Abstract:
A hot melt adhesive dispensing system comprises a remote metering station for receiving a supply of hot melt adhesive material from an adhesive supply unit (ASU), a plurality of applicator heads for depositing hot melt adhesive material onto different substrates, and a plurality of relatively short hose structures respectively fluidically inter-connecting the remote metering station to the plurality of applicator heads. Oppositely disposed terminal end portions of each one of the relatively short hose structures are respectively provided with universal connectors so as to effectively overcome or counteract the inherent inflexibility characteristic of the relatively short hose structures per se and thereby in fact permit the plurality of applicator heads to be moved to different locations, depending upon the various different requirements attendant particular hot melt adhesive deposition requirements, in order to perform a particular hot melt adhesive deposition operation.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to hot melt adhesive dispensing systems, and more particularly to a new and improved hot melt adhesive dispensing system wherein the hot melt adhesive dispensing system comprises a remote metering station for receiving a supply of hot melt adhesive material from an adhesive supply unit (ASU), a plurality of applicator heads for dispensing or depositing hot melt adhesive material onto different products or substrates, and a plurality of relatively short hose structures for respectively fluidically interconnecting the output ports of the remote metering station to the input ports of the plurality of applicator heads. In view of the fact that relatively short hose structures are inherently inflexible, the oppositely disposed terminal end portions of each one of the plurality of relatively short hose structures are respectively provided with universal connectors so as to in fact effectively overcome or counteract the inherent inflexibility characteristic of the relatively short hose structures per se that respectively fluidically interconnect the plurality of hot melt adhesive material output ports of the remote metering station to the plurality of input ports of the applicator heads, and thereby permit the plurality of applicator heads to be moved to various different positions or locations depending upon the various different requirements attendant particular hot melt adhesive material deposition operations. 
       BACKGROUND OF THE INVENTION 
       [0002]    In connection with liquid dispensing assemblies, and more particularly, in connection with liquid dispensing assemblies which are being used to dispense hot melt adhesives or other thermoplastic materials, a typical dispensing assembly conventionally comprises a supply source of the hot melt adhesive or thermoplastic material, and means for precisely or accurately metering and pumping the hot melt adhesive or thermoplastic material toward an applicator head or dispensing assembly. In connection with particular applications or procedures, it is necessary to accurately or precisely meter the hot melt adhesive or thermoplastic material being dispensed so as to ensure that a specific or predetermined volume of the hot melt adhesive or thermoplastic material is in fact dispensed within a specific or predetermined period of time. For example, in connection with the dispensing of hot melt adhesive materials, it is often necessary to provide a plurality of individual metering pumps for providing predetermined volumes of the hot melt adhesive material, which may in fact comprise similar or different volume quantities or amounts, to discrete, separate, or respective applicator heads or dispensing outlets. More particularly, it is desirable to have a gear pump assembly, for use in connection with a hot melt adhesive dispensing assembly, wherein the hot melt adhesive dispensing assembly comprises a plurality of rotary, gear-type pump assemblies mounted upon the hot melt adhesive dispensing assembly such that all of the rotary, gear-type pump assemblies are independent with respect to each other, wherein the plurality of rotary, gear-type pump assemblies are operatively driven by means of a common rotary drive shaft in such a manner that no external dynamic seals are required, wherein any particular one of the rotary, gear-type pump assemblies can be readily removable from the array or bank of rotary, gear-type pump assemblies independently of the other rotary, gear-type pump assemblies, and can be subsequently re-inserted into the array or bank of rotary, gear-type pump assemblies, or replaced by means of a new rotary, gear-type pump assembly, and wherein still further, as a result of the plurality of rotary, gear-type pump assemblies being independent with respect to each other and not being operatively driven by means of, or mounted upon, a common internally disposed rotary drive shaft, then should a particular one of the rotary, gear-type pump assemblies experience a failure, the failed rotary, gear-type pump assembly would not experience additional damage or cause the other rotary, gear-type pump assemblies to experience freezing or failure. 
         [0003]    Such rotary, gear-type pump assemblies are disclosed within U.S. Pat. No. 6,688,498 which issued to McGuffey on Feb. 10, 2004, which patent is hereby incorporated herein by reference. While the aforenoted gear pump assemblies of McGuffey were disclosed within the aforenoted U.S. Pat. No. 6,688,498 as being utilized in an integral manner with a hot melt adhesive applicator head or dispensing assembly as a result of, for example, being mounted directly upon the applicator head or dispensing assembly, circumstances may arise when it is not possible or practical to utilize such rotary, gear-type pump assemblies in an integral manner with a hot melt adhesive applicator head or dispensing assembly. One possible instance may be, for example, wherein all of the applicator heads or dispensing nozzles are not disposed at one location. In this instance, the applicator heads or dispensing nozzles are to be fluidically connected to the aforenoted rotary, gear-type pump assemblies by means of suitable hose structures for conveying the hot melt adhesive material from the plurality of rotary, gear-type metering pumps to the applicator heads or dispensing nozzles. 
         [0004]    However, it is undesirable that such hose structures have substantially large or elongated lengths in that predeterminedly desired pressure levels, and precisely metered or predetermined volumes of the hot melt adhesive material, are difficult to attain and maintain within such hose structures when the hose structures comprise substantial or significant length dimensions. It is therefore desirable to utilize a metering station which can effectively be located remotely from a source or supply of the hot melt adhesive material, and wherein further, the hot melt adhesive material remote metering station can then be respectively fluidically connected to the plurality of applicator heads or dispensing nozzles by means of relatively short hose structures. In this manner, predeterminedly desired pressure levels, and precisely metered or predetermined volumes of the hot melt adhesive material, can be achieved and maintained such that precisely metered or predetermined volumes of hot melt adhesive material can in fact be dispensed onto predetermined substrate locations. The use of relatively short hose structures, however, nevertheless results in the manifestation of additional problems. For example, it is often the case that the applicator heads need to be moved from one position to another depending upon the different products or substrates, and their inherent structural regions or locations, onto which the hot melt adhesive material is to be dispensed or deposited. Alternatively, the applicator heads may need to be moved from one position to another depending upon the size of the different products or substrates, or still yet further, the applicator heads may need to be moved from one position to another depending upon the particular pattern of hot melt adhesive material to be applied to the particular product or substrate. However, the problem that arises in connection with the use of such relatively short hoses is that they are inherently relatively inflexible, and therefore, the various applicator heads are not always able to be readily or easily moved to their desired positions or locations in order to in fact perform or achieve the desired dispensing or deposition of the hot melt adhesive material onto the particular regions of the particularly configured or particularly sized products or substrates. 
         [0005]    A need therefore exists in the art for a new and improved hot melt adhesive dispensing system wherein, in connection with a remote metering station for receiving hot melt adhesive material from an adhesive supply unit (ASU), a plurality of applicator heads for dispensing or depositing hot melt adhesive material onto particular products or substrates in accordance with predetermined patterns, and a plurality of relatively short hoses for respectively fluidically interconnecting the hot melt adhesive material output ports of the remote metering station to the hot melt adhesive material input ports of the plurality of applicator heads, wherein means will be provided for effectively imparting flexibility to the aforenoted hose connections at both the plurality of output ports of the remote metering station and the plurality of input ports of the plurality of applicator heads so as to effectively overcome or counteract the inherent inflexibility characteristic of the relatively short hoses per se which respectively fluidically interconnect the hot melt adhesive material output ports of the remote metering station to the hot melt adhesive material input ports of the plurality of applicator heads. 
       SUMMARY OF THE INVENTION 
       [0006]    The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved hot melt adhesive material dispensing system which comprises a remote metering station for receiving a supply of hot melt adhesive material from an adhesive supply unit (ASU), a plurality of applicator heads for dispensing or depositing hot melt adhesive material onto different products or substrates, and a plurality of relatively short hose structures for respectively fluidically interconnecting the output ports of the remote metering station to the input ports of the plurality of applicator heads. In view of the fact that relatively short hose structures are inherently inflexible, the oppositely disposed terminal end portions of each one of the plurality of relatively short hose structures are respectively provided with universal connectors so as to in fact effectively overcome or counteract the inherent inflexibility characteristic of the relatively short hose structures per se that respectively fluidically interconnect the plurality of hot melt adhesive material output ports of the remote metering station to the plurality of input ports of the applicator heads, and thereby permit the plurality of applicator heads to be moved to various different positions or locations depending upon the various different requirements or parameters attendant particular hot melt adhesive material deposition operations. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Various other features and attendant advantages of the present invention will be more fully appreciated from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein: 
           [0008]      FIG. 1  is a top plan view of a new and improved hot melt adhesive material dispensing system constructed in accordance with the principles and teachings of the present invention and showing the cooperative parts thereof; and 
           [0009]      FIG. 2  is a side elevational view of the new and improved hot melt adhesive material dispensing system as disclosed within  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0010]    Referring now to the drawings, and more particularly to  FIGS. 1 and 2  thereof, a new and improved hot melt adhesive material dispensing system, constructed in accordance with the principles and teachings of the present invention, is disclosed and is generally indicated by the reference character  10 . More particularly, it is seen that the new and improved hot melt adhesive material dispensing system  10  comprises an inlet port  12  which is adapted to be fluidically connected, by means of a suitable supply hose, not illustrated, to a remotely located adhesive supply unit (ASU), also not illustrated, whereby a supply of hot melt adhesive material is able to be supplied to the hot melt adhesive material dispensing system  10 . The inlet port  12  is mounted upon a filter block  14  within which there is disposed a pair of filter assemblies  16 , 18 , and the filter block  14  is mounted upon a drive gear manifold  20  upon which a plurality of rotary, gear-type metering pump assemblies  22  are mounted so as to collectively effectively form or define a remote, hot melt adhesive material metering station  23 . While any number of rotary, gear-type metering pump assemblies  22  may be mounted upon the drive gear manifold  20 , eight rotary, gear-type metering pump assemblies  22  are illustrated, it being further appreciated that each one of the rotary, gear-type metering pump assemblies  22  effectively comprises a three-piece or three-plate sandwich construction within which the various gear members, comprising each one of the rotary, gear-type metering pump assemblies  22 , are disposed. It is also seen that a plurality of pressure monitoring devices or mechanisms  24  are disposed atop the drive gear manifold  20 , and that a plurality of hot melt adhesive material outlet port housings or transfer blocks  26 , that is, eight outlet port housings or blocks, are adapted to be respectively fluidically connected to each one of the plurality of rotary, gear-type metering pump assemblies  22  through means of suitable fluid passageways, not illustrated, which are defined within the drive gear manifold  20 . Still further, a drive motor  28  is adapted to be operatively connected, through means of a gear box  30  and a coupling  32 , to a drive shaft, not illustrated, which is disposed within the drive gear manifold  20  and which is adapted to be operatively connected to each one of the plurality of rotary, gear-type metering pump assemblies  22 , and it is also seen that an electrical junction box  34 , for providing electrical power to the drive motor  28 , and a pressure transducer  36  are operatively associated with the motor drive system. 
         [0011]    Continuing further, it is also seen that a plurality of hot melt adhesive material applicator heads  38  are adapted to be respectively fluidically connected to selected ones of the hot melt adhesive material outlet port housings  26  by means of suitable hose connections  40 , and that each one of the hot melt adhesive material applicator heads  38  is seen to comprise a module  42 , a dispensing nozzle  44 , and a strand guide  46 . A first supply air coupling  48  is provided upon each one of the applicator heads  38  so as to respectively supply air into each applicator head  38  for mixture with the incoming hot melt adhesive material being supplied to each one of the applicator heads  38  from a respective one of the rotary, gear-type metering pump assemblies  22 , and a first electrical connector for electrical connection to a supply air pre-heater mechanism, not illustrated, is disclosed at  50 . Each applicator head  38  also comprises a hot melt adhesive material manifold  52 , and a filter block  54 , having a filter assembly  56  mounted thereon, is fixedly mounted upon the hot melt adhesive material manifold  52 . In addition, a second electrical connector for electrical connection to a hot melt adhesive material pre-heater mechanism, not illustrated, is disclosed at  58 , and second and third air couplings  60 , 62  are provided for conducting control air into the hot melt adhesive material manifold  52  in order to control the disposition of the hot melt adhesive material dispensing control valve mechanism, not illustrated, disposed within the hot melt adhesive material manifold  52  for controlling the dispensing of the hot melt adhesive material to the output or dispensing nozzle  44 . 
         [0012]    As can readily be appreciated from  FIGS. 1 and 2 , each one of the hose connections  40  respectively fluidically connecting a selected one of the rotary gear-type metering pump assemblies  22  of the hot melt adhesive material remote metering station to one of the applicator heads  38  is characterized by means of a relatively short or small length dimension, such as, for example, within the range of four inches (4.00″) to four feet (4.00″). It will be recalled that the hose connections or structures which fluidically interconnect the rotary gear-type metering pump assemblies  22  and the applicator heads  38  should preferably not have substantially large or elongated length dimensions in that predeterminedly desired pressure levels, and precisely metered or predetermined volumes, of the hot melt adhesive material, are difficult to attain and maintain within such hose structures or connections when the hose structures or connections comprise substantial or significant length dimensions. It is therefore desirable to utilize relatively short hose connections or structures such that predeterminedly desired pressure levels, and precisely metered or predetermined volumes of the hot melt adhesive material, can in fact be achieved and maintained whereby, in turn, precisely metered or predetermined volumes of hot melt adhesive material can in fact be dispensed onto predetermined substrate locations. 
         [0013]    The use of relatively short hose structures or connections, however, nevertheless ordinarily results in the manifestation of additional problems. For example, it is often the case that the applicator heads  38  need to be moved from one position to another depending upon the different products or substrates, and the inherent structural regions or locations onto which the hot melt adhesive material is to be dispensed or deposited. Alternatively, the applicator heads  38  may need to be moved from one position to another depending upon the size or configuration of the different products or substrates, or still yet further, the applicator heads  38  may need to be moved from one position to another depending upon the particular pattern of hot melt adhesive material to be applied or deposited onto the specific product or substrate. However, the problem that arises in connection with the use of such relatively short hose structures or connections is that they are inherently relatively inflexible, and therefore, the various applicator heads  38  are not always able to be readily or easily moved to their desired positions or locations in order to in fact perform or achieve the desired dispensing or deposition of the hot melt adhesive material onto the particular regions of the particularly configured or particularly sized products or substrates, or in accordance with particularly desired or required hot melt adhesive material deposition patterns. 
         [0014]    In accordance with the principles and teachings of the present invention, however, the aforenoted difficulties, normally heretofore encountered in connection with the use of such relatively short hose structures or connections, are advantageously resolved in view of the fact that, as can best be seen from  FIGS. 1 and 2 , the oppositely disposed terminal end portions  64 , 66  of each one of the hose structures or connections  40  are respectively provided with swivel connectors. More particularly, each one of the swivel connectors comprises a universal connector comprising, for example, a ball member disposed within a spherical socket or housing  68 , 70  wherein, for example, each one of the universal ball and socket housings  68  is fixedly attached to or mounted upon a respective one of the applicator heads  38  so as to also be fluidically connected thereto, while each one of the universal ball and socket housings  70  is fixedly attached to, mounted upon, or incorporated within each one of the hot melt adhesive material outlet port housings or transfer blocks  26  so as to likewise be fluidically connected thereto. Each one of the ball and socket housings or assemblies  68 ,  70  therefore permits the ball member thereof, fixedly mounted upon each oppositely disposed terminal end portion  64 ,  66  of each one of the hose structures or connections  40  to be movable within a field or range of movement comprising six degrees of freedom, as defined about or around three mutually orthogonal axes. 
         [0015]    Accordingly, as can best be appreciated from  FIG. 1 , each one of the hose structures or connections  40  is able to be independently movable relative or with respect to its respective applicator head  38  as a result of the universal connection of its terminal end portion  64  to the applicator head  38  as permitted by means of the ball and socket housing assembly  68 , while simultaneously therewith, each one of the hose structures or connections  40  is likewise able to be independently movable relative or with respect to the remote metering station  23  as a result of the universal connection of its terminal end portion  66  to the remote metering station  23  as permitted by means of the ball and socket housing assembly  70 . It can therefore be appreciated still further that each one of the applicator heads  38  is able to be moved within the aforenoted field or range of movement, comprising the six degrees of freedom, with respect to the remote metering station  23 , as a result of the compound movements of the hose structures or connections  40  as facilitated by means of the universal connectors  68 , 70 . Considered from an alternative, but similar, point of view, the applicator heads  38  are effectively provided with a requisite amount of flexibility so as to be capable of being moved to various different positions or locations, as required or desired, depending upon the various different requirements or parameters attendant particular hot melt adhesive material deposition operations, so as to in fact achieve hot melt adhesive dispensing at various different product locations or in accordance with various different hot melt adhesive deposition patterns. 
         [0016]    Thus, it may be seen that in accordance with the principles and teachings of the present invention, there has been provided a new and improved hot melt adhesive material dispensing system wherein the oppositely disposed terminal end portions of the plurality of relatively short hose structures or connections, for respectively fluidically interconnecting the output ports of the remote metering station to the input ports of the plurality of applicator heads, are provided with universal ball and socket housings, assemblies, or connectors so as to provide such relatively short hose structures or connections, which are normally inherently inflexible, with enhanced flexibility characteristics. Accordingly, the plurality of applicator heads are able to be moved to various different positions or locations depending upon the various different requirements or parameters attendant particular hot melt adhesive material deposition operations. 
         [0017]    Obviously, many variations and modifications of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein.