A CNC group drilling machine tool

Abstract

The present invention relates to the technical field of mechanical processing equipment, and in particular discloses a CNC group drilling machine tool, including a workbench, four guide rods are arranged on the workbench, the four guide rods are provided with a lifting plate, a fixed plate and a top plate, a tooling assembly is arranged on the lifting plate, a drilling tool assembly is arranged on the upper surface of the fixed plate, a driving assembly is arranged on the top plate, the driving assembly is connected to the drilling tool assembly by transmission, a positioning assembly is arranged inside the workbench, and a control device is arranged on the top of the workbench. The present invention controls the feed amount of the workpiece through the movement of the lifting rod, the cooperation of the first detection block, the second detection block and the detection switch, and the control is precise. When drilling, the support plate supports the tooling plate, the tooling plate and the support plate are subjected to force, and the second actuator is not subjected to force, so as to avoid the damage of the second actuator due to force. After the drilling is completed, the second actuator drives the tooling plate to move, so as to ensure that the hole can be thoroughly drilled, and the drill bit verifies the hole to realize the correction of the hole axis deviation and improve the drilling quality.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing equipment, and in particular to a numerical control group drilling machine tool. Background Art

[0002] Drilling refers to the operation of using a drill bit to machine a hole in a solid material. At present, drilling is generally done on a drilling machine. Common drilling machine equipment includes desktop drilling machines, vertical drilling machines, and radial drilling machines. Most ordinary drilling machines can only process one hole at a time, but for some porous workpieces, if they are drilled one by one, it will undoubtedly increase the labor intensity, the drilling efficiency will be low, and it is easy to miss holes, which will increase the number of defective workpieces. Therefore, group drilling machines have emerged for porous workpieces. As a new type of hole processing equipment, group drilling machines are widely used in drilling operations of porous parts in the machinery industry.

[0003] A Chinese invention patent application (application publication number CN102847973A) discloses a group drilling device and a processing method using the device, including a drilling mechanism provided above a workbench; the drilling mechanism includes a driving mechanism and a plurality of power output shafts driven by the driving mechanism, each power output shaft is connected to a drill rod via a transmission mechanism, and the drill rod is connected to a drill bit or a tap; however, the technical solution realizes the feeding of the drilling hole by pushing the drill rod box through a feed cylinder, and the transmission shaft expands and contracts during the rotation process, which is prone to vibration, causing the drill bit to swing, resulting in large drilling errors, and the feed amount cannot be controlled, and the feed cannot be guaranteed, which is prone to uneven feed amount, affecting the drilling quality.

[0004] Therefore, it is necessary to propose an improvement of a CNC group drilling machine to overcome the defects of the prior art. Summary of the invention

[0005] The purpose of the present invention is to solve the problems in the prior art and provide a numerically controlled group drilling machine tool.

[0006] The technical solution of the present invention is:

[0007] A CNC group drilling machine comprises a workbench, four guide rods are arranged on the top of the workbench, the four guide rods are distributed in a matrix, a lifting plate, a fixed plate and a top plate are arranged on the four guide rods from bottom to top, the lifting plate can be lifted and lowered on the guide rods by a first actuator, a tooling assembly is arranged on the lifting plate, the fixed plate is fixedly arranged on the guide rods, a drilling tool assembly is arranged on the upper surface of the fixed plate, a top plate is fixedly arranged on the upper end of the guide rods, a driving assembly is arranged on the top plate, the driving assembly is connected to the drilling tool assembly in transmission, a positioning assembly is arranged inside the workbench, a control device is arranged on one side of the top of the workbench, and the tooling assembly, the driving assembly and the positioning assembly are electrically connected to the control device.

[0008] Preferably, the tooling assembly includes a tooling base plate, a tooling plate, a support plate and two second actuators, a guide column is provided at each of the four corners of the tooling base plate, the top of the guide column penetrates upward and is slidably mounted on the tooling plate, a plurality of avoidance holes are evenly distributed on the tooling plate, the support plate is provided on the tooling base plate and is located below the tooling plate, and the two second actuators are symmetrically provided on the tooling base plate and are located on both sides of the support plate;

[0009] When drilling, the support plate supports the tooling plate and bears the force, while the second actuator is not subjected to the force, thereby avoiding damage to the second actuator. When the hole is drilled through, the position of the drill bit is avoided through the avoidance hole to prevent the tooling plate from interfering with the drill bit and causing damage to the drill bit. After the hole is drilled through, the second actuator drives the tooling plate to move up and down, and the hole is checked by the drill bit to ensure that the hole is drilled thoroughly and the axial deviation of the hole is corrected.

[0010] Preferably, the positioning assembly includes a lifting rod and a switch bracket, the upper end of the lifting rod penetrates upward through the workbench and is connected to the lifting plate, the lifting rod is provided with a first detection block and a second detection block, the switch bracket is provided on the workbench, and three detection switches are provided at intervals on the switch bracket;

[0011] The lifting rod moves up and down with the lifting plate. During the movement, the first detection block and the second detection block trigger the detection switch respectively to judge the different lifting positions and states of the lifting plate, and through signal interaction with the control device, the control device controls the execution of different actions.

[0012] Preferably, the driving assembly includes a driving motor, a large gear shaft and a plurality of small gear shafts, the driving motor is arranged on the top plate, the large gear shaft and the plurality of small gear shafts are rotatably arranged on the top plate, the plurality of small gear shafts are evenly arranged around the large gear shaft, and are all meshed with the large gear shaft for transmission, the driving motor and the large gear shaft are in transmission connection, and the transmission mode is belt transmission, gear transmission or chain transmission;

[0013] The driving motor drives the large gear shaft to rotate, and drives several small gear shafts to rotate at high speed through meshing to provide power for the drilling tool assembly. The transmission mode is flexible and diverse, easy to implement and reliable.

[0014] Preferably, the drilling tool assembly includes a tool seat, on which a plurality of mounting holes are evenly arranged in a matrix, the mounting holes correspond to the avoidance holes one by one, a chuck is rotatably arranged in the mounting hole, the lower end of the chuck passes downward through the mounting hole and is connected to a drill bit, and the chuck is connected to the pinion shaft through a universal shaft;

[0015] By installing the chuck in different mounting holes, the drilling needs of different workpieces and different positions can be met. It has strong scalability, a wide range of applications, and the universal shaft transmission is stable and reliable.

[0016] Preferably, the control device is arranged on one side of the top of the workbench through a cantilever, and the control device is electrically connected to the drive motor, the first actuator, the second actuator and the detection switch;

[0017] The control device interacts with the detection switch via signals, and controls the start and stop of the drive motor, the first actuator and the second actuator, with high control accuracy.

[0018] Preferably, the first detection block and the second detection block are both threadedly connected with set screws, and the switch bracket is provided with a long hole along its length direction;

[0019] According to the different workpieces to be drilled, the installation positions of the first detection block, the second detection block and the detection switch are adjusted to meet the drilling needs of workpieces of various specifications and expand the scope of use.

[0020] Preferably, a first guide sleeve is provided at the position where the guide rod penetrates the lifting plate, and a second guide sleeve is provided at the position where the guide column penetrates the tooling plate;

[0021] Reduce the friction of guide rods and guide columns, reduce wear, increase service life, and ensure smooth and reliable lifting.

[0022] Preferably, the first actuator is a hydraulic cylinder, the fixed end of the first actuator is arranged on the workbench, the extended end of the first actuator is connected to the lifting plate, and the second actuator is a cylinder, the fixed end of the second actuator is arranged on the tooling bottom plate, and the extended end of the second actuator is connected to the tooling plate;

[0023] The hydraulic cylinder operates smoothly and has great power. It can reliably push the lifting plate and tooling components to drive the workpiece closer to the drill bit to complete the drilling operation. The cylinder switching response speed is fast, and it can drive the tooling base plate to quickly lift and switch, and perform hole drilling verification to ensure that the hole is completely drilled and improve the drilling quality.

[0024] Preferably, baffles are arranged around the upper surface of the workbench;

[0025] Shield the coolant during drilling to prevent droplets from splashing around and affecting the environment.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The lifting rod moves up and down with the lifting plate, and the feeding amount of the workpiece is controlled through the cooperation of the first detection block, the second detection block and the detection switch. The control is precise and the use safety is high. The positions of the first detection block, the second detection block and the detection switch can be adjusted according to the different workpiece models to meet the drilling needs of various types of workpieces, and the application range is wide;

[0028] 2. When drilling, the support plate supports the tooling plate, and the tooling plate and the support plate bear the force between the drill bit and the workpiece. The second actuator is not subjected to force, thereby avoiding damage to the second actuator and reducing the cost of use. After the drilling is completed, the second actuator drives the tooling plate to move up and down to ensure that the hole can be thoroughly drilled, and the drill bit is used to calibrate the hole to correct the deviation of the hole axis and improve the drilling quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The three-dimensional structure of the present invention is shown in FIG. Figure 1 ;

[0030] Figure 2 The three-dimensional structure of the present invention is shown in FIG. Figure 2 (Hide Shield);

[0031] Figure 3 It is a schematic diagram of the main structure of the present invention.

[0032] Among them, 1. workbench; 2. guide rod; 3. lifting plate; 4. fixing plate; 5. top plate; 6. first actuator; 7. lifting rod; 8. switch bracket; 9. first detection block; 10. second detection block; 11. detection switch; 12. long hole; 13. set screw; 14. tooling bottom plate; 15. tooling plate; 16. support plate; 17. second actuator; 18. guide column; 19. avoidance hole; 20. drive motor; 21. large gear shaft; 22. small gear shaft; 23. first pulley; 24. second pulley; 25. tool seat; 26. mounting hole; 27. chuck; 28. drill bit; 29. ​​universal shaft; 30. control device; 31. cantilever; 32. first guide sleeve; 33. second guide sleeve; 34. baffle; 35. belt; 36. guard. DETAILED DESCRIPTION

[0033] In order to make the technical means, technical features, invention objectives and technical effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific illustrations.

[0034] like Figure 1-Figure 3As shown, a CNC group drilling machine tool includes a workbench 1. The workbench 1 is used as an installation basis and is spliced ​​by profiles and steel plates. The overall structural strength is high. A double-door is installed on the front side of the workbench 1 to facilitate operation and maintenance of the inside of the workbench 1. Baffles 34 are installed around the top of the workbench 1 to block the coolant during drilling to prevent droplets from splashing and affecting the environment. Four guide rods 2 are connected to the top of the workbench 1. The four guide rods 2 are distributed in a matrix form. A lifting plate 3, a fixed plate 4 and a top plate 5 are connected to the four guide rods 2 in sequence from bottom to top. The lifting plate 3 can be lifted up and down along the guide rods 2. A tooling assembly is installed on the lifting plate 3. It is used for supporting and positioning the workpiece and for preliminary verification after drilling. A drilling tool assembly is installed on the fixed plate 4 for installing the drilling tool. A driving assembly is installed on the top plate 5. The driving assembly and the drilling tool assembly are transmission-connected to drive the drilling tool to rotate and realize the drilling operation. A positioning assembly is installed inside the workbench 1 to control the feed amount and ensure the drilling accuracy. A control device 30 is installed on one side of the top of the workbench 1 through a cantilever 31. The control device 30 can realize angle rotation around the cantilever 31 for easy operation. The tooling assembly, the driving assembly and the positioning assembly are electrically connected to the control device 30, and are uniformly controlled by the control device 30 with high control accuracy.

[0035] like Figure 1-Figure 3 As shown, the lifting and lowering of the lifting plate 3 is realized by the first actuator 6, and the first actuator 6 is installed inside the workbench 1. The first actuator 6 adopts a hydraulic cylinder, has a large output force, and runs smoothly. The fixed end of the first actuator 6 is installed on the workbench 1, and the extended end of the first actuator 6 penetrates the workbench 1 upward and is connected to the lifting plate 3. The lifting plate 3 is pushed up and down along the guide rod 2 by the first actuator 6. A first guide sleeve 32 is installed at the position where the guide rod 2 and the lifting plate 3 are penetrated and connected. The guide rod 2 is penetrated and installed in the first guide sleeve 32. When the lifting plate 3 moves, the lifting plate 3 is lifted by the first guide sleeve 32 to move smoothly, reduce the friction of the guide rod 2, reduce wear, increase the service life of the guide rod 2, and reduce the cost of use.

[0036] like Figure 1-Figure 3As shown, the tooling assembly includes a tooling base plate 14, a tooling plate 15, a support plate 16 and two second actuators 17. The tooling base plate 14 is connected to the top of the workbench 1. A guide column 18 is connected to the four corners of the tooling base plate 14. The top of the guide column 18 penetrates upward and slides onto the tooling plate 15. A second guide sleeve 33 is installed at the position where the guide column 18 penetrates the tooling plate 15 to improve the stability of the tooling plate 15 and reduce the wear of the guide column 18. A plurality of avoidance holes 19 are processed on the tooling plate 15, and the plurality of avoidance holes 19 are evenly distributed. The support plate 16 is installed on the tooling base plate 14 and is located below the tooling plate 15 to support the tooling plate 15. The two second actuators 17 are symmetrically installed on the tooling base plate 14 , and are located on both sides of the support plate 16. The second actuator 17 adopts a cylinder. The fixed end of the second actuator 17 is connected to the tooling base plate 14, and the extended end of the second actuator 17 is connected to the tooling plate 15. When the second actuator 17 is in a retracted state, the upper surface of the support plate 16 contacts the lower surface of the tooling plate 15. When drilling, the workpiece is mounted on the tooling plate 15 for support and positioning. The support plate 16 supports the tooling plate 15, and the support plate 16 bears the force exerted on the workpiece during drilling. The second actuator 17 is not subjected to force, thereby avoiding damage to the second actuator 17 due to force. After the hole is drilled through, the second actuator 17 drives the tooling plate 15 to switch up and down, and the hole is checked by the drill bit 28 to ensure that the hole is drilled thoroughly and the axial deviation of the hole is corrected.

[0037] like Figure 1-Figure 3As shown, the positioning assembly includes a lifting rod 7 and a switch bracket 8, both of which are installed inside the workbench 1. The upper end of the lifting rod 7 penetrates the workbench 1 upward and is connected to the lifting plate 3, and can be lifted and moved with the lifting plate 3. A first detection block 9 and a second detection block 10 are slidably sleeved on the lifting rod 7. The positions of the first detection block 9 and the second detection block 10 on the lifting rod 7 are adjustable, and are fixed by set screws 13 after adjustment. The switch bracket 8 is installed on the workbench 1, and a long strip hole 12 along its length direction is processed on the switch bracket 8. Three detection switches 11 are installed on the switch bracket 8, and the three detection switches 11 are all connected to the long strip hole 12, and the installation position can be adjusted along the long strip hole 12. Specifically, the detection switch at the bottom The switch 11 corresponds to the lower limit position of the retracted first actuator 6, the middle detection switch 11 corresponds to the position of the first actuator 6 actually extended during drilling, that is, the feed amount required for drilling, and the uppermost detection switch 11 corresponds to the upper limit position of the first actuator 6 extended to prevent the first actuator 6 from extending too much and causing interference damage. The first detection block 9 is installed at the lower end of the lifting rod 7 and corresponds to the lowermost detection switch 11. The second detection block 10 is installed in the middle of the lifting rod 7 and corresponds to the remaining two detection switches 11. Different detection switches 11 are triggered by the movement of the lifting rod 7 to judge the different lifting positions and states of the lifting plate 3, and to interact with the control device 30 for signals to control and execute different actions.

[0038] like Figure 1-Figure 3 As shown, the driving assembly includes a driving motor 20, a large gear shaft 21 and a plurality of small gear shafts 22. The driving motor 20 is installed on the top plate 5. The driving assembly is electrically connected to the control device 30. The start and stop of the driving motor 20 are controlled by the control device 30. The large gear shaft 21 and the plurality of small gear shafts 22 are rotatably installed on the top plate 5 through a bearing seat. The plurality of small gear shafts 22 are evenly distributed around the large gear shaft 21 and are all meshed with the large gear shaft 21 for transmission. The driving motor 20 is connected to the large gear shaft 21 by transmission, and the transmission mode is belt transmission, gear transmission or chain transmission. This embodiment is described by taking belt transmission as an example. A first belt is fixedly connected to the output end of the driving motor 20. The first pulley 23 and the second pulley 24 are fixedly mounted on the large gear shaft 21, and a belt 35 is connected between the first pulley 23 and the second pulley 24. The driving motor 20 drives the first pulley 23 to rotate, and the second pulley 24 and the large gear shaft 21 are driven to rotate through the transmission of the belt 35. The engagement of the large gear and the pinion shaft 22 drives several pinion shafts 22 to rotate at high speed to provide power for the drilling tool assembly. The transmission mode is flexible and diverse, easy to implement and reliable. In order to ensure safety during operation, a shield 36 is installed on the top plate 5, and the driving motor 20, the large gear shaft 21, the pinion shaft 22, the first pulley 23, the second pulley 24 and the belt 35 are all located inside the shield 36.

[0039] like Figure 1-Figure 3 As shown, the drilling tool assembly includes a tool seat 25, on which a plurality of mounting holes 26 are evenly processed in a matrix. The mounting holes 26 are distributed one by one with the avoidance holes 19. A chuck 27 is installed in the mounting hole 26. The chuck 27 can rotate in the mounting hole 26. The lower end of the chuck 27 passes downward through the mounting hole 26 and is connected to a drill bit 28. The chuck 27 is connected to the pinion shaft 22 through a universal shaft 29. By installing the chuck 27 in different mounting holes 26, the drilling needs of different workpieces and different positions can be met. The chuck 27 has strong expansibility and a wide range of applications. The transmission of the universal shaft 29 is stable and reliable.

[0040] The working principle of the present invention is:

[0041] When in use, according to the drilling position of the workpiece, the chuck 27 is installed in the corresponding mounting hole 26, the drill bit 28 is connected to the chuck 27, the pinion shaft 22 and the chuck 27 are connected through the universal shaft 29, the workpiece is manually installed and fixed on the tooling plate 15, and the installation position of the second detection block 10 on the lifting rod 7 and the position of the corresponding detection switch 11 are adjusted according to the model and quantity of the workpiece;

[0042] After the adjustment is completed, the corresponding program is selected and started on the control device 30. The driving motor 20 drives the large gear shaft 21 through the transmission of the first pulley 23, the second pulley 24 and the belt 35, thereby driving the plurality of small gear shafts 22 to rotate. Through the transmission of the universal shaft 29, the drill bit 28 is driven to rotate at a high speed. The first actuator 6 extends out, pushing the lifting plate 3 to move upward along the guide rod 2, and the workpiece approaches and contacts the drill bit 28. As the first actuator 6 continues to extend, the lifting plate 3 continues to rise to complete the drilling of the workpiece. After the drilling is completed, the head of the drill bit 28 is inserted into the avoidance hole 19 to prevent the drill bit 28 from interfering with the tooling plate 15, thereby avoiding the drill bit 28 from breaking or being damaged.

[0043] After the drilling is completed, the second actuator 17 is actuated, and by switching the control of the second actuator 17, the tooling plate 15 is driven to reciprocate up and down, and the hole is completely drilled through by the rotating drill bit 28 and the reciprocating movement of the tooling plate 15, and the hole is checked by the drill bit 28 to preliminarily correct the axis deviation of the hole;

[0044] In the initial state, the first actuator 6 is in a retracted state, and the first detection block 9 makes the detection switch 11 at the lower end in a triggered state. After starting work, the first actuator 6 extends, and the detection rod rises with the lifting plate 3. The trigger state of the detection switch 11 at the lower end disappears, and the state signal of the detection switch 11 is sent to the control device 30, and automatic operation is entered. When the second detection block 10 triggers the middle detection switch 11, the first actuator 6 is fed into place, the drilling is completed, and a signal is sent to the control device 30. The control device 30 determines the state according to the received signal and issues a corresponding control instruction.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made according to the content of the patent application scope of the present invention should belong to the technical scope of the present invention.

Claims

1. A CNC group drilling machine tool, characterized in that: The workbench (1) comprises four guide rods (2) arranged on the top of the workbench (1), the four guide rods (2) being arranged in a matrix, a lifting plate (3), a fixing plate (4) and a top plate (5) being arranged on the four guide rods (2) from bottom to top at intervals, the lifting plate (3) being arranged on the guide rods (2) in a manner that the lifting plate (3) can be lifted and lowered by a first actuator (6), a tooling assembly is arranged on the lifting plate (3), the fixing plate (4) is fixedly arranged on the guide rods (2), a drilling tool assembly is arranged on the upper surface of the fixing plate (4), the top plate (5) is fixedly arranged on the upper end of the guide rods (2), a driving assembly is arranged on the top plate (5), the driving assembly is connected to the drilling tool assembly in a transmission manner, a positioning assembly is arranged inside the workbench (1) for controlling the feed amount, a control device (30) is arranged on one side of the top of the workbench (1), and the tooling assembly, the driving assembly and the positioning assembly are electrically connected to the control device (30); The tooling assembly comprises a tooling base plate (14), a tooling plate (15), a support plate (16) and two second actuators (17); a guide column (18) is provided at each of the four corners of the tooling base plate (14); the top of the guide column (18) penetrates upward and is slidably mounted on the tooling plate (15); a plurality of avoidance holes (19) are evenly distributed on the tooling plate (15); the support plate (16) is provided on the tooling base plate (14) and is located below the tooling plate (15); and the two second actuators (17) are symmetrically provided on the tooling base plate (14) and are located on both sides of the support plate (16); The driving assembly comprises a driving motor (20), a large gear shaft (21) and a plurality of small gear shafts (22); the driving motor (20) is arranged on the top plate (5); the large gear shaft (21) and the plurality of small gear shafts (22) are rotatably arranged on the top plate (5); the plurality of small gear shafts (22) are evenly distributed around the large gear shaft (21) and are all meshed with the large gear shaft (21) for transmission; the driving motor (20) and the large gear shaft (21) are transmission-connected, and the transmission mode is belt transmission, gear transmission or chain transmission; The drilling tool assembly comprises a tool seat (25), a plurality of mounting holes (26) are evenly arranged in a matrix on the tool seat (25), the mounting holes (26) correspond one to another in the upper and lower directions of the avoidance holes (19), a chuck (27) is rotatably arranged in the mounting hole (26), the lower end of the chuck (27) passes downward through the mounting hole (26) and is connected to a drill bit (28), and the chuck (27) is connected to the pinion shaft (22) via a universal shaft (29); The first actuator (6) extends and the lifting plate (3) rises to complete drilling of the workpiece. During drilling, the support plate (16) bears the force exerted on the workpiece during drilling. After drilling is completed, the second actuator (17) drives the tooling plate (15) to move up and down, and the hole is checked by the drill bit (28) to ensure that the hole is thoroughly drilled and the axial deviation of the hole is corrected.

2. The CNC group drilling machine tool according to claim 1, characterized in that: The positioning assembly comprises a lifting rod (7) and a switch bracket (8); the upper end of the lifting rod (7) penetrates upward through the workbench (1) and is connected to the lifting plate (3); a first detection block (9) and a second detection block (10) are mounted on the lifting rod (7); the switch bracket (8) is arranged on the workbench (1); and three detection switches (11) are arranged at intervals on the switch bracket (8).

3. The CNC group drilling machine tool according to claim 2, characterized in that: The control device (30) is arranged on one side of the top of the workbench (1) via a cantilever (31), and the control device (30) is electrically connected to the drive motor (20), the first actuator (6), the second actuator (17), and the detection switch (11).

4. The CNC group drilling machine tool according to claim 2, characterized in that: The first detection block (9) and the second detection block (10) are both threadedly connected with set screws (13), and the switch bracket (8) is provided with a long hole (12) along its length direction.

5. The CNC group drilling machine tool according to claim 1, characterized in that: A first guide sleeve (32) is provided at a position where the guide rod (2) penetrates the lifting plate (3), and a second guide sleeve (33) is provided at a position where the guide column (18) penetrates the tooling plate (15).

6. The CNC group drilling machine tool according to claim 1, characterized in that: The first actuator (6) is a hydraulic cylinder, the fixed end of the first actuator (6) is arranged on the workbench (1), and the extended end of the first actuator (6) is connected to the lifting plate (3); the second actuator (17) is a cylinder, the fixed end of the second actuator (17) is arranged on the tooling bottom plate (14), and the extended end of the second actuator (17) is connected to the tooling plate (15).

7. The CNC group drilling machine tool according to claim 1, characterized in that: Baffles (34) are arranged around the upper surface of the workbench (1).

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