Abstract:
A simple, low-cost, low-maintenance device to be added or built in to a fireplace, which, by convective and radiative means, increases the amount of heat transferred to living areas, is architecturally unobstrusive in design and silent in function.

Description:
BACKGROUND OF THE INVENTION 
     There are devices presently available which use water or other fluids to transfer heat from the fireplace interior to living areas, but these increase greatly the maintenance requirements of the fireplace. Some devices use multiple panels which require hinges, grooved frames, chains, and other unsightly attachments which clutter the appearance of the fireplace interior and also create maintenance problems. Some devices may rely on exotic, highly polished materials for reflection of heat, creating the possibility of constant cleaning being necessary for proper function, or expensive replacement in case of damage. Prior art provides many examples of fireplace devices, but they seem to be expensive, unsightly, complicated in design or hard to upkeep, as evidenced by the fact that none has been generally accepted as an industry-wide &#34;standard&#34; in the fireplace industry. The huge number of fireplaces already present in homes, apartments, etc. has created a need for a low-cost, low-maintenance device which increases fireplace heat production, does not detract from the esthetic appeal of an open fire, and is easily installed. The fireplace heat efficiency device presented in this petition for your consideration meets these needs. 
     SUMMARY OF THE INVENTION 
     This fireplace heat efficiency device consists of a vertical reflector component, a horizontal component, a transition area between the vertical and horizontal components, a shield component and legs or attachment points. Legs may be designed to set on or attach to the firebox floor or fuel grate. Legs or spacers may be used as attachment points for shield component. Shield component functions to provide a passageway of substantially unobstructed space in front of the vertical component to allow convective flow of air/wood gas mixture to flow upward to the horizontal component. Legs or attachment points may be adjustable to provide for different firebox opening heights, the object being to elevate the horizontal component as high as possible so that it is not easily noticed once installed. The device may also be built in to new construction of fireplaces, using the fireplace wall as the vertical reflector component. The simple construction of this device allows use of high quality materials to be utilized at low cost. The inventor paid less the $20.00 at a local sheet metal shop for enough stainless steel to build a model during testing. Use of this type of material provides maintenance-free operation for long periods of time. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the fireplace heat efficiency device. 
     FIG. 2 is a cross section view of the preferred embodiment of the invention. 
     FIG. 3 is a cross section view of the invention illustrating attachment to wall of fireplace. 
     FIG. 4 shows invention attached to fuel grate. 
     FIG. 5 illustrates the device built in to a fireplace. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows the fireplace heat efficiency device in a perspective view with no support or attachment means. 
     FIG. 2 shows the preferred embodiment of the device installed in a fireplace 5a,5b, and 5c; having a firebox floor 5a, a rear wall 5b, an upper surface 5c, a fuel grate 10, a heat source 11, a chimney 12, an opening 17 with an upper boundary 5d. The invention comprises a substantially horizontal surface 1, positioned at the approximate height of the lower edge of the upper boundary 5d, a substantially vertical surface paralleling the rear wall 5b or touching it if possible, a shield 3 attached to the substantially vertical surface 2 and parallel to the vertical surface 2. This configuration forms a passageway for a convective flow of air and wood gases 4 upwardly to the horizontal surface 1. This convective flow ignites and produces additional useful heat. The horizontal surface 1 deflects the convective flow of hot air and burning wood gases away from the chimney 12 and onto the upper surface 5c, thereby raising the temperature of the upper surface 5c, and causing additional heat 6 to be radiated from this surface 5c. Horizontal surface 1 also radiates heat 7a through fireplace opening 17. The vertical surface 2 radiates additional heat 7b; shield 3, which is directly exposed to heat source 11, also radiates heat 7c. In the case of pre-fabricated steel fireplaces which have an air chamber 9 above the upper surface 5c, this air chamber receives heat from the horizontal surface 1, thus increasing the heat 8 transferred outside the fireplace via this chamber 9. The device is supported in FIG. 1 by legs 13 attached to device at one end of the legs, and resting on fireplace floor 5a on the other end of the legs. Two such legs have been sufficient for each device built thus far, but extra legs could be provided if needed. 
     FIG. 3 shows the invention attached to the fireplace wall 5b by attachments 14a and 14b. Screws are shown for illustration, but other means of attachment could certainly be provided. 
     FIG. 4 shows the device attached to the fuel grate 10 by attachments 15a and 15b. Nut and bolt attachment is shown, but other means of attachment could work as well. 
     FIG. 5 is an illustration of the device as an integral part of a fireplace, whereby the fireplace rear wall 5b is built of an appropriate type of material, such as stainless steel, and serves as rear wall 5b and vertical surface 2, providing the same functions as rear wall 5b and vertical surface 2 in FIG. 1. Horizontal surface 1 attaches to vertical surface 5b, using brackets 16 in this illustration; however other means of attachments could be used. The shield 3 is attached to rear wall 5b, as in FIG. 1, in such a manner as to provide a passageway for hot air and burning wood gases to rise upwardly.