Gear rotating speed signal acquisition mode and coaxial speed measurement method

Abstract

The invention discloses a gear rotating speed signal acquisition mode and a coaxial speed measurement method, and relates to the technical field of pipeline reinforcement, and the gear rotating speed signal acquisition mode comprises a signal acquisition module which acquires rotating operation of a gear and converts tooth peaks and tooth valleys into square wave signals; the signal conditioning module is used for processing the square wave signal and outputting a pulse signal; and the processing module is used for processing and comparing the collected pulse signals. The beneficial effect of the invention is that the magnetic field / light can be blocked or changed when passing through the sensor. When the gear rotates, passing of each tooth can generate a signal change on the sensor, so that a square wave signal is generated. And the speed of the gear is calculated according to a frequency formula.

Description

Technical Field

[0001] The invention relates to the technical field of installation and fixing, in particular to a gear speed signal acquisition method and a coaxial speed measurement method. Background Art

[0002] To replace the generator speed gear, the fan casing and impeller at the tail of the generator need to be disassembled, the generator and the engine need to be disassembled, and the generator needs to be lifted off the frame by a crane. The generator is sent to the factory to be disassembled and the speed gear is replaced. After the replacement is completed, the generator is dynamically balanced again, and after passing the test, it is hoisted to the frame and coupled to the engine. Such a working cycle takes about a week. Compared with replacing the main generator, this renovation work saves a lot of time and not only improves the maintenance efficiency. It also avoids high-risk operations such as high-altitude operations and hoisting operations, reduces safety risks at work, and provides strong guarantees for production. Summary of the invention

[0003] Some simplifications or omissions may be made in this section and the abstract and title of the present application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0004] In view of the above-mentioned prior art problems, the present invention is proposed.

[0005] The present invention aims to provide a gear speed signal acquisition method, which aims to solve the problem of how to realize signal acquisition.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a gear speed signal acquisition method, which includes a signal acquisition module, which acquires the rotation of the gear and converts the tooth peaks and tooth valleys into square wave signals;

[0007] The signal conditioning module processes the square wave signal and outputs a pulse signal;

[0008] The processing module processes and compares the collected pulse signals.

[0009] As a preferred solution of the gear speed signal acquisition method of the present invention, the signal acquisition module includes a Hall effect sensor, and the tooth peaks and tooth valleys change the magnetic field strength and direction passing through the sensor, thereby forming a square wave signal.

[0010] As a preferred solution of the gear speed signal acquisition method of the present invention, the signal conditioning module includes a signal processing circuit, which converts the weak magnetic field change signal detected by the Hall sensor into a voltage signal.

[0011] As a preferred solution of the gear speed signal acquisition method of the present invention, the signal processing circuit converts the differential voltage signal into a digital signal, and the signal processing circuit also includes unit modules such as filtering, amplification and adaptive comparison.

[0012] As a preferred solution of the gear speed signal acquisition method of the present invention, the processing module includes a frequency detection circuit for analyzing the frequency of the square wave signal;

[0013] Single chip microcomputer with built-in frequency conversion software that can process the frequency modulation of pulse signals;

[0014] Output circuit, outputs pulse signal.

[0015] The beneficial effect of the gear speed signal acquisition method of the present invention is that the magnetic field / light will be blocked or changed when passing through the sensor. When the gear rotates, each tooth passing will produce a signal change on the sensor, thereby generating a square wave signal. The speed of the gear is calculated based on the frequency formula.

[0016] Another object of the present invention is to provide a coaxial speed measurement method, which aims to solve the problem of how to achieve signal acquisition without disassembling the device.

[0017] In order to solve the above technical problems, the present invention also provides the following technical solutions: a coaxial speed measurement method, which includes a gear speed signal acquisition method; and the pulse signal of the engine speed sensor is input to the electronic control system after pulse signal frequency modulation processing, and the electronic control system issues a speed command and detects the actual speed at the same time.

[0018] As a preferred solution of the coaxial speed measurement method of the present invention, the ratio of the number of engine teeth to the number of generator teeth is the frequency modulation ratio.

[0019] As a preferred solution of the coaxial speed measurement method of the present invention, wherein:

[0020]

[0021] f is the frequency of the pulse;

[0022] n is the rotation speed;

[0023] P is the number of pulses generated per revolution.

[0024] As a preferred solution of the coaxial speed measurement method of the present invention, wherein: n=A*f.

[0025] As a preferred solution of the coaxial speed measurement method of the present invention, the error between the speed command and the actual speed is less than 100RPM.

[0026] The beneficial effect of the coaxial speed measurement method of the present invention is: by utilizing the principle of co-rotation speed, gears with different numbers of teeth are converted into pulse signals through a collector, and then through the relationship between the gear ratio and the frequency, it is still possible to detect whether the entire device can operate without disassembling the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0028] Figure 1 This is a signal transmission flow chart of the present invention.

[0029] Figure 2 This is a simplified diagram of the coaxial gear speed measurement in the present invention. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0033] Example 1

[0034] The first embodiment of the present invention provides a gear speed signal acquisition method, in which a photoelectric sensor or Hall effect sensor is installed near the gear. These sensors can detect the tooth peaks and tooth valleys of the gear because they block or change the magnetic field / light when passing through the sensor. When the gear rotates, each tooth passing will produce a signal change on the sensor, thereby generating a square wave signal. This square wave signal represents the tooth peaks and tooth valleys of the gear, and its frequency is proportional to the speed of the gear. The square wave signal is then sent to the signal conditioning module, which may include a filter to remove noise, and a shaping circuit such as a Schmitt trigger to ensure the stability and accuracy of the signal, and finally output a clean pulse signal. The counter in the processing module counts the conditioned pulse signal. Within a certain time interval, the number of pulses recorded by the counter directly corresponds to the number of teeth rotated by the gear. By measuring the number of pulses within a certain period of time, we can calculate the speed of the gear. If we know the number of teeth of the gear, we can even calculate the linear speed of the gear. The collected data will be further analyzed by the software and compared with the preset normal working parameters to detect any deviation or abnormality.

[0035] Example 2

[0036] A second embodiment of the present invention, including Hall Effect sensors such as the CYGTS211 / 212 and CYGTS288, is designed for non-contact measurement of the speed of rotating gears. These sensors can be mounted near the gears so that they can detect the peaks and valleys of the gear teeth. The sensors are typically waterproof, dustproof, and oil-proof, allowing them to operate reliably in harsh environments.

[0037] These sensors use a magnetically biased Hall-effect integrated circuit to accurately detect the rotational motion of ferrous metal gears. The magnetically biased integrated circuit inside the sensor is sealed in a metal package, providing physical protection and reducing installation costs. The Hall-effect sensor can distinguish between the peaks and valleys of the rotating gear and convert these changes into a square wave output signal. For each pair of peaks and valleys, the sensor outputs a square wave signal with one cycle, that is, the conversion ratio is K=1.

[0038] When the gear rotates, the peaks and valleys of each tooth pass through the sensor, causing the magnetic field strength detected by the sensor to change. This change is converted into a square wave signal by the sensor, where the peaks and valleys correspond to the high and low levels of the square wave signal respectively.

[0039] The square wave signal output by the sensor may require further conditioning to ensure the stability and reliability of the signal. This may include steps such as filtering, amplification, and shaping. For example, the LD1921 is a gear sensor circuit based on the Hall effect, which contains unit modules such as a voltage regulator, input stage overvoltage protection, output stage overvoltage protection, a differential Hall sensor, temperature compensation, a small signal amplifier, a high-pass filter, an adaptive window comparator, and an open collector output stage. These components work together to convert the weak magnetic field changes into voltage signals and trigger the output stage circuit to generate high and low level digital signals corresponding to the shape of the gear.

[0040] The conditioned signal, that is, the square wave signal, can be connected to TTL, CMOS circuits and universal tachometers to form a speed measurement and control system. The output of these signals is a digital current sink OC or RC, and has reverse polarity protection and output short circuit protection to ensure that the sensor will not be damaged even if the power supply is reversed.

[0041] Use Schmitt trigger also known as hysteresis comparator to shape square wave signal. Schmitt trigger is able to convert the input square wave signal into clean pulse signal with well-defined rising and falling edges.

[0042] The high level of the input square wave signal triggers the positive threshold of the Schmitt trigger and outputs a high level; the low level triggers the negative threshold and outputs a low level.

[0043] A low-pass filter is added at the output of the Schmitt trigger to remove possible high-frequency noise and spikes to ensure that the output pulse signal is stable and jitter-free.

[0044] If the output pulse signal amplitude is not enough to drive the subsequent circuit, an operational amplifier can be used to amplify the signal to ensure the signal strength and driving capability.

[0045] If necessary, the width of the output pulse can be changed by adjusting the hysteresis voltage of the Schmitt trigger to adapt to different counters or logic circuits.

[0046] Add a buffer at the output of the Schmitt trigger to increase the driving capability and reduce the impact of the load on the signal.

[0047] The shaped pulse signal is sent to a pulse counter, such as a 555 timer configured in monostable mode or multivibrator mode, to generate a single pulse or a periodic pulse.

[0048] As needed, the pulse signal can be sent to logic gate circuits, such as AND gates, OR gates, NOT gates, etc., to achieve more complex logical functions.

[0049] Finally, the processed pulse signal is connected to a microcontroller, PLC or other digital device through an appropriate interface to achieve speed monitoring, counting or other control functions.

[0050] Example 3

[0051] Reference Figures 1-2 , which is the third embodiment of the present invention, and this embodiment further provides a coaxial speed measurement method.

[0052] Since the main generator and the engine rotate on the same axis, their speeds are the same, so only the speed of one of them needs to be measured.

[0053] The speed of a gear can be detected contactlessly using a Hall Effect sensor, which converts the peaks and valleys of the gear teeth into square wave signals whose frequency is proportional to the speed of the gear.

[0054] The square wave signals generated by the Hall Effect Sensor can be processed by the signal conditioning module to output pulse signals. Schmitt triggers can be used to shape these square wave signals to ensure that they have clear rising and falling edges, suitable for counting and further processing.

[0055] According to the pulse frequency calculation formula, the gear speed can be obtained by calculating the number of pulses per unit time.

[0056] According to ngen = A*f. In this case, the number of pole pairs is known because the gear ratio of the main generator and the engine is known.

[0057] By measuring the pulse signal frequency of the engine gear, the engine speed can be calculated. Then, according to the gear ratio of the main generator and the engine, the speed of the main generator can be calculated.

[0058] The electronic control system will issue a speed command ENGCMD and detect the actual speed ENGSPD at the same time. If the actual speed deviates from the speed command by more than 100RPM, the control system will report a fault and cannot be loaded.

[0059] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

[0060] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0061] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0062] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A gear speed signal acquisition method, characterized by: include, The signal acquisition module collects the rotation of the gear and converts the tooth peaks and tooth valleys into square wave signals; The signal conditioning module processes the square wave signal and outputs a pulse signal; The processing module processes and compares the collected pulse signals.

2. The gear speed signal acquisition method according to claim 1, characterized in that: The signal acquisition module contains a Hall effect sensor. The peaks and valleys of the teeth change the strength and direction of the magnetic field passing through the sensor, thus forming a square wave signal.

3. The gear speed signal acquisition method according to claim 2, characterized in that: The signal conditioning module includes a signal processing circuit that converts the weak magnetic field change signal detected by the Hall sensor into a voltage signal.

4. The gear speed signal acquisition method according to claim 3, characterized in that: The signal processing circuit converts the differential voltage signal into a digital signal, and the signal processing circuit also includes filtering, amplification, adaptive comparison and other unit modules.

5. The gear speed signal acquisition method according to claim 4, characterized in that: The processing module includes a frequency detection circuit for analyzing the frequency of the square wave signal; Single chip microcomputer with built-in frequency conversion software that can process the frequency modulation of pulse signals; Output circuit, outputs pulse signal.

6. A coaxial speed measurement method, characterized in that: Including gear speed signal acquisition method; Furthermore, the pulse signal of the engine speed sensor is input to the electronic control system after the pulse signal frequency modulation processing, and the electronic control system issues a speed command and detects the actual speed at the same time.

7. The coaxial speed measurement method according to claim 6, characterized in that: The ratio of the number of engine teeth to the number of generator teeth is the frequency modulation ratio (A).

8. The coaxial speed measurement method according to claim 7, characterized in that: f is the frequency of the pulse (unit: Hz, i.e. the number of pulses per second); n is the speed (unit: RPM, i.e. revolutions per minute); P is the number of pulses generated per revolution.

9. The coaxial speed measurement method according to claim 8, characterized in that: n(generator)=A*f.

10. The coaxial speed measurement method according to claim 9, characterized in that: The error between the speed command and the actual speed is less than 100RPM.

Images