Class Notes

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use



Classification: 172/


This is the generic class for subject matter relating to working the earth in situ. Earth working involves physical treatment of the earth and includes beating, compacting, crushing, cultivating, cutting, digging, furrowing, harrowing, leveling, mixing, plowing, pulverizing, rolling, scraping, scratching, smoothing, and tilling.

The earth is usually worked by an earth working element carried on an apparatus traversing the ground but hand held tools such as hoes are also included.

This class also takes subject matter, not otherwise classified relating to the cutting and removal of sod or turf from the ground.

Apparatus comprising means other than earth working means supported on or attached to a vehicle for manipulation in a manner consistent with the use of the means as an earth working means is classifiable in this class if the means is identified in a claim by name only and the claim contains no feature otherwise inconsistent with classification in Class 172. However, lines with other classes have in many cases not been cleared so that where the bulk of the existing art has been classified on a basis other than indicated above such classification is continued.

(1) Note. CLAIMS NOT CONTROLLING IN PATENTS PRIOR TO 1930. Patents prior to 1930 have not necessarily been classified by claims so that the placement of these old patents does not necessarily indicate lines of classification. In view of the large numbers of old patents in this class many of these patents have been classified in accordance with their total disclosure. This is especially true of the patents in subclasses 332+. Most of the patents, however, regardless of their age have been placed in accordance with their claimed subject matter.



FOR INDUSTRIAL PURPOSES, TO COMPACTING EARTH FOR ROADS OR PAVEMENT AND TO WORKING HARD MATERIAL IN SITU Class 37, Excavating, generally relates to removing snow or to working the earth for industrial purposes as by making a ditch or moving earth by a conveyor or scoop. In many cases the devices found in Class 37 for these purposes are indistinguishable structurally from devices found in Class 172. Classification turns on emphasis for a certain use, such as snow removal or ditch digging. Class 37 formerly contained subclasses 143 through 181 entitled "Scrapers" which included subject matter relating to scraping the earth by means of a blade or such subject matter in combination with other earth working means such as harrows or rollers. The devices in these subclasses were typically road graders or bulldozers for working or moving the earth for industrial purposes. These subclasses were abolished and the art found in them was for the most part incorporated into Class 172 and is to be found in subclasses 4.5, 26.5, 26.6, 777-809 and other appropriate subclasses. Some of the art was specialized to ditch filling and was placed in Class 37 subclass 142.5. The remaining patents were not drawn to scraping blades or such blades combined with simple earth working means and were transferred to appropriate subclasses in Class 37 or other classes. Class 37, subclasses 104+, Railway Graders, and subclasses 381+, Road-Grader Type, were not cleared. Patents in these subclasses should be drawn to devices more specialized than the general utility scrapers or "road graders" which were classified in abolished subclasses 143-181.

Class 299, Mining or In Situ Disintegration of Hard Material, as the title indicates, generally provides for the working of hard earth material such as rock and also the working of ice in situ. However, a tool which is actually of general utility in earth working, such as a ripper tooth or scraper and traverses the earth without relative movement with respect to its support (as by rolling or cyclical driving) is classifiable in Class 172 even if solely disclosed for disintegrating rock.

Class 404, Road Structure, Process, or Apparatus, subclasses 117, 121, and 122+, for a roller device which performs a simple compacting function on the earth. See the note to Class 172, under the class definition of Class 404.


Many of the patents relating to earth working devices claim joints between parts of the device. A claim to a joint between two disclosed earth working portions of an earth working apparatus, e.g., a claim to a joint between a plow share and moldboard, is classifiable in Class 172, subclasses 681+. Also, a claim to an overload release joint between implement parts, e.g., between a tractor and a device solely disclosed as an earth working type of implement, is classifiable in Class 172, subclasses 261+ and a claim to a

spring biased joint for biasing an earth working tool is classifiable in Class 172, subclasses 705+. However, other claims to joints, per se, are classifiable in the various classes relating to joints. Thus, joints of general application are classifiable in Class 403, Joints and Connections. An articulated joint between a tractor and a trailing vehicle, as long as that vehicle is not solely disclosed as an implement, is classifiable in Class 280, Land Vehicles, subclasses 400+.

The Search Notes below also contain lines with other classes.



7, Compound Tools, appropriate subclasses for miscellaneous compound tools, especially

115, for a cutter combined with a pitch fork and subclass 116 for a cutter combined with a spade or shovel (e.g., a bayonet and a shovel). Hand tools comprising combinations of various earth working portions are classifiable in Class 172, Earth Working.

15, Brushing, Scrubbing, and General Cleaning, appropriate subclasses for cleaners, including scrapers. Class 172 takes cleaners for cleaning earth working parts, which cleaners are intended to be attached to the earth working apparatus. 16, Miscellaneous Hardware,

110+, for handles for earth working devices, such as plows or hoes.

29, Metal Working,

14, for machines and processes of making plow and cultivator irons, subclasses 891+ for processes of making agricultural devices, and see the subclasses there cited.

30, Cutlery, appropriate subclasses, for cutters of general utility and cutters for merely making a slit in sod. A cutter for earth working purposes such as making a slit in the soil (e.g., a colter) is classifiable in Class 172. Thus a patent to a cutter with a claim restricted to earth working or a sole disclosure of earth working is classifiable in Class 172, except that a patent to a hand device with the cutting edge extending generally in the direction of the handle is classifiable in Class 30 even though it is restricted to earth working. Also a tool for merely cutting a plant below the surface of the earth is classifiable in Class 30.

37, Excavating,

196+, for snow- removing apparatus which may be identical

with earth working apparatus except that it is disclosed as principally for snow removal, subclasses 307+ for dredging apparatus, subclasses 347+ especially subclasses 366+ for ditchers which may be very similar to earth working apparatus for Class 172 except that they are disclosed as making an industrial ditch or trench rather than a furrow, by more than mere scraping operation, subclasses 104+ for apparatus specialized to forming the bed or slopes of a railway, subclasses 381+ for apparatus specialized to working on roads and involving something more than mere scraping or earth working apparatus of general utility, subclasses 394+ for cable operated apparatus including cable operated scrapers involving more than the scraper, per se, and a cable attached to the scraper, subclasses 403+ for a scraper convertible to or combined with a scoop, shovel or other material pick up means, subclasses 411+ for scoops which are distinguishable from scrapers classified in Class 172 in that they have a bottom for transporting material, and appropriate subclasses for digging or moving earth in general.

47, Plant Husbandry, appropriate subclasses, especially

1.01, and 58.1 for subject matter relating to earth working combined with other functions relating to plant husbandry such as heating the earth or spraying a plant. However, a moldboard type plow with heating means for the plow is classifiable in Class 172 subclass 755.

56, Harvesters, appropriate subclasses for subject matter relating to severing or chopping of crop material without disturbing the soil and also subject matter relating to gathering or raking crop material without substantially disturbing the soil. The line is essentially one of disclosed use. If a device is described as a nonearth disturbing harvesting device the patent is placed in Class 56 rather than Class 172 even if the structure claimed is the same as that which may be found in Class 172. An exception is that if a harvester is claimed by name only and the claim is otherwise drawn to merely a mounting or manipulating means which is consistent with the functioning of the named harvester as an earth working device then the patent may be classifiable in Class 172.

With respect to the stalk chopper art, if the chopper is disclosed as one which operates by the action of a cutter member against the ground, without a ledger plate it is assumed that the soil is disturbed and classification in Class 172 results. Choppers operating above the ground level are classifiable in Class 56. Generally Class 172 takes the combination of or the conversion between a Class 56 apparatus and a Class 172 apparatus, or an apparatus disclosed as having either an earth working or a harvesting function without change. Thus a Class 172 type lawn edger combined with or convertible to a harvester is found in Class 172, subclass 14, the combination of other types of Class 172 devices with a harvester is in

Class 172, subclasses 27+ and the combination of a Class 172 device with a rake is in Class 172, subclasses 29+. An exception to the above is that a hand rake combined with or convertible to an earth working means is classifiable in Class 56, subclasses 400.04+.

60, Power Plants,

325+, especially subclass 427 for hydraulic-type power plants operated by liquid supplied from a pump. Many such power plants are used in earth working apparatus. A claim to a power plant for an earth working apparatus reciting only a tractor mounting for the plant and a rockshaft actuated by the power plant is classifiable in Class 60. If the claim goes beyond this and claims some detail of the apparatus which may be only a lift arm on the rockshaft or a draft sensing means it is classifiable in Class 172.

72, Metal Deforming,

462+, for dies for forming plow and cultivator irons.

74, Machine Element or Mechanism, appropriate subclasses for machine elements and mechanical movements, especially

11+, for power take-offs.

76, Metal Tools and Implements, Making,

85, for attachments other than abrading attachments for sharpening earth working tools. An earth working apparatus combined with a sharpening device is in Class 172, subclass 437. However, when the earth working apparatus as claimed is only a support for the attachment the claim is classifiable in Class 76.

91, Motors: Expansible Chamber Type, appropriate subclasses for servomotors, per se. Many such servomotors are used in earth working apparatus. A claim to a servomotor for an earth working apparatus reciting only a tractor mounting and rockshaft operated by the motor is classifiable in Class 91. However, further detail such as a lift arm on the rockshaft or a draft sensing means causes classification in Class 172.

104, Railways, 169, for apparatus for reciprocating an earth working device, claimed by name only, over the ground and subclass 244.1 for a vehicle or earth working device claimed by name only guided along a field by a furrow feeler. Class 172, subclass 23+ has significantly claimed earth working apparatus driven from or guided by a stationary object or previously formed furrow.

111, Planting, appropriate subclasses for earth working means combined with planting means, especially

118+, for earth working means combined with means for

inserting liquid or gas into the soil, subclasses 25+ for planting means with earth marking means, subclass 33 for earth marking means comprising means to make an intermittent mark in the earth to indicate the points where material should be planted, subclasses 52+ for frame arrangements, subclass 82 for hand propelled planters, and subclass 99 for dibbles. A Class 172 device generally may comprise the earth working subcombination of a planting device. A planter may be recited by name only as a support for an earth marker or an earth working tool in a claim classifiable in Class 172. A support for an earth working portion identified as a planting boot in a claim is not considered too much for Class 172.

152, Resilient Tires and Wheels, appropriate subclasses for tires and wheels which may be structurally similar to earth working apparatus but are not intended to have an earth working function.

171, Unearthing Plants or Buried Objects, appropriate subclasses for subject matter relating to unearthing and separating an object from the earth (e.g., a potato digger). A Class 172 device may cut plant roots as it traverses the ground or may turn a furrow which has objects in it such as potatoes but devices in Class 172 do not separate an object from the adjacent earth. A Class 172 device may be a subcombination of a Class 171 device; for example, a plow for Class 172 may lift earth with potatoes in it, the potatoes then being separated from the earth, the complete device being classifiable in Class 171.

173, Tool Driving or Impacting, appropriate subclass for subject matter directed to driving or impacting a tool, when such subject matter includes combined features peculiar to tool driving, but which does not include features limiting the subject matter to a specific tool art, such as specific shape of the work contacting portion of a tool, related tools, or an opposed work support, and see particularly

184+, driving or impacting means mounted on a wheeled vehicle. Class 172 has not been cleared as to subject matter in conflict with this line.

175, Boring or Penetrating the Earth, appropriate subclasses for subject matter relating to forming elongated holes in the earth. Apparatus for forming a plurality of small holes in the earth for aerating the soil or for like purposes is classifiable in Class 172,


180, Motor Vehicles,

14.1+, for vehicle trains comprising a tractor and a trailing vehicle which may be an implement claimed by name only, subclasses 53.1+ for devices in which the motor of the motor vehicle is used as a source of external power for a device which may be an implement claimed by name only, and subclass 401 for power steering devices which may be controlled by a feeler element running in a furrow. An implement described in a claim as comprising a frame and an earth working means carried thereby is considered to be claimed by more than name only so that the claim would be classifiable in Class 172. The line between Class 172 and subclasses 53.1+ of Class 180 is set out in the Search Class Note of subclass 35 in class 172.

192, Clutches and Power-Stop Control,

62, for plow-lifting type clutches, per se.

241, Solid Material Comminution or Disintegration, appropriate subclasses for subject matter relating to comminuting or disintegrating material other than the earth in situ.

254, Implements or Apparatus for Applying Pushing or Pulling Force, appropriate subclasses for lifting means of general utility for lifting a load, which means may be structurally similar to a means for manipulating an implement.

280, Land Vehicles, appropriate subclasses for the running gear or other feature of a general utility land vehicle, not restricted by disclosure to an earth working or harvesting implement. Attention is directed to

1.5, for a vehicle with a means for engaging the body of a walking attendant; subclasses 6.15+ for a vehicle including means, interposed between the vehicle body, chassis, or frame and running gear thereof, for altering height or levelness of the vehicle body, chassis, or frame; subclasses 32.5+ for a vehicle with a worker's support or shade; subclass 32.7 for a vehicle including a riding attachment; subclasses 43+ for a vehicle including a wheel vertically movable relative to the running gear for the purpose of altering a dimension of the vehicle or a part thereof; subclass 47.11 for a vehicle including steering of other than a mere swinging axle by an attendant positioned about, rather than upon, the vehicle; subclasses 47.131+ for a tiltable vehicle stabilized by an article or an attendant; subclasses 47.34+ for handle-propelled vehicles; subclasses 82+ for tongue trucks; subclasses 98+ for vehicles having running gear specifically constructed to enable execution of arcuate travel within a reduced radius of curvature (i.e., short turn); subclass 108 for general utility vehicles including tongue antivibrators; subclasses 124.1+ for general utility vehicle running gear including suspension means; subclasses 137.5+ for general utility vehicle running gear including a turnable axle lacking suspension means; subclasses 160+ for means for fending obstacles from contact with the wheels of a vehicle; subclasses 400+ for an articulated vehicle or plural interconnected vehicles (i.e., vehicle train); subclasses 763.1+ for a vehicle with a retractable ground support; subclasses 771+ for vehicles including occupant controlled steering; subclasses 847+ for vehicle dust or mud guards; or

subclasses 855+ for wheel scrapers and cleaners. Further, regarding an articulated vehicle or vehicle train as provided in subclasses 400+ of this class (Class 280), particular attention is directed to subclasses 405.1+ for a load distribution connection between sections of the articulated vehicle or the plural vehicles, subclasses 411.1+ for multiple trailing vehicles, subclass 414.5 for a trailing vehicle having a vertically adjustable wheel, subclasses 415.1+ for a convertible interconnection between the articulated vehicles, subclass 419 for a steering connection between articulated vehicles, subclasses 420+ for articulated vehicles with service connections therebetween, subclasses 442+ for a wheel on a trailing vehicle steered by articulative movement between the vehicles, subclasses 446.1+ for condition responsive draft connections, subclasses 449+ for overload releasing draft connections, subclasses 456.1+ for plural laterally adjustable draft connections, subclass 476.1 for a wheel draft connection, subclasses 477+ for connection facilitating means in a draft connection, and subclass 490.1 for a vertically adjustable draft member, the adjustment being merely for the purpose of placing the draft member at a proper height for facilitating the connection between the articulated vehicles.

294, Handling: Hand and Hoist-Line Implements,

49+, for hand forks and shovels. Hand forks and shovels are distinguished from Class 172 apparatus such as a hand hoe in that the row of tines or blade extends in the general direction of the handle from an end thereof and is designed to engage and lift a load.

299, Mining or In Situ Disintegration of Hard Material, appropriate subclass for subject matter relating to recovering valuable material from the earth or breaking up hard, solid material in situ. In working the earth surface, the line between Class 172 and Class 299 turns on described hardness of material worked, Class 299 taking a cutter or device for working hard solid material in situ. Clay type earth or loose gravel is considered soft material whereas solid rock, coal or road pavement is considered hard material. However, a device for merely drawing a cutter back and forth like a plow even in a hard surface is classified in Class 172 if specific cutter structure is not recited.

301, Land Vehicles: Wheels and Axles, appropriate subclasses, especially 41.1+, for wheels which may be structurally indistinguishable from earth working tools but which are not intended to work the earth.

384, Bearings,

157, for a plain bearing and 460 for an antifraction bearing for plow or colter disks which may include the bearing support.

403, Joints and Connections, appropriate subclasses for a joint between two members which does not involve any structure of the members other than that which cooperates to effect the joint.

404, Road Structure, Process, or Apparatus,

117, for an earth compacting roller with vibrating or impact means, subclass 121, for a sheep's foot roller, subclasses 122+, for a rotating drum, roller or tire to compact earth and subclasses 133.05+, for earth tamping means.

414, Material or Article Handling, appropriate subclasses.

418, Rotary Expansible Chamber Devices, for rotary expansible chamber-type pumps or motors, per se.

451, Abrading,

415+, for an abrasive attachment for sharpening earth working tools. An earth working apparatus combined with a sharpening device is in Class 172, subclass 437. However, where the earth working apparatus, as claimed, is only a support for the attachment, then classification is in Class 451.

492, Roll or Roller, for a nonearth working roll, per se, not elsewhere provided for, and see the notes thereunder. D8, Tools and Hardware,

1+, for tools and implements for agriculture, forestry and horticulture.

D15, Machines Not Elsewhere Specified,

10+, for agricultural or construction machinery.



A device comprising both a means for imparting movement to an element and a means for holding the moved element against returning to a position from which it has been moved. Thus, an actuator may comprise a servomotor, a mechanical power take-off from a motor or rolling wheel, a hand operated lever and ratchet or merely a handle and a bracket for holding the element moved by the handle in position. In the case of a mere handle actuator, however, the handle must be intended to be used merely to move an element to an adjusted position where it is held in place by a holding means. If the handle is intended to be used by an attendant so as to hold an element in intermediate positions by continued application of force by the attendant then the handle is not considered an actuator. See subclasses 329+ for devices with such handles. If the handle is disclosed as usable as an actuator to merely

move and hold and, alternatively, also as a guiding means to move and hold by force exerted by the attendant then the handle is considered to be both an actuator and an attendant hold means and is classified accordingly in the first appropriate subclass and cross referenced down if necessary.

A device comprising merely a means for moving by direct application of draft force is not considered an actuator. For example, an implement hitched to a tractor and provided with a latch and a movable hitch whereby the draft force of the tractor on the movable hitch moves an earth working element with respect to the implement frame and the latch holds the element in different positions is not considered to be provided with an actuator, as the term is used in this class. See subclass 605 for such devices.

Also, a device comprising merely a screw bolt or the like is not considered an actuator, being merely a clamping or an adjusting means.


An adjective describing the capability of two parts of being selectively held in different positions with respect to one another by some means other than an attendant. A mere clamp which cooperates with a member such that by loosening the clamp the member could be set in any desired position and reclamped (e.g., clamp and spike tooth) is not considered to be an adjusting means. However, any specific structure such as selectively usable apertures, teeth, slots, etc., for the purpose of permitting the selective change of the relative positions of two parts is included under this definition. Despite the above limitation on the meaning of "adjustable" if a claim emphasizes the feature of adjustability it is classifiable in an "adjustable" subclass even if structurally the feature comprises a mere clamp.


Synonymous with "tool".


A combination of parts comprising an earth working device. It may mean merely an earth working portion or a complex combination of parts including a tractor. Usually it indicates a complete device which as an entity may be readily attached to a tractor in the field.


A direction which is transverse of the line of draft of a tool over the earth unless some other meaning is clearly indicated by the context.


A direction which is parallel to the line of draft of a tool over the earth unless some other meaning is clearly indicated.


That portion of the apparatus which actually works the earth.