US3814481A

US3814481A - Intermittent advancing device for a rotatable boring machine

Info

Publication number: US3814481A
Application number: US00251141A
Authority: US
Inventors: M Montacie
Original assignee: BLANZY OUEST UNION INDLE
Current assignee: BLANZY OUEST UNION INDLE; UNION IND BLANZY QUEST FR
Priority date: 1971-06-14
Filing date: 1972-05-08
Publication date: 1974-06-04
Anticipated expiration: 1991-06-04

Abstract

Tool for a rotating head of a continuous boring or cutting machine, mounted on a tool-carrier fixed on the said rotating head and driven in a rotating sweeping movement in a plane passing through the axis of rotation of the said rotating head, performing regular work due to a discontinuous advance device, obtained by means linked to cylinders exerting a periodic thrust on the rotating head at each change in the direction of oscillation of the said tool-carrier.

Description

United States Patent [191 Montacie June 4, 1974 INTERMI'ITENT ADVANCING DEVICE FOR A ROTATABLE BORING MACHINE Marcel Montacie, Paris, France alie eak iqs fi fls flmr na Paris, France Filed: May 8, 1972 Appl. No.: 251,141

Related [15. Application Data Continuation-in-part of Serv No. 152,839. June 14., 1971, Pat. No. 3,773,387. which is a continuation-in-part of- Ser. No. 848,013 Aug. 6, i969, abandoned.

Inventor:

Assignee:

Foreign Application Priority Data May 7,1971 France 71.16654 [1.8. CI. 299/61 Int. Cl. v. EOlg 3/04 Field of Search 299/31, 85, 86, 6]

References Cited UNITED STATES PATENTS v Starr et al 299/3l X 6/l968 Hoever 299/86 X FOREIGN PATENTS OR APPLICATIONS 1,938,8l8 2/l970 Germany 299/86 Primary Examiner-Ernest R. Purser Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak 5 7 ABSTRACT Tool for a rotating head of a continuous boring or cutting machine, mounted on a tool-carrier fixed on the said rotating head and driven in a rotating sweeping movement-in a plane passing through the axis of rotation'of the said rotating head, performing regular work due to a discontinuous advance device, obtained by means linked'to cylinders exerting a periodic thrust on the rotating head at each change in the direction of oscillation of the said tool-carrier.

10 Claims, 3 Drawing Figures PATENTEDJuu 4:914

sum 1 or 3 FIG/B PATENTEDJuu 4 I974 sum 2 0F 3 FIGQ PATENTEDJUN 41974 1 1 483

sum

3 or 3 1 INTERMI'ITENT ADVANCING DEVICE FOR A ROTATABLE BORING MACHINE CROSS REFERENCES TO RELATED APPLICA- TIONS This application is a continuation-impart of copending application Ser. No. l52,839, filed June l4, l97l, which has subsequently matured into Pat. No. 3,773,387, issued Nov. 20, I973. Application Ser. No. l52,839 was in turn a continuation-in-part of copending application Ser. No. 848,013, filed Aug. 6, I969, and now abandoned.

The present invention relates to discontinuous advance devices as much for making continuous operation of the oscillating tools of a continuous boring or cutting machine easier as for making the regularity of the oscillating movement of the various tool-carriers and the synchronising of the said movements together easier.

Indeed, it is known that the thrust effort on a tool determines the depth to which the latter drives into the ground or the rock of the working face and the said driving in turn determines the resistance torque applied to the cutting head by the said tool.

The operating method used up till now consisted in exerting a continuous thrust on the boring head effecting a progressive driving in of the tools giving rise to peak resistance torques incompatible with the regular operation of the machine.

One of the objects of the present invention is to effect constant driving in of the tool enabling operation at a constant torque by the action of a then regular thrust. To do this, the advancing of the machine is effected in jerks at the end of each oscillation of the tool-carriers,

- as much towards the outside as towards the inside, that is, at the moment of the change in direction of the movement and, of course, to obtain that result, the tools mounted on the said rotating head must arrive at the end of their stroke at the same time, that is, they must be synchronised. the ones being in the position close to the axis of rotation of the said head, the others in the position furthest therefrom, so as to counterbalance the torques caused by the various tools as well as possible.

Lastly, the control device for reversing the movement of the tool-carriers, using end-of-stroke switches exposed at the front of the rotating head, gives rises to irregularities in operation connected with the risks resulting from the changing conditions of the ground,

. during operation to overcome these uncertainties, and

to simplify the control device for reversing the oscillating movement of the tool-carriers: on the one hand, the drive jacks for oscillation of the tool-carriers are supplied with fluid through a rotating connection enabling the use of a fixed control device placed in safety behind the machine, and on the other hand, reversing control is effected by a time-switch ensuring a given periodicity of the movements and independent from oscillation variations of the tool-carriers about their average value.

The present invention has for its object a tool for a rotating head of a continuous boring or cutting machine, mounted on a tool-carrier fixed to the said rotating head and driven with a rotational sweeping movement in a plane passing through the axis of rotation of the latter and on which means connected with thrust jacks exert periodic efforts producing a discontinuous advance of the said tool at each change in the direction of the oscillating movement of the said tool-carrier.

The aims and other advantages of the present invention will become apparent from the following description, which has no limiting character, of an example of an embodiment, with reference to the drawings in which:

FIG. 1 shows a boring head assembly with oscillating tool-carriers and a fixed hydraulic control system, acting through a rotating connection,

FIG. 2 shows the hydraulic diagramme of the sweeping device of a tool-carrier,

FIG. 3 shows hydraulic diagramme of the device for advancing by jerks or for controlling the thrust.

FIG. 1, the boring head I driven in a rotatingmovement in the direction shown by the arrow 2, by the shaft 3 on which it is fixed, is fitted with tools of the cutter wheel type 4, rotating on shafts 5 mounted on toolcarriers 6 oscillating on shafts 7 mounted on supports 8 fixed to the said head 1.

Cylinders 9 mounted for oscillation on trunions 10 drive the tool-carriers 6 in an oscillating movement by means of the rods 11 fast with the positions of the said cylinders 9; whereas a shaft 12 rotating in the toolcarrier 6 and crossed by the end of the rod 11 ensures the required fixing between the said rod 11 and the tool-carrier 6.

The rods 9 are connected to a fixed hydraulic control assembly 13, through a rotating connection 14 whose fixed part 15 is connected by fixed tubes 16 to the assembly 13 and whose rotating part 17 receives tubes 18 mounted on the rotating head I and connected to the jack cylinders 9, each of the tubes 18 being connected to the corresponding tube 16 to constitute the hydraulic circuit of the individual control devices for the jack cylinders 9.

The axes of the shafts 7 on which the tool-carriers 6 oscillate are perpendicular in space to the axis of rotation of the shaft 3 bearing the rotating head 1 and situated, in space, at an equal distance from the latter. Likewise, the

shafts

10 and 12 are perpendicular to the shaft 3 and the plane of symmetry of the tool-carriers 6 pass constantly during the oscillation of the latter through the axis of rotation of the shaft 3 and contains the rotation axis of the shaft 5 on which the tool 4 turns freely.

The tunnel 19 which has a toroidal working face 2 0 is cut away by four tools 4 each arranged so as to from a spiral cut in the

respective sections

20a, 20b, 20c and 20d, swept by them during their oscillation, whereas when there is no oscillation, the tools each form a circular cut as is known in machines where the tools are mounted fixed directly to the front of the rotating head.

The tool at the top of FIG. 1 follows the section 20a and the tool at the bottom follows the section 20b, each of these being shown in its positionfurthest from the axis, that is, at the moment when the oscillating direction changes.

Turning to FIG. 2, cylinder 9 is connected with its hydraulic control circuit, whose hydraulic oil, arriving through the tubes 16, passes in the tubes 18 after having crossed the rotating connection 14. It is a double acting jack cylinder in which the rod 11 of the piston 21 ensures the oscillating movement of the corresponding tool carrier 6, which is not shown. Each jack cylinder 9 is connected up to a pump having two

bodies

22 and 23 respectively whose cylinders correspond to the unequal volumes of the

chambers

24 and 25 respectively, the diflerence between the said two volumes being due to the rod 11 which moves in the chamber 24.

The shaft 26 of the double pump is, to great advantage, driven in a rotating movement in the direction of the arrow 27 by an independent electric motor, it being possible for one and the same electric motor to drive all the pumps of the various tool-carriers. It is evident that the double pump could be driven mechanically by the rotating of the head.

Distributors 28 having four channels, which are electrically operated by a winding 28a, are installed between the pumps and the jack cylinders to control the oil flow direction in the hydraulic circuit; thus, in FIG. 2, the rod 11 enters the jack cylinder 9 in the direction of the arrow 29 to move the corresponding tool away from the axis of the rotating head, under theeffect of the oil coming from the pump body 22, flowing through the distributor 28 in the direction of the arrow 30 and flowing in the tube 16 in the direction of the arrow 31, whereas the oil comes from an oil tank 32 subjected to a pressure in the order of one bar, passing as much through the central tube 33, through the non-return valve 34, as through the tube 35 and the distributor 28; appropriate arrows show the oil flow direction. Other non-return valves and pressure, limiters 36 complete the hydraulic circuit, whereas the tubes 33a shown in dotted lines are used for the scavenging of leakage oil. When the flow direction is reversed, the distributors 28 ensure the crossing of the hydraulic circuits symbolised by the oblique straight lines 37 marked with arrows at their ends to show the new flow direction. By this regulating of the pump discharge, the theoretical time of an outgoing or return stroke of the piston 21 of the jack cylinder 9 is regulated at a value T. By means of a time-switch device, the simultaneous reversing of the distributors 28 of the tool-carrier assembly 6 is affected at intervals of time To T+ I, I being a very short time in relation to T (in the order of 1 second) which enables the synchronisation of the oscillating of all the tool-carriers to be ensured, the rods 11 being blocked duringthe time t, by means of the pistons 21 abutting against one of the rings 38, whereas the pumps discharge at that instant through their pressure limiters 3.6.

The time-switch device controls the reversing of the distributors 28 by means of a contact switch equipped with one contact per tool-carrier6 to be controlled, the contact switch being of .the open or closed type; in these conditions, each contact controls respectively the de-energising and supplying of the windings 28a of the distributors28 assigned to the hydraulic control circuit of a same tool-carrier 6 so as to select the oscillating direction of the tool-carriers, the ones moving closer to the axis of rotation of the head in the direction of the

arrows

39a and 39b, the others moving away from it in the direction of 390 and 39d, as shown in FIG. 1. Actually, it is absolutely essential for the furthest sections a and 20b to be covered simultaneously in the same direction in relation to the axis of rotation of the rotating head.

Numerous variations of this hydraulic configuration are possible. Thus, double pumps with axial pistons can be used, and the reversing of the oil flow is effected by reversing the plate of the said pump, In the case where constant, taking into account the inertia of the as'sembly and the drive method by a redundant power motor.

The average oscillating frequency of the tool-carriers is also determined during manufacturing and in relation to the angular rotating speed of the head so as to make the tool form a cut having a spiral shape of given medium pitch on the working face whereas to take into account the variousworking parameters, more particularly the hardness of the rocks on the ground to be bored, the saidpitch can be adapted to the work required, by modifying the discharge of the control pumps of the jack cylinders 9, but the maintaining of that pitch,. that is, of the ratio between the rotating speed of the head and the sweeping speed of the tool ,carriers is not critical, for therotating speed being practically constant, and the sweeping speed being adjustable, a strict synchronising of these two movements is useless, and thus, they can be obtained by independentdrive means. I

Turning to FIG. 3, a hydraulic pump 40 having an adjustable discharge of 0 litres par second is driven in a rotating movement in the direction of the arrow 41 by an electric drive motor 42 and discharges into a hydraulic accumulator 43- whose inflation pressure is greater than that necessary for making the boring machine advance. A single hydraulic distributor 45 electrically controlled by a winding 45a and normally closed is mounted between the accumulator 43 and the thrust jack cylinders 44.

The jack cylinders 44 are mounted between the mobile structure supporting the rotating headl of the machine and the support points of the latter on the ground to be drilled so as to exert, on the said hea d,the required thrust.

At each reversing 'of the oscillating direction of the tool-carriers, the time-switch device for controlling the reversing of the tool-carrier oscillating direction by the four-channel electrodistributors 28 also controls, by means of time-delay relays, the opening'of the single electrodistributor 45 during a time which is adjustable between two and four seconds, enabling all of the oil stored in the accumulator 43 to pass into the jack cylinders 44, ensuring advancing in jerks.

Thus, at each reversing or backing away of the toolcarriers, the machine advances a certain distance connected simultaneously with the duration time T of a half-oscillation of the tool-carriers and with the adjustable discharge Q of the pump 40.

In the case of a cutting machine, the thrust on the rotating head is produced by means of the tracks on which the machine is mounted, these latter being driven by a hydraulic motor and the advancing by jerks of the said machine is then obtained by supplying the said hydraulic motor with oil from the accumulator 43 during the required discharging time of the latter.

This hydraulic advances control system is equipped with a general oil tank 46 at which the various oil circuits of the device, equipped, moreover, with

pressure limiters

47 and 48,

non-retum valves

49 and 50, end stop cocks 51 used for isolating the accumulator 43.

What is claimed is: is:

l. A discontinuous advancing device for a continuous boring or cutting machine having a continuously rotatable head and tool means mounted for oscillation on said head for movement in a rotating sweeping movement in a plane passing through the axis of rotation of said rotatable head, comprising thrust jack cylinder means mounted on said machine in engagement with said head and hydraulic means for periodically operating said cylinder means for exerting a thrust on said head at each change in the oscillating direction of said tool means.

2. A discontinuous advancing device according to claim 1 wherein said hydraulic means comprises a hydraulic accumulator, conduit means, connecting said accumulator to said cylinder means and electrically operated valve means for periodically controlling the discharge of said accumulator into said thrust jack cylinder means.

3. A discontinuous advancing device according to claim 1 wherein said hydraulic means comprises a hydro-pneumatic pressure multiplier, conduit means connecting said multiplier to said cylinder means including electrically operated valve means for controlling the thrust jack cylinder means.

4. A discontinuous advancing device accordingto claim 1 and further comprising double acting hydraulic cylinder means for oscillating said tool means, a fixed hydraulic control device, rotating connection means connecting said control device to said double acting hydraulic cylinder means, said control device comprising a pump, hydraulic electro-distributor inverter means for controlling said double acting hydraulic cylinder means, switch means, and circuit means including said switch means for controlling the operation of said double acting hydraulic cylinder means.

5. A discontinuous advancing device according to claim 4 wherein said hydraulic means comprises a hydraulic accumulator, conduit means connecting said accumulator to said thrust jack cylinder means, and electrically operated valve means for periodically controlling the discharge of saidaccumulator into said thrust jack cylinder means; and

- wherein said switch means simultaneously controls said hydraulic electro-distributor inverter means to control the oscillating movement of said tool means and said electrically operated valve means for periodically controlling the discharge of said accumulator into said-jack cylinder means.

6. In a continuous drilling or boring machine having a boring head rotatable about an axis and at least one cutting tool mounted on a tool holder for oscillatory sweeping movement in a plane passing through the axis of rotation of said boring head, the improvement comprising:

means having a thrust jack for exerting a periodic thrust to effect a discontinuous advance of the tool upon each change in direction of oscillation of the tool holder.

7. A machine according to claim 6, wherein the discontinuous advance is effected by a hydraulic accumulator associated with an electric control cock and discharging periodically in the thrust jack.

8. A machine according to claim 6, wherein the discontinuous advance is provided by a hydro-pneumatic pressure multiplier associated with an electric control cock placed in the supply circuit for the thrust jack.

9. A machine according to claim 6 comprising a plurality 'of cutting tools mounted on oscillatable tool holders; and wherein each of the tool holders is oscillated by a double-action hydraulic jack acting on the tool holder, at fixed hydraulic control device is connected to each jack through a turning joint; a pump is connected to each jack and the turning joint through a hydraulic inverter electro-distributor; and means is provided for synchronizing the movement of the tool holders, said synchronizing means comprising a timer periodically energizing the coil of a contactor having supply contacts for the excitation coils of the distributors, and mechanical stops arranged in the jacks.

10. A machine according to claim 9 wherein an excitation coil of an electric cock controls the periodic advance of said boring head, and the timer that controls the electro-distributors simultaneously ensures the short-duration supply of said cock coil through timed contact therewith.

Claims

1. A discontinuous advancing device for a continuous boring or cutting machine having a continuously rotatable head and tool means mounted for oscillation on said head for movement in a rotating sweeping movement in a plane passing through the axis of rotation of said rotatable head, comprising thrust jack cylinder means mounted on said machine in engagement with said head and hydraulic means for periodically operating said cylinder means for exerting a thrust on said head at each change in the oscillating direction of said tool means.

4. A discontinuous advancing device according to claim 1 and further comprising double acting hydraulic cylinder means for oscillating said tool means, a fixed hydraulic control device, rotating connection means connecting said control device to said double acting hydraulic cylinder means, said control device comprising a pump, hydraulic electro-distributor inverter means for controlling said double acting hydraulic cylinder means, switch means, and circuit means including said switch means for controlling the operation of said double acting hydraulic cylinder means.

5. A discontinuous advancing device according to claim 4 wherein said hydraulic means comprises a hydraulic accumulator, conduit means connecting said accumulator to said thrust jack cylinder means, and electrically operated valve means for periodically controlling the discharge of said accumulator into said thrust jack cylinder means; and wherein said switch means simultaneously controls said hydraulic electro-distributor inverter means to control the oscillating movement of said tool means and said electrically operated valve means for periodically controlling the discharge of said accumulator into said jack cylinder means.

6. In a continuous drilling or boring machine having a boring head rotatable about an axis and at least one cutting tool mounted on a tool holder for oscillatory sweeping movement in a plane passing through the axis of rotation of said boring head, the improvement comprising: means having a thrust jack for exerting a periodic thrust to effect a discontinuous advance of the tool upon each change in direction of oscillation of the tool holder.

9. A machine according to claim 6 comprising a plurality of cutting tools mounted on oscillatable tool holders; and wherein each of the tool holders is oscillated by a double-action hydraulic jack acting on the tool holder, a fixed hydraulic control device is connected to each jack through a turning joint; a pump is connected to each jack and the turning joint through a hydraulic inverter electro-distributor; and means is provided for synchronizing the movement of the tool holders, said synchronizing means comprising a timer periodically energizing the coil of a contactor having supply contacts for the excitation coils of the distributors, and mechanical stops arranged in the jacks.