Square hole drilling machine

Abstract

The invention provides a square hole drilling machine, and belongs to the technical field of electric tools and machine tools. The square hole drilling machine solves the problem that an existing square hole drilling machine is low in long-term use reliability and drilling quality. The square hole drilling machine comprises a machine shell, a cutter cylinder arranged in the machine shell in a penetrating mode and a main shaft penetrating through the cutter cylinder and rotationally connected with the machine shell, a square hole cutting tool bit is fixed to the front end of the cutter cylinder, a centering head is fixed to the front end of the main shaft, a holder is rotationally connected into the machine shell, and the holder and the main shaft are concentrically arranged. The cutter cylinder is axially positioned on the retainer and located at the eccentric position of the retainer, the spindle drives the retainer or the cutter cylinder to rotate through a transmission structure so that the cutter cylinder can revolve around the spindle, an inner gear ring is further fixed in the machine shell, the inner gear ring is arranged around the cutter cylinder and is concentric with the spindle, and the cutter cylinder is rotationally connected with the retainer. Outer teeth meshed with the inner gear ring are arranged on the outer wall of the cutter cylinder in the circumferential direction. The square hole drilling machine can improve the reliability of long-term use and ensure the drilling quality.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electric tools and machine tools, and relates to a square hole drilling machine. BACKGROUND

[0002] The square hole drilling machine is an electric tool for drilling square holes in various materials, and is widely used in the fields of furniture manufacturing, building decoration, mechanical processing, etc. The square hole drilling machine currently generally adopts the Lely triangle principle to realize the processing of square holes, i.e. driving the Lely triangle-shaped Lely tool head to couple with the revolution and rotation at a set speed, so as to process square holes.

[0003] As disclosed in the patent document (application number: 201611020828.9), the square hole drilling machine includes a shell, a guide square frame is fixed in the shell, a Lely triangular block is arranged in the guide square frame, a hollow square hole milling cutter is arranged at the lower end of the Lely triangular block, a driving rod is rotationally connected to the middle part of the shell, the driving rod passes through the Lely triangular block and the square hole milling cutter, and a centering head is fixed at the extending end of the driving rod, a small gear is arranged at the middle part of the driving rod in a concentric manner, the Lely triangular block is provided with an internal gear, the small gear is engaged with the internal gear, and when the driving rod rotates, the small gear drives the Lely triangular block to rotate and revolve through the internal gear. Since the Lely triangular block is located in the guide square frame, the revolving track is constrained by the guide square frame, so that the square hole milling cutter is coupled to rotate and revolve to open a square hole. The square hole milling cutter of the comparative document is driven to rotate and revolve through the engagement of the small gear and the internal gear, i.e. the driving force of the rotation and revolution is transmitted to the internal gear through the small gear, which causes the small gear and the internal gear to be easily worn and damaged, especially the revolution of the square hole milling cutter depends on the guidance and constraint of the Lely triangular block by the guide square frame, which causes the Lely triangular block and the guide square frame to be easily worn and damaged, thereby affecting the opening precision, and the friction between the two increases the resistance to the rotation of the square hole milling cutter and increases the energy consumption. Moreover, the square hole milling cutter needs to be pushed forward during the opening processing, the reaction force of the square hole milling cutter is pressed on the end surface of the shell through the Lely triangular block, the Lely triangular block rotates and deviates, and a large friction and wear are generated between the Lely triangular block and the shell, which affects the opening quality and increases the energy consumption. SUMMARY

[0004] The purpose of the present application is to solve the above problems of the existing technology, and to provide a square hole drilling machine which can improve the reliability of long-term use and ensure the opening quality.

[0005] The purpose of the present application can be realized by the following technical scheme: a square hole drilling machine, comprising a machine shell, a cutter barrel arranged in the machine shell, and a main shaft penetrating through the cutter barrel and rotationally connected with the machine shell, the front end of the cutter barrel extending out of the machine shell and fixed with a square hole cutting head, the front end of the main shaft extending out of the cutter barrel and fixed with a centering head, characterized in that a retainer is rotationally connected in the machine shell, the retainer being concentrically arranged with the main shaft, the cutter barrel being axially positioned on the retainer and located at an eccentric position of the retainer, the main shaft driving the retainer or the cutter barrel to rotate through a transmission structure so that the cutter barrel revolves around the main shaft, an inner ring gear is further fixed in the machine shell, the inner ring gear being arranged around the cutter barrel and concentric with the main shaft, the cutter barrel being rotationally connected with the retainer, and the outer wall of the cutter barrel being circumferentially provided with external teeth meshing with the inner ring gear.

[0006] The Lely tool bit is a tool bit designed by using the Lely triangle characteristics, and when the Lely tool bit is coupled with the revolution and rotation set, a square hole can be machined, which is also the common tool bit for machining square holes at present. The square hole cutting tool bit of the square hole drilling machine is a Lely tool bit, which uses the principle of machining square holes by using the Lely tool bit to ensure the stability and reliability of the Lely tool bit rotation and revolution. When in use, the square hole drilling machine is installed on a power tool such as an electric hammer, an electric drill or a drilling machine, a milling machine and the like. That is, the machine shell of the square hole drilling machine is connected with the shell of the power tool, the driving shaft of the power tool is connected with the main shaft, the driving shaft can drive the main shaft to rotate, and the centering head at the front end of the main shaft can be a drill bit with cutting function or a circular head with only positioning function. The former can directly machine a positioning hole on the object for positioning, and the latter needs to machine a positioning hole on the object in advance, and then the centering head is inserted into the positioning hole for positioning. Therefore, when machining, the centering head is first drilled or inserted into the object for center positioning, so as to avoid the square hole cutting tool bit from swinging due to revolution on the object, ensure the hole machining quality, and the user does not need to hold the centering head with force, but only needs to exert forward pushing force and anti-twisting force, so that the operation is more labor-saving and convenient. Since the retainer is arranged concentrically with the main shaft, and the cutter barrel is arranged at the eccentric position of the retainer, that is, the cutter barrel is eccentric relative to the main shaft, when the main shaft rotates and drives the retainer to rotate through the transmission structure, the cutter barrel on the retainer will revolve around the main shaft. An inner ring gear is fixed in the machine shell, and the inner ring gear can also be an integral structure with the machine shell. When the cutter barrel revolves, the cutter barrel rotates due to the meshing of the outer teeth on the outer wall of the cutter barrel and the inner ring gear fixed in the machine shell, and the tooth number ratio of the outer teeth of the cutter barrel to the inner ring gear is 3:4, so that the coupling of the rotation and revolution of the square hole cutting tool bit is realized, and a square hole is machined on the object. The square hole cutting tool bit needs to exert forward pushing force and circumferential torque for cutting during the hole machining process, and the present application is provided with a retainer which is rotatably connected to the machine shell and axially positioned on the retainer, so that the power tool exerts forward pushing force during the hole machining process, the shell of the power tool pushes the machine shell forward, the machine shell pushes the cutter barrel forward through the retainer, and the forward pushing of the square hole cutting tool bit is realized, that is, the retainer plays a role of transmitting the pushing force of the machine shell to the cutter barrel, and the main shaft only needs to bear the force of drilling the centering head, so that the axial load of the main shaft is greatly reduced, and the stability and reliability of the main shaft are ensured. Correspondingly, since the main shaft drives the cutter barrel to revolve through the retainer, the outer teeth of the cutter barrel only need to mesh with the inner ring gear to drive the cutter barrel to rotate, the load is relatively small, the wear between them is reduced, the machining precision is ensured, and the reliability during long-term use is ensured. Especially when the retainer drives the cutter barrel to revolve, the cutter barrel rotates by meshing the outer teeth with the inner ring gear, so that the Lely triangular block and the guide square block are not needed to cooperate for trajectory guiding, the friction resistance and wear are reduced, the energy consumption is reduced, and the reliability during long-term use is ensured.

[0007] In the square hole drilling machine, the mounting hole is provided through the holder along the axial direction of the main shaft, the mounting hole is eccentrically arranged with the main shaft, the cutter barrel and the main shaft pass through the mounting hole, and the cutter barrel is rotationally connected in the mounting hole of the holder. The mounting hole facilitates the passage of the main shaft, and the cutter barrel passes through the mounting hole, so that the cutter barrel is more stable and reliable when the holder drives the cutter barrel to revolve.

[0008] In the square hole drilling machine, the holder includes two disc-shaped disc bodies, the two disc bodies are arranged in front of and behind each other and are rotationally connected in the casing, the two disc bodies are fixed between each other in the circumferential direction and are concentrically arranged with the main shaft, the inner ring gear is located between the two disc bodies, the mounting hole is provided in each of the two disc bodies, and the rear end of the cutter barrel passes through the mounting holes of the two disc bodies and is rotationally connected with the two disc bodies. The two disc bodies rotationally drive the cutter barrel to revolve along the inner ring gear, and the outer teeth of the cutter barrel are engaged with the inner ring gear to enable the cutter barrel to rotate. The structure of the two disc bodies enables the cutter barrel to be supported at two points in the axial direction, the inner ring gear is located between the two disc bodies, so that the force of the inner ring gear on the cutter barrel is located between the supporting points of the two disc bodies, and thus the force on the cutter barrel is more symmetrical, the rigidity is better, and the structure is more stable and reliable. Meanwhile, the inner ring gear is hidden between the two disc bodies, so that dust particles and the like are less likely to enter between the inner ring gear and the outer teeth, the operation is smoother, and the reliability is higher.

[0009] In the square hole drilling machine, the two disc bodies are provided with relatively protruding connecting protrusions on opposite sides, the outer teeth on one side of the cutter barrel are engaged with the inner ring gear, and the outer teeth on the other side of the cutter barrel have an avoiding gap with the inner ring gear, the two connecting protrusions extend into the avoiding gap and are circumferentially positioned by being inserted into each other in the front-rear direction through the recessed and protruding clamping keys. This structure ingeniously utilizes the engagement between the offset rear outer teeth of the cutter barrel and the inner ring gear to form an avoiding gap between the cutter barrel and the inner ring gear, and the connecting protrusions are inserted into each other in the front-rear direction through the clamping keys, so as to ensure the reliability of the circumferential positioning and facilitate the assembly of the two disc bodies.

[0010] In the square hole drilling machine, the inner cavity of the casing is through in the front-rear direction, the casing inner wall is circumferentially provided with an annular positioning protrusion, the inner ring gear is inserted and fixed on the inner side of the positioning protrusion, and the casing is further provided with two support sleeves, which are located on the front and rear sides of the positioning protrusion and abut against the end faces of the positioning protrusion. The two disc bodies are respectively embedded in the ports of the two support sleeves, and a ring of outer balls is pressed between the disc bodies and the support sleeves, and the two disc bodies are pressed against the support sleeves in the direction of the inner ring gear through the outer balls. The positioning protrusion supports and positions the inner ring gear and the two disc bodies, and when the square hole drilling machine works, the positioning protrusion pushes the cutter barrel forward through the support sleeves and the disc bodies, so that the square hole cutting tool advances forward, and the cutter barrel revolves to rotate through the inner ring gear on the positioning protrusion to cut, that is, the positioning protrusion on the casing fixes the inner ring gear to transmit driving force, so that the whole structure is more stable and reliable.

[0011] In the square hole drilling machine, the front end outer edge of the inner gear ring is provided with an annular abutting protrusion in the circumferential direction, the front end inner edge of the positioning protrusion is provided with an annular recess shoulder in the circumferential direction, the abutting protrusion of the inner gear ring is abutted in the recess shoulder of the positioning protrusion, a slot is formed on the outer peripheral wall of the inner gear ring, a through hole is formed through the side wall of the shell, a plug is fixedly inserted into the slot and is provided with a plug pin, and gaps are formed between the two end faces of the inner gear ring and the end faces of the two disc bodies. The positioning protrusion limits the inner gear ring through the recess shoulder, and then the plug pin fixes the inner gear ring in position, and gaps are formed between the two disc bodies of the retainer and the inner gear ring, so that interference with the inner gear ring is avoided, and the stability of the rotation of the retainer is ensured.

[0012] In the square hole drilling machine, the outer wall of the cutter barrel is provided with an annular limiting protrusion in the circumferential direction, the rear end of the cutter barrel passes through the mounting holes of the two disc bodies and is screwed with a locking nut, and a ring of inner balls is pressed between the limiting protrusion and the disc body on the front side and between the locking nut and the disc body on the rear end. When the locking nut is locked, the limiting protrusion and the locking nut are respectively pressed on the two disc bodies in the direction of the inner gear ring through the inner balls. When the locking nut is locked, the limiting protrusion and the locking nut are respectively pressed on the two disc bodies in the direction of the inner gear ring, the two disc bodies are respectively pressed on the two support sleeves in the direction of the inner gear ring, the inner gear ring is inserted into the positioning protrusion and fixed during assembly, the two support sleeves are respectively inserted into the shell from the front and rear ends and abut against the end faces of the support protrusions, then the outer balls are filled in the inner walls of the two support sleeves, the two disc bodies are embedded in the support sleeves from the front and rear ends, the inner balls are filled in the inner sides of the disc bodies, and finally the rear end of the cutter barrel passes through the two disc bodies from front to rear and is locked by the locking nut. At this time, the limiting protrusion on the cutter barrel is pressed on the disc body on the front side through the inner ball on the front side, the locking nut is pressed on the disc body on the rear end through the inner ball on the rear end, and the two disc bodies are respectively pressed on the two support sleeves through the respective outer balls, so that the two support sleeves are pressed on the positioning protrusion. This structure is easy to assemble, and has high stability and reliability after assembly.

[0013] In the square hole drilling machine, the transmission structure includes a torsion arm fixed to the rear end of the main shaft and extending radially, and the torsion arm is fixed to the eccentric position of the disc body on the rear end through a positioning pin. The main shaft drives the disc body on the rear end through the torsion arm, the disc body on the rear end drives the disc body on the front end to rotate synchronously through the connecting protrusion, the transmission of driving force is realized, energy loss is reduced, and the structural reliability is improved.

[0014] In the aforementioned square hole drilling rig, a rear dust cover is fixedly fitted onto the rear end of the spindle. This dust cover is embedded in the rear support sleeve and covers the rear end face of the rear disc. The aforementioned locking nut is located inside the dust cover, and the torque arm is integrally formed onto the rear end face of the rear dust cover. The rear dust cover seals the moving parts inside the housing from the rear end, ensuring smooth and reliable internal transmission. Simultaneously, integrally forming the torque arm onto the rear end face of the dust cover makes the structure more compact and improves the structural strength of the torque arm, ensuring long-term reliability.

[0015] In the aforementioned square hole drilling rig, the transmission structure includes a transmission gear fixed to the rear end of the spindle, and a transmission gear sleeve fixed to the rear end of the cutter barrel. The transmission gear is located inside the transmission gear sleeve and meshes with it. When the transmission gear rotates, it drives the transmission gear sleeve to revolve around the transmission gear, thereby driving the cutter barrel to rotate and revolve, and the cutter barrel pushes the retainer to rotate.

[0016] Compared with existing technologies, this square hole drilling rig has the following advantages:

[0017] 1. During hole drilling, the power tool applies a forward thrust, and the power tool housing pushes the square hole drill housing forward. The housing pushes the tool barrel forward through the cage, thus advancing the square hole cutting head. In other words, the cage transfers the thrust of the housing to the tool barrel, while the spindle only needs to bear the force of the centering head drilling, which greatly reduces the axial load on the spindle and ensures the stability and reliability of the spindle.

[0018] 2. Since the spindle drives the cage to rotate the tool barrel, the external gear of the tool barrel only needs to mesh with the internal gear ring to drive the tool barrel to rotate. The load is relatively small, reducing mutual wear and ensuring machining accuracy and long-term reliability.

[0019] 3. Since the cage drives the tool barrel to revolve and the internal gear ring drives the tool barrel to rotate, there is no need for the Reilly triangle block and guide block to cooperate for trajectory guidance, which reduces frictional resistance and wear, thereby reducing energy consumption and ensuring long-term reliability.

[0020] 4. Because the cage includes two discs, the cutter barrel is supported at two points in the axial direction. The internal gear ring is located between the two discs, so the force exerted by the internal gear ring on the cutter barrel is located between the support points of the two discs. Therefore, the force on the cutter barrel is more symmetrical, and the structure is more stable and reliable.

[0021] 5. Since the torque arm is integrally molded on the rear end face of the rear dust cover, the structure is more compact, and the structural strength of the torque arm is improved by the rear dust cover, ensuring the reliability of long-term use. Attached Figure Description

[0022] Figure 1This is a three-dimensional structural diagram of a square hole drilling rig.

[0023] Figure 2 This is a front view of the structure of a square hole drilling rig.

[0024] Figure 3 yes Figure 2 Longitudinal structural cross-sectional view at point AA.

[0025] Figure 4 This is a cross-sectional view of the transverse structure at the internal gear ring of a square hole drilling rig.

[0026] Figure 5 yes Figure 2 A longitudinal partial structural cross-sectional view at point BB.

[0027] Figure 6 It is an exploded view of the structure of components such as the cage.

[0028] Figure 7 This is a schematic diagram of the three-dimensional structure of the cage.

[0029] Figure 8 This is a three-dimensional structural diagram of the rear dust cover.

[0030] Figure 9 This is a structural cross-sectional view of the square hole drilling machine in Embodiment 2.

[0031] In the diagram, 1. Housing; 11. Positioning flange; 111. Shoulder; 112. Annular groove; 12. Through hole; 2. Tool barrel; 21. Square hole cutting head; 22. External gear; 23. Limiting flange; 3. Spindle; 31. Centering head; 4. Cage; 41. Disc; 411. Mounting hole; 412. Connecting protrusion; 413. Groove II; 414. Positioning hole; 42. Internal ball bearing; 5. Internal gear ring; 51. Abutment flange; 52. Slot; 53. Pin; 54. Clearance clearance; 6. Support sleeve; 61. Groove I; 62. External ball bearing; 7. Transmission structure; 71. Torque arm; 711. Pin hole; 712. Positioning pin; 72. Rear dust cover; 73. Transmission gear; 74. Transmission gear sleeve; 8. Locking nut sleeve; 9. Front dust cover; 10. Bearing. Detailed Implementation

[0032] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0033] Example 1:

[0034] like Figure 1 , Figure 3As shown, a square hole drilling rig includes a housing 1, a spindle 3, and a cutter barrel 2. The housing 1 has a through-cavity with a circular cross-section. The cutter barrel 2 is inserted into the housing 1, with its front end extending out of the housing 1 and fixed with a square hole cutting head 21. The spindle 3 is inserted into the cutter barrel 2, with its front end passing through the square hole cutting head 21, extending out of the cutter barrel 2, and fixed with a centering head 31. Figure 2 As shown, the square hole cutting head 21 includes a cutter head with an outer contour in the shape of a Reichstag triangle. The cutter head has three rounded edges and three sharp corners. At least three circumferentially distributed cutting blades are fixed on the front face of the cutter head, and the ends of the three cutting blades extend to the three sharp corners respectively. Figure 3 As shown, a support sleeve 6 is fixed inside the housing 1 or integrally formed with the housing 1. A retainer 4 is rotatably connected inside the support sleeve 6. A mounting hole 411 is provided through the retainer 4 in the front-rear direction. The rear end of the tool barrel 2 passes through the mounting hole 411 and is rotatably connected to the retainer 4. The rear end of the spindle 3 passes through the tool barrel 2 and is rotatably connected to the housing 1 through a bearing 10. The rear end of the spindle 3 also drives the retainer 4 to rotate through a transmission structure 7. The support sleeve 6, retainer 4, and spindle 3 are concentrically arranged. The mounting hole 411 is located at an eccentric position on the retainer 4. Therefore, the mounting hole 411 is eccentrically arranged with the spindle 3, that is, the tool barrel 2 and the spindle 3 are eccentrically arranged. Figure 4 As shown, an internal gear ring 5 is also fixed inside the housing 1. The internal gear ring 5 and the housing 1 can be a separate structure or an integrated structure. The internal gear ring 5 is arranged around the cutter barrel 2 and is concentric with the main shaft 3. The outer wall of the cutter barrel 2 has external teeth 22 in the circumferential direction. The cutter barrel 2 is eccentric to the internal gear ring 5 and the external teeth 22 on one side mesh with one side of the internal gear ring 5. There is a clearance 54 between the external teeth 22 on the other side of the cutter barrel 2 and the internal gear ring 5. The ratio of the number of teeth of the external teeth 22 of the cutter barrel 2 to the number of teeth of the internal gear ring 5 is 3:4.

[0035] Specifically, combined Figure 4 , Figure 5 As shown, the inner wall of the housing 1 has a circumferentially annular positioning protrusion 11. The inner edge of the front end of the positioning protrusion 11 has a circumferentially annular concave shoulder 111. The outer edge of the front end of the internal gear ring 5 has a circumferentially annular abutting protrusion 51. The internal gear ring 5 is inserted into the inner side of the positioning protrusion 11 with the rearward facing, and the abutting protrusion 51 of the internal gear ring 5 abuts against the concave shoulder 111 of the positioning protrusion 11. A slot 52 is provided on the outer peripheral wall of the internal gear ring 5. A through hole 12 is provided through the side wall of the housing 1. A pin 53, which is fixedly inserted into the slot 52, is fixedly inserted into the through hole 12. Both end faces of the positioning protrusion 11 have circumferentially annular grooves 112. There are two support sleeves 6. The two support sleeves 6 are located on the front and rear sides of the positioning protrusion 11 and abut against the annular grooves 112 of the positioning protrusion 11. The inner wall of the support sleeve 6 has a circumferentially annular groove 61. A ring of outer balls 62 is filled in the groove 61. Figure 5 , Figure 6, Figure 7 As shown, the cage 4 includes two disc-shaped discs 41. The two discs 41 are respectively inserted into the ports of the two support sleeves 6 from both ends, so that the internal gear ring 5 is located between the two discs 41. The discs 41 press against the outer ball 62 in the direction of the internal gear ring 5. There is a gap between the end faces of the two ends of the internal gear ring 5 and the end faces of the two discs 41. Mounting holes 411 are provided on both discs 41. The mounting holes 411 of the discs 41 have annular grooves 413 on the circumferential direction. A ring of inner balls 42 is filled in the grooves 413. The outer wall of the cutter cylinder 2 has annular limiting flanges 23 on the circumferential direction. The rear end of the cutter cylinder 2 passes through the mounting holes 411 of the two discs 41 and is screwed with a locking sleeve 8. When the locking sleeve 8 is locked, the limiting flanges 23 and the locking sleeve 8 press against the inner balls 42 in the direction of the inner gear ring 5. That is, the limiting flanges 23 and the locking sleeve 8 are pressed against the two discs 41 in the direction of the inner gear ring 5 through the inner balls 42. The two discs 41 are pressed against the two support sleeves 6 in the direction of the inner gear ring 5 through the outer balls 62. The two support sleeves 6 are pressed against the positioning flanges 11.

[0036] Two discs 41 are spaced apart and concentrically positioned with the spindle 3. The mounting hole 411 is located at an eccentric position on the disc 41. Each of the two discs 41 has a relatively protruding connecting protrusion 412 on its opposite side. The connecting protrusion 412 is strip-shaped along the circumference of the disc 41. The inner side of the connecting protrusion 412 is an arc surface and is coplanar with the wall of the mounting hole 411. Each of the connecting protrusions 412 has a concave keyway and a protruding key block on its end face. The two connecting protrusions 412 extend into the clearance 54 between the internal gear ring 5 and the tool barrel 2. The keyways and key blocks of the two connecting protrusions 412 are interlocked for circumferential positioning. A connecting pin can also be inserted between the two connecting protrusions 412 for circumferential positioning. A front dust cover 9 is fixed to the front surface of the front disc 41. This front dust cover 9 covers the outer end of the front support sleeve 6. A rear dust cover 72 is fixedly fitted to the rear end of the spindle 3. This rear dust cover 72 is embedded in the rear support sleeve 6 and covers the rear end surface of the rear disc 41. A locking screw 8 is located inside the dust cover. Figure 3 , Figure 8 As shown, the transmission structure 7 includes a torque arm 71 integrally formed on the rear end face of the dust cover. The torque arm 71 is block-shaped, and its inner end is fixed on the main shaft 3 together with the rear dust cover 72. The outer end is provided with a pin hole 711 along the axial direction of the main shaft 3. The pin hole 711 passes through the rear dust cover 72, and a positioning pin 712 passes through the pin hole 711. A positioning hole 414 is provided at the eccentric position of the rear disc 41. The positioning pin 712 is inserted and positioned in the positioning hole 414. The outer end of the torque arm 71 and the rear disc 41 are also locked and fixed by screws.

[0037] During hole drilling, the housing 1 is mounted on the electric motor. The drive shaft of the electric motor is connected to the spindle 3, which can drive the spindle 3 to rotate. The centering head 31 at the front end of the spindle 3 first drills into the object for center positioning. The spindle 3 also drives the cage 4 to rotate through the torque arm 71. The cage 4 pushes the tool barrel 2 to revolve relative to the spindle 3. At the same time, the tool barrel 2 rotates under the transmission of the external gear 22 and the internal gear ring 5, realizing the coupling of the rotation and revolution of the square hole cutting head 21 to process the square hole.

[0038] Example 2:

[0039] The structure of this square hole drilling rig is basically the same as that of Embodiment 1, the difference being that... Figure 9 As shown, the transmission structure 7 includes a transmission gear 73 fixed to the rear end of the main shaft 3, and a transmission sleeve 74 fixed to the rear end of the tool barrel 2. The transmission gear 73 is located at an eccentric position inside the transmission sleeve 74 and meshes with the transmission sleeve 74.

[0040] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0041] Although this document frequently uses terms such as housing 1, positioning flange 11, and concave shoulder 111, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A square hole drilling machine, comprising a housing (1), a cutter barrel (2) passing through the housing (1), and a spindle (3) passing through the cutter barrel (2) and rotatably connected to the housing (1), wherein the front end of the cutter barrel (2) extends out of the housing (1) and is fixed with a square hole cutting head (21), and the front end of the spindle (3) extends out of the cutter barrel (2) and is fixed with a centering head (31), characterized in that, A retainer (4) is rotatably connected inside the housing (1). The retainer (4) is concentrically arranged with the main shaft (3). The cutter barrel (2) is axially positioned on the retainer (4) and located at an eccentric position of the retainer (4). The main shaft (3) drives the retainer (4) or the cutter barrel (2) to rotate through the transmission structure (7), causing the cutter barrel (2) to revolve around the main shaft (3). An internal gear ring (5) is also fixed inside the housing (1). The internal gear ring (5) is arranged around the cutter barrel (2) and is concentric with the main shaft (3). The cutter barrel (2) is rotatably connected with the retainer (4), and the outer wall of the cutter barrel (2) has external teeth (22) that mesh with the internal gear ring (5) in the circumferential direction.

2. The square hole drilling machine according to claim 1, characterized in that, The retainer (4) has a mounting hole (411) extending through the main shaft (3) axially. The mounting hole (411) is eccentrically set with respect to the main shaft (3). The tool barrel (2) and the main shaft (3) both pass through the mounting hole (411), and the tool barrel (2) is rotatably connected in the mounting hole (411) of the retainer (4).

3. The square hole drilling machine according to claim 2, characterized in that, The retainer (4) includes two disc-shaped discs (41), which are spaced apart and rotatably connected in the housing (1). The two discs (41) are fixed circumferentially and concentrically connected with the main shaft (3). The internal gear ring (5) is located between the two discs (41). The mounting holes (411) are provided on both discs (41). The rear end of the cutter barrel (2) passes through the mounting holes (411) of the two discs (41) and is rotatably connected to the two discs (41).

4. The square hole drilling machine according to claim 3, characterized in that, Both of the disc bodies (41) have relatively protruding connecting protrusions (412) on their opposite sides. The outer teeth (22) on one side of the blade cylinder (2) mesh with the inner gear ring (5), and there is a clearance gap (54) between the outer teeth (22) on the other side and the inner gear ring (5). The two connecting protrusions (412) extend into the clearance gap (54) and are circumferentially positioned by interlocking with each other in the front-back direction through the interlocking key with concave and convex arrangement.

5. The square hole drilling machine according to claim 3 or 4, characterized in that, The inner cavity of the housing (1) extends through the front and back. A circumferentially circumferential positioning protrusion (11) is provided on the inner wall of the housing (1). The aforementioned internal gear ring (5) is inserted and fixed inside the positioning protrusion (11). Two support sleeves (6) are also provided inside the housing (1). The two support sleeves (6) are located at the front and rear ends of the positioning protrusion (11) and abut against the end face of the positioning protrusion (11). Two discs (41) are respectively embedded in the ports of the two support sleeves (6). A ring of outer ball bearings (62) is pressed between the disc (41) and the support sleeve (6). Both discs (41) are pressed against the support sleeves (6) in the direction of the internal gear ring (5) by the outer ball bearings (62).

6. The square hole drilling machine according to claim 5, characterized in that, The front outer edge of the internal gear ring (5) has an annular abutment protrusion (51) in the circumferential direction, and the front inner edge of the positioning protrusion (11) has an annular concave shoulder (111) in the circumferential direction. The abutment protrusion (51) of the internal gear ring (5) abuts against the concave shoulder (111) of the positioning protrusion (11). A slot (52) is provided on the outer peripheral wall of the internal gear ring (5), and a through hole (12) is provided on the side wall of the housing (1). A pin (53) positioned in the slot (52) is fixedly inserted into the through hole (12). There is a gap between the two end faces of the internal gear ring (5) and the end faces of the two discs (41).

7. The square hole drilling machine according to claim 6, characterized in that, The outer wall of the cutter barrel (2) has an annular limiting flange (23) in the circumferential direction. The rear end of the cutter barrel (2) passes through the mounting hole (411) of the two discs (41) and is screwed with a locking sleeve (8). A ring of inner balls (42) is pressed between the limiting flange (23) and the front disc (41) and between the locking sleeve (8) and the rear disc (41). When the locking sleeve (8) is locked, the limiting flange (23) and the locking sleeve (8) are pressed against the two discs (41) in the direction of the inner tooth ring (5) through the inner balls (42).

8. The square hole drilling machine according to claim 7, characterized in that, The transmission structure (7) includes a torque arm (71) fixed to the rear end of the main shaft (3) and extending radially. The torque arm (71) is fixed to the eccentric position of the rear disc (41) by a positioning pin (712).

9. The square hole drilling machine according to claim 8, characterized in that, The rear end of the main shaft (3) is also fixedly fitted with a rear dust cover (72), which is embedded in the rear support sleeve (6) and covers the rear end face of the rear disc (41). The locking screw sleeve (8) is located inside the rear dust cover (72), and the torque arm (71) is integrally formed on the rear end face of the rear dust cover (72).

10. The square hole drilling rig according to any one of claims 1 to 4, characterized in that, The transmission structure (7) includes a transmission gear (73) fixed at the rear end of the main shaft (3), and a transmission sleeve (74) fixed at the rear end of the cutter barrel (2). The transmission gear (73) is located at an eccentric position inside the transmission sleeve (74) and meshes with the transmission sleeve (74).

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