EP3144104B1 - Spanner and method for tightening and marking - Google Patents

Description

GENERAL TECHNICAL FIELD AND PRIOR ART

The present invention relates to the field of bolted mechanical assemblies and, more particularly, the verification and monitoring of the tightening tension of an assembly for a railway application, in particular a bolted assembly. As a reminder, a bolt comprises a screw on which is screwed a clamping nut.

A railroad track comprises in a known manner a plurality of mechanical members which are bolted together, for example rails or splints. To ensure optimal assembly, it is necessary that the tightening tension of the bolt is adapted. For this purpose, an operator uses a torque wrench to tighten the bolt and control its tightening tension.

With reference to the figure 1 in order to monitor the tightening tension, an operator uses a marking pen to make a mark M extending continuously on the screw V and the nut E of the bolt B after tightening. Preferably, the mark M also extends continuously between the nut E and the workpiece to be clamped. The presence of the M mark allows operators to distinguish bolts B which have been tightened (presence of the M mark) from those which have not yet been tightened (absence of the M mark). In addition, the presence of the M mark makes it possible to visually detect any loosening of the bolt B. Indeed, in case of loosening, the nut E moves relative to the screw V, which breaks the continuity of the mark M, a first part M1 being located on the screw V and a second part M2 being located on the nut E at a distance from the first part M1 as shown in FIG. figure 2 . Any loosening can thus be visually identified by an operator.

In practice, the alternating use of a torque wrench and a marking pen is a waste of time. An immediate solution would be to attach a marking pen directly to the torque wrench to directly mark the bolt at the end of the tightening, that is, when the wrench head is still in contact with the bolt. Nevertheless, such a torque wrench would have significant dimensions, which would penalize its handling, in particular, in confined spaces.

WO 02/14023 A1 discloses a wrench for marking an automatic nut when it is tightened.

An object of the present invention is to obtain a torque wrench capable of marking a bolt after tightening whose dimensions are reduced and which is easy to use for an operator.

GENERAL PRESENTATION OF THE INVENTION

To this end, the invention relates to a tightening wrench comprising a longitudinal body, extending along a key axis, comprising a handle adapted to be gripped by hand by an operator and a clamping head extending along an axis. clamping device adapted to cooperate with an axial bolt according to a first angular orientation of the key around its key axis.

The key is remarkable in that it comprises at least one marking member capable of marking an axial bolt according to a second angular orientation of the key around its key axis. Thus, advantageously, the marking member does not present an inconvenience during clamping operations (first angular orientation) while being easily accessible by simple rotation of the tightening key. Thus, the key has several functions that can be used according to its angular orientation. The key according to the invention advantageously allows to perform a dual function without affecting the clamping operations. This is particularly advantageous when clamping operations must be performed in confined spaces.

Subsequently, the "axis of tightening Xs" is the axis around which the wrench 1 must be rotated to allow the tightening of a bolt. The invention is presented for the marking of a bolt but it also applies to a screw implanted in a threaded part without nut or to a threaded member screwed into a thread.

Preferably, the first angular orientation and the second angular orientation are spaced apart by a separation angle of between 70 ° and 110 °, preferably 90 °. As the marking member extends in a plane transverse to the clamping axis, the marking member can have significant dimensions without disturbing the operator during a clamping step.

Preferably, the key axis and the clamping axis are intersecting and orthogonal.

Preferably, the marking member is configured to mark a bolt in a plane orthogonal to the clamping axis, i.e., containing the bolt axis. Preferably, the marking member is configured to mark a bolt in a plane containing the key axis. Thus, it takes advantage of the longitudinal body of the wrench to align the marking member with a bolt. The marking is thus carried out accurately and repeatably. Preferably, the marking member is configured to spray a marking product along an axis parallel to the key axis.

Preferably, the tightening key comprises a wedging member adapted to cooperate with an axial bolt according to the second angular orientation of the key around its key axis. The wedging member further improves the accuracy of the marking by being positioned against the nut of the bolt to be marked so as to form a mark extending continuously between the screw and the nut. Preferably, said wedging member is made of material of the longitudinal body of the wrench, which reduces the cost.

Preferably, said wedging member comprises at least one abutment notch, preferably at least two abutment notches. Thus, the abutment notch has a flat wall for stably resting on the nut of the bolt to perform the marking. The use of several stop surfaces makes it possible to adapt to several types of bolts so that the mark is continuous between the screw and the nut and this, for all types of screws and nuts. Preferably, the abutment notches are offset relative to each other to accommodate nuts of different thicknesses.

Preferably, the marking member comprises an actuator, preferably a joystick. It is thus sufficient for the operator to act on the joystick to perform a marking. Preferably, in order to limit the bulk, the actuator is mounted on the longitudinal body of the wrench, in particular between the handle and the clamping head.

More preferably, the marking member comprises a paint cartridge. Such a cartridge has a significant autonomy and is simple to replace.

Preferably, the mark is in the form of a line.

In a preferred manner, the tightening key comprises a communication functional module able to communicate with at least one data network. The key advantageously forms a "connected object" and makes it possible to receive data (clamping instructions, etc.) and to transmit them (clamping voltage, marking confirmation, etc.). Such a functional module makes it possible to improve the monitoring of the clamping.

Preferably, the wrench is a torque wrench and can measure a tightening tension.

• une étape de serrage d'un boulon axial par la tête de serrage, la clé de serrage étant positionnée selon une première orientation angulaire autour de son axe de clé ;
• une étape de modification de l'orientation de la clé de serrage de manière à ce que la clé de serrage soit positionnée selon une deuxième orientation angulaire autour de son axe de clé ; et
• une étape de marquage dudit boulon axial, de préférence, de manière continue entre l'écrou et la vis dudit boulon par la clé de serrage dans ladite deuxième orientation angulaire.

The invention also relates to a method of clamping and marking a bolt by means of a wrench as previously presented, the method comprising:

• a step of clamping an axial bolt by the clamping head, the clamping key being positioned at a first angular orientation about its key axis;
• a step of changing the orientation of the wrench so that the wrench is positioned at a second angular orientation about its key axis; and
• a step of marking said axial bolt, preferably continuously between the nut and the screw of said bolt by the wrench in said second angular orientation.

Preferably, the method comprises a step of measuring the clamping tension of the bolt and a step of marking said tightening tension on said bolt.

Thus, the marking makes it possible, on the one hand, to visually identify whether a loosening has occurred and, on the other hand, to know the initial tightening tension. With this information, an operator can advantageously detect a loosened bolt and restore the clamping tension conveniently and quickly. It is not necessary to consult a database grouping each bolt and its associated clamping tension.

PRESENTATION OF FIGURES

• la figure 1 est une représentation schématique d'un boulon serré et marqué ;
• la figure 2 est une représentation schématique d'un boulon desserré ;
• les figures 3 et 4 sont des représentations schématiques d'une clé dynamométrique selon l'invention ;
• les figures 5 à 6 sont des représentations schématiques d'étapes de serrage d'un boulon au moyen de la clé dynamométrique ;
• la figure 7 est une représentation de la clé dynamométrique au cours d'une étape de marquage ; et
• la figure 8 est une représentation rapprochée du boulon suite à l'étape de marquage.

The invention will be better understood on reading the description which will follow, given solely by way of example, and referring to the appended drawings in which:

• the figure 1 is a schematic representation of a tight and marked bolt;
• the figure 2 is a schematic representation of a loose bolt;
• the Figures 3 and 4 are schematic representations of a torque wrench according to the invention;
• the Figures 5 to 6 are schematic representations of steps of tightening a bolt by means of the torque wrench;
• the figure 7 is a representation of the torque wrench during a marking step; and
• the figure 8 is a close representation of the bolt following the marking step.

It should be noted that the figures disclose the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate.

DESCRIPTION OF ONE OR MORE MODES OF REALIZATION AND IMPLEMENTATION

As illustrated in Figures 3 and 4 , there is shown a torque wrench 1 according to a first embodiment of the invention. The torque wrench 1 comprises a longitudinal body 10, extending along a key axis Xc, which comprises, at a first end, a handle 11 adapted to be grasped manually by an operator and, at a second end, a head 12 extending along a clamping axis Xs adapted to cooperate with an axial bolt according to a first angular orientation P1 ( Figures 5-6 ) of the key around its key axis Xc. Subsequently, the "axis of tightening Xs" is the axis around which the tightening key 1 must be turned to allow clamping. With reference to the figure 3 the key axis Xc and the clamping axis Xs are intersecting and orthogonal.

In this example, the longitudinal body 10 is flattened and the clamping axis Xs extends along the thickness of the longitudinal body 10. With reference to the figure 5 , the clamping head 12 comprises a connecting piece 2 adapted to receive a removable tip 7 to cooperate with a nut of a bolt. Advantageously, a plurality The end piece 7 can be adapted to the torque wrench 1 in order to cooperate with a plurality of bolt types of different sizes and shapes. In this example, the clamping head 12 has a ratchet mechanism to limit operator fatigue. It goes without saying that such a mechanism is optional.

The tightening key 1 further comprises means for measuring the tightening tension. As will be presented hereinafter, the wrench 1 comprises means for displaying the tightening tension, for example, a liquid crystal screen.

According to the invention, again with reference to Figures 3 and 4 the tightening wrench 1 also comprises a marking member 4 capable of marking an axial bolt according to a second angular orientation P2 ( Figure 7 ) of the tightening wrench 1 around its key axis Xc. In other words, the marking member 4 can not be activated when the tightening key 1 is in the clamping position, that is to say, according to the first angular orientation P1. As will be presented later, this allows to offer optimal conditions of clamping and marking.

In this example, the first angular orientation P1 and the second angular orientation P2 are spaced apart by an angle of 90 °. Thus, during a tightening, the marking member 4 has a bulk only in the plane transverse to the clamping axis Xs of the clamping head 12. The size is limited and the clamping facilitated.

With reference to Figures 3 and 4 , the marking member 4 comprises a marking product tank, in particular a paint cartridge 41. It goes without saying that other marking products could be suitable, in particular, ink or gel. The paint cartridge 41 extends axially and is removably mounted to allow its replacement. Advantageously, in the mounted position, the paint cartridge 41 extends parallel to the key axis Xc, which reduces the size of the tightening key Xs.

The paint cartridge 41 is under pressure and has a dispensing valve which is adapted to dispense paint when the valve is constrained along the axis of the paint cartridge 41. It goes without saying that the marking member 4 could understand a different energy source, for example, an electric battery, a pneumatic cartridge or other.

The marking member 4 further comprises a spray nozzle 42 in which is removably mounted the paint cartridge 41, in particular, its dispensing valve. The spray nozzle 42 is hingedly mounted to the longitudinal body 10 of the wrench 1 to facilitate mounting of the paint cartridge 41. Still with reference to the Figures 3 and 4 , the marking member 4 also comprises an actuator which is adapted to constrain the paint cartridge 41 along its axis and thus allow a distribution of paint by the spray nozzle 42. In this example, the actuator is in the form of of a joystick 43 but it goes without saying that a handle or a button could also be suitable.

According to a preferred aspect, the marking member 4 is adapted to print data, in particular, the tightening tension measured by the tightening key 1 during tightening. For example, the marking member 4 comprises a programmable spray nozzle 42 in order to be able to form a mark comprising numbers and / or letters. Alternatively, the marking member 4 may form a symbol which corresponds to a predetermined clamping tension. Thus, a single symbol makes it possible to conveniently represent a clamping tension.

With reference to the figure 3 , the handle 43 has a connecting portion 43a adapted to cooperate with the paint cartridge 41 and an actuating portion 43b which is located on the opposite side to the paint cartridge 41 relative to the longitudinal body 10 of the wrench 1 Thus, advantageously, the weight and bulk of the tightening key 1 is balanced. In this example, the handle 43 is hinged to the longitudinal body 10 of the wrench 1, preferably around an axis parallel to the clamping axis Xs. The connecting portion 43a includes a housing adapted to receive the paint cartridge 41. Preferably, as illustrated in FIGS. Figures 3 and 4 , the marking member 4 comprises resilient return means, in particular, leaf springs 44 mounted between the actuating portion 43b and the longitudinal body 10 of the wrench 1. The leaf spring 44 advantageously allow to return the handle 43 to its initial position after actuation to stop any spraying.

With reference to the figure 4 , the tightening key 1 comprises a wedging member 5 adapted to cooperate with an axial bolt B according to the second angular orientation P2 of the key 1 around its key axis Xc. The wedging member 5 is made of material of the longitudinal body 10 of the tightening wrench 1 and comprises two abutment notches 51, 52 each having two orthogonal flat surfaces so as to form a wedge wedge adapted to come into position. Stable on the nut of the bolt B. Through the stop notches 51, 53, an operator can form a mark extending continuously between the screw V and the nut E. Preferably, each notch 51, 52 includes a first flat surface orthogonal to the key axis Xc and a second flat surface parallel to the key axis Xc.

The use of several stop notches 51, 52 makes it possible to adapt to several types of bolts B so that the mark M is continuous between the screw V and the nut E and this, for all types of screws V and Preferably, the abutment notches 51, 52 are offset relative to each other to accommodate different thickness nuts. In this example, the stop notches 51, 52 are offset along the key axis Xc and are at different radial distances from said key axis Xc.

With reference to Figures 3 and 4 , the clamping key 1 comprises a housing 3 in which is mounted a communication functional module able to communicate wirelessly with at least one data network, in particular, the Internet network. Thus, the tightening key 1 forms a so-called "connected" object. The functional module has for example a communication card (3G network, etc.) and a battery pack. The housing 3 is fixed to the longitudinal body 10 of the tightening key 1 between its handle 11 and its clamping head 12. The housing 3 further comprises a screen 30 on which are displayed various information, for example, a clamping tension or an instruction to execute.

In this embodiment, the housing 3 comprises motion detection means adapted to determine the orientation of the tightening key 1 and to deduce if the tightening key 1 is used to tighten or to mark a bolt B. The case 3 further comprises actuating detection means, for example an inductive or capacitive sensor, to determine whether the lever 43 is actuated.

Preferably, the housing 3 comprises alarm means (not shown), in particular visual or sound, adapted to attract the attention of the operator in particular during the implementation of clamping and marking procedures. Preferably, the housing 3 comprises light diodes and a loudspeaker.

According to one aspect of the invention, the housing 3 comprises means for identifying a bolt B, for example an RFID reader, so as to associate a predetermined bolt with a predetermined action. For this purpose, each bolt B has an RFID target. Advantageously, the wrench 1 can automatically consult a remote database of bolts to determine what actions should be performed for a predetermined bolt. This is particularly advantageous for allowing operators to follow a predetermined tightening procedure.

Clamping and marking process

An example of implementation of a method of clamping and marking an axial bolt B by means of a wrench 1 according to the invention will now be presented.

With reference to the figure 5 , the tightening wrench 1 is oriented at a first angular position about its key axis Xc so that the clamping axis Xs of the clamping head 12 can cooperate with the bolt B. The clamping head 12 is equipped with a clamping piece 7 which extends axially along the clamping axis Xs and which is aligned with the axis of the bolt B. The clamping piece 7 is chosen so as to cooperate with the nut E of said bolt B.

To allow tightening the nut E on the screw V of the bolt B, the nut E is first screwed by hand by the operator and then using the wrench 1 as shown in the illustration. figure 6 . In this example, the clamping key 1 is ratchet and allows to tighten the nut E in a practical way. It suffices for the operator to grasp the handle 11 and to turn it repeatedly over an angular range around the clamping axis Xs to tighten the nut E. Advantageously, the marking member 4 extends in a plane orthogonal to the clamping axis Xs and encumbered by the operator.

As and when tightening, the clamping tension is displayed on the screen 30 of the housing 3. When the desired clamping tension is reached, the operator stops the Tightening. Preferably, an audible or visual alarm is emitted by the box 3 to warn the operator.

In this example, the box 3 informs the operator that it is necessary to mark the bolt B. For this purpose, the operator moves the tightening wrench 1 to release the nut E and then turns the wrench 1 of 90 ° around its key axis Xc so that the tightening key 1 is oriented in a second angular position. As illustrated in figure 7 , the clamping axis Xs then extends orthogonally to the axis of the bolt B. The clamping key 1 is positioned so that one of the notches 52, 52 of the wedging member 5 cooperates with the nut E which is tight. Thus, the tightening key 1 is precisely positioned relative to the bolt B, the spray nozzle 42 is then facing the nut E and the screw V.

To carry out the marking, the operator acts on the handle 43, which displaces the paint cartridge 41 and causes a spray of paint via the spray nozzle 42 in the direction of the bolt B. As illustrated in FIG. figure 8 the bolt B then has a continuous paint mark M between the nut E and the screw V. Preferably, the paint mark M also extends continuously over the tight piece. Preferably, the mark M is representative of the tightening tension of the bolt. The M mark is convenient and quick to use by simply using the wrench 1, which saves a lot of time.

When the operator releases the constraint on the handle 43, the spring blades 44 act on the handle 43 to move it to the initial position and thus stop any spraying.

The invention has been presented for a torque wrench but it goes without saying that it applies to any type of wrench.

Claims (10)

1. Spanner (1) comprising a longitudinal body (10), extending along a spanner axis (Xc), comprising a handle (11) able to be gripped by hand by an operator and a tightening head (12) extending along a tightening axis (Xs) able to cooperate with an axial bolt (B) according to a first angular orientation (P1) of the spanner (1) about its spanner axis (Xc), spanner characterised in that it comprises at least one marking member (4) able to mark an axial bolt (B) according to a second angular orientation (P2) of the spanner (1) about its spanner axis (Xc).
2. Spanner (1) according to claim 1, wherein the first angular orientation (P1) and the second angular orientation (P2) are spaced by a spacing angle between 70° and 110°, preferably, 90°.
3. Spanner (1) according to one of claims 1 to 2, wherein the marking member (4) is configured to mark a bolt (B) in a plane orthogonal to the tightening axis (Xs).
4. Spanner (1) according to one of claims 1 to 3, wherein the spanner (1) comprises a shimming member (5) able to cooperate with an axial bolt (B) according to the second angular orientation (P2) of the spanner (1) about its spanner axis (Xc).
5. Spanner (1) according to claim 4, wherein said shimming member (5) is from the same material of the longitudinal body (10) of the spanner (1).
6. Spanner (1) according to one of claims 4 and 5, wherein said shimming member (5) comprises at least one abutment notch (51, 52), preferably, at least two abutment notches (51, 52).
7. Spanner (1) according to one of claims 1 to 6, wherein the marking member (4) comprises an actuator, preferably, a control lever (43).
8. Spanner (1) according to one of claims 1 to 7, comprising a functional communication module able to communicate with at least one data network.
9. Method for tightening and marking a bolt by means of a spanner (1) according to one of claims 1 to 8, the method comprising:

   - a step of tightening an axial bolt (B) by the tightening head (12), the spanner (1) being positioned according to a first angular orientation (P1) about its spanner axis (Xc);

   - a step of modifying the orientation of the spanner (1) in such a way that the spanner (1) is positioned according to a second angular orientation (P2) about its spanner axis (Xc); and

   - a step of marking said axial bolt (B) by the spanner (1) in said second angular orientation (P2).
10. Method for tightening and marking as claimed in the preceding claim, comprising:

    - a step of measuring the tightening tension of the bolt (B) and

    - a step of marking said tightening tension on said bolt (B).

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