US3601616A

US3601616A - Method and device for inspecting bottle by radiant energy

Info

Publication number: US3601616A
Application number: US795229*A
Authority: US
Inventors: Takuma Katsumata; Hisao Kishigami
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 1968-02-02
Filing date: 1969-01-30
Publication date: 1971-08-24
Anticipated expiration: 1988-08-24
Also published as: GB1246561A; JPS4837630B1; DE1905050A1; DE1905050C3; DE1905050B2

Abstract

A method of inspecting bottles comprises directing diffused light rays on bottles to be inspected and scanning the bottles thus irradiated. The bottles, in each of which an optical system with a light receiving unit is inserted, are rotated for scanning. A device for inspecting bottles is provided with a rotary turret, on which a plurality of bottle supports are rotatably and vertically movably arranged at regular angular intervals, irradiating units, optical systems with light receiving units arranged so as to enter into the bottles, and transducers for converting light signals received by the optical systems into electrical signals. The use of diffused light rays makes it possible to eliminate the lens action of the bottle wall and to detect solely foreign particles or substances attached on the bottle walls.

Description

United States Patent 3,411,009 11/1968 Ford et a1.

In entors Takuma Katsumata Primary Examiner-Walter Stolwein Attorney-McClew and Toren ABSTRACT: A method of inspecting lbottles comprises directing diffused light rays on bottles to be inspected and scanning the bottles thus irradiated. The bottles, in each of which an optical system with a light receiving unit is inserted, are rotated for scanning.

A device for inspecting bottles is provided with a rotary turret, on which a plurality of bottle supports are rotatably and vertically movably arranged at regular angular intervals, irradiating units, optical systems with light receiving units arranged so as to enter into the bottles, and transducers for converting light signals received by the optical systems into electrical signals. 1

The use of diffused light rays makes: it possible to eliminate the lens action of the bottle wall and to detect solely foreign particles or substances attached on the bottle walls.

PATENTED W624 197:

SHEET 02 [1F 10 ram PATENTED auszmsn 3,601. 616

sum 03 0F 10 PATENTEU M1824 I97! SHEET 05 0F 10 AMPL SCHMIT CKT 87f MEMOR CKT SIG TRANSFERRINQ ELEMENT REC PATENTEU M1824 I9?! SHEET 08 HF 10 Pmmmuszmn 3,601,616

SHEET [18 HF 10 sum 10 HF 1 FIG.

BACKGROUND @lF THE lhlVlihl'flOhl The present invention relates to a method and a device for inspecting bottles adapted to detect optically foreign particles or substances attached on the walls of bottles for cooling drinks, wine, milk, or the like.

in a conventional device for inspecting bottles, light rays are directed on first sides of rotating bottles to be inspected and received at light receiving devices on the other sides of said bottles. The reduction of a light quantity transmitted through the bottle, due to foreign particles or substances attached on the wall thereof, is detected at the light rece ving device, and the faulty bottles are removed in response to a signal from the receiving device.

in such a conventional device in which the transmitted light quantity is detected, when bottles whose inner and outer sun faces are formed unevenly or printed with figures, trademarks, or the like, the light quantity received at the receiving device, although foreign particles or substances are not attached on the surfaces of the bottles, changes owing to the lens action due to the uneveness of bottles or the light absorption in the prints, whereby the clean bottles are liable to be removed which results in an imperfect inspection of bottles.

OBJECT OF THE llhlVlEhlTlOl l In accordance with the invention, diffused light rays are directed on bottles to be inspected each placed at a certain position, and optical systems inserted in the respective bottles scan the bottles while relative rotation is effected between the optical systems and the respective bottles. liccause diffused light rays are directed on bottles from the outsider; thereof,

although the surfaces of the bottles are formed uneven r lens action due to the uneveness can be eliminated so that the diffused light rays can be uniformly transmitted into the hottles. Since scanning of the bottles is carried out while the optical systems and bottles are rotated relative to each other, the

light rays can be uniformly received by the optical systems rc- J gardless of the uneveness of the bottles. The npti systems detect foreign particles or substances attached on the bottles and which have shielded the diffused light rays, whereby the foreign particles or substances can be surely detected.

in accordance with another aspect of the invention, the diffused light rays are directed on bottles to be inspected each in rotating motion at a certain position and then reflected by diffusing reflecting members arranged opposite to sources for the diffused light rays through interposition of said bottles, the reflected light rays being scanned by optical systems which are inserted in the bottles so as to face the diffusing reflecting members. Thus, the bottles having uneven surfaces can be inspected as in the case where the diffused light rays impinge directly on the bottles. lvloreover, although bottles to be inspected are provided with prints, the influence of light-shieldlng caused by the printed portions can be eliminated, and the foreign particles or substances can be detected by the use of irradiating light rays having a suitable wave length and of reflecting members having an adequate reflection factor in order that the sum of the quantity oflight rays which fall upon Lit the optical system after having been reflected on the diffusing reflecting members and then transmitted through the printed portions on the bottles and the quantity of light rays which fell upon the optical systems after having been transmitted through the walls of the bottles and reflected on the printed portions may become equal to the quantity of light rays which fall upon the optical systems after having been transmitted through the transparent portions of the bottles without prints.

in accordance with a further aspect ofthe invention, bottles to be inspected are transferred onto a plurality of bottle sup ports installed on a rotary turret, and said bottles are rotated and moved upwards and downwards while being irradiated with diffused light rays on the turret. Optical systems inserted in the respective bottles in motion scan the bottles for detect ing foreign particles or substances, the optical detecting signals from the optical systems being converted into electrical signals which are utilized to remove only faulty bottles having foreign particles or substances adhered thereto. Since the bottles are scanned for detecting foreign particles or substances in the state described above, not only bottles having smooth surfaces but also bottles having uneven surfaces can be inspected, while the lens action due to the uneven portions of the bottles is eliminated so that the inspection of a large number of bottles can be continuously carried out with a high efficiency. Moreover, the faulty bottles can be automatically selected by converting the optical detecting signals from the optical systems into electrical signals and removing only faulty bottles with the foreign particles or substances attached thereon in response to said electrical signals. Furthermore, the accuracy of detection for foreign particles or substances can be greatly improved by making narrow the range for receiving light of the optical system.

in accordance with a further aspect of the invention, a bot tlc inspection device is provided with at least one diffused light source for irradiating each bottle to be inspected placed at a certain position, an optical system inserted into the bottle and a driving mechanism for rotating the bottle and/or the optical system thereby providing relative rotation thcrebetween. :fhus, foreign particles or substances adhere on bottles, through the bottles have uneven portions, can be surely detected while eliminating the lens action due to said uneven portions.

in accordance with another aspect of the invention, a bottle inspection device comprises a turret mechanism provided with a plurality of bottle supports, transferring means for delivering bottles to the turret mechanism or accepting them from the turret mechanism, lifting and rotating mechanisms for the rcsp ctive bottle supports, at least one diffused light source for irradiating each of the bottles on the supports, an optical system inserted into one of the bottles, and a control means for converting an optical signal generated at the optical system in JEPGUSQ to the existence of foreign particles or substances on the bottles into an electrical signal and transmitting an instruction signal for taking away faulty bottles from the main ron c to a faulty bottle carryout mechanism. This construction makes it possible to continuously and efficiently inspect a large number of bottles and to automatically select and remove only bottles having foreign particles or substances adhercd thereto.

The invention will be more fully understood from the following detailed description of preferred embodiments taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

idliiElF DESCillPTlUhl OF THE DRAWENGS in the drawings:

lFllG. ii is a schematic plan view illustrating a bottle detecting device embodying the present invention;

lFiG. If is an enlarged plan view of a part of HG. ll;

lFlG. It is a vertical sectional view taken along the line Illill of MG. 2

MG. l is a vertical sectional view ofthe turret mechanism in Flt]. l;

FIG. 5 is a plan view of the upper portion of the turret in :IG. 1;

FIG. 6 is a plan view of a part of an alternative form of the turret mechanism;

FIG. 7 is a schematic sectional plan view illustrating the flow of bottles in the turret mechanism;

FIG. 8 is a diagram for explaining the principle of bottle inspection;

FIG. 9 is a horizontal sectional view of a detecting part;

FIG. 10 shows an image of a foreign particle or substance detected by an optical system;

FIG. 11 is a diagram for explaining the function of a reticule;

FIG. 12 is a development view showing the turret mechanism operating in engagement with cams;

FIG. 13 is a perspective view of a driving gear mechanism;

FIG. 14 is a vertical view, partly in section, of an alternative form of the bottle mouth holding mechanism;

FIG. 15 is a vertical view, partly in section, of the lifting mechanism for a bottle mouth holding bracket;

FIG. 16 is a horizontal sectional view taken along the line XVIXVl ofFIG. 15;

FIG. 17 is a vertical view, partly in section, of an alternative form of the bottle support braking mechanism;

FIG. 18 is a plan view of an alternative form of the bottle guide mechanism; and

FIG. 19 is a vertical sectional view taken along the line XlX--XEX of FIG. 18. DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to FIG. 1, the reference character A denotes a device for inspecting bottles according to the invention. Bot' tles are fed from a bottle washing machine B to the bottle inspecting device A by means ofa conveyor C, where faulty bottles containing foreign particles or substances adhere thereto are selected to be removed, while clean bottles are sent to a bottling machine D and automatically bottled.

Referring at first to FIGS. 2 to 3 and FIGS. 8 to 10, the principle of inspecting bottles with a surface formed unevenly or printed, for example, Coca Cola (trademark) bottles will be described. Bottles 1 to be inspected are so arranged as to be rotated and at the same time moved vertically as they are put between bottle supports 2 and bottle mouth holders 3 arranged respectively at regular angular intervals on the outer periphery ofa rotary turret so as to face each other in the vertical direction. Inner surface inspecting mirrors 4, which are vertically fixed on the turret, are arranged so as to be removably inserted into the bottles through the bottle mouth holders 3.

The reference numerals 5 denote a .plurality of irradiating nits, which are fixed along the outer periphery of the turret and each comprises a light source lamp 5a, a casing 5b for housing the lamp 5a and a screen made of opal glass fitted on the from surface of the casing. The light rays emitted from the lamp 5a become nonoriented diffused light rays after passing through the screen 50. In order -0 increase the degree of diffusion of the light rays, a diffusion lens (not shown) may preferably be arranged between each lamp 5a and screen 50. Semicylindrical reflecting plates 6 are installed at the positions nearer to the center of the turret than the bottles 1 held by the bottle supports 2 so as to face the irradiating units 5, respectively. Each reflecting plate 6 consists of a conventional mirror coated on its rear side with a metal such as silver or aluminum by vacuum evaporation and a protective layer thereon, and is laminated on its surface with a milk-colored glass having a good diffusing character, such as opal glass, so that the incident light rays on this reflecting plate may be diffusely reflected.

Furthermore, each inner surface inspecting mirror 4 is composed of a prism 4a so arranged at the lower end thereof as to face the center of the turret in the angular range of 6, a diaphragm 4b arranged close to the prism 4a and three lenses 40 arranged at a predetermined interval in the vertical direction, and is capable of receiving light rays in the angular range m, as shown in FIG. 8. The light rays irradiated from the unit 5 and reflected by the reflecting plate 6 are now nonoriented diffused light rays, so that, although the light rays passing the sidewall 1a of the bottle 1 having the uneven outer surface are refracted, owing to the uneveness of the surface, like a lens, the light rays falling upon the bottle wall la are still nonoriented. Thus, the lens action of the bottle wall is eliminated, and the light quantity to be received is uniformly distributed on the inner surface inspecting mirror 4.

Further, although the surface of the wall 10 of each bottle 1 is printed with white-colored letters lb, trademarks. or the like, the light shielding effect due to the printed portion lb can be eliminated. For this purpose, the wavelength distribution of light rays irradiated from the irradiating unit 5 is appropriately selected, and the diffusing layer of the reflecting plate 6 has the same white color as the print lb while the reflection factor of the reflecting plate 6 is selected to a proper value. Thereby the sum of the light quantity x, of light rays X falling upon the inner surface inspecting mirror 4 after having been irradiated from the irradiating unit 5, diffusely reflected by reflecting plate 6 and then transmitted through the printed portion lb of the bottle wall 1a, and the light quantity y of, light rays Y falling upon the mirror 4 after having been irradiated from the irradiating unit 5 and passed twice through the wall la of the bottle and reflected on the printed portion lb, is made equal to the light quantity 1, of light rays 2 falling upon the mirror 4 after having been irradiated from the irradiating unit 5, diffusely reflected by reflecting plate 6 and then passed through the unprinted transparent portion of the bottle wall In, as shown in FIGS. 8 and 9.

Assuming that L is the brightness of light rays irradiated from the irradiating unit 5, a is the reflection factor of the reflecting plate 6, ,8 is the reflection factor of the printed portion lb on the bottle wall la, 'y is the transmission factor of the printed portion lb, and 5 is the transmission factor of the glass of the bottle wall In, then the light quantity x transmitted through the printed portion Ibis:

x=L-oz-y-8-, and the light quantity y reflected on the printed portion lb is:

aa Moreover, the light quantity z transmitted through the transparent portion without prints is:

z=L6- 016 Accordingly, from the relation z=x+y,the reflection factor a of the reflecting plate 6 is given as follows:

If a reflecting plate 6 having such a reflection factor a is employed, the influence of light-shielding due to the printed portion on the bottle wall la can be entirely eliminated.

When foreign particles or substances adhere to the bottle wall la, the above relation at the printed portion 1b no longer holds, and the light quantity received on the inner surface inspecting mirror 4 changes so that the adherence of foreign particles or substances can be detected.

The structure of the bottle inspecting device A will now be explained in detail. In FIG. 4 showing the turret mechanism, a hollow shaft 10 is rotatably in bearings 9 on a stationary central shaft 8 vertically fixed on a foundation 7. Flanges ll, 12 are fltted unitarily on the upper end and the lower end, respectively, of the hollow shaft 10. A ring gear 13 is provided on the outer periphery of the lower flange 12, so that the flanges ll, 12 are rotated about the central shaft 8 by a driving mechanism (not shown) in engagement with the ring gear 13. Vertical guide rods 14, whose opposite ends are fitted in the flanges 11 and 12, are arranged at regular angular intervals, and outer guide rods 15 are fixed in vertical planes passing through the guide rods 14 and the axis of the turret and on a outer circle concentric with the circle on which the rods 14 lie.

On each of the outer guide rods 15, there are slidably fitted and serially arranged a bottle mouth lifting tube 16 and a bottle support lifting tube 17. The lifting

tubes

16, 17 are provided with cam followers l8, 19, respectively, which are in engagcment with cam slots 24ft, Illll, having the contours shown in the development view of lFlG. ill, on the outer periphery of the foundation l, and move upward and downw with rotation of the turret.

At the upper portion of each bottle mouth lifting tube il there is mounted, for relative vertical movement, a bottle mouth bracket 1h, compression spring ihturpiuiett between an adjusting member 1.3, screwed into the lower end of the bracket Ml, and a ring il l, fitted on the upper end otthe lifting tube the A bottle mouth holder l l t mou .d on the bracket through a bearing that, when the mouth holder fl abuts the mouth the bottle it upon downward movement of the bottle mouth lifti t? i the 3 is displaced upwards with respect to the bottle llltin tube llti clue to the bias of the spring whereby the bot l may he port lifting rod 239 independently of the vertical movement of A the rod 129.

A brake rotor I'll; is fired on the bottle support lilting rod flit as one body, and a brake stator is installed on loosely fitted on the bottle support lifting rod and at same time biased onto the lower flange ill through a sorir whereby the brake rotor 32, upon downward movement oi the rod 29, is pressed against the brake stator so that the bottle support 2 is bralted to stop together with the bottle support lifting rod 1W.

Furthermore, a bottle guide member movably along bottle mouth lifting tube lid, and between the bottle mouth bracket support bracket A supporting shaft tegral with the bottle guide membe downwards therefrom, and is slidably port bracket E'F. When bracket position as shown at the left of lrlG. Al, the lower supporting shaft it? comes into contact with the ll and, when the bottle support bra position as shown at the right of shaft It? comes into contact wit. to hold the bottle guide member The irradiating unite it are mour dation "i as shown in lFllG the range shown in l' lltfl. on the outer periphery of a suppo t the hollow shaf mechanism.

in MG. '7, a screw conveyor is prov' vcyor t: leading to the bottle w rnachu feed star wheel ilt is arranged facing conve conveyor tC and the flat portion Elna of one of members do lying at the same height, there is cuate supporting plate All, one which a guide vided concentrically with the star .vhec: ll. veyor Elli and the star wheel ill are to .i with the rotation of the turret mec t are held one by one with the bottle guide nu. the same time supported on the bottle sup pi A bottle oudeed star wheel is provided tion of the conveyor t1 leading to the bottling ma v the terminal of the turret mechanism Across the l portion 360 of the bottle guide member .lti and the conveyor C, there is provided a bottle-bottom inspecting device of a lrnown structure. A guide wall d5 similar to the guide wall lftl is also provided. Around the star wheel there are provided suction devices (not shown) which, when foreign particles or subunit it (til l at l t t stances adhered on bottles it are detected by means of the bottlc inner surface inspecting device and the bottle-bottom inspoofing device or, carry away the faulty bottles onto an accuted around the driving pulley fill, the prime mover pulhey i nd the guide pulleys elli, 49, Ml, 5i, and thus the rotatof the pulley t-"/ is transmitted to the driving pulley bottle driving section 53. The extent of the bottle driving section can be adjusted by changing the positions of the guide pulley til, while the tension of the belt 52 can be adjtun. d by changing the position of one or both of the guide pulle, till.

the driving system for the turret mechanism, the screw conand the star wheels dil will be explained with no i to l litl. lit. in series to the output shaft of an electric there are connected reduction gears 55, so and 5'7, and between the

latter gears

5b and 5") there is provided a clutch bral t pinion 5) is fixed on the upper end of the itt the turr" t mechanism. Further, a gear so is fixed on the output shaft [Wu of the reduction gear 57 and drives with gears 6i, oil, on drive shafts i he, Mia of the star wheels til, 43 through int. iediate gears till, st, respectively. It bevel gear us on the star wheel drive shaft Allie is interconnected to the screw conveyor Eli through bevel gears a, s7, till, so and 7h. Thus the star wheels -ltll, and the screw conveyor 39 are driven in syuchronisrn with the turret mechanism.

The driving pulleys Elli mounted in the turret mechanism are rotated with a speed corresponding to the sum of the speed of driven by the prime mover pulley 4"), and the iheral speed of the rotating turret mechanism so that, in rte the bottles l at a constant speed by the driving independently of the rotating speed of turret is necessary only to provide differential gear rich drives a prime mover pulley l? at a speed corrig to the difference between the speed of the output Jun ofthe reduction gear 55:, rotated at. a constant speed, that of the gear as intermittently rotated by the clutch the input bevel gear "lie of the differential gear 1 on the output shaft 55 5a of the reduction gear the output bevel ge r Ill/J is fixed on the shaft lla of the mover pulley -tll. Etoth planetary bevel gears 71c it with the input and output bevel gears 'illa, lib are lv mounted in a gear casing "lid. A bevel gear "lie is .dly on shaft and drives gear oil of the star rough a gear 7%.

opes of the cam slots lift, 7 l for lifting the bottle tubes to and the bottle support lifting tubes 17 lifting cam slot Tell lies at the lowermost position imy after the angular position 73 in the plane passing h the axis of the central shaft ll of the turret and the axis at wheel dtli so that the bottle holder fl depresses the 2' bottle ll through the cam follower ill, the bottle hing tube to and the bottle mouth bracket On the the bottle support lifting slot 2i takes a position or than its lowermost position so that the bottle is lifted slightly through the cam follower ll l the tie support lifting tube lli', the bottle support bracket 27 '0 tie support lifting rod 2%. Thus the bottle l is ietween the mouth holder 3 and the bottle supot tit utlv hold 1 then descend suddenly to a horizontal braking section 78, in which the bottle supports are braked to stop. The bottle mouth lifting cam slot 20 ascends suddenly up to the position 79 in the plane passing through the axis of the central shaft 8 of the turret and the axis of the star wheel 40, while the bottle support lifting cam slot 21 descends slightly. Both

cam slots

20, 21 extend horizontally past the position 79, and then upwardly offset. In a predetermined section 80 of the offset route an amplifier checking device, which will be explained later, operates.

To improve the accuracy of detection, the inspecting field m of the inner surface inspecting mirror 4 is selected small. However, if the area of the image 81a of a foreign particle or substance 81 shown in FIG. 10 is small with respect to the area S of the entire field of the inner surface inspecting mirror 4, the signal ratio 'y/S detected by a light receiving element 82 of the mirror 4 is so small that the foreign particle or substance may not be detected. To cope with this, a reticule 83 as shown in FIGS. 10 and 11 is rotated between each mirror 4 and each light receiving element 82. Thus, if the sectional area S of the light flux falling upon the light receiving element 82 is made small, the image 81a of the foreign particle or substance 81, upon rotation of the reticule 83, is shielded by the reticule 83 and appears between its legs so that an output signal having the sine wave form as shown in FIG. 11 is generated at the light receiving element 82. Moreover, the signal ratio detected by the light receiving element 82 becomes (y/S-S'), that is, larger than the signal ratio (y/S), and, therefore, the foreign particle or substance can be more surely detected.

Driving mechanisms 84 for the reticules 83 are shown in FIGS. 5 and 8. Pulleys 84a carrying the reticules 83 are rotatably supported on the support members 84b. Belts 842 are each entrained around the large diameter portion of a stepped pulley 840 on the top of every other guide rod 15, two of the pulleys 84a and a tension pulley 84d. Further a belt 84h is entrained around the small diameter portions of all the stepped pulleys 84c and a pulley 84g of on electric motor 84f (FIG. 4). All the reticules 83 are simultaneously rotated by the motor 84f.

In FIG. 5, each belt 842 is entrained around two pulleys 84a carrying the reticule. However, it may be entrained around three pulleys 84a as shown in FIG. 6.

A hold checking element 85 is provided at the position 74 slightly apart from the position 73 at which the bottle 1 is held, as shown in FIGS. 7 and 12, and a protruding piece 86 is mounted on the upper bracket 22.

When the bottle mouth holder 3 holds the mouth of a bottle 1 at the moment of arrival of bracket 22 at the position 74, the holding of the bottle is confirmed by that the protruding piece 86 cor es into abutment on the hold checking element 85. On the contrary, when the bottle mouth holder 3 holds no bottle mouth 1, the bracket 22 is moved by the force of the spring 25 to move away the protruding piece 86 from the hold checking element 85 so that the nonholding of the bottle is detected. Then, the clutch brake 58 in the driving mechanism in FIG. 13 is actuated to stop immediately the turret.

In the hold checking mechanism described above, the switch of the checking element 85 is closed at every passage of the bottle supports 2, but it remains open in the intermediate state so that a complicated discriminator circuit is additionally required.

If the hold checking element 85 is so arranged below the protruding piece 86 that the protruding piece element 85 only when bottle mouth holder 3 is not holding the mouth of a bottle. whereby the checking element 85 generates a signal only in case of incorrect holding of bottle, the circuit construction for hold checking can be very much simplified.

On the top of the turret mechanism there is provided an amplifier unit 87, as shown in FIG. 4, which consists of an amplifier 87a connected to the output of a photoelectric element 82, a frequency band-pass amplifier 87c connected to the output of the amplifier 87a through a condenser 87b, an element 87d, a Schtnitt trigger circuit 87e provided with a level for separating noise signals, and a memory circuit 87f, as shown in FIG. 8. The frequency band-pass amplifier 87a is provided with an amplification factor regulator 88, and the memory circuit 87fhas a signal transferring element 89. Regulator 88 and element 89 are mounted on a plate 90 comprised by the outer periphery of upper flange ll of the turret. A rotary transformer 91 is provided at the top of the central shaft 8, as shown in FIG. 4, the primary side thereof being fixed on the central shaft 8, while the secondary side is mounted on the upper flange ll of the turret and the electric potential for energizing the motor 84f, for the reticule, and the amplifier unit 87.

In the amplifier checking section shown in FIG. 12, there is provided an amplifier checking mechanism 92 consisting of a lighting device 92a for checking, a very small light shielding piece 921; which generates an output responsive to foreign particles or substances on the bottle wall and a very small light shielding piece 92c responsive to nonexistence of foreign particles or substances of the bottle wall. When the inner surface inspecting mirror 4 faces the light shielding piece 921;, if the amplifier unit 87 operates normally, an output signal appears at the signal transferring element 89, and, if the unit 87 is in trouble, no output signal appears. Further, when the inner surface inspecting mirror 4 faces the very small light shielding piece 920, if the amplifier unit 87 is normal, no output signal 89 appears, and, if the unit 89 is in trouble, an output signal appears. These outputs are discriminated by logic circuits, whereby the operation of the amplifier unit 87 is checked.

A signal receiving mechanism 93 is provided facing the signal transferring plate and adjacent to the very small light shielding piece 92, as shown in FIG. 7. In the lighting section 5 in which the irradiating units 5 irradiate bottles, the foreign particles or substance 81 on bottles 1 are detected by the inner surface inspecting mirror 4 and the light receiving element 82 so that a signal is transmitted to the signal transferring element 89 and then received by the signal receiving mechanism 93. Thus faulty bottles are selected out by the carryout device for faulty bottles provided at the star wheel 43. A checking signal of the amplifier unit 87 detected by the amplifier checking mechanism 92 is also received to energize an indicator (not shown), whereby nonoperation of the amplifier unit 87 can be immediately informed.

The whole device is brought into operation by starting the motor 54 in FIG. 13 and the motor 84f for, reticules, through the rotary transformer 91 in FIG, 4 and energizing the irradiating units 5 and amplifier unit 87.

Upon operation of the infeed star wheel 40 and the screw conveyor 39, bottles 1 are fed one by one to the bottle supports 2 through the fiat portions 36a of the bottle guide members 36, and each held tightly between the bottle support 2 and bottle mouth holder 3 immediately after the position 73 shown in FIG. 7 and 12. The bottles, after inspection of their holding at the position 74, ascend suddenly while each is being held between a bottle support 2 and a bottle mouth holder 3 and being rotated about its own axis by means of the driving belt 52, and go into the lighting section 5 in which the irradiating units 5 operate.

Then, the wall In of each bottle I is scanned helically from its bottom to its top by means of the inner surface inspecting mirror 4 for detecting foreign particles or substances adhered thereon.

When the foreign particles or substances are detected, an output signal is generated at the light receiving element 83, and is amplified and stored in the amplifier unit 87.

The bottle supports 2, after passing the bottle inspecting section 77, the driving section 53 and the lighting section 5', are braked in the braking section 78 to stop. The bottles 1 are transferred from the bottle supports 2 and the flat portions 361: of the bottle guide members 36 to the bottle bottom inspecting device 44.

The signal, which has been sent from the light receiving element 82 in the bottle I held between the bottle supports 2 and the bottle mouth holders 3 and stored in the amplifier unit 87,

is transmitted from the turret mechanism by the signal receiving mechanism 93, so that the faulty bottle is moved away to the table of the accumulator 46 by means of the suction means provided at the outfeed star wheel 43. The faulty bottle, on whose bottom foreign particles or substances are adhered, is, of course, removed by means of the bottom inspecting device 44. Clean bottles without foreign particles or substances are transferred onto the conveyor C. On the other hand, when the inner surface inspecting mirror 4 comes to face the amplifier checking mechanism, it checks whether the amplifier unit 87 operates normally or not, and, if the unit 87 is normal, the operation thereof is carried on while if abnormal, the indicating unit (not shown) acts to stop immediately the device, for the inspection of the faulty part.

In the above embodiment, each bottle mouth holder 3 is so mounted through the bearing 26 to the bottle mouth bracket 22 that it can not be moved in the vertical direction with respect to the bottle mouth brackets 22. However, as shown in FIG. 14, each bottle mouth holder 3 may be rotatably supported in an inner sleeve 102 through axial bearings 101, which sleeve is in turn fitted in the bottle mouth bracket 22 through a slide bearing 103 which is also slidable in the axial direction, and compression springs 104, 105 are interposed between the upper and

lower flanges

102a, 102b of the inner sleeve 102 and the bracket 22, respectively, whereby the bottle mouth holder 3 is not only movable in the vertical direction but also rotatable.

If the bottle mouth holder 3 is vertically movably mounted in the bracket 22 in the above manner, each bottle mouth bracket 22 may be fixed on the bottle mouth lifting tube 16 as a unit therewith, so that the elastic supporting mechanisms 23, 24, 25 in FIG. 4 can be omitted, as shown in FIG. 15. In this case, the clamping portion 22a of the bracket 22 for the bottle mouth lifting tube 16 is split and fastened together by means of bolts and nuts 2211, so that the position in the vertical direction of the bottle mouth support 3 may be easily adjusted. This is particularly effective for inspecting bottles having a different height by a single device.

In the embodiment shown in FIGS. I to 13, the brake rotor 32 is mounted on each bottle mouth lifting rod 29 as one body, while the brake stator 35 is mounted on the carrier 33 through interposition of the spring 34. However a brake rotor 32 may be slidably fitted on the splined bottle mouth lifting rod 29 and biased downwardly by means of a coil spring 34 whose upper end engages a carrier 33 fixed on the rod 29, as shown in FIG. 17. Brake shoes 106 may also be provided on the upper surface of the brake stator 35 and on the lower surface of the brake rotor 32.

Further, the bottle support bracket 27 for each support lifting tube 17 may be formed at its mounting portion 27a in the shape of a cylinder extending downwards, the portion 27a being connected fixedly with the upper end of the bottle support lifting tube 17. A slide ball bearing 107 is provided between the bottle support bracket 27 and the bottle mouth lifting tube 16. Further a slide ball bearing 108 is also provided between the bracket 27 and the guide rod 14. Such a construction permits the bottle supports 2 to move easily and smoothly in the vertical direction.

In place of the massive base portion 36b of each bottle guide member 36, a guide member 109 maybe formed with notches 109a adapted, for insertion of the bottle support 2, and slits 109b opening thereto, adapted to pass the bottle support bracket 27, as shown in FIGS. 18 and 19. Thus, the height of the turret mechanism can be considerably reduced,

What we claim is:

1. A method of inspecting bottles for adherent foreign matter, comprising the steps of directing diffused light rays, from an external light source, laterally through bottles to be inspected; rotating the bottles relative to the light source; diffusely reflecting light rays which have passed through the bottles at locations on the opposite sides of the bottles from the light source; directing the diffused reflected light rays on the bottles; and optically scanning, interiorly of the bottles, the

reflected diffused li ht within the bottles during such rotation, 2. A method 0 inspecting bottles for a herent foreign matter, comprising the steps of moving the bottles in spaced relation along a path of travel while rotating and axially reciprocating the bottles; during travel of the bottles along the path, directing diffused light rays, from an external source of light, laterally through the bottles to be inspected; simultane' ously optically scanning, interiorly of the bottles, the diffused light within the bottles during such rotation and axial reciprocation to provide optical output signals corresponding to the scanned diffused light within the bottles; converting the opti' cal output signals into electrical signals; responsive to the electrical signals, separating bottles having adherent foreign matter from bottles free of adherent foreign matter; diffusely reflecting light rays which have passed through the bottles from locations on the sides of the bottles opposite the light source; directing the reflected diffused light rays on the bottles; and optically scanning the reflected diffused light within the bottles.

3. Apparatus for inspecting bottles for adherent foreign matter, comprising, in combination, at least one external light source; means operable to direct diffused light rays from said source laterally through the bottles to be inspected; at least one optical system insertable into the bottles to optically scan, interiorly of the bottles, the diffused light within the bottles; driving mechanism operable to effect relative rotation of said bottles and said optical system during such optical scanning; and reflecting means positioned on the sides of said bottles opposite said light source and operable to diffusely reflect light rays, which have passed through the bottles, on the bottles; said optical system scanning the reflected diffused light within the bottles.

Claims

1. A method of inspecting bottles for adherent foreign matter, comprising the steps of directing diffused light rays, from an external light source, laterally through bottles to be inspected; rotating the bottles relative to the light source; diffusely reflecting light rays which have passed through the bottles at locations on the opposite sides of the bottles from the light source; directing the diffused reflected light rays on the bottles; and optically scanning, interiorly of the bottles, the reflected diffused light within the bottles during such rotation.

2. A method oF inspecting bottles for adherent foreign matter, comprising the steps of moving the bottles in spaced relation along a path of travel while rotating and axially reciprocating the bottles; during travel of the bottles along the path, directing diffused light rays, from an external source of light, laterally through the bottles to be inspected; simultaneously optically scanning, interiorly of the bottles, the diffused light within the bottles during such rotation and axial reciprocation to provide optical output signals corresponding to the scanned diffused light within the bottles; converting the optical output signals into electrical signals; responsive to the electrical signals, separating bottles having adherent foreign matter from bottles free of adherent foreign matter; diffusely reflecting light rays which have passed through the bottles from locations on the sides of the bottles opposite the light source; directing the reflected diffused light rays on the bottles; and optically scanning the reflected diffused light within the bottles.