US1714024A - Collapsible wedge block - Google Patents

Collapsible wedge block Download PDF

Info

Publication number
US1714024A
US1714024A US197737A US19773727A US1714024A US 1714024 A US1714024 A US 1714024A US 197737 A US197737 A US 197737A US 19773727 A US19773727 A US 19773727A US 1714024 A US1714024 A US 1714024A
Authority
US
United States
Prior art keywords
block
face
blocks
faces
recess
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US197737A
Inventor
Helsing J Linus
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US197737A priority Critical patent/US1714024A/en
Application granted granted Critical
Publication of US1714024A publication Critical patent/US1714024A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/02Non-telescopic props
    • E21D15/06Non-telescopic props with parts joined by a lock, with or without slight axial adjustability
    • E21D15/12Non-telescopic props with parts joined by a lock, with or without slight axial adjustability with locking devices located near head or foot

Definitions

  • myinvention is to provide a collapsible wedge structure particularly adapted for use in. connection with mine )ro s.
  • my invention consists in the. construction, arrangement and combination of the various parts of my collapsible wedge, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out 1n my claims, and illustrated in the accompanying drawings, in which: ⁇ l
  • Figure 1 is a side elevation of a collapsible wedge embodying my ⁇ invention' installed in connection with a mine prop.
  • Figure 2 is a perspective view of the lower. block forming a part of my collapsible wedge structure.
  • Figure 3 is a perspective viewl of the lower block of a slightly modified form of my device.
  • Figure 4 is a vertical, sectional view through my collapsible wedge structure, embodying the modified form.-
  • Figure 5 is a perspective view of the operating screw used. with the modified form.
  • Figure 6 is a perspective .view of the small y adjustable wedgeuscd in the modified form.
  • Figure 7 is a verticah'sectional view of the wedge shown in Figure 6 taken on the line 7 7 of Figure 6.
  • Figure 8 is a horizontal, sectional view taken on the line 8-8 of Figure-7 and V Figure 9 is a perspective view of the rod used with my device.
  • a plate or blockor thelike indicated by the reference numeral 10 is placed on the mine floor.
  • My collapsible ywedgestructure com,- prising the blocks-12and 14 is supported on the block 10.
  • my lcollapsible wedge structure I place an ordinary propv16 in upright i position.
  • On the upper end ofthe may be placed a block or cap 12.
  • The. block 12 has a flat bottom and an inclined upper face20.
  • the face 2Oy is inclined from what I will for convenience call the rear facei12a of the block 12 downwardly and forwardly from the horizontal.
  • the front face of the groove 22'indicated at 22a is arranged in aplane at right angles toV 'the plane of the face 20.
  • f' sible wedge structure I will refer to 1t as it 1s
  • the groove 22 is deep enough toy wholly receive a heavy rod 24, preferably of steel.
  • I preferably f provide the block 14, having the upper face time for removal arrives.
  • the under-face of the block 14 indicated at 26 is beveled to correspond to the bevel of the face 2O and is provided with a longitudinal groove 28 of such depth as to receive somewhat less than half of the cylindrical rod 24.
  • the block 12 is placed on the base 10 in the proper location. I then partially lill the groove 22 with sand 30.
  • the sand 3() is filled to such a height as to support the rod 24 in position for projecting above the face 2O suiliciently to substantially and snugly fill the groove 28.
  • the block 14 is then placed in position where the groove 28 receives the rod 24.
  • the prop 16 is set on the block 14 and the cap 18 inserted snugly under the mine roof. If the roof sags any, it rests on the structure thus ciected and will be held against falling.
  • the prop After the prop has served its purpose, I drill out a portion of the sand 30. It will be understood that removable gates 30, held in place by guides 30h, are used to hold the sand in place at the ends of the groove 22 until the After aA portion of the sand 30 has been taken out in any convenient way, the block 12 may be tapped, whereupon the sand will drop, thus permitting the rod 24 to drop, whereupon the block 14 will slide down the face 2O and the supporting structure will be collapsed.
  • the blocks 12 and 14 are preferably of cast metal but may be of any suitable material.
  • I' use a block similar to the block 12 provided with the groove 34 similar to the groove ⁇ 22.
  • I provide an offset recess 36 extending toward the rear wall of the face 32L of the block 32.
  • a threaded hole 38 extends from the lower part of the recess 36 to the face 32a.
  • a screw 40 is threaded into the hole 38.
  • the screw 40 has the out-er head 40a, and at its inner end theV reduced neck 40'J and the enlarged head 40C.
  • I provide a small wedge or block 42, having the forward beveled face 42a.
  • rear, central part of the wedge 42 is a slot 44, which at its inner endhas an enlarged portion 46.
  • the slot 44 is intended to receive the reduced neck 4()ID of the screw 40 and the enlarged portion of the slot as at 46 receives the head 40c rotatably.
  • the block 14 is the saine as that shown in Figure 1.
  • the block 32 is placed on the base 1() ⁇ in the manner already described.
  • the screw 40 is rotated for forcing the small wedge 42 to its forward limit of movement, where it projects into the groove 34 In the lower as shown in Figure 4.
  • the rod 24 is then dropped into place in the groove 34 resting on the upper part of the beveled face 42a.
  • the block 14 ⁇ is ⁇ placed in position with less than halll of the rod 24 projecting into the groove 28. y
  • the prop may be installed in the usual way.
  • a pair of blocks having respectively a horizontal lower and a horizontal Y the prop has served its purpose
  • the screw 40 ⁇ inay be manipulated for pulling the upper face and having 4adjacent vbeveled faces inclined from the horizontal, said blocks having in their adjacent faces registering horizontal recesses, a cylindrical niember received in said recesses, and movable means for holding said cylindrical member in raised position, the recess in the lower block being of suliicient depth to permit the cylindrical member to drop downwardly thereinto when the movablemeans is removed from such recess.
  • a pair of blocks having respectively a lower horizontal and an upper horizont-al face and having adjacent'beveled faces, said blocks having in said beveled faces registering hori-A VZontal recesses, an adjustable round faced member adapted to be partially received in the respective recesses in said blocksymeans for holding said last-above described means in raised position adapted to be moved to position for permitting said adjustable ineinllo ber to drop into the recess in the lower block to thus permit the upper block to slide freely froln the lower block.
  • a pair of blocks having respectively lower and upper horizontal faces and having adjacent beveled faces, one block being superposed upon the other, said blocks having in their adjacent faces horizontal registering grooves, a cylindrical rod received in said grooves, the lower face ofthe groove in the lower block being arranged in a plane substantially at right angles to that of the beveled face of said block, and movable means for holding said cylindrical member in raised position with less than half of its bulk projected into the groove in the upper block.
  • a pair i of blocks having respectively lower and upper horizontal faces and having adjacent -beveled faces, one block being superposed rupon the other, said blocks having in their adjacent faces horizontal registering grooves, a cylindrical rod received in said grooves, the lower face of the groove in the lowerblock being arranged in a plane substantially at right angles to that of the beveled face of said block, and movable means for holding said cylindrical member' in raised position with less than half of its bulk projected into the groove in the upper block, said means comprising a slidable wedge, and means for adjusting said wedge to different positions for holding said movable member up or permitting it to drop intov the groove in the lower block.
  • a pair of blocks having coacting adjacentbeveled faces, said faces being provided with horizontal, transverse recesses adapted to register with each other when one of the blocks is superposed above the other, a member having a rounded upper face received in the recess in the lower block and capable of vertical up and down movement partially into and en# tirelyv out of the recess in the upper block, and means for controlling the up and down movementof said member.
  • a pair of blocks having coacting adjacent beveled faces, said faces being provided with transverse recesses adapted to register when one block is superposed upon the other, the recess in the lower block vhaving its lower side wall portion arranged in a plane substantially at right angles to that ofthe beveled ⁇ face of the lower block, a member adapted to travel into and out of the recess in thel lower block along said face in an up and down movement, and means for controlling such movement of said member.
  • a pair of blocks having respectively lower and upper horizontal faces and khaving adjacent beveled faces, said blocks having in their adjacent faces transverse horizontal recesses adapted to register when the upper block is superposedupon the other block, a substantially cylindrical member received in the recess in the lower block and adapted to be projected into the recessin the upper block, and movable'means :for holdingl said cylindrical member in raised positionpartially projected into the recess in the upper block adapted to be moved to position for permitting the cylindrical member to move downwardly bodily into the recess in the lower block.
  • a pair of blocks one of which is adapted to be superposed upon the other, the adjacent faces of the block having transverse recesses adapted to register when one block is thus superposed upon the other, a member adapted to travel up and down in said recesses having a recess in the upperblock having a facek of corresponding shape, and means for controlling the up and down movement of said member.
  • a pair of blocks having coacting adjacent beveled faces, said faces being provided with horizontal transverse recesses adapted to register with each other when one of the blocks is superposed on the other, a locking member having a rounded upper face receivedfin the recess in the lower block and capable of substantially lvertical up and down ymovement partially into and entirely out of the recess in the upper b'loclr, and means for support ing such member in raised position partially projected into the upper block and kadapted to be moved away from such supporting position.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Preliminary Treatment Of Fibers (AREA)

Description

Patented May Z1, 1929.
UNITED STATES J LINUS HELSING, oF DES MOINES, IOWA. i
COLLAPSIVBLE WEDGE B inoci.V l
. Appncation mea June 9, 1927.' suivaient. 197,737.
The purpose of myinvention is to provide a collapsible wedge structure particularly adapted for use in. connection with mine )ro s.
l It) is a special purposevof my invention to provide a pair of supporting members or blocks, onev or both of them having the form of a wedge and to providefmeaiis for connecting them against sliding movement with relation to each other, while they are used for supporting props, said means being suchk as to permit its movement to inoperative position, when it is desired to remove the props, for thus permitting one of said members to slide with relation to the other.
With these and other objects in view, my invention consists in the. construction, arrangement and combination of the various parts of my collapsible wedge, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out 1n my claims, and illustrated in the accompanying drawings, in which:` l
Figure 1 is a side elevation of a collapsible wedge embodying my `invention' installed in connection with a mine prop.
Figure 2 is a perspective view of the lower. block forming a part of my collapsible wedge structure.
Figure 3 is a perspective viewl of the lower block of a slightly modified form of my device.
Figure 4 is a vertical, sectional view through my collapsible wedge structure, embodying the modified form.-
Figure 5 is a perspective view of the operating screw used. with the modified form.
Figure 6 is a perspective .view of the small y adjustable wedgeuscd in the modified form. Figure 7 is a verticah'sectional view of the wedge shown in Figure 6 taken on the line 7 7 of Figure 6. L
Figure 8 is a horizontal, sectional view taken on the line 8-8 of Figure-7 and V Figure 9 is a perspective view of the rod used with my device. A 7
It is well known that in coal and other mine ing, it is common practice to use props for supporting the roof. For convenience in eX- plaining the structure and use ofmy collapused in coal mines. s
In mining coal, Wherever it is necessary to support the roof, it is found that the'cost of props makes a very considerable item of eX- pense. e e
Heretofore it has not generally been the practiceto remove the props after they were installed, because the difficulty of such removal made the expense too great. r
Itis my purpose to provide a device which vcan be used for installing the props and which will permit theconvenient, quick andeasy removal of the props. i
In coal mining in some sections of the country, it has now become common practice tomine alongv a long face instead of in rooms. The Vroof is supported by props, andas the mining loperations advance,` the rear .propsy may be removed and the roofallowed to drop. Heretofore the removal of the props has been so expensive as to be prohibitive. With my device, the props can be removed at a very moderate expense and usedrepeatedly.
In Figure 1, I have illustrated the manner in which my device can be used. 1
A plate or blockor thelike indicated by the reference numeral 10 is placed on the mine floor. My collapsible ywedgestructure com,- prising the blocks-12and 14 is supported on the block 10. On my lcollapsible wedge structure, I place an ordinary propv16 in upright i position. On the upper end ofthe may be placed a block or cap 12. i
After thevprop has served its purpose for a sufficient length of time, my collapsiblewedge Y prop may Vbe structui'e is released and the taken out and used elsewhere.
prop V16 y `My improved collapsible wedge structure is i shown in one form in Figures 1 and2 andl in another form in Figures 3 to 8 inclusive.
I install-in the form shown inFigures 1 and 2, the blocks 12 and 14. The. block 12 has a flat bottom and an inclined upper face20. The face 2Oy is inclined from what I will for convenience call the rear facei12a of the block 12 downwardly and forwardly from the horizontal.
I have forV convenience indicated the; end
` faces of theblock 12 by the numerals 12"r and The front face of the groove 22'indicated at 22a is arranged in aplane at right angles toV 'the plane of the face 20. f' sible wedge structure, I will refer to 1t as it 1s The groove 22 is deep enough toy wholly receive a heavy rod 24, preferably of steel. f
For coacting with the block-12, I preferably f provide the block 14, having the upper face time for removal arrives.
The under-face of the block 14 indicated at 26 is beveled to correspond to the bevel of the face 2O and is provided with a longitudinal groove 28 of such depth as to receive somewhat less than half of the cylindrical rod 24.
In the use of my collapsible wedge struc ture, the block 12 is placed on the base 10 in the proper location. I then partially lill the groove 22 with sand 30. The sand 3() is filled to such a height as to support the rod 24 in position for projecting above the face 2O suiliciently to substantially and snugly fill the groove 28.
The block 14 is then placed in position where the groove 28 receives the rod 24.
The prop 16 is set on the block 14 and the cap 18 inserted snugly under the mine roof. If the roof sags any, it rests on the structure thus ciected and will be held against falling.
After the prop has served its purpose, I drill out a portion of the sand 30. It will be understood that removable gates 30, held in place by guides 30h, are used to hold the sand in place at the ends of the groove 22 until the After aA portion of the sand 30 has been taken out in any convenient way, the block 12 may be tapped, whereupon the sand will drop, thus permitting the rod 24 to drop, whereupon the block 14 will slide down the face 2O and the supporting structure will be collapsed. The blocks 12 and 14 are preferably of cast metal but may be of any suitable material.
In Figures 3 to 8 inclusive, I have shown a slightly different form in which my collapsible wedge block can be embodied.
In this modified form, I' use a block similar to the block 12 provided with the groove 34 similar to the groove `22.
Midway of the groove 34, I provide an offset recess 36 extending toward the rear wall of the face 32L of the block 32. A threaded hole 38 extends from the lower part of the recess 36 to the face 32a. A screw 40 is threaded into the hole 38. The screw 40 has the out-er head 40a, and at its inner end theV reduced neck 40'J and the enlarged head 40C.
Slidable in the recess 36 and groove 34, I provide a small wedge or block 42, having the forward beveled face 42a. rear, central part of the wedge 42 is a slot 44, which at its inner endhas an enlarged portion 46. The slot 44 is intended to receive the reduced neck 4()ID of the screw 40 and the enlarged portion of the slot as at 46 receives the head 40c rotatably.
In the modied form of my device, the block 14 is the saine as that shown in Figure 1.
In installing the parts for use, the block 32 is placed on the base 1() `in the manner already described. y
The screw 40 is rotated for forcing the small wedge 42 to its forward limit of movement, where it projects into the groove 34 In the lower as shown in Figure 4. The rod 24 is then dropped into place in the groove 34 resting on the upper part of the beveled face 42a.
The block 14` is `placed in position with less than halll of the rod 24 projecting into the groove 28. y
The prop may be installed in the usual way.
After small wedge 42 into the recess 36 and permitting the beveled face of the block 14 to slide down the upper beveled face of the block 32.
It will be seen that when the parts are installed as shown in Figure 4 for holding thc prop 16 in place, the block 14 will tend to force the rod against the right-hand face 34a of the Vslot 34, which `lies `in a plane at right angles to that of the top face of the block 32, and that there is very little downward pressure on the rod 24. There is enough tendency, however, to-force the rod 24 downwardly, so that when the small wedge 42 is removed, the rod 24 will drop down.
W'ith a device of this kind, a very great saving can be effected in mines. Props can be used over andV over again, and they can be removed from the place of installation quickly and cheaply enough to malte the removal profitable.
It will be understood that I do not by my present claims intend to limit myself to any particular details of construction or kinds Vof material, and that it is my purpose toV .cover by my claims any modiiied forms of` structure or use of mechanicalequivalents, which may be reasonably included within' the scope ofmy claims.
I claim as my invention:
1. In a wedge block structure of the class described, a pair of blocks having respectively a horizontal lower and a horizontal Y the prop has served its purpose, the screw 40`inay be manipulated for pulling the upper face and having 4adjacent vbeveled faces inclined from the horizontal, said blocks having in their adjacent faces registering horizontal recesses, a cylindrical niember received in said recesses, and movable means for holding said cylindrical member in raised position, the recess in the lower block being of suliicient depth to permit the cylindrical member to drop downwardly thereinto when the movablemeans is removed from such recess.
2. In a device of the class described,a pair of blocks having respectively a lower horizontal and an upper horizont-al face and having adjacent'beveled faces, said blocks having in said beveled faces registering hori-A VZontal recesses, an adjustable round faced member adapted to be partially received in the respective recesses in said blocksymeans for holding said last-above described means in raised position adapted to be moved to position for permitting said adjustable ineinllo ber to drop into the recess in the lower block to thus permit the upper block to slide freely froln the lower block. Y
3. In a device of the class described, a pair of blocks having respectively lower and upper horizontal faces and having adjacent beveled faces, one block being superposed upon the other, said blocks having in their adjacent faces horizontal registering grooves, a cylindrical rod received in said grooves, the lower face ofthe groove in the lower block being arranged in a plane substantially at right angles to that of the beveled face of said block, and movable means for holding said cylindrical member in raised position with less than half of its bulk projected into the groove in the upper block.r
4. In a device of the class described, a pair i of blocks having respectively lower and upper horizontal faces and having adjacent -beveled faces, one block being superposed rupon the other, said blocks having in their adjacent faces horizontal registering grooves, a cylindrical rod received in said grooves, the lower face of the groove in the lowerblock being arranged in a plane substantially at right angles to that of the beveled face of said block, and movable means for holding said cylindrical member' in raised position with less than half of its bulk projected into the groove in the upper block, said means comprising a slidable wedge, and means for adjusting said wedge to different positions for holding said movable member up or permitting it to drop intov the groove in the lower block. l
' 5. In a device of the class described, a pair of blocks having coacting adjacentbeveled faces, said faces being provided with horizontal, transverse recesses adapted to register with each other when one of the blocks is superposed above the other, a member having a rounded upper face received in the recess in the lower block and capable of vertical up and down movement partially into and en# tirelyv out of the recess in the upper block, and means for controlling the up and down movementof said member.
6. In a device of the class described, a pair of blocks having coacting adjacent beveled faces, said faces being provided with transverse recesses adapted to register when one block is superposed upon the other, the recess in the lower block vhaving its lower side wall portion arranged in a plane substantially at right angles to that ofthe beveled` face of the lower block, a member adapted to travel into and out of the recess in thel lower block along said face in an up and down movement, and means for controlling such movement of said member.
7. In a device of the class described, a pair of blocks having respectively lower and upper horizontal faces and khaving adjacent beveled faces, said blocks having in their adjacent faces transverse horizontal recesses adapted to register when the upper block is superposedupon the other block, a substantially cylindrical member received in the recess in the lower block and adapted to be projected into the recessin the upper block, and movable'means :for holdingl said cylindrical member in raised positionpartially projected into the recess in the upper block adapted to be moved to position for permitting the cylindrical member to move downwardly bodily into the recess in the lower block. l
8. In a device of the class described, a pair of blocks, one of which is adapted to be superposed upon the other, the adjacent faces of the block having transverse recesses adapted to register when one block is thus superposed upon the other, a member adapted to travel up and down in said recesses having a recess in the upperblock having a facek of corresponding shape, and means for controlling the up and down movement of said member. l'
i 9. In a device of the class described, a pair of blocks having coacting adjacent beveled faces, said faces being provided with horizontal transverse recesses adapted to register with each other when one of the blocks is superposed on the other, a locking member having a rounded upper face receivedfin the recess in the lower block and capable of substantially lvertical up and down ymovement partially into and entirely out of the recess in the upper b'loclr, and means for support ing such member in raised position partially projected into the upper block and kadapted to be moved away from such supporting position.
10. In a device of the class described, a
pair ofv blocks having coacting adjacentv beveled faces, said faces being provided with 1 transverse recesses adapted to register when one block is superposed upony the other, the
recess in the lower block having its lower side wall arranged in a plane substantially at right angles to kthat ofthe beveled upper face of the lower block, a cylindrical member received 'in the lower transverse recess capable of movement upward to project for less than half its bulk into the upper recess, and means for holding the member raised capable ofv 85 face in the form of a part of a cylinder, the
US197737A 1927-06-09 1927-06-09 Collapsible wedge block Expired - Lifetime US1714024A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US197737A US1714024A (en) 1927-06-09 1927-06-09 Collapsible wedge block

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US197737A US1714024A (en) 1927-06-09 1927-06-09 Collapsible wedge block

Publications (1)

Publication Number Publication Date
US1714024A true US1714024A (en) 1929-05-21

Family

ID=22730557

Family Applications (1)

Application Number Title Priority Date Filing Date
US197737A Expired - Lifetime US1714024A (en) 1927-06-09 1927-06-09 Collapsible wedge block

Country Status (1)

Country Link
US (1) US1714024A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3394522A (en) * 1966-03-11 1968-07-30 Maurer Fritz Connecting apparatus for prefabricated structural elements
US3814363A (en) * 1972-12-22 1974-06-04 Gen Electric Angled levelling foot for domestic appliance
DE2722425A1 (en) * 1976-05-21 1977-11-24 Richier Sa ARRANGEMENT FOR CONNECTING THE PARTS OF A METALLIC SUPPORTING FRAME
US20130111829A1 (en) * 2011-11-07 2013-05-09 Oscar PEDRAZA Pre-fabricated anchor block and rotatable anchor rod
US20140246555A1 (en) * 2011-07-28 2014-09-04 Sirtres S.R.L. Rest Foot for Stabilizers

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3394522A (en) * 1966-03-11 1968-07-30 Maurer Fritz Connecting apparatus for prefabricated structural elements
US3814363A (en) * 1972-12-22 1974-06-04 Gen Electric Angled levelling foot for domestic appliance
DE2722425A1 (en) * 1976-05-21 1977-11-24 Richier Sa ARRANGEMENT FOR CONNECTING THE PARTS OF A METALLIC SUPPORTING FRAME
US20140246555A1 (en) * 2011-07-28 2014-09-04 Sirtres S.R.L. Rest Foot for Stabilizers
US20130111829A1 (en) * 2011-11-07 2013-05-09 Oscar PEDRAZA Pre-fabricated anchor block and rotatable anchor rod

Similar Documents

Publication Publication Date Title
US1714024A (en) Collapsible wedge block
US1895053A (en) Prop for mines and means for withdrawing the same
US3183581A (en) Leveling device
US3418814A (en) Roof supports for mine workings
US3052008A (en) Panel-supporting stringer assembly for a concrete floor slab
US1606025A (en) Extensible leg
US2121291A (en) Roof support for underground passageways
US2692109A (en) Shelf supporting structure
US1969014A (en) Adjustable joist framer
US3576110A (en) Movable support assemblies for mineral mines
US3819101A (en) Apparatus for setting pins in mine roofs
US1324076A (en) Column-cap
US2160454A (en) Supporting device
US2085975A (en) Support
US1818633A (en) Mine prop
US2711097A (en) Screed levelling devices
US2510767A (en) Form clamping support
US2666629A (en) Adjustable cutter for strip mining machines
CN206917673U (en) A kind of new type mining point post Liftable type post footwear apparatus
US2398152A (en) Adjustable support for concrete floor forms
US1990418A (en) Shoemaking stand
US2225852A (en) Coal mining tool
US2444705A (en) Adjustable shoring support
US2561642A (en) Apparatus for mining coal
GB396169A (en) Improvements in or relating to devices for use in supporting mine roots and analogous purposes