Special automatic forming machine tool for machining threads in circumferential hole of DP distribution shell

Abstract

The invention belongs to the technical field of machining, and particularly relates to an automatic forming machine tool special for machining threads in a circumferential hole of a DP distribution shell, which comprises a machine tool and a screw tap, the screw tap is used for tapping a workpiece, a fracture area is arranged in the screw tap, and when the torque of the screw tap exceeds a threshold value in the tapping process of the machine tool, the screw tap can be fractured at any position of the fracture area; the separating assembly comprises a sliding shell, and when the screw tap is fractured, a sliding block moves upwards and clamps and protects the fractured part below the screw tap; the scrap removing assembly comprises a sliding rod, and in the process that the screw tap conducts tapping on the workpiece, the sliding rod continuously conducts reciprocating motion in the screw tap; the state of the screw tap is monitored in real time through torque detection, precise fracture is conducted in a preset fracture area during overload, the clamping mechanism is immediately started to fix a broken end, an automatic scrap removing and precise cooling system is matched, damage to a workpiece is effectively prevented, safe withdrawal of a broken wire is achieved, and the machining reliability and the thread quality are remarkably improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of shell thread forming, and specifically relates to a special automatic forming machine tool for processing threads of a circumferential hole of a DP distribution shell. BACKGROUND

[0002] The DP distribution shell is a key basic part in a hydraulic system, a reduction gearbox, an engine and the like, a plurality of threaded holes are usually distributed at equal angles along a central axis on a circumferential end face of the DP distribution shell, and the threaded holes are used for realizing high-precision and high-strength connection and sealing with a cover, a flange and the like, and the key challenge of processing of the threaded holes of the circumferential hole of the DP distribution shell lies in how to realize high-precision indexing (circumferential equal division) of the plurality of hole positions and efficient and reliable drilling and tapping.

[0003] A tapping machine disclosed in CN109047952A comprises a machine box and a plurality of main body structures which are uniformly distributed on the machine box, a rotating disc device is arranged on the machine box, the rotating disc device comprises a rotating disc and a mold which is uniformly arranged in a ring shape on the rotating disc, and an inlet device, a tapping device and a discharge device are sequentially arranged on the outer side of the rotating disc along the rotating direction of the rotating disc.

[0004] The above scheme has a single structure, and if the torque borne by the tap during tapping is too large and the tap is broken, the breaking position is random, the workpiece internal thread is easily damaged, and even the machine body is damaged, and the scheme lacks a rapid response and clamping protection mechanism after breaking, leading to difficulty in taking out the broken tap and high workpiece rejection rate.

[0005] Meanwhile, the scheme also lacks effective online dynamic chip removal function, and the torque is easily increased and the tap is easily stuck due to chip blockage, and the cooling system is often not accurate enough to stably deliver cooling liquid to the cutting edge, affecting the processing quality and tool life.

[0006] In addition, the above structure stays at simple torque overrun shutdown and cannot realize automatic processing after breaking, that is, the tap continues to rotate after breaking and causes mutual wear of the breaking positions, thereby increasing the difficulty of subsequent clamping and fixing of the broken tap, and the continuous extrusion and friction of the two breaking positions also cause great obstruction to transmission of the driving unit and reduce the mechanical strength, thereby increasing the difficulty of subsequent alignment and taking out.

[0007] The broken tap part remaining in the workpiece cannot be effectively fixed and taken out, and often causes secondary damage to the machined thread in subsequent processing, and the automation degree is low.

[0008] Therefore, it is necessary to develop an automatic forming machine tool with the characteristics of cleaning, breaking surface control, clamping protection and tool withdrawal. SUMMARY

[0009] To address the above problems, this invention provides a dedicated automatic forming machine tool for machining threads on the circumferential holes of a DP distribution housing, comprising a machine tool and further comprising: A tap, located on the upper side of a machine tool, is used to tap a workpiece. It has a rotation zone, a fracture zone, and a tapping zone inside. When the torque of the tap exceeds a threshold during the tapping process, the tap breaks in the fracture zone and the rotation zone moves upward, causing the two fracture zones to separate. The separation component, located on the outside of the tap, includes a sliding shell and a slider. When the tap breaks, the sliding shell drives the tapping area to rotate in the opposite direction and retract the tap through the slider. The chip removal assembly, located below the separation assembly, includes a slide bar. During the tapping process, the slide bar reciprocates inside the tap to adjust the coolant discharge rate.

[0010] By linking the tap with a preset fracture zone, the torque detector, and the separation component, controllable fracture and immediate protection of the fractured part are achieved when the tap is overloaded, effectively preventing damage to the workpiece threads. The chip removal component continuously removes chips during processing, and the cooling system accurately delivers coolant to ensure processing quality and tool life. The separation component further adds automatic clamping and safe tool retraction functions after fracture, which can automatically lock the broken end and safely remove it after the tap breaks, greatly improving the reliability and processing efficiency of the equipment when processing high-value workpieces.

[0011] Preferred options also include: The control unit, located on the upper side of the machine tool, includes a cooling unit and a rotating unit. The rotating unit is used to drive the separation assembly to rotate and move, and the cooling unit is used to introduce coolant into the chip removal assembly. The housing is located on the lower side of the control unit and is used to protect the separation assembly and the chip removal assembly; The drive shaft, located inside the housing and extending through to the output end of the rotating part, is used to transmit the rotation and movement of the rotating part; Preferred options also include: The rotating liquid storage section is located inside the housing and is connected to the output end of the cooling section. It is divided into upper and lower parts and is used to transfer the coolant transported by the cooling section. The inlet pipe is located inside the housing, with one end connected to the rotating liquid storage part and the other end connected to multiple liquid delivery pipes for outputting coolant; A torque detector is installed on the surface of the drive shaft to detect the torque of the drive shaft in real time and transmit the signal to the control unit.

[0012] Preferably, the tap further includes: Grooves are provided on the outer surfaces of the rotating and tapping areas to cooperate with the separation and chip removal components to adjust the impurity removal rate. The rotating zone is formed on the upper part of the tap and is used to support the rotational force of the bearing separation component and drive the tap to rotate and move; the tapping zone is formed on the lower half of the tap and is used to tap the workpiece of the machine tool; the diameter of the fracture zone is smaller than that of the rotating zone and the tapping zone, and the maximum torque force it can withstand is smaller than that of the rotating zone and the tapping zone.

[0013] Preferably, the separation component further includes: The telescopic body is fixedly installed on the lower side of the drive shaft and is used to transmit the rotation of the drive shaft; The gripper is fitted on the outside of the telescopic body and is used to drive the tap to rotate. The height of the rotating area of ​​the telescopic body can be adjusted by the gripper. The sliding shell is located on the lower side of the jaws and has an arc-shaped surface and a vertical surface. When the tap breaks in the fracture zone, the telescopic body moves the jaws upward and the rotating zone upward. The rotating zone rotates in the opposite direction, which drives the tapping zone to rotate in the opposite direction through the sliding shell and the slider to retract the tap.

[0014] Preferably, the separation component further includes: The groove is set on the side wall of the sliding shell, and the slider is set inside the groove. It is used to protect the tapping area when the tap breaks in the fracture zone. At the same time, after the tap breaks in the fracture zone, the slider inside the groove drives the tapping area to reverse and retract the tool. The arc-shaped component is fixedly installed inside the housing and is used to drive the slider to reciprocate up and down during the rotation of the slider. The elastic element is set in the groove, with one end connected to the upper surface of the groove and the other end connected to the upper surface of the slider. It is used to ensure that the slider is always in contact with the arc-shaped element when the tap is tapping normally.

[0015] Preferably, the dust removal assembly further includes: The chip removal component is installed on the outer surface of the slide bar and is used to remove chips generated in the tapping area during the reciprocating motion of the slide bar. The liquid storage chamber, located inside the slider, is used for the temporary storage and discharge of coolant; the sliding rod is located on the bottom surface of the slider and moves up and down with the slider during the tapping process.

[0016] Preferably, the dust removal assembly further includes: The infusion tube is located inside the slider, with one end connected to the inlet tube and the other end extending into the storage chamber; The outlet is located inside the infusion tube, with one end connected to the inside of the infusion tube and the other end connected to the storage chamber. It is used to regulate the amount of coolant delivered from the infusion tube to the storage chamber. The drain chamber is located inside the slide bar, with one end connected to the liquid storage chamber and the other end connected to the outside. It is used to deliver coolant to the tapping area.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By linking the preset fracture zone with the torque detector, this structure achieves precise fracture control when the tap is overloaded, keeping the fracture location in a non-critical area. This not only protects the main structure of the machine tool but also creates favorable conditions for subsequent processing, significantly improving the safety and reliability of the equipment.

[0018] 2. The chip removal component, through the reciprocating motion of the slide bar, effectively avoids problems such as increased torque and tap jamming caused by chip blockage. The chip removal action, in conjunction with the chip removal action, forms a dual cleaning effect of "mechanical + fluid". This mechanism ensures the stability and continuity of the thread processing process and significantly improves the quality and consistency of thread forming.

[0019] 3. Through the coordinated design of the liquid storage chamber and multi-stage pipeline, stable delivery and precise distribution of coolant are achieved, ensuring a constant coolant flow rate; the adjustable outlet optimizes the coolant supply. This cooling system effectively reduces the cutting temperature and frictional wear between the tap and the workpiece, which not only extends the service life of the tap but also prevents changes in the microstructure of the workpiece material due to overheating, thus ensuring machining accuracy.

[0020] 4. It can quickly lock the broken part to prevent it from moving inside the workpiece and causing thread damage. It also has an automatic retraction function. By driving the reverse direction, the clamped broken wire is safely withdrawn, completely avoiding secondary damage to the workpiece caused by the traditional broken wire removal process. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a partial structural diagram of the housing of the present invention; Figure 3 This is a schematic diagram of a partial three-dimensional cross-sectional structure of the housing of the present invention; Figure 4 This is a three-dimensional structural diagram of the portion of the present invention excluding the housing; Figure 5 This is a schematic diagram of the three-dimensional structure of the tap of the present invention; Figure 6 This is a partial three-dimensional structural diagram of the separation component and the debris removal component of the present invention; Figure 7 This is a three-dimensional structural diagram of another part of the separation component and the debris removal component of the present invention; Figure 8 For the present invention Figure 7 Enlarged structural diagram at point A in the middle; Figure 9 This is a schematic diagram of the internal structure of the separation component and the chip removal component of the present invention; Figure 10For the present invention Figure 9 Enlarged structural diagram at point B; Figure 11 This is a schematic diagram of the internal cross-sectional structure of the housing of the present invention.

[0022] In the diagram: 1. Machine tool; 2. Control unit; 3. Tap; 301. Rotating area; 302. Fracture area; 303. Tapping area; 304. Groove; 4. Separation assembly; 401. Telescopic body; 402. Gripper; 403. Arc-shaped surface; 404. Sliding shell; 405. Slider; 408. Arc-shaped component; 409. Slide groove; 412. Elastic component; 5. Housing; 6. Chip removal assembly; 601. Slide rod; 604. Chip removal component; 605. Liquid outlet; 606. Liquid storage chamber; 607. Infusion pipe; 611. Drainage chamber; 7. Drive shaft; 8. Torque detector; 9. Inlet pipe; 10. Rotating liquid storage part. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1 When the existing thread machining machine tool breaks due to excessive torque of tap 3, the fracture location of tap 3 is random. After tap 3 breaks, it loses torque force instantly and will collide with the thread, which can easily damage the workpiece thread or even the machine tool body. At the same time, it lacks an effective online dynamic chip removal function, which can easily lead to increased torque and jamming of tap 3 due to chip blockage. The cooling system is often not precise enough and it is difficult to stably deliver coolant to the cutting edge, which affects the machining quality and tool life.

[0025] like Figures 1 to 11As shown, this invention designs a dedicated automatic forming machine tool for machining threads in the circumferential holes of a DP distribution shell, addressing the shortcomings of traditional machine tools. The tool includes: a machine tool 1 for carrying the workpiece to be processed; and a tap 3, positioned on the upper side of the machine tool 1 for tapping the workpiece. The tap 3, internally configured with a rotation zone 301, a fracture zone 302, and a tapping zone 303, causes the tap 3 to break in the fracture zone 302 when the torque exceeds a threshold during tapping. The rotation zone 301 then moves upward, causing the two fracture zones 302 to separate. The diameter of the fracture zone 302 is precisely machined to be smaller than the adjacent rotation zone 301 and tapping zone 303, minimizing its cross-sectional modulus and making it the weakest mechanical link in the entire force transmission path. When the torque of the tap 3 exceeds the threshold during tapping, the tap 3 will break at any position in the fracture zone 302.

[0026] The separation component 4, located on the outside of the tap 3, includes a sliding shell 404 and a slider 405. When the tap 3 breaks, the sliding shell 404 drives the tapping area 303 to rotate in the opposite direction and retract the tool through the slider 405, preventing irreversible damage to the thread caused by the instantaneous disappearance of torque force in the broken part. The chip removal component 6, located on the lower side of the separation component 4, includes a slide rod 601. During the tapping process of the tap 3, the slide rod 601 reciprocates inside the tap 3 to adjust the coolant discharge, preventing excessive accumulation of chips in the groove 304 of the tap 3, which would cause excessive torque on the tapping area 303 and lead to breakage.

[0027] It also includes: a control unit 2, which is located on the upper side of the machine tool 1 and includes a cooling unit and a rotating unit. The rotating unit is used to drive the separation component 4 to rotate and move, and the cooling unit is used to introduce coolant into the chip removal component 6; a housing 5, which is fixedly located on the lower side of the control unit 2 and is used to protect the separation component 4 and the chip removal component 6; and a drive shaft 7, which is located inside the housing 5 and extends through to the output end of the rotating unit, and is used to transmit the rotation and movement of the rotating unit, thereby driving the separation component 4 and the chip removal component 6 to rotate and move.

[0028] The rotating liquid storage section 10 is located inside the housing 5 and is connected to the output end of the cooling section. It is divided into upper and lower parts and is used to transfer the coolant transported by the cooling section. The liquid inlet pipe 9 is located inside the housing 5. One end is connected to the rotating liquid storage section 10 and the other end is connected to multiple liquid delivery pipes 607 for outputting coolant. The torque detector 8 is located on the surface of the drive shaft 7 and is used to detect the torque of the drive shaft 7 in real time and transmit the signal to the control section 2. The control section 2 makes corresponding actions based on the signal from the torque detector 8.

[0029] The tap 3 also includes: a groove 304, which is disposed on the outer surface of the rotating area 301 and the tapping area 303, for cooperating with the separation component 4 and the chip removal component 6 to adjust the impurity removal rate; the rotating area 301 is formed in the upper part of the tap 3, for supporting the rotational force of the separation component 4 and driving the tap 3 to rotate and move; the tapping area 303 is formed in the lower half of the tap 3, for tapping the workpiece of the machine tool 1; the diameter of the fracture area 302 is smaller than that of the rotating area 301 and the tapping area 303, and the maximum torque force it can withstand is smaller than that of the rotating area 301 and the tapping area 303.

[0030] When the instantaneous overload torque exceeds the yield limit of the material in the fracture zone 302 and reaches the fracture strength, the stress concentration effect makes the fracture zone 302 an inevitable fracture location. The tap 3 will undergo instantaneous brittle fracture or high-cycle fatigue fracture at any cross-section in this region. Thus, the tap 3 is separated into two parts: the upper part is the rotation zone 301 and the fracture zone 302, and the lower part is the tapping zone 303 remaining in the threaded hole of the workpiece and the partially fractured fracture zone 302.

[0031] The separation assembly 4 also includes: a telescopic body 401, fixedly mounted on the lower end of the drive shaft 7, used to transmit the rotation of the drive shaft 7; the telescopic body 401 can be an electric push rod structure; a gripper 402, sleeved on the outside of the telescopic body 401, used to drive the tap 3 to rotate; and a sliding shell 404, slidably mounted on the lower side of the gripper 402, having an arc-shaped surface 403 and a vertical surface thereon. When the tap 3 breaks in the fracture zone 302, the gripper 402 moves upward along the telescopic body 401 and drives the rotation zone 301 to move upward, rotating... The reverse rotation of zone 301 drives the tapping zone 303 to rotate in the opposite direction via the sliding shell 404 and the slider 405 to retract the tool. This prevents the tapping zone 303 from being damaged by the continued rotation of the rotating zone 301 after the tap 3 breaks. Meanwhile, the chuck 402 continues to rotate on the arc surface 403. The chuck 402 drives the rotating zone 301 to move upward and rotate, so that the distance difference between the rotating zone 301 and the tapping zone 303 is greater than the height of the fracture zone 302. This prevents the two fracture surfaces of the fracture zone 302 from colliding and damaging the workpiece.

[0032] The separation component 4 also includes: a slide groove 409, disposed on the side wall of the sliding shell 404; a slider 405 disposed inside the slide groove 409, slidingly connected to the sliding shell 404, and slidingly connected to the groove 304 on the tapping area 303, which drives the slider 405 to rotate when the tapping area 303 rotates, thus protecting the tapping area 303 when the tap 3 breaks, and also driving the tapping area 303 to reverse and retract after the tap 3 breaks; an arc-shaped member 408, fixedly disposed inside the shell 5, which drives the slider 405 to reciprocate up and down during the rotation of the slider 405; and an elastic member 412, disposed inside the slide groove 409, with one end connected to the upper surface of the slide groove 409 and the other end connected to the upper surface of the slider 405, ensuring that the slider 405 is always in contact with the arc-shaped member 408 during the reciprocating up and down movement of the slider 405.

[0033] The chip removal assembly 6 also includes: a chip removal component 604, which is disposed on the outer surface of the slide bar 601, and is used to remove the chips generated in the tapping area 303 during the reciprocating motion of the slide bar 601, to prevent the chips from being too long and difficult to clean, thus wrapping around the surface of the tapping area 303 and causing an increase in the torque of the tap 3; a liquid storage chamber 606, which is disposed inside the slider 405, and is used for the temporary storage and discharge of coolant; the slide bar 601 is disposed on the bottom surface of the slider 405, and moves up and down with the slider 405 during the tapping process of the tap 3.

[0034] The chip removal assembly 6 also includes: a liquid delivery pipe 607, located inside the slider 405, with one end connected to the liquid inlet pipe 9 and the other end extending into the liquid storage chamber 606; a liquid outlet 605, located inside the liquid delivery pipe 607, with one end connected to the inside of the liquid delivery pipe 607 and the other end connected to the liquid storage chamber 606, used to adjust the amount of coolant delivered by the liquid delivery pipe 607 to the liquid storage chamber 606 so that the discharge volume of the drain chamber 611 changes; and a drain chamber 611, located inside the slide rod 601, with one end connected to the liquid storage chamber 606 and the other end connected to the outside, used to deliver coolant to the tapping area of ​​the tap 3. During the tapping process in the tapping area 303, the height of the drain chamber 611 changes continuously, and the discharge volume changes continuously, thereby performing pulse cleaning and cooling on the tapping area 303, while simultaneously carrying the chips out of the groove 304.

[0035] When using the machine tool, the operator must first perform a series of preparatory work, including checking whether each part of the machine tool 1 is complete and whether the connection is firm, especially checking whether the tap 3 is intact and whether there is any pre-damage in the fracture zone 302. The DP distribution shell workpiece to be processed is firmly clamped on the worktable of the machine tool 1 to ensure its accurate position. The axis of the circumferential hole to be processed is aligned with the expected movement axis of the tap 3, and the jaws 402 and the grooves 304 on the outer surface of the rotating area 301 are engaged to prevent the tap 3 from being damaged by the machine tool 1 due to improper installation during the tapping process. The operator needs to input the processing parameters on the operation interface of the control unit 2. These parameters mainly include the rotation speed of the tap 3, the moving speed, and the maximum torque that the fracture zone 302 in the tap 3 can withstand.

[0036] When the tapping program is started, the rotating part of the control unit 2 begins to work. The rotating part transmits the rotational motion and downward movement to the telescopic body 401 through the drive shaft 7. The telescopic body 401 rotates and moves, causing the gripper 402 to rotate and move downward. The outer surface of the gripper 402 engages with the groove 304 on the outer surface of the rotating area 301. The rotation of the gripper 402 causes the rotating area 301 of the tap 3 to rotate and move downward, thereby causing the fracture area 302 and the tapping area 303 to rotate and move downward. The downward movement of the gripper 402 causes the sliding shell 404 to move downward. Since the groove 304 on the tapping area 303 is slidably connected to the slider 405, the rotation of the tapping area 303 causes the slider 405 to rotate. The rotation of the slider 405 causes the sliding shell 404 to rotate, so that the sliding shell 404 and the gripper 402 rotate synchronously, and the height of the shell 5 remains unchanged.

[0037] As the drive shaft 7 moves downward and rotates, the cooling unit works accordingly, supplying coolant to the liquid storage chamber 606 inside the slider 405 through the rotation of the liquid storage section 10 and the liquid inlet pipe 9. As the tapping area 303 of the tap 3 begins to rotate and moves downward according to the preset feed rate, the tapping process officially begins. The tapping area 303 gradually contacts and cuts into the circumferential hole of the DP distribution shell. At the moment of cutting, the resistance increases, and the torque on the drive shaft 7 will have a significant increase. The torque detector 8 continuously transmits this torque signal back to the control unit of the control unit 2 in real time. The control unit compares the real-time torque value with the preset threshold. As long as the real-time value is lower than the threshold, the machining will continue.

[0038] When tapping, the chips inside the tap 3 need to be removed in time, otherwise they will clog the groove 304, causing the torque of the tap 3 to increase sharply or even causing the tap 3 to jam and break. Therefore, the chips in the groove 304 need to be cleaned in time.

[0039] During the cutting process of tap 3, the lower surface of slider 405 is always in contact with arc-shaped component 408 under the action of elastic component 412. Since arc-shaped component 408 is fixed on the inner wall of housing 5 and has a certain angle, slider 405 will reciprocate within the slide groove 409 due to the action of arc-shaped component 408 during rotation. The reciprocating motion of slider 405 drives slide rod 601 to reciprocate. During the reciprocating motion of slide rod 601, coolant in liquid storage chamber 606 is discharged through drain chamber 611. As the height of the lower outlet of the drain chamber 611 changes continuously, the overlapping area of ​​the outlet 605 and the storage chamber 606 changes continuously as the slider 405 moves up and down. This changes the amount of coolant entering the drain chamber 611 from the storage chamber 606, resulting in a continuous change in the amount of coolant discharged downward from the drain chamber 611. This not only cools the threaded area of ​​the tapping area 303 but also removes the chips generated during threading with pulses, allowing the chips to be smoothly flushed away by the coolant.

[0040] During the thread machining process as the tapping zone 303 continuously rotates downwards, if the value detected by the torque detector 8 increases but does not reach the set threshold, it indicates that the workpiece material is too hard or there is internal cutting blockage. Therefore, the downward force applied by the telescopic body 401 to the gripper 402 increases. Since the gripper 402 is engaged with the rotating zone 301, the downward pressure applied by the gripper 402 to the tapping zone 303 through the rotating zone 301 and the fracture zone 302 increases, thereby increasing the cutting force of the tapping zone 303 on the workpiece. When the gripper 402 moves downwards, it drives the sliding shell 404 and the infusion tube 607 to move downwards. However, because the height of the slider 405 is limited by the arc-shaped part 408, it cannot follow the infusion tube. As the liquid pipe 607 moves downwards synchronously, the length of the liquid pipe 607 inserted into the liquid storage cavity 606 increases, the opening area of ​​the liquid outlet 605 increases, and the amount of coolant entering the liquid storage cavity 606 through the liquid outlet 605 increases. Ultimately, more coolant is discharged through the drain cavity 611. This, combined with the up-and-down movement of the slider 405, achieves pulsed drainage of the drain cavity 611, further improving the cooling and flushing effect on the processing position and preventing it from jamming and affecting normal use. Afterwards, when the torque value detected by the torque detector 8 decreases to its initial value, the amount of coolant introduced into the liquid storage cavity 606 by rotating the liquid storage part 10 and the liquid inlet pipe 9 is restored to its initial value, and the normal operation can continue according to the above process.

[0041] When abnormal resistance suddenly occurs, the value monitored by the torque detector 8 rises rapidly and transmits a signal to the control unit 2. The control unit 2 controls the rotating part and the cooling part to stop working, and the torque of the tap 3 exceeds its maximum value and breaks. Since the diameter of the fracture zone 302 is deliberately designed to be smaller than that of the rotating zone 301 and the tapping zone 303, its mechanical strength is also the weakest. When the torque exceeds its designed fracture threshold, the stress concentration effect makes the fracture zone 302 the weakest link. The tap 3 will break instantly at any position in the fracture zone 302. Thus, the tap 3 is divided into two parts: the upper part is the rotating zone 301 that is still held by the separation component 4, and the lower part is the tapping zone 303 that remains in the workpiece hole.

[0042] When the value monitored by the torque detector 8 rises and exceeds the set threshold, then suddenly decreases to the minimum value, it indicates that the fracture zone 302 has fractured. The control unit 2 controls the cooling unit to stop supplying coolant downwards, and at the same time, the telescopic body 401 stops feeding downwards to prevent the rotating area 301 on the tap 3 from continuing to transmit downward feed force to the tapping area 303, thus avoiding secondary damage to the tap 3. Meanwhile, the jaw 402 continues to rotate under the action of inertia. Since the arc surface 403 has a certain slope, the lower surface of the jaw 402 has the same slope as the arc surface 403, so that the jaw 402 continues to rotate on the arc surface 403 without driving the sliding shell 404 and the tapping area 303 of the tap 3 to rotate.

[0043] At this point, the operator should notify the staff to intervene. The operator needs to carefully release the clamping state of the separation component 4. Then, the operator can use a special tool, such as a broken wire extractor, to carefully remove the broken part of the tap 3 inside the workpiece. After that, check the damage to the threaded hole of the workpiece. If the damage is minor, the machining can continue after replacing the tap 3. If the damage is serious, the hole needs to be repaired. At the same time, the operator needs to check whether the components of the separation component 4 and the chip removal component 6 are damaged, clean up any chips and coolant residue, and replace the tap 3 of the machine tool 1 with a brand new one that also has a preset fracture zone 302. After confirming that all components are intact and installed correctly, the machine tool 1 can be restarted to start from the interrupted step or start a new machining cycle from the beginning.

[0044] Example 2 While the above structure solves the problem of uncertain tap 3 fracture location, the rotating area 301 will continue to rotate at a certain angle due to inertia after fracture, causing the two fracture surfaces of the fracture area 302 to rub and collide with each other, thereby increasing the difficulty of clamping and fixing the tapping area 303. Furthermore, the continuous squeezing and friction between the two fracture surfaces will also cause great resistance to the transmission of the drive shaft 7 and reduce mechanical strength. At the same time, the tapping area 303 will collide with the circumferential hole due to the sudden loss of rotational force, which will cause irreversible damage to the tap 3 and the already machined threads in the circumferential hole. In addition, the tap 3 that has broken in the circumferential hole is not easy to retract, which is fatal for large and expensive workpieces. Therefore, based on the first embodiment, the present invention designs the following structure, including: The vertical surface on the sliding shell 404 allows the jaws 402 to move upward along the telescopic body 401 after the tap 3 breaks in the fracture zone 302, thus moving the rotating zone 301 upward as well. This ensures that the distance difference between the rotating zone 301 and the tapping zone 303 is greater than the height of the fracture zone 302, preventing the two fracture surfaces of the fracture zone 302 from colliding and damaging the workpiece. At the same time, the height of the jaws 402 is always lower than the highest point of the vertical surface on the sliding shell 404, which is used to drive the sliding shell 404 to reverse.

[0045] In use, when the control unit 2 drives the drive shaft 7 to move downward, the drive shaft 7 drives the telescopic body 401 and the gripper 402 to move downward. The downward movement of the gripper 402 drives the sliding shell 404 to move downward, and the height of the shell 5 remains unchanged.

[0046] When the torque detector 8 detects that the torque of the drive shaft 7 increases rapidly and exceeds the set threshold, and then suddenly decreases to the minimum value, it sends a command to the control unit 2. The control unit 2 controls the rotating part and the cooling part to stop working. After the tap 3 breaks in the fracture zone 302, since the control unit 2 controls the rotating part and the cooling part to stop working, the control unit 2 controls the telescopic body 401 to move upward. The upward movement of the telescopic body 401 drives the gripper 402 to move upward. The upward movement of the gripper 402 drives the rotating zone 301 and the upper half of the broken part to move upward and separate from the lower half of the fracture zone 302. At the same time, during the upward movement of the gripper 402, the height of the gripper 402 is always lower than the highest point of the vertical surface of the sliding shell 404.

[0047] Meanwhile, since the slider 405 and the sliding shell 404 are connected vertically, the force generated in the horizontal direction by the sudden breakage of the tap 3 in the tapping area 303 is transmitted to the slider 405. The slider 405 is limited by the groove 304 inside the tapping area 303, and the outer wall of the slider 405 is limited by the shell 5. Therefore, the slider 405 cannot wobble horizontally, thus keeping the position of the tapping area 303 of the tap 3 unchanged. This fixes the tapping area 303 inside the circumferential hole for machining the thread, preventing the tapping area 303 from moving randomly after the tap 3 breaks and damaging the already machined thread.

[0048] Subsequently, the control unit 2 can control the rotating part to control the drive shaft 7 to reverse. The drive shaft 7 rotates, causing the telescopic body 401 and the gripper 402 to reverse. The gripper 402 abuts against the vertical surface of the sliding shell 404. The rotation of the gripper 402 causes the sliding shell 404 to reverse. Since the rotating area 301 is moved upward by the gripper 402 and the distance between it and the tapping area 303 is greater than the height of the fracture area 302, the rotation of the sliding shell 404 causes the slider 405 and the tapping area 303 to reverse. The tapping area 303 is only engaged by the slider 405 for reverse transmission, so that the tapping area 303 reverses and retracts from the circumferential hole, preventing the tapping area 303 from damaging the thread. After the tap 3 retracts, the operator replaces the tap 3 with a new one and then re-machines the thread in the circumferential hole. When the thread machining is completed, the tapping is finished, and the operator can then remove the machined workpiece.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A special automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing, comprising a machine tool (1), characterized in that, Also includes: The tap (3) is set on the upper side of the machine tool (1) and is used to tap the workpiece. It has a rotating area (301), a fracture area (302) and a tapping area (303) inside. When the torque of the tap (3) exceeds the threshold during the tapping process, the tap (3) breaks in the fracture area (302) and the rotating area (301) moves upward to separate the two fracture areas (302). The separation component (4) is located on the outside of the tap (3) and includes a sliding shell (404) and a slider (405). When the tap (3) breaks, the sliding shell (404) drives the tapping area (303) to rotate in the opposite direction and retract the tool through the slider (405). The chip removal assembly (6), which is located on the lower side of the separation assembly (4), includes a slide rod (601). During the tapping process of the tap (3) on the workpiece, the slide rod (601) reciprocates inside the tap (3) to adjust the amount of coolant discharged.

2. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 1, characterized in that, Also includes: The control unit (2) is located on the upper side of the machine tool (1) and includes a cooling unit and a rotating unit. The rotating unit is used to drive the separation assembly (4) to rotate and move, and the cooling unit is used to introduce coolant into the chip removal assembly (6). The housing (5) is located on the lower side of the control unit (2) and is used to protect the separation assembly (4) and the chip removal assembly (6). The drive shaft (7) is located inside the housing (5) and extends through to the output end of the rotating part, and is used to transmit the rotation and movement of the rotating part.

3. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 2, characterized in that, Also includes: Rotary liquid storage section (10) is located inside the housing (5) and connected to the output end of the cooling section. It is divided into upper and lower parts and is used to transfer the coolant transported by the cooling section. The inlet pipe (9) is located inside the housing (5), with one end connected to the rotating liquid storage part (10) and the other end connected to multiple liquid delivery pipes (607) for outputting coolant; A torque detector (8) is installed on the surface of the drive shaft (7) to detect the torque of the drive shaft (7) in real time and transmit the signal to the control unit (2).

4. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 1, characterized in that, The tap (3) also includes: The groove (304) is provided on the outer surface of the rotating area (301) and the tapping area (303) for cooperating with the separation component (4) and the chip removal component (6) to adjust the impurity removal rate; The rotating area (301) is formed on the upper part of the tap (3) and is used to support the rotational force of the bearing separation component (4) and drive the tap (3) to rotate and move; the tapping area (303) is formed on the lower half of the tap (3) and is used to tap the workpiece of the machine tool (1); the diameter of the fracture area (302) is smaller than that of the rotating area (301) and the tapping area (303), and the maximum torque force it can withstand is smaller than that of the rotating area (301) and the tapping area (303).

5. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 4, characterized in that, The separation component (4) further includes: The telescopic body (401) is fixedly installed on the lower side of the drive shaft (7) and is used to transmit the rotation of the drive shaft (7); The gripper (402) is sleeved on the outside of the telescopic body (401) and is used to drive the tap (3) to rotate. The telescopic body (401) adjusts the height of the rotating area (301) through the gripper (402). The sliding shell (404) is slidably disposed on the lower side of the jaw (402), and has an arc-shaped surface (403) and a vertical surface. When the tap (3) breaks in the fracture zone (302), the telescopic body (401) drives the jaw (402) to move upward and drives the rotating zone (301) to move upward. The rotating zone (301) rotates in the opposite direction and drives the tapping zone (303) to rotate in the opposite direction through the sliding shell (404) and the slider (405) to retract the tool.

6. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 5, characterized in that, The separation component (4) further includes: A groove (409) is provided on the side wall of the sliding shell (404), and a slider (405) is provided inside the groove (409) to protect the tapping area (303) when the fracture zone (302) of the tap (3) breaks. At the same time, after the fracture zone (302) of the tap (3) breaks, the slider (405) drives the tapping area (303) to reverse and retract the tool inside the groove (409). The arc-shaped component (408) is fixedly installed inside the housing (5) and is used to drive the slider (405) to reciprocate up and down during the rotation of the slider (405); The elastic element (412) is set in the groove (409), with one end connected to the upper surface of the groove (409) and the other end connected to the upper surface of the slider (405), so that the slider (405) is always in contact with the arc-shaped element (408) when the tap (3) is tapping normally.

7. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 3, characterized in that, The chip removal assembly (6) further includes: A chip removal component (604) is provided on the outer surface of the slide bar (601) and is used to remove chips generated in the tapping area (303) during the reciprocating motion of the slide bar (601); The liquid storage chamber (606) is located inside the slider (405) and is used for the temporary storage and discharge of coolant; the slide bar (601) is located on the bottom surface of the slider (405) and moves up and down with the slider (405) during the tapping process of the tap (3).

8. The automatic forming machine tool for machining threads in the circumferential holes of a DP distribution housing according to claim 7, characterized in that, The chip removal assembly (6) further includes: An infusion tube (607) is installed inside the slider (405), with one end connected to the inlet tube (9) and the other end extending into the reservoir (606); The outlet (605) is located inside the infusion pipe (607), with one end connected to the inside of the infusion pipe (607) and the other end connected to the storage chamber (606), and is used to regulate the amount of coolant delivered from the infusion pipe (607) to the storage chamber (606); The drain chamber (611) is located inside the slide bar (601), with one end connected to the liquid storage chamber (606) and the other end connected to the outside. It is used to deliver coolant to the tapping area of ​​the tap (3).

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