Strand detection system, control device, control method, and control program

Abstract

A strand detection system 1 comprises: a support mechanism 4 that supports a coil spring W and allows the coil spring W to rotate around a specific axis Ax on a central axis of the coil spring W; a sensor 5 that measures the outer shape position of the strand of the coil spring W and outputs strand data; and a control device 3 that controls operations of the support mechanism 4 and the sensor 5. The control device 3 comprises: a support mechanism control unit that operates the support mechanism 4 and rotates the coil spring W around the specific axis Ax; a sensor control unit that operates the sensor 5 and acquires strand data from the sensor 5; and a target strand detection unit that detects the outer shape position of a target strand among the outer shape positions of the strand of the coil spring W included in the strand data.

Description

Technical Field

[0001] The present invention relates to a strand detection system, a control device, a control method, and a control program.

Background Art

[0002] Conventionally, the following shape measurement methods are known as methods for measuring the shape of a coil spring (see, for example, Patent Document 1). In the shape measurement method described in Patent Document 1, linear slit light that spreads in the axial direction of a coil spring fixed to a rotary stage is irradiated onto the surface of the coil spring, and the reflected light is photographed by a camera to acquire strand data. Then, in this shape measurement method, the strand data and the rotation angle when the coil spring is rotated around its axis are stored in association with each other, and the shape of the coil spring is measured by performing image processing on the strand data.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] <0​​​​​​The present invention has been made in view of the above, and aims to provide a wire detection system, control device, control method, and control program that can appropriately detect a target wire from wire data. [Means for solving the problem]

[0006] To solve the above-mentioned problems and achieve the objective, the wire detection system according to the present invention comprises a support mechanism that supports a coil spring and allows the coil spring to rotate about a specific axis that follows the central axis of the coil spring; a sensor that measures the outer shape position of the wires of the coil spring and outputs wire data; and a control device that controls the operation of the support mechanism and the sensor. The control device comprises a support mechanism control unit that operates the support mechanism and rotates the coil spring about the specific axis; a sensor control unit that operates the sensor and acquires the wire data from the sensor; and a target wire detection unit that detects the outer shape position of a target wire among the outer shape positions of the wires of the coil spring included in the wire data.

[0007] Furthermore, in the wire detection system according to the present invention, the wire data includes outline equivalent points corresponding to the outline positions of the wires of the coil spring measured by the sensor on a sensor coordinate axis that includes a first axis extending from the sensor toward the object to be measured and a second axis perpendicular to the first axis. The target wire detection unit refers to the wire data and performs a search process to move a virtual line parallel to the first axis along the second axis from a specific search start position on the second axis and extract the outline equivalent points located on the virtual line. The unit detects a plurality of such outline equivalent points extracted consecutively by the search process as the outline positions of the target wires.

[0008] Furthermore, in the wire detection system according to the present invention, the target wire detection unit detects the outline position of the target wire, which includes the outline equivalent points extracted when the virtual line is moved with the smallest amount of movement from the search start position, among the outline equivalent points extracted when the virtual line is moved in a first direction along the second axis from the search start position, and the outline equivalent points extracted when the virtual line is moved in a second direction opposite to the first direction along the second axis from the search start position.

[0009] Furthermore, in the strand detection system according to the present invention, the target strand detection unit repeatedly performs the detection of the outer shape position of the target strand by the search process at a specific control cycle, and in the search process in the next control cycle after the detection of the outer shape position of the target strand, the second axial center position of the outer shape position of the target strand is set as the search start position.

[0010] Furthermore, in the wire detection system according to the present invention, the target wire detection unit extracts only those outline equivalent points where the distance between adjacent outline equivalent points in the second axial direction is less than or equal to a specific first threshold through the search process.

[0011] Furthermore, in the wire detection system according to the present invention, if the number of the plurality of outline equivalent points is less than or equal to a specific second threshold, the target wire detection unit repeats the search process and detects the outline position of the target wire again.

[0012] Furthermore, the wire detection system according to the present invention further comprises a coating device for applying a coating material to the coil spring, and the control device comprises a coating position calculation unit that calculates the coating position on the target wire based on the outer shape position of the target wire, a movement control unit that moves the coating device and the support mechanism relative to each other and positions the coating device at a position where the coating material is applied to the coating position from the coating device, and a coating device control unit that operates the coating device and applies the coating material to the coating position from the coating device.

[0013] Furthermore, the wire detection system according to the present invention further comprises a moving device that supports the coating device and moves the coating device, and the moving control unit operates the moving device to position the coating device at a position where the coating material is applied from the coating device to the coating position.

[0014] Furthermore, in the wire detection system according to the present invention, the sensor measures the outer shape position of the wires of the coil spring from directions that intersect the specific axis and the plane perpendicular to the specific axis, respectively.

[0015] Furthermore, the control device according to the present invention includes a support mechanism control unit that operates a support mechanism that supports a coil spring and rotates the coil spring about a specific axis that follows the central axis of the coil spring; a sensor control unit that operates a sensor that measures the outer shape position of the strands of the coil spring and outputs strand data, and acquires the strand data; and a target strand detection unit that detects the outer shape position of a target strand from among the outer shape positions of the strands of the coil spring included in the strand data.

[0016] Furthermore, the control method according to the present invention is a control method executed by a control device of a wire detection system, and includes a support mechanism control step of operating a support mechanism that supports a coil spring and rotating the coil spring about a specific axis that follows the central axis of the coil spring; a sensor control step of operating a sensor that measures the outer shape position of the wires of the coil spring and outputs wire data, and acquiring the wire data; and a target wire detection step of detecting the outer shape position of a target wire among the outer shape positions of the wires of the coil spring included in the wire data.

[0017] Furthermore, the control program according to the present invention is a control program that causes a computer to execute the following steps: a support mechanism control step which operates a support mechanism that supports a coil spring and rotates the coil spring about a specific axis that follows the central axis of the coil spring; a sensor control step which operates a sensor that measures the outer shape position of the strands of the coil spring and outputs strand data and acquires the strand data; and a target strand detection step which detects the outer shape position of a target strand from among the outer shape positions of the strands of the coil spring included in the strand data. [Effects of the Invention]

[0018] According to the wire detection system, control device, control method, and control program of the present invention, a target wire can be appropriately detected from wire data. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a diagram showing the configuration of a coating material application system according to an embodiment. [Figure 2] Figure 2 illustrates the positional relationship between the sensor and the dispenser. [Figure 3] Figure 3 is a block diagram showing the configuration of the control device. [Figure 4] Figure 4 is a flowchart showing the control methods performed by the control device. [Figure 5] Figure 5 is a flowchart showing the target wire detection step (step S4). [Figure 6] FIG. 6 is a diagram for explaining the target wire detection step (step S4). [Figure 7] FIG. 7 is a diagram for explaining step S5. [Figure 8] FIG. 8 is a diagram for explaining step S4A in the next control cycle. [Figure 9] FIG. 9 is a diagram for explaining Modification Example 1 of the embodiment. [Figure 10] FIG. 10 is a diagram for explaining Modification Example 2 of the embodiment. MODE FOR CARRYING OUT THE INVENTION

[0020] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings. Note that the present invention is not limited by the embodiments described below. Further, in the description of the drawings, the same parts are denoted by the same reference numerals. Hereinafter, a case where the wire detection system according to the present invention is applied to a coating material application system for applying a coating material to a coil spring will be described as an example.

[0021] Outline Configuration of Coating Material Application System FIG. 1 is a diagram showing the configuration of a coating material application system 1 according to the embodiment. As shown in FIG. 1, the coating material application system 1 includes a coating material application device 2 and a control device 3. In the coating material application system 1, under the control of the control device 3, the coating material application device 2 operates to apply a coating material such as a thermosetting resin or a thermoplastic resin to a specific position (coating position) of the coil spring W. Here, the coating position is a portion where the wires of the coil spring W contact each other when the coil spring W is compressed. That is, by applying the coating material to the coating position, the contact damage between the wires of the coil spring W at the coating position is alleviated. In the present embodiment, the cross-sectional shape of the wire of the coil spring W is "rectangular" (see FIGS. 6 and 7).

[0022] [Configuration of the coating material application device] First, let's explain the configuration of the coating material application apparatus 2. In explaining the configuration of the coating material application apparatus 2, the axis along the vertical direction (up and down direction in Figure 1) will be referred to as the Z-axis (Figure 1), and one of the two axes perpendicular to the Z-axis (the axis along the left and right direction in Figure 1) will be referred to as the Y-axis (Figure 1). As shown in Figure 1, the coating material application apparatus 2 comprises a support base 4, a sensor 5, a first moving device 6, a dispenser 7, and a second moving device 8.

[0023] The support base 4 corresponds to the support mechanism according to the present invention. As shown in Figure 1, the support base 4 supports the coil spring W. Specifically, the coil spring W is placed on the support base 4 in a position where its central axis follows the Z-axis. The support base 4 is configured to include a servo motor and the like, and is configured to rotate around a specific axis Ax (Figure 1) that follows the central axis of the coil spring W, under the control of the control device 3. In this embodiment, the specific axis Ax is an axis parallel to the Z-axis.

[0024] Sensor 5 measures the outer shape position of the individual wires of the coil spring W under the control of the control device 3. In this embodiment, sensor 5 is composed of a laser sensor. More specifically, sensor 5 emits laser light in a line along the YZ plane from a direction tilted at 45° with respect to the Y and Z axes. Sensor 5 is configured to measure the profile of the portion of the individual wires that reflects the line-shaped laser light by receiving the laser light reflected from the individual wires of the coil spring W with an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor). Sensor 5 also outputs wire data measuring the outer shape position of the individual wires of the coil spring W to the control device 3. Note that the tilt angle of sensor 5 with respect to the Y and Z axes is not limited to 45°, and other tilt angles may be used.

[0025] The first moving device 6 supports the sensor 5 and moves the sensor 5. As shown in Figure 1, the first moving device 6 comprises a slider 61 that supports the sensor 5, a guide rail 62 that extends along the Z axis, and a servo motor (not shown), etc. In the first moving device 6, under the control of the control device 3, the slider 61 moves along the Z axis on the guide rail 62. In other words, in this embodiment, the first moving device 6 moves the sensor 5 only along a specific axis Ax.

[0026] The dispenser 7 corresponds to the coating apparatus according to the present invention and applies the coating material to the coil spring W under the control of the control device 3. Note that the coating apparatus according to the present invention is not limited to the dispenser 7; other coating apparatuses may also be used.

[0027] The second moving device 8 corresponds to the moving device according to the present invention, supports the dispenser 7, and moves the dispenser 7. As shown in Figure 1, the second moving device 8 includes a slider 81 that supports the dispenser 7, a guide rail 82 extending along the Y axis, a guide rail 83 extending along the Z axis, and a servo motor (not shown), etc. In the second moving device 8, under the control of the control device 3, the slider 81 moves along the Y axis on the guide rail 82, and the guide rail 82 moves along the Z axis on the guide rail 83. In other words, in this embodiment, the second moving device 8 moves the dispenser 7 only along a specific axis Ax and the Y axis, respectively.

[0028] [Regarding the relative positions of the sensor and dispenser] Next, the positional relationship between the sensor 5 and the dispenser 7 described above will be explained. Figure 2 illustrates the positional relationship between sensor 5 and dispenser 7. Specifically, Figure 2 shows sensor 5 and dispenser 7 viewed from above along the Z-axis. As shown in Figure 2, the measurement position PM of the outer shape of the wires of the coil spring W by the sensor 5 and the application position PA of the coating material to the coil spring W by the dispenser 7 are offset by a specific angle around a specific axis Ax.

[0029] In this embodiment, the sensor 5 emits a linear laser beam as described above and measures the profile of the portion of the coil spring W wire that reflects the linear laser beam. Therefore, the measurement position PM corresponds to the position of that portion. In this embodiment, the specific angle is 180°. However, the specific angle is not limited to 180° and may be any other angle.

[0030] [Control device configuration] Next, the configuration of the control device 3 will be described. Figure 3 is a block diagram showing the configuration of the control device 3. The control device 3 controls the operation of the entire coating material application apparatus 2. As shown in Figure 3, the control device 3 comprises an input unit 31, a storage unit 32, and a control unit 33. The input unit 31 consists of buttons, switches, touch panels, etc. that accept user operations and outputs signals corresponding to those user operations to the control unit 33.

[0031] The storage unit 32 stores various programs executed by the control unit 33 (including the control program according to the present invention), as well as data necessary when the control unit 33 performs processing.

[0032] The control unit 33 is realized by executing various programs stored in the memory unit 32 using a controller such as a CPU (Central Processing Unit) or MPU (Micro Processing Unit), and controls the operation of the entire coating material application system 1. The control unit 33 is not limited to a CPU or MPU; it may also be composed of integrated circuits such as an ASIC (Application Specific Integrated Circuit) or FPGA (Field-Programmable Gate Array). As shown in Figure 3, the control unit 33 comprises a support base control unit 331, a sensor control unit 332, a first movement control unit 333, a target strand detection unit 334, a coating position calculation unit 335, a second movement control unit 336, and a coating device control unit 337. Here, the support base control unit 331 corresponds to the support mechanism control unit according to the present invention. The second movement control unit 336 also corresponds to the movement control unit according to the present invention. The detailed functions of the support base control unit 331, sensor control unit 332, first movement control unit 333, target wire detection unit 334, coating position calculation unit 335, second movement control unit 336, and coating device control unit 337 will be explained later in the section "Control Method Executed by the Control Device".

[0033] [Control method executed by the control device] Next, the control method executed by the control device 3 will be described. Figure 4 is a flowchart showing the control method performed by the control device 3. The operator places the coil spring W to be coated onto the support base 4. Then, the operator initiates the coating start operation on the input unit 31. As a result, the control device 3 executes the control method shown below.

[0034] First, the support base control unit 331 rotates the support base 4 at a specific rotational speed around a specific axis Ax (Step S1: Support mechanism control step). Here, the memory unit 32 stores data indicating the specific rotation speed. Then, in step S1, the support base control unit 331 reads this data from the memory unit 32 and rotates the support base 4 at the rotation speed based on this data. Note that the value of this rotation speed can be changed by user operation on the input unit 31.

[0035] After step S1, the sensor control unit 332 operates the sensor 5 and causes the sensor 5 to measure the outer shape position of the individual strands of the coil spring W. Then, the sensor control unit 332 acquires the strand data from the sensor 5 (step S2: sensor control step). Here, as described above, sensor 5 is configured to measure the profile of the individual strands of the coil spring W. Sensor 5 then outputs the position coordinates of each part of the individual strands of the coil spring W that reflect the line-shaped laser light output from sensor 5 (outer shape equivalent points corresponding to the outer shape positions of the individual strands of the coil spring W) as strand data.

[0036] After step S2, the first movement control unit 333 operates the first movement device 6 to move the sensor 5 along the Z-axis at a specific speed (step S3). For example, the sensor 5 is positioned to measure the position of one upper end of the strands of a coil spring W installed on the support base 4, and as step S3 is performed, it moves downward at the specific speed. In this embodiment, the sensor 5 is moved from top to bottom, and the coating material is applied from one upper end to the other lower end of the strands of the coil spring W. However, conversely, the sensor 5 may be moved from bottom to top, and the coating material may be applied from the other lower end to the upper end of the strands of the coil spring W.

[0037] Here, the memory unit 32 stores data indicating the distance the sensor 5 moves along the Z-axis each time the support base 4 is rotated, for example, by 180°. Then, in step S3, the first movement control unit 333 reads this data from the memory unit 32 and moves the sensor 5 at a movement speed based on this data. Note that the value of the distance to be moved can be changed by user operation on the input unit 31.

[0038] After step S3, the target strand detection unit 334 detects the outer shape position of the target strand from among the outer shape positions of the coil spring W strands included in the strand data acquired in step S2 (step S4: target strand detection step).

[0039] Figure 5 is a flowchart of the target strand detection step (step S4). Figure 6 is a diagram illustrating the target strand detection step (step S4). Specifically, Figures 6(a) and 6(b) show the strand data, respectively. Also, in Figures 6(a) and 6(b), the solid lines L1 to L3 indicate the corresponding outline points for adjacent strands W1 to W3 of the coil spring W (located at different positions in the specific axis Ax direction) in the strand data. Here, the solid line L2 represents the corresponding outline point for the target strand W2. In Figures 6(a) and 6(b), the vertical axis is the first axis constituting the coordinate axis measured by the sensor 5 (hereinafter referred to as the sensor coordinate axis). The horizontal axis is the second axis constituting the sensor coordinate axis. Hereafter, in order to distinguish them from the sensor coordinate axis, the Y axis and Z axis will be referred to as the device coordinate axis. In this embodiment, as described above, the sensor 5 is installed to emit laser light in a line along the YZ plane from a direction tilted 45° with respect to the Y and Z axes. Therefore, the first axis (Z' axis) that points from the sensor 5 toward the object to be measured (corresponding to the direction of the laser light output from the sensor 5), and the second axis (Y' axis) perpendicular to the first axis, are rotated by 45° with respect to the Z and Y axes, respectively (see Figure 7). Figure 6(a) shows the case where there is no outline equivalent point on the virtual line VL passing through the search start position PS. Figure 6(b) shows the case where there is an outline equivalent point on the virtual line VL passing through the search start position PS.

[0040] In step S4, first, the target strand detection unit 334 sets a specific search start position PS (Figure 6) on the second axis Y' using the strand data acquired in step S2 (step S4A). Here, the control device 3 repeatedly executes the loop of steps S1 to S8. In the first loop of steps S1 to S8, the target strand detection unit 334 sets the center position of the measurement range of the sensor 5 on the second axis Y' as the search start position PS in step S4A. Note that the search start position PS is not limited to the center position of the measurement range of the sensor 5 on the second axis Y', but may be any other position on the second axis Y'. In the second and subsequent loops (next control cycles), the target strand detection unit 334 sets a specific position as the search start position PS in step S4A. Step S4A in the next control cycle will be explained later in the section titled "About Step S4A in the Next Control Cycle".

[0041] After step S4A, the target strand detection unit 334 refers to the strand data acquired in step S2 and starts a search process to extract outline-equivalent points located within a predetermined range on the virtual line VL (hereinafter referred to as the extraction range RE (Figure 6)) by sequentially moving a virtual line VL parallel to the first axis (Z' axis) from the search start position PS along the second axis (Y' axis) by a predetermined distance (hereinafter referred to as the virtual line movement pitch). Here, the virtual line movement pitch is a value determined by the measurement resolution of the sensor 5. The extraction range RE is a range determined by the installation positions of the sensor 5 and the coil spring W, and is a range on the first axis (Z' axis) where the strands of the coil spring W are expected to exist.

[0042] After step S4B, the target wire detection unit 334 continues the search process until it extracts a point corresponding to the outline (step S4C). If an outline equivalent point is extracted (Step S4C: Yes), the target strand detection unit 334 sets the outline equivalent point as the strand origin position and stores the position coordinates of the outline equivalent point in the storage unit 32 (Step S4D).

[0043] Specifically, in step S4D, the target strand detection unit 334 sets the strand origin position as shown below. First, let's consider the case where there are no points corresponding to the outline within the extraction range RE on the virtual line VL passing through the search starting position PS (Figure 6(a)). In this case, in step S4D, the target strand detection unit 334 sets the strand originating position as the outline equivalent point PA' extracted when the virtual line VL is moved with the smallest amount of movement from the search start position PS, among the outline equivalent point PA' extracted when the virtual line VL is moved in the first direction Ar1 along the second axis (Y' axis) from the search start position PS, and the outline equivalent point PB' extracted when the virtual line VL is moved in the second direction Ar2 opposite to the first direction Ar1 along the second axis (Y' axis).

[0044] Furthermore, we assume that the outline equivalent point PC' is located within the extraction range RE on the virtual line VL passing through the search start position PS (Figure 6(b)). In this case, the target strand detection unit 334 sets the outline equivalent point PC', which is within the extraction range RE on the virtual line VL passing through the search start position PS, as the strand origin position in step S4D.

[0045] After step S4D, the target wire detection unit 334 sets the search direction for moving the virtual wire VL (step S4E). Specifically, in step S4E, if there is no point corresponding to the outline within the extraction range RE on the virtual line VL passing through the search start position PS (Figure 6(a)), the target strand detection unit 334 sets the direction in which the virtual line VL was moved when finding the strand origin position from the search start position PS as the search direction. That is, in the case of Figure 6(a), the target strand detection unit 334 sets the first direction Ar1 as the search direction ArS.

[0046] On the other hand, if the target strand detection unit 334 finds an outline equivalent point PC' within the extraction range RE on the virtual line VL passing through the search start position PS (Figure 6(b)), in step S4E, it sets both directions Ar1 and Ar2 from the outline equivalent point PC' (strand origin position) as the search direction ArS.

[0047] After step S4E, the target strand detection unit 334 sets the direction in which it moves the virtual line VL from the strand origin position to the search direction ArS set in step S4E, and continues the search process until it is no longer possible to extract an outline equivalent point when the virtual line VL is moved by the virtual line movement pitch (step S4F).

[0048] If an outline equivalent point is extracted (step S4F: No), the target wire detection unit 334 determines whether the extracted outline equivalent point satisfies the continuity condition (step S4G). Here, the continuity condition is that the separation distance in the direction of the first axis (Z' axis) between it and the outline equivalent point extracted immediately before is less than or equal to a specific first threshold (for example, 1 mm).

[0049] If the continuity condition is determined to be met (step S4G: Yes), the target strand detection unit 334 stores the position coordinates of the outline equivalent point that the continuity condition was determined to be met in the storage unit 32, and returns to step S4F. On the other hand, if it is determined that the continuity condition is not met (step S4G: No), or if it is not possible to extract the outline equivalent point when the virtual line VL is moved by the virtual line movement pitch (step S4F: Yes), the target strand detection unit 334 terminates the search process (step S4H).

[0050] Through the steps S4A to S4H described above, the memory unit 32 stores the position coordinates of each outline equivalent point corresponding to the outline position of the target strand. In the example shown in Figure 6, the memory unit 32 stores the position coordinates of each outline equivalent point (including outline equivalent point PA') corresponding to the outline position of the target strand W2.

[0051] After step S4, the coating position calculation unit 335 calculates the position coordinates P2(y,z) of the coating material application position on the target strand based on the position coordinates of each outer shape equivalent point that corresponds to the outer shape position of the target strand detected in step S4 and stored in the storage unit 32 (step S5).

[0052] Figure 7 is a diagram illustrating step S5. Specifically, Figure 7 shows the emission region (YZ plane) of the line-shaped laser beam emitted from sensor 5. In Figure 7, the emission region of the laser beam is represented by dots. The Y' and Z' axes shown in Figure 7 are the sensor coordinate axes. Furthermore, the Y' and Z axes shown in Figure 7 are the device coordinate axes. Specifically, the coating position calculation unit 335 extracts position coordinates P01'(y01',z01') and P02'(y02',z02') from the position coordinates of each outline equivalent point corresponding to the outline position of the target strand detected in step S4 and stored in the storage unit 32. These position coordinates P01'(y01',z01') and P02'(y02',z02') are position coordinates on the sensor coordinate axis, and are the position coordinates of the two edges with high Z-axis coordinate values ​​on the part WR (represented by a thick line in Figure 7) that reflects the line-shaped laser light output from the sensor 5 on the target strand of the coil spring W. The coating position calculation unit 335 then calculates the midpoint of the position coordinates P01'(y01',z01') and P02'(y02',z02') of the two edges as the position coordinate P1'(y1',z1') of the coating position on the WR (Figure 7).

[0053] Next, the coating position calculation unit 335 converts the position coordinates P1'(y1',z1') on the sensor coordinate axis to position coordinates P1(y1,z1) on the device coordinate axis using the following equation (1). In equation (1), θ is an angle corresponding to the installation position of the sensor 5, and in this embodiment it is 45°.

[0054] (Math 1) y1 = y1'·cosθ - z1'·sinθ z1=y1´·sinθ+z1´·cosθ ···(1)

[0055] Finally, the coating position calculation unit 335 calculates position coordinates P2(y2,z2) by rotating position coordinates P1(y1,z1) by 180° around a specific axis Ax (Z axis), and calculates this position coordinate P2(y2,z2) as the coating position.

[0056] After step S5, the second movement control unit 336 operates the second movement device 8 to move the dispenser 7 to a position where the coating material is applied from the dispenser 7 to the application position (position coordinates P2(y2,z2)) (step S6).

[0057] After step S6, the coating device control unit 337 operates the dispenser 7 at a coating timing when the support base 4 has rotated 180° around a specific axis Ax from the measurement timing, and applies the coating material from the dispenser 7 to the coating position (position coordinates P2(y2,z2)) (step S7). This measurement timing is the timing at which the sensor 5 measured the outer shape position of the wires of the coil spring W in step S2.

[0058] After step S7, the second movement control unit 336 operates the second movement device 8 to move the dispenser 7 along the Z-axis at a specific movement speed (step S8). This specific movement speed is the same as the specific movement speed of the sensor 5 in step S3.

[0059] By repeatedly performing the above steps S1 to S8, the coating material is applied to the individual strands of the coil spring W from one end to the other.

[0060] [Regarding step S4A in the next control cycle] Figure 8 illustrates step S4A in the next control cycle. Specifically, Figure 8 corresponds to Figure 6. Figure 8(a) shows the completion time of step S4 in a predetermined control cycle. Figure 8(b) shows the start time of step S4 in the control cycle following the control cycle in Figure 8(a). In step S4A of the next control cycle after completing step S4 in a predetermined control cycle, the target strand detection unit 334 sets the search start position PS to the center position CP in the direction of the second axis (Y' axis) at the outer shape position of the target strand detected in step S4 of the predetermined control cycle. In this way, it continues to track the target strand that was initially detected.

[0061] According to the embodiment described above, the following effects are achieved. In the wire detection system according to this embodiment, the control device 3 rotates the support base 4 around a specific axis Ax. The control device 3 also operates the sensor 5 and acquires wire data from the sensor 5. Furthermore, the control device 3 detects the outer shape position of the target wire from among the outer shape positions of the coil spring W wires included in the wire data. More specifically, the control device 3 refers to the wire data and performs a search process to move a virtual line VL from the search start position PS along the second axis (Y' axis) and extract the outer shape equivalent points located on the virtual line VL, and detects a plurality of such outer shape equivalent points extracted consecutively by this search process as the outer shape position of the target wire. Therefore, even if the wire data includes multiple adjacent wires in the coil spring W (wires W1 to W3 in the example in Figure 6), the outer shape position of the target wire (wire W2 in the example in Figure 6) can be appropriately detected.

[0062] For example, in this embodiment, the wire data processing system is applied to a coating material application system 1 that applies a coating material to a coil spring W. The control device 3 calculates the application position of the coating material to the target wire based on the position coordinates of each outer shape equivalent point that corresponds to the outer shape position of the detected target wire. The control device 3 also moves the second moving device 8 to move the dispenser 7 to a position where the coating material will be applied from the dispenser 7 to the application position, and operates the dispenser 7 to apply the coating material from the dispenser 7 to the application position. Therefore, even if the wire data includes multiple adjacent wires in the coil spring W (wires W1 to W3 in the example in Figure 6), the coating material can be applied with high precision to the appropriate application position on the target wire (wire W2 in the example in Figure 6).

[0063] Furthermore, in this embodiment, the control device 3 detects multiple outline equivalent points as the outline position of the target strand, including the outline equivalent point extracted when the virtual line VL is moved with the smallest amount of movement from the search start position PS (outline equivalent point PA' in the example of Figure 6(a)), which is extracted when the virtual line VL is moved with the second axis (Y' axis) in the first direction Ar1 from the search start position PS (outline equivalent point PA' in the example of Figure 6(a)), and the outline equivalent point extracted when the virtual line VL is moved with the second axis (Y' axis) in the second direction Ar2 from the search start position PS (outline equivalent point PB' in the example of Figure 6(a)). Then, in the search process of the next control cycle after detecting the outline position of the target strand, the control device 3 sets the search start position PS to the center position CP in the direction of the second axis (Y' axis) at the outline position of the target strand. Therefore, the outer shape position of the target strand detected initially can be quickly detected in subsequent control cycles, and the strand can be continuously tracked.

[0064] By the way, as shown in Figure 6(a) with the dashed line L4 indicating wire W1, in some cases, adjacent wires W1 and W2 are measured overlapping in the wire data. In such cases, the outline equivalent point PD' corresponding to the outline position of wire W2 and the outline equivalent point PE' corresponding to the outline position of wire W1 are separated by a virtual line movement pitch in the direction of the second axis (Y' axis) and are located within the extraction range RE. As a result, the entire combination of wire W2 and wire W1, shown with the dashed line L4, is detected as the outline position of the target wire. In contrast, in this embodiment, the control device 3 performs step S4G to extract, by search processing, only those outline equivalent points PD', PE' that are adjacent in the direction of the second axis (Y' axis) (separated by a virtual line movement pitch in the direction of the second axis (Y' axis)) and whose separation distance in the direction of the first axis (Z' axis) is less than or equal to a specific first threshold. Therefore, the outer shape equivalent point PE' is not detected as the outer shape position of the target strand, and only strand W2 can be detected as the outer shape position of the target strand.

[0065] In this embodiment, the sensor 5 measures the outer shape position of the wires of the coil spring W from directions that intersect a specific axis Ax and a plane perpendicular to that specific axis Ax. Therefore, the outer shape position on the upper or lower side of the individual wires of the coil spring W can be accurately measured. In particular, when the sensor 5 is arranged in this manner, it is easy for adjacent strands W1 and W2 to be measured while overlapping, as described above. Therefore, by combining this arrangement of the sensor 5 with step S4G, it is possible to appropriately detect the outer shape position of the target strand while accurately detecting the outer shape position of the upper or lower surface of the target strand.

[0066] (Other embodiments) While embodiments for carrying out the present invention have been described so far, the present invention should not be limited to the embodiments described above. In the embodiments described above, the wire detection system according to the present invention was applied to the coating material application system 1, but the invention is not limited to this. For example, the wire detection system according to the present invention may be applied to a coil spring inspection system that, after detecting the outer shape position of a target wire, calculates the position coordinates and dimensions of a specific location corresponding to the outer shape position of the target wire, and then inspects the coil spring W. Furthermore, for example, the wire detection system according to the present invention may be applied to a coil spring processing system that, after detecting the outer shape position of a target wire, calculates the position coordinates of a specific location corresponding to the outer shape position of the target wire, and then performs processing on the coil spring W at the position coordinates of that location.

[0067] In the embodiment described above, the first moving device 6 moved the sensor 5 using only the Z axis, but it is not limited to this, and the sensor 5 may be configured to move in the Y axis and X axis directions as well as the Z axis. Similarly, the second moving device 8 moved the dispenser 7 using only the Z axis and Y axis, but it is not limited to this, and the dispenser 7 may be configured to move in the X axis direction as well as the Z axis and Y axis.

[0068] In the embodiment described above, the first moving device 6 moved the sensor 5 along the Z-axis relative to the coil spring W, but it is not limited to this, and the coil spring W (support base 4) may be moved along the Z-axis relative to the sensor 5. Furthermore, the first moving device 6 does not need to be provided if the measurement range of the sensor 5 extends over the entire coil spring W.

[0069] In the embodiment described above, the second movement control unit 336 operated the second movement device 8 to move the dispenser 7 to a position where the coating material was applied from the dispenser 7 to the application position (position coordinates P2(y2,z2)), but it is not limited to this. The second movement control unit 336 only needs to move the dispenser 7 and the support base 4 relative to each other to position the dispenser 7 at a position where the coating material is applied from the dispenser 7 to the application position (position coordinates P2(y2,z2)), and for example, the support base 4 may be moved relative to the dispenser 7.

[0070] In the embodiment described above, a laser sensor was used as sensor 5, but it is not limited to this. Any sensor that can measure the outer shape position of the wires of the coil spring W may be used, such as a camera or a TOF (Time Of Flight) sensor.

[0071] In step S4 according to the embodiment described above, step S4G does not need to be performed. That is, if the target strand detection unit 334 extracts a point corresponding to the outline (step S4F: No), it stores the position coordinates of the point corresponding to the outline in the storage unit 32 and returns to step S4F. Similarly, in the modified example 1 described later, step S4G does not need to be performed.

[0072] In the above-described embodiment, a support base 4 was used as the support mechanism according to the present invention. However, the invention is not limited to this, and other configurations may be used as long as they support the coil spring W and allow the coil spring W to rotate around a specific axis Ax that follows the central axis of the coil spring W. For example, the support mechanism according to the present invention may employ a robotic arm, and the coil spring W may be suspended by the robotic arm while the coil spring W is rotated around a specific axis that follows the central axis of the coil spring W. Furthermore, for example, as a support mechanism according to the present invention, a configuration may be adopted in which the coil spring W is supported in a position in which its central axis is oriented horizontally, and the coil spring W is rotated around a specific axis that follows the central axis.

[0073] In the embodiment described above, the following modified example 1 may also be adopted. Figure 9 illustrates a modified example of the embodiment. In the target strand detection step (step S4) according to this modified example 1, as shown in Figure 9, steps S4I and S4J are added to the target strand detection step (Figure 5) described in the above embodiment. Steps S4I and S4J will be mainly described below.

[0074] Step S4I is executed if it is determined that the continuity condition is not met (Step S4G: No), or if it is not possible to extract the outline equivalent point when the virtual line VL is moved by the virtual line movement pitch (Step S4F: Yes). Specifically, in step S4I, the target wire detection unit 334 determines whether each outline equivalent point extracted in the search process and stored in the storage unit 32 satisfies the non-noise condition. Here, the non-noise condition is that the number of outline equivalent points extracted in the search process and stored in the storage unit 32 exceeds a specific second threshold.

[0075] If the non-noise condition is not met (step S4I: No), that is, if the number of corresponding outline points extracted in the search process and stored in the memory unit 32 is less than or equal to a specific second threshold, the target strand detection unit 334 determines that each corresponding outline point is noise, changes the search start position PS (step S4J), and returns to step S4B. Then, the target strand detection unit 334 restarts the search process and detects the outline position of the target strand again.

[0076] On the other hand, if it is determined that the non-noise condition is met (step S4I: Yes), that is, if the number of outline equivalent points extracted in the search process and stored in the storage unit 32 exceeds a specific second threshold, the target strand detection unit 334 determines that each of the outline equivalent points is not noise and proceeds to step S4H.

[0077] According to the modified example 1 described above, in addition to the same effects as the embodiment described above, the following effects are achieved. In this modified example 1, if the number of points corresponding to each outline extracted in the search process and stored in the memory unit 32 is less than or equal to a specific second threshold, the control device 3 repeats the search process and detects the outline position of the target strand again. Therefore, by avoiding the extraction of noise contained in the strand data as equivalent outline points, the outline position of the target strand can be detected more appropriately.

[0078] In the embodiment described above, the following modified example 2 may also be adopted. Figure 10 illustrates a second modification of the embodiment. Specifically, Figure 10 corresponds to Figure 7. In this modified example 2, the cross-sectional shape of the wires of the coil spring W is "circular". In this modified example 2, the coating position calculation unit 335 then performs step S5 as shown below. Specifically, first, the coating position calculation unit 335 extracts the position coordinates P0'(y0',z0') and radius R from the position coordinates of each outline-equivalent point corresponding to the outline position of the target wire detected in step S4 and stored in the storage unit 32. The position coordinates P0'(y0',z0') are position coordinates on the sensor coordinate axis and are the position coordinates of the vertex of the part WA (represented by a thick line in Figure 10) on the wire of the coil spring W that reflects the line-shaped laser light output from the sensor 5. The radius R is the radius of the virtual circle containing part WA. Furthermore, the coating position calculation unit 335 calculates the position coordinates P1'(y1',z1') of the coating position on part WA using the following equation (2) based on the position coordinates P0'(y0',z0') and radius R. Note that the position coordinate P1'(y1',z1') is the position coordinate on the sensor coordinate axis, and is the position coordinate with the highest value in the Z-axis direction on the virtual circle containing part WA (Figure 10). Also, in equation (2), θ is the angle corresponding to the installation position of sensor 5, and in this modified example 2 it is 45°.

[0079] (Math 2) y1' = y0' - R·sinθ z1´=z0´-(RR·cosθ) ···(2)

[0080] Next, the coating position calculation unit 335 calculates the position coordinates P1(y1,z1) and P2(y2,z2) from the position coordinate P1'(y1',z1') calculated by equation (2), similar to the embodiment described above. [Explanation of Symbols]

[0081] 1. Coating material application system 2. Coating material application device 3. Control device 4 Support stand 5 sensors 6. First mobile device 7 Dispensers 8. Second mobile device 31 Input section 32 Storage section 33 Control Unit 61 Slider 62 Guide Rails 81 Slider 82,83 Guide rails 331 Support base control unit 332 Sensor Control Unit 333 First movement control unit 334 Target strand detection unit 335 Coating position calculation unit 336 Second movement control unit 337 Coating device control unit Ar1 First direction Ar2 Second direction ArS search direction Ax (Specific axis) CP center position L1~L3 Solid line L4 dashed line PA application position PA´~PE´ Outline equivalent point PM measurement position PS Search start position RE Extraction Range VL virtual line W coil spring W1~W3 Element wire WA,WR area

Claims

1. A support mechanism that supports a coil spring and allows the coil spring to rotate about a specific axis that follows the central axis of the coil spring, A sensor that measures the outer shape position of the wires of the coil spring and outputs wire data, The system comprises a control device that controls the operation of the support mechanism and the sensor, The control device is A support mechanism control unit that operates the support mechanism and rotates the coil spring about the specific axis, A sensor control unit that operates the aforementioned sensor and acquires the wire data from the sensor, The system includes a target wire detection unit that detects the outer shape position of a target wire among the outer shape positions of the wires of the coil spring included in the wire data, The aforementioned wire data is, The sensor coordinate axes include a first axis extending from the sensor toward the object to be measured, and a second axis perpendicular to the first axis, and include an outer shape equivalent point corresponding to the outer shape position of the wires of the coil spring measured by the sensor. The aforementioned target strand detection unit is A wire detection system that, by referring to the wire data, performs a search process to extract outline-equivalent points located on the virtual line that is parallel to the first axis, moving the virtual line parallel to the first axis along the second axis from a specific search start position on the second axis, and detects a plurality of outline-equivalent points successively extracted by the search process as the outline positions of the target wire.

2. The aforementioned target strand detection unit is The wire detection system according to claim 1, wherein the wire detection system detects the outline position of the target wire, including the plurality of outline equivalent points, which include the outline equivalent point extracted when the virtual line is moved with the smallest amount of movement from the search start position, among the outline equivalent points extracted when the virtual line is moved in a first direction along the second axis from the search start position and the outline equivalent points extracted when the virtual line is moved in a second direction opposite to the first direction along the second axis from the search start position.

3. The aforementioned target strand detection unit is The wire detection system according to claim 2, wherein the detection of the outer shape position of the target wire by the search process is repeatedly performed at a specific control cycle, and in the search process in the next control cycle after the detection of the outer shape position of the target wire, the second axial center position of the outer shape position of the target wire is set as the search start position.

4. The aforementioned target strand detection unit is The wire detection system according to claim 1, wherein the search process extracts only those outline equivalent points whose separation distance in the first axial direction between adjacent outline equivalent points in the second axial direction is less than or equal to a specific first threshold.

5. The aforementioned target strand detection unit is The wire detection system according to claim 1, wherein if the number of the plurality of outline equivalent points is less than or equal to a specific second threshold, the search process is repeated and the outline position of the target wire is detected again.

6. The device further comprises a coating apparatus for applying a coating material to the coil spring. The control device is A coating position calculation unit calculates the application position of the coating material to the target wire based on the outer shape position of the target wire, A movement control unit moves the coating device and the support mechanism relative to each other, and positions the coating device at a position where it applies the coating material to the coating position. The wire detection system according to claim 1, further comprising a coating device control unit that operates the coating device and causes the coating device to apply a coating material to the coating position.

7. The coating apparatus is further provided with a moving device for supporting the coating apparatus and moving the coating apparatus, The aforementioned movement control unit, The wire detection system according to claim 6, wherein the moving device is operated to position the coating device at a location where the coating material is applied to the coating position from the coating device.

8. The aforementioned sensor is The wire detection system according to claim 1, which measures the outer shape position of the wires of the coil spring from directions that intersect the specific axis and a plane perpendicular to the specific axis, respectively.

9. A support mechanism control unit operates a support mechanism that supports a coil spring and rotates the coil spring about a specific axis that follows the central axis of the coil spring, A sensor operates a sensor that measures the outer shape position of the wires of the coil spring and outputs wire data, and a sensor control unit acquires the wire data. The system includes a target wire detection unit that detects the outer shape position of a target wire among the outer shape positions of the wires of the coil spring included in the wire data, The aforementioned wire data is, The sensor coordinate axes include a first axis extending from the sensor toward the object to be measured, and a second axis perpendicular to the first axis, and include an outer shape equivalent point corresponding to the outer shape position of the wires of the coil spring measured by the sensor. The aforementioned target strand detection unit is A control device that, by referring to the aforementioned strand data, performs a search process to extract outline-equivalent points located on the second axis by moving a virtual line parallel to the first axis along the second axis from a specific search start position on the second axis, and detects a plurality of outline-equivalent points successively extracted by the search process as the outline positions of the target strand.

10. A control method performed by a control device of a wire detection system, A support mechanism control step involves operating a support mechanism that supports a coil spring and rotating the coil spring about a specific axis that follows the central axis of the coil spring, A sensor control step involves operating a sensor that measures the outer shape position of the wires of the coil spring and outputs wire data, and acquiring the wire data. The process includes a target wire detection step for detecting the outer shape position of a target wire among the outer shape positions of the wires of the coil spring included in the wire data, The aforementioned wire data is, The sensor coordinate axes include a first axis extending from the sensor toward the object to be measured, and a second axis perpendicular to the first axis, and include an outer shape equivalent point corresponding to the outer shape position of the wires of the coil spring measured by the sensor. In the aforementioned target wire detection step, A control method that, by referring to the aforementioned strand data, performs a search process to move a virtual line parallel to the first axis along the second axis from a specific search start position on the second axis to extract outline-equivalent points located on the virtual line, and detects a plurality of outline-equivalent points successively extracted by the search process as the outline position of the target strand.

11. A support mechanism control step involves operating a support mechanism that supports a coil spring and rotating the coil spring about a specific axis that follows the central axis of the coil spring, A sensor control step involves operating a sensor that measures the outer shape position of the wires of the coil spring and outputs wire data, and acquiring the wire data. The computer is instructed to perform a target wire detection step, which involves detecting the outer shape position of a target wire among the outer shape positions of the coil spring wires included in the wire data, The aforementioned wire data is, The sensor coordinate axes include a first axis extending from the sensor toward the object to be measured, and a second axis perpendicular to the first axis, and include an outer shape equivalent point corresponding to the outer shape position of the wires of the coil spring measured by the sensor. In the aforementioned target wire detection step, A control program that, by referring to the aforementioned strand data, performs a search process to extract outline-equivalent points located on the second axis by moving a virtual line parallel to the first axis along the second axis from a specific search start position on the second axis, and detects a plurality of outline-equivalent points successively extracted by the search process as the outline positions of the target strand.

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