GB1282627A - Overload safety device for jib cranes - Google Patents
Overload safety device for jib cranesInfo
- Publication number
- GB1282627A GB1282627A GB46356/69A GB4635669A GB1282627A GB 1282627 A GB1282627 A GB 1282627A GB 46356/69 A GB46356/69 A GB 46356/69A GB 4635669 A GB4635669 A GB 4635669A GB 1282627 A GB1282627 A GB 1282627A
- Authority
- GB
- United Kingdom
- Prior art keywords
- jib
- slider
- potentiometer
- voltage
- radius
- 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
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/88—Safety gear
- B66C23/90—Devices for indicating or limiting lifting moment
- B66C23/905—Devices for indicating or limiting lifting moment electrical
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Jib Cranes (AREA)
- Control And Safety Of Cranes (AREA)
Abstract
1282627 Safe-load indicator for cranes L PIETZSCH 19 Sept 1969 [16 Oct 1968 23 Nov 1968 24 Jan 1969] 46356/69 Heading G1N An overload device, Fig.1, for a jib crane comprises a plurality of strain gauges in a bridge 8 to produce a first voltage indicative of jib loading, and an arrangement which displaces the slider 4 of a potentiometer 3 in accordance with jib radius (horizontal projection of jib length), the potentiometer having a plurality of supply connections, C1 to Cn, to each of which a supply voltage is fed through adjustable switches S 1 to S n which supply voltages represent the maximum values of jib loading permissible for the respective actual values of jib radius corresponding to positions of the slider when set to the respective tapping points of the potentiometer. The slider voltage is compared with the first voltage by a discriminator 10 which actuates a relay 11 when the voltages are equal to actuate an alarm or switch off the crane. An arrangement for indicating jib radius Fig.5, includes a lead-screw spindle 11' rotatablymounted orthogonally of the axis of a telescopic jib 1', a nut 13' on the spindle, fixed against rotation, but movable longitudinally of the spindle when the latter is rotated by pulley 7' and cable 10' due to extension of the jib. A pin 18' extends from the nut to support an end of a rod 16' of which the other end is fixed orthogonally of a sleeve 17' slidable longitudinally of a pendulum bar 15', which pendulum is suspended from a fixed point 14 on the spindle axis. A rope 20' is fixed at one end to the sleeve and at the other to the drift shaft 19' of a potentiometer slider 4. Thus the distance a' between the point 14 and the sleeve varies as the jib radius lsinα where 1 is jib length and α is the angular displacement of the jib from the vertical. Alternative arrangements for indicating jib radius are illustrated in Figs.6, 7, 8 (not shown). Fig.4 (not shown) illustrates a circuit for compensating the jib load signal for variations caused by tilting of the jib. Fig.3 illustrates an alternative circuit to that of Fig.1 for use with a crane having a telescopic jib and incorporates a sine potentiometer R sα the slider 23 of which is driven by a jib angle α measuring device W, the potentiometer output voltage U α being fed to resistances R 1 , R 2 and R L in series of which R L is a potentiometer of which the slider 24 is operated by the output shaft 25 of the jib length measuring device L. So voltage U L at slider 24 is a function of lsinα where 1 is jib length. A reference voltage Ur corresponding to the position of slider 4 is taken from the slider 26 of a linear potentiometer R R across which a constant supply voltage U o is connected through resistors R 3 , R 4 . The differential voltage U L -U r is fed through an amplifier 27 to a motor M which operates sliders 26 and 4 to bring U r into equality with U L so that the slider 4 is automatically adjusted proportionally to jib radius.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19681803457 DE1803457C3 (en) | 1968-10-16 | 1968-10-16 | Overload protection for jib cranes |
DE19681810639 DE1810639C3 (en) | 1968-11-23 | 1968-11-23 | Overload protection for telescopic cranes |
DE19691903493 DE1903493C3 (en) | 1969-01-24 | 1969-01-24 | Overload protection device for telescopic cranes |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1282627A true GB1282627A (en) | 1972-07-19 |
Family
ID=27181542
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB46356/69A Expired GB1282627A (en) | 1968-10-16 | 1969-09-19 | Overload safety device for jib cranes |
Country Status (2)
Country | Link |
---|---|
US (1) | US3638212A (en) |
GB (1) | GB1282627A (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2004041C3 (en) * | 1970-01-29 | 1975-10-09 | Ludwig Pietzsch | overload protection for jib cranes, especially telescopic cranes |
US3740741A (en) * | 1971-05-26 | 1973-06-19 | Eaton Corp | Alarm set point control system |
JPS5413651B2 (en) * | 1971-12-29 | 1979-06-01 | ||
US3872458A (en) * | 1971-12-31 | 1975-03-18 | Savely Solomonov Schedrovitsky | Crane boom-out transmitter |
US3823395A (en) * | 1972-05-30 | 1974-07-09 | Trans Sonics Inc | Remote condition indicator for load-lifting device |
US3826321A (en) * | 1973-05-25 | 1974-07-30 | Trans Sonics Inc | Load weighing system for cranes with rotatable booms |
JPS5410123Y2 (en) * | 1973-10-30 | 1979-05-11 | ||
GB1456174A (en) * | 1974-03-04 | 1976-11-17 | Shimizu Construction Co Ltd | Alarm apparatus for the operaint range of cranes |
JPS5339504Y2 (en) * | 1974-03-05 | 1978-09-25 | ||
FR2282399A1 (en) * | 1974-08-20 | 1976-03-19 | Strawson Hydraulics Ltd | SAFETY DEVICE FOR CRANES |
US4752012A (en) * | 1986-08-29 | 1988-06-21 | Harnischfeger Corporation | Crane control means employing load sensing devices |
US5209361A (en) * | 1991-10-31 | 1993-05-11 | Grubb Jr Lloyd T | Multiple-cable lifting head with load weighing mechanism for aerial booms and cranes |
US10514234B2 (en) | 2013-03-27 | 2019-12-24 | Nostromo Holdings, Llc | Method and apparatus for improving the aim of a weapon station, firing a point-detonating or an air-burst projectile |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2330060A (en) * | 1941-10-28 | 1943-09-21 | Gen Electric | Safe load indicator for crane hoists |
US2858070A (en) * | 1955-11-17 | 1958-10-28 | Scharff Leon | Moment computing and indicating systems |
US3200963A (en) * | 1963-07-05 | 1965-08-17 | Laszlo G Vermes | Moment comparator |
-
1969
- 1969-09-19 GB GB46356/69A patent/GB1282627A/en not_active Expired
- 1969-10-14 US US866338A patent/US3638212A/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
US3638212A (en) | 1972-01-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1282627A (en) | Overload safety device for jib cranes | |
US3870160A (en) | Crane safe load indicator | |
US2858070A (en) | Moment computing and indicating systems | |
US3965733A (en) | Crane load inidicating arrangement | |
US4328621A (en) | Position sensing device | |
SU793371A3 (en) | Crane | |
GB1295341A (en) | ||
GB1297508A (en) | ||
CA1066083A (en) | Calibration of crane load indicating arrangement | |
US4029213A (en) | Crane load indicating arrangement | |
US4003482A (en) | Safety device for a crane | |
US3913690A (en) | Crane load indicating arrangement | |
US3490015A (en) | Safe load indicators for jib cranes | |
US3278925A (en) | Cranes | |
US3971008A (en) | Crane overload detector using a boom bending moment detector | |
US4698565A (en) | Hoist with overload safety protection | |
US2330060A (en) | Safe load indicator for crane hoists | |
US4054055A (en) | Device for controlling the load of a lifting appliance | |
US3148659A (en) | Safe load indicating devices for cranes | |
US4340847A (en) | Apparatus for supervising and controlling the output power of induction motors | |
GB815591A (en) | Improvements in or relating to safety devices for jib cranes | |
GB1393191A (en) | Jib crane with safety mechanism | |
DE1810639C3 (en) | Overload protection for telescopic cranes | |
GB1020548A (en) | Weighing apparatus | |
GB1107116A (en) | Apparatus for adjusting the loading gauge in jib cranes to various operational conditions and/or to crane systems |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |