JPH0569611U - Rotation detector - Google Patents

Abstract

(57) [Abstract] [Purpose] The shape of the work and the form of the transfer device are not limited,
(EN) Provided is a rotation detecting device capable of reliably guaranteeing that a work has rotated by a predetermined rotation amount. [Structure] The work 1 is rotated by receiving a rotational force from a drive means 20. The holding means 30 cantileverly holds one end of the work 1 in a direction along the rotation center line of the work 1. The holding means 30 rotates together with the work 1. The rotation amount detecting means 40 detects the rotation amount of the holding means.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a rotation detection device for detecting whether or not a work is properly rotated, for example, when performing a visual inspection on the entire circumference of a work by rotating the work with respect to a visual inspection device fixed at a fixed position. It is about.

[0002]

[Prior Art]

 Conventionally, when performing a visual inspection for scratches and stains on the inside and outside of the bottle, by fixing the TV camera as a visual sensor of the visual inspection device that captures information on the external appearance of the bottle in a fixed position, and rotating the bottle. A device that captures information about the entire circumference of the bottle with a TV camera is being considered. Further, in this type of apparatus, since bottles as works are usually conveyed one after another, it is required to guarantee that the works make one rotation within the field of view of the TV camera.

In order to meet such a requirement, as shown in FIG. 12, a pedestal 51 on which the work 1 is placed and a pressing body 52 having a variable distance from the pedestal 51 are provided, and a center line of rotation is provided. A device in which the work 1 is sandwiched between the pedestal 51 and the pressing body 52 in the direction along is considered. In this device, since the work 1 is clamped from both sides, the work 1 does not slip on the pedestal 51 and the pressing body 52, and if the pedestal 51 or the pressing body 52 can be rotated once, the work 1 Is guaranteed to rotate once. However, this apparatus has a problem that the upper and lower surfaces of the work 1 are required to be parallel, and the shape of the work 1 is limited.

On the other hand, as shown in FIG. 13, one end of the work 1 in the direction along the center line of rotation is cantilevered by using a holding means 30 such as a vacuum suction pad, or as shown in FIG. As shown, it is considered to hold a part of the work 1 by using two belts 54 that move in mutually opposite directions. In these devices, slippage may occur relatively between the holding means 30 and the belt 54 and the work 1, so it is necessary to detect the rotation amount of the work 1. As a method of detecting the rotation amount of the work 1, the mark 55 is provided on the peripheral surface (the surface along the rotation center line) or the bottom surface (the surface orthogonal to the rotation center line) of the work 1, and the mark 55 A method of detecting the position with a visual inspection device is being considered. However, it is necessary to add the mark 55 to the work 1, which causes a problem of cost increase. Further, in the configuration shown in FIG. 14, the cross section orthogonal to the rotation center line of the work 1 is required to be circular, which limits the shape of the work 1.

Further, it has been considered to detect the rotation amount of the work 1 by using the Doppler effect of light or sound waves. In this type of device, it is not necessary to give the mark 55 to the work 1, but when the work 1 is rotating and revolving, it is determined whether the Doppler effect is caused by the rotation or the revolution. It is difficult to identify, and there is a problem that a device for transporting the work 1 is limited.

There is no limitation on the shape of the work 1, there is no need to provide the mark 15 on the work 1, and there is no limitation on the transfer device of the work 1, while the work 1 is in the visual field of the appearance inspection device. The device shown in FIG. 15 is also considered for the purpose of guaranteeing one rotation. That is, the vacuum suction pad 31 is used as the holding means 30 to hold one end of the workpiece 1 in the direction along the center line of rotation, and the pressure sensor 56 provided in the vacuum suction path of the vacuum suction pad 31 changes the pressure. By detecting, it is intended to guarantee that the work 1 has rotated once. That is, if the pressure sensor 56 does not detect a decrease in the degree of vacuum, it is considered that the holding means 30 holds the work 1 with sufficient holding force, and the work 1 rotates with respect to the holding means 30 without slipping. It is determined that there is. In this configuration, since the work 1 is held in a cantilever manner, the shape of the work 1 is not limited, and since the rotation of the work 1 is guaranteed by the pressure sensor 56, it is not necessary to attach the mark 55 to the work 1. Moreover, the structure is applicable even when the work 1 revolves around its own axis.

[0007]

However, in the configuration shown in FIG. 15, the rotation amount of the work 1 is not actually detected, and the holding means 30 and the work 1 are not detected based on the pressure change of the vacuum system. There is a problem in that it is not completely guaranteed whether or not the work 1 has made one revolution within the visual field of the visual inspection apparatus because it is only determined that there is no slippage between the two.

The present invention is intended to solve the above-mentioned problems, and there is no limitation on the shape of the work or the form of the transfer device, and moreover, it is possible to reliably ensure that the work has rotated by a predetermined rotation amount. It is intended to provide the rotation detecting device.

[0009]

[Means for Solving the Problems]

 According to the present invention, in order to achieve the above object, a drive means for transmitting a rotational force to a work, a holding means for holding one end of the work in a direction along a rotation center line and rotating with the work, and a holding means The rotation amount detecting means for detecting the rotation amount is provided.

[0010]

[Action]

 According to the above configuration, since the holding means holds one end of the work in the direction along the center line of rotation, the work is held in a cantilevered manner, and there is almost no restriction on the shape of the work. There is no. Further, since the work is rotated by the drive means so that the holding means is rotated by receiving the rotational force from the work and the rotation amount of the holding means is detected by the rotation amount detecting means, the rotation amount of the work is detected by the rotation amount detecting means. Therefore, it is guaranteed that the rotation amount is equal to or more than the detected rotation amount, and if the rotation amount detected by the rotation amount detection means is 1 rotation or more, the work is surely guaranteed to be rotated 1 rotation or more. You can do it. Moreover, since the rotation amount of the transfer device is detected, it is not necessary to add a mark to the work, and a transfer device in which the work revolves along with its rotation can be used.

[0011]

【Example】

 Example 1 FIG. 1 shows the overall configuration of the present invention. In this embodiment, a bottle is exemplified as the work 1, but the shape of the work 1 is not particularly limited, and the technical idea of the present invention can be applied to any work 1 that needs to be rotated.

As shown in FIG. 2, the bottle 1 is introduced from the line 11 to the star wheel 13 by the guide wheel 12a, revolves around the circumference of the star wheel 13, and then is guided by the guide wheel 12b to be a good product and a defective product. And are sent to the lines 11a and 11b. The guide wheels 12a and 12b and the star wheel 13 are provided on the frame 10 as shown in FIG. An illumination device 14 and a TV camera 15 as a visual sensor of the appearance inspection device are arranged on the pedestal 10 so as to face each other, and the appearance of the bottle 1 located in the visual field VF of the TV camera 15 on the star wheel 13 can be viewed as a TV camera. The image is picked up at LA 15. Further, in the field of view VF of the TV camera 15, the bottle 1 rotates and makes one rotation.

The driving means 20 for rotating the bottle 1 has a structure as shown in FIGS. 4 and 5. That is, the drive means 20 is provided with a cylindrical rotary base 22 having a friction member 21 such as rubber, which contacts the peripheral portion of the bottom surface of the bottle 1, on the upper end surface. A gear unit 23 is provided at the lower end of the rotary table 22, and a gear 24 meshes with the gear unit 23. The gear 24 is coaxially coupled to the intermediate pulley 25, and the rotary base 22 is rotated by transmitting the rotational force from the drive source to the intermediate pulley 25. The intermediate pulley 25 is coupled to the rotation transmission bar 26 so as to convert the linear movement transmitted from the drive source 27, which is a linear solenoid, through the rotation transmission bar 26 into rotational movement. The drive source 27 is provided with a return spring 28. Although the linear drive type is used as the drive source 27, a rotary type such as a motor may be used to rotate the intermediate pulley 25. In this way, when the turntable 22 is rotated, the bottle 1 frictionally coupled through the friction member 21 rotates. Here, the bottle 1 is supported by the guide roller 16 so as not to tilt. The upper and lower intermediate portions of the rotary table 22 are rotatably supported by a cylindrical bearing 17 provided on the star wheel 13 via a bearing 18.

A rotary tube 32 having a vacuum suction pad 31 for attracting the bottom surface of the bottle 1 at its tip portion is inserted through the center of the turntable 22. Both upper and lower ends of the rotary tube 32 are rotatably supported by the rotary table 22 via bearings 33. The lower end of the rotary tube 32 is connected to a suction tube 33 fixed at a fixed position via a rotary joint 34 such as a ball joint, so that the rotary tube 32 can freely rotate with respect to the suction tube 33. You can move. The vacuum suction pad 31 adsorbs the bottom surface of the bottle 1 by discharging the internal air through the rotary tube 32 and the suction tube 33. That is, the vacuum suction pad 31, the rotary tube 32, and the suction tube 33 constitute a holding means 30 for holding the bottle 1 in a cantilever manner. In this way, when the bottle 1 is sucked by the vacuum suction pad 31, the bottle 1 receives a tensile force toward the rotary table 22, and the frictional force between the bottle 1 and the friction member 21 increases, The rotating force from the turntable 22 can be reliably transmitted to the bottle 1.

At the lower end of the rotary tube 32, a rotation amount detecting means 40 for detecting the rotation amount of the rotary tube 32 is provided. As the rotation amount detecting means 40, for example, as shown in FIG. 6 (a), a chopper plate 42 having a large number of notches 41 formed at equal circumferential intervals is provided on the peripheral part, and as shown in FIG. 6 (b), the chopper plate 42 is provided. It is possible to use a structure in which a sensor 43 for detecting the notch 41 is opposed to the peripheral portion of 42. The sensor 43 is fixed at a fixed position with respect to the star wheel 13, and the sensor 43 also rotates as the star wheel 13 rotates. That is, the rotation amount detecting means 40 revolves together with the bottle 1. As the sensor 43, a sensor that optically detects the notch 41 based on a change in the reflected light of the light projected onto the chopper plate 42 can be used. If the chopper plate 42 is made of a conductive material, a proximity sensor type that forms a high-frequency electromagnetic field and detects eddy current loss can be used, and the chopper plate 42 is made of a magnetic material. If this is done, it is also possible to use a magnetic sensor type that forms a magnetic field around and detects changes in the magnetic field. Further, as shown in FIG. 7B, a sensor 43 of a type that opposes with the chopper plate 42 in between may be used. For example, if the light is optically detected, the light blocking of the projected light by the chopper plate 42 may be detected. As the chopper plate 42, the one having the structure shown in FIG. 6 can be used as shown in FIG. Further, as shown in FIG. 8, a rotary encoder 44 may be used as the rotation amount detecting means 40. As shown in FIG. 1, the output of the rotation amount detecting means 40 is converted into a serial signal through a parallel-serial converter 2 and input to a rotation amount determining device 3 such as a counter or a sequencer. If the rotation amount determination device 3 detects that the rotation amount is one rotation or more, it is guaranteed that the bottle 1 has rotated one rotation or more. Here, the transmission signal line 4 from the parallel-serial converter 2 to the rotation amount determination device 3 is passed through, for example, a slip ring 19 provided in the bearing portion of the star wheel 13.

According to the above configuration, the rotation amount of the rotary tube 32 including the vacuum suction pad 31 that transmits the rotational force from the rotary table 22 to the bottle 1 and sucks the bottle 1 is detected by the rotation amount detecting means 40. Therefore, the rotation amount of the bottle 1 is guaranteed to be larger than the rotation amount detected by the rotation amount detecting means 40. That is, if the rotation amount detected by the rotation amount detecting means 40 is one rotation or more, it is guaranteed that the bottle 1 has also rotated one rotation or more by rotation. Further, since the bottle 1 is held in a cantilever manner, the shape of the bottle 1 is not particularly limited. Further, the rotation amount of the bottle 1 is detected by the holding means 30 holding the bottle 1. Since it is detected as the rotation amount of the rotary tube 32, it is not necessary to mark the bottle 1, and since only the rotation amount of the bottle 1 is detected, the bottle 1 revolves along with its rotation. However, the rotation amount of bottle 1 can be accurately detected.

In the above embodiment, the vacuum suction pad 31 is used as the holding means 30, but the bottle 1 may be adhered by an adhesive material, and if the work is a magnetic substance, the work is attracted by magnetic force. You may. Further, as long as the work is held in a cantilever manner, the work may be held mechanically by engaging with the work. (Embodiment 2) In this embodiment, as shown in FIG. 11, the rotation amount detecting means 40 is fixed to a code plate 45 provided on the rotary tube 32 and near both ends of the field of view VF of the TV camera 15 on the gantry 10. It is composed of a pair of sensors 43a and 43b (see FIG. 9 and FIG. 10). That is, only the code plate 45 revolves with the bottle 1. As shown in FIG. 11A, the code plate 45 is formed by forming an arc-shaped slit 46 (thick line portion) in a key portion of a light-shielding material. The slits 46 are formed on the circumference of four different diameters, and the rotation angle is indicated by a 4-bit code depending on the position where the slits 46 are formed. That is, the code plate 45 indicates an angle with a resolution of 1/16 of one round. Therefore, as shown in FIG. 11B, as the sensors 43a and 43b, if four sensor elements 47 capable of detecting the slit 46 at each position are arranged in the radial direction of the code plate 45, the sensor elements are formed. The absolute position of the rotation angle of the code plate 45 can be known by the combination of the outputs of 47.

Therefore, if the pair of sensors 43a and 43b are provided at two positions and the absolute position of the rotation angle of the code plate 45 at each position is detected, the bottle 1 moves between the sensors 43a and 43b. The rotation amount of the bottle 1 in the meantime can be known as the rotation amount of the cord plate 45. According to this configuration, since it is not necessary to provide the sensors 43a and 43b for each bottle 1, the number of the sensors 43a and 43b is reduced as compared with the first embodiment, which leads to cost reduction. is there. However, between the two sensors 43a and 43b, it cannot be distinguished that the cord plate 45 has made one-sixteenth rotation and one rotation and one-sixteenth rotation. Therefore, two sensors 43a and 43b are used. In some cases, the applicable range is limited when the bottle 1 rotates within one rotation within the visual field VF of the TV camera 15. Further, by arranging the sensors 43a and 43b at intervals such that the bottle 1 makes one rotation, the bottle 1 can be rotated a plurality of times within the range of the visual field VF of the TV camera 15. The code plate 45 has slits 46 having four different diameters, but if slits 46 having five or more different diameters are provided, the resolution for detecting the rotation amount can be increased.

In each of the above-described embodiments, the rotation amount of the bottle 1 is determined only by the rotation amount of the rotary tube 32, but based on the difference between the rotation amount of the rotary tube 32 and the rotation amount of the rotary base 22. Alternatively, the slip amount in the rotation transmission system via the bottle 1 between the driving means 20 and the holding means 30 may be detected. In this way, by detecting the difference in the amount of rotation between the driving side and the driven side, it is possible to know the performance of the element that transmits the rotation. For example, wear of the friction member 21 can be easily detected. You can do it.

[0020]

[Effect of the device]

 As described above, in the present invention, since the holding means holds one end of the work in the direction along the center line of rotation, the work is held in a cantilever manner, and there is almost no restriction on the shape of the work. There is an advantage that. Further, since the work is rotated by the drive means so that the holding means is rotated by receiving the rotational force from the work and the rotation amount of the holding means is detected by the rotation amount detecting means, the rotation amount of the work is detected by the rotation amount detecting means. It is guaranteed that the rotation amount is equal to or more than the rotation amount detected by, and if the rotation amount detected by the rotation amount detecting means is one rotation or more, it can be surely guaranteed that the work has rotated one rotation or more. Has the effect. Moreover, since the rotation amount of the transfer device is detected, it is not necessary to add a mark to the work, and the transfer device can be used even if the work revolves along with its rotation.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a first embodiment.

FIG. 2 is a plan view showing the first embodiment.

FIG. 3 is a front view showing the first embodiment.

FIG. 4 is a cross-sectional view of a main part of the first embodiment.

FIG. 5 is a schematic configuration diagram of a main part of the first embodiment.

FIG. 6 shows a rotation amount detecting means used in the first embodiment,
(A) is a top view of a chopper board, (b) is a side view.

FIG. 7 shows a rotation amount detecting means used in the first embodiment,
(A) is a top view of a chopper board, (b) is a side view.

FIG. 8 is a side view showing a rotation amount detecting means used in the first embodiment.

FIG. 9 is a plan view showing a second embodiment.

FIG. 10 is a schematic configuration diagram of a main part showing a second embodiment.

FIG. 11 shows a rotation amount detecting means used in the second embodiment,
(A) is a top view of a code board, (b) is a side view.

FIG. 12 is a schematic configuration diagram showing a conventional example.

FIG. 13 is a schematic configuration diagram showing another conventional example.

FIG. 14 is a schematic configuration diagram showing still another conventional example.

FIG. 15 is a schematic configuration diagram showing another conventional example.

[Explanation of symbols]

 1 Work (Bottle) 20 Drive Means 30 Holding Means 40 Rotation Amount Detection Means

Claims (1)

[Scope of utility model registration request] 1. A drive means for transmitting a rotational force to a work,
A rotation detecting device comprising: holding means for holding one end of a work in a direction along a rotation center line and rotating with the work; and rotation amount detecting means for detecting a rotation amount of the holding means.