Ultra-high speed numerical control metal band saw machine

Abstract

The present application belongs to the technical field of sawing machine, and particularly relates to a super-high-speed numerical control metal band sawing machine. The present application provides a super-high-speed numerical control metal band sawing machine, aiming at solving the problem of poor stability of the sawing machine when sawing workpieces. The super-high-speed numerical control metal band sawing machine comprises a machine body, a driving assembly arranged on the machine body and used for driving the rotation of a sawing belt, the driving assembly comprising a gear transmission mechanism and a damper used for eliminating the transmission gap of the gear transmission mechanism; a clamp assembly is further arranged on the machine body, and the clamp assembly comprises an auxiliary positioner used for assisting in the positioning of a workpiece, the auxiliary positioner applying an action force to the workpiece, the action force being opposite to the action force applied to the workpiece by the sawing belt, so that the workpiece is stably stressed and the vibration in the sawing process is reduced.

Description

Technical Field

[0001] This invention belongs to the field of band sawing technology, specifically relating to an ultra-high speed CNC metal band saw. Background Technology

[0002] Band saws are machine tools used for sawing various metal materials. They are classified by structure into horizontal and vertical types; and by function into semi-automatic, fully automatic, and CNC types. Horizontal band saws can be further divided into double-column and scissor types. Band saws are common industrial equipment used for metal cutting, and are frequently used in industries such as: punching die making, shoe mold making, gravity die casting of copper and aluminum, automotive industry, hardware manufacturing and various internal equipment production lines, aerospace industry, metal lettering for signs, steel materials, machinery manufacturing, home appliances, vibratory feeders, and tire manufacturing.

[0003] Existing band saws include a clamping assembly for holding workpieces. The clamping assembly is generally a clamp. When using a clamp to hold a workpiece, although it can achieve a certain clamping effect, the workpiece is subjected to force on one side when the band saw is cutting the workpiece, which causes poor stability during the workpiece clamping process. Summary of the Invention

[0004] This invention provides an ultra-high-speed CNC metal band saw, which aims to solve the problem of poor stability when sawing workpieces in the prior art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A high-speed CNC metal band saw includes a machine body, on which a drive assembly for driving the saw band to rotate is provided. The drive assembly includes a gear transmission mechanism and a damper for eliminating transmission backlash in the gear transmission mechanism.

[0007] The drive assembly includes a drive saw wheel and a driven saw wheel, the saw band is disposed on the drive saw wheel and the driven saw wheel, the drive assembly also includes a frame, and the driven saw wheel is fixed to the frame by a saw wheel tensioning assembly;

[0008] The tensioning assembly includes a wheel frame and a tensioning cylinder. The driven saw wheel is rotatably connected to the wheel frame, and the wheel frame is slidably connected to the frame body.

[0009] The machine body is also provided with a clamping assembly for holding the workpiece. The clamping assembly includes a clamping arm and an auxiliary positioner for assisting the clamping assembly in positioning the workpiece. The auxiliary positioner includes a contact plate that contacts the workpiece and a positioning motor that drives the contact plate to rotate. The direction of the force applied by the contact plate to the workpiece is opposite to the direction of the force applied by the saw blade to the workpiece.

[0010] The machine body is also provided with a feeding component, which drives the saw blade to move closer to or away from the workpiece through the drive component.

[0011] A further improved solution: the auxiliary positioner is slidably connected to the machine body, the sliding direction of the auxiliary positioner is parallel to the feeding direction of the feed assembly driving the saw blade, and the machine body is also provided with an elastic support that pushes the auxiliary positioner to make the contact plate contact the workpiece.

[0012] Based on the above technical solution: the auxiliary positioner is slidably connected to the machine body. The auxiliary positioner can move away from or towards the workpiece, thereby preventing the saw blade from contacting the contact wheel. When the saw blade is close to the contact plate, the contact plate can be moved away from the saw blade, so that the saw blade will not contact the contact plate and the saw blade is not easily damaged.

[0013] A further improved solution: When the feed assembly causes the saw band to cut into the workpiece to a depth greater than half the diameter of the workpiece's inscribed circle and less than 2 / 3 of the diameter of the workpiece's inscribed circle, the feed assembly overcomes the force of the elastic support and pushes the auxiliary positioner to disengage the contact plate from the workpiece.

[0014] Based on the above technical solution: After the saw blade cuts into the workpiece to a certain depth, the contact plate disengages from the workpiece, resulting in uniform force on the workpiece. For example, when the saw blade cuts the lower half of the workpiece, the force exerted on the workpiece by the saw blade decreases, that is, the rotation center of the workpiece under the force of the saw blade moves downward, thereby shortening the rotation lever arm of the workpiece. The contact plate contacts the lower side of the workpiece, causing the workpiece to bear the force applied by the contact plate. Therefore, when the saw blade cuts into the workpiece to a certain depth, the contact plate disengages from the workpiece, resulting in uniform force and less vibration during the sawing process.

[0015] A further improved solution: the force exerted by the contact plate on the workpiece is equal to the force exerted by the saw blade on the workpiece, and the workpiece is located between the saw blade and the contact plate.

[0016] Based on the above technical solution: the force exerted by the contact plate on the workpiece is equal to the force exerted by the saw blade on the workpiece. The saw blade exerts a force on the workpiece from above, and the contact plate exerts a force on the workpiece from the lower end of the workpiece in the opposite direction and of equal magnitude. This causes the force exerted by the saw blade on the workpiece and the force exerted by the contact plate on the workpiece to cancel each other out, and the workpiece is in a stationary state.

[0017] A further improved solution: the thickness of the contact plate is equal to the thickness of the saw blade, and the contact plate is located directly below the saw blade.

[0018] Based on the above technical solution: the thickness of the contact plate is equal to the thickness of the saw blade, the contact plate is located directly below the saw blade, and the contact plate contacts the workpiece. During the rotation of the contact plate, the surface of the workpiece may be damaged. However, since the contact plate is located directly below the workpiece, even if the contact plate damages the surface of the workpiece, the damaged part will be cut off by the saw blade, thereby ensuring that the surface accuracy of the workpiece meets the requirements.

[0019] A further improved solution: the thickness of the contact plate is not less than the thickness of the saw blade, and the contact plate is located on one side of the saw blade; or, the contact plate is provided on both sides of the saw blade.

[0020] Based on the above technical solution: the thickness of the contact plate is not less than the thickness of the saw blade. When there are no precision requirements on the surface of the workpiece, the contact plate and the saw blade can be staggered to give the contact plate and the workpiece a larger contact area.

[0021] A further improved solution: The machine body is also equipped with a control component, the tensioning cylinder is controlled by the control component, and the feed component also includes an upper pressure detection component for detecting the pressure of the saw band, the upper pressure detection component being communicatively connected to the control component.

[0022] Based on the above technical solution: the pressure detection component communicates with the control component, and the control component can detect the pressure on the saw belt through the pressure detection component.

[0023] A further improved solution: The pressure detection component includes a belt presser, on which a top rod is provided that contacts the saw blade. The top rod is slidably connected to the belt presser. The belt presser is also equipped with a servo motor, which drives the detection wheel to rotate. The top rod is slidably connected to the belt presser, and the saw blade pushes the top rod to contact the detection wheel.

[0024] Based on the above technical solution: the top rod is slidably connected to the pressure belt device, and the saw blade pushes the top rod to contact the detection wheel. After the top rod contacts the detection wheel, due to the certain friction between the top rod and the detection wheel, the detection wheel can withstand a certain frictional resistance during rotation. By detecting this frictional resistance, the pressure borne by the saw blade can be calculated.

[0025] A further improved solution: The control component integrates a memory that stores sawing work data, including workpiece material, saw blade feed speed, saw blade tension parameters, and saw blade linear speed. The control component controls the drive component and the feed component based on the friction between the detection wheel and the push rod and the sawing work data.

[0026] Based on the above technical solution: The control component integrates a memory that stores sawing work data. Based on the sawing work data, the control component can output reasonable control parameters to control the operation of the feed component and other components.

[0027] A further improved solution: the drive assembly includes a drive motor, and the damper is disposed on the output shaft of the drive motor; or, the gear transmission mechanism includes a drive shaft, and the damper is disposed on the drive shaft.

[0028] Based on the above technical solution: the damper is installed on the output shaft of the drive motor. The damper can effectively eliminate the backlash between gears, making the drive assembly more stable during movement. The damper's placement on the drive shaft also facilitates the reduction of backlash between gears in the gear transmission mechanism, further enhancing the stability of the drive assembly during movement.

[0029] The beneficial effects of this invention are as follows:

[0030] A high-speed CNC metal band saw includes a machine body, on which a drive assembly is mounted. The drive assembly includes a damper. Adding a damper after the main drive can effectively eliminate gear backlash in the reducer, thereby giving the drive assembly higher stability, reducing noise during operation, and improving the stability of the drive assembly.

[0031] The machine body is also equipped with a clamping assembly, which includes an auxiliary locator. The auxiliary locator is used to assist in positioning the workpiece. The auxiliary locator applies a force to the workpiece, which is opposite to the force applied to the workpiece by the saw blade. The force applied to the workpiece by the auxiliary locator is opposite to the force applied to the workpiece by the saw blade, so that the workpiece is under stable force and vibration during the sawing process is reduced.

[0032] The machine body is also equipped with a feeding component, which includes an upper pressure detection component. The detection wheel is rotated by a servo motor. When the push rod is pushed upward by pressure below, the push rod and the detection wheel come into contact and generate a frictional force. The servo motor detects this frictional force and automatically converts it into a current pulse. The control component automatically adjusts the saw belt feed and linear speed.

[0033] In actual sawing, 718 material, 800mm wide mold steel can achieve a feed rate of 12mm per minute, a cutting efficiency of 90cm²-100cm², and a saw blade life of up to 8m². Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For users of ordinary skills in the art, other related drawings can be obtained from these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the internal structure of an ultra-high-speed CNC metal band saw according to the present invention, in the first direction.

[0036] Figure 2 yes Figure 1 Enlarged view of point A in the middle.

[0037] Figure 3 This is a schematic diagram of the internal structure of an ultra-high-speed CNC metal band saw according to the present invention, in the second direction.

[0038] Figure 4 This is a schematic diagram of the force on a workpiece during sawing in an ultra-high-speed CNC metal band saw of the present invention.

[0039] Figure 5 This is a front view of the feed assembly in an ultra-high-speed CNC metal band saw according to the present invention.

[0040] Figure 6 This is a schematic diagram of the drive assembly in an ultra-high-speed CNC metal band saw according to the present invention.

[0041] Figure 7 A schematic diagram of a tensioning component in an ultra-high-speed CNC metal band saw according to the present invention.

[0042] Figure 8 This is a schematic diagram of an ultra-high-speed CNC metal band saw with a housing according to the present invention.

[0043] Explanation of the labels in the diagram:

[0044] 1-Machine body; 2-Drive assembly; 3-Clamping assembly; 31-Auxiliary positioner; 32-Contact plate; 33-Clamping arm; 4-Control assembly; 5-Driven saw wheel; 6-Driven saw wheel; 7-Tensioning assembly; 8-Workpiece; 9-Saw band; 10-Feed assembly. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. All other embodiments obtained by users of the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0046] refer to Figures 1 to 8 This embodiment provides an ultra-high speed CNC metal band saw, including a machine body 1. The machine body 1 is provided with a drive assembly 2 for driving the saw band to rotate. The drive assembly 2 includes a gear transmission mechanism and a damper for eliminating the transmission backlash of the gear transmission mechanism.

[0047] The machine body 1 is also provided with a clamping assembly 3 for clamping the workpiece 8. The clamping assembly 3 includes a clamping arm 33 and an auxiliary positioner 31 for assisting the clamping assembly 3 in positioning the workpiece 8. The auxiliary positioner 31 includes a contact plate 32 that contacts the workpiece 8 and a positioning motor that drives the contact plate 32 to rotate. The direction of the force applied by the contact plate 32 to the workpiece 8 is opposite to the direction of the force applied by the saw blade to the workpiece 8.

[0048] The machine body 1 is also provided with a feeding component 10. The feeding component 10 drives the saw blade to move closer to or away from the workpiece 8 through the driving component 2. The feeding component 10 also includes an upper pressure detection component for detecting the pressure of the saw blade. The upper pressure detection component is communicatively connected to the control component 4.

[0049] The pressure detection assembly includes a belt presser, on which a top rod is provided that contacts the saw blade. The top rod is slidably connected to the belt presser. A servo motor is also provided on the belt presser. The servo motor drives the detection wheel to rotate. The top rod is slidably connected to the belt presser, and the saw blade pushes the top rod to contact the detection wheel.

[0050] An outer shell can be installed on the main body 1 to protect personnel safety.

[0051] refer to Figures 1 to 8 The control component 4 integrates a memory that stores sawing work data, including the material of the workpiece 8, the saw blade feed speed, the saw blade tension parameters, and the saw blade linear speed. The control component 4 controls the drive component 2 and the feed component 10 based on the friction between the detection wheel and the top rod and the sawing work data.

[0052] The servo motor can be controlled by the control component 4, or the servo motor can be communicatively connected to the control component 4.

[0053] The contact plate 32 may include a metal plate body and a contact layer that contacts the workpiece 8. The contact layer may be bonded to the plate body and may be made of a wear-resistant material, such as rubber. The contact plate 32 contacts the workpiece, and applies a force to the workpiece 8 using the friction between the contact plate 32 and the workpiece 8. Therefore, there should be a certain amount of friction between the contact plate 32 and the workpiece 8. During the sawing process, coolant can be discharged through the contact plate 32, which can flush away the wear debris on the contact plate 32, maintaining a reasonable friction between the contact plate 32 and the workpiece 8 to achieve the effect of the contact plate 32 applying a force to the workpiece 8.

[0054] refer to Figures 1 to 8 Specifically: the auxiliary positioner 31 is slidably connected to the machine body 1, and the sliding direction of the auxiliary positioner 31 is parallel to the feeding direction of the feed assembly 10 driving the saw blade. The machine body 1 is also provided with an elastic support that pushes the auxiliary positioner 31 to make the contact plate 32 contact the workpiece 8.

[0055] The elastic support can be springs, with at least four springs forming the elastic support. The upper end of the spring can be fixed to the machine body 1, and the lower end of the spring can be fixed to the positioning motor. Both ends of the spring can be fixed to the machine body 1 and the positioning motor respectively by screws.

[0056] Wherein: when the feed assembly 10 causes the saw band to cut into the workpiece 8 to a depth greater than half the diameter of the inscribed circle of the workpiece 8 and less than 2 / 3 of the diameter of the inscribed circle of the workpiece 8, the feed assembly 10 overcomes the force of the elastic support and pushes the auxiliary positioner 31 to disengage the contact plate 32 from the workpiece 8.

[0057] When the saw band cuts into the workpiece 8 to a certain depth, the magnitude of the force exerted by the saw band on the workpiece 8 remains unchanged. However, after the saw band has cut into the workpiece 8 to a certain depth, the magnitude of the force exerted by the saw band on the workpiece 8 that causes the workpiece 8 to rotate will decrease. That is, after the saw band has cut into the workpiece 8 to a certain depth, the lever arm of the force exerted by the saw band on the workpiece 8 that causes the workpiece 8 to rotate will decrease, thereby reducing the force exerted by the saw band on the workpiece 8. At this time, the contact plate 32 may not contact the workpiece 8, so that the workpiece 8 is subjected to more uniform force.

[0058] refer to Figure 3 , Figure 5A top column can be set on the drive assembly 2 or the feed assembly 10. The top column moves synchronously with the saw blade. A through hole that cooperates with the top column can be set on the machine body 1. The top column contacts the auxiliary positioner 31 through the through hole. During the descent of the saw blade, the top column descends together. When the saw blade descends to the position where the contact plate 32 needs to be separated from the workpiece 8, the top column interferes with the auxiliary positioner 31 and overcomes the force of the elastic support, causing the auxiliary positioner 31 to move away from the workpiece 8, thereby causing the contact plate 32 to disengage from the workpiece 8.

[0059] Specifically: the force exerted by the contact plate 32 on the workpiece 8 is equal to the force exerted by the saw blade on the workpiece 8, and the workpiece 8 is located between the saw blade and the contact plate 32.

[0060] Wherein: the thickness of the contact plate 32 is equal to the thickness of the saw blade, and the contact plate 32 is located directly below the saw blade.

[0061] refer to Figures 1 to 4 Another way to set the contact plate 32 is that the thickness of the contact plate 32 is not less than the thickness of the saw blade, and the contact plate 32 is located on one side of the saw blade; or, the contact plate 32 is provided on both sides of the saw blade.

[0062] When contact discs 32 are provided on both sides of the saw blade, there are two contact discs 32, and the two contact discs 32 can be driven by the same positioning motor. The two contact discs 32 can be mounted on the main shaft of the positioning motor by a key connection.

[0063] The machine body 1 can be provided with a mounting slot for installing the auxiliary positioner 31. The positioning motor is slidably connected in the mounting slot, that is, the positioning motor is fixed to the machine body 1 by an elastic support, and the positioning motor slides along the mounting slot so that the contact plate 32 can contact or detach from the workpiece 8. The elastic support can be fixed to the machine body 1 by bolts.

[0064] Specifically: the drive assembly 2 includes a drive saw wheel 5 and a driven saw wheel 6, the saw band is disposed on the drive saw wheel 5 and the driven saw wheel, the drive assembly 2 also includes a frame, and the driven saw wheel is fixed to the frame by a tensioning assembly 7.

[0065] Wherein: the tensioning assembly 7 includes a wheel frame and a tensioning cylinder, the tensioning cylinder is controlled by the control assembly 4, the driven saw wheel is rotatably connected to the wheel frame, and the wheel frame is slidably connected to the frame body.

[0066] Specifically: the drive assembly 2 includes a drive motor, and the damper is disposed on the output shaft of the drive motor.

[0067] Alternatively: the gear transmission mechanism includes a drive shaft, and the damper is disposed on the drive shaft.

[0068] The damper is essentially a gear backlash elimination structure in existing technology. Gear backlash elimination structures are common in existing technologies, and their installation method follows existing techniques. The damper can be a double-gear backlash elimination structure. Its working principle is as follows: Double-gear backlash elimination refers to the elimination of the gap between two gears through their meshing action, thereby achieving precision transmission. The working principle of double-gear backlash elimination is mainly based on the meshing action of two gears. When the two gears mesh, the gap between them is eliminated. This is because the gear tooth profile ensures the meshing between the gears, thus achieving precision transmission. At the same time, the gear tooth profile design can also control the clearance between the gears to ensure the accuracy and reliability of the gear transmission.

[0069] The advantages of double-gear backlash elimination are that it can increase the precision of mechanical transmission, reduce noise, and improve transmission efficiency. This is because backlash elimination technology eliminates the gap between gears, thereby reducing losses and friction during gear transmission and improving transmission efficiency. At the same time, backlash elimination technology can also reduce vibration and noise during gear transmission, making mechanical equipment smoother and quieter.

[0070] The working principle of this embodiment:

[0071] refer to Figure 4 In the actual sawing process, the workpiece 8 is first clamped on the fixture assembly 3. Then, the material of the workpiece 8 is input into the control assembly 4. The control assembly 4 automatically queries the data in the memory and determines the sawing data according to the material of the workpiece 8.

[0072] Then, the controller controls the drive assembly 2 to drive the workpiece 8. The drive assembly 2 drives the saw blade to rotate. At this time, the saw blade is not in contact with the workpiece 8. When the saw blade moves to a position close to the workpiece 8, the control assembly 4 controls the feed feeder, tension cylinder and drive assembly 2 according to the sawing work data, so that the saw blade has a reasonable feed speed, linear speed and tension force.

[0073] Simultaneously, the control component 4 controls the positioning motor to operate, which drives the contact plate 32 to rotate. The contact plate 32 contacts the workpiece 8 and applies a force to the workpiece 8. This force is opposite to the force applied by the saw blade to the workpiece 8, thereby keeping the workpiece 8 stable. Specifically, the rotation direction of the saw blade 9 is B, the rotation direction of the contact plate 32 is E, the direction of the force applied by the saw blade to the workpiece 8 is C, and the direction of the force applied by the contact plate 32 to the workpiece 8 is D. C and D are equal in magnitude and opposite in direction, thereby effectively reducing the vibration of the workpiece 8 during the sawing process and improving the sawing efficiency.

[0074] This invention is not limited to the above-mentioned optional embodiments. Under the premise of non-contradiction, the various solutions can be combined arbitrarily. Anyone can derive other forms of products under the guidance of this invention. However, no matter what changes are made in their shape or structure, all technical solutions that fall within the scope of the claims of this invention are within the protection scope of this invention.

Claims

1. A high-speed CNC metal band saw, characterized in that: The device includes a body, on which a drive assembly for driving the saw band to rotate is provided. The drive assembly includes a gear transmission mechanism and a damper for eliminating transmission backlash in the gear transmission mechanism. The drive assembly includes a drive saw wheel and a driven saw wheel, the saw band is disposed on the drive saw wheel and the driven saw wheel, the drive assembly also includes a frame, and the driven saw wheel is fixed to the frame by a saw wheel tensioning assembly; The tensioning assembly includes a wheel frame and a tensioning cylinder. The driven saw wheel is rotatably connected to the wheel frame, and the wheel frame is slidably connected to the frame body. The machine body is also provided with a clamping assembly for holding the workpiece. The clamping assembly includes a clamping arm and an auxiliary positioner for assisting the clamping assembly in positioning the workpiece. The auxiliary positioner includes a contact plate that contacts the workpiece and a positioning motor that drives the contact plate to rotate. The direction of the force applied by the contact plate to the workpiece is opposite to the direction of the force applied by the saw blade to the workpiece. The machine body is also provided with a feeding component, which drives the saw blade to move closer to or away from the workpiece through the driving component; The auxiliary positioner is slidably connected to the machine body, and the sliding direction of the auxiliary positioner is parallel to the feeding direction of the feed component driving the saw blade. The machine body is also provided with an elastic support that pushes the auxiliary positioner to make the contact plate contact the workpiece. When the feed assembly causes the saw band to cut into the workpiece to a depth greater than half the diameter of the workpiece's inscribed circle and less than 2 / 3 of the diameter of the workpiece's inscribed circle, the feed assembly overcomes the force of the elastic support and pushes the auxiliary positioner to disengage the contact plate from the workpiece.

2. The ultra-high-speed CNC metal band saw according to claim 1, characterized in that: The force exerted by the contact plate on the workpiece is equal to the force exerted by the saw blade on the workpiece, and the workpiece is located between the saw blade and the contact plate.

3. The ultra-high-speed CNC metal band saw according to claim 2, characterized in that: The thickness of the contact plate is equal to the thickness of the saw blade, and the contact plate is located directly below the saw blade.

4. The ultra-high-speed CNC metal band saw according to claim 3, characterized in that: The thickness of the contact plate is not less than the thickness of the saw blade, and the contact plate is located on one side of the saw blade; or, the contact plate is provided on both sides of the saw blade.

5. The ultra-high-speed CNC metal band saw according to claim 1, characterized in that: The machine body is also equipped with a control component, the tensioning cylinder is controlled by the control component, and the feed component also includes an upper pressure detection component for detecting the pressure of the saw band, the upper pressure detection component being communicatively connected to the control component.

6. The ultra-high-speed CNC metal band saw according to claim 5, characterized in that: The pressure detection assembly includes a belt presser, on which a top rod is provided that contacts the saw blade. The top rod is slidably connected to the belt presser. A servo motor is also provided on the belt presser. The servo motor drives the detection wheel to rotate. The top rod is slidably connected to the belt presser, and the saw blade pushes the top rod to contact the detection wheel.

7. The ultra-high-speed CNC metal band saw according to claim 6, characterized in that: The control component integrates a memory that stores sawing data, including workpiece material, saw band feed speed, saw band tension parameters, and saw band linear speed. The control component controls the drive component and the feed component based on the friction between the detection wheel and the push rod and the sawing data.

8. The ultra-high-speed CNC metal band saw according to claim 1, characterized in that: The drive assembly includes a drive motor, and the damper is disposed on the output shaft of the drive motor; or, the gear transmission mechanism includes a drive shaft, and the damper is disposed on the drive shaft.

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