacket body 3 Sealing body 10 Bottom 11 Peripheral wall part 11a End face 22 Holding part F Rotating tool F1 Shoulder part F2 Stirring pin F3 Flat surface F4 Protrusion part J1 Butt part SP1 Start position EP1 End position W1 Plasticization area

Claims (4)

A liquid that is composed of a jacket body having a bottom portion and a peripheral wall portion rising from the peripheral edge of the bottom portion and a sealing body that seals an opening of the jacket body, and joins the jacket body and the sealing body by friction stir welding. It ’s a method of manufacturing a cold jacket.
The rotary tool used for friction stir is provided with a shoulder portion and a stirring pin that hangs from the center of the bottom surface of the shoulder portion.
The stirring pin has a tapered shape, has a flat surface perpendicular to the center axis of rotation at its tip, and has a protrusion protruding from the flat surface.
A mounting step of forming a butt portion by mounting the sealing body on the jacket body so that the end surface of the peripheral wall portion and the back surface of the sealing body are abutted against each other.
The stirring pin of the rotating tool is inserted from the surface of the sealing body, and the flat surface of the stirring pin is brought into contact with only the sealing body, while the tip surface of the protrusion is in contact with the peripheral wall portion. In addition, the bottom surface of the shoulder portion is brought into contact with the surface of the sealing body, and the butt portion is rubbed and agitated by making a relative circumference around the peripheral wall portion at a predetermined depth along the butt portion. Including the main joining process
In the main joining step, the bottom of the jacket body and the surface of the sealing body are pressed and held by a pair of holding portions from both outer sides, and the jacket body and the sealing body are held by using the holding portions. A method for manufacturing a liquid-cooled jacket, which comprises rotating or translating the jacket body and frictionally stirring the jacket body and the sealing body. A plurality of fins are formed on the back surface of the sealing body.
The claim is characterized in that, in the main joining step, the jacket body and the sealing body are frictionally agitated in a state where the tips of at least a part of the fins of the plurality of fins are in contact with the bottom of the jacket body. Item 2. The method for manufacturing a liquid-cooled jacket according to Item 1. In the main joining step, the rotary tool is rotated at a predetermined rotation speed to perform frictional stirring.
The liquid-cooled jacket according to claim 1 or 2, wherein when the stirring pin is pulled out in the main joining step, the stirring pin is moved to the end position while gradually increasing the rotation speed from the predetermined rotation speed. Production method. In the main joining step, the rotary tool is rotated at a predetermined rotation speed to perform frictional stirring.
When inserting the stirring pin in the main joining step, the stirring pin is inserted in a state of being rotated at a speed higher than the predetermined rotation speed, and the stirring pin is inserted while gradually lowering the rotation speed. The method for manufacturing a liquid-cooled jacket according to any one of claims 1 to 3, wherein the liquid-cooled jacket is characterized.

Images