US3339646A

US3339646A - Sonic driving system for bendable lines

Info

Publication number: US3339646A
Application number: US429490A
Authority: US
Inventors: Jr Albert G Bodine
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-02-01
Filing date: 1965-02-01
Publication date: 1967-09-05
Anticipated expiration: 1984-09-05

Description

sept. 5, 1967 A G, BOBINE, JR 3,339,646

. SONIC DRIVING SYSTEM FOR BENDABLELINES Filed Feb. 1, 1965 4 sheets-Sheet 1 RESERVOR ATTORNEY Siept. 5, 1967 A. G. BOBINE, JR

SONIC DRIVING SYSTEM FOR BENDABLE LINES 1965 4 Sheets-Sheet 2 Filed Feb.

NVENTOR.

' ALBERTG. BOD|NE,JR. BY

ATTORNEY sePf- 5, 1967 y A. G. BOBINE, 1R 3,339,646

SONIC DRIVING SYSTEM FOR BENDABLE LINES Filed Feb` l, 1965 4 Sheets-Sheet 5 FIG. 3

iwf/@4.4%

ALBERT G. BODINE, JR.

ATTORNEY Sept 5, 1967 A, G; BOBINE, JR

SONIC DRIVING SYSTEM FOR BENDABLE LINES 4 Sheets-Sheet 4 Filed Feb.

INVENTOR.

ALBERT G. BODINE, JR.

FIG. 6

ATTORNEY United States Patent O 3,339,646 SONIC DRIVING SYSTEM FOR BENDABLE LINES Albert G. Bodine, Jr., 7877 Woodley Ave., Van Nuys, Calif. 91406 Filed Feb. 1, 1965, Ser. No. 429,490 Claims. (Cl. 175-62) ABSTRACT oF THE DrscLosURE A line to be driven through the ground horizontally is passed through a roller guide mechanism which guides it from a generally Vertical ground entry angle to the desired horizontal drive direction. Sonic vibrational energy s applied to the line, to cause elastic vibration thereof, by means of a mechanical sonic oscillator which is carried up and down on guide tracks along with means for driving the line through the roller guide mechanism. The sonic energy stress relieves the line material and reduces friction, thereby making such material readily yieldable to the bending force and facilitating the movement of the line through the ground.

This invention relates to. a sonic driving system for bendable lines, and more particularly to such a system for facilitating the routing of such lines through the ground.

Lines such as power and telephone cables and water conduits often have to be routed underground in situations where the tearing up of the surface for such routing is impossible or at best inconvenient and expensive. It sometimes is feasible to route lines through the ground by burrowing or trenching techniques. The burrowing of lines, however, often poses a formidable task, especially where pavement, buildings, hard earth and/or rock conditions are encountered.

It has been found, as described in my co-pending application Serial No. 198,783, filed May 31, 1962, that lines can be driven through the ground with relative ease if while being so driven they are excited with sonic vibrations preferably at a frequency which sets up a resonant vibration of such lines. Such sonic vibrations effectively iluidize granular earth and penetrate rock material by virtue of the elastic fatigue, caused both by the cyclic compressional and tension states induced therein, thus making for reduced wall friction and a clear path for the conduit to progress therethrough. Along these lines, my Patent No. 2,975,846 describes the use of such techniques for driving piles.

The device and method of this invention provide improved means for utilizing sonic techniques in driving lines underground whereby such lines can be driven into the ground from the surface at an angle relative to the horizontal direction in which the line is to be driven and then bent back to assume the desired horizontal direction. The sonic energy is utilized in the device and method of this invention in implementing the bending operation in addition to its function in penetrating and lluidizing the ground. The provision of means for enabling entry into the ground from above has two primary advantages.

First, the need for a large lead area is eliminated as there A is no need to dig a ditch or trench to enable the initial feeding of the line at a point below the normal ground level in the desired horizontal direction. Secondly, a vertical component is added to the driving action thus adding the force of gravity to the force bias, to aid in the driving of the line.

The desired end results are achieved in the device and method of the invention by providing a forming path such as a roller guide mechanism which guides the line from its ground entry angle to the desired horizontal Hce drive direction. Such curving of the line by the guide mechanism is facilitated by virtue of sonic vibrations applied to the line preferably at substantially a resonant frequency thereof to stress relieve the line material, and to reduce friction through the forming path, thereby making such material readily yieldable to the bending force. Sonic vibrations are applied to the line by means of a mechanical sonic oscillator which is carried up and down on guide tracks along with the means for driving the line through the roller guide mechanism.

It is therefore an object of this invention to facilitate the running of lines through the ground.

It is a further object of this invention to enable the running of lines through the ground from a starting position at ground surface.

It is still another object of this invention to provide a device and method whereby sonic energy is utilized to enable the driving of a line horizontally through the ground in a starting direction which is at an angle with respect to the ground surface.

It is -still a further object of this invention to minimize the lead area required for driving lines through the ground.

It is still another object of this invention to provide a method and device for utilizing sonic energy to both drive a line through the ground and to bend such line so that its direction of travel is changed from an initial direction.

Other objects of this invention will become apparent from the following description taken in connection with the accompanying drawings, of which:

FIG. l is a schematic View illustrating the device of the invention in operation,

FIG. 2 is an elevation View, partially in cross section, illustrating an oscillator mechanism that may be utilized in the device of the invention,

FIG. 3 is an elevation view partially in cross section illustrating a preferred embodiment of a power drive and bending mechanism which may be utilized in the device of the invention,

FIG. 4 is a cross-sectional view taken along the plane indicated by 4-4 in FIG. 3,

FIG. 5 is an elevation cross-sectional view of the collar cla-mp release mechanism utilized in the drive mechanism illustrated in FIG. `3,

FIG. 6 is a cross sectional view of a mandrel mechanism which may be utilized to facilitate the driving of flexible conduit with the device of the invention, and

FIG. 7 is a schematic drawing of a hydraulic control system which may 4be utilized with the device of the invention.

In order to properly analyze the device of the invention Iit is helpful to resort to an analogy between an electrical oscillating resonant circuit and a mechanically vibrating elastic resonant circuit. 'The use of such an analogy is well known to those skilled in the art and is described for example in Chapter 2 of Sonics by Hueter and Bolt, published lin 1955 by'lohn Wiley and Sons. Thus, driving force, F, is analogous to voltage, E, velocity of vibration, u, is analogous to electric current, z', compliance, Cm, is analogous to capacitan-ce, Ce, Mass, M, is analogous to inductance, L, and mechanical resistance such as friction, Rm, is analogous -to electrical resistance, R. By such an analogy, it can be shown that if a member is elastically vibrated by a sinusoidal force, F0 sin wT that where,

Zm=the mechanical impedance of the member being driven Rm=the effective mechanical resistance of the circuit being driven M :the mass of the object being driven Cm=the effective elastic compliance of the object being driven u--velocity of vibration of object w=21rf, where f is equal to the frequency of vibration.

Where, 1M is equal to 1/ wCm, a resonant condition eX- ists, and the effective mechanical impedance, Zm, is equal to the mechanical resistance, Rm, the reac-tive impedance components, wM and 1/ wCm, lcancelling each other out. Under such a resonant condition, velocity of vibration, u, is at a maximum, effective power factor is unity, and energy is most efficiently delivered to the object being Vibrated. It is such a high eficien-cy resonant condition in the line -being driven that is preferably utilized in the method and device of this invention to achieve the desired end results.

It is to be noted by reference to Equation 1 that velocity of vibration, u, is highest where impedance, Zm, is lowest and vice versa. Therefore, a high impedance load will tend to vibrate at relatively low velocity and vice versa. At an interface Ybetween high and low impedance elements, a high relative movement results by virtue of such impedance 4mismatch which is in `an electrical circuit results in a high reected wave. On the other hand, energy is most efficiently transmitted through matched impedance elements, just as in an electrical circuit.

As the sharpness of .resonance of an electrical circuit is determined by the Q of the circuit (indicative of the ratio of energy stored to the energy used in each cycle), so also the Q of a mechanical resonant circuit has the same significan-ce and is equal to the ratio between wM and wRm. Thus, a high Q resonantly Vibrating system is capable of producing considerable cyclic motion.

It can also be shown that the acceleration of a sinusoidally vibrating mass is a function of the square of the frequency of vibration. Thus, even at moderately high vibration frequencies, very high accelerations and forces can be achieved.

lt should be constantly kept in mind when considering Equation l that this equation represents the total effective resistance, mass, etc., in the mechanical circuit driven by the oscillator and the parameters indicated are generally distributed throughout the system rather than being lumped in any one component or portion thereof.

Referring now to FIG. 1, a schematic drawing illustrating the operation of the device of the invention is shown. Conduit 11 which is t-o be driven through the ground 18 is fed through oscillator and hold-release -assembly 15 in au initial direction which is at an angle with respect to the ground surface plane. From oscillator and holdrelease assembly 1S, conduit 11 is fed through roller `guide assembly 17 where it is bent from its initial direction of travel to a final direction of travel substantially parallel to the ground surface plane. Roller guide assembly 17 includes support apron 64 which has a channel 22 formed therein for guiding the conduit and rollers 69 for facilitating the passage of the conduit through the channel.

Mechanical oscillator and hold-release mechanism 15 is fixedly mounted on .carriage 16, and carriage 16 is slidably supported on support frame 14. Drive mechanism 19 reciprocally drives carriage 16 in the directions indicated by arrows 25. Means are provided in mechanical oscillator and hold-release assembly 15 for grabbing conduit 11 during the downward travel of carriage assembly 16, and releasing such conduit during the upward travel the-reof, thereby driving the conduit downwardly in the initial direction of travel.

A mechanical oscillator is included in assembly 15 for imparting mechanical vibrations to conduit 11 along the longitudinal -axis thereof. Such vibrations may be in the sonic frequency range of, for example, between 300 and 500 cycles per second. Such vibrations are preferably of a frequency which will cause resonantvibration of conduit 11 whereby standing waves are set up in the line.

Under such resonant conditions, as can be seen from Equation 1, the effective compliant reactive and mass reactive components cancel each other out so that the effective mechanical impedance, Zm, is equal to the rnechanical resistance, Rm. This provides for maximum velocity of vibration, u, with most efficient transfer of vibration energy to the conduit. The high enengy vibration of conduit 11 stress relieves the material of the conduit so that it is readily bent in roller guide mechanism 17 to change its direction of travel as desired, and at the same time effectively fluidizes the ground through which the conduit passes by virtue of the elastic fatigue and liuidization in the earthen material caused by the cyclic compressional land tension states induced therein. The vibration of the conduit also facilitates passage of sa-me through the roller guide mechanism, this by virtue of the high relative vibrational motion between the two, This results from the impedance mismatch at the interface between the resonant low impedance conduit and the relatively high impedance earth supported guide mechamsm.

As the effective length of conduit 11 increases as it is driven further into the ground, the frequency of the orbital mass oscillator tends to automatically adjust with the changing load to the resonant frequency thereof thus assuring optimal operation with standing waves of multiples of a half wavelength present along the line at all times. The oscillator has a low impedance, high velocity output, and thus, vibration velocity (u) antinodes tend to appear at the oscillator and at the far end of the line. This provides a high velocity low impedance condition at the driving end of the line. ln view lof the high impedance presented by the high mass earth, the earth mass, while being effectively stressed by the vibration energy, tends to vibrate at a relatively low velocity as compared with the end of the line. This high relative movement between the line and the earth tends to enhance the fluidation of the soil and passage of the line therethrough.

Referring now to FIG. 2, a mechanical oscillator that may be utilized in the device of the invention is illustrated. The os-cillator shown in FIG. 2 is similar in configuration to that described in my aforementioned copending application Serial No. 198,783. This ty-pe of orbiting mass oscillator has the unique property of automatically adjusting its rotation frequency with load changes to maintain resonant vibration of the load. The oscillator, in effect, becomes part of the resonant circuit and tends to lock in at the resonant frequency of t-he vibrating member being driven thereby.

Power plant 20 which is mounted on support frame 21, and which may include a gasoline engine, provides output arotation of shaft 23. Shaft 23 is connected t-o rotatably driven lgear wheel 24a. Gear wheel 24a iS coupled to rotatably drive gear wheel 24b in an opposite direction. Thus output coupling 26a which is connected to gear lwheel 24a is rotatably `driven in a first direction, and output coupling 2Gb which is connected to gear Wheel 24b is rotatably driven in an opposite direction. Coupling shaft 32a is connected to -gear coupling 26a by means of universal joint 30a. Coupling shaft 32a is slidably mounted within tubular shaft 33a to form a slip spline joint therewith such that shaft 32a rotatably drives shaft 33a but so that the two shafts can move relative to each other along their longitudinal axes. Gear coupling 2Gb, universal joint 30b, coupling shaft 32b and tubular drive shaft 33b are similar in configuration to the similarly identified

units

26a, 30a, 32a and 33a, just described.

Shafts

33a and 33b are coupled by means of universal joints 35a and 35h respectively to associated gear shaft 41a and 41b. Fixedly attached to gear shaft 41a is gear Wheel 38a and fixedly attached to :gear shaft 41b is gear wheel 38h. Rotors 40a and 40h are rotatably mounted on their associated gear shafts 41a and 41b.

Gear wheels

38a and 38b ride around on ring gears 37a and 37b respectively, which are attached to the inner walls of associated raceways 39a and 3919 formed in casing 42. Rotors 40a and 40b are carried along with their associated gear wheels and gear shafts, gear shafts 41a and 41b rolling around

respective pins

46a and 46b formed in case 42. Rotors 40a and 40b thus are rotated about their associated raceways 39a and 39h.

The rotors are initially positioned so that lthey will produce substantially equal and opposite forces on casing 42 when in the position indicated in FIG. 2 and positions 180 removed therefrom but will produce additive forces when they are in positions 90 removed from the position indicated in FIG. 2 (such as shown, for example, in FIG. 3). Thus, as best can be seen by reference to FIG. 3, strong vibrational oscillations are produced in casing 42 along the longitudinal axis of oon-duit 11 with vibrational forces normal to this axis being substantially cancelled out.

Referring now to FIGS. 3 and 4, a carriage and hydraulic drive mechanism which may be utilized in the device of the invention is illustrated. Oscillator and holdrelease mechanism 15 is mounted on cam'age 16. Casing 42 of the oscillator is supported on the carriage by means of

vibration isolators

43a and 43b an-d 44 which minimize the transfer of vibration energy from the oscillator to the adjacent components.

Isolators

43a and 43b and 44 may be of neoprene or any other suitable isolating material.

Carriage 16 has a pair of guide channels 66a and 66b formed along opposite edges thereof. Fixedly attached to frame member 14 are

tracks

67a and 67b on which guide channels 66a and 6617 are slidably iitted. Hydraulic jacks 48a and 48h are fixedly mounted on frame 14 by means of clamps 52a and 52b. The drive rods 50a and 50b of these jacks are attached at the ends thereof to carriage 16. When jacks 48a and 48h are appropriately actuated, as to be explained in connection with FIG. 7, carriage 16 is reciprocally driven up and down along the guide tracks 67a and 67b. The direction of drive is automatically reversed when carriage 16 strikes limit switches 60a and 88a mounted on the frame, and similar limit switches 60'b and 8812 (not shown) at the end of downward travel.

Collet clamp mechanism 45, which is described in detail in connection with FIG. 5, is provided to grab conduit 11 during the downward travel of carriage 16 and to release the conduit during the upward travel of the carriage. The conduit is thus driven in a downward direction by .the carriage mechanism. It is to be noted that such downward drive has the additional force of gravity behind it, in addition to the force provided by the jacks 48a and 48h, this as contrasted with the initial horizontal drive described in my co-pending application Ser. No. 198,783.

Referring now to FIG. 5, the details of the collet clamp mechanism 45 are shown. As to be explained in connection with FIG. 7, this mechanism operates in response to a hydraulic control, the same control which operates the

jack

48a and 48b. Collet clamp mechanism 45 is attached to oscillator casing 42, the mechanical vibrations of the oscillator thus being transmitted to the casing 72 of the collet clamp mechanism. Mounted in casing 72 is conical slotted collet 71 which includes a plurality of resilient fingers 71a. Casing 72 is mounted on carriage 16 on vibration isolator 44, thus preventing the dissipation of the vibration energy of the oscillator in the surrounding equipment. Slidably mounted in casing 72 is cam member 75 which is externally concentric with collet 71.

While carriage 16 is being driven downwardly, a hydraulie input signal is fed through line 78 to channel 80 so to drive cam member 75 to the right as shown in FIG.

5. In this position, cam surface 73 of cam member 75 v inwardly compresses fingers 71a so that they tightly grab the conduit 11, thereby holding such conduit to the carriage mechanism as it is moving downwardly. When the carriage reaches the end of its downward travel, the hydraulic drive is reversed to provide a hydraulic input in line 77 to channel 79 to drive cam member 75 to the left. In such position, cam surface 73 no longer depresses fingers 71a, and the conduit is thus released during the upward travel of the carriage mechanism. O ring seals 82 are provided to prevent hydraulic leakage. The vibration energy generated by the oscillator is transmitted from oscillator casing 42 through collet casing 72 and collet ngers 71a to lconduit 11.

Referring now to FIG. 7, a hydraulic control system i which may be utilized to implement the hydraulic drive and hold-release mechanism is illustrated. The hydraulic action is started by closing electrical switch 87. This connects electrical power from generator 86 to the arms of limit switches 60 and 88. During the downward travel of the carriage, limit switch 88 is closed (as shown in the figure) and provides power to, solenoid valve 90a. With solenoid valve 90a actuated, hydraulic uid is pumped from reservoir 84 by pump 83 through line 93 and the solenoid valve to

lines

54a, 54b and 78. The fluid in

lines

54a and 54b drives jacks 48a and 48h so as to provide downward travel of carriage 16. The fluid drive in line 78 provides the drive signal for cam member 75 causing the conduit 11 to be held to the carriage mechanism as explained in connection with FIG. 5. When the carriage mechanism reaches the end of its downward travel, switch 60 is closed and switch 88 is opened by virtue of mechanical actuation by carriage 16. This causes solenoid valve 90b to be energized and solenoid valve 90a to be deenergized. Under such conditions, hydraulic drive is provided through solenoid valve 90b to

lines

55a and 55b to reverse the direction of

jacks

48a and 48b, thus causing the carriage mechanism to be driven upwardly. Simultaneously, hydraulic drive is provided through line 77 to drive cam mechanism 75 as described in connection with FIG. 5, so as to release the conduit. In this fashion, the conduit is automatically driven downwardly by virtue of the reciprocating movement of the carriage mechanism.

Referring now to FIG. 6, a mandrel device is shown which may be utilized with the device of the invention where a flexible conduit such as a plastic line is to be driven through the ground. Mandrel member 102, which is .preferably metallic and while bendable in the guide mechanism of the device of the invention, has a rigid quality, is inserted into flexible line 101. The end of the line is capped by means of capping assembly which provides a strong drive point and which prevents dirt and other foreign matter from entering the hollow conduit. Capping assembly 100 includes an external capping member 103, the end of which grips the outer wall of conduit 101 and an inner member 104 which grips the inner wall of the conduit. Inner and

outer members

103 and 104 may be joined together by spot welding or any other suitable means. Mandrel 102 is preferably of a metallic material having high vibration efficiency (high Q) to enable most effective utilization of the vibration energy.

The device and techniques of this invention thus provide a simple yet highly elective means for driving a conduit through the ground with an initial downward travel direction. The use of such an initial downward drive obviates the necessity for making a large excavation as required with completely horizontal drive techniques and greatly facilitates the entire operation.

While the device and method of the invention have been described and illustrated in detail, it is to be clearly understood that this is intended by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of this invention being limited solely by the terms of the following claims.

I claim:

1. A device for driving a bendable elongated line through the ground comprising guide means for bending said line to change the direc- 7 tion of travel thereof from a first initial direction to a second final direction,

means for driving said line in said initial direction, and

sonic oscillator means for vibrating said line to both fluidize the ground through which said line is being driven and to stress relieve the material from which said line is fabricated so as to facilitate the bending of said line.

2. The device as recited in claim 1 wherein the'output frequency of said oscillator is such as to vibrate said line resonantly.

3. A device for driving a through the ground comprising guide means for bending said line to change the direction of travel thereof from an initial direction at an angle with respect to the ground surface plane to a final direction substantially parallel to the ground surface plane, said guide means including a curved guide channel for said line,

means for driving said line in said linitial direction, and

sonic oscillator means for vibrating said line resonantly to both uidize the ground through which said line is being driven and to stress relieve the material from which said line is fabricated so as to facilitate the bending of said line.

4. A method for driving a ground comprising driving the line downwardly from the ground surface at an angle with respect to the ground surface plane,

bending said line from its downward drive angle to a desired final drive direction, and

while said line is being driven, applying sonic vibrations thereto to simultaneously fluidize the ground through which the line is being driven and to stress bendable elongated line bendable line through the relieve the material from which said line is fabri-V cated so as to facilitate the bending of said line from its downward drive angle to the desired final drive direction.

5. The method as recited in claim 4 wherein said line is vibrated at a frequency which causes resonant vibration thereof.

6. A device for driving a bendable line through the ground comprising roller guide means for bending said line from an initial direction of travel downward from the surface of theY ground to a direction of travel substantially parallel to the surface of the ground,

means for driving said line downwardly through said roller guide means, and

mechanical sonic oscillator means for resonantly vibrating said line, whereby the vibrations in said line effectively fluidize the ground through which the line is being driven and stress relieve the material from 8 which said line is fabricated so as to facilitate the bending of said line.

7. A device for driving a ground comprising roller guide means for bending said line from an initial direction of travel downward from the surface of the ground to a direction of travel substantially parallel to the surface of the ground,

means for driving said line downwardly through said roller guide means including a carriage mechanism, means for slidably supporting said carriage mechanism for reciprocal motion along an axis extending in substantially the initial direction of travel of said line, means for driving said carriage mechanism reciprocally along said axis, clamp means fixedly mounted on said carriage mechanism and means for actuating said clamp means to clamp said line to said carriage mechanism when said carriage mechanism is moving downwardly and to release said line from said carriage mechanism when said carriage mechanism is moving upwardly, and

mechanical sonic oscillator means for vibrating said line,

whereby the vibrations in said line effectively fluidize the ground through which the line is being driven to facilitate the bending of said line.

8. The device as recited in claim 7 wherein said mechanical oscillator means is mounted on said carriage mechanism and connected to vibrationally drive said clamp means.

9. The device as recited in claim 7 wherein said oscillator means vibrates said clamp means and said line at a frequency which is substantially the resonant frequency of the effective impedance presented thereby.

10. The device as recited in claim 7 wherein said means for reciprocally driving said carriage mechanism comprises a fluid drive system, said means for actuating said clamp means being connected to operate in response to said drive system.

bendable line through the References Cited UNITED STATES PATENTS 2,296,161 9/1942 Hall 175-82 X 2,548,616 4/1951 Priestman et al. 175-103 2,644,669 7/1953 Curtis et al. 175-61 X 2,942,849 6/ 1960 Bodine 175-55 2,975,846 3/ 1961 Bodine 175-19 3,116,781 1/1964 Rugeley et al. 175-103 X 3,182,732 5/1965 Earnest 175--62 X CHARLES E. OCONNELL, Primary Examiner.

R. A. FAVREAU, Assistant Examiner.

Claims

1. A DEVICE FOR DRIVING A BENDABLE ELONGATED LINE THROUGH THE GROUND COMPRISING GUIDE MEANS FOR BENDING SAID LINE TO CHANGE THE DIRECTION OF TRAVEL THEREOF FROM A FIRST INITIAL DIRECTION TO A SECOND FINAL DIRECTION, MEANS FOR DRIVING SAID LINE IN SAID INITIAL DIRECTION, AND SONIC OSCILLATOR MEANS FOR VIBRATING SAID LINE TO BOTH FLUIDIZE THE GROUND THROUGH WHICH SAID LINE IS BEING DRIVEN AND TO STRESS RELIEVE THE MATERIAL FROM WHICH SAID LINE IS FABRICATED SO AS TO FACILITATE THE BENDING OF SAID LINE.