Mandrel fixing structure, brushless motor and fascia gun

Abstract

The utility model relates to the technical field of motor components, and provides a mandrel fixing structure which comprises a mandrel and a casing which are fixedly sleeved through a bushing. The bushing comprises a sleeve fixedly sleeved with the mandrel and a lantern ring fixedly arranged outside the sleeve and used for being fixedly sleeved with the machine shell; the mandrel and the sleeve are fixedly connected in a sleeved mode in a riveting mode. The length of the sleeve is greater than the wall thickness of the shell; and a circumferential weld is formed at the sleeving position of the casing and the lantern ring. Therefore, the casing and the mandrel are stably connected through the lining, the sleeve and the mandrel are fixedly connected in a sleeving mode in a riveting mode, the contact area of the sleeve and the mandrel is large, and the stability of connection of the sleeve and the mandrel is good. A circumferential weld is formed between the lantern ring and the casing, and the connector is small in size and high in strength. According to the utility model, the existing interference fit mode is improved, the connection strength of the shell and the mandrel is improved, and the shell and the mandrel are not easy to loosen under the working condition of large torsion. The utility model also provides a brushless motor and a fascia gun.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor components, and in particular relates to a core shaft fixing structure, a brushless motor and a fascia gun. Background Art

[0002] At present, the core shaft and the housing of the brushless motor are mostly connected by interference fit. Due to the limitation of the housing wall thickness, the contact area between the core shaft and the housing is small, and it is easy to loosen under the action of large external force or alternating stress.

[0003] For example, when using a fascia gun that is small in size and has a large torque, the matching position between the mandrel and the housing is prone to loosening, which brings inconvenience to use and maintenance.

[0004] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Utility Model Content

[0005] The utility model provides a core shaft fixing structure, aiming to solve the technical problem of low connection strength between the core shaft and the casing.

[0006] In order to achieve the above-mentioned purpose, a mandrel fixing structure of the utility model comprises a mandrel and a casing, wherein the mandrel and the casing are fixedly sleeved by a bushing;

[0007] The bushing includes a sleeve for fixedly sleeved axle, and a collar fixedly arranged outside the sleeve for fixedly sleeved axle with the housing;

[0008] The core shaft and the sleeve are fixedly connected by riveting; the length of the sleeve is greater than the wall thickness of the casing;

[0009] A ring weld is formed at the sleeve connection position between the casing and the sleeve ring.

[0010] According to the core shaft fixing structure of the utility model, the length of the sleeve is at least five times the thickness of the casing wall.

[0011] According to the core shaft fixing structure of the utility model, the length of the sleeve is 6-8 times the thickness of the casing wall.

[0012] According to the core shaft fixing structure of the utility model, an inserting strip is provided on the outer wall of the core shaft, and a slot matching with the inserting strip is correspondingly provided on the inner wall of the sleeve.

[0013] According to the core shaft fixing structure of the utility model, the annular weld is formed by laser welding.

[0014] According to the core shaft fixing structure of the utility model, a groove surface is provided on the outer circumference of the collar, and the groove surface forms an angle of 45° with the horizontal plane.

[0015] A brushless motor, comprising:

[0016] A rotor assembly, the rotor assembly comprising a housing and a core shaft of the core shaft fixing structure;

[0017] A stator assembly is sleeved outside the core shaft; the stator assembly includes a stator chip;

[0018] The magnet group is fixed on the inner wall of the housing; the magnet group includes a plurality of magnet pieces uniformly arranged on the outside of the stator chip.

[0019] According to the brushless motor of the utility model, a magnetic sheet fixing ring is fixed on the inner wall of the housing; a plurality of groove teeth are protruded on the magnetic sheet fixing ring; and a magnetic sheet is fixed between two adjacent groove teeth.

[0020] The brushless motor according to the utility model further includes:

[0021] A bearing seat plate, the center of which is rotatably sleeved on the core shaft; the bearing seat plate is also provided with a vent hole group;

[0022] A suction member, fixedly mounted on one end of the core shaft;

[0023] The suction member is configured to rotate with the core shaft to generate negative pressure, thereby generating a suction airflow flowing along the axial direction of the core shaft.

[0024] A fascia gun comprises the brushless motor.

[0025] The utility model provides a core shaft fixing structure, which realizes a stable connection between the casing and the core shaft through a bushing: the sleeve and the core shaft are fixedly sleeved by riveting, and the contact area between the two is large and the stability of the connection is good; a ring weld is formed between the sleeve ring and the casing, and the joint is small in size and high in strength. The utility model improves the existing interference fit method, improves the connection strength between the casing and the core shaft, and is not easy to loosen under high torque conditions. The utility model also provides a brushless motor and a fascia gun. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the mandrel fixing structure of the utility model;

[0027] Figure 2 It is a structural schematic diagram of another viewing direction of the mandrel fixing structure of the utility model;

[0028] Figure 3 It is a schematic diagram of the matching structure of the mandrel and the bushing of the utility model;

[0029] Figure 4 It is a schematic diagram of the matching structure of the casing and the bushing of the utility model;

[0030] Figure 5 yes Figure 4 The structural diagram of the middle A direction;

[0031] Figure 6 yes Figure 5 Schematic diagram of the structure of the middle B area;

[0032] Figure 7 It is a structural schematic diagram of the brushless motor of the utility model;

[0033] Figure 8 It is an exploded view of the brushless motor of the utility model;

[0034] Fig. 9 yes Figure 7 The main view;

[0035] Fig.10 yes Figure 7 Front view of the middle bearing seat plate;

[0036] Fig.11 It is a structural schematic diagram of the suction piece of the utility model;

[0037] In the figure: 1-bushing, 11-sleeve, 111-slot; 12-ring, 121-groove surface; 13-annular weld; 2-casing, 21-magnet group, 22-magnet plate fixing ring, 23-air hole, 24-groove tooth; 3-core shaft, 31-output end, 32-insertion strip; 4-suction piece, 41-blade; 5-bearing seat plate, 51-external air vent, 52-inner air vent, 53-mounting hole, 54-stator chip. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0039] See also Figure 1-3 The utility model provides a core shaft fixing structure, comprising a core shaft 3 and a casing 2, wherein the core shaft 3 and the casing 2 are fixedly sleeved by a bushing 1;

[0040] The bushing 1 includes a sleeve 11 fixedly sleeved with the core shaft 3, and a collar 12 fixedly arranged outside the sleeve 11 and used for fixedly sleeved with the housing 2;

[0041] As an implementation method of the sleeve 11 of the mandrel 3, the mandrel 3 and the sleeve 11 are fixedly sleeved by riveting; the connection is stable; and the length of the sleeve 11 in the axial direction is much greater than the wall thickness of the housing 2, so that the matching contact surface of the sleeve 11 of the mandrel 3 is large and not easy to loosen; further, the length of the sleeve 11 of the utility model is at least five times the wall thickness of the housing 2, and the preferred length of the utility model is 6-8 times. Ensure that the two have sufficient contact area to form a stable matching relationship.

[0042] See also Figure 5 and Figure 6 As an embodiment of the sleeve 11 fixed sleeve structure of the core shaft 3, the outer wall of the core shaft 3 is provided with an inserting strip 32, and the inner wall of the sleeve 11 is correspondingly provided with a slot 111 that matches the inserting strip 32; when the core shaft 3 is pressed into the sleeve 11 by the extrusion force to form a sleeve fit, the inserting strip 32 is inserted into the slot 111, and absorbs the deformation of the core shaft 3, fills the gap of the slot 111, and forms a stable sleeve fit. The fixing strength of the two is high and it is not easy to loosen.

[0043] See also Figure 4 As an implementation method of the fixed sleeve structure of the casing 2 and the collar 12, a ring weld 13 is formed at the sleeve position of the casing 2 and the collar 12; the fixed connection is achieved by welding, the joint has a small size, high strength, fast joint forming speed and low cost.

[0044] Furthermore, the annular weld 13 is formed by laser welding, using laser as a welding heat source, with high energy density, small heat-affected zone, high weld quality, and guaranteed connection strength.

[0045] Preferably, the outer circumference of the collar 12 is provided with a groove surface 121, which is conducive to the molten metal filling the gap during welding to form a high-quality weld. Preferably, the groove surface 121 is at an angle of 45° with the horizontal plane.

[0046] The mandrel fixing structure of the utility model realizes a stable connection between the housing 2 and the mandrel 3 through the bushing 1: the sleeve 11 and the mandrel 3 are fixedly sleeved by riveting, and the contact area between the two is large and the stability of the connection is good; a ring weld 13 is formed between the collar 12 and the housing 2, and the joint is small in size and high in strength. The utility model improves the existing interference fit method, improves the connection strength between the housing 2 and the mandrel 3, and is not easy to loosen under high torque conditions.

[0047] See also Figure 7 and Figure 8 The utility model also provides a brushless motor having the core shaft fixing structure; comprising:

[0048] A rotor assembly, the rotor assembly comprising a casing 2 and a core shaft 3 of the core shaft fixing structure;

[0049] The stator assembly is sleeved outside the core shaft 3; the stator assembly includes a stator core plate 54;

[0050] The magnet group 21 is fixed on the inner wall of the housing 2; the magnet group 21 includes a plurality of magnet pieces uniformly arranged on the outside of the stator core 54; when current is passed through the stator core 54, an induced magnetic field is generated to drive the magnet group 21 and the housing 2 to rotate.

[0051] Optionally, a magnetic sheet fixing ring 22 is fixed on the inner wall of the housing 2; a plurality of groove teeth 24 are protruded from the magnetic sheet fixing ring 22; a magnet sheet is fixed between two adjacent groove teeth 24; the magnet sheet is fixed by the groove teeth 24, thereby improving the rotation stability of the housing 2.

[0052] Furthermore, one end of the core shaft 3 is an output end 31, and the output end 31 can be connected to a device component matched with the brushless motor, and can withstand a higher torque load.

[0053] See also Figure 9-11 As an embodiment, in order to solve the problem that the brushless motor generates high heat and needs effective heat dissipation, the brushless motor of the utility model further includes:

[0054] The bearing seat plate 5 is rotatably sleeved with the core shaft 3 at its center; the bearing seat plate 5 is also provided with a vent hole group;

[0055] A suction member 4 is fixedly mounted on one end of the core shaft 3;

[0056] The suction member 4 is configured to: rotate with the core shaft 3 to generate negative pressure, thereby generating a suction airflow flowing along the axial direction of the core shaft 3;

[0057] Combination Fig. 9 The suction member 4 of the utility model rotates to throw out the air around it, thereby generating negative pressure. The airflow flows along the axial direction of the core shaft 3 from the vent group of the bearing seat plate 5 through the stator assembly and the rotor assembly to take away the generated heat.

[0058] The utility model generates suction airflow to dissipate heat by the suction member 4 rotating with the core shaft 3, which not only dissipates heat by heat conduction but also adds heat convection to improve the heat dissipation efficiency.

[0059] The rotation speed of the suction member 4 is proportional to the rotation speed of the core shaft 3. The higher the rotation speed of the core shaft 3, the greater the negative pressure generated by the suction member 4, and the flow rate of the exhaust air flow will also increase synchronously. The heat dissipation capacity can be improved with the increase of the rotation speed, which is suitable for high-speed rotation conditions and effectively guarantees the working effect.

[0060] Furthermore, a plurality of air holes 23 are provided on the end surface of the housing 2 facing the suction member 4 to increase the heat exchange channel of the suction airflow and improve the heat exchange efficiency.

[0061] Preferably, a plurality of airflow channels are formed on the stator core 54, through which the suction airflow can flow, thereby achieving effective heat dissipation;

[0062] See also Fig.10 As an embodiment of the vent group of the utility model, the vent group includes a plurality of outer vents 51 evenly arranged around the center of the bearing seat plate 5; the outer vents 51 are preferably fan-shaped, and the center of the fan-shaped vents coincides with the center of the bearing seat plate 5.

[0063] Furthermore, the vent hole group further includes a plurality of inner vent holes 52 evenly arranged around the center of the bearing seat plate 5;

[0064] After the air passes through the inner vent hole 52 and the outer vent hole 51 respectively, two air flows with different distances from the core shaft 3 are formed, thereby improving the heat dissipation efficiency.

[0065] See also Fig.11 As an embodiment of the suction member 4 of the utility model, the suction member 4 includes a rotating disk, which is fixedly connected to the core shaft 3; a plurality of blades 41 are evenly arranged on the rotating disk; as the rotating disk rotates, each blade 41 drives the airflow to be thrown out to the periphery, thereby generating negative pressure at the center position.

[0066] Furthermore, the number of blades 41 on the rotating disk is 6-8, and each of the blades 41 is inclined in the same direction, so as to increase the centrifugal force of the ejection, increase the negative pressure intensity, and improve the suction effect.

[0067] The utility model also provides a fascia gun, which has the brushless motor. The fascia gun of the utility model can withstand a large torque load and is not prone to damage.

[0068] Furthermore, the bearing seat plate 5 is provided with a plurality of mounting holes 53 to facilitate the installation and fixation of the brushless motor.

[0069] Those skilled in the art can install the brushless motor of the utility model according to the known fascia gun structure, such as the fascia gun structure and the positional relationship, connection relationship and matching relationship of the brushless motor in the fascia gun disclosed in the Chinese patent publication number CN210844180U.

[0070] In summary, the utility model provides a core shaft fixing structure, which realizes a stable connection between the casing and the core shaft through a bushing: the sleeve and the core shaft are fixedly connected by riveting, and the contact area between the two is large and the stability of the connection is good; a ring weld is formed between the sleeve and the casing, and the joint is small in size and high in strength. The utility model improves the existing interference fit method, increases the connection strength between the casing and the core shaft, and is not prone to loosening under high torque conditions. The utility model also provides a brushless motor and a fascia gun.

[0071] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field can make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A core shaft fixing structure, characterized in that: It comprises a core shaft and a casing, wherein the core shaft and the casing are fixedly sleeved by a bushing; The bushing includes a sleeve for fixedly sleeved axle, and a collar fixedly arranged outside the sleeve for fixedly sleeved axle with the housing; The core shaft and the sleeve are fixedly connected by riveting; the length of the sleeve is greater than the wall thickness of the casing; A ring weld is formed at the sleeve connection position between the casing and the sleeve ring.

2. The core shaft fixing structure according to claim 1, characterized in that: The length of the sleeve is at least five times the thickness of the casing wall.

3. The core shaft fixing structure according to claim 2, characterized in that: The length of the sleeve is 6-8 times the thickness of the casing wall.

4. The core shaft fixing structure according to claim 1, characterized in that: An inserting strip is arranged on the outer wall of the core shaft, and a slot matching with the inserting strip is correspondingly arranged on the inner wall of the sleeve.

5. The core shaft fixing structure according to claim 1, characterized in that: The annular weld is formed by laser welding.

6. The core shaft fixing structure according to claim 1, characterized in that: A groove surface is provided on the outer circumference of the collar, and the groove surface forms an angle of 45° with the horizontal plane.

7. A brushless motor, characterized in that: include: A rotor assembly, the rotor assembly comprising a housing and a core shaft of the core shaft fixing structure according to any one of claims 1 to 6; A stator assembly is sleeved outside the core shaft; the stator assembly includes a stator chip; The magnet group is fixed on the inner wall of the housing; the magnet group includes a plurality of magnet pieces uniformly arranged on the outside of the stator chip.

8. The brushless motor according to claim 7, characterized in that: A magnetic sheet fixing ring is fixed on the inner wall of the housing; a plurality of groove teeth are protruded from the magnetic sheet fixing ring; and a magnetic sheet is fixed between two adjacent groove teeth.

9. The brushless motor according to claim 7, characterized in that: Also includes: A bearing seat plate, the center of which is rotatably sleeved on the core shaft; the bearing seat plate is also provided with a vent hole group; A suction member, fixedly mounted on one end of the core shaft; The suction member is configured to rotate with the core shaft to generate negative pressure, thereby generating a suction airflow flowing along the axial direction of the core shaft.

10. A fascia gun, characterized in that: A brushless motor as claimed in claim 7.

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