Patent Description:
Nowadays various elements and products composed of such elements, in particular upholstered furniture, are more and more often manufactured in such a manner that not only wooden elements but also fabrics and elements made of plastics are joined together by means of adhesive, which to a large extent simplifies the manufacturing of furniture and shortens the time required for its execution. Before elements are joined together, the contacting surfaces must be covered with adhesive which is more and more often sprayed using spray guns of various design.

In the description of patent application <CIT> titled "Spraying gun" is described a spray gun with an improved air control flow distribution to the spray gun nozzle that comprises a die-cast aluminium body and a handle of hard plastics material whereby the body has a spray head and a nozzle. Both of these elements are made from plastics material and have weirs providing an efficient distribution of the flow of air. The aluminium body is permanently joined to the plastics head by a metal ring to provide an efficient mechanical joint and seal between the parts.

In turn, in application description publication W. <NUM> pertaining to a utility model titled "Spray gun" has been disclosed a spray gun for pressure application of semi-fluid plaster or mineral protective and decorative coatings on internal and external facades, having a spray nozzle in the body and closing the spray chamber with attached gravity tank on the one side and a slidingly shaped slider in form of a hollow sleeve from the side of the spray nozzle ending with an outer cone, and on the other hand closed by a plug and having holes in the side wall. The slider is based on the return spring tensioned by the trigger lever of the gun.

International Patent Application Publication <CIT> titled "Polyolefin hot-melt glue having a low reactivation temperature and high heat stability and use thereof for vacuum deep-drawing lamination" teaches a hot-melt glue composition including at least one atactic poly-α-olefin (APAO) that is solid at <NUM>, at least one hydrocarbon resin having a softening point of at least <NUM>, measured in accordance with the ring-and-ball method, and at least one maleic-anhydride-grafted wax having a softening point of not more than <NUM>, measured in accordance with the ring-and-ball method. Said maleic-anhydride-grafted wax is a maleic-anhydride-grafted polypropylene wax or a maleic-anhydride-grafted polyethylene wax, wherein the proportion of the at least one maleic-anhydride-grafted wax in the hot-melt glue composition is at least <NUM>% by weight.

In addition, in publication <CIT> pertaining to a utility model titled "Hot melt adhesive spray gun" is known a hot melt adhesive spray gun comprising a hot-melt adhesive module with a path for conveying the hot-melt adhesive, an air feed mechanism, a heating module for heating the adhesive and a nozzle. The heating module comprises a heat conductor transferring the heat to a spray gun surface from a heating element embedded in the heat conductor. The heat conductor and a spray gun rear end face transferring the heat extend outside forming two heat-isolating ribs for heat transfer.

In addition, from publication <CIT> pertaining to a utility model titled "Hot melt adhesive machine" is known a hot-melt glue device comprising a gun body, a power unit, a melting tank and a throat for providing a melted glue to the gun body from the tank for melting the glue. The melted glue is conveyed to the gun body under pressure using the power unit.

Furthermore, Publication of European Patent Application No. <CIT>, that pertains to an invention titled "Spray head for spraying a thermoplastic material, particularly a fusible glue", teaches a spray head having at least one feed channel for a heated hot-melt adhesive, an outlet at the lower end of the feed channel, a tapered feed channel for a stream of gas, a mixing chamber into which both the feed channel for the heated hot-melt adhesive and the gas feed channel open as well as a nozzle opening connected to the mixing chamber for the atomized hot-melt adhesive. Outlets of the spray head for gas jets directed onto the emerging atomized hot-melt adhesive are arranged distributed symmetrically round the nozzle opening whereby seen in a plan view on the nozzle openings the gas jets extend from the outlet parallel to one another in pairs and past the nozzle opening and the streams of gas for the mixing chamber on the one hand and the outlets on the other hand are adjustable independently of one another.

US Patent Application Publication No. <CIT> pertaining to an invention titled "Systems and methods for portable multi-component mixing of materials for spray application of same" describes a dual-use, low-pressure spray gun for applying one-component foam as a spray and a bead including a low-pressure canister connector and a low-pressure air hose connector. In addition mentioned publication describes a system for applying one-component spray foam as a spray and a bead including a dual-use spray gun with a low-pressure canister connector and a low-pressure air hose connector, a compressed air supply and a compressed air hose.

Another Publication of European Patent Application No. <CIT> that pertains to an invention titled "Apparatus and methods for application of coatings with supercritical fluids as diluents by spraying from an orifice" discloses a spraying apparatus for coating substrates with a coating material and supercritical fluid. This apparatus is provided with various features, either alone or in combination, to prevent undesirable premature cooling of the coating mixture which might detrimentally affect the final coating on the substrate.

US Patent Description Publication No. <CIT> titled "Hose holder system and related methods" presents a hose holder system that includes a rigid holder having a vertical section and a horizontal section. A flexible sling movably couples with the horizontal section and includes a first flap and a second flap whereas a hose couples with the rigid holder through the sling. The hose is coupled between the first flap and second flap whereby the sling supports a portion of the hose in a position parallel with the horizontal section of the rigid holder. A swiveling base is coupled with the rigid holder and includes an opening therethrough through which the hose passes substantially perpendicularly. In implementations the hose holder system is configured to allow the hose to contact no rigid element of the hose holder system between the opening and a dispenser during use.

Lastly, German Utility Model Description Publication No. <CIT> titled "Leitungsführung für einen mehrachsigen Industrieroboter" pertains to a line arrangement for a multi-axis industrial robot that has a cantilever arm and a robot hand with lines being arranged in a harness and being held in a line holder such that they can move axially with the lines being intended for laying along the cantilever arm as far as the robot hand. In turn, the line holder has a rotating bearing for an arrangement, which can rotate, approximately on the central cantilever arm area and at a short distance from the cantilever arm housing. Additionally flexible-tube buffers, which project like beads, are arranged on the lines.

No one of publication above teaches how to maintain pipe temperature without fear that the hot-melt adhesive will be cooled below to the temperature at which the hot-melt adhesive will be not fluid sufficiently to flow through pipes, especially long pipes, from a melter to a gun.

It is an object of the present invention to provide a system, that would allow for precise applying the hot-melt adhesive onto choosen and exactly defined surfaces to be glued as well as for providing a hot-melt adhesive which can be sprayed using above mentioned system and a method for spraying hot-melt adhesive onto glued surfaces by use of the system for spraying hot-melt adhesive mentioned earlier that in considerably way lightens working persons at furniture manufacturing, especially upholstery furniture.

According to the invention, this object is solved on the one hand by a system having the features of claim <NUM>. The preferred embodiments of the invention are specified in the dependent claims.

The system according to the invention is characterized in that a hot-melt adhesive sprayed onto glued surfaces has a steady temperature that is predetermined and maintained thanks to a hose design, in which an air pipe feeding the air is integrated with a pipe through which flows the hot-melt adhesive, whereby both pipes have predetermined throughput and are fitted in one insulating layer of housing.

Thanks to this design of connecting hose the hot-melt adhesive needs only little to warm up in the spraying gun as the temperature decreasing of adhesive fed using the connecting hose is small and reaches at least a few degrees of Celsius.

According to the invention the pipe, through which the hot-melt adhesive flows with a viscosity between <NUM> mPa*s and <NUM> mPa*s at a temperature between <NUM> and <NUM> and a density between <NUM>,<NUM>/dcm<NUM> and <NUM>,<NUM>/dcm<NUM>, and the air pipe are fitted in an insulating layer of a connection hose
The throughput of the pipe through which the heated hot melt adhesive flows is between <NUM>,<NUM>/h and <NUM>,<NUM>/h, while the throughput of the air pipe is between <NUM>,<NUM><NUM>/min and <NUM>,<NUM><NUM>/min. Futhermore, at least one heater and at least one temperature sensor are located inside the gun's walls, which are in contact with a hot-melt adhesive container, and the heater and the temperature sensor are fitted in the recesses placed in a wall separating the hot melt adhesive container from an inner chamber of the gun.

It is thereby particularly advantageous that the connection hose is suspended by means of a system for suspending flexible elements comprising a holder for holding at least one flexible element, whereby the holder is attached to a mobile system movable along a boom which is attached to a stand by means of an adjusting system that is mounting of boom to a movable construction or a fixed element. Thanks to the suspension of the connection hose, a hose and gun weight is transferred to the construction of mobile system and makes the maintenance work of the gun more ergonomic as compared to known solutions.

According to one of preferred embodiments a particularly efficient operation of the device according to the invention can be seen in that the holder comprises at least one spring loosely and moveable wound on the connection hose, which is suspendly mounted by means of at least one hanger to at least one mobile system, whereby one ends of the hangers are fixed to the mobile system whereas the other ends of the hangers are fixed to the spring at its ends or midpoint.

A further improvement can be achieved in that the adjusting system comprises a stand with a pole and at least two clamps seated on the stand's pole and a mandrel to which the boom is attached, whereby the clamps, that are adjustably fixed along the stand's pole by a screw, have seats in which the ends of the mandrel are pivotally seated around its vertical axis.

Yet a further improvement can be achieved in that the mobile system comprises a longitudinal bearing with a circular internal or rectangular cross-section having multiple rows of balls preferably spaced evenly at a predetermined distance around a circumference of a bearing interior and in contact with an outer surface of the boom, and which is loosely fitted on the boom, and which is placed in a housing with either snap-in holders or slings.

Another preferred development of the invention foresees that the pipe through which heated hot-melt adhesive flows is placed adjacent to the air tube, and comes into contact with the air pipe in the section of the connection hose where an insulating layer of the hose is fitted.

Yet further preferred development of the invention foresees that the air pipe is placed inside the tube through which the heated hot-melt adhesive flows along the section of the connection hose where an insulating layer of the hose is fitted.

Next preferred development of the invention foresees that the pipe through which the heated hot-melt adhesive flows is placed inside the air pipe along the section of the connection hose where an insulating layer of the hose is fitted.

A further improvement can be achieved in that the pipe through which the heated hot-melt adhesive flows is connected by a connector to an inlet port with a through-hole connecting the outlet of the tube with the hot-melt adhesive container located in the front part of the gun.

According to another design of the invention it is advantageous that the heater is placed immediately adjacent to the gun nozzle and the temperature sensor is directly connected to the temperature controller of the power and control system, which controls the operation of the hot melt adhesive heater located in the melter to allow fast response of the adhesive heater controlled by the power and control system to adhesive temperature fluctuations in the gun container and in the inner chamber of the gun may be placed a button pivotally mounted on the gun housing and protruding partially beyond the housing, to which a pusher with a needle may be attached, the end of which reaches the outlet of hot melt adhesive in order to prevent adhesive from flowing out when the gun is not in use and in the inner chamber of the gun may be situated an internal air line with a valve that cuts off the flow of compressed air through the internal air line by the action of the button on the valve, and the internal air line may connect the air port of the gun with air channels connected to the compressed air outlet.

According to one of embodiments a further improvement can be achieved in that the compressed air outlet are openings in the front wall of the nozzle surrounding the hot melt adhesive outlet that is placed in the center of the nozzle and whereby the outlet of hot-melt adhesive has a truncated cone shape and the air openings have longitudinal symmetrical axes inclined at an angle α to a symmetrical axis of the nozzle, and at least one air opening may have a symmetrical axis within a plane placed at a distance a from the plane passing through the longitudinal symmetrical axis of the nozzle.

A composition of hot-melt adhesive according to the invention is characterised in that the composition of hot-melt adhesive for spraying using the system for spraying hot-melt adhesive onto glued surfaces used in particular for manufacture of upholstery furniture that may comprise not more than <NUM>,<NUM>% of hydrocarbon resin, not more than <NUM>,<NUM>% of polybutene, not more than <NUM>,<NUM>% of antioxidant, not more than <NUM>,<NUM>% of copolymer mixture, and not more than <NUM>,<NUM>% of polyolefin polymer by weight.

Preferred development of the invention foresees that the composition of hot melt-adhesive comprises <NUM>,<NUM>% of hydrocarbon resin, <NUM>,<NUM>% of polybutene, <NUM>,<NUM>% of antioxidants, between <NUM>,<NUM>% and <NUM>,<NUM>% of polyolefin polymer, preferably <NUM>,<NUM>%, and copolymer mixture in an amount complementary to <NUM>,<NUM>% of the components, preferably <NUM>,<NUM>%.

In turn, a method for spraying hot-melt adhesive onto glued surfaces using a system for spraying hot-melt adhesive onto glued surfaces a melter to heat hot melt adhesive, an air compressor, a power and control system, and a gun connected to the melter by a pipe with screw connectors through which the heated hot melt adhesive flows, and connected to the air compressor by an air pipe with screw connectors through which the compressed air flows, and having a nozzle with a hot melt adhesive outlet and a compressed air outlet directed towards surfaces to be bonded, according to the invention is characterised in that to the intake port of the gun through the pipe fitted in a hose inside its insulating layer with a throughput between <NUM>,<NUM>/h and <NUM>,<NUM>/h, is supplied under a pressure of <NUM> kPa to <NUM> kPa, a hot melt adhesive with a viscosity ranging from <NUM> mPa*s to <NUM> mPa*s and a density ranging from <NUM>,<NUM>/dcm<NUM> to <NUM>,<NUM>/dcm<NUM>, preferably from <NUM>,<NUM>/dcm<NUM> to <NUM>,<NUM>/dcm<NUM>, heated to a temperature between <NUM> and <NUM>, and through the air pipe with a throughput of <NUM>,<NUM><NUM>/min to <NUM>,<NUM><NUM>/min, placed in the hose in its insulating layer in the area of the adhesive supply pipe, air is supplied at a pressure of <NUM> kPa to <NUM> kPa to an air ferrule of the gun.

Other characterising features and advantages of the invention will become apparent from the description hereinafter with reference to the attached schematic drawings, which are provided only by way of non-limitative examples of the invention, wherein:.

<FIG> schematically shows one of embodiments of a system <NUM> for spraying a composition of adhesive, specifically a hot-melt adhesive onto glued surfaces according to the invention. The system in its most simplified shape comprises a heating device, specifically a melter <NUM> to heat hot melt adhesive, an air compressor <NUM>, a power and control system <NUM> and a gun <NUM>, <NUM>. To the gun <NUM>, <NUM> is fed the hot-melt adhesive at a temperature of <NUM> in one embodiment, and at a temperature of <NUM> or even <NUM> in another embodiment, and in the preferred embodiment at a temperature of <NUM>, connected by a connection hose <NUM> to the melter <NUM>, equipped with a gear or pressure pump, and an air compressor <NUM>. The power and control system <NUM> is connected to the gun <NUM>, <NUM> by a wiring harness <NUM> terminated by an electrical connector <NUM> with a plug <NUM>, as shown in <FIG>, as well as to the air compressor <NUM> and the melter <NUM>.

The connection hose <NUM> in the embodiment shown in <FIG> is a hose without its own heating and has a pipe <NUM> with screw connectors <NUM>, <NUM> through which the heated hot-melt adhesive flows, and an air pipe <NUM> with connectors <NUM>, <NUM> through which compressed air flows at a pressure of <NUM> kPa in one embodiment, <NUM> kPa in another, and <NUM> kPa in a preferred embodiment. In one embodiment, the air fed to the gun is at an ambient temperature and is pressurized up to <NUM> kPa. The ambient temperature can reach <NUM>, <NUM>, <NUM>, <NUM> and even more degrees Celsius.

Other embodiments of the connection hose are shown in <FIG>. Both the connection hose <NUM> shown in <FIG> and the connection hose <NUM> shown in <FIG> are multi-layered. Depending on the diameter of the air pipe <NUM> and the pipe <NUM> through which the heated hot-melt adhesive flows, the hose <NUM> in <FIG> has an inner diameter of <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even more than <NUM>, which means that the most common inner diameter of the hose is between <NUM> and <NUM>. An outer protective layer <NUM> of the jacket is usually <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. The protective layer <NUM> surrounds an insulating layer <NUM>, in which the air pipe <NUM> and the pipe <NUM>, through which the heated hot melt adhesive flows, and is positioned near the air pipe <NUM> and is in contact with it along the hose <NUM>, along which the insulating layer <NUM> of the hose <NUM> is placed, so that the air pumped into the gun is heated spontaneously by the heated hot-melt adhesive. Common air pipe diameters are <NUM>, <NUM>, <NUM>, and their jacket thickness is <NUM>, <NUM> or <NUM>.

Similarly to the connection hose <NUM> shown in <FIG>, the connection hose <NUM> shown in <FIG> has an outer protective layer <NUM> which surrounds an insulating layer <NUM>. The difference between the two hose embodiments is that an air pipe <NUM> with a connector <NUM> is fitted in a pipe <NUM> with a connector <NUM> through which the heated hot-melt adhesive flows, and separation of the pipes <NUM>, <NUM> at both ends is ensured by splitters <NUM> placed at the end of the insulating layer of the hose <NUM>. In this embodiment, an inner diameter of the pipe, which is an outer pipe, is larger than an outer diameter of the inner pipe, which has a diameter of <NUM>, <NUM>, <NUM>, or <NUM>. In one embodiment, the air pipe <NUM>, <NUM> and the pipe <NUM>, <NUM> through which the heated hot-melt adhesive flows are made of teflon. Both the air pipe <NUM>, <NUM> and the pipe <NUM>, <NUM> through which the heated hot melt adhesive flows are adapted to operate at a temperature up to <NUM> and at a pressure up to <NUM> kPa or even up to <NUM> kPa. In yet another embodiment, the pipe through which the heated hot melt adhesive flows is placed inside the air pipe within a section of the connection hose where the insulating layer of the hose is fitted.

<FIG> schematically represents one embodiment of the gun <NUM> with the connectors <NUM>, <NUM>, <NUM> and <NUM> of the connection hose <NUM>. A more detailed design of the guns <NUM>, <NUM> is shown in <FIG> and <FIG>.

The gun <NUM> shown in <FIG> and <FIG> has a housing <NUM> in an interior of which, in a front part of the gun <NUM>, a hot melt adhesive container <NUM> is fitted, which ensures that the temperature of hot melt adhesive leaving a nozzle of the gun is maintained at a desired and preset value without fear that the hot-melt adhesive will be cooled as it flows through through-holes in the housing of the gun <NUM>. At least one heater <NUM> with a wire <NUM> and at least one temperature sensor <NUM> are fitted in walls of the gun <NUM> that surround the hot melt adhesive container <NUM> with a ferrule <NUM>. The heater <NUM> is placed inside a recess <NUM>, immediately by the nozzle so that adhesive leaving the gun has the same temperature as the gun heater. The temperature sensor <NUM> is placed in a recess <NUM>, and both recesses <NUM>, <NUM> are accessible in particular from a side of wall <NUM> separating the hot melt adhesive container <NUM> from an inner chamber of the gun <NUM> fitted mainly inside a grip part of the gun <NUM>. The temperature sensor <NUM> is directly connected via a wire <NUM> to a temperature controller which controls the heater of hot melt adhesive placed in the melter to allow fast response of the adhesive heater controlled by the power and control system <NUM> to adhesive temperature fluctuations in a gun container, which also improves the temperature stability of adhesive leaving the gun.

In the inner chamber of the gun <NUM> is situated an inner air line <NUM> with an air ferrule <NUM> and a button <NUM> partially protruding beyond the housing <NUM> of the gun <NUM>. The button <NUM> is mounted pivotally in a joint <NUM> in the gun housing <NUM> and is leaned on a spring <NUM>. A pusher <NUM> with a needle <NUM>, the end of which reaches an outlet or orifice <NUM> of the hot melt adhesive, is attached to a part of the push button <NUM> which is placed opposite the hot melt adhesive container <NUM>. The outlet <NUM> of the hot melt adhesive is connected to the hot melt adhesive container <NUM> by a channel <NUM>, through which the hot melt adhesive flows into the outlet <NUM> of the hot-melt adhesive that is closed by the end of the needle <NUM>. When the button <NUM> is pressed, the pusher <NUM> with the needle retracts, which allows the hot-melt adhesive to flow out and be sprayed. In the inner chamber of the gun <NUM>, the inner air line <NUM> is fitted with a cut-off valve <NUM>, cutting off the flow of the compressed air that flows through the inner air line <NUM> upon the action of the button <NUM> on the valve <NUM> through the spring element <NUM>. The above-mentioned inner air line <NUM> connects the air ferrule <NUM> of the gun <NUM> through a connector <NUM> to air ducts <NUM> connected to an outlet <NUM> of the compressed air. The compressed air outlet <NUM> in the embodiments of the invention shown in <FIG> and <FIG> are openings in a front wall <NUM> of a nozzle <NUM>, shown in <FIG>, surrounding the hot-melt adhesive outlet <NUM>.

The gun <NUM> shown in <FIG> is similarly designed to the gun <NUM> in <FIG> and has a housing <NUM>, inside of which there is a container <NUM> of the hot-melt adhesive fitted at the front of the gun <NUM> and an inner air pipe connecting an air connector <NUM> to air ducts <NUM> and a button <NUM>. In this embodiment, the hot-melt adhesive container <NUM> is much larger than the gun <NUM> container shown in <FIG>, which reduces temperature fluctuations of the hot-melt adhesive leaving an outlet <NUM> of the hot melt adhesive. However, the hot melt adhesive container <NUM> may have smaller dimensions than the gun <NUM> container shown in <FIG>, when the gun is intended for bonding small surfaces, which limits a demand for the adhesive. In such a case, the adhesive is quickly heated to a required temperature, for example after a downtime.

In walls of the gun <NUM>, which surround the hot melt adhesive container <NUM> with a screw connector <NUM>, heaters <NUM>, <NUM> and temperature sensors <NUM>, only one of which is shown in <FIG>, are located. The heater <NUM> with wires <NUM> is fitted in a recess <NUM>, and the temperature sensors <NUM> with wires <NUM> are fitted in recesses <NUM> which are positioned in particular in a wall <NUM> separating the hot melt adhesive container <NUM> from an inner chamber of the gun <NUM> placed mainly in a grip part of the gun <NUM>. The heater <NUM> is placed immediately by the nozzle <NUM> of the gun <NUM> and is fitted in a recess <NUM>. Such arrangement of the heater ensures a proper temperature of the adhesive getting out through an opening or openings made in a front wall <NUM> of the nozzle <NUM>. Openings in the front wall <NUM> of the nozzle <NUM> surrounding the hot melt adhesive outlet <NUM> or orifice serve as an outlet of the compressed air.

<FIG> shows a cross-sectional view of a part of the housing <NUM>, <NUM> of the gun shown in <FIG>, <FIG>, and <FIG>, at the point where it is connected by a threaded connection <NUM> to the nozzle selected from the nozzles <NUM>, <NUM>, shown in <FIG>. <FIG> shows in detail the connection of the adhesive container <NUM>, <NUM> with the channel <NUM> through which the hot-melt adhesive flows into the outlet <NUM> closed by the end of the needle <NUM>, and the connection of the air channels <NUM>, <NUM> with inlet channels <NUM> and the air openings <NUM>. The nozzle <NUM>, <NUM> has a seal <NUM> at the side of the gun. The hot melt adhesive outlet <NUM>, situated centrally in a conical protrusion <NUM> of the front wall <NUM>,<NUM>, is surrounded by the air openings <NUM>.

<FIG> show various embodiments of nozzles screwed onto the threaded part of the gun <NUM>, <NUM>. <FIG> shows a front view of one embodiment of the nozzle <NUM>, while <FIG> shows its cross-sectional view. In this embodiment, the nozzle <NUM> with a body <NUM> comprises a hot-melt adhesive through-hole connecting the hot-melt adhesive outlet <NUM> to the hot melt adhesive container <NUM>. The diameter of the opening for hot melt adhesive in the given embodiments is <NUM>, <NUM>, <NUM>, or even <NUM>. On the gun side, the nozzle <NUM> has a seal <NUM>. The hot melt adhesive outlet <NUM>, fitted centrally in a conical protrusion <NUM>, is surrounded by the air openings <NUM> placed in the front wall <NUM> of the nozzle <NUM>, moreover, in this embodiment, the outlet <NUM> is surrounded by twelve air openings <NUM> whose longitudinal symmetry axes are inclined at an angle α to a symmetry axis of the nozzle. In this embodiment, at least one air opening <NUM> has a symmetry axis placed at a distance a from a plane passing through the longitudinal symmetry axis of the nozzle <NUM>. The distance a may equal <NUM>, <NUM>, <NUM>, <NUM>, or even be greater than <NUM>. In yet another embodiment not shown in the figure, the hot melt adhesive outlet is placed centrally in a truncated cone shaped protuberance, and is surrounded by the air openings which are placed in the front wall of the nozzle and whose longitudinal symmetry axes lie in planes passing through the longitudinal symmetry axis of the nozzle. In turn <FIG> shows a front view of yet another embodiment of the nozzle <NUM>, which has six air openings <NUM> surrounding the hot melt adhesive outlet <NUM>. <FIG> shows a cross-sectional view of another embodiment of the nozzle <NUM> with a nut-shaped body <NUM> ended with the front wall <NUM> comprising a conical protrusion <NUM> with a symmetry axis placed in the symmetry axis of the nozzle. On the gun side, the nozzle <NUM> has a seal <NUM>. The hot melt adhesive outlet <NUM> is surrounded by the air openings <NUM> whose longitudinal axes are placed parallelly to the symmetry axis of the nozzle <NUM>. The hot melt adhesive outlet <NUM> in this embodiment has a diameter equal to the diameter of the smaller base of the truncated cone but may also have a smaller diameter. In one embodiment, the vertical angle of the protrusion <NUM> is <NUM>°, in another <NUM>°, then <NUM>° and <NUM>°. In other embodiments, the nozzle has <NUM>, <NUM>, <NUM>, <NUM>, or more air openings. Owing to a greater number of air openings, adhesive may be distributed into small particles with improved efficiency and sprayed onto surfaces to be bonded, which increases the possibility of bonding by applying the adhesive to one of the surfaces to be bonded together, and not as before, when the adhesive had to be applied mostly to both contacting surfaces to be bonded. Moreover, better adhesive breakdown not only results in better bonding quality but also results in limiting the adhesive consumption. The nozzle, having the conical protrusion <NUM>, <NUM>, allows the adhesive to be sprayed from various distances from the surfaces to be bonded, which has not been possible with flat nozzles used so far. Common diameters of the nozzle air openings in the embodiments described above are <NUM>, <NUM>, <NUM>, or even <NUM>.

<FIG> schematically shows another embodiment of the system <NUM> for spraying the hot-melt adhesive on surfaces to be bonded compliant with the invention, which is similar to the system <NUM> for spraying the hot-melt adhesive, shown in <FIG>. The system <NUM> shown in <FIG>, compared to the system <NUM> in <FIG>, additionally has a heater <NUM> of air pressed to the hose <NUM>. The remaining devices, such as the melter <NUM> for heating the hot-melt adhesive, the air compressor <NUM>, the power and control system <NUM>, and the gun <NUM> or <NUM>, connected to the melter <NUM> by the pipe <NUM> with the connectors <NUM>, <NUM>, through which the heated hot-melt adhesive flows, and connected to the air compressor <NUM> by the air pipe <NUM> with the connectors <NUM>, <NUM>, perform similar functions as in the system in <FIG>. In the embodiment shown in <FIG>, the air compressed by the air compressor <NUM> is heated by the air heater <NUM> connected to the air compressor <NUM> by an external air hose <NUM>. Compared to the system in <FIG>, the air heater <NUM> is an accessory.

The connection hose <NUM>, which houses the air pipe <NUM> and the pipe <NUM>, through which the heated hot melt adhesive flows, is suspended by a holder <NUM> of a system <NUM> for suspending flexible elements. The holder <NUM> is movable along an arm <NUM>, which is mounted rotatably around a vertical axis and vertically movable along a stand <NUM> of a system <NUM> for suspending the connection hose <NUM>. The vertical position of the arm <NUM> on the stand <NUM> is determined by clamps <NUM> with a setting screw <NUM>, whereby in seats of clamps <NUM> a spindle is located, which keeps the arm in a horizontal position. Additionally, the horizontal position of the arm <NUM> is maintained by a tensioner <NUM>. The stand <NUM> of this system is seated on a base <NUM> with a weight <NUM>. The stand <NUM> is held in the vertical position by a stay <NUM>. A spring <NUM> of the holder <NUM> is loosely wound on the connection hose <NUM>, which, by means of hangers <NUM>, is suspended to a mobile system <NUM> of the holder <NUM>, in particular to a housing <NUM> of an elongated bearing <NUM> movable along the arm <NUM> and slide-fitted on the arm <NUM>. The hangers <NUM> in this embodiment are bars or pipes.

Construction of the mobile system <NUM>, as well as the bearing <NUM> and its housing <NUM>, is shown in detail in <FIG>. The said bearing <NUM> in this embodiment is loosely fitted on the arm <NUM>, which allows the holder <NUM> of the mobile system <NUM> to move along the arm <NUM>, in particular with a circular cross-section. According to one embodiment, the bearing has a length exceeding an inner diameter of the bearing <NUM>, specifically, the length is three times the inner diameter of the bearing <NUM>. In one embodiment, the bearing length is <NUM> and, in another, the bearing length is <NUM> or even more. The bearing <NUM> has numerous rows of balls preferably evenly spaced at a predetermined distance around the circumference of the bearing interior, which reduces frictional resistance when the bearing is moved along the arm, preferably of circular cross-section. The bearing <NUM> is fitted inside a tube-shaped housing <NUM> and is locked in the housing by a bolt <NUM> with a lock nut <NUM>. In the solution shown in <FIG>, snap-in holders <NUM> are attached to the housing <NUM>, to which upper ends of the hangers <NUM> are attached, the lower ends of which are attached to the spring <NUM> of the holder <NUM>.

<FIG> show in detail another embodiment of a mobile system <NUM> with a bearing <NUM> and its housing <NUM>. Similarly to the bearing <NUM> shown in <FIG>, the bearing <NUM> shown in <FIG> is loosely fitted on one of booms <NUM>, <NUM>, shown in one of <FIG>, which allow movement of the mobile system <NUM>, <NUM> along the boom <NUM>, <NUM>, in particular with a rectangular cross-section. The bearing <NUM> has numerous rows of balls touching an external surface of the boom <NUM>, <NUM>, shown as examples in <FIG>, which are preferably evenly spaced at a predetermined distance in a width at a top and bottom of a bearing interior, which reduces frictional resistance when the bearing is moved along the arm, preferably with a rectangular cross-section. The bearing <NUM> is fitted inside a rectangular-shaped housing <NUM> and is locked in the housing by fixing elements <NUM> and a bolt <NUM> with a lock nut <NUM>. In the solution shown in <FIG>, holders or handles <NUM> with slings are attached to the housing <NUM>. The slings are fixed to the spring <NUM>, <NUM>, <NUM>, according to the solutions shown in <FIG>, <FIG>.

<FIG> represents schematically another embodiment of a system <NUM> for spraying hot-melt adhesive on surfaces to be bonded according to the invention. The system <NUM>, like the systems <NUM>, <NUM> in <FIG> and <FIG>, respectively, comprises the gun <NUM>, <NUM>, <NUM> in various versions as previously described, a heating device, specifically a melter <NUM> for heating hot-melt adhesive, a compressed air supply system <NUM>, specifically an air compressor, and the power and control system <NUM>, <NUM> integrated within the melter <NUM>. The gun <NUM>, <NUM>, <NUM> is provided with the heater <NUM>, the sensor <NUM>, the hot melt adhesive container <NUM>, into the outlet <NUM> of which, closed by the needle, is pumped hot-melt adhesive of a temperature between <NUM> and <NUM> through the tube <NUM> of the connection hose <NUM>, <NUM> shown in <FIG> with a melter container <NUM> of the melter <NUM> for hot-melt adhesive, equipped with an adhesive heater <NUM> and a gear pump <NUM> driven by a motor <NUM> or a pressure pump. In the latter case, the pressure pump is driven by compressed air with an output determined by a pressure regulator interacting with the power and control system <NUM>, <NUM>. The gun <NUM>, <NUM>, <NUM> is connected by the air tube <NUM> through a valve <NUM>, shown in <FIG> in the open position, to an air compressor <NUM> driven by a motor <NUM> of the compressed air supply system <NUM>, powered and controlled by the power and control system <NUM>, <NUM>. Compressed air is supplied through the air channels <NUM> to the openings <NUM> of the nozzle <NUM> of the gun <NUM>, <NUM>, <NUM>. In one of embodiments, the compressed air is heated by an air heater <NUM> shown in Fig. <NUM>, fitted especially in the compressed air supply system <NUM>, operating as an independent unit, or which is arranged in particular in the compressed air supply system <NUM>, powered and controlled by the power and control system <NUM>, <NUM>. Moreover, the gun is connected to a power and control system <NUM>, <NUM> to which, in particular, data is directly transmitted from the sensor <NUM> placed near the outlet <NUM> of the nozzle <NUM> of the gun <NUM>, <NUM>, <NUM>, that can respond to changes of temperature and pressure in the hot melt adhesive container <NUM> of the gun <NUM>, <NUM>, <NUM>. By reading the temperature and/or pressure values and communicating directly with the power and control system <NUM>, <NUM>, it is possible to react quickly to changes in temperature and/or pressure values and to precisely control the adhesive heater <NUM> and the gear pump <NUM> or pressure pump to maintain the adhesive temperature at the outlet <NUM> of the nozzle <NUM> of the gun <NUM>, <NUM>, <NUM> at the most suitable value for hot melt adhesive bonding.

<FIG> represents schematically one of the embodiments of a system <NUM> for suspending flexible elements, especially long flexible elements, in particular hoses. A flexible element within the meaning of the invention is an element which has no permanent form and bends under its own weight. Whereas a long flexible element is an element whose length is several times greater than the largest transverse dimension, for example, more than ten-fold greater. The system <NUM> for suspending flexible elements comprises a holder <NUM> for holding a flexible element <NUM>, for example a rope or a hose, which is attached to the mobile system <NUM>, <NUM> movable along the boom <NUM> which is attached to a stand <NUM>, for example a pole <NUM>, by means of an adjusting system <NUM> allowing for change of the distance of the boom <NUM> from the ground. The holder <NUM> comprises a spring <NUM> wound and movable on a flexible element <NUM>, which means that an inner diameter of the spring <NUM> is larger than an outer diameter of the flexible element <NUM> and the flexible element can move relative to the spring. The spring <NUM> according to the example from <FIG> is suspended to the mobile system <NUM>, <NUM> by at least one suspending element <NUM>, for example a cord or wire with catches, whereby ends from one side of the suspending elements <NUM> are attached to the mobile system <NUM>, <NUM>, while other ends of the suspending elements <NUM> are attached to the spring <NUM> in an area of its center or in an area of its ends. In one of the embodiments, the function of the adjusting system is performed by the fixture of the boom <NUM>, not shown in the drawing, to any movable structure or stationary element, for example a wall. The adjusting system <NUM> shown in <FIG> has at least two clamps <NUM> seated on the pole <NUM> of the stand <NUM> and a mandrel or pin <NUM> to which the boom <NUM> of the mobile system <NUM>, <NUM> is attached. The clamps <NUM>, for example, the upper clamp and the lower clamp, are fixed adjustable along the pole <NUM> of the stand <NUM>, and at least one clamp, preferably the lower clamp, is locked relative to the pole <NUM> by a screw <NUM> at a selected distance from the ground, which prevents the position of the boom <NUM> from changing the selected distance from the ground. In another embodiment, clamps may be replaced by plates that are attached to the moveable structure or wall and that have seats for the mandrel, such as the seats of the clamps <NUM>. The clamps <NUM> have seats <NUM> set off from the post <NUM> in which ends of the mandrel <NUM>, which may move vertically, are pivotally seated around its vertical axis, which is performed by means of at least one screw <NUM> screwed into a threaded through-hole made in at least one clamp. The boom <NUM>, for example a rod or pipe <NUM> of any cross-section, is permanently attached to the mandrel <NUM>. The post has a base <NUM> that may be permanently fixed to the ground or to a movable element, such as a movable pallet or a cart that moves on the ground.

<FIG> shows another embodiment according to the invention of a system <NUM> for suspending very long flexible elements <NUM>, e.g. hoses <NUM>, especially connection hoses, with a connector <NUM> and a valve <NUM>. Due to its build, the system <NUM> enables longer distance transport of the hot melt adhesive. The system <NUM> for suspending long flexible elements comprises holders <NUM>, similar to the holders <NUM> of the system <NUM>, for holding a long flexible element <NUM> in several points, each of which is attached to the mobile system <NUM>, <NUM> movable along a boom <NUM>, which is attached to a stand <NUM> by means of an adjusting system <NUM>. Each holder <NUM> comprises a spring <NUM> wound and movable on the flexible element <NUM>. According to the embodiment shown in <FIG>, each spring <NUM> is suspended to the mobile system <NUM>, <NUM> by at least one suspending element <NUM>. The adjusting system <NUM> shown in <FIG> is similar to the adjusting system <NUM> shown in <FIG> and includes at least two clamps <NUM> seated on a pole <NUM> of the stand <NUM> and a mandrel <NUM> to which the boom <NUM> of the mobile system <NUM>, <NUM> is attached, similarly to the embodiment from <FIG>. The clamps <NUM> are connected by a strut <NUM>, that prevents the mandrel <NUM> from falling out of seats <NUM> of the clamps <NUM>, and at least one of the clamps is locked relative to the pole <NUM> with a base <NUM> by a setting screw <NUM> screwed into a threaded through hole until it touches the pole <NUM>. The boom <NUM>, for example a rod or pipe <NUM> of round or rectangular cross-section, is permanently attached to the mandrel <NUM>.

<FIG> show the clamp <NUM>, <NUM>, that is attached to a stand's pole of one of the adjusting systems <NUM>, <NUM> described above. <FIG> shows a longitudinal section of the clamp <NUM>, <NUM>, <FIG> shows a top view of the clamp shown in <FIG> shows a side view of the clamp shown in <FIG>. The clamp <NUM>, <NUM> has a shape of a rectangular plate <NUM> with a through hole <NUM> whose diameter D corresponds to an outer diameter of the pole, which is seated on the pole of the systems previously described. The diameter D is selected so that the clamp may be moved along the pole on which it is mounted. Moreover, the plate <NUM> has a cylindrical recess <NUM> with a diameter d, which forms a seat <NUM>, <NUM> for seating the mandrel <NUM>, <NUM>, shown in <FIG>, of the systems previously described. The clamp <NUM>, <NUM> may be an upper clamp, in the seat or socket of which the top pivot of the mandrel <NUM>, <NUM> is pivotally seated, and may be a lower clamp, in the socket of which the bottom pivot of the mandrel <NUM>, <NUM> is pivotally seated, which in this embodiment is formed from a rod <NUM> with cylindrical-shaped sections <NUM> at its ends whose diameter d corresponds to the diameter d of the recess <NUM>. Furthermore, the plate has a threaded hole <NUM> from its front side, into which a screw is screwed to lock the clamp relative to the pole on which the clamp is mounted. In one of the embodiments of the boom fixing to a movable structure or a stationary element, plates similar to the plate <NUM> shown in <FIG>, comprising sockets only, are permanently fixed to the movable structure or the stationary element at such a distance that the mandrel to which the boom is attached has the ability to rotate around its own vertical axis.

With a system for suspending flexible elements that connect movable components and equipment, it is not necessary to remove the flexible elements from one set of holders and hang them from another when the distance between the components and equipment changes because the sections of the flexible elements may move together with the holders attached to the mobile systems that move on the booms.

The adhesive used for gluing elements, especially those such as furniture upholstery elements, as well as those made of polyurethane foam, wood, metal, plastics, may be bonded with any hot melt adhesive. Composition of the adhesive has been shown in one of embodiments in <FIG>.

In particular, the hot-melt adhesive composition is suitable for gluing using the system proposed by the invention or according to the invention, in particular the hot-melt adhesive containing by weight not more than <NUM>% of hydrocarbon resin, not more than <NUM>% of polybutene, not more than <NUM>% of antioxidant, not more than <NUM>% of copolymer mixture, and not more than <NUM>% of polyolefin polymer. In one preferred embodiment, the hot-melt adhesive comprises <NUM>% and, in another, <NUM>% of hydrocarbon resin, in general between <NUM>% and <NUM>% of hydrocarbon resin, <NUM>% and, in another, <NUM>% of polybutene, in general between <NUM>% and <NUM>% of polybutene, <NUM>% and, in another, <NUM>% of antioxidants, in general between <NUM>% and <NUM>% of antioxidants, <NUM>%, and, in another, <NUM>% of polyolefin polymer, in general between <NUM>% and <NUM>% of polyolefin polymer, and copolymer mixture in an amount complementary to <NUM>% of the components, i.e., a copolymer mixture of <NUM>%, and, in another, <NUM>%, in general between <NUM>% and <NUM>% of copolymer mixture. In another preferred embodiment, hot melt adhesive comprises <NUM>% of hydrocarbon resin, <NUM>% of polybutene, <NUM>% of antioxidants, <NUM>% of copolymer mixture and <NUM>% of polyolefin polymer by weight. In yet another embodiment, the hot melt adhesive composition comprises <NUM>% of hydrocarbon resin, <NUM>% of polybutene, <NUM>% of antioxidants, <NUM>% of copolymer mixture and <NUM>% of polyolefin polymer by weight.

An antioxidant known in the state of the art may be one of the polymer stabilizing products that is produced by companies, for example BASF, under Irganox trade name, and a copolymer mixture may be a polyolefin mixture. Preferably, the adhesive used for bonding based on the system proposed by the invention should have a viscosity of <NUM> mPa*s, and, in another embodiment, of <NUM> mPa*s, and in general between <NUM> mPa*s and <NUM> mPa*s, at a temperature between <NUM> and <NUM>, and a density of <NUM>/dcm<NUM>, and, in another embodiment, of <NUM>/dcm<NUM>, and in general between <NUM>/dcm<NUM> to <NUM>/dcm<NUM>, preferably between <NUM>/dcm<NUM> and <NUM>/dcm<NUM>.

Claim 1:
A system (<NUM>, <NUM>, <NUM>) for spraying a hot-melt adhesive onto glued surfaces comprising
a melter (<NUM>) to heat the hot-melt adhesive,
an air compressor (<NUM>, <NUM>),
a power and control system (<NUM>, <NUM>) and
a gun (<NUM>, <NUM>) having a nozzle (<NUM>) with a hot-melt adhesive outlet or orifice (<NUM>) and a compressed air outlet (<NUM>) and connected to the melter (<NUM>, <NUM>) by a pipe (<NUM>) with screw connectors (<NUM>, <NUM>), through which a hot-melt adhesive being heated flows, and connected to the air compressor (<NUM>, <NUM>) by an air pipe (<NUM>) with screw connectors (<NUM>, <NUM>) through which a pressurized compressed air flows,
wherein
the pipe (<NUM>), through which flows the hot-melt adhesive having a viscosity between <NUM> mPa*s and <NUM> mPa*s and a temperature between <NUM> and <NUM>, and a density between <NUM>,<NUM>/dcm<NUM> and <NUM>,<NUM>/dcm<NUM>, and the air pipe (<NUM>) are fitted in an insulating layer of a connection hose (<NUM>), and wherein the throughput of the pipe (<NUM>) through which the hot-melt adhesive being heated flows is between <NUM>,<NUM>/h and <NUM>,<NUM>/h, while the air pipe (<NUM>) has a throughput between <NUM>,<NUM><NUM>/min and <NUM>,<NUM><NUM>/min
characterised in that
at least one heater (<NUM>) and at least one temperature sensor (<NUM>) are located inside the gun's (<NUM>) walls, which are in contact with a hot-melt adhesive container (<NUM>), and the heater (<NUM>) and the temperature sensor (<NUM>) are fitted in recesses (<NUM>, <NUM>, respectively) placed in a wall (<NUM>) separating the hot melt adhesive container (<NUM>) from an inner chamber of the gun (<NUM>).