US1852758A

US1852758A - Material handling apparatus

Info

Publication number: US1852758A
Application number: US420064A
Authority: US
Inventors: Schroeder William
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1930-01-11
Filing date: 1930-01-11
Publication date: 1932-04-05
Anticipated expiration: 1949-04-05

Description

p 5, 1932- SCHROEDER 1.8523

MATERIAL HANDLING APPARATUS Filed Jan. 11, 1950 //7 Vzf/Y for QRMW of six such spaced apertures are shown. Extending the entire length of the arms 2020 is a pair of stiffening flanges 47-47.

The

hooks

39, 39 consist of a body portion 50 having an upper right angular extension 51, the hook being provided with upper and lower lips 53-53 and a recess 54. The body portion 50 of the hook carries a clevis 55 which is rotatable about a pin 57 horizontally extending through the body portions.

To illustrate the operation of the device it may be supposed that it is desired to hoist the trailer from the floor level of a warehouse to an elevated gallery for storage. The hoisting crane which carries the tackle 19 is swung over the loaded trailer and, the tackle is suspended immediately above the pile of lumber 17. While in such position the parallel arms 19 are balanced to assume a substantially horizontal position, such as will facilitate their placement relative to the load, by moving the counter-weight 43 from one to the other of the

spacing apertures

46, 46, moving it centerward with reference to the length of the arms 19 if the weight of the chains 38 and hooks 39 is insulficient to overcome the weight of "the counter-weigit 43, or moving it to the extreme end of the arms 19, if it is found that the weight of the suspended chains and hooks tends-to raise the counter-weighted end of the arms 19 above a substantially horizontal position. It is important to have the arms 19 substantially horizonal or in other words parallel wih the upper surface of the lumber pile 17 in order toinsure, when the tackle has been lowered thereupon and slack produced in the hoisting chain of the crane. that it be found to lie true with the pile of lumber comprising the load. This is especially desirable to save labor and time, where, as is usually the case, the weight of the load is sufficiently great and service conditions are sufliciently severe as to require that the tackle be constructed to withstand hard service and be of a heavy construction. In such cases, it is apparent positioning of the tackle relative to the load after the full weight thereof rests upon the top of the load could only be accom plished with great difiiculty, if attempted manually by workmen standing on the ground.

' It is seldom necessary to change the position of the counter-weight 43 with reference to the apertures 46 once a generally applicable condition is established. The exceptionsare in case the size or weight of the

chains

87, 38 and 41,01 the hooks 39, be varied, or seeondly, if the position of the connecting member 21 with respect to its position relative to the center of the arms 19, is altered, as in view of circumstances to be described hereafter.

In order to insure that the tackle 18 is securely fastened to the frame so as to prevent dislodgement therefrom during handling, the special type of hookmember 89, is provided.

The body portion 50 of the hook is grasped by the operator and first inclined from the vertical sufiiciently to permit the lower portions thereof to be inserted under the longitudinal beams 12 until the beam 12 contacts with the back of the recess 5%. The hook is then lifted, causing the beam 12 to be accommodated in the depth of the recess 54. The operator then thrusts the upper part of the hook forward until the extension 51 passes beyond the top of the beam 12 and until the beam contacts with the main body portion 50 along their entire adjacent surfaces. This brings the upper lip 53 beyond the beam after which the operator permits the hook 39 to drop of its own weight, thus engaging the beam between the upper and lower lips 53-53 and the body portion 50 of the hook. The effect of such a construction is to permit the single ground operator to position the four hooks 39 successively, which he is able to do because once a hook is positioned the lips 53-53 insure its maintenance in position around the beam and the operator is thus free to proceed to the next hook without requiring the attention of other operators to insure that all the four hooks are securely in position before the load is lifted.

Due to the fact that the tackle 19 is suspended from a single point, a tendency of the load to tilt if it is inaccurately balanced with reference to the connecting member 21 becomes apparent as soon as the trailer is lifted from the ground. To overcome this, it is desirable to position the connecting member as near as possible to the center of gravity of the load. This may be accomplished by securing the depending portion 27 to the arms 19 at that aperture therein which will give the desired balanced condition. Once a balanced condition is established with reference to a typical load it will thereafter be unnecessary to change the location of the depending member 27 with reference to the arms 19 provided reasonable care is exercised in loading the lumber so as to insure that the connecting member 21 will always be as near as possible to the center of gravity of the load. In practice, it is seldom possible to locate the depending member 27 with suflicient accuracy to prevent the load 19 from tilting slightly when suspended above the ground. Any tendency of the load to shift, due to said tilting, is however, obviated by increasing the friction between the sections of lumber comprising the load.

In order to positively thus prevent shifting of the load, special features of the tackle are provided. As soon as the hooks 3939 are firmly secured over the beams 12 at the brackets 16-16, the operator of the crane begins to raise the crane hook v26, with the result that the parallel arms 19 are raised until the

chains

37 and 38 become taut. The continued elevation of the crane hook 26 coninues to raise the connecting member 21 with the result that the balanced condition of the arms is overcome and they pivot about the pin 29 and the depending member 27 Since the Ushaped band 33 is rigidly secured to that side of the arms 19 which bears the interconnecting flexible member l1, and since the

chains

37 and 38 which are connected to the U-shaped band through the aperture 35 are now taut, the continued hoisting of the crane hook 26 causes the flexible member 42 to bear downwardly until it is bound tightly across the top and from side to side of the lumber pile 17. In the arrangement shown in the drawing, wherein it will be noted that the distance between the pin 29 and the U- shaped band 33 is approximately one-third of the distance between the band 33 and the flexible member 41, distributed a downward pressure of approximately 2,000 pounds is applied to the lumber load by the flexible member 41, if the weight of the load including the trailer is approximately 6,000 pounds, as may frequently be the case. Since a downward pressure of considerably less than 2,000 pounds is ample to prevent shifting of the lumber when the trailer is tilted at any angle conceivable under service conditions, a satisfactory margin of safety is provided such as will insure that a device of the character de scribed may be successfully operated by a one man ground crew, it being necessary for him to adjust the

books

39, 39 in the manner described above.

In Fig. 2 of the drawing, a dotted line representation is included which shows the extreme inclination assumed by the arms 19 where approximately one-half of the usual load of lumber is carried. It will thereby be understood that the tackle is capable of chicient use regardless of the size of the pile of lumber 17, since the arms 19 are free to rotate through a sufficiently large angle as to permit the flexible member 42- to apply pressure upon the top of a load of lumber of any convenient size which may be contained by the platform 11 of the trailer and the connecting member 21. The operator of the hoisting engine, by lifting on the crane hook 26 and forcing the flexible member 41 downwardly against the pile is then free to hoist the loaded platform to any location within reach and through any maneuvers of which the crane is cap able without dislodging or causing any shifting between portions of the load. The pressure exerted upon the lumber pile by the flexible member 41 may be varied by changing the position of the connecting member 21. For instance, the pressure may be increased by decreasing the distance between the U-shaped band 33 and the connecting member 21 or it may be decreased by increasing the distance between the band 33 and the connecting member 21. This may be readily accomplished by removing the pin 29 and moving the depending; memben 2'! into position oven-any enema apertures. provided .fori-that; purpose: irmztbm arms 19 ,and insertingvthe; pin; 2am; it in such =p ositi,on:-..

Although the. inventionghasa been} disclosed and described as applied to an apparatuslfori handling .lumben'itiisaclear; thlatiit isi susoeptibleof numerousinodificationsstoeadapti it to handle material :of .a-nature anrliniformsi other than; thatdisclosed, and itissintenided' therefore, that the;inventiombevlimited only by the spirit; and; scope 1 of the appended claims.

What-isclaimed is;::

1. In a material handling. apparatus-,; a; platform forsupporting the material, a. flexiblemember, and a Lpivoted iarm-u for" carrying, the platform includin-g memission-retention ally; engaging: the ,flexi'ble member with; that top .ofzthe materiala In a material handling apparatumi. a; tackle comprising a ipivoted-arimandi a. flexible. member suspended therefrom; for:eIig-ag ing the material, to prevent shifting thereof when thesmaterial is lifted;

3.;Ine a; tackle, a pivoted r arm as flexible; member suspended 1therefrouiaforiengaging a loael, and means spacedfrom thepiwot point: of z' the arm-.1 01. 3 tilting thevarmuto. 03 121565 the flexible member to retentionally engage;the;

load.

i. In a a material handling; apparatus,y, a;- tacklea'ncludingia p aired} pivoted arms,-;a flex;- ible. ineinberconnected tliereto. forfretentionea ally engaging the materialandasecond'flexisi ble member: suspended therefrom. for: carry ing the. material and tori-tilting ;thei.:arm to:;. cause thezfirst fiexiblemember to engagerthe load.

5. In. a material handling apparatus,;asns.-. pension -m,eans,. an; arnr pivotedri'theretoy means associated with. 1 one end. thereofrifon: normally; zmaintaining the. army; horizontal; means; secured to the armontheoppositeaside: of the pivotal point. 1 thereof. from. the susa pension; .means, for supporting; the, material and means associated with the other en'dnof'" the-arm toxengage the supported material when .the harmuis inclinedi 6..- In a material handling apparatus, a sues: pension means, a. pair of parallel. arms pive oted thereto at; an; intermediatepoint, mas. terial supporting means piwoted :to the arms. atan; intermediate point, and. .flexibleimeansi interconnecting-the ends of thearmsonearer: the pivot, pf ;the: material supporting: means to wrap around a portion ofithenmateriali hsnsuspencleda;

7. In a.: tackle, a pivotedfarm aafiexiblei member suspended therefrom for retentixim. ally ;engagingg;a load; and asecond member suspended from the arm. for tilting the arm to cause the first member to engage the load.

8. In a material handling apparatus, a tackle including a pair of pivoted arms, a

flexible member connected to both arms for retentionally engaging the material and a second member suspended from the pair of arms carrying the materlal and for biting the arm to cause the first member to engage the load.

9. In a material handling apparatus, a suspension means, a pair of parallel arms pivoted thereto at an intermediate point, material supporting means pivoted to the arms at an intermediate point, and flexible means interconnecting the ends of the arms nearer the pivot of the material supporting means to closely engage a portion of the material when suspended.

10. In a material handling apparatus, a platform for supporting the material, a flexible member, and a pivoted arm for carrying the platform including means for retentionally engaging the flexible member with the material.

11. In a material handling apparatus, a level platform for supporting the material, a tiltable arm for carrying the platform, a flexible member at one side of the axis of the arm, means for engaging the flexible member with the material when the platform is being carried and a counterweight at the opposite side of the axis of the arm for balancing the arm.

12. In a material handling apparatus, a tackle including a pair of pivoted arms, a flexible member connected thereto for en gaging the material and a member suspended therefrom for carrying the material and for tilting the arm to cause the flexible memher to engage loads of varying heights.

18. In a material handling apparatus, a tackle including a pair of pivoted arms, a flexible member connected thereto for engaging the material and a member for engaging the material and amember suspended therefrom for carrying the material and for tilting the arm to cause the flexible member to engage the load and to conform closely to the surfaces of loads having'irregular contours.

14. In a material handling apparatus, a load supporting member, a member engageable with the load supporting member comprising a recessed hook having portions partially enclosing the recess, the aperture be tween said portions being narrower than the load supporting member, whereby a partial rotation of the hook is required to engage it with and disengage it from the load supporting member.

In Witness whereof, I hereunto subscribe my name this 27th day of December, A. D.

WILLIAM SCHROEDER.