On 03/11/2010 06:19 PM, zzzzzzzzzz wrote:

Reading the patent, he certainly *has* sealed off any competing technology.
The amazing thing, is that he seems to have painted himself into the table saw
corner unnecessarily.

I don't think he has...in general the preamble of a patent claim is not
considered a legally limiting constraint. But they're definitely
originally aimed at woodworking equipment.

Chris

On 03/11/2010 06:49 PM, Chris Friesen wrote:
On 03/11/2010 06:12 PM, zzzzzzzzzz wrote:

Have you read the patent claims?

"1. A table saw comprising: a frame structure with a generally flat work
surface; a rotatable circular blade mounted on an arbor and being adapted
to have at least a portion of said blade extending above the flat work
surface in position to cut a work piece; a drive motor with an output shaft
mounted to the frame structure for powering the saw blade; a sensing
mechanism for generating at least a first actuation signal responsive to
predetermined sensed characteristics relating to the existence and/or
movement of a person in close proximity thereto; a retracting mechanism
located beneath said work surface for rapidly moving the blade downwardly
below the work surface responsive to said first actuation signal being
received.

Just to clarify, the patent you're quoting from isn't actually a Sawstop
patent.

The main sawstop patents are 20020069734 and 20020170399.

Sorry, my bad. Those are applications. Gass' patents are below. The
main sawstop patents are the first three.

US7617752 - Contact detection system for power equipment - 11/17/2009
A woodworking machine having one or more dangerous portions is
disclosed. The machine also includes a safety system configured to
detect accidental contact between a person and at least one of the
dangerous portions by electrically coupling a signal to the person's
body, and detecting if the signal becomes coupled to the dangerous portion.

US7600455 - Logic control for fast-acting safety system - 10/13/2009
Woodworking machines including cutting tools and motors adapted to drive
the cutting tools are disclosed. The machines also include a detection
system adapted to detect a dangerous condition between the cutting tool
and a person, and a reaction system adapted to perform a specified
action upon detection of the dangerous condition. The machines further
include a control system adapted to test the operability of at least a
portion of the detection system and/or the reaction system. The control
system is adapted to disable the motor if the tested portion is inoperable.

US20090236012 - Detection systems for power equipment - 09/24/2009
Methods to detect when a human body contacts a predetermined portion of
a machine are disclosed. The methods distinguish contact with a person
from contact with other materials. The methods are particularly
applicable in woodworking equipment such as table saws to distinguish
contact between a person and the blade of the saw from contact between
the blade and wet or green wood. The methods and woodworking equipment
may include predictive blade stop algorithms that prevent unnecessary
activations of a safety brake during coast down of a blade and continued
protection in the event a main power switch is turned off.

US20090293692 - Table saw throat plates and table saws including the
same - 12/03/2009
Throat plates for table saws and table saws including the same are
disclosed. In some embodiments, the throat plates and/or saws include at
least one securement mechanism adapted to secure and prevent inadvertent
removal of the throat plate from the throat of the saw. In some
embodiments, at least one of the securement mechanisms also provides a
height adjustment mechanism and/or prevents vertical removal of the
throat plate. In some embodiments, the throat plate includes an
accessory mounting port that provides a portal for accessories,
including safety accessories, to extend through the plate from beneath
the table of the saw. In some embodiments, the port extends from the
plate's outer perimeter to divide the plate's rear end portion into a
pair of spaced-apart members. In some embodiments, these members are
independently secured to the table saw and retained apart from each
other by one or more of the securement mechanisms.

US7621205 - Band saw with safety system - 11/24/2009
A band saw including a frame, at least two, spaced apart, rotatable
wheels supported by the frame, a blade looped around the wheels, where
rotation of at least one wheel causes the blade to move around the
wheels, a detection system adapted to detect a dangerous condition
between a person and the blade, and a reaction system configured to
engage and stop the blade within 10 milliseconds after detection of the
dangerous condition is disclosed. The reaction system may be configured
to cut and grip the blade.


Chris

On Thu, 11 Mar 2010 18:56:14 -0600, Chris Friesen
wrote:

On 03/11/2010 06:19 PM, zzzzzzzzzz wrote:

Reading the patent, he certainly *has* sealed off any competing technology.
The amazing thing, is that he seems to have painted himself into the table saw
corner unnecessarily.

I don't think he has...in general the preamble of a patent claim is not
considered a legally limiting constraint. But they're definitely
originally aimed at woodworking equipment.

That wasn't a "preamble". It was the first claim; the independent one.

I'll look up the other patents you cited later.

zzzzzzzzzz wrote:


Reading the patent, he certainly *has* sealed off any competing
technology. The amazing thing, is that he seems to have painted
himself into the table saw corner unnecessarily.

I may find myself in the position of having to retract statements I had
previously made. Apparently, like yourself, my recollection of his patent
was faded and some of the things that have been posted today are challenging
that recollection. I do agree with you that for all of his cleverness in
being properly broad, he certainly did seem to miss-fire on the table saw
aspect of this patent.

--

-Mike-

"Chris Friesen" wrote in message
el...
On 03/11/2010 06:49 PM, Chris Friesen wrote:
On 03/11/2010 06:12 PM, zzzzzzzzzz wrote:

Have you read the patent claims?

"1. A table saw comprising: a frame structure with a generally flat
work
surface; a rotatable circular blade mounted on an arbor and being
adapted
to have at least a portion of said blade extending above the flat
work
surface in position to cut a work piece; a drive motor with an output
shaft
mounted to the frame structure for powering the saw blade; a sensing
mechanism for generating at least a first actuation signal responsive
to
predetermined sensed characteristics relating to the existence and/or
movement of a person in close proximity thereto; a retracting
mechanism
located beneath said work surface for rapidly moving the blade
downwardly
below the work surface responsive to said first actuation signal
being
received.

Just to clarify, the patent you're quoting from isn't actually a Sawstop
patent.

The main sawstop patents are 20020069734 and 20020170399.

Sorry, my bad. Those are applications. Gass' patents are below. The
main sawstop patents are the first three.

US7617752 - Contact detection system for power equipment - 11/17/2009
A woodworking machine having one or more dangerous portions is
disclosed. The machine also includes a safety system configured to
detect accidental contact between a person and at least one of the
dangerous portions by electrically coupling a signal to the person's
body,

How is That done? Anyone know?

and detecting if the signal becomes coupled to the dangerous portion.

wrote in message
...
On Thu, 11 Mar 2010 17:00:00 -0600, (Robert
Bonomi) wrote:

In article ,
Mike Marlow wrote:
wrote:

Again - you can only patent a method.

Bull****.

So - are you suggesting you can patent the laws of physics?

Patents rarely specify the precise methodology employed to accomplish an
end.

They claim rights to "a method for .." accomplishing something.

If there _is_ existing competing technology, they have to spell out what
is 'different' about their approach -- that was *NOT* included in the
'a method for ..' claims of the prior patent(s).

If there is *NO* existing competing technology, and you have competently
drawn patent claims, the claim is for 'a method ...' doing the heretofore
impossible. citing the inventor's implementation only as one example of
the claim. In _that_ situation, *any*other* approach to solving the same
problem is simply a different means of doing the _same_thing_, and, as
such,
runs afoul of the original holder's patent that covers the basic idea of
doing _that_ thing.

A major goal of drafting patents is to make the claims as _broad_ and
_all-
encompassing_ as possible.

SawStop's patent(s), by 'virtue' of being the _first_of_its_kind_ are
very broad in scope. It will be 'difficult' (to put it mildly) to build
a competing technology that does _not_ involve: (1) 'a method for...'
detecting the approach of human anatomy to the blade, and/or (b) 'a method
for ...' removing the blade from potential contact.

Exactly right.

Read up on patents. There is nothing
at all stopping another company from coming up with a similar, or a
different approach.

The patent is on the detection of the digit. There are only so many
ways to detect the presence of the digit before it comes in contact
with the works. That's the physics. There isn't another good way and
if the patent attorney had any sense (it was his idea) he'd close off
all other avenues, as well.

He can patent the detection method only to the point of the device
design.
He can't patent the use of capacitance though.

WRONG.

If capacitance has never been used for that purpose previously, he _CAN_
patent 'the use of capacitance for that purpose'.

In fact, he's patented the use if *any* sensor for this purpose.


Prior Art: There exists all manner of machinery with sensors to keep human
appendages out of harms way.

zzzzzzzzzz wrote:


Breaking the blade, if done in the right place, might work. Baring
that, a wrench in the gears would do a lot. Remember, the tool
doesn't have to survive.



Well..... you're close Keith. How about "braking the blade", rather than
"breaking the blade"? Forcing an instant reversal of the motor direction to
stop the blade? Or clamping a brake on the pulley or on the arbor.

--

-Mike-

On Mar 12, 6:11*am, "Mike Marlow"
wrote:
wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. ;-) My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

On Mar 12, 9:07*am, " wrote:
On Mar 12, 6:11*am, "Mike Marlow"
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. *;-) *My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). *I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

Allen

On 3/12/2010 10:11 AM, allen476 wrote:
On Mar 12, 9:07 am, wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. Baring
that, a wrench in the gears would do a lot. Remember, the tool
doesn't have to survive.

Well..... you're close Keith. How about "braking the blade", rather than
"breaking the blade"? Forcing an instant reversal of the motor direction to
stop the blade? Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. ;-) My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

The Sawstop on table saws forces a piece of metal into the blade in
addition to retracting it. The same would work on a band saw except
without the retraction. Not sure retracting the band saw blade would be
a good thing anyway unless it can reliably be broken in a specific spot
then moved reliably in a way that doesn't cause more harm than it prevents.

It's important to remember that just pulling the blade straight down
into the table will likely cause as much harm as continuing to run the
saw, while folding it back away from the teeth risks pinching fingers
that are behind the blade--one can touch a band saw blade from all sides.

Breaking the blade during stopping is a non-issue--if the device breaks
it so be it. They never let that be a consideration on the table saw
device so why would it be a consideration with a band saw? You're
weighing a hundred buck blade against a thousand times that much in
medical costs.

On Mar 12, 9:47*am, "J. Clarke" wrote:
On 3/12/2010 10:11 AM, allen476 wrote:



On Mar 12, 9:07 am, *wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. *;-) *My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). *I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

The Sawstop on table saws forces a piece of metal into the blade in
addition to retracting it. *The same would work on a band saw except
without the retraction. *Not sure retracting the band saw blade would be
a good thing anyway unless it can reliably be broken in a specific spot
then moved reliably in a way that doesn't cause more harm than it prevents.

Breaking the blade not only removes power but also the momentum of the
wheels and motor from driving the blade further. It seems reasonable
to break the blade to me, although as you say, it has to be done in
the right spot. A broken end shooting out of the saw doesn't seem
like a good idea.

It's important to remember that just pulling the blade straight down
into the table will likely cause as much harm as continuing to run the
saw, while folding it back away from the teeth risks pinching fingers
that are behind the blade--one can touch a band saw blade from all sides.

Breaking the blade during stopping is a non-issue--if the device breaks
it so be it. *They never let that be a consideration on the table saw
device so why would it be a consideration with a band saw? *You're
weighing a hundred buck blade against a thousand times that much in
medical costs.

The argument is exactly the same as the SS. Are false positives worth
the price for that one time where it saves your hand.

On Thu, 11 Mar 2010 18:51:08 -0800, "LDosser" wrote:

wrote in message
.. .
On Thu, 11 Mar 2010 17:00:00 -0600, (Robert
Bonomi) wrote:

In article ,
Mike Marlow wrote:
wrote:

Again - you can only patent a method.

Bull****.

So - are you suggesting you can patent the laws of physics?

Patents rarely specify the precise methodology employed to accomplish an
end.

They claim rights to "a method for .." accomplishing something.

If there _is_ existing competing technology, they have to spell out what
is 'different' about their approach -- that was *NOT* included in the
'a method for ..' claims of the prior patent(s).

If there is *NO* existing competing technology, and you have competently
drawn patent claims, the claim is for 'a method ...' doing the heretofore
impossible. citing the inventor's implementation only as one example of
the claim. In _that_ situation, *any*other* approach to solving the same
problem is simply a different means of doing the _same_thing_, and, as
such,
runs afoul of the original holder's patent that covers the basic idea of
doing _that_ thing.

A major goal of drafting patents is to make the claims as _broad_ and
_all-
encompassing_ as possible.

SawStop's patent(s), by 'virtue' of being the _first_of_its_kind_ are
very broad in scope. It will be 'difficult' (to put it mildly) to build
a competing technology that does _not_ involve: (1) 'a method for...'
detecting the approach of human anatomy to the blade, and/or (b) 'a method
for ...' removing the blade from potential contact.

Exactly right.

Read up on patents. There is nothing
at all stopping another company from coming up with a similar, or a
different approach.

The patent is on the detection of the digit. There are only so many
ways to detect the presence of the digit before it comes in contact
with the works. That's the physics. There isn't another good way and
if the patent attorney had any sense (it was his idea) he'd close off
all other avenues, as well.

He can patent the detection method only to the point of the device
design.
He can't patent the use of capacitance though.

WRONG.

If capacitance has never been used for that purpose previously, he _CAN_
patent 'the use of capacitance for that purpose'.

In fact, he's patented the use if *any* sensor for this purpose.


Prior Art: There exists all manner of machinery with sensors to keep human
appendages out of harms way.

....and payday is on Friday. So what?

On Mar 12, 11:34*am, " wrote:
On Mar 12, 9:47*am, "J. Clarke" wrote:



On 3/12/2010 10:11 AM, allen476 wrote:

On Mar 12, 9:07 am, *wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

wrote in message
...
On Thu, 11 Mar 2010 18:51:08 -0800, "LDosser" wrote:

wrote in message
. ..
On Thu, 11 Mar 2010 17:00:00 -0600, (Robert
Bonomi) wrote:

In article ,
Mike Marlow wrote:
wrote:

Again - you can only patent a method.

Bull****.

So - are you suggesting you can patent the laws of physics?

Patents rarely specify the precise methodology employed to accomplish an
end.

They claim rights to "a method for .." accomplishing something.

If there _is_ existing competing technology, they have to spell out what
is 'different' about their approach -- that was *NOT* included in the
'a method for ..' claims of the prior patent(s).

If there is *NO* existing competing technology, and you have competently
drawn patent claims, the claim is for 'a method ...' doing the
heretofore
impossible. citing the inventor's implementation only as one example of
the claim. In _that_ situation, *any*other* approach to solving the
same
problem is simply a different means of doing the _same_thing_, and, as
such,
runs afoul of the original holder's patent that covers the basic idea of
doing _that_ thing.

A major goal of drafting patents is to make the claims as _broad_ and
_all-
encompassing_ as possible.

SawStop's patent(s), by 'virtue' of being the _first_of_its_kind_ are
very broad in scope. It will be 'difficult' (to put it mildly) to build
a competing technology that does _not_ involve: (1) 'a method for...'
detecting the approach of human anatomy to the blade, and/or (b) 'a
method
for ...' removing the blade from potential contact.

Exactly right.

Read up on patents. There is nothing
at all stopping another company from coming up with a similar, or a
different approach.

The patent is on the detection of the digit. There are only so many
ways to detect the presence of the digit before it comes in contact
with the works. That's the physics. There isn't another good way
and
if the patent attorney had any sense (it was his idea) he'd close off
all other avenues, as well.

He can patent the detection method only to the point of the device
design.
He can't patent the use of capacitance though.

WRONG.

If capacitance has never been used for that purpose previously, he _CAN_
patent 'the use of capacitance for that purpose'.

In fact, he's patented the use if *any* sensor for this purpose.


Prior Art: There exists all manner of machinery with sensors to keep human
appendages out of harms way.

...and payday is on Friday. So what?


Prior art makes it easier to break.

allen476 wrote in
:

On Mar 12, 11:34*am, " wrote:
On Mar 12, 9:47*am, "J. Clarke" wrote:

*trim*

Breaking the blade during stopping is a non-issue--if the device
breaks it so be it. *They never let that be a consideration on the
table saw device so why would it be a consideration with a band
saw? *You're weighing a hundred buck blade against a thousand times
that much in medical costs.

The argument is exactly the same as the SS. *Are false positives
worth the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen


For a band saw, this might work.

For a table saw, what happens if you're using a molding head or dado
stack? There's a lot of mass there spinning quite quickly, so those
steel jaws would have to be quite massive themselves. (It would be good
for saw stability.)

Puckdropper
--
Never teach your apprentice everything you know.

On Mar 12, 9:25*pm, allen476 wrote:
On Mar 12, 11:34*am, " wrote:





On Mar 12, 9:47*am, "J. Clarke" wrote:

On 3/12/2010 10:11 AM, allen476 wrote:

On Mar 12, 9:07 am, *wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. *;-) *My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). *I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

The Sawstop on table saws forces a piece of metal into the blade in
addition to retracting it. *The same would work on a band saw except
without the retraction. *Not sure retracting the band saw blade would be
a good thing anyway unless it can reliably be broken in a specific spot
then moved reliably in a way that doesn't cause more harm than it prevents.

Breaking the blade not only removes power but also the momentum of the
wheels and motor from driving the blade further. *It seems reasonable
to break the blade to me, although as you say, it has to be done in
the right spot. *A broken end shooting out of the saw doesn't seem
like a good idea.

It's important to remember that just pulling the blade straight down
into the table will likely cause as much harm as continuing to run the
saw, while folding it back away from the teeth risks pinching fingers
that are behind the blade--one can touch a band saw blade from all sides.

Breaking the blade during stopping is a non-issue--if the device breaks
it so be it. *They never let that be a consideration on the table saw
device so why would it be a consideration with a band saw? *You're
weighing a hundred buck blade against a thousand times that much in
medical costs.

The argument is exactly the same as the SS. *Are false positives worth
the price for that one time where it saves your hand.

After thinking about it, one could design a braking system *in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen

I got my head around that and like that idea. But... there's a reason
the SawStop works as well and as quick as it does and that is that it
uses its own kinetic energy. A bandsaw's system would have to be pre-
loaded with instant release energy..such as hefty springs or shotgun-
type shells electrically fired. You wouldn't need much of a charge to
make stuff happen in a hurry. If you used energy stored in springs,
the release mechanisms themselves would add unwanted time to the event.

In article ,
LDosser wrote:
wrote in message
.. .
On Thu, 11 Mar 2010 18:51:08 -0800, "LDosser" wrote:

wrote in message
...
On Thu, 11 Mar 2010 17:00:00 -0600, (Robert
Bonomi) wrote:

In article ,
Mike Marlow wrote:
wrote:

Again - you can only patent a method.

Bull****.

So - are you suggesting you can patent the laws of physics?

Patents rarely specify the precise methodology employed to accomplish an
end.

They claim rights to "a method for .." accomplishing something.

If there _is_ existing competing technology, they have to spell out what
is 'different' about their approach -- that was *NOT* included in the
'a method for ..' claims of the prior patent(s).

If there is *NO* existing competing technology, and you have competently
drawn patent claims, the claim is for 'a method ...' doing the
heretofore
impossible. citing the inventor's implementation only as one example of
the claim. In _that_ situation, *any*other* approach to solving the
same
problem is simply a different means of doing the _same_thing_, and, as
such,
runs afoul of the original holder's patent that covers the basic idea of
doing _that_ thing.

A major goal of drafting patents is to make the claims as _broad_ and
_all-
encompassing_ as possible.

SawStop's patent(s), by 'virtue' of being the _first_of_its_kind_ are
very broad in scope. It will be 'difficult' (to put it mildly) to build
a competing technology that does _not_ involve: (1) 'a method for...'
detecting the approach of human anatomy to the blade, and/or (b) 'a
method
for ...' removing the blade from potential contact.

Exactly right.

Read up on patents. There is nothing
at all stopping another company from coming up with a similar, or a
different approach.

The patent is on the detection of the digit. There are only so many
ways to detect the presence of the digit before it comes in contact
with the works. That's the physics. There isn't another good way
and
if the patent attorney had any sense (it was his idea) he'd close off
all other avenues, as well.

He can patent the detection method only to the point of the device
design.
He can't patent the use of capacitance though.

WRONG.

If capacitance has never been used for that purpose previously, he _CAN_
patent 'the use of capacitance for that purpose'.

In fact, he's patented the use if *any* sensor for this purpose.


Prior Art: There exists all manner of machinery with sensors to keep human
appendages out of harms way.

...and payday is on Friday. So what?


Prior art makes it easier to break.


If nobody has ever used a sensor to keep human appendages out of harms way
_on_a_table_saw_, then one _can_ patent the concept of 'using a sensor on a
table saw' for that purpose, *REGARDLESS* of the 'prior art' that exists
with regard to other kinds of devices. That patent would cover *any* kind
of sensor used _for_that_purpose_ *ON*A*TABLE*SAW*. To come up with a
'competing technology' for a table saw, *without* infringing that patent,
one would have to do it _without_ using a sensor.

In that scenario, the difficulties in producing such a competing technology
should be obvious.

On Fri, 12 Mar 2010 18:25:25 -0800 (PST), allen476 wrote:

On Mar 12, 11:34*am, " wrote:
On Mar 12, 9:47*am, "J. Clarke" wrote:



On 3/12/2010 10:11 AM, allen476 wrote:

On Mar 12, 9:07 am, *wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. *;-) *My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). *I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

The Sawstop on table saws forces a piece of metal into the blade in
addition to retracting it. *The same would work on a band saw except
without the retraction. *Not sure retracting the band saw blade would be
a good thing anyway unless it can reliably be broken in a specific spot
then moved reliably in a way that doesn't cause more harm than it prevents.

Breaking the blade not only removes power but also the momentum of the
wheels and motor from driving the blade further. *It seems reasonable
to break the blade to me, although as you say, it has to be done in
the right spot. *A broken end shooting out of the saw doesn't seem
like a good idea.

It's important to remember that just pulling the blade straight down
into the table will likely cause as much harm as continuing to run the
saw, while folding it back away from the teeth risks pinching fingers
that are behind the blade--one can touch a band saw blade from all sides.

Breaking the blade during stopping is a non-issue--if the device breaks
it so be it. *They never let that be a consideration on the table saw
device so why would it be a consideration with a band saw? *You're
weighing a hundred buck blade against a thousand times that much in
medical costs.

The argument is exactly the same as the SS. *Are false positives worth
the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Instead of a mechanical disconnect from the motor to the wheels, use the motor
itself as part of the solution (regen braking, sorta). Faster than a gear
change I would think, anyway.

On Fri, 12 Mar 2010 18:58:18 -0800, "LDosser" wrote:

wrote in message
.. .
On Thu, 11 Mar 2010 18:51:08 -0800, "LDosser" wrote:

wrote in message
...
On Thu, 11 Mar 2010 17:00:00 -0600, (Robert
Bonomi) wrote:

In article ,
Mike Marlow wrote:
wrote:

Again - you can only patent a method.

Bull****.

So - are you suggesting you can patent the laws of physics?

Patents rarely specify the precise methodology employed to accomplish an
end.

They claim rights to "a method for .." accomplishing something.

If there _is_ existing competing technology, they have to spell out what
is 'different' about their approach -- that was *NOT* included in the
'a method for ..' claims of the prior patent(s).

If there is *NO* existing competing technology, and you have competently
drawn patent claims, the claim is for 'a method ...' doing the
heretofore
impossible. citing the inventor's implementation only as one example of
the claim. In _that_ situation, *any*other* approach to solving the
same
problem is simply a different means of doing the _same_thing_, and, as
such,
runs afoul of the original holder's patent that covers the basic idea of
doing _that_ thing.

A major goal of drafting patents is to make the claims as _broad_ and
_all-
encompassing_ as possible.

SawStop's patent(s), by 'virtue' of being the _first_of_its_kind_ are
very broad in scope. It will be 'difficult' (to put it mildly) to build
a competing technology that does _not_ involve: (1) 'a method for...'
detecting the approach of human anatomy to the blade, and/or (b) 'a
method
for ...' removing the blade from potential contact.

Exactly right.

Read up on patents. There is nothing
at all stopping another company from coming up with a similar, or a
different approach.

The patent is on the detection of the digit. There are only so many
ways to detect the presence of the digit before it comes in contact
with the works. That's the physics. There isn't another good way
and
if the patent attorney had any sense (it was his idea) he'd close off
all other avenues, as well.

He can patent the detection method only to the point of the device
design.
He can't patent the use of capacitance though.

WRONG.

If capacitance has never been used for that purpose previously, he _CAN_
patent 'the use of capacitance for that purpose'.

In fact, he's patented the use if *any* sensor for this purpose.


Prior Art: There exists all manner of machinery with sensors to keep human
appendages out of harms way.

...and payday is on Friday. So what?


Prior art makes it easier to break.

That is *not* prior art.

In article ,
Puckdropper puckdropper(at)yahoo(dot)com wrote:
allen476 wrote in
:

On Mar 12, 11:34*am, " wrote:
On Mar 12, 9:47*am, "J. Clarke" wrote:

*trim*

Breaking the blade during stopping is a non-issue--if the device
breaks it so be it. *They never let that be a consideration on the
table saw device so why would it be a consideration with a band
saw? *You're weighing a hundred buck blade against a thousand times
that much in medical costs.

The argument is exactly the same as the SS. *Are false positives
worth the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen


For a band saw, this might work.

For a table saw, what happens if you're using a molding head or dado
stack? There's a lot of mass there spinning quite quickly, so those
steel jaws would have to be quite massive themselves. (It would be good
for saw stability.)

Seems like it'd have _real_ problems with a 'wobble dado', too.

"Puckdropper" puckdropper(at)yahoo(dot)com wrote in message
...
allen476 wrote in
:

On Mar 12, 11:34 am, " wrote:
On Mar 12, 9:47 am, "J. Clarke" wrote:

*trim*

Breaking the blade during stopping is a non-issue--if the device
breaks it so be it. They never let that be a consideration on the
table saw device so why would it be a consideration with a band
saw? You're weighing a hundred buck blade against a thousand times
that much in medical costs.

The argument is exactly the same as the SS. Are false positives
worth the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen


For a band saw, this might work.

For a table saw, what happens if you're using a molding head or dado
stack? There's a lot of mass there spinning quite quickly, so those
steel jaws would have to be quite massive themselves. (It would be good
for saw stability.)

Not really. Think of a cars brake caliper. If it can lock up your wheel (if
it were not for the ABS POS), it can do a blade.

On 3/13/2010 10:20 PM, CW wrote:
"Puckdropper"puckdropper(at)yahoo(dot)com wrote in message
...
wrote in
:

On Mar 12, 11:34 am, wrote:
On Mar 12, 9:47 am, "J. wrote:

*trim*

Breaking the blade during stopping is a non-issue--if the device
breaks it so be it. They never let that be a consideration on the
table saw device so why would it be a consideration with a band
saw? You're weighing a hundred buck blade against a thousand times
that much in medical costs.

The argument is exactly the same as the SS. Are false positives
worth the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen


For a band saw, this might work.

For a table saw, what happens if you're using a molding head or dado
stack? There's a lot of mass there spinning quite quickly, so those
steel jaws would have to be quite massive themselves. (It would be good
for saw stability.)

Not really. Think of a cars brake caliper. If it can lock up your wheel (if
it were not for the ABS POS), it can do a blade.

(a) the problem is not locking the blade, the problem is locking it so
fast that it doesn't cut you.

(b) why do you consider ABS to be "POS"? There is no circumstance on a
paved road under which locked brakes confer any kind of benefit except
when there is fairly deep snow.

On Mar 13, 1:56*pm, Robatoy wrote:
On Mar 12, 9:25*pm, allen476 wrote:



On Mar 12, 11:34*am, " wrote:

On Mar 12, 9:47*am, "J. Clarke" wrote:

On 3/12/2010 10:11 AM, allen476 wrote:

On Mar 12, 9:07 am, *wrote:
On Mar 12, 6:11 am, "Mike
wrote:

wrote:

Breaking the blade, if done in the right place, might work. *Baring
that, a wrench in the gears would do a lot. *Remember, the tool
doesn't have to survive.

Well..... you're close Keith. *How about "braking the blade", rather than
"breaking the blade"? *Forcing an instant reversal of the motor direction to
stop the blade? *Or clamping a brake on the pulley or on the arbor.

Sure, there are ways of stopping the blade quickly but Allen thought
that braking the blade would break it. *;-) *My point was that this
might not be a bad thing, if done in the right spot (or at least not
the wrong one). *I also wouldn't think a band saw would have to be
stopped as quickly as a table saw to minimize damage.

Poor choice of words at 10:30 last night, teach me to type half
asleep.

A bandsaw however would have to stop at the same amount of time. If it
was a 3 tpi blade, it would do some damage rather quickly. The only
solution would be either a guard that came up from the table or a
mechanism that would cut the blade then retract both ends away from
the work area.

A braking system, hmmmm, might be an alternative. Then it wouldn't be
destroying a nice blade. But how?

The Sawstop on table saws forces a piece of metal into the blade in
addition to retracting it. *The same would work on a band saw except
without the retraction. *Not sure retracting the band saw blade would be
a good thing anyway unless it can reliably be broken in a specific spot
then moved reliably in a way that doesn't cause more harm than it prevents.

Breaking the blade not only removes power but also the momentum of the
wheels and motor from driving the blade further. *It seems reasonable
to break the blade to me, although as you say, it has to be done in
the right spot. *A broken end shooting out of the saw doesn't seem
like a good idea.

It's important to remember that just pulling the blade straight down
into the table will likely cause as much harm as continuing to run the
saw, while folding it back away from the teeth risks pinching fingers
that are behind the blade--one can touch a band saw blade from all sides.

Breaking the blade during stopping is a non-issue--if the device breaks
it so be it. *They never let that be a consideration on the table saw
device so why would it be a consideration with a band saw? *You're
weighing a hundred buck blade against a thousand times that much in
medical costs.

The argument is exactly the same as the SS. *Are false positives worth
the price for that one time where it saves your hand.

After thinking about it, one could design a braking system *in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen

I got my head around that and like that idea. But... there's a reason
the SawStop works as well and as quick as it does and that is that it
uses its own kinetic energy. A bandsaw's system would have to be pre-
loaded with instant release energy..such as hefty springs or shotgun-
type shells electrically fired. You wouldn't need much of a charge to
make stuff happen in a hurry. If you used energy stored in springs,
the release mechanisms themselves would add unwanted time to the event.


The design I suggested would be for a bandsaw. I would use
electromagnetic releases for the safety with a spring counter to that.
Almost the same idea for the blade clamping system, except using what
looks like jaws from a pair of vice grips. My goal would be not to
destroy some expensive part along with an expensive blade.

Tablesaw design however would be more difficult. I did think about a
caliper type system. Dadoes would be the negating factor to that
though.

Allen

"J. Clarke" wrote in message
...
On 3/13/2010 10:20 PM, CW wrote:
"Puckdropper"puckdropper(at)yahoo(dot)com wrote in message
...
wrote in
:

On Mar 12, 11:34 am, wrote:
On Mar 12, 9:47 am, "J. wrote:

*trim*

Breaking the blade during stopping is a non-issue--if the device
breaks it so be it. They never let that be a consideration on the
table saw device so why would it be a consideration with a band
saw? You're weighing a hundred buck blade against a thousand times
that much in medical costs.

The argument is exactly the same as the SS. Are false positives
worth the price for that one time where it saves your hand.

After thinking about it, one could design a braking system in a 2
part design. A set of steel jaws that clamp the blade and a mechanism
to disengage the motor from the wheels. Instead of direct drive, one
could use 2 gears to drive the wheels, when the safety engages, a
spring would retract the motor and the jaws would engage stopping the
blade. Shouldn't damage the machine and a good chance that it won't
damage the blade as well.

Allen


For a band saw, this might work.

For a table saw, what happens if you're using a molding head or dado
stack? There's a lot of mass there spinning quite quickly, so those
steel jaws would have to be quite massive themselves. (It would be good
for saw stability.)

Not really. Think of a cars brake caliper. If it can lock up your wheel
(if
it were not for the ABS POS), it can do a blade.

(a) the problem is not locking the blade, the problem is locking it so
fast that it doesn't cut you.

(b) why do you consider ABS to be "POS"? There is no circumstance on a
paved road under which locked brakes confer any kind of benefit except
when there is fairly deep snow.

RE (b) I used to like taking my big rear wheel drive car with it's 455 CID
V8 out on snowy days on parking lots and skidding/sliding it around when I
was a kid.... Isn't entertainment a benefit? ;~)

John

PS, On the other hand ABS probably saved my life two years ago when a
tractor trailer in the right lane of a two lane on-ramp changed lanes while
I was next to him. There was no room to out-race him out the front... The
ABS allowed me to stop quickly and steer up close to the guard rail under
control. Net result was my 6 week old car was still totaled but I walked out
of the hospital... beat up but no internal injuries or broken bones. The
left side was wrecked bumper to bumper from being crushed into the guard
rail and the right side bumper to bumper from the truck trailer driving
through the right rear quarter and down the side. Two wheels were broken
off. If I hadn't gotten up close to the guard rail before he hit me I would
have been completely under the trailer wheels...