System and method for monitoring working state of intermediate injection direct connection main shaft

Abstract

The invention relates to the technical field of machining center spindles, in particular to a system and method for monitoring the working state of a middle-injection direct-connection spindle, and the system comprises a pull rod, a mandrel and a sleeve which are sequentially and coaxially arranged from inside to outside. A clamping assembly is arranged at one end of the mandrel to clamp a cutter; air injection channels are formed in the pull rods; the pre-tightening assembly comprises a spring and a contact bead which are arranged at one end, close to the clamping assembly, of the mandrel; a through accommodating space is formed in the fixed barrel; a plurality of grooves are formed in one end, far away from the mandrel, of the fixed barrel; the clamping barrel is arranged in the accommodating space, and the outer wall of the clamping barrel abuts against the contact bead; the clamping barrel has a through space; the ball head is arranged at one end of the clamping barrel away from the mandrel; the ball seat is fixedly connected with the fixed barrel and is rotationally connected with the ball head; through holes are formed in the centers of the ball head and the ball seat; the pressing plate is installed at the end, away from the mandrel, of the fixing barrel and fixedly connected with the clamping barrel through a fixing rod. Holes are formed in the centers of the pressing plates; the pressing plate contacts the pressure sensor. Whether the interior of the spindle is bent or not is effectively monitored, and monitoring precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of machining center spindles, and in particular to a system and method for monitoring the working state of a central injection direct-connected spindle. Background Art

[0002] In the modern machinery manufacturing industry, the machining center is the core of efficient and automated production equipment, and its performance is directly related to machining accuracy, efficiency and product quality; the center-jet direct-connected spindle is a high-performance spindle type specially designed for machining centers. Its characteristic is that the drive motor is directly connected to the spindle, which reduces the intermediate links in the transmission chain, thereby improving energy transmission efficiency and response speed. It is one of the key components of the machining center.

[0003] Traditional spindle monitoring methods can no longer meet the growing demand; especially for monitoring subtle changes inside the spindle, such as whether the spindle is bent or deformed. Traditional methods often ignore these subtle differences due to insufficient sensitivity, resulting in the inability to provide timely warnings, which may lead to serious processing errors or even equipment failures.

[0004] Therefore, there is an urgent need for a system and method for monitoring the working status of a center-jet direct-connected spindle, which provides strong support for improving the reliability and intelligence level of the machining center. Summary of the invention

[0005] The present invention provides a system and method for monitoring the working state of a central injection direct-connected spindle, which can effectively monitor whether the spindle has problems such as bending or deformation, thereby improving the reliability and stability of the spindle.

[0006] In order to achieve the above object, the present invention provides a system for monitoring the working state of a central injection direct-connected spindle, comprising: A pull rod, a mandrel and a sleeve are coaxially arranged in sequence from the inside to the outside; a clamping assembly is arranged at one end of the mandrel to contact the pull rod and to clamp the tool; an air jet channel is arranged inside the pull rod from one end to the other end; A pre-tightening assembly includes a spring and a contact bead, the pre-tightening assembly is arranged at one end of the mandrel close to the clamping assembly, and the contact bead faces the interior of the mandrel; The fixed barrel has a through accommodating space inside, and one end is sleeved on the sleeve; the end surface of the fixed barrel away from the core shaft is provided with a plurality of grooves along the length direction, and a pressure sensor is arranged in the groove; The clamp barrel is arranged in the accommodating space and extends into the core shaft, and the outer wall of the clamp barrel abuts against the contact bead; the clamp barrel has a through space from one end face to the other end face; A ball head is fixedly arranged at one end of the clamp barrel away from the core shaft; A ball seat is fixedly connected to an end of the fixed barrel away from the core shaft and is rotatably connected to the ball head; A through hole is provided at the center of the ball head and the center of the ball seat; The pressing plate is installed at one end of the fixed barrel away from the core shaft and is fixedly connected to the clamping barrel through a fixing rod passing through the accommodating space; a hole is opened in the center of the pressing plate; and the pressing plate contacts a pressure sensor.

[0007] Furthermore, a rotatable air guide plate is arranged in the through space of the clamp barrel; the air guide plate is provided with a plurality of spaced through holes extending from one end surface to the other end surface; the farther the through hole is from the axis of the clamp barrel, the greater the angle between the axis of the through hole and the axis of the clamp barrel.

[0008] Furthermore, it also includes a limit rod, which passes through the fixed barrel and the clamping barrel, and is connected to the air guide plate; the air guide plate rotates around the straight line where the limit rod is located, and drives the limit rod to rotate; an observation bar is set at one end of the limit rod away from the air guide plate, and the observation bar rotates around the limit rod as the limit rod rotates.

[0009] Furthermore, it includes a locking assembly, which is sleeved on the fixed barrel and close to one end of the sleeve, passing through the fixed barrel and contacting the sleeve; the locking assembly is used to fix the fixed barrel on the sleeve and fix the pressure plate relative to the fixed barrel.

[0010] Furthermore, the locking assembly includes a first shell, a clamp and a first end cover; the contour of the first shell corresponds to the outer wall of the fixed barrel close to the core shaft, and the first end cover is fixedly connected to the fixed barrel; a first thread groove is opened on the inner wall of the first shell; one end of the clamp engages with the first thread groove, and the other end passes through the fixed barrel and contacts with the sleeve.

[0011] Furthermore, an anti-slip groove is provided at one end of the clamping claw contacting the sleeve.

[0012] Furthermore, the locking assembly includes a second shell, a limit block and a second end cover; the contour of the second shell corresponds to the outer wall of the fixed barrel away from the core shaft, and the second end cover is fixedly connected to the end face of the fixed barrel away from the core shaft; a second thread groove is opened on the inner wall of the second shell; the limit block is arranged corresponding to the pressure sensor and engages with the second thread groove.

[0013] Furthermore, a long groove is extended along the length direction of the inner wall of the fixed barrel toward the direction of the pressure plate; a hole is opened at the center of the end surface of the second shell close to the pressure plate, and an avoidance hole connected to the center of the second shell is opened at the position corresponding to the long groove.

[0014] Furthermore, the fixed barrel is stepped, and the farther away from the core shaft, the smaller the diameter of the fixed barrel; a fixed block extends from the inner wall of the fixed barrel toward the axis of the fixed barrel, and the fixed block contacts the end of the ball seat away from the core shaft. The contour of the fixed block fits with the end face of the ball seat to fix the ball seat.

[0015] The present invention also provides a method for monitoring the working state of a central injection direct-connected spindle, comprising the following steps: S10: Rotate the housing to fix the pressing plate relative to the fixed barrel; put the fixed barrel on the sleeve, and extend the clamping barrel into the core shaft so that the clamping barrel is pressed by the pre-tightening assembly; S20: Rotate the housing so that the clamping claws clamp the sleeve and fix the fixed barrel on the sleeve; spray air into the pull rod; S30: Control the main shaft to rotate, read the value P of each pressure sensor; detect the rotation amplitude of the observation bar; If the maximum fluctuation △P of the pressure sensor reading is within the set range, and the rotation amplitude of the observation bar is within the set range, the spindle is normal; If the maximum fluctuation △P of the pressure sensor reading exceeds the set range, and the rotation amplitude of the observation bar is within the set range, the monitoring system is abnormal and needs to be checked; If the maximum fluctuation △P of the pressure sensor reading exceeds the set range, and the rotation amplitude of the observation bar exceeds the set range, the spindle is abnormal and needs to be checked.

[0016] The beneficial effects of the present invention are as follows: by designing a system and method for monitoring the working status of a center-spray direct-connected spindle, the monitoring of whether the core shaft inside the spindle is bent or deformed is converted into a method of triggering a pressure sensor with a pressure plate, so as to better observe whether the spindle is bent; in order to prevent the problem of the monitoring system itself, the state of the pull rod is judged by whether the air guide plate drives the observation bar to rotate, intuitively prompting the operator that the pull rod may have a problem of bending or deformation; the combination of these two methods can more accurately determine whether the spindle is abnormal, and help maintenance personnel to perform maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the structure of the preload assembly on the direct-connected main shaft in the present invention; Figure 2 It is a structural schematic diagram of the central injection direct-connected spindle working state monitoring system of the present invention installed on the spindle; Figure 3 It is a front cross-sectional schematic diagram of the working state monitoring system of the central injection direct-connected main shaft in the present invention; Figure 4 It is a left view schematic diagram of the central injection direct-connected spindle working state monitoring system of the present invention after the pressure plate is removed; Figure 5It is a structural schematic diagram of the clamp barrel and the pressing plate in the central spray direct-connected spindle working state monitoring system of the present invention; Figure 6 It is a structural schematic diagram of the locking assembly of the central injection direct-connected spindle working state monitoring system in the present invention; Figure 7 It is a schematic diagram of the disassembly of the components of the locking assembly of the central injection direct-connected spindle working state monitoring system of the present invention; Figure 8 It is a monitoring principle diagram of the working state monitoring system of the central injection direct-connected spindle in the present invention when the spindle is in normal condition; Fig. 9 It is a monitoring principle diagram of the central injection direct-connected spindle working state monitoring system in the present invention when the spindle is bent; Figure numerals: 1. preload assembly; 11. spring; 12. contact bead; 2. fixed barrel; 21. accommodating space; 22. groove; 23. pressure sensor; 24. long groove; 25. fixed block; 3. clamping barrel; 31. through space; 32. air guide plate; 33. through hole; 4. ball head; 5. ball seat; 6. pressure plate; 61. fixing rod; 7. limiting rod; 71. observation strip; 8. locking assembly; 81. first shell; 82. clamping claw, 821. anti-slip groove; 83. first end cover; 84. second shell; 841. avoidance hole; 85. limiting block; 86. second end cover. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0020] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by “center”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “inside” and “outside”, etc., are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] A system for monitoring the working status of a central injection direct-connected spindle, such as Figures 1 to 7 As shown, including: The basic structure of the central jet direct-connected spindle includes a pull rod, a core shaft and a sleeve coaxially arranged from the inside to the outside; a clamping assembly is arranged at one end of the core shaft to contact the pull rod for clamping the tool; an air jet channel is arranged in the pull rod from one end to the other end; The pre-tightening assembly 1 includes a spring 11 and a contact bead 12. The pre-tightening assembly 1 is arranged at one end of the mandrel close to the clamping assembly, and the contact bead 12 faces the inside of the mandrel. An adjusting screw can also be arranged in the pre-tightening assembly 1. By rotating the adjusting screw, the compression degree of the spring 11 can be increased or decreased, thereby changing the magnitude of the pre-tightening force. This ensures that the clamp barrel 3 will not fall off when the main shaft rotates. The fixed barrel 2 has a through accommodating space 21 inside, one end of which is sleeved on the sleeve and is used to fix the entire monitoring system; the end surface of the fixed barrel 2 away from the core shaft is provided with a plurality of grooves 22 along the length direction, and a pressure sensor 23 is arranged in the groove 22; The clamp barrel 3 is arranged in the accommodating space 21 and extends into the core shaft. The outer wall of the clamp barrel 3 abuts against the contact bead 12, which ensures that the clamp barrel 3 will not fall off and will not limit the clamp barrel 3 from rotating with the main shaft. The clamp barrel 3 has a through space 31 from one end face to the other end face. The ball head 4 is fixedly arranged at one end of the clamp barrel 3 away from the core shaft; The ball seat 5 is fixedly connected to the end of the fixed barrel 2 away from the core shaft, and is rotatably connected to the ball head 4; The center of the ball head 4 and the center of the ball seat 5 are both provided with through holes; The pressure plate 6 is installed at the end of the fixed barrel 2 away from the core shaft, and is fixedly connected to the clamping barrel 3 through the fixing rod 61 passing through the accommodating space 21; the center of the pressure plate 6 is opened; the pressure plate 6 contacts the pressure sensor 23, and when the pressure plate 6 shows a tendency to shake, the pressure plate 6 will trigger the pressure sensor 23 and display the reading.

[0023] The working principle of this monitoring system is as follows: The preload assembly 1 is always installed on the mandrel. When the direct-connected spindle is working, Figure 1 As shown, the pre-tightening component 1 is responsible for assisting in fixing the tool; and in the use of the monitoring system, the pre-tightening component 1 will Figures 8 and 9 As shown, pressure is applied to the outer side of the clamp barrel 3. After the monitoring system is installed, the mandrel of the direct-connected main shaft is rotated. If the mandrel does not bend, the pressure applied by the preload assembly 1 to the outer side of the clamp barrel 3 will be as follows: Figure 8 As shown, the various pressures F are symmetrical with each other, so that the forces on the clamp barrel 3 in all directions remain stable during the rotation of the core shaft, so that there is no tendency of skewed rotation. The pressure plate 6 connected to the clamp barrel 3 will also be relatively stable, and the pressure sensor 23 in contact with the pressure plate 6 will not produce large value fluctuations.

[0024] If the mandrel is bent, the pressure applied by the preload assembly 1 to the outside of the clamp barrel 3 will Fig. 9 As shown, the pressures F are no longer symmetrical with each other, so that the clamp barrel 3 is subjected to uneven forces in all directions during the rotation of the core shaft, which will produce a tendency to rotate crookedly. The pressure plate 6 connected to the clamp barrel 3 will also have a tendency to rotate crookedly. A part of the pressure plate 6 will produce a large pressure on the pressure sensor 23, while the other part will reduce the pressure on the pressure sensor 23. In addition, as the core shaft rotates, the position where the pre-tightening component 1 applies pressure to the outside of the clamp barrel 3 will continue to change, resulting in the crooked rotation tendency of the clamp barrel 3 and the pressure plate 6 will also continue to change, and the pressure sensor 23 will produce large value fluctuations.

[0025] Preferably, a rotatable air guide plate 32 is arranged in the through space 31 of the clamp barrel 3, and the rotation axis of the air guide plate 32 is a straight line in the diameter direction thereof; the air guide plate 32 is provided with a plurality of through holes 33 arranged at intervals from one end surface to the other end surface; the farther the through hole 33 is from the axis of the clamp barrel 3, the greater the angle between the axis of the through hole 33 and the axis of the clamp barrel 3, and the distance between the end of the through hole 33 close to the mandrel and the axis of the clamp barrel 3 is smaller than the distance between the end of the through hole 33 far from the mandrel and the axis of the clamp barrel 3; When the gas is introduced into the tie rod, it will blow to the air guide plate 32. When the tie rod is not bent, the gas blown out from the tie rod will blow directly to the center of the air guide plate 32. In this case, the air flow can smoothly pass through the through hole 33, and the air flow S passing through each part of the air guide plate 32 is relatively uniform. Figure 8 As shown, the air guide plate 32 will not be pushed to rotate; once the pull rod is bent or deformed, the air flow path will change, and the air guide plate 32 will be tilted, resulting in uneven air flow S passing through various parts of the air guide plate 32, such as Fig. 9 As shown, the air guide plate 32 will be pushed to swing, so that the bending condition of the direct-connected main shaft tie rod can be reflected by observing the swing amplitude of the air guide plate 32.

[0026] Preferably, Figure 5 As shown, it also includes a limit rod 7. Through holes with diameters much larger than that of the limit rod 7 are provided on the fixed barrel 2 and the clamping barrel 3. The limit rod 7 passes through the fixed barrel 2 and the clamping barrel 3 through these through holes, and the limit rod 7 is connected to the air guide plate 32; the air guide plate 32 rotates around the straight line where the limit rod 7 is located, and drives the limit rod 7 to rotate; an observation bar 71 is provided at the end of the limit rod 7 away from the air guide plate 32, and the observation bar 71 rotates around the limit rod 7 as the limit rod 7 rotates; since the air guide plate 32 is inside the main shaft, it is difficult to observe whether it is rotating, and it is also unclear whether there is a problem with the main shaft. Through the combination of the limit rod 7 and the observation bar 71, the movement of the air guide plate 32 is transmitted to the observation bar 71 outside the main shaft, which helps the staff to observe the state of the observation bar 71 more intuitively to determine whether there is a problem with the pull rod.

[0027] like Figure 3 As shown, it includes a locking assembly 8, which is sleeved on the fixed barrel 2 and close to one end of the sleeve, passing through the fixed barrel 2 and contacting the sleeve; the locking assembly 8 is used to fix the fixed barrel 2 on the sleeve to prevent the fixed barrel 2 from falling off when the main shaft rotates; the locking assembly 8 is also used to fix the pressure plate 6 relative to the fixed barrel 2 to avoid excessive shaking of the pressure plate 6 when the fixed barrel 2 is fixed on the sleeve, which will cause excessive pressure on the pressure sensor 23 and cause damage to it, thereby affecting the accuracy of the monitoring system.

[0028] Please refer to Figures 6 and 7 The locking assembly 8 includes a first shell 81, a clamping claw 82 and a first end cover 83; the contour of the first shell 81 corresponds to the outer wall of the fixed barrel 2 close to the core shaft, and the first end cover 83 is fixedly connected to the fixed barrel 2; a first thread groove is provided on the inner wall of the first shell 81; the clamping claw 82 includes a sliding portion and a claw head; the sliding portion slides axially along the fixed barrel 2; the claw head is slidably connected to the sliding portion and slides radially along the fixed barrel 2, and an inclined hole is provided on the outer side of the fixed barrel 2, and the distance between the end of the inclined hole close to the core shaft and the axis of the fixed barrel 2 is smaller than the distance between the end away from the core shaft and the axis of the fixed barrel 2; one end of the sliding portion of the clamping claw 82 is meshed with the first thread groove, and one end of the claw head of the clamping claw 82 passes through the inclined hole of the fixed barrel 2 and contacts the sleeve; This design ensures that the first shell 81 will be restricted by the first end cover 83 and will not slip out of the fixed barrel 2; and by rotating the first shell 81, the clamp 82 can be moved as a whole in the direction close to the sleeve, so that the claw head of the clamp 82 extends toward the sleeve to clamp the sleeve, thereby fixing the fixed barrel 2 on the sleeve, thereby improving the stability of the entire monitoring system and effectively improving the accuracy of monitoring.

[0029] Preferably, an anti-skid groove 821 is provided at one end of the claw head of the clamp 82 that contacts the sleeve; the anti-skid groove 821 increases the friction between the clamp 82 and the surface of the sleeve, ensuring that the clamp 82 firmly grasps the sleeve and prevents relative sliding between the two, thereby ensuring the stability and reliability of the monitoring system; avoiding wear on the sleeve surface due to excessive local pressure, extending the service life of the sleeve and the clamp 82, and reducing maintenance costs; the claw of the clamp 82 and the support arm can also be designed as a snap-on connection, which can be installed and disassembled without tools. When targeting different spindles or other situations, clamps 82 of different specifications and sizes can be used to work better.

[0030] Please refer to Figures 6 and 7The locking assembly 8 includes a second shell 84, a limit block 85 and a second end cover 86; the contour of the second shell 84 corresponds to the outer wall of the fixed barrel 2 away from the core shaft, and the second end cover 86 is fixedly connected to the end face of the fixed barrel 2 away from the core shaft; a second threaded groove is provided on the inner wall of the second shell 84; the limit block 85 is arranged corresponding to the pressure sensor 23 and engages with the second threaded groove; the second end cover 86 limits the possibility of the second shell 84 sliding out of the fixed barrel 2; the limit block 85 can be moved by rotating the second shell 84, so that the limit block 85 is close to or away from the pressure plate 6. When installing the fixed barrel 2, the limit block 85 needs to be moved to support the pressure plate 6 to prevent the pressure plate 6 from shaking during the installation process.

[0031] like Figure 4 As shown, a long groove 24 extends from the inner wall of the fixed barrel 2 along the length direction toward the pressure plate 6, and the long groove 24 is preferably designed to be evenly distributed around the axis, so that the fixing rods 61 are arranged one by one in the long groove 24; the second shell 84 is opened at the center of the end face close to the pressure plate 6, and an avoidance hole 841 connected to the center of the second shell 84 is opened at the position corresponding to the long groove 24.

[0032] like Figure 3 As shown, the fixed barrel 2 is stepped, and the farther away from the core shaft, the smaller the diameter of the fixed barrel 2; such a design effectively reduces the overall volume and shifts the center of gravity of the monitoring system to make it closer to the end of the main shaft, thereby increasing the stability of the monitoring system during operation and reducing the error in judging the state of the main shaft; a fixed block 25 is extended from the inner wall of the fixed barrel 2 toward the axis of the fixed barrel 2, and the fixed block 25 contacts the end of the ball seat 5 away from the core shaft. The contour of the fixed block 25 fits with the end face of the ball seat 5 and is used to fix the ball seat 5. Extending the fixed block 25 from the fixed barrel 2 will not produce an additional complex structure and will not affect the movement of the fixed rod 61; and the fixed block 25 fixes the ball seat 5 from the circumference of the ball seat 5, making the pressure distribution of the ball head 4 on the ball seat 5 more uniform, avoiding displacement or loosening caused by vibration or impact, thereby ensuring the reliability of the rotational connection between the ball head 4 and the ball seat 5.

[0033] The present invention also provides a method for monitoring the working state of a central injection direct-connected spindle, comprising the following steps: S10: Rotate the housing to fix the pressing plate 6 relative to the fixed barrel 2 to prevent the pressing plate 6 from shaking; put the fixed barrel 2 on the sleeve, extend the clamping barrel 3 into the core shaft, adjust the adjusting screw in the preload assembly 1, so that the clamping barrel 3 is pressed by the contact bead 12, and fix the clamping barrel 3; S20: Rotate the housing so that the clamping claw 82 clamps the sleeve and fixes the fixed barrel 2 on the sleeve; spray air into the pull rod; S30: Control the spindle to start. When the spindle starts, its core shaft and pull rod will rotate. During the rotation process, the value P of each pressure sensor 23 is read; the rotation amplitude of the observation bar 71 is detected; The maximum fluctuation value (i.e., the difference between the maximum value and the minimum value of the pressure sensor 23) among all the fluctuation values ​​P of the pressure sensor 23 is recorded as the maximum fluctuation value ΔP; If the maximum fluctuation △P of the reading of the pressure sensor 23 is within the set range, it means that the detected bending degree of the mandrel is within the acceptable range; and the rotation amplitude of the observation bar 71 is within the set range, it means that the detected bending degree of the pull rod is within the acceptable range; at this time, the bending degree of the mandrel and the pull rod is not beyond the limit, and the main shaft is normal; If the maximum fluctuation △P of the reading of the pressure sensor 23 exceeds the set interval, it means that the detected bending degree of the mandrel exceeds the limit; and the rotation amplitude of the observation bar 71 is within the set interval, it means that the detected bending degree of the pull rod is within the acceptable range; because the mandrel and the pull rod of the direct-connected main shaft are almost in close contact, they usually bend together, then at this time it may be that the monitoring system is abnormal, for example, the clamp barrel 3 is skewed or deformed during installation, and the monitoring system needs to be checked. If the inspection result of the monitoring system is good, then retest; If the maximum fluctuation △P of the pressure sensor 23 reading exceeds the set range, it means that the detected bending degree of the core shaft exceeds the limit; and the rotation amplitude of the observation bar 71 exceeds the set range, it means that the detected bending degree of the pull rod exceeds the limit; if both detection structures are abnormal, it means that the main shaft is abnormal and the main shaft needs to be checked.

[0034] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A central injection direct-connected spindle working status monitoring system, characterized in that: include: A pull rod, a mandrel and a sleeve are coaxially arranged in sequence from the inside to the outside; a clamping assembly is arranged at one end of the mandrel to contact the pull rod and to clamp the tool; An air jet channel is provided in the pull rod from one end to the other end; A pre-tightening assembly (1) comprising a spring (11) and a contact bead (12), wherein the pre-tightening assembly (1) is arranged at one end of the mandrel close to the clamping assembly, and the contact bead (12) faces the interior of the mandrel; A fixed barrel (2) has a through accommodating space (21) inside, and one end is sleeved on the sleeve; an end surface of the fixed barrel (2) away from the core shaft is provided with a plurality of grooves (22) along the length direction, and a pressure sensor (23) is arranged in the groove (22); A clamp barrel (3) is arranged in the accommodating space (21) and extends into the core shaft, and the outer wall of the clamp barrel (3) abuts against the contact bead (12); the clamp barrel (3) has a through space (31) from one end surface to the other end surface; A ball head (4) is fixedly arranged at an end of the clamp barrel (3) away from the core shaft; A ball seat (5) is fixedly connected to an end of the fixed barrel (2) away from the core shaft, and is rotatably connected to the ball head (4); A through hole is formed at the center of the ball head (4) and the center of the ball seat (5); A pressure plate (6) is installed at one end of the fixed barrel (2) away from the core shaft and is fixedly connected to the clamping barrel (3) through a fixing rod (61) passing through the accommodating space (21); a hole is opened in the center of the pressure plate (6); and the pressure plate (6) contacts the pressure sensor (23).

2. The central injection direct-connected spindle working status monitoring system according to claim 1 is characterized in that: A rotatable air guide plate (32) is arranged in the through space (31) of the clamp barrel (3); the air guide plate (32) is provided with a plurality of through holes (33) arranged at intervals and extending from one end surface to the other end surface; the farther the through hole (33) is from the axis of the clamp barrel (3), the greater the angle between the axis of the through hole (33) and the axis of the clamp barrel (3).

3. The central injection direct-connected spindle working status monitoring system according to claim 2 is characterized in that: The invention also comprises a limiting rod (7), wherein the limiting rod (7) passes through the fixed barrel (2) and the clamping barrel (3), and the limiting rod (7) is connected to the air guide plate (32); the air guide plate (32) rotates around the straight line where the limiting rod (7) is located, and drives the limiting rod (7) to rotate; an observation strip (71) is arranged at one end of the limiting rod (7) away from the air guide plate (32), and the observation strip (71) rotates around the limiting rod (7) as the limiting rod (7) rotates.

4. The central injection direct-connected spindle working status monitoring system according to claim 1 is characterized in that: It comprises a locking assembly (8), which is sleeved on the fixed barrel (2) and close to one end of the sleeve, passes through the fixed barrel (2) and contacts the sleeve; the locking assembly (8) is used to fix the fixed barrel (2) on the sleeve and fix the pressure plate (6) relative to the fixed barrel (2).

5. The central injection direct-connected spindle working status monitoring system according to claim 4 is characterized in that: The locking assembly (8) comprises a first shell (81), a clamping claw (82) and a first end cover (83); the contour of the first shell (81) corresponds to the outer wall of the fixed barrel (2) close to the core shaft, and the first end cover (83) is fixedly connected to the fixed barrel (2); a first thread groove is provided on the inner wall of the first shell (81); one end of the clamping claw (82) is engaged with the first thread groove, and the other end passes through the fixed barrel (2) and contacts with the sleeve.

6. The central injection direct-connected spindle working status monitoring system according to claim 5 is characterized in that: An anti-slip groove (821) is formed at one end of the clamping claw (82) contacting the sleeve.

7. The central injection direct-connected spindle working status monitoring system according to claim 4 is characterized in that: The locking assembly (8) comprises a second outer shell (84), a limit block (85) and a second end cover (86); the contour of the second outer shell (84) corresponds to the outer wall of the fixed barrel (2) away from the core shaft, and the second end cover (86) is fixedly connected to the end face of the fixed barrel (2) away from the core shaft; a second thread groove is provided on the inner wall of the second outer shell (84); the limit block (85) is arranged corresponding to the pressure sensor (23) and meshes with the second thread groove.

8. The central injection direct-connected spindle working status monitoring system according to claim 7 is characterized in that: The inner wall of the fixed barrel (2) extends a long groove (24) along the length direction toward the pressure plate (6); the second shell (84) has a hole opened at the center of the end surface close to the pressure plate (6), and an avoidance hole (841) connected to the center of the second shell (84) is opened at the position corresponding to the long groove (24).

9. The central injection direct-connected spindle working status monitoring system according to claim 1 is characterized in that: The fixing barrel (2) is in a stepped shape, and the diameter of the fixing barrel (2) decreases as it is farther from the core shaft; a fixing block (25) extends from the inner wall of the fixing barrel (2) toward the axis of the fixing barrel (2); the fixing block (25) contacts an end of the ball seat (5) away from the core shaft; the contour of the fixing block (25) matches the end face of the ball seat (5) and is used to fix the ball seat (5).

10. A method for monitoring the working status of a central injection direct-connected spindle, characterized in that: The system for monitoring the working state of the central injection direct-connected spindle as claimed in any one of claims 1 to 9 comprises the following steps: S10: rotating the housing to fix the pressing plate (6) relative to the fixed barrel (2); sleeve the fixed barrel (2) onto the sleeve, and extend the clamping barrel (3) into the interior of the core shaft, so that the clamping barrel (3) is pressed against by the pre-tightening assembly (1); S20: rotating the housing so that the clamping claw (82) clamps the sleeve and fixes the fixed barrel (2) on the sleeve; and spraying air into the pull rod; S30: Control the main shaft to rotate, read the value P of each pressure sensor (23); detect the rotation amplitude of the observation bar (71); If the maximum fluctuation ΔP of the reading of the pressure sensor (23) is within the set range, and the rotation amplitude of the observation bar (71) is within the set range, the spindle is normal; If the maximum fluctuation ΔP of the reading of the pressure sensor (23) exceeds the set range, and the rotation amplitude of the observation bar (71) is within the set range, the monitoring system is abnormal and needs to be checked; If the maximum fluctuation ΔP of the reading of the pressure sensor (23) exceeds the set range, and the rotation amplitude of the observation bar (71) exceeds the set range, the spindle is abnormal and needs to be checked.

Images