US1238184A - Hoisting apparatus. - Google Patents

Description

A. E. NORRIS.

HOISTING APPARATUS.

APPLICATION mw SEPT. B. |911.

Patented Aug. 28, 1917.

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Patented Aug. 28, 1917.

A. E. NORRIS.

HOISTING APPARATUS.

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HOISTING APPARATUS.

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Patented Aug. 28, 1917.

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A. E. NORRIS.

HISTING APPARATUS.

APPLICATION msu SEPT. a. :9s l.

1,238, 1 84. Patented Aug. 28, 1917.

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HISTING APPARATUS.

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Patented Aug. 28, 1917.

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HOISTING APPARATUS.

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ALMON E. NORRIS, 0F CAMBRIDGE, MASSACHUSETTS.

HOISTING APPARATUS.

Specification of Letters Patent.

Patented Aug. 28, 1917.

Application filed September 8, 1911. Serial No. 648,278.

To ab' 'ur/mm t may concern:

Be it known that I, ALMoN E. Nomos, a citizen of the United States, and a resident of Cambridge, county of Middlesex, State of ltlassachusetts, whose post-ottico Iaddress is 31 Main street, Cambridgeport, Massachusetts, have invented an Improvement in Hoisting Apparatus, of which the following description, in connection with the accompanying drawings, is a specification., like characters on the drawings representinglike parts.

his invention relates to hoisting appar ratus, being more particularly concerned with the provision of suitable means for controlling the movements of load carrying devices such as clam shell buckets or the like, although as to certain oic its ieatures it is applicable to other uses.

In the following description I have dis closed one embodiment of the invention as applied to the control of a self-propelled trolley carriage equipped with a grab or bucket but my invention as to many of its features is applicable also to hoisting ap paratus equipped with other forms oi' load carrying devices and to systems employing other than self-propelled carriages.

The invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawings:

Figure l is a side elevation of a selfpropelled bucket-sustaining trolley carriage embodying one form of the invention;

Fig. 2 is a detail in elevation showing the brake for the trolley carriage;

Fig. 3 is a plan view showing the hoisting and traversing mechanism tor the trolley carriage illustrated in Fig. 1;

Fig. 4 is a section in elevation taken through the drums utilized for turning or slewing the grab;

Fig. 5 is a side elevation showing the driving gearing for the grab slewing drums;

Fig. 6 is an end elevation of the trolley carriage shown in Figs. 1 and 3;

Fig. 7 is an end elevation showing in detail the clutch for the holding drum;

Fig. 8 a sectional view of the holding drum clutch; .i

Fig. 9 is a detail in side elevation of the automatic brake for the holding drum;

Fig. 1() is a diagram of the controller connections for the hoisting motor;

Fig. 11 is a detail in side elevation oi the trolley controlling lever;

Fig. 12 is a section on a larger scale taken through the valve for the trolley brake cylinder;

Fig. 13 shows the general relation of the controlling levers;

Fig. 14 shows in sectional plan a form ot mechanical 'nterlock between the brake and clutch levers;

Fig. 15 is a detail in side elevation of the mechanical interlock shown in Fig. 1l;

Fig. 16 is a side elevation of the controlling lever for the hoisting motor;

Fig. 17 is a section taken through the controllin lever for the hoisting motor showing, m partly diagrammatic form the relation of the valves for the clutch and aumatic brake; and

Fig. 18 is an elevation partly broken away showing the elevated trackway.

Referring to the drawings and particularly to Figs. 1 to G, inclusive, the trolley carriage may be oi' any suitable construction but is herein shown as covered and partly inclosed by the casing l and provided with the truck wheels 2 on which it is mounted to run along a traekway 3. The latter is sustained by any suitable support, the same herein for the purposes of illustration being shown as provided by the coal conveyin bridge structure 4 shown in Fig. 18.

he truck wheels are driven by means of the two electric transversing motors 5, the latter being operatively connected to the trolley axles and trucks each through a driving pinion 6 and gear 7. The electric current is supplied to the carriage from any suitable source and by any of the well known devices (not herein shown), the motors herein being simultaneously controlled by means of a single controlling lever 8 (see Fig. 13) located in the operators eab 9, the latter depending from the trolley carriage between the tracks.

To provide suitable braking means for the trolley, each motor shaft is equipped with a brake drum 10 and associated brake, the latter shown in detail in Fig. 2. As there shown, the illustrated form of brake comprises the brake shoes 11 and 12 each pivoted at its lower end to the framework 1.3 of the trolley. These two shoes are normally drawn together' to clasp the drum and apply the brake by means of the spring-14. The latter is interposed between the shoe v12 and a washer fixed upon the ond of the rod 15, the o posite end of the rod being piroted to the silice 11. In the normal condition of the brake the spring draws the shoes toward each other and applies the brake holding the trolley fixed upon the trackway. To release the brake the shoes are separated by the application of fluid pressure, this being accomplished by means of the cylinder 16 containing the piston 15, the latter connected to the lever arm 17 pivoted at 18 on the shoe 1.1.. Then pressure Huid is admitted to the brake cylinder 1G the piston is depressed, the lever arm moved and the latter, through the connection 1S) to the shoe 12, spreads the slices apart. Pressure fluid is admitted to and exhausted from the Cylinder 1G by devices located at the trolley controlling lever 8 which dei ices will be subseijuently described.

Referring now to the grab or bucket 2O and the controlling devices therefor, the former may be of any suitable or ordinary construction provided with the usual jaws, the latter adapted to be opened and closed by theopening and closing rope 21, while the bucketas a whole may be held xed or lowered by means of the holding rope 22. The opening and closing rope leads upward and over a rope Winding drum 23 arranged transversely on the trolley carriage while the holding rope 22 is wound upon a similar winding drum 24 arranged parallel with the opening and closing drum.

Herein for the sake of balancing the bucket each winding drum, as shown in Fig. 3, has two rope-receiving portions and a double rope or cable is employed both for the opening and closing and the holding rope, one portion being wound upon the end portion of each Winding drum. Such feature, however, is immaterial so far as the broad features of the present invention are concerned and a single opening and closing rope and a single holding rope may be emplo ed Without distinction.

I erein the opening and closing drum 23 is ixedly secured to the driving gear 25, which latter meshes with the driving pinion 26 on the countershaft 27, the latter driven in turn by means of the electric motor 28 through the driving pinion 29 and gear 30. It therefore follows that the opening and closing drum is geared directly and at all times to the motor 28 so that when power is applied to the latter the drum is turned to Wind in the rope 21, While on the other hand hen power is shut 0H' from the motor or th latter is turned reversely the drum is turned reversely to unwind the rope, this being accompanied by the reverse movement of the motor armature.

Referring now to the holding drum 24 and particularly to Figs. 3, 7 and 8, the drum is secured to the shaft 3l and has connection with a large driving gear 33 through a clutch 32 by means of which it may be fixed to the crear or released therefrom to permit free relative movement between the gear and the drum.

The gear 33 is loose on the shaft 31 and is similar to and meshes with the gear 25 on thc opening and closing drum. Like the gear 25 it is driven from a companion electric motor 28 through the gears 29 and 30, countershaft 27 and pinion '2G so that the drum shafts are simultaneously turned by two driving motors which are controlled together as a. single unit. It is obvious however that either one of the motors alone may be used to drive the two drums.

The clutch 32 comprises a band clutch seated in a V-shaped groove, the latter formed in the drum 34 which is secured to the end of the drum 24. One end of the band (see Fig. 7) is secured to the gear 33 at 35 and the opposite end to a rock arm 36 pivoted in the face of the gear 33, the rock arm being also connected to the lever 37 so that by movement of the latter the clutch is applied or released. The clutch is normally applied to x the drum to the gear by means of the coil spring 38, connected one end to a part of the gear 33 and the other end to the lever 37. The extreme end of the lever, however, has jointed connection to a piston rod 39 attached to the piston 40 working in the pressure fluid cylinder 41 so that, when pressure fluid is admitted thereto, the piston is advanced in the cylinder moving the lever to relax the clutch against the tension of the spring.

'It will therefore be seen that the clutch 32 like the trolley brake is normally applied but may be released wholly or in part by the application of pressure fluid under the control of the operator. Pressure Huid is supplied to the cylinder 41 through the pipe 42 which latter connects with a conduit 43 formed in the hub of the gear and extending axially through the drum shaft 31. The oppositie end of the conduit has an elbow pipe connection 44 which leads to the source of supply through a controlling valve at the operators cab. Any suitable source of compressed air supply may be utilized for reeasing the trolley brake and holding drum clutch but herein an electrically driven air compressor 45 is shown in Fig. 3 secured tc the upper side of the trolley carriage.

For holding the bucket the drum 24 is preferably provided with means which automatically prevents the unwinding movement of the drum except when desired by the operator, such means being herein comprehended in the form of a brake which automatically prevents unwinding movement of the drum except when released, while permitting at all timesI the winding on movement of the drum.

While other devices may be employed for this purpose, I have herein shown the drum as having fixedly secured at the end opposite the clutch 32 a large brake wheel or drum 46 (see Fig. 9) encircled by the band brake 47, the latter being connected to a brake lever 48 and link 49 of a general construction similar to that disclosed in my copending application Serial No. 493,874, filed May 4, 1909.

Briefly described this construction provides for pivoting the brake lever 48 upon the link 49 and pivotally supporting the latter at 50 upon the fixed bracket 5l so that when the drum tends to unwind the rope by turning in the direction of the arrow shown in F ig. 9, the link, which is normally positioned by the spring 52 is drawn out toward the dotted line position shown in Fig. 9 by reason of the friction on the band. This enforced movement of the link automatically closes and applies the brake irrespective of the brake releasing lever' 48. On the other hand, rotation of the drum in the opposite direction draws the link down toward a center line passing from the axis of the drum to the pivotal support of the link, thereby automatically opening or unclasping the band and leaving the drum at all times free for rotation in that direction.

Again, the brake may be positively released for movement in the direction of the arrow by a releasing movement of the lever 48. 'lhe latter is normally held in the applied position by means of the spring 53 seated one end against the stirrup 54 carried by the releasing lever and the other end against a fixed abutment 55 carried by the fixed depending rod` 56. The brake is released by downward movement of the releasing lever caused by the admission of pressure fluid to the cylinder 57, the latter containing the piston 58 connected to the releasing lever by the rod 59. The admission of pressure fluid to the cylinder 57 is under the control of the operator in the cab as will be more fully described, so that, while th-e brake normally prevents reverse or unwinding movement of the holding drum and at all times permits the winding movement thereof, it may be released at will to permit the lowering of the grab.

Before describing in detail the controlling devices for the hoisting and trolley motors, the trolley brake, holding drum brake and holding drum clutch, reference will first be had to the mechanism for turning or slewing the grab at will, which I have herein illustrated in connection with the described form of trolley carriage.

It is frequently necessary to turn or slew the grab at will so that, while descending with the jaws open, it can be thrown with its greater dimension either lengthwise the trolley carriage or at right angles thereto.

For slewing the grab the latter has attached at diagonally opposite corners and on the upper outer edges of its jaws the two ropes or cables 60 and 61. These extend obliquely across each other and upward to the sheaves 62 and 63 respectively, which latter are carried by the trolley at diagonally opposite corners thereof. From the sheave 62 the cable 60 passes directly to the rope winding drum 64 located above the holding drum 24. From the sheave 63 the cable 61, passes upward over the sheave 65 and thence toa companion rope winding drum 66 located by the side of the drum 64 and freely rotatable therewith on the same shaft 67.

It will be seen that if the two cables 60 and 61 are held fixed relatively to the grab ropes 21 and 22 the weight of the bucket will fall upon the two turning cables and the latter being attached to diagonally opposite corners of the grab will cause the latter to be swung about to a position at right angles to that shown in Fig. l. Normally the two drums 64 and 66 are turned synchronously with the drum 24 so that the turning cables are wound on or paid out at thc same rate as the holding cable, but means are provided whereby the grab turning drums may be turned either faster or slower than the holding drum 24 and thereby caused to turn the grab.

For this purpose the two drums are connected to be driven through a balance gear connection from the drum 24. This comprises (see Fig. 4) the driving gear 68 secured to the drum 24 and meshingr with the gear 69. The latter is carried by a sleeve 70 freely rotatable about the shaft 67 but carrying also beveled gears 71 meshing with the beveled gears 72 and 7 3. The gear 72 is freely rotatable about the shaft 67 but carries fixed thereto a plate 74 on which are journaled pinions 75 meshing with an internal gear 76 formed in the end of the drum 64. The gear 75 also meshes with a small pinion 77 fixedly Secured to the shaft 67. Similar gearing connections between the drinn 66 and the beveled gear 73 are provided.

When the holding drum 24 is turned, it tends to turn the drums 64 and 66 in the same direction and at the same speed, the size of the drums and the gearing being so selected that the grab turning ropes are normally paid off or wound on at substantially the same rate as are the grab ropes. To take the turning ropes in or let them out faster than the grab ropes, however. it is only necessary to turn the shaft 67 in one direction or the other. This turns the gear 77 meshing with the gears 75 and therefore turns the latter and also the drum 64 faster or slower, as the case may be, than it would be turned by the movement of the gear 7 2 alone. A similar' action of course takes place at the drum 66.

To turn the shaft 67 an electric motor 78 is provided (see Fig. connected through the gears 79 and 80 with the countershaft 8l, the. latter being provided with the sprocket Wheel 82 by which it is connected to the shaft 67 through the chain 83 and the sprocket wheel 84. The motor 78, through which there is preferably kept a slight current at all times to provide for a slight torque'to keep the ropes taut, is controlled by appropriate controlling devices at the operators cab to be referred to later. To turn the grab, the operator has merely to start the motor in one direction or the other, thereby taking in or letting out the turir ing ropes relatively to the grab ropes. It will be observed that the balance gear between the drums 64 and 66 acts as an equalizer between the grab slewing ropes permitting the latter to play in or out Without interfering with such attendant movements as the swinging of the grab lengthwise the trackvvay in starting or stopping.

Referring to Fig. 13, the general arrangement of controlling levers for the trolley and the grab is there shown. As indicated in Fig. 1, the operator sits upon the seat 100 and faces the controlling levers, the latter comprising the lever 8 for the trolley, the lever 101 for the grab and the lever 102 for controllinvr the grab turning motor 78.

Referring first to the controlling lever 8 for the trolley the latter (see Figs. 11, 12 and 13) is connected to a suitable controller for controlling simultaneously the trolley motors 5. Such controller is conventionally indicated in outline at 103 in Fig. 13 but may be of any suitable or usual type sulficient to start, stop and reverse the trolley motors.

In order to control the trolley brakes si multaneously With th;` motor so that the brakes Will always be applied when the moA tors are at rest, but released When the motors are energized, the lower end of the trolley lever 8 (see Fig. 11) has attached thereto the cam segment 104 which controls the pressure cylinder valve for the brake cylinders 16, which valve is contained in the valve chamber 105.

VThis valve is'of such construction that pressure of any required amount may be admitted to the cylinder to relax the brake band to any desired extent so that the degree of relaxation and the freedom of the trolley from the restraint of the brake may be made directly dependent upon the posi tion of the controlling lever. ,i

Referring to Fig. 12, the eontrollinglvalve 106 is a two spool piston valve Working within the casing 105. The latter is provided with an exhaust port 107 connected to thc atmosphere and an admission port 108 connected to a suitable source of pressure fluid supply. The pipe 1.09 leading to the brake cylinders (Fig. 2) is connected With an intermediate port 110. ln addition to this there is also an auxiliary port 111.0pening into the rear end of the valve chamber and connected with the cylinder' port by a runaround passage 112 (indicated in dotted lines). At its rear end the valve is opposed by a fixed abutment 113 While its opposite end is engaged by the actuating plunger rod 114. The opposite end of the plunger rod enters one end ot the sleeve 115 which latter is mounted to slide in thc fixed block 116 and has contained within it the coiled spring 117 abutting one cnd against the plunger rod and the other end against the opposite closed end ot' the sleeve.

The valve plunger rod 111 and the sleeve 115 are located in alinement with the slide rod 11S. which latter is guided between the lixed rollers 119 and carries at its opposite end the roller 120 engaging the edge of the cam 10-1.

Then the trolley lever 8 is in its mid position cutting off the current from the motors 5, the roller 120 lies against the shallouv part of the cam and pressure is withdrawn from the spring 117. As soon aS the lever is moved, however, to start the motors either forward or backward, the plunger 11S is depressed compressing the spring 117 and thereby moving the valve 106. As soon as the valve has moved, pressure fluid passes from the port 108 to the port 110 and enters the cylinders 16 by Way of the pipe 109,` thereby releasing the brake bands.

The rear spool of the valve is exposed to an end pressure proportional to the pressure admitted to the port 110 and to the pressure cylinders 16. Such pressure therefore tends to move the valve back and, as soon as the pressure at the end of the valve exceeds the pressure of the spring, the valve Will move into its neutral position, as, for example, that shown in Fig. 12. The strength of the spring and the area of the valve are so selected that the valve will respond delicately to the pressure of the controller lever and admit and maintain a pressure supply to the cylinder1 pipe which bears a denite re lation to the position of the lever. Such pressure Will be proportionate to the ressure exerted against the spring 117 an the operator will press down against the same through the connections described With a force at all times substantially proportionate to, although it mav be considerably less than, the real pressure in the operating cylinder. In other Words this control over the brake band is under conditions Which simulate those where the band is connected directly by mechanical connections to the lever. l1' the pressure in the brake cylinder tends to rise above or fall below a point predetermined by the position of the controlling lever 8. the opposing efforts of the pressure at one end of the valve and the compressed spring at the other will act to regulate the position of the valve and correct any departure from the designed pressure.

As the controller 8 therefore is moved from its neutral position the brake is slightly relaxed, the extent of relaxation increasing as the lever reaches a more advanced position. Finally, when the lever is thrown to bring the roller 120 on the high part of the cam 10-1 the brake is wholly released and power is applied to the motors.

Referring now to the control of the bucket ropes and particularly to Figs. 1G and 17, the raising and lowering and opening and closing of the bucket is preferably controlled by the single lever 101 with the associated hand grip or latch lever 130, the lever 101 being mounted opposite and closely adjacent the trolley lever 8 (Fig. 13) so that, while the operator grasps one lever with one hand, he controls the remaining lever with the other.

The lever 101 controls the hoist motors 2S through the medium of the controller 131 represented diagrammatically in Fig. 17 the lever being fixed upon the controller sleeve shaft 132 and the latter geared to the controller through the gears 133 Iand 131. This controller, as will be more fully described, preferably has provision whereby the moAV tors may be started, stopped, reversed 0r so connected as to provide a dynamic braking effect when it is desired to lower the grab under a dynamic retardation.

' To control the automatic brake 47 for the holding drum, a valve, controlled b. the hoist lever 101, is utilized, such valve eing contained within the chamber 135. Such valve is of the same construction as. the valve 10G already described for controlling the trolley brake and its detailed construction therefore need not be repeated. The plun-I ger rod 136 for controlling the holding drum brake valve carries the cam roll 137 enga ging the sector cam 138 secured to the lower end of the hoist lever 101.

The hoist lever is thrown in the direction f indicated by the arrow in Fig. 16 to hoist the bucket and in the opposite direction to lower the same. The cam 138 therefore is so formed as to be ineffective in the hoist position of the lever, but has a raised portion which depresses the plunger 13G to re lease the holding drum brake when the lever is moved in the opposite direction for lowering. The cam is so formed, for a purpose to be referred to later, that it does not dcpress the plunger when the leyev is first thrown forward but only after passing through. an initial position does it become effective whereupon it admits pressure in a gradually increasing amount to the brake cylinder 57, gradually bringing the brake to a full release.

Referring now to the mechanism for contre-lling the holding drum clutch 32, the latch or hand grip 130 is utilized for that purpose so that the operator by squeezing the latch can release the clutch. The operator therefore is enabled to maintain control over the hoist lever and the clutch lever with a single hand, the control of the one, however in no wise interfering with the control of the other.

The latch 130 being pivoted at 139 has forked arms 1110 connected by the links 141 to the sliding block 142, the latter being con` nected to one arm of the bell crank lever 143 pivoted on a part of the hoist lever 101. The other arm of the lever 113 is jointed to the end of the slide rod 141 which passes axially through the controller sleeve shaft 132. A spring 145 normally depresses the slide block 142 but, when the latch is squeezed, the lever 143 is moved and the rod 141 projected inwardly through the actust-ing shaft 132.

The opposite end of the plunger shaft is operatively related to a controlling valve 11G contained within the chamber 1413-'L for controlling the holding drum clutch such valve being of the same construction as the valve 10G, and serving, when moved, to admit pressure fluid to the clutch cylinder 41 and maintain a deiinite pressure therein according to the position of the valve and the amount of pressure applied to the hand latch. By squeezing the latch with slight pressure the operator is enabled partly to release the clutch. By applying greater pressure thereto the clutch may be wholly released and any intermediate condition may be secured by varying the pressure applied to the latch.

In order that the holding drum may be at all times either held by the brake or operatively related to the hoisting motor through the holdingr drum clutch, and to avoid therefore the possibility of the operator drop` ping the grab by an accidental or ill-timed movement of the hand latch, the outlet pipes 150 and 151 for the clutch and brake valves respectively (see Fig. 17) do not lead directly to the clutch and brake cylinders but pass first to an interlock or safety device comprising a pressure Huid interlocking valve 152, the function of which is to prevent the release of the holding drum brake simultaneously with the release of the clutch.

Referring to Fig. 17, it will be Seen that the valve 152 is contained within the valve chamber 153 and is normally pressed against the buffer OT Stop 154 by 'the adjustable spring 155. In its depressed position the valve permits the free passage of pressure Huid from the pipe 151, which is the outlet pipe of the valve chamber 135, to the pipe 156 which is the supply pipe for the brake cylinder 57. When pressure iuid is admitted, however, by the valve 146 t0 the clutch pipe 150 such pressure fluid passes through the end of the valve chamber to the clutch supply pipe 44 and acts upon the lower end or pressure area of the valve 152 serving to lift the same against the spring 155 and shut ofi' communication between the pipes 151 and 156, thereby rendering the brake control valve ineffective to release the brake whatever be the position of the hoist lever 101 and insuring the application of the brake to the holding drum for so long as the clutch is released.

The valve chamber 153 is also provided with an outlet 157 to the atmosphere, such outlet in the raised position of the valve communicating with the pipe 156 so that in the event that the brake is already released and its cylinder filled with pressure iiuid when the clutch is released pressure Huid will escape through the outlet 157 to the atmosphere and apply the brake. The outlet may be restricted, as by the adjustable air cock 157", so that a too rapid escape of the air and therefore a too rapid application of the brake,may be prevented.

The control of the hoisting motors 28 may be effected in any desired way but, for the purpose of illustration, I have herein shown in Fig. 10 a simplified controller diagram for the hoisting motors which is sufficient to illustrate the principles of one system of control as applied to the illustrative embodiment of the invention. It will be understood that in actual practice additional elements of control, such as relay magnets, overload switches, and other devices well known in this class of apparatus, may be and preferably are employed and the controller 131 may be a master controller operating a main controlling device. Herein, however, consideration of such features is omitted for the sake of simplicity.

Referring to Fig. 10 a development of the hoist controller drum is shown at one end of which are indicated thecontroller contacts, the positive line contact being shown at 160 and the main negative at 161. The motor fields are connected to the contacts 162 and 163 and the armature to 164 and 165. Additional contacts 166 to 168, inclusive, are provided, resistance coils being interposed between the contacts 166 and 167 and 167 and 168. In the neutral or mid-position of the controlling lever 101, which position is indidicated at 0 in Fig. 10, the stationary contacts are entirely disconnected from the drum contacts and the motor circuit is ,open, the automatic brake, of course, being applied. Movement to the position a (caused y moving the lever in the direction of the arrow shown in Fig. 16) connects the motor to the feed mains but with all the resistance coils in circuit. This causes the motor to run in one direction as a motor at its slowest speed. By moving the controller to the positions o and c successive resistance coils are cut out and the speed of the hoist motor accelerated until the maximum is reached. Obviously any number of steps may be employed.

Movement of the controller lever in the opposite direction from the neutral position first brings the drum to an initial position d, the purpose of which will be later referred to, and then to positions e, f and g in succession. In the position e the fields and armatures of the motor are connected in short circuit so that while the motor may turn reversely it acts as a generator or a dynamic brake tending to retard the pull of the grab ropes and the descent of the grab. In the position c both the resistance coils are in series with the armature but in the position f one coil is cut out and in the position e all resistance is withdrawn and the braking effect is at the greatest. It will be seen that the brakingr effect and the retardation increase the farther the controller handle is moved.

It will be observed that the closed grab may he opened either when the grab is at rest or when it is being lowered by squeezing the hand latch, which action admits pressure fluid to the clutch cylinder 41 and permits the opening and closing rope to unwind pulling the motor armature around with it. It is sometimes desirable to accelerate this movement and reverse the motor to positively pay out the opening and closing rope. To provide for this condition the controller contacts are so arranged that if the controller drum be turned to the initial lowering position d, the motor will be reversed at a slow speed provided the hand latch at the same time is compressed.

This arrangement of controller contacts is employed in coperation with a circuit controlling switch actuated by the hand latch. Referring to Figs. 10 and 17, it will be seen that the plunger shaft 144 carries a contact ring 180 which, in the inactive position of the latch, is adapted to bridge the contacts 181 and 182. These contacts (see Fig. 10) are in a branch circuit which connects the motor fields with the controller contact 183. When the latch is squeezed the contact ring breaks the branch field circuit but engages with contacts 184 and 185 which are ina second branch circuit connecting the negative terminal with the controller contact 186. Except when the latch is squeezed the controller contact 186 is open. When the latch is squeezed, however, if the controller is then in or is moved to the position d, current is admitted to the motor but in a reverse direction giving a slow speed reverse.

The contact 183 constitutes the field contact in the three braking positions of the controller so that, when the latch is squeezed with the controller in any one of these three positions, while the clutch is released, the application of the brake is assured through the interlock while the lnotor is left free to allow the opening and closing rope to run out and the jaws to open.

To operate the grab slewing motor the controlling lever 102 is connected to a controller 190 diagrammatically shown in Fig. 13 through which controller the operator can start, stop or reverse thc grab slewing motor 78. This lever is located adjacent the trolley lever 8, and, the grab being turned ordinarily when the trolley is at rest, such lever can be moved by the same hand which is employed to move the trolley controlling lever.

The operation of the controlling mechanism will be evident from the preceding description. The trolley is held fast by the spring caused application of the brake shoes 11 and 12 so long as the controlling lever 8 is in its mid position. When the latter is moved in one direct-ion the trolley motors are started up and the brake is simultaneously released by pressure Huid admitted to the cylinders 16 throu h movement of the valve 10G. Movement o the lever in the opposite direction reverses the travel of the trolley and when the lever is brought to its mid position the power is shut off from the motor and the brakes simultaneously applied.

To hoist the grab the hoisting lever 101 is moved in the direction of the arrow shown in Fig. 16 the automatic brake permitting free rotation in the direction of winding on, but preventing unwinding, and remaining elfective at all times to hold the drum against reverse movement. To lower the grab the controlling lever is moved past the initial position d of the controller to the positions e f or g, while leaving the latch 130 in its normal position. This automatically releases the brake to permit lowering and at the same time connects the motor to give a dynamic braking effect greater or less according to the position of the controlling lever.

1f, during the lowering movement of the grab, it is desired to open the jaws, the hand latch 130 is squeezed, this serving to break the motor circuit at the contacts 181 and 182 and at the same time to release the holding drum clutch. The release of the clutch simultaneously applies the brake so that, with the bucket held by the brake through the holding rope, the opening and closing rope is played out, o ening the bucket jaws.

To open the ucket jaws quickly the lever may be moved to bring, the controller to the initial position d and the latch simultaneously squeezed, this serving to bridge the contacts 184 and 185 and reverse the motor, the clutch being at the same time released and the brake held applied.

With the controlling lever in its neutral position the latch may be squeezed at any time to release the clutch and open the jaws.

To sink the bucket into the coal at the same time closing the jaws thereof, the open jawed bucket may be dropped on the top of the coal with a considerable amount of slack. The lever is then thrown toward the hoisting position and the latch squeezed, which results in winding in the opening and closing rope to close the jaws while still leaving slack on the holding rope permitting the bucket to sink into the coal as the aws close. When the jaws are closed the latch is released causing both ropes to be wound in simultaneously.

While I have herein shown an interlocking device between the clutch and the automatic brake dependent upon the fluid pressure control, the same principle may be utilized under similar circumstances where the controlling levers are directly and mechanically connected to control the brake and clutch, such, for example, as are illustrated in my prior co-pending application Serial No. 494,570.

Referring to Figs. 14 and 15, I have there shown a controlling lever 250 which may be connected through the link 251 to suitable mechanical devices which serve to release the brake when the lever is moved in the direction of the arrow. By the side of the lever 250 there is provided a second lever 252 having the mechanical connection 253 for applying the friction clutch when the lever is moved in the direction of the arrow. To provide against the possibility of the simultaneous release of both the brake and clutch, the lever 250 is connected to a shaft 25-1 concentric with the axis of the lever 252, which shaft has secured to its end the arm 255, the end of which overlies an adjustable stop screw 256 on the lever 252. Vlhen the clutch lever 252 therefore is moved to release the clutch, the stop screw 256 engages the arm 255 and moves the arm together with the lever 250 to apply the brake. The same principle of inter-connection between the brake and the clutch controlling devices may therefore be employed in the case of mechanically connected controlling levers as in the case of the pressure liuid controlling devices described herein.

While I have used the term rope in referring to the various operating ropes cf the system, it is to be understood that this term is used in a generic sense and to include other iiexible power-transmission devices, such as chains, wire cables, or the like, or

other devices having like or equivalent functions.

While I have herein Shown and described one embodiment of my invention, it is to be understood that the same, as to many of its features, is applicable to hoisting apparatus and hoisting systems other than the particular one herein described. It is also to be understood that extensive deviations may be made from the details of construction and from the relative arrangement of parts Without departing from the spirit of this invention.

Claims:

1. In a hoisting apparatus, the combination with a grab of a pair of grab turning ropes connected to the grab diagonally on opposite sides of a median line therethrough, a holding drum, a holding rope, means connected to the holdingr drum for simultaneously taking in and letting' out said turning ropes With the grab rope, and means at will for taking them in or letting them out relatively to the grab rope.

2. In a hoisting apparatus, the combination with a grab of a pair of grab turning ropes connected to the grab at appropriate points to turn the same from its normal position, a holding drum, a drum for each grab turning rope, gearing connections between the holding drum and the turning rope drums for normally driving the latter at a rate proportional to the movement of the holding drum, and means for moving the turning drums independently of the holding drum.

3. In a hoisting apparatus, the combination with a grab of a grab rope, a rope Winding drum, a pair of grab turning ropes connected to the grab at appropriate points to turn the same, Winding drums for the turning ropes, a planetary transmission gearing between the grab rope Winding drum and each of the turning drums, said gearing comprising an internal gear member, a pinion meshing with the gear, a rotatable planetary member carrying the pinion and a second pinion member also meshing with said planetary pinion, said grab rope drum being connected to turn one of said three members and the turning drum being connected to another of said members, and means for independently turning the third member to move the turning drums.

4. In a hoisting apparatus, the combination with a grab of a grab rope, a rope Winding drum, a pair of grab turning ropes connected to the grab at appropriate points to turn the same, Winding drums for the turning ropes, a planetary transmission gearing between the grab rope winding drum and each of the turning drums comprising three planetary members, to Wit, an internal gear, a rotatable planetary member and a inion, an intermediate pinion carried by said lanetary member and meshing both with said internal gear member and said pinion member, a balance gear driving member between the grab drum and one of said planetary mem bers to drive normally both drums at an equal rate of speed, the turning drum being connected to another of said planetary memH bers, and means for independently turning said third planetary member.

5. In a hoisting apparatus, the combination With a grab of a grab rope, a pair of grab turning ropes connected to the grab at appropriate points to turn the same, means YFor Winding the same in and letting them out at the same rate of speed as the grab rope, a povver driven member for taking the turning ropes in relatively to the grab rope, and means for rendering said power driven member effective or ineiiective.

6. In a hoisting apparatus, the combination with a grab of a grab rope, a motor for winding in said grab rope, a pair of grab turning ropes connected to the grab at appropriatc points to turn the same, means for Winding the same in and letting them out at the same rate of speed as the grab rope, a separate motor for taking the turning ropes in relatively to the grab rope, and means for controlling the motor.

7. In a hoisting apparatus, the combination with a grab of a grab rope, a motor for winding in said rope, a pair of grab turning ropes, connected to the grab at appropriate points to turn the same, gearing means for winding the same in and letting them out together with the grab rope, and a separate motor for independently taking said turning ropes in relatively to the grab rope, and means for controlling the motor.

8. A hoisting apparatus having a grab, a grab controlling drum, a pair of grab turning drums connected to the grab to turn the latter through the action of the drums, a shaft on which they are loosely mounted, a motor to turn said shaft, each drum being provided with an internal gear, a planetary gearing member engaging the same, a pinion fast on said shaft engaging said planetary member, and a balance gear driven b v the grab drum and serving to drive in opposite directions both said planetary members.

9. In a hoisting apparatus, the combination with a grab of a grab support, an opening and closing rope, a holding rope, means for taking in and letting out said ropes, a pair of separate grab turning ropes connected to diagonally opposite points on the grab and extending across each other and upward to the grab support, means for taking in and letting out said turning ropes simultaneously with the grab ropes, and means at Will for taking in said turning ropes relatively to said grab ropes to turn the grab.

,10. In a hoisting apparatus, the c0mbne- Masas-1 tion rwith-agrab offapair offgrab operating ropes,an overhead support for the grab, a turning ropeeonnected Ito a corner of the grab-and passing obliquely to said overhead support, means for r,taking in-and letting out said turnin rope simultaneously `with said grab opera ing rope, and `means at Will for Ataking the 4 said turning-rope in or out relatively` to said operating rope.

I1. In a hoisting Vapparatusythe combinationwith -a load carrying device of a load sustaining rope for hoistingI the same, arope winding' drum, a-motor therefor, a motor controller adapted when moved in one direction to turn the motor for Winding in the rope and when turned in the opposite directionto connect the motor 'for dynamic retardation in univinding, a brake .permitting Windingon movement, means applying the brake to prevent unwinding movement, and means automatically to release the braketo permit unwinding movementwwhen the controller is moved to an unvvindinglposition.

12. In a hoisting apparatus, the combination with` a load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relative movement to operate the same, rope Winding drums for said ropes, a motor connected to turn .said drums, a clutch between the motor and holding rope drum, a motor controller adapted in oneposition to turn the motor for winding in the holding rope, in a second position to reverse the same for ositively unwindingtlhe rope and in a third) position to connect the motor for vdynamic retardation, a brake for said holding drum permitting Winding-011 movement thereof, means for -applying the brake to prevent unwinding movement, and means automatically to release the brake to permit unwinding movement when the lcontroller is moved to the third position only.

13. In a hoisting apparatus, the combination with a load carrying device, a load sustaining rope 'or hoisting the same, a rope Winding drum, a brake for said drum normally preventing unwinding movement while permitting Winding-on movement lout adapted to be released to-permit unwinding movement, a motor for turning said drum, a motor controllin r member having a hoisting position and idleposition, and a lowering position, the latter providin a dynamic brake eii'ect for the motor, an means for conjointly controlling the brake release means with the motor controlling member and .providing for the release `of the brake .in the last of the three positions only.

ll. In a hoisting apparatus, the combination of a lo-adcarrying device, a load sustaining rope for hoisting the same, a rope winding drum, a brake for said drum normally preventing yunvvinding movement Whilepermitting Winding-fon movementbut adapted to be releasedtopermit winding-on movement, a motor `orturni'ng s'aid drum, a motor control member having a hoisting position and idle position and a succession lof lowering positions, and mleans :for convyointly controlling thebrake releasing means hrough the motorcon'trol member and providingforthe gradual lrelease of thebrake in a succession of lowering positions of the motor control member.

l5. Inahoisting apparatus, Vthe combination with a load carrying device of a `pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relativemovement to operate the same, Windin drums lfor said ropes, a motor connected to drive said drums, a clutch betweenthe motor and the holdingdrum, "a brake Jfor 'said driim, brake controlling means, clutch controlling means permitting the application f Ithe clutch either simultaneously with the application ofthe brake or separately therefrom, and interlocking means between the clutch controlling and brake releasing means. K

16. In a hoisting apparatus, the combination with a load carrying device o'f a pair of ropes therefor' including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise orlovver said device and relative inovement to operate the same, Winding drums for said ropes, a motor connected to drive said drums, a elutc'h betweenthe motor and the holding nrope drum, a brake for said dr In, brake controlling means, clutch contro ling means permitting the application of the clutch either simultaneously with the application of the brake or separately therefrom, and means preventing the simultaneous release both of the clutch :ind the brake.

17. In a hoisting apparatus, the combmation with a load carrying device of a load sustainingcrope Vfor hoisting the same, a rope Windin drum, a clutch for said drum, a brake therefor, pressure Huid me'ansifor controlling the brake, pressure iluid means for separately controlling the clutch and a pressure fluid interlocking valve preventing the simultaneous release of the brake and the clutch.

18. VIn a hoisting apparatus, the combination With aload carrying device of a pair of operating ropes therefor including a Lload sustainin or holding rope and an operating rope simi ar movement of which ropesserves to raise or lower said device and relative movement to operate the same, `Winding drums -for said ropes, a motor for said drums, a controlling lever for the motor, a

brake, a clutch, means dependent on the position of the controlling lever for controlllng the brake, and means dependent on the operation of the clutch for independently controlling the brake.

19. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relative movement to operate the same, winding drums for said ropes, a driving motor therefor, a clutch and a brake for one of said drums, means for controlling the brake, means for separately controlling the clutch, and means for alltomatically applying the brake on the release of the clutch.

20. In a hoisting apparatus, the combination with a load carrying device of a pair of controlling elements, separate pressure fluid means for controlling each of said elements, a controlling valve for each of said pressure fluid means for admitting pressure fluid thereto and exhausting the same therefrom, and an interlocking valve having means controlling the pressure fluid for one of said pressure fluid means irrespective of the position of its controlling valve but dependent upon the control of pressure fluid to the remaining pressure fluid means.

21. The combination with a load carying device of a pair of ropes therefor including a holding rope and an operating rope, similar movement of which serves to raise or lower said device and relative movement to operate the same, winding drums for said ropes, connections between the drums to drive them in unison including an interposed clutch for the holding rope drum, a brake therefor, a motor to drive the drums together when said clutch is applied, brake releasing means, clutch releasing means, a controlling lever for starting and stopping the motor, means for controlling said clutch releasing means, means connected to said motor controlling lever for permitting said brake to be applied in the stop position of said lever but permitting the same to be released in the lowering position thereof, and means preventing the release of the brake simultaneousl with the release of the clutch.

22. In a hoisting apparatus, the combination with a load carrying device of a hoisting rope therefor, a rope winding. drum for said rope, a driving motor, a clutch between the motor and the drum, a brake for the drum, a brake controller, a clutch controller for the separate control of the clutch, and interlocking means to prevent the simultaneous release of both clutch and brake.

23. In a hoisting apparatus, the combination with a load carrying device of a paar of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which serves to raise or lower said device and relative movement to operate the same, Winding drums for said ropes, a driving motor for turning the drums, a brake and a clutch for the holding ro-pe drum, pressure fluid means for operating the clutch, pressure fluid means for operating the brake, pressure Huid connections for said brake and clutch operating means leading to an operators stand, separate controlling valves, controlling devices therefor at the operators stand for separately controlling the brake and clutch, and an interlocking valve through which said pressure fluid connections pass having means for controlling the brake operating pressure automatically to apply the brake when the pressure fluid is directed to release the clutch.

24. In a hoisting apparatus, the combination with a load carrying device, a traversing support for the hoisting device, a pair oil' ropes therefor including a load sustaining rope and an operating rope, similar movement of which serves to raise or lower said device and relative movement to operate the same, winding drums for said ropes, a driving motor for the traversing support, a driving motor for the windin drums, a clutch and a brake for the holding rope drum, a controlling lever at an operators stand for controlling the traversing motor and adjacent controlling lever for the drum driving motor, brake controlling means operated automatically through the movement of the control lever for the winding drum motor to control the brake cordinately with the motor movement, means on one of the motor controlling levers and within the grasp of the hand operating the same to control the application and release of the clutch, and means for so interlocking the control of the clutch and the brake that the release of the clutch insures the application of the brake.

25. In a hoisting apparatus, the combination with a load carrying device of a load sustaining rope for hoistin the same, a rope winding drum, a clutch tierefor normally applied, clutch releasing means, a driving motor for said drum, a motor controlling lever, a clutch releasing shaft passing through the pivotal axis of said lever, and means on said lever adapted to be grasped by the hand of the operator for movin said shaft simultaneously with but indepen ently of the movement of said lever.

26. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining or ho ding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relative movement to operate the same, a rope Winding drum, a clutch for said drum, pressure fluid operating means for said clutch, a driving motor for said drum, a motor controlling lever, a

imanes clutch controllingshaft passing through the pivotaliaxisof saldlever, a valve for operating said pressure fluid means actuated by said shaft, and means on said lever adapted to be grasped by the hand of the operator for moving said shaft simultaneously with but independently of the movement of said lever.

27. VIn a hoisting apparatus, the combination with a load carrying device of a hoisting rope therefor,a rope winding drum, a motor for said drum, a motor controller Jfor said motor, a controlling lever, a clutch for said drum, a controllin f device for theclutoh operable independent y ci the controlling lever, and acircuit controlling device for said motor connected to be moved simultaneously with said clutch controlling device.

Q8. In a hoisting apparatus, the combination with a load carrying device of a pair of ropestherefor including a load sustaining or holding rope and an operating rope, similar movement of which serves to raise or lower said device and relative movement to operate the same, winding drums for said ropes, and a motor for turning the drums, a clutch between the motor and one of said drums, a motor controller, a clutch operating means operating independently of said controller, and a `controller switch moved by said clutch operating means.

29. 'In a hoisting apparatus, the combination witlra load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar moven'rent of which ropes serves to raise or lower said device and relative movement to operate the same, a rope winding drum for said ropes, a motor connected to said drums, aclutch between the motor and the holding rope drum, a brake `for the holding drum, pressure Huid clutch controlling means, a valve controlling the same, pressure Huid brake controlling means, a valve therefor, a motor controlling lever also controlling one of said valves, and means associated `with the lever for separately controlling the other valve.

30. In ahoisting apparatus, thecombination with a'load carrying device of a pair of ropesftherefor including 'a load sustaining or holding rope and an operating rope, similar movement of whichropes serves to raise or lower Vsaid device and relative movement to operate the same, rope winding drums for said ropes, a motor connected to drive said drums, Va clutch normally applied between the motor and fthe `holding rope drum, an automatic brake for the holding rope drurnto-prevent unwinding movementthereof while permitting winding-on movement, pressure-iuidieontrolled, clutch-release meansto permit release of `the brake for 'unwindng movement of the holding drum .j a motor contrlling 'lev'er, `means connected with said lever forlmoving said clutch Sli release valve comprising a lever mounted on the controlling lever and adapted `to be grasped by the hand of theoperator holding the lever, a valve controlling the brake release means, and means also connected with the motor controlling lever for moving said valve.

3l. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining' or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relative movement to Operate the saine, rope winding drums 'for said ropes, a `motor '["or driving saiddrulns, a clutch between the motor and the holding rope drum, a brake for the holding rope drum, pressure Huid clutch controlling means, a valve for operating the` same, pressure fluid brake controllingmeans, and a controlling valve therefor, a motor controlling lever, means connected with the latter for moving the brake controllingl valve, and means upon the said lever adapted to be grasped by the hand of rthe operator for actuatingsaid `clutch controllingvalve.

32. in a hoisting apparatus, thecombination witha load carryingdr-ivice oi a pair of ropestherei'or including a load sustaining orholding rope and anoperating rope. similarmovement of Which ropes serves to raiseorlower said device and relative movement to operate the same, rope winding drums for said ropes, a motor for dri vingsaid drums, a brake for the holding rope drum, a clutch also for said drum, said clutch and brakebeing arranged to he sinnlitaneously applied, a brake operating lever. pressure Huid brake operating means, and a controlling valve therefor controlled b v said lever, 1p1-assure iuid operating means forsaid clutch, a controlling valvetherefor, 'andfgrasping means on 'said lever to'operate the 'said yvarve and control the clutch.

"33. 'In a hoistingapparatus, the combination with a loadcarrying device offa pair of ropes/therefor `including a load sustaining orhdlding-rope and anoperating rope, similar movement of which `ropes serves to raise or llowerlsaid device and relative movement to operate the same, `rope winding drums for said ropes, anantomatic brake for the `holding rope drum to 'prevent unwinding Vmovement thereof while permitting Winding-on movement, means for releasing thebrlake, almtor for'driving said drums, a clutch between the motorfand the holding drum, "said'clutch and brake lbeing arranged to 'be 'simultaneously applied ias required, and means adapted `to ybe grasped by the same hand of ltheoperator for controlling both the brake releasing means and the clutch releasing means.

IB4. 'n a hoistingi apparatus, -the combination witha "load carrying device'of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves tu raise or lower said device and relative movement to operate the same, rope winding drums for said ropes, a brake and a clutch for the holding rope drum, a controlling lever, and means on said lever for separately controlling said clutch and brake.

35. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining and holding rope and an operating rope similar movement of which ropes serves to raise and lower said device and relative movement to operate the same, rope winding drums for said ropes, a motor connected to drive said drums, a clutch between the motor and the holding rope drum, a controlling lever for the motor, pressure fluid means for controlling the clutch and means upon said lever arranged to apply said clutch with a varying but predetermined amount of pressure.

36. ln a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device Aand relative movement to operate the same, Winding drums for said ropes, a motor connected to drive the drum for the operating rope, a clutch between the drum for the operating rope and the drum for the holding rope, pressure fluid means controlling the clutch, a valve to control the pressure fluid means, a motor controlled lever to control the driving motor, and a grasping device on said lever connected t0 move said valve and control the clutch.

37. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of Which serves to raise or lower said device and relative movement to operate the same, Winding drums for said ropes including a drum for said holding rope, a motor for turning the drums, a brake for said holding drum normally preventing nnwinding movement while permitting winding-on movement, pressure-fluid means to control the brake, a valve for said pressure-Huid means, a motor control means con nected also to move said valve and control the brake coordinately with the control of the motor as required.

38. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustaining or holding rope and an operating rope, similar movement of which ropes serves to raise or lower said device and relative movement to operate the same, winding drums f r said ropes including a drum for said olding rope, a motor for turning the drums, a clutch to permit relative movement between the said ropes, a brake for said holding drum, a motor control lever, pressure fluid means for controlling the brake, a valve therefor, and a cam member connected to said lever for moving said valve to control said brake cordinately with the motor.

39. In a hoisting apparatus, the combination with a load carrying device of a pair of ropes therefor including a load sustain- 1ng or holding rope and an operating rope, similarI movement of Which serves to raise or lower said device and relative movement to operate the saine, Winding drums for said ropes including a drum for said holding rope, a motor for turning the drums, a brake for said holding drum normally preventing unwinding movement While permitting w1ndingon movement, means for releasing said brake to prevent unwinding movement, and motor-controlling means cordinately controlling the release of the brake as required.

40. In a hoisting apparatus, the combination with a load carrying device, a load sustaining rope for hoisting the same, a rope winding drum, a brake for said drum, a motor for turning the drum, a motor controlling lever, pressure fluid means for controlling the brake, a valve for said pressure lluid means, and a cam member connected to said lever for moving said valve to control the brake cordinately with the motor.

all. ln a hoisting apparatus, the combination with a load carrying device, of a load sustaining rope for hoisting the same, a rope winding drum, a brake for said drum normally preventing unwinding movement while permitting Winding-011 movement, but adapted to be released to permit unwinding movement, a motor for turning said drum, and means for controlling the motor which also cordinately controls the brake releasing means.

42. ln a hoisting apparatus, the combination with a load carrying device, a load sustaining rope for hoisting the same, a rope winding drum, a brake for said drum normally preventing unwinding movement while permitting winding-on movement and adapted to be released to permit unwinding movement, a motor for turning the drum, a motor controlling lever, and means for actuating said brake releasing means when the lever is moved to a lowering position.

43. In a hoisting apparatus, the combination with a load carrying device of a hoisting rope therefor, a rope Winding drum, a brake for said drum normally preventing unwinding movement While permitting winding-on movement but adapted to be released to permit unwinding movement, a motor 'For turning said drum, a motor controlling member adapted to be moved to a hoisting position for the motor or e lower- In testimony whereof, I have signed my lng position for the same, und means for naine to thls spec1icat1on,1n the presence of oonjonxtly controlling the brake releasing two snbseriblng Wltnesses.

means with the motor and adapted to release ALMON E. NORRIS. the brake in the lowering position of the YVitnesses:

motor control member While permitting its ROBERT H. KAMMLER,

a] )plicution in other positions thereof. A. WESLEY GARDNER.

Copies of this patent may be obtained for ve cents each, by addressing the "Commissioner o1.' Patenti, Washington, ID. 0.

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