US1945712A

US1945712A - Hoist

Info

Publication number: US1945712A
Application number: US514162A
Authority: US
Inventors: Roy J Wadd
Original assignee: Harnischfeger Corp
Current assignee: Harnischfeger Corp
Priority date: 1931-02-07
Filing date: 1931-02-07
Publication date: 1934-02-06
Anticipated expiration: 1951-02-06

Description

Feb. 6, 1934. R, J, WADD 1,945,712

HOIST Filed Feb. 7, 1931 ssnets-sneez 1 gwn/11 INVENTOR.

BY mvfwml M ATTORNEYS.

Feb. 6, 1934. R, J. WADD 1,945,712

HolsT Filed Feb. 7, 1951 5 Sheets-Sheet 2 I N VEN TOR.

dal, JAW, .w/h. www. d M

` ATTORNEYS.

Feb. s, 1934. R11. WADD 1,945,712

HOIST Filed Feb. 7, 1951 5 Smets-sheet 4 A TTORNEYS Feb. 6, 1934. R, WADD 1,945,712

HoIsT Filed Feb. 7, 1931 5 Sheets-Sheet 5 7425 VW..

5V 4: f@ y ij f/ M50 g BY 12; I fum, m, Pmww@ W ATTORNEY# Patented Feb. 6, 1934 PATENT OFFICE HOIST Roy J. Wadd, Milwaukee, Wis., assignor to Harnischfeger Corporation, Milwaukee; Wis., a corporation of Wisconsin Application February 7, 1931. Serial No. 514,162

9 Claims.

This invention relates to hoists and among the objects of the invention are to provide a hoist of simple and compact construction and wherein the major elements of the hoist, that is, the mo- 5 tor, drum and reduction gearing between the motor and drum, are so closely and advantageously organized as to provide for the smooth and easy application of the power of the motor to the drum in a balanced manner thereby prolonging the life of the hoist and insuring satisfactory and eicient operation.

Another object is to provide a hoist having these advantages and capacities and which is adaptable for various types of suspension and is constructed that its various parts are easily a cessible for purposes of inspection, adjustment, replacement or repair without the necessity of dismantling the hoist.

Another object of the invention is to provide a hoist having these advantages and capacities and which provides for the positive limitation of the upward movement of the load block in that should the load block drift excessively after the hoisting circuit is opened a lowering circuit is momentarily and automatically established whereby to l prevent positively the load block jamming into the hoist.

Other objects and advantages reside in certain novel features of the construction, arrangement and combination of parts which will be hereinafter more fully described' and particularly pointed out in the appended claims, reference being had to the accompanying drawings forming a part of this speciiication, and in which:

Figure 1 is a perspective view showing a hoist constructed in accordance with the presentinvention;

Figure 2 is a view in vertical section taken on line 2-2 of Figure 3, with parts shown in elevation for the sake of simplicity in illustration;

Figure 3 is a view in longitudinal vertical section taken in the plane of line 3-3 of Figure 5, parts being shown in elevation and parts being omitted for the sake of simplicity in illustration; Figure e is a view in transverse verticalv section taken on line 4-4 of Figure 3;

Figure 5 is a similar view on line 5-5 of Figure 3, parts being broken away for the sake of illustration;

Figure 6 is a fragmentary sectional view taken in the plane of line 6-6 of Figure 5;

Figure 7 is an enlarged view of the limit switch, the switch structure being shown partly in end elevation and partly in vertical section;

Figure 8 is a view similar to Figure 'l but showing a. different position of the switch;

Figure 9`isa sectional view taken on line 9-9 of Figure 7;

Figure 1 0 is a sectional view taken on line 10-10 60 of Figure 9;

Figure 11 is a detail view in elevation of a pullcord type of main control switch;

Figure 12 is a diagrammatic view showing the electrical circuits involved; and 65 Figure 13 is a detail section view on line 13-13 of Figure 4.

Referring to the drawings and more particularly to Figures 1, 2 and 3, the numeral 1 designates a main frame member which has the gen- 7o eral form of half a cylinder and which has end flanges 2 and 3 securely.bolted or otherwise suitably fastened as at e and 5 to the upper portions of the end plates 6 and 7 of a sectional motor housing 8 and asectional gear casing 9, respec- 75 tively. The frame member 1 is designed to be readily attached to any suitable suspension means as, for example, a hook suspension, a motor driven or other trolley or any of the various types of iixed suspensions or supports.

IThe end plate 6 of the motor housing 8 and the end plates 7 of the gear casing 9 are formed with axially alined flanged recesses 11 and12 (see Figure 3) which accommodate the end `flanges 13 and 14 of a hoisting drum designated S5 generally at 15. The hoist drum 15 is mounted for free rotation by means of a mounting sleeve 16 tted and secured in the hub o the drum and having its ends freely rotatable in anti-friction bearings, such as roller bearings, designated at 9c 17 and 18 and mounted in anged supporting members 19 and 20 carried by the central parts' of the plates 6 and 7.

An electric motor or any other suitable type of motor shown diagrammatically at M in Figure 9u 12 is `housed in the casing 8 and the motor shaft 25 projects from the casing 8 and into a coupling sleeve 26 supported in a ball bearing assembly 27 carried by the flanged portion 19' of the plate 6, (see Figure 3). The coupling sleeve 26 100 also connects with a motor shaft extension 28 which passes through the sleeve 16 and through a bronze bearing 29.

Between this shaft extension 28 and the drum 15 reduction gearing organization is provided 105 which consists of a pinion 30 fixed on shaft extension 28 and meshing with a large gear wheel 31 mounted on an intermediate shaft 32. The gear wheel 31 is interconnected with a shaft 32 so that as the gear wheel 31 rotates the shaft 32 110 also rotates. The motion of the shaft 32 is transmitted to two countershafts 34 by means of a. small gear Wheel 35 keyed on the shaft 32 and meshing with two larger gear wheels 36, one xed on one and the other fixed on the other of the shafts 34. The counter shafts 34 are supported in bearings V34 provided in walls 37 and 38 provided in the sections of the gear casing 9 and at one end these countershafts project into the interior of the drum and carry driving pinions 40 which mesh with an internal ring gear 41 securely fastened to one end of the drum 15. This manner of applying the drive to the drum through two pinions precludes the setting up of excessive stresses in any of the parts of the motion transmission train, makes it possible to use smaller gear elements and renders the structure far more compact than if a single pinion were used.

In the reduction gearing just described and of course interposed between the motor and the drum 15, a load brake designated generally at 45 is provided and consists of a ratchet wheel 46 mounted on a bushing 47 encircling a hub extension of the gear wheel 31. Between one face of this ratchet wheel 46 and the gear Wheel 31 a friction disc 48 is interposed. A similar friction disc 49 is interposed between the other face of the ratchet wheel 46 and a brake plate 50 is pinned to the shaft 32.

The hub of the gear wheel 31 is interiorly threaded and meshes with a screw 51 formed on the shaft 32. A pawl 52 is pivoted on the gear casing and is designed to engage with the ratchet wheel 46 to prevent movement thereof in one direction. To prevent the pawl from-clicking over the teeth of the ratchet wheel when the ratchet wheel is moved in the other direction, in which direction the drum 15 is being rotated to elevate the load block, an automatic throw out is provided for the pawl and consists of spring projected cups 53 frictionally engaging one face of the gear Wheel 3l and one face of the brake plate 50. When the drum 15 is rotated to elevate the load block the action of the screw 51 and the threads 31 of the gear wheel 31 tends to release the ratchet wheel 46. If, however, on lowering the drum 15 should overrun the motor, the screw 51 will coact with the threads of the hub of the gear wheel 31 to force the gear Wheel 31 to the right as viewed in Figure 3 whereupon the ratchet wheel 46 will be frictionally clamped between the gear 31 and the brake plate 50 and since the ratchet wheel 46 is held at this time against turning by the pawl 52 it will retard the descent of the load and prevent the same from running away.

One end of the extension 28 of the motor shaft projects through a bearing 60 in the partition 37 of the gear casing and has a brake drum 61 securely fixed thereto. Braking members 63 coact with the drum 61 as illustrated to advantage in Figure 4, these brake members being pivotally supported as at 65, and being urged to braking position'by means of springs 66 coacting with the brake members 63 and with heads or nuts 67 provided on the ends of a rod 68, the rod 68 extending through apertures 63 formed in the upper end portions of the brake members 63. For releasing the brake members and disengaging them from the drum 61 a toggle 70 is provided between the upper end portions of the brake members and the toggle may be extended to spread the brake members 63 and thereby release them by means of an operating lever 71 fulcrumed as at 72 on the gear casing, suitably interconnected with the links of the toggle, as by means of an eye-bolt 70. and connected by a yoke or link arrangement 73 with the core 74 of a solenoid 69. The solenoid 69 is so electrically connected or interlocked with the circuit for the motor that whenever the motor is turned on the solenoid is energized and the brake released whereas when the motor is turned off the solenoid is de-energized and the springs 66 function to apply the brake. A cover K completes the enclosure of the electromagnetic brake mechanism.

The motor M which is geared to the hoisting drum in the manner above described is illustrated diagrammatically in Figure 12 and has an armature 75 and field 76. The energization of the motor is under the control of a suitable switch which, as illustrated in Figures 1 and 1l, may be of the pull cord type or which as shown diagrammatically in Figure 12 may be of the push button type, the action in either event being the same.

The motor is supplied with current from power lines 77 and 78, the power line 77 having branches 79 and 80 leading to binding posts 81 and 82, respectively. The binding posts 81 and 82 are connected with contacts 83 and 84 cooperable respectively with movable contacts 85 and 86 of conventional contactors designated at C and C. The Imovable contactor blades 85 and 86 are connected by wires 87 and 88 to the opposite ends of the armature windings. One terminal of the field coil 76 is connected by a wire 89 with one terminal of the coil 75' of the solenoid 69 and the other terminal of this solenoid coil 75' is connected to the power line 78. The other terminal of the field coil 76 is connected by a. wire 90 with a binding post 91 electrically connected with the fixed contact 92 of the contactor C. Binding post 91 alsol connects by wire 93 with binding post 94 electrically connected in turn with fixed contact 95 of contactor C'.

Movable blade contacts

96 and 97 are incorporated in contactors C and C', respectively, and respectively cooperate with fixed contacts 92 and 95. The movable blade contact 96 of contactor C is electrically connected to the wire 88 and consequently to one side of the armature 75 whereas the contact 97 of contactor C is electrically connected to wire 87 and consequently to the other side of the armature windings. The

contacts

85, 86 and 96, 97 of the contactors C and C' are biased to off position but are thrown into engagement with their respective fixed contacts under the iniiuence of electromagnetic coils 99 and 98 respectively. The coil 99 has one end connected by means of a. wire 100 with binding post 81 and its other terminal is connected by a wire 101 with a fixed contact 102 of a limit switch designated generally at L. Cooperable with cona Wire 109with a contact 102 of the limit switch which is in turn electrically connected by wire 111 with the power line 78. Similarly, the contactor C' may have its

blades

86 and 97 thrown into engagement with the fixed contacts 84 and 95, respectively, when the coil 98 is energized.

The coil 98 is energized under the control of a push button switch 112 having contacts 106. 107' and 108'. Contact 106 connects by wire 110 with contact 103 of the limit switch L. Contact 103' is connected by a wire 113 with one terminal of the coil 98 and the other terminal of this coil 98 is connected by wire 114 to the binding post 82. The terminal 107' of switch 112 connects with the wire 109 and consequently with the power line 78.

When the operator presses button 108 to bridge

contacts

106 and 107 the current iiows from the power line 77 through wire 79, binding post 81, wire 100, to one terminal of the contactor coil 99, and thence from the other terminal of this coil ows through wire 101,

contacts

102, 104 and 103 of the limit switch L, through wire 105 to contact 106, and thence through

contacts

108 and 107 to wire 109. The wire 109 connects with contact 102 and consequently the current now flows through the wire 109, contact 102 and wire 111, back to the other power line 78. As a result of the completion of this circuit, contactor coil 99 is energized and the movable contacts 85 and 96 are pulled over into engagement with their respectively fixed contacts 83 and 92. This permits the current to flow from the power line 77 through wire 79, binding post 81, fixed contact 83, blade contact 85, and wire 87, to one terminal of the armature winding 75. Leaving the other terminal of the armature windings the current flows through wire 88 back to the blade contact 96 and thence passes through iixed contact 92, binding post 91 and wire 90 to one terminal of the eld 76. After flowing through the field the current passes through wire 89 over to one terminal of the brake coil 75' and after traveling through the brake coil goes back to the other power line 78. This will cause the mo tor to run forwardly, that is, in a direction to elevate the load block.

When the drum is to be reversely actuated and the load block lowered, the push button 108 is pressed inwardly to bridge

contacts

106 and 107 thereby energizing contactor coil 98 and engaging the

blade contacts

86 and 97 with their fixed contacts 84 and 95. With

contacts

86 and 97 so engaged the current ows from the power line 77, through wire and binding post 82 to fixed contact 84 and thence through the contact blade 86 to the wire 88. The wire 88 delivers the current to the opposite side of the armature from that into which the current was fed when the push button 108 was depressed thereby eiecting reverse operation of the inotor. Leaving the armature windings after entering it through the wire 88 the current passes through the wire 87 over to the contact blade 97 and thence passes up through the wire 93, contact 91 and wire 90 from whence it flows through the eld 76 and brake coil 75 as before and on back to the power line 78.

It will be noted that the maintenance of the motor circuit in either event depends upon the bridging of the

contacts

102 and 103 or 102' and 103' by the movable contacts 104 and 104', respectively, of the limit switch L. If, on the raising movement the contact 104 is disengaged from the

contacts

102 and 103 then the contactor C is de-energized and the motor Acircuit is broken. Provision is made-for carrying out this operation automatically upon `near approach of the load block to the hoisting drum and further if, after the motor circuit is interrupted in this manner, the load block continues to drift toward the hoisting drum then the contact 104' will be automatically engaged with the contacts 102 and 103' to effect a momentary reversal of the motor. Slight reverse movement of the motor under these circumstances disengages contact 104 from its cooperable contacts 102 and 103' and leaves the load block in a state of rest.

As shown to advantage in Figures 2, 7, 8, 9 and 10, the

movable contacts

104 and 104 of the limit switch L are iixed on a shaft 120 supported for rotary movement in a casing or housing 121, these

contacts

104 and 104 being angularly spaced about the shaft. The

contacts

102, 103, 102 and 103 are mounted on a fixed bracket 122 of insulating material. A coil spring 123 is interconnected with the shaft 120 and is tensioned to bias this shaft to the position shown in Figure 8, wherein the Contact 104 engages its

cooperable contacts

102 and 103. Normally, however, the shaft 120 is so positioned as to disengage contact 104 from its contact 102' and 103 and engage contact 104 with its

contacts

102 and 103 and this position of the shaft 120 is effected by means of a biasing weight 125 which has an opening through which the hoisting cable passes and which is flexibly connected by a rope or cable 126 with an arm 127, one end of whih is securelyfastened to the shaft 120. The weight acts to pull the arm 127 downwardly until its end 127 rests atly against the bottom wall of the casing 121. Referring to Figure 2, it will be seen that the load block 128 is carried by the hoisting cable 129, one side of which is secured to the hoisting drum 15 and the other end of which is dead-ended as at 129'. As vthe load block 128 closely approaches the hoisting drum it will elevate the weight 125, thereby permitting the shaft 120 to rotate in a clockwise direction as viewed in Figure 7 and consequently disengaging contact 104 'from its

contacts

102 and 103. This will de-energize the contactor C and break the motor circuit but if the block 128 continues to drift toward the hoisting drum the weight 125 will be further raised to permit the arm 127 and consequently the contact 104 to talee the position shown in Figure 8 which will result in a momentary reversal of the motor. As soon as the motor is reversed the block 128 will move away from the weight 125 sumciently to disengage contact 104 from contacts 102' and 103' whereupon the motor will again stop.

In place of the push button switch arrangement shown in Figure 12, a pull cord type of manual switch may be utilized, as illustrated to advantage in Figures 1 and 11. The pull cord type of switch includes a. rock shaft 130 supported for Arocking movement in a casing 131 which may be conveniently secured to casing 121. A double .arm lever 132 is fixed to the end of the rock shaft 130 projecting outside the casing 131 and to the outer ends of the arms of the lever are connected two pull cords 133 and 134 which have knobs or handles 133 and 134 at their lower ends. Within the casing 131 the rock shaft 130 carries .a crank arm 135 equipped with an insulating roller 136. The roller 136, when moved in one direction, exes a resilient contact 137 into engagement with a xed contact 138 and when moved in the other direction flexes a resilient I I' rod 143 supported on the casing and engaging at their inner ends a lug 145 integral with and extending radially from the hub of the crank arm 135.

The lever 132 is removably secured to its rock shaft 130 and the wall of the casing 131 adjacent; the lever is also readily detachable so that either a push button or pull cords may be employed as desired. f

The invention claimed is:

1. A hoist comprising a motor housing, a gear casing, a frame member interposed between and secured to the motor housing and gear casing, a hoisting drum between the motor housing and the gear casing, means for supporting the hoisting drum for rotation, a motor in said motor housing, a drive line actuated from the motor and extending through said means, reduction gearing in the gear casing actuated from the drive line, simultaneously acting angularly spaced pinions projecting from the gear casing into one end of the hoisting drum, pinion shafts rotatably supported on said casing, actuated from said gearing and on which said pinions are xed and an internal gear xed to the hoisting drum and meshed with said pinions and driven in either direction by the conjoint action of said pinions, said pinions meshing with said internal gear only.

2. A hoist comprising a motor housing, a gear casing, an arcuate frame member interposed between and securely fastened to the motor housing and the gear casing, said motor housing and gear casing having confronting end plates formed with inwardly directed annular iianges, a hoisting drum having its end portions rotatable within the connes of said flanges, means coacting with the hub of the drum and with the end plates of the housing and gear casing for supporting the drum for rotation, a motor in said housing, a drive line actuated by the motor and extending through said means, and reduction gearing in said gear casing and actuated from said drive line and having a driving connection with the end of the drum adjacent the end plate of the casing.

3. A hoist comprising a motor housing, a gear casing, a substantially cylindrical frame member interposed between and having its end securely fastened to the motor housing and the gear casing, said motor housing and gear casing having confronting end plates, a hoisting drum, a supporting sleeve interconnected with the hub of the drum and projecting beyond the ends of the same, bearings carried by the end plates of the motor housing and gear casing and receiving the ends of said supporting sleeve to support said sleeve and the hoisting drum for rotation, a motor in said housing, a drive line actuated by the motor and extending through said supporting sleeve and reduction gearing in said gear casing and actuated from said drive line and having a driving connection with the end of the drum adjacent the end plate of the casing.

4. A hoist comprising a motor housing, a gear casing, a substantially cylidrical frame member interposed between and having its ends securely fastened to the motor housing and the gear casing, said motor housing and gear casing having confronting end plates, a hoisting drum, a supporting sleeve interconnected with the hub of the drum and projecting beyond the ends of the same, bearings carried by the end plates of the motor housing and gear casing and receiving the ends of said supporting sleeve to support the hoisting drum for rotation, a motor in said housing, a drive line actuated by the motor and extending through said supporting sleeve and reduction gearing in said gear casing and actuated from said drive line and having a plurality of simultaneously operable driving pinions projectng through the end plate of the casing and a ring gear secured to the hoisting drum and meshed with the driving pinions, said driving pinions supplementing each other in driving the ring gear in either direction whereby a balanced drive is had.

5. A hoist comprising a motor housing, a gear casing, a frame member interposed between said motor housing and gear casing and secured thereto, a hoisting drum between the motor housing and gear casing and within the frame member, means for supporting the hoisting drum for rotation, a motor in said motor housing, a drive line actuated by the motor and extending through said means, said gear casing having an end wall and an internal partition through which the drive line extends, reduction gearing supported on said end plate and partition and actuated from the drive line, said reduction gearing having driving connection with the 'hoisting drum, and breaking means cooperable with the end portion of the drive line projecting through the partition, said partition isolating said breaking means and said reduction gearing whereby said reduction gearing may be run in an oil bath without impairing the action of the braking means.

6. A hoist comprising a motor housing, a gear casing, a frame member interposed between said motor housing and gear casing and secured thereto, a hoisting drum between the motor housing and gear casing and within the frame member, means for supporting the hoisting drum for rotation, a motor in said motor housing, a drive line actuated by the motor and extending through said means, said gear casing having an end Wall and an internal partition through which the drive line extends, reduction gearing supported on said end plate and partition and actuated from the drive line, said reduction gearing for driving connection with the hoisting drum, said reduction gearing including a load brake having a ratchet wheel adapted to have braking engagement with elements of the gearing and a pawl mounted on the gear casing and coacting with the ratchet wheel.

7. In combination with a hoist having a hoisting drum, a hoisting line actuated by the drum, a lo-ad block raised and lowered by said hoisting line and an electric motor for driving said hoisting drum, of means for limiting the approach of the the load block toward the hoisting drum and comprising a limit switch arrangement incorporated in the motor circuit, a weight having an opening through which the hoist line travels, said weight being connected to the limit switch arrangement tobias the limit switch arrangement to closed position except when engaged and lifted by the load block, and means for opening the limit switch arrangement when the load block engages the weight.

8. In combination with a hoist having a hoisting drum, a hoisting line actuated by the drum,

block and means for opening the limit switch arrangement when the weight is first engaged by the load block and for causing the limit switch arrangement to reverse the motor if the load block' thereafter continues to approach the hoisting drum.

9. In combination with a hoist having a hoisting drum, a hoisting line actuated by the drum, al load block raised and lowered by said hoisting line, and an electric motor for driving said drum,

Discnarm l,945,7l2.-Roy J. Walid, Milwaukee, Wis. Hors'r. Patent dated February .6, 1934. Disclaimer filed April 28, 1941, by the assignee, Hamischfeger Corporation.

Hereby. disclaims claim 7 in its entirety, and disclaims from the scope of claims 8 and 9 any combination with a hoist, as set forth in said claims, excepting a combination in which the means for causing the limit switch arrangement to reverse the motor are such as to become inoperative for further reverse driving'of said motor after slight reverse movement of said motor, whereby a momentary reversal only of the motor is eected to aid in bringing the parts to rest.

[Oficial Gazette May 20, 1.941.]