Patent Application
20180272512
The present disclosure is directed to a torque wrench and, more particularly, to a torque wrench having a continuous rotational drive.
A torque wrench is a tool designed to exert torque on a fastener (e.g., on a bolt head or nut having specially designed inner and/or outer surfaces) to loosen or tighten the fastener. In some embodiments, the torque wrench is powered. For example, the torque wrench can be hydraulically, pneumatically, or electrically powered. In other examples, the torque wrench is manually manipulated.
Conventional torque wrenches are ratchet-type wrenches, wherein a reciprocating motion (e.g., of an internal piston) causes the fastener to rotate through a narrow angle (e.g., through about 25°/stroke of the piston). After this rotation, the ratchet must be reset (i.e. the piston must return to its starting point), before the reciprocating motion can again cause the fastener to move through another rotational segment.
Although conventional torque wrenches may be acceptable for some applications, they can also be problematic. For example, the interrupted movement of fastener rotation due to the reciprocation of the piston may result in slow fastener rotation. The reciprocating motion of the piston may also resulting in hammering within the wrench that generates undesired vibrations and is noisy. In addition, conventional torque wrenches may be useful only under particular conditions (e.g., within dry and/or clean ambient conditions) and require frequent servicing (e.g., for cleaning and to top off or replace internal lubrication).
The torque wrench of the present disclosure solves one or more of the problems set forth above and/or other problems of the prior art.
One aspect of the present disclosure is directed to a torque wrench. The torque wrench may include an input end configured to receive a torsional input, a housing, and a gear train disposed inside the housing and operatively driven by the torsional input. The torque wrench may also include a torque multiplier disposed inside the housing and connected to the gear train, and an output end operatively driven by the gear train to produce a torsional output.
Another aspect of the present disclosure is directed to another torque wrench. This torque wrench may include a positively pressurized housing, and a pinion bevel gear disposed inside the positively pressurized housing and having a shaft configured to receive a rotational input. The torque wrench may also include a crown bevel gear disposed inside the positively pressurized housing and engaged with the pinion bevel gear, and a drive fitting operatively connected to the crown bevel gear.
Another aspect of the present disclosure is directed to yet another torque wrench. This torque wrench may include an input end configured to receive a continuous rotational input in a first direction, and an output end operatively engaged with the input end. The output end may be configured to produce a continuous rotational output in a second direction substantially orthogonal to the first direction. The torque wrench may further include a housing configured to receive the input and output ends, and a valve connected to the housing and configured to pass pressurized lubrication unidirectionally into the housing.
In one embodiment, input end 12 of wrench 10 may not mate directly with the lever or motor described above. Instead, an optional engagement unit 23 may be disposed between wrench 10 and the lever or motor. Engagement unit 23 may be configured to selectively create a mechanical coupling between input end 12 and the lever or motor, for example based on a speed, pressure, flow rate, power, and/or other parameter associated with wrench 10 and/or the lever or motor. In one embodiment, the mechanical coupling of engagement unit 23 could be selectively interrupted, such that a hammering effect is created within wrench 10 that helps to loosen and/or tighten a corresponding fastener.
The torsional output at end 14 may be accessible from multiple different directions. For example, output end 14 may have a first access face (“face”) 24 and a second access face (“face”) 26. In the disclosed embodiments, faces 24 and 26 are oriented in opposition to each other and generally (e.g., within 0-10°) normal to second axis 18. Drive fitting 22 may extend through one or both of faces 24, 26, such that the bolt may be approached from either side of wrench 10. In the example of
As shown in
Gear train 28 may include at least a pinion gear 32 and a crown gear 34. Pinion gear 32 may be formed at an end of a shaft 36 that extends to engagement interface 20, and may include a plurality of teeth that engage and drive corresponding teeth of crown gear 34. In the disclosed embodiment, the teeth of pinion gear 32 and crown gear 34 are beveled, such that pinion gear 32 may rotate about axis 16 while crown gear 34 rotates about axis 18. It is contemplated that the teeth of these gears could be straight and have a conical pitch (e.g., pinion gear 32 could be a straight bevel gear), curved and have a conical pitch(e.g., pinion gear 32 could be a spiral bevel gear), or curved and have a hypoid pitch (e.g., pinion gear 32 could be a hypoid bevel gear), as desired.
Pinion gear 32 may be supported within housing 30 by way of a bearing block 38. For example, a bearing (e.g., bushing, needle bearing, roller bearing, etc.) 40 may be disposed within bearing block 38 and configured to slidingly receive shaft 36 in an axial direction and to support rotation of shaft 36. One or more seals (e.g., o-rings or gaskets) 42 and/or retainers (e.g., circlips, snaprings, etc.) 44 may be used to seal and/or retain bearing 40 and/or shaft 36 in place within housing 30.
Crown gear 34 may have teeth extending toward an outer annular periphery, and include a central opening 46 with engagement features (e.g., internal splines, cogs, gear teeth, etc.) 48 formed therein. Features 48 may be configured to engage corresponding features 49 of drive fitting 22. It is contemplated that drive fitting 22 may pass completely through crown gear 34 via opening 46 (e.g., in a dual-sided wrench configuration—shown in
A shoulder 50 may surround opening 46 at a back (i.e., non-toothed) side of crown gear 34 and function to position and support rotation of crown gear 34 within housing 30. A bushing 52 may be placed against the back side of crown gear 34 and around shoulder 50, and include a step 54 that passes through a corresponding opening within housing 30. A seal (e.g., o-rings or gaskets) 56 may be annularly sandwiched between bushing 52 and shoulder 50, and a retainer (e.g., a circlip, snapring, etc.) 58 may engage a corresponding groove in shoulder 50 to retain crown gear 34 in place.
A bushing 60 similar to bushing 52 (e.g., similarly shaped, but having a smaller diameter) may be placed around a shoulder 62 of drive fitting 22 at an opposite side of wrench 10, and include a step 64 that passes through a corresponding opening within housing 30. A seal (e.g., o-rings or gaskets) 66 may be annularly sandwiched between bushing 60 and shoulder 62.
In the example of
Housing 30 may also be an assembly of multiple components. The components of housing 30 may include among other things, first and second plates 70, 72 oriented in opposition to each other, and a shroud 74 that wraps around edges of plates 70, 72 to surround and enclose gear train 28. Each of plates 70, 72 may be generally rectangular to match a size and shape of bearing block 38 at input end 12, and generally rounded and concentric with crown gear 34 at output end 14. The openings through which bushings 52 and 60 pass may be located at a general center of the rounded portions of plates 70, 72. Any number of fasteners 76 may be used to connect shroud 74 to the edges of plates 70, 72 and/or to connect plates 70, 72 to bearing block 38.
In one embodiment, wrench 10 may be sealed from the environment at an elevated or positive pressure. For example, one or more fittings (e.g., one-way valves) 78 may be connected to housing 30 (e.g., to one or more both of plates 70, 72) and configured to admit a lubricant (e.g., grease) into housing 30 without allowing escape of the lubricant. The lubricant may be pressurized, such that external contaminates (e.g., water, air, debris, etc.) do not enter housing 30. This may allow wrench 10 to be operated in harsh conditions (e.g., under water or in contaminated environments) without undue effects. The sealed nature of wrench 10, combined with an inherent low rotational speed and temperature, may also reduce maintenance requirements. In particular, the grease may be retained inside wrench 10 for a life of wrench 10 without significant degradation (e.g., because of the clean environment inside of sealed housing 30).
As can be seen in
As shown in
In the exemplary embodiment of
The torque wrench of the present disclosure has wide application in many different industries. The disclosed torque wrench may be used anywhere that fasteners are to be loosened or tightened with high-levels of torque and/or at high speed. For example, the disclosed torque wrench may be used in the oil and gas industry to join segments of a pipeline together.
The disclosed torque wrench may be capable of reliably producing high-levels of torque. In particular, the disclosed gear train inside of the wrench may allow for efficient torque transmission with little or no backlash. In addition, when the disclosed torque wrench is equipped with the optional torque multiplier, the torque capacity may be increased. It is contemplated that many different levels of torque capacity may be available depending on the gear ratio selected for the planetary gear arrangement. Finally, because the torque multiplier may rely on a planetary gear arrangement, the overall weight and size of the torque wrench may be small (e.g., because of nesting capabilities inherent to planetary gear arrangements).
The disclosed torque wrench may be capable of continuous 360° rotation. In particular, because the disclosed torque wrench does not rely on reciprocal motion, the torque wrench may not need to be continuously reset after only short segments of angular rotation. This may result in interruption free operation, allowing for high-speed loosening or tightening operations.
The disclosed torque wrench may be versatile. Specifically, because the disclosed torque wrench may be used with any power source (e.g., electrical, hydraulic, and/or pneumatic motor) and/or manually, the torque wrench may be used anywhere, at any time, and in any situation. In addition, the dual sided nature of the disclosed torque wrench may allow a bolt to be approached by the torque wrench from multiple directions.
Finally, the disclosed torque wrench may be simple and low-cost to maintain. In particular, because the disclosed torque wrench may be sealed and pressurized, the torque wrench may not need to be opened, cleaned, and/or lubricated frequently. In addition, the sealed and pressurized nature of the disclosed torque wrench may allow for usage in locations and/or conditions (e.g., underwater and/or in contaminated environments) not heretofore possible.
It will be apparent to those skilled in the art that various modifications and variations can be made to the torque wrench of the present disclosure without departing from the scope of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the torque wrench disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.
