US2243642A - Drum hoist - Google Patents

Description

May 27, 1941. w. P. MUIR ET AL DRUM HOIST Filed March 28, 1939 4 Sheets-FSheet 1 ENVENTORS Wu. P. MUIR J.H.MAUDE W ATTORNEY May 27 1941. w. P. MUIR ETAL DRUM HOIST Filed March 28, 1939 4 Sheets-Sheet 2 INVENTORS YUM-P. MUIR ATETORNEY W. P. MU IR ETAL DRUM HO IS T Filed March 28, 1939 4 Sheets-Sheet 3 w. P. MUIR ET AL 7 2,243,642

May 27, 1941.

' DRUM HOISI Filed March 28, 1939 4 Sheets-Sheet 4 Patented May 27, 1941 DRUM HOIST William P. Muir, Hampstead, Quebec, and John H. Maude, Verdun, Quebec, Canada, assignors Dominion Engineering Works Limited,

Lachine, Quebec, Canada Application March 28, 1939, Serial No. 264,672

2 Claims.

This invention relates to improvements in drum hoists used in mining and other work.

The principal object is the provision of a more compact and convenient assembly of the various controls and indicating instruments which are under the care of the operator.

Another object is to provide an assembly in which the design of the lever actuated control units is such as to lend itself to the use of relatively short, conveniently grouped operating levers in place of the scattered arrangement of long, unsightly and cumbersome levers found on the operators platform of aconventional hoist.

According to this invention, the various controls and indicating instruments, which are usually scattered about the operators platform, aregrouped together and mounted in a relatively small control desk so that they are all Within convenient sight and reach of an operator seated on a chair in front of the desk.

In the preferred embodiment selected for i1- lustration, control units, such as the master control switch, emergency switch, back-out switch, and brake engine valve assembly, are mounted in compartments of the desk with their levers or other manually operable actuating elements extending upwardly through openings in the top of the desk so as to be conveniently accessible to the operator. Indicating instruments, including oil pressure gauges, depth indicator and electrical meters, are also mounted on top of the desk within convenient view of the operator.

Proceeding now to a more detailed description reference will be had to the accompanying drawings, wherein- Figure 1 is a perspective view of a portion of a drum hoist equipped with a control desk embodying my invention.

Figure 2 is a front elevation of the control desk per se. In this view portions of the front of the desk are broken away to show certain of the elements mounted therein.

Figure 3 is a vertical sectional View taken substantially along theline 3-3 of Fig, 1.

Figure 4 is a detail view of a latching means associated with the brake control lever.

Figure 5 is a vertical sectional view of a brake engine valve assembly which is mounted in the control desk in accordance with this invention.

Referring to Fig. 1, 5 designates a control desk mounted in front of a conventional hoist of the single divided drum type. Since the hoist may be of any desired or conventional design, I have shown only the drum sections 5, brakes 6, brake engines I, and operators floor 8.

The brakes 8 are of the conventional type which are applied by gravity when the fluid pressure beneath the brake releasing pistons la of the brake engine cylinder '1 is decreased by downward movement of certain brake control valves forming part of the brake valve assembly hereinafter referred to. In this connection it will be noted that each piston la is connected by piston rod lb to a cross head lc working in the cross head guide Id. Conventional operating connections 5e are provided between the guides Id and the brake shoes if.

The various control units and indicating instruments associated with the hoist are housed within or mounted on the desk 5. In this connection it will be noted that the desk is constructed to provide two end compartments 9 and I0 and a rear compartment H. The end compartments 9 and iii are closed at the top by the instrument panel 82. The inner side walls of these end compartments are spaced apart to provide an intervening space 13 which accommodates the legs of the operator when the latter is seated on a chair in front of the desk. The space I3 is closed off at the top and rear by a wall it which conceals the central portion of the rear compartment II. An upwardly projecting instrument casing I6 is located at the rear edge of panel l2. This casing is a vertical extension of compartment H and comprises relatively low end sections [8 and i9 merging with an enlarged central section 20. An ammeter 2i and a voltmeter 22 are housed in portions of sections 18 and I9 immediately adjacent the central section 29. The outer portions of sections l8 and I9 serve as housings for conventional audible signal equipment (not shown). These last mentioned portions of sections l3 and i9 are provided with front openings closed by slotted panels 23 equipped with louvers 23a overlying the slots therein.

Central section 29 of instrument casing 66 houses the depth indicator and other operating parts of a conventional Lilly Model-D controller unit 24, As here shown the depth indicator comprises a pointer 25 and a dial plate 26 located behind the window 21 of a door 28. This door closes a front opening in housing 213 and is hinged at 29. It is secured in closed position by suitable latching means 38.

When the hoist is in operation pointer 25 travels over the face of the dial plate on which the different levels or stations are indicated by the conventional tabs 3| and numerals 31a. The pointer is fixed to one end of a shaft 3!?) jour nalled in bracket 3lc which carries the governer 3|d and other parts of the Lilly controller. The other end of shaft 3Ib carries a gear 32 meshing with a gear 33 on the front end of cam shaft 34. Governor 3ld and cam shaft 34 are driven from the hoist operating mechanism by conventional gearing. As here shown, said gearing includes a worm 35 meshing with a worm wheel 36 on shaft 34. Worm 35 is mounted on a shaft 35a which extends into a gear casing 352). The casing end of shaft 35a carries a gear 35c meshing with a drive gear 35d mounted on a drive shaft 35c. Shaft 35e is driven in a well known manner from the hoist operating mechanism. The rear end of cam shaft 34 carries the usual cam plate 34a. This plate is equipped with conventional limit cams 34b and 340 for operating conventional limit switches contained in the limit switch box 31. Cam plate 34a also carries a retarding and brake regulating cam 34d which acts against a roller Me to operate the brake engine control lever 38. One end of lever 38 is pivoted to bracket 310, the remaining end being pivoted to the upper end of a connecting rod 40 working in the rear desk compartment H. The lower end of rod 40 is connected to one arm of a bell crank 4|, the other arm of which is suitably connected to operate a brake regulating cam 4 la in the event that the operator fails to retard the speed of the hoist when the retarding cam 34d reaches the roller 34c. As shown in Figs. 2, 3 and 5, the cam 4|a extends beneath the lower end of a valve rod 43 which carries a gravity applied solenoid operated emergency relief valve 43a forming part of the brake engine valve assembly generally indicated at 44. The operating solenoid of valve 43 is shown at 45 and is normally energized to hold said valve in the position shown in Fig. 5. When the solenoid 45 is deenergized the valve 43a drops to a brake applying position and, as hereinafter described, establishes fluid connections whereby the oil pressure under the brake engine pistons la is released to effect application of the brakes. The cam 4ia determines the extent to which the valve 43a is permitted to move downwardly when the solenoid 45 is deenergized and therefore regulates the speed of application of the brakes. Such cam arrangements for regulating the speed of setting the brakes are Well known in connection with conventional Lilly controller units. If the operator fails to retard the speed of the hoist when the retarding cam 34d reaches the roller 34c, further rotation of the cam plate 34a causes one of the limit cams carried thereby to open one of the limit switches in the box 31 to deenergize the solenoid 45. This method of controlling the solenoid 45 is also well known in connection with conventional Lilly control units.

The brake engine valve assembly 44 is housed in the desk compartment Ill. This assembly may be of any conventional or desire-d design. As shown in Fig. 5, it may include, in addition to the previously mentioned emergency valve 43a and solenoid 45, a manually operable valve 4! and a control cylinder 48 containing a resetting piston 49 carried by piston rod 490.. The piston 49 is normally held in the position shown in Fig. by the upper end of a spring 48a, the lower end of which rests on a spring seat 481) carried by the spring pressure regulating screw 480. The valve body 44a containing valves 43a and 41 is provided with three external pipe connections indicated at 15, 16 and I1. Pipes 15 and 16 are supply and exhaust pipes to which pipe, 11 is al- 54 at the upper end of bracket 55.

ternately connected by valve 41 which also controls communication between supply pipe and ports 48d and 48e leading to control cylinder 48. Pipe 11 is connected to the lower end of each of the brake engine cylinders I by branch pipes Ha. Valve 4'! is controlled by the manually operable brake lever 50. This lever Works in a slot 5| in the instrument panel l2 and is fixed to one end of a shaft 53 journalled in a bearing The other end of shaft 53 carries a lever arm 56 and a quadrant 51. Arm 56 is connected to valve 41 by the adjustable link 58 and floating lever 59, the latter being intermediately pivoted to the piston rod 49a of'theresetting piston working in cylinder 48.

The quadrant 51 travels between the arms 6| of a forked latch 62 provided with a stop 63. This stop is normally positioned in the path of the quadrant stops 64 and 65 and coacts therewith to determine the normal range of movement of the brake lever 50. Lever 50 is moved to the left, as viewed in Fig. 3 to apply the brakes and to the right to release the brakes.

When it is desired to lock lever 56 with the brakes fully applied, latch 62 is moved downwardly to shift stop 63 to a position below the path of the quadrant stops 64 and 65. This permits the lever to be swung through an arc sufficient to position the quadrant slot 66 directly over the latch carried stop 63. Latch 62 is then released and is raised by spring 61 so that stop 63 enters slot 66 and locks lever m its brake applying position. In the present instance latch 62 is carried by the upper end of a rod 69 which works in guide openings provided in bracket arms a and 55b projecting from bracket 55. The latch projecting spring 61 is confined between the arm 55b and a collar 16 on rod 69. The lower end of rod 69 is pivoted to a crank arm H fixed to one end of a rock shaft 12 journalled in bracket 55. The other end of rock shaft 12 extends into the space I3 between the desk compartments 9 and I0 and is equipped with a foot pedal 13. The

.15 operator depresses this pedal whenever it is desired to lower latch 62.

The following general description of the functioning of the brake valve assembly is given with the understanding that the invention contem- 50 plates the use of other types of brake engine controlvalves.

As shown in Fig. 5, the emergency relief valve 43a controls ports P P P and P Port P is connected to supply pipe 15 which is indicated 55 by dotted lines and is on the near side of said port. Pipe 11-, also shown by dotted lines, is on the far side of port P while the exhaust pipe 16, shown by dotted lines, is on the near side of exhaust port P When the solenoid 45 is energized the emergency valve 43a is in the position shown in Fig. 5 so that pipe 15 is connected through ports P and P to pipe 11 so that oil is thus supplied to the brake engine cylinders I to hold the pistons 1a in the elevated or brake releasing position shown in Fig. 1. At this time the exhaust port P is blocked by valve 4341. When the solenoid circuit is broken the emer gency relief valve 43 falls a distance determined by the position of the brake regulating cam Ma. When valve 43 drops it blocks port P and thus cuts off the supply of oil to pipe Tl. As it reaches the limit of its downward movement valve 43 reaches a position Where the exhaust port P leading from the pipe connection 11 is connected with exhaust port P so that the fluid beneath the brake engine pistons is released through pipe ll, ports I? and P and exhaust pipe 15. The drop of the emergency valve 43a is controlled by the cam did which, in turn, is regulated by the Lilly controller, thus governing the rate of emergency brake application.

The manually operable valve 41 also operates in conjunction with the three ports P, P and P In this connection it may be explained that when the manually operable brake lever is moved to raise the left hand end of the floating lever 59 the latter swings about the fulcrum afforded by its pivotal connection to the piston rod 49a of the control piston 49. The valve 47 is thus moved in a downward direction by a certain amount as prescribed by the movement of the operators hand lever. In this downward position of valve 41 the port P is placed in communication with the exhaust port 1?. In this connection it will be noted that port P is connected to the control cylinder port 48d through a small opening 48] in the diaphragm 48g so that the pressure in the upper end of control cylinder 48 is reduced. This reduction in the pressure in the upper end of control cylinder 48 permits the control piston 49 to move upwardly under the influence of the spring 48a so that the floating lever 59 is moved upwardly about the pivotal connection provided between the left hand end of the lever and the link 58. This upward movement of the floating end of the control piston cylinder 48, it will be seen that the fluid pressure on the control piston 49 is at all times essentially equal to that under the brake engine pistons la. To increase the braking effort it is necessary to decrease the fluid pressure acting on the underside of the brake engine pistons 1a and the operator accordingly moves lever 59 to the on position. If the operator holds this new position, the decreased pressure acting on the pressure control piston 49 again neutralizes the valve 4! to cut off port P from port P Conversely, should the operator desire to take the brakes off entirely or, alternately, should he wish to reduce the braking pressure, the lever 59 is swung to the right. This depresses the left hand end of floating lever 59 which swings about its pivotal connection to piston rod 49a and raises valve 47 to a position connecting ports P and P When ports P and P are thus connected fluid pressure is admitted below the brake engine pistons 7a and, at the same time, fluid pressure is delivered through ports P and 48:1 to the top of the pressure control piston 49 so as to compress the spring 48a. The left hand end of the floating lever 59 is now stationary and hence the operating valve is restored to neutral to out oil the fluid supply.

From the foregoing it will be seen that movement of lever 50 to a given position in either direction ensures a definite pressure in the brake engine cylinders.

Desk compartment I also contains a conventional back-out switch 19 which is operated by hand lever 89 working in slot 8| in control panel 12. Lever 89 swings about a pivot 82 located below panel !2 and has its lower end connected, by link 83, to the operating arm 84 of switch 19.

Other elements mounted on control panel l2 within convenientreach and sight of the operator include various tell-tale lights 86, pressure indicators 8'! and 88 and speed selector switch 89. The lights 86 are connected to indicate the operating condition of various operating and control units forming part of the complete hoist installation. Pressure indicator 8! indicates the pressure in the tank from which fluid pressure is supplied to the brake engine. Pressure indicator 88 indicates the pressures prevailing in the cylinders of the brake engines at any given time. Switch 89 enables the operator to vary the maximum speed of the hoist operating motor.

Certain conventional control switches, such as the emergency switch 9| and master switch 92, are mounted in desk compartment 9. The hand lever 93 of emergency switch 9l'extends upwardly through a slot 94 in panel I2. The hand lever 95 of master switch 92 also works in a slot 96 provided in said panel l2. The lower end of lever 95 is fixed to shaft 91 journalled in a bearing bracket 98 fastened to the inner wall of compartment 9. Shaft 91 carries an arm 99 which is connected to operating arm I of switch 92 by connecting rod l0l.

Having thus described our invention, what we claim is:

1. A hoist equipped with a control desk mounted on the operators floor, said desk comprising a top panel provided with lever slots, and compartments underlying end portions of said panel and having their inner side walls separated by an intervening space sufficient to accommodate the legs of an operator seated at the front of the desk, and lever actuated hoist control devices housed in said compartments with their operating levers extending upwardly through said slots.

2. A hoist equipped with a control desk mounted on the operators floor, said desk comprising a top panel provided with lever slots, underlying end compartments extending rearwardly from the front edge of said panel, the inner side walls of said compartments being separated by a space sufflcient to accommodate the legs of an operator seated in front of the desk, a casing projecting upwardly at the rear edge of said panel, said casing forming the upper part of a rear compartment communicating with said end compartments, lever actuated control units mounted in said end compartments with their levers extending upwardly through said slots, a Lilly control unit arranged with its component parts housed in said rear compartment, said unitincluding a depth indicator visible through an opening in the front wall of said casing.

WILLIAM P. MUIR. JOHN H, MAUDE.

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