Tension control of fasteners

Claim 2

Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value, below the yield point of .[.any component.]. .Iadd.all joint components .Iaddend.that can be correlated with stress, appearing in the fastener, comprising a powered instructable tool, capable of terminating tightening in response to an instruction which varies from one fastener to the next, for applying torque to the fastener and tightening the same; means for sensing the torque applied to the fastener at various angles of advance; means responsive to the torque and angle sensings for determining, while tightening below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress, a tightening parameter value, variable from one fastener to the next, sufficient to tighten each fastener to the final desired stress value; and means for instructing the tool to terminate tightening of each fastener in response to the determined tightening parameter value.

Claim 3

The apparatus of claim 1 wherein the determining means comprises means for determining the torque values sufficient to tighten each fastener to the final desired stress value.

Claim 4

The apparatus of claim 2 wherein the determining means comprises means for calculating the sufficient torque value from the ultimate equation ##EQU34## where F D is the final desired stress value, dF/dα is the derivative of stress with respect to angle, T D is the sufficient torque value, dT/dα is the derivative of torque with respect to angle, T os is offset torque, and T pv is prevailing torque.

Claim 5

The apparatus of claim 1 wherein the determining means comprises means for determining the angle of threading advance sufficient to tighten each fastener to the final desired stress value.

Claim 6

The apparatus of claim 4 wherein the determining means comprises means for calculating the angle of advance from the ultimate equation F D =αFR where F D is the final desired stress value, FR is the stress rate and α is the angular distance from the angle origin of stress to F D . .[.6. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of any joint component that can be correlated with stress, including tightening the fastener with an instructable tool; sensing torque at various angles of advance during tightening below the yield point of any joint component that can be correlated with stress; calculating, while tightening below the yield point of any joint component that can be correlated with stress, the stress appearing in the fastener at least at one instant of tightening below the yield point of any joint component that can be correlated with stress from the sensed values of torque and angle; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of any joint component that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener to the determined parameter; and terminating tightening in response to the attainment of the determined

Claim 7

parameter..]. 7. The method of claim .[.6.]. .Iadd.51 .Iaddend.wherein the

Claim 8

tightening parameter is angle of advance. 8. The method of claim .[.6.].

Claim 9

.Iadd.51 .Iaddend.wherein the tightening parameter is torque. 9. The method of claim .[.6.]. .Iadd.51 .Iaddend.wherein the tightening parameter

Claim 10

is a linear combination of torque and angle. 10. The method of claim .[.6.]. .Iadd.51 .Iaddend.wherein fastener is a bolt and the final desired

Claim 11

stress value is final desired tension value in the bolt. 11. The method of claim .[.6.]. .Iadd.51 .Iaddend.wherein the tightening parameter includes a measure of tool overrun. .[.12. Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value below the yield point, comprising a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening below the yield point of any joint component that can be correlated with stress; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of any joint component that can be correlated with stress from the sensed values of torque and angle; means for determining a tightening parameter value sufficient to tighten the fastener to the final desired stress value below the yield point of any joint component that can be correlated with stress from the calculated stress; and means for instructing the tool to tighten the fastener to the determined

Claim 12

parameter value..]. 13. The apparatus of claim .[.12.]. .Iadd.52 .Iaddend.wherein the calculating means and the determining means respectively comprises means for calculating the stress and means for determining the tightening parameter value in a time period commencing with the onset of threading and stopping with the termination of

Claim 13

tightening. 14. The apparatus of claim 13 wherein the time period is less than two minutes. .[.15. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of any joint component that can be correlated with stress, comprising tightening the fastener with an instructable powered tool; sensing torque at various angles of advance during tightening; determining the torque rate of the fastener from the sensed values of torque and angle; calculating the stress appearing in the fastener at least at least at one instant of tightening below the yield point of any joint component that can be correlated with stress from the determined torque rate and from sensed torque; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of any joint component that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener in response to the determined parameter; and

Claim 14

terminating tightening in response to the determined parameter..]. 16. The method of claim .[.15.]. .Iadd.53 .Iaddend.further comprising predicting the amount of tool overrun and wherein the instructing step comprises instructing the tool to tighten each fastener in response to the determined parameter and the amount of tool overrun, and the terminating step comprises terminating tightening in response to the determined

Claim 15

parameter and the amount of tool overrun. 17. The method of claim .[.15.]. .Iadd.53 .Iaddend.comprising the step of empirically determining the value of FR 1 , FR 2 and T os where FR 1 is stress rate in a low stress range, FR 2 is stress rate in a higher stress range and T os is offset torque, and the calculating step comprises calculating the stress from the empirically determined values of FR 1 , FR 2 and T os as well as from the sensed values of torque and angle. .[.18. Apparatus for tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of any joint component that can be correlated with stress, comprising a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening; means for determining the torque rate of the fastener from the sensed values of torque and angle; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of any joint component that can be correlated with stress from the determined torque rate and the sensed torque; means for determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of any joint component that can be correlated with stress; and means for instructing the tool to tighten the fastener in response to the

Claim 16

determined parameter..]. 19. The apparatus of claim .[.18.]. .Iadd.54 .Iaddend.further comprising means for predicting the amount of tool overrun, and wherein the instructing means comprises means for instructing the tool to tighten the fastener in response to the determined parameter

Claim 17

and the amount of tool overrun. 20. The apparatus of claim .[.18.]. .Iadd.54 .Iaddend.wherein the determining means comprises means for determining the torque value sufficient to tighten the fastener to the

Claim 18

final desired stress value. 21. The apparatus of claim .[.18.]. .Iadd.54 .Iaddend.wherein the determining means comprises means for determining the angle of threading advance sufficient to tighten the fastener to the final

Claim 19

desired stress value. 22. The apparatus of claim .[.18.]. .Iadd.54 .Iaddend.wherein the fastener is a bolt and the calculating means

Claim 20

comprises means for calculating the tension in the bolt. 23. Apparatus for tightening a joint having components including at least one threaded fastener, comprising a powered tool for tightening the fastener; means for monitoring stress in the fastener including means for sensing torque and angle while tightening; and data processor means for calculating stress in the fastener below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress from sensed values of torque and angle; and means for terminating tightening in response to a tightening parameter

Claim 21

comprises means for calculating the tension in the bolt. 23. Apparatus for tightening a joint having components including at least one threaded fastener, comprising a powered tool for tightening the fastener; means for monitoring stress in the fastener including means for sensing torque and angle while tightening; and data processor means for calculating stress in the fastener below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress from sensed values of torque and angle; and means for terminating tightening in response to a tightening parameter

Claim 22

related to monitored stress. 24. The apparatus of claim 23 wherein the

Claim 23

tightening parameter is torque. 25. The apparatus of claim 23 wherein the

Claim 24

tightening parameter is angle. 26. The apparatus of claim 23 wherein the

Claim 25

tightening parameter is a linear combination of torque and angle. 27. Apparatus for tightening substantially identical threaded fasteners in production lots to the same final desired stress value ±15%, comprising a powered instructable tightening tool having a source of energy, means for connecting and disconnecting the tool to the energy source, a torque sensor and an angle sensor; a data processor connected to the torque and angle sensors including means for determining a mid-point stop of the fasteners at least about 0.4 elastic limit of the weakest joint component from a sensed value of torque and angle and means for instructing the tool to halt tightening at the mid-point stop; means for calculating a torque rate in a region adjacent the mid-point stop from sensed values of torque and angle; means for calculating the stress appearing in the fastener at a location between the onset of tightening and the mid-point stop from a sensed value of torque at the location, the calculated torque rate and an empirically determined stress rate for the region including 0.1-0.5 elastic limit; means for calculating a value of a tightening parameter sufficient to tighten the fastener to a final desired stress value from an empirically determined stress rate above the region 0.1-0.5 elastic limit; means controlled by the data processor for resuming tightening; and means responsive to the value of the tightening parameter for terminating

Claim 26

tightening parameter is a linear combination of torque and angle. 27. Apparatus for tightening substantially identical threaded fasteners in production lots to the same final desired stress value ±15%, comprising a powered instructable tightening tool having a source of energy, means for connecting and disconnecting the tool to the energy source, a torque sensor and an angle sensor; a data processor connected to the torque and angle sensors including means for determining a mid-point stop of the fasteners at least about 0.4 elastic limit of the weakest joint component from a sensed value of torque and angle and means for instructing the tool to halt tightening at the mid-point stop; means for calculating a torque rate in a region adjacent the mid-point stop from sensed values of torque and angle; means for calculating the stress appearing in the fastener at a location between the onset of tightening and the mid-point stop from a sensed value of torque at the location, the calculated torque rate and an empirically determined stress rate for the region including 0.1-0.5 elastic limit; means for calculating a value of a tightening parameter sufficient to tighten the fastener to a final desired stress value from an empirically determined stress rate above the region 0.1-0.5 elastic limit; means controlled by the data processor for resuming tightening; and means responsive to the value of the tightening parameter for terminating

Claim 27

tightening adjacent the final desired value. 28. The apparatus of claim 27 further comprising means for calculating the amount of tool overrun adjacent the final desired stress value and wherein the tightening terminating means comprises means responsive to the value of the tightening parameter and the amount of tool overrun for terminating

Claim 28

tightening adjacent the final desired stress value. 29. The apparatus of claim 27 wherein the means for calculating the tightening parameter value comprises means for dividing the difference between the final desired stress value and the stress calculated at the location by the empirically

Claim 29

determined stress rate above the region 0.1-0.5 elastic limit. 30. The apparatus of claim 27 wherein the means for calculating the tightening parameter value comprises means for dividing the difference between the final desired stress value and the stress at an angular position adjacent the location by the empirically determined stress rate above the region

Claim 30

1-0.5 elastic limit. 31. The apparatus of claim 27 wherein the

Claim 31

tightening parameter is in units of angle. 32. The apparatus of claim 27

Claim 32

wherein the tightening parameter is in units of torque. 33. The apparatus of claim 27 wherein the torque rate calculating means includes means for storing and recalling the sensed values of torque and angle and means for

Claim 33

determining an average torque rate from the sensings. 34. A method of tightening a joint including a threaded fastener, comprising tightening the fastener; sensing torque applied to the fastener and the angle of threading advance; determining, during tightening, the origin of stress in the fastener from the sensed values of torque and angle; determining a shut off parameter based on the origin of stress; and

Claim 34

determining an average torque rate from the sensings. 34. A method of tightening a joint including a threaded fastener, comprising tightening the fastener; sensing torque applied to the fastener and the angle of threading advance; determining, during tightening, the origin of stress in the fastener from the sensed values of torque and angle; determining a shut off parameter based on the origin of stress; and

Claim 35

terminating tightening in response to the shut off parameter. 35. Apparatus for tightening a joint including a threaded fastener, comprising a powered tool for tightening the fastener; means for sensing the torque applied to the fastener and the angle of threading advance; means for determining, during tightening, the origin of stress in the fastener pair from sensed values of torque and angle; means for determining, during tightening, a shut off parameter based on the origin of stress; and means for terminating operation of the powered tool in response to the shut

Claim 36

terminating tightening in response to the shut off parameter. 35. Apparatus for tightening a joint including a threaded fastener, comprising a powered tool for tightening the fastener; means for sensing the torque applied to the fastener and the angle of threading advance; means for determining, during tightening, the origin of stress in the fastener pair from sensed values of torque and angle; means for determining, during tightening, a shut off parameter based on the origin of stress; and means for terminating operation of the powered tool in response to the shut

Claim 37

off parameter. 36. A method of tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising empirically determining, prior to tightening the production joints, at least one joint characteristic; applying torque to the fastener for tightening the production joint; determining, while tightening below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress, a tightening parameter based on the empirically determined joint characteristic, which tightening parameter varies from one joint to the next; and

Claim 38

off parameter. 36. A method of tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising empirically determining, prior to tightening the production joints, at least one joint characteristic; applying torque to the fastener for tightening the production joint; determining, while tightening below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress, a tightening parameter based on the empirically determined joint characteristic, which tightening parameter varies from one joint to the next; and

Claim 39

terminating tightening in response to the tightening parameter. 37. The method of claim 36 wherein the empirically determined joint characteristic

Claim 40

is the fastener tension rate. 38. The method of claim 36 wherein the

Claim 41

empirically determined joint characteristic is the offset torque. 39. Apparatus for tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener and having at least one empirically determinable joint characteristic, comprising means for applying torque to the fastener; means for determining, while tightening below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress, a tightening parameter based on the empirically determined joint characteristic, which tightening parameter varies from one joint to the next, including means for delivering a signal to the determining means representative of the empirically determinable joint characteristic; and means for terminating tightening in response to the tightening parameter.

Claim 42

empirically determined joint characteristic is the offset torque. 39. Apparatus for tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener and having at least one empirically determinable joint characteristic, comprising means for applying torque to the fastener; means for determining, while tightening below the yield point of .[.any.]. .Iadd.all .Iaddend.joint .[.component.]. .Iadd.components .Iaddend.that can be correlated with stress, a tightening parameter based on the empirically determined joint characteristic, which tightening parameter varies from one joint to the next, including means for delivering a signal to the determining means representative of the empirically determinable joint characteristic; and means for terminating tightening in response to the tightening parameter.

Claim 43

. A method of tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising determining, prior to tightening the production joints, at least one tightening tool characteristic; applying torque to the fastener with the tightening tool for tightening the production joint; determining, while tightening, a tightening parameter based on the determined tool characteristic, which tightening parameter varies from one joint to the next; and

Claim 44

. A method of tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising determining, prior to tightening the production joints, at least one tightening tool characteristic; applying torque to the fastener with the tightening tool for tightening the production joint; determining, while tightening, a tightening parameter based on the determined tool characteristic, which tightening parameter varies from one joint to the next; and

Claim 45

terminating tightening in response to the tightening parameter. 41. The method of claim 40 wherein the determined tool characteristic is a

Claim 46

function of tool overrun. 42. The method of claim 41 wherein the

Claim 47

tightening tool characteristic is the stall torque of the tool. 43. The method of claim 41 wherein the tightening tool characteristic is the angle

Claim 48

overrun of the tightening tool under no torque conditions. 44. Apparatus for tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising a tightening tool for applying torque to the fastener; means for determining, while tightening, a tightening parameter based on a tool characteristic, which tightening parameter varies from one joint to the next, including means for delivering a signal to the determining means representative of the determined tool characteristic; and means for terminating tightening in response to the tightening parameter.

Claim 49

overrun of the tightening tool under no torque conditions. 44. Apparatus for tightening seriatim a multiplicity of substantially identical production joints including at least one threaded fastener, comprising a tightening tool for applying torque to the fastener; means for determining, while tightening, a tightening parameter based on a tool characteristic, which tightening parameter varies from one joint to the next, including means for delivering a signal to the determining means representative of the determined tool characteristic; and means for terminating tightening in response to the tightening parameter.

Claim 50

.Iadd.45. The method of claim 57 wherein said joint characteristic is determined from one or more actual, representative joints. .Iaddend. .Iadd.46. The method of claim 57 wherein the joint characteristic is

Claim 51

proportional to the joint tension rate. .Iaddend. .Iadd.47. The apparatus of claim 58 wherein the joint characteristic is proportional to the joint tension rate. .Iaddend. .Iadd.48. The apparatus of claim 58 further comprising means for determining, after the onset of tightening, a parameter proportional to the torque rate of the fastener. .Iaddend. .Iadd.49. The apparatus of claim 58 wherein the determining means comprises means for combining the determinable joint characteristic and the torque rate proportional parameter. .Iaddend. .Iadd.50. The apparatus of claim 58 wherein the determinable joint characteristic is the joint tension rate, said apparatus further comprising means for determining, after the onset of tightening, the torque rate of the fastener and the determining means comprising means for combining the joint tension rate

Claim 52

and the determined torque rate. .Iaddend. .Iadd.51. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired atress value below the yield point of all joint components that can be correlated with stress, including: tightening the fastener with an instructable tool; sensing torque at various angles of advance during tightening below the yield point of all joint components that can be correlated with stress; calculating, while tightening below the yield point of all joint components that can be correlated with stress, the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the sensed values of torque and angle; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener to the determined parameter; and terminating tightening in response to the attainment of the determined parameter. .Iaddend. .Iadd.52. Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value below the yield point, comprising: a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening below the yield point of all joint components that can be correlated with stress; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the sensed values of torque and angle; means for determining a tightening parameter value sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; and means for instructing the tool to tighten the fastener to the determined parameter value. .Iaddend. .Iadd.53. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of all joint components that can be correlated with stress, comprising: tightening the fastener with an instructable powered tool; sensing torque at various angles of advance during tightening; determining the torque rate of the fastener from the sensed values of torque and angle; calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the determined torque rate and from sensed torque; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener in response to the determined parameter; and terminating tightening in response to the determined parameter. .Iaddend.

Claim 53

and the determined torque rate. .Iaddend. .Iadd.51. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired atress value below the yield point of all joint components that can be correlated with stress, including: tightening the fastener with an instructable tool; sensing torque at various angles of advance during tightening below the yield point of all joint components that can be correlated with stress; calculating, while tightening below the yield point of all joint components that can be correlated with stress, the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the sensed values of torque and angle; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener to the determined parameter; and terminating tightening in response to the attainment of the determined parameter. .Iaddend. .Iadd.52. Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value below the yield point, comprising: a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening below the yield point of all joint components that can be correlated with stress; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the sensed values of torque and angle; means for determining a tightening parameter value sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; and means for instructing the tool to tighten the fastener to the determined parameter value. .Iaddend. .Iadd.53. A method of tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of all joint components that can be correlated with stress, comprising: tightening the fastener with an instructable powered tool; sensing torque at various angles of advance during tightening; determining the torque rate of the fastener from the sensed values of torque and angle; calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the determined torque rate and from sensed torque; determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress from the calculated stress; instructing the tool to tighten the fastener in response to the determined parameter; and terminating tightening in response to the determined parameter. .Iaddend.

Claim 54

.Iadd.54. Apparatus for tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of all joint components that can be correlated with stress, comprising: a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening; means for determining the torque rate of the fastener from the sensed values of torque and angle; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the determined torque rate and the sensed torque; means for determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress; and means for instructing the tool to tighten the fastener in response to the

Claim 55

.Iadd.54. Apparatus for tightening a multiplicity of substantially identical joints having components including at least one threaded fastener to a final desired stress value below the yield point of all joint components that can be correlated with stress, comprising: a powered instructable tool for tightening the fastener; means for sensing torque at various angles of advance during tightening; means for determining the torque rate of the fastener from the sensed values of torque and angle; means for calculating the stress appearing in the fastener at least at one instant of tightening below the yield point of all joint components that can be correlated with stress from the determined torque rate and the sensed torque; means for determining the value of a tightening parameter sufficient to tighten the fastener to the final desired stress value below the yield point of all joint components that can be correlated with stress; and means for instructing the tool to tighten the fastener in response to the

Claim 56

determined parameter. .Iaddend. .Iadd.55. Apparatus for tightening a threaded fastener in a joint including the fastener, the apparatus comprising: a tightening tool for imparting input characteristics including torque and rotation to the fastener to tighten the fastener, the tool being capable of terminating the tightening of the fastener in response to an instruction incorporating a directly measurable tightening related parameter which can vary from one to another of ostensibly alike joints in tightening fasteners therein to the same final tension; means for sensing at least one of the input characteristics; means for determining from the sensed input characteristics, after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, that value of the tightening related parameter which is representative of the amount of tightening required to tighten the fastener to the selected final tension; and means for transmitting to the tool an instruction that will cause the tool to terminate the tightening of the fastener in response to the reaching of the determined value of the tightening related parameter. .Iaddend. .Iadd.56. Apparatus for tightening a threaded fastener in a joint including the fastener, comprising: a power instructable tool, capable of terminating tightening in response to an instruction which varies from one fastener to the next, for imparting input characteristics including torque and rotation to the fastener; means for sensing at least one of the input characteristics; means responsive to the sensing means for determining after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, a tightening parameter value, variable from one fastener to the next, sufficient to tighten each fastener to the same final desired stress value; and means for terminating tightening of the fastener in response to the determined tightening parameter value. .Iaddend. .Iadd.57. A method of tightening a threaded fastener in a joint including the threaded fastener, comprising: determining, prior to tightening the fastener, at least one joint characteristic; applying torque to the fastener for tightening the same; determining, after the onset of tightening and while below the yield point of all joint components which can be correlated with stress, a tightening parameter based on the determined joint characteristic, which tightening parameter varies from one joint to the next; and terminating tightening in response to the tightening parameter. .Iaddend.

Claim 57

determined parameter. .Iaddend. .Iadd.55. Apparatus for tightening a threaded fastener in a joint including the fastener, the apparatus comprising: a tightening tool for imparting input characteristics including torque and rotation to the fastener to tighten the fastener, the tool being capable of terminating the tightening of the fastener in response to an instruction incorporating a directly measurable tightening related parameter which can vary from one to another of ostensibly alike joints in tightening fasteners therein to the same final tension; means for sensing at least one of the input characteristics; means for determining from the sensed input characteristics, after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, that value of the tightening related parameter which is representative of the amount of tightening required to tighten the fastener to the selected final tension; and means for transmitting to the tool an instruction that will cause the tool to terminate the tightening of the fastener in response to the reaching of the determined value of the tightening related parameter. .Iaddend. .Iadd.56. Apparatus for tightening a threaded fastener in a joint including the fastener, comprising: a power instructable tool, capable of terminating tightening in response to an instruction which varies from one fastener to the next, for imparting input characteristics including torque and rotation to the fastener; means for sensing at least one of the input characteristics; means responsive to the sensing means for determining after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, a tightening parameter value, variable from one fastener to the next, sufficient to tighten each fastener to the same final desired stress value; and means for terminating tightening of the fastener in response to the determined tightening parameter value. .Iaddend. .Iadd.57. A method of tightening a threaded fastener in a joint including the threaded fastener, comprising: determining, prior to tightening the fastener, at least one joint characteristic; applying torque to the fastener for tightening the same; determining, after the onset of tightening and while below the yield point of all joint components which can be correlated with stress, a tightening parameter based on the determined joint characteristic, which tightening parameter varies from one joint to the next; and terminating tightening in response to the tightening parameter. .Iaddend.

Claim 58

.Iadd.58. Apparatus for tightening a threaded fastener in a joint including the fastener and having a determinable joint characteristic, comprising: means for applying torque to the fastener; means for determining, after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, a tightening parameter based on the joint characteristic, which tightening parameter varies from one joint to the next; and means for terminating tightening in response to the tightening parameter.

Claim 59

.Iadd.58. Apparatus for tightening a threaded fastener in a joint including the fastener and having a determinable joint characteristic, comprising: means for applying torque to the fastener; means for determining, after the onset of tightening and while below the yield point of all joint components that can be correlated with stress, a tightening parameter based on the joint characteristic, which tightening parameter varies from one joint to the next; and means for terminating tightening in response to the tightening parameter.

Claim 60

.Iaddend. .Iadd.59. Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value, below the yield point of all components that can be correlated with stress, appearing in the fastener, comprising a powered instructable tool, capable of terminating tightening in response to an instruction which varies from one fastener to the next, for applying torque to the fastener and tightening the same; means for sensing the torque applied to the fastener at various angles of advance; means responsive to the torque and angle sensings for determining, while tightening at a value below which any of the aforesaid joint components are alterable in configuration by the application of a load thereto, a tightening parameter value, variable from one fastener to the next, sufficient to tighten each fastener to the final desired stress value; and means for instructing the tool to terminate tightening of each fastener in response to the determined tightening parameter value. .Iaddend.

Claim 61

.Iaddend. .Iadd.59. Apparatus for tightening seriatim a multiplicity of substantially identical joints having components including at least one threaded fastener to substantially the same final desired stress value, below the yield point of all components that can be correlated with stress, appearing in the fastener, comprising a powered instructable tool, capable of terminating tightening in response to an instruction which varies from one fastener to the next, for applying torque to the fastener and tightening the same; means for sensing the torque applied to the fastener at various angles of advance; means responsive to the torque and angle sensings for determining, while tightening at a value below which any of the aforesaid joint components are alterable in configuration by the application of a load thereto, a tightening parameter value, variable from one fastener to the next, sufficient to tighten each fastener to the final desired stress value; and means for instructing the tool to terminate tightening of each fastener in response to the determined tightening parameter value. .Iaddend.