US2701121A - Automatic soil coring machine - Google Patents

Automatic soil coring machine Download PDF

Info

Publication number
US2701121A
US2701121A US222725A US22272551A US2701121A US 2701121 A US2701121 A US 2701121A US 222725 A US222725 A US 222725A US 22272551 A US22272551 A US 22272551A US 2701121 A US2701121 A US 2701121A
Authority
US
United States
Prior art keywords
soil
chain
tube
coring
coring tube
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
US222725A
Inventor
Almond D Bull
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 US222725A priority Critical patent/US2701121A/en
Application granted granted Critical
Publication of US2701121A publication Critical patent/US2701121A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B49/00Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
    • E21B49/02Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells by mechanically taking samples of the soil

Definitions

  • This invention relates to a power-driven machine to be used in making rapid soil profile examinations. It particularly relates to an apparatus which presses a soil coring tube into the ground and brings out a core specimen of the soil profile.
  • One object of this invention is the employment of a coring tube having an open side, or longitudinal opening, through which the unaltered soil profile can be observed without removal from the tube.
  • Another object is to press the tube into the soil without any twisting action or vibration in order that an open face tube of this kind can be employed.
  • a further object is to provide a soil coring apparatus that automatically limits the downward movement of the colging tube, to control the depth of the core sample ta en.
  • a still further object is to provide a soil coring apparatus that automatically limits the extent of upward movement of the coring tube.
  • Figure 1 is an assembled view of the apparatus
  • Figure 2 is a side view of the apparatus of Figure l, in the plane 2--2;
  • Figure 3 is a section in the plane 3-3;
  • Figure 4 is a longitudinal section of the lower end of the coring tube
  • Figure 5 is a diagram of an electric battery powered circuit and switches for starting, stopping, and reversing the electric motor that moves the coring tube;
  • Figure 6 is a detail of the clutch mechanism forming part of the power-takeofl from the electric motor.
  • the apparatus is primarily designed to be mounted upon a motor-propelled car or truck, the coring tube extending downwardly through the floorboard. It may be used on a tractor or operated as an auxiliary self-propelled unit.
  • the cylindrical coring tube 76 is provided with a longitudinal opening or open face 761 ( Figure 1) through which the specimen core may be examined.
  • a soil coring point 49 provided with a short cylindrical section 491 of the same inside diameter as cutting edge of soil coring point 49 and parallel to the longitudinal axis of soil coring tube 76 and from this point upward provided with an upwardly flaring conical bore 490.
  • the diameter of the top of bore 490 is the same as that of cylindrical bore 760.
  • the diameter at the lower cutting edge of bore 490 and cylindrical section is slightly less than that of bore 760.
  • the cylindrical section must be long enough to hold onto the cored soil and not too long. Otherwise, friction would prevent cutting a full length core.
  • Tube 76 is removably attached to driving sleeve 68 by means of a pin 762 on tube 76 which fits in slot 680 of the sleeve.
  • the sleeve 68 is rigidly attached to a face of block 69 which in turn is rigidly attached to and mounted upon a link of an endless push-pull chain 5.
  • Roller chain 5 is driven by lower sprocket 48, and is supported by and moves over upper idling sprocket 67.
  • the chain is in effect a cable or rigid rod that pulls or presses the coring tube into the ground and then Patented Feb. 1, 1955 out rotational movement of the tube and of the core sample within the tube. The extraction of the tube is also without twisting the tube.
  • the cable or chain provides a steady downward thrust without jarring and significant impact and without application of any forces which could twist the coring tube.
  • the push-pull roller chain is constrained to move within two guide channels 74, which are rigidly attached to and supported by beam 75. Since the endless chain 5 preferably functions as a vertically moving rigid rod or cable, it must be kept taut within the guide channels. Tension of this chain is obtained by adjusting idler sprocket 67 upwardly and downwardly by means of supporting slotted bars 78, which are adjustably secured to the beam 75 by means of studs 79.
  • Sprocket 48 is turned by electric motor 3, which is of the reversing type.
  • Motor 3 turns shaft 57 and pulley 58, moves V-belt 59, turns pulley 60, jack-shaft 62, and roller drive chain 42.
  • This turns sprocket 47 and operates car transmission 66 when the latter is set in low gear.
  • Power is thus applied by motor 3 to turn clutch shaft 43 and friction drive pressure plates 44 which are attached to the shaft by Allen screw 51 and half-moon key 50.
  • the friction drive pressure plates are held firmly against clutch facing discs and friction driven pressure plates 46, which are welded to drive sprocket 48, by compression spring 53.
  • the spring is held tightly by adjusting nut 56 on threaded section of clutch shaft 43. This causes power to be applied to drive sprocket 48. If an obstruction is encountered, the movement of the roller chains automatically stops, through slippage of the friction clutch.
  • Provision for automatically stopping movement of the soil coring tube at the proper place is provided for by operation of limit switch 12 located at base of I-beam 75 ( Figure 1) and limit switch 13 located at the top of beam 75.
  • the limit switches are actuated by the movement of the chain which carries coring head drive block 69 up and down.
  • the coring head drive block 69 moving downwardly carries stop-pin 70 into contact with lever 71 which is attached to limit switch mounting bracket 72. Movement of lever 71 ( Figure l) compresses spring 39 to allow limit switch 12 to operate thereby breaking the circuit and causing push-pull roller chain 5 to stop.
  • push button switch 6 When it is desired to lift the soil coring tube 76 out of the soil, push button switch 6 ( Figure 5) is operated to close the circuit from battery 4, through conductor 15, contacts 18 and 20, conductor 23, through limit switch 13 (closed by spring 339), contacts 25 and 27 and through conductor 29. This closure of the circuit by push button switch 6 allows current to flow through conductor 29 and 40 to energize solenoids 31 of reversing switches 10 and 11, the circuit being completed at ground 30. Current from battery 4 then flows through conductors 15 and 38, through contacts of reversing switch 11, through conductor 34 and the motor field winding in reverse direction and through conductor 36, contacts of reversing switch 10, conductor 32, motor armature 372, conductor 17, to battery 4. This causes operation of the motor in the opposite direction so that power is transmitted to the roller chains in reverse direction, the soil coring tube being lifted out of the soil.
  • Limit switch 13 located at top of I-beam 75, becomes operative when the chain 5 carries stop-pin 70 into contact with lever 711 to compress spring 339 and thereby break the circuit and stop movement of the soil coring machine.
  • An apparatus for obtaining a soil profile core specimen comprising: a coring tube having an earth penetrating edge at its lower end, the coring tube having a longitudinally extending aperture for observation of the soil profile, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for upward and downward movement of the chain, the upper part of the coring tube being attached to a link of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to vertical upward and downward movement between these points.
  • a coring tube having an earth penetrating edge at its lower end and having an aperture for observation of the soil profile specimen extending longitudinally along a major part of its length, power driven means for pressing the coring tube into the soil in a direction longitudinal to its length and without torque, and a limit switch to limit the extent of downward movement into the soil.
  • An apparatus for obtaining a soil profile core specimen comprising: a coring tube having an earth penetrating edge at its lower end, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for up ward and downward movement of the chan, the upper part of the coring tube being attached to a link of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to vertical upward and downward movement between these points.
  • An apparatus for obtaining a soil profile core specimen comprising: a cor-ing tube having an earth penetrating edge at its lower end, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for upward and downward movement of the chain, the upper part of the coring tube being attached to a link of the chain, a manually operated control to initiate the downward movement of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, a manually operated control to initiate the upward movement of the chain, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to straight upward and downward movement between these points.

Description

Feb. 1, 1955 A. D. .uu. 2,
AUTOMATIC soxL CORING MACHINE Filed April 24, 1951 2 Sheets-Sheet 2 INVENT OR ALMQND D.BULL@ ATTORNEY United States Patent AUTOMATIC SOIL CORHIG MACHINE Almond D. Bull, Woodward, Okla.
Application April 24, 1951, Serial No. 222,725
4 Claims. (Cl. 255-1.4)
(Granted under Title 35, U. S. Code (1952), sec. 266) The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes throughout the world without the payment to me of any royalty thereon.
This invention relates to a power-driven machine to be used in making rapid soil profile examinations. It particularly relates to an apparatus which presses a soil coring tube into the ground and brings out a core specimen of the soil profile.
One object of this invention is the employment of a coring tube having an open side, or longitudinal opening, through which the unaltered soil profile can be observed without removal from the tube.
Another object is to press the tube into the soil without any twisting action or vibration in order that an open face tube of this kind can be employed.
A further object is to provide a soil coring apparatus that automatically limits the downward movement of the colging tube, to control the depth of the core sample ta en.
A still further object is to provide a soil coring apparatus that automatically limits the extent of upward movement of the coring tube.
One embodiment of the invention is illustrated in the drawings, in which:
Figure 1 is an assembled view of the apparatus;
Figure 2 is a side view of the apparatus of Figure l, in the plane 2--2;
Figure 3 is a section in the plane 3-3;
Figure 4 is a longitudinal section of the lower end of the coring tube;
Figure 5 is a diagram of an electric battery powered circuit and switches for starting, stopping, and reversing the electric motor that moves the coring tube;
Figure 6 is a detail of the clutch mechanism forming part of the power-takeofl from the electric motor.
The apparatus is primarily designed to be mounted upon a motor-propelled car or truck, the coring tube extending downwardly through the floorboard. It may be used on a tractor or operated as an auxiliary self-propelled unit.
The cylindrical coring tube 76 is provided with a longitudinal opening or open face 761 (Figure 1) through which the specimen core may be examined. To the lower end of the tube is attached a soil coring point 49 provided with a short cylindrical section 491 of the same inside diameter as cutting edge of soil coring point 49 and parallel to the longitudinal axis of soil coring tube 76 and from this point upward provided with an upwardly flaring conical bore 490. The diameter of the top of bore 490 is the same as that of cylindrical bore 760. The diameter at the lower cutting edge of bore 490 and cylindrical section is slightly less than that of bore 760. The cylindrical section must be long enough to hold onto the cored soil and not too long. Otherwise, friction would prevent cutting a full length core. Tube 76 is removably attached to driving sleeve 68 by means of a pin 762 on tube 76 which fits in slot 680 of the sleeve. The sleeve 68 is rigidly attached to a face of block 69 which in turn is rigidly attached to and mounted upon a link of an endless push-pull chain 5.
Roller chain 5 is driven by lower sprocket 48, and is supported by and moves over upper idling sprocket 67. The chain is in effect a cable or rigid rod that pulls or presses the coring tube into the ground and then Patented Feb. 1, 1955 out rotational movement of the tube and of the core sample within the tube. The extraction of the tube is also without twisting the tube. The cable or chain provides a steady downward thrust without jarring and significant impact and without application of any forces which could twist the coring tube. The push-pull roller chain is constrained to move within two guide channels 74, which are rigidly attached to and supported by beam 75. Since the endless chain 5 preferably functions as a vertically moving rigid rod or cable, it must be kept taut within the guide channels. Tension of this chain is obtained by adjusting idler sprocket 67 upwardly and downwardly by means of supporting slotted bars 78, which are adjustably secured to the beam 75 by means of studs 79.
Sprocket 48 is turned by electric motor 3, which is of the reversing type. Motor 3 turns shaft 57 and pulley 58, moves V-belt 59, turns pulley 60, jack-shaft 62, and roller drive chain 42. This turns sprocket 47 and operates car transmission 66 when the latter is set in low gear. Power is thus applied by motor 3 to turn clutch shaft 43 and friction drive pressure plates 44 which are attached to the shaft by Allen screw 51 and half-moon key 50. The friction drive pressure plates are held firmly against clutch facing discs and friction driven pressure plates 46, which are welded to drive sprocket 48, by compression spring 53. The spring is held tightly by adjusting nut 56 on threaded section of clutch shaft 43. This causes power to be applied to drive sprocket 48. If an obstruction is encountered, the movement of the roller chains automatically stops, through slippage of the friction clutch.
When it is desired to force the soil coring tube into the ground push button switch 7 is closed. Current flows from battery 4 through conductor 15, the contacts 19 and 21 of switch 7, conductor 22, the contacts 24 and 26 of limit switch 12 and through conductors 28 and 41. This flow of current through conductors 28 and 41 energizes solenoids 31 of reversing switches 8 and 9, the circuit being completed at ground 30. Closure of the solenoid switches causes current to flow from battery 4, through conductors 15 and 38, reversing switch 9, through conductor 37 and motor field winding 371 and through conductor 35, reversing switch 8, conductor 33, armature of motor 372 and conductor 17, to battery 4 to complete the circuit. The motor is then operating in the direction to cause the push-pull roller chains to move downward over idler sprocket 67 in the channel guides 74.
Provision for automatically stopping movement of the soil coring tube at the proper place is provided for by operation of limit switch 12 located at base of I-beam 75 (Figure 1) and limit switch 13 located at the top of beam 75. The limit switches are actuated by the movement of the chain which carries coring head drive block 69 up and down. The coring head drive block 69 moving downwardly carries stop-pin 70 into contact with lever 71 which is attached to limit switch mounting bracket 72. Movement of lever 71 (Figure l) compresses spring 39 to allow limit switch 12 to operate thereby breaking the circuit and causing push-pull roller chain 5 to stop.
This controls the depth to which the soil coring tube will enter the soil.
When it is desired to lift the soil coring tube 76 out of the soil, push button switch 6 (Figure 5) is operated to close the circuit from battery 4, through conductor 15, contacts 18 and 20, conductor 23, through limit switch 13 (closed by spring 339), contacts 25 and 27 and through conductor 29. This closure of the circuit by push button switch 6 allows current to flow through conductor 29 and 40 to energize solenoids 31 of reversing switches 10 and 11, the circuit being completed at ground 30. Current from battery 4 then flows through conductors 15 and 38, through contacts of reversing switch 11, through conductor 34 and the motor field winding in reverse direction and through conductor 36, contacts of reversing switch 10, conductor 32, motor armature 372, conductor 17, to battery 4. This causes operation of the motor in the opposite direction so that power is transmitted to the roller chains in reverse direction, the soil coring tube being lifted out of the soil.
As the soil coring tube moves upwardly, provision is made for automatically stopping it at the proper place. Limit switch 13, located at top of I-beam 75, becomes operative when the chain 5 carries stop-pin 70 into contact with lever 711 to compress spring 339 and thereby break the circuit and stop movement of the soil coring machine.
A non-exclusive, irrevocable, royalty-free license in the invention herein described, for all governmental purposes, throughout the world, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.
Having thus described my invention, I claim:
1. An apparatus for obtaining a soil profile core specimen comprising: a coring tube having an earth penetrating edge at its lower end, the coring tube having a longitudinally extending aperture for observation of the soil profile, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for upward and downward movement of the chain, the upper part of the coring tube being attached to a link of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to vertical upward and downward movement between these points.
2. In an apparatus for obtaining a soil profile specimen: a coring tube having an earth penetrating edge at its lower end and having an aperture for observation of the soil profile specimen extending longitudinally along a major part of its length, power driven means for pressing the coring tube into the soil in a direction longitudinal to its length and without torque, and a limit switch to limit the extent of downward movement into the soil.
3. An apparatus for obtaining a soil profile core specimen comprising: a coring tube having an earth penetrating edge at its lower end, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for up ward and downward movement of the chan, the upper part of the coring tube being attached to a link of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to vertical upward and downward movement between these points.
4. An apparatus for obtaining a soil profile core specimen comprising: a cor-ing tube having an earth penetrating edge at its lower end, power driven means for applying a pressing force adjacent its upper end, in a direction longitudinal to the coring tube, said means including a roller chain and power driven means for upward and downward movement of the chain, the upper part of the coring tube being attached to a link of the chain, a manually operated control to initiate the downward movement of the chain, a limit switch positioned to automatically stop the chain when the core has been pushed downwardly to the desired point, a manually operated control to initiate the upward movement of the chain, another limit switch to automatically stop the chain when it has been retracted upwardly from the soil to the desired point, the chain being restrained to straight upward and downward movement between these points.
References Cited in the file of this patent UNITED STATES PATENTS 464,252 Knoepfel et al. Dec. 1, 1891 544,475 Booth et a1 Aug. 13, 1895 971,791 Prisk Oct. 4, 1910 1,109,446 Melberg Sept. 1, 1914 1,317,875 Hansen Oct. 7, 1919 1,919,461 Burke et al. July 25, 1933 2,181,873 Cregar Dec. 5, 1939 2,459,383 Levy Jan. 18, 1949 2,564,188 Burg et a1. Aug. 14, 1951
US222725A 1951-04-24 1951-04-24 Automatic soil coring machine Expired - Lifetime US2701121A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US222725A US2701121A (en) 1951-04-24 1951-04-24 Automatic soil coring machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US222725A US2701121A (en) 1951-04-24 1951-04-24 Automatic soil coring machine

Publications (1)

Publication Number Publication Date
US2701121A true US2701121A (en) 1955-02-01

Family

ID=22833420

Family Applications (1)

Application Number Title Priority Date Filing Date
US222725A Expired - Lifetime US2701121A (en) 1951-04-24 1951-04-24 Automatic soil coring machine

Country Status (1)

Country Link
US (1) US2701121A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2856158A (en) * 1956-01-09 1958-10-14 Texas Co Sampling apparatus
US3179186A (en) * 1962-03-19 1965-04-20 Almond D Bull Rotary soil coring apparatus
US5125266A (en) * 1990-03-27 1992-06-30 Fugro-Mcclelland Leasing, Inc. Self-contained apparatus and method for determining the static and dynamic loading characteristics of a soil bed
US5127261A (en) * 1990-03-27 1992-07-07 Fugro-Mcclelland Leasing, Inc. Self-contained apparatus and method for determining the static and dynamic loading characteristics of a soil bed
US20060107772A1 (en) * 2004-11-22 2006-05-25 Shinn James D Ii Subsurface material property measurement

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US464252A (en) * 1891-12-01 Ernest g
US544475A (en) * 1895-08-13 Measuring-tool
US971791A (en) * 1909-02-09 1910-10-04 John Prisk Earth-hole-forming machine for weed-exterminating purposes.
US1109446A (en) * 1913-11-03 1914-09-01 Miller L Melberg Soil-tester.
US1317875A (en) * 1919-10-07 hansen
US1919461A (en) * 1931-10-30 1933-07-25 Ralph H Burke Method of and means for taking soil tests
US2181873A (en) * 1937-11-06 1939-12-05 Nat Automatic Tool Co Combination directional drilling and tapping unit
US2459383A (en) * 1945-12-07 1949-01-18 Ecusta Paper Corp Sampling device
US2564188A (en) * 1946-11-20 1951-08-14 Stanolind Oil & Gas Co Portable drilling equipment

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US464252A (en) * 1891-12-01 Ernest g
US544475A (en) * 1895-08-13 Measuring-tool
US1317875A (en) * 1919-10-07 hansen
US971791A (en) * 1909-02-09 1910-10-04 John Prisk Earth-hole-forming machine for weed-exterminating purposes.
US1109446A (en) * 1913-11-03 1914-09-01 Miller L Melberg Soil-tester.
US1919461A (en) * 1931-10-30 1933-07-25 Ralph H Burke Method of and means for taking soil tests
US2181873A (en) * 1937-11-06 1939-12-05 Nat Automatic Tool Co Combination directional drilling and tapping unit
US2459383A (en) * 1945-12-07 1949-01-18 Ecusta Paper Corp Sampling device
US2564188A (en) * 1946-11-20 1951-08-14 Stanolind Oil & Gas Co Portable drilling equipment

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2856158A (en) * 1956-01-09 1958-10-14 Texas Co Sampling apparatus
US3179186A (en) * 1962-03-19 1965-04-20 Almond D Bull Rotary soil coring apparatus
US5125266A (en) * 1990-03-27 1992-06-30 Fugro-Mcclelland Leasing, Inc. Self-contained apparatus and method for determining the static and dynamic loading characteristics of a soil bed
US5127261A (en) * 1990-03-27 1992-07-07 Fugro-Mcclelland Leasing, Inc. Self-contained apparatus and method for determining the static and dynamic loading characteristics of a soil bed
US5339679A (en) * 1990-03-27 1994-08-23 Fugro-Mcclelland Leasing, Inc. Self-contained apparatus and method for determining the static and dynamic loading characteristics of a soil bed
US20060107772A1 (en) * 2004-11-22 2006-05-25 Shinn James D Ii Subsurface material property measurement
US7234362B2 (en) 2004-11-22 2007-06-26 Applied Research Associates, Inc. Subsurface material property measurement

Similar Documents

Publication Publication Date Title
DE4019895C2 (en) Method and device for controlling the operation of handheld electrical devices
US2701121A (en) Automatic soil coring machine
AT413350B (en) DRIVE FOR CUTTING VEHICLES ON A SHUTTER CUTTING MACHINE
EP2517814B1 (en) Drilling machine, in particular hand-held core drilling machine
DE10228141A1 (en) Cooking appliance
ATE38265T1 (en) FISHING GEAR.
US4977965A (en) Automatic drop hammer system
DE2028195A1 (en) Switching device for electrically operated window panes of vehicles, in particular of motor vehicles
US1816258A (en) Means for opening and closing windows
DE202006006478U1 (en) Device particularly motor operated traversing unit, has electromechanical component, which has rotating mechanical part for control function, acoustic signaling function of electromechanical component is assigned
US4667933A (en) Gear transmission for a winch
EP0191730A1 (en) Door-actuating device to open or close a door automatically
US2839294A (en) Automatic opening and closing means for overhead doors
US3072193A (en) Swab pump for oil field production
US3406765A (en) Soil sampling apparatus
GB2145795A (en) Improvements in or relating to a mechanical transmission
US2317544A (en) Coring tool
US3223402A (en) Door closer
US3026951A (en) Hydraulic soil sampler
EP3564419B1 (en) Bale opener with a height-adjustable pickup unit and a brake unit for same
DE733071C (en) Shooting range equipment with retractable and retractable target
US2240823A (en) Bundling press compression control
DE2821547A1 (en) Drive for lift cage speed limiter - has rope and pulley held on swivelling pulley for release of safety switch
DE420476C (en) Mechanical relay
DE1099908B (en) Device for automatic cable slip compensation for power-operated pulley pulling devices