Formation-testing tool for obtaining multiple measurements and fluid samples

Claim 2

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage adapted to receive connate fluids; fluid-admitting means on said body and adapted to be selectively engaged with a well bore wall for isolating a portion thereof from well bore fluids; first pressure-responsive means on said body and operable in response to a first operating pressure of a selected magnitude for moving said fluid-admitting means against a well bore wall to establish communication with earth formations therebeyond; second pressure-responsive means on said body and operable in response to a second operating pressure of a selected different magnitude for communicating said fluid passage with said fluidadmitting means; and means on said body coupled to said first and second pressureresponsive means and selectively operable for successively developing at least said first and second operating pressures in turn to operate said first and second pressure-responsive means in a predetermined sequence.

Claim 3

The formation-testing apparatus of claim 1 wherein said second operating pressure is greater than said first operating pressure.

Claim 4

The formation-testing apparatus of claim 1 further including transducer means on said body and in communication with said fluid passage for measuring at least one characteristic of connate fluids.

Claim 5

The formation-testing apparatus of claim 3 wherein said transducer means include a pressure-measuring transducer.

Claim 6

The formation-testing apparatus of claim 1 further including: means on said body defining a fluid-receiving chamber; and third pressure-responsive means coupled to said motive means and operable in response to a third operating pressure of a selected magnitude developed by said motive means and different than said first and second operating pressures for communicating said fluid passage with said fluid-receiving chamber.

Claim 7

The formation-testing apparatus of claim 5 wherein said second operating pressure is greater than said first operating pressure, and said third operating pressure is greater than said second operating pressure.

Claim 8

The formation-testing apparatus of claim 5 further including transducer means on said body and in communication with said fluid passage for measuring at least one characteristic of connate fluids entering said fluid passage and said fluid-receiving chamber.

Claim 9

The formation-testing apparatus of claim 7 wherein said transducer means include a pressure-measuring transducer.

Claim 10

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage adapted to receive connate fluids; fluid-admitting means on said body and adapted to be selectively engaged with a well bore wall for isolating a portion thereof from well bore fluids; actuating means on said body and adapted for supplying an actuating fluid at a range of varying output pressures; first pressure-responsive means on said body operable in response to a first predetermined pressure for selectively placing said fluid-admitting means against a well bore wall to establish communication with earth formations therebeyond and operable in response to a fourth predetermined pressure for selectively displacing said fluid-admitting means from a well bore wall to discontinue such communication; second pressure-responsive means on said body operable in response to a second predetermined pressure for selectively communicating said fluid-admitting means with said fluid passage and operable in response to a third predetermined pressure for selectively discontinuing communication between said fluid-admitting means and said fluid passage; and control means selectively operable from the surface for communicating an actuating fluid from said actuating means wiTh each of said pressure-responsive means to sequentially place said fluid-admitting means against a well bore wall, communicate and then discontinue communication between said fluid-admitting means and said fluid passage, and finally displace said fluid-admitting means from a well bore wall in response to successive changes of said output pressures of said actuating means to each of said predetermined pressures in turn.

Claim 11

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage adapted to receive connate fluids; fluid-admitting means on said body and adapted to be selectively engaged with a well bore wall for isolating a portion thereof from well bore fluids; actuating means on said body and adapted for supplying an actuating fluid at a range of varying output pressures; first pressure-responsive means on said body operable in response to a first predetermined pressure for selectively placing said fluid-admitting means against a well bore wall to establish communication with earth formations therebeyond and operable in response to a fourth predetermined pressure for selectively displacing said fluid-admitting means from a well bore wall to discontinue such communication; second pressure-responsive means on said body operable in response to a second predetermined pressure for selectively communicating said fluid-admitting means with said fluid passage and operable in response to a third predetermined pressure for selectively discontinuing communication between said fluid-admitting means and said fluid passage; and control means selectively operable from the surface for communicating an actuating fluid from said actuating means wiTh each of said pressure-responsive means to sequentially place said fluid-admitting means against a well bore wall, communicate and then discontinue communication between said fluid-admitting means and said fluid passage, and finally displace said fluid-admitting means from a well bore wall in response to successive changes of said output pressures of said actuating means to each of said predetermined pressures in turn.

Claim 12

The formation-testing apparatus of claim 9 wherein said fourth predetermined pressure is greater than said first predetermined pressure.

Claim 13

The formation-testing apparatus of claim 9 wherein said third predetermined pressure is greater than said second predetermined pressure.

Claim 14

The formation-testing apparatus of claim 9 wherein said fourth and third predetermined pressures are respectively greater than said first and second predetermined pressures.

Claim 15

The formation-testing apparatus of claim 9 further including: sample-collecting means on said body and adapted for receiving a sample of connate fluids in said fluid passage; and third pressure-responsive means on said body operable in response to a fifth predetermined operating pressure for communicating said fluid passage with said sample-collecting means as said control means communicate an actuating fluid with said third pressure-responsive means and operable in response to a sixth predetermined operating pressure for discontinuing communication between said fluid passage and said sample-collecting means as said control means communicate an actuating fluid with said third pressure-responsive means.

Claim 16

The formation-testing apparatus of claim 13 wherein said control means further include: valve means on said body and selectively operable from the surface for controlling fluid communication between said third pressure-responsive means and said actuating means.

Claim 17

The formation-testing apparatus of claim 13 wherein said fifth predetermined pressure is greater than said fourth predetermined pressure and said fourth predetermined pressure is greater than said first predetermined pressure.

Claim 18

The formation-testing apparatus of claim 15 wherein said third predetermined pressure is greater than said second predetermined pressure and said second predetermined pressure is greater than said sixth predetermined pressure.

Claim 19

The formation-testing apparatus of claim 9 further including: pressure-measuring means cooperatively associated with said fluid passage and adapted for providing signals at the surface representative of pressures of fluids in said fluid passage.

Claim 20

The formation-testing apparatus of claim 9 wherein said first pressure-responsive means include: piston-actuator means on said body and including at least one piston member adapted for extension from said body upon application of said first predetermined pressure to said piston-actuator means and adapted for retraction away from a well bore wall upon application of said fourth predetermined pressure to said piston-actuator means.

Claim 21

The formation-testing apparatus of claim 18 further including: wall-engaging means coupled to said piston member and adapted for movement thereby into anchoring engagement with a well bore wall upon extension of said piston member from said body.

Claim 22

The formation-testing apparatus of claim 18 further including: means cooperatively coupling said fluid-admitting means to said piston member for movement thereby into engagement with a well bore wall upon extension of said piston member from said body.

Claim 23

The formation-testing apparatus of claim 9 wherein said first pressure-responsive means include: piston-actuator means on said body and including at least first and second piston members respectively adapted for extension in opposite directions from said body upon application of said first predetermined pressure to said piston-actuator means and respectively adapted for retraction back to said body upon application of said fourth preDetermined pressure to said piston-actuator means; wall-engaging means coupled to said first piston member and adapted for movement thereby into and out of anchoring engagement with a well bore wall upon extension and retraction of said first piston member; and means cooperatively coupling said fluid-admitting means to said second piston member for movement thereby into and out of engagement with a well bore wall upon extension and retraction of said second piston member.

Claim 24

The formation-testing apparatus of claim 21 further including: wall-sealing means cooperatively arranged on said fluid-admitting means and adapted for sealing engagement with a well bore wall upon extension of said second piston member.

Claim 25

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including first piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said first piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said first piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including valve means movable between open and closed operating positions and coupled to said fluid passage, and second piston means connected to said valve means and operatively arranged for selectively moving said valve means to one of said operating positions in response to a pressure differential acting on one end of said second piston means and for selectively moving said valve means to the other of said operating positions in response to a pressure differential acting on the other end of said second piston means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said first piston means, a second hydraulic conduit coupled to said other end of said first piston means and to said other end of said second piston means, and a third hydraulic conduit coupled to said one end of said second piston means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said first piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said first hydraulic conduit to said third hydraulic conduit to supply hydraulic fluid to said one end of said second piston means only so long as the fluid pressure in said first hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cycle of said pump for selectively coupling said second hydraulic conduit to said pump outlet and coupling said third hydraulic conduit to said pump inlut to supply hydraulic fluid at a second selected pressure level to said other end of said second piston means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 26

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including first piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said first piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said first piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including valve means movable between open and closed operating positions and coupled to said fluid passage, and second piston means connected to said valve means and operatively arranged for selectively moving said valve means to one of said operating positions in response to a pressure differential acting on one end of said second piston means and for selectively moving said valve means to the other of said operating positions in response to a pressure differential acting on the other end of said second piston means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said first piston means, a second hydraulic conduit coupled to said other end of said first piston means and to said other end of said second piston means, and a third hydraulic conduit coupled to said one end of said second piston means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said first piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said first hydraulic conduit to said third hydraulic conduit to supply hydraulic fluid to said one end of said second piston means only so long as the fluid pressure in said first hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cycle of said pump for selectively coupling said second hydraulic conduit to said pump outlet and coupling said third hydraulic conduit to said pump inlut to supply hydraulic fluid at a second selected pressure level to said other end of said second piston means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 27

The formation-testing apparatus of claim 23 wherein said one operating position of said valve means is said open position of said valve means.

Claim 28

The formation-testing apparatus of claim 23 wherein said one operating position of said valve means is said closed position of said valve means.

Claim 29

The formation-testing apparatus of claim 23 further including: control means selectively operable from the surface for controlling the admission of hydraulic fluid from said third hydraulic conduit to said one end of said second piston means.

Claim 30

The formation-testing apparatus of claim 23 further including: means cooperatively coupling said fluid-admitting means to said first piston means for moving said fluid-admitting means into and out of engagement with a well bore wall upon extension and retraction of said first piston means.

Claim 31

The formation-testing apparatus of claim 23 further including: sample-collecting means coupled to said fluid passage downstream of said valve means.

Claim 32

The formation-testing apparatus of claim 28 further including: control means selectively operable from the surface for controlling the admission of hydraulic fluid from said third hydraulic conduit to said one end of said second piston means.

Claim 33

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including first piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said first piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said first piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including valve means movable between open and closed operating positions and coupled to said fluid passage, and second piston means connected to said valve means and operatively arranged for selectively moving said valve means to one of said operating positions in response to a pressure differential acting on one end of said second piston means and for selectively moving said valve means to the other of said operating positions in response to a pressure differential acting on the other end of said second piston means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said first piston means and to said one end of said second piston means, and a second hydraulic conduit coupled to said other end of said first piston means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said first piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said second hydraulic conduit to said other end of said second piston means to receive hydraulic fluid therefrom only so long as the fluid pressure in said firsT hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cyle of said pump for selectively coupling said second hydraulic conduit to said pump outlet to supply hydraulic fluid at a second preselected pressure level to said other end of said second piston means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 34

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including first piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said first piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said first piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including valve means movable between open and closed operating positions and coupled to said fluid passage, and second piston means connected to said valve means and operatively arranged for selectively moving said valve means to one of said operating positions in response to a pressure differential acting on one end of said second piston means and for selectively moving said valve means to the other of said operating positions in response to a pressure differential acting on the other end of said second piston means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said first piston means and to said one end of said second piston means, and a second hydraulic conduit coupled to said other end of said first piston means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said first piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said second hydraulic conduit to said other end of said second piston means to receive hydraulic fluid therefrom only so long as the fluid pressure in said firsT hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cyle of said pump for selectively coupling said second hydraulic conduit to said pump outlet to supply hydraulic fluid at a second preselected pressure level to said other end of said second piston means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 35

The formation-testing apparatus of claim 30 further including: means coupling said fluid-admitting means to said first piston means for moving said fluid-admitting means into and out of engagement with a well bore wall upon extension and retraction of said first piston means.

Claim 36

The formation-testing apparatus of claim 30 wherein said fluid-admitting means include: a sealing member cooperatively arranged for sealing engagement with a well bore wall and having a central opening, and a tubular fluid-conducting member coupled to said fluid passage and disposed within said central opening.

Claim 37

The formation-testing apparatus of claim 32 wherein said second pressure-responsive means are cooperatively arranged on said tubular fluid-conducting member for controlling the flow of fluids between said tubular fluid-conducting member and said fluid passage.

Claim 38

The formation-testing apparatus of claim 33 further including: means coupling said fluid-admitting means to said first piston means for moving said fluid-admitting means into and out of engagement with a well bore wall upon extension and retraction of said first piston means.

Claim 39

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including first valve means coupled to said fluid passage and movable between an open position to admit well bore fluids into said fluid passage and a closed position to block the entrance of well bore fluids into said fluid passage, first piston-actuator means connected to said first valve means and operatively arranged for selectively moving said first valve means to its said closed position in response to a pressure differential acting on one end of said first piston-actuator means and for selectively moving said first valve means to its said open position in response to a pressure differential acting on the other end of said first piston-actuator means, second valve means connected in said fluid passage and movable between a closed position to block the flow of fluids through said fluid passage and an open position to allow fluids to flow through said fluid passage, and second piston-actuator means connected to said second valve means and operatively arranged for selectively moving said second valve means to its said open position in response to a pressure differential acting on one end of said second piston-actuator means and for selectively moving said second valve means to its said closed position in response to a pressure differential acting on the other end of said second piston-actuator means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said piston means, a second hydraulic conduit coupled to said other end of said piston means and to said other ends of said first and second piston-actuator means, and a third hydraulic conduit coupled to said one ends of said first and second piston-actuator means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said first hydraulic conduit to said third hydraulic conduit to supply hydraulic fluid to said ends of said first and second piston-actuator means only so long as the fluid pressure in said first hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cycle of said pump for selectively coupling said second hydraulic conduit to said pump outlet and coupling said third hydraulic conduit to said third hydraulic conduit to said pump inlet to supply hydraulic fluid at a second selected pressure level to said other ends of said first and second piston-actuator means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 40

Formation-testing apparatus adapted for suspension in a well bore traversing earth formations and comprising: a body having a fluid passage arranged thereon for receiving connate fluids; fluid-admitting means coupled to said fluid passage and cooperatively arranged on said body for engagement with a well bore wall to isolate a portion thereof from well bore fluids; first pressure-responsive means adapted for selectively engaging and disengaging said fluid-admitting means with and from a well bore wall and including piston means operatively arranged for extension toward a well bore wall in response to a pressure differential acting on one end of said piston means and for retraction from a well bore wall in response to a pressure differential acting on the other end of said piston means; second pressure-responsive means adapted for selectively controlling the flow of fluids in said fluid passage and including first valve means coupled to said fluid passage and movable between an open position to admit well bore fluids into said fluid passage and a closed position to block the entrance of well bore fluids into said fluid passage, first piston-actuator means connected to said first valve means and operatively arranged for selectively moving said first valve means to its said closed position in response to a pressure differential acting on one end of said first piston-actuator means and for selectively moving said first valve means to its said open position in response to a pressure differential acting on the other end of said first piston-actuator means, second valve means connected in said fluid passage and movable between a closed position to block the flow of fluids through said fluid passage and an open position to allow fluids to flow through said fluid passage, and second piston-actuator means connected to said second valve means and operatively arranged for selectively moving said second valve means to its said open position in response to a pressure differential acting on one end of said second piston-actuator means and for selectively moving said second valve means to its said closed position in response to a pressure differential acting on the other end of said second piston-actuator means; hydraulic actuating means on said body and including a pump selectively operable from the surface and adapted for supplying a hydraulic fluid at progressively-increasing pressures over a selected range of operating pressures, a first hydraulic conduit coupled to said one end of said piston means, a second hydraulic conduit coupled to said other end of said piston means and to said other ends of said first and second piston-actuator means, and a third hydraulic conduit coupled to said one ends of said first and second piston-actuator means; first control means operable upon a first operating cycle of said pump for selectively coupling said first hydraulic conduit to the outlet of said pump and coupling said second hydraulic conduit to the inlet of said pump to extend said piston means as said pump first supplies a hydraulic fluid at a first selected pressure level to said first hydraulic conduit; second control means operable only upon a further increase in fluid pressure in said first hydraulic conduit above said first selected pressure level for coupling said first hydraulic conduit to said third hydraulic conduit to supply hydraulic fluid to said ends of said first and second piston-actuator means only so long as the fluid pressure in said first hydraulic conduit is no less than said first selected pressure level; third control means operable upon a second operating cycle of said pump for selectively coupling said second hydraulic conduit to said pump outlet and coupling said third hydraulic conduit to said third hydraulic conduit to said pump inlet to supply hydraulic fluid at a second selected pressure level to said other ends of said first and second piston-actuator means; and fourth control means operable only upon a further increase in fluid pressure in said second hydraulic conduit above said second selected pressure level for coupling said first hydraulic conduit to said pump inlet only so long as the fluid pressure in said second hydraulic conduit is no less than said second selected pressure level.

Claim 41

The formation-testing apparatus of claim 35 wherein said piston means include a laterally-extendible piston member adapted for extension and retraction relative to one side of said body, and said fluid-admitting means are mounted on the other side of said body for engagement with one well bore wall upon extension of said extendible piston member against the opposite well bore wall.

Claim 42

The formation-testing apparatus of claim 35 wherein said piston means include a laterally-extendible piston member adapted for extension and retraction relative to one side of said body, and further including: means cooperatively coupling said fluid-admitting means to said piston member for moving said fluid-admitting means into and out of engagement with a well bore wall upon extension and retraction of said piston member.

Claim 43

The formation-testing apparatus of claim 35 wherein said piston means include first and second laterally-extendible piston members respectively adapted for simultaneous extension and retraction relative to opposite sides of said body, and further including: means cooperatively coupling said fluid-admitting means to said first piston member for moving said fluid-admitting means into and out of engagement with a well bore wall upon extension of said first and second piston members.

Claim 44

The formation-testing apparatus of claim 35 further including: sample-collecting means coupled to said fluid passage downstream of said second valve means.

Claim 45

The formation-testing apparatus of claim 39 further including: fifth control means selectively operable from the surface for controlling the admission of hydraulic fluid from said third hydraulic conduit to said one end of said second piston-actuator means.