An automatic protection system for a numerically controlled machine tool

Abstract

The application discloses an automatic protection system of a numerical control machine tool and relates to the technical field of numerical control machine tools.The automatic protection system comprises a base, a lifting assembly and a first translation assembly, the lifting assembly and the first translation assembly are arranged on the top of the base, a second translation assembly is movably connected to the top of the first translation assembly, a fixed clamp is arranged on the second translation assembly, a main shaft motor is arranged on the top of the second end of the lifting assembly, the end of the rotating shaft of the main shaft motor penetrates through the second end of the lifting assembly and is arranged above the fixed clamp and is connected with a tool bit, a control module, a sensor and a main shaft driving circuit, the control module is connected with the sensor and the main shaft driving circuit, the main shaft driving circuit is connected with the control module, when the main shaft motor is in a working state and the sensor detects that a human body is close, the control module controls the main shaft motor to stop working through the main shaft driving circuit.The application can not only prevent iron scraps from being ejected to hurt people, but also can efficiently and safely take out and place parts.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of numerical control machine tools, in particular to an automatic protection system of a numerical control machine tool. BACKGROUND

[0002] A numerical control machine tool is a kind of automatic machine tool equipped with a program control system. The control system can logically process programs with control codes or other symbolic instructions, and translate them into coded numbers, which are input into the numerical control device through information carriers. After operation and processing, the numerical control device sends various control signals to control the machine tool, and automatically processes parts according to the required shape and size on the drawing.

[0003] The numerical control machine tool solves the problem of processing complex, precise, small batch and multi-variety parts, and is a flexible and high-efficiency automatic machine tool, representing the development direction of modern machine tool control technology, and is a typical mechatronics product.

[0004] Some numerical control machine tools are equipped with a protective cover with a working opening to prevent iron filings from being ejected during processing and injuring people. The working opening of the protective cover is provided with side sliding doors that slide to both sides. A glass window for observing the inside of the machine tool is provided on the side sliding door. However, after long-term use of the numerical control machine tool or during work, impurities such as cooling liquid may accumulate on the glass window, which makes it difficult to observe the internal working condition of the numerical control machine tool during work. If you want to observe the internal working condition, you must remove the side sliding door, which may cause safety hazards when the numerical control machine tool is in a working state.

[0005] Moreover, after the part is processed, the workpiece on the workbench needs to be taken out manually, and the new part to be processed needs to be placed on the workbench. If the operator forgets to turn off the spindle motor or takes out and places the workpiece without turning off the spindle motor in order to improve efficiency, there is a risk of bumping into the spindle. SUMMARY

[0006] The present application aims to provide an automatic protection system of a numerical control machine tool, which is provided with a sensor. When the spindle motor is in a working state and the sensor detects a human body, the control module controls the spindle motor to stop working through the spindle driving circuit. After the human body moves away, the spindle motor resumes working. This not only prevents iron filings from being ejected and injuring people, but also efficiently and safely takes out and places the workpiece.

[0007] To solve the above technical problems, the present application adopts the following technical scheme:

[0008] In one aspect of the present application, an automatic protection system for a numerical control machine tool is provided. The numerical control machine tool comprises a base, a lifting assembly, and a first translation assembly. The first translation assembly is arranged on the top of the base, and the first end of the lifting assembly is arranged on the top of the first end of the base. The automatic protection system comprises a control module, a sensor, and a spindle drive circuit. The control module is connected to the sensor and the spindle drive circuit, and the spindle drive circuit is connected to control the spindle motor. When the spindle motor is in a working state and the sensor detects a human body close to the numerical control machine tool, the control module controls the spindle motor to stop working through the spindle drive circuit.

[0009] In some embodiments, the lifting assembly comprises a fixed support, a lifting slide rail, a slidable support, and a lifting control motor. The bottom of the fixed support is connected to the top of the first end of the base. The lifting slide rail is arranged vertically on the fixed support. The spindle motor is arranged on the top of the slidable support. The spindle motor shaft penetrates the slidable support and is arranged above the fixed clamp. The slidable support is movably connected to the lifting slide rail. The lifting control motor is arranged on the top of the fixed support. The spindle motor shaft is connected to control the slidable support to move. The first translation assembly comprises a first translation slide rail, a support table, and a first translation control motor. The first translation slide rail is arranged on the top of the base. The bottom of the support table is movably connected to the first translation slide rail. The first translation control motor is arranged on one end of the first translation slide rail. The spindle motor shaft is connected to control the support table to move. The second translation assembly comprises a second translation slide rail and a second translation control motor. The second translation slide rail is arranged on the top of the support table. The bottom of the fixed clamp is movably connected to the second translation slide rail. The second translation control motor is arranged on one end of the second translation slide rail. The spindle motor shaft is connected to control the fixed clamp to move.

[0010] In some embodiments, the sensor includes a first ultrasonic sensor, a second ultrasonic sensor and a third ultrasonic sensor which are structurally identical, the first ultrasonic sensor is arranged on the slidable bracket for detecting the front side of the base opposite to the first end of the base, the second ultrasonic sensor and the third ultrasonic sensor are arranged on the outer side wall of the base, and the second ultrasonic sensor and the third ultrasonic sensor are respectively used for detecting the left and right sides of the base; the first ultrasonic sensor includes an ultrasonic wave transmitting circuit and an ultrasonic wave receiving circuit, the ultrasonic wave transmitting circuit includes an ultrasonic wave transmitter, a first NPN triode, a first PNP triode, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor, the collector of the first NPN triode is connected to a direct current power source through the first resistor, the emitter of the first NPN triode is connected to the emitter of the first PNP triode and the first electrode of the ultrasonic wave transmitter, the collector of the first PNP triode is grounded through the third resistor, the base of the first NPN triode and the base of the first PNP triode are connected to the control module through the second resistor, the second electrode of the ultrasonic wave transmitter is connected to one end of the fourth resistor and one end of the fifth resistor, the other end of the fourth resistor is connected to a direct current power source, and the other end of the fifth resistor is grounded.

[0011] In some embodiments, the ultrasonic wave receiving circuit includes an ultrasonic wave receiver, a second NPN triode, a third NPN triode, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor, the first electrode of the ultrasonic wave receiver is connected to the base of the second NPN triode and one end of the sixth resistor, the second electrode of the ultrasonic wave receiver is grounded, the collector of the second NPN triode is connected to the other end of the sixth resistor, one end of the first capacitor and one end of the seventh resistor, the other end of the seventh resistor is connected to a direct current power source, the emitter of the second NPN triode is grounded, the other end of the first capacitor is connected to one end of the eighth resistor, one end of the ninth resistor and the base of the third NPN triode, the collector of the third NPN triode is connected to the other end of the eighth resistor, one end of the tenth resistor and the control module, the other end of the ninth resistor and the emitter of the third NPN triode are grounded, and the other end of the tenth resistor is connected to a direct current power source.

[0012] In some embodiments, the ultrasonic receiving circuit further comprises an operational amplifier, an eleventh resistor, a twelfth resistor, a thirteenth resistor and a fourteenth resistor, an in-phase input end of the operational amplifier is connected to one end of the eleventh resistor and one end of the twelfth resistor, the other end of the eleventh resistor is connected to a collector of the third NPN transistor, the other end of the twelfth resistor is connected to an output end of the operational amplifier and one end of the thirteenth resistor, an inverse-phase input end of the operational amplifier is grounded through the fourteenth resistor, the other end of the thirteenth resistor is connected to the control module.

[0013] In some embodiments, the ultrasonic receiving circuit further comprises a first diode and a fifteenth resistor, a positive electrode of the first diode is connected to the other end of the thirteenth resistor, a negative electrode of the first diode is connected to one end of the fifteenth resistor, the second ultrasonic sensor, the third ultrasonic sensor and the control module, the other end of the fifteenth resistor is grounded.

[0014] In some embodiments, the automatic protection system further comprises a detection switch circuit, the detection switch circuit comprises a fourth NPN transistor, a first relay, a second diode, a sixteenth resistor, a seventeenth resistor and an eighteenth resistor, a collector of the fourth NPN transistor is connected to one end of a coil end of the first relay and a positive electrode of the second diode, a negative electrode of the second diode is connected to the other end of the coil end of the first relay and one end of the eighteenth resistor, the other end of the eighteenth resistor is connected to a direct current power supply, one end of a contactor of the first relay is connected to the negative electrode of the first diode, the second ultrasonic sensor and the third ultrasonic sensor, the other end of the contactor of the first relay is connected to the control module, a base of the fourth NPN transistor is connected to one end of the seventeenth resistor and the control module through the sixteenth resistor, an emitter of the fourth NPN transistor and the other end of the seventeenth resistor are grounded.

[0015] In some embodiments, the detection switch circuit further comprises a second PNP transistor and a nineteenth resistor, an emitter of the second PNP transistor is connected to the direct current power supply through the nineteenth resistor, a base of the second PNP transistor is connected to the collector of the fourth NPN transistor, the base of the fourth NPN transistor is connected to a collector of the second PNP transistor through the sixteenth resistor.

[0016] In some embodiments, the automatic protection system further comprises a lifting motor drive circuit, a first translation motor drive circuit and a second translation motor drive circuit which are identical in circuit structure, the lifting motor drive circuit is connected to control the lifting control motor, the first translation motor drive circuit is connected to control the first translation control motor, and the second translation motor drive circuit is connected to control the second translation control motor; the lifting motor drive circuit comprises a fifth NPN transistor, a sixth NPN transistor, a second relay, a third relay, a third diode, a fourth diode, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor and a twenty-fifth resistor, the collector of the fifth NPN transistor is connected to one end of the coil of the second relay and the anode of the third diode, the cathode of the third diode is connected to the other end of the coil of the second relay and one end of the twenty-second resistor, the other end of the twenty-second resistor is connected to a direct current power supply, the base of the fifth NPN transistor is connected to one end of the twenty-first resistor and the control module through the twentieth resistor, the emitter of the fifth NPN transistor and the other end of the twenty-first resistor are grounded, the collector of the sixth NPN transistor is connected to one end of the coil of the third relay and the anode of the fourth diode, the cathode of the fourth diode is connected to the other end of the coil of the third relay and one end of the twenty-fifth resistor, the other end of the twenty-fifth resistor is connected to a direct current power supply, the base of the sixth NPN transistor is connected to one end of the twenty-fourth resistor and the control module through the twenty-third resistor, and the emitter of the sixth NPN transistor and the other end of the twenty-fourth resistor are grounded; one end of the first contactor of the second relay is connected to a live wire, one end of the first contactor of the third relay is connected to a zero wire, the other end of the first contactor of the second relay and the other end of the first contactor of the third relay are connected to the first electrode of the lifting control motor, one end of the second contactor of the second relay is connected to a zero wire, one end of the second contactor of the third relay is connected to a live wire, the other end of the second contactor of the second relay and the other end of the second contactor of the third relay are connected to the second electrode of the lifting control motor.

[0017] In some embodiments, the main shaft driving circuit comprises a seventh NPN triode, a fourth relay, a fifth diode, a twenty-sixth resistor, a twenty-seventh resistor and a twenty-eighth resistor, a base of the seventh NPN triode is connected to one end of the twenty-seventh resistor and the control module through the twenty-sixth resistor, a collector of the seventh NPN triode is connected to one end of a coil end of the fourth relay and a positive pole of the fifth diode, a negative pole of the fifth diode is connected to the other end of the coil end of the fourth relay and one end of the twenty-eighth resistor, the other end of the twenty-eighth resistor is connected to a direct current power supply, an emitter of the seventh NPN triode and the other end of the twenty-seventh resistor are grounded, one end of a first contactor of the fourth relay is connected to a live wire, one end of a second contactor of the fourth relay is connected to a zero wire, the other end of the first contactor and the other end of the second contactor of the fourth relay are respectively connected to two poles of the main shaft motor.

[0018] According to the automatic protection system of the numerical control machine tool, at least the following beneficial effects are achieved: when the main shaft motor is in a working state and the sensor detects that a human body is close, the control module controls the main shaft motor to stop working through the main shaft driving circuit; when the human body is far away, the control module controls the main shaft motor to resume working through the main shaft driving circuit, thereby saving the step of turning on and off the main shaft motor. The application can not only prevent iron scraps from being ejected to hurt people, but also efficiently and safely take out and place parts. The first diode and the fifteenth resistor are added behind each ultrasonic sensor to prevent mutual interference of the three ultrasonic sensors. When one of the sensors detects that a human body is close, the control module controls the main shaft motor to stop working through the main shaft driving circuit, thereby improving the detection accuracy. The application is also provided with a detection switch circuit, which can turn on and off the sensor at any time, thereby improving the flexibility of use.

[0019] It should be understood that the above general description and the following detailed description are only exemplary and cannot limit the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creating any creative labor.

[0021] Figure 1 It is a structural schematic diagram of the numerical control machine tool according to the embodiment;

[0022] Figure 2 It is an exploded structural schematic diagram of the base and the fixed support according to the embodiment;

[0023] Figure 3 A schematic diagram of an automatic protection system according to an embodiment;

[0024] Figure 4 A schematic diagram of an ultrasonic wave transmitting circuit according to an embodiment;

[0025] Figure 5 A schematic diagram of an ultrasonic wave receiving circuit according to an embodiment;

[0026] Figure 6 A schematic diagram of a detection switch circuit according to an embodiment;

[0027] Figure 7 A schematic diagram of a lifting motor driving circuit according to an embodiment;

[0028] Figure 8 A schematic diagram of a main shaft driving circuit according to an embodiment.

[0029] The reference signs are explained as follows: 1, base; 2, lifting assembly; 201, fixed support; 202, lifting slide rail; 203, slidable support; 204, lifting control motor; 3, first translation assembly; 301, first translation slide rail; 302, support table; 303, first translation control motor; 4, second translation assembly; 401, second translation slide rail; 402, second translation control motor; 5, fixed clamp; 6, main shaft motor; 7, tool bit; 8, first ultrasonic sensor; 9, second ultrasonic sensor; 10, third ultrasonic sensor. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0031] In the description of the present application, it should be understood that the terms “middle”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only intended to facilitate the description of the present application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0032] The terms "first", "second", "third", are used only for descriptive purposes and should not be construed as implying or suggesting relative importance or an indicated number of the technical features indicated. Thus, the features defined with "first", "second", "third" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified and limited.

[0033] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "communication", "installation", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0034] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the examples set forth herein; rather, these example implementations are provided so that this disclosure will be thorough and complete, and will fully convey the inventive concept of the example implementations to those skilled in the art. The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings are not necessarily to scale, the same reference numerals in the drawings refer to the same or similar portions, and thus repeated description thereof will be omitted.

[0035] The technical solutions of the embodiments of the present application will be briefly described below:

[0036] According to some embodiments, as shown in Figure 1 , Figure 3 The present application provides an automatic protection system for a numerical control machine tool, as shown in Figure 1 The numerical control machine tool comprises:

[0037] A base 1, a lifting assembly 2, and a first translation assembly 3, the first translation assembly 3 is arranged on the top of the base 1, and the first end of the lifting assembly 2 is arranged on the top of the first end of the base 1;

[0038] A second translation assembly 4, the bottom of the second translation assembly 4 is movably connected with the top of the first translation assembly 3, and the upper end of the second translation assembly 4 is provided with a fixed clamp 5, and the second end of the lifting assembly 2 is arranged above the fixed clamp 5;

[0039] A spindle motor 6, the spindle motor 6 is arranged on the top of the second end of the lifting assembly 2, the shaft end of the spindle motor 6 penetrates through the second end of the lifting assembly 2 and is arranged above the fixed clamp 5, and the shaft end of the spindle motor 6 is connected with a tool head 7.

[0040] Wherein, the lifting assembly 2 is used for controlling the spindle motor 6 to move in the Z-axis direction, the first translation assembly 3 is used for controlling the fixed clamp 5 to move in the Y-axis direction, and the second translation assembly 4 is used for controlling the fixed clamp 5 to move in the X-axis direction, so as to facilitate the part machining.

[0041] The automatic protection system comprises:

[0042] The control module, the sensor and the spindle driving circuit, the control module is connected with the sensor and the spindle driving circuit respectively, and the spindle driving circuit is connected with the spindle motor 6.

[0043] The working principle of the above embodiment is that when the spindle motor 6 is in a working state and the sensor detects that the human body is close, the control module controls the spindle motor 6 to stop working through the spindle driving circuit; when the human body is far away, the control module controls the spindle motor 6 to resume working through the spindle driving circuit, thereby saving the step of turning on and off the spindle motor 6. The application can not only prevent iron scraps from being ejected to hurt people, but also efficiently and safely take out and place parts.

[0044] The above and other embodiments of the present application will be more apparent from the following description of the specification taken in conjunction with the accompanying drawings. Figures 1 to 6 The preferred embodiments of the present disclosure are further elaborated.

[0045] According to some embodiments, as shown in Figures 1 to 2 The lifting assembly 2 comprises a fixed support 201, a lifting slide rail 202, a slidable support 203 and a lifting control motor 204, and the specific connection modes are as follows,

[0046] The bottom of the fixed support 201 is connected with the top of the first end of the base 1, the lifting slide rail 202 is vertically arranged on the fixed support 201, the spindle motor 6 is arranged on the top of the slidable support 203, the shaft end of the spindle motor 6 penetrates through the slidable support 203 and is arranged above the fixed clamp 5, the slidable support 203 is movably connected with the lifting slide rail 202, the lifting control motor 204 is arranged on the top of the fixed support 201, and the shaft of the lifting control motor 204 is connected to control the slidable support 203 to move;

[0047] As shown in Figures 1 to 2 The first translation assembly 3 comprises a first translation slide rail 301, a support table 302 and a first translation control motor 303, and the specific connection modes are as follows,

[0048] The first translation slide rail 301 is arranged on the top of the base 1, the bottom of the support table 302 is movably connected with the first translation slide rail 301, the first translation control motor 303 is arranged on one end of the first translation slide rail 301, and the shaft of the first translation control motor 303 is connected to control the support table 302 to move;

[0049] As shown in Figures 1 to 2As shown, the second translation assembly 4 includes a second translation sliding rail 401 and a second translation control motor 402, and the specific connection mode is as follows,

[0050] The second translation sliding rail 401 is arranged on the top of the support table 302, the bottom of the fixed clamp 5 is movably connected with the second translation sliding rail 401, the second translation control motor 402 is arranged on one end of the second translation sliding rail 401, and the rotating shaft of the second translation control motor 402 is connected with the control fixed clamp 5 to move.

[0051] According to some embodiments, as Figure 1 As shown, the sensor includes first, second and third ultrasonic sensors 8, 9 and 10 which have the same structure, the first ultrasonic sensor 8 is arranged on the slidable support 203 and is used to detect the front side of the base 1 opposite to the first end of the base 1, the second and third ultrasonic sensors 9 and 10 are arranged on the outer side wall of the base 1 and are respectively used to detect the left and right sides of the base 1.

[0052] Specifically, as Figure 1 As shown, the fixed support 201 is arranged at the rear end of the base 1, the first ultrasonic sensor 8 detects whether a human body approaches from the front side, and the second and third ultrasonic sensors 9 and 10 detect whether a human body approaches from the left and right sides.

[0053] Further, the first ultrasonic sensor 8 includes an ultrasonic wave transmitting circuit and an ultrasonic wave receiving circuit, as Figure 4 As shown, the ultrasonic wave transmitting circuit includes an ultrasonic wave transmitter LS1, a first NPN triode QN1, a first PNP triode QP1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5, and the specific connection mode is as follows,

[0054] The collector of the first NPN triode QN1 is connected with a direct current power supply through the first resistor R1, the emitter of the first NPN triode QN1 is connected with the emitter of the first PNP triode QP1 and the first electrode of the ultrasonic wave transmitter LS1, the collector of the first PNP triode QP1 is grounded through the third resistor R3, the base of the first NPN triode QN1 and the base of the first PNP triode QP1 are connected with a control module through the second resistor R2, the second electrode of the ultrasonic wave transmitter LS1 is connected with one end of the fourth resistor R4 and one end of the fifth resistor R5, the other end of the fourth resistor R4 is connected with the direct current power supply, and the other end of the fifth resistor R5 is grounded.

[0055] Further, as Figure 5As shown, the ultrasonic receiving circuit includes an ultrasonic receiver LS2, a second NPN transistor QN2, a third NPN transistor QN3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10, which are connected as follows,

[0056] The first electrode of the ultrasonic receiver LS2 is connected to the base of the second NPN transistor QN2 and one end of the sixth resistor R6, the second electrode of the ultrasonic receiver LS2 is grounded, the collector of the second NPN transistor QN2 is connected to the other end of the sixth resistor R6, one end of a first capacitor, and one end of the seventh resistor R7, the other end of the seventh resistor R7 is connected to a direct current power supply, the emitter of the second NPN transistor QN2 is grounded, the other end of the first capacitor is connected to one end of the eighth resistor R8, one end of the ninth resistor R9, and the base of the third NPN transistor QN3, the collector of the third NPN transistor QN3 is connected to the other end of the eighth resistor R8, one end of the tenth resistor R10, and a control module, the other end of the ninth resistor R9 and the emitter of the third NPN transistor QN3 are grounded, and the other end of the tenth resistor R10 is connected to the direct current power supply.

[0057] The working principle of the above embodiment is that the control module outputs a square wave signal to the base of the first NPN transistor QN1 and the base of the first PNP transistor QP1, and the first NPN transistor QN1 and the first PNP transistor QP1 are continuously switched on, so that the ultrasonic transmitter LS1 emits an ultrasonic signal. When the human body is close, the ultrasonic signal of the ultrasonic transmitter LS1 is reflected by the human body and received by the ultrasonic receiver LS2, the ultrasonic receiver LS2 converts the ultrasonic signal into an electric signal and outputs it, and then the second NPN transistor QN2 and the third NPN transistor QN3 amplify the electric signal and output it to the control module. After the control module detects the electric signal converted by the ultrasonic receiver LS2, it is determined that a person is close, and the main shaft driving circuit is controlled to stop the main shaft motor 6 from working.

[0058] When the human body is far away, the ultrasonic receiver LS2 cannot receive the reflected ultrasonic signal, and there is no electric signal output. The control module does not detect the electric signal converted by the ultrasonic receiver LS2, and determines that no one is close, and the main shaft driving circuit is controlled to restore the main shaft motor 6 to work.

[0059] According to some embodiments, as shown in FIG. 2, Figure 5 As shown, the ultrasonic receiving circuit further includes an operational amplifier U, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, and a fourteenth resistor R14, which play a role in further signal amplification, and are connected as follows,

[0060] The non-inverting input of the operational amplifier U is connected to one end of the eleventh resistor R11 and one end of the twelfth resistor R12, the other end of the eleventh resistor R11 is connected to the collector of the third NPN transistor QN3, the other end of the twelfth resistor R12 is connected to the output of the operational amplifier U and one end of the thirteenth resistor R13, the inverting input of the operational amplifier U is grounded through the fourteenth resistor R14, and the other end of the thirteenth resistor R13 is connected to the control module.

[0061] According to some embodiments, as shown in Figure 5 The ultrasonic receiving circuit further includes a first diode D1 and a fifteenth resistor R15, which are connected as follows,

[0062] The positive electrode of the first diode D1 is connected to the other end of the thirteenth resistor R13, the negative electrode of the first diode D1 is connected to one end of the fifteenth resistor R15, the second ultrasonic sensor 9, the third ultrasonic sensor 10 and the control module, and the other end of the fifteenth resistor R15 is grounded.

[0063] The working principle of the above embodiment is that when one of the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 detects that a human body is close, the control module controls the main shaft motor 6 to stop working, so the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are connected in parallel to the detection end of the control module. However, the electrical signals output by the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 may affect each other. In order to prevent the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 from affecting each other, diodes are added in the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10. The first diode D1 of the first ultrasonic sensor 8 is used to prevent the electrical signals output by the second ultrasonic sensor 9 and the third ultrasonic sensor 10 from flowing into the first ultrasonic sensor 8. The structures of the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are the same as that of the first ultrasonic sensor 8, so the diodes arranged in the second ultrasonic sensor 9 and the third ultrasonic sensor 10 also have the same effect.

[0064] According to some embodiments, as shown in Figure 6 The automatic protection system further includes a detection switch circuit, which includes a fourth NPN transistor QN4, a first relay K1, a second diode D2, a sixteenth resistor R16, a seventeenth resistor R17 and an eighteenth resistor R18, which are connected as follows,

[0065] The collector of the fourth NPN transistor QN4 is connected to one end of the coil end of the first relay K1 and the anode of the second diode D2, the cathode of the second diode D2 is connected to the other end of the coil end of the first relay K1 and one end of the eighteenth resistor R18, the other end of the eighteenth resistor R18 is connected to the direct current power supply, one end of the contactor K11 of the first relay K1 is connected to the cathode of the first diode D1, the second ultrasonic sensor 9 and the third ultrasonic sensor 10, the other end of the contactor K11 of the first relay K1 is connected to the control module, the base of the fourth NPN transistor QN4 is connected to one end of the seventeenth resistor R17 and the control module through the sixteenth resistor R16, the emitter of the fourth NPN transistor QN4 and the other end of the seventeenth resistor R17 are grounded.

[0066] The working principle of the above embodiment is that when the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are required to detect whether a human body is close, the control module outputs a high-level signal to the base of the fourth NPN transistor QN4, the fourth NPN transistor QN4 is turned on, the contactor K11 of the first relay K1 is attracted, and the control module can receive the electrical signal converted by the ultrasonic receiver LS2 in the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10.

[0067] When the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are not required to detect whether a human body is close, the control module outputs a low-level signal to the base of the fourth NPN transistor QN4, the fourth NPN transistor QN4 is cut off, the contactor K11 of the first relay K1 is disconnected, and the control module cannot receive the electrical signal converted by the ultrasonic receiver LS2 in the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10.

[0068] Further, as shown in Figure 6 , the detection switch circuit further comprises a second PNP transistor QP2 and a nineteenth resistor R19, and the specific connection mode is as follows,

[0069] The emitter of the second PNP transistor QP2 is connected to the direct current power supply through the nineteenth resistor R19, the base of the second PNP transistor QP2 is connected to the collector of the fourth NPN transistor QN4, and the base of the fourth NPN transistor QN4 is connected to the collector of the second PNP transistor QP2 through the sixteenth resistor R16.

[0070] The second PNP transistor QP2 and the fourth NPN transistor QN4 form a self-locking circuit. When the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are required to detect whether a human body is close, the control module only needs to output a short high-level signal to the base of the fourth NPN transistor QN4, the fourth NPN transistor QN4 is turned on, the second PNP transistor QP2 is turned on, the contactor K11 of the first relay K1 is attracted, and the control module can receive the electrical signal converted by the ultrasonic receiver LS2 in the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10.

[0071] When the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10 are not required to detect whether a human body is close, the control module only needs to output a short low-level signal to the base of the fourth NPN transistor QN4, the fourth NPN transistor QN4 is turned off, the second PNP transistor QP2 is turned off, the contactor K11 of the first relay K1 is disconnected, and the control module cannot receive the electrical signal converted by the ultrasonic receiver LS2 in the first ultrasonic sensor 8, the second ultrasonic sensor 9 and the third ultrasonic sensor 10.

[0072] According to some embodiments, the automatic protection system further comprises a lifting motor drive circuit, a first translation motor drive circuit and a second translation motor drive circuit which have the same circuit structure, the lifting motor drive circuit is connected to control the lifting control motor 204, the first translation motor drive circuit is connected to control the first translation control motor 303, and the second translation motor drive circuit is connected to control the second translation control motor 402.

[0073] As shown in Figure 7 The lifting motor drive circuit comprises a fifth NPN transistor QN5, a sixth NPN transistor QN6, a second relay K2, a third relay K3, a third diode D3, a fourth diode D4, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24 and a twenty-fifth resistor R25, and the specific connection mode is as follows,

[0074] The collector of the fifth NPN transistor QN5 is connected to one end of the coil of the second relay K2 and the anode of the third diode D3. The cathode of the third diode D3 is connected to the other end of the coil of the second relay K2 and one end of the twenty-second resistor R22. The other end of the twenty-second resistor R22 is connected to the DC power supply. The base of the fifth NPN transistor QN5 is connected to one end of the twenty-first resistor R21 and the control module via the twentieth resistor R20. The emitter of the fifth NPN transistor QN5 is connected to the other end of the twenty-first resistor R21. A collector of a sixth NPN transistor QN6 is connected to one end of the coil of the third relay K3 and the anode of the fourth diode D4. A cathode of the fourth diode D4 is connected to the other end of the coil of the third relay K3 and one end of a twenty-fifth resistor R25. The other end of the twenty-fifth resistor R25 is connected to a DC power supply. A base of the sixth NPN transistor QN6 is connected to one end of a twenty-fourth resistor R24 ​​and the control module via a twenty-third resistor R23. An emitter of the sixth NPN transistor QN6 is connected to the other end of the twenty-fourth resistor R24.

[0075] One end of the first contactor K21 of the second relay K2 is connected to the live wire, one end of the first contactor K31 of the third relay K3 is connected to the neutral wire, the other end of the first contactor K21 of the second relay K2 and the other end of the first contactor K31 of the third relay K3 are connected to the first electrode of the lifting control motor 204, one end of the second contactor K22 of the second relay K2 is connected to the neutral wire, one end of the second contactor K32 of the third relay K3 is connected to the live wire, and the other end of the second contactor K22 of the second relay K2 and the other end of the second contactor K32 of the third relay K3 are connected to the second electrode of the lifting control motor 204.

[0076] The working principle of the above embodiment is that when the cutter head 7 needs to be raised, the lifting control motor 204 is required to control the slidable bracket 203 to be raised, and the raising of the slidable bracket 203 can drive the cutter head 7 to be raised. When the lifting control motor 204 is required to control the slidable bracket 203 to be raised, the control module outputs a high-level signal to the base of the fifth NPN transistor QN5 and does not output a high-level signal to the base of the sixth NPN transistor QN6. The base of the sixth NPN transistor QN6 is grounded through the twenty-fourth resistor R24, the sixth NPN transistor QN6 is turned off, the fifth NPN transistor QN5 is turned on, the first contactor K21 and the second contactor K22 of the second relay K2 are energized, the first contactor K31 and the second contactor K32 of the third relay K3 are opened, and the lifting control motor 204 rotates forward, controlling the slidable bracket 203 to be raised.

[0077] When the tool bit 7 needs to be lowered, the slidable support 203 is lowered by controlling the lifting control motor 204. The control module outputs a high level signal to the base of the sixth NPN transistor QN6 and does not output a high level signal to the base of the fifth NPN transistor QN5, the base of the fifth NPN transistor QN5 is grounded through the twenty-first resistor R11, the fifth NPN transistor QN5 is cut off, the sixth NPN transistor QN6 is turned on, the first contactor K31 and the second contactor K32 of the third relay K3 are attracted, the first contactor K21 and the second contactor K22 of the second relay K2 are disconnected, the lifting control motor 204 is reversed, and the slidable support 203 is lowered.

[0078] According to some embodiments, as shown in FIG. 6, the spindle drive circuit includes a seventh NPN transistor QN7, a fourth relay K4, a fifth diode D5, a twenty-sixth resistor R26, a twenty-seventh resistor R27, and a twenty-eighth resistor R28, which are connected as follows, Figure 8

[0079] The base of the seventh NPN transistor QN7 is connected to the one end of the twenty-seventh resistor R27 and the control module through the twenty-sixth resistor R26, the collector of the seventh NPN transistor QN7 is connected to one end of the coil of the fourth relay K4 and the positive electrode of the fifth diode D5, the negative electrode of the fifth diode D5 is connected to the other end of the coil of the fourth relay K4 and one end of the twenty-eighth resistor R28, the other end of the twenty-eighth resistor R28 is connected to the DC power supply, the emitter of the seventh NPN transistor QN7 and the other end of the twenty-seventh resistor R27 are grounded, one end of the first contactor K41 of the fourth relay K4 is connected to the live wire, one end of the second contactor K42 of the fourth relay K4 is connected to the zero line, the other end of the first contactor K41 and the other end of the second contactor K42 of the fourth relay K4 are respectively connected to the two electrodes of the spindle motor 6.

[0080] The working principle of the above embodiment is that when the spindle motor 6 needs to work, the control module outputs a high level signal to the base of the seventh NPN transistor QN7 through the twenty-sixth resistor R26, the seventh NPN transistor QN7 is turned on, the first contactor K41 and the second contactor K42 of the fourth relay K4 are attracted, and the spindle motor 6 is powered on to work. When the spindle motor 6 needs to stop working, the control module does not output a high level signal to the base of the seventh NPN transistor QN7, the base of the seventh NPN transistor QN7 receives a low level signal through the twenty-sixth resistor R26 and the twenty-seventh resistor R27, the seventh NPN transistor QN7 is cut off, the first contactor K41 and the second contactor K42 of the fourth relay K4 are disconnected, and the spindle motor 6 is powered off to stop working.

[0081] ​In the description of the foregoing embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0082] While the disclosure has been described with reference to several exemplary embodiments, it is to be understood that the use of certain specific terminology or description does not limit the scope of the disclosure. Because the disclosure is capable of taking many forms in its embodiment, the above description should not be construed as limiting the scope of the disclosure, and the above-described embodiments should be interpreted as illustrative and not limiting. Therefore, all changes and modifications that come within the spirit and scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. An automatic protection system for a CNC machine tool, characterized in that: The CNC machine tool comprises: A base, a lifting assembly and a first translation assembly, wherein the first translation assembly is arranged on the top of the base, and the first end of the lifting assembly is arranged on the top of the first end of the base; a second translation assembly, wherein the bottom of the second translation assembly is movably connected to the top of the first translation assembly, the upper end of the second translation assembly is provided with a fixing fixture, and the second end of the lifting assembly is provided above the fixing fixture; a spindle motor, the spindle motor being disposed at the top of the second end of the lifting assembly, the end of the spindle motor's shaft passing through the second end of the lifting assembly and disposed above the fixing fixture, the end of the spindle motor's shaft being connected to a cutter head; The automatic protection system comprises: A control module, a sensor and a spindle drive circuit, wherein the control module is connected to the sensor and the spindle drive circuit respectively, and the spindle drive circuit is connected to control the spindle motor; When the spindle motor is in working state and the sensor detects that a human body is approaching, the control module controls the spindle motor to stop working through the spindle drive circuit; The lifting assembly includes a fixed bracket, a lifting slide rail, a slidable bracket and a lifting control motor, the bottom of the fixed bracket is connected to the top of the first end of the base, the lifting slide rail is vertically arranged on the fixed bracket, the spindle motor is arranged on the top of the slidable bracket, the end of the rotating shaft of the spindle motor passes through the slidable bracket and is arranged above the fixed clamp, the slidable bracket is movably connected to the lifting slide rail, the lifting control motor is arranged on the top of the fixed bracket, and the rotating shaft of the lifting control motor is connected to control the movement of the slidable bracket; The first translation assembly includes a first translation rail, a support platform, and a first translation control motor. The first translation rail is arranged on the top of the base. The bottom of the support platform is movably connected to the first translation rail. The first translation control motor is arranged at one end of the first translation rail. The rotating shaft of the first translation control motor is connected to control the movement of the support platform. The second translation assembly includes a second translation rail and a second translation control motor, the second translation rail is arranged on the top of the support platform, the bottom of the fixing fixture is movably connected to the second translation rail, the second translation control motor is arranged at one end of the second translation rail, and the rotating shaft of the second translation control motor is connected to control the movement of the fixing fixture; The sensors include a first ultrasonic sensor, a second ultrasonic sensor, and a third ultrasonic sensor having the same structure, wherein the first ultrasonic sensor is disposed on the slidable bracket and is used to detect the front side of the base opposite to the first end of the base, and the second ultrasonic sensor and the third ultrasonic sensor are disposed on the outer side wall of the base and are used to detect the left and right sides of the base, respectively; The first ultrasonic sensor includes an ultrasonic transmitting circuit and an ultrasonic receiving circuit, the ultrasonic transmitting circuit includes an ultrasonic transmitter, a first NPN transistor, a first PNP transistor, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor, the collector of the first NPN transistor is connected to a DC power supply through the first resistor, the emitter of the first NPN transistor is connected to the emitter of the first PNP transistor and the first electrode of the ultrasonic transmitter, the collector of the first PNP transistor is grounded through the third resistor, the base of the first NPN transistor and the base of the first PNP transistor are connected to the control module through the second resistor, the second electrode of the ultrasonic transmitter is connected to one end of the fourth resistor and one end of the fifth resistor, the other end of the fourth resistor is connected to the DC power supply, and the other end of the fifth resistor is grounded; The ultrasonic receiving circuit includes an ultrasonic receiver, a second NPN transistor, a third NPN transistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor. The first electrode of the ultrasonic receiver is connected to the base of the second NPN transistor and one end of the sixth resistor, the second electrode of the ultrasonic receiver is grounded, the collector of the second NPN transistor is connected to the other end of the sixth resistor, one end of the first capacitor and one end of the seventh resistor, the other end of the seventh resistor is connected to a DC power supply, the emitter of the second NPN transistor is grounded, the other end of the first capacitor is connected to one end of the eighth resistor, one end of the ninth resistor and the base of the third NPN transistor, the collector of the third NPN transistor is connected to the other end of the eighth resistor, one end of the tenth resistor and the control module, the other end of the ninth resistor and the emitter of the third NPN transistor are grounded, and the other end of the tenth resistor is connected to a DC power supply.

2. The automatic protection system for CNC machine tools according to claim 1, characterized in that: The ultrasonic receiving circuit also includes an operational amplifier, an eleventh resistor, a twelfth resistor, a thirteenth resistor and a fourteenth resistor, the non-inverting input terminal of the operational amplifier is connected to one end of the eleventh resistor and one end of the twelfth resistor, the other end of the eleventh resistor is connected to the collector of the third NPN transistor, the other end of the twelfth resistor is connected to the output terminal of the operational amplifier and one end of the thirteenth resistor, the inverting input terminal of the operational amplifier is grounded through the fourteenth resistor, and the other end of the thirteenth resistor is connected to the control module.

3. The automatic protection system for a CNC machine tool according to claim 2, characterized in that: The ultrasonic receiving circuit also includes a first diode and a fifteenth resistor, the positive electrode of the first diode is connected to the other end of the thirteenth resistor, the negative electrode of the first diode is connected to one end of the fifteenth resistor, the second ultrasonic sensor, the third ultrasonic sensor and the control module, and the other end of the fifteenth resistor is grounded.

4. The automatic protection system for a CNC machine tool according to claim 3, characterized in that: The automatic protection system also includes a detection switch circuit, which includes a fourth NPN transistor, a first relay, a second diode, a sixteenth resistor, a seventeenth resistor and an eighteenth resistor. The collector of the fourth NPN transistor is connected to one end of the coil end of the first relay and the positive electrode of the second diode, the negative electrode of the second diode is connected to the other end of the coil end of the first relay and one end of the eighteenth resistor, the other end of the eighteenth resistor is connected to a DC power supply, one end of the contactor of the first relay is connected to the negative electrode of the first diode, the second ultrasonic sensor and the third ultrasonic sensor, the other end of the contactor of the first relay is connected to the control module, the base of the fourth NPN transistor is connected to one end of the seventeenth resistor and the control module through the sixteenth resistor, and the emitter of the fourth NPN transistor and the other end of the seventeenth resistor are grounded.

5. The automatic protection system for a CNC machine tool according to claim 4, characterized in that: The detection switch circuit also includes a second PNP transistor and a nineteenth resistor, the emitter of the second PNP transistor is connected to the DC power supply through the nineteenth resistor, the base of the second PNP transistor is connected to the collector of the fourth NPN transistor, and the base of the fourth NPN transistor is connected to the collector of the second PNP transistor through the sixteenth resistor.

6. The automatic protection system for a CNC machine tool according to claim 1, characterized in that: The automatic protection system further includes a lifting motor drive circuit, a first translation motor drive circuit, and a second translation motor drive circuit having the same circuit structure, wherein the lifting motor drive circuit is connected to control the lifting control motor, the first translation motor drive circuit is connected to control the first translation control motor, and the second translation motor drive circuit is connected to control the second translation control motor; The lifting motor drive circuit includes a fifth NPN transistor, a sixth NPN transistor, a second relay, a third relay, a third diode, a fourth diode, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor and a twenty-fifth resistor. The collector of the fifth NPN transistor is connected to one end of the coil end of the second relay and the positive electrode of the third diode. The negative electrode of the third diode is connected to the other end of the coil end of the second relay and one end of the twenty-second resistor. The other end of the twenty-second resistor is connected to a DC power supply. The base of the fifth NPN transistor is connected to the second relay through the twenty-first resistor. One end of a twenty-first resistor and the control module are connected, the emitter of the fifth NPN transistor and the other end of the twenty-first resistor are grounded, the collector of the sixth NPN transistor is connected to one end of the coil end of the third relay and the anode of the fourth diode, the cathode of the fourth diode is connected to the other end of the coil end of the third relay and one end of the twenty-fifth resistor, the other end of the twenty-fifth resistor is connected to a DC power supply, the base of the sixth NPN transistor is connected to one end of the twenty-fourth resistor and the control module via the twenty-third resistor, and the emitter of the sixth NPN transistor and the other end of the twenty-fourth resistor are grounded; One end of the first contactor of the second relay is connected to the live wire, one end of the first contactor of the third relay is connected to the neutral wire, the other end of the first contactor of the second relay and the other end of the first contactor of the third relay are connected to the first electrode of the lifting control motor, one end of the second contactor of the second relay is connected to the neutral wire, one end of the second contactor of the third relay is connected to the live wire, and the other end of the second contactor of the second relay and the other end of the second contactor of the third relay are connected to the second electrode of the lifting control motor.

7. The automatic protection system for a CNC machine tool according to claim 1, characterized in that: The spindle drive circuit includes a seventh NPN transistor, a fourth relay, a fifth diode, a twenty-sixth resistor, a twenty-seventh resistor and a twenty-eighth resistor. The base of the seventh NPN transistor is connected to one end of the twenty-seventh resistor and the control module through the twenty-sixth resistor. The collector of the seventh NPN transistor is connected to one end of the coil end of the fourth relay and the positive electrode of the fifth diode. The negative electrode of the fifth diode is connected to the other end of the coil end of the fourth relay and one end of the twenty-eighth resistor. The other end of the twenty-eighth resistor is connected to a DC power supply. The emitter of the seventh NPN transistor and the other end of the twenty-seventh resistor are grounded. One end of the first contactor of the fourth relay is connected to the live wire, one end of the second contactor of the fourth relay is connected to the neutral wire, and the other end of the first contactor of the fourth relay and the other end of the second contactor are respectively connected to the two electrodes of the spindle motor.

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