US-12618733-B2 - Tension monitoring apparatus including a fixing with a shank under tension and a strain sensor embedded in the shank where the strain sensor is connected to a data processing means

US12618733B2US 12618733 B2US12618733 B2US 12618733B2US-12618733-B2

Abstract

Disclosed herein is a tension monitoring apparatus. The apparatus comprises a fixing with a shank which in use is under tension, a strain sensor embedded in the shank of the fixing and configured to generate a strain sensor signal corresponding to tension in the shank. The apparatus further comprises a data processing means configured to receive the strain sensor signal, process the strain sensor signal in accordance with one or more characterising parameters associated with the strain sensor and thereby generate corresponding strain sensor data indicative of a strain to which the shank is subject. Additionally, the apparatus comprises a wireless transmitter for communicating the strain sensor data to a remote receiver, wherein the data processing means and the wireless transmitter are mounted in a module fixed to an end of the fixing.

Inventors

Steve Lowry
Tomasz Rosinski
Krzysztof Rosinski
Jarek Rosinski

Assignees

Copper State Bolt & Nut Company, Inc.

Dates

Publication Date: 20260505
Application Date: 20220218
Priority Date: 20210223

Claims (20)

1 . Tension monitoring apparatus comprising: a fixing with a shank which in use is under tension; a strain sensor embedded in the shank of the fixing and configured to generate a strain sensor signal corresponding to tension in the shank; data processing means configured to receive the strain sensor signal, process the strain sensor signal in accordance with one or more characterizing parameters associated with the strain sensor and thereby generate corresponding strain sensor data indicative of a strain to which the shank is subject, and a wireless transmitter for communicating the strain sensor data to a remote receiver, wherein: the data processing means and the wireless transmitter are mounted in a module fixed to an end of the fixing; the module further comprises an interconnect for connecting the strain sensor and the data processing means; and the interconnect comprises memory having stored thereon one or more of the characterizing parameters, said characterizing parameters retrievable by the data processing means for use when generating the strain sensor data.
2 . Tension monitoring apparatus according to claim 1 , wherein the shank is a threaded shank.
3 . Tension monitoring apparatus according to claim 2 , wherein the fixing is a bolt said bolt comprising a bolt head located at an end of the threaded shank.
4 . Tension monitoring apparatus according to claim 3 , wherein the module is incorporated in the head of the bolt.
5 . Tension monitoring apparatus according to claim 1 , wherein the module comprises a press fit insert fixed in a corresponding insert receiving aperture at the proximal end of the fixing, said module comprising a cap enclosing the data processing means and wireless transmitter, said cap removably attached to the press fit insert.
6 . Tension monitoring apparatus according to claim 5 , wherein the cap is removably attached to the press fit insert by virtue of an intermediate adaptor secured to the press fit insert, said intermediate adaptor comprising an outer threaded face configured to engage with a corresponding inner threaded face of the cap.
7 . Tension monitoring apparatus according to claim 6 , wherein the interconnect is fixed to the press fit insert.
8 . Tension monitoring apparatus according to claim 7 , comprising a plurality of components that are detachable from the module by removing the cap, said plurality of components comprising the data processing means and the wireless transmitter.
9 . Tension monitoring apparatus according to claim 7 , wherein the plurality of components that are detachable from the module further comprise a battery.
10 . Tension monitoring apparatus according to claim 9 , wherein the interconnect is provided on a first circuit board arrangement and the data processing means is located on a second circuit board arrangement.
11 . Tension monitoring apparatus according to claim 10 , wherein the second circuit board arrangement comprises an upper board and a lower board and the battery is enclosed between the upper board and the lower board.
12 . Tension monitoring apparatus according to claim 1 , wherein the interconnect and the data processing means are connectable via an interface, said interface comprising a first interface part and a second interface part, wherein said first interface part comprises a plurality of pins and said second interface part comprises a plurality of substantially circular conducting tracks, wherein the plurality of pins are positioned on the first interface part such that when the first interface part and second interface part are concentrically aligned, each pin contacts one of the circular conducting tracks irrespective a rotational alignment of the first interface part and second interface part.
13 . Tension monitoring apparatus according to claim 1 , wherein the characterizing parameters comprise calibration data determined during a calibration process performed on the sensor and for mapping strain sensor signal output values with sensor measurement values.
14 . Tension monitoring apparatus according to claim 13 , wherein the calibration data is data indicative of a strain sensor signal value corresponding to a zero-measurement value.
15 . Tension monitoring apparatus according to claim 1 , wherein the characterizing parameters comprise identity data identifying the tension monitoring apparatus and for including in the strain sensor data transmittable to the remote receiver.
16 . Tension monitoring apparatus according to claim 1 , wherein the interconnect comprises a gain amplifier for applying a predetermined gain to the strain sensor signal before it is received by the data processing means.
17 . Tension monitoring apparatus according to claim 1 , wherein the strain sensor is located at a distal end of an axial bore extending part way down a length of the shank of the fixing.
18 . Tension monitoring apparatus according to claim 1 , further comprising temperature sensing means, said temperature sensing means configured to generate a temperature sensor signal indicative of a detected temperature, said data processing means configured to receive the temperature sensor signal, process the temperature sensor signal and generate corresponding temperature sensor data, said wireless transmitter configured to communicate the temperature sensor data to the remote receiver.
19 . Tension monitoring apparatus according to claim 1 , further comprising acceleration detecting means, said acceleration detecting means configured to generate an acceleration sensor signal indicative of a detected acceleration to which the apparatus is subject, said data processing means configured to receive the acceleration sensor signal, process the acceleration sensor signal and generate corresponding acceleration sensor data, said wireless transmitter configured to communicate the acceleration sensor data to the remote receiver.
20 . Tension monitoring apparatus according to claim 1 , further comprising magnetic field detecting means, said magnetic field detecting means configured to generate a magnetic field sensor signal indicative of a detected change in magnetic field, said data processing means configured to receive the magnetic field sensor signal, process the magnetic field sensor signal and if the magnetic field sensor signal is indicative of a tightening tool being applied to the fixing, said data processing means is configured to activate the strain sensor, receive the strain sensor signal and generate strain sensor data for communicating to the remote receiver.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This is a national stage application filed under 37 U.S.C. 371 based on International Patent Application No. PCT/GB2022/050457, filed on Feb. 18, 2022, and entitled “TENSION MONITORING APPARATUS”, which claims priority to United Kingdom Application No. 2102554.9, filed on Feb. 23, 2021, entitled “TENSION MONITORING APPARATUS”, the contents of which are incorporated herein by reference in their entirety for all purposes. TECHNICAL FIELD The present invention relates to tension monitoring apparatus, in particular tension monitoring apparatus comprising a fixing, such as a threaded bolt or stud, and including a strain sensor. BACKGROUND In many industrial applications threaded fixings are used as a means to fix components together. A typical threaded fixing is a bolt. Such a fixing arrangement comprises a head fixed to a threaded shank and a corresponding nut. Other examples include threaded studs comprising a threaded shank and two or more corresponding bolts. Two or more components to be secured together are each provided with a suitable shank receiving aperture through which the shank is inserted. For bolt fixings, the nut is then screwed onto the distal end of the shank and the head of the bolt and the nut are rotated in opposite directions relative to each other to generate a securing force which secures together the components through which the shank of the bolt is inserted. Similarly, for stud fixings, the threaded shank is positioned and then two or more bolts are positioned either side of the element or elements to be fixed and rotated in opposite directions to generate the securing force. In certain settings, for example where large bolts or studs are used to secure together structurally critical components, it is critical that fixings do not become loose. Techniques for monitoring the securing force generated by a bolt arrangement include monitoring the tension applied to the shank of the bolt which is directly related to the securing force provided by the bolt arrangement. In one monitoring arrangement, an ultrasonic transducer is positioned at the head of a bolt and the “time of flight” of acoustic pulses from the ultrasonic transducer is used to monitor a length of the shank of the bolt and thereby infer information about the tension applied to the shank of the bolt. In another monitoring arrangement, a mechanical load monitoring arrangement, comprising a rod, is inserted down the length of the bolt and a gauge provided in the head of the bolt which provides a visual indication of the tension applied to the bolt shank. Such techniques are comparatively complicated to implement and require careful and time-consuming calibration if they are to be implemented accurately. It is an aim of embodiments of the invention to address these drawbacks. SUMMARY OF THE INVENTION In accordance with a first aspect of the invention, there is provided a tension monitoring apparatus. The tension monitoring apparatus comprises a fixing with a shank which in use is under tension; a strain sensor embedded in the shank of the fixing and configured to generate a strain sensor signal corresponding to tension in the shank; data processing means configured to receive the strain sensor signal, process the strain sensor signal in accordance with one or more characterising parameters associated with the strain sensor and thereby generate corresponding strain sensor data indicative of a strain to which the shank is subject, and a wireless transmitter for communicating the strain sensor data to a remote receiver, wherein the data processing means and the wireless transmitter are mounted in a module fixed to an end of the fixing. Optionally, the shank is a threaded shank. Optionally, the fixing is a bolt said bolt comprising a bolt head located at an end of the threaded shank. Optionally, the module is incorporated in the head of the bolt. Optionally, the module further comprises an interconnect for connecting the strain sensor and the data processing means, wherein the interconnect comprises memory having stored thereon one or more of the characterising parameters, said characterising parameters retrievable by the data processing means for use when generating the strain sensor data. Optionally, the module comprises a press fit insert fixed in a corresponding insert receiving aperture at a proximal end of the fixing, said module comprising a cap enclosing the data processing means and wireless transmitter, said cap removably attached to the press fit insert. Optionally, the cap is removably attached to the press fit insert by virtue of an intermediate adaptor secured to the press fit insert, said intermediate adaptor comprising an outer threaded face configured to engage with a corresponding inner threaded face of the cap. Optionally, the interconnect is fixed to the press fit insert. Optionally, the tension monitoring apparatus comprises a plurality of components that are detachable from t