WO1999059738A1

WO1999059738A1 - Method of sorting bottles, a sorting apparatus, a sensor and a detector equipment

Info

Publication number: WO1999059738A1
Application number: PCT/FI1999/000435
Authority: WO
Inventors: Teuvo Kolehmainen
Original assignee: Teuvo Kolehmainen
Priority date: 1998-05-20
Filing date: 1999-05-19
Publication date: 1999-11-25
Also published as: EP1079941A1; FI981134A0; FI981134A

Abstract

The invention relates to a method of sorting bottles, a sorting apparatus, a detection method and detection equipment, which are used for detecting bottles. The detector equipment comprises a plurality of detectors (60), each detector comprising one or more measuring rods (21, 31) for each bottle to be detected, each measuring rod comprising a measuring head (22, 32). The detector equipment further comprises means (90) that move each measuring rod (21, 31) in such a manner that the measuring head (22, 32) in each measuring rod travels along the outer surface of the bottle simultaneously measuring the bottle, each bottle being deposited in a crate or arranged into bottle groups.

Description

METHOD OF SORTING BOTTLES, A SORTING APPARATUS, A SENSOR AND A DETECTOR EQUIPMENT

FIELD OF THE INVENTION

The invention relates to a method of sorting bottles, the method being employed in a bottle sorting apparatus.

BACKGROUND OF THE INVENTION

In the prior art systems, bottle shape is detected by determining bottle profiles with a camera scanning a bottle from the side. The bottles are scanned while they pass the camera in a line. Since the bottles are lined up while being detected, the conveyor speed must be high, in which case the bottles easily fall down. If the bottles to be detected are arranged in lines, sorting the bottle types must also be performed while the bottles are lined up. This means that the conveyor conveying lined-up bottles to be detected also has to operate at a high speed to enable the sorting capacity to be sufficiently high. The high conveyor speed, however, causes even more bottles to fall. The prior art sorting apparatuses comprise a plurality of conveyors which, at least to some extent, cause bottle wear while forwarding the bottle lines.

BRIEF DESCRIPTION OF THE INVENTION

An object of the invention is thus to provide a method and an appa- ratus implementing the method to enable the above problems to be solved.

This is achieved with a method disclosed in the introduction, the method being characterized by detecting each bottle such that during the detection, each bottle is measured while deposited in a crate or belonging to a bottle group of a plurality of bottles by one or more measuring rods, each measuring rod having a measuring head of its own, which is moved along the surface of a bottle to be detected, transferring detected bottles of one or more crates or bottle groups to a bottle passage specific to each bottle type, in such a manner that the bottles in the crates or bottle groups are lifted out of the crate or from their carrier and the lifted bottles are conveyed to the bottle passages, and depositing bottles detected to be of a similar type in each bottle passage.

The invention further relates to a sorting apparatus, which is used for sorting bottles and which comprises a conveyor conveying bottles to be sorted. The sorting apparatus of the invention is characterized by the sorting apparatus comprising detector equipment comprising a plurality of detectors, and receiving from the conveyor bottles arranged in crates or bottle groups, and comprising, for each bottle to be detected, one or more measuring rods, each measuring rod comprising a measuring head of its own, which measuring head travels along the surface of a received bottle measuring the bottle, sorting means receiving the bottles detected by the detector equipment, the bottles being transferred, arranged in the crates or bottle groups, to the sorting means, a bottle passage for each bottle type, whereto the sorting means transfer the detected bottles in such a manner that the sorting means lift the bottles of one or more crates or bottle groups received out of the crate or from their carrier, after which the sorting means deposit bottles detected to be of a similar type among the lifted bottles in a bottle passage corresponding to said bottle type. The invention further relates to a detector equipment, which is used for detecting bottles.

The detector equipment of the invention is characterized by the detector equipment comprising a plurality of detectors, each detector comprising one or more measuring rods for each bottle to be detected, each measuring rod comprising a measuring head, and means moving each measuring rod in such a manner such that the measuring head in the measuring rod travels along the outer surface of the bottle simultaneously measuring the bottle, each bottle being deposited in a crate or arranged in a bottle group during the detection. The invention further relates to a detection method, which is used for detecting bottles.

The detection method of the invention is characterized by moving along the outer surface of a bottle to be detected, the bottle being deposited in a crate or arranged in a bottle group during the detection, at least one meas- uring rod's measuring head measuring the bottle's profile while moving along the surface of the bottle, and comparing measurement values obtained from measuring the bottle's profile with previously known reference values, after which the type of the bottle to be measured is determined.

The preferred embodiments of the invention are disclosed in the dependent claims. The idea underlying the invention is that measuring heads are moved along the surface of a bottle to detected, by means of which measuring heads the shape of the bottle is measured, the bottle's shape enabling at least partially the type of the bottle to be determined. The method, apparatus and detector equipment of the invention provide several advantages. The detector equipment enables bottles in a crate or a bottle group to be detected, allowing fast detecting and sorting. The sorting apparatus of the invention can be used for detecting and sorting glass or plastic bottles deposited in the same crate. The method and apparatus are extremely well suited for detecting and sorting plastic bottles since being light, plastic bottles easily tend to fall. The sorting apparatus can employ lower conveying speeds, whereby bottles fall less frequently. The bottles in crates received by the sorting apparatus can be sorted by a sorting apparatus comprising parallel bottle passages, in which case high-speed bottle conveyors become redundant. Furthermore, using a line former is avoided, which means lower investment costs of the sorting apparatus than those of the prior art sorting apparatus.

Since bottles are detected by moving the measuring head along the surface of the bottle, differences between bottle profiles and differences be- tween the outer surfaces of the bottles can be found out, in which case different bottles can be discerned from each other with a great certainty. In addition, the same measuring head is suited for measuring different kinds of bottles.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is now described in closer detail in connection with the preferred embodiments with reference to the accompanying drawings, in which

Figure 1 shows a detector of detector equipment of the invention, Figure 2 shows an embodiment of the detector equipment, Figure 3 shows a sorting apparatus of the invention, Figure 4 shows the structure of a bottle passage.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a detector 60 of detector equipment, which detector is used for detecting bottles 10. The detector equipment comprises a plurality of detectors shown in Figure 1. The detector comprises one or more measur- ing rods 21 , 31. The measuring rods constitute a measuring fork by which the shape of a bottle is measured. Also the type of the bottle can be determined on the basis of the bottle's shape. In addition to the bottle's shape, the measuring fork also measures the bottle's diameter. The diameter is measured at several different points in the vertical direction. On the basis of measuring the bottle, the bottle type can at least partially be determined.

The measuring rods 21 , 31 are secured to the frame of the detector from their first end. The second end of the measuring rod 21 , which is free, comprises a measuring head 22. The second end of the measuring rod 31 is also free. In addition, the measuring rod 31 comprises a measuring head 32 on the free end. The figure shows that the measuring heads are directed towards the side of the bottle 10.

The detector equipment further comprises a measuring means 50 consisting of means 51 and 52. Furthermore, the detector equipment comprises a data processing means 80 and a means 90. The measuring means 50 is operatively connected to the measuring rods. The measuring means 50 measures the horizontal movement of the measuring heads. In the solution according to Figure 1 , a means 51 comprised by the measuring means 50 is a distance sensor 51 , for example, and a means 52 is a counterpart to the distance sensor. The measuring means can further be implemented by a linear potentiometer or an angular sensor, for example.

Information has previously been stored in the data processing means 80 by means of which the bottles can be detected. The measuring means 50 and the data processing means 80 are interconnected, in which case measurement information obtained from the measuring means is con- veyed to the processing means to be processed. The processing means 80 compares the measurement information obtained from the measuring means with the previously stored information. The processing means 80 first processes the measurement information, and subsequently compares the processed measurement information with the limit values. Next, the processing means 80 makes a decision about the type of the bottle. In this step, determining the bottle type is only based on measuring the shape or diameter of the bottle. The processing means 80 can be implemented, for example, by a computer with software suitable for processing the measurement information.

The measuring rods 21 , 31 are, for example, fastened to the frame of the detector with bearings. In addition, hinges can be used for the fastening. The fastening allows the measuring heads to travel freely in the horizontal di- rection in the direction shown by arrow 41. The detector equipment further comprises a means 45, which in practice is implemented by a spring. The means 45 can also be implemented by a pneumatic cylinder. The means 45 draws the measuring rods to each other, in which case the measuring heads 22, 32 of the measuring rods follow the contours of the bottle 10. The attractive force of the means 45 is relatively small. The means 45 is arranged such that it does not draw the free ends of the measuring rods together even when the measuring rods' measuring heads do not measure the bottle. Hence, the measuring rods are immediately ready to measure the bottles when they are received to be detected.

The means 90 in the detector equipment is operatively connected to the frame of the detector equipment. The means 90 cam be implemented, for example, by an electric motor. The means 90 can also operate pneumatically. The means 90 moves the detector equipment in the vertical direction. The means 90 makes a movement to and fro at a pace determined by the bottles to detected. In practice, the detectors comprised by the detector equipment move simultaneously in the vertical direction shown by arrow 40. The detectors are arranged in the detector equipment in such an order that they are always ready to detect bottle groups received by the detector equipment. In practice, the detector receives bottle groups that are in a previously known order, in which case the detector order and the distance between the detectors of the same detector equipment can be fixed.

In practice, the detector equipment receives bottles of different volumes, shapes and colours. The detector equipment is capable of discerning bottles of different shape from each other, for example. The distance between the detectors in the detector equipment can be changed, which enables bottles from different crate types with varying distances between the bottles to be detected. The detector equipment can readily be changed such that the distance between the detectors corresponds to the distance between the bottles in a crate or on a bottle carrier.

The measuring rods are moved along the surface of the bottle to be detected in the vertical direction. The measuring rods 21 , 31 are secured to the detector equipment from the first end of the measuring rod such that the second end with a measuring head is enabled to travel along the outer surface of the bottle. At the detector equipment, the bottles can be detected by measuring the bottles' diameter and shape. Each single detector comprises a measuring fork with which an x-coordinate is generated to designate the diameter of the bottle to be detected. The diameter is measured when the means 90 low- ers the measuring rod along the bottle located in a crate. In practice, the measuring heads 22, 32 of the measuring rods 21 , 31 enter the crate. Furthermore, a y-coordinate shared by all detectors in one detector equipment is generated to indicate the detectors' height position at a given time.

Detecting bottles is based on measuring the bottle's diameter at different points of the bottle by means of the measuring fork and the measuring means 50. The detector equipment preferably comprises the same number of measuring forks as the detector equipment has bottles deposited in the crates. The detector equipment can also receive the bottles to be detected in some other way than deposited in a crate. For example, the bottles can be arranged in suitable bottle groups without being in a crate. The bottles of a bottle group preferably form a similar arrangement to that formed by bottles deposited in the crate. In practice, however, an arrangement described above requires a suitable carrier or a bottle holder in order for the bottles to be received by the detector equipment not to fall down. The equipment of the invention is particularly well suited for detecting plastic bottles, which are susceptible to fall, since the bottles to be detected can be conveyed to the detector equipment in a crate or other such bottle pallets.

Assume that the detector equipment 60 receives a crate comprising bottles to be detected. The crate stops under the detector equipment, after which the means 90 lowers the detector equipment, whereby each measuring rod's measuring head comes into contact with the surface of a bottle in the crate. The measuring means 50 can obtain the first measurement value almost immediately after the measuring fork has come into contact with the bot- tie. After the first contact, the distance between the measuring heads starts increasing for a time. The means 90 continue lowering the measuring equipment, whereby the measuring heads travel an increasingly long distance along the surface of the bottle being measured while the measuring means 50 take samples of the bottle's diameter. The measuring heads can also comprise ro- fating rolls, for example, in which case the sliding of the measuring heads on the surface of the bottle probably decreases. Consequently, measuring the bottle's shape is then mainly based on the measuring head rolling along the surface of the bottle.

When the measuring heads have travelled a predetermined distance along the surface of the bottle, the means 90 eventually start lifting the detector equipment upwards. It is also feasible to detect bottles when the means 90 lift the measuring heads upwards. Also in that case, the measuring heads and the measuring means 50 perform measurements that are based on measuring the bottle's shape or diameter.

The measuring means 50 transmit measurement information ob- tained from measuring each bottle to the means 80, which compares the measurement information with reference information. On the basis of the comparison, the means determine the bottle type. If the bottle measurement information does not correspond to any reference measure with a sufficient accuracy, the bottle can be detected on the basis of the slope of the bottle's profile. Information obtained from a change in the slope of the bottle's profile can be utilized in detecting the bottle. The bottle can be measured by using only one measuring head which is moved along the surface of the bottle. In the above- mentioned case, a special bottle depresser holds the bottle stationary and centralizes the bottle for the measurement. This enables the measuring head to be moved along the surface of the bottle in the horizontal direction. The measuring head can be moved in the horizontal direction around the bottle. Horizontal measurements can also be performed in the vertical direction at different points of the bottle. The above-mentioned method can also be employed in detecting asymmetrical bottles, for example. The measuring means 50 further detect with which detector fork the measurement information obtained is associated. In practice, each detector fork has its own measuring means. The information is also transmitted to the means 80, whereby the means 80 know the place of each detected bottle in the crate. When the measuring heads have travelled along the bottle's surface the predetermined distance, which can be 100 mm, for example, the means 90 lift up the detector equipment, whereby the measurement of the bottles in the crate ends. Measuring the bottle's shape can be based on upward movement of the measuring heads along the surface of the bottle towards its mouth. Measuring can also be based on downward movement of the measuring heads towards the bottom of the bottle. Figure 2 shows an embodiment of the detector equipment. In addition to the devices mentioned above, the detector equipment shown in Figure 2 comprises means 35 and 36. The means 35 presses down the bottle to be detected, whereby the bottle becomes stationary when the measuring heads travel towards the mouth of the bottle following the bottle's shape. The means

35 thus serves as the bottle depresser mentioned above. The means 35 holds the bottle stationary especially when the measuring heads travel upwards along the surface of the bottle. The means 35 generates the force necessary for pressing down the bottle by the means 36. In the solution in accordance with Figure 2, the means 36 is implemented by means of a spring. The means

36 can also be implemented as gravity-operated, for example. If the means 35 holds the bottle stationary, the bottle can only be measured, for example, by the measuring head 22 of the measuring rod 21.

Figure 3 shows a bottle sorting apparatus of the invention compris- ing bottle detector equipment 100, bottle sorting means 120, bottle passages 141 to 143 and means 130. The sorting apparatus of the figure further comprises a conveyor 201 , which conveys bottles arranged in crates or bottle groups uninterruptedly crate by crate to the detector equipment 100. The sorting apparatus further comprises means 110 located between the detector equipment 100 and the bottle sorting means 120 in the solution of Figure 3. The detector equipment 100 is, in the solution of Figure 3, connected to the means 110 by a conveyor 202, which forwards bottles in crates, for example.

When the detector equipment 100 has detected the bottles received on the basis of shape, the bottles in crates are conveyed to the means 110, which detect the colour of the bottle. In this manner, bottles that were detected to be similar on the basis of shape but which, however, differ in colour, are detected, in which case the bottles of different colour can be sorted later. The means 110 can also be located at the detector equipment 100, in which case the colour and shape of the bottle are simultaneously detected. The colour can also be detected before the bottle's shape. In practice, the means 110 are implemented by optical signal transceiver measuring a signal reflected from the bottle or propagated through the bottle.

After colour detection the bottles in crates are conveyed by a conveyor 203 to the bottle sorting means 120, which sorts the bottles on the basis of the information obtained from the detection. The detection means 120 grip the bottles on the conveyor and preferably lift up bottles of several crates or bottle groups simultaneously from the conveyor 203 and deposit each lifted bottle further in a bottle passage corresponding to each bottle type. The sorting means 120 deposit the bottles on the first end of the bottle passage. For each bottle passage there is a predetermined bottle type, which the bottle passage forwards towards the second end of the bottle passage. The bottle passages 141 to 143 are separated from each other by side guards, whereby the bottle types transferred in different bottle passages cannot be mixed up. Furthermore, the side guards prevent the bottles from falling off the bottle passage. The bottle passages can also be separated from each other by providing a suitable gap between the passages.

The sorting apparatus 120 comprises separate gripper arrays 121. Each gripper array consists of separate grippers. Each gripper array can separately convey bottles to different passages. Bottles are conveyed such that the same gripper array at a time lifts, for example, a group of bottles comprising bottles of different types from different crates or bottle carriers. Next, the gripper array deposits each lifted bottle in a bottle passage assigned thereto. In other words, bottles of a similar type are deposited in the same bottle passage. The mutual positions of the grippers of the gripper array 121 can be changed during the operating cycle, in which case the bottles to be transferred by the same gripper array at a time can be deposited in the different passages simultaneously.

Figure 4 shows the structure of a bottle passage. Between side guards, the bottle passage comprises intermediate guards 151 , 152 to arrange the bottles in lines. The intermediate guards enable using mechanical bottle grouping devices to be avoided. If one bottle line has much more bottles than the other lines, the means 130 lift more bottles from the bottle line of said passage. If necessary, the means 130 can lift fewer bottles from one passage's bottle line than from the bottle lines of another passage, whereby the number of bottles in the bottle lines remains in balance. Referring to Figure 3, assume that the sorting means 120 lift from the conveyor 203 a number of bottles corresponding, for example, to a number of bottles in three crates, 36 in total, for example. After having lifted the bottles, the sorting means 120 with the bottles move to the bottle passage 143, in which the sorting means only deposit bottles of the type corresponding to the bottle type predetermined for the bottle passage 143. In some cases, bottles that are not of a similar type can be deposited in the same bottle passage. Af- ter the sorting means 120 have deposited the bottles of the bottle passage 143 in the bottle passage 143, the sorting means 120 move to the bottle passage 142, in which the sorting means 120 only deposit bottles of the type corresponding to the type predetermined for the bottle passage 142. Next, the sorting means 120 move to the bottle passage 141 , in which the sorting means 120 only deposit bottles of the type corresponding to the bottle type predetermined for the bottle passage 141.

The sorting means 120 are capable of depositing bottle types corresponding to each bottle passage in each bottle passage. This is possible because the means 80 transmit to the sorting means 120 information on the location in the crate of each bottle received by the sorting means. In addition, the means 80 transmit information on the type of each bottle to the sorting means 120. The sorting apparatus has previously determined which bottle types to deposit in which bottle passage. It can also predetermine that several types of bottles are deposited in one bottle passage. Determination can be carried out by the means 80 which can also control other operation of the sorting apparatus. When the sorting means 120 have deposited all bottles in the bottle passages, the sorting means return to their initial position and lift from the conveyor 203 the next 36 bottles that are sorted in the bottle pas- sages in the manner described above.

In the bottle passage, bottles deposited therein move in the direction shown by arrow 150 towards the second end of the bottle passage. The means 130 lift the bottles from the second end of the bottle passage, after which the bottles are transferred to empty crates located on a conveyor 204.The same means 130 can lift bottles of several types. In practice, the means 130 lift from the bottle passages a number of bottles necessary for filling at least one crate. The means 130 transfer the lifted bottles to the crates, each crate being filled with bottles detected to be of the same type. The means 130 lift from the bottle passage 143, for example, a number of sorted bottles necessary for filling several crates and fill the empty crates with the bottles. Next, the means 130 move to the bottle passage 142, for example, and fill the crates with bottles of said bottle passage.

A plurality of means 130 can be in operation simultaneously, which enables empty crates to be filled quicker. The means 130 always retrieve bot- ties from a bottle passage with the most bottles and fill the crates with the retrieved bottles, whereby the bottle passage can be prevented from becoming full of sorted bottles. When the empty crates are filled with the sorted bottles, the crates full of bottles are forwarded by a conveyor 205. The figure shows that two other conveyors 206, 207 are provided parallel to the conveyor 205. Each conveyor can be arranged to convey bottles supplied from a predeter- mined bottle passage.

The means 130 comprise gripper arrays 131 , which transfer the bottles from the bottle passages to the crates or the bottle carriers as mentioned above. The same gripper array 131 can transfer bottles of different types from different passages to the crates or some other bottle carrier. The gripper array then deposits the bottle in a crate or on a carrier corresponding to the bottle type to be deposited. If it is assumed that the same gripper array has lifted bottles of types b and c, the gripper array conveys bottles of both types towards crates with empty places for the bottles at a time, and first deposits the type b bottles, for example, in their crate. After depositing the type b bottles in the crate, the gripper array deposits the type c bottles in their crate. In practice, the gripper arrays 121 and 131 can be the same gripper arrays, in which case the same gripper array can transfer the bottles both to and from the passages. The gripper arrays 121 , 131 can operate pneumatically, for example. The sorting apparatus can comprise a gripper array comprising 24 grippers, for example. Each single gripper can grip one bottle at a time. The gripper array preferably comprises as many grippers as the crates have bottles or bottle places. The grippers move sideways with respect to each other such that each gripper is able to put down the lifted bottles onto a conveyor, for ex- ample. The grippers deposit the bottles between the side guards in the passage. Each gripper can be controlled separately, for example pneumatically.

The shape detector equipment's detector group can move to and fro in the horizontal direction. When the bottles are being detected, the detector group travels at the same speed as the boxes moved on the conveyor. The shape detector group is synchronized with the box conveyor such that a suitable number of bottles is continually supplied to be detected. The shape detector equipment can simultaneously detect bottles in four crates, for example. The bottle passages' bottle conveyors are synchronized with the sorting means 120 emptying the crates by utilizing, for example, frequency transform- ers. As stated earlier, each bottle can be detected by measuring the bottle's diameter and shape by means of the detector equipment. The detector can measure the bottle's diameter at several different vertical positions, whereby a bottle diameter corresponding to each height position is found out. The height position value and a corresponding bottle diameter value can be placed on the x-y coordinates. When a sufficient number of the above- mentioned values that are placed on the coordinates have been measured from the bottle, the bottle type of the bottle can be determined. Since the measuring heads travel along the surface of the bottle, many measurement values can be obtained if necessary, in which case the bottle's profile can be determined at a desired vertical position zone. The profile enables the bottle type of the bottle to be determined. The fact that the height position of the detector is constantly known allows the height of the bottle to be measured, whereby the bottles can be detected on the basis of the height. When the bot- tie depresser approaches the mouth of the bottle, the measuring heads are in a "stand-by" position in the lower part of the bottle depresser. When the bottle depresser is further lowered, the bottle depresser eventually meets the mouth of the bottle. Next, the measuring heads move under the lower part of the bottle depresser, whereby the span of the measuring heads changes relatively fast. The fast change in the measuring head span can be detected, in which case it can be further utilized in determining the height value of the bottle.

While being detected, the bottles can thus be measured at several different vertical points as can be seen from Figure 2. In Figure 2, the bottle is measured at points A and B. The bottles can even be better detected in such a manner that first the bottle's diameter D is measured at least at two points A and B. Next, a difference DA-DB is calculated, whereby the bottle obtains a unique numerical value on the basis of which the bottle type of the bottle can be determined. In the above-mentioned manner, as many unique numerical values as necessary can be calculated for the bottle at a given time, whereby the bottle can be detected more efficiently. In addition, a change in the curvature of the bottle's surface can be measured from the bottle, in which case the bottle is detected on the base of the change in the curvature, for example.

After the detection, the sorting apparatus of the invention preferably simultaneously lifts a group of several bottles out of the box, boxes or other bottle carriers. Although the bottle group to be lifted out comprises bottles of several different bottle boxes, the bottle group to be lifted out only comprises some of the bottles of each crate. For example all bottles can be simultaneously lifted out of the crate. The bottles can be lifted in groups of several bottles, in which case a single group can comprise bottles of different types. Each bottle belonging to the same bottle group can be lifted up at one go, after which the bottles are conveyed to a bottle passage corresponding to each bottle.

The bottles do not necessarily have to be transferred from the bottle passages to the crates such that a number of bottles corresponding to the bottles in one or more crates is transferred to the crates or some other bottle car- rier at one go, but the transfer can be performed in several different steps.

In addition to a bottle depresser, the means 35 can also serve as a gripper to lift the bottles during the different steps of the sorting. The detector can also be placed at the gripper. When the means 35 serves as the gripper, it can grip bottles of different types since the measuring rods also move in the horizontal direction. The grippers constitute gripper arrays. The same gripper array can lift sorted bottles from the bottle passages and fill the crates or other such bottle pallets with the lifted bottles. The same gripper array successively fills the crates with the sorted bottles, which can also be of different types in such a manner that one crate or carrier only receives bottles of one type. Although the invention has been described above with reference to the example in accordance with the accompanying drawings, it is obvious that the invention is not restricted thereto but it can be modified in many ways within the scope of the inventive idea disclosed in the attached claims.

Claims

1. A method of sorting bottles, the method being used in a bottle sorting apparatus, characterized by detecting each bottle such that during the detection, each bottle is measured while deposited in a crate or belonging to a bottle group of a plurality of bottles by one or more measuring rods, each measuring rod having a measuring head (22, 23) of its own, which is moved along the surface of a bottle to be detected, transferring detected bottles of one or more crates or bottle groups to a bottle passage (141 to 143) specific to each bottle type, in such a manner that the bottles in the crates or bottle groups are lifted out of the crate or from their carrier and the lifted bottles are conveyed to the bottle passages (141 to

143), and depositing bottles detected to be of a similar type in each bottle passage.

2. A method as claimed in claim 1, characterized by lifting simultaneously from the same bottle passage (141 to 143) a number of sorted bottles corresponding to a number of bottles in one or more crates, and filling up one or more crates with sorted bottles of a similar type.

3. A method as claimed in claim 1, characterized by lifting from different bottle passages (141 to 143) a number of sorted bottles corresponding to a number of bottles in a plurality of crates, and filling the crates with said bottles such that bottles of a similar type are deposited in the same crate.

4. A method as claimed in claim 1, c h a r a c t e r i z e d by determining, before sorting the bottles, the colour of the bottles in the crates.

5. A method as claimed in claim 1, characterized by moving the measuring head (22, 32) of each measuring rod in the vertical direction when the bottle is measured, whereby the span of the measuring heads changes according to the bottle's shape and diameter, after which measurement values obtained by means of the measuring heads are compared with previously known reference values, and the bottle type is inferred on the basis of the measurement results obtained from measuring the bottle.

6. A method as claimed in claim 1, characterized by sliding each measuring head (22, 32) uninterruptedly along the surface of the bottle and measuring the horizontal distance between the measuring heads during the sliding.

7. A sorting apparatus, which is used for sorting bottles and which comprises a conveyor (201 ) to convey bottles to be sorted, characterized in that the sorting apparatus comprises detector equipment (100) comprising a plurality of detectors (60), and receiving from the conveyor (201) bottles (10) arranged in crates or bottle groups, and comprising, for each bottle to be detected, one or more measuring rods (21, 31), each measuring rod comprising a measuring head (22, 32) of its own, which measuring head travels along the surface of a received bottle measuring the bottle, sorting means (120) receiving the bottles detected by the detector equipment, the bottles being transferred, arranged in the crates or bottle groups, to the sorting means (120), a bottle passage (141 to 143) for each bottle type, whereto the sorting means (120) transfer the detected bottles in such a manner that the sorting means (120) lift the bottles of one or more crates or bottle groups re- ceived out of the crate or from their carrier, after which the sorting means (120) deposit bottles detected to be of a similar type among the lifted bottles in a bottle passage (141 to 143) corresponding to said bottle type.

8. A sorting apparatus as claimed in claim 7, characterized in that the sorting apparatus comprises means (130) for lifting simultaneously from the same bottle passage a number of sorted bottles corresponding to a number of bottles in one or more crates, and for filling up one or more crates with sorted bottles of a similar type.

9. A sorting apparatus as claimed in claim 7, characterized in that the sorting apparatus comprises means (130) for lifting from different bottle passages a number of sorted bottles corresponding to a number of bottles in a plurality of crates, and for filling up the crates with said bottles such that the means (130) deposit bottles detected to be of the same type in the same crate.

10. A sorting apparatus as claimed in claim 7, character- i zed in that the sorting apparatus comprises means (110) determining the colour of the bottles in the crates.

11. A sorting apparatus as claimed in claim 7, characterized in that the sorting apparatus comprises means (90) moving each measuring head (22, 32) in the vertical direction when the bottle is measured, whereby the span of the measuring heads changes according to the bottle's shape and diameter, and measuring means (50) measuring the measuring head span, and means (80) comparing measurement values obtained from the measuring means (50) with previously known bottle reference values.

12. A sorting apparatus as claimed in claim 7, characterized in that the sorting apparatus comprises measuring means (50) measuring the distance the measuring heads (22, 32) have travelled in the horizontal direction.

13. A sorting apparatus as claimed in claim 7, characterized in that the sorting apparatus (120) lifts at a time the bottles of one or more crates or bottle groups received out of the crate or from their carrier.

14. Detector equipment (100), which is used for detecting bottles, characterized in that the detector equipment comprises a plurality of detectors (60), each detector comprising one or more measuring rods (21, 31) for each bottle to be detected, each measuring rod comprising a measuring head (22, 32), and means (90) moving each measuring rod (21, 31) in such a manner such that the measuring head (22, 32) in the measuring rod travels along the outer surface of the bottle simultaneously measuring the bottle, each bottle being deposited in a crate or arranged in a bottle group during the detection.

15. Detector equipment as claimed in claim 14, character- i z e d in that when the detector equipment comprises at least two measuring rods, the means (90) move the measuring rods (21, 31) in the vertical direction when the bottle is measured, whereby the span of the measuring heads (22, 32) in the measuring rod changes according to the bottle's shape and diameter.

16. Detector equipment as claimed in claim 14, characterized in that the detector equipment comprises measuring means (50) for measuring the change of the span of the measuring heads in the measuring rods at several predetermined points while the measuring heads travel along the outer surface of the bottle, and means (80) comparing measurement val- ues obtained from the measuring means (50) with previously known reference values.

17. Detector equipment as claimed in claim 14, characterized in that the measuring heads (21, 31) are located substantially on the opposite sides of the bottle during the measurement.

18. Detector equipment as claimed in claim 14, character- i z e d in that the measuring heads (22, 32) move uninterruptedly along the surface of the bottle, and the detector equipment comprises measuring means (50) measuring, while the measuring heads move, the horizontal distance between the measuring heads with respect to a predetermined reference point.

19. Detector equipment as claimed in claim 14, characterized in that the measuring heads move up and/or down along the surface of the bottle when the bottle is measured.

20. Detector equipment as claimed in claim 14, characterized in that the measuring rod (21 , 31 ) is secured to the detector equipment from the first end of the measuring rod such that the second end with a measuring head is enabled to travel along the outer surface of the bottle.

21. Detector equipment as claimed in claim 14, characterized in that the measuring heads (22, 23) move along the surface of the bottle sliding or rolling.

22. Detector equipment as claimed in claim 14, characterized in that the detector equipment comprises means (80) whereto information is transmitted on the height position of the detector (60) at the time of the measurement.

23. Detector equipment as claimed in claim 14, character- i z e d in that the measuring heads (22, 23) measure the shape of the bottle such that the measuring heads measure the diameter of the bottle at different heights.

24. A detection method, which is used for detecting bottles, characterized by moving along the outer surface of a bottle to be detected, the bottle being deposited in a crate or arranged in a bottle group during the detection, at least one measuring rod's (21, 31) measuring head (22, 32) measuring the bottle's profile while moving along the surface of the bottle, and comparing measurement values obtained from measuring the bot- tie's profile with previously known reference values, after which the type of the bottle to be measured is determined.

25. A detection method as claimed in claim 24, characterized by moving the measurement rods (21, 31) in the vertical direction when the bottle is measured, whereby the span of the measuring heads (22, 32) in the measuring rod changes according to the bottle's shape and diameter.

26. A detection method as claimed in claim 24, characterized by measuring the change in the measuring head span at several predetermined points when the measuring heads travel along the outer surface of the bottle.

27. A detection method as claimed in claim 24, character- i z e d by keeping the measuring heads (21 , 31 ) substantially on the opposite sides of the bottle during the measurement.

28. A detection method as claimed in claim 24, characterized by moving the measuring heads (22, 32) uninterruptedly along the surface of the bottle, and measuring the horizontal distance between the measuring heads with respect to a predetermined reference point while the measuring heads move.

29. A detection method as claimed in claim 24, characterized by moving the measuring head up and/or down along the surface of the bottle when the bottle is measured.

30. A detection method as claimed in claim 24, characterized by sliding or rolling the measuring head (22, 23) along the surface of the bottle.

31. A detection method as claimed in claim 24, characterized by measuring the height position of the measuring head (22, 23) with respect to the bottle during the measurement of the bottle's profile.

32. A detection method as claimed in claim 24, characterized by measuring the bottle's diameter at different heights in measuring the shape of the bottle.