US1818584A - Lifting device - Google Patents

Description

A 1 I w. SCHROEDER 1,818,584 LIFTING DEVICE Filed Jan. 11, 1930 2 Sheets-Sheet 1 llillvllll //V VIA/70F W SCI-M05059 Patented Aug. 11, 1931 UNITED STATES PATENT OFFICE A WILLIAM SCHROEDER, OF ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK L IFTING DEVICE Application filed. January 11, 1930. Serial No. 420,065.

This invention relates to lifting devices, and more particularly to a lifting device or grapple for cylindrical objects, such as cable reels.

An object of the present invention is to provide a lifting device of simple and durable construction, and which may be safely and expeditiously manipulated for lifting and moving objects of various sizes.

One embodiment of the invention contemplates the provision of a lifting device or grapple for handling cable reels, wherein a motor driven worm within a casing actuates a gear for rot ting the entire grapple 115 if free, or if prevented from rotation by the reel being handled, the gear operates a member threaded in a sleeve having a coneshaped friction surface for causing a pair of arms to engage the ends of the reel. A

. go pair of horizontal members are slidable vertically upon the arms and serve to center the grapple with respect to the reel, and thereafter prevent displacement of the reel. Limit switches in the motor circuit and included in the arms of the yoke connected with the usual cable for preventing undue rotation of the casing around its vertical axis respond when abnormal conditions are encountered to prevent further rotation in one direction while permitting rotation in the reverse direction.

These and other features and advantages of the invention will become apparent from the following detailed description, reference being had to the accompanying drawings, wherein Figs. 1 and 2 are front and side elevational views, respectively, of a grapple embodying it will be observed that a casing or framework is indicated generally by the numeral 10 and comprises upper and lower halves 11 and 12, respectively. Rotatably journalled in the casing 10 is a vertical hollow shaft 14 which projects through the bottom of the casing and terminates in a frustroconical portion 15, upon which is rotatably suspended a yoke member 16. The yoke member 16' terminates in a bifurcated portion for pivotally supporting oppositely disposed angular gripping members 20-20, each comprising a short horizontal arm 21 and a relatively long vertical arm 22. It will be observed that the horizontal arms are pivoted between their ends in the bifurcated extremities of the yoke. A vertical screw member'24 is threaded in the hollow shaftor sleeve 14 and is axially movable therein upon the rotation of the shaft with respect to the member. The member 24 projects beyond the lower side of the casing as well as shaft 14 and is formed with an enlarged head portion 25 for pivotally interconnecting with the extremities of the arms 21. '7"; Within the casing a gear 26 is keyed or otherwise secured to the sleeve 14, the sleeve and gear being supported upon ball bearings 27 resting upon a portion of the exterior wall of the casing. The gear is connected by means of reducing gear 29 with a worm 30 secured upon and rotated by a horizontal shaft 31 suitably supported in ball bearings and having one end projecting from the casing for attachment through a suitable coupling 32 to a shaft 33 of an electrical motor 34 mounted upon the exterior of the casing. Thus, when the motor is started, the gear 26 is rotated causing a corresponding rotation of the sleeve 14.

Each arm 22 has suitably secured thereto at the lower end thereof, a pair of angularly disposed extensions 37 terminating in inwardly projecting portions 88 for engaging the underside of the periphery of the article to be lifted, such as a shipping reel of cable or wire 40. Horizontal bracket members 42 are mounted upon the arms 22 so that they are free to slide upwardly or downwardly when maintained in thehori: im

zontal plane. The ends of the brackets are provided with apertures through which rods or tubes are past to interconnect the corresponding ends of the bracket members. Sufficient clearance is provided in the brackets so that the rods are freely slidable therethrough as well as rotatable therein, thus permitting a free relative movement of the rods through the arms 22 during the opening and closing thereof. The ends of the rods are flanged to prevent the displacement thereof from the bracket members.

An eye or loop member 47 is pivoted to the casing 10 for supporting the entire cable or lifting device from a hook 48 suspended through the usual cable or tackle of any suitable hoisting crane of the cantilever arm type, not shown in detail since it is unnecessary to a complete understanding of the invention.

For convenience, the improved grapple is preferably constructed so that it may be rotated either in a clockwise or a counterclockwise direction. .In the present embodiment of the invention, the direction of rotation of the grapple is reversed by reversing the direction of rotation of the operating motor For this reason, the motor 34 is series wound and operated by direct current from a battery 44 (Fig. 6) or other suitable source. A reversible switch 45 is provided in the operating circuit of the motor for reversing the direction of the current flow in the field winding 46 of the motor 34 to reverse the direction of rotation of the motor and thereby the grapple.

Means is provided for automatically opening the motor operating circuit upon a pre determined abnormal strain during the rotation of the grapple in either direction. The usual guide wire 50, familiarly known as the tag line ofthe crane, extends over a pulley 51 on the arm 52 of the crane and terminates in a yoke or bifurcated portion 53, the extremities of which are pivotally attached to operating rods 5454 of limit switches 55 and 56 rigidly secured to the exterior of casing 10 on opposite sides thereof (Figs. 3 and Each limit switch consists of a fixed contact member 57 and a movable contact member 58 carried by the operating rod 54, the contacts being maintained in a closed condition normally due to the effect of 'a coil spring 59 surrounding the rod 54. hen an abnormal strain is placed upon either of the arms of the yoke 53, the rod 54 of the associated switch is arranged to thereby open the contact members thereof although the corresponding. members of the other switch are maintained closed.

Referring to Fig. 6, it will be noted that when contact terminals 6O and 61 of the reversing switch 45 are closed, an electrical operating circuit of the motor is completed which may be traced as follows: from the battery 44, through motor armature 84, switch terminal 60, switch 45, motor field winding 46 in the direction indicated by the arrow 62, switch 45, switch terminal 61, and contacts 57 and 58 of limit switch 55 to battery. The grapple may now be rotated by the motor in a clockwise direction. When an abnormal strain is encountered during such rotation, the contacts of the limit switch 55 are opened, therebyopening the electrical operating circuit of the motor and thus preventing further rotation of the grapple in a clockwise direction. However, by opening the contact terminals 60 and 61 of the reversing switch 45 and closing contact terminals 63 and 64 thereof, the motor maybe operated to rotate the grapple in a counterclockwise direction. In this instance, the electrical operating circuit of the motor may be traced as follows: from the battery. 44, through motor armature 34, switch terminal 60, switch terminal 64,switch 45, motor field winding 46 in the direction indicated by the arrow 65, switch 45, switch terminal 63, and contacts 57 and 58 of limit switch56 to battery. The limit switch 56 operates as described above in connection with the limit switch 55 to open the motor operating circuit when an abnormal strain is encountered during the rotation of the grapple in a counter-clockwise direction.

It is to be understood that the embodiment of the invention herein illustrated and described is merely a convenient and useful form of the invention which is capable of other applications within the scope of the appended claims.

IVhatis claimed is 1; In an article liftingdevice, a suspended framework, a pair of opposing arms pivoted thereon and terminating in article engaging elements, means for causing a relative movementof the arms to engage the elements with the periphery of the article at a plurality of points below the center of gravity thereof, and a plurality of members interconnecting and freely slidable upon the arms for engaging the upper portion of the periphery of the article to. preventits displacement from the elements.

2. In an article lifting device, a suspended framework, a plurality of article engaging arms secured thereto, means for rotating the arms as a unit ina constant relative relationship around a vertical axis, "and means responsive to the engagement of the arms with a fixedly positioned article toconvert the rotating movement of the arms into a relative movement'thereof to cause the arms to support the article.

3. In an article lifting device, a casing, a motor mounted thereon, a shaft driven thereby and having worm within the easing, a worm gear withinthe casingmeshing with the worm, a vertical sleeve also in the casing rotated by the gear and having an internally threaded portion, a member threaded thereinto, a head carried thereby, and a plurality of arms pivotally attached to the casing and the head and actuated by a longitudinal movement of the member caused by the rotation of the sleeve.

4- In an article lifting device, a suspended framework, a vertical sleeve carried thereby having a conical exterior surface at the lower end thereof, means for rotating the sleeve, a spider frame surrounding the sleeve and having a conical surface cooperating with the first mentioned conical surface to support and provide a friction drive for rotating the spider in response to the rotation of the sleeve, and means secured to the spider for supporting an article.

5. In an article lifting device, a suspended framework, means terminating in a bifurcated yoke for preventing the rotation of the framework about the vertical axis thereof, relative movable article engaging means supported by the framework, means for causing a relative movement thereof to engage an article, means for rotating the article in either direction independently of the framework, and means in the yoke responsive to a predetermined opposing force in the rotation of the article in a direction to prevent the further rotation thereof in that direction while permitting the rotation thereof in the reverse direction.

6. In an article lifting device, a framework, suspending means therefor, means for preventing the rotation of the framework about the vertical axis of the suspending means, article supporting means earned by the framework, an electrical motor for rotating the supported article in either direction independently of the framework, an electrical circuit therefor, and means in the circuit responsive to a predetermined force for preventing rotation of the article 1n one direction while permitting the rotation thereof in the reverse direction.

7 In a device for lifting a cylindrical article, a suspended framework, a pair of arms secured thereto and terminating in portions for engaging the lower portion of the periphery thereof and supporting an article, a horizontal member freely slidable upon each arm and extending on each side thereof, and a freely horizontal cylindrical member interconnecting the opposing ends of the hori- Zontal members for engaging the upper portion of the article at spaced points to prevent a displacement of the article from the pair of arms.

8. I11 an article lifting device, a framework, a pair of opposing arms pivoted thereon, each terminating in article engaging elements, means slidably carried by the arms for centering them upon an article and means for causing a relative movement of the arms to engage and thereby support an article.

9. In an article lifting device, a plurality of article engaging members, means for rotating the members as a unit in constant rel- 7 members to firmly grip the article.

10. In an article lifting device, a framework, a member rotatably carried thereby having a conical exterlor surface, means for rotating the member, a frame having a conical surface cooperating with the first conical surface to support and provide a friction drive for rotating the frame through the rotation of the member, and means carried by the frame for supporting an article.

11. In an article lifting device, a framework, article supporting means carried by the framework, means for rotating the supported article independently of the framework, and means responsive to a predetermined opposing force encountered in the rotation of the article for preventing further rotation thereof.

12. In an article lifting device, a framework, article supporting means carried by the framework, an electrical motor for rotating the supported article independently of the framework, an electrical circuit therefor, and means responsive to a predetermined opposing force encountered in the rotation of the article for opening the circuit to stop the motor.

13. In an article lifting device, a frame work, article supporting means carried by the framework, means including an electrical motor and an operating circuit therefor for rotating the supported article in either of a plurality of directions independently of the framework, and means including a plurality of limit switches connected in the motor operating circuit and responsive to a predetermined opposing force encountered in the rotation of the article in one of said directions for preventing further rotation of the article in that direction while permitting the rotation ofthe article in another of said directions.

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

WILLIAM SCHROEDER.

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