VALVE STEM LIFTER

Abstract

A valve stem lifter assembly which operates to alternatively open and close a valve, includes a rotatably mounted rotary shaft having a top end axially aligned with a riser with a rigidly connected pull shaft and an opposite end axially aligned with an operator for selectively producing rotational movement of the rotary shaft and corresponding axial movement of the riser and pull shaft. The rotary shaft is rotatably connected to the riser by radius set screws positioned horizontally in the grooves of the rotary shaft. A plurality of guide shaft rods passing through the riser interconnects the riser to the valve stem lifter assembly to prevent axial separation of the riser and rotary shaft, and rotation of the riser, while permitting free relative rotation of the rotary shaft and axial movement of the riser and pull shaft.

Claims

1. A valve stem lifter for opening and closing a valve, said lifter comprising: a frame assembly with a top and bottom portion connected through a plurality of guide rods; a riser slidably mounted to one or more of said guide rods passing through said riser; a shaft with grooves that are rotatably connected to said riser; a pull rod rigidly connected to said riser that is capable of engaging a valve element used to open or close a valve, wherein said shaft has a top end that can be rotated to provide axial movement to said riser and corresponding axial movement to said pull rod rigidly connected to said riser.

2. The valve stem lifter of claim 1 further comprising an actuating means for rotating said shaft on said free end and a valve with a valve element connected to said pull rod.

3. A valve stem lifter for opening and closing a valve, said lifter comprising: a frame assembly with a top and bottom portion and connecting means for joining said top and bottom portion; a riser slidably mounted to said connecting means passing through said riser; a pull rod capable of engaging a valve element to open or close a valve; and a shaft rotatably connected to said riser by means capable of permitting rotational movement of the shaft and corresponding axial movement of said riser and said pull rod.

Description

SUMMARY OF DRAWINGS

[0016] Some embodiments of the present invention are illustrated as an example and are not limited by the figures of the accompanying drawings, which are incorporated in and constitute a part of the specification. These drawings, together with the general description of the invention given above and the detailed description of the preferred embodiments given below, serve to explain the general principles of the invention and assembly of its component parts.

[0017] FIG. 1 is a side view of an exemplary embodiment of the present invention.

[0018] FIG. 2 is an “exploded” side view of the present invention disclosed in FIG. 1.

[0019] FIGS. 3A and 3B are side views of the present invention's riser and rotary shaft components, including some cross-sections.

[0020] FIG. 4 presents a side, top and perspective view of the present invention's riser and rotary shaft components oriented in specific positions used for assembly.

[0021] FIG. 5 illustrates a view of the present invention connected to a valve actuator and valve, as would be set up for testing purposes.

[0022] Many aspects of the invention can be better understood with reference to the above referenced drawings. The elements and features shown in the drawings are not to scale, emphasis instead being placed upon clearly illustrating the principles of exemplary embodiments of the present invention. Moreover, certain dimensions may be exaggerated to help visually convey such principles. In the drawings, reference numerals designate like or corresponding, but not necessarily identical, elements throughout the several views. Other features of the present embodiments will be apparent to a person of ordinary skill in the art from the detailed description that follows.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] Referring more particularly to the drawings which are for the purpose of illustrating preferred embodiments of the invention only, and not for the purpose of limiting same:

[0024] Throughout this disclosure, components and features of the disclosed invention may be discussed with reference to more than one illustration. A particular component or feature is given the same numeral throughout this disclosure and the accompanying illustrations.

[0025] With further reference to FIGS. 1 and 2, the valve stem lifter assembly (100) generally comprises a rotary shaft (102), a flange adapter spool (104), a riser (122) and a base mounting plate (132).

[0026] The material used to form most component parts of the valve stem lifter assembly in the preferred embodiment is AISI 4140 steel, but another similar hardened metal or material that has high fatigue strength and abrasion and impact resistance could be substituted. All component parts can be manufactured using standard processes and standard equipment and tooling found in a typical state of the art machine shop, including a lathe and CNC mill.

[0027] With further reference to FIGS. 1 & 2, the rotary shaft (102) has a “squared” knob top end (102a), a transition flanged portion (102b), and an annular grooved shaft portion (102c). The knob end of the shaft (102a) is made in conformance with ISO-5211 or similar connection, and tapers to a rounded solid tubular portion that is milled to a diameter smaller than the transition flanged portion (102b). The knob end (102a) can be engaged to turn the shaft, which is slidably mounted coaxially through the hole with internal diameter in a flange adapter spool (104). A rod wiper (108) and sleeve (110) that have a diameter smaller than the inner diameter of the hole in the flange adapter spool (104), are slidably mounted coaxially before the knob end (102a) is inserted through the hole in the flange adapter spool (104). A bearing washer (112) is inserted between the sleeve (110) and the transition portion of the shaft (102b) to cushion when the flange spool adapter (104) is pressed together in final assembly against the top of the annular grooved shaft portion (102c) when the valve lifter is assembled.

[0028] With further reference to FIGS. 3 and 4, the annular grooved shaft (102c) has a helical annular groove formed around the shaft. The grooves on the annular grooved shaft portion (102c) can be milled using conventional processes by a lathe and conventional CNC mill process. The pitch of the groves on the preferred embodiment of the present invention is 4 inches with a 270-degree spin.

[0029] As illustrated in FIG. 2, a shaft load washer (114) is mounted below the bottom lip of the transition flanged portion of the rotary shaft (102b), and an O-ring (116) and bearing support flange (118) with inside diameters greater than the rotary shaft (102) are selectively pressed against flange adapter spool (104) when the valve lifter (100) is assembled.

[0030] Referring to FIGS. 1-4, the riser (122) comprises a main body with a tubular center passageway (along line AA), a threaded counterbored hole (122b) at its distal end for receiving a top external threaded portion of the pull shaft (136), and one or more hollow guide passageways (along lines CC) where the guide shaft rods (128) pass through the riser, which, along with the flange nuts (106), are used to secure and hold the lifter assembly components together and to prevent rotation of the riser. An O-ring (116) is mounted between the bottom of the flange adapter spool (104) and the top of the tubular main passageway of the riser (122). The tubular main passageway of the riser (122) has an internal diameter and is configured to accept the annular groove shaft portion of the rotary shaft (102c). The tubular center passageway further contains one or more radius set screw holes (122a) machined to accept radius set screws (124) that are used to rotatably connect the riser (122) to the grooves on the groove shaft portion of the rotary shaft (102c), as shown in FIG. 4 and described further below.

Assembly of the Valve Lifter

[0031] During assembly, with reference to FIGS. 2-4, the rotary shaft (102) is inserted and extended rotatably through the tubular center passageway of the riser (122), with a shaft load washer (114) mounted below the bottom lip of the transition flanged portion of the rotary shaft (102b) so that it fits between said bottom of the flanged portion (102b) and the top of the tubular center passageway of the riser (line AA).

[0032] A bearing washer (112) is inserted over the knob end of the shaft (102a) to rest on the top end of the transition flanged portion (102b). The sleeve (110) is inserted over the knob end of the shaft (102a) and a rod wiper (108) is fit above the sleeve on the knob end. Next the flange adapter spool with the O-ring (116) and bearing support flange (118) lined up on the bottom, is slipped over the tops of the guide rod shafts, and each of the said shafts is inserted through a respective hole (line CC) in the flange spool adapter (104).

[0033] Referring to FIG. 4, the two radius set screws (124) are screwed into the radius set screw threaded holes (122a) cut into the body of the riser (122) as is depicted along line BB (using a hexagonal shaped tool inserted into a hexagonal drive hole opening on the head of the screws (not shown)). The rotary shaft (102) is rotated along its axis shown by line AA, and aligned to the radius set screw holes (122a) to ensure the opposite sides of the grove on the rotary shaft (102) are aligned so that each radius set screw may be screwed and tightened to advance into the channel of the said grooves on the opposite sides of the shaft (180° apart) as is shown along line BB. Once this position is achieved, the screws are tightened and lockably engaged in place through locking adhesive (such as Solution 10, Medium Strength Thread Locker made by MRO Solutions, LLC) so that they will not back out without unscrewing. This ensures that the rotary shaft (102) will rotatably move in relation to being fixed to the riser (122) through the above-described placement of the radius set screws (124) in the rotary shaft's (102) groove channels.

[0034] In a preferred embodiment the radius set screws (124) are machined from black-oxide alloy steel, and include hexagonal drive hole. Exemplary sizes may be a ¾″ length with 0.625″ screw size and ⅝″-18 thread size with UNF threads.

[0035] In a preferred embodiment, during assembly, standard machine grease is injected into the riser and/or used to coat the shaft and grooves prior to the setting of the radius set screws (124) as above described.

[0036] The pull shaft (136) shown in FIG. 2 is rigidly connected to the bottom of the riser (122) along the axis depicted by line AA in FIG. 4. In a preferred embodiment, as shown in FIGS. 3A and 3B, an external threaded end of the pull shaft (136) is screwed into a threaded hole (122b) in the bottom of the riser (122).

[0037] Next, the guide shaft rods (128) with external threads formed around each end, are, respectively, screwed into threaded holes in the base mounting plate (132). An O-ring (130) is inserted on the top of the base mounting plate (132) and then the riser (122) is slipped over a selective portion of the guide rod shafts, and each of the said shafts is inserted through a respective hollow guide passageway of the riser (lines CC) in FIG. 3A, which are lined by guide shaft rod sleeves (126) as shown in FIG. 2, and so that said O-ring (130) is between the bottom of the riser (122) and the top of the base mounting plate (132).

[0038] Each of the flange nuts (106) shown in FIG. 2 are screwed on the ends of the guide rod shafts (128) extending through the top of the flange adapter spool (104) and tightened to ensure structural integrity of the valve lifter assembly (100). A dust cover pipe (120), which is tubular, may be placed over the riser and seated between the flange mounting spool (104) and base mounting plate (132) during installation. The dust cover pipe (120) may contain a lip or fasteners to allow proper seating.

Functioning of the Valve Stem Lifter

[0039] With further reference to FIG. 4, turning the knob end of the rotary shaft (102a) allows the rotary shaft (102) to move the riser (122) linearly up or down as the two radius set screws (124) travel along the spiral grooved pathway of the rotary shaft (102) in relation to the riser (122), and thereby the pull shaft (136), which is rigidly connected to the riser (122), correspondingly moves the same stroke length linearly as the riser (122). The knob end rotation may selectively extend or retract the pull shaft (136) distally from the assembled valve lifter body (100).

[0040] In one embodiment, rotational movement of the knob end of the rotary shaft (102a) may be accomplished through an electronic or hydraulic actuator controller (of the type well known in the industry) connected to the knob end (102a). Alternatively, the rotational movement may be achieved by manual turning of the knob end (102a).

[0041] Referring generally to FIGS. 2 and 5, in accordance with the ultimate use of the described invention, a valve (504) is provided which comprises a main body that defines a valve chamber having an inlet and an outlet with a valve seat located there between. Positioned in the valve chamber is a valve element having an operating stem with a free end extending therefrom.

[0042] The pull shaft (136) may be connected to the valve seat's operating stem assembly to allow it to be used to open or close the valve as described herein. When the knob end of the rotary shaft (102a) is turned to extend the pull shaft (136) linearly away from the valve stem lifter (100), the pull shaft (136) pushes the valve's stem which presses a valve disk into the valve seat (not shown) to close the valve (504) and prevents a fluid from flowing through the valve. Conversely, when the knob end of the rotary shaft (102a) is turned clockwise, the pull shaft (136) pulls to retract the valve disk from the valve seat allowing a fluid to flow through the valve. The valve stem lifter (100) can also be used with an actuator (502) to throttle the valve seat between fully closed and open positions.

[0043] Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.