US2083737A - Blasting method and apparatus - Google Patents

Description

June 15, 1937. w, NOBLE 2,083,737

BLASTING METHOD AND APPARATUS Filed June 1, 1935 2 Sheets-Sheet 1 w'nmuh ML June 15, 1937. w NQBVLE 2,083,737

BLASTING METHOD AND APPARATUS Filed June 1, 1935 2 Sheets-Sheet 2 51 My :75 60 as 64 f I V/ A 65 66 7 7 73 (72% 60/ 63 142294971534 ;9- ZMMWZMZZQ z JAM Am Patented June 15, 1937 UNITED STATES BLASTING METHOD AND APPARATUS Application June 1, 1935, Serial No. 24,570

18 Claims.

My invention relates to material breaking methods and apparatus, and more particularly to improvements in methods of and apparatus for controlling the release of the blasting charge ,from blasting cartridges of the type in which high pressure gas is employed as the blasting medium. A very useful method of breaking down or fracturing material employs in the place of explosives a shell disposable in a hole in the material to be 1, fractured and comprising a. chamber in which a acting on the larger pressure area is released, to

open the charge release valve means and hold it ,open notwithstanding the sudden and very great reduction in storage chamber pressure which im- ,mediately ensues. The smaller area has communication with the storage chamber which per- ,mits ready passage of chamber pressure to the area, but precludes reverse flow when the parts are in charging position, and provides for only arestricted bleeding upon charge release, and

. thereby prevents a sudden drop in chamber pressure from also equally lowering the pressure on the smaller area and thereby permitting the less rapidly dropping pressure on the larger area momentarily reclosing the charge release valve means, with a resultant charge release in steps.

. .The larger area. is provided upon an element which constitutes a movable wall of a control chamber, and pressure on its way to the storage chamber passes through the control chamber, but

, is precluded from reverse flow from the storage chamber to the control chamber. Release of the charge is effected by discontinuing pressure sup- Iplyto the control chamber and venting the latter. Venting means has been provided of such 5 .a nature that it may be arranged near but outside of the face of the material to bebroken in which the shell is positioned, but such an arrangement, as so far constructed, is permanently attached to the short tubular connection .50 which is fixed to the shell in communication with the control chamber in the latter. Were it possible to effect automatic disconnection of a control device from this short tubular connection at will, it wouldautomatically follow that damage to the s'gtubing would be diminished, and the full cross sectional area of the tubular connection would inevitably be available for rapid reduction of control chamber pressure. It will hereinafter be noted that my invention accomplishes this result.

An object of this invention is to provide an improved blasting apparatus. A second object is to provide an improved material breaking method. Another object is to provide an improved apparatus for efiecting charge release from a blasting cartridge in which a substantial quantity of highly compressed gas is imprisoned. Another object of the invention is to provide an improved means for both efiecting the release of the charge from a high-.pressure-gas charged cartridge, and for disconnecting the cartridge .from a supply line which leads thereto. Still another object of the invention is to provide an improved device for efiecting the automatic release of the charge from a gas-charged cartridge upon the attainment of the desired pressure in such cartridge, and incorporating in said apparatus means whereby the discharge pressure may be selected at will. Other objects and advantages of the invention will be hereinafter more fully disclosed.

In the accompanying drawings there are shown for purposes of illustration two forms which the invention may assume in practice, together with a detail modification.

In the drawings,

Fig. 1 is a somewhat diagrammatic view showing the association of a blasting cartridge and the improved controlmeans therefor, in working relation to a coal-seam.

Fig. 2 is a central longitudinal section through the controlling means shown in Fig. 1.

Figs. 3, 4 and 5 are transverse sections respectively on planes corresponding to the section lines 3-3,. 4 4, and 5--5 of Fig. 2.

Fig. 6 .is a detail of a modified sealing and connecting arrangement.

Fig. 7 is a sectional view, similar to Fig. 2, showing a modified embodiment.

Fig. 8 is a detail section on a plane corresponding to line 8-8 of Fig. 7.

Fig. 9 is a transverse section on a plane corresponding to the line 9-9 of Fig. '7, and

Fig. 10 is a longitudinal sectional view of the cartridge disclosed in a coal seam in Fig. 1.

Referring to the drawings, it will be observed i that a blasting cartridge or shell I, which may advantageously be of the construction shown in Fig. 10 and in the application of one Frank H. Armstrong, Serial No. 18,579, filed April 27, 1935, is disposed in a bore 2 formed in the material to be broken down, herein coal, 3, in a position near the top of the coal, which has been undercut at i. ressure fluid is supplied to the cartridge l by way of a connection or pig-tail 5, hrough the improved control mechanism generally designated 6, from a supply line l, which may be connected to a suitable receiver or, more commonly, to high pressure compressor which may be arranged at a suitable distance from the cartridge and the working face.

The mode of operation of the system illustrated, is to con-duct the pressure, as the same is pumped up in the compressor (not shown), through the control mechanism 6 to the control chamber in the shell, and thence to the charge receiving chamber of the latter, and upon the at; tainment of a predetermined desired pressure, governed by the adjustment of the apparatus 6 itself, to effect an automatic disconnection of the apparatus 6 from the cartridge, by disconnection from the relatively short lead or pigtail 5, and thereby vent the control chamber of the cartridge so that the cartridge will be discharged.

Referring toFig. 2, it will be noted that the connection I is held by any suitable nut device 8 in sealing relation with a perforated abutment member El, arranged at one end of a chamber It in a housing H. The other end of the housing is connectible with the tubular connection or pig-tail 5 by releasable means hereinafter described. Within the chamber til is pressure responsive means, operative on attainment of the desired pressure to provide the force and motion necessary to effect release of the pig-tail holding means Herein this takes the form of an initially flattened tube, but widely varied forms may be assumed. One end of a centrally partially flattened metallic tubular member 52 is arranged in sealing engagement with the threaded member 9, while the other end abuts against a perforated washer 53. A port Hi through an alined flexible sealing washer l5 connects the bore of the tube, through the bore of the washer it, with the bore of the flexible lead 5. A bore ll opens radially out of the chamber I0 and forms a guideway for a rounded-ended plunger element 88. The lower end of the plunger element in Fig. 2 rests upon the flattened portion of the tubular element l2. A strong lever 2| is mounted, with some play, upon a heavy pivot pin 22 at one end, and its opposite end extends into position for engagement with a pivotally mounted latch element 23. The latter is swingable upon a pivot pin 24 and is, when free, held in its dotted position (released position) by a spring 25.

'The latch member has a manual controlling portion 26 and a threaded face-portion 27 which is adapted to engage with threads 28 formed upon the tubular flexible lead or pig-tail 5. The central portion of the body H may be formed with projecting threads 30 and the back of the lever ii is threaded at Si so that these parts may coact with threads upon an internally threaded member 32.

The function of the member 32 is to provide suflicient resistance to outward swing of the lever 2! to preclude release of the latch 23 until the desired pressure is attained. It will be noted that the member 32 may be adjusted along the threaded periphery of the threaded member H, and that as it approaches the pivot pin 22 the pressure necessary to expand it sufiiciently to release the latch will diminish, while as the member 32 is moved toward the free end of the lever 2| a greater pressure will be requisite to expand it sufficiently to allow disengagement between the free end of the lever and the latch 23. With a construction in which the ratio of the full length of the lever 2! to the distance between the locus of the ring 32 and the pivot 22 is relatively great, so that the movement of the free end of the lever relative to the latch will be comparatively large compared with the necessary increase in diameter of the member 32, the member 32 may be made as a continuous, suitable, spring steel or other relatively elastic metal annulus. Because of the relatively small extensibility of metals before their yield point is reached, however, more satisfactory results will be obtained in general through the use of an elastic metallic ring split at one portion with its ends adjacent the split pressed together by a powerful spring. Other suitable constructions would include a ring split at diametrically opposite points and spring-held together, or a hinged ring, or a multi-part ring with a heavy spring surrounding its periphery; and various other arrangements whereby the necessary capacity for yielding, coupled with the necessary resistance to yielding, may be obtained, will readily suggest themselves to those skilled in the art. Moreover, a solid ring of suitable size and material, replaceable after each charge-release, may be used as a rupturable control element, if that be desired, as the feature of automatic release of the pig-tail at the desired pressure within the control device is independent of the particular limit determining means.

Before describing the mode of operation of the apparatus so far mentioned, it is desired to call attention to the fact that it is possible, as shown in Fig. 6, to provide a conical seat 42 on the housing member i l, employ a washer 43 adjacent the flared end id of the connection, and use an externally threaded tubular member 45 surrounding the lead 5 and having a polygonal turning portion 38 and eifect an adjustment relative to the threads 27 after the parts are brought into assembled relation, thereby to effect a very positive and effective seal, and also to facilitate the latching operation.

The mode of operation of the device heretofore described may now be readily understood. It will be evident that with the parts arranged as shown in Figs. 1 and 2, if a compressor whose discharge is connected with the pipe I be set in operation, fluid will flow through the connection l, through the member 9 and through the passage in the tubular member l2, through the passage M, and through the lead 5 or pig-tail into the cartridge I, where it will ultimately enter the charge receiving chamber in the latter and be there entrapped. Depending upon the position of the member 32 longitudinally of the member l l and upon its construction, it will be evident that, before the increasing pressure therein will be enabled to round out the tube l2, and thereby press the member is outwardly suificiently so that the free end of lever 2! may release the latch 23, a wide range of pressures may be made necessary. When the desired pressure for which the apparatus is set is attained, the inner edge or corner of the free end of the lever M will clear the point 23 of the latch the latter, by the spring 25 and also by the wedge action of the threads 28, will be snapped into released position, and the housing M will be disconnected from the lead 5.

Thereupon the lead 5 or pig-tail will be vented to atmosphere and will itself vent the control chamber of the cartridge I and cause the discharge of the charge from the cartridge. A new, deformable element 52 may be used each time if desired, or this element may be appropriately re- .deformed to its initial condition and re-used.

With other constructions of this member, the step of re-deforming may be eliminated.

Figs. 7, 8 and 9 illustrate another possible construction. Here it will be noted that the supply connection 1, adjustable holding means therefor 8, abutment 9, fiuid-expansible member i2, releasable connection 5, and latch 23 are all substantially the same as in the first illustrative embodiment. The lever 25 is here mounted upon the eccentric pin portion 50 of a short, transverselyextending, rotatable shaft which is provided with worm teeth 52 near its outer end, and which is rotatable by a vertical worm-like member 53 having a squared head 55 by which the same may be turned. The rear end of the lever 2 I is slotted as at 55, and its rear end may be closed by a transverse pin, if desired. The member 32 is made up of upper and lower pivotally connected halves 32 and 32 and at the side thereof opposite the pivot 5'5 there is an appropriate heavy spring 58 for clamping the halves 32 and 32 with the threads thereon in tight engagement with the member ii. In this construction the outer surface of the lever 2i is not threaded, so that the pin iiil may move the lever longitudinally without dif culty. The pin 59 may be in bottom position, or in rearward position, when it is desired to connect the control device to a pig-tail, and then moved through 90 or 180,

' counterclockwise, by the member 53 and threads 52to locate the latch. 23 very tightly in engagement with the threaded end of the pig-tail 5. Further description of this structure is unnecessary, in view of what has previously been said.

It will be evident from the description so far given that I have provided an improved controlling apparatus for a gas charged shell, that this apparatus is simple, not expensive, and provides for discharge at different predetermined pressures depending upon where the member 32 is set with respect to the length of the casing II and the construction of said member,'the pressure necessary to effect flexing of the tube walls. to

' force the member !8 out and disengage the latch increasing as the member 32 is moved toward the right hand end of the casing member H and with the relative inflexibility of member 32. It will be noted, moreover, that when the mechanism 6 is disconnected from the lead, the latter is not only opened to atmosphere for the full bore area, but alsofreed from the main supply line, and accordingly should there be any marked movement of the shell away from its initial position, there will be no tendency to deform the main supply connection 1.

In Fig. 10, there is disclosed in detail the form of cartridge which is described and claimed in the aforementioned application filed by Frank H. Armstrong. This cartridge comprises a tubular casing 5t having a chamber 6| for receiving a charge of high pressure gas, as for example highly compressed air; and threaded within the inner end of this casing is a discharge cap 62 having an axial discharge orifice 63 communicating with the pressure chamber BI and connected by a series of generally radial, outwardly inclined discharge ports 64 with the shell exterior. Threadedly secured within the outer end of the casing 613 is a control cap 85 having a control chamber 66 containing a reciprocable control piston 61.

The piston rod 68 of this piston extends inwardly within the pressure chamber BI and has fixed to its inner extremity a pressure release valve 69 adapted to seat at H on the inner end of the discharge cap to prevent communication of the discharge orifice 63 with the pressure chamber. Positioned between the'inner end of the control cap 65 and an internal annular shoulder 12 formed within the casing Bil, is a heavy steel plate or disc 13 to which is secured a hat leather Hi, surrounding and adapted to seat on the exterior surface of the valve rod 68, which passes therethrough. The piston 61 consists of a steel plunger 15 carrying a cup leather 16 held in position by a keeper 'll threaded on the valve rod 68. Threaded at 18 within the control cap 65 is the pig-tail 5 adapted to communicate with a suitable source of high pressure gas or to be vented; and this pig-tail is connected through an axial passage 80 with the control chamber 66 at the outer side of the control piston. A suitable check valve 8| with check spring 82 is provided in the plunger 15 as means for permitting the flow of high pressure gas from the control chamber 66 at the outer side of the control piston, through an axial passage 83 in the valve rod and communicating radial passages 84, into the main chamber 6| of the shell, but preventing flow in the reverse direction. A restricted radial passage 85 in the rod 68 extends from the axial passage 83 to the exterior of the valve rod, and is located at such a point that its outer end, when the piston and valve assembly is in the position shown in Fig. 10, communicates with the main chamber BI, and when the piston and valve assembly is moved rearwardly, communicates with the space between the inner side of the control piston and the disc 13, thereby connecting this space with the chamber El, and so to atmosphere, noting that the valve 69 is then open.

The mode of operation of this cartridge is generally described at the beginning of this specification and such description need not be repeated at this point as the cartridge per se forms no part of the present invention.

While there are in this application specifically described two forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pressure in which to a predetermined amount below cartridge pressure effects charge release, and means for connecting said chamber with a source of charging pressure including a device operative automatically upon attainment of a predetermined charge pressure in the cartridge to vent to the atmosphere the charge in the control chamber by disconnecting the cartridge from its source of supply, whereby the release valve of the cartridge will be actuated to efiect release of the blasting charge.

2. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pressure in which to a predetermined amount below 5 cartridge pressure effects charge release, and

means for connecting said chamber with a source of charging pressure including a device operative automatically to effect disconnection of said cartridge and reduction of the pressure in said control chamber upon attainment of a predetermined pressure in said device, said device includ ing a releasable coupling and means operable by the charging pressure for actuating said releasable coupling.

3. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pressure in which to a predetermined amount below cartridge pressure effects charge release, and means for connecting said chamber with a source of charging pressure including a device through which the charge passes on its way into the cartridge and operative automatically to effect disconnection of said cartridge and reduction of the pressure in the control chamber upon attainment of a predetermined charge pressure, said device including a releasable connection, and charge pressure controlled means for preventing release operation'of said connection until subjected to a predetermined pressure.

4. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pres sure in which to a predetermined amount below cartridge pressure effects charge release, and means for connecting said chamber with a source of charging pressure including a device through which the charge passes on its way into the cartridge and operative automatically to effect disconnection of said cartridge and reduction of the pressure in the control chamber upon attainment of a predetermined pressure in said device, said device including a releasable coupling, and a charge pressure controlled clamp for restraining release operation of said coupling until subjected to a predetermined pressure.

5. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pressure: in which to a predetermined amount below cartridge pressure effects charge release, and means for connecting said chamber with a source of charging pressure including a device operative automatically to effect disconnection of said cartridge and reduction of the pressure in said control chamber upon attainment of any one of a series of selected predetermined charge pressures.

6. In combination, a blasting cartridge for containing a charge of gaseous medium at a blasting pressure, charge release means including a release valve and means for controlling the same including a control chamber through which said cartridge is charged and reduction of the pressure in which to a predetermined amount below cartridge pressure effects charge release,

and means for connecting said chamber with a source of charging pressure including a device operative automatically to effect disconnection of said cartridge and reduction of the pressure in said control chamber upon attainment of any one of a series of selected predetermined pressures in said device, said device including a releasable coupling, and charge pressure operated means for restraining actuation of said releasable coupling including an adjustable, yieldable restraining element.

7. In an apparatus of the character described, a member having provision for the flow therethrough of a cartridge charging medium and having therein a device responsive to the pressure flowing therethrough, a cartridge charging conduit, means for clamping the same to said member, and means for effecting release of said clamping means governed by said pressure responsive device.

6. In an apparatus of the character described, a member having provision for the flow therethrough of a cartridge charging medium and having therein a device responsive to the pressure flowing therethrough, a cartridge charging conduit, means for clamping the same to said member, and means for effecting release of said clamping means governed by said pressure responsive device and including a latch controlled by the latter.

9. In an apparatus of the character described, a member having a connection at one end to a source of cartridge charging pressure, at its other end a releasable connection to a cartridge charging line, and between said ends a conduit for connecting said lines, and means governed by the pressure in said conduit for effecting release of the latter connection.

10. In an apparatus of the character described, a member having a connection at one end to a source of cartridge charging pressure, at its other end a releasable connection to a cartridge charging line, and between said ends a conduit for connecting said lines, and means governed by the pressure in said conduit for effecting release of the latter connection including a connection holding device and a latch therefor movable in response to pressure rise in said conduit.

11. In apparatus of the character described, a charge feeding connection for a blasting car tridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including conduit gripping means, restraining means for said gripping means, and means directly responsive to the charge pressure for displacing said restraining means to automatically effect uncoupling of said conduit upon attainment of any one of a series of selected predetermined pressures in said de vice.

12. In apparatus of the character described, a charge feeding connection for a blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding movable conduit including a connection clamping device, and means responsive to the pressure in said coupling means for restraining said device against movement until subjected to a predetermined pressure whereupon it will effect release of said clamping device.

13. In apparatus of the character described, a charge feeding connection for a blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, means for holding said clamping device against movement to release said connection, and means responsive to the pressure in said coupling means for displacing said holding means to permit release movement of said clamping device.

14. In apparatus of the character described, a charge feeding connection for a blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, means for holding said clamping device against movement to release said connection, and means adjustable so as to be responsive to any one of a series of selected predetermined pressures in said coupling 7 means for displacing said holding means to permit release movement of said clamping device.

15. Apparatus of the character described com- 0 prising a charge feeding connection for a blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, a latch for holding said clamping device against connection releasing movement, and pressure responsive means for tripping said latch.

16. Apparatus of the character described comprising a charge feeding connection for a blast- 30 ing cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, a latch for holding said clamping device against connection releasing movement, and means responsive to pressure in said coupling means for tripping said latch.

17. Apparatus of the character described comprising a charge feeding connection for a blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, a latch for holding said clamping device against connection releasing movement, and means adjustable so as to be responsive to any one of a plurality of pressures in said coupling for tripping said latch.

18. Apparatus of the character described comprising a charge feeding connectionfora blasting cartridge, a conduit through which a charging medium flows, and means for coupling said conduit to said feeding connection including a movable connection clamping device, a latch for holding said clamping device against connection releasing movement, a lever pivotally connected to the coupling means and engaging said latch, and pressure responsive means for holding the lever in latch engaging position until the attainment of a predetermined pressure within said coupling means and then for moving the lever out of holding engagement with the clamping device.

WARREN NOBLE.

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