阅读说明：本技术 齿隙测量及调节方法、齿隙测量及调节装置 (Backlash measuring and adjusting method and backlash measuring and adjusting device ) 是由 王师 杜向红 李天天 于 2019-11-20 设计创作，主要内容包括：本发明属于测量调节技术,具体地说是一种齿隙测量及调节方法、齿隙测量及调节装置,该齿隙测量方法包括：驱动输入轴正向旋转；在某一时刻,驱动输入轴反向旋转,并同步采集输入轴的角度与时间的第一曲线波形、输出轴的角度与时间的第二曲线波形；根据得到的第一曲线波形和第二曲线波形,计算输出轴在输入轴反向旋转时的停滞时长Δt；根据停滞时长Δt,在停滞时长Δt内计算输入轴的角度变化值Δθ；根据输入轴的角度变化值Δθ,测得第一齿轮和第二齿轮之间的齿隙。同现有技术相比,提高了齿隙的测量精度。(The invention belongs to the measurement and adjustment technology, in particular to a backlash measurement and adjustment method and a backlash measurement and adjustment device, wherein the backlash measurement method comprises the following steps: driving the input shaft to rotate in the forward direction; at a certain moment, driving the input shaft to rotate reversely, and synchronously acquiring a first curve waveform of the angle and the time of the input shaft and a second curve waveform of the angle and the time of the output shaft; calculating the stagnation time delta t of the output shaft when the input shaft rotates reversely according to the obtained first curve waveform and the second curve waveform; calculating an angle change value delta theta of the input shaft within the stagnation time delta t according to the stagnation time delta t; the backlash between the first gear and the second gear is measured based on the angle change value Δ θ of the input shaft. Compared with the prior art, the measurement accuracy of the backlash is improved.)

1. A backlash measuring method, characterized by comprising the steps of:

driving the input shaft to rotate in the forward direction;

at a certain moment, driving the input shaft to rotate reversely, and synchronously acquiring a first curve waveform of the angle and the time of the input shaft and a second curve waveform of the angle and the time of the output shaft;

calculating the stagnation time delta t of the output shaft when the input shaft rotates reversely according to the obtained first curve waveform and the second curve waveform;

calculating an angle change value delta theta of the input shaft within the stagnation time delta t according to the calculated stagnation time delta t;

and measuring the backlash between a first gear connected with the input shaft and a second gear connected with the output shaft according to the calculated angle change value delta theta of the input shaft.

2. The backlash measuring method according to claim 1, wherein the step of calculating the stagnation time period Δ t of the output shaft when the input shaft rotates in the reverse direction includes:

recording a starting time point t1 of the input shaft when rotating in the reverse direction;

recording a starting time point t2 of the output shaft when rotating in the reverse direction;

calculating a difference between the t1 and the t2, and taking the difference as a stagnation time period at of the output shaft when the input shaft rotates in the reverse direction.

3. The backlash measuring method according to claim 1, wherein the step of calculating the angle change Δ θ of the input shaft within the dead time period Δ t specifically includes:

acquiring a rotation angle theta 1 of the input shaft at the initial time point of the stagnation time delta t;

acquiring a rotation angle theta 2 of the input shaft when the stagnation time delta t is finished;

and calculating an angle difference value between the theta 1 and the theta 2, and taking the angle difference value as an angle change value delta theta of the input shaft.

4. The backlash measuring method according to claim 1, wherein the step of measuring the backlash between a first gear connected to the input shaft and a second gear connected to the output shaft based on the calculated angular change value Δ θ of the input shaft specifically includes:

calculating a reduction ratio i between the input shaft and the output shaft when the output shaft rotates in a reverse direction;

substituting the calculated reduction ratio i into a formula: the backlash is measured as the reduction ratio i × the angle change value Δ θ.

5. A backlash adjustment method is characterized by comprising the following steps:

acquiring the backlash measured by the backlash measurement method according to any one of claims 1 to 4;

intercepting a current output curve of the driving end in a certain time period when the input shaft rotates at a constant speed in the forward direction or the reverse direction;

calculating a current average value of the current output curve;

judging whether the current average value and the measured backlash meet preset conditions or not;

if the axial position of the first gear connected with the input shaft relative to the second gear is judged not to meet the preset condition;

after the axial position of the first gear is adjusted, continuously executing the steps;

and if the gear backlash is judged not to meet the preset condition, the gear backlash adjustment is finished.

6. The backlash adjustment method according to claim 5, wherein the step of determining whether the average value of the current and the measured backlash satisfy a preset condition specifically includes;

if the calculated current average value is larger than a preset current value or the measured backlash is larger than a preset backlash, judging that the current average value and the measured backlash do not meet a preset condition;

and if the calculated current average value is not greater than a preset current value and the measured backlash is not greater than a preset backlash, judging that the current average value and the measured backlash meet a preset condition.

7. The backlash adjustment method according to claim 6, wherein the step of adjusting an axial position of the first gear connected to the input shaft with respect to the second gear specifically includes;

if the calculated current average value is not greater than a preset current value, but the measured backlash is greater than a preset backlash, controlling the first gear to move towards the direction of the second gear;

and if the calculated current average value is larger than a preset current value and the measured backlash is not larger than the preset backlash, controlling the first gear to move towards the direction far away from the second gear.

8. The backlash adjustment method according to any one of claims 5 to 7, wherein a value of a current output by the drive end increases as the backlash becomes smaller when the input shaft rotates at a constant speed.

9. A backlash measuring device, comprising:

the driving end is connected with the input shaft; the driving end is used for driving the input shaft to rotate in the forward direction and also used for driving the input shaft to rotate in the reverse direction at a certain moment;

the first detection module is used for synchronously detecting the rotation angle of the input shaft when the input shaft rotates reversely and outputting a first curve waveform of the angle and time;

the second detection module is used for synchronously detecting the rotation angle of the output shaft when the input shaft rotates reversely and outputting a second curve waveform of the angle and time;

the main control module is respectively in communication connection with the first detection module and the second detection module and is used for calculating the stagnation time delta t of the output shaft when the input shaft rotates reversely according to the first curve waveform and the second curve waveform;

the main control module is further used for calculating an angle change value delta theta of the input shaft within the stagnation time delta t according to the calculated stagnation time delta t, and measuring a backlash between a first gear connected with the input shaft and a second gear connected with the output shaft according to the angle change value delta theta.

10. The backlash measuring device of claim 8, wherein the first detecting module and the second detecting module are both encoders.

11. The backlash measuring device of claim 8, wherein said drive end is a servo motor connected to said input shaft.

12. A backlash adjustment device, comprising:

the current detection module is used for detecting the current value output by the driving end when the input shaft rotates forwards or reversely;

the main control module is in communication connection with the current detection module and is used for calculating the average value of output current of the input shaft during constant-speed rotation within a certain time period according to the current value detected by the current detection module; the main control module is further configured to determine whether the current average value and a backlash obtained by using the backlash measurement device according to any one of claims 9 to 11 satisfy a preset condition;

the backlash adjusting mechanism is connected with the first gear; and the backlash adjusting mechanism is used for driving a first gear connected with the input shaft to move axially relative to a second gear after the main control module judges that the current average value and the measured backlash do not meet preset conditions.

Technical Field

The invention relates to a measurement and adjustment technology, in particular to a tooth clearance measurement and adjustment method and a tooth clearance measurement and adjustment device.

Background

During a geared transmission, if the load is reversed, the output shaft will rotate a small angle, called backlash, even if the input shaft is locked, as shown in fig. 1. The proper tooth side clearance is provided when the gear teeth are meshed, so that a normal lubricating oil film is formed between the tooth surfaces, and the gear teeth are prevented from being clamped due to thermal expansion deformation caused by the increase of the working temperature of the gear. However, for the mechanism requiring more and more precise transmission, such as an industrial robot joint, the existence of backlash is easy to form errors in transmission positioning and low transmission quality and efficiency, and is easy to generate vibration and noise. Therefore, in the precise transmission mechanism, the assembled gear pair has to ensure that the tooth clearance is as small as possible on one hand and the small meshing resistance is ensured on the other hand, so that the transmission is precise, smooth and stable.

However, the traditional tooth gap measuring method generally adopts a lead wire pressing method, specifically, 2-4 lead wires are placed in parallel on a tooth surface with the tooth width, the diameter of each lead wire is not more than 4 times of the minimum gap, a rotating gear extrudes the lead wires, the thickness dimension of the thinnest part of the extruded lead wires is the tooth gap value, and the lead wires have certain hardness and irregular indentation, so that the method has larger measuring errors.

Secondly, a counter is adopted to measure the backlash, namely the output shaft is unloaded after being pre-tightened clockwise, and 2% of the rated load torque value is applied reversely. A dial indicator is used for measuring a rigid force arm arranged on the output shaft, the displacement of the rigid force arm at a certain distance from the rotation center is measured, and a corresponding rotation angle is calculated. However, the method can only measure the tooth clearance of a certain meshing position by one-time clamping, and cannot realize continuous measurement.

In addition, a carrying experiment bench is adopted to measure the backlash, namely the hysteresis curve of gear transmission, and the method mainly reflects the torsional rigidity of a gear system because 2% to 100% of rated torque needs to be additionally loaded. And the laboratory bench is relatively complex and expensive.

Disclosure of Invention

The invention aims to provide a backlash measuring and adjusting method and a backlash measuring and adjusting device, which can realize backlash measurement and backlash adjustment, improve the precision of two gears in meshing transmission after adjustment, and avoid vibration and noise of the two gears in the meshing transmission.

In order to solve the above technical problem, an embodiment of the present invention provides a backlash measuring method, including the steps of:

driving the input shaft to rotate in the forward direction;

at a certain moment, driving the input shaft to rotate reversely, and synchronously acquiring a first curve waveform of the angle and the time of the input shaft and a second curve waveform of the angle and the time of the output shaft;

calculating the stagnation time delta t of the output shaft when the input shaft rotates reversely according to the obtained first curve waveform and the second curve waveform;

calculating an angle change value delta theta of the input shaft within the stagnation time delta t according to the calculated stagnation time delta t;

and measuring the backlash between a first gear connected with the input shaft and a second gear connected with the output shaft according to the calculated angle change value delta theta of the input shaft.

In addition, the embodiment of the invention also provides a backlash adjusting method, which comprises the following steps:

acquiring the backlash measured by the backlash measurement method;

intercepting a current output curve of the driving end in a certain time period when the input shaft rotates at a constant speed in the forward direction or the reverse direction;

calculating a current average value of the current output curve;

judging whether the current average value and the measured backlash meet preset conditions or not;

if the axial position of the first gear connected with the input shaft relative to the second gear is judged not to meet the preset condition;

after the axial position of the first gear is adjusted, continuously executing the steps;

and if the gear backlash is judged not to meet the preset condition, the gear backlash adjustment is finished.

In addition, an embodiment of the present invention also provides a backlash measuring apparatus including:

the driving end is connected with the input shaft; the driving end is used for driving the input shaft to rotate in the forward direction and also used for driving the input shaft to rotate in the reverse direction at a certain moment;

the first detection module is used for synchronously detecting the rotation angle of the input shaft when the input shaft rotates reversely and outputting a first curve waveform of the angle and time;

the second detection module is used for synchronously detecting the rotation angle of the output shaft when the input shaft rotates reversely and outputting a second curve waveform of the angle and time;

the main control module is respectively in communication connection with the first detection module and the second detection module and is used for calculating the stagnation time delta t of the output shaft when the input shaft rotates reversely according to the first curve waveform and the second curve waveform;

the main control module is further used for calculating an angle change value delta theta of the input shaft within the stagnation time delta t according to the calculated stagnation time delta t, and measuring a backlash between a first gear connected with the input shaft and a second gear connected with the output shaft according to the angle change value delta theta.

In addition, an embodiment of the present invention also provides a backlash adjusting apparatus including:

the current detection module is used for detecting the average current value of the driving end in a certain time period when the input shaft rotates forwards or reversely at a constant speed;

the main control module is used for judging whether the current average value is larger than a preset current value or not and judging whether the backlash obtained by adopting the backlash measuring device according to the claim is larger than a preset backlash or not;

and the backlash adjusting mechanism is used for driving the first gear connected with the input shaft to move relative to the second gear along the axial direction.

Compared with the prior art, the backlash measuring method of the embodiment of the invention has the advantages that by means of the characteristics of the backlash, the input shaft drives the first gear to rotate in the reverse direction at a certain moment in the process of driving the input shaft to drive the first gear to rotate in the forward direction, and at the initial stage of the reverse rotation of the input shaft, the output shaft can generate the backlash with the input shaft, so that when the input shaft rotates in the reverse direction, the dead time of the output shaft in the reverse rotation of the input shaft can be calculated by synchronously acquiring the first curve waveform of the angle and the time of the input shaft and the second curve waveform of the angle and the time of the output shaft, the angle change of the input shaft can be calculated in the dead time, and the backlash between the first gear and the second gear can be accurately calculated by means of the angle change, therefore, the measurement accuracy of the backlash is improved, and meanwhile, because the size of the backlash has a certain proportional relation with the current to be output by the driving end driving the input shaft, when the backlash is adjusted, a current curve output by the driving end when the input shaft rotates forwards or reversely at a constant speed can be intercepted, the average value of the current output by the driving end can be calculated through the curve, and the axial position of the first gear relative to the second gear can be effectively adjusted by means of the relation between the average value of the current and the measured backlash.

In addition, in the step of calculating the stagnation time period Δ t of the output shaft when the input shaft rotates in the reverse direction, the method specifically includes:

recording a starting time point t1 of the input shaft when rotating in the reverse direction;

recording a starting time point t2 of the output shaft when rotating in the reverse direction;

calculating a difference between the t1 and the t2, and taking the difference as a stagnation time period at of the output shaft when the input shaft rotates in the reverse direction.

In addition, the step of calculating the angle change value Δ θ of the input shaft within the dead time period Δ t specifically includes:

acquiring a rotation angle theta 1 of the input shaft at the initial time point of the stagnation time delta t;

acquiring a rotation angle theta 2 of the input shaft when the stagnation time delta t is finished;

and calculating an angle difference value between the theta 1 and the theta 2, and taking the angle difference value as an angle change value delta theta of the input shaft.

In addition, the step of measuring a backlash between a first gear connected to the input shaft and a second gear connected to the output shaft based on the calculated angle change value Δ θ of the input shaft specifically includes:

calculating a reduction ratio i between the input shaft and the output shaft when the output shaft rotates in a reverse direction;

substituting the calculated reduction ratio i into a formula: the backlash is measured as the reduction ratio i × the angle change value Δ θ.

In addition, the step of judging whether the current average value and the measured backlash satisfy a preset condition specifically comprises the following steps;

if the calculated current average value is larger than a preset current value or the measured backlash is larger than a preset backlash, judging that the current average value and the measured backlash do not meet a preset condition;

and if the calculated current average value is not greater than a preset current value and the measured backlash is not greater than a preset backlash, judging that the current average value and the measured backlash meet a preset condition.

In addition, the step of adjusting the axial position of the first gear connected to the input shaft relative to the second gear specifically includes;

if the calculated current average value is not greater than a preset current value, but the measured backlash is greater than a preset backlash, controlling the first gear to move towards the direction of the second gear;

and if the calculated current average value is larger than a preset current value and the measured backlash is not larger than the preset backlash, controlling the first gear to move towards the direction far away from the second gear.

In addition, when the input shaft rotates at a constant speed, the current value output by the drive end increases as the backlash becomes smaller.

Drawings

Fig. 1 is a schematic view of a robot to which a backlash measuring method according to a first embodiment of the present invention is applied;

fig. 2 is a schematic flow chart of a backlash measuring method according to a first embodiment of the present invention;

FIG. 3 is a waveform of the angle versus time curves of the input and output shafts as they rotate in accordance with the first embodiment of the present invention;

FIG. 4 is a schematic flow chart of a backlash adjustment method according to a second embodiment of the present invention;

fig. 5 is a schematic view of a backlash measuring apparatus according to a third embodiment of the present invention applied to a robot;

fig. 6 is a system block diagram of a backlash measuring apparatus according to a third embodiment of the present invention;

fig. 7 is a system block diagram of a backlash adjustment mechanism according to a fourth embodiment of the present invention;

fig. 8 is a schematic view of a backlash adjustment device according to a fourth embodiment of the present invention applied to a robot.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in order to provide a better understanding of the present application in various embodiments of the present invention. However, the technical solutions claimed in the claims of the present application can be implemented without these technical details and with various changes and modifications based on the following embodiments.

The first embodiment of the present invention relates to a backlash measuring method which can be used for a robot shown in fig. 1, for example, but can be used for other precision transmission mechanisms. As can be seen from fig. 1, the first transmission gear 5 is provided in the robot arm 11 of the robot and the second transmission gear 6 is provided in the robot arm 10 of the robot, while the first transmission gear 5 is connected to the input shaft 1 and the second transmission gear 6 is connected to the output shaft 2, and the first transmission gear 5 and the second transmission gear 6 are engaged with each other. Thus, after the input shaft 1 drives the first gear 5 to rotate, the second gear 6 can rotate together with the first gear 5 by means of the engagement with the first gear 5 while the first gear 5 rotates, thereby driving the output shaft 2 to rotate, so that the end flange connected with the output shaft 2 can rotate along with it. Since the backlash is generated when the first gear 5 and the second gear 6 are engaged, when the input shaft 1 drives the first gear 5 to rotate in the forward direction and then the input shaft 1 drives the first gear 5 to rotate in the reverse direction, because of the backlash existing between the first gear 5 and the second gear 6, the output shaft 2 will have a very short stagnation phenomenon at the initial stage of the reverse rotation of the input shaft 1, and the stagnation phenomenon will have a certain influence on the movement precision of the subsequent end flange, so that in the process of controlling the movement of the robot arm, it is usually necessary to compensate the control according to the measured backlash, and therefore it becomes important how to accurately measure the backlash between the first gear 5 and the second gear 6, and the backlash measurement method of the present embodiment can just solve the problem of measuring the backlash, as shown in fig. 2, the backlash measuring method of the present embodiment may specifically include the steps of:

step 210, driving the input shaft 1 to rotate in the forward direction.

Step 220, at a certain moment, the input shaft 2 is driven to rotate reversely, and a first curve waveform of the angle and the time of the input shaft 2 and a second curve waveform of the angle and the time of the output shaft 2 are synchronously acquired.

And step 230, calculating the stagnation time duration delta t of the output shaft 2 when the input shaft 1 rotates reversely according to the obtained first curve waveform and the second curve waveform.

And 240, calculating an angle change value delta theta of the input shaft 1 in the stagnation time period delta t according to the calculated stagnation time period delta t.

And step 250, measuring the backlash between the first gear 5 connected with the input shaft 1 and the second gear 6 connected with the output shaft 2 according to the calculated angle change value delta theta of the input shaft.

It is obvious from the above description that, in the backlash measuring method of the present embodiment, by means of the characteristics of the backlash itself, the input shaft 1 is driven to drive the first gear 5 to rotate in the reverse direction at a certain time in the process of driving the input shaft 1 to drive the first gear 5 to rotate in the forward direction, and at the initial stage of the reverse rotation of the input shaft 1, the output shaft 2 is stopped for a very short time due to the backlash generated between the output shaft 2 and the input shaft 1, so that when the input shaft 1 rotates in the reverse direction, the time period of stopping the output shaft 2 when the input shaft 1 rotates in the reverse direction can be calculated by synchronously acquiring the first curve waveform of the angle and the time of the input shaft 1 and the second curve waveform of the angle and the time of the output shaft 2, and the change of the angle of the input shaft can be calculated in the time period, and the backlash between the first gear 5 and the second gear 6 can be accurately calculated by means of the change of the angle, thereby improving the measurement accuracy of backlash.

It should be noted that, in practical application, as shown in fig. 1, the input shaft 1 may be connected to a main shaft of the servo motor 4 through a coupling 3, so that the servo motor 4 may serve as a driving end for driving the input shaft 1 to rotate in the present embodiment, and meanwhile, the driving end may be externally connected to a main control module, so that the driving end may drive the input shaft 1 to rotate in a forward direction or a reverse direction under the control of the main control module. In addition, in order to realize the collection of the angle and time curve waveforms of the input shaft 1 and the output shaft 2 during rotation, as shown in fig. 1, the servo motor 4 is a servo motor with a coder, a coder 7 connected with the output shaft 2 is arranged on the mechanical arm 10, a first curve waveform a of the angle and time of the input shaft and a second curve waveform b of the angle and time of the output shaft 2 can be synchronously collected when the input shaft 1 is driven to rotate reversely by the driving end through the two coders respectively, and then the main control module is used for calculating the stagnation time duration Δ t of the output shaft 2 during reverse rotation of the input shaft 1 according to the first curve waveform a and the second curve waveform b, as shown in fig. 3. And after the main control module calculates the stagnation time delta t, the main control module can calculate the angle change value delta theta of the input shaft 1 within the stagnation time delta t, and accurately measure the backlash between the first gear 5 and the second gear 6 according to the angle change value delta theta of the input shaft 1.

Specifically, the step 230, as shown in fig. 3, specifically includes:

a start time t1 of the input shaft 1 at the time of the reverse rotation is recorded on the first curve waveform a.

The start time t2 of the output shaft 2 in the reverse rotation is recorded on the second curve waveform b.

The difference between t1 and t2 is calculated and taken as the stagnation period Δ t of the output shaft at the time of reverse rotation of the input shaft.

In addition, it should be noted that the step 240 specifically includes:

the rotation angle θ 1 of the input shaft at the start time point of the dead time period Δ t is acquired on the first curve waveform a.

The rotation angle θ 2 of the input shaft at the time point when the dead time period Δ t ends is acquired on the second curve waveform b.

An angle difference between θ 1 and θ 2 is calculated, and the angle difference is taken as an angle change value Δ θ of the input shaft.

In the present embodiment, the start time point t1, the start time point t2, the rotation angle θ 1, and the rotation angle θ 2 are all recorded and obtained by the main control module on the first curve waveform a and the second curve waveform b, as shown in fig. 3.

In addition, the step 250 specifically includes:

the reduction ratio i between the input shaft 1 and the output shaft 2 when the output shaft 2 rotates in the reverse direction is calculated.

Substituting the calculated reduction ratio i into a formula: the backlash between the first gear 5 and the second gear 6 is measured as the reduction ratio i × the angle change value Δ θ.

In the present embodiment, the reduction ratio i and the backlash can be calculated by the main control module.

A second embodiment of the present invention relates to a backlash adjustment method, as shown in fig. 4, including the steps of:

in step 410, the backlash measured by the backlash measurement method according to the first embodiment is acquired.

And step 420, intercepting a current output curve of the driving end in a certain time period when the input shaft 1 rotates at a constant speed in the forward direction or the reverse direction.

In step 430, the current average value in the current output curve is calculated.

Step 440, determining whether the current average value and the measured backlash satisfy a predetermined condition.

And 450, if the preset condition is judged not to be met, adjusting the axial position of the first gear 5 connected with the input shaft relative to the second gear 6, returning to the step 310 after the axial position of the first gear is adjusted, and continuing to execute the steps.

And step 460, finishing backlash adjustment if the preset condition is not met.

In combination with the above-mentioned adjustment method, it is obvious that since the size of the backlash between the first gear 5 and the second gear 6 has a certain relationship with the size of the current output by the servo motor 4, i.e. the output end, that is, the smaller the backlash between the first gear 5 and the second gear 6, the tighter the first gear 5 and the second gear 6 are engaged with each other is indicated, so that the driving end needs to provide a larger torque, i.e. needs to output a larger current, when in operation. Conversely, the larger the backlash between the first and second gears 5, 6, the less torque the drive end needs to provide in operation and therefore the relatively small current output. Therefore, when the input shaft 1 rotates at a constant speed, the current value output by the driving end increases along with the reduction of the backlash, so that the size of the backlash between the first gear 5 and the second gear 6 and the current to be output by the driving end driving the input shaft 1 have a certain proportional relation, when the backlash is adjusted, a current output curve of the input shaft 1 rotating at the constant speed in the forward direction or the reverse direction can be intercepted, the average value of the current output by the driving end can be calculated through the curve, and whether the backlash between the first gear 5 and the second gear 6 meets the preset condition can be judged by means of the relation between the average value of the current and the measured backlash, so that a worker can effectively adjust the axial position of the first gear 5 relative to the second gear 6.

Specifically, in step 440, the step of determining whether the calculated average current value and the measured backlash satisfy the preset condition specifically includes:

if the calculated current average value is larger than the preset current value or the measured backlash is larger than the preset backlash, the current average value and the measured backlash are judged not to meet the preset condition, and at the moment, the axial position of the first gear relative to the second gear needs to be adjusted.

If the calculated current average value is not greater than the preset current value and the measured backlash is not greater than the preset backlash, the current average value and the measured backlash are judged to meet the preset condition, and at the moment, the axial position of the first gear relative to the second gear does not need to be adjusted.

In addition, in order to accurately adjust the first gear after determining that the calculated current average value and the measured backlash do not satisfy the preset condition, step 450 specifically includes;

if the calculated average value of the current is not greater than the preset current value, but the measured backlash is greater than the preset backlash, it indicates that the backlash between the first gear 5 and the second gear 6 is too large, and therefore, it is necessary to control the first gear 5 to move toward the second gear 6 to reduce the backlash between the first gear 5 and the second gear 6.

If the calculated average value of the current is larger than the preset current value but the measured backlash is not larger than the preset backlash, it indicates that the backlash between the first gear 5 and the second gear 6 is too small, and therefore, it is necessary to control the first gear 5 to move away from the second gear 6 to increase the backlash between the first gear 5 and the second gear 6.

Therefore, it is not difficult to find that the backlash between the first gear 5 and the second gear 6 can be accurately adjusted by the backlash adjusting method, and the phenomena of vibration and noise generated during the meshing transmission of the first gear 5 and the second gear 6 can be avoided while the accuracy during the meshing transmission of the first gear 5 and the second gear 6 is improved.

A third embodiment of the present invention relates to a backlash measuring apparatus, as shown in fig. 5, including: the device comprises a driving end, a first detection module, a second detection module and a main control module.

As shown in fig. 5, the driving end is a servo motor 4, the servo motor 4 is fixed on the mechanical arm 11 through a motor bracket 8, and a main shaft of the servo motor 4 is connected with the input shaft 1 through a coupling 3, so that the servo motor 4 can be used for driving the input shaft 1 to rotate in the forward direction or the reverse direction. Meanwhile, the first detection module is used for synchronously detecting the rotation angle of the input shaft 1 and outputting a first curve waveform of the angle and the time of the input shaft 1 when the servo motor 4 drives the input shaft 1 to rotate, and the second detection module is used for synchronously detecting the rotation angle of the output shaft 2 and outputting a second curve waveform of the angle and the time of the output shaft 2 when the servo motor 4 drives the input shaft 1 to rotate.

In addition, as shown in fig. 6, the main control module is in communication connection with the first detection module and the second detection module, respectively. Therefore, in practical application, the servo motor 4 can be made to drive the input shaft 1 to rotate in the forward direction, and the servo motor 4 can be made to drive the input shaft 1 to rotate in the reverse direction at a certain moment, when the input shaft 1 rotates in the reverse direction, the first detection module can be used for synchronously detecting the rotation angle of the input shaft 1 and outputting a first curve waveform of the angle and the time of the input shaft 1 to the main control module, and the second detection module can be used for synchronously detecting the rotation angle of the output shaft 2 and outputting a second curve waveform of the angle and the time of the output shaft 2 to the main control module. The main control module can calculate the stagnation time delta t of the output shaft 2 when the input shaft 1 rotates reversely according to the first curve waveform and the second curve waveform. And after the stagnation period deltat is obtained, an angle change value deltatheta of the input shaft 1 is calculated within the stagnation period deltat, and simultaneously, according to the angle change value deltatheta, a backlash between a first gear 5 connected with the input shaft 1 and a second gear 6 connected with the output shaft 2 is measured.

Specifically, in the present embodiment, as shown in fig. 5, the first detection module is an encoder (not shown) provided in the servo motor 4, and the second detection module is an encoder 7 connected to the output shaft 2, the encoder 7 may be fixed to the robot arm 10 by an encoder bracket 9, and the two encoders may be used to accurately detect the rotation angles of the input shaft 1 and the output shaft 2.

As is apparent from the contents of the present embodiment, the present embodiment is an apparatus example corresponding to the first embodiment, and the present embodiment can be implemented in cooperation with the first embodiment. The related technical details mentioned in the first embodiment are still valid in this embodiment, and are not described herein again in order to reduce repetition. Accordingly, the related-art details mentioned in the present embodiment can also be applied to the first embodiment.

A fourth embodiment of the present invention relates to a backlash measuring apparatus, as shown in fig. 7, including: the device comprises a current detection module (not marked in the figure), a main control module and a backlash adjusting mechanism.

The current detection module is in communication connection with the main control module and is used for detecting a current value output by the driving end, namely the servo motor 4, when the input shaft 1 rotates in the forward direction or the reverse direction. The main control module is used for continuously acquiring the current values detected by the current detection module and automatically generating relevant curve waveforms according to the acquired current values.

In the practical application process, the main control module may intercept a section of the curve waveform of the input shaft 1 during uniform rotation on the curve waveform as an output current curve of the servo motor 4, and calculate the average value of the current output by the servo motor 4 in the section of time according to the current output curve. In addition, the main control module is further configured to determine whether the average value of the current output by the servo motor 4 during the period of time and the backlash obtained by using the backlash measurement device according to the third embodiment satisfy a preset condition, and after it is determined that the preset condition is not satisfied, the backlash adjustment mechanism may change the axial position of the first gear 5 relative to the second gear 6, thereby achieving the effect of adjusting the backlash.

Specifically, in the present embodiment, as shown in fig. 8, the backlash adjustment mechanism is a sleeve 12 sleeved outside the shaft side 51 of the first gear 5, the sleeve 12 is fixed relative to the shaft side 51 of the first gear 5 in the axial direction, so that the axial position of the first gear 5 can be adjusted by the axial displacement of the sleeve 12, and the sleeve 12 is rotationally engaged with the shaft side 51 of the first gear 5 through two pairs of bearings 13 in the radial direction, so that the sleeve 12 can not affect the normal rotation of the first gear 5 through the two pairs of bearings 13. Meanwhile, in order to realize the axial displacement of the shaft sleeve 12, a thread screwing mode can be adopted between the shaft sleeve 12 and the shell of the mechanical arm 11, so that when the main control module judges that the average value of the current output by the servo motor 4 in the corresponding time period and the backlash obtained by the backlash measuring device adopting the third embodiment do not meet the preset condition, the shaft sleeve 12 can be rotated to drive the first gear 5 to realize the axial position adjustment by means of the thread screwing relation between the shaft sleeve 12 and the shell of the mechanical arm 11 by rotating the shaft sleeve 12. It should be noted that, in the present embodiment, the rotation of the shaft sleeve 12 may be manually driven by an external tool to rotate, or an additional set of driving device for driving the shaft sleeve 12 to rotate may be added to realize the automatic rotation of the shaft sleeve 12, but in the present embodiment, the rotation mode of the shaft sleeve 12 is not specifically limited.

As is apparent from the contents of the present embodiment, the present embodiment is an example of an apparatus corresponding to the second embodiment, and the present embodiment can be implemented in cooperation with the second embodiment. The related technical details mentioned in the second embodiment are still valid in this embodiment, and are not described herein again in order to reduce repetition. Accordingly, the related-art details mentioned in the present embodiment can also be applied to the first embodiment.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.