U.S. patent application number 11/803762 was filed with the patent office on 2007-09-27 for table saw having a measurement and display system.
Invention is credited to Stephen C. Oberheim.
Application Number | 20070220771 11/803762 |
Document ID | / |
Family ID | 34934980 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070220771 |
Kind Code |
A1 |
Oberheim; Stephen C. |
September 27, 2007 |
Table saw having a measurement and display system
Abstract
A table saw having various embodiments of a measurement and
display system. Several embodiments have at least one fence rail on
which a removable fence is movably supported and comprise an
elongated sensor strip that is located adjacent the fence rail and
a sensing unit that is supported and positioned adjacent to the
sensor strip and is capable of providing an electrical signal to a
display unit that is indicative of the position of the sensor unit
relative to the elongated sensor strip. A processing unit is
operatively connected to the sensing unit and display unit to
provide a digital readout of the position of the sensing unit. A
switch is connected to the processing unit and is adapted to
provide a zero or reference setting position.
Inventors: |
Oberheim; Stephen C.; (Des
Plaines, IL) |
Correspondence
Address: |
GREER, BURNS & CRAIN
300 S WACKER DR
25TH FLOOR
CHICAGO
IL
60606
US
|
Family ID: |
34934980 |
Appl. No.: |
11/803762 |
Filed: |
May 16, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10823270 |
Apr 13, 2004 |
7231858 |
|
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11803762 |
May 16, 2007 |
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Current U.S.
Class: |
33/706 |
Current CPC
Class: |
Y10T 83/727 20150401;
Y10T 83/7684 20150401; B23D 59/001 20130101; Y10T 83/773 20150401;
B27B 27/02 20130101; Y10T 83/856 20150401; Y10T 83/857 20150401;
B23D 47/025 20130101 |
Class at
Publication: |
033/706 |
International
Class: |
B26D 5/40 20060101
B26D005/40 |
Claims
1. A linear measurement and display system for a table saw of the
type which has a removable fence that is laterally adjustable
relative to the blade of the saw along a fence rail located on the
front of the table saw, said system comprising: a sensor strip
positioned generally parallel to the fence rail, said sensor strip
configured to provide digital signals that are indicative of
specific positions along the length thereof; a sensing unit movable
along said sensor strip and operatively connected to the fence,
said sensing unit generating signals indicative of the specific
lateral position of the fence; a switch operatively connected to a
processing unit for establishing a reference position when
activated; a processing unit connected to said sensing unit for
receiving said position indicating signals and for calculating the
distance between said fence and said reference position and for
generating display signals indicative of said calculated distance;
and a display unit electrically connected to said processing unit
configured to receive said display signals and provide a digital
display of said calculated distance.
2. A system as defined in claim 1 wherein said sensor strip is
connected to the fence rail.
3. system as defined in claim 1 further comprising a member
physically connecting said sensing unit, said display unit and said
processing unit together, the fence having a pin for engaging a
slot in said member, whereby the fence is physically coupled to
said sensing unit when the fence is attached to the fence rail.
4. A system as defined in claim 1 wherein said processing unit is
capable of generating display signals that cause said display unit
to display said calculated distance in one of English or metric
units.
5. A system as defined in claim 1 wherein said processing unit is
housed with said sensing unit, said table saw further comprising a
battery for powering said processing unit and said sensing
unit.
6. A system as defined in claim 1 further comprising a display rail
extending parallel to said sensor strip, said display unit being
slidable along said display rail and being mechanically and
electrically connected to said sensing unit and said processing
unit.
7. A system as defined in claim 1 further comprising a table top
extension that abuts said main table top and at least one table
extension rail, said table top extension being connected to the
fence rail, the fence rail being slidably attached to said table
extension rail so that said table top extension can be separated
from said main table top to increase the effective area of the top
of said table saw.
8. A system as defined in claim 6 wherein at least one ribbon
connector electrically connects said sensing unit with said display
unit and said processing unit.
9. A system as defined in claim 3 wherein said switch is mounted
adjacent said display unit.
10. A system as defined in claim 3 further comprising an on/off
switch for controlling power to said processing unit.
11. A system as defined in claim 3 further comprising a switch for
selectively alternating between English and metric units of length.
Description
[0001] This is a divisional of application Ser. No. 10/823, 270,
filed Apr. 13, 2004.
[0002] BACKGROUND OF THE INVENTION
[0003] Table saws of the type which have a circular cutting blade
are well known and have been used by tradesmen and woodworkers for
decades. Because they have a generally flat surface, large and
small boards as well as plywood sheets can be cut to the
appropriate size by typically setting a fence at the appropriate
position to perform a cut along a desired line which is done by
pushing the board or sheet across the tabletop and through the
blade. Typically, the fence is adjustable by sliding along an
elongated rail anchored at opposite ends of the table saw top, with
the fence having a clamping mechanism to lock the fence once it has
been placed in the desired position. Most users, when they know the
width of the desired board will use a tape measure or other measure
to position the fence to obtain the desired width by measuring
between the edge of the blade to the fence. After the fence is in
position, it is locked in place and users typically remeasure the
distance to make sure that they have the fence in the correct
position.
[0004] While the manual measurement and setting of the position of
the fence is the manner in which the fence has been positioned by
most users over the years, in some instances it is highly desirable
to have very accurate measurements which may be difficult depending
upon the type of measuring device is being used. Most tape
measures, for example, do not have accurate measurements beyond a
1/32 of an inch or less. Also, if the fence is moved during other
types of cuts, it is not possible to reset the fence at exactly the
same position that was used for a prior cut without going through
the complete exercise again. If the user does not remember the
prior cut distance, then additional measurements of a work-piece
may be necessary in order to obtain the distance which must then be
used to correctly position the fence.
DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a front view of a first preferred embodiment of a
table saw having a measurement and display system;
[0006] FIG. 2 is a front view of a second preferred embodiment of a
table saw similar to the table saw shown in FIG. 1, but having a
tabletop extension shown in an extended position;
[0007] FIG. 3 is a cross-section taken generally along the line 3-3
of FIG. 2;
[0008] FIG. 4 is a front view of a portion of the table saw shown
in FIGS. 1 and2;
[0009] FIG. 5 is a section taken generally along the line 5-5 of
FIG. 4; and
[0010] FIG. 6 is a front view of a third preferred embodiment
illustrating a display unit having additional functionality
relative to the display unit shown in FIG.4.
[0011] FIG. 7 is a perspective view of an idealized illustration of
a third preferred embodiment of a table saw having a measurement
and display system;
[0012] FIG. 8 is an end view of the embodiment shown in FIG. 7 and
illustrating a mounting bracket in phantom;
[0013] FIG. 9 is an enlarged perspective of a portion of the
embodiment shown in FIG. 7;
[0014] FIG. 10 is a perspective view of an idealized illustration
of a fourth preferred embodiment of a table saw having a
measurement and display system;
[0015] FIG. 11 is a perspective view of an idealized illustration
of a fifth preferred embodiment of a table saw having a measurement
and display system;
[0016] FIG. 12 is a perspective view of an idealized illustration
of a sixth preferred embodiment of a table saw having a measurement
and display system; and
[0017] FIG. 13 is a perspective view of an idealized illustration
of a seventh preferred embodiment of a table saw having a
measurement and display system.
SUMMARY OF THE INVENTION
[0018] A table saw having a measurement and display system has at
least one fence rail on which a removable fence is movably
supported. Several embodiments have an elongated sensor strip
located adjacent the fence rail and a sensing unit that is
supported and positioned adjacent to the sensor strip and is
capable of providing an electrical signal to a display unit that is
indicative of the position of the sensor unit relative to the
elongated sensor strip. A processing unit is operatively connected
to the sensing unit and display unit to provide a digital readout
of the position of the sensing unit. A switch is connected to the
processing unit and is adapted to provide a zero or reference
setting position and this embodiment may include a second switch
for changing between English and metric units.
[0019] A second preferred embodiment includes a table extension
which can be moved to increase the effective size of the table saw
top so that larger work pieces can be supported during cutting. In
this embodiment, the fence rail is connected to an extension rail
so that the fence rail moves with the extension to thereby increase
the range of the sensor strip and sensing unit for providing larger
measurements.
[0020] A third preferred embodiment includes a more sophisticated
display and processor functionality, which, among other things, can
display English units in decimal or fractions as well as store and
recall important distance measurement positions.
[0021] A fourth preferred embodiment includes a mounting mechanism
that enables a relatively short and inexpensive sensor strip to be
selectively positioned to increase the range of measurement of a
fence along the width of the table saw and to adjust the
measurement as a result of the position of the sensor strip.
[0022] A fifth preferred embodiment operates with a sensing rail
that is located on the front of the table saw, but has all other
operative elements mounted on the fence.
[0023] Sixth and seventh preferred embodiments operate with a
string or tape position transducer device that interconnects a
stationary location on the table saw and the movable fence.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] A first embodiment of a table saw of the present invention
is shown in FIGS. 1, 2 and 3 and illustrates a table saw, indicated
generally at 10, of the type which is configured to be supported by
a table 12 or other support structure or frame having legs. It
should be understood that the table saw 10 could be of the type
which has its own support stand and may be more permanent rather
than the one illustrated which is often referred to as a portable
saw. The saw 10 has a base 14 in which the saw motor (not shown) is
located with the motor driving a blade 16, the height of which can
be adjusted by conventional adjustment means (not shown) and which
can also be angularly adjustable by an assembly that includes a
wheel 18.
[0025] The saw 10 has a main tabletop 20, a tabletop extension 22
and an adjustable fence, indicated generally at 24, that has a
handle 26 that can be raised and lowered to lock the fence in a
desired lateral position relative to the blade. The fence has a
base portion 28 that is slidably adjustable along a fence rail 30
that extends substantially the full width of the saw. While not
illustrated, the fence preferably has its opposite end configured
to ride on another fence rail which facilitate its sliding lateral
movement, i.e., left and right as shown in FIG. 1.
[0026] The table saw 10 illustrated in FIG. 1 is shown with the
extension 22 in an unextended position whereas in FIG. 2, the
extension 22 is extended outwardly to the right. This is achieved
by a locking knob 32 being loosened so that the fence rail 30,
which is supported by an extension rail 34 can be moved along the
extension rail 34. It should be understood that the fence 24 in
FIG. 2 has been moved relative to its position in FIG. 1 to more
clearly illustrate the manner in which the extension 22 moves
relative to the extension rail 34. The configuration which
particularly illustrates the interoperability of the fence rail 30
and the extension rail 34 is shown in FIG. 3, with the extension
rail 34 having a base portion 36 that is connected to the main top
20 by bolts 38, screws, weldments or the like, with short
transverse segment 40 extending away from the base 36 and then
outwardly to form flanges 42 and transverse end segments 44. The
configuration provides a narrow space 46 between the top 20 and the
extension rail 34 so that the fence rail 30 can easily slide
relative to the extension rail 34 but be held captive so that any
appreciable vertical and horizontal movement between the two
components is prevented. An end cap 48 made of plastic or
plastic-like material is preferably provided at opposite ends of
the fence rail 30 and is preferably a resilient material that can
be snap-fit into the interior of therail30.
[0027] As best shown in FIGS. 1, 2 and 3, a display rail 50 is
positioned below the fence rail 30 and is attached thereto by two
brackets 52 which are located at opposite ends of the fence rail
30. The brackets 52 have a front upper flange 54 upon which a
spacer 56 is positioned with the flange 54 and spacer being
connected to the fence rail 30 by a bolt 58 and nut 60, screws,
weldment or other equivalent attachment means. The opposite ends of
the display rail 50 are attached to the bracket 52 by suitable
screws, adhesive, bolts or the like (not shown). The display rail
has a base portion 62 as well as transverse end portions 64 and
return flanges 66 which define a recess in which a display unit,
indicated generally at 70, can be inserted and be held captive so
that vertical and horizontal movement is prevented but which will
permit sliding lateral movement, i.e., left or right as shown in
FIGS. 1 and 2.
[0028] On the backside of the bracket 52 a sensor strip 72 is
attached by screws, bolts, adhesive or the like. A sensor strip 74
is attached to the sensor strip 72, preferably using an adhesive
material. While the cross section of the sensor strip 74 is shown
in FIG. 3 and is therefore illustrated to be located at the left
end of the sensor strip 72. In actuality, the length of the sensor
strip 74 is preferably within the range of about 15 to about 25
inches and preferably about 20 inches with the left end of the
sensor strip being approximately coextensive with the blade and
extending to the right end thereof as shown in FIG. 1. In this
regard, the drawing is technically in error, but does generally
show the relative size and configuration of the strip relative to
the sensor strip. It should also be understood that when the
extension 22 is moved to the right as shown in FIG. 2, the left end
of the sensor strip 74 will move to the right of the blade 16.
[0029] It should be understood that another preferred embodiment of
the table saw may not include the extension 22 and therefore would
not need to have the extension rail 34, in which case the fence
rail 30 would be attached directly to the table top 20 or other
structure associated with the frame because the fence rail 30 would
not move laterally.
[0030] As shown in FIG. 4, the display unit 70 has an electronic
display 76 that is mounted to a display block 78 that is preferably
a unitary piece of aluminum or other metal that has an angled front
face 80 with a suitable recess (not shown) in which the display 76
can be inserted, with the ends extending further outwardly so as to
provide some protection against damage during use. The right end of
the block 78 has a vertically oriented slot 82 that has a width
that is closely matched to the outside diameter of a pin 84 that is
attached to the fence base 28. The pin 84 therefore causes the
display unit 70 to move with the fence as it is laterally adjusted
during use. Since the pin 84 merely rides in the slot 82 of the
block 78, the fence 24 can be lifted without difficulty from the
table saw. However, when it is lowered into place so that the fence
base 28 rides on the fence rail 30, the pin 84 is closely fits in
the slot 82. The display 76 has a ribbon connector 86 that extends
to a sensor 88 that is secured to the display block 78 by a bolt
90, although adhesive or other attachment means may be used. The
sensor 88 is configured relative to the sensor strip 72 so that the
necessary tolerances between the two are maintained as the sensor
88 is moved along the sensor strip.
[0031] A sensor 88 is secured to the display block 78 by bolts 90
and the sensor strip 72 has copper pads along its length that are
positioned to provide a changing capacitance that is sensed by the
sensor element 58 and which can thereby provide accurate
measurement of incremental positions along the length of the rail.
In this regard, it is preferred that the sensor strip 72 and sensor
88 be similar to those that are presently used in commercially
available digital calipers. Other linear sensor technologies based
on inductance, magnetostrictive effects or resistive elements can
also be used.
[0032] The display 76 has a front panel with a pushbutton switch 96
which is a zero set switch and a switch 98 which toggles between
English and metric systems in the display window 100. The display
window is preferably a LCD display which has four integers 102 and
a decimal 106 as well as a field 108 indicating inches or
millimeters.
[0033] During operation, when the fence 24 is positioned abutting
the blade 16, for example, an operator can depress the zero set
pushbutton 96 which will result in the display window readout
indicating a zero position. That having been done, if the user
wants to position the fence so that a six inch wide cut of a work
piece is desired, the fence 24 can be moved to the right until the
display indicates that the fence has been moved 6.00 inches (or the
appropriate millimeter conversion) at which time the user can lock
the fence 24 in position by moving the lock handle 26 downwardly in
the illustrated embodiment.
[0034] If during the locking of the fence, the fence moves either
left or right as shown in FIG. 4, the display 76 will so indicate,
which enables the user to unlock the fence and correctly position
it until the exact distance of six inches is locked into position.
If the sensing strip/sensor has a 1/100 inch or 1/10 millimeter
degree of accuracy, the fence can be positioned to that degree of
accuracy.
[0035] Turning to another preferred embodiment of the present
invention and referring to FIG. 6, a display 110 is shown which has
additional functionality. More particularly, the display has a
pushbutton 112 which toggles between English and metric units and
has a six integer display with two decimal points and a slash
indicator which enables English units to be displayed in hundredths
or in fractions and metric units to be displayed in thousandths or
ten thousandths of an inch. Additionally, the display includes a
zero pushbutton 114 as well as a store pushbutton 116 and a recall
pushbutton 118 as well as an offset pushbutton 120. The display is
also operable to set and utilize a DADO blade offset as well as a
fence offset in either 1/16 or 1/32 increments which enables a user
to appropriately set the position.
[0036] Another embodiment of the present invention is shown in
FIGS. 7-9 which comprises a table saw having a table top 20 that
has an opening through which a saw blade 16 is positioned. A fence
indicated generally at 24' has a base 28' that has a recess which
cooperatively engages a fence rail 130 and is configured to slide
along the fence rail 130 and be clamped to it. While the
diagrammatic illustration of the fence 24 shown in FIGS. 7, 8 and 9
is greatly simplified, it should be understood that a clamping or
locking mechanism is preferably provided as is known to those of
ordinary skill in the art.
[0037] The fence rail 130 is attached to the table 20 by suitable
bolts or the like that are located inside a pair of standoffs 131
which appropriately space the fence rail from the front edge of the
tabletop 20. A display 70' is mounted on a block extrusion 132 that
is coupled to the base 28' of the fence 24'. The block extrusion
132 has an angled front portion 134 to which the display 70' is
attached and the top of the front portion 134 has a forwardly
directed flange 136 that is substantially parallel to the base 28'
of the fence. A pin 138 mounted to the base 28' extends into a slot
in the flange 136 with the width of the slot being substantially
equal to the outside diameter of the pin 138 so that movement of
the fence along the sensing rail 130 will also move the block
extrusion 132.
[0038] The block extrusion 132 also has a middle portion 140 that
extends in the rearward direction and carries a T-shaped cross
section 142 as well as a rearward extension 144 that is vertically
oriented and provides a surface to which a sensing unit 146 is
mounted. A flexible ribbon cable similar to the ribbon connector 86
shown in FIG. 5 interconnects the sensing unit 146 to the display
module 70'.
[0039] The sensing unit has an opening 148 through which a sensing
rail 150 is positioned, the sensing rail being mounted at opposite
ends to an extension rail 152. The extension rail 152 has a pair of
rearward extensions 154 which have transverse extensions 156 that
are directed toward each other and encompass the T-shape portion
142 of the block extrusion. The block extrusion 132 is supported by
and can move relative to the extension rail 152 enabling the
sensing unit 146 to provide a measurement of the position along the
sensing rail 150 and provide a digital output of the position.
Importantly, the length of the extension rail 152 is slightly
greater than the length of the sensing rail 150 and a pair of
brackets at each end attach the extension rail 152 to the sensing
rail 150. The extension rail is itself supported and held captive
in the fence rail 130 which has an inclined inside front portion
160 that has a lower angled flange 162 and an upper flange 164
which surround the extension rail 152. The extension rail 152 is
movable relative to the fence rail 130 by a distance that is
approximately equal to the length of the slot 166.
[0040] As is best shown in FIG. 7, the fence rail 130 has an
elongated slot 166 through which a threaded bolt 168 is located,
with the bolt having a knob 170 that can be rotated to tighten or
loosen the bolt 168 which is threaded into an opening in the
extension rail 152. When it is loosened, the extension rail may be
moved so that the knob will be moved along the length of the slot
166 which is approximately 12 inches in the illustrated embodiment.
This means that the length of the sensing rail 150 is approximately
the same length, with the width of the tabletop 20 being
approximately two feet in total. However, it should be understood
that a shorter or longer slot may be provided.
[0041] When the knob 170 is loosened, the extension rail 152 can be
moved along the slot 166 from the position that is shown to the far
left end as shown in FIG. 7. Indicia such as a green dot 176 near
the left end and a red dot 178 on the right end are provided
together with green and red switches 176 and 178, respectively,
which the operator can press depending upon which end the knob 170
is positioned. By so doing, the processing means in the display
module 70' can automatically compensate for the changed position
relative to the blade 16. In this way, a 12 inch long sensing rail
can be used to effectively measure across the entire width of the
table. This is advantageous because the cost of sensing systems and
particularly sensing rails dramatically increases with increased
lengths.
[0042] A fifth preferred embodiment is shown in a simplified
diagrammatic fashion in FIGS. 10 and 11, and has a removable fence
24'' with a base 28'' that is configured to be supported on a fence
rail 190 that is preferably an extrusion with a flat top and a
front recess 192 which is configured to receive a sensing rail 194
that is attached to the rail by suitable means such as an adhesive,
mechanical clips, screws, or the like. The fence rail 190 is
attached to the saw table top 20 by two or more bolts 196 which
extend from the fence rail 190 to the top 20 through standoffs 198
as shown in FIG. 11.
[0043] As is shown in FIG. 10, the sensing rail 194 extends
substantially across the entire front of the table saw. The fence
24'' has a mounting bracket 200 attached thereto for providing a
support for a display module 70'' that may have structure and
functionality that is similar to the structure of the display
module 70 or 76. A sensor unit 202 is mounted to the bottom 28'' of
the fence 24'' and is positioned adjacent the sensor strip 194. An
advantage of this embodiment is that all components except the
sensor strip 194 are mounted to the fence 24'', and no wires
between the sensor unit 202 and the display module 70'' need to be
exposed and therefore susceptible to damage during use. The fence
can be easily removed from the table saw without the necessity of
disengaging any parts, unplugging cables or other
inconveniences.
[0044] A sixth preferred embodiment is shown in FIG. 12 and has a
rotational position transducer unit 210 that is mounted to the
table saw 212 and has a flexible tape 214 extending from the unit
that extends to and is connected to a bracket 216 to which a
display module 218 is attached. While a tape 214 is shown, it
should be appreciated that a cable or string type of unit is
commercially available and may be used. Regardless, the tape 214 is
held under tension by a spring mechanism in the position transducer
unit 210 and the unit generates an electrical signal that is
indicative of the amount of tape or string that is pulled out of
the unit 210. The bracket 216 is supported by and slides along a
bottom portion 220 of an extrusion 222 that extends along the front
of the saw 212. The extrusion has a recess 224 in which a fence 226
can slide with fence having a base portion 228 that has a
downwardly extending pin 230 that can fit within a hole in the
bracket 216. This enables the fence 226 to be removably coupled to
the bracket 216. While not shown, the fence preferably has a
locking mechanism to hold the fence in the desired position when
that is determined. Power for operating the unit 210 can be
provided by an AC source through cords 232, 234 and transformer
236. Alternatively, a battery may be used if desired.
[0045] The tape 214 can be attached to either the bracket 216 or
the display unit 218 as desired. As the fence and bracket 216 are
moved along the front of the table saw 212, the tape 214 is wound
and unwound from the unit and an electrical signal is generated and
is communicated to the display unit 218. In this embodiment, the
communication is preferably accomplished by an infrared transmitter
in the unit 210 and an infrared receiver in or adjacent to the
display unit 218. Other types of communication can be used as
desired. Also in this embodiment, a zero button is used to
calibrate the position of the fence at a zero position relative to
the blade as has been previously described with regard to other
embodiments, enabling the distance from the fence 226 to the blade
of the saw to be displayed as the fence 226 is moved away from the
blade the desired distance. An advantage of this embodiment is that
the incremental cost for increased distances is significantly lower
than for many other types of sensing strips or rails.
[0046] A seventh embodiment is shown in FIG. 13 and is similar to
the embodiment of FIG. 12, except that a rotational position
transducer unit is located within a display unit module 240 has a
fence 242 mounted to it. While not shown, the fence 242 is
preferably removable from the module 240 and a locking mechanism is
either associated with the fence 242 or the module 240. A tape 244
extends from the module 240 and is attached to a bracket 246 or the
like that is attached to the table saw. This embodiment has an
extrusion 248 that is similar to the extrusion 222 of FIG. 12 in
that it has a lower portion 250 on which a bracket 252 is slidably
attached. The bracket 252 is attached to and carries the display
module 240. The operation of this embodiment is substantially
similar to the embodiment shown in FIG. 12, but has the advantage
that the position transducer unit is directly connected to the
display unit and no independent communication capability is
required.
[0047] With regard to all of the embodiments described above, the
sensing unit and sensor strip may have copper pads along its length
that are positioned to provide a changing capacitance that is
sensed by the sensor unit and which can thereby provide accurate
measurement of incremental positions along the length of the rail.
In this regard, it is preferred that the sensor strip and sensor
element be similar to those that are presently used in commercially
available digital calipers. However, other linear sensor
technologies based on inductance, magnetostrictive effects,
resistive elements or optical encoded techniques can also be used
without departing from the spirit and scope of the invention.
[0048] While various embodiments of the present invention have been
shown and described, it should be understood that other
modifications, substitutions and alternatives are apparent to one
of ordinary skill in the art. Such modifications, substitutions and
alternatives can be made without departing from the spirit and
scope of the invention, which should be determined from the
appended claims.
[0049] Various features of the invention are set forth in the
following claims.
* * * * *