Patents by Inventor Siavash Eshghy
Siavash Eshghy has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6513812Abstract: A novel sealing device is disclosed that provides an enhanced seal at the interface between a rotary shaft and a stationary housing for automotive applications such as transmissions and axle assemblies. The sealing device preferably includes a first seal that has a plurality of turbine blade portions. As the first seal rotates with the shaft, the turbine blade portions create a hydrodynamic flow or fluid disturbance in the vicinity of the interface that effectively blows away contaminants as they approach the interface between the rotary shaft and the housing. A second seal takes one of two forms. One is a radial lip seal that includes a pocket portion between two contact surfaces. A plurality of openings allow lubricant from the system to enter into the pocket portion, which provides lubricant along the contact surfaces of the lip seal. The presence of the lubricant enhances the seal life.Type: GrantFiled: May 5, 1997Date of Patent: February 4, 2003Assignee: ArvinMeritor Technology, LLCInventors: Jibin Yang, Siavash Eshghy
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Patent number: 5433301Abstract: A force application system for a disc brake assembly in which twin pistons engage a configured load plate featuring stiffening ribs at specific locations to maximize the stiffness thereof seeking to provide uniformity of pressure transmitted therethrough to a friction pad. Additional uniformity of pressure is achieved by forming recesses in the backing plate of the friction pad proximate regions of pressure peaks. A singular recess at the point of pressure peak or recesses defined in a pattern identified by infinite element analysis may be utilized to optimize uniformity of pressure distribution.Type: GrantFiled: December 13, 1993Date of Patent: July 18, 1995Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 5284217Abstract: An apparatus for tightening threaded fasteners to any desired proportion of the way through a torque-angle specification window defined by low and high angle limits and low and high torque limits. The torque rate for the joint is determined from torque and angle measurements taken during tightening and compared to boundary ratios which are determined as the rates of change of torque with respect to angle from a threshold torque to the corners of the specification window. A final target parameter value of either torque or angle is calculated based upon this comparison which is approximately halfway through the specification window along a projection of a torque-angle characteristic curve for the fastener which is determined from the torque rate. Correction factors are also provided for tool overrun depending upon whether torque or angle control is used and a reject rate margin is employed to account for nonlinearities which otherwise may lead to unacceptable assemblies.Type: GrantFiled: April 7, 1993Date of Patent: February 8, 1994Assignee: Allen-Bradley Company, Inc.Inventor: Siavash Eshghy
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Patent number: 5212862Abstract: A method for tightening threaded fasteners to any desired proportion of the way through a torque-angle specification window defined by low and high angle limits and low and high torque limits. The torque rate for the joint is determined from torque and angle measurements taken during tightening and compared to boundary ratios which are determined as the rates of change of torque with respect to angle from a threshold torque to the corners of the specification window. A final target parameter value of either torque or angle is calculated based upon this comparison which is approximately halfway through the specification window along a projection of a torque-angle characteristic curve for the fastener which is determined from the torque rate. Correction factors are also provided for tool overrun depending upon whether torque or angle control is used and a reject rate margin is employed to account for nonlinearities which otherwise may lead to unacceptable assemblies.Type: GrantFiled: June 2, 1992Date of Patent: May 25, 1993Assignee: Allen-Bradley Company, Inc.Inventor: Siavash Eshghy
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Patent number: 5131130Abstract: A method and apparatus for tightening threaded fasteners to any desired proportion of the way through a torque-angle specification window defined by low and high angle limits and low and high torque limits. The torque rate for the joint is determined from torque and angle measurements taken during tightening and compared to boundary ratios which are determined as the rates of change of torque with respect to angle from a threshold torque to the corners of the specification window. A final target parameter value of either torque or angle is calculated based upon this comparison which is approximately halfway through the specification window along a projection of a torque-angle characteristic curve for the fastener which is determined from the torque rate. Correction factors are also provided for tool overrun depending upon whether torque or angle control is used and a reject rate margin is employed to account for nonlinearities which otherwise may lead to unacceptable assemblies.Type: GrantFiled: October 9, 1990Date of Patent: July 21, 1992Assignee: Allen-Bradley Company, Inc.Inventor: Siavash Eshghy
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Patent number: 4995145Abstract: A method of reducing variations in the static torque of threaded fasteners, as measured after a relaxation period, uses an instrumented nutrunner to "break" the joint. Breaking the joint is done by monitoring the torque and angle of the fastener during a torque recovery cycle. The angle of the fastener is advanced until a threshold torque is reached and then the fastener is turned an additional predetermined number of degrees. A static audit may be simultaneously performed by storing torque and angle values. Static torque is distinguished from break away torque by detecting the point of minimum curvature of the subsequently produced torque angle curve.Type: GrantFiled: January 8, 1990Date of Patent: February 26, 1991Assignee: Allen-Bradley Company, Inc.Inventor: Siavash Eshghy
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Patent number: 4361945Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: December 7, 1982Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4305471Abstract: A fastening tool, which is preferably portable, incorporates torque and angle sensors connected to an analog calculating circuit which determines, while tightening below the yield point of any component of the joint being tightened, a final shut off parameter which varies from joint to joint while tightening seriatim a plurality of substantially identical joints. The logarithimic rate method is used to determine the final shut off parameter. In accordance with one embodiment of the invention, a simplification occurs by the measurement of an angle interval occurring between two predetermined torque values. In accordance with another embodiment of the invention, a simplification occurs by measuring the torque value existing at a predetermined angle interval beyond a first predetermined torque level.Type: GrantFiled: January 10, 1980Date of Patent: December 15, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4285112Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: August 25, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4282640Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: August 11, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4280380Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: July 28, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4274188Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: August 17, 1979Date of Patent: June 23, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4268944Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: May 26, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4267629Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: May 19, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4259773Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empiricallly determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: April 7, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4259772Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: April 7, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4259775Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance of how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: April 7, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4255846Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fasteners is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: March 17, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: 4246685Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: April 19, 1979Date of Patent: January 27, 1981Assignee: Rockwell International CorporationInventor: Siavash Eshghy
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Patent number: RE31569Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.Type: GrantFiled: December 21, 1981Date of Patent: May 1, 1984Assignee: Rockwell International CorporationInventor: Siavash Eshghy