Patent Description:
Welding workstations for manually carrying out precision welding or microwelding operations are known, for example, in the orthodontic and in the jewelery fields.

Such welding workstations (see for example <CIT>) comprise, in general:.

In particular, the welding operation is carried out by an operator, who inserts his/her hands inside the process chamber and handles the objects to be welded and/or the welding device, observing the inside of the process chamber by means of the vision system.

The vision system can be, for example, a microscope comprising an objective arranged inside the process chamber and one or more eyepieces, which enable the operator to observe the objects arranged inside the process chamber on an enlarged scale. However, the use of the microscope obliges the operator to remain in a fixed position, with his/her eyes in contact with the eyepieces, for the whole duration of the welding operations. Such posture can be not very ergonomic, especially if kept for prolonged intervals of time, causing discomfort for the operator.

In fact, recent studies within the scope of the ergonomic risk assessment have highlighted the manifestation of muscle-skeletal disorders, eyestrain and mental fatigue due to postures similar to those assumed by the operators of the welding workstations.

Moreover, the use of the microscope as vision system can be even less ergonomic for the operators who wear reading glasses. In fact, such operators use the microscope after taking off their reading glasses, making use of the focusing settings of the instrument for adapting it to sight. However, the repeated taking off of the reading glasses from the face of the operator entails a further eyestrain due to the focusing at different distances.

The vision system can comprise, alternatively, a video camera with an objective arranged inside the process chamber and a screen, which is fixed outside the process chamber and projects the images filmed by the video camera. During the process, the operator carries out the welding operations keeping the visual contact with the screen. Therefore, also in this case, the operator is in a position which is not always ergonomic, since it is not possible for him/her to freely rotate his/her head without losing the visual contact with the screen.

It is further proper to note that the artificial or natural light present in the workplace can easily cause reflections on the screen, causing the risk of glaring the operator. Additionally, the quality of the images reproduced on the screen is not always optimal.

<CIT> discloses welding equipment based on a virtual reality technology and comprising a 3D scanner, a welding wire, a welding gun, a controllable mechanical arm, a universal ball, a control rod and a head-mounted stereoscopic display. <CIT> discloses an integrated jewelry laser spot welder. A space is formed below a mainframe, a cooling-water machine is located in the space, a gap is reserved between the cooling-water machine and the mainframe, and the cooling-water machine is in contact with the ground. <CIT> discloses a welding apparatus including a multi-axis robotic arm having a first end; a welding tool attached to the first end; an image acquisition device attached to the first end and having a light filtering system; the image acquisition device is configured to monitor a welding target and to provide an image of the welding target to an operator; a control unit is configured to control the robotic arm and the welding tool; an input interface for a human operator is associated to the control unit and is configured to provide an input signal to the control unit and to control the robotic arm and welding tool substantially in real time.

Therefore, the need is felt to have a welding workstation where the manual welding operations can be carried out in an ergonomic manner even for prolonged periods of time.

The object of the present invention is to meet the above-described needs.

The abovementioned object is achieved by a welding workstation, by a method of vision of manual welding operations on a welding workstation, and by a method of updating a welding workstation for carrying out manual welding operations as defined in claims <NUM>, <NUM> and <NUM> respectively.

Further preferred embodiments of the present invention are defined in the appended claims.

To better understand the present invention, a preferred embodiment is described in the following, by way of non-limiting example and with reference to the accompanying drawings wherein:.

<FIG> illustrates a welding workstation <NUM> for manually carrying out welding operations of objects <NUM> of various types.

In the following, welding process means any technology that allows jointing, under the action of heat and/or of pressure, two or more pieces made of the same material or of different materials. Specifically, the welding process can be carried out with or without weld material and with or without the melting of the objects <NUM> to be welded. On the other hand, the welding process can also be used for repairing a single object <NUM>.

In particular, the objects <NUM> can be made, for example, of one or more metallic, ceramic or polymeric materials.

In the non-limiting embodiment shown, the welding workstation <NUM> is specifically used for the welding in the jewelery field. Consequently, the objects <NUM> can be made of precious or semi-precious materials and comprise precious stones or other minerals.

Alternatively, the welding workstation <NUM> is used in the prosthodontics/orthodontic fields, for example, for welding prostheses and hooks on skeletons; for jointing bridges, crowns, hooks or attachments; for correcting founding defects or for repairing prostheses.

The welding workstation <NUM> comprises a welding device <NUM> adapted to provide the necessary heat and/or pressure for jointing the objects <NUM> and a vision system <NUM> configured to show the objects <NUM> during the welding process to an operator.

According to the present invention, the welding device <NUM> comprises a laser source.

In particular, manual welding means a welding process that requires the manual intervention of an operator. However, such welding process could be partially automated. In the embodiment shown, such manual intervention consists in handling the objects <NUM> to be welded with respect to the laser source of the welding device <NUM>. Alternatively or additionally, the manual intervention can consist, for example, in handling the welding device <NUM> or the weld material.

The welding workstation <NUM> further comprises a process chamber <NUM> within which the welding process of the objects <NUM> is carried out by means of the welding device <NUM>.

The process chamber <NUM> comprises, in a known manner, a work platform <NUM>, a nozzle <NUM> for inletting protective gases (argon, helium, carbon dioxide, nitrogen, etc.) and an extractor <NUM> for extracting the welding fumes.

In the embodiment shown, the process chamber <NUM> is closed by a lid <NUM> and comprises, in a known manner, at least one opening <NUM> shaped for the insertion of the hands of the operator (<FIG>). Otherwise, the process chamber <NUM> could be open, i.e. not comprise the lid <NUM>.

The vision system <NUM> comprises, in turn, an image acquisition device <NUM> and a viewer device <NUM> wearable by the operator and configured to show the images captured by the image acquisition device <NUM> to the operator.

In particular, the vision system <NUM> is configured to show the objects <NUM> arranged inside the process chamber <NUM> during the welding process to the operator.

The image acquisition device <NUM> and the wearable viewer device <NUM> further define a vision kit <NUM> (aspect not covered by the present invention) installable also on existing welding workstations.

Specifically, the image acquisition device <NUM> is a digital microscope or a video camera capable of capturing highly magnified images. In the case of existing welding workstations provided with a microscope, the video camera can be inserted in place of an eyepiece of the microscope.

Preferably, the image acquisition device <NUM> has a variable magnifying capacity superimposable to that of the optical microscopes.

The image acquisition device <NUM> is positioned at least partially inside the process chamber <NUM>. The image acquisition device <NUM> has an objective - not shown - arranged inside the process chamber <NUM>.

Alternatively, the image acquisition device <NUM> can be positioned outside the process chamber <NUM> so as to be able to film the objects <NUM> inside the chamber <NUM> (for example, through a transparent portion of the lid <NUM>).

According to the present invention, the objective is further arranged coaxially to the laser source of the welding device <NUM> and, in particular, to the laser beam. This enables the operator to comfortably observe the points of the objects <NUM> to be invested with the laser radiation.

The image acquisition device <NUM> and the viewer device <NUM> are electrically connected to each other. In particular, they can be connected by means of a wired connection or, alternatively, by means of an electro-magnetic connection (for example, Bluetooth, infrared rays, radio waves, etc.).

In particular, the viewer device <NUM> comprises augmented reality glasses.

Such glasses comprise, in turn, a mount 6a and two lens elements 6b carried by the mount 6a. In particular, each lens element 6b is a screen, on which the images captured by the image acquisition device <NUM> are reproduced.

Similarly to the reading glasses, each lens element 6b is worn so as to be arranged in proximity of a respective eye of the operator.

Furthermore, the lens elements 6b can be arranged in a raised and peripheral position with respect to the field of view of the operator (as illustrated by the broken line in <FIG>). In this manner, the operator can stop looking at the images reproduced by the lens elements 6b without having to take off the viewer device <NUM>.

Specifically, the lens elements 6b can be shifted with respect to the mount 6a up to being arranged in a raised position. More specifically, the lens elements 6b can be rotated with respect to the mount 6a around an axis parallel to the ground, i.e. horizontal with respect to the face of the operator.

The viewer device <NUM> further comprises a covering - not illustrated - removably couplable to the augmented reality glasses and, in particular, to the lens elements 6b on the opposite side of the eyes of the operator. Specifically, the lens elements 6b are transparent and the covering is opaque and its color is dark.

More specifically, the coupling of the covering to the lens elements 6b, improves the vision of the images reproduced by the lens elements 6b, since the covering acts as background for the images. Vice versa, when the covering is uncoupled from the lens elements 6b, the lens elements 6b - which are transparent - enable the operator to observe the space surrounding and outside the process chamber <NUM>, without having to take off the augmented reality glasses.

By way of example, the covering is couplable to the augmented reality glasses by means of a magnetic connection.

Preferably, the two lens elements 6b enable the operator to obtain a stereoscopic vision of the images of the process chamber <NUM>.

Furthermore, as illustrated in <FIG>, the viewer device <NUM> is wearable in addition to possible reading glasses worn by the operator.

The viewer device <NUM> can also be easily adjusted with the aim to correct any vision anomalies of the operator.

The welding workstation further comprises an electronic control unit <NUM> (schematically illustrated in <FIG>) electrically connected to the welding device <NUM> for controlling the process parameters thereof. The electronic control unit <NUM> is also electrically connected to the viewer device <NUM>.

The electronic control unit <NUM> and the viewer device <NUM> are electrically connected by means of a wired connection or an electro-magnetic connection.

In particular, the viewer device <NUM> is configured to receive a signal associated with the values of the process parameters transmitted by the electronic control unit <NUM> and to enable the operator to view such parameters while carrying out the process. Specifically, each of the lens elements 6b can reproduce the values of such parameters in real time.

As the welding device <NUM> comprises, according to the present invention, a laser source, the process parameters controllable by means of the electronic control unit <NUM> can comprise one or more between, for example, the frequency and/or the power of the laser beam, the dimension of the focal spot, the welding speed, the focusing position.

The welding workstation <NUM> also comprises a process parameters adjustment device <NUM> electrically and operatively connected to the electronic control unit <NUM> for adjusting the process parameters.

In the embodiment shown, the process parameters adjustment device <NUM> is a screen <NUM> arranged outside the process chamber <NUM> and not wearable. Alternatively, the process parameters adjustment device <NUM> could be a joystick or a pedal operable by the operator.

According to a further embodiment, the process parameters adjustment device <NUM> could be integrated in the viewer device <NUM>. In such case, the operator could adjust the process parameters by means of the process parameters adjustment device <NUM>, for example through several push buttons positioned on the viewer device <NUM> or a vocal command.

Specifically, according to such further embodiment, the process parameters adjustment device <NUM> comprises a microphone - not illustrated - configured to receive a message uttered by the operator. Additionally, the process parameters adjustment device <NUM> is configured to transmit such message to the electronic control unit <NUM>. The electronic control unit <NUM>, in turn, is programmed to interpret the message uttered by the operator and consequently adjust the process parameters.

In particular, the microphone of the process parameters adjustment device <NUM> could be arranged at the viewer device <NUM>.

Furthermore, the image acquisition device <NUM> is configured to simultaneously transmit the captured images to more than one viewer device <NUM> and/or to more external screens <NUM>. Such further viewer devices <NUM> could be not placed in the workplace.

The operation of the welding workstation <NUM> is the following.

In use, the operator wears the viewer device <NUM> on his/her face, so that the two lens elements 6b are positioned at the eyes. Therefore, the operator can observe the images of the objects <NUM> to be welded captured by the image acquisition device <NUM> in a stereoscopic manner. In particular, the image acquisition device <NUM> captures the images of the inside of the process chamber <NUM>.

Subsequently, the operator inserts his/her hands and the objects <NUM> to be welded in the process chamber <NUM> through the openings <NUM> (<FIG>).

At this point, the operator, viewing the objects <NUM> to be welded through the viewer device <NUM>, moves them in the desired positions, with the aim for them to be invested by the laser radiation of the welding device <NUM> and to thus make the weld.

During the whole welding process, the operator can freely rotate his/her head or change his/her posture still being able to observe the objects <NUM> during the welding process. Therefore, if the operator continues to keep his/her hands inside the process chamber <NUM> through the openings <NUM>, he/she can continue to carry out the welding in an ergonomic position.

During the process, the process parameters transmitted to the viewer device <NUM> by the electronic control unit <NUM> are shown to the operator on the lens elements 6b. Consequently, the operator can adjust such process parameters by means of the process parameters adjustment device <NUM>.

Specifically, according to an embodiment not illustrated, the operator can adjust the process parameters by means of the vocal command device. More specifically, the operator utters a message relative to the adjustment of one or more process parameters. The message is thus detected by the microphone of the process parameters adjustment device <NUM> and transmitted to the control unit <NUM>, which interprets the message and adjusts the one or the more process parameters selected depending on the information contained in the message.

The present invention also concerns a method of vision of manual welding operations on the welding workstation <NUM>. Specifically, the vision method comprises the steps of i) capturing the images of the objects <NUM> to be welded through the image acquisition device <NUM> during the welding operations and ii) transmitting the images captured by the image acquisition device <NUM> to the viewer device <NUM>, which is worn by the operator, with the aim to show the latter the captured images of the objects <NUM> to be welded during the welding operations.

More specifically, the transmission of the images which is performed in the step ii) is simultaneous with the capturing of the images which is performed in the step i). In this manner, the operator can view in real time the objects <NUM> subjected to the welding operations through the viewer device <NUM>.

The present invention also concerns a method of updating an existing welding workstation for carrying out manual welding operations comprising:.

The method comprises the steps of i) installing in the workstation, i.e. mounting on a portion of the workstation, an image acquisition device <NUM>, in addition to the microscope present in the workstation, configured to capture images of the objects <NUM> to be welded during the welding operations in the existing welding workstation; and ii) electrically connecting a viewer device <NUM> wearable by an operator carrying out the manual welding operations to the image acquisition device <NUM>.

Specifically, the image acquisition device <NUM> comprises a video camera, an objective which is positioned at an eyepiece of said microscope of said workstation. More specifically, the objective of the video camera is positioned at the eyepiece, after removing the lens of the eyepiece of the microscope closest to said eyepiece.

Based on the foregoing, the advantages of the welding workstation <NUM>, of the kit <NUM> and of the method according to the invention are apparent.

Since the vision system <NUM> comprises the image acquisition device <NUM> and the wearable viewer device <NUM>, which shows the captured images of the objects <NUM> to be welded to the operator, the operator can freely change his/her posture while carrying out the welding. In fact, the operator is not obliged to remain in a fixed position with his/her eyes in contact with the eyepieces of a microscope or in visual contact with a non-wearable and fixed screen. On the contrary, the operator can, for example, freely rotate his/her head without losing the visual contact with the images captured by the image acquisition device <NUM> or sit with his/her back straight, without having to curve over the eyepieces of the microscope. Consequently, the ergonomic trim of the whole welding workstation <NUM> is significantly improved. It has been observed, in particular, that a greater comfort of the operator of the welding workstation <NUM> also corresponds to a greater level of productivity.

Moreover, since the images of the objects <NUM> during the welding operation are shown to the operator through the viewer device <NUM> and not through a non-wearable fixed screen, the risk of glare due to the light sources present in the surrounding environment is minimized.

It has been further observed that the visibility of the work area inside the process chamber <NUM> is generally improved with respect to the visibility obtainable through a non-wearable fixed screen. In fact, the operator obtains a three-dimensional perception of the objects <NUM> to be welded comparable to that obtainable with the eyepieces of a microscope.

The embodiment wherein the viewer device <NUM> is electrically connected to the image acquisition device <NUM> by means of an electro-magnetic connection is even more advantageous, since the operator is not constrained in his/her movements by the length of the wired connection.

It is possible to draw advantage also from the fact that the image acquisition device <NUM> can be electrically connected to a plurality of viewer devices <NUM> and/or of screens <NUM>. In fact, in this manner, the carrying out of the process can be projected, for example, for educational purposes.

Moreover, since the viewer device <NUM> is wearable in addition to possible reading glasses worn by the operator, the operator is not obliged to take off his/her reading glasses before wearing the viewer device <NUM>. Consequently, the vision system <NUM> is remarkably more ergonomic than the known vision systems. In fact, the operator that wears reading glasses will not be obliged to adjust the focusing settings of the viewer device <NUM> for adapting it to his/her sight.

Furthermore, the embodiment not illustrated wherein the process parameters adjustment device <NUM> comprises a vocal command device is particularly advantageous, since the operator can adjust the process parameters without having to interrupt the vision of the inside of the process chamber <NUM> and without having to use his/her hands.

Claim 1:
Welding workstation (<NUM>) for carrying out manual welding operations comprising:
- a welding device (<NUM>) adapted to provide the necessary heat and/or pressure for welding objects (<NUM>);
characterised in that:
said welding device (<NUM>) comprising a laser source;
and in that the welding workstation (<NUM>) further comprises:
- a vision system (<NUM>) configured to show said objects (<NUM>) during the welding operations to an operator carrying out the welding operations;
said vision system (<NUM>) comprising, in turn:
- image acquisition means (<NUM>) configured to capture images of said objects (<NUM>) during the welding operations; and
- viewer means (<NUM>) wearable by the operator and electrically connected to said image acquisition means (<NUM>); said viewer means (<NUM>) being configured to show the images captured by said image acquisition means (<NUM>) to the operator;
wherein said image acquisition means (<NUM>) comprise an objective arranged coaxially to said laser source.