US1950057A - Operating mechanism for grab-buckets - Google Patents

Operating mechanism for grab-buckets Download PDF

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US1950057A
US1950057A US597367A US59736732A US1950057A US 1950057 A US1950057 A US 1950057A US 597367 A US597367 A US 597367A US 59736732 A US59736732 A US 59736732A US 1950057 A US1950057 A US 1950057A
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drum
motor
shaft
rolling
gearing
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US597367A
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Lange Johann Friedric Heinrich
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Firm Of Eisenwerk (vorm Nagel & Kaemp) AG
Firm Of Eisenwerk Vorm Nagel &
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Firm Of Eisenwerk Vorm Nagel &
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66CCRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C3/00Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith and intended primarily for transmitting lifting forces to loose materials; Grabs
    • B66C3/12Grabs actuated by two or more ropes
    • B66C3/125Devices for control

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  • Fig. 2 shows in a similar sectional and diagrammatic view a second constructional form of such mechanism.
  • FIG. 3 The practical construction of Fig. 3 is fundamentally in conformity with that shown in Fig. 2, and is illustrated solely by way of example of carrying my invention into practice.
  • Operating mechanism for grab-buckets or the like comprising a drum, a motor for rotating said drum, said motor being mounted stationary 120 with respect to said drum, a second drum, a carrier for said second drum, a second motor for rotating said second drum, said second motor causing a relative rotational movement between said second drum and said carrier, means for also rotating said second drum by said first motor, and two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other set of rolling gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely upon the motor to which it appertains.
  • a shaft a drum mounted on said shaft, a motor within said drum for rotating said drum, a second shaft, a second drum mounted upon said second shaft, said second shaft being coupled to said motor for rotation therewith, a motor within said second drum for causing a relative rotational movement between said second drum and said second shaft, two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely from the motor to which it appertains, a special carrier for each set of rolling gearing, each carrier having a stud passing through one of the front walls of its drum, and means associated with each carrier for taking up the torque of said stud outside of the drum.

Description

March 6, 1934. J. F. H. LANGE 1,950,057
OPERATING MECHANISM FOR GRAB BUCKETS I Filed March 7, 1932 Jmerzrr: J F: H. L a. n a,
Patented Mar. 6, 1934 OPERATING DIECHANISM FOR GRAB-BUCKETS Johann Friedrich Heinrich Lange, Hamburg, Germany, assignor to the firm of Eisenwerk (vorm. Nagel & Kaemp) A. G., Hamburg, Germany Application March 7, 1932, Serial No. 597,367 In Germany March 5, 1931 12 Claims. (o1.254 1s5) My invention relates to operating mechanism for automatic grab-buckets or the like having two drums and two motors.
The object of the invention is to provide an op- 5 crating mechanism for grab-buckets which is simple in structure, economical in manufacture, and efiicient in operation.
A further object of the invention is to provide an operating mechanism of the kind referred to comprising a drum for hoisting the grab-bucket and a second drum for racking or closing and opening the bucket, in which mechanism the additional rotational movements of the closing and opening drum are generated by means other than planetary gears, which have been used hitherto for this purpose. Thus the disadvantages inherent to planetary-gearing, such as low-efiicien cy, are avoided.
Further objects of the invention will appear more fully hereafter.
The invention consists substantially in the combination and arrangement of parts as shown in the accompanying drawing in which Fig. 1 is a diagrammatic representation, partly sectional, of one form of construction of my improved operating mechanism.
Fig. 2 shows in a similar sectional and diagrammatic view a second constructional form of such mechanism.
Fig. 3 is a longitudinal section through a practical embodiment of the operating mechanism in accordance with the form shown in Fig. 2.
Referring to Fig. 1 of the drawing an electric motor a or its equivalent is provided, to the shaft of which a pinion b is connected. Gears 0 and d are fastened to shafts e and 1, respectively, and
are coupled with each other by the pinion b.
(The bearings of the shafts are not shown.) Upon the shafts are arranged drums g and h respectively adapted to take up ropes or cables which may be wound upon each of said drums or may be unwound from them. Motor a is adapted to drive both drums simultaneously in order to permit simultaneous hoisting or closing and opening movement. One of the drums, i. e. drum h, must be driven independently in order to permit closing or opening movements independent from hoisting movements.
In order to permit this separate drive of drum h the following arrangement is made. Drum g is fast upon its shaft e whereas drum h is loose upon its shaft f and may be rotated thereon. Further, shaft f carries in any convenient manner, e. g.
by means of its gear d, the second motor 1', the
pinion of which is in mesh with a toothed rim It provided on drum h.
As long as the motor i is without current and is braked up in any convenient manner, it produces a rigid coupling between drum h and its shaft I so that both are either at rest or are rotated as a unit by the motor a. There is at this time, no relative movement between the parts i, k, m, regardless of whether the motor a is at rest or is running at any speed whatsoever.
It will thus be seen that provided the motor 1 is not energized, the motor a will drive the drum h along with the drum g in the following manner: The pinion 1) drives the gear :1, and since the motor i is braked in any suitable manner during 76 its inoperative period, and since it is mounted directly on the gear :1, it rotates therewith. The pinion m of the motor i, is locked against rotation due to the braking of the said motor 1, and thus transmits the torque of the gear it directly to the gear is formed on the drum h, thereby rotating the latter. Now, if the brake of the motoriis released and such motor is energized, the pinion m will rotate under the action of the driving motor 2 and will cause the independent rotation of 80 the drum h, regardless of whether or. not the motor a is energized. Should the two motors a and i be energized simultaneously, the motori will rotate about the drum h, due to the rotation of the gear d, and will at the same time drive the drum h 35 due to the rotatory meshing of the pinion m and gear It, so that a differential action is obtained, resulting from the algebraic summation of the rotations of the gear d and pinion m.
If, however, motor 1' is receiving current and is running, a relative movement is caused by it between drum h on the one hand and its shaft f or its gear d respectively, on the other hand. The amount of this relative movement is entirely independent of whether or not shaft ,1 is driven by motor a, and if driven, at what speed it is running. It is only this relative movement which is of importance. It is not essential that the motor i, causing this relative movement or rotation, is revolving together with gear d or with drum shaft f. Motor i might be arranged in such a manner as to revolve together with the drum, as is shown in the second constructional form.
In this second form, as represented in Fig. 2, the armature 103 is arranged as a stator and is 105 mounted upon a shaft 104 non-rotatably held in the frame (not shown). The field magnets 101 of the motor are carried by the drum 9, rotatably mounted upon shaft 104. Drum g is provided with a. gear 0' in mesh with another gear d, which is fast upon a shaft I rotatably mounted in the frame and carrying the armature 3' of the electromotor i. The field magnets 1' of this motor are arranged upon the inner wall of the drum In. Each of the motor-shafts has a braking disk 18 and 118, respectively arranged fast upon it, towards which the axially movable drums are urged by suitable means such as a spring (not shown) so long as the motor is not running.
The motor i being current-less, the drum n is coupled by means of the braking .disk 18 to the shaft f for simultaneous rotation. The shaft 1' being connected through gears d and c to drum g. the motor a rotates both drums simultaneously and at the same speed.
If however the motor a is without current, the drum 9' is secured against rotation by the braking disk 118 so that gears c and d are held stationary. Shaft ,f' is likewise then held stationary. If then motor 2" is set in motion it drives drum h alone and rotates it. If both motors a and i are running simultaneously, the rotating movement caused by the latter is superposed, that is. added to or subtracted from those rotations, which are imparted to drum h by drum 9'.
The operation, therefore, is the same as that of the construction shown in Fig. 1. Fig. 2 shows, however, very clearly, that no gears at all are necessary for the generation of the relative or superposed drum rotation, whereas in known constructions for the same purpose, gears are always needed. In other words: From Fig. 2 it becomes especially apparent that the relative or superposed rotational movement of the drum is not due to the construction and/or arrangement of the gearing but to the peculiar arrangement of the rack motor.
The practical construction of Fig. 3 is fundamentally in conformity with that shown in Fig. 2, and is illustrated solely by way of example of carrying my invention into practice.
The drums H and G are shown reversed from their position in Fig. 2 and are mounted in a common frame R with their axes parallel to each other. Drum H is rotatable relatively to its drum shaft or stud F carrying a gear D which is in mesh with a gear C which is adapted to rotate with drum G.
A motor A is arranged within the drum G, a second motor J being arranged within the drum H. The drums are rather similar to each other as regards their construction and dimensions in order to simplify their manufacture as much as possible.
The driving mechanism of the rack drum H is constructed and operated as follows:
The left front wall 23 of the drum H, the mantle of which is formed as a motor casing and carries the field magnets 1, is integral with a hollow shaft 22 arranged in line with the axis of the drum and mounted in a stationary bearing 21. The hollow shaft carries three collector rings 24, to which the current for the field coils is led by means of the brushes of a brush holder mounted upon hearing 21. (The wires and electrical connections have not been shown for simplicity's sake.) The rotor 3 of the motor is carried by a shaft 4 which is supported by the front wall 23 in a ball bearing 25 and which passes through the hollow shaft 22. Upon its end three collector rings 26 are provided to which the current for the armature is led by means of the brushes of a brush-holder 2'7. (Here also the electrical wires and connections are not shown.)
The end of shaft 4 passes through a central opening of a transverse wall 28 of the drum and is supported in a ball bearing 5' and tightened by a packing 14. Upon the end of shaft 4 a pinion 6 is arranged. The front wall 28 is provided with an annular groove for forming a hollow stud 11 upon which a disk 10 is rotatably held. 'Ihis disk is connected by studs 9 with another disk 10' mounted parallel and rotatable, both disks forming a rigid frame.
The disk 10' has an extension in the direction of its axis forming the stud F passing through the right front wall 29 of the drum and supported by ball bearing 11' and tightened by a packing ring 14'. The stud F is mounted in a stationary mounting 13 of frame R and carries-as mentioned-the gear D fast upon it. Spur gears 7 are arranged upon the studs 9 and are in mesh with pinion 6. They are further integral with pinions 31, which are in mesh with a rim 8 being toothed on the inside, said rim being screwed on drum cover 29.
1 The operation of this mechanism is as folows:
The motor arranged within the drum H gencrates a relative rotational movement between the pinion 6 and the toothed rim 8. If the gearing carrier 9, 10, 10' is held stationary the gears '7 revolving upon the studs 9 cause with the pinions 31 the rotation of the drum H.
The drums G and H are provided on their outer surface with grooves for reception of the ropes.
The following arrangement prevents the rotation of the drum under the weight of the load by braking the operating mechanism when the current for the motor is cut out.
The field coil 15 of the magnets 1 are constructed so as to form an annular cylindrical recess. A cylindrical magnet core 16 projects into this recess and is supported by a brake-body 17 shiftably mounted within drum H. Sliding springs 20 are provided for avoiding a rotation of the brake-body relative to the drum. Upon shaft 4 a brake disk 18 is arranged having a conical rim engaging the conically machined brake surface of brake-body 17 when said body is shifted towards the left under the action of a spring 19. Spring 19 surrounds the shaft 4 and engages on one side the rotor 3, and on the other side the brake-body 17. By the braking effect a relative rotational movement of shaft 4'with respect to drum H is prevented and the drum is braked. If the armatures 1 are under current the brake-body 17 is attracted by the armatures against the action of the spring 19 and the brake is released so that the brake disk 18 fixedly held by the motor shaft 4 may rotate. The arrangement of the collecter-rings outside of the bearing 21 renders them readily accessible. It will be of advantage to cover the collector-rings and the brushes with a protecting cap 32.
The gearing of drum G corresponds to that of drum H. For this reason the parts are designated by reference numbers differing from those 140 of drum H only in that the numeral 100 has been added to each of them.
A difference between the two gearings resides only in that the front wall 129 is integral with a sleeve E surrounding the stud 112, said sleeve the frame R. by a wedge 130.
The operation of the device of Fig. 3 is as follows: It is to be kept in mind that the driving drum of Fig. 3 is the upper drum G. Upon energlzation of the field A of the drum. G, the magnetic core 116 of the solenoid brake is attracted, thus breaking the connection by the brake or clutch 108, 117. The armature or core 103', corresponding to the core 103 at the right of Fig. 2, is movable, and accordingly the drum G, released for rotation by the removal of the braking faces, rotates at a rate dependent upon the ratio of reduction gearing or set of rolling gears 106, 107, 131, and 108, the said drum carrying with it the face plate 129 and the hub E of the latter. Thus, the gear C fixed thereon is rotated, and the gear D rotates therewith, transmitting torque to the shaft F, so that the latter causes the rotation of the core 3, corresponding to the core 3' at the left of Fig. 2. This transmission of torque is brought about due to the fixed mounting of the disc 10' and hence of the carrier 10', 9, and 10, when considered in conjunction with the fact that motor J being inoperative, the solenoid brake 18, 17, prevents relative rotation between the shaft 4, and hence the pinion 6, and the drum H. Thus the torque from the gear D is transmitted through the shaft F, the disc 10, the gear '7 and pinion 6 through shaft 4, and brake 17, 18 to the drum H, so that this assemblage of elements rotates bodily as a unit.
Now, assuming the motor A to be deenergized, the brake of the drum G holds the latter against rotation. Energization of the motor J in the drum H causes an additional turning moment of the said drum, to be compounded with that derived from the motor A of the drum G in the manner outlined in the foregoing. In short, energization of the motor J, and still assuming the motor A to be deenergized, brings about the rotation of the drum H through the reduction gear or second set or rolling gears 6, '7, 31, and 8, and since the brake 16, 17, is declutched and since the drum H rotates loosely about the shaft F it is only the drum H which rotates, and no torque is transmitted to the gear D.
Now let us assume that both motors A and J are energized, that both brakes are released, and that the core 3 of the motor J is rotated along with the drum H under the influence of the motor A in the manner previously described, while at the same time the motor J tends to operate independently in the marmer described immediately preceding. Thus, the rotation of the core 3 produces a differential action as concerns the cutting of the lines of flux by the field 1 so that the rotational speed of the drum H represents a compounding or the algebraic summation of the rotational speeds imparted thereto by the rotation of the core 3 through the gear D, and y the rotation imparted to the core 3 by the motor J, considered separately.
The superposition of the rotational movements is obtained in all constructional forms without planetary gears or the like. The gears inserted according to Fig. 3 between the motor and the drum or its stud respectively in no way are acting in the manner of planetary gears, although revolving as a whole on account of being arranged within the drum. The gears 6, 7, 8, and 31, as regards their rolling or revolving speed, that is to say, the number of teeth coming into mesh in each unit of time, are controlled solely by the motor J of the drum H. On the other hand the gears 106, 107, 108, 131 are exclusively under the control of motor A of the drum G at the same 'gearings it is therefore of no effect whether the motor not appertaining to this special gearing is stationary or is rotating. Therefore the conditions of movement are entirely different from those to be found in planetary gearing.
What is claimed is:
1. Operating mechanism for grab-buckets or the like, comprising two drums, two motors, one of which drives both drums simultaneously, the second motor driving only one of said drums, a carrier for the drum driven by said second motor, means for causing said second motor to generate a relative rotational movement between said drum driven by it and said carrier, and two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other set being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely upon the motor to whichit appertains.
2. Operating mechanism for grab-buckets or the like, comprising two drums, two motors for driving said drums, one of said motors driving both drums simultaneously, the second motor driving only one of said drums, a carrier for the drum driven by said second motor, said second motor being mounted for generating a relative rotational movement between said drum driven by it and said carrier, and two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other set of gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely upon the motor to which it appertains.
3. Operating mechanism for grab-buckets or the like, comprising a drum, a motor for rotating said drum, said motor being mounted stationary 120 with respect to said drum, a second drum, a carrier for said second drum, a second motor for rotating said second drum, said second motor causing a relative rotational movement between said second drum and said carrier, means for also rotating said second drum by said first motor, and two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other set of rolling gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely upon the motor to which it appertains.
4. In an operating mechanism for grab-buckets or the like a shaft, a drum mounted on said 135 shaft, 9. motor for rotating said drum, a second shaft, a second drum mounted upon said second shaft, said second shaft being coupled to said motor for rotation therewith, a second motor coupled to said second drum for rotation therewith, Said second motor causing a relative movement between said second motor and said second shaft, 9. set of rolling gearing inserted between said first drum and said first motor, and a second rolling gearing inserted between said second drum and said second motor, the rolling speed of said first set of rolling gearing being controlled solely by said first motor and not by said second motor, the rolling speed of said second set of rolling gearing being solely controlled by said second motor and not by said first motor.
5. In an operating mechanism for grab-buckets or the like a shaft, a drum mounted on said shaft. a motor for rotating said drum. a second shaft, 9. second drum mounted upon said second shaft, said second shaft being coupled to said motor for 'rotation therewith, a second motor coupled to said second shaft for rotation therewith, said second motor causing a relative movement between said second motor and said second shaft, a set of rolling gearing inserted between said first drum and said first motor, and a second rolling gearing inserted between said second drum and said second motor, the rolling speed of said first set of rolling gearing being controlled solely by said first motor and not by said second motor, the rolling speed of said second set of rolling gearing being solely controlled by said second motor and not by said first motor.
6. In an operating mechanism for grab-buckets or the like, a drum, a motor within said drum for rotating it, the field of said motor being fixed with respect to said drum, a second drum, a carrier for said second drum, a second motor within said second drum for rotating it, said second .motor causing a relative rotational movement beor the like a shaft, a drum mounted on said shaft,
a motor within said drum adapted to rotate said drum, a second shaft, a second drum loosely mounted upon said second shaft, said second shaft being coupled to said motor for rotation therewith, a motor within said second drum for rotating said drum and thus causing a relative rotational movement between said second drum and said second shaft.
8. In an operating mechanism for grab-buckets or the like, a drum. a motor within said drum for rotating it, the stator of said motor being mounted stationary fixed with respect to said drum, a second drum, a carrier for said second drum, a second motor within said second drum for rotating it, said second motor causing a relative rotational movement between said second drum and said carrier, means for, also rotating said second drum by said first motor,'two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other set of rolling gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely from the motor to which it appartains, a special carrier for each set of rolling gearing, said carrier having a stud passing through one of the front walls of its drum, and means associated with each carrier for taking up the torque of said stud outside of the drum.
9. In an operating mechanism for grab-buckets or the like a shaft, a drum mounted on said shaft, a motor within said drum for rotating said drum, a second shaft, a second drum mounted upon said second shaft, said second shaft being coupled to said motor for rotation therewith, a motor within said second drum for causing a relative rotational movement between said second drum and said second shaft, two sets of rolling gearings, one of which is inserted between one of said drums and one of said motors, the other gearing being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely from the motor to which it appertains, a special carrier for each set of rolling gearing, each carrier having a stud passing through one of the front walls of its drum, and means associated with each carrier for taking up the torque of said stud outside of the drum.
10. In an operating mechanism for grab-buckets or the like a shaft, a drum mounted on said shaft, a motor within said drum adapted to rotate said drum, a second shaft, a second drum mounted upon said second shaft, said second shaft being coupled to said motor for rotation therewith, a motor within said second drum adapted to cause a relative rotational movement between said second drum and said second shaft, a set of rolling gearing inserted between said first drum and said first motor, a second set of rolling gearing inserted between said second drum and said second motor, the rolling speed of said first set of rolling gearing being controlled solely by said firstmotor 10 ets or the like, a first drum, a motor for driving no said drum, a second drum, and a second motor. and gearing whereby the first motor drives both drums, said gearing comprising a set of rolling gearing inserted between said first drum and said first motor and a second set of rolling gearing between said second drum and said second motor, the rolling speed of said first set of rolling gearing being controlled solely by said first motor and not by said second motor, the rolling speed of said second set of said rolling gearing being solely controlled by said second motor and not by said first motor.
12. Operating mechanism for grab-buckets or the like, comprising two drums, two motors, one of which drives both drums simultaneously, the second motor driving only one of said drums, a carrier for the drum driven by said second motor, means for causing said second motor to generate a relative rotational movement between said drum driven by it and said carrier, and two sets of roll ing gearings, one of which is inserted between one of said drums and one of said motors, the other set being inserted between the other drum and the other motor, each set of rolling gearing depending as to the control of its rolling speed solely upon the motor to which it appertains, and brakes associated with each drum and holding the same against rotation relative to their corresponding motors when the said motors are ii8 energized, the said brakes being released upon energization of their corresponding motors to permit rotation between the drums and their corresponding motors.
JOHANN FRIEDRICH HEINRICH LANGE.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2589172A (en) * 1947-05-26 1952-03-11 George P Wagner Level luffing crane
US2634000A (en) * 1947-04-28 1953-04-07 Charles J Ulrich Hoisting apparatus
US2675900A (en) * 1950-06-10 1954-04-20 Franklin S Malick Electromagnetic clutch operator
US6283453B1 (en) * 1997-05-26 2001-09-04 Hydralift Marine As Double mooring bollard

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2634000A (en) * 1947-04-28 1953-04-07 Charles J Ulrich Hoisting apparatus
US2589172A (en) * 1947-05-26 1952-03-11 George P Wagner Level luffing crane
US2675900A (en) * 1950-06-10 1954-04-20 Franklin S Malick Electromagnetic clutch operator
US6283453B1 (en) * 1997-05-26 2001-09-04 Hydralift Marine As Double mooring bollard

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