Title:
Derrick elevator
United States Patent 2232890


Abstract:
This invention relates to a derrick elevator. An object of the invention is to provide an elevator specially adapted for use in connection with derricks such as are commonly used in oil fields. Another object of the invention is to provide a derrick elevator whereby the derrick man may be...



Inventors:
Stillwagon, Crawford K.
Application Number:
US32797040A
Publication Date:
02/25/1941
Filing Date:
04/05/1940
Assignee:
Stillwagon, Crawford K.
Primary Class:
Other Classes:
182/148, 187/367
International Classes:
B66B9/187; E21B15/00
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Description:

This invention relates to a derrick elevator.

An object of the invention is to provide an elevator specially adapted for use in connection with derricks such as are commonly used in oil fields.

Another object of the invention is to provide a derrick elevator whereby the derrick man may be safely elevated to his place of work in the elevator and may safely descend.

The elevator is so constructed that the derrick man, in case of fire, may be quickly, easily and safely lowered to the ground surface and be protected from the fire while descending.

The invention further embodies a novel type of brake mechanism normally held inactive by the cable from which the elevator car is suspended but which will become active in case of breakage of the cable to prevent the elevator car from suddenly dropping to the ground surface and injuring the occupants of the car.

It is a further object of the invention to provide elevator equipment for a derrick which is of such construction that it may be readily dismantled when the derrick is to be moved and readily reinstalled on the derrick at a new location.

With the above and other objects in view the invention has particular relation to certain novel features of construction, operation and arrangement of parts, an example of which is given in this specification and illustrated in the accompany drawing, wherein: Figure 1 shows a side elevation of a derrick with the elevator equipment installed.

Figure 2 shows a fragmentary, side view of the cable sheaves at the top of the derrick.

Figure 3 shows a horizontal, cross-sectional view of the elevator car.

Figure 4 shows a side elevation of the elevator car framework and illustrating the brake mechanism.

Referring now more particularly to the drawing wherein like numerals of reference designate the same parts in each of the figures, the numeral I designates a conventional type of derrick as a whole having the corner legs 2, 2 connected by the horizontal cross-bars 3 which are suitably anchored to the corresponding corner legs.

At one side of the derrick there is a vertical track formed of spaced channel irons, 4, 4, the flanges of said channel irons being turned outwardly.

As clearly illustrated in Figures 1 and 4 these IS channel irons are formed in sections for convenience in erection and dismantling. As clearly illustrated in Figure 3 the channels of each section may be connected in assembled relation by means of the inner and outer cross-straps as 5, 6 which may be welded or otherwise secured to the channels. The inner cross-straps 5 extend each way beyond the channels 4 and said extended ends form means whereby the inner cross-straps may be secured to the corresponding cross-bar 3 in any suitable manner as 1i by means of U-bolts 7 as shown in Figure 3. It is obvious that the track may be thus erected a section at a time and may be dismantled by releasing the U-bolts 7.

At the upper end of the track and fixed on the transverse shaft 8 there is a sheave 9. The shaft 8 is mounted to rotate in suitable bearings 10 which are carried by the side members of the track.

Fixed on the shaft 8 there is a gear II which is in mesh with the worm 12 on the outer end of which is fixed a sheave 13.

The numeral 14 designates the skeleton framework of the elevator car. The walls of said car are preferably formed of heavy wire mesh and lined with asbestos. It is provided with a door 16 for the ingress and exit of the passengers.

The car is suspended by means of a wire line 17 one end of which is attached to the top of the car. Said wire line works over the sheave 9 and its other end carries a counterweight 18 which moves in the well 19 between the channels 4.

Secured to the inner side of the car are the upper and lower side brackets 20, 21 and rotatably mounted on these brackets are the upper and lower wheels 22, 23 which run in the channels 4.

There is the endless cable 24 which works over the sheave 13 at the top of the track and over a corresponding sheave 25 at the lower end of the track, said cable working through suitable guideways, 26, 27 provided in the elevator car.

The occupant of the car may manipulate the cable 24 in one direction so as to drive the sheave 13 in the same direction to rotate the sheave 9 correspondingly so as to elevate the car. The car will be held against downward movement by gravity by the gearing II, 12, the pitch of said gearing being such as to support the normal 5o weight of the car with the occupant therein. So when it is desired to descend the operator will manipulate said cable 24 in the other direction so as to move the car downwardly. There will, accordingly, be no danger of the sudden descent 65 of the car except in case of breakage of the line 7.

To guard against the sudden descent of the elevator car, in the event of breakage of the wire line 17, an automatic brake mechanism has been provided. It comprises a hanger 28 which is pivoted, at its upper end, on the skeleton framework of the car. Pivotally connected to the lower end of the hanger 28 there is a brake bar 29. One end of this brake bar carries an arcuate brake shoe 30 which is pivoted thereto and the upper end of the link 31 is pivotally connected to the other end of said brake bar. The lower end of the link is pivotally connected to a brake pedal pivoted to the skeleton framework of the car. It will be seen, therefore, that the brake bar 29 and the hanger 28 may swing transversely about the pivoted end of the latter.

Fixed to the brake bar 29 and extending upwardly therefrom there is an arm 33 whose upper end is overturned and has a sheave 34 mounted to rotate thereon and to normally run on the wire line 17. The arm 33 is of such length that when the sheave 34 is bearing against the wire line 17 the brake shoe 30 will be held centered between the flanges of the corresponding channel 4. The shoe, however, will be held out of contact with the wheel 22 by the pull spring which is attached at one end to the brake bar opposite the shoe 30 and at its other end to the top of the skeleton framework of the car. Should the wire line 17 break the weight of the upper end of the arm 33 will overbalance the brake bar and brake shoe and will cause said shoe 30 to move into braking contact with the wheel 22 and the lateral swinging movement of the bar 29 will permit said shoe to move laterally into contact with the opposing flange of the channel iron 4 and wedge between said flange and the wheel 22 thus increasing the braking effect. This action will be automatic. The braking effect, however, may be accentuated by the occupant of the car by pressing on the foot pedal 32.

When the car has been elevated to a point adjacent the derrickman's platform in the derrick it will remain in that position due to the balancing influence of the counterweight 18 but it should be latched in that position to prevent its being moved by manipulation of the cable 24 by someone at the ground surface so that it will always be in readiness for the derrick man to descend. Any suitable type of latch mechanism such as 36 may be mounted on the car to be engaged with, or disengaged from, a cross-strap 6 at the will of the operator of the elevator car. The drawing and description are illustrative merely, while the broad principle of the invention will be defined by the appended claims.

What I claim is: 1. Elevator equipment for a derrick, comprising a track formed of sections, attaching means for attaching the sections, in end to end relation, to the derrick to form an approximately vertical track, an elevator car having wheels movable along the track, means for elevating and lowering the car and brake means arranged to co-act with a wheel and the track to control the descent of the car.

2. Elevator equipment for a derrick, comprising a track mounted vertically on the derrick, an elevator car having wheels movable along the track, means for elevating and lowering the car, brake mechanism, mounted to swing transversely of the car and including a brake shoe positioned to wedge between a car wheel and the track when the brake mechanism is in active position and means normally holding said brake mechanism inactive.

CRAWFORD K. STILLWAGON. -:0