Device for cutting soil sampling tubing

A device for longitudinally cutting tubing is comprised of a block presenting an engaging surface for receiving tubing, blades and protective guards both coupled to the block and both extending beyond the engaging surface, and a handle coupled to the block. When cutting tubing, the device receives the tubing so that each of the blades cuts at an angle less than 90 degrees with respect to the tangent line of the tubing at the point where each contacts the tubing. This device may be used in a method for cutting tubing comprised of securing a section of tubing, receiving the tubing with the engaging surface of the device, contacting an end of the tubing with at least one blade wherein the blade is positioned at an angle less than 90 degrees with respect to the tangent line of the tubing at the point where the blade contacts the tubing, and cutting the tubing by pulling the block longitudinally along the tubing. This device and method present an easier way for longitudinally cutting tubing and allow multiple cuts to be made simultaneously.

BACKGROUND OF THE INVENTION 
The present invention relates to a device and method for cutting tubing. 
More specifically, this device and method present an easier way for 
longitudinally cutting tubing and allow multiple cuts to be made 
simultaneously. 
Soil sampling has become important in a variety of fields, such as site 
inspections for soil strata determinations or environmental factors. It is 
often desirable to analyze the soil's composition at various depths. In 
analyzing soil, soil samplers are used to collect soil from the subsurface 
of the ground. Several of the soil samplers on the market today use a 
polymer liner or tubing within the soil sampler to hold the soil once it 
has been sampled from the subsurface. In these devices, soil samples are 
then removed from the tubing by making one or more longitudinal cuts in 
the tubing. This allows the soil to be sub-sampled or removed from the 
tubing in small amounts so that nothing is lost. 
The industry presently relies upon simple utility knives to cut this 
tubing. However, using utility knives is inefficient and at times unsafe. 
In addition to being difficult to cut tubing with simple utility knives, 
multiple cuts sometimes must be made before a section of the tubing may be 
removed, allowing the soil to be sub-sampled. 
A cutting device has been proposed which has a single blade that cuts 
perpendicular to the tangent line of the tubing at the point where the 
blade contacts the tubing. Such a device is unsuccessful because as the 
tubing is cut, residual stresses are relieved which result in the tubing 
collapsing slightly. This causes a binding action against the blade and 
makes it difficult to pull the blade through the tubing. It is especially 
difficult to cut in a straight line with such a cutting device. In 
addition, in order to make multiple longitudinal cuts, each cut must be 
made separately, and the tubing must then be rotated before an additional 
cut is made. 
Thus, a cutting tool is needed which is able to safely and easily cut 
tubing. Further, a device is needed that will simply, efficiently and 
economically perform this function. A device is also needed which is able 
to make at least two parallel longitudinal cuts in a section of tubing 
simultaneously with little effort. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a simple, efficient, 
and economical device and method for cutting tubing. 
Another object of the present invention is to provide a device which cuts 
tubing easily by cutting the tubing at an angle which is less than 90 
degrees with respect to the tangent line of the tubing at the point where 
the blade of the device contacts the tubing and a method for using this 
device. 
It is a further object of the present invention to provide a device for 
cutting tubing which makes at least two cuts simultaneously and a method 
for using this device. 
It is another object of the present invention to provide a device for 
cutting tubing which safely shields the operator from the blade of the 
device while cutting the tubing and a method for using this device. 
Another object of this invention is to provide a device which cuts an 
entire longitudinal section from the tubing in a single motion and a 
method for using this device. 
According to the present invention, the foregoing and other objects are 
achieved by a device for longitudinally cutting tubing comprised of a 
block presenting an engaging surface for receiving tubing, blades and 
protective guards both coupled to the block and both extending beyond the 
engaging surface, and a handle coupled to the block. When cutting tubing, 
the device receives the tubing so that each of the blades cuts at an angle 
less than 90 degrees with respect to the tangent line of the tubing at the 
point where each contacts the tubing. The present invention further 
includes a method for cutting tubing using the above-described device 
comprised of securing a section of tubing, receiving the tubing with the 
engaging surface of the device, contacting an end of the tubing with at 
least one blade wherein this blade is positioned at an angle less than 90 
degrees with respect to the tangent line of the tubing at the point where 
the blade contacts the tubing, and cutting the tubing by pulling the block 
longitudinally along the tubing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
A device for cutting tubing embodying the principles of this invention is 
broadly designated in the drawings by reference numeral 20 and is shown in 
its entirety in FIG. 1, FIG. 2, and FIG. 5. Device 20 is primarily 
comprised of a block 22, a handle 24, blades 26, and protective guards 28. 
Block 22 has an end 22a, sides 22b and 22c, and a concave engaging surface 
22d opposite of end 22a. 
Handle 24 is coupled to a threaded fastener 30, as shown in FIG. 1. 
Threaded fastener 30 is received by end 22a and secures handle 24 to block 
22. Sides 22b and 22c have indentations 23 which receive blades 26, as 
shown in FIG. 1 and FIG. 4. Protective guards 28 are placed over blades 26 
and are secured to sides 22b and 22c by screws 32. Relief area 29, shown 
in FIG. 2 and FIG. 3, is defined between protective guards 28 and blades 
26. Concave engaging surface 22d receives cylindrical tubing 34 which may 
contain soil 36, as shown in FIG. 2 and FIG. 5. 
Preferably, cylindrical tubing 34 is placed on a V-shaped holding structure 
38 and secured to structure 38 by J-shaped projection 40 and projection 42 
by placing an edge of cylindrical tubing 34 underneath J-shaped projection 
40, as shown in FIG. 6 and FIG. 7. Also attached to holding structure 38 
is surface-edge brace 44, shown in FIG. 5 and FIG. 6, which is coupled to 
the end of structure 38 by welding 46. Vise receiver 48 is coupled 
underneath structure 38 and is also shown in FIG. 5. 
Tubing 34 may be secured manually or by a holding structure before it is 
cut. Preferably, tubing 34 is secured by holding structure 38. Holding 
structure 38 may be V-shaped, semi-circular, rectangular or any other 
shape which prevents tubing 34 from rolling. Projections 40 and 42 prevent 
tubing 34 from moving along the axis of the tubing. Specifically, one edge 
of tubing 34 is placed underneath J-shaped projection 40. Then, projection 
42 keeps the other end of tubing 34 from moving and secures tubing 34 
under J-shaped projection 40. Preferably, holding structure 38 is secured 
so as to be immobile. Specifically, it may be secured by a vise clamped to 
vise receiver 48. Alternatively, a surface-edge brace 44 may be coupled to 
one end of holding structure 38. Brace 44 fits over the edge of a surface 
such as a table or workbench, and tubing 34 is cut by pulling device 20 
away from brace 44. The pressure from pulling device 20 keeps brace 44 
secured to the surface edge. Structure 38 may include both a vise receiver 
48 and a surface-edge brace 44 so that it may be secured in various ways. 
Device 20 may have one blade, two blades or a plurality of blades. 
Preferably, device 20 has two blades 26 which are coupled to sides 22b and 
22c of block 22 and have hook-shaped cutting edges 26a. Most preferably, 
each of blades 26 has two hook-shaped cutting edges 26a, as shown in FIG. 
1, allowing blade 26 to simply be rotated rather than replaced if one 
cutting edge 26a becomes dull. As shown in FIG. 3, each cutting edge 26a 
extends beyond concave engaging surface 22d of block 22 and is positioned 
to cut tubing at an angle .varies. less than 90 degrees with respect to 
the tangent line T of the tubing at the point where each blade contacts 
the tubing. Preferably, each blade 26 is positioned to cut at 
approximately a 60 degree angle. The existence of an angled cutting 
approach rather than a perpendicular approach is critical. Forces from the 
residual stresses of a section of tubing act against the blades when 
cutting the tubing. However, such forces seem to have less of a pinching 
or binding effect on blades which cut at angles less than 90 degrees as 
compared to blades which cut perpendicular to the tangent line of the 
tubing. 
Block 22 can be any shape so long as blades 26 are positioned to cut at the 
desired angle. Preferably, surface 22d of block 22 is an engaging surface 
for receiving cylindrical tubing. Most preferably, it is a concave 
engaging surface. 
Protective guards 28 are coupled to block 22. Part of each protective guard 
28 extends beyond surface 22d and acts to shield the operator using device 
20 from blade 26. This is a safety feature of the present invention. 
Preferably, protective guards 28 frictionally secure blades 26 to block 22 
by pinching or holding blades 26 in indentations 23 of sides 22b and 22c. 
As blades 26 are pulled through tubing 34, it is displaced outwardly. 
Thus, preferably, protective guards 28 are configured to define a relief 
area 29 between blade 26 and protective guards 28, as shown in FIG. 3, so 
that the displaced tubing may expand outwardly without any restrictions. 
Specifically, protective guards 28 are configured so that the part 28a of 
the protective guard which extends beyond surface 22d is narrower in width 
than the part 28b which is coupled to side 22b or 22c. Such a 
configuration enables a space 29 to be defined between the parts of each 
blade and each protective guard which extend beyond surface 22d. This 
space 29 acts as a relief area as tubing 34 is cut. 
Device 20 may be a hand-held device if block 22 is coupled with a handle or 
multiple handles. Handle 24 may be coupled to any side of block 22 so long 
as it provides leverage to pull block 22. Preferably, handle 24 is coupled 
to end 22a. Furthermore, handle 24 may be coupled to block 22 in a variety 
of angles depending upon the leverage which the operator needs. For 
instance, it may be attached to give the operator more pulling force when 
cutting tubing with greater wall thickness. 
Holding structure 38 and device 20 may be made in various sizes to 
accommodate cutting of tubing with various diameters. Preferably, device 
20 is used to cut pliable tubing such as polymer tubing, plastic tubing or 
rubber tubing. Preferably, block 22 and blade guard 28 are comprised of 
aluminum, handle 24 is comprised of plastic, and blade 26 is comprised of 
a suitable metal such as steel. 
In operation, after tubing 34 is secured, cutting edges 26a of device 20 
are hooked over an end of a section of tubing 34. Device 20 is then pulled 
so as to make longitudinal cuts in the tubing. Once two longitudinal cuts 
are made, a section of tubing may be removed so as to create a space. This 
space allows one access to the core of the tubing. If soil is in the 
tubing, sub-samples of soil may be removed along this open section. 
From the foregoing, it will be seen that this invention is one well-adapted 
to attain all the ends and objects hereinabove set forth together with 
other advantages which are obvious and which are inherent to the 
structure. It will be understood that certain features and subcombinations 
are of utility and may be employed without reference to other features and 
subcombinations. This is contemplated by and is within the scope of the 
claims. Since many possible embodiments may be made of the invention 
without departing from the scope thereof, it is to be understood that all 
matter herein set forth or shown in the accompanying drawings is to be 
interpreted as illustrative and not in a limiting sense.