US2359712A - Molded door - Google Patents

Description

Oct. 3, 1944. J, 1.. HOWIE, JR

MOLDED noon Filed Aug 9, 1940 2 Sheets-Sheet 2 llllll-llllllm WW/WWW INV ENT OR. J1

ATTORNEY.

Patented Oct. 3, 1944 UNITED STATES PATENT OFFICE MOLDED DOOR John L. Howie, Jr., Decatur, Ill.

Application August 9, 1940, Serial. No. 351,947

10 Claims.

This invention relates to molded doors for'refrigerators, refrigerated shows cases and the like, and has for its principal object the provision of a new and improved door of this kind.

It is a main object of the invention to provide adoor of' this kind that is molded as a single unitary structure.

It is a further object of the invention to provide a moldeddoor that can be glazed with a plurality" of spaced apart panes of glass with the spaces between adjacent panes sealed to reduce heat transfer through the door.

Still another object of the invention lies in the provisionof a molded door having means for receiving nails or screws by which the panes of glass are held in the door so that the established practice of glazing doors of this kind may be followed.

Still another object lies in the provision of a door with outwardIy opening channels in which are formed a plurality of independently closed air pockets which serve to insulate the door against heat transfer.

Still another object of theinvention lies in the provision of a door designed so that it may be molded at low cost.

Further objects of the invention, not specifically mentioned here, will be apparent from the detailed description and claims which follow,

reference being had to the accompanying drawings in which a preferred embodiment of the invention is shown by way of example and in which:

Figure 1 is a plan view of the door with sections broken away to better. show the construction thereof;

Figure 2 is a bottom elevational view of the door;

Figure 3 is an end elevational view of the door;

Figure 4' is a cross-sectional view, taken along the. line 4-4 of Figure 1, looking in the direction of the arrows;

Figure 5 is a cross-sectional view along the line 5-5. of Figure 1, looking in the direction of the" arrows;

Figure 6 is a fragmentary cross-sectional View along the line 6-6 of Figure 1, showing particularly the latchzarrangement; and

Figure 7 is a fragmentarycross-sectional View showing a modified form of baflle;

V Refrigerated show cases, commercial refrigerators and(: the like are-usually provided with sliding doors through which access to the interior may be had. Originally,.these doors were.com-- posed of wood and fitted in wooden tracks in the doorway.

Wood, being more or less porous, was found to be rather unsatisfactory for this purpose, not only because of its tendency to Warp but also because it absorbed odors which tended totaint the food in the refrigerator and even thoughprotected by paintor varnish, the life of the Wood was relatively short due to rotting.

In the prior art of which I am aware, numerous attemptsv to improve upon doors of this kind have been made. In certain instances, wooden door frames have been coated with a coating of rubber or other plastic material but these doors have not been altogether satisfactory. In still other instances, doors have been molded out of synthetic resins, such as Bakelite, but because of the design employed in the door and consequent high cost of fabricating the same, these doors have been too expensive to find general use.

Doors of this kind are usually glazed with several independent panes of glass spaced apart by suitable spacers which. provide dead air spaces between adjacent glasses: so as to insulate the door against heat transfer; Since the air in the room in which the show case or refrigerator is located is at a much higher temperature than the air in the refrigerator and is apt to be rather moist, dew readily collects upon the door frame unless special. arrangements are employed to prevent it. In the prior art, elaborate arrangements for packing the door frame with an insulating material, such as ground cork, have been employed, such arrangements adding furtherto the already high cost of fabricating the door.

In the manufacture of doors. of this kind, it is a well established practice of the glazers to secure the glass panels in the door frame by nails driven through an exposed sealing strip. l/Vhen the door is composed of Bakelite, or other molded material, it is so hard that it is impossible to drive nailsinto it and as a result, threaded openings in the molded door frame into which screws can be driven have come to be employed. Such arrangements increase the cost of. the door still further.

The present invention is directed to the production of a door molded from plastics, such as Bakelite, in such a design that it can be cheaply manufactured; The" door is provided with arrangements whereby it maybe glazed in accordance with the established practice and at low cost.

The doorframe itself is designed so that it may be economically insulatedto prevent the formation of dew upon the face that is exposed to the relatively warm moist air.

The door of the present invention, in its preferred form, consists of a unitary molded frame having a glass receiving panel bounded by flat members which form the webs of channels that open outwardly from the door. A plurality of baffles rise out of each one of the webs into these channels and extend between the opposite faces of the door to divide this channel into a plurality of independents'ections. These baflies also reinforce the frame to make it stiffer and less likely to be sprung out of shape. The adjacent faces of the front and back faces of the door are provided with spaced apart shoulders which between them form grooves opening into the channel, the shoulders adjacent the web being located in accurate alignmentwith the free edges of the baffles. A sealing strip is disposed in the groove so formed and against the free edges of the bafiies so as to form in the channel a plurality of independently closed air pockets which insulate the door frame sufficiently to prevent the formation of dew on the face of the door that is exposed to warm moist air.

The front face of the door overhangs the glass receiving panel to form a flange against which the outermost pane of glass is disposed and this flange may be undercut to receive a sealing strip by which this pane of glass is sealed in the door frame. The webs of the frame contain a plurality of perforations each of which is bounded by a flange formed integrally with the web, and extending into the channelbetween the bafiles. Relatively soft resilient blocks are inserted in these perforations and held therein by frictional engagement by the webs and flanges surrounding the perforations, these blocks being adapted to receive nails or screws by which the strips which hold thepanes of glass in the door are secured to the door.

The end members of the door frame thus formed contain hand-holds which are formed as cavities and by which the door may be grasped to slide the same in the refrigerator case.

Referring now to the'drawings in more detail, the door shown is generally rectangular having a top rail engaging member I, a bottom rail engaging member 2 and end members 3 which extend therebetween, each of these members being a generally channel shaped section. As will be best seen in Figure 4, the bottom member 2 has a front face 2a, a web 4 and a back face 5, the front face 2a extending beyond the web to form a'flange fi-against which the outermost pane of glass I is disposed with'insulating material 8 located in an undercut portion of the flange 6 to seal the space between the glass and frame. The top member I and the end members 3 are constructed in a similar manner and need not be described in further detail herein.

The space between the front and back faces of the door is in the form of a channel into which are projected a plurality of baffles II), which baffles rise out of the web v4 and extend between the faces 2a and 5. These bafiles, being integral with the door, greatly stiffen the same and render it much less likely to be warped or sprung out of shape. At'the ends of the bottom member 2, that is, at the bottom corners of the'door, are generally L-shaped baffles II upon each one of which is mounted a sliding plate I2 by which the door is supported upon a slide rail in the refrigerator doorway. As will be seen in'Figures 2 and 4, the bafiie II contains a groove I3 into which resilient plugs I5 are forced and held by frictional engagement with the flanges I4. The flanges I4 and plugs I5 project into the channel between baffles III but are shorter than the baffles, thatis, the free ends of the flanges I4 are disposed in a plane nearer the web 4 than the free ends of the baffles.

In order to insulate the door, thereby to prevent the formation of dew upon it, it is desirable that the outwardly opening channels be divided into closed air pockets. This can be done in a ..number of ways within the teachings of the invention. In the embodiment shown, the front face 2a and the back face 5 of the door contain shoulders 20 and 2| which between them define grooves 22 opening into the channel as will be best seen in Figure 4. A sealing strip 23 extends across the channel and into the groove 22, this strip being abutted against the free ends of the baffles II] to divide the channel into a plurality of dead air spaces. The ends of the sealing strip 23fit into a similar groove 24 that is located in the bafiies I I at the two corners of the door.

The end members 3 of the door frame are provided with similar baffles Illa-and with a sealing strip 23a which extends from the baffle I I at the :bottom of the door to the corner baffle 25 located at the top of the door ,the strip 230. being in engagement with the baffles Illa to form in the channels at the ends of the door a plurality of independently closed air pockets. Similarly, the top section I is provided with baffles II'Ib which in the embodiment of the invention shown in the drawings are somewhat shorter than the baffles I0 and with a sealing strip 232) which extends from the corner baffles 25 across the channel and in engagement with eachof the baflles' Il'Ib. Since the baffles Illb are shorter than baffies II], sealing strip 23b will be closer to the web of the channel and the groove in the top member will be deeper than the groove in the bottom member, permitting the door to be raised in the usual manner when it is being removed from the doorway of the refrigerator.

With the door frame thus described composed of Bakelite, sealing strips 23 and 23a and 23b are inserted in their respective grooves as soon,

as the door is removed from the molds and before it has had an' opportunity to cool, there being sufficient resiliency in the door-at this time to permit the sealing strips to be sprung to place. As the door cools and the Bakelite shrinks, the sealing strips are more securely bound in place and it has been found that no additional binding is necessary to hold these strips securely in the door frame. If desired a sealing compound such as a phenol glue, may be placed over the joint between the sealing strips and the door, to insure'thatthe joint remains air tight.

As will be seen in Figures 4 and 5, the outermost glass panel 1 is engaged on its back face by spacing strips 38 whichabut against the webs 4 of the door frame and against which a' second glass panel 3I is abutted. The panel 3| in turn is engaged by other spacing strips 32 which 'in turn are engaged by a third glass panel 33. A larger sealing strip 34 is fitted in the door against the w'eb- 4 and against the glass 33, being secured in place by nails 35 which are driveninto the resilient plugs 15., If desired, screws may be used in lieu of the nails 35, the plugs l5..preferabl-y being rubber into which either nails. or screws may be easily driven. Strips 3.0,. 32 and 34 are. preferably wooden strips, although, if desired, other materials may be used. within the teachings of the invention.

As will be seen best in Figure 6, the baflie 25, located at each junction. of the top member I and end member 3 of the door, isstepped at. 40 and. provided with EJ131201]; 4!, the step 40: and latch engaging the guide rail in the refrigerator case to support the door therein. Latch 4| may conveniently consist of a. block of mold-edBakelite, generally rectangular in shape, and provided with aperforation into. which a, guide rod'42 and a spring 43' are extended, the guide rod:pass ing. through a, perforation in an auxiliary baffle 44 against which the spring 43 abuts to urge the latch 4| upwardly into the. position it .is shown in Figures 1 and 6. In order to retract the latch to permit. removing the door from therefrigerator, abutton 48 is secured. to the latch and extended: through a slot M in the sealing strip 23a; so as. to be available at the end of the door. By moving the button downwardly, the latch may be. withdrawn fromthe guide rail and the door thus freed for removal in the usual manner.

As shown in Figure l, the two ends of the top member I of the door are symmetrical in that each is provided with bafile 25. that is arranged to receive a, latch- If desired, latches may be provided. on. both ends of the door although more frequently only one latch will be used which latch may be located at either end of the door as desired.

In Figure 7, I have shown a modified form of baifie which rises out of the web 53 and is thicker than the bafile it heretofore described to accom mo'date a groove 5i that is located at the free ends of the baffle 52'. The bafile extends between the front and back faces of the door and a resilient packingmeans, such as soft rubber 53, may be inserted in the groove 5! so that when the sealing strip 5 3 is set in place, the pockets defined by the baffle will be defin tely hermetically sealed to secure better heat insulating properties.

The pockets formed between the front and back faces of the door and the baffles and closed by the sealing strips have heretofore beenre-- ferred to as dead air spaces and ordinarily the insulation afforded by this arrangement is sufficient. In certain instances. however, particu larly when temperature differences between inside and outside of refrigerator are great it may be advantageous to fill these spaces with a suitable insulating material, such as, rock wool, glass fiber or granulated cork or some other similar material, which material will, of course, be put in the pocket before the sealing strip is sprung into place. Under such conditions the joint between the sealing strips and front and back faces of the door may be coated with a sealing compound, if desired, although this will not ordinarily be necessary.

From the foregoing, it will be apparent to one skilled in the art, that the door of my invention is possessed of many advantages. When molded from Bakelite, as a unitary structure, it is hard non-porous and is not affected by heat or climatic changes and consequently will not readily warp out of shape. Channels in the door are divided into dead air spaces and the formation of dew is thereby eliminated. The plurality of panes of glass may be used and fixed in the door in-..the manner. now'established. as standard. practice, in the glazing of. doors of this type- When composed of Bakelite, the doors. present. a finished. smooth surface formed by molding, and. no finishing. operations are necessary. The material is hard and is not easily scratched. .Although Bakelite. is preferably, employed in the construction of the door of my invention, other plastics may be used, as'will be apparent to one skilled in the art. and changes in design and construction may also be made within. the. teachings. of. the invention.

Having thus complied. with. the statutes, and shown and described a. preferred embodiment of my invention, what I consider new and desire to have. protected by Letters. Patent is pointed out in the appended claims.

What is claimed. is:

l. A rectangular door composed of a hard set molded material, each side of which consists of a channel composed of a web and flanges rising therefrom, baflies extending across saidchannel, and a strip squeezed between said flanges and engaging said baffles to divide the same into a plurality of independent air pockets.

2; A display case door comprising, a rectangular frame, parallel flanges extending around said frame and outwardly therefrom, baffles extending between said flanges and outwardly from said frame, a pair of spaced apart shoulders disposed in each of said parallel flanges, one of said shoulders coinciding with a plane through the free ends of' the baffles, and a sealing strip engaging said shoulders and bafiies to close off a plurality of independent air pockets between said flanges.

3. A one piece door comprising, integral top, bottom, and end members each of generally U- shape cross section and disposed with webs of the members innermost'to form a hollow rectangle with a channel opening outwardly therefrom, integrallips projecting inwardly of said hollow rec'- tangle on one face of said door to form a flange around said rectangle, transparent panel means fitted within said webs and against said flange, there being a plurality of flanged perforations in said webs, a resilient block disposed in each of saidperforations, sealing means for holding said panel means in said door, and means projecting through said sealing means and into said resilient blocks for holding said sealing means and transparent panel means in said door.

4. As an article of manufacture, a one piece door for refrigerators and the like comprising, integral top, bottom and end sections forming a hollow rectangle having a channel opening outwardly from each section, a flange on one side of said door extending inwardly from each section in the plane of one of the faces of the section, transparent panel means in said door abutting against said flange, means securing said panel means in the door, baffles projecting into said channel and extending frome one face of the door to the other, means engaging said baffles and the walls defining said channels to seal a plurality of independent air pockets in the channel, means projecting into the channel in the bottom section of the door for supporting the door in a frame, andlatoh means projecting in the channel in the top section of the door for holding the door in the frame.

5. As an article of manufacture, a door for refrigerators and the like comprising, front and back face members each shaped as a hollow rectangle and joined by a perforated web disposed in juxtaposition to the inner margins of said members, one of said members extending inwardly of said web to form a guide for transparent panel means that fit within the rectangle formed by said webs, means for holding said transparent panel means in said door, said holding means being secured by means projected into said perforations in said web, baffles rising out of said web and extending between said members in the channel between the members, there being grooves in said members opening into said channel in the planes of the free ends of said bafiies, and sealing strips fixed in said grooves and against said baflles to divide said channel into a plurality of independent closed air pockets.

6. As an article of manufacture, a door for refrigerators, and the like comprising, a rectangular frame composed of integral top, bottom, and end webs, an integral flange extending from one edge of said webs at right angles thereto to form one face of said frame, an integral flange extending from the other edges of said webs outwardly therefrom at right angles to the webs to form a second face of said frame which face is disposed parallel to said first face, said flanges bounding a channel that extends around said frame and opens outwardly therefrom, said one face of said frame extending beyond said webs inwardly of the frame to form a guide flange, a lip extending from the free edges of said guide flanges toward the second face of said frame and parallel to said webs, said lips and webs defining a second channel extending around the frame, sealing means disposed in said second channel, glass panel means fitted between said webs and against said sealing means, said glass panel means comprising, a plurality of independent panes of glass and means for spacing the same apart, means for securing said glass panel means in said frame, and means dividing said outwardly opening channel into a plurality of independent closed air pockets.

7. As an article of manufacture, a molded rectangular door, each side of which is of channel cross section with the webs of the channels disposed inwardly of the door and the flanges thereof extending outwardly from the Webs, a pair of shoulders on each of said flanges, said shoulders between them forming a groove opening into the channel, a sealing strip extending across each channel and into said grooves to close the channels, and bafile means extending from the web to the sealing strip and between the flanges of each channel to divide that channel into a plurality of closed pockets. 7

8. As an article of manufacture, a molded rectangular door, each side of which is of channel cross section with the webs of the channels disposed inwardly of the door and the flanges thereof extending outwardly from the webs, baflie means rising out of said webs and extending across said channels to and joined with said flanges, there being grooves in said baffle means, resilient sealing means in said grooves, a sealing strip extending between the flanges on each side of said door and engaging said resilient sealing means to close off a plurality of air pockets in each of said channels, and means in said flanges engaging said sealing strips to hold the same in place in said channel.

9. As an article of manufacture, a molded rectangular door, each side of which is a channel cross section with the web of the channels disposed inwardly of the door and the flanges thereof extending outwardly from the webs, the flanges on one side of said door extending inwardly of the web to form a shoulder, panel means in said door abutted against said webs and against said shoulder, there being perforations in said web, holding means for said panel means secured thereagainst by means projecting into said perforations in said webs, a sealing strip extending between said flanges on each side of said door to close off said channel, baffle means dividing each of said channels into a plurality of independent air pockets, and sealing means disposed in the perforations in said webs and around the projections extending therein to seal said pockets.

10. As an article of manufacture, a door for refrigerators and the like, comprising front and back face members shaped as hollow rectangles and joined by perforated webs disposed in juxtaposition to the inner margins of said face members, one of said members extending inwardly of said web to form a guide for panel means that fit within the rectangle formed by said webs, holding means engaging said panel means and web, means projecting through said holding means and into said perforations in said webs for securing the holding means and panel means in said door, baffles rising out of said web and extending between said face member in the channel therebetween and means for closing and sealing said channel to form closed pockets within said door.

JOHN L. I-IOWIE, JR.

Images