JP2005156374A - Method and apparatus for evaluating gear frequency transmission characteristics - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for evaluating frequency transmission characteristics through the engagement of gears, allowing the evaluation of the frequency transmission characteristics of gears using a motor and a vibration exciter of a real machine so that the vibration characteristics do not change. <P>SOLUTION: The apparatus for evaluating gear frequency transmission characteristics, comprising a driven shaft to which a gear to be evaluated is attached, a drive shaft to which a drive gear engaging with the gear to be evaluated is attached, and rotation detectors which generate rotation signals for predetermined rotation angles and are attached to the driven shaft and the drive shaft, evaluates the frequency transmission characteristics of the gear to be evaluated through the difference in the signal outputs. The apparatus comprises translational excition means which minutely excites either the gear to be evaluated or the drive gear in the translational direction, rotational uneveness calculating means which determines the rotational transmission errors between the drive shaft and the driven shaft, and gear frequency transmission characteristics evaluating means which calculates the transmission characteristics from the relationship between the exciting force and the value of the rotational uneveness in the exciting frequency. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method and an apparatus for evaluating a frequency transmission characteristic by meshing of gears, and in particular, a gear frequency transmission characteristic for evaluating a frequency transmission characteristic of a practical gear that affects a rotational characteristic by a simple method. The present invention relates to an evaluation method and apparatus.

In general, in a design process and an inspection process in a wide range of fields such as information equipment (copiers, printers, etc.), home appliances, robots, etc., which are precision machine products using a gear mechanism system, a driven shaft to which an evaluation gear is attached, A method is known in which a rotation detector that generates a rotation signal at each fixed rotation angle is attached to a drive shaft that is attached to a drive gear that meshes with an evaluation gear, and a gear error is obtained from the difference in signal output.
The prior art includes: JP 2003-98005 "Evaluation test method of gear noise of gear motor" (Applying excitation torque to shaft without rotating gear, applying static load on other shaft, measuring vibration and sound of each part Method), 2. 2. Japanese Patent Laid-Open No. 2001-255240 “Plastic Gear Performance Testing Method and Apparatus” (Method of removing eccentric component of reference gear by changing gear meshing position (phase)) JP 2001-264216 "Gear evaluation method and recording medium recording gear evaluation analysis program and gear evaluation apparatus" (measurement of rotation angle on driving side and driven side, obtaining transmission error from the difference, and evaluating gear Method).
JP2003-98005 JP 2001-255240 A JP 2000-264216 A

However, the conventional technique has the following problems.
That is, in Japanese Patent Laid-Open No. 2003-98005, a method for evaluating the frequency transfer characteristic in a certain meshing state is proposed, but the measured meshing state is the same as the meshing state of other teeth. Assuming that, this evaluation method suffices, but the tooth surface accuracy of the gears is not the same for all teeth, and the meshing state changes with the rotation angle (when the meshing rate is 3.5, the three-tooth meshing In such a case, a problem arises.
In the case of Japanese Patent Laid-Open No. 2001-255240, a rotation transfer characteristic from which an eccentric component is removed can be obtained. However, in order to measure the frequency transfer characteristic, there is a change in the meshing position, and the frequency transfer characteristic evaluation is performed for each frequency. Had the disadvantage of being unsuitable.
In the case of Japanese Patent Laid-Open No. 2000-264216 (including general evaluation methods), a sensor is attached to the drive shaft and the driven shaft, and a transmission error is obtained from the difference between them. The value changes. This is due to the vibration characteristics of the gear system, and there is a problem that the speed unevenness becomes large at the rotational speed near the resonance or becomes smaller at the rotational speed near the anti-resonance. Such a conventional method is sufficient for evaluating the characteristics of only the specified rotational speed. However, in order to obtain a more accurate rotational characteristic, the frequency characteristic is evaluated and the region where the speed unevenness becomes large (near the resonance) ), It is necessary to take measures such as taking measures against the frequency characteristics.
As described above, in the conventional technique, evaluation is performed under certain limited conditions (engagement position, rotation speed), and frequency transfer characteristics that affect rotation unevenness cannot be appropriately evaluated. In addition, there is a general method for evaluating the frequency transfer characteristics by applying periodic fluctuation torque to the drive motor. In this case, however, a higher output motor is required as the frequency becomes higher. There is a problem that can not be handled. In addition, there may be a case where a large motor cannot be attached and evaluated due to the restriction of the distance between the axes of the driving gear and the driven gear.

The present invention has been made in order to solve the above-described conventional problems, and its object is to add an actual motor to the motor so that the vibration characteristics do not change without using a high-output motor that is burdensome on the environment. An object of the present invention is to provide a method and an apparatus for evaluating frequency transfer characteristics by meshing of gears, which can evaluate the frequency transfer characteristics of gears using a vibrator.
Another object of the present invention is to improve the measurement accuracy by measuring the vibration characteristics of the gear drive system in a state close to that of an actual machine.
Furthermore, another object of the present invention is to efficiently use translational excitation force and reduce power consumption at the time of evaluation.
Furthermore, another object of the present invention is to provide a space-saving evaluation method capable of evaluating frequency transfer characteristics even when a vibration exciter cannot be installed in the height direction in a helical gear.
Furthermore, another object of the present invention is to prevent the measurement accuracy from being lowered due to separation of tooth surfaces during evaluation rotation.
Furthermore, another object of the present invention is to prevent the measurement accuracy from being lowered due to separation of tooth surfaces during evaluation rotation.
Another object of the present invention is to efficiently transmit the translational excitation force to the tooth surface contact portion and reduce the power consumption of the vibrator.
Another object of the present invention is to prevent gears and devices from being damaged by resonance during evaluation of frequency transfer characteristics.
Furthermore, another object of the present invention is to provide a method that can be evaluated up to a high frequency band, can cope with a minute excitation force, and can be evaluated with less power.
Furthermore, another object of the present invention is to provide an apparatus for evaluating the frequency transfer characteristics of gears using an actual motor and a vibration exciter without using a high-output motor that places a burden on the environment.

In order to achieve the above-described object, according to the first aspect of the present invention, a rotation signal is generated for each fixed rotation angle on the driven shaft to which the evaluation gear is attached and the drive shaft to which the drive gear meshing with the evaluation gear is attached. In the gear frequency transmission characteristic evaluation method for attaching a rotation detector and evaluating the frequency transmission characteristic of the evaluation gear from the difference between the signal outputs, either one of the evaluation gear and the drive gear is slightly excited in the translation direction. A translational vibration step, a rotation unevenness calculating step for obtaining a rotation transmission error between the drive shaft and the driven shaft, and a gear frequency transmission characteristic evaluation for calculating a transfer characteristic from the relationship between the excitation force and the rotation unevenness value at the vibration frequency. It is characterized by comprising a process.
The invention according to claim 2 is characterized in that the translational excitation is applied to the drive gear.
The invention according to claim 3 is characterized in that the direction of the translational excitation is adjusted to a pressure angle which is a direction of a line of action with which the gear is engaged.
According to a fourth aspect of the present invention, the gear is a helical gear, and the translational excitation direction is an axial direction.
The invention according to claim 5 is characterized in that a load mechanism by friction or the like is attached to the driven shaft to which the evaluation gear is attached.
The invention according to claim 6 is characterized in that the excitation force in the translation direction is set smaller than the meshing force of the gear.
The invention according to claim 7 is characterized in that the translational excitation is applied to a bearing provided on the shaft, and the bearing is supported by an elastic body.
The invention according to claim 8 is characterized in that when the backlash amount of the gear is equal to the rotational unevenness amount of the excitation frequency, the excitation force is reduced in level.
The invention according to claim 9 is characterized in that an acceleration sensor is attached to the non-translational bearing portion, and the transfer characteristic is calculated in consideration of the rotation unevenness characteristic.
According to a tenth aspect of the present invention, a rotation detector for generating a rotation signal for each fixed rotation angle is attached to the driven shaft to which the evaluation gear is attached and the drive shaft to which the drive gear meshing with the evaluation gear is attached. In the gear frequency transmission characteristic evaluation apparatus for evaluating the frequency transmission characteristic of the evaluation gear from the difference in signal output, the translational excitation means for minutely exciting either the evaluation gear or the drive gear in the translational direction, and the drive A rotation unevenness calculating means for calculating a rotation transmission error between the shaft and the driven shaft, and a gear frequency transfer characteristic evaluating means for calculating a transfer characteristic from the relationship between the excitation force at the excitation frequency and the rotation unevenness value. Features.

According to the present invention, a rotation detector that generates a rotation signal (rectangular wave signal) for each fixed rotation angle is attached to the driven shaft to which the evaluation gear is attached and the drive shaft to which the drive gear meshing with the evaluation gear is attached, The evaluation method of the gear frequency transmission characteristic that evaluates the frequency transmission characteristic of the evaluation gear from the difference of the signal output is a translational excitation process that can slightly excite the gear in the translational direction, and a rotation transmission error between the drive shaft and the driven shaft. The rotation unevenness calculating step for calculating the transmission frequency and the gear frequency transfer characteristic evaluating step for calculating the transfer characteristic from the relationship between the excitation force and the rotation unevenness value at the excitation frequency. The vibration force oscillates the entire gear in the translational direction and is transmitted to the other shaft through the meshing teeth, and as a result, detected as rotation unevenness. When the transmission characteristic of the tooth portion is low, vibrations in the vibration exciter are absorbed and speed unevenness at the vibration frequency is not detected. In this way, the frequency transfer characteristic at the tooth portion corresponding to the excitation frequency can be evaluated. As a result, it is possible to evaluate the frequency transfer characteristics of the gears with a simple configuration using a real motor and a vibration exciter without using a high-output motor that places a burden on the environment.
According to another invention, the translational excitation of the gear is as a drive shaft gear, so that the drive shaft side is subjected to translational excitation with the motor even when various accessory parts are attached to the driven shaft. Therefore, evaluation can be performed without removing the accessory parts of the driven shaft. As a result, the vibration characteristics of the gear drive system can be measured in a state close to that of an actual machine, and improvement in measurement accuracy can be provided.
According to another invention, the translational excitation force is made normal to the tooth surface contact portion by adjusting the direction of the translational excitation to the pressure angle that is the direction of the line of engagement of the gears. It can be made parallel to the direction, and the load applied to the bearing on the excitation side can be minimized. As a result, the translational excitation force can be used efficiently, and a reduction in power consumption at the time of evaluation can be provided.
According to another invention, the gear is a helical gear and the translational excitation direction is an axial direction, so that a translational excitation force corresponding to the helical angle of the helical gear can be applied. As a result, in a helical gear, it is possible to provide a space-saving evaluation method that can evaluate frequency transfer characteristics even when a vibrator cannot be installed in the height direction.
According to another invention, the driven shaft to which the evaluation gear is attached is attached with a load mechanism by friction or the like, thereby preventing a phenomenon in which tooth surfaces jump from each other due to the excitation force of the shaker. can do. As a result, tooth surfaces are separated from each other and rotation unevenness measurement accuracy is prevented from decreasing. It can be evaluated with high accuracy.
According to another invention, the exciting force in the translational direction is set to be smaller than the meshing force of the gear, thereby preventing a phenomenon in which tooth surfaces jump from each other due to the exciting force of the vibrator. can do. As a result, tooth surfaces are separated from each other and rotation unevenness measurement accuracy is prevented from decreasing. It can be evaluated with high accuracy.
According to another aspect of the invention, the translational excitation is applied to the bearing, and the bearing is supported by the elastic body, so that the target gear unit can be shaken by the excitation force of the shaker. As a result, the translational excitation force can be efficiently transmitted to the tooth surface contact portion, and the power consumption of the shaker can be reduced.

According to another invention, when the backlash amount of the gear and the rotation unevenness amount of the excitation frequency become equal, abnormal vibration of the tooth surface can be avoided by lowering the excitation force. As a result, it is possible to prevent damage to the gears and the device depending on the resonance state during evaluation of the frequency transfer characteristics.
Further, according to another invention, an acceleration sensor is attached to the non-translational bearing part, and the transfer characteristic is calculated in consideration of the rotation unevenness characteristic. Thus, even when rotation unevenness at the excitation frequency cannot be measured, evaluation can be performed by substituting the output of the acceleration sensor. As a result, it is possible to evaluate up to a high frequency band, and it is possible to cope with a minute excitation force, and it is possible to evaluate with a small amount of power.
According to another invention, a rotation detector that generates a rotation signal (rectangular wave signal) for each fixed rotation angle on a driven shaft to which an evaluation gear is attached and a drive shaft to which a drive gear meshing with the evaluation gear is attached. In the gear frequency transmission characteristic evaluation apparatus that evaluates the frequency transmission characteristic of the evaluation gear from the difference between the signal outputs, the translational excitation means that can slightly excite the gear in the translational direction, and the drive shaft and the driven shaft It is composed of a rotation unevenness calculating means for obtaining a rotation transfer error, and a gear frequency transfer characteristic evaluating means for calculating a transfer characteristic from the relationship between the excitation force and the rotation unevenness value at the excitation frequency. Exciting force corresponding to sway the entire gear in the translational direction and is transmitted to the other shaft through the meshing teeth, and as a result, detected as rotation unevenness. When the transmission characteristic of the tooth portion is low, vibrations in the vibration exciter are absorbed and speed unevenness at the vibration frequency is not detected. In this way, the frequency transfer characteristic at the tooth portion corresponding to the excitation frequency can be evaluated. As a result, it is possible to provide a device that can evaluate the frequency transfer characteristics of a gear with a simple configuration using a real motor and a vibration exciter without using a high-output motor that places a burden on the environment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic configuration diagram of an embodiment of a gear frequency transfer characteristic evaluation apparatus according to the present invention.
As shown in FIG. 1, this gear frequency transfer characteristic evaluation apparatus includes a drive gear 5 attached to a drive shaft 3 from a motor 1 and a driven gear (attached to a driven shaft 9 from a component 7 such as a photosensitive drum. A gear frequency transmission characteristic with respect to the evaluation gear) 11 is evaluated. A central processing unit (CPU) 13, a random access memory (RAM) 15, a CRT (Cathode Ray Tube) 17 of a display display, an input Keyboard 19 and mouse 21, a printer 23 for outputting evaluation results, etc., an OS (Operating System) for basic control of the CPU 13, and a magnetic disk device (HDD: Hard Disk Drive) in which an evaluation program as the gist of the present invention is stored ) 25, A / D, D / A 27, counter 29, evaluation computer 33 comprising an internal bus 31 for connecting them, and a photosensitive drum, etc. An exciter 35 for applying an excitation force in the translational direction to the driven gear 11 attached to the driven shaft 9 from the product 7, and the drive shaft 3 and the drive shaft 3 so as to generate a rotation signal (rectangular wave signal) at every fixed rotation angle. And encoders (rotation detectors) 37 and 39 attached to the driven shaft 9.
The outputs of the encoders 37 and 39 attached to the drive shaft 3 and the driven shaft 9 are input to the evaluation computer 33 side through the counter 29. Further, a speed command and a vibration force command at a frequency set in the shaker 35 so as to obtain a rotation speed set in the drive motor 1 through the A / D and D / A 27 from the computer 33 side will be described later. A load command is given to the load brake on the driven shaft. The evaluation result is temporarily stored in a RAM (Random Access Memory) 15.
By executing the gear frequency transfer characteristic evaluation program described below in such a configuration, a practical frequency transfer characteristic of the gear can be obtained under conditions close to those of an actual machine, and information useful in the design process and the inspection process can be obtained by CRT and It can be supplied from printed paper.

Next, a gear frequency transfer characteristic evaluation method using the gear frequency transfer characteristic evaluation apparatus shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a flowchart of the frequency transfer characteristic evaluation method embodying the present invention.
As a procedure of the evaluation method, in step 101 of FIG. 2, the frequency region, the rotation speed, and the excitation force (or excitation amplitude) that are the evaluation conditions are input to the evaluation computer 33, where, according to the input conditions, The motor 1 on the drive shaft 3 is rotated, and an excitation force is applied to a driven gear 11 attached to a driven shaft 9 from a component 7 such as a photosensitive drum, so that the driven gear 11 is slightly excited. Next, in step 103, the frequency to be vibrated by the shaker 35 is automatically set in the evaluation computer 33. Here, the frequency is gradually shifted from a low frequency to a high frequency in a region determined by the evaluation condition, but a reverse pattern may be used.
Next, in the gear drive measurement in step 105, the difference between the encoders 37 and 39 on the drive shaft 3 and the driven shaft 9 (in consideration of the reduction ratio) in the state driven by the motor 1 and vibrated by the shaker 35. Thus, a rotation error (rotation unevenness = speed unevenness) is obtained. The measurement time for each frequency is set to be longer than the time required for the driven gear 11 to make one rotation. This uneven rotation includes various factors such as those caused by gear shape accuracy and eccentricity, and those caused by speed unevenness of the drive motor 1. Here, paying attention to the excited frequency, rotation unevenness (difference between encoders 37 and 39 output) at this frequency component is calculated (step 107).
Next, in step 109, the rotation unevenness at the excitation frequency is divided by the excitation force (or excitation amplitude), and the transfer characteristic at the excitation frequency is calculated. After that, in step 111, it is checked whether to change the excitation frequency. If all the excitation frequency regions set in the evaluation conditions are not completed, the process returns to step 103 again to shift the excitation frequency. Proceed with the same evaluation. Next, when the measurement is completed in all the excitation frequency regions, in step 113, the transfer characteristics for each of the excited frequencies are output in a graph or the like, and the frequency transfer characteristic evaluation is completed.
FIG. 3 is a graph showing an example of a result of evaluation by the frequency transfer characteristic evaluation method shown in FIG. Depending on the excitation frequency, it can be confirmed that the transfer characteristic is large (resonance point) and small (anti-resonance point).

FIG. 4 shows a case (a) in which a rotational force (prior art) is applied to the driven gear 11 and a case (B) in which a vibration force F (present invention) in the translational direction A is applied to the driven gear 11. It is explanatory drawing of. If the force and amplitude of the excitation frequency are applied to the tooth contact surface and it can be evaluated how it is transmitted to the gear on the opposite side, the frequency transfer characteristic can be obtained. Therefore, when the tooth surface contact surface is vibrated, the exciting force F (the present invention) is applied in the translational direction A, rather than applying the exciting force in the rotational direction while rotating at a constant rotational speed (prior art). It is possible to use the motor and control system of the actual machine as is (divided into the rotational force at a constant rotational speed and the translational force that vibrates the tooth surface) (the vibration characteristics of the actual machine can be evaluated), and a dedicated vibrator This is advantageous in that the controller can be used (evaluation is possible up to a high frequency range).
As described above, according to the frequency transfer characteristic evaluation method embodying the present invention, the excitation force corresponding to the frequency from the shaker shakes the entire gear in the translational direction, and passes to the other shaft through the meshed teeth. As a result, rotation unevenness is detected. When the transmission characteristic of the tooth portion is low, vibrations in the vibration exciter are absorbed and speed unevenness at the vibration frequency is not detected. In this way, the frequency transfer characteristic at the tooth portion corresponding to the excitation frequency can be evaluated. As a result, it is possible to evaluate the frequency transfer characteristics of the gears with a simple configuration using a real motor and a vibration exciter without using a high-output motor that places a burden on the environment.

FIG. 5 is an explanatory view showing an embodiment in which translational excitation is applied to the drive gear 5 side. As shown in FIG. 5, even when various accessory parts are attached to the driven shaft 9 by exciting the drive side gear 5 with the excitation force F in the translational direction A, the evaluation can be performed without removing the accessory parts. Yes. In the case of an image forming apparatus, components such as a photosensitive drum are attached to the driven shaft, and if this is removed, the inertia term (moment of inertia) of the driven shaft changes and the frequency transfer characteristics cannot be evaluated properly. Further, if it is carried out while being attached, the photosensitive drum also vibrates in translation, which may come into contact with peripheral devices and be damaged. Therefore, by giving translational excitation to the drive gear 5 side in this way, this can be avoided and the frequency transfer characteristic can be evaluated in a state close to that of the actual machine.
FIG. 6 is an explanatory diagram showing an embodiment in which the ratio of the tooth surface normal force Fa in the translational force F in the translation direction is increased. Here, since the exciting force F in the translational direction is divided into the tooth surface normal force Fa and the tooth surface friction force Fb, the former can be used effectively by increasing the proportion of the former necessary for frequency transfer characteristic evaluation. (See FIG. 6A). Since the latter becomes a frictional force and generates heat, it is better to reduce it as much as possible. Therefore, in the embodiment shown in FIG. 6, the direction of excitation is adjusted to the pressure angle that is the direction of the line of action with which the gear is engaged (see FIG. 6B). This makes it possible to perform evaluation while suppressing heat generation, and is advantageous in the case where characteristics change greatly with temperature, such as a resin gear (dimensional change due to thermal expansion, elastic modulus change due to temperature).
FIG. 7 is an explanatory view showing an embodiment using a helical gear. As shown in FIG. 7B, in the case of a helical gear, the tooth surface normal force Fa is distributed in the axial direction Fc and the circumferential direction Fd according to the twist angle β. Therefore, as shown in FIG. 7A, in this embodiment, the entire target gear is vibrated in the direction of the driven shaft 9, so that the tooth surface is also vibrated, and this is used to evaluate the frequency transfer characteristic. To do. In the case where there is no space for installing a vibrator in the vertical direction of the gear, the evaluation can be performed in this way. As the twist angle β is larger, the energy of the vibrator is more easily transmitted to the tooth surface. Therefore, the larger β is, the smaller the energy consumption required for the evaluation is.

FIG. 8 is a configuration diagram of an embodiment in which a brake as a load mechanism by friction or the like is attached to a driven shaft to which an evaluation gear is attached. When the excitation force is large or when the excitation frequency becomes high, there are cases where the gear tooth surfaces that are in contact jump and leave (tooth separation). This appears as rotation unevenness as it is and affects the transmission characteristics, so it must be avoided. Therefore, in this embodiment, as shown in FIG. 8, a brake 41 as a load mechanism by friction or the like is attached to the driven shaft 9 to which the evaluation gear 11 is attached. Thereby, it is possible to prevent the tooth surfaces from jumping due to the excitation force of the vibration exciter, to prevent the tooth surfaces from separating from each other and to reduce the rotational unevenness measurement accuracy, and to evaluate with high accuracy. The size of the load is set to the size of the load applied by the actual machine, and it should not be increased more than necessary. If it is too large, the gear will be deformed and the vibration characteristic system will change.
FIG. 9 is an explanatory diagram of an embodiment in which the exciting force in the translation direction is set smaller than the meshing force of the gear. As shown in FIG. 9 (a), the driving force from the motor and the load torque on the driven shaft balance the tooth surface contact force of the gear rotating at a certain constant speed. In this state, when an excitation force is applied from the outside, the tooth surface contact force changes as shown in FIG. The frequency response is evaluated by evaluating whether force is transmitted using this change. Under such circumstances, the tooth surfaces jump out when the excitation force is at a level greater than the meshing force (balance force). Therefore, in this embodiment, in order to avoid this, The excitation force is set to be smaller than the meshing force of the gear. As a result, tooth surfaces are separated from each other and rotation unevenness measurement accuracy is prevented from decreasing. It can be evaluated with high accuracy.
FIG. 10 is an explanatory diagram of an embodiment in the case where the excitation force is directly applied to the bearing. When the frequency characteristics are evaluated by applying a periodic force to the tooth surface, as shown in FIG. 10A, when the vibration exciter 35 is attached to the base portion 43, it is affected by the base mass. That is, when the base mass is large, the vibrator 35 must vibrate together with the base, so a large output is required. On the other hand, as shown in FIG. 10B, an excitation force is directly applied to the bearing 45, and the bearing 45 is supported by the elastic body 47, so that it is not affected by the base portion 43, and the target gear unit (the rotating shaft 9) is not affected. ) Can be shaken. As a result, the translational excitation force can be efficiently transmitted to the tooth surface contact portion, and the power consumption of the shaker can be reduced.

FIG. 11 is a flowchart of an embodiment of the frequency transfer characteristic evaluation method in which the backlash amount of the gear and the rotation unevenness amount of the excitation frequency are checked, and when they become equal, the excitation force is corrected to be lowered. It is. In this embodiment of the frequency transfer characteristic evaluation method, the gear backlash may be a value (design value) from the specifications of the gear or an actual measurement value. This value is added and set in the evaluation condition input step (step 201). Thereafter, the excitation frequency and the excitation force are set (steps 203 and 205) and the evaluation is performed (steps 207 and 209), and the magnitude of the rotation unevenness and the backlash amount are compared (step 211). It is determined that the excitation force is too large (resonance region), and the excitation force is set small (step 205).
Thereafter, the rotation unevenness at the vibration frequency is divided by the vibration force (or vibration amplitude), the transfer characteristic at the vibration frequency is calculated (step 213), and it is checked whether the vibration frequency is changed (step 213). Step 215) If not all of the excitation frequency regions set in the evaluation conditions have been completed, the process returns to Step 103 again, and the same evaluation is performed by shifting the excitation frequency. When the measurement is finished, the transfer characteristic for each frequency that has been vibrated is output as a graph (step 217), and the frequency transfer characteristic evaluation is completed.
As a result, abnormal vibration of the tooth surface can be avoided, and as a result, it is possible to prevent the gears and the device from being damaged by the resonance state during evaluation of the frequency transfer characteristics.
FIG. 12 is a configuration diagram of an embodiment in which an acceleration sensor is attached to a bearing portion (drive shaft 3) that is not subjected to translational excitation, and transfer characteristics are calculated in consideration of rotation unevenness characteristics. As shown in FIG. 12, in this embodiment, an acceleration sensor 49 is attached to the bearing portion (drive shaft 3) that is not subjected to translational excitation, and the transfer characteristic is calculated in consideration of the rotation unevenness characteristic. When the excitation vibration on the driven side is transmitted through the tooth surface and reaches the driving side, it appears as vibration as well as uneven rotation. This vibration is measured by the acceleration pickup 49, and the transfer characteristic is evaluated. In this way, it is possible to evaluate even if the response at the excitation frequency cannot be measured by only the rotation unevenness due to the resolution of the rotation detector and the response speed. As a result, it is possible to evaluate up to a high frequency band, and it is possible to cope with a minute excitation force, and it is possible to evaluate with a small amount of power.

It is a schematic block diagram of one Embodiment of the gear frequency transfer characteristic evaluation apparatus by this invention. It is a flowchart of the frequency transfer characteristic evaluation method which implemented this invention. It is a graph which shows an example of the result evaluated by the frequency transfer characteristic evaluation method shown in FIG. It is explanatory drawing when the excitation force (prior art) of a rotation direction is given to the driven gear 11, and the excitation force F (this invention) of the translation direction A is given to the driven gear 11. It is explanatory drawing which shows embodiment which gives translation excitation to the drive gearwheel 5 side. It is explanatory drawing which shows embodiment which increased the ratio of the tooth surface normal force Fa in the exciting force F of a translation direction. It is explanatory drawing which shows embodiment using a helical gear. It is a block diagram of embodiment which attached the brake as a load mechanism by friction etc. to the driven shaft to which an evaluation gear wheel is attached. It is explanatory drawing of embodiment which set the exciting force of the said translation direction smaller than the meshing force of a gearwheel. It is explanatory drawing of embodiment in the case of giving an exciting force directly to a bearing. It is a flowchart of an embodiment of a frequency transfer characteristic evaluation method in which the backlash amount of the gear and the rotation unevenness amount of the excitation frequency are checked, and when they become equal, the excitation force is corrected to be lowered. FIG. 5 is a configuration diagram of an embodiment in a case where an acceleration sensor is attached to a bearing portion (drive shaft 3) that is not subjected to translational excitation, and transmission characteristics are calculated in consideration of rotation unevenness characteristics.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Motor, 3 ... Drive shaft, 5 ... Drive gear, 7 ... Parts, 9 ... Driven shaft, 11 ... Driven gear, 13 ... CPU, 19 ... Keyboard, 21 ... Mouse, 23 ... Printer, 29 ... Counter, 31 ... Internal bus 33 ... Evaluation computer 35 ... Exciter 37, 39 ... Encoder 41 ... Brake 43 ... Base part 47 ... Elastic body 49 ... Accelerometer

Claims (10)

A rotation detector that generates a rotation signal for each fixed rotation angle is attached to the driven shaft to which the evaluation gear is attached and the drive shaft to which the drive gear meshing with the evaluation gear is attached. A gear frequency transmission characteristic evaluation method for evaluating characteristics,
A translational excitation step of minutely exciting one of the evaluation gear and the drive gear in the translation direction;
A rotation unevenness calculating step for obtaining a rotation transmission error between the drive shaft and the driven shaft;
A gear frequency transfer characteristic evaluation method comprising: a gear frequency transfer characteristic evaluation step for calculating a transfer characteristic from a relationship between an excitation force and a rotation unevenness value at the excitation frequency.   The gear frequency transfer characteristic evaluation method according to claim 1, wherein the translational excitation is applied to the drive gear.   3. The method for evaluating a gear frequency transmission characteristic according to claim 1, wherein a direction of the translational excitation is set to a pressure angle that is a direction of a line of action with which the gear is engaged. .   The gear frequency transmission characteristic evaluation method according to claim 1, wherein the gear is a helical gear, and the translational excitation direction is an axial direction.   5. The gear frequency transmission characteristic evaluation method according to claim 1, wherein a load mechanism by friction or the like is attached to the driven shaft to which the evaluation gear is attached.   The gear frequency transfer characteristic evaluation method according to any one of claims 1 to 5, wherein the excitation force in the translation direction is set to be smaller than a meshing force of the gear.   7. The gear frequency transmission characteristic evaluation method according to claim 1, wherein the translational excitation is applied to a bearing provided on the shaft, and the bearing is supported by an elastic body.   8. The method for evaluating a gear frequency transmission characteristic according to claim 1, wherein when the backlash amount of the gear and the amount of rotation unevenness of the excitation frequency become equal, the excitation force is reduced in level. .   The gear frequency transmission characteristic evaluation according to any one of claims 1 to 8, wherein an acceleration sensor is attached to the non-translational vibration-bearing part, and the transmission characteristic is calculated in consideration of the rotation unevenness characteristic. Method. A rotation detector that generates a rotation signal for each fixed rotation angle is attached to the driven shaft to which the evaluation gear is attached and the drive shaft to which the drive gear meshing with the evaluation gear is attached. A gear frequency transfer characteristic evaluation device for evaluating characteristics,
Translational excitation means for minutely vibrating either one of the evaluation gear and the drive gear in the translation direction;
Rotation unevenness calculating means for obtaining a rotation transmission error between the drive shaft and the driven shaft;
A gear frequency transfer characteristic evaluation device comprising gear frequency transfer characteristic evaluation means for calculating a transfer characteristic from a relationship between an excitation force and a rotation unevenness value at the excitation frequency.

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