JPH07102405B2 - Bending correction method for parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention <Field of Industrial Application> The present invention relates to a method for correcting bending of a member.

<Prior Art> For example, in a power window motor for an automobile, a worm formed on a driving end portion of a rotor shaft and a worm wheel integrally formed with an output shaft connected to open and close the window are meshed with each other. By doing so, a small motor may obtain a large output to open and close the window. In this worm gear coupling, in order to perform stable and efficient gear transmission, it is necessary to use a worm with as little bending as possible, that is, center deviation. Therefore, after forming the worm on the rotor shaft, the core runout of the worm is measured by the core runout measuring device, and if the measured value is outside the allowable value, the worm is corrected.

In the conventional runout correction method, the runout of the worm is corrected with a correction value obtained by multiplying the runout measurement value by a predetermined coefficient. In addition, there may be a difference in shape, and there is a possibility that the same correction value as that of the previous lot cannot be obtained with the same correction value as that of the previous lot. Therefore, every time the lot is changed, the above-mentioned coefficient is changed again by the worker, which causes a problem that the center runout correction work becomes complicated.

<Problems to be Solved by the Invention> In view of such problems of the conventional technology, a main object of the present invention is to bend a member capable of automatically correcting a difference in correction value caused by changing a production lot. To provide a correction method.

[Structure of the Invention] <Means for Solving the Problem> According to the present invention, such an object is corrected by deforming a member having a bending in one direction in a direction opposite to the bending direction. A method for correcting the bending of a member of the type, the step of measuring the bending amount of the member, the step of correcting the member based on a table that gives the correction amounts according to a plurality of specific bending amount ranges, and The step of measuring the amount of bending of the member and comparing with the allowable value, and if the amount of bending of the member after the correction is outside the allowable value, the portion of the table corresponding to the amount of correction in the correction process is A method for correcting the bending of a member is provided, further comprising the step of correcting by gradually adding a feedback value that gradually decreases and becomes a predetermined value in response to an increase in the number of times of correction to obtain the data of the relevant portion. Do It is achieved by the.

<Operation> In this way, even when the material and shape of the member are changed due to the change of the production lot and the correct amount cannot be corrected with the correction amount in the previous lot for the same bending amount, Since the correction amount in the correction process is corrected and correction is performed again, the optimum correction amount in a new lot can be automatically calculated.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram schematically showing an outline of an apparatus 2 for correcting core runout of a rotor shaft 1 to which the present invention is applied. For example, a worm wheel 1a is formed in the output end portion on the right side of the rotor shaft 1 used in an automobile power window motor in the figure, and a worm wheel in a gear box integrally assembled with the power window motor. And the worm 1a mesh with each other. This warm
When the 1a is bent, that is, when the center runout is generated, stable and efficient gear transmission cannot be performed. Therefore, in the motor manufacturing process, after the worm 1a is formed on the rotor shaft 1, the center runout correction device 2 performs the center runout. Is measured, and if it is out of the allowable value, it is corrected.

The center runout correction device 2 is provided with a displacement sensor 3 for measuring the runout of the worm 1a, and a pulse motor 4 with a lead screw as an actuator for correcting the runout. The displacement sensor 3 is composed of, for example, a direct-acting displacement sensor, and has a slide shaft 3a that is elastically urged inward in the radial direction of the rotor shaft 1 and is reciprocally movable.
Abutting piece 3b swingably provided on the protruding end of the slide shaft 3a
By measuring the center runout of the worm 1a by bringing the abutment piece 3b into contact with the outer peripheral surface of the worm 1a over a plurality of teeth so as not to be affected by the lack of teeth of the worm 1a. , And outputs the measured value to the control device 5. Also,
When the pulse motor 4 pushes down the tip end of the rotor shaft 1 on the worm 1a side by the protruding end of the drive shaft 4a in the direction of arrow A in the figure, which is the direction to correct the bending of the worm 1a, The drive signal causes rotation by the number of pulses corresponding to a correction value described later.

Next, the operation procedure of the core shake correction device 2 thus configured will be described below with reference to the flowchart shown in FIG.

First, in step ST1, the contact piece 3b of the displacement sensor 3 is attached to the rotor shaft 1 which is gripped by a chuck (not shown) and is in a fixed state as described above.
The rotor shaft 1 is rotated once around the true axis by rotating the chuck, for example, while elastically contacting the outer peripheral surface of the worm 1a, and the runout of the worm 1a is measured. At this time, the measured value of half the swing width in the vertical direction of the worm 1a rotated once is stored as the position of the true shaft center so that the displacement sensor 3 is moved from the position of the true shaft center in the figure.
By subtracting the displacement amount measured by, the center runout amount Y in which the upper side of the true axis has a positive value and the lower side has a negative value can be calculated. Furthermore, the rotor shaft 1
Rotate and position at the position where the positive value of runout becomes maximum.

Next, in step ST2, the preset allowable value is compared with the core runout amount measured in step ST1, and if the core runout amount is within the allowable value, the process ends without correction, and If the amount of runout is outside the allowable value, the process proceeds to step ST3, and the runout is corrected in step ST3. When correcting this runout, in order to push the drive shaft 4a and push down the tip end portion of the rotor shaft 1 as described above, the pulse motor 4 is adjusted to a correction amount in a memory unit 6 described later. Rotate only the pulse corresponding to the data Z. The correction amount data Z is read from a so-called data table provided according to a plurality of specific range of center deviation amounts. Then, in step ST4, the amount of runout after correction is measured, and in the next step ST5, the allowable amount of runout is compared again with the amount of runout measured in step ST4, and the amount of runout is calculated. If it is within the allowable value, the process ends without correction.

In step ST5, when the center runout amount is out of the allowable value, the process proceeds to step ST6. The reason why the process proceeds to step ST6 is that the correction based on the stocked correction amount data Z was insufficient. Therefore, in step ST6, the feedback value for correcting the correction amount data Z is used. Xn is calculated by the following formula.

Xn = A · Y / (n + 3) A in the above equation is the number of pulses per unit runout amount for rotating the pulse motor 4, and n is the step ST3.
Is a value that is incremented when there is something that has not been sufficiently corrected in step ST6 and has proceeded to step ST6 (the number of rotor shafts for which the same amount of runout has been measured). Step ST
At 1, for example, a certain amount of runout (Y = Y1) is measured for the first time,
The correction based on the correction amount data corresponding to the center runout amount Y1 is performed in step ST3, and if the process does not fall within the allowable value and proceeds to step ST6, the correction formula in the correction formula corresponding to the above center runout amount Y1 Let n be 1. Then, similarly for other rotor shafts, different core run-out amounts Y2, Y3, ... When the process proceeds to step ST6, similarly, then step ST1
When the center runout amount Y1 is measured at step ST6 and the process proceeds to step ST6, the number of corrections to the center runout amount Y1 becomes the second time, and n when performing the correction by the above equation is set to 2. Therefore, when the process proceeds to step ST6 for the first time, the correction formula n corresponding to the table portion of the center runout amount (eg, Y1) measured at step ST1 at that time becomes 1 and the feedback value X _n is obtained. The denominator of the above equation is 4, and as the number of steps that proceed to step ST6 at the same center runout amount (Y1) increases, n in the correction equation increases by one, so the value of Xn gradually converges. . The upper limit value of n may be set to, for example, about 15, and the feedback value is gradually reduced to a predetermined value as the number of corrections increases.

Further, in the control device 5, the correction amount data Z is calculated by the following equation.

Z = A · Y + ΣXn That is, the number of pulses for rotating the pulse motor 4 proportional to the center runout amount Y is calculated by the first term on the right side of the above equation, and the cumulative feedback value Xn is calculated by the second term. The value is calculated, and the correction amount data Z is calculated by the sum of the two. The correction amount data Z is stocked in the data table divided into a plurality of specific runout amount ranges as described above, and the feedback value X is calculated in step ST6.
After n is calculated, the correction amount data Z stored in the section of the base runout amount Y which is the basis is rewritten.

Then, for those returned to step ST3, the pulse motor 4 is rotated by a corresponding number of pulses with the correction amount data Z corresponding to the center runout amount Y measured in step ST4, and the correction is performed again.

In step ST1 of the next new rotor shaft 1, if the same amount of runout Y as the runout in which the corrective runout data Z is corrected before that is measured, the data Z of the straightening amount applied to itself is obtained. , The feedback value Xn has been increased from the previous value, and a larger correction can be performed. However, if the correction amount data Z is still insufficient, the process proceeds to step ST6, and the correction amount data Z is corrected again. It should be noted that the feedback value Xn included in the correction amount data Z decreases as the number of corrections by measuring the same center runout amount Y as described above increases, and a predetermined value is obtained by setting the upper limit value of n. Therefore, since the correction amount data Z also converges,
It is possible to suitably prevent the inconvenience that the correction width for the correction amount data Z is too large, and it is possible to automatically obtain the appropriate correction amount data Z.

By the way, in step ST6, after the feedback value Xn is calculated as described above, the process proceeds to step ST7, and in step ST7, when it is detected that N times the test is failed in step ST5, Then, the process proceeds to step ST8, displays the failure and ends, and when the failure is less than N times, returns to step ST3 and corrects again. This step ST7
In the case of producing a motor on an automatic production line, for example, the number of confirmations is preferably twice.

In step ST6 of this embodiment, the feed hack value X
As the denominator of the equation for calculating n, 3 was added to the number of the same runout amount Y, but it is not limited to n + 3, and the numerical value to be added to n may be changed depending on the shape and material of the rotor shaft 1. It can be changed appropriately. Further, in the present embodiment, the worm is formed on the rotor shaft of the motor, but the present invention is not limited to the shaft. For example, a part of the plate member used in a straight state is bent to cause bending. It can also be applied to the ones.

Further, in the present embodiment, the worm 1a is used as the displacement sensor 3.
The contact piece 3b that abuts the outer peripheral surface of was used. However, if a worm wheel that meshes with the worm 1a is used instead of the contact piece 3, the portion that actually needs to be centered is directly measured, Higher precision correction can be performed.

[Effects of the Invention] As described above, according to the present invention, when the amount of bending of a member corrected based on a certain amount of correction is outside the allowable value, the amount of correction is corrected so that the same amount of bending is corrected again. When performing correction on a member with a certain amount of correction, the correction amount is corrected and the optimum correction value can be automatically obtained, and the correction amount is set each time the lot is changed. Since there is no need for the person to change it, the effect of improving the efficiency of the work for correcting the bend can be extremely large.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an outline of a bending correction apparatus for a member to which the present invention is applied. FIG. 2 is a flowchart showing the operating procedure of the correction device. 1 ... Rotor shaft, 1a ... Worm 2 ... Core runout correction device, 3 ... Displacement sensor 3a ... Slide shaft, 3b ... Abutting piece 4 ... Pulse motor, 4a ... Drive shaft 5 ... Control Device, 6 ... Memory part

Claims (1)

[Claims] 1. A bending correction method for a member of a type in which a member having a bending in one direction is deformed in a direction opposite to the bending direction to correct the member, and a step of measuring a bending amount of the member, , A step of correcting the member based on a table which gives a correction amount in accordance with each of a plurality of specific bending amount ranges, a process of measuring the bending amount of the member after correction and comparing it with an allowable value, and When the bending amount of the member is out of the allowable value, the portion of the table corresponding to the correction amount in the correction process is gradually reduced in accordance with the increase in the number of corrections so as to be the data of the portion thereafter. And a step of correcting by adding a feedback value that becomes a predetermined value.