US2817898A

US2817898A - Pipe cutters

Info

Publication number: US2817898A
Application number: US637850A
Authority: US
Inventors: Vermette Howard
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-08-24
Filing date: 1957-01-04
Publication date: 1957-12-31
Anticipated expiration: 1974-12-31

Description

Dec. 31, 195.7 H. VERMETTE 2,317,898

PIPE CUTTERS Filed Jan. 4, 1957 3 SheetsSheet l T v I g Dec. 31, 1957 H. VERME'I 'TE PIPE CUTTERS 3 Sheets-Sheet 2 Filed Jan. 4, 1957 IN VEN TOR.

flan/flea VEEMETTE IrraR/YEX H. VERMETTE Dec. 31, 1957 PIPE CUTTERS 3 Sheets-Sheet 3 Filed Jan. 4, 1957 flaw 07 5 0 NM 7 m; M W v/ PIPE CUTTERS Howard Vermette, Hammond, Ind.

Original application August 24, 1956, Serial No. 606,110. Divided and this application January 4, 1957, Serial No. 637,850

9 Claims. (Cl. -102) My invention relates to pipe cutters and similar devices, and this application is a division of my co-pending application Serial No. 606,110, filed August 24, 1956. Y

My invention relates more particularly to pipe, rod or tube cutters of the type commonly used by plumbers and electricians for cutting pipe or tubing on the job, either by hand or with a power driven chuck.

One of the objects of my invention is to provide in mechanism of the type described an improved wheel and roller tube or pipe cutter. Cutters of this type have a tendency to spiral instead of tracking over the first impression of the cutting wheel. Often when a cutter is allowed to spiral, the frame of the tool is permanently bent and the problem is aggravated. My invention incorporates a number of improvements to overcome this diificulty and even provides for realignment if by some unfortunate accident the frame is sprung or bent.

Spiraling is more frequently experienced on larger diameter pipe than on the smaller sizes. This is because of the greater circumference and the greater distance the cutter wheel must travel to re-enter the start of its cut. Three-wheel cutters have divided this distance by three and greatly reduced the possibility of spiraling, but they also cause a burr that makes it diflicult to start a die. When rollers replace two of the wheels, the burr is pressed down and assists in parting the pipe. In my invention, combination rollers and wheels are used in two positions and a cut-off wheel in the third position. The projections on the rollers will not part the pipe because they are only high enough to assist in tracking. This allows the roller to contact the pipe and flatten the burr before final parting is completed.

Another important feature of my invention is the replacement of the commonly used feed screw which is used for advancing the cutter, by a ratchetmechanism. Feed screws are notable for their power loss because of friction, while a ratchet will transmit a favorably high percentage of the power applied. Spiraling is also caused by twisting of the complete tool when the screw handle is turned. a A ratchet or rack and pawl operates in line with rotation and therefore exerts no twisting force that will encourage spiraling.

Another important feature of my invention is the releasing ofthe ratchet for quick adjustment of the tool to fit various pipe sizes within the capacity of 'the tool. The racks and pawls are provided with 21 multiplicity of engaging parts to insure positive action and long service.

A further feature of the invention is the provision of a flat rest to insure accurate alignment of the cutter wheel and guide rollers when the cutter is supported by the re bars commonly provided with power chucks,

Otherobjects and advantages will be more apparent from the following description wherein'reference is had tothe accompanying drawings, upon which:

Fig. 1 is a side elevational viewof the pipe cutter;

Fig. 2;is a cross-sectional view thereof taken on line 2-'-2 of Fig. l;

tes Patent Fig. 3 is a plan view thereof;

Fig. '4 is apers'pective of the ratchet bar and holding dog associated therewith;

Fig. 5 is a fragmentary side elevational view of a modified'form of pipe cutter generally similar to that shown in Fig. 1, the same being provided, however, with a moditied form of ratchet mechanism;

Fig. 6 is a cross-sectional view thereof taken on the line Fi -s; 1

Fig. 7 is a side elevational view of the pawl or holding doglshown in Figs. Sand 6; and

Fig. 8 is a side elevational view of a modified form of pawl or holding dog. 1

In the embodiment of the invention shown in Figs. 1 to 4 inclusive, I have'shown a form of pipe cutter wherein I provide a frame made of two similar plates 101 and I connected by a curved brace member 103 which carries the guide rollers 102 on stub shafts 104 and which is also provided with a bore 105 in each of the walls 101' to support a cros's-rod106; .The back ends of the side walls to'which the'operating handle 126 is connected, the shaft 7 being carried in

side wall portions

128 and 130 of the cutter holder 108. The handle 126 has a raised boss 132 thereon that has a longitudinal bore 134 therein, terminating in a reduced opening'136 in the end wall of the same.

" The bore 134 is adapted to receive a plunger 138 with a reducedend 140 extending through the opening 136. A compression spring'142 surrounds the stem of the plunger 138 and is backed by a'threaded plug 144 to normally hold the, end 140 of the. plunger against a wall 146 on the end of the cutter holder 108.

' 'I mount a pair of ratchets 148 and holding dogs 150 on the sides of the

side walls

128 and 130 of the cutter holder, the same being pivotally mounted upon a pin 152 which extends through a suitable longitudinal bore in the shaft 124. Each of the ratchets has a sloping cam surface 154 reclining against a pin member 156 mounted on the side walls of the cutter holder.

-I also provide a stop cam 160 having a flattened face 162, the cam being mounted for rotation in the

side walls

128 and 130 of the cutter holder and being provided with a knob 164 at oneend for rotating the same when desired. I provide a pin in each of the

side walls

128 and 130 for holding afla't spring 172, the spring being split so that one portionbears against the dog 150 and the other-portion bears against the ratchet 148 to normally hold both the ratchet and holding dog in engagement with the teethof the segmental rack 120.

.With the above described construction, when it is desired-to cut offan end of pipe P, the cutter is placed upon suitable holders and the pivotally mounted cutter holder is moved against the periphery of the pipe. By holding theframe'100 rigid and mounting the handle 126 upon a support bar B, rotation of the pipe by a power chuck willstart a vibration of the cutterlhandle 126 on its pivot against the compression'spring142, thereby tending to permit the ratchetbar'148 to start climbing on the teeth 120a ofthesegmental racks 120', and in this way the cutter wheel 11 0 automatically fed forward through a cutting operation. I Thefratchet bar, as it climbs up on the teeth 120a, carries the holding dogs .150 in such manner that Fatented Dec. 31, 1957 3 the movement will always be forward in a steady cutting operation.

When it is desired to release the ratchet bars from the racks 120, the stop cam 160 may be rotated slightly so that the flattened face 162 underlies the handle 126 and the same can then be swung downwardly through a greater angle toseparate the cutter holder and frame for the reccption of the next piece of work; for a cutting operation.

In the embodiment of the invention shown, in Figs. v5 to 8 inclusive, I provide a frame made of similar plates 101 and connected by a curved brace member 103 which carries the guide rollers 102 on stub shafts 104 and which is also provided with a bore 105 in each of the walls-101 to support a cross-rod 106. The backends of the side walls 101 are formed with segmental racks provided with the teeth 102 formed therein.

I providea cutter holder 108 whichis fastenedto the cross-rod 106 by screw members122, the cutter, holder carrying the cutter roller 110 on a suitable pivot 112 between theside walls 114 and,116 of the same, the side walls being provided with bores 118 to receive the crossrod 106.

The cutter holder 108 also carries. a pivoted shaft 124 to which the operating handle 126 is connected, the shaft being carried in

side wall portions

128 and 130 of the I cutter holder 108. The handle 126 has a, raised boss 132 thereon that has a longitudinal bore 134 therein terminating in a reduced opening 136 in the wall of the same. The bore 134 is adapted to receive a plunger 138 with a reduced end 140 extending through the opening 136. A I

compression spring 142 surrounds the stern of the plunger 138 and is backed by a threaded plug 144 to normally hold the end 140 of the plunger against a wall146 on the end of the cutter holder 108.

l mount a pair of ratchets 148 and the holding dogs 180 on the sides of the

side walls

128 and 130 of the cutter holder, the ratchets 148 being pivotally mounted upon a pin 152 which extends through a longitudinal bore in the shaft 124 and the holding dogs or pawls 180 being mounted upon a pin 182 that extends through the

side walls

128 and 130 of the ,cutter holder 108 below the shaft 124.

Each of the ratchets 148 carries a pin 149, adjacent its toothed lower end, the pin being adapted to engage in a slot 184 in the lower end of the pawl or dog 180. Each of the ratchets 148 has a sloping cam surface 154 normally held against a pin member 156 mounted on the

side walls

128 and 130 of the cutter holder-108. The ratchets 148 are thus held againstthe pin 156 and with their I toothed end 1481: in engagement with the rack teeth 120a of the rack 120 by a portion of a flat spring. member 172 held by a pin in each of the, sidewalls 128 and 130 of the cutter'holder. The spring 172 issplit so that one portion also bears against the pawl or dog to normally hold both the teeth on the ratchetand ,on the holding dog in engagement with the teeth 120a of the segmental rack 120.

In this construction, similar to that shown in Figs. 1 to 4 inclusive, I provide the stop cam 160 having a flattened face 162,'the cam being mounted for rotation in the

side walls

128 and 130 ofthe cutter holder and being provided with a knob 164 atoneend for rotating the same when desired. Fig.8 shows amodified form of the dog or pawl 180 wherein; instead of having an open endslot in the bottom of the, same,.I provide an enlarged elongated slot 186, the slot being sufliciently large so that it. may receive the pin 149 :with suflieient clearance to allow the pawl teeth to pass each;other overthe ratchet, this pawl also being held in yielding engagement with the ratchet teeth by thesplitspringmember 172.

With the above dficribedeonstruetion, when it is desired tocut otf an end of pipe P, the cutter is placed upon suitable holders and the pivotally mounted .cutter holder is moved against the periphery of-the pipe. By holding thetframe 100 rigid andmounting the h'andle 126 upon a support bar B, rotation of the pipe by a power chuck will start a vibration of the cutter handle 126 on its pivot against the compression spring 142, thereby tending to permit the ratchet bar 148 to start climbling on the teeth 120a of the segmental racks 120, and in this way the cutter wheel 110 is automatically fed forward through a cutting operation. The ratchet bar, as it climbs up on the teeth 120a, carries the holding dogs 180 in such manner that the movement will always be forward in a steady cutting operation.

When it is desired to release the ratchet bars from the racks 120, the stop. cam 160 may be rotated slightly so that the flattened face 162 underlies the handle 126 and the same can then be swung downwardly through a greater angle to separate the cutter holder and frame for the reception of the next piece of work for a cutting operation.

In the above description of the modification shown in Figs. 5 to 8 inclusive, the same parts shown in Figs. 1 to 4 have been given the'same numbers, the only parts receiving new numbers being the modified ratchets and holding dogs which are illustrated in this embodiment of the invention.

While I have shown and described a specific embodimentof the invention, it will be apparent to those skilled in the art that changes and modifications may be made in the exact details shown, and I do not wish to be limited in any particular; rather what I desire to secure and protect by Letters Patent of the United States is:

l. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable cutter mounted therein, a segmental rack associated with said holder, a handle pivotally connected to said cutter holder and means associated with said handle for moving said cutter holder forward by contact with said rack.

2. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter'holder pivotally connected thereto, a rotatable cut termounted therein, a segmental rack associated with said holder, a handle pivotally connected to said cutter holder and means associated with said handle for moving said cutter holder forward by contact with said rack, said means comprising a ratchet and holding dog carried by said handle and spring means between said handle and said cutter holder.

3. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable eutter carried by said holder in alignment with said guide rollers, a pair of segmental racks associated with said holder, a handle pivotally connected to said cutter holder and a pair of ratchets and holding dogs-carried by said handlefor moving said cutter forward in a cutting operation.

4. -A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter'- holder pivotally connected thereto, a rotatable cutter carried by said holder in alignment with said guide rollers, a'pair of segmental racks associated with said holder, a handle pivotally connected to said cutter holder and a pair of ratchets and holding dogs carried by said handle for'moving said cutter forward in a cutting operation, a stop cam mounted in said holder below said handle for limiting the pivotal movement of said handle.

5. A pipe cutter comprising a frame having one or moreguide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable cuttercarried by said holder in alignment with said guide rollers, a pair of segmental racks associated with said holder, a handle pivotally connected to said cutter holder and apair of'ratchets and holding dogs carried by said handle for moving said cutter forward in acutting operation, a stop cam mounted in said holder below said handle for limiting the pivotal movement of said handle, said cam rotatable to permit increased pivotal movement of said handle.

6. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable cutter mounted therein, a segmental rack associated with said holder, a handle pivotally connected to said cutter holder and ratchet mechanism between said handle and said cutter holder for moving the same forward.

7. A pipe cutter comprising a frame having pipe guide rollers rotatably mounted therein, a cutter holder pivotally connected to said frame, a rotatable cutter mounted therein, a handle pivotally connected to said cutter holder and means for moving the same forward, said means including a rack positioned on said holder and a yieldably mounted dog member on said handle.

8. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable cutter mounted therein, a segmental rack associated with said holder, a handle pivotally connected to said cutter holder and means associated with said handle for moving said cutter holder forward by contact with said rack, said means comprising a ratchet and holding dog carried by said handle and spring means between said handle and said cutter holder, said cutter holder having a pin for engaging said dog to disengage said dog from said ratchet when desired.

9. A pipe cutter comprising a frame having one or more guide rollers mounted for rotation therein, a cutter holder pivotally connected thereto, a rotatable cutter carried by said holder in alignment with said guide rollers, a pair of segmental racks associated with said holder, a handle pivotally connected to said cutter holder and a pair of ratchets and holding dogs carried by said handle for moving said cutter forward in a cutting operation, a stop cam mounted in said holder below said handle for limiting the pivotal movement of said handle, said cam rotatable to permit increased pivotal movement of said handle, said cutter holder having a pin for engaging said dog to disengage said dog from said ratchet when desired.

No references cited.