An actively cooled cutting tool based on semiconductor refrigeration and its working method

Abstract

The present invention discloses an active heat dissipation tool based on semiconductor refrigeration and its working method. The active heat dissipation tool includes a tool handle, a tool heat dissipation module, and a cutting edge automatic indexing module; the tool active heat dissipation module includes a heat conduction tube, a semiconductor refrigeration sheet, heat dissipation fins, and a heat dissipation fan. The semiconductor refrigeration sheet, heat dissipation fins, and heat dissipation fan arranged in sequence from inside to outside are installed in the heat release installation area at the tail end of the tool handle. The tool handle is embedded with heat conduction grooves arranged along the length direction of the tool handle. A heat conduction tube is installed in the heat conduction grooves; the refrigerating surface of the semiconductor refrigeration sheet is attached to the heat conduction tube. The cutting edge automatic indexing module includes a multi-edge blade, an electromagnetic tool pad, a pop-up pin, an electromagnetic coil, a fixed pin, and a compression spring. The present invention uses the tool heat dissipation module to reduce the temperature of the turning tool; at the same time, the wear degree of the cutting edge is judged according to the temperature change of the heat exchange medium, and the automatic indexing module of the cutting edge is cooperated to automatically monitor the wear degree of the cutting edge and automatically change the tool when the wear is excessive.

Description

Technical Field

[0001] The present invention belongs to the technical field of turning tool heat dissipation, and particularly relates to an active heat dissipation tool based on semiconductor refrigeration and its working method. Technical Background

[0002] During the turning process, a large amount of cutting heat is generated due to friction and plastic deformation of the workpiece material between the turning tool and the workpiece. Moreover, the cutting heat is concentrated in the cutting area between the tool and the workpiece. The high temperature in the cutting area seriously affects the durability and service life of the tool. The deformation of the workpiece material due to thermal expansion makes it difficult to control the machining accuracy of the workpiece. At the same time, the extensive use of cutting fluid causes many negative impacts. The use of cutting fluid consumes a large amount of resources, and the disposal and recycling increase the processing cost. The many chemical components such as sulfur, phosphorus, chlorine, and hydrocarbons contained in the cutting fluid cause serious environmental pollution. Therefore, accelerating the heat conduction in the cutting area through active heat dissipation to effectively control the influence of cutting temperature on the tool durability, thereby reducing the temperature in the cutting area, is the key to improving the service life of the tool and reducing the use of cutting fluid, and is also the key to improving the machining accuracy of the workpiece and realizing green machining.

[0003] At present, there are few inventions in China for the active heat dissipation of tools, and the method of externally spraying cutting fluid is generally adopted. For example, the invention with the patent number "CN215090751U" discloses a PCD tool heat dissipation device, which cleans the chips remaining on the cutting surface through a gas spraying pipe and a water spraying pipe, and at the same time cools the cutting surface; the invention with the patent number "CN201910964895.3" discloses a vertical milling machine for improving the heat dissipation performance of tools, which sprays coolant through a spraying head to take out the heat of the milling cutter and the chips, thereby achieving efficient heat dissipation; the patent with the patent number "CN201010224871.3" discloses a method for improving the heat dissipation of cutting tools by using heat pipes. This method conducts heat to the heat sink through heat pipes to prevent the temperature of the tool tip from rising. The above inventions use cutting fluid to assist in heat dissipation, but the cutting fluid causes serious environmental pollution, restricting the development of green machining. Moreover, the heat dissipation performance of the device using only heat pipes and heat sinks is relatively low, and it cannot efficiently discharge heat. Therefore, there is an urgent need to design a tool heat dissipation device with high heat dissipation efficiency and significantly reduced or stopped use of cutting fluid to achieve efficient heat dissipation of the tool and green machining. Summary of the Invention

[0004] The present invention aims at the problem that in current turning machining, the turning tool is difficult to dissipate heat actively and the temperature is too high, resulting in aggravated wear of the turning tool, and provides a method and device for active heat dissipation of the tool based on semiconductor refrigeration; the invention is a method for assisting the heat dissipation of the tool based on the semiconductor refrigeration effect; it is a method for realizing the automatic indexing of the multi-edge blade through an electromagnetic automatic telescopic locking mechanism; it is a device for timely transferring heat through a heat conduction pipe; it is a device for real-time monitoring of the temperature change of the turning tool and actively discharging heat according to the temperature of the turning tool; it is an automatic telescopic locking device for automatically indexing and replacing the worn cutting edge of the blade.

[0005] An active heat dissipation tool based on semiconductor refrigeration according to the present invention includes a tool shank, a tool heat dissipation module and a blade automatic indexing module; the blade automatic indexing module is installed at the head end of the tool shank. The tool heat dissipation module is installed at the side part of the tool shank. The tool active heat dissipation module includes a heat conduction pipe, a semiconductor refrigeration chip, heat dissipation fins and a heat dissipation fan. A heat release installation area is arranged at the tail end of the tool shank. The semiconductor refrigeration chip, the heat dissipation fins and the heat dissipation fan arranged in sequence from inside to outside are installed in the heat release installation area. A heat conduction groove is embedded in the tool shank along the length direction of the tool shank. The heat conduction pipe is installed in the heat conduction groove; the refrigerating surface of the semiconductor refrigeration chip is attached to the heat conduction pipe.

[0006] Along the direction from the head end to the tail end of the tool shank, the heat conduction pipe is divided into an evaporation area, a condensation area and a cooling area arranged in sequence. A self-circulating annular flow channel is arranged in the heat conduction pipe. The annular flow channel includes a cooling section, a liquid phase input section, an evaporation section and a condensation reflux section which are connected end to end in sequence to form a ring. The cooling section is arranged in the cooling area; the evaporation section is arranged in the evaporation area. The liquid phase input section and the condensation reflux section are located in the condensation area. The two ends of the liquid phase input section are respectively connected to the bottom parts of the cooling section and the evaporation section. The two ends of the condensation reflux section are respectively connected to the top parts of the cooling section and the evaporation section. The condensation reflux section is arranged obliquely, and the end connected to the evaporation section is higher than the end connected to the cooling section. The annular flow channel is filled with a heat exchange medium. The heat exchange medium does not fill the annular flow channel.

[0007] The blade automatic indexing module includes a multi-edge blade, an electromagnetic tool pad, a pop-up pin, an electromagnetic coil, a fixing pin and a compression spring. The electromagnetic tool pad is fixed at the head end of the tool shank; a guiding hole is opened in the middle of the electromagnetic tool pad. The fixing pin is arranged in the guiding hole and fixed to the electromagnetic tool pad. A pop-up pin sleeve with a central hole is sleeved outside the fixing pin and forms a sliding pair with the guiding hole. A limiting block is arranged at the end of the fixing pin far away from the electromagnetic tool pad. The compression spring is sleeved on the fixing pin, and the two ends respectively abut against the limiting block and the multi-edge blade.

[0008] The electromagnetic tool pad described above is embedded with electromagnetic coils. The ejector pin is arranged inside the electromagnetic coils; when the electromagnetic coils are energized, it drives the ejector pin to slide towards the electromagnetic tool pad. A central hole is provided on the multi-edge blade. The central hole of the multi-edge blade and the fixed pin form a cylindrical pair. The top surface of the multi-edge blade is provided with n cutting edges evenly distributed circumferentially along the central axis of the fixed pin, where n≥2.

[0009] Taking the rotation direction of the tip of the cutting edge of the multi-edge blade towards the inside as the tool change rotation direction. The top of the ejector pin is provided with n triangular first locking teeth evenly distributed circumferentially along the central axis of the fixed pin. The bottom surface of the multi-edge blade is provided with n triangular second locking teeth evenly distributed circumferentially along the central axis of the fixed pin. The first locking teeth and the second locking teeth are corresponding in the radial direction of the fixed pin. The tips of each first locking tooth and the tips of each second locking tooth are respectively staggered; when the ejector pin rises, it will push the multi-edge blade to rise, and drive the multi-edge blade to rotate in the tool change rotation direction through the inclined surfaces on the first locking teeth and the second locking teeth.

[0010] The top surface of the electromagnetic tool pad described above is provided with n guiding and limiting grooves evenly distributed circumferentially along the central axis of the fixed pin. The bottom surface of the multi-edge blade is provided with n guiding and limiting teeth evenly distributed circumferentially along the central axis of the fixed pin. The guiding and limiting grooves and the guiding and limiting teeth are corresponding in the radial direction of the fixed pin. In the initial state, the n guiding and limiting teeth are respectively restricted in the n guiding and limiting grooves.

[0011] Preferably, a temperature sensor is installed at the tail end of the tool handle; the detection part of the temperature sensor extends into the cooling section of the annular flow channel.

[0012] Preferably, heat-conducting paste is filled between the semiconductor refrigeration sheet and the heat dissipation fins, and between the heat dissipation fins and the heat dissipation fan.

[0013] Preferably, the evaporation section is arranged in a serpentine layout.

[0014] Preferably, the heat-conducting tube is made of copper.

[0015] Preferably, a set of heat dissipation pressing pieces is provided at both ends of the tool handle. The four heat dissipation pressing pieces in the same set are respectively fixed to the four side surfaces of the tool handle. Heat-conducting paste is filled between the heat dissipation pressing piece in contact with the heat-conducting tube and the heat-conducting tube. Heat dissipation grooves are provided on the outer side surface of the heat dissipation pressing piece.

[0016] Preferably, a sliding groove is provided on the inner side surface of the guiding hole. The protrusion on the outer side surface of the ejector pin is slidably connected to the sliding groove on the guiding hole.

[0017] Preferably, a permanent magnet is arranged inside the ejector pin or the ejector pin is integrally made of a permanent magnet; and the magnetic pole arrangement direction of the permanent magnet is the axial direction of the ejector pin.

[0018] Preferably, a first guiding surface and a first limiting surface are arranged in the guiding and limiting groove. The first guiding surface is spiral. In the tool changing rotation direction, the first guiding surface gradually moves away from the top surface of the electromagnetic tool pad. The first limiting surface is connected to the end of the first guiding surface away from the top surface of the electromagnetic tool pad. The guiding and limiting teeth are provided with a second guiding surface and a second limiting surface. The shape of the second guiding surface corresponds to that of the first guiding surface. The shape of the second limiting surface corresponds to that of the first limiting surface. When the second guiding surface of a guiding and limiting tooth fits with the first guiding surface of a guiding and limiting groove, the multi-edge blade is guided and rotates spirally along the first guiding surface until the first limiting surface fits with the second limiting surface.

[0019] Preferably, a chamfer is arranged at the connection between the first guiding surface and the top surface of the electromagnetic tool pad.

[0020] The working method of the active heat dissipation tool based on semiconductor refrigeration includes the following steps:

[0021] Step 1: Clamp the active heat dissipation tool on a turning device for cutting.

[0022] Step 2: During the cutting process, the heat exchange medium in the heat conduction tube evaporates and condenses under the drive of the temperature difference, forming a heat exchange cycle, conducting the heat at the head end of the tool shank to the tail end, and dissipating it to the external environment through the semiconductor refrigeration sheet, heat dissipation fins and heat dissipation fan.

[0023] Step 3: When the temperature of the cooling section of the heat conduction tube measured by the temperature sensor is higher than the upper temperature limit value, increase the power of the semiconductor refrigeration sheet and the heat dissipation fan; when the power of the semiconductor refrigeration sheet and the heat dissipation fan reaches the threshold value, if the temperature of the cooling section of the heat conduction tube still cannot be reduced below the upper temperature limit value, it is determined that the cutting edge is excessively worn and the excessively worn cutting edge needs to be replaced.

[0024] The specific process of replacing the cutting edge is as follows:

[0025] ①. Retract the active heat dissipation tool to a safe position.

[0026] ②. The electromagnetic coil in the automatic indexing module is energized, the ejector pin slides outwards, pushes the multi-edge blade to rise, and makes the multi-edge blade rotate unidirectionally.

[0027] ③. The electromagnetic coil is de-energized, the multi-edge blade and the ejector pin slide inwards under the elastic force of the compression spring; the guiding and limiting teeth at the bottom of the multi-edge blade are sequentially guided into the next guiding and limiting groove; during the inward sliding process of the multi-edge blade, it is guided by each guiding and limiting groove and continues to rotate until the first limiting surface on each guiding and limiting tooth contacts the second limiting surface on each guiding and limiting groove; the multi-edge blade rotates 360° / n relative to before replacing the cutting edge.

[0028] The beneficial effects of the present invention are:

[0029] 1. The present invention utilizes a tool heat dissipation module to reduce the temperature of the turning tool; meanwhile, the wear degree of the cutting edge is judged according to the temperature change of the heat exchange medium, and the automatic monitoring of the wear degree of the cutting edge is realized in cooperation with the cutting edge automatic indexing module, and the tool is automatically changed when the wear is excessive.

[0030] 2. The heat dissipation module of the present invention is composed of a semiconductor refrigeration sheet, a heat conduction pipe, heat dissipation fins and a heat dissipation fan, which can timely and efficiently discharge the heat generated during turning processing, thereby reducing or avoiding the use of cutting fluid;

[0031] 3. The cutting edge automatic indexing module in the present invention has an automatically telescopic locking structure driven by electromagnetic force, which can complete the automatic indexing of the multi-edge blade and ensure the stability of the cutting edge during turning processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0033] Figure 2 is a schematic diagram of the internal structure of the heat conduction pipe in the present invention.

[0034] Figure 3 is a schematic diagram of the blade automatic indexing module in the present invention.

[0035] Figure 4 is a cutting edge indexing flow chart of the blade automatic indexing module in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] The present invention will be further described below with reference to the accompanying drawings.

[0037] As Figure 1 shown, an active heat dissipation tool based on semiconductor refrigeration includes a tool heat dissipation module and a cutting edge automatic indexing module; the cutting edge automatic indexing module is installed at the head end of the tool holder 1 for replacing the cutting edge as needed. The tool heat dissipation module is installed on the side of the tool holder 1 for transferring the heat generated during the cutting process.

[0038] The tool active heat dissipation module includes a heat conduction pipe 2, a semiconductor refrigeration sheet 3, heat dissipation fins 4, a heat dissipation fan 5, a heat conduction pressing sheet 6 and a temperature sensor 7. A heat release installation area is provided at the tail end of the tool holder 1. The semiconductor refrigeration sheet 3, the heat dissipation fins 4 and the heat dissipation fan 5 arranged in sequence from inside to outside are installed in the heat release installation area. Thermal paste is filled between the semiconductor refrigeration sheet 3 and the heat dissipation fins 4, and between the heat dissipation fins 4 and the heat dissipation fan 5. The two sides of the semiconductor refrigeration sheet 3 are made of ceramic materials, and the middle is filled with N-type semiconductors and P-type semiconductors arranged alternately. According to the Peltier effect, the temperature is transferred from one side to the other side by the semiconductor refrigeration sheet.

[0039] AsFigure 1 and 2 As shown in 2 , a heat conduction groove is embedded in the tool shank 1 along the length direction of the tool shank 1. One end of the heat conduction groove is close to the cutting edge automatic indexing module at the head end of the tool shank 1; the other end of the heat conduction groove is connected to the heat release installation area at the tail end of the tool shank 1. A heat conduction tube 2 is embedded in the heat conduction groove. Along the direction from the head end to the tail end of the tool shank 1, the heat conduction tube 2 is divided into an evaporation zone, a condensation zone, and a cooling zone arranged in sequence. A self-circulating annular flow channel is provided in the heat conduction tube 2. The annular flow channel includes a cooling section, a liquid-phase input section, an evaporation section, and a condensation return section that are connected end to end in sequence to form a ring. The cooling section is arranged in the cooling zone; the evaporation section is arranged in the evaporation zone and is arranged in a serpentine shape to facilitate increasing the heat exchange area between the evaporation section and the tool. The liquid-phase input section and the condensation return section are located in the condensation zone. The two ends of the liquid-phase input section are respectively connected to the bottoms of the cooling section and the evaporation section. The two ends of the condensation return section are respectively connected to the tops of the cooling section and the evaporation section. The condensation return section is inclined, and the end connected to the evaporation section is higher than the end connected to the cooling section. The annular flow channel is filled with a heat exchange medium. The heat exchange medium does not fill the annular flow channel, so that the top area of the annular flow channel (i.e., the condensation return section) can provide space for the gasification of the heat exchange medium, enabling the heat exchange medium to automatically form a cycle in the annular flow channel.

[0040] The material of the heat conduction tube 2 is copper; during the turning process, the cutting edge on the cutting edge automatic indexing module cuts the workpiece, generating heat. The heat exchange medium in the evaporation section is heated and evaporated, taking away heat. The steam moves from the condensation return section to the cooling section and is gradually cooled, condensing into a liquid and releasing latent heat at the same time; the liquid flows back to the cooling section along the condensation return section; the refrigerating surface of the thermoelectric cooler 3 is attached to the heat conduction tube 2, absorbing the heat of the heat exchange medium in the cooling section. The heat dissipation surface of the thermoelectric cooler 3 transfers the heat to the heat dissipation fins 4, and the heat is dissipated to the external environment by the cooling fan 5. The heat exchange medium with reduced temperature flows to the evaporation section again through the liquid-phase input section; thus, a heat conduction closed cycle is completed. Thereby, continuous cooling of the turning tool can be achieved without relying on cutting fluid.

[0041] A temperature sensor is installed at the tail end of the tool shank 1; the detection part of the temperature sensor extends into the cooling section of the annular flow channel for real-time monitoring of the temperature of the heat exchange medium in the cooling section. When the temperature of the heat exchange medium in the cooling section is too high, it indicates insufficient heat dissipation power or excessive wear of the cutting edge of the turning tool, and thus the power adjustment of the cooling fan 5 and the cutting edge switching control are carried out.

[0042] A set of heat dissipation pressing pieces 6 are provided at both ends of the tool shank 1. The four heat dissipation pressing pieces 6 in the same group are respectively fixed to the four side surfaces of the tool shank 1 by bolts. A heat conduction paste is filled between the heat dissipation pressing piece 6 in contact with the heat conduction tube 2 and the heat conduction tube 2 to achieve efficient heat conduction. Heat dissipation grooves are provided on the outer side surface of the heat conduction pressing piece 6.

[0043] When the turning tool generates cutting heat, a temperature gradient will be generated on the tool shank 1, resulting in heat transfer. The amount of heat transferred by the tool shank per unit time is Its expression is as follows:

[0044]

[0045] where λ is the thermal conductivity of the material of the tool shank 1, which is mainly related to the material type and composition, temperature, and structure.

[0046] When the heat transfer medium flows to the hot end, forced convection heat transfer occurs, and its heat transfer process follows Newton's cooling law:

[0047] q = h(T s - T B )

[0048] where q is the heat flux density flowing out of the normal surface of the contact surface between the tool shank 1 and the heat transfer medium, h is the convective heat transfer coefficient, and T s , T B are the temperature of the tool shank 1 and the temperature of the heat transfer medium, respectively.

[0049] The downward pressure type cooling fan 5 installed outside the heat dissipation fin 4 can timely dissipate the heat on the surface of the heat dissipation fin 4. The two sides of the semiconductor heat sink 3 are made of ceramic materials, and the middle is filled with N-type semiconductors and P-type semiconductors arranged alternately. According to the Peltier effect, the temperature is transferred from one side to the other by the thermoelectric cooler.

[0050] In the present invention, the thermoelectric cooling effect is mainly affected by the working current and the material. The optimal current I maxη when the cooling efficiency η is at an extreme value is:

[0051]

[0052] The maximum cooling efficiency η max is:

[0053]

[0054] where T m is the arithmetic mean of the cold end temperature T c and the hot end temperature T h ; α AB is the thermoelectric power (Seebeck coefficient) of the thermoelectric cooler 3; Z is the figure of merit coefficient of the N-type and P-type semiconductor materials, where ΔT is the temperature difference between the cold and hot ends, K is the total thermal conductivity of the conductor, and R is the total resistance of the thermoelectric cooler 3.

[0055] Such as Figure 2As shown, the blade automatic indexing module includes a multi-edge blade 8, an electromagnetic tool pad 9, a ejector pin 10, an electromagnetic coil 11, a fixing pin, and a compression spring 13. The electromagnetic tool pad 9 is fixed to the head end of the tool shank; a guiding hole with a vertically arranged axis is formed in the middle of the electromagnetic tool pad 9. The fixing pin is coaxially arranged in the guiding hole and is fixed to the electromagnetic tool pad 9. A sliding groove is arranged on the inner side surface of the guiding hole. The central hole of the ejector pin 10 is sleeved outside the fixing pin. The ejector pin 10 is slidably connected in the guiding hole, and the sliding groove in the guiding hole realizes circumferential limitation. A limiting block is arranged at the end of the fixing pin away from the electromagnetic tool pad 9. The compression spring 13 is sleeved on the fixing pin, and both ends respectively abut against the limiting block and the multi-edge blade 8.

[0056] The electromagnetic tool pad 9 is embedded with an electromagnetic coil 11. The electromagnetic coil 11 is specifically fixed in the cavity inside the electromagnetic tool pad 9 by means of bonding. The ejector pin 10 is arranged inside the electromagnetic coil 11; a permanent magnet is arranged inside the ejector pin 10 or the ejector pin 10 is integrally made of a permanent magnet; and the magnetic pole arrangement direction of the permanent magnet is the axial direction of the ejector pin 10. When the electromagnetic coil 11 is energized in the forward direction, the ejector pin 10 will pop up upward due to Lenz's law, pushing the multi-edge blade 8 to rise against the elastic force of the compression spring 13.

[0057] A central hole is formed in the multi-edge blade 8. The central hole of the multi-edge blade 8 and the fixing pin form a cylindrical pair. The top surface of the multi-edge blade 8 is square, and cutting edges are arranged at the four corners of its top surface; every time the multi-edge blade 8 rotates 90°, the cutting edge for machining can be switched.

[0058] Taking the rotation direction from the tip (i.e., the outer end) to the inside (the inner end) of the cutting edge of the multi-edge blade 8 as the tool change rotation direction. Four triangular first locking teeth evenly distributed circumferentially along the central axis of the fixing pin are arranged at the top of the ejector pin 10. Four triangular second locking teeth evenly distributed circumferentially along the central axis of the fixing pin are arranged at the bottom surface of the multi-edge blade 8. The first locking teeth and the second locking teeth are in corresponding positions in the radial direction of the fixing pin. The tips of each first locking tooth and the tips of each second locking tooth are respectively staggered; the tip of the first locking tooth is located on the side away from the tool change rotation direction of the tip of its closest second locking tooth. When the ejector pin 10 rises, it will push the multi-edge blade 8 to rise, and drive the multi-edge blade 8 to rotate a preset angle θ in the tool change rotation direction through the inclined surfaces on the first locking teeth and the second locking teeth (after rotation, each first locking tooth is stuck into the recess between two adjacent second locking teeth, so as to maintain stability).

[0059] Four guiding and limiting grooves evenly distributed circumferentially along the central axis of the fixing pin are formed on the top surface of the electromagnetic tool pad 9. Four guiding and limiting teeth evenly distributed circumferentially along the central axis of the fixing pin are arranged at the bottom surface of the multi-edge blade 8. The guiding and limiting grooves and the guiding and limiting teeth are in corresponding positions in the radial direction of the fixing pin.

[0060] The guiding and limiting groove is provided with a first guiding surface and a first limiting surface. The first guiding surface is spiral. The first limiting surface is a plane and is within the axial section of the fixing pin. In the tool-changing rotation direction, the first guiding surface gradually moves away from the top surface of the electromagnetic tool pad 9. The first limiting surface is connected to the position where the first guiding surface moves away from the top surface of the electromagnetic tool pad 9.

[0061] The four guiding and limiting teeth are provided with a second guiding surface and a second limiting surface. The shape of the second guiding surface corresponds to that of the first guiding surface. The shape of the second limiting surface corresponds to that of the first limiting surface. When the second guiding surface of a guiding and limiting tooth fits with the first guiding surface on a guiding and limiting groove, the multi-edge cutting blade 8 is guided and rotates spirally in the tool-changing rotation direction until the first limiting surface fits with the second limiting surface. During the turning process, the cutting force received by the multi-edge cutting blade 8 causes the first limiting surface and the second limiting surface to fit tightly, and the first guiding surface and the second guiding surface to fit tightly. Therefore, the multi-edge cutting blade 8 with the function of switching cutting edges can remain stable during turning processing.

[0062] In each guiding and limiting groove, the angle of the gap between two adjacent guiding and limiting grooves (i.e., the gap between the first limiting surface of the previous guiding and limiting groove and the first guiding surface of the next guiding and limiting groove) relative to the central axis of the fixing pin is less than θ, so that after the multi-edge cutting blade 8 is lifted by the ejecting pin 10, each guiding and limiting tooth can be guided into the next guiding and limiting groove, realizing the switching of the cutting edges on the multi-edge cutting blade 8.

[0063] As a non-essential preferred solution, a chamfer is provided at the connection between the first guiding surface and the top surface of the electromagnetic tool pad 9, so that when the ejecting pin 10 pushes up the multi-edge cutting blade 8, the multi-edge cutting blade 8 can rotate in time, avoiding a large-amplitude sudden rotation state of the multi-edge cutting blade 8.

[0064] The working method of the active heat dissipation tool based on semiconductor refrigeration includes the following steps:

[0065] Step 1: When the lathe starts cutting processing, the multi-edge cutting blade 8 comes into contact with the workpiece, and at the same time, a large amount of cutting heat is generated, and the heat is transferred to the evaporation area of the heat conduction tube 2.

[0066] Step 2: The heat exchange medium in the heat conduction tube 2 installed in the tool holder 1 evaporates and condenses under the drive of the temperature difference and circulates, and timely conducts the heat at the tool tip of the tool holder 1 to the tail end of the tool holder 1.

[0067] Step 3: The heat conduction tube 2 transfers the heat to the refrigerating surface of the semiconductor refrigeration chip 3. After the semiconductor refrigeration chip 3 is powered on, the refrigerating surface of the refrigeration chip 3 starts to transfer the heat to the heat dissipation surface.

[0068] Step Four: The heat dissipation surface of the semiconductor refrigeration sheet 3 transfers heat to the heat dissipation fins 4 in a timely manner. The heat dissipation fins 4 have a large surface area, which speeds up the heat dissipation rate. At the same time, the cooling fan 5 blows high-speed flowing air towards the heat dissipation fins 4 to take away the generated heat in a timely manner, thus completing a heat dissipation cycle.

[0069] Step Five: After the cutting edge for turning processing is worn, the cutting temperature will increase abnormally, causing the temperature of the heat transfer medium in the cooling section of the heat exchange tube 2 to increase abnormally accordingly. When the cooling fan 5 is adjusted to the maximum power, if the temperature value measured by the temperature sensor is still higher than the threshold, it is necessary to replace the overly worn cutting edge. The specific process of replacing the cutting edge is as follows:

[0070] ①. Retract the tool to a safe position.

[0071] ②. The electromagnetic coil 11 in the automatic indexing module passes through an instantaneous high-voltage current. The ejector pin 10 is ejected upward under the action of Lenz's law. The ejector pin 10 moves upward through the guide groove of the electromagnetic tool pad 9. The first teeth on the ejector pin 10 abut against the second teeth at the bottom of the multi-edge blade 8, pushing the multi-edge blade 8 to rise. Since the second teeth of the multi-edge blade 8 are offset from the first teeth of the ejector pin 10 by a certain angle, when the blade 8 is pressed downward by the compression spring 13, it rotates unidirectionally.

[0072] ③. The electromagnetic coil 11 is powered off, and the multi-edge blade 8 and the ejector pin 10 fall back under the elastic force of the compression spring 13. Since the multi-edge blade 8 rotates when it rises, the guiding and limiting teeth at the bottom of the multi-edge blade 8 are sequentially guided into the next guiding and limiting groove one by one. During the downward sliding process of the multi-edge blade 8, it continues to rotate under the guidance of each guiding and limiting groove until the first limiting surface on each guiding and limiting tooth contacts the second limiting surface on each guiding and limiting groove. The multi-edge blade 8 rotates 90° relative to before tool change, completing the replacement of the cutting edge for processing.

Claims

1. An active heat dissipation tool based on semiconductor refrigeration, characterized in that: it includes a tool handle (1), a tool heat dissipation module and a cutting edge automatic indexing module; the cutting edge automatic indexing module is installed at the head end of the tool handle (1); the tool heat dissipation module is installed at the side of the tool handle (1); the tool heat dissipation module includes a heat conduction tube (2), a semiconductor refrigeration sheet (3), heat dissipation fins (4) and a heat dissipation fan (5); a heat release installation area is arranged at the tail end of the tool handle (1); the semiconductor refrigeration sheet (3), heat dissipation fins (4) and heat dissipation fan (5) arranged in sequence from inside to outside are installed in the heat release installation area; a heat conduction groove is embedded in the tool handle (1) along the length direction of the tool handle (1); the heat conduction tube (2) is installed in the heat conduction groove; the refrigerating surface of the semiconductor refrigeration sheet (3) is attached to the heat conduction tube (2); along the direction from the head end to the tail end of the tool handle (1), the heat conduction tube (2) is divided into an evaporation area, a condensation area and a cooling area arranged in sequence; a self-circulating annular flow channel is arranged in the heat conduction tube (2); the annular flow channel includes a cooling section, a liquid phase input section, an evaporation section and a condensation reflux section that are connected end to end in sequence to form a ring; the cooling section is arranged in the cooling area; the evaporation section is arranged in the evaporation area; the liquid phase input section and the condensation reflux section are located in the condensation area; both ends of the liquid phase input section are respectively connected to the bottoms of the cooling section and the evaporation section; both ends of the condensation reflux section are respectively connected to the tops of the cooling section and the evaporation section; the condensation reflux section is arranged obliquely, and the end connected to the evaporation section is higher than the end connected to the cooling section; a heat exchange medium is filled in the annular flow channel; the heat exchange medium does not fill the annular flow channel; the cutting edge automatic indexing module includes a multi-edge blade (8), an electromagnetic knife pad (9), a ejector pin (10), an electromagnetic coil (11), a fixing pin and a compression spring (13); the electromagnetic knife pad (9) is fixed at the head end of the tool handle; a guiding hole is opened in the middle of the electromagnetic knife pad (9); the fixing pin is arranged in the guiding hole and fixed to the electromagnetic knife pad (9); the ejector pin (10) with a central hole is sleeved outside the fixing pin and forms a sliding pair with the guiding hole; a limiting block is arranged at the end of the fixing pin away from the electromagnetic knife pad (9); the compression spring (13) is sleeved on the fixing pin, and both ends respectively abut against the limiting block and the multi-edge blade (8); the electromagnetic coil (11) is embedded in the electromagnetic knife pad (9); the ejector pin (10) is arranged inside the electromagnetic coil (11); when the electromagnetic coil (11) is electrified, it drives the ejector pin (10) to slide towards the electromagnetic knife pad (9); a central hole is opened in the multi-edge blade (8); the central hole of the multi-edge blade (8) forms a cylindrical pair with the fixing pin; n cutting edges evenly distributed in the circumferential direction along the central axis of the fixing pin are arranged on the top surface of the multi-edge blade (8), and n≥2; The tool change rotation direction is the rotation direction with the tip of the cutting edge of the multi-edge blade (8) facing inward; the top of the ejector pin (10) is provided with n triangular first locking teeth evenly distributed circumferentially along the central axis of the fixed pin; the bottom surface of the multi-edge blade (8) is provided with n triangular second locking teeth evenly distributed circumferentially along the central axis of the fixed pin; the first locking teeth and the second locking teeth are corresponding in the radial direction of the fixed pin; the tips of the first locking teeth and the tips of the second locking teeth are respectively offset; when the ejector pin (10) rises, it will push the multi-edge blade (8) to rise, and drive the multi-edge blade (8) to rotate in the tool change rotation direction through the inclined surfaces on the first locking teeth and the second locking teeth; The top surface of the electromagnetic tool pad (9) is provided with n guiding and limiting grooves evenly distributed circumferentially along the central axis of the fixed pin; the bottom surface of the multi-edge blade (8) is provided with n guiding and limiting teeth evenly distributed circumferentially along the central axis of the fixed pin; the guiding and limiting grooves and the guiding and limiting teeth are corresponding in the radial direction of the fixed pin; in the initial state, the n guiding and limiting teeth are respectively restricted in the n guiding and limiting grooves; A temperature sensor is installed at the tail end of the tool shank (1); the detection part of the temperature sensor extends into the cooling section of the annular flow channel.

2. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: Thermal conductive paste is filled between the semi-conductor refrigeration sheet (3) and the heat dissipation fins (4), and between the heat dissipation fins (4) and the heat dissipation fan (5).

3. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: The evaporation section is arranged in a serpentine layout.

4. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: The material of the heat conduction tube (2) is copper.

5. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: A set of heat dissipation pressing sheets (6) are arranged at both ends of the tool shank (1); the four heat dissipation pressing sheets (6) in the same group are respectively fixed to the four side surfaces of the tool shank (1); thermal conductive paste is filled between the heat dissipation pressing sheet (6) in contact with the heat conduction tube (2) and the heat conduction tube (2); heat dissipation grooves are provided on the outer side surface of the heat dissipation pressing sheet (6).

6. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: A sliding groove is provided on the inner side surface of the guiding hole; the protrusion on the outer side surface of the ejector pin (10) is slidably connected to the sliding groove on the guiding hole.

7. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: A permanent magnet is arranged inside the ejector pin (10) or the ejector pin (10) is integrally made of a permanent magnet; and the magnetic pole arrangement direction of the permanent magnet is the axial direction of the ejector pin (10).

8. A semi-conductor refrigeration-based active heat dissipation tool according to claim 1, characterized in that: A first guiding surface and a first limiting surface are arranged in the guiding and limiting groove; the first guiding surface is spiral; in the tool changing rotation direction, the first guiding surface gradually moves away from the top surface of the electromagnetic tool pad (9); the first limiting surface is connected to the end of the first guiding surface away from the top surface of the electromagnetic tool pad (9); a second guiding surface and a second limiting surface are arranged on the guiding and limiting teeth; the shape of the second guiding surface corresponds to that of the first guiding surface; the shape of the second limiting surface corresponds to that of the first limiting surface; when the second guiding surface of a guiding and limiting tooth fits with the first guiding surface of a guiding and limiting groove, the multi-edge blade (8) is guided and rotates spirally along the first guiding surface until the first limiting surface fits with the second limiting surface.

9. The working method of an actively cooled tool based on semiconductor refrigeration according to claim 1, characterized in that: it includes the following steps: Step 1: Clamp the actively cooled tool on a turning device for cutting. Step 2: During cutting, the heat exchange medium in the heat conduction tube (2) evaporates and condenses under the drive of the temperature difference to form a heat exchange cycle, conducts the heat at the head end of the tool shank (1) to the tail end, and dissipates it to the external environment through the semiconductor refrigeration sheet (3), the heat dissipation fins (4) and the heat dissipation fan (5). Step 3: When the temperature of the cooling section of the heat conduction tube (2) measured by the temperature sensor is higher than the upper temperature limit value, increase the power of the semiconductor refrigeration sheet (3) and the heat dissipation fan (5); when the power of the semiconductor refrigeration sheet (3) and the heat dissipation fan (5) reaches the threshold value, if the temperature of the cooling section of the heat conduction tube (2) still cannot be reduced below the upper temperature limit value, it is determined that the cutting edge is excessively worn and the excessively worn cutting edge needs to be replaced. The specific process of replacing the cutting edge is as follows: ①. Retract the actively cooled tool to a safe position. ②. The electromagnetic coil (11) in the automatic indexing module is energized, the ejector pin (10) slides outwards, pushes the multi-edge blade (8) to rise, and causes the multi-edge blade (8) to rotate unidirectionally. ③. The electromagnetic coil (11) is de-energized, the multi-edge blade (8) and the ejector pin (10) slide inwards under the elastic force of the compression spring (13); each guiding and limiting tooth at the bottom of the multi-edge blade (8) is sequentially guided into the next guiding and limiting groove; during the inward sliding process of the multi-edge blade (8), it is guided by each guiding and limiting groove and continues to rotate until the first limiting surface on each guiding and limiting tooth contacts the second limiting surface on each guiding and limiting groove; the multi-edge blade (8) rotates 360° / n relative to before replacing the cutting edge.

Images