Friction stir welding withdrawing main shaft

Abstract

The friction stir welding pumpback spindle comprises an electric spindle unit and a pumpback shaft unit, the electric spindle unit is arranged at the upper end of the stirring spindle unit, a stator component and a rotor component are installed in the electric spindle unit, and the pumpback shaft unit is installed in a hollow cavity in a rotating shaft. Bearings are arranged at the upper and lower parts of the rotating shaft for supporting rotation; pressure sensors are installed on the circumference of the lower end face of the rotating shaft. According to the friction stir welding pumpback spindle, a pumpback unit is arranged in the friction stir welding pumpback spindle, rotary motion of an electric spindle is converted into axial linear motion of a pumpback shaft, axial reciprocating motion of the pumpback shaft is achieved through control of a driver, and pumpback of a stirring needle is further driven; pressure sensors are installed on the end faces of the stirring main shaft unit and the electric main shaft unit adjacent to the two end faces of the shaft shoulder of the pumpback shaft, the axial displacement stroke of the pumpback shaft is controlled, pressure signals are transmitted in time, and it is guaranteed that the normal pumpback force of the friction stir welding main shaft meets the requirements of different welding working conditions.

Description

Technical Field

[0001] The utility model belongs to the technical field of welding, in particular to a friction stir welding retraction spindle. Background Art

[0002] To eliminate the "keyhole" problem that occurs during welding, current friction stir welding spindles typically feature a retraction mechanism. This mechanism gradually retracts the needle while rotating while welding, simultaneously plastically extruding the workpiece to eliminate the "keyhole" left behind during welding. However, there's no accurate measurement of the retraction pressure, and the retraction mechanism is complex, making it inconvenient to manufacture. Summary of the Invention

[0003] In view of the shortcomings and defects of the existing welding spindle technology, the utility model provides a stir friction welding retraction spindle. The retraction spindle rotation adopts the structural setting of the electric spindle unit. The retraction spindle unit is arranged inside the electric spindle. The rotational motion of the electric spindle unit is converted into axial linear motion of the retraction spindle unit through the action of the retraction shaft unit. A pressure sensor is arranged on the adjacent end face to transmit the pressure signal during the movement, control the retraction force, and adapt to the needs of different welding working conditions.

[0004] The technical solution adopted by the present invention is: a stir friction welding retraction spindle, including an electric spindle unit and a retraction shaft unit, the electric spindle unit is arranged at the upper end of the stirring spindle, and the retraction shaft unit is arranged and installed in the internal cavity of the electric spindle unit; further, pressure sensors are arranged and installed on the axial opposite surfaces of the stirring spindle and the retraction spindle.

[0005] The electric spindle includes a rotating shaft, a sealing ring, an end cover, a shell, a stator component, a rotor component, a bearing seat, a positioning seat, an encoder, a protective sleeve, a bearing, and a bearing group. The rotating shaft is arranged to have a stepped hollow structure, a larger hollow cavity is arranged at the lower end of the rotating shaft, and a retraction shaft unit is arranged on the inner wall of the lower end of the hollow cavity; further, a rotor component is arranged on the outer surface of the middle part of the rotating shaft, and a stator component is arranged between the rotor component and the inner wall of the shell; a bearing group is arranged on the outer surface of the lower end of the rotating shaft and the inner wall of the shell, and a bearing is arranged on the outer surface of the upper end of the rotating shaft and the inner wall of the bearing seat; the bearing seat is fixedly installed on the upper end of the shell; a positioning seat is arranged on the upper end of the rotating shaft, and an encoder is arranged on the outer surface of the positioning seat; a protective cover is arranged on the upper end of the positioning seat.

[0006] Furthermore, the hollow cavity at the lower end of the rotating shaft is provided with an axially symmetrical keyway structure.

[0007] Furthermore, a pressure sensor is installed on the circumference of the lower end surface of the rotating shaft.

[0008] Furthermore, the number of the pressure sensors is ≥2.

[0009] Furthermore, the retraction shaft unit includes a nut, a retraction shaft, and a stop nut. The nut is installed in a larger hollow cavity at the lower end of the rotating shaft, and an internal thread structure that is compatible with the external thread of the retraction shaft is provided on the middle inner surface of the nut; further, a stop nut with an external thread is installed at the lower end of the nut.

[0010] Furthermore, the outer surface of the nut is provided with a keyway structure adapted to the keyway of the hollow cavity of the rotating shaft.

[0011] Furthermore, a shoulder structure is provided at the lower end of the retraction shaft.

[0012] Furthermore, the outer diameter of the shaft shoulder of the retraction shaft is larger than the radial dimension of the sensor.

[0013] The beneficial effects of the present invention are: 1. The friction stir welding retraction spindle converts the rotational motion of the electric spindle unit into axial linear motion of the retraction shaft by arranging a retraction shaft unit inside. The axial reciprocating motion of the retraction shaft is realized through the control of the driver, thereby further driving the retraction of the stirring needle; 2. Pressure sensors are installed on the rotating shaft end faces of the stirring spindle and the electric spindle unit adjacent to each other at the two end faces of the shaft shoulder of the retraction shaft to control the axial displacement stroke of the retraction shaft and transmit the pressure signal in time to ensure that the normal retraction force of the friction stir welding spindle can adapt to the requirements of different welding working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the cross-section of the friction stir welding retraction spindle structure.

[0015] Figure 2 Schematic diagram of the rotating shaft structure of the electric spindle unit for friction stir welding retraction spindle.

[0016] The numbers in the figure are 100-retraction shaft, 200-rotating shaft, 300-sealing ring, 400-end cover, 500-housing, 600-stator component, 700-rotor component, 800-bearing seat, 900-locating seat, 1000-encoder, 1100-protective cover, 1200-bearing, 1300-bearing group, 1400-nut, 1500-stop nut, 1600-pressure sensor, 1700-back cover. DETAILED DESCRIPTION

[0017] The following combination Figure 1 、 2 The stir friction welding retraction spindle of the utility model is described in more detail through specific implementation methods.

[0018] In the description of the present invention, it should be noted that the terms "up", "down", "left", "right", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0019] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0020] like Figure 1-2 As shown, a friction stir welding retraction spindle of the present invention includes an electric spindle unit and a retraction shaft unit, wherein the electric spindle unit is arranged at the upper end of the friction stir welding spindle, and the retraction shaft unit is arranged and installed in the internal cavity of the electric spindle unit, and the rotational motion of the electric spindle unit is converted into the axial movement of the retraction shaft 100, which plays a role in driving the front end stirring head to insert and retract; further, a pressure sensor 1600 is arranged and installed on the opposite surfaces of the friction stir welding stirring spindle and the friction stir welding retraction spindle, and the shoulder of the retraction shaft 100 performs retraction motion between the friction stir welding stirring spindle and the friction stir welding retraction spindle.

[0021] The electric spindle unit includes a rotating shaft 200, a sealing ring 300, an end cover 400, a housing 500, a stator component 600, a rotor component 700, a bearing seat 800, a positioning seat 900, an encoder 1000, a protective cover 1100, a bearing 1200, and a bearing group 1300. The rotating shaft 200 is configured as a stepped hollow structure, a larger hollow cavity is provided at the lower end of the rotating shaft 200, and a retraction shaft unit is installed on the inner wall of the lower end of the hollow cavity; further, a rotor component 400 is installed on the outer surface of the middle part of the rotating shaft 200, and a stator component 600 is provided between the rotor component 700 and the inner wall of the housing 500; on the outer surface of the lower end of the rotating shaft 200 and the inner wall of the housing 500 A bearing group 1300 is provided, and a bearing 1200 is provided on the outer surface of the upper end of the rotating shaft 200 and the inner wall of the bearing seat 900. The rotation of the rotating shaft 200 is supported by the bearing group 1300 and the bearing 1200 at the upper and lower ends of the rotating shaft 200; further, the bearing seat 800 is fixedly installed on the upper end of the shell 500; a positioning seat 900 is provided at the upper end of the rotating shaft 200, and an encoder 1000 is provided on the outer surface of the positioning seat 900. The rotational displacement of the rotating shaft 200 is controlled by the signal transmission of the encoder 1000, and the precise welding depth and retraction stroke are implemented; a protective cover 1100 is provided at the upper end of the positioning seat 900 to play a protective role and prevent dust from entering.

[0022] Furthermore, the hollow cavity at the lower end of the rotating shaft 200 is provided with an axially symmetrical keyway structure, which is matched with the installation key block to prevent the nut 1400 of the retraction unit from rotating.

[0023] Furthermore, a pressure sensor 1600 is installed on the lower end surface of the rotating shaft 200, which can transmit a pressure signal when under pressure.

[0024] Furthermore, the number of the pressure sensors 1600 is ≥2.

[0025] The retraction shaft unit includes a nut 1400, a retraction shaft 100, and a stop nut 1500. The nut 1400 is arranged and installed in a larger hollow cavity at the lower end of the rotating shaft 200, and an internal thread structure that is compatible with the external thread of the retraction shaft 100 is provided on the middle inner surface of the nut 1400; further, a stop nut 1500 with an external thread is installed at the lower end of the nut 1400, and the axial displacement of the nut 1400 is fixed by the thread cooperation of the stop nut 1500 and the rotating shaft 200; the rotation of the rotating shaft 200 of the electric spindle unit drives the nut 1400 to rotate synchronously, and further, through the cooperation of the internal and external threads of the nut 1400 and the retraction shaft 100, the rotational motion of the rotating shaft 200 is converted into axial movement of the retraction shaft 100, thereby realizing the stirring, extension and retraction effects of the retraction shaft 100.

[0026] Furthermore, the outer surface of the nut 1400 is provided with a keyway structure adapted to the keyway of the hollow cavity of the rotating shaft 200, and a matching key block is installed to prevent the nut 1400 from rotating.

[0027] Furthermore, a shoulder structure is provided at the lower end of the retraction shaft 100 , and when the shoulder structure contacts the stress sensor 1600 , it detects the axial pressure transmitted by the retraction shaft 100 in real time; further, the outer diameter of the shoulder of the retraction shaft 100 is larger than the radial dimension of the sensor 1600 .

[0028] The usage process or working state of the utility model: the electric spindle unit is externally driven by the frequency converter. After power is turned on, the rotating shaft 200 is driven to rotate under the electromagnetic action of the stator component 400 and the rotor component 600. The rotation of the rotating shaft 200 further drives the nut 1400 set in the internal cavity to rotate synchronously. Through the cooperation between the internal and external threads of the nut 1400 and the retraction shaft 100, the retraction shaft 100 performs axial reciprocating linear motion, and the rotational motion of the rotating shaft 200 is converted into the axial movement of the retraction shaft 100, thereby realizing the stirring, extension and retraction effects of the retraction shaft 100.

[0029] Furthermore, the upper and lower end surfaces of the shoulder of the retraction shaft 100 contact the rear cover 1700 of the friction stir welding stirring spindle unit and the pressure sensor 1600 of the friction stir welding retraction spindle electric spindle unit rotating shaft 200, and transmit the pressure signal in time to ensure the normal retraction force of the friction stir welding retraction spindle.

[0030] Furthermore, the signal transmission of the encoder 1000 is used to control the rotation displacement of the rotating shaft 200 and implement precise welding depth and retraction stroke.

[0031] Each embodiment in this specification is described in a related manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

[0033] The above embodiments should not limit the present invention in any way. Any technical solutions obtained by equivalent replacement or equivalent conversion fall within the protection scope of the present invention.

Claims

1. A friction stir welding retraction spindle, comprising an electric spindle unit and a retraction spindle unit, characterized in that: The electric spindle unit is arranged at the upper end of the stirring spindle, and a retraction shaft unit is arranged and installed in the internal cavity of the electric spindle unit; Furthermore, pressure sensors are installed on the axially opposite surfaces of the stirring main shaft and the retraction main shaft.

2. The friction stir welding retraction spindle according to claim 1, characterized in that: The electric spindle includes a rotating shaft, a sealing ring, an end cover, a shell, a stator component, a rotor component, a bearing seat, a positioning seat, an encoder, a protective sleeve, a bearing, and a bearing group. The rotating shaft is arranged to have a stepped hollow structure, a larger hollow cavity is arranged at the lower end of the rotating shaft, and a retraction shaft unit is arranged on the inner wall of the lower end of the hollow cavity; further, a rotor component is arranged on the outer surface of the middle part of the rotating shaft, and a stator component is arranged between the rotor component and the inner wall of the shell; a bearing group is arranged on the outer surface of the lower end of the rotating shaft and the inner wall of the shell, and a bearing is arranged on the outer surface of the upper end of the rotating shaft and the inner wall of the bearing seat; the bearing seat is fixedly installed on the upper end of the shell; a positioning seat is arranged on the upper end of the rotating shaft, and an encoder is arranged on the outer surface of the positioning seat; a protective cover is arranged on the upper end of the positioning seat.

3. The friction stir welding retraction spindle according to claim 2, characterized in that: The hollow cavity at the lower end of the rotating shaft is provided with an axially symmetrical keyway structure.

4. A friction stir welding retraction spindle according to claim 2 or 3, characterized in that: A pressure sensor is installed on the circumference of the lower end surface of the rotating shaft.

5. A friction stir welding retraction spindle according to claim 1 or 4, characterized in that: The number of the pressure sensors is ≥2.

6. The friction stir welding retraction spindle according to claim 1, characterized in that: The retraction shaft unit includes a nut, a retraction shaft, and a stop nut. The nut is installed in a larger hollow cavity at the lower end of the rotating shaft. An internal thread structure that is compatible with the external thread of the retraction shaft is provided on the middle inner surface of the nut; a stop nut with an external thread is further provided and installed at the lower end of the nut.

7. The friction stir welding retraction spindle according to claim 6, characterized in that: The outer surface of the nut is provided with a keyway structure adapted to the keyway of the hollow cavity of the rotating shaft.

8. The friction stir welding retraction spindle according to claim 6, characterized in that: A shaft shoulder structure is provided at the lower end of the retraction shaft.

9. The friction stir welding retraction spindle according to claim 6 or 8, characterized in that: The outer diameter of the shaft shoulder of the retraction shaft is larger than the radial dimension of the sensor.

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