JP2001039119A - Designing device for tire tread pattern arrangement, designing method for tire tread pattern arrangement, and recording medium with tire tread pattern arrangement design program recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and efficiently design a tread pattern by determining plural pattern elements in random, generating a pattern arrangement according to the result, and correcting the temporary circumference which is a tire circumference of the generated pattern arrangement according to the basic circumference. SOLUTION: In this tire, tread pattern elements 2 with a designated pitch are arranged along in the circumferential direction on both right and left sides, taking the center line 1 as a border. A suitable number of the same pattern elements 2 are gathered to form a pattern element group 3. Further each pattern element 2 is set to plural pitches. IN this case, in designing the tread pattern arrangement by a computer, first the continuation and number of the respective pattern elements 2 are determined in random, according to the result, the tread pattern arrangement is generated, and the tire circumference of the generated tread pattern arrangement is calculated as a temporary circumference. After that, the temporary circumference is corrected to match the basic circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tire tread pattern arrangement designing apparatus, a tire tread pattern designing method, and a recording medium recording a tire tread pattern arrangement design program.

[0002]

2. Description of the Related Art In a pneumatic tire, it is important to reduce noise (pattern noise) generated between a road surface and a tire tread when the tire runs on a road. Various tread patterns such as those described in Japanese Patent No. 2709184 have been proposed. As a method of designing a tread pattern with low noise, first, a designer determines a pattern arrangement for one circumference of a tire by considering the arrangement of a plurality of tread pattern elements having different pitches.

[0003] The noise generated by the pattern arrangement is simulated by a computer, the noise generated by the simulation is frequency-analyzed, and the analysis result is output on paper. Such frequency analysis is based on SAE (Society of
Automotive Engineering) Paper No.690520. The designer has determined whether or not the frequency dispersion is good, that is, whether or not the noise is small, by looking at the analysis result.

[0004]

In this conventional method,
The designer performs a series of tasks of pattern array creation, frequency analysis, and judgment in a straightforward manner.
It could be performed only about 10 times a day (8 hours), and the efficiency was low. In particular, pattern array creation is performed based on the experience of a designer, and it has been very difficult to automate such a designer's experience by computerization. The present invention has been made in view of such a problem, and an object of the present invention is to make designing of a tread pattern easy and efficient.

[0005]

In order to solve the above-mentioned problems, the present invention employs the following technical means. That is,
A feature of the present invention is a tread pattern array of a tire having a plurality of types of tread pattern elements having different pitches, wherein a pattern element group in which one or a plurality of the same pattern elements are continuously arranged is formed. An apparatus for designing, by a computer, a tread pattern array in which an element group is arranged in a tire circumferential direction, a random number generating means for randomly determining a continuous arrangement number of each pattern element, and a continuous arrangement number of the determined pattern elements And a pattern generating means for generating a tread pattern array based on the

It is preferable that the apparatus further comprises a setting means for setting a numerical range of the number of continuous rows determined by the random number generating means. Further, provisional circumference calculating means for calculating, as a provisional circumference, a tire circumference of a tread pattern array generated based on the determined number of continuous arrangements of each pattern element and a predetermined pitch length of each pattern element. And correcting means for correcting the temporary circumference so that the temporary circumference matches the basic circumference based on a deviation between the temporary circumference and a predetermined basic circumference of the tire. Is preferred.

It is preferable that the correction means corrects the pitch length of each pattern element based on a ratio of the temporary circumference to the basic length so that the temporary circumference matches the basic circumference. . Furthermore, simulation means for simulating the noise generation of the tire on which the tread pattern with the corrected pitch length is formed, and determination means for determining whether the noise level by the simulation of the tire is equal to or less than a predetermined reference. Is preferred. It is preferable that the apparatus further includes an array diagram output unit that outputs a tread pattern array diagram in which the noise level is determined to be equal to or less than a predetermined reference by the determination unit in the generated tread pattern array.

It is preferable that the apparatus further comprises a pitch output means for outputting the pitch length corrected by the correction means. Further, it is preferable to provide a repetition means for automatically and repeatedly performing a process from generation of the tread pattern array to determination of the noise level. An apparatus according to the present invention is an apparatus for designing, by a computer, a tread pattern arrangement of a tire in which a plurality of types of tread pattern elements having different pitches are arranged in a circumferential direction, and automatically generates a large number of different pattern arrangement candidates. Pattern candidate generation means, simulation means for simulating noise generation of the created pattern arrangement candidate, and determination means for determining whether the noise level due to the simulation is equal to or less than a predetermined reference, may be provided. it can.

Further, according to the method of the present invention, there is provided a tread pattern array of a tire having a plurality of types of tread pattern elements having different pitches, wherein the same pattern element is one.
Comprising a group of pattern elements arranged one or more consecutively,
A method for designing, by a computer, a tread pattern array in which each pattern element group is arranged in the tire circumferential direction, wherein a step of randomly determining the number of consecutive arrangements of each pattern element is performed. And generating a tread pattern array based on the tread pattern array.

The recording medium on which the program according to the present invention is recorded is a tire tread pattern array having a plurality of types of tread pattern elements having different pitches,
A recording medium that records a program for designing a tread pattern array in which a pattern element group in which one or a plurality of the same pattern elements are continuously arranged and the pattern element groups are arranged in the tire circumferential direction by a computer. The program is characterized in that the number of consecutive arrangements of each pattern element is randomly determined, and a tread pattern array is generated based on the determined number of consecutive arrangements of pattern elements.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 illustrate a tread pattern of a tire created by the device of the present invention. FIG. 1 is a partial development view of a tread pattern element array of a pneumatic tire, showing specific shapes of tread pattern elements. FIG. 2 shows a pattern element arrangement diagram in a mold for producing a tire.
In FIG. 1, reference numeral 1 denotes a center line of the tire (equatorial line of the tire tread), and tread pattern elements 2 having a predetermined pitch are arranged along the circumferential direction on both left and right sides through the center line 1.

In the arrangement order of the pattern elements 2, one or two or more identical pattern elements 2 constitute a pattern element group 3 in a group. 1 and 2, the pattern elements 2 have five pitches. Hereinafter, these five types of pattern elements are referred to as P1, P2, P3, P4, and P5, respectively, and their pitch lengths are referred to as L1, L2, L3, L4, and L5, respectively.
That is, the length of the pattern element Pi is Li (i is a number from 1 to 5). The design device of the present invention is configured by a personal computer in which a tread pattern design program is stored in a storage device. Although not shown, the computer mentioned here may include input devices such as a keyboard and a mouse, output devices such as a display and a printer, and other peripheral devices such as an auxiliary storage device if necessary. Further, the program of the present embodiment is created in BASIC, and the means for realizing the functions of the device 1 is achieved by the functions or procedures of BASIC in addition to the functions of the computer itself. .

To generate the tread pattern shown in FIG. 2, first, as shown in FIG. 3, an operator inputs necessary data to a computer as a design device (step S).
1). The input data includes the total pitch number T in the circumferential direction, the tire circumference (basic circumference) Bcir (unit: mm), the pitch length Li of each tread pattern element (unit: mm), and the A maximum value M (range) in a continuous list, a noise level determination criterion X, a random number sequence S, and other additional information (date and the like) A. FIG. 4 shows an example of the input of these data. Note that a tire diameter may be input instead of the tire circumference Bcir (the tire circumference can be calculated by diameter × π).

When the apparatus receives the data group and has the necessary information, a process of generating a tread pattern array is performed (step S2). The purpose of this generation processing is to create an array of pattern elements 2 for one circumference of the tire as shown in FIG. Here, five types of tread pattern elements are assumed, and the five types of tread pattern elements are P1, P2, P3, P4, P5, P
4, P3, P2,... That is, i of Pi is increased from 1 to the maximum value (here, 5) (ascending order), and when i reaches the maximum value (5), it is decreased to the minimum value (here, 1) (descending order). (I: imin->imax->imin->...) Therefore, the basic policy for creating a pattern array is that the pattern elements are arranged consecutively in accordance with the above-described array order rule. What is necessary is just to determine the number of arrangement.

Specifically, first, the number of consecutive rows of P1 is randomly determined within a range of the maximum value M of the inputted number of consecutive rows. The number of continuous lines is determined by a random number R (R
Is multiplied by the maximum value M (5 in the input of FIG. 4) of the number of continuous lines. The portion after the decimal point of R × M is rounded (rounded down, rounded up or rounded off, etc.) to determine the number of consecutive integers in the range of 1 to 5. In order to prevent the same random number from being generated each time the program is executed,
A plurality (99) of random number sequences for generating random numbers are prepared, and the user selects and inputs an arbitrary random number sequence S from the plurality of random number sequences.

With the above processing, the number of consecutive rows of P1 is determined (in FIG. 5, the number of consecutive rows of P1 is determined to be 1). Next, the number of consecutive rows of P2 is determined according to the arrangement order rule. The number of consecutive rows of P2 is also determined by the same processing as that of P1 (2 is determined in FIG. 5). Such processing is performed until a predetermined end condition is reached, and the number of continuous pattern elements 2 for one rotation of the tire is determined. The predetermined end condition is a case where the determined total number of the continuous arrangement numbers matches the input total pitch number T in the circumferential direction.
The total number of consecutive arrangements is obtained by accumulating the consecutive arrangement number of each pattern element 2 in a counter, and the value of the counter is compared with the total pitch number T to determine whether they match.

If the value of the counter is less than the total pitch number T, the process of determining the number of continuous rows is repeated. If the value of the counter matches the total pitch number T, the process of determining the number of continuous rows is terminated. The value of the counter is the total pitch number T
Is exceeded, the counter is cleared to zero, and the process of determining the number of consecutive rows is performed from the beginning. If the value of the counter exceeds the total pitch number T, the processing is not started over from the beginning, but is subtracted from the last determined continuous arrangement number by the amount exceeding the total pitch number, and the subtracted number is calculated. The processing may be terminated by setting the number of continuous rows.

As a result of the above processing, a pattern arrangement for one rotation of the tire is generated. In the present invention, since random numbers are used to determine the number of continuous arrangements, a large number of pattern arrays can be automatically generated. Therefore,
Large amounts of pattern arrays can be generated by computer. Next, since the tire circumference (Li × the number of each element) based on the pattern arrangement generated by the above processing often does not match the input tire circumference Bcir, in order to match this, the following is used. A correction process (step S3) is performed.

The correction is performed by correcting each pitch length Li based on the ratio of the tire circumference of the generated pattern arrangement to the tire circumference (basic circumference) Bcir given in advance by input. . Specifically, first, a circumferential length ratio Cr between the tire circumferential length (temporary circumferential length) of the generated array and the input tire circumferential length Bcir is determined as in the following Expression 1.

[0020]

(Equation 1)

Next, as shown in the following equation 2, each pitch length L
The pitch length Li is corrected by multiplying i by the circumference ratio Cr.

[0022]

(Equation 2)

This correction process will be described with a specific example. First,
Assuming five types of pattern elements, the given basic circumference Bcir is 1885, and the given number of circumferential pitches T is 6
It is assumed that the given pitch length Li and the number Lin of each element existing in the generated pattern array are as follows. P1: L1 = 25.0 (L1n: 7 pieces) P2: L2 = 26.0 (L2n: 12 pieces) P3: L3 = 27.0 (L3n: 15 pieces) P4: L4 = 28.0 (L4n: 10 P5: L5 = 29.0 (L5n: 16) In this case, the temporary circumference is 25.0 * 7 + 26.0 * 12 + 27.0 * 15 + 28.0 * 10
+ 29.0 * 16 = 1636 (mm), this temporary circumference and the basic circumference Bc
From equation (1), the circumference ratio Cr is obtained from Equation 1 to find that Cr = 1
885/1636 = 1.15.

From the circumferential length ratio Cr, the pitch length L can be calculated according to Equation 2.
i is corrected as follows. L1 = 25.0 × 1.15 = 28.75 L2 = 26.0 × 1.15 = 29.9 L3 = 27.0 × 1.15 = 31.05 L4 = 28.0 × 1.15 = 32 .2 L5 = 29.0 × 1.15 = 33.35 By the above-described pitch length Li correction processing, the circumference of the generated pattern array can be made to coincide with the target basic circumference Bcir. Further, since the correction process is performed, the pitch length Li to be input does not have to be strict, so that the burden on the user is reduced.

Next, an arrangement diagram (corresponding to FIG. 2) of the determined pattern arrangement is displayed on the display (step S4). Subsequently, the computer simulates the tire noise generation based on the determined pattern arrangement, and performs a frequency analysis process of the noise generated by the simulation (step S5). For this process,
As described above, it is disclosed in SAE Paper No. 690520.
The noise level of the tire based on the generated pattern arrangement is obtained by the frequency analysis, and it is determined whether or not this noise level is equal to or less than the input noise level criterion X (14 in FIG. 4) (step S6).

If the noise level exceeds the criterion X, the fact that the level is over is printed out (step S7), and the process returns to step S2. If it is equal to or smaller than the determination criterion X, the pattern arrangement diagram, the corrected pitch length, etc. are printed out on paper (step S8), and the process returns to step S2. FIG. 6 shows, in addition to the pattern arrangement diagram printed out at a good noise level, the number Lin of each element in the arrangement, the corrected pitch length Li, and the like. The processing of steps S2 to S8 is repeated unless the forced termination processing is performed. The forced termination can be performed by pressing "ST
Pressing the "OP" key interrupts the process and stops the program.

By performing the repetitive processing, a pattern array having a low noise level is output as an array diagram from a large number of generated pattern arrays. In this program, a large number of pattern array candidates (samples) are generated, and a process (optimum pattern array search) for discriminating between those candidates having good noise levels and those having poor noise levels is performed. Since the output is performed, the designer only has to select an appropriate pattern arrangement from the output pattern arrangement having a good noise level. Further, since the corrected pitch length is also output, a mold for manufacturing a tire can be designed based on the corrected pitch length.

In the above processing, the user
Since only the first input and the end operation for stopping the program need to be performed, there is no case in which the designer cannot perform the design unless the user has to do his or her work. Therefore, this program can be executed at night, and tens of thousands of patterns can be generated and checked a day, thereby greatly reducing the burden on the designer. Note that the present invention is not limited to the above embodiment. In the present invention, the following changes are possible.

The arrangement order rule of the pattern element 2 is, for example,
P1, P2, P3, P4, P5, P1, P2, P3,.
.., As in the case of increasing the value of Pi from 1 to the maximum value, and increasing the value of i again from 1 when the value of i reaches the maximum value. It may be. Further, instead of the arrangement order according to a certain rule, i of Pi may be randomly determined by a random number generated by a computer. Thus, the arrangement order of the pattern elements 2 may be regular or random. Further, any of a plurality of arrangement methods may be prepared and one of the arrangement methods may be selected (the arrangement method is input and selected in step S1).

As a method of randomly generating the number of continuous arrangements of pattern elements, any method may be used as long as a numerical value can be randomly determined within a set range. Also,
Although the minimum value of the number of consecutive rows is assumed to be 1 and only the maximum value M is input and set, the range of the number of consecutive rows may be set more freely by inputting the minimum value. The ending condition of the continuous arrangement number determination process may be any condition as long as the pattern arrangement for one circumference of the tire can be determined. For example, the determined continuous arrangement number is multiplied by the pitch length Li, and is determined during the process. In the case where the determined circumferential length is smaller than the tire circumferential length Bcir, the process of determining the number of continuous rows is repeated until the determined circumferential length is equal to the circumferential length. When the length Bcir matches, or when the value becomes close to the circumference Bcir, the process of determining the number of consecutive rows can be terminated. If the determined circumferential length does not coincide with the circumferential length Bcir, the pitch length Li of the pattern element may be corrected.

The process for correcting the pitch length Li is not limited to the above embodiment. The purpose of the correction processing is to make the provisional circumference and the target tire circumference Bcir coincide with each other, and this can be achieved by increasing or decreasing the number Lin of each element in addition to increasing or decreasing the pitch length Li. . For example, when the provisional circumference is smaller than the tire circumference Bcir, the number Lin of any of the pattern elements is increased, and when the provisional circumference is larger than the tire circumference Bcir, the number Lin of any of the pattern elements is reduced. Alternatively, the temporary circumference and the tire circumference Bcir can be made to match. If the number of pattern elements does not match sufficiently even when the number of pattern elements increases or decreases, fine adjustment can be made by increasing or decreasing any of the pitch lengths Li.

The output of the pattern arrangement having a good noise level is not limited to the print output, but may be, for example, output to a file, that is, output to a storage device. In this program, the number of types of pattern elements is five, but any number (plural) can be used. In order to select an arbitrary number, for example, at the time of the first input (step S1), the number of types of pattern elements is input, or five, four, three, It is possible to prepare a plurality of programs corresponding to types such as personal use, store them in a storage device, and select and execute any one of the programs.

In the above embodiment, this processing was repeated with the pattern array generation, frequency analysis, and determination as one cycle. However, a large number of pattern arrays were generated first, and many samples for frequency analysis were prepared. After that, frequency analysis or the like may be performed collectively.

[0034]

As described above, according to the present invention, a large amount of pattern arrangement is automatically generated, so that the design of the tread pattern can be made easy and efficient.

[Brief description of the drawings]

FIG. 1 is a partial development view of a tread pattern element array of a tire.

FIG. 2 is an arrangement diagram of pattern elements in a mold for producing a tire.

FIG. 3 is a flowchart of a program according to the present invention.

FIG. 4 is a screen diagram showing an example of data input.

FIG. 5 is a diagram illustrating an example of a data structure of a pattern element arrangement order and a continuous arrangement number.

FIG. 6 is a diagram illustrating a print output example.

[Explanation of symbols]

 2 Pattern element 3 Pattern element group T Number of pitches in the circumferential direction Bcir Basic circumference Li Pitch length of pattern element

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[Procedure amendment]

[Submission date] April 6, 2000 (200.4.6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

In order to solve the above-mentioned problems, the present invention employs the following technical means. That is,
A feature of the present invention is a tread pattern array of a tire having a plurality of types of tread pattern elements having different pitches, wherein a pattern element group in which one or a plurality of the same pattern elements are continuously arranged is formed. An apparatus for designing, by a computer, a tread pattern array in which an element group is arranged in a tire circumferential direction, a random number generating means for randomly determining a continuous arrangement number of each pattern element, and a continuous arrangement number of the determined pattern elements Pattern generation means for generating a tread pattern array based on the
The number of consecutive arrangements of each pattern element
Tread generated based on the pitch length of the turn element
Temporary circumference that calculates the tire circumference of the pattern array as the temporary circumference
Length calculating means, and the provisional circumference and the tire base given in advance.
The temporary circumference becomes the basic circumference based on the deviation from the actual circumference.
And a correcting means for correcting the provisional circumference so that they coincide with each other.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

It is preferable that the apparatus further comprises a setting means for setting a numerical range of the number of continuous rows determined by the random number generating means.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

Further, according to the method of the present invention, there is provided a tread pattern array of a tire having a plurality of types of tread pattern elements having different pitches, wherein the same pattern element is one.
Comprising a group of pattern elements arranged one or more consecutively,
A method for designing, by a computer, a tread pattern array in which each pattern element group is arranged in the tire circumferential direction, wherein a step of randomly determining the number of consecutive arrangements of each pattern element is performed. Generating a tread pattern array based on the determined
The number of consecutive arrangements of each pattern element
Tread generated based on the pitch length of the turn element
Calculate the tire circumference of the pattern array as the temporary circumference
Between the temporary circumference and the basic circumference of the tire given in advance.
The temporary circumference will match the basic circumference based on the length deviation.
Correcting the temporary circumference as described above.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

The recording medium on which the program according to the present invention is recorded is a tire tread pattern array having a plurality of types of tread pattern elements having different pitches,
A recording medium that records a program for designing a tread pattern array in which a pattern element group in which one or a plurality of the same pattern elements are continuously arranged and the pattern element groups are arranged in the tire circumferential direction by a computer. The program randomly determines the number of consecutive arrangements of each pattern element, generates a tread pattern array based on the determined number of consecutive arrangements of pattern elements, and determines
The number of consecutive pattern elements
The track generated based on the pitch length of the pattern element
Calculate the tire circumference of the tire pattern array as the temporary circumference,
The length between the provisional circumference and the basic circumference of the tire given in advance.
Based on the deviation, the temporary circumference is temporarily adjusted to match the basic circumference.
It is characterized in that the circumference is corrected .

Claims (11)

[Claims] 1. A tread pattern array of a tire having a plurality of types of tread pattern elements (2) having different pitches, wherein one or a plurality of the same pattern elements (2) are continuously arranged. An apparatus for designing a tread pattern array in which each pattern element group (3) is arranged in the tire circumferential direction by a computer, wherein the number of continuous arrangements of each pattern element (2) is randomly determined. An apparatus for designing a tire tread pattern array, comprising: a random number generating means; and a pattern generating means for generating a tread pattern array based on the determined number of continuous pattern elements. 2. The tire tread pattern array designing apparatus according to claim 1, further comprising a setting unit for setting a numerical range of the number of continuous rows determined by the random number generating unit. 3. The determined number of successive arrangements of each pattern element, and a predetermined pitch length (Li) of each pattern element
Means for calculating the tire circumference of the tread pattern array generated on the basis of the above as a temporary circumference; and a temporary circumference (Bci)
r), the temporary circumference is set to the basic circumference (Bc
3. The tire tread pattern array designing apparatus according to claim 1, further comprising: a correction unit configured to correct a provisional circumference so as to coincide with ir). 4. The method according to claim 1, wherein the correcting means includes a provisional circumference and a basic circumference (B
cir), the provisional circumference is set to the basic circumference (Bc
ir) to match the pitch length (L) of each pattern element.
The tire tread pattern array designing apparatus according to claim 3, wherein i) is corrected. 5. A simulation means for simulating noise generation of a tire on which a tread pattern having a corrected pitch length (Li) is formed, and determining whether a noise level by the simulation of the tire is equal to or lower than a predetermined reference (X). The tire tread pattern designing apparatus according to claim 3, further comprising: a determination unit configured to perform the determination. 6. An arrangement diagram output means for outputting a tread pattern arrangement map in which a noise level is determined by the determination means to be equal to or lower than a predetermined reference among the generated tread pattern arrangements. A tire tread pattern designing apparatus according to claim 5. 7. The tire tread pattern arrangement designing apparatus according to claim 3, further comprising a pitch output unit that outputs a pitch length corrected by the correction unit. 8. The tire tread according to claim 4, further comprising a repetition means for automatically and repeatedly performing a process from generation of a tread pattern array to determination of a noise level. Design equipment for pattern arrangement. 9. An apparatus for designing, by a computer, a tread pattern array of a tire in which a plurality of types of tread pattern elements (2) having different pitches are arranged in a circumferential direction, wherein the pattern automatically generates a large number of different pattern array candidates. A tire comprising: candidate generation means; simulation means for simulating noise generation of the created pattern arrangement candidates; and determination means for determining whether a noise level due to the simulation is equal to or lower than a predetermined reference. Tread pattern array design equipment. 10. A tread pattern array of a tire having a plurality of types of tread pattern elements (2) having different pitches, wherein one or a plurality of the same pattern elements (2) are continuously arranged. 3) is a method of designing, by a computer, a tread pattern array in which each pattern element group (3) is arranged in the tire circumferential direction, wherein the number of consecutive arrangements of each pattern element (2) is randomly determined. A method for designing a tire tread pattern array, comprising: a step of generating a tread pattern array based on the determined continuous number of pattern elements (2). 11. A tread pattern array of a tire having a plurality of types of tread pattern elements (2) having different pitches, wherein one or a plurality of the same pattern elements (2) are continuously arranged. 3) is a recording medium on which a program for designing a tread pattern array in which each pattern element group (3) is arranged in the tire circumferential direction by a computer is recorded, and the program includes each pattern element (2) A tire tread pattern array design program which randomly determines the number of continuous arrays of the tread pattern array and generates a tread pattern array based on the determined number of continuous arrays of the pattern elements (2).