Adjustable boring cutter for stepped hole machining

Abstract

The invention relates to the technical field of boring tools, in particular to an adjustable boring tool for stepped hole machining, which comprises a tool body, a tool apron is arranged at the lower end of the tool body, a tool bit is fixedly connected to the lower end of the tool apron, and the tool body is formed by combining an upper tool bar, a second tool bar and a tool bar sleeve; the tool has the beneficial effects that the tool is integrated with radial and axial adjusting mechanisms, so that the tool can be precisely adjusted in the radial direction and the axial direction in the machining process according to the diameters and the hole depths of different stepped holes, the upper portion of the tool bit is protected in cooperation with an introduced variable-diameter supporting mechanism, the tool apron and the tool bit are assembled and fastened, and the machining efficiency is improved. And effective support for stepped holes with different sizes is dynamically adjusted according to machining requirements, meanwhile, the rigidity of the tool is enhanced, the cutter relieving or vibrating phenomenon of a boring cutter is avoided, the grain cutting phenomenon of the boring inner wall is avoided, the flexibility of the cutter is improved, and the machining precision and stability are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of boring tools, in particular to an adjustable boring tool for step hole processing. Background Art

[0002] Stepped hole is a common hole type in mechanical processing, with multiple hole segments of different diameters. Traditional fixed boring tools need to be replaced frequently when processing stepped holes, which not only reduces processing efficiency but also increases processing costs. With the development of the manufacturing industry, the requirements for processing efficiency and processing accuracy are constantly improving. Adjustable boring tools have come into being. They can adapt to the processing requirements of different hole diameters and hole depths by adjusting the structure or parameters of the tool.

[0003] In the prior art, there is a three-layer stepped large-diameter boring cutter for processing the front shell of a transmission case, such as the publication number CN210817498U. The tool can simultaneously process three stepped inner holes of different diameters. At the same time, each layer of the tool body adopts a sleeve-type hollow tool body, which is light in weight and simple in structure. Moreover, each layer of the tool body adopts a boring cutter slide and a boring cutter seat of the same size. The modules are of unified standards and have modularity and adjustability. Moreover, the processing depth of each hole can also be adjusted, thereby achieving the purpose of processing three large-diameter inner holes with one tool.

[0004] In actual use, it is necessary to manually adjust multiple sets of diameter adjustment bolts in sequence to adjust the axial spacing of each layer of the cutter body, and then fix the fixed connecting bolts and washers. Although this method can realize the internal hole processing of multiple layers of steps, the operation steps are cumbersome and adjustment errors are prone to occur, resulting in boring failures. In addition, when the feed and speed of traditional tools do not match, rigid vibration and tool wear occur, the cutting resistance is large, and tool vibration and tool letting-down are prone to occur. In addition, fish scale or threaded cuts appear on the processed surface, affecting dimensional stability and processing quality.

[0005] Therefore, the present invention proposes an adjustable boring tool for step hole processing to solve the problem of cumbersome adjustment steps of existing tools when processing step holes. The axial and radial directions of the boring tool can be adjusted to maintain a relatively stable boring hole diameter during the processing process, and it can adapt to the processing requirements of different hole depths, reducing the processing steps and ensuring the coaxiality requirements of the processed step holes. Summary of the invention

[0006] The object of the present invention is to provide an adjustable boring tool for step hole machining to solve the problems raised in the above background technology.

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an adjustable boring tool for step hole processing, comprising a tool body, a tool seat is arranged at the lower end of the tool body, a tool head is fixedly connected to the lower end of the tool seat, the tool body is composed of an upper tool rod, a second tool rod and a tool rod sleeve, the lower end outer surfaces of the second tool rod and the tool rod sleeve are welded and fixed to the tool seat, the inner surface of the tool head is respectively provided with a movable groove 1 and a movable groove 2, a square notch is arranged through the center of the movable groove 1 and the movable groove 2, an axial adjustment mechanism is arranged on the inner side of the square notch, a variable diameter support mechanism is arranged on the upper side of the tool head, and the variable diameter support mechanism includes a tool head sleeve and an expansion component.

[0008] Preferably, a cavity is formed on the inner surface of the upper knife rod, and a radial adjustment mechanism is provided in the inner cavity of the cavity, and the radial adjustment mechanism includes a telescopic push rod, and the telescopic push rod is fixedly installed on the inner top surface of the cavity, and the output end of the telescopic push rod is fixedly connected to the outer surface of the upper end of the knife rod 2, and the outer surface of the knife rod 2 is fixedly connected to the inner surface of the knife rod sleeve, and the outer surface of the knife rod sleeve is slidably connected to the inner wall of the cavity.

[0009] Preferably, the axial adjustment mechanism includes a screwing handle, a movable cylinder 1 and a movable cylinder 2, a gear rod is fixedly installed on the central outer surface of the screwing handle, two ends of the screwing handle are respectively rotatably connected to the inner wall of the cutter head, the movable cylinder 1 is slidably installed on the inner side of the movable groove 1, the movable cylinder 2 is slidably installed on the inner side of the movable groove 2, the lower surface of the movable cylinder 1 and the upper surface of the movable cylinder 2 are respectively provided with gear grooves that mesh with the outer surface of the gear rod, one end of the movable cylinder 2 is provided with a fixed block fixedly connected to the inner wall of the movable groove 2, the inner side surface of the fixed block is fixedly connected to a limiting rod, and the outer surface of the limiting rod is movably connected to the inner wall of the movable cylinder 2.

[0010] Preferably, a connecting rod is fixedly installed at one end of the limiting rod away from the fixed block, the outer surface of the connecting rod is fixedly connected to the inner wall of the movable cylinder 2, the outer side of the connecting rod is fixedly connected to a tool mounting seat by bolts, and the lower end of the tool mounting seat is detachably mounted with a tool.

[0011] Preferably, fastening bolts are respectively provided on the inner walls on both sides of the cutter head sleeve, the cutter head sleeve is fixedly connected to the outer surface of the cutter head by the fastening bolts, and an inner convex plate is fixedly provided on the inner ring side wall of the cutter head sleeve.

[0012] Preferably, an inner wall of the tool bit holder is provided with a receiving bevel groove, the receiving bevel groove is provided with an inclined surface at an angle of 75°, an escape groove is provided through the upper cavity of the receiving bevel groove, and the receiving bevel groove and the escape groove are provided with six groups respectively and are distributed in a circular array about the central axis of the tool bit holder.

[0013] Preferably, the extension component includes a protective convex ring and a screwing disk, the protective convex ring is fixedly mounted on the upper surface of the cutter head sleeve, the screwing disk is rotatably mounted on the upper side of the protective convex ring, the central inner surface of the screwing disk is fixedly connected to a connecting shaft, the lower end outer surface of the connecting shaft is fixedly connected to a gear, the outer surface of the gear is meshed and rotatably engaged with a gear ring, the inner ring surface of the gear ring is fixedly connected to a rotating disk, and the cross-section of the rotating disk presents a "convex" plate-like structure.

[0014] Preferably, the upper outer surface of the rotating disk is fixedly connected to a limiting ring, and a rotating groove is provided on the side wall of the upper inner ring of the tool head sleeve, and the inner surface of the rotating groove is rotatably connected to the outer surface of the limiting ring.

[0015] Preferably, arc grooves are evenly opened on the inner wall of the rotating disk, and a limiting column is movably installed on the inner surface of the arc groove. The lower end of the limiting column is fixedly connected to an extended support block, and the outer surface of the extended support block is movably connected to the inner wall of the receiving inclined groove and the avoidance groove.

[0016] Preferably, a buffer groove is opened on the outer inner wall of the limiting column, and carbon steel and alloy steel blocks are fixedly installed on the inner wall of the buffer groove. The outer surfaces of the carbon steel and alloy steel blocks are fixedly connected to support plates, and the outer surface of the support plate is movably connected to the inner wall of the buffer groove.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes an adjustable boring tool for step hole processing. The tool integrates radial and axial adjustment mechanisms, so that the tool can be accurately adjusted radially and axially according to the diameter and hole depth of different step hole sizes during the processing process. In conjunction with the introduced variable diameter support mechanism, the upper part of the tool head is protected and the assembly and tightening between the tool holder and the tool head are met. It can also dynamically adjust the effective support for step holes of different sizes according to processing requirements, enhance the rigidity of the tooling, avoid the boring tool from letting go or vibrating, and avoid the appearance of cut lines on the inner wall of the boring tool. Not only does it improve the flexibility of the tool, but it also ensures the processing accuracy and stability. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of a half-section structure of the present invention; Figure 3 It is a schematic diagram of the three-dimensional disassembled structure of the present invention; Figure 4 For the present invention Figure 3 A schematic diagram of the enlarged structure at point A; Figure 5 It is a schematic diagram of a partial cross-section structure of the axial adjustment mechanism of the present invention; Figure 6It is a schematic diagram of a partial cross-section structure of a tool head sleeve of the present invention; Figure 7 For the present invention Figure 6 A schematic diagram of the enlarged structure at B; Figure 8 It is a partial structural schematic diagram of the variable diameter support mechanism of the present invention; Fig. 9 It is a schematic diagram of a half-section structure of a gear ring of the present invention; Fig.10 It is a schematic diagram of the partial cross-sectional structure of the extension assembly of the present invention; Fig.11 It is a structural schematic diagram of the boring tool step hole processing state of the present invention.

[0018] In the figure: 1, knife body; 11, upper knife bar; 10, cavity; 12, knife bar 2; 121, knife bar sleeve; 13, telescopic push rod; 2, knife seat; 3, knife head; 30, movable groove 1; 300, movable groove 2; 301, square notch; 31, fastening bolt; 32, screw handle; 321, gear rod; 33, movable cylinder 1; 34, movable cylinder 2; 35, knife mounting seat; 351, knife; 352, connecting rod; 353, limit Position rod; 354, fixing block; 4, cutter head seat; 41, inner convex plate; 40, receiving inclined groove; 401, avoidance groove; 400, rotating groove; 42, protective convex ring; 421, screw disk; 422, gear; 423, gear ring; 4231, limiting ring; 43, rotating disk; 430, arc groove; 44, limiting column; 441, extended support block; 4410, buffer groove; 442, support plate; 443, carbon steel and alloy steel blocks. DETAILED DESCRIPTION

[0019] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present invention, rather than all of the embodiments, and are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] For example, see Figure 1 - Fig.11The present invention provides a technical solution: an adjustable boring tool for step hole processing, comprising a tool body 1, a tool seat 2 is arranged at the lower end of the tool body 1, a tool head 3 is fixedly connected to the lower end of the tool seat 2, the tool body 1 is composed of an upper tool rod 11, a tool rod 12 and a tool rod sleeve 121, the lower end outer surfaces of the tool rod 12 and the tool rod sleeve 121 are welded and fixed to the tool seat 2, the inner surface of the tool head 3 is respectively provided with a movable groove 1 30 and a movable groove 2 300, the center of the movable groove 1 30 and the movable groove 2 300 is provided with a square notch 301, and the inner side of the square notch 301 is provided with There is an axial adjustment mechanism, and a variable diameter support mechanism is arranged on the upper side of the cutter head 3, and the variable diameter support mechanism includes a cutter head sleeve seat 4 and an expansion component; a cavity 10 is opened on the inner surface of the upper cutter rod 11, and a radial adjustment mechanism is arranged in the inner cavity of the cavity 10, and the radial adjustment mechanism includes a telescopic push rod 13, and the telescopic push rod 13 is fixedly installed on the inner cavity top surface of the cavity 10, and the output end of the telescopic push rod 13 is fixedly connected to the outer surface of the upper end of the cutter rod 12, and the outer surface of the cutter rod 12 is fixedly connected to the inner surface of the cutter rod sleeve 121, and the outer surface of the cutter rod sleeve 121 is slidably connected to the inner wall of the cavity 10; In this embodiment, the tool body 1 is divided into a two-section combination. The cavity 10 opened on the inner wall of the upper tool rod 11 is used to control and install the tool rod 12 and the tool rod sleeve 121. The telescopic push rod 13 is controlled to push the top of the tool rod 12. According to the hole depth required to be processed by the boring tool, the telescopic push rod 13 accurately adjusts the lowering stroke of the tool rod 12. The inner wall of the upper tool rod 11 and the outer wall of the tool rod sleeve 121 are adapted to fit together to ensure the stability of the forward stroke section of the cutter head 3. It should be mentioned that when the tool rod sleeve 121 is in the initial state, the tool rod sleeve 121 is merged with the bottom end of the upper tool rod 11 to form a double-layer rod structure, which enhances the rigidity of the tool body 1. When the cutter head 3 is extended, the upper tool rod 11 can not only protect the tool rod 12, but also meet the stable limit of the longitudinal movement of the tool rod 12.

[0021] Embodiment 2: On the basis of embodiment 1, in order to realize that the cutter head 3 can adapt to different boring diameters and meet the axial adjustment of the tool 351, this embodiment further proposes: the axial adjustment mechanism includes a screw handle 32, a movable cylinder 1 33 and a movable cylinder 2 34, a gear rod 321 is fixedly installed on the central outer surface of the screw handle 32, and the two ends of the screw handle 32 are respectively rotatably connected to the inner wall of the cutter head 3, the movable cylinder 1 33 is slidably installed on the inner side of the movable groove 1 30, and the movable cylinder 2 34 is slidably installed on the inner side of the movable groove 2 300, and the lower surface of the movable cylinder 1 33 and the upper surface of the movable cylinder 2 34 are respectively provided with The outer surface of the gear rod 321 meshes with the matching tooth groove. One end of the movable cylinder 34 is provided with a fixed block 354 fixedly connected to the inner wall of the movable groove 300. The inner side surface of the fixed block 354 is fixedly connected to the limiting rod 353. The outer surface of the limiting rod 353 is movably connected to the inner wall of the movable cylinder 34. The end of the limiting rod 353 away from the fixed block 354 is fixedly installed with a connecting rod 352. The outer surface of the connecting rod 352 is fixedly connected to the inner wall of the movable cylinder 34. The outer side of the connecting rod 352 is fixedly connected to the tool mounting seat 35 by bolts. The lower end of the tool mounting seat 35 is detachably installed with a tool 351. When the tooth bar 321 is rotated, the toothed rod 321 rotates synchronously, and meshes with the tooth grooves on the inner sides of the movable cylinder 1 33 and the movable cylinder 2 34. When the toothed rod 321 rotates counterclockwise, the movable cylinder 1 33 and the movable cylinder 2 34 move relative to each other on both sides. During the relative movement, the movable cylinder 2 34 slides on the surface of the limit rod 353, and drives the tool mounting seat 35 and the tool 351 on one side to move. In this way, by accurately adjusting the rotation angle of the screwing handle 32, the extended distance of the tool 351 is achieved to adapt to the boring of the hole that does not pass through the diameter step hole; when the toothed rod 321 is rotated, the movable cylinder 1 33 and the movable cylinder 2 34 on both sides move inward relative to each other, so that the tool 351 is stored. Through the cooperation between this series of structures, the accuracy of the boring processing is enhanced, the operation is simple and convenient, and there is no need to repeat multiple steps of tightening the bolts, thereby reducing the operation time and processing procedures.

[0022] Embodiment 3, on the basis of embodiment 2, in order to realize the axial movement of the tool 351 and the stability of boring processing, this embodiment further proposes: a circular receiving groove is opened on the inner surface of the moving cylinder 33, and a counterweight block is arranged on the inner surface of the circular receiving groove; fastening bolts 31 are arranged on the inner walls of both sides of the cutter head sleeve 4, and the cutter head sleeve 4 is fixedly connected to the outer surface of the cutter head 3 by the fastening bolts 31, and an inner convex plate 41 is fixedly added on the inner ring side wall of the cutter head sleeve 4; In this embodiment, by arranging a counterweight block in the circular receiving groove opened on the inner surface of the moving cylinder 1 33, the dynamic imbalance of the axial adjustment mechanism during operation can be effectively balanced, especially when the moving cylinder 1 33 and the moving cylinder 2 34 perform relative movement according to the rotation of the gear rod 321, the existence of the counterweight block can reduce the vibration caused by the movement, so that the axial movement of the tool 351 is more stable, and the precision and stability of the boring process are improved. The counterweight block helps to maintain the self-balance of the entire processing system by reducing the vibration of the moving parts, thereby ensuring that the tool 351 can move accurately according to the predetermined trajectory during the processing, reducing the processing error caused by vibration, and at the same time can extend the service life of the axial adjustment mechanism and its related components, reducing the maintenance cost and replacement frequency; In addition, a cutter head sleeve 4 is installed at the connection between the cutter seat 2 and the cutter head 3, and is fastened with a fastening bolt 31. This design can not only provide structural support for the variable diameter support mechanism, but also meet the protection of the connection between the cutter seat 2 and the cutter head 3. It can prevent external boring debris from damaging the internal structure, and can also weaken the swing stress of the cutter head 3 during the overall boring operation.

[0023] Embodiment 4, on the basis of embodiment 3, in order to achieve the stability of the cutter head 3 during deep hole step hole processing, this embodiment further proposes: a receiving inclined groove 40 is provided on the inner wall of the cutter head sleeve 4, the receiving inclined groove 40 is provided at an inclined surface inclined at an angle of 75°, and an avoidance groove 401 is provided through the upper cavity of the receiving inclined groove 40, and the receiving inclined groove 40 and the avoidance groove 401 are respectively provided with six groups and are distributed in a circular array about the central axis of the cutter head sleeve 4; the extension component includes a protective convex ring 42 and a screw disk 421, the protective convex ring 42 is fixedly mounted on the upper surface of the cutter head sleeve 4, and the screw disk 421 The rotating disk 421 is rotatably mounted on the upper side of the protective convex ring 42. The central inner surface of the screwing disk 421 is fixedly connected to a connecting shaft. The outer surface of the lower end of the connecting shaft is fixedly connected to a gear 422. The outer surface of the gear 422 is meshed and rotatably engaged with a gear ring 423. The inner ring surface of the gear ring 423 is fixedly connected to a rotating disk 43. The cross-section of the rotating disk 43 is a "convex" plate-like structure. The upper outer surface of the rotating disk 43 is fixedly connected to a limiting ring 4231. A rotating groove 400 is provided on the side wall of the upper inner ring of the tool head sleeve 4. The inner surface of the rotating groove 400 is rotatably connected to the outer surface of the limiting ring 4231. In this embodiment, after the cutter head 3 completes the processing of the first stepped hole on the upper layer, the radial depth of the cutter head 3 is adjusted to process the second stepped hole. At this time, the cutter head 3 extends into the second stepped hole, and the upper section of the cutter head 3 is located in the boring hole of the first stepped hole. According to the boring hole diameter of the first stepped hole, the expansion component is adjusted to adapt to stepped holes of different diameters. Specifically, the screwing disk 421 is manually rotated so that the connecting shaft drives the gear 422 to rotate together. Under the adaptation of the meshing teeth, the gear ring 423 rotates, so that the rotating disk 43 is fine-tuned according to the rotation The arc groove 430 opened on the disk 43 will drive the inner limiting column 44 to move, and the extended support block 441 will be limited by the rotating groove 400. Then, at this time, multiple groups of extended support blocks 441 can realize variable diameter adjustment. According to the boring diameter of the first step hole, the support plate 442 contacts the bored wall surface thereof to realize the support of the outer hole, enhance the rigidity of the tooling, and avoid the boring tool letting go or vibrating. It should be mentioned that the receiving inclined groove 40 is set as an inclined groove body, which can effectively avoid the adhesion of debris during polishing of the inner side of the step hole while accommodating the extended component.

[0024] Embodiment 5, on the basis of embodiment 4, in order to avoid the tool vibration phenomenon during the boring operation of the tool head 3, this embodiment further proposes that arc grooves 430 are evenly opened on the inner wall of the rotating disk 43, and the inner surface of the arc groove 430 is movably installed with a limiting column 44, and the lower end of the limiting column 44 is fixedly connected with an extended support block 441, and the outer surface of the extended support block 441 is movably connected with the inner wall of the receiving inclined groove 40 and the avoidance groove 401; a buffer groove 4410 is opened on the inner wall of the outer side of the limiting column 44, and a carbon steel and alloy steel block 443 is fixedly installed on the inner wall of the buffer groove 4410, and the outer surface of the carbon steel and alloy steel block 443 is fixedly connected with a support plate 442, and the outer surface of the support plate 442 is movably connected with the inner wall of the buffer groove 4410; In this embodiment, when the equipment is turned on to realize the overall rotation and boring operation of the cutter head 3, the cutter head holder 4 rotates synchronously with the expansion component. At this time, the support plate 442 can achieve the limit support of the tool 351 during the second step hole processing, maintain the centering boring of the multi-layer step holes, and enhance the processing accuracy. The support plate 442 continuously rubs against the wall of the first step hole, and can assist in polishing the inner wall of the preliminary boring to enhance the smoothness of the bored hole. In addition, by adding a carbon steel and alloy steel block 443 to the inner side of the buffer groove 4410, the back end of the support plate 442 is provided with support rigidity, while weakening the vibration during boring, thereby further improving the stability during step hole processing.

[0025] When the tooth bar 321 is in counterclockwise rotation, the movable cylinder 1 33 and the movable cylinder 2 34 move toward each other. During the relative movement of the movable cylinder 2 34, the surface of the limit rod 353 slides, and the tool mounting seat 35 and the tool 351 on one side are driven to move. In this way, the extension distance of the tool 351 is achieved by accurately adjusting the rotation angle of the screw handle 32 to adapt to the boring of the non-diameter stepped hole. Furthermore, when the cutter head 3 has completed the machining of the first stepped hole on the upper layer, the radial depth and axial diameter of the cutter head 3 are adjusted, and then the second stepped hole is machined. At this time, the cutter head 3 extends into the second stepped hole, and the screw disk 421 is manually rotated to make the connecting shaft drive the gear 422 to rotate together. Under the adaptation of the teeth, the gear ring 423 rotates, so that the rotating disk 43 is fine-tuned. According to the arc groove 430 provided on the rotating disk 43, the inner limit column 44 is driven to move, and the extended support block 441 is limited by the rotating groove 400. At this time, multiple groups of extended support blocks 441 can achieve variable diameter adjustment. After the equipment is turned on, when the cutter head 3 is rotated as a whole for boring operation, the cutter head seat 4 rotates synchronously with the extended component. At this time, the support plate 442 can achieve the second The limit support during collective hollow machining maintains the centering boring of the multi-layer stepped holes and enhances the machining accuracy. The support plate 442 continuously rubs against the wall of the first stepped hole, which can assist in polishing the inner wall of the preliminary boring and enhance the smoothness of the bored hole. In addition, by adding a carbon steel and alloy steel block 443 to the inner side of the buffer groove 4410, the back end of the support plate 442 is provided with supporting rigidity, while the vibration during boring is weakened, thereby further improving the stability during step hole machining.

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An adjustable boring tool for step hole machining, comprising a tool body (1), a tool holder (2) being arranged at the lower end of the tool body (1), a tool head (3) being fixedly connected to the lower end of the tool holder (2), characterized in that: The knife body (1) is composed of an upper knife bar (11), a second knife bar (12) and a knife bar sleeve (121); the lower end outer surfaces of the second knife bar (12) and the knife bar sleeve (121) are welded and fixed to the knife seat (2); the inner surface of the knife head (3) is respectively provided with a movable groove (30) and a movable groove (300); a square notch (301) is formed through the center of the movable groove (30) and the movable groove (300); an axial adjustment mechanism is provided on the inner side of the square notch (301); a variable diameter support mechanism is provided on the upper side of the knife head (3); the variable diameter support mechanism includes a knife head sleeve seat (4) and an expansion component.

2. The adjustable boring tool for step hole machining according to claim 1, characterized in that: A cavity (10) is provided on the inner surface of the upper knife rod (11), and a radial adjustment mechanism is provided in the inner cavity of the cavity (10). The radial adjustment mechanism includes a telescopic push rod (13), and the telescopic push rod (13) is fixedly mounted on the inner cavity top surface of the cavity (10). The output end of the telescopic push rod (13) is fixedly connected to the upper end outer surface of the second knife rod (12), and the outer surface of the second knife rod (12) is fixedly connected to the inner surface of the knife rod sleeve (121), and the outer surface of the knife rod sleeve (121) is slidably connected to the inner wall of the cavity (10).

3. The adjustable boring tool for step hole machining according to claim 1, characterized in that: The axial adjustment mechanism comprises a screw handle (32), a movable cylinder 1 (33) and a movable cylinder 2 (34); a gear rod (321) is fixedly mounted on the central outer surface of the screw handle (32); two ends of the screw handle (32) are rotatably connected to the inner wall of the cutter head (3); the movable cylinder 1 (33) is slidably mounted on the inner side of the movable groove 1 (30); the movable cylinder 2 (34) is slidably mounted on the inner side of the movable groove 2 (300); a tooth groove meshing with the outer surface of the gear rod (321) is respectively provided on the lower surface of the movable cylinder 1 (33) and the upper surface of the movable cylinder 2 (34); a fixed block (354) fixedly connected to the inner wall of the movable groove 2 (300) is provided at one end of the movable cylinder 2 (34); an inner side surface of the fixed block (354) is fixedly connected to a limiting rod (353); and an outer surface of the limiting rod (353) is movably connected to the inner wall of the movable cylinder 2 (34).

4. The adjustable boring tool for step hole machining according to claim 3, characterized in that: A connecting rod (352) is fixedly mounted on one end of the limiting rod (353) away from the fixing block (354); the outer surface of the connecting rod (352) is fixedly connected to the inner wall of the second movable cylinder (34); the outer side of the connecting rod (352) is fixedly connected to a tool mounting seat (35) via bolts; a tool (351) is detachably mounted on the lower end of the tool mounting seat (35).

5. The adjustable boring tool for step hole machining according to claim 1, characterized in that: Fastening bolts (31) are respectively provided on the inner walls on both sides of the cutter head seat (4); the cutter head seat (4) is fixedly connected to the outer surface of the cutter head (3) via the fastening bolts (31); and an inner convex plate (41) is fixedly provided on the inner ring side wall of the cutter head seat (4).

6. The adjustable boring tool for step hole machining according to claim 5, characterized in that: An inner wall of the tool head housing (4) is provided with an inclined receiving groove (40), the inclined receiving groove (40) being provided at an inclined surface inclined at an angle of 75°, an escape groove (401) being provided through the upper cavity of the inclined receiving groove (40), and six groups of the inclined receiving grooves (40) and the escape grooves (401) are provided respectively and are distributed in a circular array about the central axis of the tool head housing (4).

7. The adjustable boring tool for step hole machining according to claim 1, characterized in that: The extension component comprises a protective convex ring (42) and a screwing disk (421); the protective convex ring (42) is fixedly mounted on the upper surface of the cutter head sleeve (4); the screwing disk (421) is rotatably mounted on the upper side of the protective convex ring (42); the central inner surface of the screwing disk (421) is fixedly connected to a connecting shaft; the lower end outer surface of the connecting shaft is fixedly connected to a gear (422); the outer surface of the gear (422) is rotatably meshed with a toothed ring (423); the inner ring surface of the toothed ring (423) is fixedly connected to a rotating disk (43); the cross-section of the rotating disk (43) presents a "convex" plate-like structure.

8. The adjustable boring tool for step hole machining according to claim 7, characterized in that: The upper outer surface of the rotating disk (43) is fixedly connected to a limit ring (4231), and a rotation groove (400) is provided on the upper inner ring side wall of the tool head sleeve (4), and the inner surface of the rotation groove (400) is rotatably connected to the outer surface of the limit ring (4231).

9. The adjustable boring tool for step hole machining according to claim 8, characterized in that: The inner wall of the rotating disk (43) is evenly provided with arc grooves (430), the inner surface of the arc groove (430) is movably mounted with a limiting column (44), the lower end of the limiting column (44) is fixedly connected with an extended support block (441), and the outer surface of the extended support block (441) is movably connected to the inner wall of the receiving inclined groove (40) and the avoidance groove (401).

10. The adjustable boring tool for step hole machining according to claim 9, characterized in that: A buffer groove (4410) is provided on the inner wall of the outer side of the limiting column (44); a carbon steel and alloy steel block (443) is fixedly mounted on the inner wall of the buffer groove (4410); a support plate (442) is fixedly connected to the outer surface of the carbon steel and alloy steel block (443); and the outer surface of the support plate (442) is movably connected to the inner wall of the buffer groove (4410).

Images