US3873029A

US3873029A - Adaptor for flameless heat tools

Info

Publication number: US3873029A
Application number: US414846A
Authority: US
Inventors: Michael F Mihaly
Original assignee: Amerace Corp
Current assignee: Harvard Industries Inc
Priority date: 1973-11-12
Filing date: 1973-11-12
Publication date: 1975-03-25
Anticipated expiration: 1992-03-25
Also published as: FR2250623A1; FR2250623B3; CA1042956A; GB1489228A; DE2453656A1

Abstract

An adaptor is provided comprising a housing defining an interior chamber and being adapted for detachable mounting to the exit nozzle of a flameless heat tool. Supported within the housing interior chamber is a baffle member for establishing an annular shaped heat pattern with respect to the heated fluid exiting from the tool nozzle and the housing interior chamber. The baffle includes means axially extending from the housing interior chamber and beyond the housing, which means are adapted to extend into a work surface opening whereby the annular shaped pattern of heat exiting from the adaptor housing is directed against an annular portion of the work surface surrounding the opening and heat is excluded from the opening.

Description

[ Mar. 25, 1975 ADAPTOR FOR FLAMELESS HEAT TOOLS [75] Inventor: Michael F. Mihaly, Madison, NJ.

[73] Assignee: Amerace Corporation, New York,

[22] Filed: Nov. 12,1973 [21] App]. No.: 414,846

[52] U.S Cl 239/518, 239/135, 219/368,

. 219/373 [51] Int. Cl B05b 1/26 [58] Field of Search 219/368, 370, 373;

[56] References Cited V UNITED STATES PATENTS 428,234 5/1890 Speirs 239/515 1,933,428 10/1933 Harry 239/515 2,114,494 4/1938 Hummel et a1. 219/370 X 2,140,517 12/1938 Dawson 239/514 X 3,371,188 2/1968 Henes et a1. 156/497 X 2/1971 Fuellemann 219/373 Primary Examiner-Lloyd L. King Assistant Examiner.1ohn .1. Love Attorney, Agent, or FirmR. A. Craig; S. Michael Bender, Esq.; Martin Sachs, Esq.

[57] ABSTRACT pattern with respect to the heated fluid exiting from the tool nozzle and the housing interior chamber. The

baffle includes means axially extending from the housing interior chamber and beyond the housing, which means are adapted to extend into a work surface opening whereby the annular shaped pattern of heat exiting from the adaptor housing is directed against an annular portion of the work surface surrounding the opening and heat is excluded from the opening.

17 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION The present invention relates to an adaptor for mounting on the exit nozzle of a flameless heat tool, which adaptor permits the tool to generate an annular shaped heat pattern. Such adaptors are especially useful in connection with installation tools for applying heat-melt fasteners to a laminated panel or similar object.

We are presently aware of several types of installation tools that have been developed for use in installing heat-melt fasteners. Such tools are adapted to generate the heat necessary for melting the adhesive material associated with the fastener thereby enabling the fastener to be adhesively affixed to an object or article. One type of tool converts electrical energy into heat energy and applies the heat energy to the fastener flange by direct contact therewith (conduction) similar to the manner in which a soldering gun is conventionally employed, for example, except that the tip temperature is precisely controlled. Variations in the contact pressure and/or contact temperature may result in an insufficient amount of heat energy being transferred to the fastener flange for a proper melting of the adhesive washer usually disposed between the fastener flange and the surface of the article to which it is to be affixed. Thus, if excessive heat is applied to the panel, it may scorch the panel or adversely affect the panel-to-core laminate bonding.

Another typeof installation tool utilizes high frequency induction heating. The high frequency induction heating tool provides rapid high temperature heating, which can affect the panel or fastener finish. the efficiency and effectiveness of the tool depends on the positioning of the heating coil. These tools are generally large in size, unportable and expensive to manufacture because of the large amounts of energy required for operation.

Still another type of installation tool utilizes radiant heat generally obtained from an iodine quartz lamp with a special filter. The filter functions to screen out the visible light while permitting theinfra-red energy to reach the fastener. This type of tool is small, light in weight, and relatively inexpensive to manufacture. However, the current infra-red radiant heat installation tools typically require a to 18 second heating cycle, which is generally a longer time than preferred. Consequently, there still exists a need for improving the techniques for installing heat-melt fasteners.

SUMMARY OF THE INVENTION The preferred embodiment of the present invention satisfies the foregoing need by providing a relatively inexpensive adaptor which may be used in cooperation with a conventional, portable, inexpensive, flameless heat tool to significantly render more efficient-the installation of fasteners of the heat-melt type.

Thus, one object of the present invention is to provide an adaptor for a flameless heat tool which is effective to reduce the installation time of heat-melt fasteners.

Another object of the present invention is to provide an adaptor for a flameless heat tool capable of reducing the installation time of heat-melt fasteners without damaging the finish on the fastener or of the panel to which the fastener is to be affixed.

A further object of the present invention is to convert a compressed air flameless heat tool into an installation heat tool for heal-melt fasteners.

Another object of the present invention is to provide a relatively inexpensive adaptor for a flameless heat tool capable of providing an essentially annular shaped heat pattern.

A still further object of the present invention is to provide an installation tool for heat-melt fasteners that distributes the heat evenly over the flange of the fastener while protecting the central threaded area from being damaged by heat or adhesive.

An adaptor for use with a heat tool having a nozzle through which heated fluid exits, according to the prin' ciples of the present invention, comprises housing means for defining an interior chamber, the housing I means having first and second open ends including a portion adjacent the first end thereof adapted for detachable mounting to the exit nozzle, baffle means disposed in the interior chamber for defining therein an annular shaped orifice communicating with the exit nozzle through the first end of the housing means and for guiding the heated fluid exiting from the nozzle through the annular shaped orifice and the housing means second end, the baffle means including means axially extending beyond the housing means second end for centrally locating the annular shaped orifice relative to a work surface having an opening therein, the axially extending means being adapted to be received within the opening to exclude the heated fluid therefrom, and means for supporting the baffle means relative to the housing means.

BRIEF DESCRIPTION OF THE DRAWING position guiding a heated fluid onto the flange of a heat-melt fastener;

FIG. 3 is a bottom view of an alternative embodiment of the adaptor of the present invention; and

FIG. 4 is a plan view of the heat pattern generated by the adaptor of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The term heat-melt fastener as referred to herein generally refers to the type of fastener. Iocknut. or the like that is adapted to be mounted on a panel or similar such object which may be either metallic or nonmetallic, or of the sheet material or sandwich type. The fastener is made of metal and has associated therewith an adhesive material which may be pre-applied to the rear or panel side of the fastener flange or may include a separate adhesive washer which cooperates with the fastener and is placed between the fastener flange and the panel. Common characteristics of these devices are that they generally require pressure to hold them to the panel during installation and that heat is required to Y the fastener and panel. A typical heat-melt fastener is 7' source of compressed air 14 is preferably modified in a known manner to include an air pressure gage and a pressure adjusting regulator 22. The output air temperature thus may be adjusted by cooperatively utilizing the'gage 20 and regulator 22 to adjust the pressure of the air or air flow into the flexible hose 24 clamped by clamp 26 to the handle input duct 28 usually found at or adjacent to the rear of the handle 30 of the heat tool 12.

The flameless heat tool, 12 is conventional and the details thereof form no part of the present invention. A commercially available heat-toolof the type generally described above is the Model FHT-67-l, manufactured by the Master Appliance Corporation of Racine, Wisconsin which includes a conventional resistance heater element (not shown) axially located beneath the heat shield 32 of the tool 12. The resistance heater element is energized by a switch 34, which is connected via an electrical line cord .36 and plug 38, to a conventional source of electrical power such as 110 volts at 60 Hz (not shown). the resistance heater element may be purchased with different heat or wattage ratings. When the resistance heater element is energized the quantity and pressure of air communicating with the element determines the output nozzle temperature. The compressed air flameless heat gun 12, described above, provides a concentrated amount of heat energy at the exit nozzle but does not provide efficient heat distribution so that itcannot be used efficiently by itself without the adaptor l6as an installation tool for heat-melt fasteners.

By affixing adaptor l6.to the exit nozzle 18 of the heat gun 12 the normal output air pattern from the gun will be converted to an essentially annular shaped pattern as shown in FIG. '4, and indicated generally by reference numeral 40. This annular heat pattern 40 provides a substantially evenly distributed ring of heat 42 on the upper surface of flange 44 of a fastener 46 which is shown in cross-section in FIG. 2, it being noted however, that the heat pattern 42 may be slightly discontinuous because of the shadow cast by the mounting rod 74. Heat is excluded from the open portion of the fastener because it is shielded therefrom by the lower portion 94 of the baffle 50 as shown in cross-section in FIG 2 which axially extends into the central opening 110 in the fastener 46as will be more fully explained below.

Thus, as shown in the enlarged cross-sectional view of FIG. 2, the adaptor 16 is detachably affixed to the .exit nozzle 18 of the gun 12 and is disposed in cooperative engagement with a heat-melt fastener 46. The fastener 46 includes an axially extending hollow cylindrical portion 45, the interiorvsurface of which may be threaded as shown. The axially extending cylindrical portion 45 is inserted into a suitably sized opening 60 pre-drilled into panel 52 which may be of the sandwich 4 panel type having, for example, fiberglass cover sheets affixed to a hexagonal cell honeycomb core.

An annular shaped adhesive washer 54 is emplaced between the underside of the fastener flange 44 and the upper surface 56 of the panel 52. The central portion of the adhesive ,washer preferably is cut to provide tabs 58 that are permitted to position themselves along the external surface 59 of the internally threaded cylindrical portion 45 of the fastener 46. The heat-melt fastener 46 preferably is fabricated'from lightweight thincarbon steel sheet stock and is heat treated to provide optimum strength and locking torque capabilities.

Cadium plating is employed to provide corrosion resistance. The adhesive wafer 54 may be fabricated of a nylon polyamide material securely prefitted to the external surface 59 of the threaded cylindrical portion 45 of fastener 46.

The adaptor 16, preferably is provided with a hollow funnel shaped housing 62 which has an axially extending portion 64 adapted for detachable mounting to the exit nozzle 18, via set screws 66 inserted within threaded holes 68 provided in the axially extending portion 64 of housing 62. Although the lower portion of housing 62 is shown to be conically shaped in the preferred embodiment, this is not critical. It is impor tant only that the inner walls of the housing 62 be so shaped as to form in conjunction with baffle 50 an annular shaped orifice or aperture 70 communicating with the heated fluid 72 exiting from nozzle 18 of heat gun 12. Thus, the heated fluid, e.g., air, 72 flows through the exit nozzle 18, the interior chamber defined by housing 62, the annular shaped orifice 70 in the interior chamber and finally exits through the open bottom end of. housing 62.

Supported within the housing 62 is a conically or similarly shaped baffle 50, which deflects the heated fluid or air emanating from the exit nozzle 18 to form the annular pattern 40 (FIG. 4), described earlier. Baffle 50 in the preferred embodiment of the invention, is retained within the housing 62 by a stainless steel rod 74 adapted to be interference fitted within a through hole 78 provided in the baffle 50 and retained in diametrically

opposed holes

80 and 82 provided in or adjacent the lower portion of housing 62. The rod'74 is preferably retained in position by

C washers

84 and 86 coacting with

grooves

88 and 90 provided in the rod 74 and is designed to withstand a load pressure of 25 pounds which may be applied to it during installation of a fastener. In order to prevent rotation of baffle 50 relative to housing 62, rod 74 and through hole 78 may have a non-circular cross-section. The baffle or heat deflector 50 may be considered to comprise an upper portion 92 and a lower portion 94 and is preferably of unitary construction. The-upper, portion 92 of the deflector 50 is preferably'conically shaped having its side walls and 102 generally parallel to the interior-or

inside walls

104 and 106 of the housing 62 to provide annular orifree 70 communicating with the nozzle 18 through the open upper end of housing 62. The lower portion 94 of deflector 50 is preferably shaped as an inverted truncated cone, but is not to be so limited. The lower portion 94 is preferably positioned to axially extend beinterior surface of opening 110 from the heated fluid 72, as well as position and maintain the housing 62 at a sufficient distance spaced above the upper surface of flange. 44. This arrangement allows heated fluid or air 72 to freely flow through the annular orifice 70 and be directed against the upper surface of flange 44 of fastener 46. In addition, it will be noted that the sloping

walls

112 and 114 permit the lower portion 94 of baffle 50 to seal different size openings. Since the flow of heated fluid is prevented from entering the threaded opening or aperture 110 of fastener 46 it cannot enter the core of the sandwich panel 52, thereby preventing the core material from being damaged from-the exposure to heat. Exclusion of heated air from opening 110 also prevents heat damage to the threaded surfaces therein.

Turning now to FIG. 3, there is shown a bottom view of an alternative embodiment of the adaptor 16 which utilizes multiple rod sections 120 to support the baffle 122 within the housing 124. The rod sections may be press fitted or threaded into the baffle 122 in a substantially equally angularly spaced relation about the baffle and inserted within corresponding holes 126 provided in housing 124. Alternatively, the baffle 122 may be removably retained within the housing 124 to permit rapid changing of the baffle. In all other respects the alternative embodiment of FIG. 3 is the same as that of FIGS. 1, 2, and 4. v

In operation, the heat-melt fastener 46 is installed in the panel 52 by drilling the recommended size hole 60 in the panel 52 to receive the fastener. The adhesive washer 54 is then fitted relative to the cylindrical portion 45 of the fastener 46, as shown in FIG. 2. Next, the cylindrical portion 45 of the fastener 46 is inserted into the hole 60. The flange 44 need not be seated against the panel 52 since the heat and pressure of the tool will automatically position the fastener 46 properly. The lower portion 94 of the baffle 50 is inserted into the threaded opening 110 of the fastener 46 with a pressure generally less than 25 pounds. The pressure regulator 22 is adjusted to the proper pressure setting, required by the heating element used, to obtain the manufacturers recommended temperature for melting the adhesive used with the fastener. Once the air flow/pressure has been adjusted, switch 34 is placed in the on position energizing the heater element, thus permitting the air to be heated to the proper temperature as it passes thereover. The adhesive 54 held between the panel 52 and the flange 44, will melt in 5 to seconds since the heated air 72 is evenly distributed and confined to an annular pattern substantially coextensive to the upper surface of the fastener flange 44. Switch 34 is then turned off, and tool removed from its engagement with the fastener 46.

It is to be noted that the switch 34 may be made to control the energization of the heater element as well as to control an electrically activated valve to permit the air to flow, once the pressure from the air source has been preset. Also, a timing mechanism may be used to automatically shut-off the heater element and air flow after a preset time interval.

It is also to be noted that although the baffle 50 and rod 74 is shown to be made of multiple elements, it is within the scope of this invention to fabricate it as a unitary structure. I

From the foregoing, it should now be apparent that the present invention provides a inexpensive adaptor means.

which may be affixed to the exit nozzle of conventional flameless heat guns to convert them into efficient, portable, inexpensive installation tools for use in installing heat-melt fasteners.

Having thus set forth the nature of the invention,

what is claimed is:

1. An adaptor for use with a heat tool having a nozzle through which heated fluid exits, comprising:

. a. housing means for defining an interior chamber, said housing means having first and second open ends including a portion adjacent said first end thereof adapted for detachable mounting to said exit nozzle;

b. baffle means disposed in said interior chamber for defining therein an orifice communicating with said exit nozzle through said first end of said housing means and for guiding said heated fluid exiting from said nozzle through said orifice and said housing means second end, said baffle means including means extending beyond said housing means second end for locating said orifice relative to an opening provided in a work surface, said extending means being adapted to be received within said opening to exclude said heated fluid therefrom; and

0. means for supporting said baffle means relative to said housing means.

2. An adaptor according to claim 1 wherein said orifice is generally annular shaped.

3. An adaptor according to claim 1 wherein said extending means axially extends from said housing 4. An adaptor according to claim 1 wherein said means for supporting said baffle means includes rod means affixed to said housing means and being adapted to cooperate with said baffle means for axially positioning and retaining said baffle means within said interior chamber.

5. An adaptor according to claim 1 wherein said supporting means is removably retained within said housing means.

6. An adaptor according to claim 1 wherein said baffle and supporting means are a unitary construction.

7. An adaptor according to claim 1 wherein said housing means second end is displaced from said work surface when said extending means is received within said opening.

8. An adaptor according to claim 1 wherein said housing means is funnel shaped and said first end portion is annular shaped.

9. An adaptor according to claim 1 wherein said heated fluid is air.

10. An adaptor for a flameless heat tool having a nozzle through which heated fluid exits. said adaptor being suitable for applying heat to a workpiece having an opening therein, comprising:

a. a funnel shaped housing having a relatively wide opening at one end and a relatively narrow opening at its other end;

b. means for detachably mounting said other end to the exit nozzle of said flameless heat tool;

c. a heat deflector having an upper and lower portion, said upper portion having side walls generally parallel to the inside walls of said housing to provide means for enabling a generally annular shaped pattern of heated fluid to exit from said one end of said housing, said lower portion axially extending beyond said one end of said housing to define means adapted to extend into said opening in said workpiece to positively locate said housing relative to said opening and maintain said housing one end at a distance spaced above said workpiece while preventing said heated fluid from entering said opening in said workpiece; and d. means for axially positioning and retaining said heat deflector within said funnel shaped housing. 11. An adaptor according to claim 10 wherein said other end includes a portion having threaded holes therein and said mounting means includes a set-screw threadedly engaged within each of said holes.

12. An adaptor according to claim 10 wherein said heat deflector is provided with a through hole proximate the junction of said upper and lower portions and.

said last-mentioned means includes a mounting rod affixed to said housing and adapted to cooperate with said through hole for axially positioning and retaining 15. An adaptor according to claim 14 wherein said lower portion extending from said housing has inwardly sloping sidewall surfaces.

16. An adaptor according to claim 10 wherein said means foraxially positioning and retaining said heat deflector includes a plurality of rods substantially equiangularly disposed about said heat deflector and affixed between said housing and said heat deflector.

17. The adaptor according to claim 10 wherein said workpiece comprises a sandwich panel fastener, said fastener including a flanged metal locknut having a centrally threaded portion defining said opening and an adhesive washer disposed underneath said flange in juxtaposed relation thereto surrounding said centrally threaded portion, said adhesive washer being adapted to affix said flange to a surface in contact with said adhesive washer upon said lower portion of said heat deflector being received within said centrally threaded portion of said locknut and said annularly shaped-pattern of heated fluid being directed onto the upper surface of said flange, said adhesive washer being-responsive to the application of such heat to affix said flange to said surface in contact therewith.-

Claims

1. An adaptor for use with a heat tool having a nozzle through which heated fluid exits, comprising: a. housing means for defining an interior chamber, said housing means having first and second open ends including a portion adjacent said first end thereof adapted for detachable mounting to said exit nozzle; b. baffle means disposed in said interior chamber for defining therein an orifice communicating with said exit nozzle through said first end of said housing means and for guiding said heated fluid exiting from said nozzle through said orifice and said housing means second end, said baffle means including means extending beyond said housing means second end for locating said orifice relative to an opening provided in a work surface, said extending means being adapted to be received within said opening to exclude said heated fluid therefrom; and c. means for supporting said baffle means relative to said housing means.

3. An adaptor according to claim 1 wherein said extending means axially extends from said housinG means.

4. An adaptor according to claim 1 wherein said means for supporting said baffle means includes rod means affixed to said housing means and being adapted to cooperate with said baffle means for axially positioning and retaining said baffle means within said interior chamber.

9. An adaptor according to claim 1 wherein said heated fluid is air.

10. An adaptor for a flameless heat tool having a nozzle through which heated fluid exits, said adaptor being suitable for applying heat to a workpiece having an opening therein, comprising: a. a funnel shaped housing having a relatively wide opening at one end and a relatively narrow opening at its other end; b. means for detachably mounting said other end to the exit nozzle of said flameless heat tool; c. a heat deflector having an upper and lower portion, said upper portion having side walls generally parallel to the inside walls of said housing to provide means for enabling a generally annular shaped pattern of heated fluid to exit from said one end of said housing, said lower portion axially extending beyond said one end of said housing to define means adapted to extend into said opening in said workpiece to positively locate said housing relative to said opening and maintain said housing one end at a distance spaced above said workpiece while preventing said heated fluid from entering said opening in said workpiece; and d. means for axially positioning and retaining said heat deflector within said funnel shaped housing.

11. An adaptor according to claim 10 wherein said other end includes a portion having threaded holes therein and said mounting means includes a set-screw threadedly engaged within each of said holes.

12. An adaptor according to claim 10 wherein said heat deflector is provided with a through hole proximate the junction of said upper and lower portions and said last-mentioned means includes a mounting rod affixed to said housing and adapted to cooperate with said through hole for axially positioning and retaining said deflector within said housing.

13. An adaptor according to claim 10 wherein said heated fluid is air.

14. An adaptor according to claim 10 wherein said heat deflector upper portion is conically shaped and has its apex disposed within said housing.

15. An adaptor according to claim 14 wherein said lower portion extending from said housing has inwardly sloping sidewall surfaces.

16. An adaptor according to claim 10 wherein said means for axially positioning and retaining said heat deflector includes a plurality of rods substantially equiangularly disposed about said heat deflector and affixed between said housing and said heat deflector.

17. The adaptor according to claim 10 wherein said workpiece comprises a sandwich panel fastener, said fastener including a flanged metal locknut having a centrally threaded portion defining said opening and an adhesive washer disposed underneath said flange in juxtaposed relation thereto surrounding said centrally threaded portion, said adhesive washer being adapted to affix said flange to a surface in contact with said adhesive washer upon said lower portion of said heat deflector being received within said centrally threaded portion of said locknut and said annularly shaped pattern of heated fluid being directed onto the upper surface of said flange, said adhesive washer being responsive to the application of such heat to affix said flange to said surface in contact therewith.