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Publication numberUS2434138 A
Publication typeGrant
Publication dateJan 6, 1948
Filing dateMar 11, 1946
Priority dateMar 11, 1946
Publication numberUS 2434138 A, US 2434138A, US-A-2434138, US2434138 A, US2434138A
InventorsAdams Cyril S
Original AssigneeAdams Cyril S
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Load indicator for cranes
US 2434138 A
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Description  (OCR text may contain errors)

Jan. 6, 1948. c, 5; ADAMS LOAD INDICATOR FOR CRANES Filed March 11, 1946 4 Sheets-Sheet l Jan. 6, 1948. c, s, ADAMS 2,4

LOAD INDICATOR FOR CRANES Filed March 11, 1946 4 Sheets-Sheet 2 PPQQQ Jan. 6, 1948. 5 5, ADAMS 2,434,138

LOAD INDICATOR FOR CRANES Filed March 11, 1946 4 Sheets-Shee 4 Q9 30a 3k 32 is operatively connected Patented Jan. e, 1948 UNITED STATES PATENT OFFICE 2,434,138 LOAD INDICATOR FOR CBANES Cyril S. Adams, Houston, Tex. I Application March 11, 1946, Serial No. 653,671 3 Claims. (CL 177-311) invention relates to a load indicator and to a load indicator for an of electrical signaling devices located at a convenient place in view of the operator with means for actuating the signals successively, as the load is increased, to warn the operator when the load limit has been reached.

In the present illustration the signaling devices consist of electric lights although audible signals may be used.

The invention also comprehends means for electrically setting the brakes on the hoisting motor to prevent overloading of the crane.

Other objects and advantages will be apparent from the following specification which is illustrated in the accompanyingdrawings, wherein:

Figure 1 is a fragmentary, side view of an overhead crane, viewed as indicated by the line I--i of Figure 2 and showing the near bridge girder partly broken away.

Figure 2 is an end elevation viewed as indicated by the line 2-2 of Figure 1.

Figure 3 is an elevation, partly in section, of the tension spring employed and associated parts.

Figure 4 is a sectional .view thereof taken at right angles to the view shown in Figure 4, and;

Figure 5 is a wiring diagram.

Referring now more particularly to the drawings wherein like numerals of reference designate the same parts in each of the figures, the numerals I and 2 designate similar spaced bridge girders which are supported at their respective ends on similar carriages, as 3. Each carriage is provided with the supporting wheels I, 4 which travel on suitably supported rails 5.

Mounted on the bridge girders are the trolley rails 6, 6 provided to support the trolley I. This trolley is provided with the supporting wheels 8, 8 which travel along the rails 6. Mounted on the trolley I there is a cable winding drum 3 which with a hoisting motor (not shown in the present drawings).

There is a traveling block l containing the sheaves II, II over which the runs l2, l2 of the hoisting cable operate. The ends of this cable are wound about the drum 3 and the lifting and the operator. The block III is equipped with the usual depending hook I3 by means of which the load to be lifted may be attached to the block.

' Mounted on the trolley I are the spaced brackets ll, II which are provided with suitable aligned bearings through which a supporting rod i extends. This rod also extends through, and supports, an upper connector l8. Spaced beneath the connector I6 is a lower connector IT. The adjacent'ends of these connectors are threaded into, or otherwise fastened to, opposing ends of lowering of the block HI may be controlled by a strong coil spring l8 which links the connectors together. This spring l8 and connectors l6, l1 may be specifically designed for each size and type of overhead crane.

The lower end of the lower connector i1 is formed into a fork l9 and between the arms of this fork there is a sheave 20, over which the hoisting cable is looped (as shown in Figure 4) and which sheave is mounted to rotate on a spindle 2| whose ends have hearings in the arms of the fork l9.

There is a bridle formed of the side links 22, 22. The rod l5 passes through the upper ends of these side links so that they are suspended therefrom and the lower ends of the side links have aligned vertical slots 23, 23 through which the ends of the spindle 2i extend. The links 22, 22 are spaced from the upper connector by means of the spacers 24, 24 which are located between said links and said connector and through which the rod l5 extends and the lower ends of said links are spaced from the yoke l9 by the spacers 25, 25 which are located between said lower connector and said yoke and through which the spindle 2| extends. The lower ends of the links 22 are maintained against spreading and rotation by means of washers 26, 26 which are keyed on to their respective ends of the spindle 2i.

The bridle above described limits the range of downward movement of the lower'connector l1 relative to the upper connector It in the event of any structural failure of the spring I8 or the connectors l6 and i1, thus preventing an accident as a result of such failure.

As illustrated in Figures 4 and 5 there is a series of contacts 21, 28, 29, 30, 3i and 32, which are mounted on the supporting plate 33 fixed to v the upper connector i6 and there is a flexible contact arm 34 one end of which is fixed to a suitable anchor 35 carried by the supporting plate 36 which is mounted on the lower connector [1. The other end of said arm 34 is adapted to successively form electrical connections with the contacts 21 to 32, inclusive.

There is an indicator panel 31 in front 01 the operator stationed in the operator's cab 38 and on this panel are the weight-indicating electrical signal lights which indicate the load supported from the traveling block I 0. As an illustration the light 21a may indicate a relatively light load, the light 28a may indicate a heavier load and so on with the lights 29a, Ma, Ma and 32a all as predetermined for each application. These lights are connected with the respective contacts 21 to 32, inclusive, by the wiring 21b, 28b, 29b, 30b, Nb, and 32b, which, in turn, are also connected into the main electrical conductors 39 and 40, the later of which is electrically connected with the contact arm 34.

There is also a shut-down contact 4| with which the contact arm forms an electrical connection when a predetermined load limit has been reached and which is connected into the main circuit through the wiring 42. A relay 43 is connected into the circuit 42 and is adapted to operate an audible alarm, or a brake mechanism, or both, designated generally by the numeral 44. The brake mechanism, if used, is provided to set the brakes on the hoisting motorto prevent excessive overloading of the crane and the audible alarm is arranged to operate immediately prior to the setting of the brakes.

Wired into the main electrical circuit are also a series of trouble lights 21c, 28c, 29c, 30c, 3lc and 320. These lights are arranged to correspond with the signal lights 21a to 32a, respectively. They are constantly illuminated except when the circuit through the corresponding signal light is out of order and are provided to indicate to the operator whether or not the signal lights are in working order. They are of high resistance and therefore will be constantly illuminated, when the signal lights are in order.

There is a resistor 45 connected to the conductor 40 and which is in series with the contact arm 34 so as to provide suiiicient voltage across said resistor to illuminate the lights 21c to 32c, inelusive, while the contact arm 34 is in contact with any one of the contacts 21 to 32, inclusive, and at which time signal light, corresponding to the contact with which the contact arm 34 is in electrical connection, will be illuminated.

The electrical conductors 39 and 40 lead to the panel 31 from the source of electrical energy. From the panel to the contacts electrical conductor 40 and electrical conductors 21b through 32b and also electrical conductor 42 are enclosed within a suitable flexible cable, as 48, or they may be in the form of rigid conductors fastened directly to the crane.

It is, of course, obvious that the lower connector I! may be supported directly from the crane and the upper connector may be mounted yieldingly on the spring is and the sheave 20 suspended from said upper connector. This would be merely a reversal of parts and the spring It would then be a compression spring. In this connection it is to be noted generally that the drawings and description disclose only what is now considered to be a preferred form of the invention by way of illustration, merely, while the broad principle of the invention will be defined by the appended claims.

What I claim is:

1. In a, load indicator for overhead cranes, a e tension signal actuating unit comprising, an upper connector suspended from the crane trolley, a lower connector, a coil spring into whose ends the adjacent ends of the connectors are threaded, said spring linking the connectors together yieldingly, a series or electrical contacts stationary with respect to one connector, a contact member fixed relative to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative movement of said connectors.

2. In a load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector suspended from the crane trolley, .a lower connector, a coil spring into whose ends the adjacent ends of the connectors are threaded, said spring linking the connectors together yieldingly, a series of electrical contacts stationary with respect to one connector, 9. contact member fixed relative to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative movement of said connectors, and a series of electrical signals electrically connected with the series of electrical contacts.

3. In a load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector, a lower connector, one of said connectors being attached to the crane, a helical spring directly linking the connectors together, a load supporting sheave mounted on the other connector, a bridle including side links whose upper ends are attached to the crane and with which the sheave has a limited, slidable, connection, a series of electrical contacts stationary with respect to one connector, 8. contact member stationary with respect to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative movement of said upper and lower connectors,

4. In a load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector attached to the crane, a lower connector, a tension spring linking the connectors together, a load supporting sheave mounted on the lower connector, a bridle including side links whose upper ends are attached to the crane and with whose lower ends the sheave has a limited, slidable, connection, a series of electrical contacts stationary with respect to one connector, a contact member stationary with respect to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative movement of said upper and lower connectors, and a series of electrical signals which are electrically connected with the respective electrical contacts.

5. In a load indicator for overhead cranes, a line tension signal actuatingunit comprising, an upper connector attached to the crane, a lower connector, a tension spring linking the connectors together, a bridle including side links whose upper ends are attached to the crane. and whose lower ends are formed with oblong, vertical bearings, a sheave axle on the lower connector whose ends are slidable in said bearings, a load supporting sheave mounted on said axle and electrical contact members on said connectors relatively movable with said connectors to complete an electrical circuit to a signal device.

6. In a. load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector attached to the crane, a lower connector, a tension spring linking the connectors together, a bridle including side links whose upper ends are attached to the crane and whose lower ends are formed with oblong, vertical bearings, a sheave axle on the lower connector whose ends are slidable in said bearings, a load supporting sheave mounted on said axle, a series of electrical contacts stationary with respect to one connector, a contact member stationary with respect to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative movement of said connectors.

7. In a load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector, 9. lower connector, one of said connectors being attached to the crane, a helical spring yieldingly supporting the other connector and linking the connectors together, means for attaching a load to the yiei'dingly mounted connector, means for limiting the range or movement of one connector relative to the other connector, a series of electrical contacts stationary with respect to one connector, a contact member stationary with respect to the other connector, said contact member and contacts being arranged to form successive electrical connections upon relative moveme t of said connectors under the influence of said load and a series of electrical signals electrically connected with the series of electrical contacts.

8. In a load indicator for overhead cranes, a line tension signal actuating unit comprising, an upper connector, a lower connector, one of said connectors being attached to the crane, a helical spring connected tosaid connectors linking n. s. ADAMS.

REFERENCES CITED The following references are of record in the file 'of this patent:

UNITED STATES PATENTS Number Number Name- Date Bull Jan. 22, 1895 Larson Dec. 16, 1913 Riley Aug. 28, 1917 Cardone Mar. 25, 1919 Butusov Apr. 20, 1926 Hallenbeck Dec. 13, 1932 Hallenbeck Dec. 13, 1932 FOREIGN PATENTS Country Date Great Britain Feb. 19, 1920 France Mar. 17, 1921

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2544128 *May 24, 1947Mar 6, 1951Bell Arthur WDeep-sea fishing game
US2601144 *Jun 22, 1948Jun 17, 1952Walter P BarrettLoad-carrying safety switch
US2607834 *Mar 1, 1948Aug 19, 1952Highway Trailer CoElectrically controlled depth indicator for boring machines
US2637525 *Jun 30, 1949May 5, 1953Yale & Towne Mfg CoHoist limit mechanism
US2649992 *Mar 22, 1947Aug 25, 1953American Mach & FoundryArticle storing and dispensing apparatus
US2727724 *Jul 14, 1952Dec 20, 1955Jacob J BiebighauserFishing apparatus
US2769945 *Aug 12, 1952Nov 6, 1956Republic Steel CorpElectric crane scale repeater
US3233746 *Apr 23, 1964Feb 8, 1966Joseph E FawellHoist safety device
US3683355 *Jan 4, 1971Aug 8, 1972Eastern Rotorcraft CorpCable load indicator
US3696667 *Apr 22, 1970Oct 10, 1972Inductosyn CorpTensioning device for position measuring transformer
US3796322 *Nov 24, 1972Mar 12, 1974Heede Int IncCrane trolley indicator
US4140010 *Sep 1, 1977Feb 20, 1979Demag AktiengesellschaftLoad test apparatus for hoisting units by means of strain gages
US4222551 *Sep 29, 1978Sep 16, 1980Francois SimonPulley-block weighing-balance
US4395920 *Jan 13, 1981Aug 2, 1983Audio Dynamics CorporationDigital stylus force gauge
US5662311 *May 13, 1996Sep 2, 1997Harnischfeger CorporationLifting apparatus including overload sensing device
US6829952Feb 12, 2003Dec 14, 2004Automotive Systems Laboratory, Inc.Seat belt tension sensor
US6843143Jun 9, 2003Jan 18, 2005Automotive Systems Laboratory, Inc.Seat belt tension sensor
US7090200 *Nov 26, 2002Aug 15, 2006Morse Christopher JActuator
US20120182150 *Jan 19, 2011Jul 19, 2012Chiung-Yi ChiangActuator having load weighting mechanism
Classifications
U.S. Classification177/48, 340/666, 73/862.641, 254/270, 200/85.00R, 212/283, 212/278, 177/147, 340/685, 73/862.56, 200/16.00R, 73/862.625
International ClassificationG01G19/00, G01G23/18, G01G3/00, G01G3/02, G01G23/36, B66D1/58, G01G19/18, B66D1/54
Cooperative ClassificationG01G19/18, B66D1/58, G01G23/362, G01G3/02
European ClassificationB66D1/58, G01G3/02, G01G19/18, G01G23/36B