Device for guiding sensor movement within a tube

Claim 2

A positional control mechanism for guiding mechanical movement within a tube, comprising: a. a mounting base defining a central guideway and structured for removable placement on an end of a tube; b. a drive gear having an opening therethrough in alignment with the central guideway and a drive element extending into the opening, the drive gear being rotatably coupled to the mounting base; c. an elongated carrier pipe extending through the openIng in the drive gear and mouting base central guideway and formed along one longitudinally extending portion with a drive slot for receiving the drive element and along a different longitudinally extending portion with a recessed gear rack; d. a working head carried by the carrier pipe; e. a first motor (28) connected to the mounting base and operatively coupled with the drive gear to cause rotation of the carrier pipe; f. a second motor (49) mounted on the drive gear and operatively coupled with the gear rack to selectively cause axial movement of the carrier pipe; g. actuator means for operating the first motor and second motor to cause movement of the carrier pipe and repositioning of the working head within the tube; and, h. bearing means located in the mounting base central guideway for receiving the carrier pipe in sliding, rotatable engagement.

Claim 3

The structure according to claim 1 wherein the mounting base includes: a cover plate structured to fit over one end of the tube, a pedestal spaced from the cover plate and arranged to mount the first motor and generally hold the first motor between the cover plate and itself, and the bearing means comprise two annular bushings (73 and 74) fixed within the central guideway in axially spaced locations.

Claim 4

The structure according to claim 2 wherein the mounting base includes: a sleeve which defines the central passageway and extends between the cover plate and pedestal, the sleeve being formed with an insert portion at one end for projection into the tube and a socketed cavity at the other end for seating the drive gear.

Claim 5

The structure according to claim 1 wherein: the first motor is a reversible electric motor with a power take-off shaft mounting a first pinion gear, and, the drive gear is a spur gear drivingly interengaged with the first pinion gear.

Claim 6

The structure according to claim 4 wherein: the drive element is a radially inwardly extending key, and, the drive slot is a key way that slidably receives the key and extends along the major portion of the length of the carrier pipe.

Claim 7

The structure according to claim 1 wherein: the second motor is a reversible electrical motor with a power take-off shaft mounting a second pinion gear drivingly interengaged with the gear rack.

Claim 8

The structure according to claim 1 wherein: the first motor is a first reversible electrical motor with a power take-off shaft mounting a first pinion gear, the drive gear is a spur gear drivingly interengaged with the first pinion gear, the drive element is a radially inwardly extending key, the drive slot is a key way that slidably receives the key and extends along the major portion of the length of the carrier pipe, and, the second motor is a second reversible electric motor with a power take-off shaft mounting a second pinion gear drivingly interengaged with the gear rack.

Claim 9

The structure according to claim 1 wherein: the working head is a sensor constructed to inspect the interior wall conditions of the tube.

Claim 10

The structure according to claim 8 including; a remote control unit equipped with means to transmit command signals through the actuator means to the first and second motors in accordance with a pre-determined program in order to periodically reposition the sensor.

Claim 11

The structure according to claim 9 wherein the remote control unit includes: an analog-to-digital converter connected to receive analog signals from the sensor and serving to convert the analog signals to digital signals.

Claim 12

The structure according to claim 10 wherein: the sensor is an ultra-sonic transducer.

Claim 13

A positional control mechanism for guiding mechanical movement within a tube for inspection of the interior wall volume of said tube comprising: a. a mounting base removably placed on an end of the tube, the mounting base having a sleeve that defines a central guideway; b. a spur gear having an opening therethrough in alignment with the central guideway and a drive element in the form of a key extending into the opening, the spur gear being rotatably coupled to the mounting base; c. an elongated carrier pipe coaxially aligned with and extending through the opening in the spur gear and mounting base sleeve and inserted in the tube, the carrier pipe being formed along one longitudinally extending portion with a drive slot in the form of a key way for receiving the drive element and along a different longitudinally extending portion with a recessed gear rack; d. a sensor carried by the carrier pipe; e. a first motor (28) connected to the mounting base and operatively coupled with the spur gear to cause rotation of the carrier pipe; f. a second motor (49) mounted on the spur gear and operatively coupled with the gear rack to selectively cause axial movement of the carrier pipe; and, g. actuator means for operating the first motor and the second motor to reposition the sensor within the tube and allow the sensor to scan the interior wall conditions of the tube.

Claim 14

A positional control mechanism for guiding mechanical movement within a tube for inspection of the interior wall volume of said tube comprising: a. a mounting base removably placed on an end of the tube, the mounting base having a sleeve that defines a central guideway; b. a spur gear having an opening therethrough in alignment with the central guideway and a drive element in the form of a key extending into the opening, the spur gear being rotatably coupled to the mounting base; c. an elongated carrier pipe coaxially aligned with and extending through the opening in the spur gear and mounting base sleeve and inserted in the tube, the carrier pipe being formed along one longitudinally extending portion with a drive slot in the form of a key way for receiving the drive element and along a different longitudinally extending portion with a recessed gear rack; d. a sensor carried by the carrier pipe; e. a first motor (28) connected to the mounting base and operatively coupled with the spur gear to cause rotation of the carrier pipe; f. a second motor (49) mounted on the spur gear and operatively coupled with the gear rack to selectively cause axial movement of the carrier pipe; and, g. actuator means for operating the first motor and the second motor to reposition the sensor within the tube and allow the sensor to scan the interior wall conditions of the tube.

Claim 15

The structure according to claim 12 wherein: the first motor is a reversible electric motor with a power take-off shaft mounting a first pinion gear interengaged with the spur gear, and, the second motor is a reversible electric motor with a power take-off shaft mounting a second pinion gear interengaged with the gear rack.

Claim 16

The structure according to claim 13 including: stop means including a limit switch for controlling rotation of the carrier pipe to guarantee 360*.

Claim 17

The structure according to claim 12 including: a remote control unit equipped with means to transmit command signals through the actuator means to the first and second motors in accordance with a predetermined program in order to periodically reposition the sensor.

Claim 18

The structure according to claim 15 including: encoder means for sensing rotational and axial movement of the carrier pipe and transmitting electrical signals to the remote control unit for evaluation, and, an analog-to-digital converter connected to receive analog signals from the sensor and serving to convert the analog signals to digital signals.

Claim 19

The structure according to claim 12 wherein: the sensor is an ultra-sonic transducer, the tube and mounting base are coupled in a fluid-tight relationship, a space formed between the tube and carrier pipe is filled with liquid immersing the transducer, and, a plug is removably inserted within the opposite end of the tube.

Claim 20

The structure according to claim 17 wherein: the tube is a control rod mechanism housing fixed in place within a nuclear reactor.