US1704464A - Automatic control mechanism for drilling rigs - Google Patents

Description

March 5, 1929. DETWILER 1,704,464

AUTOMATIC CONTROL MECHANISM FOR DRILLING RIGS Filed April 13. 1927 5 Sheets-Sheet 1 A TTORN x March 5, 1929. F. M. DETWILER AUTOIATIC CONTROL MECHANISM FOR DRILLING RIGS Filed April 13, 1927 5 Sheets-Sheet 2 March 5, 1929. F. M. DETWILER AUTOIATIC CONTROL MECHANISM FOR DRILLING RIGS Filed April 13, 1927 3 Sheets-Sheet INVENTOR %l0 ud M. Uefwz'ler A TTORNE Y Patented- Mar. 5, 1929.

UNITED STATES PATENT OFFICE.

Application fled April 13, 1927. Serial No. 163,568.

My invention relates to well drilling rigs and has for it's purpose the provision of a mechanism capable of being readily applied to the standard drillingrig and operating automatically to discontinue operation of the prime mover, whether it be a steam or gas um of a second upright 32 likewise provided with a flange base 33 secured to the belt house floor. The upper ends of the uprights 30 and 32 are forme integral with a transverse tubular member 34, one end of which is provided with a disk-shaped head 35 secured to engine, immediately upon the belt becoming --a vertical partition of the belt house. A

untrained from the band wheel, or breaking of a pump rod, drill rod, wrist pin, or any other moving part of the rig which will permit racing of the prime mover and consequent injury to the rig and prime mover.

I will describe only one form of automatic control mechanism for drilling rigs, and will point out the novel features thereofin claims.

In the accompanying drawings, 7

Figure 1 is a viewshowing in side elevation one form of automatic control mechamsm in applied position to a drilling rig, the housing for the rig being shown in section;

Figure 2 is an enlarged fragmentary view showing in side elevation the drilling rig and control mechanism, the latter bein shown in a position about to be tripped to iscontinue operation of the prime mover;

Figure 3 is a vertical sectional view taken on the line 3-3 of Figure 1;

Figure 4 is a plan view of the drilling rig and mechanism shown in Figure 2 Figure 5 is a horizontal sectional view taken on the line 55 of Figure 3.

Referring specifically to the drawin I have illustrated a standard form of dri ing rig which will include a prime mover P, in the present instance a steam engine, to which steam is supplied by a pipe 15 having interposed therein a throttle valve 16 rovide'd with an operating arm 17. The engine shaft 18 is povided with a wheel 19 about which is trained a belt 20, the latter being also trained about a band wheel 21 to rotate the latter in the direction of the arrow in Figure 2. The band wheel shaft 22 carries a crankv23 rovided with awrist pin 24 which works in a slot 25 of a pitman 26 operatively connected to one end of a walking beam 27. Of course, the opposite end of the walking beam is operatively connected to the pump rod or drill rod 28 as the case may be,- which extends down into the well.-

The automatic control mechanism embodying my invention comprises, in the present instance, a tubular upright 30 having a flanged lower end 31 bolted or otherwise secured to the floor of the belt house. This upright is rigidly braced through the mediweight 36 is slidable on the'upri'ght 30 and 1S operatively connected tothe throttle valve arm 17 by a cable 37 trained over a pulley 38 secured on the upright 30. This weight 36 normall acts to swing the valve arm 17 t0 the dotted in e position shown in Figure 2, in which position the throttle valve is closed to discontinue the supply of steam'to the en e P. Normally, however, the weight 3 is latched 1n elevatedposition to prevent movement of the throttle valve to closed position by means of a latch lever 39 having a bill 40 wh ch engages within an eye41 secured to the weight 36. This lever is fulcrumed on the stem 30 and its fulcrum oint may be adjusted vertically on the standard by the rovision of a lurahty of openings 42 throng any one of w ich a pivot pin or bolt 43 may extend. The latch lever 39 is made'of two sections adjustably connected by the provision of a plurality of openings 43 and bolts 44 for the purpose of allowin the lever to be lengthened or shortened, as will be more fully described hereinafter.

As shown in Figure 5, the free end of the lever 39 is flattened and as shown in Figure 2 it is adapted to be engaged by the u per end of a bell crank lever 45 fulcrum on the pitman 26 at a point above the slot 25. Pivoted at 45 on the lever 45 is an arm 45 which depends from the lever and is adjustable to dispose its lower end in the path of movement of the wrist pin 24, dependence bein laced on friction at the pivotal mounting o tl i e arm to maintain it in the position relative to the lever 45, to which it is adjusted. The norinal position of the lever 45in which it clears the end of the lever 39 is shown in Fig. 1, and during the normal operation of the drilling rig the wrist pin 24 is at all times maintained at the lower end of. the slot 25 of the pitman 26 due to the weight of the pump or drill rod constantly acting to rock the left hand end of the walking beam 24'upwardly as viewed in Figs. 1 and 2 and hence constantly exert an upward pull upon the pitman. However, should the pump or drill rod break and thus relieve from the walking beam the load normally imposed thereon, the wrist pin 24 will be free to move upwardly in the slot 25 to engage and thus move the lever 45 to tripping position shown in Fig. 2, so that with continued rotation of the band wheel the lever will engage the latch lever 39 and elevate the latter to release the weight 36, thereby discontinuingoperation of the engine P.

The lever 45 constitutes only one means by which the latch lever 39 can be tripped to release the weight 36 and thus move the throttle valve 16 to closed position to discontinue operation of the engine P. Another means for actuating the lever 39 is a lever 47 fulcrumed in a bearing 48 secured to the standard 32 and including a lower arm 49 disposed below the upper stretch of the belt 20, and an upper arm 50 disposed beneath the lever 39. By this arrangement, it will be seen that should the belt 20 become untrained with respect to the band wheel 21 its upper stretch will fall and engage the arm 49, thus elevating the arm 50 sutticiently to trip the latch lever 39 and thereby release the weight 36. lVith falling of the weight 36, the throttle valve 16 will be moved to closed position to discontinue operation of the engine P.

Should the connection between the walking beam 27 and the band wheel shaft 22 for any reason break, the weight of the pump rod or other device which the walking beam is actuating will throw the pitman end otthe walking beam upwardly to such a height as to actuate a cable 51 connected to the walking beam and to the latch lever 39, as shown in Figure 2, to elevate the latch lever and release the weight 36, thereby effecting discontinuance in operation of the engine P. The length of this cable 51 is such that during thenormal operation of the walking beam there is suflicient slack provided in the cable to prevent tripping of the lever 39, thus preventing accidental tripping of the lever, as will be understood.

From the foregoing description, it will be manifest that I have provided an automatic control mechanism for drilling rigs which embodies verious means for effecting discontinuance in operation of the prime mover when various movable parts of the rig fail to perform their intended functions, or when the pump rod or other rod which the walking beam is actuating breaks. It will be understood that any failures in the rig mechanism will permit racing of the prime mover and any parts of the rig which remain connected with the prime mover, thus causing injury to these parts as well as the prime mover. By the provision of my automatic control mechanism, operation of the prime mover is immediately discontinued under any of these conditions, thereby preventing injury to the prime mover and the parts 01'' the rig.

By making the latch lever 39 adjustable, its free end can be positioned at the proper point to be engaged by the bell crank lever 45 when mot er.-

the latter is moved to active position against the stop 46 and irrespective of the adjustment of the wrist pin 24: with respect to the crank 23, it being understood that in the operation of drilling rigs it is necessary to change the stroke of the walking beam through an adjustment of the wrist pin on the crank. It will thus be seen that irrespective of the stroke of the pitman my control mechanism can be made to operate through an adjustment of the latch lever 39.

Although I have herein shown and described only one form of control mechanism for drilling rigs embodying my invention, it is to be understood that various changes and modifications may be made therein without departing from the spirit of the invention and the spirit and scope of the appended claims.

I claim as my invention: v

1. An automatic control mechanism for well rigs comprising a Weight adapted for operative connection to the control element of a prime mover and adapted to actuate the control element to discontinue operation of the prime mover when the weight is released, means for latching the weight in an elc ated position to prevent operation of the control element, and means adapted for operation by the pitman of the well rig for actuating the latching means to release the weight, the last means normally occupying a position in which it is ineffective to actuate the latching means, said means in this position adapted to be engaged by a wrist pin of the rig to move said means to the first mentioned position.

2. An automatic control mechanism for well rigs comprising an upright, a weight movable on the upright, a cable connected to the weight and adapted for connection to the throttle valve of an engine, a latch lever fulcrumed on the upright and normally holding the weight in elevated position to prevent actuation of the throttle valve, a bell crank lever adapted for mounting on a pitman to occupy either of two positons in one of which it does not actuate the latch lever and in the other of which it is movable by the pitman to trip the latch lever, said bell crank lever in the first mentioned position being engageable by a wrist pin to which the pitman is connected for moving the lever to the other position.

3. An automatic control mechanism for well rigs comprising a weight adapted for operative connection to the control element of a prime mover and adapted to actuate the control element to discontinue operation of the prime mover when the weight is released, means for latching the weight in an elevated position to prevent operation of the control element, actuating means for the latching means, and means for mounting the actuating means for movement to occupy an inactive posltlon, and an active position in which it actuates the latching means to release the weight.

4. An automatic control mechanism for well rigs comprising a weight adapted for operative connection to the control element of a prime mover and adapted to actuate the control element to discontinue operation of the prime mover when the weight is released, means for latching the weight in an elevated position to revent operation of the control element, an actuating means for the latching means comprising a pivoted member normally occupying a position in which it is inefi'ective to actuate the latching means and capable of being moved to a second position in which it actuates the latching means to release the weight.

5. An automatic control mechanism for well rigs compriisng an upright, a weight movable on the upright, a cable connected to the weight and adapted for connection to the throttle valve of an engine, and a latch lever fulcrumed on the upright and havin a hooked portion engaging the weight w en the lever is in one position, to hold the weight in elevated position and prevent actuation of the throttle valve, the hooked portion being disengaged from the weight when the lever is moved to another position to thereby render the weight free to gravitate and actuate the throttle valve.

6. An automatic control mechanism for well rigs comprising an upright, a weight movable on the upright, a cable connected to the weight and adapted for connection to the throttle valve of an engine, and a latch lever pivoted on the upright above the weight and having a hook depending therefrom engaging the weight when the lever is in one position, to hold the weight in elevated position and prevent actuation of the throttle valve, the hooked ortion being disengaged from the weight when the lever is moved to another position to thereby render the weight frtie to gravitate and actuate the throttle va ve.

FLOYD M. DETWILER.

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