Apparatus for tightening threaded fasteners

The present invention seeks to protect Applicant's HYTORC® LITHIUM SERIES™ Torque Gun Tools for tightening and/or loosening of industrial threaded fasteners. Such tools include: a drive input and output assembly; a turning force multiplication assembly; a dual drive output and reaction assembly; and a yoke-style shifting assembly for any torque mode from lower and/or higher resistance and/or speed. A preferred embodiment includes an electric motor of the drive input and output assembly powered by a battery pack. Advantageously, the yoke-style shifting assembly: improves and simplifies design and operation of shifting; reduces tool size and cost; and increases tool portability, efficiency, reliability and repeatability, all without sacrificing Applicant's many innovations in hand-held, multispeed torque intensifying tools.

BACKGROUND

Threaded fasteners including bolts, studs, nuts and washers are known and used in traditional bolting applications. Maintenance and repair of industrial applications begin with loosening of and end with tightening of these threaded fasteners. Naturally industry seeks to reduce production loss during routine, unforeseen and/or emergency startup, maintenance and/or repair.

High torque values are often required for industrial bolting applications. These high torque values are often generated from relatively small, portable hydraulically, electrically and pneumatically driven tools with relatively large gear reduction ratios. These large gear reduction ratios multiply output torque from a power source of the tool through either one or a plurality of planetary gear stages. The caveat to creating high torque values from small portable tools is the driving speed is quite slow. This slow driving speed makes turning a nut for anything other than final torque arduous and time consuming. Historically, operator needed another device simply to run down and seat a nut on a stud or bolt prior to the final torqueing sequence.

Once the nut is seated on the flange surface the turning degree to tighten or loosen it up is relatively small. Customers desire high turning speeds to quickly run down or up nuts. Known impact wrenches, which provided a high run down and run off speed, had disadvantages of inaccuracy and slow rotation once the nut hit the flange face. Conversely, known handheld torque power tools were torque accurate, but relatively slow in run up and run down of fasteners. Still they were much faster than impact guns once the nut was turned on the flange face.

Applicant applied its thorough understanding and innovation in torque power tools to hand-held pneumatic torque intensifying tools, specifically by creating the HYTORC® jGUN®, HYTORC® FLIP-GUN®, HYTORC® THRILL®, HYTORC® Z®, and HYTORC® FLASH® product lines and drivers and accessories for use therewith. Evolution of these product lines and drivers and accessories for use therewith is disclosed, for example, in Applicant's U.S. Pat. Nos. and U.S. application Ser. Nos.: U.S. Pat. Nos. 6,490,952; 6,609,868; 6,929,439; 6,883,401; 6,986,298; 7,003,862; 7,066,053; 7,125,213; 7,188,552; 7,207,760; 7,735,397; 7,641,579; 7,798,038; 7,832,310; 7,950,309; 8,042,434; D608,614; Ser. Nos. 13/577,995; 15/106,221; and 15/106,247, entire copies of which are incorporated herein by reference.

Several of Applicant's tools include a higher speed/lower torque (HSLT) mode for the run up or run down of the nut and a lower speed/higher torque (LSHT) mode for the final torqueing sequence. Applicant's use of a “lock out” stage in in HSLT mode for multistage planetary gearboxes, thereby increasing rotation speed by the factor of the ratio being locked out, has proved a highly effective design. Efficient, reliable and repeatable shifting between two modes under extreme conditions during testing and in the field, however, continues to present challenges. Applicant wishes to continue improving its shifting mechanisms.

Further, Applicant's tools have been powered hydraulically, electrically, pneumatically and manually requiring an external power source which increases size and decreases portability. Tool size and portability continue to present challenges, both during development and in the field. Applicant wishes to incorporate, without sacrifice, its many innovations into a battery-operated, multi-speed, hand-held torque intensifying tool to minimize size and maximize portability.

What is needed is simplification in tool design and operation; reduction in tool size; and increased tool portability, efficiency, reliability and repeatability, all at low cost. The present invention(s) has therefore been devised to solve these issues.

Referring toFIG. 1by way of example, this shows a full perspective view of a HYTORC® LITHIUM SERIES™ Torque Gun Tool1for tightening and/or loosening of industrial threaded fasteners. Tool1includes: a drive input and output assembly100; a turning force multiplication assembly200; a dual drive output and reaction assembly300; and a yoke-style shifting assembly400for any torque mode from lower and/or higher resistance and/or speed. A preferred embodiment of tool1includes an electric motor102of drive input and output assembly powered by a battery pack105. Advantageously, yoke-style shifting assembly400: improves and simplifies design and operation of shifting; reduces tool size and cost; and increases tool portability, efficiency, reliability and repeatability, all without sacrificing Applicant's many innovations in hand-held, multispeed torque intensifying tools.

FIG. 1shows parts of drive input and output assembly100of tool1. Drive input components include drive tool housing101containing a drive generating mechanism102, handle assembly103, and a switching mechanism104. Drive generating mechanism102generates torque turning force91in one direction93to turn a nut (not shown) and is shown formed as a motor drive means which may include either a hydraulic, pneumatic, electric or manual motor. In this preferred embodiment, drive generating mechanism102is an electric motor powered by a battery pack105. Drive tool housing101is shown generally as a cylindrical body with handle assembly103which is held by an operator. Handle assembly103includes switching mechanism104for switching drive generating mechanism102between an inoperative position and an operative position, and vice-versa.

FIG. 2, by way of example, shows a cross-sectional perspective view of tool1. A turning force input shaft121connects drive input components of drive input and output assembly100with turning force multiplication assembly200and transfers turning force91between the same. A turning force output shaft122includes a driving part123, which can be formed for example as a square drive. Turning force output shaft122connects drive output components of drive input and output assembly100with turning force multiplication assembly200and transfers a multiplied form of turning force91between the same and dual drive output and reaction assembly300. In one mode of operation a reaction force spline adaptor343receives torque reaction force92in the opposite direction94. Note that turning force output shaft122and driving part123also make up portions of dual drive output and reaction assembly300. Other components shown of drive input and output assembly100include a handle rear cover electronic control panel131and related electronics.

Turning force multiplication assembly200includes turning force multiplication mechanism210portions of which are found in drive tool housing101and in a turning force multiplication mechanism housing201for all torque modes from lower resistance to higher resistance. In the embodiment shown inFIG. 2, turning force multiplication assembly200includes five (5) multiplication transmitter assemblies, or gear stages,211,212,213,214and215. Tools of the present invention may include any suitable number of gear stages. It is to be understood that there are numerous known types of turning force multiplication mechanisms. While Generally turning force multiplication transmitter assemblies211-215make up a compound epicyclic gearing system. It may include a plurality of outer planetary gears revolving about central sun gears. The planetary gears may be mounted on movable carriers which themselves may rotate relative to the sun gears. Such compound epicyclic gearing systems may include outer ring gears which mesh with the planetary gears. Simple epicyclic gearing systems have one sun, one ring, one carrier, and one planetary set. Compound planetary gearing systems may include meshed-planetary structures, stepped-planet structures, and/or multi-stage planetary structures. Compared to simple epicyclic gearing systems, compound epicyclic gearing systems have the advantages of larger reduction ratio, higher torque-to-weight ratio, and more flexible configurations.

Turning force multiplication transmitter assemblies211-215may include: gear cages; planetary gears; ring gears; sun gears; wobble gears; cycloidal gears; epicyclic gears; connectors; spacers; shifting rings; retaining rings; bushings; bearings; caps; transmission gears; transmission shafts; positioning pins; drive wheels; springs; or any combination or portion thereof. Turning force multiplication transmitters such as211-215may include other known like components as well. Note that turning force input shaft121also may be considered a turning force multiplication transmitter; specifically it's a first stage motor sun gear of turning force multiplication transmitter211. Turning force multiplication assemblies are well known and disclosed and described. An example is disclosed and described in Applicant's U.S. Pat. No. 7,950,309, an entire copy of which is incorporated herein by reference.

Referring toFIG. 3by way of example, this shows a partial perspective view of tool1in HSLT mode with emphasis on relevant portions of turning force multiplication assembly200and yoke-style shifting assembly400. One side of drive tool housing101is removed. Yoke-style shifting assembly400is substantially for shifting tool1from HSLT mode to LSHT mode and vice versa. A mode shifter switch401is movable between: a position401A which places tool1in HSLT mode; and a position401B which places tool in LSHT mode.

In the preferred embodiment shown inFIGS. 3 and 4, yoke-style shifting assembly400includes: mode shifter switch401; a shifter yoke404; and a shifter ring gear406. A shifter rod402is formed between and operatively connects mode selector switch401and shifter yoke404. A shifter clevis pin assembly403is formed between shifter rod402and shifter yoke404and a shifter yoke pin assembly405is formed between shifter yoke404and shifter ring gear406. Referring toFIG. 4by way of example, this shows a partial perspective view of tool1in LSHT mode with emphasis on relevant portions of turning force multiplication assembly200and yoke-style shifting assembly400. Again one side of drive tool housing101is removed.

Tool1operates per the following. Generally in HSLT mode, an existing planetary stage is locked out or driven though. Tool1increases rotational speed equivalent to the magnitude of the locked out gear stage ratio. Likewise tool1output torque is reduced by approximately the same magnitude. Multiplication transmitter assembly, or first stage,211, shares shifter ring gear406with yoke-style shifting assembly400.

In the embodiment shown inFIGS. 1-4, shifter ring gear406has two positions corresponding to HSLT and LSHT modes. In HSLT mode, the operator pulls shifter selector switch401toward a rear position401A. Shifter ring gear406engages an external carrier locking gear224of the same pitch and number of teeth that is part of a planetary stage carrier of first stage211. In LSHT mode, the operator pushes shifter selector switch401toward a front position401B. Shifter ring gear406engages an external mating stationary, or fixed, gear222of the same pitch and number of teeth that is grounded to drive tool housing101via a stationary ring gear adaptor223. Yoke-style shifting assembly400achieves this by transforming linear displacement of shifter rod402by mode shifter switch401to rotatably slideable displacement of shifter yoke404to linear displacement of shifter ring gear406.

Shifter ring gear406always engages with the planetary gears of first stage211, regardless of position. Stationary gear222is engaged by shifter ring gear406during LSHT mode and first stage211operates normally. Shifter ring gear406is substantially half on planetary gears of first stage211and substantially half on stationary gear222. Turning force91in one direction93leaves first stage211at a lower rate of rotation and a higher torque intensity than when it entered and is transferred to second multiplication transmitter assembly, or second stage,212. Shifter ring gear406engages external carrier gear224and locks out first stage211during HSLT mode. Shifter ring gear406is substantially half on planetary gears of first stage211and substantially half on external carrier gear224. First stage211is independently mounted on it's own bearings. First stage211is locked out in HSLT mode and spins at a substantially similar rate and intensity as drive generating mechanism102(an electric motor powered by battery pack105). A non-intensified form of turning force91in one direction93is transferred to second stage212.

The preferred embodiment of yoke-style shifting assembly400manipulates only first stage211. Generally yoke-style shifting assemblies of the present invention and modified forms thereof can shift tools into any configuration of multiplication transmitters, and therefore any torque mode from lower and/or higher resistance and/or speed. The turning force output and/or rotation speed of the motor is either increased, decreased and/or maintained by means of epicyclic gear stages or the like. They may be: stand alone components; multiplication transmitter assemblies and part of the multiplication mechanism assembly; adjacent to the motor; part of the motor; and/or or extensions of the motor. Generally yoke-style shifting assemblies of the present invention temporarily disable one and/or a plurality of such intensification and/or reduction mechanisms to increase and/or decrease the tool motor rotation speed and/or turning force intensity.

Note that tools of the present invention may include the ability to tighten and/or loosen industrial threaded fasteners by any known method, including: torque; traditional tension; mechanical tension; and/or turn of nut, or toque and angle.

A system for fastening objects includes a threaded fastener; and a torque power tool described herein. Another system for fastening objects includes a torque power tool described herein; and any novel feature or method or novel combination of features or methods described in the following commonly owned and co-pending patent applications, entire copies of which are incorporated herein by reference: Patent Cooperation Treaty Application Serial No. PCT/US2014/071000, having Filing Date of 17 Dec. 2014, entitled “APPARATUS FOR TIGHTENING THREADED FASTENERS”; Patent Cooperation Treaty Application Serial No. PCT/US2014/035375, having Filing Date of 24 Apr. 2014, entitled “APPARATUS FOR TIGHTENING THREADED FASTENERS”; U.S. Application Ser. No. 61/940,919, having Filing Date of 18 Feb. 2014, entitled “APPARATUS FOR TIGHTENING THREADED FASTENERS”; U.S. application Ser. No. 13/577,995, having Filing Date of 9 Aug. 2012, entitled “APPARATUS FOR TIGHTENING THREADED FASTENERS”; and U.S. application Ser. No. 13/113,693, having Filing Date of 23 May 2011, entitled “METHOD FOR TIGHTENING AND LOOSENING THREADED CONNECTORS”. Further, any novel feature or novel combination of features described herein with reference to and as shown in the accompanying drawings is protected.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above. The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilized for realizing the invention in diverse forms thereof. Note that there may be slight differences in descriptions of numbered components in the specification.

While the invention has been illustrated and described as embodied in a fluid operated tool, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

When used in this specification and claims, the terms “comprising”, “including”, “having” and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.