Assembly and tensioning device

Abstract

The present invention relates to a tensioning device configured to simultaneously tension a plurality of positioning bolts of a multi-positioning bolt tensioner and an assembly comprising the tensioning device and a power transmission assembly. The tensioning device includes one or more planetary gears that are retained within the housing and mesh, in use, with the drive gear. A ring gear surrounds and meshes with the one or more planetary gears. A plurality of spindle gears are held in the housing. Each main shaft gear is provided with a main shaft, and the main shaft is used for being connected with a corresponding positioning bolt. A spindle gear is located around the ring gear and meshes with teeth on an outer side of the ring gear. In use, the drive gear rotates the one or more planetary gears, thereby rotating the spindle gear by the ring gear, thereby tensioning the positioning bolt. The tensioning device may be manufactured compactly by overlapping the gear discs of the spindle gear and serve as a torque multiplier between the planetary gear and the spindle gear.

Description

[0001] This application is a divisional application of an application with an international application date of October 29, 2018, a Chinese national application number of 201880072385.9 (international application number PCT / US2018 / 057923), and an invention name of “Device for simultaneously applying torque to multiple locating bolts of a multi-locating bolt tensioner”. Technical Field

[0002] The present invention relates to a device for simultaneously applying torque to a plurality of locating bolts of a multi-locating bolt tensioner, and in particular to a tensioning device and an assembly comprising the tensioning device. Background Art

[0003] Multi-Joint Tensioner (MJT), for example Tensioners sold under the trademark JOINT® are typically used as drop-in replacements for hex nuts, cap nuts, bolts, etc., generally in sizes 1″ or larger. Traditional (nut-based) MJTs thread onto an existing bolt or stud, providing an efficient method of “bolting down a joint.” A typical MJT consists of three components, i) a hardened washer that provides a hardened, flat surface for the jackbolt to “push” against; ii) a nut body, typically circular, that threads onto the existing bolt or stud and initially seats against the washer in a hand-tightened manner; and iii) an annular array of jackbolts that pass through the nut body with their tips applying pressure against the washer to pre-tension the bolt or stud.

[0004] Figure 1 is a partial cross-sectional view of an exemplary nut-type MJT 10. MJT 10 includes an annular body 12. Body 12 of MJT 10 is formed with a threaded central bore 15 to accommodate a bolt, shaft, or stud. An annular array of threaded jackbolt holes 11 extends through body 12, each arranged in a circle concentric with the central bore. A corresponding jackbolt 11 extends through jackbolt holes 14 and is threadedly received therein. MJT 10 also includes a load-bearing member in the form of a hardened washer 16, against which the tips of the jackbolts 11 abut during use. Hardened washer 16 provides support against the workpiece being secured.

[0005] In use, such as Figure 2 As shown, washers 16 are placed on studs 23 and the body 12 of the MJT is screwed onto them. All of the set bolts 11 are tightened evenly and evenly using a torque wrench 13 in two to five alternating "star" paths around the set bolts so that all of the set bolts 11 are tightened incrementally so that there is no substantial imbalance in tension between them at any time.

[0006] As Figure 1As an alternative to the nut-type MJT 10, a bolt-type MJT is also known. A bolt-type MJT generally includes a body with a threaded shaft that can be used for blind threaded holes and countersunk holes. MJTs are commercially available from Superbolt, Carnegie PA. Further discussion of MJTs can be found in U.S. Patent Nos. 4,622,730, RE33,490, 4,927,305, 5,075,950, 5,083,889, and 6,112,396, which are incorporated herein by reference.

[0007] MJTs have solved some significant problems in the past. However, their use has introduced several other challenges that need to be addressed. Specifically, each MJT retaining bolt must be tightened individually. Some industrial applications require the implementation of multiple MJTs, and in such applications, tightening each retaining bolt can become time-consuming. Typically, tightening retaining bolts involves using a wrench or a handheld tool with a socket, using which each retaining bolt needs to be tightened individually.

[0008] David Rice's U.S. Patent No. 9,573,231 discloses a handheld device for simultaneously tightening multiple retaining bolts of an MJT. However, it is believed that while the device described in the '231 patent would be suitable for tightening small retaining bolts, it would be unsuitable for tightening large retaining bolts unless it were made too large to be easily carried by an operator. Furthermore, it is believed that the '231 device may not provide sufficient torque to properly tighten larger retaining bolts.

[0009] In daily use, an operator may need to tension many MJTs and carry the tensioning device between them. Therefore, it is preferred that the tensioning device is compact while still being able to evenly apply torque to the tether bolts.

[0010] Therefore, there is a need to provide an improved tensioning device that can simultaneously tension the positioning bolts of the MJT and has a compact design. Summary of the Invention

[0011] According to a first aspect of the present invention, a tensioning device is provided, which is configured to simultaneously tension multiple locating bolts of a multi-locating bolt tensioner, the tensioning device comprising:

[0012] a housing configured to accommodate a drive gear;

[0013] one or more planetary gears held within the housing for meshing with the drive gear;

[0014] a ring gear surrounding and meshing with one or more planet gears;

[0015] a plurality of main shaft gears held in the housing, the main shaft gears including a main shaft for coupling to the locating bolt, the main shaft gears being arranged around the ring gear and meshing with an outer side thereof;

[0016] Thus in use, the drive gear rotates one or more planet gears which, via the ring gear, rotate the mainshaft gear, thereby tensioning the set bolt.

[0017] In a preferred embodiment of the present invention, the planetary gears are part of a planetary gear assembly, which also includes a carrier for the gears within a housing. The planetary gears preferably each have a shaft. Preferably, the planetary gear assembly includes a base plate and a top plate, with the shafts of the planetary gears journaled between the base plate and the top plate.

[0018] Preferably, one or more support members extend between the bottom plate and the top plate. In a preferred embodiment of the present invention, one or more support members alternate between one or more planet gears. The support members may be formed with an arcuate cross-section that is complementary in shape to the peripheral portion of the planet gears.

[0019] In a preferred embodiment of the present invention, the housing is formed with a first portion and a second portion defining a space therebetween, wherein the planetary gear assembly, the ring gear, and the mainshaft gear are located within the space.

[0020] In a preferred embodiment of the present invention, the main shaft of the main shaft gear is journaled between the first and second parts of the housing, wherein an end of the main shaft extends beyond the second part of the housing.

[0021] The gear portions of adjacent main shaft gears may be axially offset such that a portion of adjacent main shaft gears may overlap, thereby reducing the angular separation between the gears. For example, the gear portions of adjacent main shaft gears may be axially offset at two or more levels.

[0022] In a preferred embodiment of the present invention, the gear portion of the main shaft gear is offset at one of three levels.

[0023] Preferably, the first portion of the housing is formed with an aperture for receiving the planetary gear assembly therein. Preferably, the second portion of the housing is formed with an internal recess for aligning with a top plate of the planetary gear assembly. The top plate of the planetary gear assembly is preferably secured to the recess of the second portion of the housing.

[0024] According to another aspect of the present invention, there is provided an assembly combining the aforementioned tensioning device with a power transmission assembly, the power transmission assembly comprising: a worm gear which can be rotated by a drive unit such as a motor; and a gear meshing with the worm gear.

[0025] Preferably, the power transfer assembly includes an output shaft coaxial with the gear and including a first end including the drive gear.

[0026] In a preferred embodiment of the present invention, the output shaft comprises a second end comprising a further drive gear, wherein the drive gear and the further drive gear are located on opposite sides of the gear.

[0027] The worm drive may be unidirectional, wherein coupling of the tensioner to the drive gear causes the spindle to rotate in a first direction, and wherein coupling of the tensioner to another drive gear at an opposite end of the output shaft causes the spindle to rotate in a second direction opposite to the first direction for tightening and loosening the set bolt, respectively.

[0028] Preferably, the power transfer assembly includes first and second opposing sides disposed on opposite sides of the gear, with the first and second ends of the drive gear extending through the first and second opposing sides.

[0029] Preferably, the first opposing side and the second opposing side are formed to align with the first portion of the housing of the tensioning device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order that the present invention may be more readily understood and put into practice, reference will now be made to the accompanying drawings which illustrate preferred embodiments of the present invention, in which:

[0031] Figure 1 is a partial cross-sectional view of an exemplary multi-joist tensioner (MJT).

[0032] Figure 2 Shown in use tightened by a torque wrench Figure 1 MJT.

[0033] Figure 3 FIG. 4 is an exploded view of a tensioning device of an MJT according to a preferred embodiment of the present invention.

[0034] Figure 4 It is a top view of the tensioning device.

[0035] Figure 5 It is a bottom view of the tensioning device.

[0036] Figure 6 is a bottom view of the tensioner with the backing plate removed.

[0037] Figure 7 This is a view of the tensioning device cut along the first plane.

[0038] Figure 8 This is a view of the tensioning device cut along the second plane.

[0039] Figure 9 The tensioner is shown with the cover removed, mounted to a power transfer unit.

[0040] Figure 10 is a cross-sectional view of a tensioner mounted to a power transmission unit. DETAILED DESCRIPTION

[0041] Figures 3 to 8 Various views of a tensioning device 200 for simultaneously tensioning a jack bolt of an MJT are included according to a preferred embodiment of the present invention.

[0042] Tensioner 200 includes a housing 202 comprising a first portion serving as a back plate 204 and a second portion serving as a cover 206, the first and second portions being fastened together to define an interior space. Back plate 204 forms a ring having a central circular aperture 208. In the presently described embodiment, the housing is shaped as a short, stubby cylinder having a longitudinal axis 221. It will be appreciated that in other embodiments, housing 202 may have a different shape.

[0043] A planetary gear assembly (PGA) 210 is coaxially positioned within the housing 202. The planetary gear assembly includes a base plate 212 and a top plate 214. Three planetary gears 216 are journaled between the base plate 212 and the top plate 214. The planetary gears are arranged at equal angles of 120 degrees around the central axis 221 of the housing. Support members 218 are secured between the base plate and the top plate and are alternately positioned between the planetary gears 216. The support members are formed with arcuate concave surfaces that complement the outer periphery of the planetary gears 216.

[0044] The cover 206 of the housing 202 is internally formed with a central circular groove 220 (at Figure 7 、 8 ) for alignment with the top plate 214 of the planetary gear assembly 210. The top plate 214 is then secured to the planetary gear assembly 210 by means of suitable bolts 229 (only in the case of Figure 4 ) is fastened to the cover so that the top plate 214 and the planetary gear assembly (PGA) 210 are fixed together with the housing 202.

[0045] Ring gear 222 surrounds planet gears 216. Ring gear 222 has teeth on its inner wall and on its outer wall. The inner wall of ring gear 222 meshes with each planet gear 216.

[0046] A plurality of mainshaft gears 224 are held equiangularly within the housing 202 and are located at a common radial distance from the axis 221. The mainshaft gears 224 are disposed around the ring gear 222 and mesh with its outer wall. Each mainshaft gear 224 includes a gear plate 224a, i.e., a plate having a toothed outer periphery, and a mainshaft 224b extending coaxially from the gear plate.

[0047] In the preferred embodiment of the invention shown herein, the spindles 224b of the spindle gears 224 are journaled between the back plate 204 and the cover 206 of the housing 202 by means of corresponding holes and bearings 223a, 225a and 223b, 225b in the base plate 208 and cover 206. The cover end of each spindle 224b extends beyond the cover 206 of the housing 202 and terminates in a square section 227 for receiving a coupling socket 226. It can be seen that the gear discs 224a of adjacent spindle gears 224 are axially offset so that adjacent gear discs overlap. The overlap of adjacent spindle gears 224 allows the angular spacing therebetween to coincide with the location of the set bolts on the intended MJT for tensioning. For example, in Figure 6 As can be seen in the figure, the gear plates 224a1, 224a2, and 224a3 of three adjacent mainshaft gears are axially offset by three levels. This is possible because the height of the ring gear 222 is approximately three times the height of each gear plate 224a, enabling each gear plate to mesh with the ring gear at one of three different levels. Depending on the number of mainshaft gears 224 that must be positioned around the tensioning unit's axis, the required number of levels can be increased or decreased.

[0048] In the presently described embodiment, the ratio of the gear diameters from each planet gear to the ring gear to each mainshaft gear results in an overall speed reduction of 2:1 from the planet gears to the mainshaft gears and a torque increase of approximately 1:2, approximately doubling the output torque.

[0049] Figure 9 The tensioner 200 is shown with the cover 206 removed, mounted to a power transfer assembly 300. The power transfer assembly 300 includes a transmission between a driver, such as an electric, pneumatic, or hydraulic motor, and the tensioner 200. Figure 10 is through Figure 9 sectional view of the tensioning device 200 in the direction indicated by the cross section BB', the tensioning device 200 is mounted to the power transmission assembly 300. Figure 10As shown, the power transmission assembly 300 includes a worm 370 meshing with a worm gear 310. A preferred worm and worm gear arrangement designed specifically for high torque transmission is discussed in International Patent Publication No. WO2016 / 141407 in the name of Nord-Lock Australia Pty Ltd, the contents of which are incorporated herein by reference. In use, the worm 370 is coupled to the connector 303 ( Figure 9 ) connected to the shaft of the motor. A drive assembly, such as a motor, is typically provided with an output shaft that includes a standard, typically square end designed to be inserted into a socket, such as connector 303, of the power transmission assembly 300.

[0050] The central worm gear 310 is journaled in the power transfer assembly housing 320 along a central drive gear axis 311. The central drive gear axis defines the longitudinal axis of the power transfer assembly 300. The power transfer assembly housing has first and second opposing sides disposed on opposite sides of the gear, through which the first and second ends of the drive gear extend. Figure 9 As can be seen in FIG, the first and second opposing sides are formed with a peripheral lip that defines a recess that is aligned with the first portion of the housing of the tensioner.

[0051] The worm gear 310 includes an outwardly extending shaft 312, the ends of which terminate in drive gears 313a and 313b. Each drive gear 313a, 313b is adapted to be coupled to the tensioning device 200. The drive gear 313a or 313b passes through a coaxial central hole 215 ( Figure 5 ) so as to mesh with the planetary gear 216.

[0052] Therefore, assuming that the worm 370 is always driven in a single direction, the tensioning device 200 is coupled to the drive gear 313a to drive the main shaft 224b and the coupling socket 226 in a first direction, thereby tightening the positioning bolt; conversely, the tensioning device 200 is coupled to the drive gear 313b to drive the main shaft in a second direction, thereby loosening the positioning bolt.

[0053] In use, to tighten the MJT's retaining bolts, the tensioner 200 is first mounted on the power transmission assembly 300 so that the drive gear 313a is inserted into the tensioner and meshes with each of the three planetary gears 216. The main shaft 224b of the tensioner 200 is then aligned with the MJT's retaining bolts and coupled thereto via the coupling socket 226. A power source, such as an electric or pneumatic motor, is then coupled to the input socket 303 of the power transmission assembly 300. Operation of the power source rotates the worm 370, and thus the worm gear 310 of the power transmission assembly 300, thereby rotating the drive gear 313a. Consequently, each planetary gear 216 rotates, thereby rotating the ring gear 222. The rotation of the ring gear 222, in turn, causes each main shaft gear 224 to rotate. As the main shaft gear 224 rotates causing its main shaft 224b to rotate, the attached connection socket 226 also rotates, thereby applying torque to each of the set bolts of the MJT, causing them to rotate and tighten.

[0054] When it is desired to loosen the MJT's set bolts, a similar process is performed, except that the tensioner 200 is connected to the opposite side of the power transfer assembly 300. In this configuration, the drive gear 313b (opposite 313a) meshes with each of the planetary gears 216, causing rotation in the opposite direction of the mainshaft gear and loosening the set bolts.

[0055] If necessary, such as for maintenance, once top plate 214 has been released from cover 206, planetary gear assembly 210 can be removed through bottom plate 208. The planetary gear assembly can then be quickly replaced with a functional unit without having to disassemble the entire unit. Ring gear 222 is held in place by meshing with mainshaft gear 224 and planetary gears 216. The components inside housing 202 are filled with grease for lubrication.

[0056] While the particular embodiment of the invention described herein has eleven mainshaft gears and is therefore specifically designed to secure an MJT having eleven locating bolts, it will be appreciated that variations of the invention are possible having fewer or more mainshaft gears to accommodate MJTs having fewer or greater numbers of locating bolts.

[0057] All documents cited herein are incorporated by reference, but only to the extent the incorporated material does not conflict with existing definitions, statements, or other documents set forth herein.

[0058] To the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to the term in this document shall govern. The citation of any document shall not be construed as an admission that it is prior art to the present application.

[0059] In accordance with the statute, the present invention has been described in language that is more or less specific to structural or methodological features. The term "comprises" and variations thereof, such as "comprising" and "comprised of," are used throughout this document to include, but not to exclude, any additional features. It should be understood that the invention is not limited to the specific features shown or described, as the methods described herein include preferred forms of implementing the invention. The invention is therefore claimed in any form or modification thereof within the proper scope of the appended claims as appropriately interpreted by one skilled in the art.

[0060] While specific embodiments have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications may be made without departing from the spirit and scope of the invention. Those skilled in the art will recognize or be able to ascertain, by no more than routine experimentation, many equivalents to the specific apparatus and methods described herein, including substitutions, variations, additions, deletions, modifications, and alternatives. Therefore, the present application, including the appended claims, is intended to cover all such changes and modifications within the scope of this application.

Claims

1. An assembly comprising: a tensioning device configured to simultaneously tension multiple locating bolts of a multi-locating bolt tensioner; as well as a power transmission assembly comprising a worm gear drive rotatable by a motor and a gear meshing with the worm gear drive, wherein the power transmission assembly further comprises an output shaft coaxial with the gear and comprising a first end comprising a first drive gear, wherein the output shaft comprises a second end comprising a second drive gear, wherein the first drive gear and the second drive gear are located on opposite sides of the gear; Wherein, the tensioning device comprises: a housing adapted to accommodate the first drive gear; one or more planetary gears retained within the housing and adapted to mesh with the first drive gear; a ring gear surrounding and meshing with the one or more planet gears; and a plurality of main shaft gears held in the housing, the main shaft gears including a main shaft adapted to be coupled to the retaining bolt, the main shaft gears being disposed about the ring gear and meshing with an outer side of the ring gear; Whereby in use, the first drive gear rotates the one or more planet gears and thereby the mainshaft gear via the ring gear to tighten the set bolt, wherein the worm drive is unidirectional, and wherein coupling of the tensioning device to the first drive gear causes rotation of the main shaft in a first direction, and wherein coupling of the tensioning device to the second drive gear causes rotation of the main shaft in a second direction opposite to the first direction; and The power transmission assembly has a first opposite side and a second opposite side disposed on opposite sides of the gear, and the first drive gear and the second drive gear extend through the first opposite side and the second opposite side.

2. The assembly according to claim 1, wherein The planetary gear is part of a planetary gear assembly, which also includes a carrier located within the housing.

3. The assembly according to claim 2, wherein The planetary gear assembly includes a bottom plate and a top plate, and the shafts of the planetary gears are connected between the bottom plate and the top plate through shaft journals.

4. The assembly according to claim 3, wherein One or more supports extend between the bottom plate and the top plate and are located between the one or more planet gears.

5. The assembly according to claim 4, wherein The support member is formed with an arcuate cross-section having a shape complementary to a peripheral portion of the planetary gear.

6. The assembly according to claim 3, wherein: The housing is formed with a first portion and a second portion, the first portion and the second portion defining a space therebetween, and the planetary gear assembly, the ring gear, and the mainshaft gear are positioned within the space.

7. The assembly according to claim 6, wherein The main shaft of the main shaft gear is connected between the first part and the second part of the housing through a shaft journal.

8. The assembly of claim 1, wherein: Adjacent mainshaft gears are axially offset, with adjacent mainshaft gears partially overlapping to reduce the angular spacing between the gears.

9. The assembly according to claim 8, wherein The gear portion of the main shaft gear is offset in the axial direction at one of three levels.

10. The assembly according to claim 6, wherein The first portion is formed with a bore for receiving the planetary gear assembly therein.

11. The assembly according to claim 10, wherein The second portion is formed with an internal groove for alignment with a top plate of the planetary gear assembly.

12. The assembly according to claim 1, wherein The first and second opposing sides are formed with grooves for alignment with a first portion of a housing of the tensioner.

13. A tensioning device configured to simultaneously tension multiple locating bolts of a multi-locating bolt tensioner, the tensioning device comprising: a housing adapted to accommodate a drive gear; one or more planetary gears retained within the housing and adapted to mesh with the drive gear; a ring gear surrounding and meshing with the one or more planet gears; a plurality of main shaft gears held in the housing, the main shaft gears including a main shaft adapted to be coupled to the retaining bolt, the main shaft gears being disposed about the ring gear and meshing with an outer side of the ring gear; wherein adjacent main shaft gears are axially offset and partially overlap to reduce the angular spacing between the gears; Thus, in use, the drive gear rotates the one or more planet gears, which in turn rotate the mainshaft gear via the ring gear, to tighten the set bolt.

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