US3133469A

US3133469A - Device for axial displacement of a pipe, rod or the like elongated member

Info

Publication number: US3133469A
Application number: US85140A
Authority: US
Inventors: Ljungberg Sten Herman
Original assignee: Nitroglycerin AB
Current assignee: Nitroglycerin AB
Priority date: 1960-01-29
Filing date: 1961-01-26
Publication date: 1964-05-19
Anticipated expiration: 1981-05-19
Also published as: ES264438A1; CH380621A; DE1155045B; GB972073A; BE599599A

Description

May 19, '1964 s. H. LJUNGBERG 3, 33, 6

DEVICE FOR AXIAL DISPLACEMENT OF A PIPE, VROD OR THE LIKE ELONGATED MEMBER Filed Jan. 26. 1961 3 Sheets-Sheet l INVENTOR STEN HERMAN LJUNGBERG BY jawfswfK ATT ORNEY M y 19, 1964 s. H. LJUNTGBERLGE 3,133,469

DEVICE FOR AXIAL DISPILAGEMENE QE'A' PIPE, ROD OR THE LIKE EILONGATED: MEMBER Filed Jan. 26. 1961 s Sheets-Sheet 2 INVENTOR STEN HERMAN LJUNGBERG ATTORNEY Y WW May 19. 1964 5.1-1. LJUNGBERG 3,133,469

DEVICE FOR AXIAL DISPLACEMENT OF A PIPE, ROD.

OR THE LIKE ELONGATED MEMBER Filed Jan. 26. 1961 5 Sheets-Sheet 3 Fig. l.

ENE

Ill

ill

lNVENTOR STEN HERMAN LJUNGBERG ATTORNEY United States Patent Ofiice I 3,133,469 Patented May- 19, 1964 3,133,469 DEVICE FOR AXIAL DISPLACEMENT OF A PIPE, ROD OR THE LIKE ELONGATED MEMBER Sten Herman Ljungbcrg, Stockholm, Sweden, assignor to Nitroglycerin Aktiebolag, Gyttorp, Sweden, a corporation of Sweden Filed Jan. 26, 1961, Ser. No. 85,149 Claims priority, application Sweden Jan. 29, 1260 7 Claims. (Cl. 8620) This invention relates to a device for axial displacement of a pipe, a rod or the like elongated member.

More particularly this invention relates to a device for axial displacement of a pipe, a rod or the like elongated member in connection with the loading of bore-holes with explosive. The invention has primarily been brought up in connection with. charging bore-holes with explosives according "to a system disclosed in the co-pending patent application Serial No. 711,417, filed January 27, 1958, now Patent 13,040,615, by Carl H. Johansson and Sten H. Ljungberg, according to which disclosure the explosives are intro duced into the bore-hole through a pipe or a hose by means of a pressure medium as is more detailed described 'in the specification of the patent application referred to. 'As the bore-holes often have a great length, such as 10 metres and more, the handling of the pipes or hoses often becomes inconvenient. It is one main object of the invention to provide a device which permits the pipe, hose or similar member to be moved along with no need to resort to manpower, whereby the charging procedure is highly simplified, while at the same the charge is more uniform and the borehole is filled completely with the explosive.

Further objects and advantages of the invention will become apparent from the following description, considered in connection with the accompanying drawings which form part of the specification and of which:

FIG. 1 is a partly sectional elevation. of an apparatus for moving a pipe or a hose in connection with charging bore-holes in rocks with explosives; various parts of the figure being reproduced on different scales for clarity.

FIG. 2 shows a portion of the apparatus, partly in section parallel to the plane of the drawing according to FIG. 1, and on a larger scale.

FIG. 3 is a perspective view of a detail of FIG. 2.

FIG. 4 is a longitudinal sectional view of a modified embodiment of the invention. Referring to FIG. 1 reference numeral 10 denotes a bore-hole formed in the roof 12 of a drift or chamber in a rock. This example of the position of the hole has been chosen because it makes especially heavy demands upon the explosive charging operation. For securing the apparatus according to the invention a jack leg known per se is used, which is composed of two mutually axially displaceable parts 14-, 16 which are brought to rigid engagement with the roof 12 and fioor 2!), respectively, of the drift under the action of a pressure medium supplied through a conduit 18 and by way of a valve 19.

The apparatus shown in FIGS. 1 to 3 comprises an upper and a lower clamping member generally designated 22 and 24, respectively, which are constructed essentially alike and in accordance with the section shown in FIG. 2.

dium in the apparatus.

Thus each clamping member is provided with a container 26 in the form of an annular hose of rubber, plastic or some other resilient material. Between said hose and the pipe 28 to be moved along axially in the bore-hole 10 there is disposed a sleeve 38 serving as a wear lining, which sleeve may be made of plastic, rubber or the like and which is provided with slits 32 in front of the hose. The hose 26 is inserted into an annulus 34, which opens inwards, and between which. and a plate 36 the sleeve 30 is secured by a flange portion 38. When a pressure medium is supplied to the annular hose 26 through a mouthpiece 460, the hose expands and forces the sleeve 30 into engagement with the pipe 28 under such a pressure that the pipe is retained by the friction force simultaneously occurring.

The casing of the upper clamping member 22 is passed over the upper part 16 of the jack leg by means of a mufflike portion 42 and is secured to said part on the desired level by means of a bolt joint 44. This portion further carries a plate 46 towhich the two housings 48 of two actuators are rigidly secured. The one housing 48 may also be secured, by means of a clamp 50 and a bolt joint 52, to the upper part 16 of the jack leg. The casing of lower clamping member 24 is rigidly secured, by means of bolt joints 54, to piston rods 56 and pistons 58 axially movable in their respective actuator housings 48. Hence, the clamping member 24 is axially movable together with the pistons 58 in relation to the upper stationary clamping member 22.

A pressure medium, being a liquid or agas, primarily compressed air, is supplied to the apparatus from a pressure source through a conduit 60 wherein a valve 62 may be mounted. The conduit 60 has an extension 64 opening into the body 66 of a spool valve wherein aspool 68 is axially shiftable. From the valve body 66 a conduit 70 extends. leading to the annular hose 26 of the upper clamping member 22 by way of a

branch

72, 73 wherein a valve member 74 is disposed. Another branch 76 together with an extension 78 communicates with the top ends of the two actuator housings 48. A further conduit 80 connected to the valve body 66 divides into two branches, one of which 82, 83 passing through the valve member 74 and connecting to a flexible hose 84 which is extended to the hose 26 in the lower clamping member 24 by way of a conduit 36. The other branch 94 of the conduit 86 and its extension 92 terminates at the lower ends of the two actuator housings 48. The valve spool 68 has two lands 4, 96 which control the flow of pressure me- Thus in the position shown in FIG. 1 the supply conduit 64 for the pressure medium communicates with the conduit 70 so that the two top portions of the actuator housings 48 receive pressure medium via the

conduits

76 and 78, respectively. Further the valve member 74 is set in such a way that the pressure medium passes through the

conduit

72, 73 to the annular hose 26 of the upper clamping member 22. At the same time the bottom ends of the actuator housings 48 communicate, by way of

conduits

90, 82, 80, with an exhaust 98 in the valve body 66, said ends thus being free from pressure. By reversing the valve spool 68 to its opposite limit position the bottom ends of the actuator housings. 48 are placed under pressure while their top ends become free from pressure by communication being established with an exhaust 100 in the valve body 66.

The spool 68 is automatically operated by means of two limit valves 102, 104 accommodating spring actuated

valve plungers

106 and 108, respectively. The valve 102 is rigidly secured, by means of a bracket 118, to the one actuator housing 48 and thus to the stationary upper clamping member 22. The valve plunger 106 cooperates with an abutment arm 112 on the lower clamping member 24. The other valve 184 is rigidly secured, by means of a bracket 114, to the lower part 14 of the jack leg, and the valve plunger 108 co-operates with an abutment 116, likewise disposed on the clamping member 24.

From the conduit 64 a conduit 118 issues leading to valve 102 by one branch 120 and to valve 104 by another branch 122. A conduit 124 connects the valve 102 with the right-hand end, as viewed in FIG. 1, of the valve body 66 where the valve spool 68 has an end flange 126. From the valve 104 a conduit 128 issues to the left-hand end of the valve body 66 where the valve spool has an end flange 132. The two end portions of the valve body have bleed holes 99 and 127, respectively, through which the

conduit

124 or 128 inoperative at the time is made free from pressure by the pressure medium (air) escaping to the atmosphere.

A branch 129 from the conduit 64 is connected to the conduit 83 by way of a three-Way valve 130. In the conduit 129 a pressure reducing valve 131 is mounted. Thus, while by-passing the valve member 74 pressure medium may be directed through the conduit 129 and the three-way valve 130 to the lower clamping member 24. In the conduit 73 a shut-off valve 133 may be mounted for disconnecting the upper clamping member 22.

The device operates in the following way.

With reference to FIG. 1 it is assumed that the lower clamping member 24 has just been moved to its upper dead centre. The valve plunger 106 has been engaged by the abutment arm 112 so that the valve has opened, whereupon pressure medium is conducted by Way of

conduits

118, 120, 124 to the right-hand end of the valve body 66 where it affects the flange 126. Therefore the spool 68 has been brought to its left-hand limit position. This causes pressure medium to pass through conduit 64, valve body 66,

conduits

70, 76 and 78 to the top ends of the two actuator housings 48. Thus the top side of the pistons 58 is exposed to the action of the pressure medium and the lower clamping member 24 will therefore be brought downwards. According to FIG. 1 the valve 74 has been manually adjusted in such a way that the pressure medium also passes through

conduits

72 and 73 and the open valve 133 to the hose 26 of the upper clamping member 22. In other Words, the pipe 28 is retained in its axial position by the stationary upper clamping member 22. During the downward movement of the clamping member 24,

conduits

92, 90, 80 are free from pressure on account of the fact that they communicate, as previously mentioned, with the exhaust 98 in the valve body 66. Because of the setting of the valve 74 also the hose 26 of the lower clamping member 24 is free from pressure, for which reason this clamping member may be unimpededly displaced in relationship to the pipe 28. The valve 130 is set for communication between

conduits

83 and 84, and the conduit 129 is thus disconnected.

At the end of its downward movement the clamping member 24 strikes the movable part 108 of the valve 104 with its abutment 116. The valve 102 has previously closed by the abutment arm 112 leaving its valve plunger 106. In consequence hereof pressure medium will now be supplied, via

conduits

118, 122, 128, to the left-hand end of the valve body 66 where it affects the flange 132, for which reason the spool 68 reverses to its right-hand limit position. Further the conduit 70 is connected to the exhaust 100 so that the

conduits

76 and 78 and thus from below by the pressure medium which moves the pistons and the clamping member 24 upwards. The valve 74 retains the same setting from which follows that the upper clamping member 22 becomes free from pressure simultaneously with the pressure medium supply to the actuators being reversed, while the lower clamping member 24 becomes operative for clamping the pipe 28. The pipe is thus brought along upwards by the lower clamping member 24. In this way the clamping member 24 will automatically reciprocate up and down and bring along the pipe 28 during its upward movement, said pipe on the other hand being locked by the upper stationary clamping member 22 during the downward movement.

After the pipe 28, which can comprise a hose of plastic, has been raised upwards in this manner to the desired depth of the bore-hole 10, charging the hole with explosive begins, the explosive suitably being in the form of cartridges which are fed by a pressure medium through the interior of the pipe 28, for instance, in accordance with the co-pending patent application Serial No. 711,417 referred to hereinbefore. According as the filling proceeds the pipe 28 is to be brought back downwards. As the pipe 28 in the embodiment will move downwards by gravity, the friction force against the pipe may be adjusted in such a way so that slipping occurs at a desired speed. However, it is to advantage to move the pipe inwards step by step in order to bring about a stamping of the explosive. This may be provided by resetting the valve 130 so that the lower clamping member 24 receives pressure medium through the conduit 129 under a pressure corresponding to the setting of the reducing valve 131. Further valve 133 is shut off. This means that while the movable clamping member 24 is brought up and down as before under control of the reversing valve spool 68, only the clamping member 24 is operative to lock the pipe 28. As the clamping member 24 is continuously under pressure it seizes the pipe in both directions of movement. However, the clamping power is limited thanks to the pressure reducing valve 131 so that the pipe 28 slips in relationship to the clamping member 24 during the upward movement. In this way a stamping of the explosive or cartridges of explosive, respectively, is attained according as they leave the pipe 28. This stamping may be varied by adjusting the valve 131 to various pressures so that slipping occurs between the pipe and the clamping member 24 at a corresponding counter-pressure of the explosive.

If, on the other hand, the pipe 28 is to brought downwards quickly, e.g. after the hole 10 has been filled with explosive to the intended depth, the valve 133 is opened. The valve member 74 is shifted 90 clockwise and the three-way valve 130 is shifted in a way to reestablish communication between the

conduits

83 and 84. At the same time as the top ends of the actuator housings 48 are supplied with pressure medium for performing a downward movement of the clamping member 24, the

also the top ends of the actuators become pressure-free.

latter retains and brings with it the pipe 28. As the conduit 73 communicates with conduits 82, and is free from pressure, the upper clamping member 22 is inoperative. When later the spool 68 reverses and the lower clamping member 24 performs its upward stroke, the hose 26 of this clamping member has been made inoperative by

conduits

86, 84, 83, 72, 70 being connected to the exhaust 100, while the upper clamping member 22 locks the pipes 28 in its position by the member receiving pressure medium through

conduits

64, 80, 82 and 73. In this case also the pipe 28 is given a stepwise movement in the outward direction, but in a faster tempo than when the charging operation was in progress.

As is readily understood from the preceding description of the embodiment shown in FIGS. 1 to 3, the apparatus is capable of operating with the clamping member 22 out of operation and the clamping member 24 continuously subjected to pressure in both directions of displacement of the pipe 28. The embodiment shown in FIG. 4 represents'an apparatus intended solely for this manner of operation. The apparatus is thus provided with a sole clamping member 24 to which pressure medium is supplied through flexible conduits 86 and the pressure reducing valve 131 in the same manner as in the embodiment described hereinbefore. The clamping member is rigidly secured to the piston rod 56 of the piston 58 which is reciprocable within the housing 48 of the actuator. This housing is connected with a frame tube 134 which on its one end supports av blister or container 136 having a wall made of a resilient material such as rubber. To this container pressure fluid is fed through a conduit 138 and causes said container to expand so as to engage the Wall of the bore-hole and thereby to retain the apparatus firmly in its position. The pressure medium is supplied to the clamping member 24 and to the retaining member 136 from

conduit

140 or 142, respectively, through a valve housing 144. The pressures act during the charging operation constantly on both members and are determined in relationship to one another so as to cause the member 136 to retain the apparatus firmly in its operative position and the clamping member to allow a sliding or skidding movement of the pipe 28 in one of its directions of movement. Pressure medium is further supplied alternately to one or the other side of the piston 58 to produce the reciprocating movement of said piston and of the clamping member 24 by means of valve 144 which may be of the same kind as the valve 66 so as to cause the reversal of the movement to be produced automatically.

In the use of the device shown in FIG. 4, the bore-hole is disposed in a downward direction and the elongated member or pipe 28 is threaded through the device and is manually fed into the bore-hole where it falls by gravity until it reaches the bottom thereof. The device is then inserted in the top portion of the bore-hole and fluid pressure is applied to cause the blister 136 to expand and engage the side walls of the bore-hole and firmly anchor the device. A cartridge or charge of exposive is introduced into the bore-hole through the pipe 28 after which fluid pressure will be directed into the lower portion of the housing 48 and cause the piston 58 to move upwardly. Simultaneously, pressure is introduced into the clamping member 24 under the influence of reducing valve 131 and such clamping member will apply a predetermined pressure on the pipe 28. Since the clamping member is attached to the piston rod 56, upward movement of the piston 58 will cause the pipe 28 to be withdrawn a distance corresponding to the stroke of the piston and greater than the length of the explosive cartridge so that the cartridge is discharged from the pipe.

When the piston reaches its upper extremity, the fluid pressure within the housing will be reversed automatically and the piston will be moved downwardly. The pipe 28 likewise will be moved downwardly until it engages the cartridge of explosive whereupon further downward movement of the piston will cause the pipe to exert a downward pressure on the cartridge and pack the cartridge in the bore-hole. When the cartridge has been firmly packed, the resistance to further movement of the pipe will overcome the pressure applied by the clamping member 24 and such clamping member will slide relative to the pipe. During the downward movement of the piston, another cartridge of explosive is passed down the pipe either by force or by gravity so that when the piston reaches the bottom of its stroke, the fluid pressure within the housing again is reversed automatically and the process is repeated.

When the desired explosive charge has been packed into the bore-hole, the pressure is relieved on the device and the device and pipe are withdrawn from the bore-hole.

While two more or less specific embodiments of the invention have been shown and described, it is to be understood that this is for purpose of illustration only, and

'6 that the invention is notto be limited thereby, but its scope is to be determined by the appended claims.

What I claim is:

1. A device for axial displacement of an elongated member for charging bore-holes with explosives by repetitious movement of relatively small units of explosives into the boreholes comprising a clamping member provided with a container having a wall of resilient material and formed to seize said elongated. member, an actuator comprising a housing and a piston disposed within said housing, said housing and said piston being displaceable relative to one another by reciprocative motion of one of them, means to connect said clamping member with the movable part of said actuator, a source of pressure medium, and automatic means to connect said container and alternately one or the other side of the movable part of said actuator to said source of pressure medium to produce the displacement of said elongated member.

2. A device for axial displacement of an elongated member as claimed in claim 1 comprising means to subject the clamping member continuously to pressure and thereby to cause said clamping member to carry along said elongated member during the reciprocating movement of the movable part of the actuator, said clamping member being devised so as to allow said elongated member to slide relatively to said clamping member during its motion in one direction meeting a resistance surpassing the resistance during its motion in the opposite direction.

3. A device for axial displacement of an elongated member comprising a clamping member having a container with a resilient wall formed to receive the elongated member, an actuator comprising a housing and a piston disposed within said housing, said housing and said piston being relatively displaceable by reciprocative motion of one of them, means connecting said clamping member with the movable part of said actuator, a source of pressure medium, means connecting said clamping member continuously with said source of pressure medium, means connecting said container and alternately one or the other side of the movable part of said actuator to said source of pressure medium to produce the displacement of said elongated member, said clamping member being so constructed and arranged as to permit the elongated member to slide relatively to the clamping member during motion of the latter when said elongated member encounters a predetermined resistance to motion in the direction of movement, and means responsive to the position of the clamping member to automatically alternate the connection of the container to the source of pressure medium.

4. A device for axial displacement of an elongated member as defined in claim 1, said housing being supported rigidly with respect to a borehole, said supporting means comprising a container having expandable means engageable with the walls of the borehole, and means to supply said pressure medium to said expandable means.

5. A device for axial displacement of an elongated member for charging bore-holes with explosives comprising an actuator including a housing, a piston rod mounted within said housing and extending outwardly thereof, a piston located within said housing and mounted on said piston rod, one of said piston and said housing being movable and the other being fixed, a clamping member mounted on the movable portion of said actuator, a source of fluid pressure, means for continuously connecting said source of fluid pressure with said clamping member, means automatically connecting said source of fluid pressure with said housing on alternate sides of the movable portion of said actuator to produce the displacement of said elongated member, and pressure reducing means disposed between said source of fluid pressure and said clamping member, whereby the elongated member will slide relative to said clamping member when the elongated member encounters a predetermined resistance in the direction of movement.

'6. A device for axial displacement of an elongated member comprising an actuator including at least one housing, piston rod means extending into said housing, piston means Connected to said piston rod means within said housing, said housing and said piston rod means being movable relative to each other, clamping means carried by the movable portion of said actuator, means for continuously connecting said clamping means to a source of pressure, pressure reducing means disposed between the source of pressure and said clamping means, and means automatically connecting the source of pressure with said actuator on opposite sides of the movable portion thereof, whereby the elongated member will slide References Cited in the file of this patent UNITED STATES PATENTS 1,586,923 Townsend June 1, 1926 1,853,856 Gattrell Apr. 12, 1932 2,748,870 Basham et al. June 5, 1956 2,830,788 Bentley et a1. Apr. 15, 1958 2,944,403 Smith July 12, 1960

Claims

1. A DEVICE FOR AXIAL DISPLACEMENT OF AN ELONGATED MEMBER FOR CHARGING BORE-HOLES WITH EXPLOSIVES BY REPETITIOUS MOVEMENT OF RELATIVELY SMALL UNITS OF EXPLOSIVES INTO THE BOREHOLES COMPRISING A CLAMPING MEMBER PROVIDED WITH A CONTAINER HAVING A WALL OF RESILIENT MATERIAL AND FORMED TO SEIZE SAID ELONGATED MEMBER, AN ACTUATOR COMPRISING A HOUSING AND A PISTON DISPOSED WITHIN SAID HOUSING, SAID HOUSING AND SAID PISTON DISPLACEABLE RELATIVE TO ONE ANOTHER BY RECIPROCATIVE MOTION OF ONE OF THEM, MEANS TO CONNECT SAID CLAMPING MEMBER WITH THE MOVABLE PART OF SAID ACTUATOR, A SOURCE OF PRESSURE MEDIUM, AND AUTOMATIC MEANS TO CONNECT SAID CONTAINER AND ALTERNATELY ONE OR THE OTHER SIDE OF THE MOVABLE PART OF SAID ACTUATOR TO SAID SOURCE OF PRESSURE MEDIUM TO PRODUCE THE DISPLACEMENT OF SAID ELONGATED MEMBER.