MANUAL PIPE CUTTER

Abstract: A manual pipe cutter that comprises a cutting disc (29) and a cutter-pressing jaw (27) to press the cutting disc edgew­ ise against a pipe to cut it, and has a pushbutton (32) and gear (33-36) arrangement for convenient operation and forceful pressing of the cutting disc (29) edgewise against the pipe (25). This manual pipe cutter further comprises a body (10) defin­ ing a cutting head portion (13) and a handle portion (14), a cutting head (16) rotatable in the cutting head portion (13) of the body (10) and cooperatively forming with it a pipe passage and an open mouth (15) to position a pipe (25) transversely into the pipe passage, a pawl and ratchet to rotate the cutting disc (29) around the pipe, and a system (30, 31, 33) to release the movable jaw (27) and return it to its outermost position. In another simpler and less automatic embodiment, the push­ button and gear arrangement, together with the disc-­ releasing system, is replaced by a manually-rotated knob at the end of a bolt displacing a cutting disc-carrying jaw towards and away from the pipe.

Description: bIanual Pipe Cutter ¯±his invention relates to a pipe cutter of the hand tool type. DESCRIPTION OF THE PRIOR ART Manual pipe cutters of the above type are described, for instance in applicant's own prior U,S. Patents numbers 4,157,615 dated June 12, 1979 and 4,177,557.dated December 11, 1979 In these known cutters, the rotatable cutting head was made in one piece and, consequentsy, the various parts of the pipe cutter were difficult to assemble and to disassemble. Moreover, the cutting disc was mounted for rotation about a fixed 'axis relative to the cutting head and, theretore, was difficult of access for removal and sharpening. Thene known cutters further include a screw-and-knob arrangement to press the cutting disc against the pipe to be cut. This screw-and-knob arrangement protrudes from the cutting head, so that the pipe cannot be cut when it is very close to an obstruction. OBJECTS OF TIlE INVENTION It is a general object of the present invention to provide a manual pipe cutter of improved construction and more effcient operation. It is another object of the invention to provide a manual pipe cutter which is easier to assemble and disassemble and in which the cutting disc can be easily removed for sharpening or replacement. It is another object of the invention to provide a pipe cutter in which the above-mentioned screw-and-knob arrangement is replaced by a gear-and-pushbutton system to progressively displace the cutting disc for pressing engagement with a pipe to be cut, this arrangement occupying much less room, so that a pipe may be cut even when very close to an obstruction. It is an object of the present invention to provide a manual pipe cutter which includes a pushbutton-and-gear arrangement for convenient operation and strong pressing of a cutting disc edgewise against a pipe to cut it. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects and advantages of the present invent4.c.i will be better understood with reference to the following detailed description of preferred ¯mbodiments thereof, which are illustrated, by way of example, in the accompanying drawings, in which: : Figure 1 is a perspective view of a manual pipe cutter according to a first embodiment of the present invention; Figure 2 is a side view of the same manuel pipe cutter; Figure 3 is a top view of the same manual pipe cutter; Figure 4 is a cross-sectional view of the head portion of the pipe cutter as seen along line 4-4 in Figure 3; Figure 5 is a cross-sectional view as in Figure 4, but looking in the opposite direction relative to the arrows in Figure 3; Figure 6 is a side view of the cutting head forming part of the illustrated manual pipe cutter; Figue 7 is a bottom view of the head portion of the same pipe cutter; Figure 8 is a cross-sectional view as seen along line 8-8 in Figure 2; ; Figure 9 is a top view of a gear arrangement with an associated rack shown in cross-section and forming part of the pipe cutter; Figure 10 is a cross-sectlonal view as seen along line lO-lO in Figure 9; Figures 11 and 12 are side views of a pushbutton and associated gears forming part of the same pipe cutter to progressively increase the bite of the cutter into the pipe being cut; Figures 13 to 17 inclusive are schematic side views illustrating the sequence of operation of the manual pipe cutter shown in more detail tn the preceding figures; Figure 18 is a side elevation of a second embodiment; ; Figure 19 is, a plan section along line 19-l9 of Figure 18; Figure 20 is a longitudinal section along line 20-20 of Figure 19; Figure 21 is an exploded perspective view; Figure 22 is a front end elevation; Figure 23 is a longitudinal section similar to that of Figure 20, but with the rotary head removed; and Figures 24 and 25 are sections taken along line 24-24 and 25-25, respectively, of Figure 18. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The illustrated manual pipe cutter of Figures 1 to 17 comprises a body lO, made of two halves 11 and 12 cooperatively form ing a cutting head portion at 13 and a handle portion at 14. The cutting head portion 13 defines a pipe passage extending roans versely through it and has a Cutout at 15 forming an open mouth communicating transversely with the pipe passage to allow relative transverse displacement of a pipe inward into the pipe passage in the cutting head portion. A cutting head 16, made of two half-parts secured together by bolts, is rotatably mounted in the cutting head portion between the corresponding cutting head portions of the spaced-apart halves 11 and 12 of the body 10. Thus, the cutting edge portions of the two halves of the body define a pair of inner faces 17 and 18 which are mutually facing each other and engage the opposite sides respectively of the cutting head 16. The inner face 17 is formed with ratchet teeth 19 serially arranged circularly around the pipe passage. As shown in Figure 8, a bore extends transversely into the cutting head from the face adjacent the ratchet teeth 19. A pawl, in the form of a pin 20, is slidable in that bore and is outwardly biased by a spring 21, such that its outer pointed end operatively abuts against the adjacent tooth 19. The ratchet teeth 19 and the pawl 20 are constructed and arranged such that, when the handle 14 is lowered in the direction of the arrow 22, as shown in Figure 16, the body 10. rotates the cutting head in the clockwise direction, as shown by the arrow 23. When the handle 14 is pivoted in the direction of the arrow 24, as shown in Figure 14, the pawl 20 and ratchet teeth 19 allow the body 10 to idly pivot relative to the cutting head 16, such as when the latter bites a pipe 25. Thus, the reciprocative pivoting of the handle 14, as shown by the arrow 26, causes only unidirectional rotation of the cutting head 16 in the direction of the arrow 23, as shown in Figure 16. The cutting head 16i as the head portion 13, is provided with a pipe passage and a cutout forming an open mouth to insert the cutter endwise around the pipe 25 to be cut. A cutter-pressing jaw 27 is slidably mounted on the cutting head and is slidable in a predetermined direction transversely relative to the pipe passage and to the open mouth of the cutting head. A pair of guide rollers 28.are rotatively carried by the cutting head diametrically opposite to the cutter-pressing jaw 27 relative to the pipe passage. This allows operative displacement of the jaw toward the rollers to hold a pipe 25 between the rollers 28 and a cutting disc 291carried by the jaw. The cutting disc 29 is arranged to engage the pipe 25 edgewise to cut it transversely. A blade spring 30 is fixed at one end to the cutting head and at its other end to the cutter-pressing jaw 27 and is made and arranged to retract the latter in opposite direction away from the rollers 28. A toothed rack 31 is fixed to the cutter-pressing jaw 27 and is bodily slidable endwise in the direction of the rollers 28. A oushbutton-and-gear arrangement is provided to progressively disl)lace or slide the jaw 27 in the direction of the rollers 28 as the cutting operation progresses. The pushbuttonand-gear arrangement includes a pusbbutton 32 and a ratchet-andgear system operatively connecting the pushbutton 32 to the toothed rack and arranged for controlled operation of the same. The ratchet-and-gear system includes a first pair of gears 33 and 34 carried by the rotatable cutting head 16 and a second pair of gears 35 and 36 carried by the body 10 and dis placeatle with it translatively. The gears 33 and 34 are in meshing engagement one with the other and are translatively rotatable with the rotatable cutting head. The gear 33 is a doubLe-toothed wheel or gear Including one axial side 37 that drives the other axial side 38 bodily with it. The toothed wheel or gear forms a ratched wheel 37 which meshes with the gear 34. A pin 39 is carried by the rotatable cutting head 16 and is spring biased into engagement as a pawl between a pair of teeth of the side 27 of the double gear. This forms a pawl-and-ratchet assembly to allow only unidirectional rotation of the gears. The side 38 of the.double gear 33 has a couple of teeth removed, thus forming a non-toothed circumferential portion 4Q that produces a detent to release the toothed rack 31 and allow the jaw to be retracted by the spring blade 30 away from the rollers 28 at the end of one cut through a pipe 25. The dears 34 and 35 form intermediate connection gears which mesh one with the other cyclically; that is, only when for each rotation of the cutting head 16, the latter has its mouth registering with the mouth of the head portion 13. Then gears 35 and 36 mesh one with the other. A gear sector 41 meshes with the intermediate connection gear 35 and is pivoted to produce a pivotable pawl to block the gears 35 and 36 against rotation in the direction opposite to the direction indicated by the arrow 42 in Figure 17 during a portion of the cycle of operation. This is done by abutment of the gear sector 41 with a pin 43. The pushbutton 32 includes a pushbutton head 44 which is secured at the outer end of an arm 45 that is pivoted at its other end around the axis of the gear 36. The pushbutton also includes a plunger 46 that is biased by a spring 47 toward pawl-like engagement with an adjacent tooth of the gear 36. A spring wire 48 engages the pivotable arm 45 to bias the same angularly away from engagement of the plunger 46 with a tooth of the gear 36. The plunger 46 is shaped to be wedged away from the gear 36 upon abutment with a blade 49. By pushing on the head 44 of the arm 45, the gear 36 is rotated and this also rotates the gears 35, 34, and 33 and pivots the gear sector 41 away from the abutment pin 43, as shown by the arrows in Figure 13. Then, the cutter-pressing jaw.27 slides toward the¯rollers 28 and the cutting disc 29 can thus cut deeper into the pipe 25. When tie head 44 of the arm 45 is released, the plunger 46 frees the gLar 36. Upward pivoting of the handle 14 frees the gear 35 and the spring wire 50 of the gear sector 41 then pivots the latter until its abutment with the pin 43; this is shown by the arrows in Figure 14. As afore mentioned, the up-anddown pivoting of the handle 14, as indicated by the arrow 26, causes rotation of the cutting head 16 and of the cutting disc 29 in the direction of the arrow 23 around the pipe to cut it; this is shown in Figure 15. As shown in Figure 16, when a turn of the cutting head has been completed, the connection gears 34 and 35 mesh again one with the other to repeat the operation of the arm 45 to further slide the jaw 27 toward the rollers 28. Figure 17 shows the movements occurring upon release of the head 44 and by action of the spring wire 50 on the gear sector 41. As mentioned, when the jaw 27 has reached the end of its course toward the rollers 28, the non-toothed portion 40 of the gear 33 registers with the toothed rack 31 and the jaw 27 is returned by the spring 30 to its starting position. The second embodiment of the invention is shown in Figures 18 to 25. A body 55 is made of two halves 56, 57 secured together by bolts 58 and forming a cutting head portion 59 and a handle portion 60. The cutting head portion 59 defines a pipe passage extending transversely through it and has a cutout 61 forming an open mouth communicating transversely with the pipe passage to allow relaitze transverse displacement of a pipe inward into the pipe passage in the cutting head portion. A cutting head 62 is rotatably mounted between the corresponding cutting head portions of the spaced-apart halves 56 57 of body 55. The cutting head 62 is made of two half-parts 62a,62b, secured together by bolts 63 for ease of assembly and disassembly. The inner face 64 of the cutting head portion 59 of body half 56 is formed with ratchet teeth 65 serially arranged circularly around the pipe passage, as shown in Figures 23, 24. A bore extends transversely into the cutting head 62 from the face adjacent the cutting teeth. A pawl 66 is slidable in the bore, being outwardly biased by a compression spring 67, such that its pointed end operatively abuts against the adjacent tooth 65. There are preferably two angularly-spaced pawls 66, as shown in Figure 23, so that there is always a pawl engaged with the ratchet teeth independenly of the rotary position of the cutting head 62 with respect to body 55. As in the first embodiment, when the handle portion 60 is pivoted in a reciprocating manner about the pipe, aF shown by arrows 68 in Figure 23, the cutting head 62-will rotate in only one direction. The cutting head 62 is provided with a pipe passage and a cutout forming an open mouth to insert the cutter endwise around the pipe to be cut when the mouth of both the head portion 59 and the cutting head 62 are in angular register, as shown in Figure 18. A cutter-pressing jaw 69 is slidably guided on the cutting head 62, being slidable in a predetermined direction transversely of the pipe passage and open mouth of the cutting head. The Jaw 69 carries a cutting disc 70, which is freely rotatable about a transverse pin 71. The cutting head 62 carries a pair of pipe-engaging rollers 72 freely rotatable about transverse pins 73. The rollers 72 are arranged diametrically opposite to the cutting disc 70. The latter is arranged to engage a pipe edgewise to cut it transversely. The cutter-pressing jaw 69 is manually displaced in accordance with double arrow 74, shown in Figure 20, by means of a bolt or screw 75 threaded in a threaded bore of jaw 69. The screw 75 is an integral extension of a non-threaded spindle portion 76 freely rotatable within complementary bore portions 77,78 forming a bore at the junction of the two half-parts 62, 62b of the cutting head 62 and held against axial diaplacement by shoulders 79,80 integral with spindle portion 76 and lapping the ends of said bore. The protruding end of the spindle portion 76 is provided with a manually-operated knob 81 which, together with all the parts of the head and spindle protruding from the circular periphery of the cutting head 62, is adapted to freely pass through an opening 82 formed by the body halves S6,57 during relative rotation of the cutting head 62 with respect to the body 55. Since jaw 69 and spindle porticrn 76 are located at the junction of the two half-parts 62a, 62b, they can be easily assembled and disassembled.

Claims: Claims 1. A manual pipe cutter comprising a body including 8 cutting head portion having a pipe passage extending therethrough, a cutting head rotatable in the cutting head portion substantially around the pipe passage, a cutter-pressing Jawfrounted on the cutting head and displaceable in Åa predetermined direction transversely across relative to the pipe passage, a toothed rack fixedly secured to the cutter-pressing jaw and displaceable bodily with the latter and endwise in said predetermined direction, a ratchet and gear system connected to the toothed rack and constructed and arranged to move and hold the latter relative to operative displacement of the cutter-pressing jaw in said predetermined direction, and a manual actuator mounted on said body, connected to the ratchet and gear system and constructed and arranged to actuate the same and produce the operative displacement of the cutter-pressing jaw in said predetermined direction. 2. A manual pipe cutter as defined in claim 1, wherein the ratchet and gear system includes at least one toothed wheel operatively connected intermediate the manual actuator and the toothed rack and constructed and arranged to operatively drive the latter in said predetermined direction, a pawl operatively holding the toothed rack and cutter-pressing jaw against bodily displacement in opposite direction relative to said predetermined direction, and a detent device constructed and arranged to release the toothed leck for backward displacement in said opposite direction. 3. A manual pipe cutter as defined in claim 2, wherein the manual actuator include a pushbutton operatively connected to said one ratchet, wheel and selectively rotating the same upon actuation, to produce, the#perstive displacement of the, cutterpressing Jaw in said predetermined direction. 4. A manual pipe cutter as defined in claim 32 wherein the detest device includes a second toothed wheel bodily rotatable with said one toothed wheel; operatively meshing with the toothed rack, and having a non-toothed circumferential portion enmeshing the second toothed-wheal from'the toothed rack upon cyclic rotation into regis"tra'tion therewith, thereby producing detent of the toothed' ra"c'k for the backward displacement thereof. 5. A'manual pipe cutter SB defined in claim 4, wherein'the ratchet and gear system includes Åa first pair of gears and a second pair of gears, the first pair of gears is mounted on the cutting head and is translatively rotatable therewith, the second pair of gears is mounted on said body'operatively'between the pushbutton and the first pair of gears, and' eÅach of said pairs of gears includes one intermediate connection gaar selectively meshing with the intermediate connection gear of the other pair of gears upon cyclic registration of thettwo pairs flf gears produced by rotation of the cutting head relative to said body. 6. A manual pipe cutter'as defined in claim 5, wherein the ratchet and gear system'includes a gear sector pivotable adjacent the intermediate connection gear of the second pair of gears and forming a pivotable pawl operatively holding the intermediate connection gear o the second pair of gears fixedly in the path of displacement of the intermediate connection gear of the riret pair or gears and constructed and arranged for operative meshing together or the intermediate connection gear. 7. A manual pipe cutter as defined in claim 6, wherein the pushbutton includes a head; a spring-biased plunger operatively pushed against a tooth of the other gear of the second pair of gears and operatlvely rotating the latter upon pushing on the pushbutton head. 8. A manual pipe cutter as defined in claim 7, wherein a cutting disk is carried by the cutter-pressing jaw and the latter is slidably mounted on the cutting head and slideable in said predetermined direction toward adgewise cutting engagement against a pip. positioned in the pipe passage. 9. A manual pipe cutter as defined in claim 8, wherein the cutting head portion forms a pair or apaced-apart inner races mutually facing each other and extending around the pipe passage, on opposite sides of the cutting head, one race is formed with ratchet teeth serially and operatively arranged around the pipp'-. passage, and a pawl is mounted on the cutting head, biased into operative engagement with the teeth or the ratchet teeth of asid one race and constructed and arranged to allow pawl and ratchet control or the rotation of said body around the cutting head. 10. A manual pipe cutter as defined in claim 9 2 wherein the cutting head,or generally annular configuration, extends annularly around the pipe passage, has a cutout worming a radially-extending open mouth operatively registering with the open mouth of the cutting head portion, and includes a pair of guide rollers rotatively mounted thereon tor guiding engagement tiiith a pipe positioned lengthwise into the pipe passage. 11. A manual pipe cutter as defined in claim 10, wherein the cutting head includes a spring operatively engaging the cutter-pressing jaw and operatiusly biases the same in said opposite direction away from the guide rollers. 12. A manual pipe cutter comprising a body including a cutting head portion having,± pipe passage extending therethrough, a cutting head rotatable in the cutting head portion substantially around the pipe passage, a cu,tter-pressing jaw mounted on the cutting head and displaceable in a predetermined direction transversely relative to the pipe passage, a cutting disc carried by the cutter-presssing jaw,a; ; screw threaded in said cutter pressing jaw, said screw having a spindle portion extending through said cutting head outwardly of the same, a knob at the outer end of said spindle portion to manually rotate the screw, means to prevent axial displacement of said spindle portion, said body and said cutting head being each composed of two half¯ parts with means to removably secure the respective half-parts together, the half-parts of said head forming each a complementary bore portion for removably receiving the spindle portion of said screw. 13. A manual pipe cutter as defined in claim 12, further including a pair of pipe-engaging rollers carried by said cutting head diametrically opposite to said cutting disc, said rollers extending between the two half-parts of said cutting head and accessible for removal upon separation of said two cutting head half-parts.

Inventors: COURTY, AURELE, Courty, Aurèle
Applicants: COURTY, AURELE
Application year: 1984
Main classification: B23D21
IPC codes: B23D21