Deep hole thread machining device and machining method thereof

Abstract

The invention relates to the field of deep hole thread machining, and discloses a deep hole thread machining device and a deep hole thread machining method.The deep hole thread machining method is characterized by comprising the steps that first-time tapping is conducted, specifically, a first screw tap is installed on a rigid machining cutter handle, first-time tapping is conducted through the rigid machining cutter handle, and a rough machining threaded hole is formed; in the tool setting step, a second screw tap is installed on the floating machining tool handle, tool setting is conducted on the second screw tap and the rough machining threaded hole, in the secondary tapping step, secondary tapping is conducted through the floating machining tool handle to form a finish machining threaded hole, and the thread pitch of the finish machining threaded hole is consistent with the thread pitch of the rough machining threaded hole.

Description

Technical Field

[0001] The invention relates to the field of deep hole thread processing, and more specifically to a deep hole thread processing device and a processing method thereof. Background Art

[0002] Deep hole threads usually refer to holes with a hole depth and hole diameter ratio greater than 6. The hole diameter is often too large, tapered or skewed, making deep hole thread processing a difficult problem in production. In addition, thread processing is generally arranged in the last few processes of part processing. Using traditional methods to tap difficult-to-process materials can easily cause the tap to break, resulting in scrapped parts, delaying the construction period and causing great economic losses. Therefore, it is imperative to solve the processing of small deep hole threads in difficult-to-process materials. In the field of mechanical manufacturing, deep hole thread processing has always faced many challenges. When the depth of the threaded hole to be processed is large, the conventional single processing method is prone to various problems. For example, the tool is unevenly stressed in the deep and long hole, which will lead to increased pitch error and roundness error of the thread; the deep and long processing path makes chip removal difficult, and chip accumulation is easy to scratch the processed surface, affecting the surface quality; the tool works in the deep hole for a long time, the heat dissipation conditions are poor, the tool wear is aggravated, and the processing accuracy and tool life are further reduced. These problems seriously affect the quality and efficiency of deep hole thread processing and limit the application of related components in high-precision equipment. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide a deep hole thread processing device and a processing method thereof, so as to overcome the above-mentioned defects in the prior art.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A deep hole thread processing method, the deep hole thread processing method comprising:

[0006] A tapping step: installing a first tap on the rigid processing tool holder, and performing a first tapping with the rigid processing tool holder to form a rough-processed threaded hole.

[0007] Tool setting step: installing a second tap on the floating processing tool holder, and aligning the second tap with the rough processing threaded hole.

[0008] Secondary tapping step: using the floating machining tool holder to perform secondary tapping to form a finish-machined threaded hole, the pitch of the finish-machined hole is consistent with the pitch of the rough-machined threaded hole.

[0009] In the present invention, preferably, the tool setting step is configured with a tool setting strategy, and the tool setting strategy includes

[0010] The image acquisition module acquires the image of the processed hole, and the image recognition module acquires the image of the processed hole and identifies the rough-machined threaded hole and the tool reference point, wherein the tool reference point is specifically the tool starting position in actual processing, identifies the tool cutting edge on the second tap and calculates the tool displacement, wherein the tool displacement is specifically the direction, distance and rotation angle required to move the second tap until the tool cutting edge coincides with the tool reference point.

[0011] In the present invention, preferably, the deep hole thread processing method also includes a deviation correction step, and the deviation correction step includes obtaining a floating displacement and a tool holder force value, wherein the floating displacement is specifically a radial floating displacement of the floating processing tool holder during the secondary tapping step, and the tool holder force value is specifically a change trend of the force acting on the floating processing tool holder during the secondary tapping step, and the floating deviation amount is calculated based on the floating displacement and the tool holder force value, and the tool displacement is corrected based on the floating deviation amount.

[0012] In the present invention, preferably, the deep hole thread processing method is configured with a tool state monitoring strategy, and the tool state monitoring strategy is performed when tapping is performed using a floating tool holder. The tool state monitoring strategy includes obtaining the cutting temperature, tool holder vibration, abnormal sound and calculating the tool processing state based on the processing state model. The cutting temperature is specifically the temperature of the tool cutting part, and the tool holder vibration is specifically the vibration amplitude of the tool holder. If an abnormal sound occurs, it reflects an abnormal processing state, and the processing state of the floating processing tool holder is regulated based on the tool processing state.

[0013] In the present invention, preferably, the state control strategy of the floating tool holder includes reducing the feed speed to continue processing and repeatedly collecting the tool vibration amount if the tool vibration amount exceeds the preset vibration amount; if the tool vibration amount can be reduced to the preset vibration amount, processing is performed at the adjusted feed speed; if the tool vibration amount cannot be reduced to the preset vibration amount, stopping the tool and issuing a tool change prompt.

[0014] In the present invention, preferably, the state control strategy of the floating tool holder includes real-time collection of sound signals during the processing, and transmitting them to a sound analysis module built into the machine tool control system. By comparing and analyzing them with a preset normal sound pattern, if the sound is judged to be abnormal, an alarm is immediately sounded and the machine is shut down.

[0015] In the present invention, preferably, the state control strategy of the floating tool holder includes a temperature sensor that monitors the tool cutting temperature in real time. When the temperature reaches the warning temperature range, the system issues a warning prompt on the operation interface. When the temperature exceeds the conventional temperature threshold and is less than the warning temperature, the cutting speed is reduced and the cutting fluid flow rate is increased. The tool cutting temperature is repeatedly collected and the temperature drops to a preset safety temperature range.

[0016] A deep hole thread processing device is provided, which uses any one of the deep hole thread processing methods described above, and the deep hole thread processing device includes a radial floating tool holder.

[0017] Beneficial effects of the present invention:

[0018] 1. The present invention is completed in two steps through the tapping step, and the first tapping and the second tapping are performed in sequence. A certain processing error can be allowed in the first tapping, which is equivalent to rough processing. The second tapping is performed after the tool is aligned. The processing conditions are improved in the second tapping, and the heat dissipation and chip removal capabilities are improved. The force of the tool is also improved, thereby improving the reliability and accuracy of deep hole thread processing, while reducing the wear of the tool, and improving the processing accuracy and tool life;

[0019] 2. The present invention utilizes a tool setting strategy to set the tool, which has a good effect. The tool setting error can be judged and corrected according to the actual force conditions during cutting. The tool status can be calculated in combination with the variables collected during the thread processing process, thereby facilitating timely replacement of the tool and timely adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the deep hole thread structure to be processed;

[0021] Figure 2 It is a schematic diagram of the process of the deep hole thread processing method of this embodiment. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0025] Please also see Figure 1 and Figure 2 , this embodiment provides a deep hole thread processing method, the deep hole thread processing method comprising:

[0026] A tapping step: installing a first tap on the rigid processing tool holder, and performing a first tapping with the rigid processing tool holder to form a rough-processed threaded hole.

[0027] Tool setting step: installing a second tap on the floating processing tool holder, and aligning the second tap with the rough processing threaded hole.

[0028] Secondary tapping step: using the floating machining tool holder to perform secondary tapping to form a finish-machined threaded hole, the pitch of the finish-machined hole is consistent with the pitch of the rough-machined threaded hole.

[0029] The present invention is completed in two steps through the tapping step, and the first tapping and the second tapping are performed in sequence. A certain processing error can be allowed in the first tapping, which is equivalent to rough processing. The second tapping is performed after the tool is aligned. The processing conditions are improved during the second tapping, and the heat dissipation and chip removal capabilities are improved. The force of the tool is also improved, thereby improving the reliability and accuracy of deep hole thread processing, while slowing down the wear of the tool, improving the processing accuracy and tool life. Using two tapping steps can reduce the cutting amount of a single processing, reduce cutting heat and reduce vibration during the cutting process.

[0030] In a tapping step, select a suitable drill bit according to the workpiece material type, such as aluminum alloy, steel, etc. For medium carbon steel workpieces, select a carbide drill with a diameter of [D1] mm. Install the drill bit on the machine tool, set the speed to [X1] rpm, and the feed rate to [Y1] mm / rev. During the processing, the vibration sensor monitors the vibration of the drill bit in real time and transmits the vibration data to the machine tool control system. If the vibration amplitude exceeds the preset threshold [V1], the control system automatically reduces the feed speed by 10%, or adjusts the cutting path according to the vibration mode to ensure the straightness and roundness of the drilled hole. After processing, use an internal micrometer to measure the hole diameter and a straightness measuring instrument to check the straightness to ensure that the straightness is within the range of [±A1] and the roundness error does not exceed [B1] mm.

[0031] In the present invention, preferably, the tool setting step is configured with a tool setting strategy, and the tool setting strategy includes

[0032] The image acquisition module acquires the image of the processed hole, and the image recognition module acquires the image of the processed hole and identifies the rough-machined threaded hole and the tool reference point, wherein the tool reference point is specifically the tool starting position in actual processing, identifies the tool cutting edge on the second tap and calculates the tool displacement, wherein the tool displacement is specifically the direction, distance and rotation angle required to move the second tap until the tool cutting edge coincides with the tool reference point.

[0033] Install a high-precision visual sensor on the machine tool workbench so that its field of view can completely cover the tool setting area of ​​the tool and the workpiece. Turn on the visual sensor and the image acquisition and processing system, and obtain clear images of the tool and workpiece by adjusting the focal length, aperture and other parameters of the sensor. Operate the machine tool to slowly move the tool to the vicinity of the tool setting position. The visual sensor collects images and transmits them to the image acquisition and processing system. The system uses a deep learning algorithm to identify the tool cutting edge and the workpiece tool setting reference point, and calculates the deviation value of the tool in the X and Y directions from the ideal tool setting position, such as ΔX = [C1] mm, ΔY = [D1] mm. The machine tool control system automatically controls the tool to move the corresponding distance in the X and Y directions based on the deviation data to complete the tool setting operation. After the tool setting is completed, start the visual sensor again for detection. If the deviation exceeds the range of ± [E1] mm, repeat the above tool setting process until the accuracy requirements are met.

[0034] In the present invention, preferably, the deep hole thread processing method also includes a deviation correction step, and the deviation correction step includes obtaining a floating displacement and a tool holder force value, wherein the floating displacement is specifically a radial floating displacement of the floating processing tool holder during the secondary tapping step, and the tool holder force value is specifically a change trend of the force acting on the floating processing tool holder during the secondary tapping step, and the floating deviation amount is calculated based on the floating displacement and the tool holder force value, and the tool displacement is corrected based on the floating deviation amount.

[0035] In the present invention, preferably, the deep hole thread processing method is configured with a tool state monitoring strategy, and the tool state monitoring strategy is performed when tapping is performed using a floating tool holder. The tool state monitoring strategy includes obtaining the cutting temperature, tool holder vibration, abnormal sound and calculating the tool processing state based on the processing state model. The cutting temperature is specifically the temperature of the tool cutting part, and the tool holder vibration is specifically the vibration amplitude of the tool holder. If an abnormal sound occurs, it reflects an abnormal processing state, and the processing state of the floating processing tool holder is regulated based on the tool processing state.

[0036] In the present invention, preferably, the state control strategy of the floating tool holder includes reducing the feed speed to continue processing and repeatedly collecting the tool vibration amount if the tool vibration amount exceeds the preset vibration amount, processing is performed at the adjusted feed speed if the tool vibration amount can be reduced to the preset vibration amount, and stopping the tool and issuing a tool change prompt if the tool vibration amount cannot be reduced to the preset vibration amount. The vibration sensor monitors the vibration during the processing in real time. If the vibration amplitude exceeds [V2], the control system first tries to reduce the feed speed by 20% to observe whether the vibration is reduced. If the vibration is still not effectively controlled, the vibration reduction device equipped with the machine tool, such as a vibration reduction pad or a vibration damper, is activated to reduce the impact of vibration on the processing accuracy.

[0037] In the present invention, preferably, the state control strategy of the floating tool holder includes collecting the sound signal in the processing process in real time, and transmitting it to the sound analysis module built into the machine tool control system. By comparing and analyzing with the preset normal sound mode, if the sound is judged to be abnormal, an alarm is immediately issued and the machine is shut down. The sound sensor collects the sound signal in the processing process in real time, and transmits it to the sound analysis module built into the machine tool control system. By comparing and analyzing with the preset normal sound mode, if the sound is judged to be abnormal, the system immediately issues an alarm and shuts down, prompting the operator to check whether the tool is worn, damaged or other faults.

[0038] In the present invention, preferably, the state control strategy of the floating tool handle includes a temperature sensor that monitors the tool cutting temperature in real time. When the temperature reaches the warning temperature range, the system issues a warning prompt on the operation interface. When the temperature exceeds the conventional temperature threshold and is less than the warning temperature, the cutting speed is reduced and the cutting fluid flow rate is increased. The tool cutting temperature is repeatedly collected and the temperature drops to a preset safety temperature range. The temperature sensor monitors the tool cutting temperature in real time. When the temperature reaches [Z1-ΔZ1]℃, the system issues a warning prompt on the operation interface to remind the operator to pay close attention to temperature changes. When the temperature exceeds [Z1]℃, the control system automatically reduces the cutting speed to [X2] rpm, and increases the cutting fluid flow rate to [Q1] liters / minute, and continuously monitors the temperature until it drops to a safe range.

[0039] A deep hole thread processing device is provided, which uses any one of the deep hole thread processing methods described above, and the deep hole thread processing device includes a radial floating tool holder.

[0040] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A deep hole thread processing method, characterized in that: The deep hole thread processing method comprises: A tapping step: installing a first tap on the rigid processing tool holder, and performing a first tapping with the rigid processing tool holder to form a rough-processed threaded hole. Tool setting step: installing a second tap on the floating processing tool holder, and aligning the second tap with the rough processing threaded hole. Secondary tapping step: using the floating machining tool holder to perform secondary tapping to form a finish-machined threaded hole, the pitch of the finish-machined hole is consistent with the pitch of the rough-machined threaded hole.

2. A deep hole thread processing method according to claim 1, characterized in that: The tool setting step is configured with a tool setting strategy, and the tool setting strategy includes The image acquisition module acquires the image of the processed hole, and the image recognition module acquires the image of the processed hole and identifies the rough-machined threaded hole and the tool reference point, wherein the tool reference point is specifically the tool starting position in actual processing, identifies the tool cutting edge on the second tap and calculates the tool displacement, wherein the tool displacement is specifically the direction, distance and rotation angle required to move the second tap until the tool cutting edge coincides with the tool reference point.

3. A deep hole thread processing method according to claim 2, characterized in that: The deep hole thread processing method also includes a deviation correction step, which includes obtaining a floating displacement and a tool holder force value. The floating displacement is specifically a radial floating displacement of the floating processing tool holder during the secondary tapping step. The tool holder force value is specifically a change trend of the force acting on the floating processing tool holder during the secondary tapping step. The floating deviation amount is calculated based on the floating displacement and the tool holder force value, and the tool displacement is corrected based on the floating deviation amount.

4. A deep hole thread processing method according to claim 2, characterized in that: The deep hole thread processing method is equipped with a tool state monitoring strategy, which is performed when a floating tool holder is used for tapping. The tool state monitoring strategy includes obtaining the cutting temperature, tool holder vibration, and abnormal sound and calculating the tool processing state based on a processing state model. The cutting temperature is specifically the temperature of the tool cutting part, and the tool holder vibration is specifically the vibration amplitude of the tool holder. If an abnormal sound occurs, it reflects an abnormal processing state. The processing state of the floating processing tool holder is regulated based on the tool processing state.

5. A deep hole thread processing method according to claim 4, characterized in that: The state control strategy of the floating tool holder includes: if the tool vibration exceeds the preset vibration amount, the feed speed is reduced to continue processing and the tool vibration amount is repeatedly collected; if the tool vibration amount can be reduced to the preset vibration amount, processing is performed at the adjusted feed speed; if the tool vibration amount cannot be reduced to the preset vibration amount, the tool is stopped and a tool change prompt is issued.

6. A deep hole thread processing method according to claim 4, characterized in that: The state control strategy of the floating tool holder includes real-time collection of sound signals during the machining process and transmission of the sound signals to the sound analysis module built into the machine tool control system. By comparing and analyzing the sound signals with the preset normal sound pattern, if the sound is judged to be abnormal, an alarm is immediately sounded and the machine is shut down.

7. A deep hole thread processing method according to claim 4, characterized in that: The state control strategy of the floating tool holder includes a temperature sensor that monitors the tool cutting temperature in real time. When the temperature reaches the warning temperature range, the system issues a warning prompt on the operation interface. When the temperature exceeds the conventional temperature threshold and is lower than the warning temperature, the cutting speed is reduced and the cutting fluid flow rate is increased. The tool cutting temperature is repeatedly collected and the temperature drops to a preset safety temperature range.

8. A deep hole thread processing device, using the deep hole thread processing method as described in any one of 1 to 7 above, characterized in that: The deep hole thread processing device comprises a radial floating tool holder.

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