US3586578A

US3586578A - Sensing and control mechanism for label dispenser

Info

Publication number: US3586578A
Application number: US805575A
Authority: US
Inventors: Arthur C Dickerson
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1969-03-10
Filing date: 1969-03-10
Publication date: 1971-06-22
Anticipated expiration: 1988-06-22
Also published as: FR2037806A5; GB1299665A; DE7009137U

Abstract

A SENSING APPARATUS ADAPTED FOR USE IN CONTROLLING THE MOVEMENT OR DETERMINING THE POSITION OF A CARRIER WEB TO WHICH IS ATTACHED SPACED ARTICLES. THE SENSING DEVICE IS A ROTATABLE MEMBER ENGAGEABLE WITH SUCCESSIVE LEADING EDGES OF THE ARTICLES CAUSING ROTATION OF THE SAME AND ACTUATION, THROUGH A CAM ROTATED IN RESPONSE TO ROTATION OF THE SENSING DEVICE, AND MEANS FOR CONTROLLING THE MOVEMENT OR POSITION OF THE ARTICLES.

Description

June 22, 1971 DICKERSQN 3,586,578

SENSING AND CONTROL MECHANISM FOR LABEL DISPENSER Filed March 10, 1969 a X I 25 c l- //9 1 I Il I i 5. qiginlh. 30 34 33 n 2 |/Z7 I 23 Z2 I INVEN'IUR. 7 ,50 7 ARTHUR C. D/CKEPSON 'l I, I J l I MMfiflifiM 6 F1023 ATTORNEYS United States Patent 01 hce 3,586,578 Patented June 22., 1971 3,586,578 SENSING AND CONTROL MECHANISM FOR LABEL DISPENSER Arthur C. Dickerson, St. Paul, Minn., assignor to Minnesota Mining & Manufacturing Company, St. Paul,

Minn.

Filed Mar. 10, 1969, Ser. No. 805,575 Int. Cl. B65h 25/04; B3211 31/18 US. Cl. 156361 3 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to an improvement in a sensing device and in one aspect to an improved and simplified device for sensing the position of advancing labels adhered to a flexible backing or carrier relative to the separating edge of a dispenser.

It is necessary in the application of pressure-sensitive adhesive labels carried by a low-adhesion carrier web onto packages that the position of the labels on the web with respect to a separating edge be precisely controlled. If the position of the labels as they move toward the separating edge is not regulated, placement of the labels will not be made to the articles in an orderly fashion. Many attempts at the construction of a suitable sensing mechanism have been made and some elaborate and some rather sophisticated and sensitive devices have resulted. In each instance, the more movable pieces, the more parts there are to Wear and to need replacement, and the more sensitive the devices are the more apt they are to malfunction. Thus, simplicity is a necessary element of a succesful labelsensing apparatus.

Some examples of the prior art label-sensing devices are shown in US. Pats. No. 2,987,591; 3,039,516; 3,240,- 652; and 3,405,021.

The label sensing apparatus of the present invention provides a very simple and accurate mechanism for sensing the position of spaced articles movable therepast on a flexible web.

The present invention provides a label sensing apparatus which'is adaptable for use with various sized labels transported by a flexible low-adhesion carrier web to an applicating station of a label dispensing apparatus.

The present invention provides a label sensing device which is characterized by simplicity and accuracy.

The sensing device of the present invention comprises a rotatable star wheel, a cam driven by the star wheel, a spring to control the incremental movement of the star Wheel, and means responsive to the incremental movement of the star wheel for carrying out a control function such as the movement, position, separation etc. of the articles. The device is positioned in an area along the path of a carrier web where the surface opposite the device is unsupported.

The present invention will be more fully understood and its advantages appreciated after reading the following detailed description which refers to the accompanying drawing, wherein:

FIG. 1 is a side elevational view of a support arm of a dispenser having a sensing device constructed in accordance with the present invention;

FIG. 2 is a fragmentary plan view, partly in section of the dispenser illustrated in FIG. 1;

FIG. 3 is another elevational view of the dispenser of FIG. 1 showing the sensing device in another operative position; and

FIG. 4 is an elevational view of a modified dispenser having a sensing device constructed in accordance with the present invention.

Referring now to FIGS. 1 through 3, there is shown a flexible carrier strip or web 6 having positioned thereon a series of articles in spaced relation, which articles are, in the illustrated embodiment, pressure-sensitive adhesive labels 7 adhesively secured to a low-adhesion surface of said flexible web 6, forming a label tape. The flexible web 6 and labels 7 are advanced from a supply (not shown) by a guide roller 9 toward the surface of a label guiding plate 10 having at one end a transversely extending sharp separator edge 11 around which the flexible carrier strip 6 is drawn. The carrier Web 6 is drawn around the edge 11 by means of two cooperating

rollers

14 and 15, one of which is driven by a motor (not shown) and the other of which is urged into engagement with the flexible web 6, pressing the same into firm frictional contacting driving engagement with the driven roller. Actuation of the motor affords movement of the flexible carrier web 6. Above the surface of the plate 10 is disposed a bridge-like member 18 extending transversely of the plate and adjustably supported from an angle bracket 19. The angle bracket 19 may be carried by the plate 10, which plate could take the form of a swingable arm, or carried by a fixed support arm on the applicator or a pedestal positioned at the labelling station. The mounting for the bracket can be adjustable permitting its use with various thickness of the labels. A guide member 20 formed of light flexible sheet material is also secured to the angle bracket 19 to guide the label tape over the bridge 18 and back toward the surface of the plate 10 in advance of the separator edge 11. The guide plate 20 is bifurcated toward its unsupported end affording placement of a label sensing device constructed in accordance with the present invention in the path of the label tape,

The label-sensing device of the present invention comprises a relatively narrow axially supported hub 22 having outwardly extending tangential teeth 23 defining a star wheel. The star wheel is mounted for rotation by a shaft 24. The shaft 24 is cantilever mounted from a bracket 25 and the star wheel is bearinged on the shaft. Secured for rotation with the star wheel is a cam 27 having generally planar surface portions 28 joined by lobes 29, with a lobe to correspond with each tooth 23 on the hub 22. A leaf spring 30 supported from the bracket 25 has a free end positioned in contact with the cam 27 tending to alternately restrict rotation of the star wheel and to urge rotation of the star wheel to atford control of the star wheel and permit its rotation only upon positive contact of a tooth 23 thereof with the leading edge of the label 7 and to assure the position of a tooth 23 for contact with the leading edge of a subsequent label 7 upon each increment of rotation of the star wheel.

A switch 32 functions in response to the rotation of the star wheel and cam, from the position shown in FIG. 1 to the position of FIG. 3 and back to the position of FIG. 1, to carry out a control function. The switch 32 is supported in a position above the star wheel and has a cam following lever arm 33 disposed with a free end in contact with the cam 27 such that upon the rotation of the star wheel and contact of the free end of the arm 33 with a lobe 29 on the cam (see FIG. 3), a plunger 34 of the switch 32 is actuated to open or close the contacts of the switch for initiating a control function, e.g. the operation of the motor driving the flexible web.

The bridge 18 and its position above the planar label tape guiding surface of the plate 10 defines an area along the path of the label tape, where it is unsupported. This area allows the web to be flexed and allows the star wheel to rotate incrementally about the axis of its shaft 24 against the bias of the spring 30 to operate the switch 32. The angle bir 1-9, the bridge 18, and the label-sensing device as illustrated permit its location anywhere along the plate 10, affording the desired control for the web, with various sized labels.

Referring now to FIG. 4 there is illustrated an alternative form for the dispenser in the sensing device. In this embodiment the sensing device comprises a star wheel 35 and cam 36 but the plate 37, corresponding generally to plate 10, is provided with a recess 39 in the surface thereof adjacent to the separating edge 38 and beneath the tape guide 40. This recess 39 provides an unsupported area on the side of the label tape opposite the sensing device permitting rotational movement of the star wheel 35 much the same as the bridge 18.

The flexing of the web, i.e., the depression of the flexible web out of its normal path into the recess 39 or below the bridge 18, affords positive driving action for the star wheel to a greater extent than afforded by the mere engagement of a tooth thereon with a label moving along a linear path without deflection.

The present invention affords a sensing device which is positive and accurate for the rapid control of the tape. It is a simplified device compared to the prior known devices and adaptable to existing equipment.

Having thus defined the present invention, What is claimed is:

1. A sensing apparatus for use with a flexible tape having articles aflixed to one surface thereof in spaced relation, said apparatus comprising a guide defining a path of movement for the flexible tape and defining an area along said path where the tape is unsupported adjacent the surface opposite the articles, a wheel mounted for rotation about its axis and having teeth extending outwardly from said wheel and into said path along which the flexible tape is guided, means for mounting said wheel for rotation about an axis fixed relative to said guide and opposite said area, cam means connected for rotation with said wheel, resilient means for restricting rotation of said Wheel except upon contact of a tooth on said wheel with an article on a said tape moving along said path, and means responsive to the incremental rotation of said wheel and cam for carrying out a control function.

2. A label-applying apparatus comprising guide means defining a path for a flexible label-carrying tape leading to a transverse separating edge, said guide means defining at least one area in advance of the separator edge where the label-carrying tape is unsupported, means for advancing the label-carrying tape along said path over said one area and about said edge to separate the labels from the carrying tape, a star wheel positioned on the side of said path opposite said one area of the tape path and having circumferentially spaced teeth engageable with a labelcarrying tape and engageable with the lead edge of the labels thereon to rotate the star wheel, means for supporting said star wheel for rotation about an axis in fixed spaced relationship to said guide whereby rotation of said star wheel will cause deflection of the tape at said unsupported area, a cam connected to said star wheel and rotatable therewith, spring means engageable with said cam for restricting its rotation and for positioning said star wheel upon rotation thereof, and means responsive to the incremental rotation of said star wheel affording a control function.

3. A label-applying apparatus according to claim 2 wherein said means affording a control function comprises a switch having a plunger, a lever arm engageable with said cam and operated thereby to move and plunger.

References Cited UNITED STATES PATENTS 3,039,516 6/1962 Vinal l56-361 3,169,895 2/1965 Sohn l56-361 3,240,652 3/1966 La Mers 156-36l 3,405,021 10/1968 Marano 156-361 3,447,992 6/1969 Allen et al 156-361 SAMUEL W. ENGLE, Primary Examiner D. A. BENT, Assistant Examiner US. Cl. X.R. 156-541