Gear detection circuit, gear detection method, gear monitoring method and electronic equipment

Abstract

The invention relates to the technical field of gear detection, and provides a gear detection circuit, a gear detection method, a gear monitoring method and electronic equipment. The gear detection circuit comprises a constant light emitting circuit used for emitting a light signal with constant illumination intensity; a space for sawteeth of the gear to pass through is formed between the photoelectric conversion circuit and the constant light-emitting circuit, the photoelectric conversion circuit comprises a first detection circuit comprising a first light sensor, and the first detection circuit is used for outputting a light sensing signal of the first light sensor and a first electric signal generated when the light sensing signal is shielded by the tooth thickness profile of the sawteeth; and / or a second detection circuit comprising a second photosensitive element array, wherein the second detection circuit is used for outputting a second photosensitive element array sensing light signal and a second electric signal generated by being shielded by the end face projection of the sawteeth. The tooth thickness profile and the end face projection of the sawteeth are detected through photoelectric induction, whether the sawteeth have defects such as abrasion and displacement or not is judged, and the health condition of the gear is accurately measured under the condition that the gear does not need to be disassembled.

Description

Technical Field

[0001] The present invention relates to the technical field of gear detection, and in particular to a gear detection circuit, a gear detection method, a gear monitoring method and electronic equipment. Background Art

[0002] During use, gears are prone to defects due to tooth wear and displacement, which can cause transmission failure. The current method for inspecting gears is usually to disassemble the gears and observe the teeth with the naked eye or measure the teeth with a caliper. The current method requires the gears to be disassembled, and the disassembly process is not only time-consuming, but also easy to damage the gears; in addition, the naked eye method cannot objectively evaluate the condition of the gears, and the caliper measurement method will limit the measurement accuracy due to the caliper precision.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0004] In view of this, the present invention provides a gear detection circuit, a gear detection method, a gear monitoring method and an electronic device, which detect the tooth thickness profile and end face projection of the sawtooth through photoelectric sensing, thereby determining whether the sawtooth has defects such as wear and displacement, and accurately measuring the health status of the gear without disassembling the gear, thereby providing a basis for ensuring the gear transmission performance.

[0005] According to one aspect of the present invention, there is provided a gear detection circuit, comprising: a constant light emitting circuit, comprising a light source for emitting a light signal with a constant light intensity; a photoelectric conversion circuit, comprising: a first detection circuit, comprising at least one first photosensitive element, the first photosensitive element being located within the illumination range of the light source, a first space being formed between the first photosensitive element and the light source for the sawtooth of the gear to pass through, the first detection circuit being used to output a first electrical signal generated by the first photosensitive element sensing the light signal and being blocked by the tooth thickness profile of the sawtooth; wherein the first photosensitive element comprises a plurality of first photosensitive elements, and the plurality of first photosensitive elements are arranged along the tooth height direction of the sawtooth; when the corresponding sawtooth passes through the first space, the tooth thickness profiles at each tooth height position of the sawtooth respectively block the corresponding sawtooth. The light source illuminates the light signals of the plurality of the first photosensitive elements, and the first detection circuit outputs a first electrical signal representing the distance between the tooth profiles at each tooth height position of the sawtooth; and / or, a second detection circuit includes a second photosensitive element array, the second photosensitive element array is located within the illumination range of the light source, a second space for the sawtooth to pass through is formed between the second photosensitive element array and the light source, and the second detection circuit is used to output a second electrical signal generated by the second photosensitive element array sensing the light signal and being blocked by the end face projection of the sawtooth; wherein, when the corresponding sawtooth passes through the second space, the light source illuminates the end face of the sawtooth and projects onto the second photosensitive element array, and the second detection circuit outputs a second electrical signal representing the end face area of ​​the sawtooth.

[0006] The constant light-emitting circuit emits a light signal with constant light intensity, providing a stable input for the photoelectric conversion circuit, ensuring the accuracy of the detection result of the photoelectric conversion circuit. The photoelectric conversion circuit and the constant light-emitting circuit are set to leave space for the sawtooth to pass through, so there is no need to disassemble the gears during detection, and the gears can be operated. The first photosensitive element is located in the illumination range of the light source, and a first space for the sawtooth to pass through is formed between the first photosensitive element and the light source; when no sawtooth passes through the first space, the first photosensitive element senses the light signal; when a sawtooth passes through the first space, the tooth thickness profile of the sawtooth blocks the light signal, and the first electrical signal generated by the first photosensitive element changes; in this way, the parameters related to the tooth thickness profile of the sawtooth can be detected through the change of the first electrical signal output by the first detection circuit. The second photosensitive element array is located within the illumination range of the light source, and forms a second space for the sawtooth to pass through between the second photosensitive element array and the light source; when no sawtooth passes through the second space, the second photosensitive element array completely receives the light signal; when a sawtooth passes through the second space, the end face of the sawtooth is projected onto the second photosensitive element array by the light signal, causing the second electrical signal generated by the second photosensitive element blocked by the projection of the end face of the sawtooth to change; in this way, the parameters related to the projection of the end face of the sawtooth can be detected through the change of the second electrical signal output by the second detection circuit.

[0007] The gear detection circuit of the present invention detects the tooth thickness profile and end face projection of the sawtooth through photoelectric sensing, thereby determining whether the sawtooth has defects such as wear and displacement, and accurately measures the health status of the gear without disassembling the gear, providing a basis for ensuring the gear transmission performance.

[0008] When no sawtooth passes through the first space, the first photosensitive element receives the light signal and outputs a high-level first electrical signal; when a sawtooth passes through the first space, the light signal is blocked by the tooth thickness profile of the sawtooth, and the first photosensitive element outputs a low-level first electrical signal; when the tooth thickness profile leaves the first space, the first photosensitive element receives the light signal again and outputs a high-level first electrical signal. In this way, according to the duration of the low-level first electrical signal and the running speed of the gear, the relevant parameters of the distance between the tooth profiles of the sawtooth can be obtained.

[0009] Multiple first photosensitive elements are arranged along the tooth height direction of the sawtooth, and can respectively detect the distance between the tooth profiles at different tooth height positions of the sawtooth; the more first photosensitive elements there are, the more accurately the tooth profile shape of the sawtooth can be fed back, making the detection result more precise.

[0010] When no sawtooth passes through the second space, each second photosensitive element in the second photosensitive element array receives the optical signal and outputs a high-level second electrical signal; when a sawtooth passes through the second space, the optical signal is partially blocked by the end surface projection of the sawtooth, and the blocked second photosensitive element in the second photosensitive element array outputs a low-level second electrical signal; when the end surface projection leaves the second space, each second photosensitive element outputs a high-level second electrical signal again. In this way, the relevant parameters of the end surface area of ​​the sawtooth can be obtained based on the second photosensitive element that outputs the low-level second electrical signal.

[0011] In some embodiments, the light source is a parallel light source; when the photoelectric conversion circuit includes the first detection circuit: the parallel light source vertically illuminates the first photosensitive element; when the corresponding sawtooth passes through the first space, the parallel light source, the sawtooth and the first photosensitive element are arranged along the tooth width direction of the sawtooth; when the photoelectric conversion circuit includes the second detection circuit: the parallel light source vertically illuminates the second photosensitive element array; when the corresponding sawtooth passes through the second space, the parallel light source, the sawtooth and the second photosensitive element array are arranged along the tooth width direction of the sawtooth.

[0012] The parallel light source vertically illuminates the first photosensitive element, and when detecting the distance between the tooth profiles of a sawtooth, the parallel light source, the sawtooth and the first photosensitive element are arranged along the tooth width direction of the sawtooth, so that the detection result accurately reflects the distance between the tooth profiles, thereby determining whether the sawtooth has defects such as wear and displacement, thereby ensuring the accuracy and reliability of the detection. The parallel light source vertically illuminates the second photosensitive element array, and when detecting the end face area of ​​a sawtooth, the parallel light source, the sawtooth and the second photosensitive element array are arranged along the tooth width direction of the sawtooth, so that the detection result accurately reflects the end face area, thereby determining whether the sawtooth has defects such as wear and displacement, thereby ensuring the accuracy and reliability of the detection.

[0013] In some embodiments, the constant light emitting circuit includes a negative feedback circuit, and the light source is connected to an output end of the negative feedback circuit.

[0014] The negative feedback circuit can stabilize the output voltage, thereby driving the light source to emit a light signal with constant light intensity.

[0015] In some embodiments, the negative feedback circuit includes: a first operational amplifier, a constant voltage is input to the non-inverting input terminal of the first operational amplifier; a first transistor, a control terminal of the first transistor is connected to the output terminal of the first operational amplifier; a first output loop, including the light source, the first transistor and a sampling resistor connected in series, and the series node of the sampling resistor and the first transistor is connected to the inverting input terminal of the first operational amplifier.

[0016] The first operational amplifier and the first transistor constitute the main part of the negative feedback circuit. The sampling resistor feeds back the current of the first output loop where the light source is located in real time. The current of the first output loop is kept constant through the regulation of the first operational amplifier and the first transistor, thereby driving the light source to emit a light signal with constant light intensity.

[0017] In some embodiments, the constant light-emitting circuit also includes a shaping circuit connected between the pulse signal input terminal and the in-phase input terminal of the first operational amplifier, and the shaping circuit includes: a first resistor and a second resistor in parallel, the first ends of the first resistor and the second resistor are respectively connected to the pulse signal input terminal, and the second end of the first resistor is grounded; a first capacitor and a second capacitor in parallel, the first ends of the first capacitor and the second capacitor are respectively connected to the second end of the second resistor and the in-phase input terminal of the first operational amplifier, and the second ends of the first capacitor and the second capacitor are respectively grounded.

[0018] The shaping circuit is used to shape the pulse signal into a stable DC voltage and provide it to the negative feedback circuit so that the negative feedback circuit can adjust and generate a stable current that drives the light source to emit light constantly.

[0019] In some embodiments, when the photoelectric conversion circuit includes the first detection circuit, the first detection circuit includes at least one first sub-detection circuit respectively including first photosensitive elements, and each of the first sub-detection circuits includes: a second operational amplifier, the first photosensitive element is connected between two input terminals of the second operational amplifier; a second output loop, including an optocoupler chip and a second transistor, the light-emitting element of the optocoupler chip is connected in series with the second transistor, the control terminal of the second transistor is connected to the output terminal of the second operational amplifier, and the photosensitive element of the optocoupler chip is connected to the output terminal of the first sub-detection circuit.

[0020] The potential difference generated at both ends of the first photosensitive element is amplified by the second operational amplifier, and the electrical signal change generated by the first photosensitive element being blocked by the tooth thickness profile of the sawtooth when the sawtooth passes through the first space is accurately collected, and the optocoupler chip is driven to work, so that the second output circuit outputs the first electrical signal that accurately represents the distance between the tooth profiles of the sawtooth.

[0021] In some embodiments, each of the first sub-detection circuits also includes any of the following electronic components: a second current limiting resistor, connected in series between the light-emitting element of the optocoupler chip and the second transistor; a third current limiting resistor, connected in series with the photosensitive element of the optocoupler chip; a pull-up resistor, connected between the power supply end and the output end of the second operational amplifier.

[0022] The current limiting resistor is used to provide current limiting protection in the corresponding loop. The pull-up resistor is used to stabilize the output of the second operational amplifier to avoid oscillation.

[0023] In some embodiments, when the photoelectric conversion circuit includes the second detection circuit, the second detection circuit includes a plurality of second sub-detection circuits each including a second photosensitive element, and each of the second sub-detection circuits includes: a third operational amplifier, the second photosensitive element is connected between two input terminals of the third operational amplifier; a third output loop, including a fourth current limiting resistor and a third transistor connected in series, the control terminal of the third transistor is connected to the output terminal of the third operational amplifier, and the series node of the fourth current limiting resistor and the third transistor is connected to the output terminal of the second sub-detection circuit.

[0024] The potential difference generated at both ends of the second photosensitive element is amplified by the third operational amplifier, and the electrical signal change caused by the second photosensitive element being blocked by the end surface projection of the sawtooth when the sawtooth passes through the second space is accurately collected, and the third output circuit is driven to work, so that the third output circuit outputs a second electrical signal that accurately represents the end surface area of ​​the sawtooth.

[0025] In some embodiments, when the photoelectric conversion circuit includes the first detection circuit: the first photosensitive element and the light source are arranged in a closed space, and the first space is located in the closed space; when the photoelectric conversion circuit includes the second detection circuit: the second photosensitive element array and the light source are arranged in a closed space, and the second space is located in the closed space.

[0026] In this way, the optical signal transmission between the electronic components is ensured to be stable, thereby ensuring the accurate detection of the distance between the tooth profiles and the end surface area of ​​the sawtooth.

[0027] According to another aspect of the present invention, there is provided a gear detection method, which is implemented based on the gear detection circuit as described in any of the above embodiments, including: arranging a gear between the constant light-emitting circuit and the photoelectric conversion circuit, controlling the gear operation so that each sawtooth of the gear passes through the illumination range of the constant light-emitting circuit in turn; obtaining a detection result of each sawtooth of the gear according to an electrical signal output by the photoelectric conversion circuit, including: when the photoelectric conversion circuit includes a first detection circuit: obtaining first detection data characterizing the distance between the tooth profiles of each sawtooth according to a first electrical signal output by the first detection circuit, and obtaining a first detection result of whether the corresponding sawtooth is faulty according to the first detection data; when the photoelectric conversion circuit includes a second detection circuit: obtaining second detection data characterizing the end face area of ​​each sawtooth according to a second electrical signal output by the second detection circuit, and obtaining a second detection result of whether the corresponding sawtooth is faulty according to the second detection data.

[0028] The parameters related to the distance between the tooth profiles and the end surface area of ​​the sawtooth can effectively reflect whether the sawtooth, especially the tooth surface of the sawtooth, has defects such as wear and displacement that affect the transmission performance. The gear detection circuit of the present invention detects the tooth thickness profile and end surface projection of the sawtooth through photoelectric sensing, and determines whether the sawtooth has defects such as wear and displacement. The health status of the gear can be accurately measured without disassembling the gear, providing a basis for ensuring the transmission performance of the gear.

[0029] In some embodiments, when the gear is a gear that performs rotational motion, the first detection data representing the distance between tooth profiles of each sawtooth is obtained, including: calculating the distance L between tooth profiles at a tooth height position of a sawtooth. AB , , wherein the initial tooth profile distance at the tooth height position of the sawtooth and the center point of the gear form an isosceles triangle, L OB is the waist length of the isosceles triangle, w is the speed of the gear, t 1 It is the time that the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile at the tooth height position.

[0030] In the initial stage of the gear being put into use, the distance between the tooth profiles at each tooth height position of the sawtooth and the center point of the gear form an isosceles triangle, and the distance between the tooth profiles at each tooth height position is detected by the first photosensitive element correspondingly set at each tooth height position. OB , that is, the distance between the tooth profile point B and the gear center point O, is a known parameter of the gear; combined with the gear speed w and the time t that the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile at the tooth height position 1 , use the Pythagorean theorem to calculate the distance L between the tooth profiles at the tooth height position of the sawtooth AB .

[0031] In some embodiments, obtaining a first detection result of whether the corresponding sawtooth is faulty based on the first detection data includes: comparing the first detection data of each sawtooth with a first abnormal reference range and / or a first fault reference range; when the first detection data of a sawtooth falls into the first abnormal reference range, determining that the sawtooth is abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, determining that the sawtooth is faulty; when the first detection data of a sawtooth falls into the first fault reference range, determining that the sawtooth is faulty.

[0032] When the first detection data of a sawtooth falls into the first abnormal reference range, it indicates that the distance between the tooth profiles of the sawtooth is abnormal, and the sawtooth may be faulty; to avoid errors caused by a single test, when a sawtooth is determined to be abnormal for multiple consecutive times, the sawtooth is determined to be faulty. When the first detection data of a sawtooth falls into the first fault reference range, it indicates that the distance between the tooth profiles of the sawtooth has seriously deviated from the initial value, and therefore the sawtooth is determined to be faulty.

[0033] In some embodiments, the obtaining of second detection data characterizing the end face area of ​​each sawtooth includes: when the corresponding sawtooth passes through the second space, determining the blocked second photosensitivity element according to the electrical signal output by each second photosensitivity element in the second photosensitivity element array; and determining the end face area of ​​the sawtooth according to the blocked second photosensitivity element.

[0034] The light source, the sawtooth to be detected and the second photosensitive element array can be arranged along the tooth width direction of the sawtooth to be detected, and the second photosensitive element array can be consistent with the initial size of the sawtooth in the tooth thickness direction, so as to facilitate the detection of the end surface area of ​​the sawtooth. When a sawtooth passes through the second space, the end surface of the sawtooth is projected onto the second photosensitive element array by the light signal, and the end surface area of ​​the sawtooth can be determined based on the area of ​​the second photosensitive element blocked by the projection of the end surface of the sawtooth.

[0035] In some embodiments, obtaining a second detection result of whether the corresponding sawtooth is faulty based on the second detection data includes: comparing the second detection data of each sawtooth with a second abnormal reference range and / or a second fault reference range; when the second detection data of a sawtooth falls into the second abnormal reference range, determining that the sawtooth is abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, determining that the sawtooth is faulty; when the second detection data of a sawtooth falls into the second fault reference range, determining that the sawtooth is faulty.

[0036] When the second detection data of a sawtooth falls into the second abnormal reference range, it indicates that the end surface area of ​​the sawtooth is abnormal and the sawtooth may be faulty; to avoid errors caused by a single test, when a sawtooth is determined to be abnormal for multiple consecutive times, the sawtooth is determined to be faulty. When the second detection data of a sawtooth falls into the second fault reference range, it indicates that the end surface area of ​​the sawtooth has seriously deviated from the initial value, so the sawtooth is determined to be faulty.

[0037] In some embodiments, when the photoelectric conversion circuit includes the first detection circuit, if the first detection result indicates more than two sawtooth faults; and / or, when the photoelectric conversion circuit includes the second detection circuit, if the second detection result indicates more than two sawtooth faults; and / or, when the photoelectric conversion circuit includes the first detection circuit and the second detection circuit, if the first detection result and the second detection result indicate the same sawtooth fault; then, the gear fault is determined.

[0038] Failure of more than two saw teeth or serious abnormalities of multiple parameters of the same saw tooth will seriously affect the transmission performance of the gear, so gear failure is determined.

[0039] According to another aspect of the present invention, there is provided a gear monitoring method for an electric power steering system, which is implemented based on the gear detection method as described in any of the above embodiments, and includes: when the detection result indicates at least one sawtooth fault, issuing an alarm containing the detection result; when the vehicle is ignited next time, if the alarm is not eliminated, controlling the electric power steering system to refuse to provide assistance.

[0040] Based on the above-mentioned gear detection method, the gears of the electric power steering system are detected. The tooth profile and end face of the sawtooth during the operation of the gear are detected by photoelectric sensing to monitor whether the sawtooth has defects such as wear and displacement. When a sawtooth fault is detected, the driver is promptly reminded to take countermeasures, thereby improving the reliability and safety of the electric power steering system.

[0041] According to another aspect of the present invention, an electronic device is provided, wherein the electronic device stores a program, and when the program is executed by a processor, the method described in any of the above embodiments is implemented.

[0042] In some embodiments, the electronic device further comprises a processor for executing the program.

[0043] The beneficial effects of the present invention compared with the prior art include at least: The gear detection scheme of the present invention detects the tooth profile and end face of the sawtooth through photoelectric sensing, thereby determining whether the sawtooth has defects such as wear and displacement. The health status of the gear can be accurately measured without disassembling the gear, providing a basis for ensuring the gear transmission performance.

[0044] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification are used to explain the principles of the present invention. Obviously, the accompanying drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0046] Figure 1 A schematic diagram showing the structure of a gear detection circuit in an embodiment of the present invention is shown; Figure 2 A schematic diagram showing the structure of a gear; Figure 3 A schematic diagram showing the structure of a constant light emitting circuit in an embodiment of the present invention is shown; Figure 4 A schematic diagram showing the structure of a first detection circuit in an embodiment of the present invention is shown; Figure 5 A schematic diagram showing the structure of a second detection circuit in an embodiment of the present invention is shown; Figure 6 A schematic diagram showing the steps of a gear detection method according to an embodiment of the present invention; Figure 7 A schematic diagram showing the end face shape of a sawtooth; Figure 8 A schematic diagram showing the steps of a gear monitoring method for an electric power steering system according to an embodiment of the present invention; Fig. 9 A schematic diagram showing the structure of an electronic device in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0047] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments described herein. Instead, these embodiments are provided to make the present invention more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art.

[0048] The accompanying drawings are only schematic illustrations of the present invention and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0049] The processes shown in the accompanying drawings are only exemplary and do not necessarily include all the steps. For example, some steps can be decomposed, some steps can be combined or partially combined, and the actual execution order may change according to the actual situation. The words "first", "second" and similar words used in the specific description do not indicate any order, quantity or importance, but are only used to distinguish different components. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined. In addition, when it is said that a device is "connected" to another device, this includes not only the case of direct connection, but also the case of indirect connection through other elements.

[0050] It should be noted that, in the absence of conflict, the embodiments of the present invention and features in different embodiments may be combined with each other.

[0051] Figure 1 The schematic diagram shows the architecture module of the gear detection circuit, refer to Figure 1 As shown, the gear detection circuit provided by the embodiment of the present invention includes: The constant light emitting circuit 110 comprises a light source LED1 for emitting a light signal with a constant light intensity; The photoelectric conversion circuit 120 includes: a first detection circuit 120a, including at least one first photosensitive element PD, the first photosensitive element PD is located in the illumination range of the light source LED1, and a first space 100a for the sawtooth of the gear to pass through is formed between the first photosensitive element PD and the light source LED1, and the first detection circuit 120a is used to output the light signal sensed by the first photosensitive element PD and the first electrical signal generated by being blocked by the tooth thickness profile of the sawtooth; and / or, a second detection circuit 120b, including a second photosensitive element PT1 array, the second photosensitive element PT1 array is located in the illumination range of the light source LED1, and a second space 100b for the sawtooth to pass through is formed between the second photosensitive element PT1 array and the light source LED1, and the second detection circuit 120b is used to output the light signal sensed by the second photosensitive element PT1 array and the second electrical signal generated by being blocked by the end surface projection of the sawtooth.

[0052] The constant light-emitting circuit 110 emits a light signal with constant illumination intensity, providing a stable input for the photoelectric conversion circuit 120, ensuring that the detection result of the photoelectric conversion circuit 120 is accurate. The photoelectric conversion circuit 120 and the constant light-emitting circuit 110 are set to leave space for the sawtooth to pass through, so there is no need to disassemble the gear during detection, and the gear can be operated. The first photosensitive element PD is located in the illumination range of the light source LED1, and forms a first space 100a for the sawtooth to pass through between the first photosensitive element PD and the light source LED1; when no sawtooth passes through the first space 100a, the first photosensitive element PD senses the light signal; when a sawtooth passes through the first space 100a, the tooth thickness profile of the sawtooth blocks the light signal, and the first electrical signal generated by the first photosensitive element PD changes; in this way, the parameters related to the tooth thickness profile of the sawtooth can be detected through the change of the first electrical signal output by the first detection circuit 120a. For example, according to the duration of the changed first electrical signal and the running speed of the gear, the relevant parameters of the distance between the tooth profiles of the sawtooth can be obtained. The second photosensitive element PT1 array is located within the illumination range of the light source LED1, and forms a second space 100b for the sawtooth to pass through with the light source LED1; when no sawtooth passes through the second space 100b, the second photosensitive element PT1 array completely receives the light signal; when a sawtooth passes through the second space 100b, the end face of the sawtooth is projected to the second photosensitive element PT1 array by the light signal, causing the second electrical signal generated by the second photosensitive element PT1 blocked by the end face projection of the sawtooth to change; in this way, the parameters related to the end face projection of the sawtooth can be detected through the change of the second electrical signal output by the second detection circuit 120b. For example, according to the changed second electrical signal, the second photosensitive element PT1 blocked by the end face projection is determined, and then the parameters related to the end face area of ​​the sawtooth are determined according to the blocked second photosensitive element PT1. The parameters related to the distance between the tooth profiles and the end face area of ​​the sawtooth can effectively reflect whether the sawtooth, especially the tooth surface of the sawtooth, has defects such as wear and displacement that affect the transmission performance.

[0053] The gear detection circuit of the present invention detects the tooth thickness profile and end face projection of the sawtooth through photoelectric sensing, thereby determining whether the sawtooth has defects such as wear and displacement, and accurately measures the health status of the gear without disassembling the gear, providing a basis for ensuring the gear transmission performance.

[0054] Figure 2 The structure of the gear is shown in figure. Figure 1 and Figure 2As shown, the gear 200 includes a main body 210 and a sawtooth 220 formed on the main body 210, and the sawtooth 220 is defined by parameters such as tooth surface, tooth profile, tooth thickness, tooth height, tooth width, and end face. The tooth thickness profile refers to the contour line that forms the tooth thickness of the sawtooth 220, and the distance between tooth profiles refers to the straight-line distance between the tooth profiles of the sawtooth 220. During detection, the light source LED1, the sawtooth 220 to be detected, and the first photosensitive element PD / second photosensitive element PT1 array can form a structure arranged along the tooth width direction of the sawtooth 220 to be detected, so as to achieve accurate detection of the tooth thickness profile and end face projection of the sawtooth 220. It should be noted that the main body 210 of the gear 200 also has an axial hole in the middle part, Figure 2 Not specifically shown.

[0055] The gear detection scheme of the present invention is suitable for detecting spur gears and slightly inclined helical gears; if the sawtooth inclination is too large, it may not be possible to accurately measure due to the interlacing of the teeth on the end faces, but it can also be used as an auxiliary measurement when necessary. The gears referred to in the present invention include internal gears and external gears, and are not limited to Figure 2 The gears shown have serrations formed on the wheel rim, and also include special gears such as racks, worm wheels, and worms.

[0056] Continue to combine Figure 1 and Figure 2 As shown, in some embodiments, when the photoelectric conversion circuit 120 includes a first detection circuit 120a: when the corresponding sawtooth 220 passes through the first space 100a, the tooth thickness profile of the sawtooth 220 blocks the light signal of the light source LED1 irradiating the first photosensitive element PD, and the first detection circuit 120a outputs a first electrical signal representing the distance between the tooth profiles of the sawtooth 220.

[0057] The running track of the gear 200 is, for example, along the circumferential direction R0. When no sawtooth 220 passes through the first space 100a, the first photosensitive element PD receives the optical signal and outputs a high-level first electrical signal; when a sawtooth 220 passes through the first space 100a, the optical signal is blocked by the tooth thickness profile of the sawtooth 220, and the first photosensitive element PD outputs a low-level first electrical signal; when the tooth thickness profile leaves the first space 100a, the first photosensitive element PD receives the optical signal again and outputs a high-level first electrical signal. In this way, according to the duration of the low-level first electrical signal and the running speed of the gear 200, the relevant parameters of the distance between the tooth profiles of the sawtooth 220 can be obtained.

[0058] The first detection circuit 120a may directly output the first electrical signal generated by the first photosensitive element PD, or may process the first electrical signal generated by the first photosensitive element PD and then output it.

[0059] In some embodiments, the first photosensitive element PD includes multiple first photosensitive elements PD, and the multiple first photosensitive elements PD are arranged along the tooth height direction of the sawtooth 220; when the corresponding sawtooth 220 passes through the first space 100a, the tooth thickness contours at each tooth height position of the sawtooth 220 respectively block the light signals of the light source LED1 irradiating the multiple first photosensitive elements PD, and the first detection circuit 120a outputs a first electrical signal representing the distance between the tooth profiles at each tooth height position of the sawtooth 220.

[0060] Multiple first photosensitive elements PD are arranged along the tooth height direction of the sawtooth 220, and can respectively detect the distance between the tooth profiles of the sawtooth 220 at different tooth height positions; the more the number of first photosensitive elements PD is, the more accurately the tooth profile shape of the sawtooth 220 can be fed back, making the detection result more precise.

[0061] Continue to combine Figure 1 and Figure 2 As shown, in some embodiments, when the photoelectric conversion circuit 120 includes a second detection circuit 120b: when the corresponding sawtooth 220 passes through the second space 100b, the light source LED1 illuminates the end face of the sawtooth 220 and projects it onto the second photosensitive element PT1 array, and the second detection circuit 120b outputs a second electrical signal representing the end face area of ​​the sawtooth 220.

[0062] When no sawtooth 220 passes through the second space 100b, each second photosensitive element PT1 in the second photosensitive element PT1 array receives the optical signal and outputs a high-level second electrical signal; when a sawtooth 220 passes through the second space 100b, the optical signal is partially blocked by the end surface projection of the sawtooth 220, and the blocked second photosensitive element PT1 in the second photosensitive element PT1 array outputs a low-level second electrical signal; when the end surface projection leaves the second space 100b, each second photosensitive element PT1 outputs a high-level second electrical signal again. In this way, the relevant parameters of the end surface area of ​​the sawtooth 220 can be obtained based on the second photosensitive element PT1 that outputs the low-level second electrical signal.

[0063] The second detection circuit 120b may directly output the second electrical signal generated by the second photosensitive element PT1, or may process the second electrical signal generated by the second photosensitive element PT1 and then output it.

[0064] The principle of using the first detection circuit 120a to detect the distance between the tooth profiles of the sawtooth 220 is similar to the principle of using the second detection circuit 120b to detect the end surface area of ​​the sawtooth 220, with the difference being that each first photosensitive element PD forms a "detection point", and when the sawtooth 220 passes through the first space 100a, the optical signal for the first photosensitive element PD is blocked by the tooth thickness profile of the sawtooth 220, so that the first detection circuit 120a detects the linear distance between the tooth profiles; the second photosensitive element PT1 array forms a "detection surface", and when the sawtooth 220 passes through the second space 100b, for the second photosensitive element PT1 array, part of the optical signal received by the second photosensitive element PT1 is blocked by the end surface projection of the sawtooth 220, so that the second detection circuit 120b detects the end surface area of ​​the surface shape.

[0065] In some embodiments, the light source LED1 is a parallel light source; when the photoelectric conversion circuit 120 includes a first detection circuit 120a: the parallel light source vertically illuminates the first photosensitive element PD; when the corresponding sawtooth 220 passes through the first space 100a, the parallel light source, the sawtooth 220 and the first photosensitive element PD are arranged along the tooth width direction of the sawtooth 220; when the photoelectric conversion circuit 120 includes a second detection circuit 120b: the parallel light source vertically illuminates the second photosensitive element PT1 array; when the corresponding sawtooth 220 passes through the second space 100b, the parallel light source, the sawtooth 220 and the second photosensitive element PT1 array are arranged along the tooth width direction of the sawtooth 220.

[0066] The parallel light source vertically illuminates the first photosensitive element PD / second photosensitive element PT1 array, and when detecting the distance between tooth profiles / end face area of ​​a sawtooth 220, the parallel light source, sawtooth 220 and the first photosensitive element PD / second photosensitive element PT1 array are arranged along the tooth width direction of the sawtooth 220, so that the detection result accurately reflects the distance between tooth profiles / end face area, thereby determining whether the sawtooth 220 has defects such as wear and displacement, thereby ensuring the accuracy and reliability of the detection.

[0067] Figure 1 The gear detection circuit of the present invention shown can be assembled together with the gear in the transmission system. In the initial stage of the gear being put into use, the initial first electrical signal representing the distance between the tooth profiles of each sawtooth / the initial second electrical signal representing the end surface area of ​​each sawtooth can be recorded; with use, when the change of the first electrical signal representing the distance between the tooth profiles of a sawtooth / the second electrical signal representing the end surface area of ​​a sawtooth exceeds the set range, it can be considered that the sawtooth has defects such as wear and displacement that will affect its transmission performance.

[0068] In some implementation scenarios, due to spatial layout limitations, the light source LED1 may also obliquely illuminate the first photosensitive element PD / second photosensitive element PT1 array; at this time, the obtained detection result does not directly reflect the distance between the tooth profiles / end face area of ​​the sawtooth, but it is still possible to determine whether the sawtooth has defects such as wear and displacement that may affect its transmission performance by judging whether "with use, the change in the first electrical signal representing the distance between the tooth profiles of a sawtooth / the second electrical signal representing the end face area of ​​a sawtooth exceeds a set range".

[0069] Figure 3 The structure of the constant light emitting circuit is shown; combined with Figure 1 and Figure 3 As shown, in some embodiments, the constant light emitting circuit 110 includes a negative feedback circuit 111 , and the light source LED1 is connected to the output end of the negative feedback circuit 111 .

[0070] The negative feedback circuit 111 can stabilize the output voltage, thereby driving the light source LED1 to emit a light signal with constant light intensity. In other embodiments, in addition to the negative feedback circuit 111, a filter circuit, a voltage stabilizing circuit, etc. can also be used to drive the light source LED1 to emit a light signal with constant light intensity.

[0071] In some embodiments, the negative feedback circuit 111 includes: a first operational amplifier U1, a constant voltage is input to the non-inverting input terminal of the first operational amplifier U1; a first transistor Q1, a control terminal of the first transistor Q1 is connected to the output terminal of the first operational amplifier U1; a first output loop, including a light source LED1, a first transistor Q1 and a sampling resistor R3 connected in series, and the series node of the sampling resistor R3 and the first transistor Q1 is connected to the inverting input terminal of the first operational amplifier U1.

[0072] The first operational amplifier U1 and the first transistor Q1 form the main part of the negative feedback circuit 111, and the sampling resistor R3 feeds back the current of the first output circuit where the light source LED1 is located in real time (the power supply voltage of the first output circuit is Vcc). The current of the first output circuit is constant through the regulation of the first operational amplifier U1 and the first transistor Q1, thereby driving the light source LED1 to emit a light signal with constant illumination intensity. Among them, the light source LED1 can be a light emitting diode, but is not limited to this. When the current of the first output circuit increases, the voltage of the inverting input terminal of the first operational amplifier U1 becomes higher, and the difference between it and the inverting input terminal becomes smaller, then the differential voltage value output by the first operational amplifier U1 becomes smaller, resulting in a smaller current controlling the base of the first transistor Q1, thereby increasing the internal resistance of the first transistor Q1, increasing the voltage drop between the emitter and the collector, and reducing the current of the first output circuit. When the current of the first output loop decreases, the voltage of the inverting input terminal of the first operational amplifier U1 decreases, and the difference between the inverting input terminal and the non-inverting input terminal increases, then the differential voltage value output by the first operational amplifier U1 increases, resulting in an increase in the current controlling the base of the first transistor Q1, thereby reducing the internal resistance of the first transistor Q1, reducing the voltage drop between the emitter and the collector, and increasing the current of the first output loop. In this way, the current of the first output loop is fed back in real time by the sampling resistor R3 and regulated by the first operational amplifier U1 and the first transistor Q1, and finally reaches a constant stable current.

[0073] In some embodiments, the negative feedback circuit 111 further includes a first current limiting resistor R4 connected in series between the output terminal of the first operational amplifier U1 and the base of the first transistor Q1, ie, the control terminal. The first current limiting resistor R4 provides current limiting protection for the first transistor Q1.

[0074] In some embodiments, the constant light-emitting circuit 110 also includes a shaping circuit 112 connected between the pulse signal input terminal IN and the in-phase input terminal of the first operational amplifier U1, and the shaping circuit 112 includes: a first resistor R1 and a second resistor R2 in parallel, the first ends of the first resistor R1 and the second resistor R2 are respectively connected to the pulse signal input terminal IN, and the second end of the first resistor R1 is grounded; a first capacitor C1 and a second capacitor C2 in parallel, the first ends of the first capacitor C1 and the second capacitor C2 are respectively connected to the second end of the second resistor R2 and the in-phase input terminal of the first operational amplifier U1, and the second ends of the first capacitor C1 and the second capacitor C2 are respectively grounded.

[0075] The shaping circuit 112 is used to shape the pulse signal into a stable DC voltage and provide it to the negative feedback circuit 111 so that the negative feedback circuit 111 can adjust and generate a stable current that drives the light source LED1 to emit light constantly. The shaping circuit 112 can quickly and stably shape the pulse signal input from the pulse signal input terminal IN into a DC voltage through the large capacitance charging and discharging characteristics of the first capacitor C1 and the second capacitor C2, in conjunction with the first resistor R1 and the second resistor R2. Among them, when the gear detection scheme is applied to the vehicle, the pulse signal can be a rectangular wave with a duty cycle of N and a peak value of U transmitted from the central processing unit (CPU) port; after the shaping process of the shaping circuit 112, the rectangular wave gradually becomes DC, and the DC voltage amplitude is (U×N)V. The DC voltage is output to the above-mentioned negative feedback circuit 111, and the current that drives the light source LED1 to emit light constantly can be obtained as: I=(U×N)÷R3.

[0076] Figure 4 The structure of the first detection circuit is schematically shown; Figure 1 and Figure 4 As shown, in some embodiments, when the photoelectric conversion circuit 120 includes a first detection circuit 120a, the first detection circuit 120a includes at least one first sub-detection circuit 122 respectively including first photosensitive elements PD, and each first sub-detection circuit 122 includes: a second operational amplifier U2, the first photosensitive element PD is connected between two input terminals of the second operational amplifier U2; a second output loop, including an optocoupler chip and a second transistor Q2, the light-emitting element LED2 of the optocoupler chip is connected in series with the second transistor Q2, the control end of the second transistor Q2 is connected to the output end of the second operational amplifier U2, and the photosensitive element PT2 of the optocoupler chip is connected to the output end OUT1 of the first sub-detection circuit 122.

[0077] The potential difference generated at both ends of the first photosensitive element PD is amplified by the second operational amplifier U2, and the electrical signal changes generated by the first photosensitive element PD being blocked by the tooth thickness profile of the sawtooth 220 when the sawtooth 220 passes through the first space 100a are accurately collected, and the optocoupler chip is driven to work, so that the second output circuit outputs the first electrical signal that accurately represents the distance between the tooth profiles of the sawtooth 220.

[0078] The first photosensitive element PD may include a plurality of first photosensitive elements PD arranged along the tooth height direction of the sawtooth 220 , and the first sub-detection circuit 122 where each first photosensitive element PD is located is used to detect the distance between tooth profiles at the corresponding tooth height position of the sawtooth 220 . In each first sub-detection circuit 122: when the light signal transmitted by the light source LED1 is not blocked by the sawtooth 220, the first photosensitive element PD is turned on, and a potential difference is generated at its two ends, so that the second operational amplifier U2 outputs a high level, and then the second transistor Q2 is turned on, and the current flows out from the power supply terminal Vcc through the light-emitting element LED2 of the optocoupler chip and flows into the ground line. The photosensitive element PT2 in the optocoupler chip senses that the light-emitting element LED2 emits light and works in the on state, and the output end OUT1 of the first sub-detection circuit 122 outputs a high level; when the light signal transmitted by the light source LED1 is blocked by the sawtooth 220, the first photosensitive element PD is turned off, and no potential difference is generated at its two ends, so that the second operational amplifier U2 outputs a low level, and the second transistor Q2 works in the off state, and the light-emitting element LED2 in the optocoupler chip does not work. At this time, the photosensitive element PT2 in the optocoupler chip is in the off state, and the output end OUT1 of the first sub-detection circuit 122 outputs a low level.

[0079] It should be noted that, in the specific circuit implementation, the "light source" and "light-emitting element" described in the above embodiments and to be described in the following embodiments, if not specifically stated, may be a light-emitting diode, or any electronic element that can emit light and can be used in a corresponding circuit module to implement the functions described in the present invention. Similarly, the "photosensitive element", if not specifically stated, may be a photosensitive diode, a phototransistor, and any electronic element that has a photosensitive effect and can be used in a corresponding circuit module to implement the functions described in the present invention. In addition, the "transistor" may be an NPN transistor, a PNP transistor, a crystal transistor, or other suitable transistor devices that can be used in a corresponding circuit module to implement the functions described in the present invention.

[0080] In some embodiments, each first sub-detection circuit 122 also includes any of the following electronic components: a second current limiting resistor R5, connected in series between the light-emitting element LED2 of the optocoupler chip and the second transistor Q2; a third current limiting resistor R6, connected in series with the photosensitive element PT2 of the optocoupler chip; a pull-up resistor R7, connected between the power supply terminal Vcc and the output terminal of the second operational amplifier U2.

[0081] The second current limiting resistor R5 and the third current limiting resistor R6 are used to provide current limiting protection in the corresponding loops. The pull-up resistor R7 is used to stabilize the output of the second operational amplifier U2 to avoid oscillation.

[0082] Furthermore, in some embodiments, when the photoelectric conversion circuit 120 includes the first detection circuit 120a, the first photosensitive element PD and the light source LED1 are arranged in a closed space, and the first space 100a is located in the closed space. In this way, the optical signal transmission between the light source LED1 and the first photosensitive element PD is ensured to be stable, thereby ensuring accurate detection of the distance between the tooth profiles of the sawtooth 220.

[0083] Figure 5 The structure of the second detection circuit is schematically shown; Figure 1 and Figure 5 As shown, in some embodiments, when the photoelectric conversion circuit 120 includes a second detection circuit 120b, the second detection circuit 120b includes a plurality of second sub-detection circuits 124 each including a second photosensitive element PT1, and each second sub-detection circuit 124 includes: a third operational amplifier U3, the second photosensitive element PT1 is connected between two input terminals of the third operational amplifier U3; a third output loop, including a fourth current limiting resistor R8 and a third transistor Q3 connected in series, the control terminal of the third transistor Q3 is connected to the output terminal of the third operational amplifier U3, and the series node of the fourth current limiting resistor R8 and the third transistor Q3 is connected to the output terminal OUT2 of the second sub-detection circuit 124.

[0084] The potential difference generated at both ends of the second photosensitive element PT1 is amplified by the third operational amplifier U3, and the electrical signal changes caused by the second photosensitive element PT1 being blocked by the end surface projection of the sawtooth when the sawtooth 220 passes through the second space 100b are accurately collected, and the third output circuit is driven to work, so that the third output circuit outputs a second electrical signal that accurately characterizes the end surface area of ​​the sawtooth 220.

[0085] Among them, the second photosensitive element PT1 includes a plurality of second photosensitive elements PT1 forming an array. According to the second photosensitive elements PT1 that are blocked in the second photosensitive element PT1 array when the sawtooth 220 passes through the second space 100b, the relevant parameters of the end surface area of ​​the sawtooth 220 can be obtained. Whether each second photosensitive element PT1 is blocked is judged according to the electrical signal it outputs. In each second sub-detection circuit 124: when the light signal emitted by the light source LED1 irradiates the sawtooth 220, the end surface of the sawtooth 220 is projected onto the second photosensitive element PT1 array, wherein the second photosensitive element PT1 that is not blocked by the end surface projection of the sawtooth 220 senses the light signal and generates a high-level signal, while the second photosensitive element PT1 that is blocked by the end surface projection of the sawtooth 220 generates a low-level signal; the high-level signal generated by the second photosensitive element PT1 is amplified by the third operational amplifier U3 to output a voltage signal to drive the third transistor Q3 to work in the amplification area. Assuming that the collector current of the third transistor Q3 is I C , then the voltage signal output by the output terminal OUT2 of the third output circuit is V OUT2 =Vcc-R8×IC On the contrary, if the second photosensitive element PT1 generates a low level signal, the third transistor Q3 works in the cut-off state, and the output terminal OUT2 of the third output circuit outputs a low voltage signal. The controller can determine whether the overall shape of the end surface of the sawtooth 220 changes by detecting the signal of the output terminal OUT2 of the third output circuit of each second sub-detection circuit 124.

[0086] Further, in some embodiments, when the photoelectric conversion circuit 120 includes the second detection circuit 120b: the second photosensitive element PT1 array and the light source LED1 are arranged in a closed space, and the second space 100b is located in the closed space. In this way, the optical signal transmission between the light source LED1 and the second photosensitive element PT1 is ensured to be stable, thereby ensuring accurate detection of the end surface area of ​​the sawtooth 220.

[0087] The embodiment of the present invention further provides a gear detection method, which is implemented based on the gear detection circuit described in any of the above embodiments. The features and principles of the gear detection circuit described in any of the above embodiments can be applied to the following gear detection method embodiments.

[0088] Figure 6 Illustrate the main steps of the gear inspection method; refer to Figure 6 , and combined with Figures 1 to 5 As shown, the gear detection method provided by the embodiment of the present invention includes: S610, setting a gear between the constant light-emitting circuit and the photoelectric conversion circuit, and controlling the gear to run so that each sawtooth of the gear passes through the illumination range of the constant light-emitting circuit in sequence; S620, obtaining the detection result of each sawtooth of the gear according to the electrical signal output by the photoelectric conversion circuit, including: S620a, in the case where the photoelectric conversion circuit includes a first detection circuit: obtaining first detection data representing the distance between the tooth profiles of each sawtooth according to the first electrical signal output by the first detection circuit, and obtaining a first detection result of whether the corresponding sawtooth is faulty according to the first detection data; S620b, in the case where the photoelectric conversion circuit includes a second detection circuit: obtaining second detection data representing the end face area of ​​each sawtooth according to the second electrical signal output by the second detection circuit, and obtaining a second detection result of whether the corresponding sawtooth is faulty according to the second detection data.

[0089] The parameters related to the distance between the tooth profiles and the end surface area of ​​the sawtooth can effectively reflect whether the sawtooth, especially the tooth surface of the sawtooth, has defects such as wear and displacement that affect the transmission performance. The gear detection circuit of the present invention detects the tooth thickness profile and end surface projection of the sawtooth through photoelectric sensing, and determines whether the sawtooth has defects such as wear and displacement. The health status of the gear can be accurately measured without disassembling the gear, providing a basis for ensuring the transmission performance of the gear.

[0090] In some embodiments, when the gear is a gear that performs rotational motion, obtaining first detection data characterizing the distance between tooth profiles of each sawtooth includes: calculating the distance L between tooth profiles at a tooth height position of a sawtooth. AB , , where the initial tooth profile distance at the tooth height position of the sawtooth and the center point of the gear form an isosceles triangle, L OB is the waist length of the isosceles triangle, w is the speed of the gear, t 1 It is the time that the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile at the tooth height position.

[0091] Figure 7 The end face shape of the sawtooth is shown in Figure 1. Figure 2 Taking the gear shown in the figure as an example, the end face shape of its sawtooth is shown as follows Figure 7 In the initial stage of the gear 200 being put into use, the tooth profile distances at each tooth height position of the sawtooth 220 and the center point O of the gear 200 form an isosceles triangle, and the tooth profile distances at each tooth height position are detected by the first photosensitive elements correspondingly arranged at each tooth height position. For example, the tooth profile distance L at the top tooth height position is AB It forms an isosceles triangle with the center point O of the gear 200, and the distance between the tooth profiles is L AB The first photosensitive element set at the top tooth height position is used for detection; the tooth profile distance L at the middle tooth height position CD It forms an isosceles triangle with the center point O of the gear 200, and the distance between the tooth profiles is L CD The first photosensitive element set at the middle tooth height position is used for detection; the tooth profile distance L at the bottom tooth height position EF It forms an isosceles triangle with the center point O of the gear 200, and the distance between the tooth profiles is L EF The detection is performed by the first photosensitive element arranged at the bottom tooth height position. OB , i.e., the distance between the top point B of the tooth profile and the center point O of the gear 200, is a known parameter of the gear 200; combined with the rotation speed w of the gear 200 and the time t that the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile at the tooth height position 1 , the distance L between the tooth profiles at the tooth height position of the sawtooth 220 is calculated using the Pythagorean theorem AB .

[0092] Distance between tooth profiles L CD and L EF The calculation process of is similar. , where L OD is the waist length of the isosceles triangle at the middle tooth height position, that is, the distance between the middle point D of the tooth profile and the center point O of the gear 200, which is a known parameter of the gear 200; t 2It is the time that the first photosensor at the middle tooth height position is blocked by the tooth thickness profile at the tooth height position. , where L OF is the waist length of the isosceles triangle at the bottom tooth height position, that is, the distance between the bottom point F of the tooth profile and the center point O of the gear 200, which is a known parameter of the gear 200; t 3 It is the time that the first photosensor at the bottom tooth height position is blocked by the tooth thickness profile at the tooth height position.

[0093] When the gear is a gear that performs linear motion, the distance between the tooth profiles of the sawtooth at the tooth height position can be directly obtained based on the running speed of the gear and the time when the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile of the sawtooth at the tooth height position.

[0094] In some embodiments, a first detection result of whether the corresponding sawtooth is faulty is obtained based on the first detection data, including: comparing the first detection data of each sawtooth with the first abnormal reference range and / or the first fault reference range; when the first detection data of a sawtooth falls into the first abnormal reference range, determining that the sawtooth is abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, determining that the sawtooth is faulty; when the first detection data of a sawtooth falls into the first fault reference range, determining that the sawtooth is faulty.

[0095] When the first detection data of a sawtooth falls into the first abnormal reference range, it indicates that the distance between the tooth profiles of the sawtooth is abnormal (for example, a gap appears on the tooth surface of the sawtooth or the gear is displaced), and the sawtooth may be faulty; to avoid errors caused by a single test, when a sawtooth is determined to be abnormal for multiple consecutive times (for example, it is determined to be abnormal 10 to 40 times in a row), the sawtooth is determined to be faulty. When the first detection data of a sawtooth falls into the first fault reference range, it indicates that the distance between the tooth profiles of the sawtooth has seriously deviated from the initial value (for example, the sawtooth is seriously damaged or even falls off), so the sawtooth is determined to be faulty.

[0096] In some embodiments, second detection data characterizing the end face area of ​​each sawtooth is obtained, including: when the corresponding sawtooth passes through the second space, determining the blocked second photosensitive element according to the electrical signal output by each second photosensitive element in the second photosensitive element array; determining the end face area of ​​the sawtooth according to the blocked second photosensitive element.

[0097] The light source, the sawtooth to be detected and the second photosensitive element array can be arranged along the tooth width direction of the sawtooth to be detected, and the second photosensitive element array can be consistent with the initial size of the sawtooth in the tooth thickness direction, so as to facilitate the detection of the end surface area of ​​the sawtooth. When a sawtooth passes through the second space, the end surface of the sawtooth is projected onto the second photosensitive element array by the light signal, and the end surface area of ​​the sawtooth can be determined based on the area of ​​the second photosensitive element blocked by the projection of the end surface of the sawtooth.

[0098] In some embodiments, a second detection result of whether the corresponding sawtooth is faulty is obtained based on the second detection data, including: comparing the second detection data of each sawtooth with a second abnormal reference range and / or a second fault reference range; when the second detection data of a sawtooth falls into the second abnormal reference range, determining that the sawtooth is abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, determining that the sawtooth is faulty; when the second detection data of a sawtooth falls into the second fault reference range, determining that the sawtooth is faulty.

[0099] When the second detection data of a sawtooth falls into the second abnormal reference range, it indicates that the end surface area of ​​the sawtooth is abnormal (for example, a notch appears on the tooth surface of the sawtooth or the gear is displaced), and the sawtooth may be faulty; to avoid errors caused by a single test, when a sawtooth is determined to be abnormal for multiple consecutive times (for example, it is determined to be abnormal 10 to 40 times in a row), the sawtooth is determined to be faulty. When the second detection data of a sawtooth falls into the second fault reference range, it indicates that the end surface area of ​​the sawtooth has seriously deviated from the initial value (for example, the sawtooth has fallen off or is seriously damaged, etc.), so the sawtooth is determined to be faulty.

[0100] In some embodiments, when the photoelectric conversion circuit includes a first detection circuit, if the first detection result indicates more than two sawtooth faults; and / or, when the photoelectric conversion circuit includes a second detection circuit, if the second detection result indicates more than two sawtooth faults; and / or, when the photoelectric conversion circuit includes a first detection circuit and a second detection circuit, if the first detection result and the second detection result indicate the same sawtooth fault; then, a gear fault is determined.

[0101] Failure of more than two saw teeth or serious abnormalities of multiple parameters of the same saw tooth will seriously affect the transmission performance of the gear, so gear failure is determined.

[0102] The present invention also provides a gear monitoring method for an electric power steering system, which is implemented based on the gear detection method described in any of the above embodiments. The features and principles of the gear detection method described in any of the above embodiments can be applied to the following gear monitoring method embodiments for an electric power steering system.

[0103] Figure 8 The main steps of the gear monitoring method of the electric power steering system are shown; Figure 8 , and combined with Figures 1 to 7 As shown, the gear monitoring method of the electric power steering system provided by the embodiment of the present invention includes: S810, when the detection result indicates at least one sawtooth fault, issuing an alarm including the detection result; S820: When the vehicle is ignited next time, if the alarm is not eliminated, the electric power steering system is controlled to refuse to provide power assistance.

[0104] The detection result includes a first detection result of the first detection circuit detecting whether the sawtooth is faulty based on the distance between the tooth profiles of the sawtooth, and / or a second detection result of the second detection circuit detecting whether the sawtooth is faulty based on the end surface area of ​​the sawtooth. The gears of the electric power steering system are detected based on the above-mentioned gear detection method, and the tooth profile and end surface of the sawtooth are detected during the operation of the gear by photoelectric sensing to monitor whether the sawtooth has defects such as wear and displacement, and when a sawtooth fault is detected, the driver is promptly reminded to take countermeasures, thereby improving the reliability and safety of the electric power steering system.

[0105] The gear monitoring method of the electric power steering system can be specifically executed by the controller of the electric power steering system or the controller of the whole vehicle. During the operation of the electric power steering system, the gear detection circuit works continuously, and the controller can calculate the distance between the tooth profiles / end surface area of ​​each sawtooth of the gear according to the set frequency (for example, 10 to 10,000 times / second, preferably 100 to 1,000 times / second), and judge whether the corresponding sawtooth is abnormal / faulty and whether the gear is faulty; when it is judged that there are more than two sawtooth faults, multiple parameters of the same sawtooth are seriously abnormal, etc., the controller will issue an alarm to remind the driver to check the gear condition of the electric power steering system; when the vehicle is ignited next time, if the controller checks that the gear condition has improved, the electric power steering system provides power assistance normally; if the alarm is not eliminated or the controller checks that the gear condition has not improved, the electric power steering system is controlled to refuse to provide power assistance.

[0106] An embodiment of the present invention also provides an electronic device that stores a program, which, when executed by a processor, implements the gear detection method described in any of the above embodiments, and / or implements the gear monitoring method of the electric power steering system described in any of the above embodiments.

[0107] When the gear detection solution is applied to an electric power steering system, the electronic device can be connected to the controller of the electric power steering system or the controller of the whole vehicle to monitor the health of the gears of the electric power steering system.

[0108] In specific implementation, the electronic device may be in the following three forms.

[0109] It is formed in the form of a functional (program) module architecture, and may include modules for respectively implementing the various steps of the above-mentioned gear detection method / gear monitoring method of the electric power steering system, for example, including functional modules for implementing steps S610, S620, S810, and S820.

[0110] It is in the form of a computer program product, which includes a computer program. When the computer program is executed by a processor, the gear detection method / gear monitoring method of an electric power steering system described in any of the above embodiments is implemented.

[0111] It is expressed in the form of a storage medium, in which a program is stored, and when the program is executed by a processor, the gear detection method / gear monitoring method of the electric power steering system described in any of the above embodiments is implemented. The storage medium can be any tangible medium that contains or stores the program, and can specifically adopt any combination of one or more readable media, and the readable medium can be a readable signal medium or a readable storage medium. The program can be used by an instruction execution system, an apparatus or a device or used in combination with it. The program can be executed entirely on the user computing device, partially on the user device, as an independent software package, partially on the user computing device and partially on the remote computing device, or completely on the remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network LAN or a wide area network WAN, or can be connected to an external computing device, for example, using an Internet service provider to connect through the Internet.

[0112] In some embodiments, the electronic device further comprises a processor for executing the program.

[0113] When the gear detection solution is applied to the electric power steering system, the electronic device can be the controller of the electric power steering system or the controller of the whole vehicle. It can detect the tooth profile and end face of the sawtooth during the operation of the gear through photoelectric sensing, monitor whether the sawtooth has defects such as wear and displacement, and promptly remind the driver to take countermeasures when a sawtooth fault is detected, thereby improving the reliability and safety of the electric power steering system.

[0114] Fig. 9 The structure of the electronic device in this embodiment is shown schematically; Fig. 9 As shown, the electronic device 900 can be formed in the form of a general-purpose computing device, which includes a processing unit 910 and a storage unit 920. The storage unit 920 stores executable instructions. When the executable instructions are executed by the processing unit 910, the gear detection method / gear monitoring method of the electric power steering system described in any of the above embodiments is implemented. Among them, the storage unit 920 may include a program / utility with one or more program modules, and the program module includes but is not limited to: an operating system, one or more application programs, other program modules, and program data. The general-purpose computing device also includes a bus 930 connecting the processing unit 910 and the storage unit 920, as well as other platform components. The bus 930 may include a storage unit bus, a peripheral bus, a graphics acceleration port, a processing unit bus, and other local buses. The general-purpose computing device can also communicate with one or more external devices, other computing devices of the vehicle, a network (such as a local area network LAN, a wide area network WAN and / or a public network, such as the Internet), etc.

[0115] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A gear detection circuit, characterized in that: include: A constant light emitting circuit, comprising a light source for emitting a light signal with a constant light intensity; Photoelectric conversion circuit, comprising: A first detection circuit, comprising at least one first photosensitive element, wherein the first photosensitive element is located within the illumination range of the light source, and a first space for the sawtooth of the gear to pass through is formed between the first photosensitive element and the light source, and the first detection circuit is used to output a first electrical signal generated by the first photosensitive element sensing the light signal and being blocked by the tooth thickness profile of the sawtooth; Wherein, the first photosensitive elements include a plurality of first photosensitive elements, and the plurality of first photosensitive elements are arranged along the tooth height direction of the sawtooth; when the corresponding sawtooth passes through the first space, the tooth thickness contours at each tooth height position of the sawtooth respectively block the light signals irradiated by the light source to the plurality of first photosensitive elements, and the first detection circuit outputs a first electrical signal representing the distance between the tooth profiles at each tooth height position of the sawtooth; and / or A second detection circuit, comprising a second photosensitive element array, the second photosensitive element array being located within the illumination range of the light source, a second space for the sawtooth to pass through being formed between the second photosensitive element array and the light source, the second detection circuit being used to output a second electrical signal generated by the second photosensitive element array sensing the light signal and being blocked by the end surface projection of the sawtooth; When the corresponding sawtooth passes through the second space, the light source illuminates the end face of the sawtooth and projects it onto the second photosensitive element array, and the second detection circuit outputs a second electrical signal representing the end face area of ​​the sawtooth.

2. The gear detection circuit according to claim 1, characterized in that: The light source is a parallel light source; In the case where the photoelectric conversion circuit includes the first detection circuit: The parallel light source irradiates the first photosensitive element vertically; when the corresponding sawtooth passes through the first space, the parallel light source, the sawtooth and the first photosensitive element are arranged along the tooth width direction of the sawtooth; In the case where the photoelectric conversion circuit includes the second detection circuit: The parallel light source vertically illuminates the second photosensitive element array; when the corresponding sawtooth passes through the second space, the parallel light source, the sawtooth and the second photosensitive element array are arranged along the tooth width direction of the sawtooth.

3. The gear detection circuit according to claim 1, characterized in that: The constant light emitting circuit comprises a negative feedback circuit, and the light source is connected to an output end of the negative feedback circuit.

4. The gear detection circuit according to claim 3, characterized in that: The negative feedback circuit comprises: A first operational amplifier, wherein a constant voltage is input to a non-inverting input terminal of the first operational amplifier; A first triode, wherein a control end of the first triode is connected to an output end of the first operational amplifier; The first output loop includes the light source, the first transistor and a sampling resistor connected in series, and the series node of the sampling resistor and the first transistor is connected to the inverting input terminal of the first operational amplifier.

5. The gear detection circuit according to claim 4, characterized in that: The constant light emitting circuit further includes a shaping circuit connected between a pulse signal input terminal and a non-inverting input terminal of the first operational amplifier, the shaping circuit including: A first resistor and a second resistor connected in parallel, wherein the first ends of the first resistor and the second resistor are respectively connected to the pulse signal input end, and the second end of the first resistor is grounded; A first capacitor and a second capacitor are connected in parallel, wherein the first ends of the first capacitor and the second capacitor are respectively connected to the second end of the second resistor and the non-inverting input end of the first operational amplifier, and the second ends of the first capacitor and the second capacitor are respectively grounded.

6. The gear detection circuit according to claim 1, characterized in that: In the case where the photoelectric conversion circuit includes the first detection circuit, the first detection circuit includes at least one first sub-detection circuit including first photosensitive elements, each of which includes: a second operational amplifier, wherein the first photosensitive element is connected between two input terminals of the second operational amplifier; The second output circuit includes an optocoupler chip and a second transistor, the light-emitting element of the optocoupler chip is connected in series with the second transistor, the control end of the second transistor is connected to the output end of the second operational amplifier, and the photosensitive element of the optocoupler chip is connected to the output end of the first sub-detection circuit.

7. The gear detection circuit according to claim 6, characterized in that: Each of the first sub-detection circuits further includes any of the following electronic components: A second current limiting resistor is connected in series between the light emitting element of the optocoupler chip and the second transistor; A third current limiting resistor is connected in series with the photosensitive element of the optocoupler chip; The pull-up resistor is connected between the power supply terminal and the output terminal of the second operational amplifier.

8. The gear detection circuit according to claim 1, characterized in that: In the case where the photoelectric conversion circuit includes the second detection circuit, the second detection circuit includes a plurality of second sub-detection circuits respectively including second photosensitive elements, and each of the second sub-detection circuits includes: a third operational amplifier, wherein the second photosensitive element is connected between two input terminals of the third operational amplifier; The third output loop includes a fourth current limiting resistor and a third triode connected in series, the control end of the third triode is connected to the output end of the third operational amplifier, and the series node of the fourth current limiting resistor and the third triode is connected to the output end of the second sub-detection circuit.

9. A gear detection method, characterized in that: The gear detection circuit according to any one of claims 1 to 8 is implemented, comprising: The gear is arranged between the constant light-emitting circuit and the photoelectric conversion circuit, and the gear is controlled to run so that each sawtooth of the gear passes through the illumination range of the constant light-emitting circuit in sequence; Obtaining the detection result of each of the saw teeth of the gear according to the electrical signal output by the photoelectric conversion circuit, including: In the case where the photoelectric conversion circuit includes a first detection circuit: obtaining first detection data representing the distance between tooth profiles of each sawtooth according to a first electrical signal output by the first detection circuit, and obtaining a first detection result of whether the corresponding sawtooth is faulty according to the first detection data; In the case where the photoelectric conversion circuit includes a second detection circuit: second detection data characterizing the end surface area of ​​each sawtooth is obtained based on a second electrical signal output by the second detection circuit, and a second detection result of whether the corresponding sawtooth is faulty is obtained based on the second detection data.

10. The gear detection method according to claim 9, characterized in that: When the gear is a gear that performs rotational motion, the step of obtaining first detection data characterizing the distance between tooth profiles of each sawtooth includes: Calculate the distance L between the tooth profiles at the tooth height position of a sawtooth AB , , wherein the initial tooth profile distance at the tooth height position of the sawtooth and the center point of the gear form an isosceles triangle, L OB is the waist length of the isosceles triangle, w is the rotation speed of the gear, and t1 is the time when the first photosensitive element at the corresponding tooth height position is blocked by the tooth thickness profile at the tooth height position.

11. The gear detection method according to claim 9, characterized in that: The obtaining, according to the first detection data, a first detection result of whether the corresponding sawtooth is faulty includes: Comparing the first detection data of each sawtooth with a first abnormal reference range and / or a first fault reference range; When the first detection data of a sawtooth falls into the first abnormal reference range, the sawtooth is determined to be abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, the sawtooth is determined to be faulty; When the first detection data of a sawtooth falls within the first fault reference range, the sawtooth fault is determined.

12. The gear detection method according to claim 9, characterized in that: The obtaining of second detection data characterizing the end surface area of ​​each sawtooth comprises: When the corresponding sawtooth passes through the second space, the blocked second photosensitive element is determined according to the electrical signal output by each second photosensitive element in the second photosensitive element array; The end surface area of ​​the sawtooth is determined according to the blocked second photosensitive element.

13. The gear detection method according to claim 9, characterized in that: The obtaining, according to the second detection data, a second detection result of whether the corresponding sawtooth is faulty includes: comparing the second detection data of each sawtooth with a second abnormal reference range and / or a second fault reference range; When the second detection data of a sawtooth falls into the second abnormal reference range, the sawtooth is determined to be abnormal; when a sawtooth is determined to be abnormal for multiple consecutive times, the sawtooth is determined to be faulty; When the second detection data of a sawtooth falls into the second fault reference range, the sawtooth fault is determined.

14. The gear detection method according to claim 9, characterized in that: In the case where the photoelectric conversion circuit includes the first detection circuit, if the first detection result indicates more than two sawtooth faults; and / or, in the case where the photoelectric conversion circuit includes the second detection circuit, if the second detection result indicates more than two sawtooth faults; and / or, in the case where the photoelectric conversion circuit includes the first detection circuit and the second detection circuit, if the first detection result and the second detection result indicate the same sawtooth fault; Then, it is determined that the gear is faulty.

15. A gear monitoring method for an electric power steering system, characterized in that: The gear detection method according to any one of claims 9 to 14 is implemented, comprising: When the detection result indicates at least one sawtooth fault, issuing an alarm including the detection result; When the vehicle is ignited next time, if the alarm is not eliminated, the electric power steering system is controlled to refuse to provide power assistance.

16. An electronic device, characterized in that: The electronic device stores a program, and when the program is executed by a processor, the method according to any one of claims 9 to 15 is implemented.

17. The electronic device according to claim 16, characterized in that: The electronic device also includes a processor for executing the program.

Images