CONTROL SYSTEM AND INTERFACE FOR A TUNNELING APPARATUS

TECHNICAL FIELD

The present disclosure relates generally to trenchless drilling equipment. More particularly, the present disclosure relates to tunneling (e.g., drilling, backreaming, etc.) equipment capable of maintaining a precise grade and line.

BACKGROUND

Modern installation techniques provide for the underground installation of services required for community infrastructure. Sewage, water, electricity, gas and telecommunication services are increasingly being placed underground for improved safety and to create more visually pleasing surroundings that are not cluttered with visible services.

One method for installing underground services involves excavating an open trench. However, this process is time consuming and is not practical in areas supporting existing construction. Other methods for installing underground services involve boring a horizontal underground hole. However, most underground drilling operations are relatively inaccurate and unsuitable for applications on grade and on line.

PCT International Publication No. WO 2007/143773 discloses a micro-tunneling system and apparatus capable of boring and reaming an underground micro-tunnel at precise grade and line. While this system represents a significant advance over most prior art systems, further enhancements can be utilized to achieve even better performance.

SUMMARY

One aspect of the present disclosure relates to a tunneling (e.g., drilling, backreaming, etc.) apparatus having a drill head including a main body and a steering member that is moveable relative to the main body. The tunneling apparatus also includes a vacuum system for removing cuttings from the bore being drilled and a drilling fluid system for providing drilling fluid down the bore being drilled. The tunneling apparatus further includes control system that allows an operator to control rotation of a cutter of the drill head, the thrust applied to the drill head, and the amount of drilling fluid provided down the bore while concurrently steering the drill head and monitoring a vacuum pressure of the vacuum system. By monitoring the vacuum pressure, the operator can identify precursor plug conditions and immediately take corrective actions such as increasing the flow rate of drilling fluid, increasing the rotational speed of the cutting unit an/or decreasing or elimination thrust applied to the drill head. Steering can be accomplished through the use of a steering element (e.g., a joystick) of the control system and a screen showing the position of a guidance laser upon a target provided at the drill head. In certain embodiments, the various control components can be provided as part of a compact, portable control unit that can communicate with various other components of the control system by wired or wireless technology.

Another aspect of the present disclosure relates to a control system for a tunneling apparatus. The control system has a first mode of operation for drilling or pulling-back, and a second mode of operation for changing pipe sections (i.e., adding or removing pipe sections from a string of pipe sections).

A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depiction of a tunneling apparatus having features in accordance with the principles of the present disclosure;

FIG. 2 is a perspective view showing a male end of a pipe section suitable for use with the tunneling apparatus schematically depicted at FIG. 1;

FIG. 3 is a perspective view showing a female end of the pipe section of FIG. 2;

FIG. 4 is a perspective view of the pipe section of FIG. 2 with an outer shell removed to show internal components of the pipe section;

FIG. 5 is a perspective cross-sectional view of the pipe section of FIG. 2 with the pipe section being cut along a horizontal cross-sectional plane that bisects the pipe section;

FIG. 6 is a perspective cross-sectional view of the pipe section of FIG. 2 with the pipe section being cut along a vertical cross-sectional plane that bisects the pipe section;

FIG. 6A is a longitudinal cross-sectional view of an interface between two drive shafts of the pipe sections;

FIG. 7 is an end view showing the female end of the pipe section of FIG. 2;

FIG. 8 is an end view showing the male end of the pipe section of FIG. 2;

FIG. 9 is a cross-sectional view showing latches mounted at the female end of the pipe section of FIG. 2, the latches are shown in a non-latching orientation;

FIG. 10 is a cross-sectional view showing the latches of FIG. 9 in a latching orientation;

FIG. 11 is a cross-sectional view through a reinforcing plate of the pipe section of FIG. 2;

FIG. 12 shows an example drive unit suitable for use with the tunneling apparatus schematically depicted at FIG. 1;

FIG. 13 is another schematic depiction of the tunneling apparatus of FIG. 1;

FIG. 14 is a perspective view of an example control interface unit suitable for use with the tunneling apparatus of FIGS. 1-13;

FIG. 15 is a plan view of a control panel arrangement of the control interface unit of FIG. 14;

FIG. 16 is a perspective view of the control panel arrangement of FIG. 15;

FIG. 17 is a display of the control panel arrangement of FIGS. 15 and 16; and

FIG. 18 shows a screen displayed by a screen display apparatus incorporated into the display of FIG. 17.

DETAILED DESCRIPTION
A. Overview of Example Drilling Apparatus

FIG. 1 shows a tunneling apparatus 20 having features in accordance with the principles of the present disclosure. Generally, the apparatus 20 includes a plurality of pipe sections 22 that are coupled together in an end-to-end relationship to form a drill string 24. Each of the pipe sections 22 includes a drive shaft 26 rotatably mounted in an outer casing assembly 28. A drill head 30 is mounted at a distal end of the drill string 24 while a drive unit 32 is located at a proximal end of the drill string 24. The drive unit 32 includes a torque driver 32a adapted to apply torque to the drill string 24 and an axial driver 32b for applying thrust or pull-back force to the drill string 24. The torque driver 32a and the axial driver 32b can be powered by a hydraulic system (e.g., a system of pumps and hydrostatic drives) powered by a main system engine 33. Thrust or pull-back force from the drive unit 32 is transferred between the proximal end and the distal end of the drill string 24 by the outer casing assemblies 28 of the pipe sections 22. Torque is transferred from the proximal end of the drill string 24 to the distal end of the drill string 24 by the drive shafts 26 of the pipe sections 22 which rotate relative to the casing assemblies 28. The torque from the drive unit 32 is transferred through the apparatus 20 by the drive shafts 26 and ultimately is used to rotate a cutting unit 34 of the drill head 30.

The pipe sections 22 can also be referred to as drill rods, drill stems or drill members. The pipe sections are typically used to form an underground bore, and then are removed from the underground bore when product (e.g., piping) is installed in the bore.

The drill head 30 of the drilling apparatus 20 can include a drive stem 46 rotatably mounted within a main body 38 of the drill head 30. The main body 38 can include a one piece body, or can include multiple pieces or modules coupled together. A distal end of the drive stem 46 is configured to transfer torque to the cutting unit 34. A proximal end of the drive stem 46 couples to the drive shaft 26 of the distal-most pipe section 22 such that torque is transferred from the drive shafts 26 to the drive stem 46. In this way, the drive stem 46 functions as the last leg for transferring torque from the drive unit 32 to the cutting unit 34. The outer casing assemblies 28 transfer thrust and/or pull back force to the main body 38 of the drill head. The drill head 30 preferably includes bearings (e.g., axial/thrust bearings and radial bearings) that allow the drive stem 46 to rotate relative to the main body 38 and also allow thrust or pull-back force to be transferred from the main body 38 through the drive stem 46 to the cutting unit 34.

In certain embodiments, the tunneling apparatus 20 is used to form underground bores at precise grades. For example, the tunneling apparatus 20 can be used in the installation of underground pipe installed at a precise grade. In some embodiments, the tunneling apparatus 20 can be used to install underground pipe or other product having an outer diameter less than 600 mm or less than 300 mm.

It is preferred for the tunneling apparatus 20 to include a steering arrangement adapted for maintaining the bore being drilled by the tunneling apparatus 20 at a precise grade and line. For example, referring to FIG. 1, the drill head 30 includes a steering shell 36 mounted over the main body 38 of the drill head 30. Steering of the tunneling apparatus 20 is accomplished by generating radial movement between the steering shell 36 and the main body 38 (e.g., with radially oriented pistons, one or more bladders, mechanical linkages, screw drives, etc.). Radial steering forces for steering the drill head 30 are transferred between the shell 36 and the main body 38. From the main body 38, the radial steering forces are transferred through the drive stem 46 to the cutting unit 34.

Steering of the tunneling apparatus 20 is preferably conducted in combination with a guidance system used to ensure the drill string 24 proceeds along a precise grade and line. For example, as shown at FIG. 1, the guidance system includes a laser 40 that directs a laser beam 42 through a continuous axially extending air passage (e.g., passage 43 shown at FIG. 13) defined by the outer casing assemblies 28 of the pipe sections 22 to a target 44 located adjacent the drill head 30. The air passage extends from the proximal end to the distal end of the drill string 24 and allows air to be provided to the cutting unit 34.

The tunneling apparatus 20 also includes an electronic controller 50 (e.g., a computer or other processing device) linked to a user interface 52 and a monitor 54. The user interface 52 can include a keyboard, joystick, mouse or other interface device. The controller 50 can also interface with a camera 60 such as a video camera that is used as part of the steering system. For example, the camera 60 can generate images of the location where the laser hits the target 44. It will be appreciated that the camera 60 can be mounted within the drill head 30 or can be mounted outside the tunneling apparatus 20 (e.g., adjacent the laser). If the camera 60 is mounted at the drill head 30, data cable can be run from the camera through a passage that runs from the distal end to the proximal end of the drill string 24 and is defined by the outer casing assemblies 28 of the pipe sections 22. In still other embodiments, the tunneling apparatus 20 may include wireless technology that allows the controller to remotely communicate with the down-hole camera 60.

During steering of the tunneling apparatus 20, the operator can view the camera-generated image showing the location of the laser beam 42 on the target 44 via the monitor 54. Based on where the laser beam 42 hits the target 44, the operator can determine which direction to steer the apparatus to maintain a desired line and grade established by the laser beam 42. The operator steers the drill string 24 by using the user interface to cause a shell driver 39 to modify the relative radial position of the steering shell 36 and the main body 38 of the drill head 30. In one embodiment, a radial steering force/load is applied to the steering shell 36 in the radial direction opposite to the radial direction in which it is desired to turn the drill string. For example, if it is desired to steer the drill string 24 upwardly, a downward force can be applied to the steering shell 36 which forces the main body 38 and the cutting unit 34 upwardly causing the drill string to turn upwardly as the drill string 24 is thrust axially in a forward/distal direction. Similarly, if it is desired to steer downwardly, an upward force can be applied to the steering shell 36 which forces the main body 38 and the cutting unit 34 downwardly causing the drill string 24 to be steered downwardly as the drill string 24 is thrust axially in a forward/distal direction.

In certain embodiments, the radial steering forces can be applied to the steering shell 36 by a plurality of radial pistons that are selectively radially extended and radially retracted relative to a center longitudinal axis of the drill string through operation of a hydraulic pump and/or valving (e.g., see pump 700 at FIGS. 25-28). The hydraulic pump and/or valving are controlled by the controller 50 based on input from the user interface. In one embodiment, the hydraulic pump and/or the valving are located outside the hole being bored and hydraulic fluid lines are routed from pump/valving to the radial pistons via a passage that runs from the distal end to the proximal end of the drill string 24 and is defined within the outer casing assemblies 28 of the pipe sections 22. In other embodiments, the hydraulic pump and/or valving can be located within the drill head 30 and control lines can be routed from the controller 50 to the hydraulic pump and/or valving through a passage that runs from the distal end to the proximal end of the drill string 24 and is defined within the outer casing assemblies 28 of the pipe sections 22. In still other embodiments, the tunneling apparatus 20 may include wireless technology that allows the controller to remotely control the hydraulic pump and/or valving within the drill head 30.

To assist in drilling, the tunneling apparatus 20 can also include a fluid pump 63 for forcing drilling fluid from the proximal end to the distal end of the drill string 24. In certain embodiments, the drilling fluid can be pumped through a central passage (e.g., passage 45 shown at FIG. 13) defined through the drive shafts 26. The central passage defined through the drive shafts 26 can be in fluid communication with a plurality of fluid delivery ports provided at the cutting unit 34 such that the drilling fluid is readily provided at a cutting face of the cutting unit 34. Fluid can be provided to the central passage though a fluid swivel located at the drive unit 32. The fluid pump 63 can be driven by the hydraulic system powered by the main system engine 33. A valve 400 controlled by the controller 50 can be used to selectively open and close fluid communication between the fluid pump 63 and the fluid passage (e.g., passage 45) of the drill string.

The tunneling apparatus 20 can also include a vacuum system for removing spoils and drilling fluid from the bore being drilled. For example, the drill string 24 can include a vacuum passage (e.g., passage 47 shown at FIG. 13) that extends continuously from the proximal end to the distal end of the drill string 24. The proximal end of the vacuum passage can be in fluid communication with a vacuum 65 (e.g., a vacuum pump) and the distal end of the vacuum passage is typically directly behind the cutting unit 34 adjacent the bottom of the bore. The vacuum 65 applies vacuum pressure (i.e., negative pressure/pressure below atmospheric pressure) to the vacuum passage to remove spoils and liquid (e.g., drilling fluid from fluid passage 45) from the bore being drilled. A vacuum break valve 402 controlled by the controller 50 can be used to selectively open and close (i.e., connect and break) fluid communication between the vacuum 65 and the vacuum passage of the drill string (e.g., passage 47). The vacuum 65 can be powered by vacuum engine 404. For example, the vacuum engine 404 can power a hydraulic drive system that drives the vacuum 65. At least some air provided to the distal end of the drill string 24 through the air passage 43 is also typically drawn into the vacuum passage to assist in preventing plugging of the vacuum passage. In certain embodiments, the liquid and spoils removed from the bore though the vacuum passage can be delivered to a storage tank 67.

B. Example Pipe Section

FIGS. 2-11 show an example of one of the pipe sections 22 in accordance with the principles of the present disclosure. The pipe section 22 is elongated along a central axis 120 and includes a male end 122 (see FIG. 2) positioned opposite from a female end 124 (see FIG. 3). When a plurality of the pipe sections 22 are strung together, the female ends 124 are coupled to the male ends 122 of adjacent pipe sections 22.

Referring to FIGS. 2 and 3, the outer casing assembly 28 of the depicted pipe section 22 includes end plates 126 positioned at the male and female ends 122, 124. The outer casing assembly 28 also includes an outer shell 128 that extends from the male end 122 to the female end 124. The outer shell 128 is generally cylindrical and defines an outer diameter of the pipe section 22. In a preferred embodiment, the outer shell 128 is configured to provide support to a bore being drilled to prevent the bore from collapsing during the drilling process.

As shown at FIG. 3, the outer casing assembly 28 also defines an open-sided passage section 130 having a length that extends from the male end 122 to the female end 124 of the pipe section 22. The open-sided passage section 130 is defined by a channel structure 132 (see FIG. 11) having outer portions 134 secured (e.g., welded) to the outer shell 128. The channel structure 132 defines an open side 136 positioned at the outer shell 128. The open side 136 faces generally radially outwardly from the outer shell 128 and extends along the entire length of the pipe section 22. When the pipe sections 22 are coupled together to form the drill string 24, the open-sided passage sections 130 co-axially align with one another and cooperate to define a continuous open-sided exterior channel that extends along the length of the drill string 24.

The outer casing assembly 28 of the pipe section 22 also includes structure for rotatably supporting the drive shaft 26 of the pipe section 22. For example, as shown at FIGS. 4-6, the outer casing assembly 28 includes a tubular shaft receiver 140 that extends along the central axis 120 from the male end 122 to the female end 124. Opposite ends of the shaft receiver 140 are secured (e.g., welded) to the end plates 126. The shaft receiver 140 includes a central portion 142 and end collars 144. The end collars 144 are secured (e.g., welded) to ends of the central portion 142. The end collars 144 are of larger diameter than the central portion 142. The end collars 144 are also secured (e.g., welded) to the end plates 126 such that the collars 144 function to fix the central portion 142 relative to the end plates 126.

Referring still to FIGS. 4-6, the drive shaft 26 is rotatably mounted within the shaft receiver 140 of the outer casing assembly 28. A bearing 143 (e.g., a radial bushing type bearing as shown at FIG. 6) is preferably provided in at least one of the collars 144 to rotatably support the drive shaft 26 within the shaft receiver 140. In certain embodiments, bearings for supporting the drive shaft 26 can be provided in both of the collars 144 of the shaft receiver 140.

The outer casing assembly 28 also includes a plurality of gusset plates 160 secured between the outer shell 128 and the central portion 142 of the shaft receiver 140 (see FIGS. 4, 5 and 11). The gusset plates 160 assist in reinforcing the outer shell 128 to prevent the outer shell from crushing during handling or other use.

The pipe section 22 also includes a plurality of internal passage sections that extend axially through the pipe section 22 from the male end 122 to the female end 124. For example, referring to FIG. 6, the outer casing assembly 28 defines a first internal passage section 170 and a separate second internal passage section 172. The first and second internal passage sections 170, 172 each extend completely through the length of the pipe section 22. The first internal passage section 170 is defined by a tube structure 173 that extends along the length of the pipe section 22 and has opposite ends secured to the end plates 126. The end plates 126 define openings 175 that align with the tube structure 173. A face seal 177 or other sealing member can be provided at an outer face of at least one of the end plates 126 surrounding the openings 175 such that when two of the pipe sections 22 are coupled together, their corresponding passage sections 170 co-axially align and are sealed at the interface between the male and female ends 122, 124 of the connected pipe sections 22. When the pipe sections 22 are coupled together to form the drill string 24, the first internal passage sections 170 are co-axially aligned with each other and cooperate to form the continuous vacuum passage 47 that extends axially through the length of the drill string 24.

Referring again to FIG. 6, the second internal passage section 172 is defined by a tube structure 180 having opposite ends secured to the end plates 126. The end plates 126 have openings 181 that align with the tube section 180. A face seal 179 or other sealing member can be provided at an outer face of at least one of the end plates 126 surrounding the openings 181 such that when two of the pipe sections 22 are coupled together, their corresponding passage sections 172 co-axially align and are sealed at the interface between the male and female ends 122, 124 of the connected pipe sections 22. When the pipe sections 22 are coupled together to form the drill string 24, the second internal passage sections 172 are co-axially aligned with each other and cooperate to form the continuous air passage 43 that extends axially through the length of the drill string 24.

Referring still to FIG. 6, the drive shaft 26 extends through the shaft receiver 140 and includes a male torque transferring feature 190 positioned at the male end 122 of the pipe section 22 and a female torque transferring feature 192 positioned at the female end 124 of the pipe section 22. The male torque transferring feature 190 is formed by a stub (e.g., a driver) that projects outwardly from the end plate 126 at the male end 122 of the pipe section 22. The male torque transferring feature 190 has a plurality of flats (e.g., a hexagonal pattern of flats forming a hex-head) for facilitating transmitting torque from drive shaft to drive shaft when the pipe sections 22 are coupled in the drill string 24. The female torque transferring feature 192 of the drive shaft 26 defines a receptacle (e.g., a socket) sized to receive the male torque transferring feature 190 of the drive shaft 26 of an adjacent pipe section 22 within the drill string 24. The female torque transferring feature 192 is depicted as being inset relative to the outer face of the end plate 126 at the female end 124 of the pipe section 22. In one embodiment, the female torque transferring feature 192 has a shape that complements the outer shape of the male torque transferring feature 190. For example, in one embodiment, the female torque transferring feature 192 can take the form of a hex socket. The interface between the male and female torque transferring features 190, 192 allows torque to be transferred from drive shaft to drive shaft within the drill string 24 defined by interconnected the pipe sections 22.

As shown at FIG. 6, each of the drive shafts 26 defines a central passage section 194 that extends longitudinally through the drive shaft 26 from the male end 122 to the female end 124. When the pipe sections 22 are interconnected to form the drill string 24, the central passage sections 194 of the drive shafts 26 are axially aligned and in fluid communication with one another such that a continuous, interrupted central passage (e.g., central passage 45 shown at FIG. 13) extends through the drive shafts 26 of the drill string 24 from the proximal end to the distal end of the drill string 24. The continuous central passage 45 defined within the drive shafts 26 allows drilling fluid to be pumped through the drill string 24 to the cutting unit 34.

FIG. 6A shows an example coupling between the male and female torque transferring features 190, 192. The female torque transferring feature 192 is shown as a collar 1010 having a first end 1012 positioned opposite from a second end 1014. A bore 1015 passes through the collar 1010 from the first end 1012 to the second end 1014. The bore 1015 has a first region 1016 defining torque transferring features (e.g., internal flats in a pattern such as a hexagonal pattern, internal splines, etc.) and a second region 1018 having an enlarged cross-dimension as compared to the first region 1016. The first region 1016 extends from the first end 1012 of the collar 1010 to a radial shoulder 1020. The second region 1018 extends from the second end 1014 of the collar 1010 to the radial shoulder 1020. The first end 1012 of the collar 1010 is fixedly secured (e.g., welded) to a corresponding drive shaft 26a having a shortened torque transmitting section 1022 that fits within the first region 1016 of the bore 1015. The torque transmitting section 1022 has torque transmitting features (e.g., external flats, splines, etc.) that engage the first region 1016 such that torque can be transferred between the shaft 26a and the collar 1010. In one embodiment, the torque transmitting section 1022 has a length less that one-third a corresponding length of the first region 1016 of the collar 1010. The portion of the first region 1016 that is not occupied by the shortened torque transmitting section 1022 is configured to receive the male torque transferring feature 190 of an adjacent drive shaft 26b such that torque can be transferred between the drive shafts 26a, 26b. The second region 1018 of the bore 1015 can be defined by an inner cylindrical surface of the collar 1010 that assists in guiding the male torque transferring feature 190 into the first region 1016 when the drive shafts 26a, 26b are moved axially into connection with one another. Additionally, a sealing member 1024 (e.g., a radial seal such as an o-ring seal) can be mounted within the second region 1018. The sealing member 1024 can provide a seal between the male torque transferring feature 190 and the second region 1018 of the bore 1015 for preventing drilling fluid from escaping from the central passage 45 at the joint between the drive shafts 26a, 26b.

The male and female ends 122, 124 of the pipe sections 22 are configured to provide rotational alignment between the pipe sections 22 of the drill string 24. For example, as shown at FIG. 2, the male end 122 includes two alignment projections 196 (e.g., pins) positioned at opposite sides of the central longitudinal axis 120. Referring to FIG. 5, each of the alignment projections 196 includes a base section 197 anchored to the end plate 126 at the male end 122. Each of the alignment projections 196 also includes a main body 195 that projects axially outwardly from the base section 197. The main body 195 includes a head portion 198 with a tapered outer end and a necked-down portion 199 positioned axially between head portion 198 and the base section 197. When a male end 122 of a first pipe section 22 is brought into engagement with the female end 124 of a second pipe section 22, the main bodies 195 of the alignment projections 196 provided at the male end 122 fit within (e.g., slide axially into) corresponding projection receptacles 200 (shown at FIG. 3) provided at the female end 124. As the main bodies 195 of the alignment projections 196 slide axially within the projection receptacles 200, slide latches 202 positioned at the female end 124 (see FIG. 9) are retained in non-latching positions in which the latches 202 do not interfere with the insertion of the projections 196 through the receptacles 200. The slide latches 202 include openings 206 corresponding to the projection receptacles 200 at the female end 124. The openings 206 include first regions 208 each having a diameter D1 (see FIG. 9) larger than an outer diameter D2 (see FIG. 8) of the head portions 198 and second portions 210 each having a diameter D3 (see FIG. 9) that generally matches an outer diameter defined by the necked-down portion 199 of the alignment projections 196. The diameter D3 is smaller than the outer diameter D2 defined by the head portion 198. The projection receptacles 200 have a diameter D4 (see FIG. 7) that is only slightly larger than the diameter D2. When the slide latches 202 are in the non-latching position, the first regions 208 of the openings 206 co-axially align with the projection receptacles 200. After the main bodies of the alignment projections 196 are fully inserted within the projection receptacles 200, a separate connection step is performed in which the latches 202 are moved (e.g., manually with a hammer) to latching positions in which the alignment projections 196 are retained within the projection receptacles 200.

The slide latches 202 are slideable along slide axes 212 relative to the outer casing 28 of the pipe section 22 between the latching positions (see FIG. 10) and the non-latching positions (see FIG. 9). In non-latching positions, the first regions 208 of the openings 206 of the slide latches 202 coaxially align with the projection receptacles 200. In the latching positions, the first regions 208 of the openings 206 are partially offset from the projections receptacles 200 and the second regions 210 of the openings 206 at least partially overlap the projection receptacles 200.

To couple two pipe sections together, the alignment projections 196 of one of the pipe sections can be inserted into the projection receptacles 200 of the other pipe section. With the slide latches 202 retained in the non-latching positions (i.e., a projection clearance position), the main bodies 195 of the alignment projections 196 can be inserted axially into the projection receptacles 200 and through the first regions 208 of the openings 206 without interference from the slide latches 202. After the alignment projections 196 have been fully inserted into the projection receptacles 200 and relative axial movement between the pipe sections has stopped, the slide latches 202 can be moved to the latching positions to make a connection between the pipe sections 22. When in the latching positions, the second regions 210 of the openings 206 fit over the necked-down portions 199 of the alignment projections 196 such that portions of the slide latches 202 overlap the head portions 198 of the projections 196. This overlap/interference between the slide latches 202 and the head portions 198 of the alignment projections 196 prevents the main bodies 195 of the alignment projections 196 from being axially withdrawn from the projection receptacles 200. In this way, a secure mechanical coupling is provided between adjacent individual pipe sections 22. No connection is made between the pipe sections 22 until the slide latches 202 have been moved to the latched position. To disconnect the pipe sections 22, the slide latches 202 can be returned to the non-latching position thereby allowing the alignment projections 196 to be readily axially withdrawn from the projection receptacles 200 and allowing the pipe sections 22 to be axially separated from one another.

The slide axis 212 of each slide latch 202 extends longitudinally through a length of its corresponding slide latch 202. Each slide latch 202 also includes a pair of elongate slots 220 having lengths that extend along the slide axis 212. The outer casing assembly 28 of the pipe section 22 includes pins 222 that extend through the slots 220 of the slide latches 202. The pins 222 prevent the slide latches 202 from disengaging from the outer casing assemblies 28. The slots 220 also provide a range of motion along the slide axes 212 through which the slide latches 202 can slide between the non-latching position and the latching position.

When two of the pipe sections are latched, interference between the slide latches 202 and the enlarged heads/ends 198 of the projections 196 mechanically interlocks or couples the adjacent pipe sections 22 together such that pull-back load or other tensile loads can be transferred from pipe section 22 to pipe section 22 in the drill string 24. This allows the drill string 24 to be withdrawn from a bored hole by pulling the drill string 24 back in a proximal direction. The pull-back load is carried by/through the casing assemblies 28 of the pipe sections 22 and not through the drive shafts 26. Prior to pulling back on the drill string 24, the drill head 30 can be replaced with a back reamer adapted to enlarge the bored hole as the drill string 24 is pulled back out of the bored hole.

The alignment projections 196 and receptacles 200 also maintain co-axial alignment between the pipe sections 22 and ensure that the internal and external axial passage sections defined by each of the pipe sections 24 co-axially align with one another so as to define continuous passageways that extend through the length of the drill string 24. For example, referring to FIG. 9, the alignment provided by the projections 196 and the receptacles 200 ensures that the first internal passage sections 170 of the pipe sections 22 are all co-axially aligned with one another (e.g., all positioned at about the 6 o'clock position relative to the central axis 120), the second internal passages 172 are all co-axially aligned with one another (e.g., all positioned generally at the 12 o'clock position relative to the central axial 120), and the open sided channels 130 are all co-axially aligned with one another (e.g., all positioned generally at the 1 o'clock position relative to the central axis 120).

C. Example Drive Unit

FIG. 12 shows an example configuration for the drive unit 32 of the tunneling/drilling apparatus 20. Generally, the drive unit 32 includes a carriage 300 that slidably mounts on a track structure 302. The track structure 302 is supported by a base of the drive unit 32 adapted to be mounted within an excavated structure such as a pit. Extendable feet 305 can be used to anchor the tracks within the pit and extendable feet 306 can be used to set the base at a desired angle relative to horizontal. The drive unit 32 includes a thrust driver for moving the carriage 300 proximally and distally along an axis 303 parallel to the track structure 302. The thrust driver can include a hydraulically powered pinion gear arrangement (e.g., one or more pinion gears driven by one or more hydraulic motors) carried by the carriage 300 that engages an elongated gear rack 307 that extends along the track structure 302. In other embodiments, hydraulic cylinders or other structures suitable for moving the carriage distally and proximally along the track can be used. The drive unit 32 also includes a torque driver (e.g., a hydraulic drive) carried by the carriage 300 for applying torque to the drill string 24. For example, as shown at FIG. 12, the drive unit can include a female rotational drive element 309 mounted on the carriage 300 that is selectively driven/rotated in clockwise and counter clockwise directions about the axis 303 by a drive (e.g., hydraulic drive motor) carried by the carriage 300. The female rotational drive element 309 can be adapted to receive the male torque transferring feature 190 of the drive shaft 26 corresponding to the proximal-most pipe section of the drill string 24. Projection receptacles 311 are positioned on opposite sides of the female drive element 309. The projection receptacles 311 are configured to receive the projections 196 of the proximal-most pipe section 22 to ensure that the proximal-most pipe section 22 is oriented at the proper rotational/angular orientation about the central axis 303 of the drill string.

The carriage also carries a vacuum hose port 313 adapted for connection to a vacuum hose that is in fluid communication with the vacuum 65 of the tunneling apparatus 20. The vacuum hose port 313 is also in fluid communication with a vacuum port 314 positioned directly beneath the female drive element 309. The vacuum port 314 co-axially aligns with the first internal passage section 170 of the proximal-most pipe section 22 when the proximal-most pipe section is coupled to the drive unit 32. In this way, the vacuum 65 is placed in fluid communication with the vacuum passage 47 of the drill string 24 so that vacuum can be applied to the vacuum passage 47 to draw slurry through the vacuum passage 47.

The carriage 300 also defines a laser opening 315 through which the laser beam 42 from the laser 40 can be directed. The laser beam opening 315 co-axially aligns with the second internal passage section 172 of the proximal-most pipe section 22 when the proximal-most pipe section 22 is coupled to the drive unit 32. In this way, the laser beam 42 can be sent through the air passage 43 of the drill string 24.

The female rotational drive element 309 also defines a central opening in fluid communication with a source of drilling fluid (e.g., the fluid/liquid pump 63 of the tunneling apparatus 20). When the female rotational drive element 309 is connected to the male torque transferring feature 190 of the drive shaft 26 of the proximal-most pipe section, drilling fluid can be introduced from the source of drilling fluid through the male torque transferring feature 190 to the central fluid passage (e.g., passage 45) defined by the drive shafts 26 of the pipe sections 22 of the drill string 24. The central fluid passage defined by the drive shafts 26 carries the drilling fluid from the proximal end to the distal end of the drill string 24 such that drilling fluid is provided at the cutting face of the cutting unit 34.

To drill a bore, a pipe section 22 with the drill head 30 mounted thereon is loaded onto the drive unit 32 while the carriage is at a proximal-most position of the track structure 302. The proximal end of the pipe section 22 is then coupled to the carriage 300. Next, the thrust driver propels the carriage 300 in a distal direction along the axis 303 while torque is simultaneously applied to the drive shaft 26 of the pipe section 22 by the female rotational drive element 309. By using the thrust driver to drive the carriage 300 in the distal direction along the axis 303, thrust is transferred from the carriage 300 to the outer casings 28 of the pipe section 22 thereby causing the pipe section 22 to be pushed distally into the ground. Once the carriage 300 reaches the distal-most position of the track structure 302, the proximal end of the pipe section 22 is disconnected from the carriage 300 and the carriage 300 is returned back to the proximal-most position. The next pipe section 22 is then loaded into the drive unit 32 by connecting the distal end of the new pipe section 22 to the proximal end of the pipe section 22 already in the ground and also connecting the proximal end of the new pipe section 22 to the carriage 300. The carriage 300 is then propelled again in the distal direction while torque is simultaneously applied to the drive shaft 26 of the new pipe section 22 until the carriage 300 reaches the distal-most position. Thereafter, the process is repeated until the desired number of pipe sections 22 have been added to the drill string 24.

The drive unit 32 can also be used to withdraw the drill string 24 from the ground. By latching the projections 196 of the proximal-most pipe section 22 within the projection receptacles 311 of the drive unit carriage 300 (e.g., with slide latches provided on the carriage) while the carriage 300 is in the distal-most position, and then using the thrust driver of the drive unit 32 to move the carriage 300 in the proximal direction from the distal-most position to the proximal-most position, a pull-back load is applied to the drill string 24 which causes the drill string 24 to be withdrawn from the drilled bore in the ground. If it is desired to back ream the bore during the withdrawal of the drill string 24, the cutting unit 34 can be replaced with a back reamer that is rotationally driven by the torque driver of the drive unit 32 as the drill string 24 is pulled back. After the proximal-most pipe section 22 has been withdrawn from the bore and disconnected from the drive unit 32, the carriage 300 can be moved from the proximal-most position to the distal-most position and connected to the proximal-most pipe section still remaining in the ground. Thereafter, the retraction process can be repeated until all of the pipe sections have been pulled from the ground.

D. Example Vacuum Passage Plug Detection System

FIG. 13 is another schematic view of the tunneling apparatus 20 of FIG. 1. Referring to FIG. 13, the air and vacuum passages 43, 47 that extend axially through the drill string 24 are schematically depicted. The drive shafts 26 that extend axially through the drill string from the drive unit 32 to the cutting unit 34 are also schematically depicted. The fluid/liquid pump 63 is shown directing drilling fluid through the central fluid passageway 45 that is defined by the drive shafts 26 and that extends from the proximal end to the distal end of the drill string 24. In other embodiments, the fluid/liquid pump 63 can convey the drilling fluid down a fluid line positioned within the channel defined by the open-sided passage sections 130 of the pipe sections 22. The air passage 43 is shown in fluid communication with an air pressure source 360 that directs compressed air into the proximal end of the air passage 43. The air pressure source 360 can include a fan, blower, air compressor, air pressure accumulator or other source of compressed air. The vacuum passage 47 is shown in fluid communication with the vacuum 65 for removing spoils from the bore. The vacuum 65 applies vacuum to the proximal end of the vacuum passage 47.

As a bore is formed by the tunneling apparatus 20, it is possible for the vacuum passage 47 to become plugged adjacent the distal end of the drill string 24. Once the vacuum passage 47 becomes plugged, the vacuum passage 47 can be difficult to clear. For example, it may be necessary to withdraw the drill string 24 from the bore and manually clear the obstruction. Thus, the tunneling apparatus 20 is equipped with features that reduce the likelihood of the vacuum passage 47 becoming plugged. For example, by applying positive air pressure to the proximal end of the air passage 43 via the source of air pressure 360, more air is provided to the distal end of the drill string 24 thereby reducing the likelihood of plugging. The air is forced to flow (i.e., blown by the source of air pressure 360) down the air passage 43 to adjacent the cutting unit 34 and then flows into the vacuum passage 47. In this way, positive pressure from the source or air pressure 360 helps push debris/spoils proximally into and through the vacuum passage 47 and the source of vacuum 65 pulls debris/spoils proximally into and through the vacuum passage 47. In certain embodiments, the flow rate and pressure of the air blown down the air passage 43 are coordinated and balanced with the evacuation rate provided by the source of vacuum 65.

One or more pressure sensing locations 370a, 370b can be provided at locations along the vacuum path from the distal end of the drill string to the vacuum 65. The pressure sensing location 370a is provided down-hole at the vacuum passage 47 near the distal end of the drill string. For example, the pressure sensing location 370a can be within the drill head. The pressure sensing location 370b is located above-ground adjacent to an intake for the vacuum 65. For example, the pressure sensing location 370b can be at a transition between the pipe sections and the intake to the vacuum 65. The vacuum 65 and the storage tank 67 can be positioned at a higher elevation than the drill string (e.g., above ground) with the transition conduit extending upwardly (e.g., vertically) from adjacent the drill string/drive unit 32 to the vacuum 65. Another pressure sensing location can be provided at or within the vacuum 65 itself. This sensing location can provide an indication regarding whether the vacuum 65 is operating properly. The pressure sensing locations are locations along the vacuum path where pressure sensors 372 are placed in fluid communication with the vacuum path. In this way, the pressure sensors can be used to take vacuum pressure readings representative of the real-time vacuum pressure at the pressure sensing locations 370a, 370b. By sensing pressure at multiple locations, it is possible to better diagnose where a blockage may be occurring and to better assess the overall effectiveness of the system.

The pressure sensors 372 preferably interface with the controller 50 and provide vacuum pressure data used by the controller 50 to monitor the status of the vacuum system. A variation in vacuum pressure compared to the vacuum pressure associated with normal (i.e., unplugged) operation of the vacuum system can be a precursor plugging characteristic used by the controller 50 as an indicator that the vacuum path is becoming plugged. Therefore, if the controller 50, via the pressure data provided by the pressure sensors 372, detects a variation in vacuum pressure that reaches a predetermined alert level, the controller 50 may take action suitable for reducing the likelihood that the vacuum passage 47 becomes fully blocked. For example, the controller 50 may reduce the amount of thrust that is being applied to the drill string 24 or may modify the rotational speed of the cutting unit 34 (e.g., the rotational speed of the cutting unit may be increased, decreased, stopped or reversed). The controller 50 may also completely stop thrusting of the drill string or may even retract the drill string until the pressure sensor 372 indicates that the vacuum pressure within the vacuum channel has returned to an acceptable level. In certain embodiments, the controller may cause the vacuum to stop applying vacuum pressure to the passage 47, and positive pressure can be applied to the passage 47 to blow the possible obstruction distally out of the passage 43 back to the cutting unit where the possible obstruction can be further reduced in size. Alternatively, vacuum may be applied to the air channel 43 to draw debris toward the air channel 43 while positive pressure is applied to the passage 47 to blow debris from the passage 47. In other embodiments, the controller 50 may issue an alert or alarm to the operator (e.g., via monitor 54, an alarm light or audible signal) indicating that a vacuum plug event has been detected. The controller 50 may also provide operational instructions/recommendations for preventing the vacuum passage from being plugged (e.g., stop thrust, reverse thrust, etc.). In still other embodiments, the controller may cause the amount of drilling fluid being provided down the hole to increase when a plug condition is detected. In one example embodiments, the controller automatically decreases thrust, increases the rotational speed of the cutting unit and increase the amount of drilling fluid provided down the hole when a precursor plugging characteristic is detected. Any combination of the above actions may be automatically implemented by the controller 50 or manually implemented by the operator.

In still other embodiments, the controller 50 may interface with a vacuum pressure read-out (e.g., a digital or mechanical display/gauge) that displays the vacuum pressure sensed by the pressure sensor 372. Therefore, by monitoring the vacuum pressure read-out, the operator can note variations in vacuum pressure and modify operation of the tunneling apparatus accordingly to reduce the likelihood of plugging. For example, the operator can implement one or more of the remedial actions described above.

In one example, a precursor plugging characteristic is detected by the controller 50 when the vacuum pressure increases (i.e., moves or spikes in magnitude in a direction extending away from atmospheric pressure and toward complete vacuum) to a predetermined alert level greater in magnitude than the vacuum pressure associated with normal unplugged operating conditions. This would typically occur when a plug begins to form at a location down-hole from a given pressure sensing location (i.e., the pressure sensing location is between the source of vacuum and the plugging location). In another example, a precursor plugging characteristic is detected by the controller 50 when the vacuum pressure decreases (i.e., moves or spikes in magnitude in a direction extending away toward atmospheric pressure and away from complete vacuum) to a predetermined alert level less in magnitude than the vacuum pressure associated with normal unplugged operating conditions. This would typically occur when a plug begins to form at a location between the source of vacuum and the pressure sensing location. When a precursor plugging characteristic is detected, the controller can alert the operator of the precursor plugging condition (e.g., with an audible or visual signal) and/or can automatically modify operation of the tunneling apparatus to prevent full blockage of the vacuum channel.

Air flow in the air channel 43 can also function as an indicator (i.e., a precursor plugging characteristic) regarding whether the vacuum path is in the process of becoming blocked. For example, a reduction in air flow within the air channel 43 compared to the amount of air flow through the air channel 43 during normal operation of the vacuum system in an unplugged state can provide an indication that the vacuum path is in the process of becoming blocked. To monitor air flow within the air passage 43, the controller 50 can interface with an air flow sensor 374 that senses the amount of air flow within the air channel 43. If the controller 50 detects that the air flow within the air passage 43 has fallen below a predetermined alert level, the controller 50 can modify operation of the tunneling apparatus to prevent full blockage of the vacuum channel as described above. Further, as indicated above, the controller may issue an alert to the operator and provide recommended remedial actions.

In still other embodiments, the controller 50 may interface with an air-flow read-out (e.g., a digital or mechanical display/gauge) that displays the air flow rate sensed by the sensor 374. Therefore, by monitoring the air flow read-out, the operator can note variations in air flow and modify operation of the tunneling apparatus accordingly to reduce the likelihood of plugging. For example, the operator can implement one or more of the remedial actions described above.

Additional structures can also be provided for clearing and/or preventing blockage of the vacuum passage 47. For example, nozzle jets can be provided at the drill head for directing spray at the entrance to the passage 47. Also, blockages can be mechanically cleared by mechanical structures such as rods/snakes passed axially through either of the passages 43, 47.

E. Example Control Interface

FIG. 14 shows an example embodiment of an interface suitable for use with the tunneling apparatus of FIGS. 1-13. As shown at FIG. 14, the user interface is a portable control unit capable of communicating with the controller 50 by wireless communication technology or by a wired connection such as a tether. The portable nature of the depicted user interface of FIG. 14 allows a machine operator to operate the tunneling apparatus 20 from within the pit/shaft or from a more remote location (e.g., an above ground location outside of the pit/shaft).

Referring still to FIG. 14, the user interface is contained within a portable enclosure 520 (e.g., a box, housing, etc.). The portable enclosure 520 includes a base 522 and a cover 524 attached to the base 522 by a hinge or other structure. As shown in FIG. 14, the cover 520 is in an open position in which the interface can be readily accessed by a machine operator. The cover 520 can also be moved to a closed position in which the user interface is protected within the enclosure 520. A seal can be provided between the base 522 and the cover 524 for preventing moisture from entering the enclosure 520 when the cover 524 is closed.

Referring still to FIG. 14, the user interface includes a control panel arrangement 530 mounted within the base 522 of the enclosure 520 and a steering monitoring display device 532 mounted to an inside face of the cover 524. The control panel arrangement 530 includes a display 534 (see FIG. 17) including a screen display device 536, an indicator light panel 538 and rows 540 of buttons/keys. The control panel arrangement 530 also includes a plurality of control elements (e.g., knobs, buttons, switches, rocker switches, joysticks, levers, etc.) that can be manipulated by the machine operator to control operation of the tunneling apparatus 20. For example, the control components can allow the operator to: a) steer the tunneling apparatus; b) increase or decrease the amount of drilling fluid provided down the drill string; c) control the direction and speed of thrust applied to the drill string; d) provide emergency stopping of the vacuum or the drill; e) modify throttle settings for either or both of the engines 33, 404; f) switch between a drilling mode and a rod change mode; and g) control rotation speed and/or rotation direction of the cutting unit 34. All of the above control functions can be accomplished by the machine operator while the machine operator concurrently monitors operating parameters (i.e., operating characteristics) of the tunneling apparatus 20 on the screen display device 536. Example tunneling apparatus operating parameters include feedback information such as: a) the hydrostatic pressure of the rotational driver 32a; b) the hydrostatic pressure of the thrust driver 32b; c) the engine speeds of the engines 33, 404; d) the drilling fluid flow rate; e) the rotational speed of the cutting unit; f) the thrust speed of the drill string; g) the level of vacuum pressure of the vacuum line; h) the fuel levels of the engines 33, 404; and i) a position of the steering control joystick.

During operation of the tunneling apparatus 20, the machine operator can continuously monitor parameters/factors that are indicative of a precursor plugging condition of the vacuum channel. For example, the control panel arrangement 530 allows the operator to monitor the vacuum pressure as well as the drilling fluid flow rate while concurrently having access to the various machine controls listed above. In this way, when the operator notices a change in operating conditions indicative of a precursor plugging condition (e.g., a change in vacuum pressure or a change in the drilling fluid flow rate), the operator can immediately take a corrective action such as increasing or decreasing thrust, increasing or decreasing rotation, increasing drilling fluid flow rate or other corrective action so as to prevent a full blockage of the vacuum passage.

Referring still to FIG. 14, the steering monitoring device 532 is depicted as a screen display device capable of displaying a feed from the camera 60. It will be appreciated that screen display devices can include liquid crystal displays, plasma displays, active matrix displays, alphanumeric displays, emissive displays such as cathode ray tubes, or other display devices. The feed from the camera 60 can be a streaming video feed or a sequence of still shots. Preferably, the display shows a position where the laser 42 hits the target 44 thereby allowing the operator to monitor whether the drill string 24 is maintaining a proper line. If the operator notices that the drill string 24 has moved off line, as indicated by the laser 42 moving off of a center of the target 44, the operator can take corrective action by generating relative movement between the steering shell 36 and the main body 38 of the drill head through manipulation of one or more steering control elements provided at the control panel arrangement 530.

Referring to FIGS. 14-16, the control panel arrangement 530 includes various control elements for allowing an operator to control most functions of the tunneling apparatus 20. For example, the control panel arrangement 530 includes control members in the form of a steering joystick 550, a drill throttle switch 552, a vacuum throttle switch 554, a rod change switch 556, a rotation speed switch 558, a manual rotation control lever 560, a manual thrust/pullback control lever 562, an auto drill start button 564, an auto resume button 566, a drilling fluid control knob 568, an auto drill thrust/pullback control knob 570, an emergency vacuum stop button 572, an emergency drill stop button 574 and a strike alert/remote lockout alarm 576. As shown at FIG. 17, the row 540 of buttons (i.e., controller keys) provided on the display 534 include a strike alert test key 600, a strike alert alarm cancel key 602, a vacuum break valve open/close key 604, a drilling fluid on/off key 606, a remote lockout alarm cancel key 608, a service key 610 for accessing one or more diagnostic screens on the screen display device 536, an increase key 612 for increasing values or scrolling through options on the screen display device 536, a decrease key 614 for decreasing values or scrolling through options on the screen display device 536 and an enter key 616 for selecting options or clearing fault messages on the screen display device 536. The indicator light panel 538 can include lights such as an emergency drill stop indicator light, an emergency vacuum stop indicator light, an engine warning light, a remote lockout-locked mode light, a strike alert status light, a drilling fluid on light, a spoils storage tank full light, an engine caution light, a remote lockout processing light, an auto drill active light, a vacuum break valve closed/suction on light, a rod change mode active light and a remote lockout-run mode light.

Referring to FIG. 17, the screen display device 536 of the display 534 is capable of showing a main control screen as well as other diagnostic and informational screens generated by programming of the controller 50. The controller 50 can typically include a programmed computer network including one or more data processors, memory (e.g., for storing various parameters and settings) and other components. An example computer control system having components suitable for use in systems in accordance with the principles of the present disclosure is disclosed at U.S. patent application Ser. Nos. 12/252,879; 12/252,883; and 12/598,560, which are hereby incorporated by reference in its entirety.

The main control screen of the screen display device 536 is shown at FIG. 18. The main control screen provides the tunneling apparatus operator with a significant amount of feedback information relating to the various systems of the tunneling apparatus. The feedback information can be displayed in various forms such as numerical readouts, bar graphs, or other display formats. The feedback information can be derived from data generated by sensors used to monitor the operation of the various system components. Referring to FIG. 18, the main controller screen shows feedback information representative of a hydrostatic drive pressure 650 (in pounds per square inch or bar) of the rotational driver 32a, a hydrostatic drive pressure 652 (in pounds per square inch or bar) of the thrust driver 32b, an engine speed 654 of the main engine 33 (in rotations per minute), an engine speed 656 of the vacuum engine 404 (in rotations per minute), a drilling fluid flow rate 658 (in gallons per minute or liters per minute), a bar graph 660 indicative of the speed of the rotational driver 32a, a bar graph 662 indicative of the speed of the thrust driver 32b.

The main display also shows a percentage of atmospheric pressure 664 indicative of the vacuum pressure at a predetermined location (a reading location of one of the sensors 372) along the vacuum path that extends from the distal end of the drill string to the source of vacuum 65. As displayed, 100% equals atmospheric pressure and 0% equals a pure/complete vacuum. In other embodiments, the main display can include multiple vacuum readings corresponding to different pressure sensing locations along the length of the vacuum path (e.g., sensing locations at the drill head, at the transition from the drill string to the source of vacuum and at the source of vacuum). The main display also includes a percentage of thrust capacity in use 665, a main engine fuel gage 666, vacuum engine fuel gage 668 and a steering joystick position indicator 670.

The rod change switch 556 of the control panel arrangement 530 allows an operator to switch the tunneling apparatus 20 between a rod change mode (i.e., a break-out mode) and a tunneling mode. When in the tunneling mode, the vacuum break valve 402 connects the vacuum 65 in fluid communication with the vacuum passage 47 that extends through the drill string 24. Also, the valve 400 is open so that the fluid pump 63 is in fluid communication with the drilling fluid passage 45 defined by the drill string 24. Moreover, the vacuum engine 404, the main engine 33 and the hydrostatic drive pressures of the drives 32a, 32b are all set to provide maximum power when needed. For example, the vacuum engine 404 can be operated in a high idle mode and the drives 32a, 32b can be operated in high drive pressure modes. Additionally, the rotational driver 32a is set in a rotation mode in which the rotational driver 32a provides continuous rotation of the female rotational drive element 306 in either a clockwise or counterclockwise direction as determined by manipulation of the manual rotation control lever 560 or an auto rotation setting.

When the operator switches the tunneling apparatus 20 from the tunneling mode to the rod change mode via switch 556, a number of operations automatically are implemented by the computer control system of the tunneling apparatus. For example, the vacuum break valve 402 disconnects the vacuum 65 from the vacuum passage 47 of the tunneling apparatus 20. Also, the drilling fluid valve 400 closes to disconnect fluid communication between the fluid pump 63 and the drilling fluid passage 45 of the tunneling apparatus 30. Moreover, the vacuum engine 404 is automatically idled down to operate in a low idle mode. Furthermore, the hydrostatic rotational driver 32a and the thrust driver 32b are operated in low hydrostatic drive pressure modes. Moreover, the rotational driver 32a is set to an oscillation mode in which manipulation of the manual rotation control lever 560 causes the female drive element 309 to be oscillated back and forth about a central longitudinal axis that coincides with the central longitudinal axis of the drill string 24 to facilitate mating the female drive element 309 with a corresponding male torque transfer feature (e.g., a hex stub) of a pipe section desired to be added to the drill string.

To add a pipe section to a drill string, the tunneling apparatus is switched from the tunneling mode to the rod change mode. The rod change mode active light 642 illuminates when the rod change switch 556 is switched to the rod change mode. With the tunneling apparatus in the rod change mode, the drive unit 32 is disconnected from the proximal most pipe section of the string of pipe sections, and the drive unit 32 is retracted to a proximal most position. Thereafter, the pipe section desired to be added to the string is placed in coaxially alignment with the drill string as well as the female drive element 309 of the drive unit 34. The operator then presses the manual rotation control lever 560 causing the female drive element 309 to oscillate while concurrently pressing the manual thrust lever 569 causing the thrust drive 32b to move the drive unit 32 in a distal direction. As the drive unit 32 moves in the distal direction, the oscillation of the female drive element 309 facilitates mating the male torque transfer feature of the pipe section being added within the female rotational drive element 309. Continued distal movement of the drive unit 32 slides the male torque transfer feature of the pipe section being added into the female rotational drive element 309, and then causes the distal end of the pipe section being added to engage with the proximal end of the proximal most pipe section of the drill string. Oscillation by the rotational driver 32a of the drive shaft of the pipe section being added facilitates mating the male torque transfer feature at the proximal end of the proximal most pipe section within a corresponding female torque transfer feature provided at the drive shaft adjacent the distal end of the pipe section being added. In this way, engagement between the distal end of the pipe section being added and the proximal end of the proximal most pipe section is facilitated. After the pipe section being added and the proximal most pipe section are latched together, the operator can switch the rod change switch 556 back to the thrust mode and tunneling operations can resume.

To steer the tunneling apparatus 20, the operator can manipulate the steering joystick 550 to cause relative movement between the main body 38 of the drill head and the steering shell 36. By monitoring the position of the laser 42 relative to the target 44 on the steering monitoring device 532, the operator can determine how the drilling unit should be steered. During steering, the position of the joystick is shown on the steering joystick position indicator on the main control screen of the screen display device 536.

To control rotation of the cutting unit 34, the operator can manipulate the manual rotation control lever 560. Upward movement of the manual rotation control lever 560 from a neutral position progressively increases the rotational drive speed of the cutting unit 34 in a counterclockwise direction, while downward movement of the manual rotation control lever 560 from the neutral position progressively increases the rotational drive speed of the cutting unit 34 in a clockwise direction. The rotation speed switch 558 allows different ranges of rotational drive speeds to be selected. For example, a first position of the rotational speed switch 558 provides a high speed/low torque range, a second position of the rotational speed switch 558 provides a medium speed/medium torque range, and a third position of the rotational speed switch 558 provides a low speed/high torque range. The exact speed within a given selected range is controlled by the position of the manual rotation control lever 560. Once a productive speed has been determined, the operator can press the auto drill start button 564 which activates an auto drill mode in which the desired rotational drive speed is automatically maintained when the operator releases the manual rotation control lever 560. Once the rotational drive speed has been set in the auto drill mode, the amount of thrust supplied to the drill string by the thrust driver 32b is set by the auto drill thrust/pullback control knob 570. After tunneling has been stopped to add another pipe section to the drill string, the rotational drive speed can be automatically re-set to the previously saved rotational drive speed by pressing the auto resume button 566.

The auto drill indicator light 638 illuminates solid when the auto drill mode is active, flashes when the auto drill mode is in standby (e.g., during a rod change) and is off when the auto drill mode is off. Manipulation of either of the levers 560, 562 after the auto drill mode has been set, terminates the auto drill mode and resets the system to a manual control mode. The screen display device 536 also shows the percentage of total available thrust being utilized at a given moment in time.

The manual thrust/pullback control lever 562 is used to control the thrust or pullback applied to the drill string when the tunneling apparatus 20 is not in an auto drill mode. For example, the manual thrust/pullback control lever 560 can be pushed upwardly from a neutral position to progressively increase the amount of thrust applied to the drill string and can be pulled downwardly from the neutral position to progressively increase the amount of pullback applied to the drill string. The drilling fluid control knob 568 can be used to control the amount of drilling fluid provided to the drill string by the pump 63. For example, by rotating the knob counterclockwise, the flow rate of the drilling fluid is increased, and by rotating the drilling fluid control knob 568 clockwise, the flow rate of the drilling fluid provided to the drill string is decreased. As indicated above, the flow rate of the drilling fluid is displayed on the screen display device 536. Additionally, the drilling fluid indicator light 630 illuminates when drilling fluid is being provided to the drill string.

The drill throttle switch 552 and the vacuum throttle switch 556 respectively allow the main engine 33 and the vacuum engine 404 to be manually set at either a high throttle setting or a low throttle setting.

Embodiments of the present disclosure can use memory coupled to a control processor to perform the methods and functions described here. Memory can be a computer readable medium encoded with a computer program, software, computer executable instructions, instructions capable of being executed by a computer, etc., to be executed by circuitry, such as central processor and/or machine controller. For example, memory can be a computer readable medium storing a computer program, execution of the computer program by central processor causing reception of one or more signals from sensors, measurement of the signals, calculation using one or more algorithms, and outputting of control signals to the various motors, valves, pumps and other machine components disclosed herein. Output from the computer/central processor can also be used to control the content and appearance of the screens displayed by the screen display devices disclosed herein.

From the foregoing detailed description, it will be evident that modifications and variations can be made in the devices of the disclosure without departing from the spirit or scope of the invention.

CONTROL SYSTEM AND INTERFACE FOR A TUNNELING APPARATUS

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