JP4371401B2 - Method and apparatus for adjusting pitch of coil spring forming machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pitch adjusting method and apparatus for a coil spring forming machine, and more particularly to a pitch adjusting method and apparatus for a coil spring forming machine suitable for manufacturing a coil spring having a multi-stage pitch or an unequal pitch.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a coil spring molding machine that sets NC data based on a plurality of parameters that specify a coil spring having a desired shape and forms the coil spring based on the NC data is known. On the other hand, it is required to adjust the pitch according to the characteristics of the coil spring. However, non-linear spring characteristics such as a non-uniform pitch coil spring S1 shown in FIG. 9 and a multi-stage pitch (symmetric two-stage pitch) coil spring S2 shown in FIG. 10, such as a coil spring used for a valve spring for an automobile engine. In the case of forming a coil spring having the above, it is extremely difficult to ensure the pitch accuracy that satisfies the required characteristics only by setting the conditions directly with respect to the conventional pitch tool, which will be described in detail later.
[0003]
By the way, in the following Patent Document 1, in an automatic programming device for a coil spring molding machine, the NC program generated by replacing the G code of the NC program, adding the M code, etc. is immediately corrected without modification. For the purpose of enabling the spring forming operation, it has been proposed to set in advance the correction contents to be applied to the NC program as auxiliary operation data. Specifically, auxiliary operation data representing the correction contents of the NC program is set in advance in the automatic programming device for the coil spring molding machine, and the operator checks the auxiliary operation data displayed on the CRT, and correction is necessary. If so, it will be input again. For example, ten pieces of auxiliary operation data are prepared, and data numbers are assigned to the auxiliary operation data. This describes that the molding preparation time until the operator obtains the desired NC program can be shortened.
[0004]
[Patent Document 1]
[Patent Document 1] Japanese Patent Laid-Open No. 8-168841
[Problems to be solved by the invention]
The unequal pitch coil spring S1 in FIG. 9 and the multi-stage pitch coil spring S2 in FIG. 10 have different pitches depending on the number of turns as shown in FIG. For coil springs that presuppose line-to-line contact in the first half of such an operating range, even if the pitch adjustment method in a normal coil coil of equal pitch is applied, it cannot be adjusted to a desired pitch. It is difficult to ensure accuracy during mass production. For example, when coil springs such as those shown in FIGS. 9 and 10 are sequentially formed from the end by ordinary cold coil forming, if the pitch value at the beginning of winding is inaccurate, an error will occur until the winding end. Since they are accumulated, the deviation from the target value in the load deflection characteristic becomes large. This is different from the method of determining the overall shape at once by inserting material into the overall mold. For this reason, the location of the small pitch has a great influence on the initial load characteristics, and the accuracy of the initial small pitch portion greatly affects not only the initial load characteristics but also the entire load characteristics including the latter half.
[0006]
Therefore, when forming coil springs with unequal pitches or multi-step pitches, the product load characteristic allowable value cannot be satisfied unless the pitch accuracy at the beginning of winding can be accurately controlled. Further, when shifting from the winding start portion to another portion, it is necessary to quickly switch the pitch sequentially each time. For this reason, it is necessary to obtain a setup value that can accurately respond to a plurality of pitch values according to various spring specifications, and to set an appropriate relationship between the target value and the setup value.
[0007]
However, in the automatic programming device for a coil spring forming machine described in Patent Document 1, the auxiliary operation data to be corrected is selected from, for example, 10 auxiliary operation data prepared in advance and converted into an NC program. Therefore, it is essential to set in advance the correction contents to be applied to the NC program as auxiliary operation data. In addition, regarding the setting of the auxiliary operation data, there is no mention of the relationship with the operating state of the coil spring molding machine, and of course there is no suggestion for solving the problem in the pitch adjustment method described above.
[0008]
Therefore, the present invention provides a highly accurate pitch according to the characteristics of a coil spring forming machine that forms coil springs based on NC data, even when forming coil springs of unequal pitch or multi-step pitch. It is another object of the present invention to provide a pitch adjustment method that can be adjusted quickly.
[0009]
Further, the present invention provides a coil spring capable of adjusting the pitch with high accuracy and speed according to the characteristics even when the coil spring is formed with an unequal pitch or a multi-stage pitch with respect to the coil spring forming machine. Another object is to provide a pitch adjusting device for a molding machine.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, according to the present invention, NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil is set based on the NC data. In the coil spring forming machine for adjusting the pitch of the coil spring according to the characteristics of the coil spring, the pitch indication value is (X) and the pitch target value is ( Y), the proportionality coefficient is (B), the lag component is (A), Y = B · X + A is set to a predetermined proportional relationship represented by a linear equation and used as basic NC data, and the coil spring forming is based on the basic NC data pitch measured value when driving the machine to molding the coil spring as compared with the pitch target value (Y), the deviation between the pitch measured value and the pitch target value (Y) Hazuki sets a first adjustment parameter to match with the pitch measured value and the pitch instruction value (X) a delay component of the predetermined proportionality delay component for proportional relationship (A) (α), the pitch A second adjustment parameter (β) for setting the proportionality coefficient in the proportional relationship between the actually measured value and the pitch instruction value (X) to coincide with the proportionality coefficient (B) in the predetermined proportionality relationship is set, and the first adjustment parameter ( with adjusting the operation start position of the pitch tool based on alpha), by adjusting the ratio of the amount of movement of said pitch tool with respect to the pitch indicated value on the basis of the second adjustment parameter (β) (X), the coil The pitch of the spring is adjusted.
[0011]
Thus, when the pitch instruction value is X and the pitch target value is Y, the proportional relationship between the pitch instruction value and the pitch target value can be expressed by a linear expression of Y = B · X + A. The proportionality coefficient (B) and the delay component (A) in the equation are set as target values. Further, the measured pitch value is measured at at least two points spaced apart in the axial direction in the coil spring, so that a linear expression representing a proportional relationship between the measured pitch value and the pitch indication value can be set.
[0012]
Alternatively, according to the present invention, as described in claim 2, a coil that sets NC data based on a plurality of parameters including at least a pitch parameter that specifies a desired coil spring, and forms the coil spring based on the NC data. In a pitch adjusting method for a coil spring forming machine that adjusts the pitch of the coil spring according to the characteristics of the coil spring, the pitch indication value is (X), the pitch target value is (Y), and the proportional coefficient. (B), delay component (A) and Y = B · X + A set to a predetermined proportional relationship represented by a linear equation to obtain basic NC data, and the coil spring molding machine is driven based on the basic NC data. comparing the pitch measured values at the shaping of the coil spring the pitch target value (Y), based on the deviation between the pitch measured value and the pitch target value (Y), said pin Chi actual measurement value and the pitch indicated value proportional relationship between (X) and re-set the basic NC data so as to coincide with the predetermined proportional relationship to a reset NC data, based on該再setting NC data, the It is good also as adjusting the pitch of a coil spring.
[0013]
According to a third aspect of the present invention, the NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil spring is formed based on the NC data. In the coil spring forming machine for adjusting the pitch of the coil spring according to the characteristics of the coil spring, the pitch instruction value is (X), the pitch target value is (Y), The proportional coefficient is set to (B), the delay component is set to (A), and a predetermined proportional relationship expressed by a linear equation of Y = B · X + A is set as basic NC data, and the coil spring molding machine is driven based on the basic NC data. and a pitch detecting means for detecting the pitch measured values at the shaping of the coil spring, the pitch measured values said pitch detecting means detects the pitch target value (Y) comparison , Based on the deviation between the pitch measured value and the pitch target value (Y), the pitch measured value and the pitch instruction value and delay component (A) of the predetermined proportionality delay component to proportional relation (X) A first adjustment parameter (α) to be matched is set, and a proportional coefficient in the proportional relationship between the actually measured pitch value and the pitch instruction value (X ) is matched with the proportional coefficient (B) of the predetermined proportional relationship. Adjustment parameter setting means for setting the adjustment parameter (β) , and adjusting the operation start position of the pitch tool based on the first adjustment parameter (α) set by the adjustment parameter setting means, and the second adjustment parameters by adjusting the proportion of the amount of movement of said pitch tool with respect to the pitch indicated value on the basis of the (β) (X), the pitch adjustment means for adjusting the pitch of the coil spring It is to be prepared.
[0014]
Alternatively, as described in claim 4, in a coil spring molding machine that sets NC data based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and forms the coil spring based on the NC data. On the other hand, in the pitch adjustment device of the coil spring molding machine that adjusts the pitch of the coil spring according to the characteristics of the coil spring, the pitch instruction value is (X), the pitch target value is (Y), and the proportionality coefficient is (B). , The delay component is (A) and set to a predetermined proportional relationship represented by a linear equation of Y = B · X + A to obtain basic NC data. Based on the basic NC data, the coil spring molding machine is driven to comparing the pitch detecting means for detecting the pitch measured value at the time of molding, the pitch measured values said pitch detecting means detects the pitch target value (Y), the pitch Based on the deviation between the measured value and the pitch target value (Y), re-set the basic NC data the pitch measured value and the pitch indicated value proportional relationship between (X) so as to coincide with the predetermined proportional relationship Then, resetting means for setting resetting NC data and pitch adjusting means for adjusting the pitch of the coil spring based on the resetting NC data set by the resetting means may be provided.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, and a plurality of parameters 11 such as a coil diameter, the number of turns, and a pitch for specifying a desired coil spring are input to the NC controller 10. The NC controller 10 is configured such that NC data is set based on the plurality of parameters, the coil spring forming machine 20 is driven and controlled based on the NC data, and the coil spring 1 is formed. In addition, when setting NC data, there are cases in which there is a distinction between shape data such as coil diameter and number of turns, and parameter data such as pitch, wire diameter, and material. In this embodiment, these are combined into a plurality of parameters. Of these, parameters related to pitch are used as pitch parameters.
[0016]
Further, in the present embodiment, pitch detection means 30 for detecting an actual measured pitch value when the coil spring forming machine 20 is driven and the coil spring 1 is formed based on the basic NC data is provided. Based on this, the pitch adjusting means 40 is configured to adjust the pitch of the coil spring in accordance with the desired characteristics of the coil spring. Here, in the basic NC data, the pitch indication value is set to be proportional to the pitch target value (for example, the proportionality coefficient is B and the delay component is A). The pitch actual value detected in this way is compared with the pitch target value, and based on the deviation between the pitch actual value and the pitch target value, the delay component with respect to the proportional relationship between the pitch indication value and the pitch target value becomes (A). One adjustment parameter (α) is set. Further, the second adjustment parameter (β) is set so that the proportionality coefficient in the proportional relationship becomes (B).
[0017]
That is, in the pitch adjusting means 40 of the present embodiment, a start position adjusting means 41 is configured, and the operation start position of the pitch tool 21 (shown by a broken line in FIG. 1) is adjusted based on the first adjustment parameter (α). In addition, the movement ratio adjusting means 42 is configured, and the ratio of the movement amount of the pitch tool to the pitch instruction value (that is, the movement ratio) is adjusted based on the second adjustment parameter (β). The pitch of the coil spring is configured to be adjusted to a desired target value. That is, in this embodiment, if the pitch instruction value is X and the pitch target value is Y, it is represented by a linear equation of Y = B · X + A. In this equation, the proportionality coefficient (B) and the delay component (A) Is the target value.
[0018]
The coil spring 1 has a plurality of stages of pitches, and the mounting state of the coil spring 1 according to the present embodiment is used for, for example, a valve system of an internal combustion engine as shown by a two-dot chain line in FIG. Is done. That is, in the engine 2, a valve stem 3 a of a valve 3 (intake valve or exhaust valve) is slidably supported with respect to the stem guide 4, and a retainer 5 is fixed to the tip of the valve stem 3 a, via a valve lifter 6. Are arranged so as to be pressed against the cam 7. A coil spring 1 is interposed between a spring seat (not shown) arranged on the engine 2 around the stem guide 4 and the retainer 5, and the valve 3 biases the valve 3 toward the cam 7 by the coil spring 1. It is configured to be.
[0019]
FIG. 2 shows a pitch adjustment subroutine performed by interrupt processing for a main control routine (not shown) of the coil spring molding machine by the NC controller. The solid line portion in FIG. 2 relates to the above-described embodiment. First, in step 101, a plurality of parameters such as a coil diameter, the number of turns, and a pitch that specify a desired coil spring are set. Here, in this embodiment, the pitch instruction value is set in a predetermined proportional relationship with respect to the pitch target value, and the proportionality coefficient (B) and the delay component (A) are set as the pitch parameters. Subsequently, in Step 102, basic NC data is set based on the plurality of parameters.
[0020]
Then, the process proceeds to Step 103, where a pitch instruction value is input, and when the coil spring molding machine 20 is driven in Step 104, the pitch target set in accordance with the pitch parameters (A, B) is set. A coil spring is formed based on the value. Note that the processing in step 104 is performed according to the NC program, for example, as in the above-mentioned Patent Document 1.
[0021]
As a result, for example, when the coil spring 1 of FIG. 1 is formed, the process proceeds to step 105, where the actual pitch measurement value is detected by the pitch detection means 30, and in step 106, this actual pitch measurement value is compared with the target pitch value. Then, a deviation between the actually measured pitch value and the target pitch value is determined. For example, the target characteristics (inclination B, delay A) indicated by the solid line in FIG. 3 correspond to the proportionality coefficient (B) and the delay component (A), whereas the actual characteristics (indicated by the broken line in FIG. Inclination K and delay F) indicate measured values that are different from the target characteristics for both the inclination and the delay. The horizontal axis in FIG. 3 indicates the pitch instruction value, the vertical axis indicates the actual pitch measurement value, the white circle symbol indicates the damper portion of the target coil spring, and the white triangle symbol indicates the measurement position in the middle of the trunk. A linear equation including an inclination and a delay is obtained based on a measured pitch value with respect to a pitch instruction value at a position (two points).
[0022]
Based on the determination result, in step 107, the first adjustment parameter (α) is set so that the delayed component after molding becomes (A). In step 108, the proportional coefficient after molding is determined. The second adjustment parameter (β) is set so as to be (B). The coil spring molding machine 20 of the present embodiment is configured to be able to adjust the rate of movement of the pitch tool 21 and includes a start position adjusting means 41 and a movement ratio adjusting means 42 indicated by broken lines in FIG. Therefore, the process proceeds to step 109, where the operation start position of the pitch tool 21 with respect to the pitch instruction value is adjusted based on the first adjustment parameter (α), and in step 110, the second adjustment parameter (β) is set. Based on this, the movement ratio of the pitch tool 21 with respect to the pitch instruction value is adjusted.
[0023]
The above situation will be described with reference to FIGS. First, when the operation start position of the pitch tool 21 with respect to the pitch instruction value is adjusted based on the first adjustment parameter (α) from the state of FIG. 3, the target characteristic (inclination) as shown by the one-dot chain line is the characteristic after this adjustment. B, the delay A) coincides with the delay. When the movement ratio of the pitch tool 21 with respect to the pitch instruction value is further adjusted from the state of FIG. 4 based on the second adjustment parameter (β), the adjusted characteristics are indicated by a two-dot chain line in FIG. Both the slope and the delay of the target characteristic (slope B, delay A) match.
[0024]
On the other hand, in the coil spring molding machine in which the proportional coefficient (B) cannot be adjusted, the process proceeds from step 108 to step 111 indicated by a one-dot chain line in FIG. 2, and the first adjustment parameter (α) and the second adjustment parameter ( Basic NC data is reset based on β). In other words, a pitch adjusting device for a coil spring forming machine that cannot adjust the proportional coefficient (B) is configured as another embodiment of the present invention, and the main control routine (not shown) uses the reset NC data in step 111 as the reset NC data. Based on this, the pitch of the coil spring is adjusted.
[0025]
Thus, in this embodiment, the setup time is longer than that in the previous embodiment, but in the state of FIG. 3, the basic adjustment is based on the first adjustment parameter (α) and the second adjustment parameter (β). When the NC data is reset, as shown by the two-dot chain line in FIG. 6 after the adjustment, both the inclination and the delay of the target characteristic (inclination B, delay A) coincide.
[0026]
A simulation result by the pitch adjusting apparatus according to an embodiment of the present invention having the above-described configuration will be described with reference to FIGS. FIG. 7 shows that the load inflection point and the accuracy of the designated load vary with the simulation value 5 after the adjustment with respect to the actually measured value (indicated by the solid line) for the coil spring having the symmetrical two-stage pitch similar to the coil spring S2 of FIG. High accuracy of within% can be achieved. In FIG. 7, the central symbol L1 indicates the simulation value of the first specified load, the upper right symbol L2 indicates the simulation value of the second specified load, and the upper and lower T-shaped line segments indicate the fluctuation range. In the specific example, the actual measurement value 252N with respect to the simulation value 249N at the first designated height 36.0 mm, and the actual measurement value 437N with respect to the simulation value 430N at the second designated height 27.9 mm. FIG. 8 shows similar results for coil springs with unequal pitches at both ends. In a specific example, the simulation value 142N at the first specified height 37.7 mm is compared with the actual measurement value 142N and the simulation at the second specified height 30.5 mm. The actual value 340.95N was identical to the value 340.95N. In addition, the setup time could be shortened from 2 hours to 1 hour.
[0027]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects. That is, in the pitch adjusting method and apparatus according to claims 1 and 3, when forming a coil spring having an unequal pitch or a multi-step pitch, a setup instruction condition that satisfies high pitch accuracy can be obtained accurately and in a short time. it can. Therefore, an appropriate relationship between the target value and the setup value that can accurately respond to a plurality of pitch values can be set according to various spring specifications, and good productivity can be ensured.
[0028]
In the pitch adjusting method and apparatus according to claims 2 and 4, it is possible to accurately obtain a setup instruction condition that satisfies high pitch accuracy when forming a coil spring having an unequal pitch or a plurality of pitches.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention.
FIG. 2 is a flowchart showing a pitch adjustment process according to an embodiment of the present invention.
FIG. 3 is a graph showing a relationship between an actual characteristic and a target characteristic in a state before pitch adjustment according to an embodiment of the present invention.
FIG. 4 is a graph showing a relationship between an actual characteristic and a target characteristic in a state where a delay is dealt with in pitch adjustment according to an embodiment of the present invention.
FIG. 5 is a graph showing a relationship between an actual characteristic and a target characteristic in a state in which a slope and a delay are dealt with in pitch adjustment according to an embodiment of the present invention.
FIG. 6 is a graph showing a relationship between an actual characteristic and a target characteristic in a state in which correspondence to inclination and delay is performed in pitch adjustment according to another embodiment of the present invention.
FIG. 7 is a graph showing an example of the effect when the pitch adjustment according to the embodiment of the present invention is performed on a coil spring having a symmetrical two-stage pitch.
FIG. 8 is a graph showing an example of the effect when the pitch adjustment according to the embodiment of the present invention is performed on a coil spring having unequal pitches at both ends.
FIG. 9 is a side view schematically showing an example of coil springs with unequal pitches.
FIG. 10 is a side view schematically showing an example of a symmetrical two-stage pitch coil spring.
FIG. 11 is a graph showing the relationship between the number of turns and the pitch in a coil spring with an unequal pitch and a coil spring with a symmetrical two-stage pitch.
[Explanation of symbols]
1 coil spring, 10 NC controller, 20 coil spring forming machine,
30 pitch detection means, 40 pitch adjustment means

Claims (4)

NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil spring forming machine for forming the coil spring based on the NC data is set according to the characteristics of the coil spring. In the pitch adjustment method of the coil spring forming machine for adjusting the pitch of the coil spring , Y = B where the pitch instruction value is (X), the pitch target value is (Y), the proportionality factor is (B), and the delay component is (A).・ Set to a predetermined proportional relationship represented by a linear equation of X + A to obtain basic NC data, and based on the basic NC data, the coil spring forming machine is driven to form the coil spring, and the measured pitch value is the pitch target. compared with the values (Y), based on the deviation between the pitch measured value and the pitch target value (Y), the proportional relationship between the pitch measured value and the pitch instruction value (X) Sets the first adjustment parameter to match the delay component of the delay components predetermined proportional relationship (A) (α) against the pitch measured value and the pitch indicated value proportional coefficient in a proportional relationship (X) A second adjustment parameter (β) that matches the proportional coefficient (B) of the predetermined proportional relationship is set, the operation start position of the pitch tool is adjusted based on the first adjustment parameter (α), and the first adjust the ratio of the amount of movement of said pitch tool with respect to the pitch indicated value on the basis of the second adjustment parameter (β) (X), the pitch of the coil spring forming machine and adjusting the pitch of the coil spring Adjustment method. NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil spring forming machine for forming the coil spring based on the NC data is set according to the characteristics of the coil spring. In the pitch adjustment method of the coil spring forming machine for adjusting the pitch of the coil spring , Y = B where the pitch instruction value is (X), the pitch target value is (Y), the proportionality factor is (B), and the delay component is (A).・ Set to a predetermined proportional relationship represented by a linear equation of X + A to obtain basic NC data, and based on the basic NC data, the coil spring forming machine is driven to form the coil spring, and the measured pitch value is the pitch target. the value (Y) and compared on the basis of the deviation between the pitch measured value and the pitch target value (Y), the pitch measured value and the pitch instruction value (X) and the proportional function The basic NC data is reset to be reset NC data so as to match the predetermined proportional relationship, and the pitch of the coil spring is adjusted based on the reset NC data How to adjust the pitch of the machine. NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil spring forming machine for forming the coil spring based on the NC data is set according to the characteristics of the coil spring. In the pitch adjusting device of the coil spring molding machine for adjusting the pitch of the coil spring , Y = B , where the pitch instruction value is (X), the pitch target value is (Y), the proportionality coefficient is (B), and the delay component is (A). A pitch for detecting an actual measured pitch value when the coil spring is formed by driving the coil spring molding machine based on the basic NC data by setting a predetermined proportional relationship represented by a linear expression of X + A. and detecting means, the pitch measured values said pitch detecting means detects as compared to the pitch target value (Y), the pitch measured value and the pitch target value (Y) Based on the deviation, and sets the first adjustment parameter to match with the pitch measured value and the pitch instruction value (X) a delay component of the predetermined proportionality delay component for proportional relationship (A) (α), Adjustment parameter setting means for setting a second adjustment parameter (β) that matches the proportionality coefficient in the proportional relationship between the actually measured pitch value and the pitch indication value (X) with the proportionality coefficient (B) of the predetermined proportionality relationship; with adjusting the operation start position of the pitch tool on the basis of the adjustment parameter setting means wherein the first adjustment parameter set (alpha), with respect to the pitch indicated value on the basis of the second adjustment parameter (β) (X) A pitch of a coil spring forming machine comprising pitch adjusting means for adjusting a pitch of the coil spring by adjusting a rate of movement of the pitch tool. Adjustment device. NC data is set based on a plurality of parameters including at least a pitch parameter for specifying a desired coil spring, and the coil spring forming machine for forming the coil spring based on the NC data is set according to the characteristics of the coil spring. In the pitch adjusting device of the coil spring molding machine for adjusting the pitch of the coil spring , Y = B , where the pitch instruction value is (X), the pitch target value is (Y), the proportionality coefficient is (B), and the delay component is (A). A pitch for detecting an actual measured pitch value when the coil spring is formed by driving the coil spring molding machine based on the basic NC data by setting a predetermined proportional relationship represented by a linear expression of X + A. and detecting means, the pitch measured values said pitch detecting means detects as compared to the pitch target value (Y), the pitch measured value and the pitch target value (Y) Based on the deviation, the re-setting the basic NC data so that pitch measured value and the pitch indicated value proportional relationship between (X) coincides with the predetermined proportional relationship, resetting means for setting a reset NC data And a pitch adjusting device for adjusting the pitch of the coil spring based on the reset NC data set by the resetting device.

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