Size control

#This invention relates to size control. In particular, the application is applicable to checking the sizes of glass bottles being conveyed from a glass bottle manufacturing machine, but it will be appreciated that the invention is of generally wider applicability.

#For simplicity, reference will only be made in the following description to the manufacture of glass bottles but it is to be understood that the application relates generally to analogous processes in other fields.

#In the manufacture of glass bottles it is important to ensure that the bottles produced are all of the right size. It is particularly important to ensure that no bottle is produced which is over the maximum tolerance size since such a bottle could easily become stuck in subsequent handling machinery, e.g. bottle filling, cleaning or sealing machinery, with extremely disadvantageous results. It is naturally also desirable to eliminate bottles from production which are of less than the minimum size which can be tolerated, though the presence in automatic machinery of slightly undersized bottles does not generally cause very great problems.

#The invention is illustrated by way of example, with reference to a glass bottle checking machine which is diagrammatically shown in the accompanying drawings. In the drawings:

#FIG. 1 is a transverse section through the apparatus in use,

#FIG. 2 is a side view of the part of the apparatus to the left as seen in FIG. 1,

#Referring first to FIG. 1, this shows a bottle conveyor 200 on which is located a line of bottles 201. The conveyor runs between two units, mounted by means of mounting brackets 1, 2, 6, 7 on the framework of the conveyor (not shown). The left hand side unit (as seen in FIG. 1) comprises a fixed position free-running roller 48 mounted adjustably on a bracket 3. The right hand unit as seen in FIG. 1 comprises a free-running roller 48 mounted adjustably on a swinging plate 203. As also seen in FIG. 1, both rollers 48 are elongated (see also FIG. 5) and they engage the opposite sidewalls of the bottles 201 over substantially their entire height.

#The details of the roller mounting are shown in FIG. 5. The distance of the roller 48 from the plate 203 can be varied by screwing nuts 82, 51 along threaded support bars 44, and its inclination varied by the same method, movement being taken up in swivel joints 69, 46, 70. Attached to those joints is a face-plate 45 to which is secured an assembly of roller 48 and bracket 47. This assembly may be changed to match the apparatus to different bottle shapes or sizes by unbolting the assembly at 81. The roller 48 is made of polytetrafluoroethylene and has tapered ends to reduce the bearing surface on the bracket and so make the roller as free-running as possible.

#As can be seen most clearly from the plan view in FIG. 4, plate 203 is supported on a bracket 34 via a leaf spring 114. Spring 114 is clamped to bracket 34 and to plate 203 by means of clamping plates 35 and bolts 75. Bracket 34 can pivot about a post 36 and is bolted to the frame of the apparatus and tightened into position by bolt 76. This bracket is used to adjust the rest position and bias on plate 203 in conjunction with a stop 39 which is likewise bolted down on to the frame of the apparatus. Stop 39 just catches on the base of plate 203 and is first adjusted so that, when plate 203 is touching stop 39, the separation between the two rollers 48 is just smaller than the size of the articles to be checked. This ensures that only a small amount of movement of plate 203 takes place during use. Then bracket 34 is turned so as to press plate 203 lightly against stop 39, after which bolt 76 is tightened.