Poulan 2050 User Manual - Page 5

Chain Brake And Cka Angle - service manual

Page 5 highlights

has been demonstrated to significantly reduce the number and seriousness of kickbacks when tested in accordance with safety requirements for gasoline powered chain saws as set by ANSI B175.1. Reduced Kickback Symmetrical Guide Bar Small Radius Tip Symmetrical Guide Bar toward the operator. Either of these events may cause you to lose control of the saw which could result in serious injury or even death. DO NOT RELY UPON ANY OF THE DEVICES BUILT INTO YOUR SAW. YOU SHOULD USE THE SAW PROPERLY AND CAREFULLY TO AVOID KICKBACK. Reduced--kickback guide bars and low--kickback saw chains reduce the chance and magnitude of kickback and are recommended. Your saw has a low kickback chain and bar as original equipment. Repairs on a chain brake should be made by an authorized servicing dealer. Take your unit to the place of purchase if purchased from a servicing dealer, or to the nearest authorized master service dealer. Large Radius Tip S Low--Kickback Chain, designed with a contoured depth gauge and guard link which deflect kickback force and allow wood to gradually ride into the cutter. Low-Kickback Chain has met kickback performance requirements when tested on a representative sample of chain saws below 3.8 cubic inch displacement specified in ANSI B175.1. Contoured Depth Gauge Elongated Guard Link Low --- Kickback Chain Deflects Kickback Force And Allows Wood To Gradually Ride Into Cutter WARNING: Computed kickback angle (CKA) listed on your saw and listed in the CKA table below represents angle of kickback your bar and chain combinations will have when tested in accordance with CSA (Canadian Standards Association) and ANSI standards. When purchasing replacement bar and chain, considerations should be given to the lower CKA values. Lower CKA values represent safer angles to the user, higher values indicate more angle and higher kick energies. Computed angles represented in the non-activated column indicate total energy and angle associated without activation of the chain brake during kickback. In all cases lower CKA values represent a safer operating environment for the user. Can Obstruct Material Chain With High Kickback Potential S Front Hand Guard, designed to reduce the chance of your left hand contacting the chain if your hand slips off the front handlebar. S Position of front and rear handlebars, designed with distance between handles and "in-line" with each other. The spread and "in-line" position of the hands provided by this design work together to give balance and resistance in controlling the pivot of the saw back toward the operator if kickback occurs. CHAIN BRAKE AND CKA ANGLE S Chain Brake, designed to stop the chain in the event of kickback. WARNING: WE DO NOT REP- RESENT AND YOU SHOULD NOT ASSUME THAT THE CHAIN BRAKE WILL PROTECT YOU IN THE EVENT OF A KICKBACK. Kickback is a lightning fast action which throws the bar and rotating chain back and up toward the operator. Kickback can be caused by allowing contact of the bar tip in the danger zone with any hard object. Kickback can also be caused by pinching the saw chain along the top of the guide bar. This action may push the guide bar rapidly back S Tip contact in some cases may cause a lightning fast reverse REACTION, kicking the guide bar up and back toward the operator. S Pinching the saw chain along the top of the guide bar may push the guide bar rapidly back toward the operator. S Either of these reactions may cause you to lose control of the saw which could result in serious injury.Do not rely exclusively upon the safety devices built into your saw. The following guide bar and chain combinations meet kickback requirements of CSA Standards Z62.1, Z62.3, & ANSI B175.1 when used on saws listed in this manual. Use of bar and chain combinations other than those listed is not recommended and may not meet the CKA requirements per standard. STANDARDS: This saw is listed by Underwriter's Laboratories, Inc., in accordance with: ANSI B175.1-1991 "American National Standard for Powered Tools -- Gasoline Powered Chain Saw -- Safety Requirements." CSA Z62.1 "Chain Saws -- Occupational Health and Safety" CSA Z62.3 "Chain Saw Kickback Occupational Health and Safety" 5

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5
has been demonstrated to significantly re-
duce the number and seriousness of kick-
backs when tested in accordance with
safety requirements for gasoline powered
chain saws as set by ANSI B175.1.
Small Radius Tip
Symmetrical Guide Bar
Reduced Kickback Symmetrical Guide Bar
Large Radius Tip
S
Low--Kickback
Chain, designed
with a
contoured depth gauge and guard link
which deflect kickback force and allow
wood to gradually ride into the cutter. Low--
Kickback Chain has met kickback per-
formance requirements when tested on a
representative sample of chain saws be-
low 3.8 cubic inch displacement specified
in ANSI B175.1.
Low---Kickback
Chain
Chain With High Kickback Potential
Can Obstruct Material
Contoured Depth Gauge
Elongated Guard Link
Deflects
Kickback Force
And Allows Wood
To Gradually
Ride Into Cutter
S
Front Hand Guard, designed to reduce the
chance of your left hand contacting the
chain if your hand slips off the front handle-
bar.
S
Position of front and rear handlebars, de-
signed with distance between handles and
“in-line” with each other. The spread and
“in-line” position of the hands provided by
this design work together to give balance
and resistance in controlling the pivot of
the saw back toward the operator if kick-
back occurs.
CHAIN BRAKE AND CKA ANGLE
S
Chain Brake, designed to stop the chain in
the event of kickback.
WARNING:
WE DO NOT REP-
RESENT AND YOU SHOULD NOT AS-
SUME THAT THE CHAIN BRAKE WILL
PROTECT YOU IN THE EVENT OF A
KICKBACK. Kickback is a lightning fast ac-
tion which throws the bar and rotating chain
back and up toward the operator. Kickback
can be caused by allowing contact of the bar
tip in the danger zone with any hard object.
Kickback can also be caused by pinching the
saw chain along the top of the guide bar. This
action may push the guide bar rapidly back
toward the operator. Either of these events
may cause you to lose control of the saw
which could result in serious injury or even
death. DO NOT RELY UPON ANY OF THE
DEVICES BUILT INTO YOUR SAW. YOU
SHOULD USE THE SAW PROPERLY AND
CAREFULLY TO AVOID KICKBACK.
Re-
duced--kickback guide bars and low--kick-
back saw chains reduce the chance and
magnitude
of
kickback
and
are recom-
mended. Your saw has a low kickback chain
and bar as original equipment. Repairs on a
chain brake should be made by an autho-
rized servicing dealer. Take your unit to the
place of purchase if purchased from a ser-
vicing dealer, or to the nearest authorized
master service dealer.
WARNING:
Computed kickback
angle (CKA) listed on your saw and listed in
the
CKA table below represents angle of
kickback your bar and chain combinations
will have when tested in accordance with
CSA (Canadian Standards Association) and
ANSI standards. When purchasing replace-
ment bar and chain, considerations should
be given to the lower CKA values. Lower
CKA values represent safer angles to the
user, higher values indicate more angle and
higher kick energies. Computed angles rep-
resented in the non-activated column indi-
cate total energy and angle associated with-
out activation of the chain brake during
kickback. In all cases lower CKA values rep-
resent a safer operating environment for the
user.
S
Tip contact in some cases may
cause
a
lightning
fast
reverse
REACTION, kicking the guide bar
up and back toward the operator.
S
Pinching the saw chain along the
top of the guide bar may push the
guide bar rapidly back toward the
operator.
S
Either of these reactions may cause
you to lose control of the saw which
could result in serious injury.Do not
rely exclusively upon the safety de-
vices built into your saw.
The following guide bar and chain combina-
tions meet kickback requirements of CSA
Standards Z62.1, Z62.3, & ANSI B175.1
when used on saws listed in this manual.
Use of bar and chain combinations other
than those listed is not recommended and
may not meet the CKA requirements per
standard.
STANDARDS:
This saw is listed by Un-
derwriter’s Laboratories, Inc., in accordance
with:
ANSI
B175.1-1991
“American
National
Standard
for Powered Tools
-- Gasoline
Powered
Chain Saw
--
Safety
Require-
ments.”
CSA Z62.1
“Chain Saws -- Occupational
Health and Safety”
CSA Z62.3
“Chain Saw Kickback Occupa-
tional Health and Safety”