Selectively-controlled well bore apparatus

Claim 2

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said body means and adapted to be alternatively rotated in opposite rotational directions; tool-positioning means including a tool-positioning member cooperatively arranged on said body means and adapted for free movement back and forth between a retracted position and an extended wall-engaging position; and means cooperatively arranged on said body means for controlling the movement of said tool-positioning member and including coupling means operable in response to rotation of said shaft member in one of said rotational directions for uncoupling said members so as to then release said tool-positioning member for its said free movement and operable in response to rotation of said shaft member in the other of said rotational directions for releasably intercoupling said members so as to then return said tool-positioning member to its said retracted position, said coupling means having means operable upon return of said tool-positioning member to its said retracted position for selectively restraining retrograde movement of said tool-positioning member toward its said extended position and releasable only upon rotation of said shaft member in said one rotational direction to leave said tool-positioning member free for movement between its said extended and retracted positions.

Claim 3

The well bore apparatus of claim 1 wherein said tool-positioning means further include: spring means cooperatively arranged and adapted to be at least further energized upon movement of said tool-positioning member toward its said retracted position for urging said tool-positioning member outwardly toward its said extended position with a predetermined biasing force commensurate with the degree of energization of said spring means.

Claim 4

The well bore apparatus of claim 1 wherein said tool-positioning means further include: spring means cooperatively mounted between said body means and said tool-positioning member and adapted to be energized upon its movement toward its said retracted position by the driving of said shaft member in said other rotational direction, said spring means being operable whenever said members are uncoupled for urging said tool-positioning member toward its said extended position with a biasing force commensurate with the degree of energization of said spring means.

Claim 5

The well bore apparatus of claim 1 wherein said means for selectively restraining retrograde movement comprises ratchet means selectively engageable with said shaft member as it is being driven in said other rotational direction for releasably preventing retrograde rotation of said shaft member in said one rotational direction and selectively releasable in response to the driving of said shaft member in said one rotational direction.

Claim 6

The well bore apparatus of claim 4 wherein said tool-positioning means further include: spring means cooperatively mounted between said body means and said tool-positioning member and adapted to be energized upon return thereof toward its said retracted position and then effective upon uncoupling of said members for urging said tool-positioning member toward its said extended position with a predetermined biasing force selected to move said tool-positioning member outwardly at a controlled speed of travel.

Claim 7

The well bore apparatus of claim 5 wherein said biasing force provided by said spring means is selected so that return of said tool-positioning member toward its said extended position is at a lower travel speed than said controlled speed of travel as said tool-positioning member is being moved toward its said extended position by said biasing force.

Claim 8

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said body means and adapted to be alternatively rotated in opposite rotational directions; tool-positioning means including a tool-positioning member cooperatively arranged on said body means and adapted for free movement back and forth between a retracted position and an extended wall-engaging position; means cooperatively arranged on said body means for controlling the movement of said tool-positioning member and including coupling means operable in response to rotation of said shaft member in one of said rotational directions for uncoupling said members so as to then release said tool-positioning member for its said free movement and operable in response to rotation of said shaft member in the other of said rotational directions for releasably intercoupling said members so as to then return said tool-positioning member to its said retracted position, said coupling means having means operable upon rotation of said shaft member in said other rotational direction for selectively preventing counter-rotation of said shaft member in said one rotational direction and selectively releasable only upon rotation of said shaft member in said one rotational direction for freeing said tool-positioning member for movement toward its said extended position.

Claim 9

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said body means and adapted to be alternatively rotated in opposite rotational directions; tool-positioning means including a tool-positioning member cooperatively arranged on said body means and adapted for free movement back and forth between a retracted position and an extended wall-engaging position; means cooperatively arranged on said body means for controlling the movement of said tool-positioning member and including coupling means operable in response to rotation of said shaft member in one of said rotational directions for uncoupling said members so as to then release said tool-positioning member for its said free movement and operable in response to rotation of said shaft member in the other of said rotational directions for releasably intercoupling said members so as to then return said tool-positioning member to its said retracted position, said coupling means having means operable upon rotation of said shaft member in said other rotational direction for selectively preventing counter-rotation of said shaft member in said one rotational direction and selectively releasable only upon rotation of said shaft member in said one rotational direction for freeing said tool-positioning member for movement toward its said extended position.

Claim 10

The well bore apparatus of claim 7 wherein said tool-positioning means further include: spring means cooperatively mounted between said body means and said tool-positioning member and adapted to be energized upon return of said tool-positioning member to its said retracted position to provide a predetermined biasing force effective upon release of said tool-positioning member for moving it toward its said extended position at a predetermined speed of travel which is faster than the speed at which said tool-positioning member is returned to its said retracted position.

Claim 11

The well bore apparatus according to any one of claims 1, 2, 7, 8, 3, 4, 5, or 6 wherein said driving means further include: a selectively-reversible electrical motor on said body means and cooperatively coupled to said shaft member for alternatively driving said shaft member in either of its said opposite rotational directions.

Claim 12

Well bore apparatus comprising: a tool body adapted for passage through a well bore; tool-positioning means including at least one wall-engaging member, means pivotally cnnecting said wall-engaging member to said tool body for pivotal movement between a retracted position adjacent to said tool body and an extended position spatially disposed away from said tool body, and spring means cooperatively associated with said wall-engaging member and adaptd to impose thereon a biasing force of predetermined magnitude selected for pivoting said wall-engaging member toward its said extended position at a predetermined speed of travel; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; and coupling means cooperatively arranged between said members operable upon rotation of said shaft member in one of said rotational directions for uncoupling said members so that only said spring means are then operative for moving said wall-engaging member toward its said extended position at said predetermined speed of travel and operable upon rotation of said shaft member in the other of said rotational directions for releasably intercoupling said members so as to return said wall-engaging member to its said retracted position at a speed of travel that is less than said predetermined speed of travel.

Claim 13

Well bore apparatus comprising: a tool body adapted for passage through a well bore; tool-positioning means including at least one wall-engaging member, means pivotally cnnecting said wall-engaging member to said tool body for pivotal movement between a retracted position adjacent to said tool body and an extended position spatially disposed away from said tool body, and spring means cooperatively associated with said wall-engaging member and adaptd to impose thereon a biasing force of predetermined magnitude selected for pivoting said wall-engaging member toward its said extended position at a predetermined speed of travel; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; and coupling means cooperatively arranged between said members operable upon rotation of said shaft member in one of said rotational directions for uncoupling said members so that only said spring means are then operative for moving said wall-engaging member toward its said extended position at said predetermined speed of travel and operable upon rotation of said shaft member in the other of said rotational directions for releasably intercoupling said members so as to return said wall-engaging member to its said retracted position at a speed of travel that is less than said predetermined speed of travel.

Claim 14

The well bore apparatus of claim 10 wherein said coupling means further include: means operable upon driving said shaft member in said other rotational direction for selectively preventing retrograde movement of said wall-engaging member toward its said extended position and operable upon driving of said shaft member in said one rotational direction to release said wall-engaging member for free movement between its said extended and retracted positions.

Claim 15

The well bore apparatus of claim 10 wherein said spring means include: at least one arcuately-configured leaf spring mounted between said tool body and said wall-engaging member and adapted to be at least further energized upon movement of said wall-engaging member toward its said retracted position for developing said biasing force commensurate with the degree of energization of said leaf spring to then urge said wall-engaging member toward its said extended position.

Claim 16

The well bore apparatus of claim 12 wherein said coupling means further include: means operable only upon driving of said shaft member in said other rotational direction for selectively halting retrograde movement of said wall-engaging member away from its retracted position and operable only upon driving of said shaft member in said one rotational direction for releasing said wall-engaging member for movement toward its said extended position in response to said biasing force.

Claim 17

The well bore apparatus of claim 10 wherein said coupling means further include: means operable upon rotation of said shaft member in said other rotational direction for selectively preventing counter rotation of said shaft member in said one rotational direction and selectively releasable only upon rotation of said shaft member in said one rotational direction for freeing said wall-engaging member for movement toward its said extended positions.

Claim 18

The well bore apparatus according to any one of claims 10, 11, 12, 13 or 14 wherein said driving means further include: a selectively-reversible electrical motor on said tool body and cooperatively arranged for alternatively driving said shaft member in either of its said rotational directions.

Claim 19

Well bore apparatus comprising: a tool body adapted for passage through a well bore; tool-positioning means including at least one wall-engaging member, means operatively connecting said wall-engaging member to said tool body for movement back and forth between retracted and extended positions, and spring means cooperatively arranged for acting on said wall-engaging member with a biasing force of predetermined magnitude selected for moving said wall-engaging member toward its said extended position at a predetermined speed of travel; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; and coupling means cooperatively arranged on said tool body for selectively intercoupling said members including a rotatable threaded shaft, a threaded body operatively mounted on said threaded shaft and co-rotatively secured in relation to said tool body for axial movement along said threaded shaft as it is rotated, force-transmitting means coupling said threaded body to said wall-engaging member and adapted for transferring forces therebetween, and clutch means operable in response to rotation of said shaft member in one of its said rotational directions for selectively uncoupling said shaft member from said threaded shaft so that said wall-engaging member will be released for movement toward its extended position at said predetermined speed of travel and remain free for movement back and forth between its said extended and retracted positions upon passage of said tool body along a well bore, said clutch means also being operable in response to rotation of said shaft member in the other of its said rotational directions for selectively intercoupling said shaft member to said threaded shaft so that the corresponding axial movement of said threaded body therealong will be effective for returning said wall-engaging member to its retracted position at a speed of travel less than said predetermined speed of travel.

Claim 20

Well bore apparatus comprising: a tool body adapted for passage through a well bore; tool-positioning means including at least one wall-engaging member, means operatively connecting said wall-engaging member to said tool body for movement back and forth between retracted and extended positions, and spring means cooperatively arranged for acting on said wall-engaging member with a biasing force of predetermined magnitude selected for moving said wall-engaging member toward its said extended position at a predetermined speed of travel; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; and coupling means cooperatively arranged on said tool body for selectively intercoupling said members including a rotatable threaded shaft, a threaded body operatively mounted on said threaded shaft and co-rotatively secured in relation to said tool body for axial movement along said threaded shaft as it is rotated, force-transmitting means coupling said threaded body to said wall-engaging member and adapted for transferring forces therebetween, and clutch means operable in response to rotation of said shaft member in one of its said rotational directions for selectively uncoupling said shaft member from said threaded shaft so that said wall-engaging member will be released for movement toward its extended position at said predetermined speed of travel and remain free for movement back and forth between its said extended and retracted positions upon passage of said tool body along a well bore, said clutch means also being operable in response to rotation of said shaft member in the other of its said rotational directions for selectively intercoupling said shaft member to said threaded shaft so that the corresponding axial movement of said threaded body therealong will be effective for returning said wall-engaging member to its retracted position at a speed of travel less than said predetermined speed of travel.

Claim 21

The well bore apparatus of claim 16 wherein said coupling means further include: ratchet means selectively engageable with said shaft member as it is being driven in said other rotational direction for releasably preventing retrograde rotation of said shaft member in said one rotational direction and selectively releasable in response to the driving of said shaft member in said one rotational direction.

Claim 22

The well bore apparatus of claim 16 wherein said clutch means include: a first clutch member coupled to said threaded shaft, a second clutch member cooperatively arranged for movement between two axially-spaced operating positions, and cam means operatively coupling said second clutch member to said shaft member and responsive to rotation thereof in said one rotational direction for axially shifting said second clutch member to one of its said operating positions where said clutch members are disengaged and responsive to rotation of said shaft member in said other rotational direction for axially shifting said second clutch member to the other of its said operating positions where said clutch members are drivingly engaged.

Claim 23

The well bore apparatus of claim 18 wherein said coupling means further include: ratchet means selectively engageable with said shaft member as it is being driven in said other rotational direction for releasably preventing retrograde rotation of said shaft member in said one rotational direction when said clutch members are drivingly engaged and selectively releasable in response to the driving of said shaft member in said one rotational direction when said clutch members are disengaged.

Claim 24

The well bore apparatus according to any one of claims 16, 17, 18 or 19 wherein said driving means further include: a selectively-reversible electrical motor on said tool body and cooperatively coupled to said shaft member for alternatively driving said shaft member in its said opposite rotational directions.

Claim 25

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means on said body means and adapted for alternative rotation in opposite rotational directions; tool-positioning means including a plurality of wall-engaging members cooperatively arranged at uniformly-spaced intervals around said body means and respectively adapted for movement between retracted positions adjacent to said body means and extended positions spaced outwardly from said body means; means cooperatively arranged on said body means for selectively controlling the movements of said wall-engaging members between their said retracted and extended positions and including coupling means between said wall-engaging members and said driving means operable in response to rotation of said driving means in one of said rotational for selectively uncoupling said driving means from said wall-engaging members so that they will be freed for movement between their said extended and retracted positions in response to passage of said body means along a well bore and operable in response to rotation thereof in the other of said rotational directions for selectively intercoupling said driving means to said wall-engaging members so as to bring them toward their said retracted positions; electrical transducer means on said body means and having a selectively-variable electrical characteristic; and transducer-actuating means coupled to at least one of said wall-engaging members and operable upon movement thereof for proportionally varying said electrical characteristic as a function of well bore diameter.

Claim 26

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means on said body means and adapted for alternative rotation in opposite rotational directions; tool-positioning means including a plurality of wall-engaging members cooperatively arranged at uniformly-spaced intervals around said body means and respectively adapted for movement between retracted positions adjacent to said body means and extended positions spaced outwardly from said body means; means cooperatively arranged on said body means for selectively controlling the movements of said wall-engaging members between their said retracted and extended positions and including coupling means between said wall-engaging members and said driving means operable in response to rotation of said driving means in one of said rotational for selectively uncoupling said driving means from said wall-engaging members so that they will be freed for movement between their said extended and retracted positions in response to passage of said body means along a well bore and operable in response to rotation thereof in the other of said rotational directions for selectively intercoupling said driving means to said wall-engaging members so as to bring them toward their said retracted positions; electrical transducer means on said body means and having a selectively-variable electrical characteristic; and transducer-actuating means coupled to at least one of said wall-engaging members and operable upon movement thereof for proportionally varying said electrical characteristic as a function of well bore diameter.

Claim 27

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means on said body means and adapted for alternative rotation in opposite rotational directions; tool-positioning means including a plurality of wall-engaging members cooperatively arranged at uniformly-spaced intervals around said body means and respectively adapted for movement between retracted positions adjacent to said body means and extended positions spaced outwardly from said body means; means cooperatively arranged on said body means for selectively controlling the movements of said wall-engaging members between their said retracted and extended positions and including coupling means between said wall-engaging members and said driving means operable in response to rotation of said driving means in one of said rotational directions for seletively uncoupling said driving means from said wall-engaging members so that they will be freed for movement between their said extended and retracted positions in response to passage of said body means along a well bore and operable in response to rotation thereof in the other of said rotational directions for selectively intercoupling said driving means to said wall-engaging members so as to bring them towards their said retracted positions; first and second electrical trnsducer means on said body means and respectively having first and second selectively-variable electrical characteristics; and first and second transducer-actuating means respectively coupled to a first one and to a second one of said wall-engaging members and selectively operable upon their respective movements for proportionally varying said first electrical characteristic as a function of well bore diameter in the plane of movement of said first wall-engaging member and for proportionally varying said second electrical characteristic as a function of well bore diameter in the plane of movement of said second wall-engaging member.

Claim 28

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means on said body means and adapted for alternative rotation in opposite rotational directions; tool-positioning means including a plurality of wall-engaging members cooperatively arranged at uniformly-spaced intervals around said body means and respectively adapted for movement between retracted positions adjacent to said body means and extended positions spaced outwardly from said body means; means cooperatively arranged on said body means for selectively controlling the movements of said wall-engaging members between their said retracted and extended positions and including coupling means between said wall-engaging members and said driving means operable in response to rotation of said driving means in one of said rotational directions for seletively uncoupling said driving means from said wall-engaging members so that they will be freed for movement between their said extended and retracted positions in response to passage of said body means along a well bore and operable in response to rotation thereof in the other of said rotational directions for selectively intercoupling said driving means to said wall-engaging members so as to bring them towards their said retracted positions; first and second electrical trnsducer means on said body means and respectively having first and second selectively-variable electrical characteristics; and first and second transducer-actuating means respectively coupled to a first one and to a second one of said wall-engaging members and selectively operable upon their respective movements for proportionally varying said first electrical characteristic as a function of well bore diameter in the plane of movement of said first wall-engaging member and for proportionally varying said second electrical characteristic as a function of well bore diameter in the plane of movement of said second wall-engaging member.

Claim 29

The well bore apparatus of claim 22 wherein said plane of movement of said first wall-engaging members lies substantially at right angles to said plane of movement of said second wall-engaging member.

Claim 30

The well bore apparatus according to any one of claims 21, 22 or 23 wherein said tool-positioning means further include: spring means cooperatively arranged and adapted to be at least further energized upon inward movement of said wall-engaging members toward their said retracted positions for urging said wall-engaging members outwardly toward their said extended positions with a biasing force commensurate with the degree of energization of said spring means.

Claim 31

The well bore apparatus of claim 24 wherein said driving means further include: a selectively-reversible electrical motor operatively arranged to be alternatively rotated in said opposite rotational directions.

Claim 32

The well bore apparatus according to any one of claims 21, 22 or 23 wherein said wall-engaging members are rigid arms and said tool-positioning means further include: means pivotally connecting each of said rigid arms to said body means, and spring means cooperatively arranged and adapted to be at least further energized upon pivotal movement of said rigid arms toward their said retracted positions.

Claim 33

The well bore apparatus of claim 26 wherein said driving means further include: a selectively-reversible electrical motor operatively arranged to be alternatively rotated in said opposite rotational directions.

Claim 34

The well bore apparatus according to any one of claims 21, 22 or 23 wherein said driving means further include: a selectively-reversible electrical motor operatively arranged to be alternatively rotated in said opposite rotational directions.

Claim 35

Well bore apparatus comprising: a tool body adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; tool-positioning means including a first pair of wall-engaging means on diametrically-opposite first sides of said tool body and pivotally coupled thereto for pivotal movement between retracted positions and extended positions lying in a first plane of movement, a second pair of wall-engaging means on diametrically-opposite second sides of said tool body and pivotally coupled thereto for pivotal movement between retracted and extended positions lying in a second plane of movement substantially perpendicularly intersecting said first plane of movement along the longitudinal axis of said tool body, and first and second spring means cooperatively arranged and adapted for respectively urging said first and second pairs of wall-engaging means toward their said extended positions at predetermined speeds of travel; and means cooperatively arranged on said tool body for selectively controlling the independent movements of said first and second pairs of wall-engaging means between their said retracted and extended positions and including coupling means cooperatively arranged on said tool body for selectively intercoupling said shaft member to said first and second pairs of wall-engaging means including a rotatable threaded shaft, a threaded body operatively mounted on said threaded shaft and co-rotatively secured in relation to said tool body for producing axial movement of said threaded body along said threaded shaft as it is rotated, force-transmitting means coupling said threaded body to said first and second pairs of wall-engaging means, and clutch means selectively operable upon rotation of said shaft member in one of its said rotational directions for uncoupling said shaft member from said threaded shaft so that said first and second pairs of wall-engaging means will be released for movement toward their extended positions at their respective predetermined speeds of travel and be freed for movement back and forth between their said extended and retracted positions upon passage of said tool body along a well bore, said clutch means also being selectively operable upon rotation of said shaft member in the other of its said rotational directions for releasably coupling said shaft member to said threaded shaft so that upon its rotation the corresponding axial movement of said threaded body therealong will be effective for returning said first and second pairs of wall-engaging means to their said retracted positions.

Claim 36

Well bore apparatus comprising: a tool body adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said tool body and adapted to be alternatively driven in opposite rotational directions; tool-positioning means including a first pair of wall-engaging means on diametrically-opposite first sides of said tool body and pivotally coupled thereto for pivotal movement between retracted positions and extended positions lying in a first plane of movement, a second pair of wall-engaging means on diametrically-opposite second sides of said tool body and pivotally coupled thereto for pivotal movement between retracted and extended positions lying in a second plane of movement substantially perpendicularly intersecting said first plane of movement along the longitudinal axis of said tool body, and first and second spring means cooperatively arranged and adapted for respectively urging said first and second pairs of wall-engaging means toward their said extended positions at predetermined speeds of travel; and means cooperatively arranged on said tool body for selectively controlling the independent movements of said first and second pairs of wall-engaging means between their said retracted and extended positions and including coupling means cooperatively arranged on said tool body for selectively intercoupling said shaft member to said first and second pairs of wall-engaging means including a rotatable threaded shaft, a threaded body operatively mounted on said threaded shaft and co-rotatively secured in relation to said tool body for producing axial movement of said threaded body along said threaded shaft as it is rotated, force-transmitting means coupling said threaded body to said first and second pairs of wall-engaging means, and clutch means selectively operable upon rotation of said shaft member in one of its said rotational directions for uncoupling said shaft member from said threaded shaft so that said first and second pairs of wall-engaging means will be released for movement toward their extended positions at their respective predetermined speeds of travel and be freed for movement back and forth between their said extended and retracted positions upon passage of said tool body along a well bore, said clutch means also being selectively operable upon rotation of said shaft member in the other of its said rotational directions for releasably coupling said shaft member to said threaded shaft so that upon its rotation the corresponding axial movement of said threaded body therealong will be effective for returning said first and second pairs of wall-engaging means to their said retracted positions.

Claim 37

The well bore apparatus of claim 29 wherein said coupling means further include: ratchet means selectively engageable with said shaft member as it is being driven in said other rotational direction for releasably preventing retrograde rotation of said shaft member in said one rotational direction and selectively releasable in response to the driving of said shaft member in said one rotational direction.

Claim 38

The well bore apparatus of claim 29 wherein said clutch means include: a first clutch member coupled to said threaded shaft, a second clutch member cooperatively arranged for movement between axially-spaced positions, and means operatively coupling said second clutch member to said shaft member and responsive to rotation thereof in said one rotational direction for shifting said second clutch member to one of its said axial positions where said clutch members are disengaged and responsive to rotation of said shaft member in said other rotational direction for shifting said second clutch member to the other of its said axial positions where said clutch members are drivingly engaged.

Claim 39

The well bore apparatus of claim 31 wherein said coupling means further include: ratchet means selectively engageable with said shaft member as it is being driven in said other rotational direction for releasably preventing retrograde rotation of said shaft member in said one rotational direction when said clutch members are drivingly engaged and selectively releasable in response to the driving of said shaft member in said one rotational direction when said clutch members are disengaged.

Claim 40

The well bore apparatus of claim 29 further including: first and second electrical transducer means on said tool body and respectively having first and second selectively-variable electrical characteristics; and first and second transducer-actuating means respectively coupled to said first and second pairs of wall-engaging means and selectively operable upon their respective movements for proportionally varying said first and second electrical characteristics respectively as a function of well bore diameter in said first plane of movement and as a function of well bore diameter in said second plane of movement.

Claim 41

The well bore apparatus of claim 29 wherein said first and second pairs of wall-engaging means include first and second pairs of rigid arms; and said first and second spring means are respectively cooperatively arranged between said rigid members and said tool body to be at least further energized upon movement of said rigid members toward their said retracted positions.

Claim 42

The well bore apparatus according to any one of claims 29, 30, 31, 32, 33 or 34 wherein said driving means further include: a selectively-reversible electrical motor operatively coupled to said shaft member for alternatively driving it in its said opposite rotational directions.

Claim 43

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said body means and adapted to be selectively rotated in opposite rotational directions or to remain stationary; tool-positioning means including a tool-positioning member cooperatively arranged on said body means and adapted for free movement between a retracted position and an extended wall-engaging position; coupling means cooperatively arranged on said body means between said driving means and said tool-positioning means for releasing said tool-positioning means for its free movement in response to rotation of said shaft member in a first direction; retracting said tool-positioning means to said retracted position in response to rotation of said shaft member in the second other direction; and preventing said tool-positioning means from moving from its retracted position until said shaft member is rotated in said first direction.

Claim 44

Well bore apparatus comprising: body means adapted for passage through a well bore; driving means including a shaft member cooperatively arranged on said body means and adapted to be selectively rotated in opposite rotational directions or to remain stationary; tool-positioning means including a tool-positioning member cooperatively arranged on said body means and adapted for free movement between a retracted position and an extended wall-engaging position; coupling means cooperatively arranged on said body means between said driving means and said tool-positioning means for releasing said tool-positioning means for its free movement in response to rotation of said shaft member in a first direction; retracting said tool-positioning means to said retracted position in response to rotation of said shaft member in the second other direction; and preventing said tool-positioning means from moving from its retracted position until said shaft member is rotated in said first direction.