D26 is a patent related to lighting. Specific classification USPC collates all American patent documents and other technical documents subordinate to the technical subject according to the technical subject, forming a certain number of document collections. USPC has two categories, each of which describes a different technical topic, while the other describes the technological process, structural features and functional features of the technical topics contained in the major category. The combination of "big category/small category" becomes a complete classification number, for example, the identifier "2/456" indicates the small category 456 (human body coverage) in the big category 2 (clothing). A subclass is the smallest grouping of USPC technical topics. Literature can belong to multiple literature collections, that is, literature can have multiple classifications. The technical content disclosed in the literature is the basis of the specified literature classification. USPC includes the following contents: 1) MOC (Classification Manual) is sorted according to all valid classifications of USPC. Its main content appears in the form of schedule, that is, MOC consists of various schedules. The big category table is a list of all the small categories in the big category, sorted from top to bottom according to the classification priority rule, that is, the one with the lowest complexity and comprehensiveness is located at the bottom of the table. The category table in MOC is sorted by numbers, for example, category 2 comes before category 224. At present, MOC has no paper format, and is only published in HTML and PDF electronic format, which can be obtained from USPTO website. 2) Definition of categories and subclasses. All major categories and most minor categories are defined. The definition of categories and subcategories is a detailed description of technical topics, so that documents can be correctly classified into subcategories in categories. 3) The index of American Patent Classification System is the index of MOC. It describes technical topics in alphabetical order and common terms, and is used to guide users into various subcategories roughly related to the technical topics of the MOC. 4) CDS is a database and automatic program for managing and storing confidential data. The database is named as Master Classification File (MCF), and its content is the classification information specified for documents. MCF can be used to confirm the classification of documents, and it can also be used to confirm all US patent documents containing USPC classification. 5)uspclus is the official guide to deal with the reclassification project, which includes classifying documents into USPC, creating new categories and subcategories, and modifying and canceling existing categories and subcategories. The classification announcement issued by the Patent Classification Office from time to time reflects the standards and examples of modifying USPC between two adjacent versions of USPCLASP. USPC can promote the effective retrieval of related technical documents. It is a necessary step for USPTO to classify American patent documents with USPC. In order to include new technical fields in more detail and cope with the increasing amount of literature, USPC is revised regularly. The revision of USPC needs to be reclassified, that is, the literature is reclassified by implementing the reclassification project. D 1 Edible products classified by American design patents
D2 clothing and menswear products
D3 Travel Goods and Personal Accessories
D4 brush project
D5 Textile or paper products, thin materials
D6 furniture
D7 Equipment for preparing or using foods and beverages without other characteristics
D8 Tools and Hardware D9 Food Packaging or Containers
D 10 measuring, testing or signal instrument
D 1 1 jewelry, badges and decorations
D 12 transportation
D 13 Equipment for generating, distributing and converting energy
D 14 Recording, Communication and Information Retrieval Equipment
D 15 machines with no other features
D 16 photographic and optical equipment
D 17 musical instrument
D 18 printing and office equipment
D 19 office supplies, art teaching supplies
D20 Sales and Advertising Equipment
D2 1 Games, toys and sporting goods
D22 Weapons, fireworks, hunting and fishing equipment
D23 Environmental heating and cooling, fluid handling and public health equipment
D24 medical and laboratory equipment
D25 Building components and structural components
D26 illumination
D27 Tobacco and smoking utensils
D28 Beauty and Cosmetics
D29 Safety, protection and rescue equipment
D30 animal husbandry
D32 Washing, cleaning or drying machine
D34 Equipment for handling materials or articles
D99 miscellaneous