Cylindrical gear inner hole static pressure expansion centering boring device

Abstract

The application belongs to the technical field of boring device, and particularly relates to a cylindrical gear inner hole static pressure expansion centering boring device, which comprises a boring machine seat, a main shaft box and a feeding platform, the outer side of the output shaft of the main shaft box is provided with a clamping disc, and the outer side of the clamping disc is fixedly provided with a centering column. The synchronous expansion clamping mechanism is arranged, the multi-oil-way uniform oil supply is matched with the slope linkage expansion structure, the multi-point synchronous static pressure inner supporting positioning is realized from the gear inner hole, the traditional outer clamping type clamping mode is replaced, the problems of uneven clamping force of the outer clamping, gear stress deformation and centering eccentricity are avoided, the accurate guiding and limiting structure of the stabilizing rod is matched, the gear workpiece centering coaxiality can be guaranteed to be very high, the workpiece deviation and radial runout problems in the outer side boring process can be completely eliminated, the profile precision and the repeat positioning precision of the gear outer circle and end face boring are greatly improved, and the precise finishing requirement of the gear outer side is effectively met.

Description

Technical Field

[0001] This application relates to the field of boring equipment technology, and in particular to a static pressure expansion centering boring device for the inner hole of a cylindrical gear. Background Technology

[0002] As a core component in the field of mechanical transmission, the machining accuracy of the inner hole of cylindrical gears directly determines the coaxiality of gear assembly, transmission smoothness and service life. Inner hole boring is a key process in the precision machining of cylindrical gears. During the inner hole boring process, the centering accuracy of the workpiece, the clamping stability and the pressure stability during the machining process are the core keys to ensuring the roundness, dimensional accuracy and consistency of the inner hole after boring.

[0003] Currently, most existing cylindrical gear internal boring machines use ordinary mechanical expansion sleeves or fixed chucks to center and clamp the gear internal holes. The machining process typically involves the spindle rotating the gear workpiece while the boring bar is fixed and feeds linearly along the feed platform. Traditional clamping structures have several inherent drawbacks in practical applications: ordinary mechanical expansion sleeves often use a single conical extrusion structure, resulting in uneven force distribution and poor expansion synchronization at different clamping points. This easily leads to radial offset during gear internal hole centering, resulting in low positioning accuracy. This fails to meet the micron-level coaxiality requirements of high-precision gear internal hole machining, and long-term use is prone to wear and jamming, leading to a continuous decline in repeatability.

[0004] Secondly, existing hydrostatic clamping structures mostly employ open hydraulic oil supply circuits, relying solely on a hydraulic pump station to maintain continuous pressure for workpiece clamping. During boring, issues such as machine tool vibration, oil circuit pressure differential fluctuations, and slight hydraulic oil backflow cannot be avoided, easily leading to unstable clamping pressure. Pressure fluctuations cause slight wobbling of the gear workpiece during machining, directly resulting in machining defects such as ripples, out-of-roundness deviations, and poor dimensional consistency in the bored inner hole, significantly reducing the pass rate of gear inner hole finishing. Therefore, a hydrostatic expansion centering boring device for cylindrical gear inner holes needs to be designed. Summary of the Invention

[0005] Therefore, it is necessary to provide a hydrostatic expansion centering boring device for the inner hole of cylindrical gears to address the above-mentioned technical problems.

[0006] To address the aforementioned problems, this invention provides a technical solution for a hydrostatic expansion centering boring device for the inner bore of cylindrical gears:

[0007] A hydrostatic expansion centering boring device for cylindrical gear inner bores includes a boring machine base, a spindle box, and a feed platform. A clamping plate is mounted on the outer side of the output shaft of the spindle box, and a centering column is fixedly mounted on the outer side of the clamping plate. A synchronous expansion clamping mechanism is provided inside the clamping plate. The synchronous expansion clamping mechanism includes a fluid supply ring, an oil delivery bend, and an inclined expansion assembly. The fluid supply ring is rotatably disposed on the outer side of the clamping plate, and an oil delivery bend is fixedly mounted on the lower end of the fluid supply ring. A hydraulic plate is fixedly mounted inside the clamping plate, and multiple evenly distributed oil inlets and outlets are fixedly mounted on the outer side of the hydraulic plate. The openings of the oil inlets and outlets are all located inside the fluid supply ring. The inclined expansion assembly is disposed inside the centering column.

[0008] The boring machine base is equipped with a feed pressure stabilizing mechanism, which includes a closed-circuit box and a hydraulic pump station. The closed-circuit box is fixedly installed on the upper end of the boring machine base, and one end of the closed-circuit box is fixedly connected to the oil delivery bend. The hydraulic pump station is located on the outside of the boring machine base, and the hydraulic pump station is connected to the closed-circuit box through a pipeline.

[0009] Preferably, the synchronous expansion clamping mechanism further includes mounting rings. Two mounting rings are fixedly installed on the outer side of the clamping plate, symmetrically distributed around the liquid supply ring. The mounting rings are connected to the liquid supply rings via bearings, and an oil seal is provided between the mounting rings and the liquid supply rings. The liquid supply rings can simultaneously supply oil to the interior of the hydraulic plate through multiple oil inlets and outlets.

[0010] Preferably, an alloy corrugated sleeve is fixedly installed on the outer side of the hydraulic plate, and a drive plate is fixedly installed on the end of the alloy corrugated sleeve away from the hydraulic plate. A fixing frame is fixedly installed on the inner side of the hydraulic plate, and a double-rod reset frame is slidably connected inside the fixing frame. The two rods of the double-rod reset frame are fixedly installed on one side of the plane of the drive plate. Hydraulic oil enters the interior of the hydraulic plate through the oil inlet and outlet, which can drive the drive plate to move.

[0011] Preferably, a reset spring is provided on the outer side of each of the two rods of the double-rod reset frame. One end of the reset spring is fixedly connected to the fixed frame, and the other end of the reset spring is fixedly connected to the double-rod reset frame. When the hydraulic oil flows back, the reset spring can automatically reset the double-rod reset frame through its elastic force.

[0012] Preferably, the inclined expansion assembly includes an inclined top ring. The inclined top ring is fixedly installed on the outer side of the pipe on the side of the drive disc away from the alloy corrugated sleeve. Multiple evenly distributed support bars are slidably connected inside the centering column. An inclined push bar is fixedly installed at the lower end of the support bar. The inclined push bar is slidably connected to the inclined surface of the inclined top ring. A stabilizing rod is fixedly installed inside the centering column. The stabilizing rod is inserted into the pipe on the outer side of the drive disc. When the drive disc is pushed by hydraulic oil, it drives the inclined top ring to push the inclined push bar to move. The inclined push bar can drive the support bars to move outward of the centering column, thereby clamping the gear workpiece.

[0013] Preferably, a guide frame is fixedly installed on the side of the support bar near the stabilizing rod. A guide pin is slidably connected inside the guide frame, and a second return spring is provided on the outside of the guide pin. The guide pin is fixedly connected to the inner wall of the centering column. The two ends of the second return spring are fixedly connected to the inner walls of the guide frame and the centering column, respectively. During the retraction of the inclined top ring, the originally compressed second return spring can drive the support bar to retract and reset through elastic force.

[0014] Preferably, the feed stabilizing mechanism further includes a closed-circuit ball. The closed-circuit ball is rotatably connected inside the closed-circuit box. A rotating shaft is fixedly installed on the upper end of the closed-circuit ball. A swing arm is fixedly installed on the upper outer side of the rotating shaft. A drive frame is movably connected to the outer side of the eccentric shaft of the swing arm. A hexagonal rod is fixedly installed on the end of the drive frame away from the swing arm. A pressing block is fixedly installed on the end of the hexagonal rod away from the drive frame. During the feed platform's movement, the pressing block can be moved by the fixing bar, the stroke-extending spring, and the push plate. During the movement of the pressing block, the drive frame can be moved by the hexagonal rod. During the movement of the drive frame, the swing arm can be swung by the waist hole. The swing arm drives the closed-circuit ball to rotate through the rotating shaft. The closed-circuit ball can turn the opening to the closed direction to seal the hydraulic circuit, making the hydraulic pressure more stable during the cutting process and preventing backflow.

[0015] Preferably, a support plate is slidably connected to the outer side of the hexagonal rod. The support plate is fixedly installed on the upper end of the boring machine base and contacts the drive frame. A compression spring is provided on the outer side of the hexagonal rod. One end of the compression spring is fixedly connected to the support plate, and the other end of the compression spring is fixedly connected to the compression block. The compression block can compress the compression spring during the pushing process. When the pressure on the compression block is removed, the compression spring can drive the compression block and the hexagonal rod to return to their original positions.

[0016] Preferably, a push plate is in contact with the outer side of the extrusion block, and a double-rod guide is fixedly installed on the side of the push plate away from the extrusion block. A fixing strip is slidably connected to the outer side of the double-rod guide, and the fixing strip is fixedly installed on the outer side of the feed platform. An extension spring is provided on the outer side of each of the two rods of the double-rod guide. One end of the extension spring is fixedly connected to the fixing strip, and the other end of the extension spring is fixedly connected to the push plate. When the extrusion spring is squeezed to a predetermined elastic force value, the extension spring is compressed, which can increase the feed position of the feed platform.

[0017] Preferably, the spindle box is fixedly installed on the upper end of the boring machine base, the upper end of the boring machine base is provided with a feed platform, the upper end of the feed platform is fixedly installed with a tool holder, and the boring bar is installed inside the tool holder by bolts. During operation, the spindle box can drive the gear workpiece to rotate, and at the same time, the feed platform can drive the boring bar to perform boring feed through the tool holder.

[0018] The beneficial effects of this invention are:

[0019] This invention utilizes a synchronous expansion clamping mechanism with a multi-oil-path uniform oil supply and a sloping-plane linkage expansion structure to achieve multi-point synchronous hydrostatic internal support positioning from the gear's inner hole. This replaces the traditional external clamping method, avoiding problems such as uneven clamping force, gear deformation, and centering eccentricity. Simultaneously, the precise guiding and limiting structure of the stabilizing rod ensures extremely high centering and coaxiality of the gear workpiece, completely eliminating workpiece offset and radial runout during the outer boring process. This significantly improves the contour accuracy and repeatability of the gear's outer diameter and end face boring, effectively meeting the precision machining requirements of the gear's outer side.

[0020] This invention adds a feed linkage pressure stabilizing mechanism, which relies on the feed action of the boring machine's feed platform to achieve purely mechanical linkage pressure control. When the boring tool contacts the outer side of the gear and begins cutting, it automatically closes the hydraulic oil circuit, achieving closed constant pressure maintenance throughout the entire outer boring process. This structure can completely eliminate the pressure instability caused by machine tool vibration, oil circuit pressure difference fluctuations, and slight hydraulic oil backflow, ensuring that the inner support clamping force is constant throughout the process. It avoids micro-displacement and micro-loosening of the gear workpiece under the action of the outer cutting force, effectively eliminating defects such as vibration marks, dimensional deviations, and inconsistent contours in outer boring, and significantly improving the machining quality and product qualification rate of the outer side of the gear.

[0021] This invention employs a dynamic-static separation oil supply structure in conjunction with a multi-spring composite reset structure. The oil supply ring rotates with the spindle clamping plate while the external oil circuit remains stationary. Combined with a bearing and oil seal sealing structure, it is suitable for high-precision boring machining conditions, eliminating problems such as oil circuit entanglement, oil leakage, and severe wear, and ensuring long-term stable pressure maintenance of the hydraulic circuit. At the same time, it relies on multiple sets of elastic reset systems to achieve rapid and accurate reset of the clamping mechanism and oil circuit control mechanism, solving the problems of lag reset and unstable clamping in traditional tooling. The equipment operates stably and has a regular machining cycle, making it suitable for mass production of precision boring of the outer side of gears, reducing equipment maintenance costs, and extending the service life of tooling. Attached Figure Description

[0022] Figure 1 This is a three-dimensional representation of the overall structure of a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear, as described in one embodiment. Figure 1 ;

[0023] Figure 2 This is a three-dimensional representation of the overall structure of a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear, as described in one embodiment. Figure 2 ;

[0024] Figure 3 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 1 A magnified view of the local structure;

[0025] Figure 4 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 1 A cross-sectional view of the clamping plate;

[0026] Figure 5 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 4 A three-dimensional diagram of the centering column;

[0027] Figure 6 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 3 A three-dimensional view of the closed-circuit box;

[0028] Figure 7 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 2 A 3D view of the feed and voltage stabilizing mechanism;

[0029] Figure 8 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 7 A 3D view of the drive frame;

[0030] Figure 9 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 4Enlarged view of the A-section structure;

[0031] Figure 10 One embodiment is a hydrostatic expansion centering boring device for the inner bore of a cylindrical gear. Figure 9 A three-dimensional diagram of the support strip.

[0032] In the diagram: 1. Boring machine base; 2. Spindle box; 3. Clamping plate; 4. Centering column; 5. Synchronous expansion clamping mechanism; 6. Feed pressure stabilizing mechanism; 7. Inclined expansion assembly; 8. Feed platform; 9. Tool holder; 10. Boring tool bar; 51. Mounting ring; 52. Fluid supply ring; 53. Oil supply bend; 54. Hydraulic plate; 55. Oil inlet / outlet; 56. Alloy corrugated sleeve; 57. Drive plate; 58. Fixing frame; 59. Double-bar reset frame; 510. Return spring one; 61. 62. Closed-circuit box; 63. Closed-circuit ball; 64. Rotating shaft; 65. Swing arm; 66. Drive frame; 67. Hexagonal rod; 68. Support plate; 69. Extrusion block; 60. Extrusion spring; 610. Fixing bar; 611. Double rod guide frame; 612. Push plate; 613. Extending spring; 614. Hydraulic pump station; 71. Inclined top ring; 72. Support clamping bar; 73. Inclined push bar; 74. Stabilizer bar; 75. Guide frame; 76. Guide pin; 77. Return spring II. Detailed Implementation

[0033] like Figure 1-10 As shown, the specific implementation adopts the following technical solution:

[0034] Example:

[0035] A hydrostatic expansion centering boring device for cylindrical gear inner bores includes a boring machine base 1, a spindle box 2, and a feed platform 8. A clamping plate 3 is mounted on the outer side of the output shaft of the spindle box 2. A centering column 4 is fixedly mounted on the outer side of the clamping plate 3. A synchronous expansion clamping mechanism 5 is provided inside the clamping plate 3. The synchronous expansion clamping mechanism 5 includes a fluid supply ring 52, an oil delivery bend 53, and an inclined expansion assembly 7. The fluid supply ring 52 is rotatably disposed on the outer side of the clamping plate 3. The lower end of the fluid supply ring 52 is fixedly mounted with the oil delivery bend 53. A hydraulic plate 54 is fixedly mounted inside the clamping plate 3. Multiple evenly distributed oil inlet and outlet ports 55 are fixedly installed on the outer side of the hydraulic plate 54. The openings of the oil inlet and outlet ports 55 are all located inside the fluid supply ring 52. The inclined expansion component 7 is set inside the centering column 4. A feed pressure stabilizing mechanism 6 is set on the boring machine base 1. The feed pressure stabilizing mechanism 6 includes a closed-loop box 61 and a hydraulic pump station 614. The closed-loop box 61 is fixedly installed on the upper end of the boring machine base 1. One end of the closed-loop box 61 is fixedly connected to the oil delivery bend 53. The hydraulic pump station 614 is set on the outer side of the boring machine base 1. The hydraulic pump station 614 is connected to the closed-loop box 61 through a pipeline.

[0036] The synchronous expansion clamping mechanism 5 also includes mounting rings 51. Two mounting rings 51, symmetrically distributed around a fluid supply ring 52, are fixedly mounted on the outer side of the clamping plate 3. The mounting rings 51 and the fluid supply rings 52 are connected by bearings, and an oil seal is provided between the mounting rings 51 and the fluid supply rings 52. The fluid supply rings 52 can simultaneously supply oil to the interior of the hydraulic plate 54 through multiple oil inlet and outlet ports 55. An alloy corrugated sleeve 56 is fixedly mounted on the outer side of the hydraulic plate 54. A drive plate 57 is fixedly mounted on the end of the alloy corrugated sleeve 56 away from the hydraulic plate 54. A fixing bracket 58 is fixedly mounted on the inner side of the hydraulic plate 54. A double-rod reset frame 59 is slidably connected inside the fixed frame 58. The two rods of the double-rod reset frame 59 are fixedly installed on one side of the plane of the drive plate 57. Hydraulic oil enters the interior of the hydraulic plate 54 through the oil inlet and outlet 55, which can push the drive plate 57 to move. A reset spring 510 is provided on the outer side of the two rods of the double-rod reset frame 59. One end of the reset spring 510 is fixedly connected to the fixed frame 58, and the other end of the reset spring 510 is fixedly connected to the double-rod reset frame 59. When the hydraulic oil flows back, the reset spring 510 can automatically reset the double-rod reset frame 59 through its elastic force.

[0037] The inclined expansion assembly 7 includes an inclined top ring 71. The inclined top ring 71 is fixedly installed on the outer side of the pipe on the side of the drive disc 57 away from the alloy corrugated sleeve 56. Multiple evenly distributed support bars 72 are slidably connected inside the centering column 4. An inclined push bar 73 is fixedly installed at the lower end of each support bar 72, and the inclined push bar 73 is slidably connected to the inclined surface of the inclined top ring 71. A stabilizing rod 74 is fixedly installed inside the centering column 4 and inserted into the pipe on the outer side of the drive disc 57. During the process of the drive disc 57 being actuated by hydraulic oil, the inclined top ring 71 drives the inclined push bar 73 to move. The push bar 73 can drive the clamping bar 72 to move outward of the centering column 4, thereby clamping the gear workpiece. The side of the clamping bar 72 near the stabilizing rod 74 is fixedly equipped with a guide frame 75. The guide frame 75 is slidably connected to the inside of the guide pin 76. The outside of the guide pin 76 is provided with a return spring 77. The guide pin 76 is fixedly connected to the inner wall of the centering column 4. The two ends of the return spring 77 are fixedly connected to the guide frame 75 and the inner wall of the centering column 4, respectively. During the retraction of the inclined top ring 71, the originally compressed return spring 77 can drive the clamping bar 72 to retract and reset through the elastic force.

[0038] The feed stabilizing mechanism 6 also includes a closed-circuit ball 62. The closed-circuit ball 62 is rotatably connected inside the closed-circuit box 61. A rotating shaft 63 is fixedly installed on the upper end of the closed-circuit ball 62. A swing arm 64 is fixedly installed on the upper outer side of the rotating shaft 63. A drive frame 65 is movably connected to the outer side of the eccentric shaft of the swing arm 64. A hexagonal rod 66 is fixedly installed on the end of the drive frame 65 away from the swing arm 64. A pressing block 68 is fixedly installed on the end of the hexagonal rod 66 away from the drive frame 65. During the feed movement of the feed platform 8, the pressing block 68 can be moved by the fixed bar 610, the stroke-extending spring 613 and the push plate 612. During the movement of the pressing block 68, the drive frame 65 can be moved by the hexagonal rod 66. During the movement of the drive frame 65, the swing arm 64 can be swung by the waist hole. The swing arm 64 drives the closed-circuit ball 62 to rotate through the rotating shaft 63. The closed-circuit ball 62 can turn the opening to the closed direction to seal the hydraulic circuit, making the hydraulic pressure more stable during the cutting process and preventing backflow.

[0039] A support plate 67 is slidably connected to the outer side of the hexagonal rod 66. The support plate 67 is fixedly installed on the upper end of the boring machine base 1 and contacts the drive frame 65. A compression spring 69 is provided on the outer side of the hexagonal rod 66. One end of the compression spring 69 is fixedly connected to the support plate 67, and the other end of the compression spring 69 is fixedly connected to the compression block 68. The compression block 68 can compress the compression spring 69 during the pushing process. When the pressure on the compression block 68 is removed, the compression spring 69 can drive the compression block 68 and the hexagonal rod 66 to return to their original positions. The outer side of the compression block 68 is in contact with the drive frame 65. A double-rod guide 611 is fixedly installed on the side of the push plate 612 away from the extrusion block 68. A fixing strip 610 is slidably connected to the outer side of the double-rod guide 611. The fixing strip 610 is fixedly installed on the outer side of the feed platform 8. An extension spring 613 is provided on the outer side of each of the two rods of the double-rod guide 611. One end of the extension spring 613 is fixedly connected to the fixing strip 610, and the other end of the extension spring 613 is fixedly connected to the push plate 612. When the extrusion spring 69 is extruded to a predetermined elastic force value, the extension spring 613 is compressed, which can increase the feed position of the feed platform 8.

[0040] The spindle box 2 is fixedly installed on the upper end of the boring machine base 1. The upper end of the boring machine base 1 is provided with a feed platform 8. The upper end of the feed platform 8 is fixedly installed with a tool holder 9. The boring bar 10 is installed inside the tool holder 9 by bolts. During the operation, the spindle box 2 can drive the gear workpiece to rotate. At the same time, the feed platform 8 can drive the boring bar 10 to perform boring feed through the tool holder 9.

[0041] The usage state of this invention is as follows: During processing, the cylindrical gear to be processed is fitted onto the outside of the centering column 4. At this time, the synchronous expansion clamping mechanism 5 is in the initial contraction state, the support bar 72 does not contact the inner wall of the gear hole, the hydraulic pump station 614 is in the standby state, the opening of the closed-circuit ball 62 points to the conduction direction, so that the hydraulic oil circuit remains unobstructed, the supply ring 52 is rotatably mounted on the mounting ring 51 on the outside of the clamping plate 3 through the bearing, and an oil seal is provided between the supply ring 52 and the mounting ring 51 to ensure that the high pressure oil does not leak at the rotating interface. The supply ring 52 is fixedly connected to the closed-circuit box 61 through the oil delivery bend 53. When the clamping plate 3 rotates with the spindle box 2, the supply ring 52 rotates relative to the clamping plate 3 but remains stationary relative to the boring machine base 1, thereby introducing the hydraulic oil at the stationary end into the rotating hydraulic plate 54, completing the transition of the hydrostatic oil circuit from the stationary end to the rotating end.

[0042] Start the hydraulic pump station 614. High-pressure hydraulic oil enters the closed-circuit box 61 through the pipeline, and then enters the inner cavity of the supply ring 52 through the oil supply bend 53. The supply ring 52 surrounds the outside of the clamping plate 3. Its inner cavity is simultaneously connected to multiple oil inlet and outlet ports 55 on the outside of the hydraulic plate 54. High-pressure oil enters the hydraulic plate 54 simultaneously through multiple oil inlet and outlet ports 55, realizing multi-point simultaneous oil supply. The high-pressure oil entering the hydraulic plate 54 pushes the drive plate 57 to move axially. The drive plate 57 and the hydraulic plate 54 are sealed and connected by an alloy corrugated sleeve 56. The alloy corrugated sleeve 56 keeps the oil cavity sealed while following the extension and retraction of the drive plate 57. When the drive plate 57 moves, it drives the double rod reset frame 59 to slide synchronously in the fixed frame 58 and compresses the reset spring 510.

[0043] The tubular components on the outer side of the drive disc 57 drive the inclined top ring 71 to move axially synchronously. The inclined surface of the inclined top ring 71 cooperates with the inclined surface of the inclined push bar 73. Through the inclined surface cooperation, the axial motion is converted into radial motion, which pushes multiple evenly distributed support bars 72 to slide outward synchronously along the radial direction of the centering column 4, uniformly contacting and tightening the inner wall of the gear hole, realizing static pressure expansion centering clamping. During this process, the guide frame 75 on the inner side of the support bar 72 compresses the reset spring 77, and the guide pin 76 provides guiding constraint for the radial sliding of the support bar 72, ensuring that the movement trajectory of each support bar 72 is accurate and consistent.

[0044] After the gear workpiece is synchronously tightened, the spindle box 2 starts, driving the clamping plate 3, centering column 4 and the tightened gear workpiece to rotate synchronously. At the same time, the feed platform 8 feeds towards the spindle, and drives the boring bar 10 to perform boring on the outer circle of the rotating gear through the tool holder 9. During the feed process of the feed platform 8, the fixing bar 610 fixedly installed on the outside of the feed platform 8 moves synchronously with the platform. The fixing bar 610 is connected to the push plate 612 through the double rod guide 611 and the stroke extension spring 613. After the feed platform 8 moves a certain distance, the push plate 612 contacts the extrusion block 68.

[0045] After the extrusion block 68 is pushed, it causes the hexagonal rod 66 to slide within the support plate 67, while simultaneously compressing the extrusion spring 69. The hexagonal rod 66 drives the drive frame 65 to move. The drive frame 65 is movably connected to the eccentric shaft of the swing arm 64 through the waist hole, converting linear motion into oscillating motion. This drives the swing arm 64 to oscillate around the rotation axis 63. The rotation axis 63 drives the closed-circuit ball 62 to rotate within the closed-circuit box 61, turning the opening of the closed-circuit ball 62 from the conducting direction to the sealing direction, cutting off the return channel of the hydraulic oil circuit. This locks and seals the oil pressure inside the hydraulic disc 54 during the cutting process, maintaining stable static pressure. The stroke-extending spring 613 begins to compress after the extrusion spring 69 is compressed to a predetermined elastic force value, providing additional feed stroke for the feed platform 8 and ensuring that the extrusion block 68 always maintains the driving state of the closed-circuit ball 62 throughout the entire cutting process.

[0046] After boring, the feed platform 8 retracts in the reverse direction, and the fixing bar 610 retracts with the feed platform 8, removing the thrust on the push plate 612. The compression spring 69 releases its elastic potential energy, pushing the compression block 68 and the hexagonal rod 66 to slide back to their original positions. The hexagonal rod 66 drives the drive frame 65 to move in the reverse direction, driving the swing arm 64 to swing in the reverse direction. The rotating shaft 63 drives the closed-circuit ball 62 to rotate back to its original position, causing the opening of the closed-circuit ball 62 to turn back to the conduction direction. The hydraulic pipeline is restored to unobstructed flow, and the hydraulic oil inside the hydraulic plate 54 flows through the inlet and outlet ports 55. The fluid supply ring 52 and the oil delivery bend 53 return to the closed-circuit box 61 and the hydraulic pump station 614. The first reset spring 510 releases its elastic potential energy, pushing the double rod reset frame 59 to drive the drive disc 57 to axially reset. The drive disc 57 drives the inclined top ring 71 to retract. The second reset spring 77 releases its elastic potential energy, pulling each support clamp 72 radially inward through the guide frame 75, separating it from the inner wall of the gear hole, releasing the workpiece. The operator can then remove the bored gear from the centering column 4, completing a full work cycle.

[0047] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

Claims

1. A hydrostatic expansion centering boring device for the inner bore of a cylindrical gear, comprising a boring machine base (1), a spindle box (2), and a feed platform (8), wherein a clamping plate (3) is mounted on the outer side of the output shaft of the spindle box (2), and a centering column (4) is fixedly mounted on the outer side of the clamping plate (3), characterized in that: The clamping plate (3) is provided with a synchronous expansion clamping mechanism (5). The synchronous expansion clamping mechanism (5) includes a liquid supply ring (52), an oil delivery bend (53), and an inclined expansion assembly (7). The liquid supply ring (52) is rotatably disposed on the outside of the clamping plate (3). The lower end of the liquid supply ring (52) is fixedly installed with an oil delivery bend (53). The clamping plate (3) is fixedly installed with a hydraulic plate (54). The outside of the hydraulic plate (54) is fixedly installed with multiple evenly distributed oil inlets and outlets (55). The openings of the oil inlets and outlets (55) are all located inside the liquid supply ring (52). The inclined expansion assembly (7) is disposed inside the centering column (4). The boring machine base (1) is provided with a feed pressure stabilizing mechanism (6). The feed pressure stabilizing mechanism (6) includes a closed-circuit box (61) and a hydraulic pump station (614). The closed-circuit box (61) is fixedly installed on the upper end of the boring machine base (1). One end of the closed-circuit box (61) is fixedly connected to the oil delivery bend (53). The hydraulic pump station (614) is located on the outside of the boring machine base (1). The hydraulic pump station (614) is connected to the closed-circuit box (61) through a pipeline.

2. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 1, characterized in that: The synchronous expansion clamping mechanism (5) also includes a mounting ring (51). Two mounting rings (51) are fixedly installed on the outer side of the clamping plate (3) and are symmetrically distributed around the liquid supply ring (52). The mounting ring (51) and the liquid supply ring (52) are connected by bearings, and an oil seal is provided between the mounting ring (51) and the liquid supply ring (52).

3. The cylindrical gear inner hole hydrostatic expansion centering boring device according to claim 2, characterized in that: An alloy corrugated sleeve (56) is fixedly installed on the outer side of the hydraulic disc (54). A drive disc (57) is fixedly installed on the end of the alloy corrugated sleeve (56) away from the hydraulic disc (54). A fixing frame (58) is fixedly installed on the inner side of the hydraulic disc (54). A double-rod reset frame (59) is slidably connected inside the fixing frame (58). Both rods of the double-rod reset frame (59) are fixedly installed on one side of the plane of the drive disc (57).

4. The cylindrical gear inner hole hydrostatic expansion centering boring device according to claim 3, characterized in that: The two rods of the double-rod reset frame (59) are each provided with a reset spring (510) on the outside. One end of the reset spring (510) is fixedly connected to the fixed frame (58), and the other end of the reset spring (510) is fixedly connected to the double-rod reset frame (59).

5. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 3, characterized in that: The inclined expansion assembly (7) includes an inclined top ring (71). The inclined top ring (71) is fixedly installed on the outside of the pipe on the side of the drive disk (57) away from the alloy corrugated sleeve (56). Multiple evenly distributed support bars (72) are slidably connected inside the centering column (4). An inclined push bar (73) is fixedly installed at the lower end of the support bar (72). The inclined push bar (73) is slidably connected to the inclined surface of the inclined top ring (71). A stabilizing rod (74) is fixedly installed inside the centering column (4). The stabilizing rod (74) is inserted into the inside of the pipe outside the drive disk (57).

6. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 5, characterized in that: Each of the support bars (72) has a guide frame (75) fixedly installed on the side near the stabilizer bar (74). The guide frame (75) has a guide pin (76) slidably connected inside. The guide pin (76) has a return spring (77) on its outer side. The guide pin (76) is fixedly connected to the inner wall of the centering column (4). The two ends of the return spring (77) are fixedly connected to the inner walls of the guide frame (75) and the centering column (4), respectively.

7. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 1, characterized in that: The feed stabilizing mechanism (6) also includes a closed-circuit ball (62). The closed-circuit ball (62) is rotatably connected inside the closed-circuit box (61). A rotating shaft (63) is fixedly installed on the upper end of the closed-circuit ball (62). A swing arm (64) is fixedly installed on the upper outer side of the rotating shaft (63). A drive frame (65) is movably connected to the outer side of the eccentric shaft of the swing arm (64). A hexagonal rod (66) is fixedly installed on the end of the drive frame (65) away from the swing arm (64). An extrusion block (68) is fixedly installed on the end of the hexagonal rod (66) away from the drive frame (65).

8. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 7, characterized in that: A support plate (67) is slidably connected to the outer side of the hexagonal rod (66). The support plate (67) is fixedly installed on the upper end of the boring machine base (1). The support plate (67) is in contact with the drive frame (65). A compression spring (69) is provided on the outer side of the hexagonal rod (66). One end of the compression spring (69) is fixedly connected to the support plate (67), and the other end of the compression spring (69) is fixedly connected to the compression block (68).

9. The cylindrical gear internal bore hydrostatic expansion centering boring device according to claim 7, characterized in that: The outer side of the extrusion block (68) is in contact with a push plate (612). A double rod guide (611) is fixedly installed on the side of the push plate (612) away from the extrusion block (68). A fixing strip (610) is slidably connected to the outer side of the double rod guide (611). The fixing strip (610) is fixedly installed on the outer side of the feed platform (8). An extension spring (613) is provided on the outer side of each of the two rods of the double rod guide (611). One end of the extension spring (613) is fixedly connected to the fixing strip (610), and the other end of the extension spring (613) is fixedly connected to the push plate (612).

10. The cylindrical gear inner hole hydrostatic expansion centering boring device according to claim 1, characterized in that: The spindle box (2) is fixedly installed on the upper end of the boring machine base (1). The upper end of the boring machine base (1) is provided with a tool feed platform (8). The upper end of the tool feed platform (8) is fixedly installed with a tool holder (9). The tool holder (9) is installed with a boring bar (10) inside by bolts.

Images