JP4180459B2 - Unequal pitch spring direction detection device - Google Patents

Description

  The present invention relates to a direction discriminating device for unequal pitch springs.

  An unequal pitch spring having a dense pitch on one end and a coarse pitch on the other end is employed in a valve opening / closing mechanism of an automobile engine. The unequal pitch spring having such directionality is coated with a marker serving as a mark at either one end, but the direction of the unequal pitch spring is automatically determined before the coating process, There is a step of aligning in a certain direction.

  Conventionally, the automatic discrimination of the direction of the unequal pitch spring has been performed by detecting the difference in the pitch interval between the densely wound portion and the coarsely wound portion of the unequal pitch spring using an optical sensor or a vortex sensor (for example, (See Patent Document 1 and Patent Document 2).

Japanese Patent No. 3136216 (paragraphs [0011] to [0017], FIG. 1)

Japanese Patent Laid-Open No. 10-38505 (paragraphs [0015] to [0016], FIG. 2)

  However, the discrimination means described above is effective when the difference between the pitch in the densely wound portion of the unequal pitch spring and the pitch in the coarsely wound portion is relatively large, but the difference is so large that the pitch difference cannot be confirmed visually. If it is small, it is difficult to determine the direction. Further, when there is a variation in pitch interval, for example, even in the case of a densely wound portion, there is a possibility that the densely wound portion may be mistakenly identified as a coarsely wound portion if a portion having a relatively wide pitch interval is measured.

  Therefore, an object of the present invention is to provide a direction discriminating device that reliably identifies the direction of an unequal pitch spring.

  In order to achieve the above object, the unequal pitch spring direction discriminating apparatus according to the present invention is any one of the unequal pitch springs in which a coarsely wound portion is formed on one end side and a densely wound portion is formed on the other end side. Imaging means for imaging one end face from the axial direction, extraction means for extracting the end portion of the unequal pitch spring from the taken end face, and the extracted end part shape as a regular winding part or a regular winding part Comparing with the shape of the terminal portion, the calculation means for calculating the degree of correlation between the two is provided, and the direction of the unequal pitch springs is determined based on the calculation result of the calculation means (claim 1).

  The present invention pays attention to the fact that the end portions of the coarsely wound portion and the densely wound portion of the unequal pitch spring each have a unique shape, and the shape of the end portion of the unequal pitch spring is the shape of the regular end portion based on the above configuration. Since the direction is discriminated by evaluating the degree of correlation by comparison with, the pitch difference between the densely wound portion and the coarsely wound portion of the unequal pitch spring is small, or the pitch interval varies. Even if it exists, the direction can be determined reliably.

  In addition, the unequal pitch spring direction discriminating apparatus according to the present invention is inclined obliquely with respect to the transport direction of the transport line at a predetermined position of the transport line for continuously transporting the unequal pitch spring in a vertical state. The guide plate is disposed slightly above the conveyance line, and the imaging means is disposed at a predetermined position above the guide plate.

  As a result, the direction of the unequal pitch springs can be quickly determined for all the numbers in-line. Further, since the inspection is performed on the existing conveyance line, the inspection can be performed without providing a new inspection space.

  The unequal pitch spring direction discriminating apparatus according to the present invention includes a sorting plate rotatably connected to a downstream end portion of the guide plate on the conveying line, and the sorting plate based on a computation result of the computing means. The selecting means including the driving means for opening and closing the guide plate is disposed on the downstream side of the conveying line of the guide plate (claim 3).

  The sorting means discriminates the direction of the unequal pitch spring based on the calculation result of the calculation means, and then drives the driving means based on the discrimination result to open and close the sorting plate. Based on the determination result, sorting can be performed on the transport line.

  Next, the principle of the discriminating operation of the unequal pitch spring direction discriminating device according to the present invention will be described with reference to FIGS.

  The unequal pitch spring is formed into a spiral coil spring through the following coiling process. In this step, as shown in FIG. 6 (a), a linear unequal pitch spring material 2A is supplied to a cored bar 11 having a semicircular cross section through a guide 12, and the unequal pitch spring material 2A is fed into the core. While being held by the gold 11 and the coiling pin 13 (two places in this example), the core 11 is fed in the direction of the arrow A by the pair of feed rollers 14, and the core 11 and the coiling pin are set with the center O of the core 11 as the rotation center. 13 is rotated by a predetermined number of turns. Meanwhile, by moving the metal core 11 and the coiling pin 13 in the axial direction at a moving speed corresponding to a predetermined pitch, the unequal pitch springs 2 having different pitches at both ends are formed. After rotating a predetermined number of turns, the rotation of the cored bar 11 and the coiling pin 13 is stopped, and the cutter 15 is moved relative to the cored bar 11 (in the direction of arrow B). Cut (see FIG. 6B).

  At this time, since the cutter 15 moves along the diameter line of the core metal 11 having a semicircular cross section and cuts the unequal pitch spring material 2A, the cutter 15 is not supported by one of the cut ends, that is, the core metal 11. The terminal portion 2a on the winding end side of the equal pitch spring 2 becomes a non-linear complicated cut end (see FIG. 7A). On the other hand, the other cut end is supported by the cored bar 11 at the time of cutting, so that the terminal portion 2b on the winding start side is against the diameter surface 11a passing through the center O of the cored bar 11. It becomes a substantially parallel straight cut (see FIG. 7B).

  In this way, the shape of the terminal portion (cut end) is different between the winding start side and the winding end side, and depending on the setting of the coiling machine, for example, the winding start side is a dense winding portion and the winding end side is a rough winding. Determined by the part. This indicates that if the shape of the terminal portion is viewed, it can be easily determined whether the end portion including the terminal portion is the densely wound portion side or the coarsely wound portion side. This was used as a reference for discriminating the direction of unequal pitch springs. Therefore, if the direction is determined according to the above-described determination criteria, the direction of the unequal pitch springs can be determined even when the pitch difference between the densely wound portion and the coarsely wound portion is small or the pitch interval varies. The determination can be made reliably and easily.

  As described above, according to the unequal pitch spring direction discriminating apparatus according to the present invention, the pitch difference between the densely wound portion and the coarsely wound portion of the unequal pitch spring is small, or the pitch interval varies. However, the direction can be reliably determined. In addition, by performing this direction discriminating means on an existing line, it is possible to carry out a discrimination inspection continuously and quickly for all unequal pitch spring directions on the transport line.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. This embodiment also serves as an automatic measuring device for the perpendicularity of the spring.

  As shown in FIG. 1, the unequal pitch spring direction discriminating device 1 includes an image recognition device 3, a first guide plate 4, and a laser position sensor 5 as main elements.

  As shown in FIG. 1, the image recognition device 3 is arranged above the unequal pitch spring 2 located on the transport line 6 and is a CCD camera 7 as an imaging means for imaging the upper end winding surface of the unequal pitch spring 2. The ring light 9 that uniformly irradiates the upper end winding surface of the unequal pitch spring 2 imaged by the CCD camera 7 from above the unequal pitch spring 2 and the CCD camera 7 The controller 8 is configured to determine the direction of the unequal pitch spring 2 and measure the squareness based on the image, and the display device 10 (see FIG. 2) that displays the processing result of the controller 8.

  As shown in FIG. 2, the controller 8 extracts extraction means for extracting the end portion of the upper end wound surface of the unequal pitch spring 2 from the image taken by the CCD camera 7 in order to determine the direction of the unequal pitch spring 2. The first extraction unit 8a1 as the first calculation unit, and the shape of the terminal unit extracted by the first extraction unit 8a1 is compared with the normal shape of the unequal pitch spring 2 terminal unit to calculate the degree of correlation between them. One calculation unit 8b1 and a first determination unit 8c1 for determining the direction of the unequal pitch spring 2 based on the calculation result of the first calculation unit 8b1.

  Furthermore, the controller 8 measures the perpendicularity of the spring, the second extraction unit 8a2 for extracting the upper end circling surface from the image captured by the CCD camera 7, and the non-extraction extracted by the second extraction unit 8a2. The center of the upper end winding surface of the equal pitch spring 2 is calculated, and the lower end seat of the unequal pitch spring 2 is calculated based on the positions of both ends in the diameter direction of the lower end portion of the unequal pitch spring 2 detected by a laser position sensor 5 described later. A second calculation unit 8b2 for calculating the center of the winding surface; and a second determination unit 8c2 for calculating the squareness of the unequal pitch spring 2 based on the calculation result of the second calculation unit 8b2 and determining the quality. Is. In addition, the squareness in the text means an inclination angle of the axis of the unequal pitch spring 2 with respect to a vertical line perpendicular to the end winding surface of the unequal pitch spring 2.

  The first guide plate 4 is lifted slightly above the transfer line 6 using an appropriate support member, and is inclined with respect to the transfer direction of the transfer line 6 (see FIG. 1). Fixed to the base surface. The height of the first guide plate 4 is such that the first guide plate 4 and the lower end of the unequal pitch spring 2 are in contact with each other and the unequal pitch spring 2 is upright. It is preferable to set it to such an extent that it is aligned along.

  A first sorting device 16 is disposed on the downstream side of the conveying line 6 of the first guide plate 4, and a second sorting device 20 is further disposed on the downstream side thereof. As shown in FIG. 4, the first sorting device 16 and the second sorting device 20 include a first cylinder 17 and a second cylinder that are rotatably supported by the first stationary side basic surface 25 and the second stationary side basic surface 26. 21, first cylinder 17, first piston rod 18, second piston rod 22, which is slidably held in the longitudinal direction of second cylinder 21, and projecting ends of first piston rod 18 and second piston rod 22 The first guide plate 4 and the second guide plate 23 are rotatably connected to the downstream end portions of the first guide plate 4 and the second guide plate 23 via the first connection member 19 and the second connection member 24. It comprises a first sorting plate 4a and a second sorting plate 23a. The first sorting device 16 and the second sorting device 20 receive the signal transmitted from the controller 8 based on the result determined by the controller 8 and cause the first piston rod 18 and the second piston rod 22 to expand and contract. The first sorting plate 4a and the second sorting plate 23a are opened and closed.

  The laser position sensor 5 has an appropriate support member so that the longitudinal direction of the first guide plate 4 arranged as described above and the beam 5a irradiated from the laser position sensor 5 are orthogonal to each other (see FIG. 3). It is installed in a state slightly spaced upward from the transport line 6 or outside the transport line 6. The laser position sensor 5 detects the positions of both ends in the diameter direction of the lower end portion of the unequal pitch spring 2 when the coordinate axis is taken in the longitudinal direction of the guide plate 4.

  As described above, the unequal pitch spring direction discriminating apparatus 1 according to the present embodiment measures the perpendicularity of the unequal pitch spring 2 in addition to the components for carrying out the unequal pitch spring 2 direction discrimination. It also has the following elements. Accordingly, in this embodiment, the direction determination of the unequal pitch spring 2 and the measurement of the perpendicularity of the unequal pitch spring 2 are performed simultaneously. Each operation will be described in the order of the squareness measurement.

  The operation of discriminating the direction of the unequal pitch spring 2 using the unequal pitch spring direction discriminating device 1 having the above-described configuration will be described below.

  6 (a) and 6 (b), the unequal pitch spring 2 coiled in a predetermined shape and subjected to a predetermined heat treatment and shot peening process is continuously mounted in an upright state on the upstream side of the transfer line 6. Put. These unequal pitch springs 2 are conveyed by the conveyance line 6 in the direction of the broken line arrow A as shown in FIG. 3 and then contact the first guide plate 4. The unequal pitch spring 2 changes its moving direction by the guide plate 4 and moves in the direction of a broken line arrow B.

  Thus, when the unequal pitch springs 2, 2,... That have moved along the first guide plate 4 move to the position of the dotted line in FIG. 3, the laser position sensor 5 detects the position information. When a trigger signal is transmitted from the laser position sensor 5 to the controller 8, the CCD camera 7 receives the trigger signal and images the upper end winding surface of the unequal pitch spring 2.

  Next, the first extraction unit 8a1 provided in the controller 8 extracts the terminal portion of the unequal pitch spring 2 from the image captured by the CCD camera 7, and the first calculation unit 8b1 extracts by the first extraction unit 8a1. The shape of the terminal portion thus compared with the normal shape of the terminal portion of the coarsely wound portion or the densely wound portion registered in advance (see 2a and 2b in FIGS. 7A and 7B) and the degree of correlation between the two Is calculated.

  At this time, the first determination unit 8c1 has, for example, a correlation degree between the shape of the terminal portion extracted by the first extraction unit 8a1 and the normal shape of the coarse winding side terminal portion is larger than that on the dense winding side, and When the predetermined correlation degree (threshold value) is exceeded, it is determined that the upper end portion of the unequal pitch spring 2 is a coarsely wound portion. On the contrary, the degree of correlation between the shape of the terminal part extracted by the first extraction unit 8a1 and the normal shape of the densely wound part side terminal part is larger than that of the coarsely wound part side, and a predetermined correlation (threshold) is set. When exceeding, it determines with the upper end part of the unequal pitch spring 2 being a close winding part.

  In rare cases, when neither of the above cases is applicable, it is determined that the unequal pitch spring 2 is a defective cutting product during coiling.

  Next, the operation of the perpendicularity measurement of the unequal pitch spring 2 using the unequal pitch spring direction discriminating apparatus 1 having the above-described configuration will be described.

  As described above, when the unequal pitch spring 2 moves to the position of the dotted line portion in FIG. 3, the laser position sensor 5 detects the lower end portion of the unequal pitch spring 2 when the longitudinal direction of the first guide plate 4 is taken as the coordinate axis. Detect the positions of both ends in the diameter direction. At this time, the second calculation unit 8b2 is in contact with the lower end portion of the unequal pitch spring 2 and the first guide plate 4 and from the both end positions of the lower end portion of the unequal pitch spring 2 detected by the laser position sensor 5. The center 2f (see FIG. 5) of the lower end winding surface 2d of the unequal pitch spring 2 is determined.

  When the laser position sensor 5 detects the positions of both ends in the diameter direction of the lower end portion of the unequal pitch spring 2, a trigger signal is transmitted from the laser position sensor 5 to the controller 8, and the CCD camera 7 detects the upper end of the unequal pitch spring 2. Image the end face. Thereafter, the second extraction unit 8a2 extracts the upper end winding surface 2c of the unequal pitch spring 2 from the image captured by the CCD camera 7, and the second calculation unit 8b2 extracts the upper end seat extracted by the second extraction unit 8a2. The center 2e (see FIG. 5) of the winding surface 2c is calculated.

  Next, as shown in FIG. 5, the second determination unit 8 c 2 has the center 2 e of the upper end wound surface 2 c and the center of the lower end wound surface 2 d when the unequal pitch spring 2 is viewed from the imaging direction of the CCD camera 7. The horizontal distance δ between 2f is calculated, and the squareness of the unequal pitch spring 2 is calculated from the ratio of the horizontal distance δ and the free height λ of the unequal pitch spring 2. At this time, if the calculated squareness is equal to or less than the reference value (threshold value), it is determined that the squareness is good, and if the calculated squareness exceeds the reference value (threshold value), it is determined to be defective.

  As described above, as a result of the direction determination and the squareness measurement of the unequal pitch springs 2, each unequal pitch spring 2 is transported to the next process based on the determination result. For example, in the case of the unequal pitch spring 2 in which the first determination unit 8c1 determines that the upper end portion is a rough winding portion and the second determination unit 8c2 determines that the squareness is good, the first determination unit 8c1 The second determination unit 8c2 transmits a signal based on the determination result to the first sorting device 16, and the first sorting device 16 that has received the signal extends the first piston rod 18, and the first sorting plate 4a. (Closed line position in FIG. 4). Thereby, the said unequal pitch spring 2 is conveyed to the following coating process (line of the arrow A of FIG. 4).

  On the other hand, in the case of the unequal pitch spring 2 in which the first determination unit 8c1 determines that the upper end is a closely wound portion and the second determination unit 8c2 determines that the squareness is good. The determination unit 8c1 and the second determination unit 8c2 transmit a signal based on the determination result to the first sorting device 16, and the first sorting device 16 that has received the signal contracts the first piston rod 18 to perform the first sorting. Open the plate 4a (the position of the dashed line in FIG. 4). As a result, the unequal pitch springs 2 are transported on the transport line 6 along the first sorting plate 4 a and come into contact with the second guide plate 23 of the second sorting device 20 installed on the downstream side of the transport line 6. . Further, the second sorting device 20 contracts the second piston rod 22 on the basis of signals received from the first judgment unit 8c1 and the second judgment unit 8c2, and opens the second sorting plate 23a (one point in FIG. 4). The position of the chain line), the unequal pitch spring 2 is conveyed to the vertical reversing process (line B in FIG. 4).

  Note that if it is determined that the cutting is defective in the direction determination, or if it is determined that the perpendicularity is defective, first, the first sorting device is based on signals sent from the first determination unit 8c1 and the second determination unit 8c2. 16 opens the first sorting plate 4a (the position of the chain line in FIG. 4). Next, the second sorting device 20 closes the second sorting plate 23a on the basis of the signals received from the first judging unit 8c1 and the second judging unit 8c2 (the position indicated by the solid line in FIG. 4), so that (c) The unequal pitch springs 2 are conveyed on the line indicated by arrow C in FIG. 4 and discarded.

  In the above-described embodiment, the case where the direction determination of the unequal pitch spring 2 and the perpendicularity measurement are performed simultaneously and in a short time has been described, but of course, only the direction determination may be performed. Further, in the present embodiment, the case where the direction determination and the perpendicularity measurement are performed with the unequal pitch spring 2 standing upright is shown, but the present invention can be implemented even when the unequal pitch spring 2 is laid sideways. It is. In this case, for example, the CCD camera 7 is installed so that the imaging direction thereof is orthogonal to any one of the winding surfaces of the unequal pitch spring 2, and the laser position sensor 5 is provided with the beam 5a of the unequal pitch spring 2. Two beams 5a may be provided so that the beam 5a passes through the remaining one end of the unequal pitch spring 2.

  In the present embodiment, the first guide plate 4 and the laser position sensor 5 are slightly moved from the transport line 6 using an appropriate support member so that the longitudinal direction of the first guide plate 4 and the axial direction of the laser position sensor 5 are orthogonal to each other. However, the present invention is not limited to this configuration. For example, a laser position sensor is used in place of the first guide plate 4, and a beam from the laser position sensor and an existing laser are installed. Another new unit can be provided so that the beam 5a from the position sensor 5 is orthogonal. In addition, a jig for moving the unequal pitch spring 2 from the previous process line to a predetermined inspection position and a moving mechanism thereof may be provided while holding the unequal pitch spring 2 by chucking or the like. .

It is a front view which shows an example of embodiment of the direction discrimination | determination apparatus 1 of the unequal pitch spring concerning this invention. It is a figure which shows the processing element which comprises the controller 8 of the said unequal pitch spring direction discriminating device. It is a top view which shows an example of embodiment of the direction discrimination | determination apparatus 1 of the said unequal pitch spring. 3 is a plan view of a first sorting device 16 and a second sorting device 20 that sort unequal pitch springs 2 based on a determination result by the controller 8. FIG. 4 is a plan view of the unequal pitch spring 2 when the unequal pitch spring 2 is viewed from the imaging direction of the CCD camera 7. FIG. 5 is a plan view conceptually showing a coiling process of the unequal pitch spring 2. FIG. It is a top view which shows the terminal parts 2a and 2b of the rough winding part or dense winding part of the unequal pitch spring 2, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Unequal pitch spring direction discriminating device 2 Unequal pitch spring 2A Unequal pitch spring material 2a End portion 2b of unequal pitch spring winding end portion 3b Unequal pitch spring winding end portion 3 Image recognition device 4 One guide plate 4a First sorting plate 5 Laser position sensor 6 Conveying line 7 CCD camera 8 Controller 11 Core bar 13 Coiling pin 15 Cutter 16 First sorting device 20 Second sorting device 23 Second guide plate 23a Second sorting plate

Claims (3)

From an image pickup means for picking up an image of one end winding surface of an unequal pitch spring in which a coarse winding portion is formed on one end side and a dense winding portion is formed on the other end side, from the imaged end winding surface Extracting means for extracting the terminal portion of the unequal pitch spring, comprising a calculating means for calculating the degree of correlation between the extracted terminal portion shape by comparing it with the regular terminal shape of the coarsely wound portion or the densely wound portion, An unequal pitch spring direction discriminating apparatus characterized in that the direction of an unequal pitch spring is discriminated based on a calculation result of a calculation means. A guide plate that is inclined obliquely with respect to the transport direction of the transport line is disposed at a predetermined position on the transport line that continuously transports the unequal pitch springs in a vertically standing state, spaced slightly above the transport line. The unequal pitch spring direction discriminating apparatus according to claim 1, wherein the imaging means is disposed at a predetermined position above the guide plate. Sorting means comprising a sorting plate that is rotatably connected to the downstream end of the guide plate on the conveying line, and driving means that opens and closes the sorting plate with respect to the guide plate based on the computation result of the computing means, The unequal pitch spring direction discriminating device according to claim 2, wherein the unequal pitch spring direction discriminating device is disposed downstream of the guide plate on a conveying line.

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