WO2001036863A1

WO2001036863A1 - Chemiluminescent light apparatus and method of manufacture

Info

Publication number: WO2001036863A1
Application number: PCT/US2000/040692
Authority: WO
Inventors: Raymond J. Cramer; Carlos G. Saenz; Daniel Morales
Original assignee: Medi-Flex Technologies, Inc.
Priority date: 1999-11-17
Filing date: 2000-08-21
Publication date: 2001-05-25
Also published as: AU7883400A

Abstract

A chemiluminescent light apparatus is provided which includes a two-piece casing (10) that encloses a chemiluminescent composition (12). The casing includes a light-transmissive body (14) defining an interior cavity and including an end wall presenting an opening that communicates with the cavity, and a cap (16) received in the opening. The opening is stepped to define a shelf (28) that is generally parallel to and spaced from the end wall of the body, and the cap (16) includes a stepped region presenting a shoulder (36) that is sealed against the shelf of the opening to close off the interior cavity of the body. A first fluid component (18) of the chemiluminescent composition is enclosed in the interior cavity of the body, as is a hollow frangible ampule (22) within which a second component (20) of the composition (12) is encapsulated. When the ampule (22) is fractured, the first and second fluid components (18, 20) mix together and luminesce. A method of manufacturing a chemiluminescent light apparatus is also provided, wherein a light-transmissive body is positioned on a rotatable turntable (40) that is indexed from station to station to permit the various components of the apparatus to be assembled. At one of the stations, a cap is secured to the body by ultrasonic welding. .

Description

CHEMILUMINESCENT LIGHT APPARATUS AND METHOD OF MANUFACTURE

BACKGROUND OF THE INVENTION

The present invention relates generally to chemiluminescent lights, and more particularly to a multiple-piece chemiluminescent light apparatus and a method of its manufacture.

It is known to provide a chemiluminescent light stick capable of providing guidance or identification in emergency or low light situations. The light stick typically includes a flexible body formed of a suitable light-transmissive synthetic resin material, a frangible glass ampule supported within the body, and two fluids, one of which is an oxalate that is sealed within the ampule, and the other of which is an activator that is sealed within the body externally of the ampule. As such, the two fluids are kept isolated from one another prior to use, and mix when the ampule is fractured to chemiluminesce.

In the manufacture of a conventional light stick, it is known to employ a two-piece assembly including a hollow body presenting a closed end and an opposed open end, and a cap sized for receipt in the open end for closing off the interior cavity of the body and preventing the fluids in the cavity from leaking. Typically, the cap is secured to the body and sealed in place by spin-welding the mating circumferential surfaces of the two parts together. This is accomplished by spinning the cap and body relative to one another with the cap positioned in the open end of the body, generating heat that melts the material of the cap and body, welding the parts together. However, problems exist in the use of this type of apparatus and in its method of manufacture.

For example, in the manufacture of known light sticks, the one fluid is dispensed into the open end of the body prior to fitting of the cap, presenting an opportunity for some of the fluid to drip or splash onto the end of the body, wetting the area to be welded. As a result of this wetting action, friction between the body and cap is reduced and insufficient heat is generated during spin welding to completely seal the cap to the body. In these cases, an unacceptable product is manufactured that leaks.

Further, even if the conventional light stick is sealed at the time of manufacture, it is possible for leaks to develop when the body is flexed to fracture the ampule at the time of use. Such flexing is typically carried out about an axis transverse to the longitudinal axis of the body, creating stresses that can break the seal between the body and the cap. Because the seal between the components is between the inner circumferential surface of the body and the outer circumferential surface of the cap, flexure of the body during use can cause the two components to separate from one another along seams or lines that are parallel to the longitudinal axis of the body. As a result, leakage of the fluids results.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to solve the technical problems left unaddressed by the prior art, and to provide a chemiluminescent light apparatus having an improved seal between a body and cap thereof, and a method of manufacturing such an apparatus.

In accordance with these and other objects evident from the following description of a preferred embodiment of the invention, a chemiluminescent light apparatus is provided which includes a light-transmissive body defining an interior cavity and including an end wall presenting an opening that communicates with the cavity, and a cap received in the opening. The opening is stepped to define a shelf that is disposed in a plane generally transverse to the longitudinal axis of the body, and the cap includes a stepped region presenting a shoulder that is sealed against the shelf to close off the interior cavity of the body. The apparatus also includes a first fluid component enclosed in the interior cavity of the body, and a hollow frangible ampule enclosed in the interior cavity of the body, wherein the ampule encapsulates a second fluid component. When the ampule is fractured, the first and second fluid components mix together and luminesce.

A method of manufacturing a chemiluminescent light apparatus in accordance with the present invention includes, among other steps, the step of positioning a light-transmissive body on a rotatable turntable that is indexed from station to station to permit the various components of the apparatus to be assembled. At one station, a hollow frangible ampule is dispensed into the interior cavity of the body, wherein the ampule encapsulates a first fluid component of a chemiluminescent composition. At another station, a second fluid component of the chemiluminescent composition is dispensed directly into the interior cavity of the body. Subsequent to these steps, which can be carried out in any order, a cap is positioned in the opening of the body and welded to the body by ultrasonic welding. The body includes a shelf within the opening, and the cap includes an intermediate stepped region presenting a shoulder that seals against the shelf during welding. The turntable is then indexed to an unloading station where the completed apparatus is unloaded.

By providing a construction in accordance with the present invention, numerous advantages are realized. For example, by providing the cap of the apparatus with a step presenting a shoulder that engages a shelf of the body, it is possible to completely seal the body shut during manufacture by ultrasonically welding the cap and body together in the area of engagement between the shoulder and the shelf. In addition, because the seal between the components extends in a plane generally transverse to the longitudinal axis of the body rather than along the inner circumferential surface thereof, it holds up better to flexure of the body than does the seal in a conventional construction.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING The preferred embodiment of the present invention is described in detail below with reference to the attached drawing, wherein:

Fig. 1 is a perspective view of a chemiluminescent light apparatus constructed in accordance with the preferred embodiment, partially broken away to illustrate various elements forming a part thereof; Fig. 2 is an exploded fragmentary view of a body and cap forming a part of the apparatus;

Fig. 3 is a fragmentary view of the body taken along line 3-3 of Fig. 2; Fig. 4 is a sectional view taken along line 4-4 of Fig. 2; Fig. 5 is a fragmentary side elevational view of a roughened surface forming a part of the cap of the apparatus;

Fig. 6 is a fragmentary sectional view taken along line 6-6 of Fig. 1; and Fig. 7 is a schematic view of a machine for manufacturing a chemiluminescent light apparatus in accordance with the preferred embodiment. DETAILED DESCRIPTION OF THE INVENTION

A chemiluminescent light apparatus constructed in accordance with the preferred embodiment is illustrated in Fig. 1, and broadly includes a two-piece casing 10 within which a chemiluminescent composition 12 is enclosed. The casing includes an elongated body 14 and a cap 16, and the composition includes two separate components 18, 20, each of which is isolated from the other until the time of use. An ampule 22 is received in the body, and encapsulates one of the composition components 20 prior to use such that when the ampule is fractured, the two components 18, 20 mix and luminesce. The body 14 of the casing is generally tubular, including a first closed end, an opposed open end, and an interior cavity communicating with the open end and extending generally along the central longitudinal axis of the body. The body 14 is formed of a light-transmissive material, preferably a transparent or semi-transparent synthetic resin material such as low-density polyethylene (LDPE). The material employed possesses sufficient flexure to permit the body to be bent about an axis generally transverse to the longitudinal axis thereof, allowing the ampule to be fractured so that the components of the chemiluminescent composition will mix together and luminesce.

The closed end of the body can include structure 24 for attaching the apparatus to a person, vehicle, support device or the like to facilitate use of the apparatus in the desired environment of use. For example, in the illustrated embodiment, a button hook is formed in the closed end of the body for permitting the apparatus to be hooked to a person in order to provide light for the person in carrying out various tasks, or to make the person more easily visible to others. However, any other type of attachment or support structure can be provided for adapting the apparatus for an intended use. As shown in Fig.2, the body 14 includes a stepped end region 26 adjacent the open end thereof, and the end region includes a circumferential wall that is of a greater thickness than the circumferential wall along the remainder of the body. In addition, the inner surface of the end region that defines the opening in the body is stepped, presenting a shelf 28 that is disposed in a plane generally transverse to the longitudinal axis of the body. As illustrated in Fig. 3, an annular ridge 30 is formed on the shelf and defines an energy concentration zone on the shelf that facilitates securement of the body to the cap, as described below.

Returning to Fig. 2, the cap 16 is preferably formed of the same material as the body, and includes a first end 32 sized for receipt in the end region 26 of the body, an opposed axial end presenting a flange 34 that substantially covers the end of the body, and an intermediate stepped region presenting a shoulder 36 that bears against the shelf 28 of the body when the cap is inserted in the opening. The first end 32 of the cap 16 is slightly smaller than the inner diameter of the end region 26 of the body so that when the cap is fitted on the body, the primary contact between the components is in the area of the shelf 28 and shoulder 36. Likewise, the flange 34 is spaced longitudinally from the shoulder 36 by a distance slightly greater than the distance between the shelf 28 and the end of the body 14 so that intimate contact between the shelf and shoulder can be achieved.

As shown in Fig. 4, the end surface of the shoulder 36 that engages the shelf is preferably roughened to provide material that will melt during welding to provide a positive seal between the components. This roughening can take the form of radially extending ridges 38, the profiles of which are shown in Fig. 5, such that the roughening will contact the ridge 30 on the shelf 28 during welding to concentrate the ultrasonic energy on the points of contact. The material of the ridges 30, 38 melts together during welding to provide the seal between the components.

Returning to Fig. 1 , the ampule 22 is conventional, typically being formed of a frangible material such as glass, and including a closed interior space within which one of the components 20 of the chemiluminescent composition 12 is encapsulated. Preferably, the ampule is initially formed with an open end through which one of the components of the chemiluminescent composition is supplied to the ampule, and the open end is subsequently closed by melting the glass around the opening and allowing it to deform to the final closed condition.

The chemiluminescent composition 12 can include any of several different chemiluminescent compositions known in the art, and preferably includes an activator component 18 and an oxalate component 20. In the illustrated embodiment, the oxalate component 20 is sealed within the ampule during manufacture, and the activator component 18 is sealed within the casing around the outside of the ampule such that the oxalate and activator components are isolated from one another prior to use. When it is time to use the apparatus, the body is flexed until the ampule fractures, releasing the oxalate component so that the components can mix together and luminesce. An arrangement for use in manufacturing a chemiluminescent light apparatus in accordance with the preferred method of the present invention is illustrated in Fig. 7, and broadly includes a turntable 40 supported for rotation about a vertical central column or post 42, a plurality of stations 44, 46, 48, 50, 52, 54 surrounding the turntable at which the various steps of the method are carried out, and a controller 56 for controlling rotation of the turntable and operation of the assemblies.

The turntable 40 is generally planer, and is supported in a substantially horizontal plane for rotation about the post 42. A plurality of receptacles 58 are provided on the turntable, each of which is substantially identical to the others and sized for receipt of an inverted casing body of a chemiluminescent light apparatus. Six such receptacles are illustrated in the preferred embodiment.

The motor for rotating the turntable is controlled by the controller 56 to rotate the turntable in increments such that each of the receptacles 58 are successively indexed between the stations. After each incremental rotation of the turntable is completed, the motor is stopped for a period of time sufficient to allow the various operations to be completed at the stations. This sequence is repeated indefinitely so that each receptacle is cycled past all of the stations during each revolution of the turntable.

The station 44 is provided with a bin 60 in which a supply of casing bodies is stored, and a dispenser 62 for delivering one body at a time, in an inverted orientation, to the receptacle 58 positioned at the station 44. Although the dispenser 62 is illustrated as being automated, it is understood that the station 44 could alternately be manned such that the operator would manually remove bodies from the bin 60 and position them in the receptacles as the turntable is rotated.

The station 46 includes a bin 64 in which a supply of ampules is stored, and a dispenser 66 for delivering one ampule at a time into the interior cavity of the inverted body supported in the receptacle positioned at the station 46. Although an automated dispenser is illustrated in the assembly, it is possible to manually dispense the ampules, if desired. The steps employed in filling the ampules with one of the chemiluminescent composition components 18, 20 are conventional, and may be carried out at any time prior to use of the ampules in the inventive method.

The station 48 includes a storage container 68 in which a supply of the second chemiluminescent composition component is stored, and a dispenser 70 for dispensing a predetermined volume of the fluid into the interior cavity of the inverted body supported in the receptacle positioned at the station 48. Preferably, the dispenser 70 includes a line connected to the container 68 and presenting a free end positioned over the station, and a valve 72 that is controlled by the controller 56 to open for a period of time gauged to dispense the desired amount of fluid. Pressure can be applied to the fluid either by gravity, a pump or the like.

The station 50 includes a bin 74 in which a supply of caps is stored, and a dispenser 76 for fitting one cap at a time in the open end of the inverted body supported in the receptacle aligned with the assembly. Although the station 50 is illustrated as being automated, it is understood that it could alternately be manned such that the operator would manually remove caps from the bin 74 and position them in the opening of the bodies each time the turntable is indexed.

The station 52 includes a sonic welder 78 having a horn supported on a carriage that moves vertically between an operating position in which the horn is positioned close to the cap on the body supported in the receptacle positioned at the station, and a raised storage position in which the turntable is free to rotate. The sonic welder 78 generates a predetermined amount of ultrasonic energy, and the horn focuses the energy on the area of engagement between the cap and body positioned at the station 52 so that the material of the cap and body melt, forming a seal between the components. The energy is concentrated on the shelf and shoulder of the casing due to the intimate physical contact between the ridge of the shelf and the roughened surface of the shoulder, ensuring that a complete seal is provided around the circumference of the body within a plane extending generally transverse to the longitudinal axis of the body as shown in Fig. 6. Returning to Fig. 7, the station 54 includes an unloading mechanism 80 that removes the completed light apparatus from the receptacle positioned at the unloading station 54. Preferably, the mechanism 80 includes a pneumatic ejection assembly that draws the completed apparatus positioned at the station 54 into a conveyance tube 82 such that the apparatus is transported to a storage location for packaging and shipment. Alternately, the unloading station could be manned such that a person attending the station would manually remove the completed apparatus from the turntable and place it into a suitable bin for packaging and shipment.

The method of manufacturing a single light apparatus in accordance with the preferred embodiment includes the initial step of positioning a light-transmissive body in the receptacle of the turntable disposed at the loading station 44, and indexing the turntable 40 in a counterclockwise direction to position that receptacle at the ampule loading station 46. The turntable 40 is then stopped while an ampule is placed in the interior cavity of the body supported in the receptacle. At the same time, another body is positioned in another of the receptacles of the turntable that is aligned with the loading station. The turntable 40 is subsequently indexed again in the counterclockwise direction until the first receptacle is moved from the ampule loading station 46 to the fluid dispensing station 48. The turntable is again stopped, and the second fluid component of the chemiluminescent composition is dispensed into the interior cavity of the body. At the same time, another body is positioned in another of the receptacles of the turntable that is aligned with the loading station, and an ampule is placed in the body supported in the receptacle positioned at the station 46.

Upon completion of the foregoing steps, the turntable is again indexed until the first-loaded receptacle is brought to the cap fitting station 50, and is stopped while a cap is fitted on the opening of the body positioned at the station 50. At the same time, the stations 44, 46, 48 are activated to carry out their respective operations on others of the bodies positioned thereat.

After these operations are completed, the turntable is indexed again to position the first-loaded receptacle at the welding station 52. After the turntable is stopped in this position, the horn of the welder 78 is lowered to its operating position, and the cap and body are welded together, completing manufacture of the apparatus. Once the operations of the various assemblies 44, 46, 48, 50, 52 is completed, the turntable is again indexed, positioning the first-loaded receptacle at the unloading station 54. The turntable is stopped, and the completed apparatus is unloaded from the turntable and stored for packaging. As with during each subsequent stop of the turntable, all of the stations 44, 46, 48, 50, 52, 54 are activated by the controller 56 to simultaneously perform their respective operations, resulting in a continuous operation in which a completed apparatus is unloaded each subsequent time the turntable is indexed.

Although the present invention has been described with reference to the preferred embodiment illustrated in the attached drawing figures, it is noted that substitutions may be made and equivalents employed herein without departing from the scope of the invention.

Claims

IN THE CLAIMS

1. A chemiluminescent light apparatus comprising: an elongated light-transmissive body defining a longitudinal axis and presenting an interior cavity, the body including an end wall presenting an opening that communicates with the cavity, the opening being stepped to define a shelf that is disposed in a plane generally transverse to the longitudinal axis of the body; a cap received in the opening of the body, the cap including a first stepped region sized for receipt in the opening of the body, the stepped region presenting a shoulder that is sealed against the shelf of the opening to close off the interior cavity of the body; a chemiluminescent composition including first and second fluid components, the first fluid component being enclosed in the interior cavity of the body; and a hollow frangible ampule enclosed in the interior cavity of the body, the ampule defining a closed interior space that is isolated from the first composition, the second fluid component being enclosed in the interior space of the ampule such that when the ampule is fractured, the first and second fluid components mix together and luminesce.

2. The apparatus as recited in claim 1 , wherein the cap includes a first end sized for receipt in the opening of the body and a second end opposite the first end, the stepped region being disposed intermediate the first and second ends.

3. The apparatus as recited in claim 1 , wherein the body includes an annular ridge protruding axially from the shelf prior to manufacture, and the shoulder of the cap includes a roughened surface aligned with the ridge during manufacture.

4. A method of manufacturing the apparatus as recited in claim 1 , comprising the steps of: positioning the body on a rotatable turntable with the opening facing upward; indexing the turntable to an ampule loading station; positioning the ampule in the interior cavity of the body at the ampule loading station; indexing the turntable to a fluid dispensing station; dispensing the second fluid component into the interior cavity of the body at the fluid dispensing station; subsequent to the foregoing steps, indexing the turntable to a cap fitting station; positioning the cap in the opening of the body at the cap fitting station; indexing the turntable from the cap fitting station to a welding station; ultrasonically welding the cap to the body at the welding station to form a complete light apparatus, the shoulder and the shelf being sealed together around the circumference of the cap to seal the interior cavity against leakage of the fluid components; indexing the turntable to an unloading station; and unloading the light apparatus from the turntable.

5. The method of claim 4, wherein the body includes an annular ridge protruding axially from the shelf, and the shoulder of the cap includes a roughened surface that is engaged by the ridge when the cap is positioned in the body opening, the ridge and roughened surface defining an energy concentration zone within which the cap seals to the body during the welding step.

6. A method of manufacturing a chemiluminescent light apparatus, comprising the steps of: positioning a light-transmissive body on a rotatable turntable, the body defining an interior cavity and including an end wall presenting an opening that communicates with the cavity, the opening being stepped to define a shelf that is generally parallel to and spaced from the end wall; indexing the turntable to an ampule loading station; positioning a hollow frangible ampule in the interior cavity of the body at the ampule loading station, the ampule defining a closed interior space in which a first fluid component is stored; indexing the turntable to a fluid dispensing station; dispensing a second fluid component into the interior cavity of the body at the fluid dispensing station; subsequent to the foregoing steps, indexing the turntable to a cap fitting station; positioning a cap in the opening of the body at the cap fitting station, the cap including a first end and an intermediate stepped region sized for receipt in the opening of the body, the intermediate stepped region presenting a shoulder that bears against the shelf of the opening to close off the interior cavity of the body; indexing the turntable from the cap fitting station to a welding station; ultrasonically welding the cap to the body at the welding station to form a complete light apparatus, the shoulder and the shelf being sealed together around the circumference of the cap to seal the interior cavity against leakage of the fluid components; indexing the turntable to an unloading station; and unloading the light apparatus from the turntable.

7. The method of claim 6, wherein the body includes an annular ridge protruding axially from the shelf, and the shoulder of the cap includes a roughened surface that is engaged by the ridge when the cap is positioned in the body opening, the ridge and roughened surface defining an energy concentration zone within which the cap seals to the body during the welding step.