US 4,750,249 AGranted

Pipe scraping tool

OwnerHenry A. Richardsoninventor

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Abstract

A pipe scraping tool for cleaning scale and other deposits from the exterior surfaces of pipes. The tool includes a plurality of inverted "U"-shaped scraper members each of which is carried by one of a series of interconnected hinged links, each link (preferably rectangular in shape) having a straight edge at each end thereof. These straight edges and the type of links used avoid excessive lateral movement of the links. The inverted "U"-shape of the scraper members provides relatively closely spaced cutting edges. The substantial length of the legs of the inverted "U"s helps avoid clogging of the tool by providing substantial exit spaces, for scale and other debris removed from the pipe exterior surfaces, between the cutting edges and the structure supporting those cutting edges, as well as between the cutting edges and the hinges that interconnect the links that carry the scraper members. Satisfactory, improved and preferred ratios of the depth and width of the spaces between adjacent cutting edges of a given scraper member of the tool are specified, as well as a similar series of ratios of the depth and width of the spaces below the hinges of the tool.

Claims17

Dependent claims

A pipe scraping tool for cleaning scale and other deposits from the exterior surface of a pipe, which comprises:

(a) a series of interconnected links, each of said links having a straight edge at each end thereof, the straight edges at opposite ends of a given link being substantially parallel to each other;
(b) a hinge connecting the end of each pair of immediately adjacent links, the last link at each end of said interconnected series of links being connected to a handle for grasping by the operator of said scraping tool, said series of links having a longitudinal axis extending from one of said handles to the other, a portion of said axis describing a substantially semicircular arc when said scraping tool is held by the user of the tool in a plane substantially perpendicular to the longitudinal axis of the pipe being cleaned, in its operative position for movement back and forth around and against said pipe;
and
(c) a plurality of scraper members, each of said scraper members having an inverted "U"-shaped cross-section and being rigidly attached to one of a succession of links in the middle of said series of links, each of said cross-sections including a bight portion and two legs of substantially equal length, the bight portion of said "U"-shaped scraper member being secured to the bottom surface of its associated link, and said two legs extending transversely across said associated link with one leg of said "U" adjacent one end of said link and the other leg of the "U" adjacent the other end of the link,
the two legs of said inverted "U"-shaped scraper member extending a substantial distance away from the bight portion of said scraper member and a substantial distance away from the hinges at each end of said link,
the free end portion of each of said legs having at least one cutting edge, each of said at least one cutting edge (i) being positioned transverse to the plane that includes the aforesaid substantially semicircular arc of the longitudinal axis of the series of interconnected links, and (ii) extending outward, on both sides of the link with which it is associated, a substantial distance beyond said link,
whereby, when said scraping tool is used to clean the exterior surface of a pipe, (a) a substantial space is present at all times between said exterior pipe surface and the bight portion of each of said "U"-shape scraper members for the ready exit of pieces of scale and other debris that are scraped from said pipe surface, (b) a substantial space is also present at all times between said pipe surface and the hinges at either end of each of said links for the ready exit of such scale and other debris, and (c) the effective cutting zone of said scraper tool extends a substanial distance on each side of the pipe scraping tool.

4 more elements

A pipe scraping tool for cleaning scale and other deposits from the exterior surface of a pipe, which comprises:

(a) a series of interconnected links, each of said links having a straight edge at each end thereof, the straight edges at opposite ends of a given link being substantially parallel to each other;
(b) a hinge connecting the ends of each pair of immediately adjacent links, the last link at each end of said interconnected series of links being connected to a handle for grasping by the operator of said scraping tool, said series of links having a longitudinal axis extending from one of said handles to the other, a portion of said axis describing a substantially semicircular arc when said scraping tool is held by the user of the tool in a plane substantially perpendicular to the longitudinal axis of the pipe being cleaned, in its operative position for movement back and forth around and against said pipe,
each of said hinges being of sufficiently tight construction to restrict each of said links, when said scraping tool is in use, to a position in which said straight edges at the ends of immediately adjacent links are generally parallel to each other at all times,
one end portion of each of said links forming a hinge pintle for the hinge between said link and an immediately adjacent link, a portion of said immediately adjacent link forming a journal in which said hinge pintle is seated;
and
(c) a plurality of scraper members, each of said scraper members having an inverted "U"-shaped cross-section and being rigidly attached to one of a succession of links in the middle of said series of links, each of said cross-sections including a bight portion and two legs of substantially equal length, the bight portion of said "U"-shaped scraper member being secured to the bottom surface of its associated link, and said two legs extending transversely across its said associated link with one leg of said "U" adjacent one end of said link and the other leg of the "U" adjacent the other end of the link,
the two legs of said inverted "U"-shaped scraper member extending a substantial distance away from the bight portion of said scraper member and a substantial distance away from the hinges at each end of said link,
the free end portion of each of said legs having at least one cutting edge, each of said at least one cutting edge (i) being positioned transverse to the plane that includes the aforesaid substantially semicircular arc of the longitudinal axis of the series of interconnected links, (ii) extending substantially parallel to said at least one cutting edge on the other one of said two legs, and (iii) extending outward, on both sides of the link with which it is associated, a substantial distance beyond said link,
whereby, when said scraping tool is used to clean the exterior surface of a pipe, (a) a substantial space is present at all times between said exterior pipe surface and the bight portion of each of said "U"-shaped scraper members for the ready exit of pieces of scale and other debris that are scraped from said pipe surface, (b) a substantial space is also present at all times between said pipe surface and the hinges at either end of each of said links for the ready exit of such scale and other debris, and (c) the effective cutting zone of said scraper tool extends a substantial distance on each side of the pipe scraping tool.

6 more elements

Dependencies are inferred from the claim text.