Tightening tool equipped with a visual clamping condition device

Abstract

Tightening tool equipped with a visual clamping condition device, comprising an elongated body (11) having a handle (12) at one end, on this body (11), there is an electronic processing block (14) containing electronic control circuits and an electronic processing unit. At the opposite end of the body having the handle, there is a seat (13) into which a plurality of inserts can be alternatively inserted, each insert is suitable for engaging the tool with a corresponding type and / or size of mechanical organ or element (screw, nut, etc.) on which the tool is intended to act. On this arm, there are sensor means suitable for detecting the tightening conditions exerted on this mechanical organ. Said visual device is controlled by this electronic processing unit and includes at least three light groups (21, 22, 23), which assume a plurality of on and off sequences describing the wrench tightening phases, in which each light group is able to take on at least three distinct colors, so that each color is associated with the information complete tightening, tightening in progress and incorrect tightening or error.

Description

[0001] Tightening tool equipped with a visual clamping condition device

[0002] The present invention relates to an electronic tool for the controlled tightening of mechanical organs; this tool can be, for example, a torque wrench in which the tightening torque exerted on the bolt to be tightened be controlled.

[0003] Tightening tools are known in the art, which comprise a body, containing various control and, possibly, driving organs, to which one of several removable inserts is coupled, each of which is intended to engage a corresponding type of mechanical organ (e.g., the head of a screw, with male or female coupling) on which the tool is intended to act.

[0004] Electronic tools of this type comprise sensors, among which a torque sensor, to detect the torque exerted on the mechanical organ and other relevant parameters, so as to allow a controlled tightening of the mechanical organ through appropriate processing means which show various relevant parameters to the operator and, when necessary, command the tightening operation.

[0005] Patent EP2326464 describes a tool of this type in the form of a torque wrench, which comprises a body, containing the control circuits and processing units of the wrench, a handle on one side (advantageously containing rechargeable batteries to power the wrench), and an arm on the other side. The body advantageously has a display for displaying operational information and data, and a keyboard which allows to insert data and commands. A tool head which must be coupled with the type of mechanical organ (e.g., the head of a screw, with male or female coupling) on which the wrench is intended to act is interchangeably inserted into a dedicated seat at the end of the arm.

[0006] The sensors that measure the torque to be exerted on the organ to be tightened are placed on the arm and comprise at least one strain gauge, which is a sensor whose electrical resistance changes based on the deformation it undergoes; it thus converts force, pressure, tension, weight, etc., into a change in electrical resistance that can be measured.

[0007] The value of the torque exerted is typically available on the wrench display or indicated near it using specific light and / or acoustic signals.

[0008] Patent EP4076846 describes a torque wrench equipped with a visual clamping condition device controlled by a wrench electronic processing unit. This device comprises an annular support linked to the wrench, e.g., the arm, to which a plurality of light groups are associated, being arranged in a circular arc along the ring and are composed each of equidistant light points along the ring. These points are suitable for lighting up progressively when the tightening is completed.

[0009] These types of wrenches, known as electronic wrenches, can adopt tightening control strategies based on parameters different from each other. For example, it is possible to set a tightening strategy by controlling only the tightening torque and optionally monitoring the tightening angle. Or a tightening strategy can be set by controlling both the tightening torque and the tightening angle.

[0010] For all strategies, however, it is important to monitor the progression of the tightening for these parameters.

[0011] Furthermore, for each of these strategies, different information must be effectively communicated to the operator during the different tightening phases for a controlled tightening operation.

[0012] Another type of wrench is the so-called mechatronic wrench, which is a tightening tool which comprises a mechanical part and an electronic part. The mechanical part is represented by the click mechanism, that ensures the desired tightening is reached using the "click signal”.

[0013] Specifically, this mechanical torque detection mechanism provides the operator with the sensation of a force being applied which is suddenly reduced when the tightening torque has reached the set / desired torque value. This sensation is a tactile feedback for the operator, signalling the completion of the tightening.

[0014] The electronic part monitors the tightening torque and / or the tightening angle. An example of this type of wrench is provided in Patent EP3372344.

[0015] In a wrench of this type, but also for an electronic wrench, the object to be achieved or the problems to be solved are to reduce operator errors and potential joint damage, avoiding excessive torque or angle, improving the accuracy of results, especially for tight tolerances, through controlled tightening, and enhancing the operator's experience.

[0016] According to the present invention, for both a mechatronic wrench and an electronic wrench, a visual tightening device has been provided comprising some lighting groups (preferably LEDs) to display the tightening state. Information regarding the tightening and its progression is communicated through these light indicators. One aspect of the present invention relates to a tightening tool having the features of claim 1.

[0017] Further objects and advantages of the present invention will become apparent from the following description and the attached drawings, provided solely by way of illustrative example and not limitation, in which:

[0018] Figure 1 is a perspective view of the tightening tool according to the present invention;

[0019] Figures 2 and 3 illustrate the light signalling device in various on configurations;

[0020] Figures 4 and 5 illustrate two respective on sequences of the lighting groups in the signalling device according to the present invention,

[0021] Figure 6 is a front view of the tightening tool according to another embodiment of the present invention. Referring to the cited figures, the tightening tool according to the present invention comprises an elongated body 11 having a handle 12 at one end (preferably containing rechargeable batteries to power the wrench). On this body 11, in a substantially intermediate position, there is an electronic processing block 14 containing electronic control circuits and an electronic processing unit.

[0022] On this block, command buttons and electrical connection ports (e.g., USB, Ethernet, etc...) can be provided.

[0023] Using these ports or using a wireless connection, the wrench can be connected to external processing units. A wired connection can also be provided to provide an external power.

[0024] At the opposite end of the body having the handle, there is a seat 13 into which a plurality of inserts can be alternatively inserted. For example, each insert will be suitable for engaging the wrench with a corresponding type and / or size of mechanical organ or element (screw, nut, etc.) on which the tool is intended to act.

[0025] Although for simplicity, the inserts shown are all of similar size, elongated inserts or inserts with arms of particular shapes can also be provided, as known in the field.

[0026] The tool comprises sensor means (e.g., made with strain gauges arranged in the arm) for detecting the tightening conditions, such as for example sensors of the torque exerted on the mechanical organ and also a sensor (e.g., gyroscopic) for detecting the tightening angle.

[0027] The mechatronic wrench comprises therein a so-called "click" torque detection mechanism for torque wrenches, for example of the cam type having a cam and a roller brought into elastic contact using a spring.

[0028] According to one aspect of the present invention, the tool comprises a lighting signalling device of the conditions of the tightening operations.

[0029] This device can be applied both to mechatronic wrenches (of the type having a click mechanism) or even just to electronic wrenches alternatively or complementarily to digital or analogical numerical indications in which it provides an indication of the correct tightening in various phases of the same.

[0030] This device comprises at least three light groups 21, 22, and 23 which assume a plurality of on and off sequences describing the wrench tightening phases.

[0031] Each light group is able to take on at least three distinct colors, so that each color is associated with the information complete tightening, tightening in progress or incorrect tightening (error). To this end, each group is, for example, made up of RGB LEDs or other equivalent multicolor light signaller.

[0032] Preferably, each light group can assume the conditions of:

[0033] • Turned off;

[0034] • Turned on in the progress tightening color

[0035] • Flashing in the progress tightening color;

[0036] • Turned on in the complete tightening color;

[0037] • Turned on (flashing) in the incorrect tightening or error color, defining configurations for tightening in progress, with related progress, complete tightening, and incorrect tightening or error state.

[0038] Both the complete tightening configuration and the error configuration can be accompanied by a characteristic sound (auditory feedback)).

[0039] Preferably, the light groups are placed on the block 14 and comprise small rectangles placed side by side along the longitudinal axis of the body, as particularly visible in Figure 1.

[0040] Additionally, in Figures 2 and 3 the three groups are visible in configurations they are, respectively, all turned off, all turned on with the colors for tightening in progress, complete tightening, or error.

[0041] The selection of colors for tightening in progress, complete tightening, and error corresponds to the common meaning of the colors itself.

[0042] Preferred colors for this purpose are green: correct tightening, flashing red: error, solid or flashing white: tightening in progress. Within the scope of this invention, there is nothing to prevent the selection of the colors providing the same meaning. For example, white could be replaced with yellow, and so on. The flashing must be easily visible to the operator's eye, so a flashing frequency of about 1 Hz was selected.

[0043] According to the present invention, the on and off sequence of the light groups provides that they are initially all turned off, during the intermediate tightening phases, the groups, starting from the first, from the right or from the left, and in succession one after the other, flash or light up in the progress tightening color until the programmed tightening is reached, when they light up in the correct tightening color or the error color flashing.

[0044] According to the present invention there are a plurality of sequences for the intermediate tightening phases.

[0045] For example, in Figure 4, each group in succession, starting from the first on the right or the left, first begins to flash and then is solidly lit. In the case where there are three groups, five (or six, if the phase with the three groups turned on in the progress color is also considered) on configurations are then defined, corresponding to the same number of intermediate tightening stages, which can respectively indicate 0, 30, 50, 75, and 90% of the tightening completion.

[0046] For example, in Figure 5, each group in succession starting from the first on the right or the left is solidly lit. In the case where there are three groups, three on configurations are defined which correspond to three intermediate tightening stages, which can respectively indicate 0, 30, and 85% of the tightening completion.

[0047] Thus, by varying the number of groups and the on configurations, more sequences can be created depending on the requirements.

[0048] Programming the tightening strategy (comprising tightening torque and angle control) and the various on sequences of the device groups is performed on the electronic processing unit of the electronic processing block 14.

[0049] The torque and angle sensors detect the tightening parameters and provide them to this processing unit, which turns the light groups on according to the programmed sequence.

[0050] If the wrench hosting the device of the present invention is a mechatronic wrench, thus also provided with a click mechanism, each sequence of turning the light groups on can be programmed so as to position the click event at a specific on configuration.

[0051] Indeed, the click mechanism is manually or electronically adjustable to a prefixed tightening torque. This click tightening torque can correspond to an on configuration expressing a prefixed intermediate percentage of tightening completion (e.g., 90% of the target). In this case, the processing unit is able to adopt the temporary drop in the detected torque after the click, maintaining the last configuration of turning the sequence on until the torque resumes rising beyond this prefixed percentage. Alternatively, the device of the present invention operates independently of the click mechanism. Still according to a further alternative, the preset tightening torque on the click mechanism corresponds to the complete tightening configuration (all groups turned on in the complete tightening color).

[0052] The present invention has the following advantages.

[0053] The operator is well-informed about the tightening state at each phase of the tightening process. Each phase is unique and easily distinguishable. The transition from the initial state to the final state occurs not only based on the color of the group, but also based on the temporal behaviour (e.g., flashing and then solid). No two successive states are identical in color or temporal behaviour. This makes the operator’s guidance much easier to follow. The clear transitions transmit the semantic changes (e.g.: from "torque controlling / monitoring" to "angle controlling / monitoring" and vice versa) in certain tightening strategies.

[0054] Some transitions are marked by multiple feedback modes, such as the click (tactile) and the acoustic signal (auditory), along with the visual signals from the light groups.

[0055] According to the present invention, the verification device comprises a light projection assembly 24 configured to project light in the direction of the tool head and thus the joint to be tightened. This projection group preferably assumes the same colors (thus the progress tightening, complete tightening, or error configurations) as the lighting groups 21, 22, and 23, so that the operator, even not looking at the wrench body direction, but focusing on the joint, is able to know the state of progress or complete tightening. This projection group 24 is preferably placed on the block 14 as the other groups, but placed on the front part of the same, arranged on the part facing the tool head. This placement facilitates the projection of light towards the tool head.

Claims

CLAIMS1. Tightening tool equipped with a visual clamping condition device comprising• an elongated body (11) having a handle (12) at one end,• on said body (11) an electronic processing block (14) containing electronic control circuits and an electronic processing unit is present,• at the opposite end of the body providing the handle, there is a seat (13) into which a plurality of inserts can be alternatively inserted, each insert is suitable for engaging the tool with a corresponding type and / or size of mechanical organ or element (screw, nut, etc.) on which the tool is intended to act,• on said arm there are sensor means suitable for detecting the clamping conditions exerted on this mechanical organ, characterized in that said visual clamping condition device is controlled by said electronic processing unit and includes at least three light groups (21,22,23) which assume a plurality of on and off sequences describing the tool tightening phases, in which each light group is able to take on at least three distinct colors, so that each color is associated with the information complete tightening, tightening in progress and tightening not carried out correctly or error.

2. Tightening tool according to claim 1, in which each light group can assume the condition of off, on of the color of tightening in progress, on of the color of complete tightening, on of the color of tightening not carried out completely or error, so as to define configurations of tightening in progress, of complete tightening and of tightening not carried out correctly or error.

3. Tightening tool of claim 2, wherein the assemblies when turned on in a progressing tightening configuration may flash or be solid.

4. Tightening tool according to claim 2, wherein the assemblies when in a full tightening configuration are all solidly lit, while in a fault configuration they are flashing.

5. Tightening tool according to claim 1, wherein each light group is made up of RGB LEDs.

6. Tightening tool according to claim 1, in which the light units are placed on the block (14) and are small rectangles placed side by side along the longitudinal axis of the body (11).

7. Tightening tool of claim 1, wherein the correct tightening color is green, the error color is red, and the progress tightening color is white.

8. Tightening tool according to claim 1, in which this sequence of turning the lighting groups on and off provides that before tightening the groups are all turned off, during the intermediate tightening phases the groups starting from the first, from the right or from the left and in succession one after the other they flash or light up in the color of tightening in progress, until the programmed tightening is reached, when they light up in the color of correct tightening or the error color.

9. Tightening tool according to claim 1, wherein both the completed tightening pattern and the fault pattern may be accompanied by a characteristic sound.

10. Tightening tool according to claim 1, wherein the display device includes a light projection assembly (24), configured so as to project the light in the direction of the tool head and therefore of the joint to be tightened.

11. Tightening tool according to claim 10, in which this projection group takes on the same colors, therefore the tightening configurations in progress, complete or error, as the lighting groups (21,22,23).

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