Rock channel heat storage

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structure to be heated or cooled. The ducts can be used

ROCK CHANNEL HEAT STORAGE in any desired manner for heat distribution or cold distribution.

BACKGROUND OF THE INVENTION In areas where the water table is not a substantial 1. Field of the Invention 5 factor, the rock filled channels can be used as they are The present invention relates to the storage of heator formed without any additional insulation or other ex cold in substantial quantities over relatively long pe pensive additions, excpet for being covered over after riods of time. they have been filled. Heated or cooled air is circulated 2. Prior Art to the rocks for heat exchange. The sources of heated With the recent emphasis on use of solar heat, in 10 or cooled air may be solar heat collectors, or ambient particular, the problems associated with storing such air heat or cold collectors, or heat from industrial heat for use at a later time have become more appar power plants or other locations where an excess of heat ent. The high cost of construction of storage devices is provided at times.

has minimized the effectiveness and utility of solar Because large amounts of earth are in thermal heat. Likewise, storage of heat from any source as well 15 contact with the rock-filled channels, earth participates as the storage of "cold' or negative heat has been a in the heat storage. In the case of long duration heating problem. In general, large volumes of storage media are or cooling (a number of hours or days or longer), heat storage of the adjacent earth may equal or even greatly absolutely essential, and at the present time the costs of exceed providing storage devices of adequate size has proved the amount of heat stored in the rocks them to be a limiting factor. 20 selves.

In the prior art, the use of solid heat or cold storage Two forms of the invention are shown, providing media has been known. Likewise, in-ground storage, different heat flow patterns. Various configurations of where the ground itself has been used for heat or cold course can be formed without departing from the scope storage is shown in U.S. Pat. No. 3,262,493, where of the invention. The ability to provide the low cost ducts are buried directly into the ground. The undis 25 channels easily constructed with existing excavating turbed earth around the ducts is used for heat or cold equipment, and using the earth which is already present storage. Thus, high cost duct work is provided in the together with low cost rock fill increases the economic ground, which is expensive to install and also to main feasibility of utilizing low cost energy sources for heat tain. A liquid is used for heat exchange, raising the ing or cooling.

costs of construction even further. 30 In the case of a high water table, very difficult digging The use of rock as a storage medium is shown in U.S. or other problem, the heat storage structure may be Pat. No. 2,680,565. A separate chamber inside a room built above or partly above the original grade line so as to form a small hill.

or bin within the home being heated is used for the rock. BRIEF DESCRIPTION OF THE DRAWINGS Other devices utilizing solid material heat storage 35 media are shown in U.S. Pat. Nos. 3,369,541 and FIG. 1 is a part schematic vertical sectional view 3,412,728. These patents are believed to be typical of through a section of earth showing the storage system many others which use stones or sand within chambers made according to the present invention installed adja or bins for heat storage. cent to a building and taken as on line 1-1 in FIG. 2; In some cases, one is concerned that internal circula 40 FIG. 2 is a sectional view taken as on line 2-2 in tion should not happen, such as a case where rocks in FIG. 1;

FIG. 3 is a vertical sectional view of a modified form one end of a channel are hot and are cold in the other end. This is known and a preventative measure is ofFIG. the invention taken as on line 3-3 in FIG. 4; and 4 is a sectional view taken as on line 4-4 in known, of circulating the air vertically, as described in

Solar Energy Thermal Processes by Duffie, J. A., & 45 FG. 3.

Beckman, W. A., John Wiley & Sons, Inc., 1974, p. b DESCRIPTION OF THE PREFERRED 227-228. EMBODIMENTS SUMMARY OF THE INVENTION Referring first to FIG. 1, a heat storage area or bed The present invention relates to the provision of 50 indicated generally at 10 is positioned adjacent the channels dug directly in the ground with existing exca building 11. The building is shown merely for sake of vating equipment and which are filled with rock to convenience, and the storage area 10 may be spaced a provide a heat or cold storage medium in large quanti substantial distance from the building if desired. The ties that will permit the heating or cooling of occupied building wall 12 is shown below the grade line 13 of the structures in times of need. Adequate volume of stor 55 ground.

age material can be provided without exorbitant costs In the construction of the heat storage system, (heat and without providing above ground storage facilities. is used in its broad sense to include negative heat or In its simplest form a trencher used commonly for cold) a plurality of channels as indicated at 14A, 14B, forming drain fields, septic systems, and also for shal and 14C are excavated into the ground in desired loca low sewer work or a commonly available "back hoe' 60 tions, to desired depths and at desired widths. Excava digger is used to dig a number of channels in desired tion equipment used for ditching can dig down to a locations in the ground adjacent to the structure to be depth of 12 feet below the surface of the ground with heated or cooled. The channels are then filled with out any problem. A typical width may be in the range of rock or rock-like material of suitable size and suitable one foot, and the length can be practically any desired connecting ducts are placed in position as desired. 65 length. The channels can be squared off fairly well Additional channels may also be quicky dug if desired. adjacent their side edges, and the bottoms can be These connecting ducts are then piped to the source of formed substantially planar without substantially dis heat or cold, and to the heating or cooling system of the turbing the earth indicated generally at 15 between the

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channels. One such channel has been made and used the building if desired to completely surround the stor with horizontal airflow to store cold in winter for many age channels 14.

months, with results generally as described herein. The trenches 33 and 34 can be filled with other insu If desired, the entire overlying area of the storage lation, and/or water impervious material indicated gen area 10 can be excavated to a suitable depth before the 5 erally at 35, to surround the storage bed. This insula channels are started to provide a space for insulation of tion skirt or enclosure is merely an optional configura the channels if desired or the chanels can be started at tion and in most instances it is not necessary unless the the surface of the ground. Further, excavations at right water table is high or other unusual problems exist. angles to the channels can be made adjacent the ends As shown schematically, a fan indicated at 36 can be of the channels 14A, 14B and 14C for the installation 10 provided in one of the ducts 20 or 21. This fan is for of main supply and return ducts or pipes indicated either sending heated or cooled air into the storage generally at 20 and 21, in FIG. 2, which is a plan sec media. Also, fans may be provided to pass air from the tional view of the storage area. The ducts or pipes can atmosphere to the storage material for heat or cold then be installed in the side channels in a known man storage.

ner and extended into the building 11 if desired. Fur 15 The vertical distributor ducts 22A-22C and 23A-23C ther, as shown in FIG. 2 vertical distributor ducts or are each provided with a plurality of apertures through conduits indicated at 22A, 22B and 22C are installed the walls thereof. These apertures are indicated at 37, adjacent one end of the respective channels 14A-14C, and provide for a discharge of air or other fluid from and vertical distributor ducts or conduits 23A, 23B and 20 either one of the ducts 20 or 21 into the rock storage 23C are installed at the opposite ends of the channels media, and also for exit of fluid from the other of the 14A-14C. The distributor ducts extend for the vertical supply ducts.

depth of the channels and are contiguous to the rocks The ducts 22A-22C and 23A-23C extend vertically filling the channels 14A-14C. The distributor ducts along the ends of the channels 14A, 14B and 14C, 22A-22C are connected through short duct connector respectively, so that fluid in these ducts will be dis sections 24 to the interior of one supply duct or pipe 25 charged along the vertical dimension of the channels 20, and the vertical distributor duct conduits 23A-23C 14A-14C.

are connected through duct connector sections 25 to The ducts 20 and 21 as shown are near the top of the the interior of the conduit or pipe 21. The connections channels 14A-14C, but they could be in the vertical can be made in a manner well known in sheet metal 30 midportions, or near the bottom if desired. Further, the work, or plastic ducts of known configuration also may two ducts 20 and 21 do not have to be on the same be used. level. That is, one may be adjacent the top of the chan After the ducts have been installed as shown, the nel 14A-14C and the other adjacent the bottom of the channels 14A, 14B and 14C, as well as other channels channels if desired.

that might be constructed are filled with discrete parti 35 The fan shown schematically at 36 is merely for illus cles such as rock 25 of suitable size. After filling, the trative purpose. It can be understood that the heat channels 14A, 14B and 14C as shown extend to a level storage media comprising the rocks in the channels slightly above the top of the ducts 20 and 21. When the formed directly into the earth together with the adja channels 14A-14C have been filled with rock suitable cent earth can be used for storing solar heat; for storing covers indicated at 27 can be placed over the tops of 40 heat from air conditioning units; or for storing excess these channels to prevent additional fill or other for heat from power plants in the summer, for example. eign material from getting into the spaces between the The supply ducts can be connected in any desired man rocks in the channels. The loose rock provides a porous ner for either heat storage or cold storage, and the filler for the channels 14A, 14B and 14C which filler removal of cool air or hot air from the storage bed. has a high percentage of interstitial space through 45 It is important to note how heat is exchanged be which air can readily pass. A layer of fill (sand or dirt) tween the earth and the rock filled channel. When heat indicated at 28 can be placed over the covers 27, and is being added rapidly, say for a few hours or less, only above that a layer of insulation such as sawdust, hay, or a few inches of the adjacent earth is significantly other low cost insulation and indicated generally at 30 heated. On the other hand, when heat is added over a can be placed. The depth of this insulation can range 50 long period of time, either continuously or intermit from 3 to 24 inches, depending on the locality and type tently, a considerable thickness of adjacent earth may of use of the heat storage channel. Above this layer, a be heated. When the period of heat addition lasts for layer of polyethelene sheeting (or other water impervi several days or several weeks or longer, all of the earth ous sheet) indicated generally at 31 can be placed to between the channels may be heated significantly and provide a ground water barrier, and sod or other mate 55 store a major portion of the heat, even when the thick rial indicated at 32 can be placed on top of the ness of earth between channels is a gret as 4 to 10 feet polyethelene so that the upper surface of the ground or more. Relatively small channel spacing is appropri resembles or is identical to the lawn or other ground ate when short heat storage duration is important, and surface adjacent the area where the channels 14A relatively great spacing is appropriate when very long through 14C are dug. 60 heat storage duration is involved. The same behavior Once the storage bed has been constructed as shown, exists when heat is being removed. Further, these con the outer periphery can be insulated or protected from siderations apply whether the problem is that of storing water intrusion if desired by digging separate trenches heat or storing cold. Thus, the methods of heat storage indicated generally at 33 and 34, which trenches would discussed here have particularly attractive features meet at the end of the heat storage area (surround the 65 when relatively long term storage and removal are area) and as shown may terminate at the building wall important, say at least a day or a few days, and espe 2. However the separate trenches could also be con cially when as long as several days, several weeks or nected between the first rock storage channel 14A and even several months.

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In spite of this, not a great deal of heat is lost down bottom of each channel 43A-43C extending laterally ward or outward in the long term. This is partly because outwardly from the ducts 44 and 45. Flow passageways of the nature of soil and partly because of the nature of to the rock from the lateral passageways are also long term transient heat conduction. Soil is not a good formed by the spaces between the adjacent blocks 46 heat conductor, nor is it a good insulator. It has a fairly orThe

ducts 44 and 45 are connected to ducts on the good heat capacity. For such materials, well known transient heat conduction theory provides some impor interior of the house, and suitable fans or other devices tant results. Over a period of a few hours heat does not for circulating air through the duct 44 and 45 can be move very far into a layer of earth. Over a period of a provided.

few days or weeks, or even months, heat may move a 10 The channels and the blocks 51 are then covered number of feet into soil but at distances of 10 or 20 feet with suitable covers 52, and a layer of fill 53 can be or more, many months are needed before significant installed above these ducts if desired. Then a layer of temperature changes are felt. For long term use, the insulation material 54 can be provided as well as a type of heat storage described herein behaves as if it polyethelene sheet 55.

were losing heat rapidly downward and to the sides at 15 Sod or other material 56 then can be used for topping first, and then more and more slowly as time goes on, so off the storage bed or area so that it appears the same that after two or three years the heat loss rate is low. as other adjacent areas of the ground. One can view this as a result of the surrounding earth andThe4 isadvantage of the arrangement shown in FIGS. 3 having been slowly brought near the mean temperature that the heat or cold can be caused to remain of the storage system, which suppresses heat loss. Also, 20 stratified. In some storage units using rock or other the distance over which heat must be conducted be media of large volume which permits air circulation comes very great. through the media, a natural convection will be set up. Referring now to FIGS. 3 and 4, a modified form of Adjacent one end of the rock the warmer air will rise, the invention is shown. In the modified form, the same and air will flow along the top of the storage area. A general construction is used, but a different distribution 25 return flow passes down along the opposite side of the system is utilized for circulating air to and from the media and a return cross flow is formed at the bottom. storage material. As shown, a storage area or bed indi This convection induced circulating flow tends to cated generally at 40 is adjacent to a house or building equalize temperatures so that the medium in the enclo 41, which has a wall 42. The storage area or bed is sure will tend to be maintained generally at a substan made up of a plurality of channels 43Aa, 43B and 43C 30 tially equal temperature. Better heat exchange occurs dug directly into the earth, as in the previous form of with a larger temperature differential between the ex the invention. change airflow and the medium, so it is desirable to The channels 43A-43C are connected by an upper have stratified layers, with the hottest material at the conduit or duct 44 and a lower conduit or duct 45 both top, and lower temperatures at the bottom. The form of of which extend transversely to the channels. These 35 the invention shown in FIGS. 3 and 4 permits this desir ducts may be installed by excavating another separate able result to be achieved.

channel at right angles to the channels 43A-43C and Thus, in this form of the invention, the cold air con placing the ducts 44 and 45 in the separate channel. nection, whether cold air is being taken out or provided In constructing the storage system of this form of the to the storage material, is at the bottom and thus duct invention, after the channel 43A43C (and any other 40 45 is the cold air duct. The hot air duct, whether heat additional parallel channels desired) have been is being taken out or going into the storage medium formed, and the cross channel or channels have been channels is at the top and the hot air duct is thus duct dug for installation of the supply and return ducts 44 44.Both of the ducts 44 and 45 can be at the ends of the and 45, the lower duct 45 is placed into position in the midportions of the channels 43 as shown (of course the 45 channels 43, or alternately both large ducts 44 and 45 duct 45 could be at either end of the channels 43 if could be near the surface of the ground and separate ducts used to feed air to the blocks 46 of each channel desired) and a plurality of cinder or concrete blocks or 43 tiles indicated at 46 are laid in the bottom of each of so that cold air that was added to or removed from the channels 43A-43C. The blocks 46 are spaced apart the storage media would be still supplied at the bottom as shown at 47 for air circulation between the blocks. 50 of the cross channels 43A-43C through the blocks 46. As shown, the duct 45 has a plurality of openings 48 Water barriers can be installed around the storage through the wall thereof on opposite sides thereof bed 40 if desired. If ground water is a serious problem, aligning with the channels 43A-43B so that the open the entire bed location can be excavated to form a large ings 48 open to the interior passageways of the respec hole and then the hole lined with polyethylene or suit tive blocks 46 on opposite sides of the duct 45. The 55 able waterproof material and refilled in the form interior passageways of the blocks 46 and the aligning shown, with the cross channels 43A-43C holding the opening 48 can be seen in FIG. 3. porous rock being separated by filled layers of earth. The channels 43A43C are then filled with rock or in addition, in other situations where water intrusion suitable size and the cross channel cut for installation is a serious problem, for example because of a high of the duct 45 can be filled with earth between the 60 water table, or where digging is difficult, for example channels 43. After the channels 43A-43C have been bed rock is at or near the surface, part or all of the heat filled with the rock indicated generally at 50, the duct storage structure may be built above the original soil 44 is put in place and additional cinder or concrete surface to form a small hill. In such cases only the lower blocks or tiles 51 are placed across the top of each part or none of the channels are formed by digging channel 43, and are spaced apart. The duct 44 also has 65 operation; much or all of the intervening earth between openings 48 in the wall thereof leading to the interior channels is added by filling operations. Such earth passageways of each of the blocks 51. Thus, the blocks material fill is generally cheaper and more available in 51 and 46 form transverse passageways at the top and properly sized rock, so that there are still advantages

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over a simple rock bed in which substantially all heat is landscaping relatively undisturbed, since grass and stored in such rock. small shrubbery can be installed directly above the In FGS. 3 and 4, the small hill or mound that is storage system.

formed will be easily appreciated. The ground surface It is interesting and for some cases, important to line is substantially along the bottom line of the chan observe that when cold is being stored, the channel nels shown, and the fill in between channels is added structure is generally warmer than the incoming air. material forming the hill or mound above the ground This causes a marked tendency for any water present in surface. The connecting ducts at the break line of FIG. the channels (whether liquid or frozen) to be evapo 3 for example are then connected into the channels in rated and carried away by the circulating air. The chan the hill in a suitable manner and can enter the building O nels and surrounding earth tend to dry out thoroughly. either below the ground surface as shown, or above the This tends to reduce heat storage capacity somewhat, ground surface if desired.

A simple way to build the heat storage system above and reduces or eliminates possibility of frost or snow plugging the interstices between rocks.

ground or partly above ground, when an adequate quantity of fill is economically available nearby, is to 15 cooler and will when

Conversely, heat is stored the channels are condense moisture out of the air unless use this fill to make a mound. It is then packed or al its dew point is below the rock temperature. This can lowed to settle and channels are dug and filled with result in water condensation in the bed, raising its stor rock in the usual way.

Only one cross channel is necessary in the present age capacity. Excess water would merely drain away. Should this mode of operation take place at tempera devices, but as many channels as necessary may be 20 tures below freezing, then trouble could result due to used. The rock used may be crushed rock or “pea” frost or ice freezing in the interstices. rock of suitable size, such as that used for driveways or What is claimed is:

for drain fields. Rock ranging from 4 inch or so in 1. A storage system for storing heat and cold and major dimension (diameter) up to about six inches in exchanging heat or cold with a fluid flowing from a major dimension, or even larger in some instances will 25 work. The rocks have to be of size to provide spaces for remote location comprising at least one narrow chan nel defined between two spaced, facing exposed sur free flow of air around and between them. Small sizes faces facilitate rapid addition or removal of heat but require cal depth of earth fill material, said channel having a verti more horsepower to force air through. Large sizes are dinal length, dimension, a transverse width, and a longitu more appropriate for cases of slow heat addition or being substantially 30 said vertical depth and longitudinal length removal. greater than the transverse width of This storage system has utility with respect to storing the channel, and said exposed surfaces of earth fill heat from solar heat collectors as previously stated. material being defined by the longitudinal length and Another significant use is in connection with a heat verticalofdepth dimensions of the channel, discrete par pump (more or less an ordinary air conditioning system 35 ticles rock-like material filling said channel, said which is arranged for convenient reversal so that it may particles permitting fluid passage through interstitial either heat or cool the interior of a building). In use spacesmaterial thereof, and said discrete particles of rock-like in said channel being in direct heat transfer with a heat pump, in the summer, a fan or blower can be used to rapidly circulate cold air through the storage relationship to both of the exposed surfaces of earth fill medium whenever the outside air temperature is suffi channel material, a first duct means fluidly connecting said ciently cool so that heat may be removed from the for fluid flow in a first direction between said storage medium. This would most likely happen at channel and said remote location, and second duct night though, perhaps, not every night, and therefore means connecting said channel for fluid flow in a sec the ability to store sufficient heat (cold) for some days ond direction between said channel and said remote of service is highly desirable. The ability to store heat 45 location, said second duct means being spaced from sufficient for weeks or even a few months appears prac said first duct means and physically separated from the tical with the present arrangement. Thus, when there is first duct means and communicating with said first duct a high air conditioning demand, heat is rejected from means only through said discrete particles to permit the house or building into the storage medium rather exchange of heat from a fluid circulated from said first than into the relatively warm outside air. This substan 50 duct means to said second duct means and through said tially reduces losses in the air conditioning equipment discrete particles initially with said discrete particles as for two reasons: (1) Air conditioners are more efficient the fluid is flowing and without circulating other fluids when the temperature difference against which they through said discrete particles, whereby a fluid such as work is reduced; and (2) less work is needed to move air that is circulated through said first duct means and heat from a building to a reservoir near the building 55 returned through said second duct means must pass temperature (the storage medium) rather than to an through interstitial spaces between said discrete parti environment whose temperature is farther away (the cles filling said channel, said exposed surface of earth outside ambient air). In winter, the reverse arrange fill defining said channel being of substantial size to ment is used. The heat pump is reversed. permit heat transfer between the earth fill material Where the bed is designed for only a few days heat or 60 adjacent said exposed surfaces and the discrete parti cold storage capacity, very little insulation or fill above cles filling the channel over a desired period of time. the channels is necessary. For the cases where many 2. The combination of claim 1 and means covering days or many weeks heat storage is desired, relatively said channels comprising an insulation layer placed thick insulation and covering is advantageous. The over said channel, and a waterproof layer covering said present system can be installed anywhere on a residen 65 insulation layer.

tial lot or other property, where channels can reason 3. The structure of claim 1 and a separate trench ably be dug. It is relatively insensitive to elevation, spaced from said first mentioned channel and encom exposure to the sun or shade, etc. Further, it can leave passing desired portions of said first mentioned chan

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nel, said separate trench being filled with insulation less than the depth dimension and length dimension of material. the slots to form narrow upright channel type openings 4. The structure of claim 3 wherein said separate defined by spaced apart, facing exposed surfaces of trench includes a water impervious layer. earthen fill material; particulate means filling each of 5. The storage system for heat or cold as specified in 5 said slots and comprising discrete rock-like material claim 1, wherein a plurality of individually, lateral permitting air passage through interstitial spaces channels are formed extending generally parallel to thereof from a first edge of each slot to a second edge adjacent channels, said channels being separated from of each slot opposite from the first edge; each slot each other by a desired thickness of earth fill material having a pair of duct means, the duct means of each into which heat may transfer from the discrete particles 10 pair extending along said first and second edges of each in each channel over a desired period of time. slot and each duct means substantially spanning the 6. A storage system for heat or cold as defined in width dimension of its respective slot, each of said duct claim 5, wherein said first and second duct means each means in a pair having a longitudinal axis extending include first conduits connected for fluid communica generally along one of the dimensions of said slot other tion with the first duct means and having openings 15 than the width for substantially the entire extent of said therein opening adjacent one of the edges of each of one dimension and the duct means in each pair being said channels, and second conduits connected for fluid spaced apart by said particulate means in said slot; each communication with the second duct means and having of said duct means having fluid transfer openings lead openings therein opening adjacent second edges of ing to said particulate means at desired locations along each of said channels generally parallel to the first 20 the length of the duct means, first conduit means from edges and spaced from the respective first conduit by the discrete particles in the respective channel, said aofsource the of heat or cold to provide flow of fluid to one duct means in each pair and second conduit first and second conduits in each channel substantially means providing spanning the width dimension of their respective chan duct means in eachreturn pair flow of fluid from the other and thereby from the one duct

7. The structure of claim 5 wherein said channels as means through the openings in the one duct means to separated by layers of earth material filled into a only and then to the other duct meansassociated the particulate means in the respective in each slot slot, mound above the normal ground level.

8. The storage system for storage heat and cold as thereby to force fluid to flow through said particulate specified in claim 5, wherein each of said channels has 30 exchange duringtheperiods means between duct means in each slot for heat of fluid flow, the exposed separate conduit means at the upper and lower edges surfaces of earthen fill defining each slot being in direct thereof, the separate conduit means at said upper and heat transfer relationship with the particulate means in lower edges of each channel forming transverse pas sageways for passage of fluid in a direction along the that slot to permit heat exchange between the particu length dimension of the respective channels, said con- 35 late means and earthen fill material over a desired duit means having openings therein to permit circula period of time.

10. The combination as specified in claim 9 wherein tion of fluid between the conduit means at the top of said duct means of each pair comprise a pair of vertical each channel and the conduit means at the bottom of the respective channels, and means fluidly connecting ducts edges positioned generally uprightly along the end of the respective slots and spaced apart by the the first duct means with the conduit means at the tops 40 of the channels, and the second duct means being flu longitudinal dimension of said slots.

idly connected to the conduit means at the bottoms of 11. The combination as specified in claim 9 wherein the channels. said duct means of each pair comprise generally hori 9. A rock filled channel system for storing heat or zontal ducts, one positioned at the bottom of each slot cold in large quantities at low cost comprising a plural- 45 and one positioned at the top of each slot, and said duct ity of vertical slots formed directly into earthen fill means having axes extending generally along the longi material, said slots having a vertical depth dimension, a tudinal length of their associated slot. length dimension and a width dimension substantially

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O -

UNITED STATES PATENT AND TRADEMARK OFFICE

CERTIFICATE OF CORRECTION

INVENTOR(S) : Frank D. Werner

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby Corrected as shown below:

Column 2, 1ine 7 'excpet' should be -- except--; Column 5, line 57 'opening 48' should be -- openings

O should be -- surfaces-- ; Column 9, 1ine 6, (Claim 5, line 2), 'lateral' should be -- laterally spaced--. eigned and Sealed this twenty-third Day of August 1977

Attest

RUTH C. MASON C. MARSHALL DANN O Attesting Officer Commissioner of Patents and Trademarks