Патент USA US2404736код для вставки
July 23, 1946. L, MARICK . 2,404,736 ELECTRICALLY HEATED COVER Filed Sept. 2, 1942 , /? ‘ "I" JFQ'W/WW M /7 W. ‘ 2Sheets-Sheet 1 ; " +1?’ ..... INVENTOR. 1, a 0/: MAR ICK ATTORNEY , July 23, 1946. 2,404,736 |_. MARICK ELECTRICALLY HEATED COVER Filed Sept. 2, 1942 2 Sheets-Sheet 2_ ‘ -5 ~ l l h v 15. := [I ________1! // INVEN TOR. if“ BY 4011/5 MIR/6K _ ' ATTORNEY ‘ 2,404,736 Patented July 23, 1946 UNITED STATES- ;PATEN T1 OFFI'C ELECTRICALLY 2,404,736 HEATED, - coves; ' ' 51 ‘.; . _ Lo’iiis Marick, Gro‘ssé Pointe Farir'i's,_Mieh-., assign= or to United ‘States Rubber ‘Company,’ New York, N. Y., a corporation of New Jersey - Application September 2, 1942,‘ Serial lira-455,621 1 Claim. \ (o1. 219=19> ' 1 l This invention relates to electrically heated covers for aerial cameras, machine guns vand other mechanical devices that do not work well 2 - as it is desired to neat; f'mayiiave r a " "red to the inflél‘ face thereof one or more electrical‘ eéltiflg units of the desired area. These heatiif' units are preferably ‘formed iiomasheetoi fab ié ‘hav the extremely cold temperatures of high altitudes. Di?iculty has been experienced heretofore ‘in operating aerial cameras- in airplanes ?ying at high altitudes where the temperature maybe as ing a su?‘icient amount of-eléctroeoohduetive i-‘Iib- _ low as -=-60° F. The reason for this is that ‘most aerial cameras are constructed to operate‘ auto element when a differenteelectrical potential is maintained across the sheet. The arrange‘ ent ber wsecured thereto to i‘énd'éi‘tlie fabric aton duetorof' the .pioperiesis'tance to fo‘riii'a heating matically and are provided with gears and slid‘ ing parts that require lubrication. When ex tremely cold the lubricating oil or ‘grease upon these mechanical parts cong'eals' and this is likely to cause such parts to operate slowly and inac - is 's'uohthat each heating element has a large not surface in 'eontactwitha metal "surface of‘th'e gun tole?ectively heat the gun‘, or inlcontact with the other casing to be heated i ‘ , I _ ‘. operating current is preferably supplied to this curately if they operate at all. Furthermore the rated Speed of the unexposed camera ?lm varies with the temperature, the ?lm being more sensitive to light at higher tempera electro-conductive sheet by securing spaced par‘ allel conductive wires; lengthwise" of the sheet. When a heating unit of this type is employed it is unnecessary to use heating wires the fabric tures and has its sensitiveness seriously reduced cover Where they might be injuredgb‘y ‘the flex by extreme cold‘ 20 mg‘ of the cover, and are otherwise objection‘ It is also found that aircraft machine guns ab e. do not operate properly at high altitudes due to the tendency of the intricate parts to stick V s . ’ . The various features .of the‘ présent invention will‘ be more ‘fully understood from the'following description when read in connectioniz‘with‘ the ac; or move sluggishly when extremely coldwan‘d to the formation of ice upon the gun parts when 25 companying vdra'v'vings“illustratinga two‘go‘od prac- a moisture condenses thereupon and then ‘freezes. Likewise aircraft instruments, bomb sights and tical embodiments of the present invention‘ lngthe' drawings: ‘ . . . V other delicate mechanical devices may be adverse Fig.’ ,1 is a perspective view of a machine‘ gun ly affected by extreme cold. s of a type ad‘aptedto be mounted in‘ the wing-'siof Having in mind the foregoing, the present .in_ 30 an airplane, and‘ having the electrically heated vention contemplates electrically heated covers cover of the present invention secured abbut‘t‘he or jackets formed of connected fabricated sec tions shaped to ?t about the casing of ‘the cam era, gun or other mechanical device to be heated, gun casing. ' 17 ‘ _Fig.r3 is an ven'largfe'd sectional view .taken'oii ' the _line'3i—'3' of Fig. 2. V Fig. 4 is a perspective view ofan'aerial vcaiiiéra that is completely‘ enclosed in an electrically heated cover constructedin accordance with‘ the enclosed device warm. the enclosed mechanical device from the cold and con?ne the heat supplied thereto. The cover is constructed to conform closely to the contour of the device upon which it is to be ' shown spread out; and having attached to the sections electrical heating units adapted to be supplied with elec tric energy from the aircraft generator,- batteries or other source of electrical current to keep the The cover is preferably formed of relatively thick heat insulating material, such for example as pads of felt having a protecting sheet of duck fabric secured to each face thereof, to protect ' Fig; 2" is an inside view :of' the cover of 40 presentjnvention; ' ' , Fig.5 is a_ similar viewshowir'ig the cover partly removed so as to disclo‘seth'e aerial camera; and r _Fig'. 6 is an inside view of the cover of, Fig 5 shown spread outi'but with the seams/ingthe' up per_portion of the cover not i?nishfed- and the slide fastener elements not applied; v g 7 It is contemplated» that electrically‘ heated used and to this end is formedrwith sections covers constructed in- aceordance with the pres"; shaped to ?t the different faces of the casing to ent invention ‘may be employed upon various me- ' be heated, and these sections are preferably con 50 chanical devices that are house-din a" casing of nected by hinge-like lines of fold so that they de?nite contour ‘so that: the cover‘ may lbelsrh’alped may be folded snugly about the casing. Slide’fas to conform accurately thereto; The present‘cover tene-rs or other securing means are provided for however has been developed primarily for‘ use removably securing the cover about the casing. upon aerial cameras and gun casingsiin conned; Each cover section, or as many of the sections 55 tion with which it will now be ‘described: : 2,404,736 3 The machine gun of Fig. 1 in itself forms no part of the present invention and may be of well known construction. As shown it comprises the machine gun casing l0 and barrel H. These guns usually are not adjusted while the airplane is in ?ight but are rigidly mounted in the air plane wings so that they may be aimed at the target by directing the airplane itself at the tar 4 which will now be described. These heating ele ments extend over a substantial area of each sec tion and have the construction best shown in Fig. 4 3. Each heating element is preferably formed of a sheet of woven fabric 30 such for example as cotton sheeting having adhesively secured there to or deposited thereupon a ?lm of electro-con ductive rubber to render the-fabric sheet an elec tric conductor of sufficient resistance to produce get. The gun is therefore shown as having the supporting brackets l2 and [3 which are rigidly 10 the desired heating action. The operating cur secured to the wing structure I4. The gun cask " ‘ rent is conveniently supplied to this conductive sheet by folding the longitudinal side edges of the ing II) is provided near its forward end with the sheet around the conductor wires 3| and 32 so slotted opening I5 adapted to receive the belt that these wires extend longitudinally of the fab which supplies the cartridges to the machine gun. ric in direct contact with the longitudinal side Near the rear end of thergun casing 10 there is edges, whereby when these two wires are main provided the rectangular opening I6 for 'an elec tained at a di?erent electrical potential, current tric solenoid unit that operates the gun. will flow across the conductive sheet 30 from one A machine gun is a relatively intricate piece wire to the other to generate heat uniformly of mechanism having numerous cooperating parts that need to be lubricated, and when the 20 throughout the entire conductive sheet. These heating elements may be made as long and as gun is exposed to the extremely cold temperature wide as desired but are preferably rectangular in to which an airplane is subjected when it is ?y shape so that the conductor wires 3| and 32 will ing several miles above the earth, it may oper extend parallel to each other throughout the ate improperly when the_ lubricant is congealed by the cold or fail to operate at all. 25 length of the heating element; It will be’noted that some of the heating elements shown in Fig. The presentinvention seeks to avoid this dif 2 are wider than others, but this condition is ficulty by providing the gun casing with a thick, taken care of by increasing or decreasing the snugly, ?tting cover of heat-insulating material electric resistance of a particular fabric sheet which is adapted to protect the operating parts of the gun from extreme cold, and also to supply 30 by varying the conductive properties of the con ductive rubber applied thereto. , . H > sufficient electrical heat thereto to maintain the It will be noted that the cover shown in Figs. gun operating parts at the desired temperature. 1 and 2 is provided with the openings 33 and The electrically heated cover of the present in 34 near its forward end. This is to clear. the vention can be variously constructed and is pref cartridge belt, not shown, but which enters the erably so made that it can be readily applied to opening [5 above mentioned. -The cover also has the gun casing and removed therefrom, it being the opening 35 to clear the solenoid in the open desirable to remove the casing when the gun is ing IE above mentioned, and it has ,afourth to be serviced before the airplane takes off, but opening 36 shown only in Fig. 2. The heating the cover remains upon the gun while it is in op eration and throughout the airplane ?ight. The 40 elements 36, it will be noted from Fig. 2, are .50 arranged that they clear the openings 35 and cover is therefor provided with such openings 36 and extend over a large area of each of the as may be needed to clear the electric cables lead cover sections 20 to 23. ‘Theconductive sheet or ing thereto and to permit ammunition to be sup heating element 30 is preferably sandwiched be plied tothe gun. tween two sheets of non-conducting rubber to In the construction shown the gun cover is thereby house the conductive sheet 30 between formed primarily of a relatively thick sheet of two protecting non-conductor sheets, The entire insulating material H such as sheet felt sand heating element thus formed is preferably vul .wiched between two woven sheets of fabric l8 canized to or adhesively secured to the inner suchas duck. The cover is preferably construct ed so as to form thick sections having the con tour of the various walls of the gun casing to be covered, and these sections are connected by fabric seams 19 formed by sewing the sheets l8 together at spaced intervals to provide hinge like lines of fold so that the padded cover may be folded snugly about the machine gun casing. fabric sheet l8 of the cover as shown in Fig. 3. Operating current may be supplied to the vari ous heating sheets 33 by the conductor wires 3'! and 38 leading from the airplane batteries or other source of electric energy, and‘ the electri cally heated cover is preferably provided with a thermostat 39 adapted to turn‘ on the current when the temperature drops below a selected point and to turn o? the current when the tem perature rises above this point. The cover is also The cover shown in Figs. 1 and 2 comprises a bottom section 20 which ?ts the bottom or under neath wall of the machine gun casing, two side sections 2| and 22, and a top section 23 that en 60 provided with a condenser 40 to reduce sparking when the thermostat operates. 'It will be noted gages the top wall of the gun casing. The cover that one of the conductor wires such as 31 is'co'n; is further provided with the end sections 24 and nected to one wire 32, of each heating unit 38 25 adapted to enclose the rear end of the gun. It whereas the other conductor wire 38 is connected is also provided with the straps 26, 21, and 23 to the thermostat and condenser just mentioned, near is forward end having the snap fastener 29 and is then connected by the conductor 4| Ito the for securing the cover snugly about the forward end of the gun casing and enlarged portion of the gun barrel. The bottom section 20 of the cover is cut away to a substantial degree as shown to clear the supporting brackets l2 and l3.~ Each of the sections 20 to 23 inclusive is pref erably formed throughout of the two sheets of duck 18 having sandwiched therebetween the thick padding I1, and each of these sections has secured to its inner face thehe'ating element 75 remaining wire 3| of each heating element 30. > The forward end of the cover has a pad 42 of increased thickness adapted to engage the lower face of the gun casing to improve the‘ ?t of'the cover. The cover is shown as provided with the slide fastener 43 and slide fastener elements 43’ extending upwardly along the rear end of ‘the cover and then forward over the top wall of‘ the gun casing as will be apparent from Fig. l. - 2,404,736 5 One example of a good practical electrically conductive cement which may be used to coat the fabric of the heating element 30 is the fol lowing: Parts by weight Rubber _____________________________ __ 100 Conducting carbon black ____________ __ 85 ZnO 15 _______________________________ __ ________________________ __ .75 Accelerator _________________________ __ Antioxidant 2.00 Deodorant __________________________ __ .10 Softener ____________________________ __ l7.00 Vulcanizing agent ___________________ __ Gasoline ___________________________ __ .75 1500 6 vided with such other openingsas are needed to permit access to the portions of the camera that need to be operated while the cover is in place. The cover shown in Figs. 4, 5 and 6 of the draw ings preferably has the same construction in cross section as is shown in Fig. 3, and is provided with electrical heating elements such as shown in Fig. 3. The heating elements in the construction of Figs. 4, 5 and 6 are designated by the numeral 50 and as shown in Fig. 6, three of these heating elements are provided in the cone area, four in the body area and two in the top or magazine area. The cover area for they magazine 44 has the back wall 5|, front wall 52, right side wall 53 and two half side left walls 54. These walls in It will be seen from the foregoing that an elec the finished cover are united by seams which are trically heated cover such as shown in Figs. 1 and only partially formed in the incompleted con 2 provides a simple and practical means for main struction of Fig. 6, and when these seams are taining a machine gun at a desired temperature formed the upper portion of the cover will have even when the airplane in which it is mounted is ?ying at a high altitude where the tempera 20 the box-like shape shown in Figs. 4 and 5. The right side wall 53 is provided with the outwardly .. ture is extremely cold. extending pocket 55 adapted to enclose the Another important use of an electrically heated camera operating motor 56. cover such as contemplated by the present in Operating current is supplied to the electrical . vention is to maintain aerial cameras at the de sired temperature when they are operated at high 25 heating units 50 of the cover by the conductor wires 51 which lead to the thermostat and con altitudes. These cameras are usually constructed denser 58 that ?t within the outwardly project ing pocket 59 of the cover. One of the current tures, and it is found that the extreme cold to supply wires for each heating element is con which they are subjected when the airplane carrying the camera is ?ying at high altitude 80 nected to the wire 60 and the other is connected to the wire 6| leading to the thermostat or one of seriously interferes with the proper operation of the conductor wires 51 as will be apparent from the mechanical part and also reduces the sensi Fig. 6. s to operate automatically to take successive pic tiveness of the unexposed ?lm as above men ' It will be seen from the foregoing that an elec 1 85 trically heated cover such as herein disclosed and I ' There is shown in Figs. 4 and 5 of the draw formed of independently heated sections shaped ings one type of aerial camera which has been to fit the different walls of the gun casing, camera used heretofore and which is adapted to operate or other mechanical device that will not operate automatically to take pictures. This camera may be brie?y described as having the magazine sec 40 properly when very cold, forms a highly practical means of keeping such device warm. ~ tion 44, body 45 and cone section 46. The cone The conductive sheet 30 while above described section 46 is provided with the opposite extend as preferably formed of a fabric sheet treated ing trunnion 41 adapted to support the camera with conductive rubber, may be formed of a con so that it may be manually pointed towards the object to be photographed while the airplane is 45 ductive rubber sheet or conductive plastic sheet alone, and the reference to rubber herein is to be , in ?ight, or the camera may be set so that it construed broadly as covering natural rubber, points in the desired direction with respect to synthetic rubber and rubber-like materials. the airplane before the latter leaves the ground. Having thus described my invention, what I In this latter case its setting need not be changed claim and desire to protect by Letters Patent is: while the airplane is in ?ight. The camera is 50 An electrically heated cover constructed to provided at its lower end with a large lens not enclose a machine gun having an outer casing shown and through which the camera may scan formed with walls disposed at an angle to each the earth below through an opening in the lower other, said cover being formed of fabricated ?ex wall of the airplane. This camera as will be apparent from Figs. 4 55 ible sections of a corresponding size to the respec tive walls of said casing and connected by hinge and 5 is provided with a cover that is constructed like lines of fold of reduced thickness and also to ?t neatly over the entire camera casing and having side openings providing access to the is held in snug engagement therewith by the slide casing, electrically operated non-metallic heating fastener 48 which cooperates with the slide fas tener elements 48' that extend along the top of 60 units secured to the inner face of said sections and disposed so as to clear said openings and. the magazine casing 44 and then vertically down having conductor wires leading thereto, and wardly along the magazine casing, body and cone means for fastening the cover in folded relation to the lower end of the camera as shown. The about the casing, ' cover is provided with the openings 49 through LOUIS MARICK. which the trunnions 41 extend, and may be pro tioned.