Full-closed-loop control high-precision feeding transmission mechanism for numerical control machine tool

Abstract

The invention discloses a full-closed-loop control high-precision feeding transmission mechanism for a numerical control machine tool, which belongs to the technical field of numerical control machine tools, and comprises a linear execution component, and the linear execution component comprises a slide rail structure and a ball screw pair structure; the ball screw pair structurally comprises a ball screw nut, and a motion restraining and resistance increasing unit is arranged on the side wall of the ball screw nut. By means of the movement restraining and resistance increasing unit which is installed on the side wall of the ball screw nut and elastically abuts against the sliding rail structure, friction damping continuously exists in the movement process of the ball screw nut, and therefore the friction damping can be continuously generated at the moment that the servo motor is shut down. Inertial kinetic energy generated by the ball screw nut at the moment that a servo motor is shut down is effectively restrained through friction damping, and the situation that due to long-term use of a ball screw nut transmission pair structure in a numerical control machine tool feeding transmission mechanism, a lead screw, the nut and a ball are greatly abraded is avoided, and the service life of the lead screw is prolonged. Therefore, when the feeding transmission mechanism is shut down, the feeding transmission mechanism is subjected to positioning deviation due to the inertia effect and exceeds the target position.

Description

Technical Field

[0001] This invention relates to the field of CNC machine tool technology, and more specifically, to a high-precision feed transmission mechanism for fully closed-loop control of CNC machine tools. Background Technology

[0002] With the advancement of technology, CNC machine tool technology has developed rapidly. The feed transmission mechanism of CNC machine tools is often implemented using a servo feed system. The servo feed system has multiple interfaces that can realize full closed-loop control. Its full closed-loop control involves centralizing the signals from multiple interfaces onto a single chip for processing, and using a certain coordination mechanism to manage the cooperation of each interface to achieve the full closed-loop control function.

[0003] The function of the servo feed system is to amplify the command information issued by the CNC system and control the movement of the actuator. It not only controls the speed of the feed system, but also precisely controls the movement trajectory and coordinate position of the tool relative to the workpiece.

[0004] The current CNC and industrial control fields employ a wide variety of position sensors with increasingly diverse interfaces and communication methods, while the requirements for semi-closed-loop and fully closed-loop control are constantly rising. Existing position information processing devices have limited functionality and are insufficient to fully meet the needs of CNC and industrial control fields.

[0005] A cutting tool is a machine tool accessory that is mounted on a CNC machine tool and connected to the spindle to drive the tool to rotate. It is a major component of machine tool equipment. The high-speed feed transmission mechanism enables the tool to move up and down rapidly to complete the feed work in the machining process.

[0006] Currently, the feed servo system of CNC machine tools mainly uses a ball screw and nut transmission pair structure to convert high-speed rotary motion into linear motion of the grinding head. It has advantages such as low friction loss, high transmission efficiency, smooth motion, and high transmission rigidity.

[0007] During long-term use, the feed transmission mechanism of CNC machine tools experiences significant wear between the screw, nut, and balls in the ball screw and nut transmission pair, leading to axial movement. When the machine stops, the wear clearance between the screw, nut, and balls can easily cause positioning offset displacement due to inertia, thus exceeding the target position and affecting the positioning accuracy of the CNC machine tool's feed transmission mechanism during operation.

[0008] In view of this, we propose a high-precision feed transmission mechanism with fully closed-loop control for CNC machine tools. Summary of the Invention

[0009] Technical problem to be solved: The purpose of this invention is to provide a high-precision feed transmission mechanism with full closed-loop control for CNC machine tools, which solves the technical problems mentioned in the background art.

[0010] Technical solution: The technical solution of the present invention provides a high-precision feed transmission mechanism for CNC machine tools with full closed-loop control, including a linear actuator and a servo motor. The linear actuator includes a slide rail structure and a ball screw pair structure. The ball screw assembly structure includes a ball screw nut, and a damping and resistance increasing unit is provided on the side wall of the ball screw nut; The damping and resistance increasing unit includes a retractable linear telescopic component. The free end of the linear telescopic component is provided with several anti-slip pads arranged in a stacked state. The fixed end of the linear telescopic component is provided with a first alarm and a second alarm respectively. The inner cavity of the linear telescopic component is provided with an elastic mechanism that can be elastically extended. The elastic mechanism includes a spring-back component and a retractable retractable component; The recessed component includes an opening and closing module disposed within its internal cavity; The opening and closing module includes a moving terminal module disposed on the free end of the retracted part and a fixed terminal module disposed on the fixed end of the retracted part, wherein the free end of the fixed terminal module abuts against the surface of the moving terminal module. The moving terminal module includes a first trigger terminal piece, a second trigger terminal piece, and a support member; During the synchronous extension and retraction of the retractable component in the elastic mechanism following the linear telescopic assembly, when the fixed terminal module contacts the first trigger terminal piece, the second alarm is triggered to open. After the springback component in the elastic mechanism returns to its initial relaxed state, the retractor is in its initial extended state. At this time, when the moving terminal module contacts the second trigger terminal piece, the first alarm is triggered to open.

[0011] As an optional solution to the technical solution of this invention, the slide rail structure includes a processing stand, and two guide rails are symmetrically connected in the inner cavity of the processing stand. Each guide rail is slidably fitted with a movable sleeve, and the two movable sleeves are connected to a common feed frame, on which a milling head for milling the workpiece is installed; The ball screw assembly structure also includes a screw located in the inner cavity of the machining stand and between two guide rails, with the two ends of the screw rotatably connected to the top and bottom walls of the inner cavity of the machining stand, respectively. The ball screw nut is threaded onto the screw; The servo motor is connected to the top of the machining stand, and the output shaft of the servo motor is connected to the end of the lead screw.

[0012] As an optional solution of the technical solution in this invention document, the linear telescopic assembly includes a base box whose end is connected to the side wall of the ball screw nut. A U-shaped base is slidably inserted into the opening at the end of the base box away from the ball screw nut, and several anti-slip pads in a stacked state are connected to the end of the U-shaped base away from the base box. Both the first and second alarms are fixedly installed on the base box.

[0013] As an optional solution to the technical solution of this invention, the recessed component includes a heat-inducing cylinder seat; An insulating advance / retreat rod is slidably inserted into one end of the heat-inducing cylinder base.

[0014] As an optional solution to the technical solution of this invention, the fixed terminal module includes a terminal contact spring; The fixed end of the contact spring is connected to the side wall of one end of the insulating advance and retreat rod that extends into the inner cavity of the heat-conducting cylinder seat.

[0015] As an optional solution to the technical solution of this invention, the moving terminal module includes an insulating guide groove, and a first trigger end piece and a second trigger end piece are respectively connected to the bottom wall of the inner cavity of the insulating guide groove. The top surfaces of both the first and second trigger terminals are flush with the bottom wall of the inner cavity of the insulating guide groove. The free end of the end contact spring extends into the inner cavity of the insulating guide groove and elastically abuts against the bottom wall of the inner cavity of the insulating guide groove. When the spring is in the initial relaxed state, the second trigger end piece is located between the end contact spring and the first trigger end piece.

[0016] As an optional solution to the technical solution of this invention document, the support component includes a forced piston, and a plurality of insulated driven cylinders are inserted and fixed on the forced piston; One end of the insulating driven cylinder passes through the forced piston and is slidably inserted with an insulating push rod, and a return spring is fitted over the insulating push rod. Each of the several insulating driven cylinders has a first switch terminal and a second switch terminal arranged opposite to each other in its inner cavity, and one end of an insulating rod corresponding to the insulating driven cylinder extends into the inner cavity of the insulating driven cylinder and is connected to the second switch terminal. One end of the first switch terminal is connected to a heat-drawing spring, and the end of the heat-drawing spring away from the first switch terminal is connected to the end of the inner cavity of the insulating driven cylinder. The supporting components also include a liquid phase limiting layer.

[0017] As an optional solution to the technical solution of this invention, an inner cavity is provided inside the wall of the heat-generating cylinder seat at a position corresponding to the position of the insulating guide groove; The forced piston seal slides within the inner cavity; A liquid-phase limiting layer fills the inner cavity; The end of the insulating driven cylinder away from the insulating push rod is sealed and passes through the end of the inner cavity and extends into the inner cavity of the heat-conducting cylinder seat to connect with the insulating guide groove; The end of the insulating rod away from the insulating driven cylinder is connected to the end of the inner cavity; One end of the return spring is connected to the end of the insulated driven cylinder, and the other end is connected to the end of the inner cavity. The liquid phase limiting layer is located on the side of the forced piston near the insulating guide groove; A vent is also provided on the side wall of the heat-generating cylinder seat at a position corresponding to the inner cavity, which is connected to the end of the inner cavity away from the insulating guide groove.

[0018] As an optional solution of the technical solution in this invention document, the rebound member includes a pressure-sensing spring sleeved on the outer periphery of the retracted member, both ends of the pressure-sensing spring are connected to heat-conducting seats, and the opposite ends of the two heat-conducting seats are connected to heat-insulating bases. One of the heat-insulating bases is connected to the end of the inner cavity of the U-shaped base, and the other heat-insulating base is connected to the end of the inner cavity of the base tube. One of the heat-conducting seats is connected to the end of the heat-initiating cylinder seat, and the other heat-conducting seat is connected to the end of the insulating advance and retreat bar. The heat-conducting seat connected to the end of the heat-initiating cylinder seat has an electric heating element inside its wall.

[0019] As an optional solution of the technical solution in this invention document, when the spring is in the initial relaxed state, the pressure-sensing spring is in the initial relaxed state, and at this time, the end contact spring, the second trigger end piece, and the first trigger end piece do not contact each other. When the first switch terminal comes into contact with the second switch terminal, the series circuit consisting of the first switch terminal, the second switch terminal, the electric heating element, and the third alarm is turned on.

[0020] Beneficial effects: One or more technical solutions provided in this invention have at least the following technical effects or advantages: 1. By driving the ball screw in the ball screw pair structure to rotate via a servo motor, the ball screw nut drives the milling head mounted on the feed carriage to move up and down to achieve the feed action. During this process, the damping and resistance-increasing unit installed on the side wall of the ball screw nut and elastically abutting against the slide rail structure provides continuous frictional damping during the movement of the ball screw nut. This effectively suppresses the inertial kinetic energy generated by the ball screw nut when the servo motor stops, preventing significant wear between the screw, nut, and balls in the CNC machine tool feed transmission mechanism due to long-term use. This avoids positioning deviations caused by inertia when the feed transmission mechanism stops, thus improving the positioning accuracy of the CNC machine tool feed transmission mechanism during operation.

[0021] 2. Before installing the damping and resistance-increasing unit on the side wall surface of the ball screw nut, first place the damping and resistance-increasing unit between the guide rail and the ball screw nut. The retracting linear telescopic component compresses the spring piece, and when the retraction amount of the linear telescopic component reaches the preset range, the first trigger end piece contacts the end contact spring piece and triggers the second alarm to open, alerting the operator. At this time, when the pressure of the damping and resistance-increasing unit on the surface of the guide rail has reached the preset range value, the frictional damping experienced by the ball screw nut during its movement is within the preset range. This enables the monitoring and sensing of the frictional damping experienced by the ball screw nut during its movement, thereby effectively preventing the ball screw nut from being inaccurately positioned due to insufficient frictional resistance caused by inertial kinetic energy at the moment the servo motor stops.

[0022] 3. Remove the damping and resistance-increasing unit from the ball screw nut and perform regular maintenance. When the pressure-sensing spring in the telescopic component is subjected to prolonged pressure, and its elastic force weakens due to fatigue, the travel distance of the end contact spring will shorten when it returns and contacts the second trigger end piece. This will trigger the first alarm to issue a fault warning signal, reminding the staff to replace or repair the pressure-sensing spring in the faulty damping and resistance-increasing unit in a timely manner. This will prevent the frictional damping experienced by the ball screw nut during its movement from decreasing due to the weakening of the pressure-sensing spring's elastic force, and will help to further improve the positioning accuracy of the CNC machine tool's feed transmission mechanism.

[0023] 4. When the contact spring in the moving terminal module comes into contact with the first trigger terminal or the second trigger terminal in the fixed terminal module, the heat generated is continuously conducted through the insulating driven cylinder to the liquid phase limiting layer, and then the liquid phase limiting layer dissipates heat and cools it, so that the above-mentioned "terminal" can be maintained within a suitable temperature range, thereby improving the reliability and stability of the operation of the damping and resistance increasing unit.

[0024] 5. During the cold season, when the liquid phase limiting layer in the damping and resistance increasing unit, which was originally in a liquid state, freezes into ice due to the low temperature, its volume increases and drives the first switch terminal to contact the second switch terminal through the forced piston. At the same time, the third alarm and the electric heating element are triggered. The activated third alarm reminds the operator that the liquid phase limiting layer has turned into a frozen state and the operation of the feed transmission mechanism needs to be stopped.

[0025] 6. The heat generated by the electric heating element is transferred to the heat-conducting cylinder seat through the heat-conducting seat. After the solidified liquid phase limiting layer melts into a liquid state, the first switch terminal and the second switch terminal lose contact. During the process of the liquid phase limiting layer melting into a liquid state, under the elastic force of the return spring, the driven piston drives the insulating guide groove through the insulating driven cylinder, so that the end contact spring is tightly pressed against the bottom wall surface of the inner cavity of the insulating guide groove again. This avoids the liquid phase limiting layer from solidifying due to low ambient temperature, which would cause the driven piston to move while the insulating driven cylinder drives the insulating guide groove to move away from the end contact spring. This would result in poor contact or even separation between the end contact spring and the first or second trigger end piece, which would seriously affect the accuracy and reliability of monitoring and sensing the frictional damping of the ball screw nut during its movement. This enables fault self-correction, allowing the feed transmission mechanism to quickly return to normal operation, and also helps to ensure the positioning accuracy of the CNC machine tool feed transmission mechanism. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0027] Figure 2 For the present invention Figure 1 A magnified view of part A in the diagram.

[0028] Figure 3 This is a top view of the overall structure of the present invention.

[0029] Figure 4 For the present invention Figure 3 A magnified view of part B in the diagram.

[0030] Figure 5 For the present invention Figure 4 A magnified view of part C in the middle.

[0031] Figure 6 This is a bottom view of the overall structure of the present invention.

[0032] Figure 7 For the present invention Figure 6 A magnified view of part D in the middle.

[0033] Figure 8 This is a cross-sectional view of the damping and resistance-increasing unit in this invention.

[0034] Figure 9 For the present invention Figure 8 A magnified view of part E in the middle.

[0035] Figure 10 For the present invention Figure 8 A magnified view of part F in the middle section.

[0036] Figure 11This is a schematic diagram of the internal structure of the insulating driven cylinder in this invention.

[0037] Explanation of the labels in the diagram: 101. Machining stand; 102. Servo motor; 103. Guide rail; 104. Feed frame; 105. Movable sleeve; 106. Lead screw; 107. Ball screw nut; 201. Base box; 202. U-shaped base; 203. First alarm; 204. Second alarm; 205. Heat-conducting base; 207. Electric heating element; 208. Pressure-sensing spring; 209. Insulated advance / retreat rod; 210. Heat-inducing cylinder base; 213. Insulated guide groove; 214. First trigger end piece; 215. Second trigger end piece; 216. Liquid phase limiting layer; 217. Insulated driven cylinder; 218. Forced piston; 219. Insulated stop rod; 220. Return spring; 221. End contact spring piece; 222. Heat-inducing spring; 223. First switch terminal; 224. Second switch terminal; 225. Heat-insulating base; 226. Anti-slip pad; 227. Third alarm. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or a link; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0041] Reference Figures 1 to 11 The present invention provides a fully closed-loop control high-precision feed transmission mechanism for CNC machine tools, including a linear actuator and a servo motor 102. The linear actuator includes a slide rail structure and a ball screw pair structure. The ball screw pair structure includes a ball screw nut 107, and a damping and resistance increasing unit is provided on the side wall of the ball screw nut 107. The damping and resistance increasing unit includes a retractable linear telescopic component. The free end of the linear telescopic component is provided with several anti-slip pads 226 arranged in a stacked state. The fixed end of the linear telescopic component is provided with a first alarm 203 and a second alarm 204 respectively. The inner cavity of the linear telescopic component is provided with an elastic mechanism that can be elastically extended. The elastic mechanism includes a spring-back component and a retractable retractable component; The recessed component includes an opening and closing module disposed within its internal cavity; The opening and closing module includes a moving terminal module disposed on the free end of the retracted part and a fixed terminal module disposed on the fixed end of the retracted part, wherein the free end of the fixed terminal module abuts against the surface of the moving terminal module. The moving terminal module includes a first trigger terminal piece 214, a second trigger terminal piece 215, and a support member; During the synchronous extension and retraction of the retractor in the elastic mechanism following the linear telescopic assembly, when the fixed terminal module contacts the first trigger terminal piece 214, the second alarm 204 is triggered to open. After the spring-loaded part in the elastic mechanism returns to its initial relaxed state, the retracted part is in its initial extended state. At this time, when the moving terminal module contacts the second trigger terminal piece 215, the first alarm 203 is triggered to open.

[0042] Reference Figures 1 to 7 The present invention provides a high-precision feed transmission mechanism for CNC machine tools with full closed-loop control. The slide rail structure includes a machining stand 101, and two guide rails 103 are symmetrically connected in the inner cavity of the machining stand 101. Each guide rail 103 is slidably fitted with a movable sliding sleeve 105, and the two movable sliding sleeves 105 are connected to a feed frame 104. A milling head for milling the workpiece is installed on the feed frame 104. The ball screw pair structure also includes a screw 106 disposed in the inner cavity of the machining stand 101 and between two guide rails 103, and the two ends of the screw 106 are respectively rotatably connected to the top and bottom walls of the inner cavity of the machining stand 101. The ball screw nut 107 is threaded onto the screw 106; The servo motor 102 is connected to the top of the machining stand 101, and the output shaft of the servo motor 102 is connected to the end of the lead screw 106.

[0043] The ball screw 106 in the ball screw pair structure is driven to rotate by the servo motor 102, which in turn drives the milling head mounted on the feed frame 104 to move up and down to achieve the feed action. During this process, the friction damping that is continuously present in the ball screw nut 107 during its movement is achieved by the damping and resistance increasing unit installed on the side wall of the ball screw nut 107 and elastically abutting against the slide rail structure. This effectively suppresses the inertial kinetic energy generated by the ball screw nut 107 when the servo motor 102 stops, thus preventing large wear between the screw, nut, and balls in the ball screw nut transmission pair structure of the CNC machine tool feed transmission mechanism due to long-term use. This would prevent the feed transmission mechanism from shifting its position due to inertia when the machine stops, thus improving the positioning accuracy of the CNC machine tool feed transmission mechanism during operation.

[0044] Reference Figure 2 and Figure 3 The present invention provides a fully closed-loop control high-precision feed transmission mechanism for CNC machine tools. The linear telescopic component includes a base box 201 whose end is connected to the side wall of a ball screw nut 107. A U-shaped base 202 is slidably inserted into the opening at the end of the base box 201 away from the ball screw nut 107, and a plurality of anti-slip pads 226 in a stacked state are connected to the end of the U-shaped base 202 away from the base box 201. Both the first alarm 203 and the second alarm 204 are fixedly installed on the base box 201.

[0045] Before installing the damping and resistance-increasing unit on the side wall surface of the ball screw nut 107, first place the damping and resistance-increasing unit between the guide rail 103 and the ball screw nut 107. The retracting linear telescopic component compresses the spring piece, and when the retraction amount of the linear telescopic component reaches the preset range, the first trigger end piece 214 contacts the end contact spring piece 221 and triggers the second alarm 204 to open, alerting the operator. At this time, when the pressure of the damping and resistance-increasing unit on the surface of the guide rail 103 has reached the preset range value, the frictional damping experienced by the ball screw nut 107 during its movement is within the preset range, realizing the monitoring and sensing of the frictional damping experienced by the ball screw nut 107 during its movement. This effectively avoids the situation where the CNC machine tool feed transmission mechanism is not accurately positioned due to insufficient frictional resistance caused by inertial kinetic energy when the servo motor 102 stops.

[0046] When the damping and resistance-increasing unit is placed between the guide rail 103 and the ball screw nut 107, the second alarm 204 is not triggered. In this case, it is necessary to adjust the frictional damping of the ball screw nut 107 during its movement by increasing or decreasing the number of anti-slip pads 226 stacked at the end of the U-shaped base 202. When the damping and resistance-increasing unit is placed between the guide rail 103 and the ball screw nut 107, the second alarm 204 is activated, indicating that the pressure of the damping and resistance-increasing unit on the surface of the guide rail 103 has been adjusted to the preset range value, and the damping and resistance-increasing unit can be fixedly installed on the ball screw nut 107.

[0047] Reference Figure 8 The present invention provides a fully closed-loop control high-precision feed transmission mechanism for CNC machine tools, wherein the retractor includes a heat-conducting cylinder seat 210, which is made of a heat-conducting material; An insulating advance / retreat rod 209 is slidably inserted into one end of the heat-inducing cylinder base 210.

[0048] Reference Figure 8 and Figure 9 The present invention provides a high-precision feed transmission mechanism for CNC machine tools with full closed-loop control, wherein the fixed terminal module includes an end contact spring 221; The fixed end of the contact spring 221 is connected to the side wall of one end of the insulating advance and retreat rod 209 that extends into the inner cavity of the heat-initiating cylinder seat 210.

[0049] Reference Figure 8 and Figure 9 The present invention provides a high-precision feed transmission mechanism for CNC machine tools with full closed-loop control. The moving terminal module includes an insulating guide groove 213. A first trigger end piece 214 and a second trigger end piece 215 are respectively connected to the bottom wall of the inner cavity of the insulating guide groove 213. The insulating guide groove 213 is made of insulating and heat-conducting material. The top surfaces of the first trigger end piece 214 and the second trigger end piece 215 are flush with the bottom wall of the inner cavity of the insulating guide groove 213. The free end of the end contact spring 221 extends into the inner cavity of the insulating guide groove 213 and elastically abuts against the bottom wall of the inner cavity of the insulating guide groove 213. When the spring is in the initial relaxed state, the second trigger end piece 215 is located between the end contact spring 221 and the first trigger end piece 214.

[0050] The damping and resistance-increasing unit is removed from the ball screw nut 107 for regular maintenance. When the pressure-sensing spring 208 in the telescopic component is subjected to pressure for a long time, and its elastic force is weakened due to fatigue, the end contact spring 221 returns with a shortened stroke and contacts the second trigger end piece 215, triggering the first alarm 203 to issue a fault warning signal. This reminds the staff to replace or repair the pressure-sensing spring 208 in the damping and resistance-increasing unit in a timely manner, preventing the friction damping of the ball screw nut 107 from decreasing due to the weakening elastic force of the pressure-sensing spring 208. This helps to further improve the positioning accuracy of the CNC machine tool feed transmission mechanism.

[0051] Reference Figures 8 to 11 The present invention provides a fully closed-loop control high-precision feed transmission mechanism for CNC machine tools. The supporting component includes a forced piston 218, and a plurality of insulating driven cylinders 217 are inserted and fixed on the forced piston 218. The insulating driven cylinders 217 are made of insulating and heat-conducting material. One end of the insulating driven cylinder 217 passes through the forced piston 218 and is slidably inserted with an insulating push rod 219. A return spring 220 is sleeved on the insulating push rod 219. Each of the several insulating driven cylinders 217 has a first switch terminal 223 and a second switch terminal 224 arranged opposite to each other in its inner cavity, and one end of the insulating rod 219 corresponding to the insulating driven cylinder 217 extends into the inner cavity of the insulating driven cylinder 217 and is connected to the second switch terminal 224. One end of the first switch terminal 223 is connected to a heat-drawing spring 222, and the end of the heat-drawing spring 222 away from the first switch terminal 223 is connected to the end of the inner cavity of the insulating driven cylinder 217. The support structure also includes a liquid phase limiting layer 216; An inner cavity is provided inside the wall of the heat-generating cylinder seat 210 at a position corresponding to the position of the insulating guide groove 213; The forced piston 218 slides within the sealed inner cavity; A liquid phase limiting layer 216 is filled into the inner cavity; The end of the insulating driven cylinder 217 away from the insulating push rod 219 is sealed and passes through the end of the inner cavity and extends into the inner cavity of the heat-conducting cylinder seat 210 to connect with the insulating guide groove 213. The end of the insulating rod 219 away from the insulating driven cylinder 217 is connected to the end of the inner cavity; One end of the return spring 220 is connected to the end of the insulated driven cylinder 217, and the other end is connected to the end of the inner cavity. The liquid phase limiting layer 216 is located on the side of the forced piston 218 near the insulating guide groove 213; A vent is also provided on the side wall of the heat-conducting cylinder seat 210 at a position corresponding to the inner cavity, which is connected to the end of the inner cavity away from the insulating guide groove 213.

[0052] When the contact spring 221 in the moving terminal module comes into contact with the first trigger terminal 214 or the second trigger terminal 215 in the fixed terminal module, the heat generated is continuously conducted through the insulating driven cylinder 217 to the liquid phase limiting layer 216, and then the liquid phase limiting layer 216 dissipates heat and cools it, so that the above-mentioned "terminal" can be maintained within a suitable temperature range, improving the reliability and stability of the operation of the damping and resistance increasing unit.

[0053] Reference Figures 8 to 11 The present invention provides a high-precision feed transmission mechanism for CNC machine tools with full closed-loop control. The spring includes a pressure-sensitive spring 208 sleeved on the outer periphery of the retractor. Both ends of the pressure-sensitive spring 208 are connected to heat-conducting seats 205. The opposite ends of the two heat-conducting seats 205 are connected to heat-insulating bases 225. The heat-conducting seats 205 are made of insulating and heat-conducting material, and the heat-insulating bases 225 are made of heat-insulating material. One of the heat-insulating bases 225 is connected to the end of the inner cavity of the U-shaped base 202, and the other heat-insulating base 225 is connected to the end of the inner cavity of the base box 201. One of the heat-conducting seats 205 is connected to the end of the heat-initiating cylinder seat 210, and the other heat-conducting seat 205 is connected to the end of the insulating advance and retreat rod 209. The heat-conducting seat 205 connected to the end of the heat-initiating cylinder seat 210 is provided with an electric heating element 207 inside its wall. When the return element is in the initial relaxed state, the pressure-sensing spring 208 is in the initial relaxed state, and at this time, the end contact spring 221 is not in contact with the second trigger end piece 215 and the first trigger end piece 214. When the first switch terminal 223 contacts the second switch terminal 224, the series circuit consisting of the first switch terminal 223, the second switch terminal 224, the electric heating element 207, and the third alarm 227 is turned on.

[0054] During the cold season, when the liquid phase limiting layer 216 in the damping and resistance increasing unit, which was originally liquid, freezes into ice due to the low temperature, its volume increases and drives the first switch terminal 223 to contact the second switch terminal 224 through the forced piston. At the same time, the third alarm 227 and the electric heating element 207 are triggered. The activated third alarm 227 reminds the operator that the liquid phase limiting layer 216 has turned into a frozen state and the operation of the feed transmission mechanism needs to be stopped.

[0055] The heat generated by the electric heating element 207 is transferred to the heat-conducting base 205 to the heat-initiating cylinder base 210. After the solidified liquid phase limiting layer 216 melts into a liquid state, the first switch terminal 223 and the second switch terminal 224 lose contact. During the melting process of the liquid phase limiting layer 216, under the elastic force of the return spring 220, the driven piston 218 drives the insulating guide groove 213 to move through the insulating driven cylinder 217, so that the end contact spring 221 is pressed tightly against the bottom wall surface of the inner cavity of the insulating guide groove 213 again, preventing the liquid phase limiting layer 216 from cooling due to the low ambient temperature. While the solidification drives the piston 218 to move, the insulating driven cylinder 217 drives the insulating guide groove 213 to move away from the end contact spring 221. This causes the end contact spring 221 to subsequently make poor contact with the first trigger end piece 214 or the second trigger end piece 215, or even to detach. This seriously affects the accuracy and reliability of monitoring and sensing the frictional damping experienced by the ball screw nut 107 during its movement. This enables the fault self-correction, allowing the feed transmission mechanism to quickly return to normal operation, while also helping to ensure the positioning accuracy of the CNC machine tool feed transmission mechanism.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision feed transmission mechanism with fully closed-loop control for CNC machine tools, characterized in that: It includes a linear actuator and a servo motor (102), wherein the linear actuator includes a slide rail structure and a ball screw pair structure; The ball screw pair structure includes a ball screw nut (107), and a damping and resistance increasing unit is provided on the side wall of the ball screw nut (107). The damping and resistance increasing unit includes a retractable linear telescopic component. The free end of the linear telescopic component is provided with a number of anti-slip pads (226) arranged in a stacked state. The fixed end of the linear telescopic component is provided with a first alarm (203) and a second alarm (204). The inner cavity of the linear telescopic component is provided with an elastic mechanism that can be elastically extended. The elastic mechanism includes a spring-back component and a retractable retractable component; The retractable component includes an opening and closing module disposed within its inner cavity; The opening and closing module includes a moving terminal module disposed on the free end of the retracted member and a fixed terminal module disposed on the fixed end of the retracted member, wherein the free end of the fixed terminal module abuts against the surface of the moving terminal module. The moving terminal module includes a first trigger terminal piece (214), a second trigger terminal piece (215), and a support member; During the synchronous extension and retraction of the retractor in the elastic mechanism following the linear telescopic assembly, when the fixed terminal module contacts the first trigger terminal piece (214), the second alarm (204) is triggered to open; After the spring-loaded part in the elastic mechanism returns to the initial relaxed state, the retracted part is in the initial extended state. At this time, when the moving terminal module contacts the second trigger end piece (215), the first alarm (203) is triggered to open.

2. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 1, characterized in that: The slide rail structure includes a processing stand (101), and two guide rails (103) are symmetrically connected in the inner cavity of the processing stand (101). Each guide rail (103) is slidably fitted with a movable sleeve (105), and the two movable sleeves (105) are connected to a common feed frame (104), on which a milling head for milling the workpiece is installed; The ball screw pair structure also includes a screw (106) disposed in the inner cavity of the processing stand (101) and between two guide rails (103), and the two ends of the screw (106) are respectively rotatably connected to the top and bottom walls of the inner cavity of the processing stand (101); The ball screw nut (107) is threaded onto the screw (106); The servo motor (102) is connected to the top of the machining stand (101), and the output shaft of the servo motor (102) is connected to the end of the lead screw (106).

3. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 1, characterized in that: The linear telescopic assembly includes a base cylinder (201) whose end is connected to the side wall of the ball screw nut (107). A U-shaped base (202) is slidably inserted into the opening at the end of the base cylinder (201) away from the ball screw nut (107), and several anti-slip pads (226) in a stacked state are connected to the end of the U-shaped base (202) away from the base cylinder (201). The first alarm (203) and the second alarm (204) are both fixedly installed on the base box (201).

4. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 1, characterized in that: The recessed component includes a heat extraction cylinder seat (210); An insulating advance / retreat rod (209) is slidably inserted into one end of the heat-generating cylinder base (210).

5. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 4, characterized in that: The fixed terminal module includes an end contact spring (221). The fixed end of the end contact spring (221) is connected to the side wall of one end of the insulating advance and retreat rod (209) that extends into the inner cavity of the heat-conducting cylinder seat (210).

6. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 5, characterized in that: The moving terminal module includes an insulating guide groove (213), and a first trigger end piece (214) and a second trigger end piece (215) are respectively connected to the bottom wall of the inner cavity of the insulating guide groove (213). The top surfaces of the first trigger end piece (214) and the second trigger end piece (215) are flush with the bottom wall of the inner cavity of the insulating guide groove (213); The free end of the end contact spring (221) extends into the inner cavity of the insulating guide groove (213) and elastically abuts against the bottom wall of the inner cavity of the insulating guide groove (213). When the spring is in the initial relaxed state, the second trigger end piece (215) is between the end contact spring (221) and the first trigger end piece (214).

7. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 6, characterized in that: The support member includes a forced piston (218), and a plurality of insulated driven cylinders (217) are inserted and fixed on the forced piston (218). One end of the insulating driven cylinder (217) passes through the forced piston (218) and is slidably inserted with an insulating push rod (219), and a return spring (220) is sleeved on the insulating push rod (219). Each of the insulating driven cylinders (217) has a first switch terminal (223) and a second switch terminal (224) arranged opposite to each other in its inner cavity, and one end of an insulating rod (219) corresponding to the insulating driven cylinder (217) extends into the inner cavity of the insulating driven cylinder (217) and is connected to the second switch terminal (224); One end of the first switch terminal (223) is connected to a heat-drawing spring (222), and the end of the heat-drawing spring (222) away from the first switch terminal (223) is connected to the end of the inner cavity of the insulating driven cylinder (217); The support component also includes a liquid phase limiting layer (216).

8. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 7, characterized in that: The heat-generating cylinder seat (210) has an inner cavity at the position corresponding to the insulating guide groove (213) inside its wall thickness; The forced piston (218) slides in a sealed manner within the inner cavity; The liquid phase limiting layer (216) is filled in the inner cavity; The end of the insulating driven cylinder (217) away from the insulating abutment (219) is sealed through the end of the inner cavity and extends into the inner cavity of the heat-conducting cylinder seat (210) and is connected to the insulating guide groove (213); The end of the insulating rod (219) away from the insulating driven cylinder (217) is connected to the end of the inner cavity; One end of the return spring (220) is connected to the end of the insulating driven cylinder (217), and the other end is connected to the end of the inner cavity; The liquid phase limiting layer (216) is located on the side of the forced piston (218) near the insulating guide groove (213); A vent is also provided on the side wall of the heat-generating cylinder seat (210) at a position corresponding to the inner cavity, which is connected to the end of the inner cavity away from the insulating guide groove (213).

9. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 7, characterized in that: The rebound component includes a pressure-sensing spring (208) sleeved on the outer periphery of the retracted component. Both ends of the pressure-sensing spring (208) are connected to heat-conducting seats (205), and the opposite ends of the two heat-conducting seats (205) are connected to heat-insulating bases (225). One of the heat-insulating bases (225) is connected to the end of the inner cavity of the U-shaped base (202), and the other heat-insulating base (225) is connected to the end of the inner cavity of the base box (201); One of the heat-conducting seats (205) is connected to the end of the heat-inducing cylinder seat (210), and the other heat-conducting seat (205) is connected to the end of the insulating advance and retreat bar (209). The heat-conducting seat (205) connected to the end of the heat-inducing cylinder seat (210) has an electric heating element (207) inside its wall.

10. The high-precision feed transmission mechanism for CNC machine tools with fully closed-loop control according to claim 9, characterized in that: When the spring is in the initial relaxed state, the pressure-sensing spring (208) is in the initial relaxed state, and at this time, the end contact spring (221) does not contact the second trigger end piece (215) and the first trigger end piece (214); When the first switch terminal (223) contacts the second switch terminal (224), the series circuit consisting of the first switch terminal (223), the second switch terminal (224), the electric heating element (207) and the third alarm (227) is turned on.

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