High-precision tool expanding mechanism of numerical control expanding and honing machine

Abstract

This application discloses a high-precision tool-expanding mechanism for a CNC honing machine, mainly composed of a spindle box, spindle motor, servo cylinder, grating ruler, push rod, spline shaft, and spline sleeve. When the servo cylinder operates, the servo motor drives the lead screw pair to rotate, causing the lead screw to move synchronously axially within the mounting base, driving the connecting sleeve and sliding sleeve. Combined with real-time displacement accuracy monitoring and signal feedback from the grating ruler, this improves the tool-expanding displacement error and repeatability, meeting the honing requirements of precision parts. Furthermore, the coordination between the servo cylinder, push rod, spline shaft, and spline sleeve eliminates the response lag of hydraulic transmission and the backlash problem of mechanical transmission, resulting in a fast tool-expanding and receiving response time. During long-term continuous processing, it is minimally affected by factors such as temperature and vibration, reducing tool-expanding accuracy fluctuations, decreasing batch processing defect rates, and lowering maintenance costs. This invention effectively improves tool-expanding accuracy and provides a fast response speed.

Description

Technical Field

[0001] This application relates to the technical field of honing machine blade raising mechanism, and in particular to a high-precision blade raising mechanism for a CNC honing machine. Background Technology

[0002] CNC honing machines are key equipment for precision internal hole machining. The honing mechanism, as its core actuator, mainly functions to drive the honing abrasive strip to expand and retract radially. The honing is achieved through the contact between the abrasive strip and the inner hole of the workpiece. The honing accuracy directly determines key indicators such as the dimensional accuracy, roundness, cylindricity, and surface roughness of the inner hole of the workpiece.

[0003] Currently, the tool-expanding mechanisms of existing CNC honing machines are mainly divided into two types: hydraulic and mechanical. Hydraulic tool-expanding mechanisms suffer from drawbacks such as insufficient precision, slow response, and poor stability. Mechanical tool-expanding mechanisms often use wedge blocks, gears, or lead screws for transmission. Inevitably, there are mechanical backlashes between these transmission pairs. After multiple tool expansions and retractions, these backlashes gradually increase, leading to a decrease in tool repeatability accuracy. Actual measured repeatability errors exceed 0.008mm. Furthermore, they generally lack effective precision monitoring and feedback mechanisms, making it impossible to monitor tool displacement and abrasive strip stress in real time. Once precision deviations occur, timely correction is impossible, resulting in defective workpieces in batches and increased production costs. Summary of the Invention

[0004] This application proposes a high-precision blade-expanding mechanism for a CNC honing machine, which has the advantages of improving blade-expanding accuracy, fast response speed, and automatic lubrication, thereby solving the problems of insufficient accuracy and lag mentioned in the background art.

[0005] To achieve the above objectives, this application adopts the following technical solution: a high-precision blade-expanding mechanism for a CNC honing machine, comprising a spindle box, a spindle motor, and a servo electric cylinder. The top of the spindle box is fixedly connected to the spindle motor. The output shaft end of the spindle motor is internally connected to a drive gear. A driven gear is rotatably arranged inside the spindle box. A toothed belt is sleeved between the outer ring of the driven gear and the outer ring of the drive gear. A mounting base is fixedly connected to the top of the spindle box on one side of the spindle motor, corresponding to the position of the driven gear. The top of the mounting base is fixedly... A servo electric cylinder is fixedly connected, and the servo electric cylinder integrates a servo motor, a lead screw, and a lead screw pair. The output shaft end of the servo motor is directly connected to the lead screw pair, and the lead screw is threadedly sleeved inside the lead screw pair. A connecting sleeve is fixedly connected to the bottom of the lead screw, and a sliding sleeve is connected to the bottom of the connecting sleeve. A grating ruler is fixedly connected to the outer surface of the sliding sleeve and is located outside the mounting base. A push rod is rotatably sleeved inside the sliding sleeve. A splined shaft is rotatably sleeved inside the spindle box, and a splined sleeve is sleeved inside the splined shaft. An automatic lubrication device is installed between the end face of the splined sleeve and the splined shaft.

[0006] With the above structural setup, the servo motor integrated inside the servo cylinder drives the lead screw pair directly. As the lead screw rotates within the lead screw pair's internal thread, it drives the connecting sleeve and sliding sleeve to move axially synchronously. Furthermore, through the bearing A set between the sliding sleeve and the push rod, the push rod can rotate while being driven axially by the sliding sleeve. In addition, the outer ring of the sliding sleeve is equipped with a grating ruler, which can monitor the positional accuracy of the movement, provide real-time feedback and correct the axial positioning accuracy, and improve the accuracy of the tool expansion displacement error and repeatability positioning.

[0007] Furthermore, a bearing A is installed between the inner ring of the sliding sleeve and the outer ring of the end of the push rod, and a cutting tool is connected to the bottom of the push rod.

[0008] With the above structural setup, the servo motor drives the lead screw pair directly, the lead screw moves axially, the lead screw moves the connecting sleeve and sliding sleeve axially, and the sliding sleeve moves the push rod sleeved inside bearing A synchronously.

[0009] Furthermore, the end of the spline shaft is fixedly connected to the driven gear, and bearings B are symmetrically fitted between the outer ring of the spline shaft and the inside of the spindle box. The bottom of the spline shaft is connected to a tool connecting sleeve on the outer ring of the push rod. The spline shaft is hollow and located on the outer ring of the push rod.

[0010] With the above structural configuration, the driven gear rotates through the transmission of the toothed belt, and synchronously drives the spline shaft to rotate inside the bearing B. The spline shaft transmits circumferential torque through the spline sleeve connection with the spline sleeve, and drives the push rod to rotate through the spline sleeve.

[0011] Furthermore, the spline sleeve is fixedly connected to the push rod, and the outer side of the spline sleeve is splined to the inner ring of the spline shaft.

[0012] With the above structural design, when the spline shaft is working, the spline sleeve is driven to rotate synchronously through the rolling friction of the spline, thereby driving the push rod to make selection. This allows the push rod to move smoothly axially and transmit the torque of the round shaft through the spline connection, so that the push rod and the spline shaft maintain synchronous speed and do not generate relative rotation. Compared with the sliding friction of transmission, this reduces the loss.

[0013] Furthermore, the automatic lubrication device includes a top plug and a micro oil storage chamber. The top plug is fixedly installed on the inner wall end face of the spline shaft. The top plug has a conical cross-section. The micro oil storage chamber is installed on the top end face of the spline sleeve. The top plug and the micro oil storage chamber are both located on the outer ring of the push rod. The top plug and the micro oil storage chamber are positioned correspondingly. The automatic lubrication device has ring plates on both the inner and outer ring surfaces of the micro oil storage chamber, and is fixedly connected to the top end face of the spline sleeve.

[0014] With the above structural configuration, the servo electric cylinder drives the lead screw to rotate through the servo motor, and then raises the position of the push rod through the connecting sleeve and sliding sleeve. The push rod drives the position of the micro oil storage chamber to rise through the spline sleeve, so that the lower end of the top plug squeezes the upper end of the micro oil storage chamber.

[0015] Furthermore, the outer ring plate has uniformly formed oil guide grooves on its surface, and the outer ring surface of the micro oil storage chamber has uniformly formed centrifugal oil throwing ports, with the centrifugal oil throwing ports corresponding to the oil guide grooves. A one-way valve is installed inside the centrifugal oil throwing ports.

[0016] With the above structural design, after the top plug and the micro oil storage chamber are squeezed together, the grease inside the micro oil storage chamber is squeezed out through the one-way valve inside the centrifugal oil slinger to the oil guide groove. When the working rotation is performed, when the spline shaft drives the push rod to rotate through the spline sleeve, the centrifugal force of rotation helps the lubricating oil inside the oil guide groove to be evenly distributed on the friction pair surface between the spline shaft and the spline sleeve.

[0017] This application provides a high-precision tool-expanding mechanism for a CNC honing machine. By incorporating a spindle box, spindle motor, servo cylinder, grating ruler, push rod, splined shaft, and splined sleeve, the servo cylinder drives the lead screw pair to rotate. This causes the lead screw, located inside the mounting base, to synchronously move the connecting sleeve and sliding sleeve axially. Combined with real-time displacement accuracy monitoring and signal feedback from the grating ruler, the mechanism improves tool-expanding displacement error and repeatability, meeting the honing requirements of precision parts. Furthermore, the coordination between the servo cylinder, push rod, splined shaft, and splined sleeve eliminates the response lag of hydraulic transmission and the backlash of mechanical transmission, resulting in rapid tool-expanding and receiving response times. During long-term continuous processing, it is minimally affected by factors such as temperature and vibration, reducing tool-expanding accuracy fluctuations, decreasing batch processing defect rates, and lowering maintenance costs. This achieves the effects of improved tool-expanding accuracy and faster response speed.

[0018] This application provides a high-precision tool-expanding mechanism for a CNC honing machine. The mechanism includes a splined shaft, splined sleeve, push rod, and automatic lubrication device. A servo electric cylinder drives a lead screw via a servo motor, which in turn raises the push rod through a connecting sleeve and sliding sleeve. This push rod, via the splined sleeve, raises the position of a miniature oil storage chamber, causing the lower end of the top plug to press against the upper end of the miniature oil storage chamber. The grease inside the miniature oil storage chamber is squeezed out through a one-way valve inside the centrifugal oil outlet to the oil guide groove. During operation, as the splined shaft rotates, the centrifugal force helps to evenly distribute the lubricating oil in the oil guide groove onto the friction pair surface between the splined shaft and the splined sleeve. Automatic lubrication is achieved by raising the splined sleeve during the tool retraction phase to prepare for the next operation, thus realizing both automatic lubrication and centrifugal distribution. Attached Figure Description

[0019] The accompanying drawings, which form part of this specification, illustrate embodiments disclosed in this application and, together with the specification, serve to explain the principles disclosed in this application.

[0020] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a first-view schematic diagram of the internal structure of the spindle box of the present invention; Figure 3 This is a second time-period schematic diagram of the internal structure of the spindle box of the present invention; Figure 4 This is an internal view of the spline shaft and spline sleeve structure of the present invention; Figure 5 This is a schematic diagram of the internal spline sleeve and push rod of the spline shaft structure of the present invention; Figure 6 This is a schematic diagram of the internal structure of the automatic lubrication device of the present invention.

[0021] The components are as follows: 1. Spindle box; 11. Driven gear; 12. Gear belt; 2. Spindle motor; 21. Drive gear; 3. Mounting base; 4. Servo electric cylinder; 41. Connecting sleeve; 42. Sliding sleeve; 5. Grating ruler; 6. Push rod; 61. Cutting tool; 7. Splined shaft; 71. Cutting tool connecting sleeve; 8. Splined sleeve; 9. Automatic lubrication device; 91. Top plug; 92. Miniature oil storage chamber; 93. Ring plate; 94. Oil guide groove; 95. Centrifugal oil slinger. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] Please see Figures 1-4A high-precision blade-expanding mechanism for a CNC honing machine includes a spindle box 1, a spindle motor 2, and a servo cylinder 4. The spindle motor 2 is fixedly connected to the top of the spindle box 1. The output shaft end of the spindle motor 2 is internally connected to a drive gear 21. A driven gear 11 is rotatably mounted inside the spindle box 1. A toothed belt 12 is sleeved between the outer ring of the driven gear 11 and the outer ring of the drive gear 21. A mounting base 3 is fixedly connected to the top of the spindle box 1 on one side of the spindle motor 2, corresponding to the position of the driven gear 11. The servo cylinder 4 is fixedly connected to the top of the mounting base 3. The servo cylinder 4 integrates a servo motor, a high-precision lead screw, and a lead screw pair. The design of the servo electric cylinder 4 differs from that of ordinary transmissions. The rotation of the servo motor drives the precision lead screw to rotate, and the lead screw moves axially to achieve high-precision axial movement. The output shaft of the servo motor is directly connected to the lead screw pair, and the lead screw is threaded inside the lead screw pair. The bottom of the lead screw is fixedly connected to the connecting sleeve 41, and the bottom of the connecting sleeve 41 is connected to the sliding sleeve 42. The outer surface of the sliding sleeve 42 is fixedly connected to the grating ruler 5, which is located outside the mounting base 3. The sliding sleeve 42 is rotatably sleeved with the push rod 6. The spindle box 1 is rotatably sleeved with the spline shaft 7. The spline shaft 7 is splined with the spline sleeve 8. An automatic lubrication device 9 is installed between the end face of the spline sleeve 8 and the spline shaft 7.

[0024] The grating ruler 5 can monitor the axial displacement in real time. The axial displacement has a certain proportional relationship with the cutting edge expansion. It controls the cutting edge expansion and the stress state of the abrasive strip. The feedback adjustment module realizes dynamic compensation and solves the error defects that existing technicians cannot correct in real time.

[0025] The servo motor integrated inside the servo cylinder 4 drives the lead screw pair directly. As the lead screw rotates within the lead screw pair's internal thread, it drives the connecting sleeve 41 and the sliding sleeve 42 to move axially synchronously. Through the bearing A set between the sliding sleeve 42 and the push rod 6, the push rod 6 can rotate while being driven axially by the sliding sleeve 42. Furthermore, the outer ring of the sliding sleeve 42 is equipped with a grating ruler 5, which can monitor the positional accuracy of the movement, provide real-time feedback and correct the axial positioning accuracy, and improve the accuracy of the cutting tool displacement error and repeatability.

[0026] The main spindle motor 2 drives the drive gear 21 to rotate. The drive gear 21 drives the driven gear 11 to rotate synchronously with the spline shaft 7 through the sleeve of the toothed belt 12. The spline shaft 7 is located inside the spindle box 1 and rotates through the bearing B. It rotates synchronously with the spline sleeve 8 through the spline sleeve and the rolling friction of the spline drives the spline sleeve 8 to rotate synchronously. The spline sleeve 8 rotates the push rod 6 through the connection between it and the push rod 6. The push rod 6 moves axially through the connection between it and the sliding sleeve 42. The spline fit between the spline sleeve 8 and the spline shaft 7 makes the axial movement smoother. The push rod 6 transmits the circular shaft torque through the spline sleeve between the spline sleeve 8 and the spline shaft 7, realizing circumferential rotation and maintaining synchronous rotation with the spline shaft 7.

[0027] Please see Figures 1-3 A bearing A is installed between the inner ring of the sliding sleeve 42 and the outer ring of the end of the push rod 6. The connecting sleeve 41 and the sliding sleeve 42 are driven to move axially through the lead screw, thereby driving the push rod 6 to move and rotate axially. A cutter 61 is connected to the bottom of the push rod 6.

[0028] The servo motor drives the lead screw pair through direct connection. The lead screw moves axially, and the movement of the lead screw drives the connecting sleeve 41 and the sliding sleeve 42 to move axially. The sliding sleeve 42 drives the push rod 6, which is sleeved inside the bearing A, to move synchronously, and cooperates with the grating ruler 5 to correct the axial positioning accuracy.

[0029] Please see Figures 1-4 The end of the spline shaft 7 is fixedly connected to the driven gear 11. The outer ring of the spline shaft 7 is symmetrically fitted with bearings B between it and the inside of the spindle box 1. The bottom of the spline shaft 7 is connected to the tool connecting sleeve 71 on the outer ring of the push rod 6, so that when the spindle motor 2 drives the driven gear 11 to rotate through the drive gear 21, it can synchronously drive the spline shaft 7 to rotate. The spline shaft 7 is hollow and is located on the outer ring of the push rod 6.

[0030] Driven gear 11 rotates via gear belt 12 and synchronously drives spline shaft 7 to rotate inside bearing B. Spline shaft 7 transmits circumferential torque through spline sleeve 8, and drives push rod 6 to rotate through spline sleeve 8.

[0031] Please see Figures 1-5 The spline sleeve 8 is fixedly connected to the push rod 6. The outer part of the spline sleeve 8 is splined to the inner ring of the spline shaft 7. When the spline shaft 7 is working, the spline sleeve 8 is driven to rotate synchronously through the rolling friction of the spline, thereby driving the push rod 6 to make selection. This allows the push rod 6 to move smoothly axially and transmit the torque of the round shaft through the spline connection, so that the push rod 6 and the spline shaft 7 maintain synchronous speed and do not generate relative rotation. Compared with the transmission sliding friction, this reduces the loss and improves the stability.

[0032] Please see Figures 1-6 The automatic lubrication device 9 includes a top plug 91 and a miniature oil storage chamber 92. The top plug 91 is fixedly installed on the inner wall end face of the spline shaft 7. The top plug 91 has a conical cross-section. The miniature oil storage chamber 92 is installed on the top end face of the spline sleeve 8. Both the top plug 91 and the miniature oil storage chamber 92 are located on the outer ring of the push rod 6. The positions of the top plug 91 and the miniature oil storage chamber 92 are corresponding. The automatic lubrication device 9 has ring plates 93 on both the inner and outer ring surfaces of the miniature oil storage chamber 92, and they are fixedly connected to the top end face of the spline sleeve 8.

[0033] The miniature oil storage chamber 92 is filled with grease. Initially, the lower end of the top plug 91 contacts the upper end of the miniature oil storage chamber 92. After the work is completed, the servo electric cylinder 4 drives the lead screw to rotate through the servo motor, and then lifts the position of the push rod 6 through the connecting sleeve 41 and the sliding sleeve 42. The push rod 6 drives the position of the miniature oil storage chamber 92 to rise through the spline sleeve 8, so that the lower end of the top plug 91 squeezes the upper end of the miniature oil storage chamber 92.

[0034] Please see Figures 1-6 The outer ring plate 93 has uniformly arranged oil guide grooves 94 on its surface. The outer ring surface of the micro oil storage chamber 92 has uniformly arranged centrifugal oil throwing ports 95 on its outer ring. The centrifugal oil throwing ports 95 and the oil guide grooves 94 are positioned correspondingly. A one-way valve is installed inside the centrifugal oil throwing ports 95.

[0035] The gap between the oil guide groove 94 and the spline shaft 7 and spline sleeve 8 is connected. After the top plug 91 is squeezed between the micro oil storage chamber 92, the grease inside the micro oil storage chamber 92 is squeezed out through the one-way valve inside the centrifugal oil throwing port 95 to the oil guide groove 94. When the spline shaft 7 drives the push rod 6 to rotate through the spline sleeve 8 during operation, the centrifugal force of rotation helps the lubricating oil inside the oil guide groove 94 to be evenly distributed on the friction pair surface between the spline shaft 7 and the spline sleeve 8.

[0036] Based on the above description, automatic lubrication can be achieved with each operation. When the spline sleeve 8 is in the initial position inside the spline shaft 7, that is, when the lower end of the top plug 91 is in contact with the upper end of the micro oil storage chamber 92, the spline sleeve 8 is lifted upward by retracting the tool 61 during operation to prepare for the next operation, thus achieving automatic lubrication. After stopping work, the spline sleeve 8 drives the miniature oil storage chamber 92 back to its initial position. Due to the design of the one-way valve, the interior of the miniature oil storage chamber 92 is slightly concave downwards. During the next lubrication, a slightly larger lifting amount is required to squeeze out the lubricating oil. That is, the amount of grease squeezed out is directly proportional to the height accuracy of the push rod 6 driving the spline sleeve 8 to rise. In other words, the greater the rise, the more lubricating oil is squeezed out, and the more sufficient the lubrication is on the friction pair surface of the spline shaft 7 and the spline sleeve 8, thus achieving adaptive lubrication.

[0037] The automatic lubrication device 9 uses the contraction force of the spline sleeve 8 driven by the push rod 6 as a power source, combined with centrifugal force, to achieve pump-free automatic lubrication. It does not require an additional lubrication pump or control unit, solving the problems of insufficient lubrication and troublesome maintenance in traditional mechanisms, greatly improving the service life of spline sleeves, and reducing accuracy drift caused by wear.

[0038] When the servo cylinder 4 is working, the servo motor drives the lead screw pair to rotate, which in turn causes the lead screw to move synchronously axially inside the mounting base 3, driving the connecting sleeve 41 and the sliding sleeve 42. With the real-time displacement accuracy monitoring and signal feedback of the grating ruler 5, compared with the existing hydraulic and mechanical tool expansion mechanisms, the tool expansion displacement error and repeatability error are improved, which can meet the honing requirements of precision parts.

[0039] Furthermore, the coordination between the servo electric cylinder 4, push rod 6, spline shaft 7, and spline sleeve 8 eliminates the response lag of hydraulic transmission and the gap problem of mechanical transmission, making the response time of tool expansion and reception fast. Moreover, during long-term continuous processing, it is minimally affected by factors such as temperature and vibration, reducing the fluctuation of tool expansion accuracy, reducing the batch processing defect rate, and lowering maintenance costs.

Claims

1. A high-precision honing tool mechanism for a CNC honing machine, characterized in that, The assembly includes a spindle box (1), a spindle motor (2), and a servo cylinder (4). The top of the spindle box (1) is fixedly connected to the spindle motor (2). The output shaft end of the spindle motor (2) is internally connected to a drive gear (21). A driven gear (11) is rotatably mounted inside the spindle box (1). A toothed belt (12) is sleeved between the outer ring of the driven gear (11) and the outer ring of the drive gear (21). A mounting base (3) is fixedly connected to the top of the spindle box (1) on one side of the spindle motor (2), corresponding to the position of the driven gear (11). A servo cylinder (4) is fixedly connected to the top of the mounting base (3). The electric cylinder (4) integrates a servo motor, a lead screw, and a lead screw pair. The output shaft end of the servo motor is directly connected to the lead screw pair. The lead screw is threaded inside the lead screw pair. A connecting sleeve (41) is fixedly connected to the bottom of the lead screw. A sliding sleeve (42) is connected to the bottom of the connecting sleeve (41). A grating ruler (5) is fixedly connected to the outer surface of the sliding sleeve (42) and is located outside the mounting base (3). A push rod (6) is rotatably sleeved inside the sliding sleeve (42). A spline shaft (7) is rotatably sleeved inside the spindle box (1). A spline sleeve (8) is sleeved inside the spline shaft (7). An automatic lubrication device (9) is installed between the end face of the spline sleeve (8) and the spline shaft (7).

2. The high-precision honing mechanism of the CNC honing machine according to claim 1, characterized in that, A bearing A is installed between the inner ring of the sliding sleeve (42) and the outer ring of the end of the push rod (6), and a cutting tool (61) is connected to the bottom of the push rod (6).

3. The high-precision blade expanding mechanism of the CNC honing machine according to claim 2, characterized in that, The end of the spline shaft (7) is fixedly connected to the driven gear (11). The outer ring of the spline shaft (7) and the inside of the spindle box (1) are symmetrically fitted with bearings B. The bottom of the spline shaft (7) is connected to the outer ring of the push rod (6) with a tool connecting sleeve (71). The spline shaft (7) is hollow and located on the outer ring of the push rod (6).

4. The high-precision blade expanding mechanism of the CNC honing machine according to claim 3, characterized in that, The spline sleeve (8) is fixedly connected to the push rod (6), and the outside of the spline sleeve (8) is splined with the inner ring of the spline shaft (7).

5. The high-precision honing tool mechanism of the CNC honing machine according to claim 4, characterized in that, The automatic lubrication device (9) includes a top plug (91) and a micro oil storage chamber (92). The top plug (91) is fixedly installed on the inner wall end face of the spline shaft (7). The top plug (91) has a conical cross-section. The micro oil storage chamber (92) is installed on the top end face of the spline sleeve (8). The top plug (91) and the micro oil storage chamber (92) are both located on the outer ring of the push rod (6). The top plug (91) and the micro oil storage chamber (92) are positioned correspondingly. The automatic lubrication device (9) has ring plates (93) on both the inner and outer ring surfaces of the micro oil storage chamber (92), and is fixedly connected to the top end face of the spline sleeve (8).

6. The high-precision honing mechanism of the CNC honing machine according to claim 5, characterized in that, The outer ring plate (93) has a uniformly arranged oil guide groove (94) on its surface. The outer ring surface of the micro oil storage chamber (92) has a uniformly arranged centrifugal oil throwing port (95) on its outer ring. The centrifugal oil throwing port (95) and the oil guide groove (94) are positioned correspondingly. A one-way valve is provided inside the centrifugal oil throwing port (95).

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