JP5062414B2 - Inspection apparatus, inspection method, rolling bearing manufacturing apparatus, and rolling bearing manufacturing method - Google Patents

Description

  The present invention relates to an inspection apparatus and an inspection method for inspecting a grease application state in a rolling bearing, and to a rolling bearing manufacturing apparatus and a manufacturing method for manufacturing a rolling bearing.

A bearing is used in a hard disk of a personal computer to rotatably support a magnetic disk.
Generally, the bearing is composed of two race rings (outer ring, inner ring), rolling elements (rollers or balls), and a cage.
The bearing is coated with a lubricant such as grease to reduce the friction of the rolling elements.

Conventionally, techniques for inspecting the application state of grease on a bearing have been proposed in the following patent documents.
JP 2000-343024 A JP 2007-240526 A

Patent Document 1 proposes a technique for imaging a bearing in a state of being irradiated with ultraviolet light and inspecting the application state of a lubricant on a rolling bearing based on the captured image.
Specifically, imaging is performed by irradiating a near-ultraviolet ray to a bearing including a raceway (outer ring, inner ring), a metal rolling element (ball), and a resin cage.
Lubricant is reflected in white because it emits light upon receiving ultraviolet light, and rolling elements are projected in black. And based on the area of the white area | region in a captured image, the state of the lubricant apply | coated to the rolling element is inspected.

  In Patent Document 2, visible light illumination is applied to a bearing, a transmission image thereof is captured by a monochrome camera, and a lubricant application state in a cage is determined based on detection results of a visible light transmission region and a non-transmission region. A technique for determining the above has been proposed. In addition to the above inspection, Patent Document 2 discloses a technique for irradiating a bearing with ultraviolet light illumination, capturing the irradiated image with a monochrome camera, and determining whether or not there is grease adhesion on a metal rolling element. Proposed.

However, in the inspection method described in Patent Document 1, when irradiated with ultraviolet light, both the resin cage and the lubricant are projected white by the excitation light of the ultraviolet light. It was difficult to distinguish.
Further, in the inspection method described in Patent Document 2, it is easy to distinguish between the cage and the grease by irradiating visible light, but the application state of the grease at the two locations of the cage and the rolling element is determined. Therefore, it is necessary to take an image in a state where each of visible light and ultraviolet light is irradiated alone. That is, it is necessary to perform the imaging process twice in the inspection of the grease application state.

  Therefore, an object of the present invention is to reduce the number of times of imaging processing when inspecting the application state of the lubricant to the cage and the rolling elements.

(1) In order to achieve the above object, in the first aspect of the present invention, the outer ring, the inner ring, a plurality of rolling elements disposed between the outer ring and the inner ring, and the rolling element are separated. An inspection device for inspecting the application state of a lubricant having a fluorescent component in a rolling bearing provided with a light-transmitting cage, a first light source for irradiating visible light, and a first light source for irradiating ultraviolet light. An imaging means for capturing a color image of the rolling bearing to be inspected from the irradiation side of the ultraviolet light in a state where two light sources, and the visible light and the ultraviolet light are irradiated to the rolling bearing to be inspected from opposite directions, respectively. And based on at least one of color information and luminance information of the captured image, first inspection area specifying means for specifying a first inspection area for the rolling element from a captured image captured by the imaging means, In the inspection area Takes a first inspection means for inspecting the state of adhesion of the lubricant, from the captured image, and a second inspection area specifying means for specifying a second inspection region with respect to the retainer, in the captured image, the excitation light by the ultraviolet light The lubricant application region is detected based on the color difference between the color mixture region of the visible light and the light emission region of the lubricant, and the lubricant application state in the second inspection region based on the detection result And a second inspection means for inspecting the inspection apparatus.
( 2 ) In the invention described in claim 2 , the first inspection area is provided with coordinate recognition means for recognizing the coordinates of the vertex of the rolling element in the captured image, and based on the recognized vertex coordinate of the rolling element. and it provides a test apparatus according to claim 1 Symbol placement and identifies at least one of the second inspection area.
( 3 ) In the invention described in claim 3 , in the inspection apparatus comprising a first light source for irradiating visible light, a second light source for irradiating ultraviolet light, and a color image imaging means, an outer ring and an inner ring And a plurality of rolling elements disposed between the outer ring and the inner ring, and a cage having a fluorescent component in a rolling bearing provided with a cage that separates the rolling elements and has light permeability. An inspection method for inspecting a state, wherein the visible light and the ultraviolet light are irradiated on the rolling bearing to be inspected from opposite directions, respectively, and the color of the rolling bearing to be inspected from the irradiation side of the ultraviolet light A first step of capturing an image, a second step of identifying a first inspection region for the rolling element from the captured image captured in the first step, and at least one of color information and luminance information of the captured image. There are, the third step of inspecting the state of adhesion of the lubricant in the first inspection area, from the captured image, and a fourth step of identifying a second inspection region with respect to the retainer, in the captured image, the ultraviolet light The lubricant application region is detected based on the color difference between the color mixing region of the excitation light and the visible light generated by the light source and the light emitting region of the lubricant, and the lubricant in the second inspection region is detected based on the detection result. And a fifth step of inspecting the coating state of the coating.
( 4 ) In the invention according to claim 4 , an assembling apparatus for assembling a rolling bearing comprising at least an outer ring, an inner ring, a plurality of rolling elements, and a light-transmitting cage, and a predetermined of the assembled rolling bearing A rolling bearing manufacturing apparatus comprising: a lubricant applying device that applies a lubricant at a position; and an inspection device that detects a lubricant application state in the rolling bearing coated with the lubricant, wherein the inspection is performed. The apparatus is an inspection apparatus according to claim 1 or claim 2 , and provides a rolling bearing manufacturing apparatus.
(5) In the invention described in claim 5, wherein the lubricant applying device, based on the inspection result of the inspection apparatus, according to claim 4, wherein the rolling bearing, characterized in that to adjust the application position of the lubricant Providing manufacturing equipment.
( 6 ) In the invention described in claim 6 , an eleventh step of assembling a rolling bearing including at least an outer ring, an inner ring, a plurality of rolling elements, and a light-transmitting cage, and the assembled rolling bearing A twelfth step of applying a lubricant at a predetermined position, a thirteenth step of detecting an application state of the lubricant in a rolling bearing coated with the lubricant by an inspection method according to claim 3 , and the thirteenth step. And a fourteenth step of adjusting the lubricant application position based on the detection result of the lubricant application state in the step, wherein the twelfth step is to apply the lubricant at the application position adjusted in the fourteenth step. The present invention provides a method for manufacturing a rolling bearing characterized by applying the same.

  According to the present invention, the lubricant in the rolling elements and the cage is captured in one captured image by capturing a bearing image projected by transmitted light by visible light and excitation light by ultraviolet light as a color image. Each existing part can be characteristically copied. Thereby, since the state inspection of the lubricant in the cage and the rolling element can be performed by one imaging process, the inspection time can be shortened.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
(1) Outline of Embodiment In the bearing manufacturing line, after assembling the inner ring, outer ring, ball and cage constituting the bearing in the assembly process, lubricant is applied to a predetermined lubricant application position provided on the cage. To do. Next, the application state of the lubricant in the bearing to which the lubricant has been applied is inspected.
In the inspection process of the lubricant application state, the lubricant application state in the cage and the lubricant adhesion state in the ball are inspected.
Here, the bearing placed on the pallet is irradiated with ultraviolet light from above, and red visible light is irradiated from below (back side), and a color image of the bearing is taken from above the pallet. In one color captured image captured here, a bearing image projected by transmitted light by visible light and excitation light by ultraviolet light is projected. Then, the application state of the lubricant is inspected based on the captured color image.

The lubricant applied to the bearing is mixed with an additive having a fluorescent component in advance. Therefore, the lubricant on the ball emits fluorescence upon receiving ultraviolet light. Therefore, the adhesion state of the lubricant on the ball (for example, the presence or absence of the lubricant on the ball) is determined based on the color difference between the lubricant adhesion region and the non-adhesion region on the ball in the captured image.
Since the cage is made of a permeable resin, the area of the cage that is not coated with lubricant is reflected in purple due to a mixture of excitation light (blue light) by ultraviolet light and red visible light. It is. In addition, the region where the lubricant is applied in the cage does not transmit red visible light, but is reflected in blue because it emits fluorescence when receiving ultraviolet light. Therefore, the state of application of the lubricant in the cage (for example, a lot of lubricant, a small amount, an appropriate amount, or nothing at all) is based on the difference in color between the lubricant adhering area and the non-adhering area on the cage in the captured image. Judgment.
In this embodiment, based on the result of the inspection process of the application state of the lubricant, not only the good and defective bearings are determined, but also the position of the nozzle of the lubricant application device is adjusted.

(2) Details of Embodiment FIG. 1 is a diagram showing a schematic configuration of a bearing production line.
As shown in FIG. 1, the bearing manufacturing line includes an inner ring supply device 41, an outer ring supply device 42, a ball supply device 43, a ball distribution device 44, a cage assembly device 45, a lubricant application device 46, and a lubricant inspection device. 1. A defective lubricant discharge device 47, a torque inspection device 48, an acoustic inspection device 49, a defective discharge device 50, a non-defective product collection device 51, a display device 52, and a control device 60 are provided.

The bearing 2 manufactured in the bearing manufacturing line is mounted on the transport pallet 17. The conveyance pallet 17 is conveyed by the pallet conveyance conveyor 19 to the arrangement place of each apparatus.
One bearing 2 is mounted on one transport pallet 17. Each transport pallet 17 is assigned a pallet number 70 for identifying the bearing 2. The pallet number 70 is printed on a sticker in an optically readable state, and this sticker is affixed to a predetermined part of each transport pallet 17.
Also, the pallet number 70 is assigned to each of the lubricant application device 46, the lubricant inspection device 1, the lubricant failure discharge device 47, the torque inspection device 48, the acoustic inspection device 49, the failure discharge device 50, and the non-defective product collection device 51. An optical reading device is provided.

Here, the bearing 2 manufactured with the bearing manufacturing line which concerns on this embodiment is demonstrated.
FIG. 2A is a diagram showing a schematic configuration of the bearing 2, and FIG. 2B is a diagram showing a cross section taken along the line AA 'shown in FIG. 2A.
As shown in the figure, the bearing 2 is a rolling bearing including an outer ring 21, an inner ring 22, a ball 23, and a cage 24.
The outer ring 21 is a metal annular member that is disposed outside the inner ring 22 and has a larger diameter than the inner ring 22, and a groove that forms a track of the ball 23 along the circumferential direction is formed on the inner circumferential surface thereof. Is formed.
The inner ring 22 is a metal annular member that is disposed inside the outer ring 21 and has a smaller diameter than the outer ring 21, and a groove that forms a track of the ball 23 is formed on the outer surface of the inner ring 22 along the circumferential direction. Has been.

The ball 23 is a metal spherical rolling element disposed between the outer ring 21 and the inner ring 22, and a part of the ball 23 is fitted in a groove forming a track formed in the outer ring 21 and the inner ring 22. .
A plurality of balls 23 are disposed between the outer ring 21 and the inner ring 22.
The cage 24 is an annular member for arranging a plurality of balls 23 disposed between the outer ring 21 and the inner ring 22 at a constant interval so as not to contact each other, and transmits visible light ( It is made of a resin that has optical transparency. On the inner surface of the cage 24, a groove that forms a track of the ball 23 is formed along the circumferential direction.

FIG. 2C is a perspective view showing a schematic configuration of the cage 24.
As shown in the figure, the cage 24 is provided with a pocket 241 into which the ball 23 is fitted, and a lubricant reservoir 242 to which a lubricant is applied.
The pockets 241 are grooves for holding the balls 23, and are provided at equal intervals along the circumferential direction of the cage 24.
The lubricant reservoir 242 is a portion to apply a lubricant such as grease (grease) or lubricating oil for reducing friction of the balls 23, and is provided between adjacent pockets 241.

In the present embodiment, the lubricant (grease) applied to the bearing 2 is preliminarily added with, for example, an amine-based antioxidant that emits fluorescence when receiving ultraviolet light. That is, the lubricant applied to the bearing 2 contains a fluorescent component.
The antioxidant added to the lubricant is in a stable form by using two types of antioxidants, a primary antioxidant (radical chain inhibitor) and a secondary antioxidant (peroxide decomposer). .
When radicals (free radicals) are generated by heat or light, peroxy radicals are generated by oxygen. What makes this peroxy radical a stable radical is a primary antioxidant, which corresponds to a phenol-based or amine-based oxidant. The secondary antioxidant that decomposes the peroxide generated thereafter is a sulfur-based or phosphorus-based oxidizing agent.
In the present embodiment, a lubricant to which phenol-based and amine-based antioxidants are added is applied to the bearing 2.
Phenol-based oxidizing agents have little colorability and are used at relatively low temperatures. Amine-based oxidizing agents have a high antioxidant effect and are used at relatively high temperatures.

Returning to the description of FIG. 1, the apparatus provided in the bearing production line will be described.
The inner ring supply device 41, the outer ring supply device 42, and the ball supply device 43 are devices that supply the inner ring 22 (see FIG. 2), the outer ring 21, and the balls 23, which are constituent members of the bearing 2, onto the transport pallet 17.
In the present embodiment, an eccentric assembly method is used when the bearing 2 is assembled. In this eccentric assembly method, the outer ring 21 is eccentrically placed on the outer side of the inner ring 22, the balls 23 are sequentially placed from the outside into the raceway groove, and then the inner ring 22 is moved from the eccentric position to the concentric position. It is a method of incorporation.
The ball distribution device 44 is a device that arranges (arranges) the balls 23 supplied between the inner ring 22 and the outer ring 21 at equal intervals. In the ball distribution device 44, for example, a positioning jig in which comb teeth are set at a position corresponding to the interval between the balls 23 is used.
The cage assembly device 45 is a device that incorporates the cage 24 between the inner ring 22 and the outer ring 21.

The lubricant application device 46 is a device that applies a lubricant to the lubricant reservoir 242 of the cage 24. The lubricant application device 46 is provided with a plurality of nozzles for applying the lubricant, and is configured so that the lubricant can be applied to the lubricant reservoir 242 simultaneously.
The lubricant application device 46 controls the amount of lubricant to be applied by adjusting the nozzle opening time, that is, the application time and the injection pressure (pressing force).
The plurality of nozzles for applying the lubricant are arrayed and fixed along the circumferential direction corresponding to the site where the lubricant reservoir 242 is formed. Therefore, in the present embodiment, position correction control can be performed with respect to a shift in the rotation direction of the application position and a shift in the center position.
Note that the position of the nozzle when applying the lubricant is set based on the absolute position information of the ball 23 specified by the ball distribution device 44 or the cage assembly device 45.

The lubricant inspection apparatus 1 is an apparatus that inspects the application state of the lubricant applied to the lubricant reservoir 242, that is, determines whether or not an appropriate amount of lubricant is applied to an appropriate position. The details of the lubricant inspection device 1 will be described later.
The lubricant failure discharge device 47 is a device that discharges the bearing 2 that has been determined to be defective in the lubricant application state by the inspection of the lubricant inspection device 1 together with the transport pallet 17 to a predetermined failure discharge area.
The processing of the bearing 2 discharged by the lubricant failure discharging device 47 is determined based on the inspection result of the lubricant application state. For example, when the lubricant has not been applied, the lubricant is applied again to the lubricant application device 46, and when the lubricant is defective, offline correction, that is, manual correction by the operator (manual correction) is performed. The

The torque inspection device 48 is a device that measures the rotational torque of the bearing 2. The torque inspection device 48 determines that the product is non-defective when the measurement result is within a predetermined torque value range, and determines that the torque is defective when the measurement result is out of range.
The acoustic inspection device 49 is an inspection device that determines quietness when the bearing 2 rotates. The acoustic inspection device 49 determines the state of polishing of the raceway groove based on the level of noise caused by high-speed rotation, and determines that the noise level exceeds a predetermined threshold value as defective.
The defect discharge device 50 is a device that discharges the bearing 2 that is determined to be defective by the inspection of the torque inspection device 48 or the acoustic inspection device 49 together with the transport pallet 17 to a predetermined defect discharge area.

The non-defective product collecting device 51 is a device that stores the bearing 2 that has been determined to be non-defective that has passed the inspections of the torque testing device 48 and the acoustic testing device 49 together with the transport pallet 17 in a predetermined good product collecting area.
The display device 52 is a device that performs display related to the operation processing of the lubricant application device 46 disposed in the vicinity of the lubricant application device 46, and displays information of three colors of red, yellow, and green, and information. A display is provided. In the display device 52, when a lubricant application failure occurs, a yellow or red indicator lamp is turned on according to the generation condition, and a green indicator lamp is turned on at normal times.
The control device 60 is a device for managing the operations of various devices provided in the bearing production line and the pallet transport conveyor 19, and is configured by a computer having functions of input, storage, calculation, control, and output. The storage unit of the control device 60 stores a program showing a series of processing procedures such as assembly, lubricant application, and inspection, and the CPU of the control device 60 executes this program.

Next, the manufacturing process of the bearing 2 in the bearing manufacturing line configured as described above will be described.
FIG. 3 is a flowchart showing a procedure for manufacturing the bearing 2 in the bearing manufacturing line.
First, in the bearing production line, the inner ring supply device 41, the outer ring supply device 42, the ball supply device 43, the ball distribution device 44, and the cage assembly device 45 perform assembly processing of the members constituting the bearing 2 (step). 11).
Specifically, the inner ring supply device 41 mounts the inner ring 22 on the transfer pallet 17 to which the pallet number 70 is attached, which is transferred by the pallet transfer conveyor 19. Subsequently, the outer ring supply device 42 places the outer ring 21 eccentrically on the outer side of the inner ring 22. Then, the ball supply device 43 supplies the ball 23 between the outer ring 21 and the inner ring 22.
After supplying the ball 23, the ball supply device 43 moves the inner ring 22 from the eccentric position to the concentric position. Then, after the balls equalizing device 44 arranges the balls 23 supplied between the inner ring 22 and the outer ring 21 at equal intervals, the cage 24 is inserted between the inner ring 22 and the outer ring 21 by the cage assembly device 45. Is incorporated.

Next, the assembled bearing 2 is transported to the lubricant application device 46 by the pallet transport conveyor 19. Then, the lubricant application device 46 performs a process of applying the lubricant to the lubricant reservoir 242 in the cage 24 of the bearing 2 (step 12).
Note that the lubricant application device 46 reads the pallet number 70 by the reader before (or after) applying the lubricant. Then, the read pallet number 70 and the lubricant application condition information in the bearing 2 mounted on the transport pallet 17 to which the pallet number 70 is attached are associated with each other and transmitted to the control device 60. Examples of the lubricant application condition information include the nozzle opening time of the lubricant, nozzle position information, and a pressing value (injection pressure value).
The control device 60 receives the data transmitted from the lubricant application device 46 and stores it in a predetermined storage area.

The bearing 2 subjected to the lubricant application process is conveyed to the lubricant inspection apparatus 1 by the pallet conveyor 19. And the process which test | inspects the application state of the lubricant in the bearing 2 is performed by the lubricant inspection apparatus 1 (step 13). Details of the inspection process of the application state of the lubricant performed here will be described later.
In the lubricant inspection device 1, the pallet number 70 is read by the reading device before (or after) the inspection process. Then, the read pallet number 70 and the inspection result of the bearing 2 mounted on the transport pallet 17 to which the pallet number 70 is attached are associated with each other and transmitted to the control device 60.

The control device 60 receives the inspection result transmitted from the lubricant inspection device 1 and stores it in a predetermined storage area.
Subsequently, based on the inspection result of the lubricant inspection device 1, the control device 60 determines whether or not the bearing 2 mounted on the transport pallet 17 with the pallet number 70 has passed the inspection of the lubricant application state. Then, it is determined whether or not OK is determined (step 14).
When the inspection of the application state of the lubricant has passed (step 14; Y), the transport pallet 17 to which the pallet number 70 is attached is transported to the torque inspection device 48. In this case, the transport pallet 17 is not a target for discharge by the defective lubricant discharge device 47.
Then, the inspection by the torque inspection device 48 and the acoustic inspection device 49 is continued (step 15).
In the torque inspection device 48 and the acoustic inspection device 49, the pallet number 70 is read by the reading device before (or after) each inspection process. Then, the read pallet number 70 and the inspection result of the bearing 2 mounted on the transport pallet 17 to which the pallet number 70 is attached are associated with each other and transmitted to the control device 60.
The control device 60 receives data transmitted from the torque inspection device 48 and the acoustic inspection device 49 and stores it in a predetermined storage area.

Subsequently, based on the inspection results of the torque inspection device 48 and the acoustic inspection device 49, the control device 60 determines whether or not the bearing 2 mounted on the transport pallet 17 of the pallet number 70 has passed both inspections, It is determined whether or not an OK determination has been made (step 16).
When both the torque and sound inspections are passed (step 16; Y), the transport pallet 17 with the pallet number 70 attached is transported to the non-defective product collecting device 51 and put into a predetermined storage area by the non-defective product collecting device 51. It is collected (step 17) and the process is terminated. In this case, the transport pallet 17 is not a target for discharge by the defective discharge device 50.
If both the torque and sound inspections are not passed (step 16; N), the transport pallet 17 to which the pallet number 70 is attached is transported to the defective discharge device 50, and the defective discharge device 50 performs a predetermined defect. Collected in the discharge area (step 18), the process is terminated.

On the other hand, when the inspection of the application state of the lubricant is not passed in the process of step 14 (step 14; N), the control device 60 determines the lubricant based on the inspection result transmitted from the lubricant inspection device 1. Feedback control of the coating device 46 is performed (step 19). The details of the feedback control of the lubricant application device 46 will be described later.
The bearing 2 that has not passed the inspection of the lubricant application state, that is, the transport pallet 17 on which the bearing 2 determined to be defective (NG) is mounted is transported to the lubricant failure discharging device 47. Then, it is discharged to a predetermined defective discharge area by the defective lubricant discharge device 47 (step 20), and the process is completed.

When manufacturing a type of bearing that incorporates a shield plate in the bearing production line, a shield plate assembly device is further provided, and after the inspection in the lubricant inspection device 1 is completed, the bearing 2 that has passed this inspection is shielded. Incorporate a board. That is, in the bearing production line, the torque inspection and the acoustic inspection are performed after the shield plate is incorporated.
The shield plate is an annular cover member arranged so as to cover the raceway region in order to prevent leakage of lubricant to the outside of the bearing 2 and inflow of dust to the inside of the bearing.

Next, the lubricant inspection apparatus 1 will be described in detail.
FIG. 4 is a diagram showing a schematic configuration of the lubricant inspection device 1.
As shown in FIG. 4, the lubricant inspection device 1 includes a camera 11, a lens 12, a sharp cut filter 13, a light shielding hood 14, a back illumination 15, and an ultraviolet light illumination 16.
A bearing 2 as a specimen (sample) to be inspected is placed on the transport pallet 17 transported by the pallet transport conveyor 19.
The conveyance pallet 17 has a structure in which at least a region where the bearing 2 is disposed is formed of a material that transmits light or transmits light.
The bearing 2 is a small rolling bearing having a diameter of about 10 to 5 mm used for a hard disk or the like, for example.

In addition, the lubricant inspection apparatus 1 is provided with an image processing apparatus 30 that processes a captured image of the bearing 2 captured by the camera 11.
The image processing apparatus 30 is configured by, for example, a PC (personal computer) having input, storage, calculation, control, and output functions, and an image analysis program for inspecting the lubricant application state on the bearing 2, A determination program for determining pass / fail is stored.

The camera 11 is an optical machine that takes a picture. In the lubricant inspection apparatus 1 according to the present embodiment, the camera 11 is a color digital camera that digitizes and records an image. In the present embodiment, the camera 11 includes a CCD camera. Yes. Note that the color image captured by the camera 11 is transferred to the image processing device 30. The camera 11 functions as an imaging unit.
The lens 12 is attached to the camera 11 and has a function of adjusting the focus (focus) of the camera 11. In the present embodiment, the lens 12 is adjusted so that a blue image is in focus. The lens 12 is disposed at a position 115 mm from the workpiece.
In the present embodiment, a close-up ring (5 mm) is attached between the camera 11 and the lens 12 in order to enable close-up shooting with the camera 11.
The sharp cut filter 13 is a special transmission filter that removes only light of a specific wavelength, and functions as a noise cut filter.

The light shielding hood 14 is a cover for shielding external light reflection such as reflection of extraneous light, and includes, for example, a light shielding plate or a light shielding curtain (dark curtain). The light shielding hood 14 is disposed so as to sufficiently cover the camera 11, the lens 12, the sharp cut filter 13, the ultraviolet light illumination 16, and the back illumination 15.
The back illumination 15 is a flat illumination composed of a light emitting diode that emits red light (visible light) having a wavelength of about 650 nm, and functions as a visible light source that emits visible light. The back illumination 15 has a structure that allows light from a chip-shaped LED (light emitting diode) spread on a flat substrate to pass through the diffusion plate, and passes through the bearing 2 to be inspected as a silhouette from behind. In this embodiment, red light is used as the back illumination 15, but the color of visible light that irradiates the bearing 2 is not limited to this, and can be distinguished from the color of ultraviolet excitation light. Any color type (for example, green) may be used.

The ultraviolet light illumination 16 is a light emitting diode that emits ultraviolet (UV) light, and functions as an ultraviolet light source that emits ultraviolet light.
The ultraviolet light illumination 16 is composed of a plurality of LEDs arranged in an annular shape (ring shape), and each LED is focused on the bearing 2.
Since the ultraviolet light is weak light, in the present embodiment, the ultraviolet light illumination 16 is arranged at a position closer to the bearing 2 (workpiece) that is the irradiation target. Specifically, the ultraviolet light illumination 16 is disposed at a position 80 mm from the workpiece.
Further, in the present embodiment, considering that the excitation light by ultraviolet light is weak light, the output ratio (brightness ratio) of the back illumination 15 and the ultraviolet light illumination 16 is set to, for example, about 1:10. .

In the present embodiment, it is possible to extend the life of the light source by configuring the light source of the back illumination 15 or the ultraviolet light illumination 16 with an LED (light emitting diode). In addition, by using an LED as a light source, it is possible to irradiate a target light beam without emitting infrared rays, so that a sharp captured image can be obtained.
The conveyance pallet 17 is a mounting base for placing the bearing 2 as a specimen (sample) to be inspected. The side end of the transport pallet 17 is supported by two belts constituting the pallet transport conveyor 19. And the conveyance pallet 17 has the structure where the area | region where the bearing 2 is arrange | positioned is formed with the raw material which permeate | transmits light, or permeate | transmits light.
In the present embodiment, since the bearing 2 is small, the field of view in the illumination inspection in the measurement system described above is about 10 mm square.

Next, a method for inspecting the application state of the lubricant applied to the bearing 2 by the lubricant inspection device 1 according to the present embodiment will be described.
The lubricant inspection apparatus 1 inspects the lubricant application state in the cage 24 and the lubricant application state (attachment state) in the balls 23 based on the captured color image of the bearing 2.
FIG. 5 is a flowchart showing a procedure of processing for inspecting the application state of the lubricant in the lubricant inspection device 1.

First, the lubricant inspection apparatus 1 moves and fixes the conveyance pallet 17 on which the bearing 2 as a specimen (sample) to be inspected is moved to an imageable area by the camera 11 (step 31).
The lubricant inspection device 1 turns on the back illumination 15 and the ultraviolet illumination 16, and irradiates the bearing 2 with light rays from both light sources (step 32).
Then, a transmitted image that has passed through the bearing 2 in the red light (visible light) irradiated from the back illumination 15 and an image of excitation light generated in a portion that is exposed to the ultraviolet light irradiated from the ultraviolet light illumination 16 are displayed. It is.
The lubricant inspection device 1 captures (captures) an image of the bearing 2 in a state in which the back illumination 15 and the ultraviolet light illumination 16 are irradiated (step 33).
Here, the image is taken (photographed) at a shutter speed (speed) of 1/30 seconds. In the present embodiment, imaging is performed by focusing on the excitation light region (blue light emission region) of ultraviolet light.
A bearing image projected by the transmitted light by the back illumination 15 (visible light) and the excitation light by the ultraviolet light illumination 16 (ultraviolet light) is projected on one color image captured image captured here.
After the imaging process is completed, the lubricant inspection device 1 turns off the back illumination 15 and the ultraviolet light illumination 16 (step 34).

An image (captured image) of the bearing 2 captured by the camera 11 is transferred to the image processing device 30. Then, the image processing device 30 determines the application state of the lubricant based on the captured image of the bearing 2.
Here, a captured image of the bearing 2 captured by the camera 11 will be described.
FIG. 6 is a diagram illustrating an example of a captured image.
Since the ball 23 is made of a metal member having no transparency, the ball 23 does not transmit visible light from the back illumination 15. Further, since the surface of the ball 23 is a sphere, the ultraviolet light and the excitation light of the ultraviolet light are also irregularly reflected. Therefore, most of the area of the ball 23 in the captured image is displayed in black.
However, as shown in FIG. 6, the portion where the light irradiated from the ultraviolet light illumination 16 is regularly reflected, that is, the central portion of the surface of the ball 23 is projected as whitish because of extremely high brightness (luminance).

Since the outer ring 21 and the inner ring 22 are also made of a metal member that does not have transparency, the visible light from the backlight 15 is not transmitted. Therefore, the areas of the outer ring 21 and the inner ring 22 are projected with blue light in the ultraviolet light.
The region of the lubricant reservoir 242 in the cage 24 is displayed in purple due to the color mixture of the excitation light (blue light) by the ultraviolet light illumination 16 (ultraviolet light) and the back illumination 15 (red light). However, the purple color is displayed only in the region where the lubricant is not applied in the lubricant reservoir 242.
The region where the lubricant is applied (hereinafter referred to as the lubricant region 243) does not transmit visible light from the back illumination 15, and the components contained in the lubricant receive ultraviolet light and emit fluorescence. Projected in blue.

The portion of the cage 24 forming the pocket 241 (see FIG. 2C), that is, the vicinity of the ball 23 in the cage 24 is projected in blue. This is because the back illumination 15 has a large thickness in the light transmission direction, and thus excitation light (blue light) from the ultraviolet illumination 16 (ultraviolet light) is more strongly projected than the back illumination 15 (red light).
A region (background) where the components of the bearing 2 (outer ring 21, inner ring 22, ball 23, cage 24) do not exist is displayed in red by the back illumination 15.

Returning to the description of the flowchart of FIG. 5, the image processing apparatus 30 detects the position of the ball 23 in the captured image in order to recognize the position of the sample (bearing 2) in the captured image as shown in FIG. 35).
Here, a method for recognizing the position of the bearing 2 in the captured image will be described.
First, the image processing apparatus 30 performs color extraction so as to extract the blue regions of the outer ring 21 and the inner ring 22 in FIG. Here, the color to be extracted is adjusted so as not to recognize the parts of the ball 23 and the cage 24, and the position of the workpiece (bearing 2) is recognized. Then, the absolute position of the bearing 2 on the captured image is recognized.

Subsequently, the image processing apparatus 30 performs color conversion of the color image into a gray image in order to increase processing efficiency. Then, based on the information on the absolute position (XY coordinates) of the bearing 2 recognized previously, a region between the outer ring 21 and the inner ring 22 where the ball 23 exists is extracted.
Further, the image processing apparatus 30 adjusts the brightness (luminance) so that the apex of the ball 23 becomes brighter in order to easily detect the position of the ball 23 in the extracted area. In this embodiment, since the color image is color-converted into a gray image, the vertex of the ball 23 can be highlighted by adjusting (specifying) the brightness. However, when the position of the ball 23 is detected directly from the color image without performing the gray image conversion process, not only the lightness but also the saturation and hue of the color information are adjusted so that the vertex of the ball 23 becomes bright ( specify.

Further, it is possible to recognize the position of the ball 23 when the brightness is adjusted so that the apex of the ball 23 can be detected. However, in this embodiment, in order to suppress (reduce) an error in the detection position of the ball 23, that is, to improve the detection accuracy of the position of the ball 23, a correction process for the vertex image of the ball 23 is further performed.
In the present embodiment, the position (coordinate) detection processing of the ball 23 is performed based on particle analysis (blob) processing.
Specifically, after the color information (lightness and the like) is averaged at the apex portion of the ball 23, the binarization process is performed based on a predetermined threshold value. Thereafter, the image is expanded and contracted in order to remove small noise in the binary image.
Expansion means processing to make a pixel thick by one layer, and contraction means processing to make a pixel thin by one layer. Small holes and grooves are removed by expansion, and isolated points and protrusions are removed by contraction.
In the present embodiment, the expansion process is performed three times and the contraction process is performed once so that the top of the ball 23 is rounded. The number of expansions and contractions can be arbitrarily changed according to the captured image and the measurement environment.
In such a state that image processing has been performed, the XY coordinates of the vertices (centers of white circles) of all the balls 23 are obtained (detected). The XY coordinates obtained here are stored (specified) as position information of the ball 23.

Note that the method of detecting (recognizing) the position of the ball 23 in the captured image is not limited to that described above.
For example, the position of the ball 23 may be detected based on the amount of deviation between a preset reference image (default image) of the bearing 2 and the captured image.
Specifically, the color is extracted so as to extract the blue regions of the outer ring 21 and the inner ring 22 in FIG. 6, and the position of the workpiece (bearing 2) is detected. Based on this detection result, the amount of deviation from the reference image in the XY direction is detected. Further, the coordinates of the apex portion of the ball 23 are detected by adjusting the brightness and the like so that the apex portion of the ball 23 can be detected. Corner).
As described above, the position of the ball 23, that is, the installation state of the bearing 2 may be recognized based on the amount of deviation from the reference image in the XY direction and the θ direction in the captured image. That is, the position of the ball 23 in the captured image may be detected using a normalized correlation method using the ball 23 as a model.
Then, the position of the captured image may be corrected based on the amount of deviation from the reference image, and the first inspection region and the second inspection region described later may be specified.

Returning to the description of the flowchart of FIG. 5, after detecting the position of the ball 23 in the captured image, the image processing apparatus 30 first performs an inspection process on the lubricant region 243 in the ball 23.
Next, the image processing device 30 specifies the first inspection region from the captured image that has been subjected to the correction processing (step 36). The first inspection area is specified based on the position information of the ball 23.
In the present embodiment, an area of the ball 23 is set as the first inspection area. Note that the central portion of the surface of the ball 23 that appears white due to regular reflection of the irradiated light may be removed from the first inspection region in advance.

Here, an arbitrary area can be set as the first inspection area. For example, a range from the center of the ball 23 to the radius R of the ball 23 may be set as the first inspection region.
However, when the first inspection area is set based on the radius R of the ball 23, the image area of the outer ring 21, the inner ring 22, and the cage 24 is included in the area of the radius R.
Therefore, the area of the region that is not the image region of the ball 23 included in the region of the radius R is calculated based on the reference image in advance, and finally when determining (calculating) the lubricant application state (application amount), An area that is not an image area of the ball 23 is excluded from the determination target area.
Thereby, the detailed inspection process of the lubricant application state on the ball 23 can be performed.

Subsequently, the image processing apparatus 30 performs extraction processing of the lubricant region 243 in the specified first inspection region (step 37).
Specifically, the image processing apparatus 30 converts the brightness / saturation of each pixel of the captured image so that the blue region is converted to white and the black region is converted to black with respect to the first inspection region or the region including the first inspection region. The degree and hue are adjusted and binarized.
In the present embodiment, the purple region and the red region are also converted to white, and only the region where the lubricant of the ball 23 is not attached is converted to black.
Further, in this embodiment, when performing the extraction process of the lubricant region 243 in the first inspection region, the image is expanded and contracted in order to remove a small noise of the binary image. Specifically, each of the expansion and contraction processes is performed once. The number of expansions and contractions can be arbitrarily changed according to the captured image and the measurement environment.

Here, a specific example of the extraction process of the lubricant region 243 in the first inspection region performed in the image processing apparatus 30 will be described.
Here, the case where the lubricant region 243 exists on the ball 23 as shown in FIG.
FIG. 7B is a diagram illustrating an example of a captured image.
As shown in FIG. 7B, the lubricant region 243 is projected in blue because it emits fluorescence in response to ultraviolet light.
Then, by performing color adjustment and binarization processing on the captured image so that only the black region of the image remains black and at least the lubricant region 243 is converted to white, FIG. The captured image shown is converted into a binarized image shown in FIG.

Next, the image processing apparatus 30 extracts a white region, that is, a lubricant region 243 from the first inspection region on the ball 23 specified in the binarized image. For example, a white region in the first inspection region is extracted from the binarized image as shown in FIG. 7C, and the area is calculated.
Then, the image processing apparatus 30 compares the area value of the extracted white region (lubricant region 243) with the area value of the specified first inspection region. The identified first inspection region is indicated by a broken line in FIG.
The white area extraction process can be performed based on the luminance (brightness) information of the image. Specifically, using a preset threshold value for extracting a white region, a region having a luminance higher than the threshold value is extracted as a white region.

As shown in FIG. 7C, when the center portion of the surface of the ball 23 that appears white due to regular reflection of the irradiated light is included in the inspection area, it is projected white from the area value of the extracted white area. The area of the center portion of the surface of the ball 23 is subtracted, and the area value of the subtracted white area is compared with the area value of the specified inspection area. That is, a white region that is highly likely to indicate the lubricant application region is extracted and the comparison process is performed.
Note that the method of extracting the region indicating the lubricant application region is not limited to the method of extracting the white region from the binarized image based on the luminance information. For example, a blue region indicating a lubricant application region may be extracted from a directly captured image based on color information without performing binarization processing.

Returning to the description of the flowchart of FIG. 5, the image processing apparatus 30 calculates the ratio of the white region (lubricant region 243) to the specified first inspection region (broken line region), and sets the calculated result and the preset value. The appropriate reference range is compared, and lubricant adhesion is determined based on the comparison result (step 38). The lubricant adhesion determination process is performed on the first inspection area in all the balls 23.
When the calculated result is within the proper reference range, the image processing apparatus 30 determines that the existence range of the lubricant region 243 in the ball 23 is good, while the calculated result is out of the proper reference range. If it is, it is determined that the existence range of the lubricant region 243 in the ball 23 is defective.
When it is determined only whether or not the lubricant is attached (contacted) to the ball 23, a white area (lubricant area 243) is detected from the specified first inspection area (broken line area). Only determine whether or not.

After the inspection process of the lubricant region 243 in the ball 23 is completed, the image processing apparatus 30 subsequently performs the inspection process of the lubricant region 243 in the cage 24.
The image processing device 30 identifies the second inspection region from the captured image that has been subjected to the correction processing (step 39).
In the present embodiment, the region of the lubricant reservoir 242 of the cage 24 is set as the second inspection region. This second inspection area can be specified based on the position information of the ball 23.

Here, an arbitrary area can be set as the second inspection area. For example, the range of the radius r from the center of the lubricant reservoir 242 in the cage 24 may be set as the inspection region.
However, when this radius r region extends outside the cage 24, the area of the region (outer ring 21, inner ring 22, ball 23, gap) other than the cage 24 included in this region is previously determined based on the reference image. Calculate it. When the lubricant application state (application amount) is finally determined (calculated), the region that is not the cage 24 is excluded from the determination target region. Thereby, the inspection process of the application state of the lubricant in the appropriate cage 24 can be performed.

Subsequently, the image processing apparatus 30 performs extraction processing of the lubricant region 243 in the specified second inspection region (step 40).
Specifically, the image processing apparatus 30 captures an image so that the black region and the purple region are converted to black, and the blue region and the red region are converted to white with respect to the second inspection region or the region including the second inspection region. The brightness, saturation, and hue of each pixel are adjusted and binarized.
In the present embodiment, the purple region (mixed color region) in the cage 24 is converted to black, and the lubricant region 243 in the cage 24 is converted to white. That is, the saturation, brightness, and hue of the color information are adjusted (designated) so that only the lubricant region 243 is extracted.

Next, a specific example of the extraction process of the lubricant region 243 in the second inspection region performed in the image processing apparatus 30 will be described.
Here, a case where a small amount of lubricant is applied as shown in FIG. 8A and a case where an appropriate amount of lubricant is applied as shown in FIG. 9A will be described.
FIG. 8B is a diagram illustrating an example of a captured image when a small amount of lubricant is applied.
FIG. 9B is a diagram illustrating an example of a captured image when an appropriate amount of lubricant is applied.
As shown in FIG. 8B and FIG. 9B, the region where the lubricant is applied in the cage 24 emits fluorescence upon receiving ultraviolet light and appears in blue, and the lubricant in the cage 24 The area where no is applied is reflected in purple due to the color mixture of excitation light by ultraviolet light and the back illumination 15 (red light).

Then, color adjustment and binarization processing are performed on the captured image so that the purple region is converted to black and the lubricant region 243 is converted to white, whereby FIGS. 8B and 9B are performed. The captured images shown are converted into binarized images shown in FIGS. 8C and 9C, respectively. Note that the identified second inspection region is indicated by a broken line portion in FIGS. 8C and 9C.
The image processing apparatus 30 extracts a white region, that is, a lubricant region 243 from the second inspection region on the specified holder 24 in the binarized image. For example, a white region in the second inspection region is extracted from the binarized images as shown in FIGS. 8C and 9C, and the area is calculated.

Returning to the description of the flowchart of FIG. 5, the image processing apparatus 30 compares the area value of the extracted white region (lubricant region 243) with the area value of the second inspection region, and based on the comparison result, the lubricant. The application state is determined (step 41). The determination process of the lubricant application state is performed on the second inspection region in all the lubricant reservoirs 242.
Then, the image processing device 30 calculates the ratio of the black region (lubricant region 243) to the second inspection region (broken line region), and compares the calculated result with a preset appropriate reference range. .

For example, as illustrated in FIG. 9C, the image processing apparatus 30 determines that the lubricant application state in the cage 24 is good when the calculated result is within the appropriate reference range. On the other hand, as shown in FIG. 8C, when the calculated result is out of the proper reference range, it is determined that the lubricant application state in the cage 24 is defective.
When the calculated result is larger than the upper limit of the appropriate reference range, the image processing apparatus 30 determines that the lubricant application state in the cage 24 is excessive (excess), and the calculated result is the appropriate reference. When it is smaller than the lower limit of the range, it is determined that the lubricant application state in the cage 24 is too small.
Then, after the determination of the application state of the lubricant is completed, the lubricant inspection device 1 moves the transport pallet 17 to the lubricant failure discharging device 47 (FIG. 1) in the next process (step 42), and one bearing 2 The lubricant inspection process for is completed.

The lubricant inspection apparatus 1 can appropriately inspect (determine) the application state of the lubricant on the bearing 2 by performing the above-described inspection process.
In the present embodiment, the amount of lubricant contact with the ball 23 (or the presence or absence of lubricant adhesion) is detected based on one imaging process, that is, one color captured image, and the cage 24 is detected. The application state of the lubricant in the (lubricant reservoir 242) (for example, a large amount, a small amount, an appropriate amount, or nothing at all) can be detected.

According to the present embodiment, by using a color captured image, the color difference between the mixed color region of the excitation light by the ultraviolet light and the back illumination 15 (red light) and the region that emits the fluorescence upon receiving the ultraviolet light is different. Based on this, it is possible to easily distinguish between the lubricant region 243 in the cage 24 and the region in which no lubricant is present, so that the application state of the lubricant in the cage 24 can be easily inspected. Further, it is possible to determine the adhesion state of the lubricant on the ball 23 without accompanying another captured image (imaging process).
In other words, according to the present embodiment, by using the color information of the captured image, that is, by simply setting the color extraction, the lubricant can be applied to both parts of the ball 23 and the holder 24 ( Adhesion) situation can be detected by one imaging process. This makes it possible to shorten the inspection time, that is, improve the work efficiency, as compared with the conventional inspection method that is accompanied by the two imaging processes described in Patent Document 2.
Further, as compared with the conventional structure in which two types of light sources are arranged in the same direction when viewed from the specimen (bearing 2), not only a mechanism for attaching a reflecting plate is required, but also a small light source is used. Therefore, the lubricant inspection apparatus 1 can be downsized.

Further, by specifying the inspection area in detail, it is possible to inspect the more detailed application state of the lubricant. For example, the inspection of the application amount and the application position of the lubricant is executed for each injection location.
By using the LED as the light source, there is no need to adjust the light amount due to deterioration over time or replace the light bulb, and maintenance for the light amount is not necessary. Furthermore, each parameter (for example, reference image data, threshold value, etc.) in the image processing apparatus 30 and the amount of illumination light from the light source are converted into data, which can be easily stored and restored. 30 and the maintenance property in the failure of illumination etc. can be improved.
Support for products with different lubricant application methods (methods) can be achieved by simply changing each parameter (for example, reference image data, threshold value, etc.) in the image processing apparatus 30 and the amount of illumination of the light source.

In the present embodiment described above, visible light is emitted from the back illumination 15 disposed on the back surface of the bearing 2, and ultraviolet light is irradiated from the ultraviolet light illumination 16 disposed above the bearing 2. Yes. However, the arrangement method of the light source for irradiating ultraviolet light and visible light in the lubricant inspection apparatus 1 is not limited to this. The light source of visible light and ultraviolet light may be disposed at a position where the light beam can be irradiated from the opposite direction to the bearing 2 to be inspected.
For example, a reflection plate configured to irradiate the bearing 2 with reflected light may be disposed on the back surface of the bearing 2, and visible light may be irradiated from the back surface of the bearing 2 through the reflection plate. Good. When such a reflector is used, the visible light source can be disposed in the ultraviolet light source, or can be disposed in a region outside the bearing 2. However, when even a part of visible light irradiated from the light source is directly irradiated onto the bearing 2, the influence of the reflected light appears in the captured image. Therefore, in this case, the visible light is irradiated to the bearing 2 only from the back surface through the reflector, that is, the visible light is not irradiated to the bearing 2 from the same direction as the ultraviolet light as necessary. A light shielding structure (such as a light shielding plate or a light shielding curtain) is provided.

FIG. 10 is a diagram illustrating an example of inspection result data in the lubricant inspection apparatus 1.
As shown in FIG. 10, as an inspection result in the lubricant inspection apparatus 1, for example, the area value of the lubricant application area detected at the application positions 1 to N and the non-application positions 1 to N, and the detected rotation direction. An angle (rotation direction detection), a determination result, an NG determination factor, a determination condition, and the like are transmitted to the control device 60.
In the present embodiment, the determination result and the cause of the NG determination are specified in the image processing device 30 of the lubricant inspection device 1. However, even if these items are specified in the control device 60 based on the inspection result. Good. By performing the specific processing in the control device 60, the load on the image processing device 30 can be reduced.
In the example shown in FIG. 10, the area value of the lubricant application region at each application position 1 to N is in the range of 40 to 50, and the area of the lubricant application region at each non-application position 1 to N. When the value does not exceed 0, it is determined to be a non-defective product (OK).
In addition, application | coating positions 1-N show the 2nd test | inspection area | region in the holder | retainer 24 shown with the broken-line part of FIG.8 (c), and non-application | coating positions 1-N show with the broken-line part of FIG.7 (c). The 1st test | inspection area | region in the ball | bowl 23 is shown.

As shown in FIG. 10, in this embodiment, when no lubricant application area is detected at any of the application positions 1 to N and the non-application positions 1 to N, the result is “NG” due to “no lubricant”. Judge that there is. Further, when the application area of the lubricant at the application positions 1 to N is less than 40, it is judged as defective (NG) because “the lubricant is small”, and the application area of the lubricant at the application positions 1 to N is 50. If it exceeds, it is judged as defective (NG) because of “a lot of lubricant”.
In addition, when all the lubricant application areas at the application positions 1 to N are extremely small, and the lubricant application areas are detected at the non-application positions 1 to N, it is defective (NG) due to “position shift”. to decide. The “positional deviation” indicates a rotational positional deviation of the nozzle in the lubricant application device 46.
Further, the area value of the lubricant application region at each of the application positions 1 to N is in the range of 40 to 50, and the area value of the lubricant application region at any of the non-application positions 1 to N is 0. When it exceeds, it is judged as defective (NG) because of “overhang”. The “extrusion” is caused by a dripping phenomenon that occurs when the movement of the transport pallet 17 by the pallet transport conveyor 19 is started within the lubricant application time in the lubricant application device 46.

Next, details of feedback control of the lubricant application device 46 performed in the process of step 19 in the flowchart of FIG. 3 will be described.
FIG. 11 is a diagram showing the content of feedback control instructions to the lubricant application device 46 when the lubricant application state inspection is not passed.
As shown in FIG. 11, for example, when “no lubricant” is determined to be defective (NG), and the number of times “no lubricant” has been detected so far is less than a predetermined number (n times), control is performed. The apparatus 60 sets the application time longer by a predetermined time, and gives an instruction to the lubricant application apparatus 46 to increase the application pressure (pressure applied to the injection nozzle) by a predetermined value. The number of times shown here indicates the number of counts after starting the lubricant application device 46 or after returning the lubricant application device 46.

As shown in FIG. 11, when it is determined that a failure (NG) is caused by “less lubricant” and the number of times “less lubricant” is detected to date is less than a predetermined number (n times), the control device 60 Then, the lubricant application time is set longer by a predetermined time, and an instruction to increase the application pressure by a predetermined value is issued to the lubricant application device 46.
If the number of times that “large amount of lubricant” is determined to be defective (NG) and the number of times that “large amount of lubricant” has been detected to date is less than the predetermined number (n times), the control device 60 sets the application time to the predetermined time. An instruction to reduce the application pressure by a predetermined value is issued to the lubricant application device 46.
When it is determined as defective (NG) due to “position deviation” and the number of times “position deviation” has been detected so far is less than a predetermined number (n times), the control device 60 causes the nozzle head in the lubricant application device 46 to Is instructed to rotate by a predetermined angle.

Here, an example of a method for calculating the rotation angle of the nozzle head in the lubricant application device 46, that is, the correction angle of the nozzle head will be described.
FIG. 12 is a diagram for explaining a method for calculating the correction angle of the nozzle head in the lubricant application device 46.
The rotation angle (correction angle) of the nozzle head in the lubricant application device 46 is calculated based on the following equation, for example.
Rotation angle = (average lubricant application amount / non-application position area) × (360 ° / number of balls) × ratio γ
However, in the above formula, “average lubricant application amount” indicates the average value of the area of the lubricant application region at the non-application positions 1 to N. “Non-application position area” indicates the non-application positions 1 to N, that is, the area value of the inspection region in the ball 23. “Number of balls” indicates the number of balls 23 arranged on the bearing 2.
“Ratio γ” represents a ratio (ratio) of the balls 23 in the circumferential direction of the bearing 2 and is represented by α / β. Here, α indicates an angle occupied by one ball 23 as shown in FIG. 12, and β indicates an angle obtained by dividing 360 ° by the number of balls 23 arranged on the bearing 2.

In the present embodiment, the plurality of nozzles in the lubricant application device 46 are fixed in advance with the positions of all the nozzles arranged in the circumferential direction, but the nozzle arrangement method is not limited to this. Absent. For example, each nozzle may be arranged in an independent state. When arranged in this way, each nozzle can be individually controlled, so that the application position of the lubricant is corrected for each application position 1 to N based on the inspection result of the lubricant inspection apparatus 1. Can do.
In the present embodiment, each time a lubricant application failure is detected, the set value of the lubricant application device 46 is corrected (adjusted) based on the inspection result of the lubricant inspection device 1. The timing at which the inspection result of the lubricant inspection device 1 is fed back to the lubricant application device 46 is not limited to this. For example, when starting the bearing production line, the initial set value of the lubricant application device 46 may be changed (adjusted) based on the inspection result in the previous production lot.
As described above, according to the present embodiment, the lubricant application condition (setting condition) in the lubricant application device 46 can be automatically corrected based on the inspection result of the lubricant inspection device 1. Thereby, since the occurrence of defective application of the lubricant can be reduced, the yield rate in the bearing production line can be appropriately improved.

Returning to the description of FIG. 11, when it is determined that the defect is “NG” due to “overflow” and the number of times “excess” has been detected so far is less than the predetermined number (n times), the control device 60 determines whether the pallet transfer conveyor The 19 drive device is instructed to set a longer waiting time until the start of transport of the transport pallet 17 after applying the lubricant by a predetermined time.
Further, the control device 60 issues an instruction to turn on the yellow indicator lamp to the display device 52 when the number of times of detection of the factor (such as “low lubricant” or “high lubricant”) is less than n times.
When the number of detected factors reaches n times, the control device 60 issues an instruction to stop the lubricant application operation to the lubricant application device 46, and instructs the indicator to turn on the red indicator lamp. The display device 52 is instructed to display a message for prompting inspection confirmation.

As described above, in the present embodiment, when a lubricant application failure is detected in the lubricant inspection device 1, the lubricant application failure is detected to the operator of the bearing manufacturing line by the indicator lamp or the display device in the display device 52. The occurrence can be visually recognized.
Further, a display device similar to the display device 52 is provided in the lubricant inspection device 1, and when a lubricant application failure is detected, the lubricant inspection device 1 side also provides the lubricant to the operator via this display device. You may make it recognize visually that the coating defect of this was detected. In this case, the display device provided in the lubricant inspection device 1 displays information such as the pallet number 70 of the bearing 2 in which application failure is detected and the cause of failure (NG) determination. Thereby, the operator can confirm quickly the bearing 2 from which the application | coating failure was detected.

It is the figure which showed schematic structure of the bearing manufacturing line. (A) is the figure which showed schematic structure of the bearing, (b) was the figure which showed the cross section in the AA 'part shown to (a), (c) showed schematic structure of the holder | retainer. It is a perspective view. It is the flowchart which showed the procedure of the manufacturing process of the bearing in a bearing manufacturing line. It is the figure which showed schematic structure of the lubricant test | inspection apparatus. It is the flowchart which showed the procedure of the process which test | inspects the application state of the lubricant in a lubricant inspection apparatus. It is the figure which showed an example of the captured image. It is a figure for demonstrating the image processing in case the lubrication agent is apply | coated on the ball | bowl. It is a figure for demonstrating the image process in case a small amount of lubricants are apply | coated. It is a figure for demonstrating the image processing in case the appropriate quantity of lubricant is apply | coated. It is the figure which showed an example of the data of the test result in a lubricant test | inspection apparatus. It is the figure which showed the instruction | indication content of the feedback control to the lubricant application apparatus in the case of not passing the inspection of the application state of a lubricant. It is a figure for demonstrating the calculation method of the correction angle of the nozzle head in a lubricant coating device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lubricant inspection apparatus 2 Bearing 11 Camera 12 Lens 13 Sharp cut filter 14 Shading hood 15 Back illumination 16 Ultraviolet light 17 Transport pallet 19 Pallet transport conveyor 21 Outer ring 22 Inner ring 23 Ball 24 Cage 30 Image processor 41 Inner ring supply apparatus 42 Outer ring supply device 43 Ball supply device 44 Ball distribution device 45 Cage assembly device 46 Lubricant application device 47 Lubricant defective discharge device 48 Torque inspection device 49 Acoustic inspection device 50 Defect discharge device 51 Non-defective product collection device 52 Display device 60 Control Device 70 Pallet number 241 Pocket 242 Lubricant reservoir 243 Lubricant area

Claims (6)

A fluorescent component in a rolling bearing having an outer ring, an inner ring, a plurality of rolling elements disposed between the outer ring and the inner ring, and a cage that separates the rolling element and has light permeability. An inspection device for inspecting the application state of a lubricant,
A first light source that emits visible light;
A second light source that emits ultraviolet light;
An imaging unit that captures a color image of the rolling bearing to be inspected from the irradiation side of the ultraviolet light in a state in which the visible light and the ultraviolet light are respectively applied to the rolling bearing to be inspected from the opposing direction;
First inspection area specifying means for specifying a first inspection area for the rolling element from a captured image captured by the imaging means;
First inspection means for inspecting the adhesion state of the lubricant in the first inspection region based on at least one of color information and luminance information of the captured image;
Second inspection area specifying means for specifying a second inspection area for the cage from the captured image;
In the captured image , the color mixture region between the excitation light by the ultraviolet light and the visible light, and the lubricant application region based on the color difference between the lubricant emission region, based on the detection result , Second inspection means for inspecting the application state of the lubricant in the second inspection region;
An inspection apparatus comprising: Coordinate recognition means for recognizing the coordinates of the vertex of the rolling element in the captured image,
On the basis of the vertex coordinates of the recognized rolling elements, the inspection apparatus of claim 1 Symbol placement and identifies at least one of the first test area and the second inspection area. In an inspection apparatus comprising a first light source for irradiating visible light, a second light source for irradiating ultraviolet light, and a color image imaging means, an outer ring, an inner ring, and an outer ring, disposed between the outer ring and the inner ring An inspection method for inspecting the application state of a lubricant having a fluorescent component in a rolling bearing provided with a plurality of rolling elements and a cage having light transmittance that separates the rolling elements,
A first step of capturing a color image of the rolling bearing to be inspected from the irradiation side of the ultraviolet light, with the visible light and the ultraviolet light being irradiated to the rolling bearing to be inspected from opposite directions, respectively;
A second step of identifying a first inspection region for the rolling element from the captured image captured in the first step;
A third step of inspecting the adhesion state of the lubricant in the first inspection region based on at least one of the color information and the luminance information of the captured image;
A fourth step of identifying a second inspection region for the cage from the captured image;
In the captured image , the color mixture region between the excitation light by the ultraviolet light and the visible light, and the lubricant application region based on the color difference between the lubricant emission region, based on the detection result , A fifth step of inspecting the application state of the lubricant in the second inspection region;
An inspection method characterized by comprising: An assembling apparatus for assembling a rolling bearing including at least an outer ring, an inner ring, a plurality of rolling elements, and a cage having optical transparency;
A lubricant application device for applying a lubricant to a predetermined position of the assembled rolling bearing;
An inspection device for detecting the application state of the lubricant in the rolling bearing coated with the lubricant;
A rolling bearing manufacturing apparatus comprising:
3. The rolling bearing manufacturing apparatus according to claim 1, wherein the inspection apparatus is the inspection apparatus according to claim 1. The rolling bearing manufacturing apparatus according to claim 4, wherein the lubricant application device adjusts a lubricant application position based on an inspection result in the inspection device. An eleventh step of assembling a rolling bearing including at least an outer ring, an inner ring, a plurality of rolling elements, and a light-transmitting cage;
A twelfth step of applying a lubricant to a predetermined position of the assembled rolling bearing;
A thirteenth step of detecting a lubricant application state in a rolling bearing coated with the lubricant by the inspection method according to claim 3 ;
And a fourteenth step of adjusting the lubricant application position based on the detection result of the lubricant application state in the thirteenth step,
In the twelfth step, the lubricant is applied at the application position adjusted in the fourteenth step.

Images