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Patent Searching and Data


Title:
LOCKNUT
Document Type and Number:
WIPO Patent Application WO/2019/194876
Kind Code:
A1
Abstract:
A locknut for a bolt which can be used in high temperature environments. The locknut includes a frictional force which prevents unauthorized removal of the locknut from the bolt. This frictional force can be set at a desired level and multiple locknuts can be manufactured at this preset level. The locknut can also be manufactured to have an adjustment screw pin which can be used to vary the amount of frictional force therefore permitting the user to individually select the desired force level.

Inventors:
SPRIGGEL, Daniel John (42102 Washington Street, Bermuda Dunes, CA, 92203, US)
Application Number:
US2019/000012
Publication Date:
October 10, 2019
Filing Date:
March 18, 2019
Export Citation:
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Assignee:
SPRIGGEL, Daniel John (42102 Washington Street, Bermuda Dunes, CA, 92203, US)
International Classes:
F16B39/34; F16B37/00; F16B39/00; F16B39/02; F16B39/06; F16B43/00
Domestic Patent References:
WO1998030806A11998-07-16
Foreign References:
GB2233058A1991-01-02
EP2463530A22012-06-13
US0738008A1903-09-01
US2233889A1941-03-04
US1355342A1920-10-12
US3179141A1965-04-20
US3254691A1966-06-07
US1218168A1917-03-06
US0982502A1911-01-24
Attorney, Agent or Firm:
MUNRO, Jack C. (32228 Paauwe Drive, Pauma Valley, CA, 92061, US)
Download PDF:
Claims:
CLAIMS

1. A locknut adapted to be installed on a cylindrical bolt having an exterior threaded surface, said locknut comprising:

a rigid body having an internally threaded through opening which has a longitudinal center axis, said rigid body having a pocket connecting with said through opening;

a slot formed laterally in said rigid body and connecting with said pocket; and a shim to be mounted in said slot and connecting with said pocket, said shim being longitudinally fixed in position by said pocket, a portion of said shim being deflectable, deflecting of said shim causes a frictional force to be applied to said exterior surface of said bolt.

2. The locknut as defined in Claim 1 wherein:

deflection of said shim is accomplished by a protrusion mounted on said shim which is pressed against said rigid body.

3. The locknut as defined in Claim 1 wherein:

deflection of said shim is accomplished by using an adjustable pin threadably mounted in said rigid body.

4. A locknut adapted to be installed on a cylindrical bolt having an exterior threaded surface, said locknut comprising:

a rigid body having an internally threaded through opening which has a longitudinal center axis, said rigid body having a pocket connecting with said through opening;

a slot formed laterally in said rigid body and connecting with said pocket;

a shim to be mounted in said slot and connecting with said pocket, said shim having a centrally located through hole which is in alignment with said through opening when said shim is installed within said pocket, said shim having a rigid peripheral edge which encloses said through hole and a cavity, a ring mounted on said rigid body and is connected to said peripheral edge, said through hole is formed within said ring, a block is attached to a ring segment which is part of said ring and located within said cavity, said ring segment being spaced from said pocket and capable of axial deflection relative to said rigid body, said ring segment to be threadably engaged with said bolt, upon a force being applied to said block a portion of said ring segment will axially deflect applying pressure onto the exterior threaded surface of the cylindrical bolt thereby creating a frictional force between said rigid body and said bolt preventing unauthorized

disengagement of said rigid body from the body from the bolt.

5. The locknut as defined in Claim 4 wherein:

said rigid body having a notch, said notch connecting with said slot, a

protrusion mounted on said block, said protrusion to lockingiy engage with said notch when said shim is installed within said pocket thereby preventing any disengaging movement of said shim from said rigid body.

6. The locknut as defined in Claim 4 wherein:

a first hole formed in said rigid body, said first hole connecting with said cavity; and

a pin mounted within said first hole, said pin having an inner end and an outer end, said inner end to contact said block by moving said pin by using a tool connecting with said outer end said pin can be moved to vary the force applied against said block which will vary said frictional force.

7. The locknut as defined in Claim 6 wherein:

said first hole being internally threaded, said pin being externally threaded, movement of said pin is accomplished by turning of said pin.

8. The locknut as defined in Claim 6 wherein:

said block having a recess, a protuberance mounted on said pin at said inner end, said protuberance to be located within said recess thereby preventing lateral movement of said shim relative to said bolt.

9. The locknut as defined in Claim 4 wherein:

said pocket providing longitudinal restraint for said shim not permitting any longitudinal movement of said shim relative to said body.

Description:
LOCKNUT

Reference To Prior Application

The subject matter of this invention is deemed to be a continuation-in-part of the subject matter disclosed in utility patent application Serial Number 15/330,998, filed November 17, 2016, entitled Locknut.

Background of the Invention

Bolts that connect with a nut have been in common use for many years.

Frequently the bolt installation is in a machinery environment where the machine is operated by an energy source such as gas or electricity. The machine inherently produces vibration and/or thermal expansion/contraction. This vibration and/or thermal expansion causes the nut to loosen on the bolt even though it has been tightly installed. This loosening can cause the nut to separate from the bolt which could result in the member that was being held onto the machine to disengage. This disengagement can be dangerous and could cause the machinery to fail which could result in injury or death to the human operator.

Another environment where loose nuts can be dangerous is wheel nuts that are used to attach wheels on vehicles. It is said that in the United States that forty to sixty accidents or incidents occur each month due to loose wheel nuts. Obviously in the world that number will be much greater.

To overcome nuts loosening on their bolts, it has been common to use a locknut. There are literally hundreds of different types of locknuts all of which require the tight installation by a separate tool such as a wrench and also use of the same tool to disengage the locknut if disengagement is desired. Some locknuts are destroyed when removed thereby requiring a new locknut to be installed. It would be desirable to permit the locknut to be removable and reinstalled. The locking force of the locknut may be adjustable so the locking force can be increased in high vibrational installations to insure that the locknut will never disengage from the bolt even after an extended period of usage. In low vibrational environments it may be desired to have a low locking force that could be achieved by the user installing the locknut by hand not using a wrench.

Summary of the Invention

The first embodiment of this invention has a fixed value of frictional force (locking force) which is constant and must be overcome to install or remove the locknut from the bolt. The customer when purchasing the locknut can select the desired amount of frictional force and then the desired number of locknuts are

manufactured at this force level. The second embodiment of this invention includes an adjustable pin where by turning of this pin the amount of frictional force on the bolt can be varied. This second embodiment can be manufactured with zero amount of frictional force and the customer can then select the desired amount of force.

In both embodiments there is mounted a shim within the rigid body of the nut. The shim is internally threaded which aligns with the internal threads of the nut. The shim has a ring which is to be tightly mounted within a pocket formed in the nut. A shim segment is mounted within the ring which has internal threads that align with the threads of the shim. The shim segment is connected to a block. When pressure is applied to the block, a portion of the shim segment will slightly deflect and apply pressure onto a bolt thread and the greater this deflection the greater the frictional force produced by the locknut.The amount of this deflection is in the thousandths of an inch. The difference between the minimal force level and the maximum force level is just a few thousandths of an inch. In the first embodiment there is a protrusion mounted on the block. When the shim is installed, pressure is applied by the nut against this protrusion which then produces the frictional force. The smaller the protrusion , the less the force. The greater the protrusion, the greater the force. Some installations may only need a small force while other high vibrational installations may require a greater force.

In the second embodiment there is used a threaded pin in contact with the block. Turning of this pin will result in varying the frictional force permitting the user to individually select the desired force level.

One of the objectives of this invention is that the locknut is constructed pf the same material as the bolt. For example, if the bolt is metal then also is the locknut. If the bolt is plastic then also is the locknut. If nylon then so is the locknut. However, most often the bolt and locknut will be constructed of metal which will permit the locknut to be used in high temperature environments.

Another objective of this invention is to construct a locknut which can be manufactured at various locking forces so a specific force level can be selected that will be adequate for the particular installation of the bolt therefore not using a too high force level or a too low force level.

An advantage of this invention is that the locknut can be removed from the bolt and reused. The lock nut is not destroyed which frequently occurs ih prior art locknuts.

Brief Description of the Drawings

Figure 1 is a side elevational view of the locknut of this invention installed on a bolt;

Figure 2 is a longitudinal cut-away view of the first embodiment of locknut of this invention showing the internal construction of the locknut;

Figure 3 is a top isometric view of the first embodiment of locknut showing it in a disassembled state;

Figure 4 is a bottom isometric view of the first embodiment of locknut shown in Figure 3;

Figure 5 is a top isometric view of just the shim used in the first embodiment;

Figure 6 is a side elevational view of the shim shown in Figure 5;

Figure 7 is a view similar to Figure 2 but of the second embodiment of locknut of this invention;

Figure 8 is a bottom isometric view of the second embodiment of locknut with the shim removed;

Figure 9 is a top isometric view of the shim used in the second embodiment of this invention; and

Figure 10 is an isometric view of the adjustment pin used in the second

embodiment. Detailed Description of the Invention

Referring specifically to Figures 1-6 there is shown the first embodiment 20 of this invention installed on a conventional bolt 22. The conventional bolt 22 has a longitudinal series of helical screw threads 24 and a bolt head 26 which is designed to be hexagonal to engage with a tightening tool such as a wrench (not shown). The rigid body of the first embodiment 20 is shown in Figure 2. The first embodiment 20 has a slot 28 formed in its sidewall. The rigid body of the locknut 20 has a notch 30 which connects to slot 28. The screw threads 24 are helical and interconnect forming a continuous series. The threads 24 have a major diameter 23 terminating at a ridge called a crest and a minor diameter 25 called a root. Connecting between each directly adjacent major diameter 22 and minor diameter 25 is an inclined flat surface called a flank 27. There are two flanks 27 per thread 24. All of the threads 24 have the identical crest and root.

The rigid body of locknut 20 will normally be constructed of metal and usually the same material of construction of bolt 22. However, it is possible that the bolt 22 and locknut 20 could be constructed of other rigid material such as plastic or nylon. The bolt 22 has a longitudinal center axis 32. The rigid body of locknut 20 has a longitudinal internally threaded through opening 36 which has screw threads 34. The slot 28 divides the threads 34 into an upper section and a lower section which are separated by a pocket 38. A shim 40 is to be inserted into the slot 28 and will assume a close fitting relationship with slot 28 and pocket 38.

The shim 40 has a ring 42 which is located within pocket 38. Ring 42 has a rigid peripheral edge 44 with there being a threaded through hole 46 enclosed by edge 44. The hole 46 includes screw threads 48 which are in axial alignment and of the same helix with screw threads 24 when shim 40 is installed in pocket 38. When shim 40 in installed in pocket 38 the longitudinal center axis 50 coincides with longitudinal center axis 32.

Ring 42 has a ring segment 52 attached thereto which forms a circular enclosing ring. The rigid peripheral edge 44 has an extension 54 which encloses a cavity 56. The exterior surface of the extension 54 has flat surfaces 58 and 60. When shim 40 is installed in pocket 38 flat surface 58 is flush with flat surface 62 of the rigid body of locknut 20 and flat surface 60 is flush with flat surface 64 of rigid body of locknut 20. The result is in appearance the locknut 20 looks just like a conventional prior art nut (not shown). Ring segment 52 is spaced from the pocket 38 with the remaining portion of the ring 42 being axially fixed relative to shim 40.

Mounted on ring segment 52 is a block 66. The upper surface of block 66 includes an inclined ramp 68. Ramp 68 terminates at flat 70. By observing Figure 6 it can be seen that ramp 68 and flat70 protrude above the upper surface plane of ring 42. The amount of protrusion is defined as distance X in Figure 6. This distance X can vary. Some locknuts 20 can be manufactured with a short distance X while others could be manufactured with a greater distance X. When shim 40 is inserted into slot 28 the inclined ramp 68 will slide against the wall surface of slot 28 causing the ring segment 52 to slightly deflect with a certain deflection being obtained when flat 70 engages with notch 30. The notch 30 prevents lateral movement of shim 40. This deflection produces a frictional force (pressure) against a flank 27 of one of the threads 24 which produces the locking force of the locknut 20. It is possible that the shim 40 could have multiple contact points with two or three flanks 27 not just one contact point. The greater the distance X the greater the greater the frictional force. This force can be varied from a few inch pounds to foot pounds. This is the force that locks the locknut 20 onto the bolt 22. This is the force that must be overcome if the user desires to remove the locknut 20 from the bolt 22 which will normally occur by using a wrench tool (not shown). However if the force is only a few inch pounds, the locknut 20 could be removed by using only the hand of the user.

Referring specifically to Figures 7 -10 there is shown the second embodiment 72 of this invention. The second embodiment 72 is different from the first

embodiment 20 by the frictional force applied to the bolt 22 to be adjustable.

The second embodiment 72 has a similar rigid body 74 which has flats 76 and 78 which are essentially identical to flats 62 and 64. The shim 80 has a flat 82 which is to be flush with flat 76 and also a flat 84 which is to be flush with flat 78. The rigid body 74 has a threaded through opening 86. There is a slot 88 which is essentially identical to slot 28. There is a pocket 90 in the rigid body 74 which is essentially identical to pocket 38. Ring 92 of shim 80 closely fits within pocket 90. Peripheral edge 94 is integral with ring 92. Ring segment 96 is also integral with ring 92 and is essentially identical to ring segment 52. When ring 92 is located in pocket 90, the ring segment 96 is spaced from the pocket 90. Ring segment 96 has a block 98. Block 98 has a smooth bored hole 100. Rigid body 74 has a threaded first hole 102. A pin 104 is threadably engaged with said first hole 102. Pin 104 has an inner end which is formed into a smooth walled protrusion 106. Protrusion 106 is to be located within smooth bored hole 100. When the rigid body 74 is placed at the desired longitudinal position on the bolt 22, the user is to then turn pin 104 to produce the desired frictional force on the threads 24 of the bolt 22. Turning of the pin 104 clockwise will increase this frictional force. Turning of the pin 104 counter clockwise will decrease this frictional force. Pin 104 causes the ring segment 96 to deflect. Ring segment 96 is located within cavity 108 which is enclosed by peripheral edge 94.