Static shaft shoulder mechanism of friction stir welding machine

Abstract

The invention discloses a static shaft shoulder mechanism of a friction stir welding machine. The static shaft shoulder mechanism comprises a static shaft shoulder, a stirring head and a sliding bearing. A through hole penetrating through the upper end and the lower end of the static shaft shoulder is formed in the middle of the static shaft shoulder; the stirring head comprises a head part and a stirring main body which are sequentially connected from bottom to top; the lower end of the stirring main body penetrates through the through hole, and a gap is reserved between the outer wall of the stirring main body and the side wall of the through hole; the head part downwards protrudes out of the bottom surface of the static shaft shoulder; the sliding bearing comprises a straight cylindrical bearing main body and a positioning ring connected to the peripheral outer wall of the top of the bearing main body; the bearing main body is mounted in the through hole and sleeves the stirring main body; the outer wall of the bearing main body is attached to the side wall of the through hole, and the inner wall of the bearing main body is attached to the outer wall of the stirring main body; and the positioning ring is connected to the top surface of the static shaft shoulder. By arranging the sliding bearing capable of limiting the stirring head, friction between the stirring head and the static shaft shoulder is prevented, and normal functions and the service life of the static shaft shoulder can be guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of friction stir welding machines, in particular to a static shoulder mechanism of a friction stir welding machine. Background Art

[0002] Static shoulder friction stir welding is a new type of friction stir welding technology. Since the static shoulder does not rotate with the stirring tool during welding, the heat input generated is small. It is suitable for materials with low thermal conductivity. The smoothing effect of the static shoulder can make the weld surface flat and smooth.

[0003] Regarding the static shoulder friction stir welding tool, the authorization announcement number CN109202266B discloses a static shoulder friction stir welding tool that is conducive to discharging seepage material, which specifically discloses a stirring tool and a static shoulder; the stirring tool includes a head, a cylindrical section above the head and a conical section above the cylindrical section, the static shoulder center has a cylindrical step hole for accommodating the stirring tool, the diameter of the upper section of the step hole is greater than the diameter of the lower section, the lower section of the step hole of the static shoulder accommodates the cylindrical section of the stirring tool, the upper section of the step hole of the static shoulder accommodates the conical section of the stirring tool, the lower part of the conical section of the stirring tool has a convex structure, and there is a convex structure between the lower end surface of the convex structure and the step surface of the static shoulder. In the gap, the gap is communicated with the gap between the cylindrical section of the stirring tool and the lower section of the step hole of the static shoulder. The static shoulder is provided with a seepage material discharge hole communicated with the gap. The outer side of the protruding structure is close to but not in contact with the static shoulder. The distance between the two should not affect the movement of the stirring tool and can prevent the upwelling of the seepage material. The gap, the gap and the seepage material discharge hole together form a discharge channel for the seepage material. A step of nearly 90 degrees is processed in the lower section of the cylindrical section of the protruding structure, and a gap with a nearly rectangular longitudinal section is formed between the step surface and the step surface of the static shoulder. The inner side of the nearly rectangular longitudinal section of the gap is flush with the outer side of the cylindrical section above the head of the stirring tool.

[0004] However, there is still room for improvement in the above-mentioned static shoulder friction stir welding tool, for example, since the lower section of the stepped hole on the static shoulder is used to accommodate the cylindrical section of the stirring tool. However, since the stirring tool is subjected to the axial pressure generated by the equipment mechanism and the travel pressure generated during the movement during the rotation, it is easy to cause the center of gravity of the stirring tool to shift backward, resulting in uneven force on the cylindrical section of the stirring tool, and then causing serious friction between the lower section of the stepped hole of the static shoulder shaft and the stirring head during the welding process, and finally causing the lower section of the stepped hole of the static shoulder to be severely worn, resulting in the failure of the static shoulder function and a significant reduction in service life.

[0005] Therefore, it is necessary to improve the existing technology. Summary of the invention

[0006] In view of the problems existing in the above prior art, the purpose of the present invention is to provide a static shoulder mechanism of a friction stir welding machine, which can use a sliding bearing to limit the stirring head so that the center of the stirring head is not easily shifted backward, thereby avoiding friction between the stirring head and the static shoulder, that is, it can ensure the normal function and service life of the static shoulder.

[0007] In order to achieve the above object, the technical solution of the present invention is:

[0008] A static shoulder mechanism of a friction stir welding machine includes a static shoulder, a stirring head and a sliding bearing; a through hole is provided in the middle of the static shoulder and passes through the upper and lower ends of the static shoulder; the stirring head includes a head and a stirring body connected in sequence from bottom to top; the lower end of the stirring body is inserted into the through hole and a gap is left between the outer wall of the stirring body and the side wall of the through hole; the head protrudes downward from the bottom surface of the static shoulder; the sliding bearing includes a straight cylindrical bearing body and a positioning ring connected to the outer walls around the top of the bearing body; the bearing body is installed in the through hole and matchedly sleeved on the stirring body; the outer wall of the bearing body fits with the side wall of the through hole and the inner wall of the bearing body fits with the outer wall of the stirring body; the positioning ring is connected to the top surface of the static shoulder. Through the above arrangement, the sliding bearing can be used to limit the stirring head to prevent the stirring head from rubbing against the side wall of the through hole and causing serious wear of the lower end opening of the through hole, thereby ensuring the normal function and service life of the static shoulder.

[0009] Furthermore, the perforation includes a first cylindrical section, a conical section and a second cylindrical section whose widths decrease successively from top to bottom; the lower end of the stirring body is placed in the second cylindrical section.

[0010] Furthermore, the gap between the first cylindrical section and the stirring body is larger than the gap between the third cylindrical section and the stirring body; the gap between the conical section and the stirring body is larger than the gap between the third cylindrical section and the stirring body.

[0011] Further, the length of the bearing body is smaller than the length of the first cylindrical section.

[0012] Furthermore, a main chip removal hole is provided on the static shaft shoulder, which penetrates the outer wall and the inner wall of the static shaft shoulder and can be used to discharge waste chips; the main chip removal hole is opened close to the lower end of the through hole. The above arrangement can facilitate the discharge of debris.

[0013] Furthermore, a secondary chip removal hole is provided on the static shaft shoulder, which passes through the outer wall and the inner wall of the static shaft shoulder and can be used to discharge waste chips; the secondary chip removal hole is higher than the main chip removal hole. The above arrangement can improve the chip removal effect.

[0014] Furthermore, two secondary chip removal holes are provided and the two secondary chip removal holes are respectively located on both sides of the static shoulder, thereby further enhancing the chip removal effect.

[0015] Furthermore, the sliding bearing is a powder metallurgy sliding bearing.

[0016] Furthermore, the top surface and the bottom surface of the static shoulder are both planes.

[0017] Furthermore, the positioning ring and the top surface of the static shoulder are locked by bolts, so that the sliding bearing can be easily disassembled and assembled.

[0018] The beneficial effects of the present invention are:

[0019] The present invention sets a sliding bearing and utilizes the sliding bearing to limit the stirring head, that is, to correct the center, so that when the stirring head is subjected to the dual pressure of the axial pressure of the equipment head and the travel pressure during movement, the center of the stirring head is not easily shifted backward, thereby avoiding the friction between the stirring head and the side wall of the perforation, which may cause serious wear of the lower end opening of the perforation. That is, this design can keep the function of the static shaft shoulder normal and ensure its service life; at the same time, this design can also avoid the friction with the static shaft shoulder and affect the normal rotation of the stirring head. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The overall structure of the present invention is shown in FIG. Figure 1 ;

[0021] Figure 2 The overall structure of the present invention is shown in FIG. Figure 2 ;

[0022] Figure 3 yes Figure 2 Cross-section along AA;

[0023] Figure 4 It is a schematic structural diagram of the static shoulder of the present invention;

[0024] Figure 5 It is a longitudinal cross-sectional view of the static shoulder of the present invention.

[0025] Reference numerals

[0026] 1. Static shoulder; 11. Perforation; 111. First cylindrical section; 112. Conical section; 113. Second cylindrical section; 12. Primary chip removal hole; 121. Secondary chip removal hole; 13. Outer edge; 2. Stirring head; 21. Head; 22. Stirring body; 3. Sliding bearing; 31. Bearing body; 32. Positioning ring; 4. Gap. DETAILED DESCRIPTION

[0027] The invention is further described below in conjunction with the accompanying drawings and specific embodiments. The following description is only exemplary and does not limit the protection scope of the invention.

[0028] like Figure 1-Figure 5 As shown, a static shoulder mechanism of a friction stir welding machine includes a static shoulder 1, a stirring head 2 and a sliding bearing 3; a through hole 11 is provided in the middle of the static shoulder 1 and passes through the upper and lower ends of the static shoulder 1; the stirring head 2 includes a head 21 and a stirring body 22 which are connected in sequence from bottom to top; the lower end of the stirring body 22 is penetrated in the through hole 11 and a gap 4 is left between the outer wall of the stirring body 22 and the side wall of the through hole 11; the head 21 protrudes downward from the bottom surface of the static shoulder 1; the sliding bearing 3 includes a straight cylindrical bearing body 31 and a positioning ring 32 connected to the outer walls around the top of the bearing body 31; the bearing body 31 is installed in the through hole 11 and is matchedly sleeved on the stirring body 22; the outer wall of the bearing body 31 is in contact with the side wall of the through hole 11 and the inner wall of the bearing body 31 is in contact with the outer wall of the stirring body 22; the positioning ring 32 is connected to the top surface of the static shoulder 1.

[0029] Therefore, the present invention sets a sliding bearing 3 and utilizes the sliding bearing 3 to limit the stirring head 2, that is, to correct the center, so that when the stirring head 2 is subjected to the dual pressure of the axial pressure of the equipment head and the travel pressure during movement, the center of the stirring head 2 is not easily shifted backward, thereby avoiding the friction between the stirring head 2 and the side wall of the through hole 11, which may cause serious wear of the lower end opening of the through hole 11, that is, this design can keep the function of the static shaft shoulder 1 normal and ensure its service life; at the same time, this design can also avoid the friction with the static shaft shoulder 1 and affect the normal rotation of the stirring head 2.

[0030] like Figure 3 As shown, the specific shape of the through hole 11 can be set as follows: the through hole 11 includes a first cylindrical section 111, a conical section 112, and a second cylindrical section 113, the widths of which decrease from top to bottom; the lower end of the stirring body 22 is placed in the second cylindrical section 113. However, those skilled in the art should know that the shape of the through hole 11 can also be deformed accordingly, as long as a certain gap 4 is maintained between its side wall and the stirring body 22.

[0031] like Figure 3 As shown, specifically, for the stirring body 22, it can also be divided into a first stirring cylindrical section (not marked in the figure), a stirring conical section (not marked in the figure) and a second stirring cylindrical section (not marked in the figure) from top to bottom, wherein the second stirring cylindrical section is placed in the second cylindrical section 113 of the perforation 11.

[0032] like Figure 3As shown, specifically, the gap 4 between the first cylindrical section 111 and the stirring body 22 is larger than the gap 4 between the third cylindrical section and the stirring body 22 ; the gap 4 between the conical section 112 and the stirring body 22 is larger than the gap 4 between the third cylindrical section and the stirring body 22 .

[0033] The size of the gap 4 should be set within an appropriate range. If the gap is too small, there will be friction between the stirring head 2 and the static shoulder 1, which will not only easily damage the static shoulder 1 but also affect the normal rotation of the stirring head 2; if the gap is too large, when the stirring head 2 rotates in the material, too much material will easily flow into the gap 4, which will not only easily affect the normal rotation of the stirring head 2 but also easily cause the center of the stirring head 2 to shift and eventually cause the stirring head 2 to wear, thereby affecting the quality of welding.

[0034] like Figure 3 As shown, specifically, the length of the bearing body 31 is less than the length of the first cylindrical section 111. Of course, those skilled in the art should know that the length of the bearing body 31 can be appropriately extended or shortened according to actual needs, which is not specifically limited here.

[0035] like Figure 1 , Figure 4 and Figure 5 As shown, preferably, a main chip discharge hole 12 is provided on the static shoulder 1, which penetrates the outer wall and the inner wall of the static shoulder 1 and can be used to discharge waste chips; in addition, the main chip discharge hole 12 is open near the lower end of the through hole 11. For the main chip discharge hole 12, when the stirring body 22 is stirring and rubbing, the generated debris (such as aluminum chips) first passes through the gap 4 into the through hole 11, and then is discharged outward through the main chip discharge hole 12.

[0036] like Figure 1 , Figure 4 and Figure 5 As shown, in order to enhance the chip removal effect, a secondary chip removal hole 121 is also provided on the static shaft shoulder 1, which penetrates the outer wall and the inner wall of the static shaft shoulder 1 and can be used to discharge waste chips; the secondary chip removal hole 121 is located higher than the main chip removal hole 12. After the secondary chip removal hole 121 is provided, the chips that cannot be completely discharged by the main chip removal hole 12 will pass through the secondary chip removal hole 121 again for auxiliary chip removal, that is, the cooperation of the two chip removal holes ensures the chip removal effect.

[0037] like Figure 1 , Figure 4 and Figure 5 As shown, in order to further enhance the chip removal effect, two secondary chip removal holes 121 are provided and the two secondary chip removal holes 121 are symmetrically located on both sides of the static shoulder 1. At the same time, the size of the secondary chip removal hole 121 can be set larger than the size of the primary chip removal hole 12.

[0038] Preferably, the sliding bearing 3 can be a powder metallurgy sliding bearing. Powder metallurgy sliding bearings have the advantages of self-lubricating performance, high precision, low production cost, environmental friendliness, etc., so that they can be widely used in various equipment in various industries, including stir friction welding machines, and their various advantages can make them show unique technical advantages and economic benefits.

[0039] like Figure 1-Figure 3 As shown, in this embodiment, the top surface and the bottom surface of the static shoulder 1 are both planes. Therefore, since the top surface of the static shoulder 1 is a plane, it can be stably connected to the positioning ring 32.

[0040] Specifically, the locating ring 32 can be locked with the top surface of the static shaft shoulder 1 by bolts, which makes the sliding bearing easy to disassemble and assemble. In addition, if necessary, for the sliding bearing 3, the locating ring 32 can also be arranged in a manner of directly abutting against the static shaft shoulder 1.

[0041] like Figure 1-Figure 5 As shown, specifically, a circle of outer edge 13 is provided on the outer wall around the upper end of the static shaft shoulder 1, so that the static shaft shoulder 1 can be conveniently connected with other components.

[0042] The present invention is not limited to the above-mentioned embodiments. If various changes or modifications to the present invention do not depart from the spirit and scope of the present invention, and if these changes and modifications fall within the scope of the claims and equivalent technologies of the present invention, the present invention is also intended to include these changes and modifications.

Claims

1. A static shoulder mechanism of a friction stir welding machine, characterized in that: It comprises a static shoulder, a stirring head and a sliding bearing; a through hole penetrating the upper and lower ends of the static shoulder is arranged in the middle of the static shoulder; the stirring head comprises a head and a stirring body connected in sequence from bottom to top; the lower end of the stirring body is inserted into the through hole and a gap is left between the outer wall of the stirring body and the side wall of the through hole; the head protrudes downward from the bottom surface of the static shoulder; the sliding bearing comprises a straight cylindrical bearing body and a positioning ring connected to the outer walls around the top of the bearing body; the bearing body is installed in the through hole and matchedly sleeved on the stirring body; the outer wall of the bearing body is fitted with the side wall of the through hole and the inner wall of the bearing body is fitted with the outer wall of the stirring body; the positioning ring is connected to the top surface of the static shoulder; The sliding bearing can be used to limit the stirring head to prevent the stirring head from rubbing against the side wall of the through hole and causing deformation of the lower end opening of the through hole, thereby ensuring the welding effect and service life of the static shoulder.

2. The static shoulder mechanism of the friction stir welding machine according to claim 1, characterized in that: The perforation includes a first cylindrical section, a conical section and a second cylindrical section, the widths of which decrease from top to bottom; the lower end of the stirring body is placed in the second cylindrical section.

3. The static shoulder mechanism of the friction stir welding machine according to claim 2, characterized in that: The gap between the first cylindrical section and the stirring body is larger than the gap between the third cylindrical section and the stirring body; the gap between the conical section and the stirring body is larger than the gap between the third cylindrical section and the stirring body.

4. The static shoulder mechanism of the friction stir welding machine according to claim 2, characterized in that: The length of the bearing body is smaller than the length of the first cylindrical section.

5. The static shoulder mechanism of the friction stir welding machine according to claim 1, characterized in that: A main chip removal hole is also provided on the static shaft shoulder, which penetrates the outer wall and the inner wall of the static shaft shoulder and can be used to discharge waste chips; the main chip removal hole is open close to the lower end of the through hole.

6. The static shoulder mechanism of the friction stir welding machine according to claim 5, characterized in that: A secondary chip removal hole is also provided on the static shaft shoulder, which penetrates the outer wall and the inner wall of the static shaft shoulder and can be used to discharge waste chips; the secondary chip removal hole is higher than the main chip removal hole.

7. The static shoulder mechanism of the friction stir welding machine according to claim 6, characterized in that: The secondary main chip removal holes are provided with two, and the two secondary main chip removal holes are respectively located on both sides of the static shaft shoulder.

8. The static shoulder mechanism of the friction stir welding machine according to claim 1, characterized in that: The sliding bearing is a powder metallurgy sliding bearing.

9. The static shoulder mechanism of the friction stir welding machine according to claim 1, characterized in that: The top surface and the bottom surface of the static shoulder are both planes.

10. The static shoulder mechanism of the friction stir welding machine according to claim 1, characterized in that: The positioning ring and the top surface of the static shoulder are locked by bolts.

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