Eyepiece disc positioning control device independent of encoder

Abstract

An eyepiece disc positioning control device independent of an encoder comprises an eyepiece disc, a photoelectric switch sensor module and a main control board, a plurality of eyepiece positioning holes are formed in the eyepiece disc around a circumferential array at equal intervals, the eyepiece disc is provided with an eyepiece disc reset hole, and the eyepiece disc reset hole is formed in the circumferential array track of the eyepiece positioning holes. A photoelectric switch sensor is arranged in the photoelectric switch sensor module, the arrangement position of the photoelectric switch sensor is matched with the arrangement track of the eyepiece positioning hole and the eyepiece disc reset hole, and the photoelectric switch sensor module is in circuit connection with the main control board. The beneficial effects of the utility model are that step loss accumulation of the stepping motor is effectively avoided, and positioning is accurate. According to the scheme, infrared rays are used as signals, and the equipment shell is used for shading, so that environmental interference is small. According to the scheme, the photoelectric switch sensor is adopted, and the photoelectric switch sensor has the characteristics of low cost and small occupied space, so that the cost of the scheme is reduced, the size is smaller, and the photoelectric switch sensor is suitable for popularization and application.

Description

Technical Field

[0001] The utility model relates to the field of motor control, and more specifically to an eyepiece disc positioning control device which does not rely on an encoder. Background Art

[0002] When the existing eyepiece disk device is in use, when the eyepiece disk needs to be rotated to replace the eyepiece, a simple open-loop automatic control method is adopted. The main control board receives user instructions and sends signals to the drive modules of the left and right stepper motors. The left and right stepper motors receive the pulse signals from the motor drive modules and start to rotate a certain number of steps, driving the eyepiece disk to rotate to the target position through gears.

[0003] Since the stepper motor generates magnetism according to a certain rule through the internal fixed coil, it alternately attracts the permanent magnet on the rotor to make the rotor rotate. Due to the limited magnetic force, the moment of inertia of the load carried by the rotor cannot be too large. When the environmental resistance is too large at certain moments, the rotor may not be able to rotate effectively with a small probability, which will cause step loss. At this time, the main control board can only send control instructions according to demand, and it is unknown whether the stepper motor is executed and whether it is executed accurately. A few steps may be within the error, but with the repeated use of the equipment or device, the accumulation of step loss of the stepper motor cannot be avoided, causing the eyepiece disc to move farther and farther away from the target position when the stepper motor stops. Therefore, if you want to accurately control the rotation of the eyepiece disc to achieve the purpose of replacing the eyepiece, it is necessary to monitor the position of the eyepiece disc.

[0004] In the prior art, sensors are required to obtain the position of the eyepiece disk. Currently, there are many sensors used in the monitoring of the eyepiece disk position, such as capacitive sensors, magnetic induction encoders, etc., all of which require the use of encoders. Among them, signal generation modules and communication protocols need to occupy more main control board resources, and the requirements for the main control board are high; and the modules are more complex, which will also increase costs, and the problems generated are also more complicated; due to the greater electromagnetic influence, there is an electromagnetic field inside the stepper motor, and other external magnetic fields will also interfere with the judgment of the position. Therefore, in order to simplify the structure, there is an urgent need for an eyepiece disk positioning control device that does not rely on an encoder. Utility Model Content

[0005] The utility model overcomes the shortcomings of the prior art and provides an eyepiece disc positioning control device which does not rely on an encoder.

[0006] The purpose of the utility model is achieved through the following technical solutions.

[0007] An eyepiece disk positioning control device that does not rely on an encoder comprises an eyepiece disk, a photoelectric switch sensor module and a main control board, wherein a plurality of eyepiece positioning holes are equidistantly arranged on the eyepiece disk around a circular array, the eyepiece disk is provided with an eyepiece disk reset hole, the eyepiece disk reset hole is arranged on the circular array track of the eyepiece positioning holes, a photoelectric switch sensor is arranged in the photoelectric switch sensor module, the setting position of the photoelectric switch sensor matches the setting track of the eyepiece positioning hole and the eyepiece disk reset hole, and the photoelectric switch sensor module is connected to the main control board circuit.

[0008] The optical sensor comprises an infrared emitting diode and a phototransistor, the infrared emitting diode and the phototransistor are arranged side by side in the housing of the photoelectric switch sensor module, and the bases of the infrared emitting diode and the phototransistor are arranged correspondingly.

[0009] The emitter of the phototransistor is connected to a low level, the collector of the phototransistor is connected to the infrared emitting diode circuit as an output pole, and any one of the two pins of the infrared emitting diode is connected to the power supply voltage after being connected in series with a small resistance.

[0010] The output terminal of the photoelectric switch sensor emitter is connected to a Schmitt trigger.

[0011] The pins of the main control board's interface for receiving high and low level signals from the photoelectric switch sensor module and the signal input pins of the photoelectric switch sensor module's power supply interface are connected to the low level through a low-capacitance bidirectional diode.

[0012] The number of the eyepiece positioning holes is the same as the number of the eyepiece mounting holes arranged on the eyepiece plate, and the eyepiece positioning holes correspond to the eyepiece mounting holes in one-to-one arrangement position.

[0013] The ratio of the setting track distance between the eyepiece disk reset hole and the two adjacent eyepiece positioning holes is 1:2.

[0014] There are two eyepiece discs, and the installation positions of the two eyepiece discs are relatively arranged on the left and right.

[0015] The number of eyepiece mounting holes is 8.

[0016] The beneficial effects of the utility model are:

[0017] 1. Effectively avoid the accumulation of lost steps of the stepper motor and achieve accurate positioning. This solution uses infrared as a signal and uses the device shell for light shielding, so that it is less affected by environmental interference.

[0018] 2. This solution uses a photoelectric switch sensor. Since the photoelectric switch sensor has the characteristics of low cost and small space occupation, it not only reduces the cost of the solution but also has a smaller volume, which is suitable for popularization and use. On this basis, since the photoelectric switch sensor will not directly contact the eyepiece plate, it can effectively avoid wear and tear, thereby increasing the service life of the device.

[0019] 3. Since the photoelectric switch sensor module has the characteristics of simple structure and signal transmission method, it has low requirements for the main control board. The single-sided eyepiece disk only occupies one pin of the main control board, which effectively saves the main control board resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the front structure diagram of the eyepiece disc;

[0021] Figure 2 This is the back view of the eyepiece disc positioning structure;

[0022] Figure 3 This is the front view of the eyepiece disc positioning structure;

[0023] Figure 4 It is the circuit diagram of the photoelectric switch sensor module;

[0024] Figure 5 It is the flow chart of eyepiece plate resetting and eyepiece replacement;

[0025] In the figure: 1. eyepiece plate; 11. eyepiece positioning hole; 12. eyepiece plate reset hole; 13. eyepiece mounting hole; 2. photoelectric switch sensor module; 3. eyepiece plate fixing plate; 4. eyepiece selection plate; 5. stepper motor. DETAILED DESCRIPTION

[0026] The technical solution of the utility model is further described below through specific embodiments.

[0027] Example

[0028] like Figure 1As shown, in this embodiment, 8 centrally symmetrical eyepiece mounting holes 13 are provided on the eyepiece plate 1 to meet the needs of different eyepieces. When eight pairs of eyepieces are fixed on the left and right eyepiece plates 1, each pair of eyepieces must meet the symmetry requirements of the left and right eyepiece plates at the corresponding positions. A light-through hole is punched on the symmetry axis of two adjacent eyepiece mounting holes 13 and close to the edge of the eyepiece plate 1 as the eyepiece positioning hole 11. It is required that the circular ring where the eyepiece positioning hole 11 is located and the circular ring where the eyepiece mounting hole 13 is located cannot overlap, so that when the eyepiece plate rotates, the infrared light of the photoelectric switch sensor can pass through each eyepiece positioning hole 11, but will not pass through the eyepiece mounting hole 13, so as to avoid the eyepiece mounting hole 13 affecting the conduction and shielding of the photoelectric switch sensor. There are 8 eyepiece positioning holes 11 in total, and the intervals between two adjacent eyepiece positioning holes 11 are the same. A similar light-through hole is added to the circle where the eight eyepiece positioning holes 11 are located, and is closer to the eyepiece positioning hole 11 in the counterclockwise direction. The structures of the left and right eyepiece discs 1 are exactly the same, and is used as the eyepiece disc reset hole 12, which is used to determine the reset point of the eyepiece disc 1, and is used to number the eyepiece positioning holes 11. The eyepiece positioning hole 11 closest to the eyepiece disc reset hole 12 is numbered as positioning hole No. 1. When the infrared light of the photoelectric switch sensor passes through this positioning hole, the position at this time is the reset point, and the reset eyepiece is facing the light-through hole of the eyepiece selection plate 4.

[0029] like Figure 2 and Figure 3 As shown, the eyepiece disc 1 is mounted on the front of the eyepiece disc fixing plate 3, and is connected by a roller, so that the eyepiece disc 1 can rotate on the eyepiece disc fixing plate 3. The stepper motor 5 is fixedly arranged on the back of the eyepiece disc fixing plate 3, and is meshed with the outer edge teeth of the eyepiece disc 1 through a double gear. The rotation of the stepper motor 5 can drive the eyepiece disc 1 to rotate; the photoelectric switch sensor module 2 is fixed on one side of the eyepiece disc fixing plate 3 to ensure that the eyepiece disc 1 can block the photoelectric switch sensor. The eyepiece selection plate 4 is fixed on the eyepiece disc fixing plate 3 and is located on the front of the eyepiece disc 1 without contact. It contains a light hole slightly larger than the eyepiece, which provides an accurate position for the eyepiece, that is, the position of the human eye. The left and right structures meet the symmetry requirements when installed.

[0030] like Figure 1-3 As shown, an eyepiece disk positioning control device that does not rely on an encoder includes an eyepiece disk 1, a photoelectric switch sensor module 2 and a main control board. The eyepiece disk 1 is provided with a plurality of eyepiece positioning holes 11 equidistantly arranged around a circular array. The eyepiece disk 1 is provided with an eyepiece disk reset hole 12, which is arranged on the circular array track of the eyepiece positioning holes 11. The setting positions of the infrared emitting diode and the phototransistor base of the photoelectric switch sensor match the setting tracks of the eyepiece positioning hole 11 and the reset hole of the eyepiece disk 1, and the photoelectric switch sensor module 2 is connected to the main control board circuit.

[0031] The number of the eyepiece positioning holes 11 is the same as the number of the eyepiece mounting holes 13 arranged on the eyepiece plate 1 , and the eyepiece positioning holes 11 and the eyepiece mounting holes 13 are arranged in a one-to-one correspondence.

[0032] like Figure 5 As shown, in this embodiment, taking the case where the number of eyepiece mounting holes 13 is 8 as an example, when the device is started or the eyepiece disk 1 needs to be reset actively, the main control board turns on the external interrupt flag of the eyepiece disk reset program, and then the stepper motor drive module drives the stepper motor 5 to rotate clockwise at a certain speed, and drives the eyepiece disk 1 to rotate clockwise through the double gears.

[0033] After the program starts to execute, when the infrared light of the photoelectric switch sensor module 2 passes through the light hole of the eyepiece disk 1 for the first time, a certain pull-up input pin of the main control board will become low level, triggering an external interrupt to start timing, until the infrared light of the photoelectric switch sensor passes through the light hole next time, triggering an external interrupt again to stop the last timing. Since the speed of the stepper motor 5 remains unchanged, the intervals between the two adjacent eyepiece positioning holes 11 on the eyepiece disk 1 are the same, the eyepiece disk reset hole 12 is closer to the eyepiece positioning hole 11 No. 1, and farther from the eyepiece positioning hole 11 on the other side, so the photoelectric switch sensor passes through the two adjacent eyepiece positioning holes 11 The longest time, recorded as t1, the time between the eyepiece disk reset hole 12 and the No. 1 positioning hole is shorter, recorded as t3, and the time between the eyepiece disk reset hole 12 and the eyepiece positioning hole 11 on the other side is longer, recorded as t2. When this timing is equal to the shorter time t3, since the eyepiece disc 1 rotates clockwise, the photoelectric switch sensor turns from the eyepiece disc reset hole 12 to the No. 1 positioning hole. At this time, the reset eyepiece is facing the light hole of the eyepiece selection plate 4, and the reset point is reached, and the eyepiece disc reset program ends; if this timing is not equal to the shorter time t3, the stepper motor 5 continues to rotate forward and starts a new timing until it reaches the reset point. Since the structures of the left and right eyepiece discs 1 are exactly the same, the rotation directions of the left and right eyepiece discs 1 are exactly the same when they are reset. The position of the right eyepiece disc 1 is the eyepiece disc reset position. At this time, the infrared light of the photoelectric switch sensor passes through the No. 1 positioning hole, and the light hole of the eyepiece selection plate 4 faces the reset eyepiece. After the eyepiece disc is reset, the reset eyepiece corresponding to the No. 1 positioning hole is in use, and the position information is recorded as 1 to ensure that there is position information at every moment.

[0034] In this embodiment, taking the eyepiece disks corresponding to the left and right as an example, the 8 eyepieces of each eyepiece disk 1 are numbered, and the reset eyepiece is recorded as eyepiece No. 1. For the right eyepiece disk 1, they are numbered from 1 to 8 in a clockwise direction starting from the reset eyepiece. Since the eyepieces of the left and right eyepiece disks are symmetrically fixed, the eyepieces on the left are numbered in the same way in a counterclockwise direction, and the number of the eyepiece currently in use, i.e., the eyepiece located at the eyepiece selection plate 4, is used as the position information.

[0035] When the eyepiece needs to be replaced, take the right eyepiece disk 1 as an example, determine the distance between the position information of the current eyepiece and the position information of the target eyepiece, and take the shortest distance to determine the rotation direction and rotation distance. Specifically, the target eyepiece position information minus the current eyepiece position information is recorded as n. If the result n is a negative number, add 8 to the result n. The result n after processing is the number of eyepieces that the right eyepiece disk 1 needs to rotate counterclockwise to the target eyepiece. When n is less than 4, the right eyepiece disk 1 rotates counterclockwise through n eyepieces. In other cases, the right eyepiece disk 1 rotates clockwise for a shorter distance, and the right eyepiece disk 1 rotates clockwise through 8-n eyepieces. The left eyepiece disk 1 rotates in the opposite direction according to this judgment method.

[0036] Regarding the judgment of the position of the eyepiece disk 1, when the eyepiece needs to be replaced, the trigger external interrupt flag is turned on and the timing is started. The stepper motor 5 drives the eyepiece disk 1 to start rotating in the direction of the shortest calculated distance. When the infrared light of the photoelectric switch sensor passes through the next light-through hole, the next interrupt is triggered to determine whether the time used is the above-mentioned maximum time t1. If so, the next eyepiece has been replaced; if not, it means that the light-through hole here is the eyepiece disk reset hole 12, and the stepper motor 5 continues to rotate, and the timing continues based on this time used. When the time used is equal to the maximum time t1, it can be seen that the next eyepiece has been replaced, and a new timing is started. The above process is repeated until the target eyepiece is replaced, the position information of the current eyepiece is updated, and the eyepiece replacement program ends.

[0037] Furthermore, when replacing the eyepiece, the total time required for replacing the eyepiece can be calculated, that is, the product of the number of eyepiece turns required and the above-mentioned maximum time t1. When the cumulative time used to trigger the interrupt is equal to the total time used, the eyepiece replacement is completed.

[0038] Preferably, due to factors such as step loss of the stepper motor 5, structural gaps and the extremely short time required for program operation, it is inevitable that there will be a certain small error between the time judged by the program and the calibrated rotation time. Therefore, the time judgment after each interruption can be slightly extended to the left and right by 5 milliseconds to become a time period, and the time periods that can be used by the program cannot overlap.

[0039] Preferably, the position of the eyepiece disc reset hole 12 can be adjusted, and the spacing of the above-mentioned three-segment eyepiece disc light-through holes can be set from small to large according to 1:2:3. If so, the above-mentioned longest time t1 is equal to 3 times the shorter time t3, and the longer time t2 is 2 times the shorter time t3, unifying the time variables and facilitating the measurement and setting of time.

[0040] In order to avoid external environmental interference, the phototransistor adopts NPN silicon phototransistor, and the infrared emitting diode and NPN silicon phototransistor are arranged side by side in the housing of the photoelectric switch sensor module 2, and the base of the infrared emitting diode and the NPN silicon phototransistor are arranged correspondingly. Among them, the housing adopts black opaque material.

[0041] In this embodiment, the phototransistor is an NPN silicon phototransistor, such as Figure 4 As shown in the middle block 1, the photoelectric switch sensor consists of an infrared emitting diode and an NPN silicon phototransistor, which are packaged side by side in a black thermoplastic housing to converge the light axis. The NPN silicon phototransistor only receives radiation from the infrared LED. The photoelectric switch sensor module 2 connects one of the two pins of the infrared emitting diode at one end to a small resistance resistor in series and then connects the power supply voltage, that is, the positive electrode of the diode is connected to a high level and the negative electrode is connected to a low level, so that it works, and the emitter of the NPN silicon phototransistor at the other end is connected to a low level, and the collector of the NPN silicon phototransistor is used as the output electrode.

[0042] When the photoelectric switch sensor module 2 is working, when there is no obstruction between the infrared emitting diode and the NPN silicon phototransistor, the infrared light emitted by the infrared emitting diode can irradiate the base of the NPN silicon phototransistor, turning on the NPN silicon phototransistor, and the saturation voltage drop between the collector and the emitter is 0.4V, the output end is at a low level, and the LED indicator lights up; when the infrared emitting diode and the NPN silicon phototransistor are blocked, the NPN silicon phototransistor is cut off, the output end is pulled up to a high level, and the LED indicator goes out.

[0043] In order to avoid the problem that the output signal of the photoelectric switch sensor output end is disturbed by the environment and jumps, such as Figure 4 As shown in the middle block 2, a Schmitt trigger is connected to the output end of the photoelectric switch sensor. Only when the output signal changes beyond a certain range can the high and low level changes occur, thereby improving the stability of the signal.

[0044] like Figure 4 As shown in the middle block 3, the interfaces of the photoelectric switch sensor module 2 are respectively high level, output end and low level, which provide power for the module and perform signal transmission.

[0045] like Figure 4 As shown in the middle block 4, an interface installed on the main control board is used to receive high and low level signals from the photoelectric switch sensor module and to power the module. The signal input end of the interface is connected to a low level through a low-capacitance bidirectional diode to play a role in electrostatic protection.

[0046] The above is a detailed description of the embodiments of the utility model, but the above contents are only preferred embodiments of the utility model and cannot be considered to limit the scope of implementation of the utility model. All equivalent changes and improvements made within the scope of application of the utility model should still fall within the scope of the patent coverage of the utility model.

Claims

1. An eyepiece disk positioning control device that does not rely on an encoder, characterized in that: The invention comprises an eyepiece plate, a photoelectric switch sensor module and a main control board. The eyepiece plate is provided with a plurality of eyepiece positioning holes equidistantly arranged around a circular array. The eyepiece plate is provided with an eyepiece plate reset hole, which is arranged on the circular array track of the eyepiece positioning holes. A photoelectric switch sensor is arranged in the photoelectric switch sensor module. The setting position of the photoelectric switch sensor matches the setting track of the eyepiece positioning hole and the eyepiece plate reset hole. The photoelectric switch sensor module is connected with the main control board circuit.

2. The eyepiece disk positioning control device independent of encoder according to claim 1, characterized in that: The photoelectric switch sensor comprises an infrared emitting diode and a phototransistor, the infrared emitting diode and the phototransistor are arranged side by side in the housing of the photoelectric switch sensor module, and the bases of the infrared emitting diode and the phototransistor are arranged correspondingly.

3. The eyepiece disk positioning control device independent of encoder according to claim 2, characterized in that: The emitter of the phototransistor is connected to a low level, the collector of the phototransistor is connected to the infrared emitting diode circuit as an output pole, and any one of the two pins of the infrared emitting diode is connected to the power supply voltage after being connected in series with a small resistance resistor.

4. The eyepiece disk positioning control device independent of encoder according to claim 3, characterized in that: The output terminal of the photoelectric switch sensor emitter is connected to a Schmitt trigger.

5. The eyepiece disk positioning control device independent of encoder according to claim 3, characterized in that: The pins of the main control board's interface for receiving high and low level signals from the photoelectric switch sensor module and the signal input pins of the photoelectric switch sensor module's power supply interface are connected to the low level through a low-capacitance bidirectional diode.

6. The eyepiece disk positioning control device independent of encoder according to claim 1, characterized in that: The number of the eyepiece positioning holes is the same as the number of the eyepiece mounting holes arranged on the eyepiece plate, and the eyepiece positioning holes correspond to the arrangement positions of the eyepiece mounting holes one by one.

7. The eyepiece disk positioning control device independent of encoder according to claim 1, characterized in that: The distance ratio between the eyepiece disc reset hole and the setting track of two adjacent eyepiece positioning holes is 1:

2.

8. The eyepiece disk positioning control device independent of encoder according to claim 1, characterized in that: The number of the eyepiece discs is two, and the installation positions of the two eyepiece discs are arranged opposite to each other on the left and right.

9. The eyepiece disk positioning control device independent of encoder according to claim 6, characterized in that: The number of eyepiece mounting holes is 8.

Images