US3517641A - Article detecting device - Google Patents

Description

June 30, 1970 G. B. BOYCE ARTICLE DETECTING DEVICE Filed July 9, 1968 'IINVE TOR ATTORNEY 3,517,641 ARTICLE DETECTING DEVICE Guy Baron Boyce, Blagdon, England, assignor to Binks- Bullows Limited, Brownhills, England Filed July 9, 1968, Ser. No. 743,461 Claims priority, application Great Britain, July 13, 1967, 32,298/ 67 Int. Cl. B05c 11/00 US. Cl. 118-2 4 Claims ABSTRACT OF THE DISCLOSURE A device for detecting the presence of an article on which it is desired to carry out an operation by means of a further device or machine, comprising a pivotally mounted vane and at least one nozzle arranged to be connected to a supply of pressurised fluid, the article being arranged to pass between the nozzle and the vane so that the absence of an article between the nozzle and the vane will result in a stream of pressurised fluid impinging on the vane to move it to a first position, whereas the pressure of an article between the nozzle and the vane will interrupt the stream of pressurised fluid to enable the vane to move to a second position in which the vane or a part movable therewith actuates means for initiating operation of said further machine or device.

This invention relates to an article detecting device. Such a device may be used for example where it is required to carry out an operation of some kind on a series of articles which are advanced in succession to a station where the operation is to be carried out. The operation itself may be performed automatically but obviously it is desirable to ensure that an article is actually positioned in the operating station before the machine or other means carrying out the operation is actuated. Devices for detecting the presence or absence of an article are known but many of these devices are electrically actuated and suffer from disadvantages such as fire hazard or (particularly when the devices are operating in wet conditions) the possibility of malfunctioning.

The object of the present invention is to provide an article detecting device which is simple and inexpensive to construct and yet reliable and eflicient in operation.

An article detecting device in accordance with the invention comprises a pivotally mounted vane, at least one nozzle adapted to be connected to a supply of pressurised fluid whereby in use at least one stream of such fluid can be directed towards said vane, the vane and the nozzle being arranged so that articles to be detected will pass between the vane and the nozzle, the vane being pivotable between a first position to which it is deflected by the stream of pressurised fluid impinging on it in the absence of an article between the vane and the nozzle and a second position which it assumes when said stream of pressurised fluid is interrupted by the presence of an article between the vane and the nozzle, there being provided means actuable by the vane when the latter is in said second position for initiating operation of a further machine or device at a pre-determined interval after the vane has moved into its second position.

Conveniently, said means actuable by the vane includes a rotatable table which carries at spaced intervals around its periphery a plurality of actuator elements which are each mounted so as to be pivotable relative to the table about an axis which is parallel to the axis of rotation of the table. The table would be rotated in use at a speed which corresponds to the speed of advance of articles (e.g. on a conveyor) towards the detecting device and said vane or a part movable therewith would be arranged to United States Patent Office Patented June 30, 1970 actuate a movable arm which is itself adapted to engage an actuator element when the vane is in its second position to move said element to an operative position in which it will actuate the further machine or device when the table has rotated to a pre-determined position.

The invention will now be more particularly described with reference to the accompanying drawing which is a schematic perspective view showing one example of an article detecting device in accordance with the invention.

In the example shown in the drawing there is provided a vane 10 which is mounted at or adjacent to the lower end of a rod or arm 11 which is pivotally mounted at its upper end on a support 12 so as to be pivotable about a horizontal or generally horizontal axis. The vane is conveniently of part-cylindrical configuration with the axis of curvature extending in a vertical direction and facing the concave side of the vane is one end of a tube 13, the other end of said tube being aligned with at least one nozzle 14 which is adapted to be connected in use to a supply of pressurised fluid such as compressed air. Thus in use and in the absence of any obstruction between the tube 13 and the nozzle 14 a stream of compressed air issuing from the nozzle will pass along the tube and impinge on the vane and will deflect it to a first position. On the other hand if an obstruction in the form of an article 15 which is to be detected moves between the nozzle 14 and the tube 13 the stream of compressed air will no longer impinge on the vane 10 and the latter will then fall under the influence of gravity and the bias of a weight 16 to a second position (as shown in the drawing) which is angularly spaced from the aforementioned first position. Alternatively, the tube 13 can be dispensed with and the stream of air issuing from the nozzle will, in the absence of an article between the nozzle and the vane, impinge directly on the vane. As above described one nozzle is used but two nozzles may be used so that both air jets have to be interrupted before the vane can assume its second position. This arrangement is required when an empty work holder itself interrupts the air jet from a single nozzle-the use of two nozzles requiring that both air jets must be interrupted (by an article) before the vane will move to its second position.

There is also provided a table 17 which is rotatable about a vertical axis and which carries at spaced intervals around its periphery a plurality of actuator elements 18 (three of said elements being shown) which are each mounted so as to be pivotable relative to the table about an axis 18a which is parallel to the axis of rotation of the table. The actuator elements can alternatively be carried by a belt or chain but in this instance each element conveniently extends through the table and on one side of the table there is provided a bar 19 which projects from opposite sides of a short spindle 20 which forms part of the actuator element and on which the element pivots. The inner end of each bar can move between a pair of short pegs 21 which act as stops to limit the angular movement of said spindle whilst the outer end of the bar 19 projects outwardly beyond the periphery of the table so as to be engageable by an arm 22. Said arm is resiliently mounted or (as shown) is itself resilient so as to be biased towards an inoperative position (indicated in dotted lines by reference numeral 22a) in which it will not engage the outer end of the bar 19 of an actuator element as the table 17 rotates; 0n the other hand, when an article 15 is present between the nozzle and the vane, the latter will move to its second position. In this second position either the vane or (as shown) a part, namely the rod 11, movable with the vane engages the arm 22 to move the latter to its operative position in which it will engage the outer end of the bar 19 of the next actuator element which is presented to the arm 22 as the table 17 rotates. This actuator element (which is provided like all the other actuator elements with a roller 23) will then be turned so that said roller is adapted to engage a switch, valve or other means indicated generally by reference numeral 24 disposed at a pre-determined position (which may be adjustable) relative to the table 17, said means 24 being arranged to actuate a further machine or device (not shown). In addition any suitable form of projection 25 or other means is used to restore the bars 19 of the actuator elements to their original or inoperative positions after they have passed said switch, valve or other means 24.

In one application of the above-described article detecting device the articles 15 would be delivered in succession by a conveyor 26. The rotatable table 17 would also be driven (by any conventional means) at a speed corresponding to the speed of advance of said conveyor. Thus the table and the conveyor may be mechanically interconnected as shown in the drawing by a driving shaft 27. The aforementioned further machine or device may comprise an automatically actuated paint spraying apparatus (not shown) of conventional form which will emit a spray of paint at the appropriate moment when the article is aligned with the apparatus, the apparatus being actuated as above-described by the means 24. Thus the paint spraying apparatus will be disposed ahead of the nozzle 14 by a distance such that the conveyor will traverse said distance in a time which corresponds to the time taken by an actuator element to pass between the arm 22 and the means 24.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a conveyor system, an article detecting device for detecting the presence or absence of articles travelling along the conveyor, said device comprising a pivotally mounted vane, at least one nozzle adapted to be connected to a supply of pressurised fluid whereby in use at least one stream of such fluid can be directed towards said vane, the member and the nozzle being arranged so that articles to be detected will pass between the member and the nozzle, the vane being movable between a first position to which it is deflected by the stream of pressurised fluid impinging on it in the absence of an article between the vane and the nozzle and a second position which it assumes when said stream of pressurised fluid is interrupted by the presence of an article between the vane and the nozzle, there being provided a support drivingly connected to said conveyor so as to be rotatable thereby, and a plurality of actuator elements carried by said support so as to be movable in a closed path and in a spaced relationship at a speed having a predetermined relationship to the speed of the conveyor, each actuator element being individually movable between an operative position and an inoperative position, movement into said operative position being effected at a first station in said closed path by said pivoted vane when the latter is in its second position, there being also provided means engageable by an actuator element when in its operative position and when at a second station in said closed path remote from the first station for carrying out an operation on an article advanced along the conveyor and previously detected by the article detecting device.

2. An article detecting device as claimed in claim 1 wherein there is provided an arm which is movable, by movement of the vane to its second position, into engagement with an actuator element so as to displace the latter into its operative position, said movable arm being resilient or resiliently mounted so as to be biased towards an imperative position in which it is not adapted to engage an actuator element.

3. An article detecting device as claimed in claim 1 wherein means are provided for re-setting to its inoperative position each actuator element which has been moved to an operative position after it has engaged said means for carrying out an operation on an article advanced along said conveyor.

4. An article detecting device as claimed in claim 1 wherein there is provided a tube which is disposed between said nozzle and said vane, one end of said tube being arranged to receive a stream of pressurised fluid from the nozzle when an article is not present between the nozzle and said end of the tube and the other end of the tube being arranged to direct such a stream of pressurised fluid onto the vane.

References Cited UNITED STATES PATENTS 1,966,093 7/1934 Grifiin 118-2 2,376,980 5/ 1945 Petersen et al 1182 2,499,621 3/ 1950 Archer 118-2 2,675,778 4/ 1954 Peeps 1l82 3,065,730 11/ 1962 Lyons 1l8- 8 3,146,126 8/1964 Baker 118-2 OTHER REFERENCES Product Engineering, Sept. 5, 1960, pp. 46, 47.

MORRIS KAPLAN, Primary Examiner

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