EP3868515B1

EP3868515B1 - Tool for hose clamps

Info

Publication number: EP3868515B1
Application number: EP21154891.2A
Authority: EP
Inventors: Claudio RIVA
Original assignee: Sofca Srl
Current assignee: Sofca Srl
Priority date: 2020-02-04
Filing date: 2021-02-03
Publication date: 2023-09-06
Anticipated expiration: 2041-02-03
Also published as: IT202000002128A1; EP3862136A1; EP3868515A1

Description

This invention generally relates to an intelligent tool for mounting hose clamps on a tube, a conduit or similar structure.
Generally, a known tool for mounting clamps on tubes comprises: a power source adapted to supply electrical or pneumatic power, a working head, adapted to use this power to move between an open configuration, in which it is suitable to receive a hose clamp, and a closed configuration, in which it is suitable to clamp said hose clamp on a tube; and transmission means interposed between said power source and said working head, and adapted to transmit said power to the working head to drive its movement between the open configuration and the closed configuration.
Tools for mounting hose clamps are known from prior art documents EP 3,616,845 A1 , EP 1,103,349 A2 , US 6,240,626 B1 , EP 3,075,492 A1 , upon which the preamble of claim 1 is based, and US 2006/272381 A1 .
The tools for mounting hose clamps according to the prior art have various problems.
First, it is necessary to supply electrical power to the motor of the tool via a power cable, or it is necessary to supply pneumatic power to the tool via a pneumatic conduit. In any case, the presence of electric power supply cables or pneumatic power supply hoses, although often made in flexible form, constitutes a problem in terms of space and safety for the operator using the tool.
Furthermore, in tools according to the prior art, it is not possible to precisely control the clamping process, and therefore there is a risk of the hose clamps being clamped or mounted incorrectly, or of hose clamps of an unsuitable type or size being mounted on a tube, or of the operator being injured while using the tool.
Moreover, generally the tools according to the prior art are specifically made for use with a specific type or size of hose clamps, and therefore cannot be used to mount hose clamps of different types or sizes.
Lastly, the known tools are particularly inconvenient when the clamping of the hose clamp must be effected with a certain inclination by the operator.
The object of this invention is to provide a tool for mounting hose clamps which does not suffer from the drawbacks of the prior art, and which has a better durability and reliability.
This and other objects are fully achieved according to this invention by a tool as defined in the appended independent claim 1 and the method of definition of a program according to claim 11.
Advantageous embodiments of the invention are specified in the dependent claims, the content of which is to be understood as an integral and integrating part of the following description.
In short, the invention is based on the idea of constructing a tool for mounting hose clamps on a tube, comprising:

an electric motor adapted to generate a driving torque;
a working head, removably mounted on the tool, and adapted to move between an open configuration, in which it is adapted to receive a hose clamp, and a closed configuration, in which it is adapted to clamp said hose clamp onto a tube;
transmission means, interposed between said electric motor and said working head, adapted to transmit said driving torque generated by the electric motor to said working head to drive the movement of the working head between the open configuration and the closed configuration;
a magnetic element and proximity sensing means, the proximity sensing means being adapted to generate a proximity signal when the relative distance between the magnetic element and the proximity sensing means is less than a predetermined distance of measure; and
an electronic control unit configured to control the driving torque generated by the electric motor as a function of said proximity signal generated by the proximity sensing means; the transmission means comprising a worm screw and a transmission shaft, extending along a longitudinal axis, wherein the worm screw is adapted to convert a rotary motion generated by the electric motor into a translational motion along said longitudinal axis of said transmission shaft, said translational motion being able to be transmitted to the working head;
the transmission means further comprising a thrust element adapted to transmit the translational motion of said transmission shaft to the working head; and in that the tool further comprises force sensing means adapted to measure the force transmitted by the transmission shaft to the thrust element and to transmit the result of this measurement to the electronic control unit.

Preferably, the tool further comprises at least one battery adapted to supply electric power to the electric motor.
Advantageously, the working head is mounted rotatably with respect to a longitudinal axis of the tool.
Preferably, the magnetic element is arranged integral with the transmission means and adapted to be drawn by said transmission means between a first position, wherein the working head is in the open configuration, and a second position, wherein the working head is in the closed configuration.
Preferably, furthermore, the proximity sensing means comprise a pair of sensors, in particular a first proximity sensor and a second proximity sensor, each adapted to generate a respective proximity signal when the relative distance between the magnetic element and, respectively, the first proximity sensor or the second proximity sensor, is less than a predetermined distance of measure.
Advantageously, furthermore, the tool further comprises a pair of control buttons adapted to transmit a command signal to the electronic control unit, the pair of control buttons being arranged and made in such a way that an operator must use both hands to activate them, or to press or squeeze them in a manner known per se, simultaneously.
Using such a tool, it is possible to overcome the drawbacks of the prior art cited above, and to provide a more reliable, customizable, and safe mounting procedure.
Further features and advantages of this invention will be clarified by the detailed description that follows, given purely by way of non-limiting example in reference to the accompanying drawings, wherein:

Fig. 1 is a bottom view of a tool for mounting hose clamps according to an embodiment of the invention;
Fig. 2 is a side sectional view of the tool of Fig. 1, on a section plane perpendicular to the plane of Fig. 1 and passing through the center of the tool;
Fig. 3a, 3b and 3c show a detail of the tool of Fig. 1, respectively in an open configuration, in an intermediate configuration, and in a closed configuration, on a section plane parallel to the plane of Fig. 1 and passing through the center of the tool;
Fig. 4 is a schematic view of a mounting system comprising the tool of Fig. 1, a command control box, and a data management system;
Fig. 5 is a side view on a section plane parallel to the plane of Fig. 1 and passing through the tool center of a tool according to a further embodiment of the invention; and
Fig. 6 is a detailed view of a component of the tool of Fig. 5.

With reference to the figures, a tool for mounting hose clamps according to this invention is generally indicated with 10.
The tool 10 essentially comprises an electric motor 12, a working head 16, a magnetic element 18, proximity sensing means 20, force sensing means 27, an electronic control unit 22, and a frame 24 adapted to support the components of the tool 10.
The electric motor 12 is fixed to the frame 24 by means of a flange of the motor 24b and is adapted to generate a driving torque when powered and when so commanded by the electronic control unit 22. For example, an electric motor 12 suitable for the tool 10 according to the invention may have a power between a few tens of W and about 200 W, for example a power of about 100 W. The dimensions and numerical parameters reported here are purely illustrative and should not be interpreted in a limiting manner.
The tool 10 preferably further comprises a battery 14. The battery 14 is adapted to supply electric power to the electric motor 12, and is preferably provided as a rechargeable battery, being therefore arranged for recharging through a dedicated electric connector. Alternatively, the battery 14 may be provided as a replaceable battery. For example, a battery 14 suitable for the tool 10 according to the invention may have a capacity between a few tenths of Ah and about 2 Ah, for example a capacity of about 1.3 Ah, and a voltage, for example, of 18 V.
In an alternative embodiment, the tool 10 is powered by means of an electric power supply cable, in a manner known per se.
The working head 16 is mounted on the tool 10 in a removable manner, i.e., in a separable way, i.e., able to be disassembled from the frame 24, so as to be able to remove the working head 16 for cleaning or maintenance operations, or even so that it may be replaced entirely in case of damage, or if it is not suitable for the type of hose clamp to be mounted. The connection between the working head 16 and the frame 24 may be provided in different forms, for example through a snap or bayonet connection, or through a threaded connection, or in any other way suitable for easily removing or replacing the working head 16.
In a preferable embodiment of the invention shown in Fig. 5, the working head 16 is mounted rotatably, i.e., so that it may be rotated about a longitudinal axis x of the tool 10. Preferably, the longitudinal axis x is the extension axis of a transmission shaft 17 adapted to transmit the translational motion to the working head 16, as will be explained later. For this purpose, the connection between the working head 16 and the rest of the tool 10 may be made by means of a threaded cap 21, with which a ring nut 23 is associated, screwed in the opposite direction with respect to the threaded cap 21, in such a way that the screwing of the working head 16 does not necessarily correspond to a variation of the axial position along the longitudinal axis x of the working head 16. The connection between the working head 16 and the rest of the tool 10 may naturally be made in many equivalent ways, but it is preferably made in such a way as to allow an operator to manually rotate the working head 16 about the longitudinal axis x by means of a manually applicable force, and in such a way that the working head 16 maintains the angular position thus determined without the need for further mechanisms.
In this embodiment, the tool 10 also advantageously comprises angular position sensing means 13. These angular position sensing means 13 are adapted to measure, determine or detect the angular position of the working head 16 about the longitudinal axis x, from an angular reference position. The result of this detection is then transmitted to the electronic control unit 22. In an exemplifying embodiment, the angular position sensing means 13 comprise a disc 13a and an optical sensor 13b. The disc 13a is mounted so as to rotate about the longitudinal axis x integrally with the working head 16, and has a plurality of notches arranged, preferably, in proximity to a radially external edge of the disc 13a, in fixed or predetermined angular positions and preferably equally spaced; for example, the disc 13a has 360 notches, arranged equally spaced angularly, each adapted to identify an angular position of, respectively, 1°, 2°, 3° and so on. To facilitate the rotation of the working head 16, the disc 13a may advantageously be made of bronze, since this material has a relatively low friction coefficient. The optical sensor 13b is arranged to be able to detect the notches of the disc 13a or the passage of these notches of the disc 13a, and to count the number of passages of these notches; in this way, starting from a known position, it is possible to determine the angular position of the working head 16.
The working head 16 is adapted to move between an open configuration, in which it is adapted to receive a hose clamp, and a closed configuration, in which it is adapted to clamp said clamp onto a tube.
In particular, the working head 16 may comprise a pair of clamping elements 26, rotatably mounted, each on a respective fulcrum F. The clamping elements 26 are made in such a way as to have, on one side, a shape adapted to support and clamp a hose clamp, for example by means of two respective clamps 28, and, on the other side, so as to be moved between the open configuration and the closed configuration, for example by means of an internal profile 30 with a curved or beveled shape, as shown in Fig. 3a, 3b and 3c.
The working head 16, as mentioned, is adapted to move between the open configuration-as shown in Fig. 3a-that is, the configuration wherein it is possible to insert a hose clamp to be mounted, wherein the clamping elements 26 have a maximum relative distance from each other, and the closed configuration-as shown in Fig. 3c-that is, the configuration wherein the hose clamp is clamped on the tube, wherein the clamping elements 26 have a minimum relative distance from each other, passing through a plurality of intermediate configurations, one of which being shown in Fig. 3b.
The working head 16 is mounted so as to remain normally in the open configuration, for example by means of a torsion spring or other known means.
The movement of the working head 16 from the open to the closed configuration and vice versa is driven by the driving torque generated by the electric motor 12. This driving torque is transmitted to the working head 16 through the transmission means 32, interposed between the electric motor 12 and the working head 16, in a manner known per se.
According to a preferred embodiment of the invention, between the electric motor 12 and the transmission means 32 there is also arranged a reduction mechanism, known per se, adapted to multiply suitably the driving torque generated by the electric motor 12 according to the dimensional requirements and design of the tool 10.
According to the invention, the transmission means 32 comprise a worm screw 34, so as to be able to reduce the radial dimensions thereof to the minimum and to be able to convert a rotary motion generated by the electric motor 12 into an axial motion adapted to move the working head 16 between open and closed configurations. The transmission means 32 further comprise a transmission shaft 17 which extends along said longitudinal axis x, and the worm screw 34 is adapted to convert the rotary motion generated by the electric motor 12 into a translational motion along said longitudinal axis x of said transmission shaft 17, the translational motion of the transmission shaft 17 being transmitted to the working head 16.
The transmission means 32 further comprise a thrust element 36 adapted to contact the internal profile 30 of the pair of clamping elements 26, so as to push the working head from the open to the closed configuration. In particular, the thrust element 36 may have a rod shape and be axially slidable, receiving the axial motion transmitted by the worm screw 34.
According to the invention, the tool 10 further comprises force-sensing means 27, adapted to measure the force transmitted to the thrust element 36, by the transmission shaft 17 or by a member interposed between them. The result of the measurement is then transmitted to the electronic control unit 22. To this end, the force sensing means 27 are preferably mounted integral with the transmission shaft 17. As clearly shown in Fig. 5 and 6, the force sensing means 27 may, in a preferable embodiment, comprise a load cell 27a equipped with a plurality of strain gauges 27b, for example four strain gauges 27b arranged equally spaced angularly. By virtue of such an arrangement, the force sensing means 27 are able to detect or measure the force imparted to the thrust element 36, in the moment prior to the application of the load on the hose clamp, such force, although not directly equal to the force applied by the working head 16 to the hose clamp, is in any case attributable to such a force, with an excellent approximation, by means of suitable algorithms based on experimental tests known per se.
As mentioned previously, the tool 10 further comprises a magnetic element 18 and proximity sensing means 20 adapted to generate a proximity signal when the relative distance between the magnetic element 18 and the proximity sensing means 20 is less than a predetermined distance of measure. The predetermined distance of measure depends on the sensitivity of the proximity sensing means 20 used and corresponds substantially to the distance below which the proximity sensing means 20 are adapted to detect the proximity of an object.
According to a first embodiment, the magnetic element 18 is arranged integrally with the transmission means 32, while the proximity sensing means 20 are mounted integrally with the frame 24. In an alternative but clearly equivalent embodiment of the invention, the configuration of the magnetic element 18 and of the proximity sensing means 20 is inverted; that is, the proximity sensing means 20 are mounted integral with the transmission means 32 and the magnetic element 18 is permanently mounted on the frame 24. Hereinafter, for the sake of brevity, only the first of these two alternative embodiments will be described in detail, it being understood that the alternative but equivalent embodiment is also included in the scope of the invention.
The magnetic element 18 may be formed, for example, of a simple bushing or a rod made of ferromagnetic or permanently magnetized material. The magnetic element 18 is drawn by the transmission means 32 throughout the whole of the movement between two extreme positions, in particular between a first position, wherein the transmission means 32 are in such a configuration that the working head 16 is in the open configuration, and a second position, wherein the transmission means 32 are in a configuration such that the working head 16 is in the closed configuration. Substantially, the position of the magnetic element 18 depends on the configuration of the working head 16, and, in particular, the first position and the second position of the magnetic element 18 correspond to the two open and closed configurations, respectively.
The proximity sensing means 20 may be arranged on the frame 24 of the tool 10, whereby they may generate a proximity signal as a function of the relative position of the magnetic element 18 relative to the proximity sensing means 20. In particular, when the relative distance between the proximity sensing means 20 and the magnetic element 18 is less than a predetermined distance of measure, corresponding to the activation distance of the proximity sensing means 20, that is, the maximum distance below which the proximity sensing means 20 are activated, the proximity sensing means 20 generate a proximity signal and transmit it to the electronic control unit 22.
In particular, the proximity sensing means 20 may comprise induction sensors, or Hall effect sensors.
Preferably, according to an embodiment of the invention, the proximity sensing means 20 comprise a pair of sensors 20a and 20b, in particular a first proximity sensor 20a and a second proximity sensor 20b, each adapted to generate a relative proximity signal when the relative distance between the magnetic element 18 and, respectively, the first proximity sensor 20a or the second proximity sensor 20b is less than a predetermined distance of measure, that is, when the magnetic element 18 is in, respectively, said first or second position, and to transmit said proximity signal to the electronic control unit 22.
As the first or second position of the magnetic element 18 corresponds respectively to the open or closed configuration of the working head 16, the electronic control unit 22 may therefore determine whether the working head 16 is in the open or closed configuration according to how many and which proximity signals it receives, and control the generation of the driving torque by the electric motor 12, and therefore the movement of the working head 16 between the open configuration and the closed configuration and vice versa as a function of said proximity signal.
It is clear to those skilled in the art that the tool 10 may easily comprise both a rotatably mounted working head 16 and force sensing means 27 and/or proximity sensing means 20 since there are no objective difficulties in combining these features.
In particular, the electronic control unit 22 may also be configured to ignore a possible erroneous signal, as in the case in which two proximity signals indicating conflicting information are received.
To allow an operator to activate the tool 10, the tool 10 is also provided with a pair of control buttons 38, adapted to transmit a command signal to the electronic control unit 22. The pair of control buttons 38 is arranged and provided in such a way that an operator must use both hands to activate the control buttons 38 simultaneously. For example, it is possible to arrange the pair of control buttons 38 at a distance from each other greater than that which may commonly be reached with a single hand. Or it is also possible to make the pair of control buttons 38 so as to require a pressure force generally not obtainable with one hand, and as such, for example, to require the use of both thumbs of an operator's hands. In the preferable embodiment of the invention, the pair of buttons 38 is arranged on two opposite sides of the frame 24, to require an operator to use both hands to activate the pair of buttons 38 simultaneously, as shown in Fig. 2.
In a further embodiment, the tool 10 further comprises a light indicator, adapted to signal information to the operator; for example, a light indicator may be adapted to signal visually the outcome of the clamping operation of the hose clamps, or also to signal a charging condition of the battery 14 of the tool 10. In a preferred embodiment, the light indicator has two different indicator lights, in particular a first indicator light, for example a red light, adapted to light up in the event that the clamping operation of the hose clamps has not been completed correctly, and a second indicator light, for example a green light, adapted to light up if the clamping operation of the hose clamps has been completed correctly.
In a further embodiment, the light indicator is replaced or accompanied by a light indicator adapted to signal information to the operator by means of sound.
With reference in particular to Fig. 4, a mounting system 40 according to a further aspect of the invention comprises the tool 10 for mounting hose clamps, a command control box 42, and, preferably, also a data management system 44.
The mounting system 40 is made in such a way as to allow data communication between the tool 10 and the command control box 42, preferably by means of wireless transceiver means 46, such as for example a Bluetooth or infrared or radio wave transmission system, and the command control box 42 is arranged to allow an operator to display information relating to the operation of the tool 10, such as the number of correctly mounted hose clamps, the charge level of the battery 14 of the tool 10, the torque generated by the electric motor 12, or a malfunction indicator for the tool 10 or one of the components thereof.
For this purpose, the command control box 42 is equipped with a display screen 48, and a keypad 50 for controlling the parameters of the display screen 48, as well as for entering parameters, data, programs, commands, or instructions to be transmitted to the tool 10. In a preferable embodiment, the command control box 42 is equipped with a touch screen adapted to perform both the functions of the display screen 48 and the functions of the keypad 50, in a manner known per se.
In a preferred embodiment of the mounting system 40 according to the invention, the same command control box 42 is arranged to communicate with a plurality of tools 10, as well as to interface with the data management system 44, for example a data management system in a company server or in the cloud, for example by means of wireless transceiving means 46, such as for example a Bluetooth or infrared or radio wave transmission system, or, preferably, by means of wired data transmission. In this way, the command control box 42 allows the data stored in each tool 10 to be transmitted to the same data management system 44 and analyzed jointly.
The operation of the tool 10 according to the invention and of the related mounting system 40 is as follows.
The operator initially checks the available program options and sets a predefined clamping program via the command control box 42 and, possibly, customizes the parameters of the selected clamping program. The clamping program may be selected from a plurality of predefined programs, stored or defined by the user each time, or, again, self-defined by the command control box 42 through a self-learning function, for example through so-called deep learning algorithms, following a series of preliminary trial, training or test operating cycles. The clamping programs may include various parameters, such as the number of hose clamps to be mounted, the size thereof, as well as a plurality of physical control parameters to be checked during the execution of the clamping program or at the end thereof, such as for example the time interval wherein the electric motor 12 delivers driving torque or the evolution over time of the torque delivered by the electric motor 12, or an internal temperature of the tool 10 not to be exceeded. In particular, the electronic control unit 22 may store a torque-stroke characteristic of the electric motor 12 by means of a self-learning procedure, in which, before the operative use of the tool 10, the tool 10 is used to perform a series of preliminary trial, training or test operating cycles, by means of which the electronic control unit 22 may extrapolate a torque-stroke characteristic of the electric motor 12 and store it, or determine a range of acceptable values of the force transmitted to the thrust member 36 and a range of acceptable values of the stroke of the transmission shaft 17 and store this information. Finally, a clamping program may comprise clamping a single clamp or even a plurality of hose clamps.
Thus, the operator positions a hose clamp to be mounted so that it is supported by the working head 16 in order that it may be clamped on a tube. In this phase, the working head 16 is in the open configuration, so as to be able to accommodate the hose clamp.
The electronic control unit 22 is preferably configured to control the generation of the driving torque by the electric motor 12 according to a control logic comprising the following steps:

when only one of the buttons of the pair of control buttons 38 is activated, the electronic control unit 22 commands a first driving torque to be generated by the electric motor 12;
when both buttons of the pair of control buttons 38 are activated, the electronic control unit 22 commands a second driving torque to be generated by the electric motor 12, wherein the second driving torque is greater than the first driving torque.

In this way, when the operator starts a clamping cycle by activating, i.e., pressing, one of the control buttons 38, the working head 16 begins to move from the open configuration to the closed configuration with a minimum force, avoiding risks or dangers for the operator. Then, when the operator activates or presses the other of the two control buttons 38 with the other hand, the electronic control unit 22 commands the actual clamping cycle to start; this clamping cycle is completed only if both control buttons 38 are kept activated or pressed.
At this point, the electronic control unit 22 commands the start of the clamping cycle, first by commanding the electric motor 12 to activate and, therefore, a driving torque to be generated, and by regulating the driving torque generated by controlling the relative critical parameters, such as, for example, the stroke, the current used by the electric motor 12, and, possibly, measuring indirectly the driving torque or measuring the force transmitted to the thrust element 36 by means of said force sensing means 27, preferably applied on the transmission means 32, for example on the transmission shaft 17. The electric motor 12, therefore, begins to deliver the driving torque, which is first multiplied by the reduction mechanism and then transmitted through the transmission means 32 to the working head 16, and in particular is converted by the worm screw 34 into an axial motion and transmitted through the thrust element 36 to the clamping elements 26.
During this movement, wherein the working head 16 passes from the open configuration to the closed configuration, thus clamping the hose clamp, the magnetic element 18 moves integrally with the transmission means 32 from the first position to the second position (or, in an alternative embodiment not described in detail, the sensing means 20 move integrally with the transmission means 32). When it reaches the second position, that is, when the working head 16 has reached the closed configuration, and, therefore, the clamping process of the hose clamp is complete, the proximity sensing means 20 detect the proximity of the magnetic element 18; in particular, the second proximity sensor 20b detects that the magnetic element 18 has reached the second position and generates a proximity signal which is transmitted to the electronic control unit 22. Upon receiving this proximity signal, the electronic control unit 22 sends an end-of-cycle signal, i.e., it commands the inversion of the driving torque generated by the electric motor 12 and transmitted to the working head 16. Upon receiving an inverse driving torque, the working head 16 begins the movement to return from the closed configuration to the open configuration. When this movement is complete, the magnetic element 18, which continues to move integrally with the transmission means 32, returns to the first position, and is detected by the first proximity sensor 20a, which sends a respective proximity signal to the electronic control unit 22, signaling that the magnetic element 18 has reached the first position, that is, returned to the initial position, and thus it is possible to start a new mounting and clamping cycle.
The electronic control unit 22 may also be configured to check the correct operation of the tool 10 and to provide, at the end of the clamping cycle, the operator with a signal or information indicating the success or failure of the clamping operation, and indirectly of the mounting.
In particular, the electronic control unit 22 may, for example, increase a counter for each hose clamp mounted, and, therefore, for each clamping cycle carried out and successfully completed, and automatically command the generation of driving torque by the electric motor 12 to be interrupted upon reaching a pre-set or predefined or user-defined number of mounted hose clamps.
The electronic control unit 22 may also be programmed to lock the tool 10 in a safe condition for the operator at the end of the clamping cycle or of the plurality of mounting cycles provided in the defined clamping program.
Furthermore, the control unit 22 may be configured to verify the correct execution of a predefined clamping program comprising the clamping of one or more hose clamps by determining the number of correctly mounted hose clamps based on at least one of the following parameters: the presence of a proximity signal generated by the proximity sensing means 20 and the number of said proximity signals generated by the proximity sensing means 20.
Lastly, the control unit 22 may be configured to verify the correct execution of a predefined clamping program comprising clamping one or more hose clamps by means of a comparison of a target parameter of the predefined clamping program and at least one measured parameter indicative of at least one among: the presence of at least one proximity signal generated by the proximity sensing means 20, the number of said proximity signals generated by the proximity sensing means 20, a stored torque-stroke characteristic of the electric motor 12 or a range of acceptable values of the force transmitted to the thrust element 36 and a range of acceptable values of the stroke of the transmission shaft 17, the instantaneous driving torque generated by the electric motor 12, the angular position of the working head 16 about the longitudinal axis x with respect to a reference angular position, the evolution of the driving torque generated by the electric motor 12 within a predefined time interval, a time interval comprised between the reception of two consecutive proximity signals generated by the proximity sensing means 20, and a total time of generation of the driving torque of the electric motor 12.
The result of verifying the correct execution of the predefined clamping program may be communicated to the operator by means of the light indicator, for example by means of a first indicator light, for example a red light, adapted to light up if the verification has given a negative result, and a second indicator light, for example a green light, adapted to light up if the verification has a positive result.
In addition, the electronic control unit 22 may also be configured to verify the correct execution of a predefined clamping program comprising the clamping of one or more hose clamps by comparing a target parameter of the predefined clamping program and at least one parameter measured as explained above, both at the moment of clamping and immediately or shortly after the moment of clamping. In this case, in a particularly preferable embodiment, the electronic control unit 22 is configured to check that, at the time of clamping, the measured parameters, in particular the stroke and the force, substantially correspond to the target parameters of the predefined clamping program, or to those stored or predetermined, while in an instant immediately or shortly after the moment of clamping, the measured parameters, in particular the stroke and the force, substantially correspond to those congruent with the load-free working head 16, in the process of reopening.
Lastly, a method for mounting hose clamps on a tube with the tool 10 according to the claim 11 is also part of the invention, whereby the control unit 22 may verify the correct execution of a predefined clamping program comprising the clamping of one or more hose clamps or may verify the correct operation of the tool 10. As stated previously, in effect, before the operative use of the tool 10, the tool 10 may be used to carry out a series of preliminary trial, training or test operating cycles, through which the electronic control unit 22 may extrapolate a torque-stroke characteristic of the electric motor 12 or determine a range of acceptable force values and a range of acceptable stroke values and store such information.
This method comprises the steps of:

a) providing a tool 10 according to any of claims 1 to 8;
b) performing a plurality of clamping operations of hose clamps on a tube;
c) for each of the clamping operations of step b), measuring the force transmitted by the transmission shaft 17 to the thrust element 36 by means of said force sensing means 27 and determining, preferably by means of a keyed resolver on the transmission shaft 17 or on a drive shaft of the electric motor 12, the stroke of said transmission shaft 17 in its translational motion along said longitudinal axis x;
d) for each of the clamping operations of step b), evaluating whether the clamping operation is of acceptable quality or not, and discarding the force and stroke measurements of step c) relating to clamping operations of unacceptable quality;
e) by means of the electronic control unit 22, determining a range of acceptable force values and a range of acceptable stroke values using the force and stroke measurements of step c) relating to the clamping operations of acceptable quality, i.e., using the measurements of force and of stroke of step c) that have not been discarded.

In step c) the force transmitted by the transmission shaft 17 to the thrust element 36 through said force sensing means 27 and the stroke of said transmission shaft 17 in its translational motion along said longitudinal axis x are measured; these two values are in effect attributable, by means of algorithms known per se, to the force applied to the hose clamp by the working head 16 and to the clamping stroke of the hose clamp following the clamping operation, respectively.
According to advantageous embodiments, the method may also comprise the step of modifying the range of acceptable force values and the range of acceptable stroke values determined in step e) through a direct command of an operator of the tool 10, for example by means of a manual command given to the electronic control unit 22 via the command control box 42. For example, an operator may modify that range by enlarging it by a certain fixed percentage starting from both ends of the range or by reducing it proportionally in the same way.
Preferably, step e) of determining the range of acceptable force values and the range of acceptable stroke values comprises the use of predetermined force and/or stroke values, for example pre-stored in the electronic control unit 22 or in the command control box 42.
This step e) may make use of conventional algorithms and/or artificial intelligence or self-learning algorithms to determine, i.e., extrapolate, from the force and stroke measurements relating to the clamping operations of acceptable quality, a range of acceptable force values and a range of acceptable stroke values.
In a way that is self-evident, the evaluation of the clamping operation, i.e., of whether this operation is of acceptable quality or not, of step d) is carried out through the interaction of an operator of the tool 10 with the electronic control unit 22 and/or with the command control box 42. Obviously, this assessment is carried out by the specialized operator, preferably a technologist, i.e., a product quality expert or engineer, in consideration of target parameters of quality and acceptability of the hose clamp following the clamping operation about a tube.
As evident from the description provided above, a tool according to this invention provides several advantages.
First, due to the use of proximity sensing means and a magnetic element to determine the position of the transmission means and, therefore, the configuration of the working head, the tool according to this invention is more precise and therefore more reliable than known tools for mounting hose clamps.
Moreover, by using the electric power supply instead of the commonly used pneumatic one, it will be possible to avoid the accidental diffusion in the working environment of lubricated compressed air. Furthermore, in the preferable embodiment wherein the tool comprises an electric motor and a battery, the tool does not need to be powered by an electric power cable or by a pneumatic power hose, ensuring the operator greater freedom of movement and therefore making the mounting and clamping of the hose clamps safer and easier.
By virtue of the possibility of disassembling the working head from the tool frame, it is possible to remove or replace the working head, thus permitting the same tool to be used for mounting hose clamps of a different type or size and allowing the operator to choose the working head best adapted to the specific hose clamp.
The use of a pair of control buttons that may be activated only by using both hands adds an additional level of safety to the tool, avoiding accidental activation of the tool and making it impossible for an operator's hand to be too close to the working head as it moves from the open configuration to the closed configuration.
Lastly, the use of a tool according to the invention together with a command control box and, preferably, a data management system, allows for the operating parameters of one or more tools to be controlled remotely, as well as, by analyzing the data obtained from each clamping cycle, for any errors by the operator or the predefined clamping program to be identified.
Naturally, without prejudice to the principle of the invention, the embodiments and the details of construction may be widely varied with respect to that which has been described and illustrated purely by way of non-limiting example, without thereby departing from the scope of the invention defined in the appended claims.

Claims

Tool (10) for mounting hose clamps on a tube, comprising:
an electric motor (12) adapted to generate a driving torque;
a working head (16), removably mounted on the tool (10), and adapted to move between an open configuration, wherein it is adapted to accommodate a hose clamp, and a closed configuration, wherein it is adapted to clamp said hose clamp on the tube;

transmission means (32), interposed between said electric motor (12) and said working head (16), adapted to transmit said driving torque generated by the electric motor (12) to said working head (16) to drive the movement of the working head (16) between the open configuration and the closed configuration;

a magnetic element (18) and proximity sensing means (20), the proximity sensing means (20) being adapted to generate a proximity signal when the relative distance between the magnetic element (18) and the proximity sensing means (20) is less than a predetermined distance of measure; and

an electronic control unit (22) configured to control the driving torque generated by the electric motor (12) depending on said proximity signal generated by the proximity sensing means (20);

the transmission means (32) comprising a worm screw (34) and a transmission shaft (17), extending along a longitudinal axis (x), wherein the worm screw (34) is adapted to convert a rotary motion generated by the electric motor (12) into a translational motion along said longitudinal axis (x) of said transmission shaft (17), said translational motion being able to be transmitted to the working head (16);

the transmission means (32) further comprising a thrust element (36) adapted to transmit the translational motion of said transmission shaft (17) to the working head (16);

the tool (10) being characterised in that the tool (10) further comprises force sensing means (27) adapted to measure the force transmitted by the transmission shaft (17) to the thrust element (36) and to transmit the result of this measurement to the electronic control unit (22).
Tool according to claim 1, wherein the working head (16) is mounted rotatably about said longitudinal axis (x).
Tool according to claim 2, further comprising angular position sensing means (13) adapted to detect the angular position of the working head (16) about said longitudinal axis (x) with respect to a reference angular position and to transmit the result of such detection to the electronic control unit (22).
Tool according to claim 3, wherein the angular position sensing means (13) comprise a disc (13a), preferably of bronze, rotatably mounted about said longitudinal axis (x) integrally with the working head (16), and having a plurality of notches each arranged in a predetermined angular position, and an optical sensor (13b), adapted to detect the passage of said notches of the disc (13a) following a rotational movement of the disc (13a) and to count the number of these passages of said notches.
Tool according to any of the preceding claims, wherein the magnetic element (18) is arranged integral with the transmission means (32) and is adapted to be drawn by said transmission means (32) between a first position, in which the working head (16) is in the open configuration, and a second position, in which the working head (16) is in the closed configuration.
Tool according to any of the preceding claims, further comprising a pair of control buttons (38) adapted to transmit a control signal to the electronic control unit (22), wherein the pair of control buttons (38) is arranged and made in such a way that an operator must use both hands to activate them simultaneously, and/or wherein the two buttons of the pair of control buttons (38) are arranged on opposite sides of the tool (10).
Tool according to claim 6, wherein the electronic control unit (22) is configured to command the generation of the driving torque by the electric motor (12) according to a control logic comprising the following steps:
- when only one of the buttons of the pair of control buttons (38) is activated, the electronic control unit (22) commands the generation of a first driving torque by the electric motor (12);

- when both the buttons of the pair of control buttons (38) are activated, the electronic control unit (22) commands the generation of a second driving torque by the electric motor (12), the second driving torque being greater than the first driving torque.
Tool according to any of the preceding claims, wherein the electronic control unit (22) is further configured to check the correct execution of a predefined clamping program comprising clamping one or more hose clamps, and wherein the tool (10) further comprises a light indicator and/or a sound indicator adapted to signal the result of the check of the electronic control unit (22).
Assembly system (40) comprising a tool (10) according to any one of the preceding claims and a command control box (42), wherein the tool (10) further comprises wireless transceiving means (46) for receiving and transmitting data between the tool and the command control box (42), wherein the command control box (42) is arranged to allow an operator to see information relating to the operation of the tool (10), the information being at least one among: the number of hose clamps correctly clamped, the level of charge of the battery (14) of the tool (10), the torque generated by the electric motor (12), and a malfunction indicator of the tool (10).
Assembly system according to claim 9, further comprising a data management system (44), and wherein the command control box (42) is arranged to communicate with a plurality of tools (10) according to any one of claims from 1 to 8, and wherein the command control box (42) is further arranged to interface with the data management system (44), the data management system (44) being adapted to receive, store, and process data originating from at least one of the tools (10) of said plurality of tools (10).
A method for mounting hose clamps on a tube with the tool according to any of claims 1 to 8, comprising the steps of:
a) providing a tool (10) according to any of claims 1 to 8;

b) carrying out a plurality of clamping operations of hose clamps on a tube;

c) for each of the clamping operations of step b), measuring the force transmitted by the transmission shaft (17) to the thrust element (36) through said force sensing means (27) and determining the stroke of said drive shaft transmission (17) in its translational motion along said longitudinal axis (x);

d) for each of the clamping operations of step b), evaluating whether the clamping operation is of acceptable quality or not, and discarding the force and stroke measurements of step c) relating to clamping operations of unacceptable quality;

e) by means of the electronic control unit (22), determining a range of acceptable force values and a range of acceptable stroke values using the force and stroke measurements of step c) relating to the clamping operations of acceptable quality.
The method according to claim 11, further comprising the step of:
f) modifying the range of acceptable force values and the range of acceptable stroke values determined in step e) by means of a direct command of a tool operator (10).
The method according to claim 11 or 12, wherein the assessment of whether the clamping operation is of acceptable quality or not of step d) is carried out through the interaction of an operator of the tool (10) with the electronic control unit (22).