INJURY PREVENTION KIT INCLUDING A POWER TOOL AND A PORTABLE ACCESSORY

Abstract

An assembly comprising: - a power tool (100) having a drive means configured to move two blades or two jaws between an open position and a closed position, - a handheld accessory (200) intended to be worn by the user on a limb separate from the arm of the user holding the tool, - a means for estimating a representative value of the distance (D1) separating the handheld accessory and the power tool, as a function of the strength of a signal exchanged between a first antenna positioned on the power tool and a second antenna positioned on the handheld accessory, and in that the blades or jaws are moved or held in the open position unless each of the following conditions is met: - the representative value of the distance (D1) separating the handheld accessory and the power tool is less than a predetermined threshold, called the activation threshold,- The representative value of the distance (D1) separating the portable accessory and the power tool is greater than a predetermined threshold, called the safety threshold. Figure for the abbreviation: [Fig 1],

Description

Title of the invention: INJURY PREVENTION ASSEMBLY COMPRISING A PORTABLE ELECTRIC TOOL AND A WEARABLE ACCESSORY TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to an assembly, comprising a portable electric tool and a portable accessory, which allows the prevention of the risk of injuries and in particular the prevention of accidental injury to a member carrying the portable accessory by a blade or a jaw of said portable electric tool. In particular, the invention relates to an assembly comprising pruning shears and aims to prevent accidental mutilations. STATE OF THE ART

[0002] A power tool is a tool that can be handled by a user by hand and easily transported. A power tool is generally small in size and light in weight, for example less than 10 kilograms. A power tool is an electrical tool with elements that depend on an electrical power supply in the form of an associated battery present on the tool or powered by an electrical power cable connected to a mains power supply or to an independent power source.

[0003] More specifically, the present patent application relates to portable power tools comprising two blades, or two jaws, movable between an open position and a closed position. As non-limiting examples of tools belonging to this category, mention may be made of pruning shears, a cable cutting tool, a crimping tool, a punching tool or a tool for tightening shear screws.

[0004] These tools present, in the event of contact between the blades or jaws and a limb (arm or leg) of the user, significant risks of injury. For example, handling pruning shears held with one hand can very quickly lead to the amputation of a finger during a pruning operation in the context of a farm or domestic gardening.

[0005] Various safety systems exist to prevent the risk of injury. From the simplest, consisting of asking the user to keep his hand behind his back, or to attach it there, to more complex systems aimed at alerting of the proximity between the power tool and an accessory such as a bracelet or ring worn by the user on his free hand and / or stopping the blades in the event of proximity between the power tool and the accessory.

[0006] For example, the prior art knows the safety system for pruning shears described by patent application KR 10-2015-0035840 which comprises a ring configured to generate a magnetic field associated with a sensor positioned on the pruning shears to detect the magnetic field thus generated. This same document KR 10-2015-0035840 and document EP 3 967134 describe a bracelet or a ring equipped with a transmitter-receiver configured to exchange an electromagnetic wave of the radio signal type for example with a transmitter placed on pruning shears, so that a distance can be calculated between the transmitter-receiver on the pruning shears and on the bracelet and the motor of the pruning shears can be stopped as a safety measure when the bracelet and the pruning shears are too close to each other.The prior art also knows the patent application EP 3 967 134 A1 which describes a safety system for pruning shears comprising a conductive glove, an electrical voltage source and pruning shears configured so that, in the event of contact with the blades of the pruning shears and the conductive glove, the detection of an electric current allows the emergency stopping of the blades of the pruning shears.

[0007] It is emphasized, however, with regard to each of these systems that they tend to be ignored by certain users who may decide to simply not wear the accessory such as a bracelet or glove. In addition to the occurrence of injury, such negligence makes it difficult to allocate liability between the manufacturer of the power tool, the user and the user's employer, if applicable. OBJECTS OF THE INVENTION

[0008] The present invention aims to remedy all or part of the drawbacks of safety systems aimed at preventing injuries, and in particular preventing the risk of mutilation, when using a portable electric tool with blades or jaws.

[0009] To this end, according to a first object, the present invention aims at an assembly which comprises: - a power tool comprising a drive means configured to move two blades or two jaws between an open position and a closed position, - a portable accessory intended to be worn by the user on a limb separate from the arm of the user carrying the tool, - a means for estimating a value representative of the distance separating the portable accessory and the power tool, as a function of the strength of a signal exchanged between a first antenna positioned on the power tool and a second antenna positioned on the portable accessory and in which the blades or jaws are moved or held in the open position unless each of the following conditions are met: - the value representing the distance separating the portable accessory and the power tool is less than a predetermined threshold, called the activation threshold, - the representative value of the distance separating the portable accessory and the power tool is greater than a predetermined threshold, called the safety threshold.

[0010] For example, the activation threshold is a distance value between 1 meter and 2 meters, preferably between 1 meter and 1.5 meters. For example, the safety threshold is a distance value between 10 centimeters and 50 centimeters, preferably between 15 centimeters and 25 centimeters.

[0011] Under these normal conditions of use of the assembly which is the subject of the invention, the user carries a portable accessory, which is for example in the form of a glove. The portable accessory is intended to be worn on a limb separate from that used to handle the power tool. Preferably, the user carries the portable accessory on one hand and handles the power tool with the other hand.

[0012] The assembly which is the subject of the invention offers the advantage of ensuring that the member to be protected, for example the hand or arm of the user, is not too close to the source of danger, for example the blades of the power tool. If this distance is too short, below a safety threshold, the blades or jaws of the tool are open or kept open.

[0013] In addition, the assembly which is the subject of the invention offers the advantage of ensuring that the user uses the portable accessory. This verification is carried out according to the distance between the portable accessory and the power tool. If this distance is too great, beyond an activation threshold, the blades or jaws of the tool are opened or kept open.

[0014] In embodiments, the assembly comprises a verification means configured to estimate whether the portable accessory is being worn by a user. Advantageously, the blades or jaws are moved or kept in the open position unless the verification means estimates that the portable accessory is indeed being worn by a user.

[0015] Advantageously, the verification means comprises an accelerometer positioned on the portable accessory and the verification means verifies at regular intervals that the data recorded by said accelerometer are representative of active use of the portable accessory.

[0016] Thanks to these provisions, the assembly offers additional security ensuring that the user is carrying the portable accessory, i.e. that it is not simply placed nearby.

[0017] In embodiments, the assembly comprises a human-machine interface configured to allow the user to temporarily lift the safety so that the drive means can move the blades or jaws to a closed position without prior verification of the distance conditions described above. Preferably, the data relating to the authorization are recorded in a local or remote memory. These data correspond for example to the date and the time of authorization and the identity of the user who originated the authorization.

[0018] Thanks to these provisions, if the user so chooses, the security offered by the portable accessory can be temporarily lifted. This authorization is recorded in a memory, so that the manufacturer's liability can be released in the event of an accident.

[0019] In embodiments, the assembly comprises a means for emitting an audible or visual alarm positioned on the portable power tool or positioned on the portable accessory and said means emits an alarm when the value representative of the distance separating the first and second means for emitting or receiving an electromagnetic signal is less than a predetermined threshold, called the alert threshold.

[0020] Thanks to these provisions, an additional indication is communicated to the user by means of an alarm which is triggered when the power tool and the accessory are too close to each other, without however requiring the operation of the power tool to be blocked.

[0021] In embodiments, the first and second antennas are configured to exchange a signal transmitted in radio frequencies, in infrared or a signal according to the Bluetooth standard (registered trademark).

[0022] In embodiments, the first and second antennas are configured to exchange an ultra-wideband (UWB) type signal.

[0023] Thanks to these provisions, the implementation of a ULB signal allows an estimation of a value representative of the distance between the power tool and the accessory very quickly, with low latency, with high precision and causing low energy consumption.

[0024] In embodiments, the assembly comprises: - at least one additional portable accessory and - a means for estimating a value representative of the distance separating the additional portable accessory and the power tool, as a function of the strength of a signal exchanged between the first antenna positioned on the power tool and a third antenna positioned on the portable accessory and the blades or jaws are moved or held in the open position unless the following additional condition is satisfied: - the representative value of the distance separating the additional portable accessory and the power tool is greater than a predetermined threshold.

[0025] In a particularly advantageous manner, several different users can each carry a portable accessory, thus verifying that a safety distance is respected between the power tool and each of the users carrying the portable accessory.

[0026] In embodiments, the power tool is chosen from: pruning shears, a cable cutting tool, a crimping tool, a punching tool or a shear head screw tightening tool.

[0027] In embodiments, the wearable accessory is a bracelet, a ring, or a glove.

[0028] In embodiments, the power tool is a pruning shear comprising a counter-blade and a cutting blade made movable by a drive means comprising a brushless motor, a planetary reduction gear, a bevel or spiral bevel gear and a gear engaged with the cutting blade. BRIEF DESCRIPTION OF THE FIGURES

[0029] Other advantages, aims and particular characteristics of the invention will emerge from the following non-limiting description of at least one particular embodiment of the assembly which is the subject of the present invention, with reference to the appended drawings, in which [Fig.l] schematically represents a first particular embodiment of the assembly which is the subject of the present invention comprising a portable accessory in the form of a bracelet and a portable electric tool of the secateurs type, [Fig.2] represents, schematically, in perspective and in exploded view, the detail of the portable electric tool of the first embodiment, [Fig.3] represents, schematically, in perspective and in exploded view, the detail of the portable accessory of the first embodiment and [Fig.4] schematically represents a second particular embodiment of the assembly which is the subject of the present invention comprising a portable accessory in the form of a bracelet, a portable electric tool and an additional portable accessory.

[0030] In the attached figures, the numerical references refer to: 100 a pruning shears, a particular example of a portable power tool 1 and 2 two half-shells 3 a geared motor 4 a body 5 an electronic control card for the geared motor 6 a trigger 7 an electronic card associated with an antenna 8 a counter plate 9 a bearing 10 a nut 11 a roller thrust bearing 12 an axis 13 a second blade or counter-blade 14 a first blade or cutting blade 15 a pinion engaged with the first blade 16 a bevel gear 17 a bevel gear 18 an antenna associated with the electronic card 7 200 a bracelet, particular example of portable accessory 21 a second electronic card associated with an antenna 22 a battery 23 a cover 24 a second antenna 300 an additional bracelet DI a distance separating the pruning shears from the bracelet and D2 a distance separating the pruning shears from the additional bracelet. DETAILED DESCRIPTION OF THE INVENTION

[0031] The present description is given without limitation, each characteristic of an embodiment being able to be combined with any other characteristic of any other embodiment in an advantageous manner.

[0032] It should be noted, from now on, that figures 1 and 4 are not to scale that figures 2 and 3 are, each, to scale but, that between them, the scales vary.

[0033] In [Fig. 1], we observe a particular embodiment of an assembly which is the subject of the invention. Said assembly comprises a pruning shears 100 and a bracelet 200.

[0034] In other embodiments of the invention (not shown), other portable power tools comprising a drive means configured to move two blades or two jaws relative to each other between an open position and a closed position may be implemented. For example, the portable power tool may be chosen from a cable cutting tool, a crimping tool, a punching tool or a shear head screw tightening tool. In other embodiments of the invention (not shown), said assembly comprises a portable accessory chosen from a glove or a ring.

[0035] The bracelet 200 is intended to be worn by the user on a separate limb of the user's arm carrying the tool. Thus, the bracelet 200 may be worn on the wrist of the left arm while the pruning shears 100 are held in the right hand, or vice versa.

[0036] The pruning shears 100 and the bracelet 200 will be better understood with reference to Figures 2 and 3 which show exploded views of the pruning shears 100 and the bracelet 200.

[0037] The pruning shears 100 comprise a shell formed of two half-shells, 1 and 2, and having a handle intended to be held in the hand by the user. The shell houses a drive means which comprises a geared motor 3 connected via a bevel gear 17, a bevel gear 16 and a pinion 15 engaged with a blade 14. Thus, the blade 14 is rotatable around an axis 12 and its movement is motorized by a drive means comprising said geared motor 3. The blade 14, rotatable, is also called a cutting blade.

[0038] Preferably, the geared motor 3 is a brushless planetary motor, more commonly referred to by the English term “Brushless”. Such a motor being well known in the prior art, it is not described in detail here.

[0039] The brushless planetary motor is chosen for its ability to withstand intensive opening and closing cycles of up to 2.5 million cycles in 100 days with minimal motor wear. Preferably, the geared motor is controllable to the nearest degree, which allows the blade opening to be adjusted to any position within the opening range. Advantageously, the cutting blade opening is readjusted at regular intervals in order to maintain a constant opening despite successive sharpening operations, which reduce the cutting blade size.

[0040] A body 4 configured to be housed between the two half-shells, 1 and 2, serves as a support for the bevel gear 17, the bevel wheel 16 and the blade gear. A second blade 13 is secured to the body 4. The second blade, fixed in place and secured to the body, is also called a counter-blade.

[0041] A bearing 9 is inserted into the free end of the pinion shaft 15 and a counter plate 8 fixed to the body 4 holds the bearing 9 in place.

[0042] The axle 12 is slid across a through hole drilled in the body 4, then across a threaded hole made in the second blade 13, then across a through hole in the first blade 14 then across a roller thrust bearing 11. Finally, a nut 10 cooperates with a threaded end part of the axle and grips the aforementioned elements between said end cooperating with the nut 10 and the other end of the axle comprising a thrust bearing engaged with the body 4.

[0043] An electronic card 5, also housed in the shell, and comprising a microprocessor and a memory, controls the geared motor 3 and consequently controls the movement of the blade 14. The pruning shears comprise a trigger 6 positioned to be easily activated by the user's grip or finger and electronically connected to the electronic card 5. Provided that the safety conditions specific to the invention, described below, are respected, pressing the trigger controls the passage of the blades 14 and 13 into the closed position. A closed position is defined as a position where the two blades are in contact or at least partly superimposed on each other. An open position is defined as a position which is not a closed position. It is specified that the passage from an open position to a closed position can be carried out by the movement of a single blade, as is the case for the pruning shears 100, or by the movement of both blades.

[0044] The pruning shears 100 comprise a first antenna 18 supported by a second electronic card 7. Advantageously, the second electronic card is fixed to the body 4.

[0045] The electronic parts of the pruning shears 100 are preferably powered by a rechargeable battery of 24 to 48V, the battery being able to be positioned either on the pruning shears, or offset on the belt or on a harness and connected by an electric power cord.

[0046] We now refer to [Fig. 3] which illustrates a bracelet 200 configured to be used in association with the pruning shears 100. The bracelet 200 comprises a strap 20 and a body similar to a watch body housing a second antenna 24. Said body is closed by a cover 23. Preferably, the bracelet 200 comprises an electronic card 21 configured to transmit or receive a signal through the second antenna 24 and / or to process such a signal. Preferably, the bracelet 200 comprises a battery 22 in particular to power the electronic card 21. In embodiments (not shown) the bracelet 200 comprises a display configured to display, for example, information relating to the pruning shears 100 or to a security protocol. In embodiments (not shown) the bracelet 200 comprises a human-machine interface, the function of which will be described later.

[0047] Preferably, the battery 22 is a rechargeable battery.

[0048] The assembly which is the subject of the invention, for example formed of a pruning shears 100 and a bracelet 100, described above, comprises a means for estimating a value representative of the distance DI separating the bracelet and the pruning shears.

[0049] The distance DI between the pruning shears and the assembly is determined as a function of the strength of a signal exchanged between a first antenna positioned on the portable power tool, and a second antenna positioned on the portable accessory. For example, the estimation of the distance DI is carried out by a microprocessor positioned on the pruning shears 100 or on the bracelet 200.

[0050] In embodiments, the first and second antennas are configured to exchange a signal emitted in radio frequencies, in infrared or a signal according to the Bluetooth standard (registered trademark). More preferably, the first antenna and the second antenna are configured to exchange an ultra-wideband (ULB) type signal.

[0051] According to the invention, the blades of the pruning shears 100 are moved or maintained in the open position unless each of the following conditions are satisfied: - the value representative of the distance between the portable accessory and the portable power tool is less than a predetermined threshold, called the activation threshold, - the representative value of the distance separating the portable accessory and the power tool is greater than a predetermined threshold, called the safety threshold.

[0052] The blades of the pruning shears 100 are moved or held in the open position depending on the distance between the pruning shears 100 and the bracelet 200. This means that an opening command is sent to the geared motor if the distance is greater than the activation threshold or less than the safety threshold. This command overrides the closing command of the blades following pressure on the trigger 6, so that it is not possible to move the blades to the closed position when the safety conditions are not met.

[0053] The activation threshold and the safety threshold are configurable. In embodiments, a human-machine interface allows the user of the pruning shears to adjust these distances.

[0054] For example, the activation threshold is a distance value between 1 meter and 2 meters, preferably between 1 meter and 1.5 meters. For example, the safety threshold is a distance value between 10 centimeters and 50 centimeters, preferably between 15 centimeters and 25 centimeters. It is noted that the activation threshold corresponds to a distance strictly greater than the safety threshold.

[0055] In embodiments (not shown), the wearable accessory comprises a verification means configured to estimate whether the wearable accessory is being worn by a user and the blades or jaws are moved or held in the open position unless the verification means estimates that the hand-held or forearm-held accessory is indeed being worn by a user. For example, the verification means comprises an accelerometer positioned on the wearable accessory and the verification means verifies at regular intervals that the data recorded by said accelerometer correspond to active use of the wearable accessory. The verification means is for example a microprocessor positioned on the wearable accessory.

[0056] In embodiments (not shown), the assembly comprises a human-machine interface configured to allow the user to temporarily lift the safety described above, which consists of opening or keeping open the blades or jaws depending on the distance between the power tool and the portable accessory. For example, an interface of the button or touch interface type is provided on the power tool or the portable accessory. Alternatively, this interface can be remote, for example using the interface of a portable communicating terminal of the intelliphone or touch tablet type, said portable communicating terminal being in wireless connection via an antenna with a processor positioned on the power tool.

[0057] Preferably, the data relating to the authorization to temporarily lift the security are recorded in a memory. This data corresponds for example to the date and time of the authorization and to the identity of the person requesting this auto Preferably, the authorization to temporarily lift the safety is limited in time and revoked when the power tool is switched off.

[0058] In embodiments (not shown), the assembly that is the subject of the invention comprises a means for emitting an audible or visual alarm positioned on the portable power tool or positioned on the portable accessory. Said means emits an alarm when the value representative of the distance separating the first and second means for emitting or receiving an electromagnetic signal is less than a predetermined threshold, called the alert threshold.

[0059] For example, the alert threshold corresponds to a distance between 10 and 30 centimeters, for example the alert threshold corresponds to a distance of 20 centimeters. The alarm threshold is preferably between the activation threshold and the safety threshold.

[0060] According to a second particular embodiment illustrated in [Fig.4], the assembly which is the subject of the invention comprises a portable electric tool, in this case a pruning shears similar to the pruning shears 100 already described above and a portable accessory, in this case a bracelet similar to the bracelet 200 already described above and at least one additional portable accessory. The additional accessory being for example a second bracelet 300 intended to be worn by a second user, distinct from a first user handling the pruning shears 100.

[0061] The additional bracelet 300 comprises a third antenna. In addition, the assembly comprises a means for estimating a value representative of the distance D2 separating the bracelet 300 and the pruning shears 100, as a function of the strength of a signal exchanged between the first antenna positioned on the pruning shears 100 and a third antenna positioned on the additional bracelet 300.

[0062] Advantageously, the blades or jaws of the pruning shears 100 are moved or kept in the open position unless the following additional condition is satisfied: the value representative of the distance D2 separating the additional bracelet and the portable power tool is greater than a predetermined threshold.

[0063] For example, this threshold corresponds to a distance between 10 and 50 centimeters. In this case, it is expected that the two users, a first carrying the tool and another user, work side by side, nevertheless the safety of the pruning shears 100 is engaged when the bracelet 300 worn by the second user is too close to the pruning shears 100.

[0064] In another example, this threshold corresponds to a distance greater than one meter, for example between 1 meter and 10 meters. In this case, it is not intended that the two users work next to each other and the safety of the pruning shears engages as soon as the users get too close to each other.

Claims

Claims

1. Assembly characterized in that it comprises: - a portable power tool (100) comprising a drive means configured to move two blades (13 and 14) or two jaws between an open position and a closed position, - a portable accessory (200) intended to be carried by the user on a separate member of the arm of the user carrying the tool, - a means for estimating a value representative of the distance (Dl) separating the portable accessory and the portable power tool, as a function of the strength of a signal exchanged between a first antenna (18) positioned on the portable power tool and a second antenna (24) positioned on the portable accessory and in that the blades or jaws are moved or maintained in the open position unless each of the following conditions are satisfied: - the value representative of the distance (Dl) separating the portable accessory and the portable power tool is less than a predetermined threshold,called activation threshold, - the value representing the distance (Dl) separating the portable accessory and the power tool is greater than a predetermined threshold, called safety threshold.,

2. An assembly according to the preceding claim, which comprises verification means configured to estimate whether the portable accessory (200) is being carried by a user and wherein the blades or jaws are moved or kept in the open position unless the verification means estimates that the portable accessory is indeed being carried by a user.

3. Assembly according to the preceding claim, in which the verification means comprises an accelerometer positioned on the portable accessory (200) and in which the verification means verifies at regular intervals that the data recorded by said accelerometer are representative of active use of the portable accessory.

4. An assembly according to any preceding claim, which comprises a human-machine interface configured to allow the user to temporarily lift the safety so that the drive means can move the at least one blade or jaw to a closed position without prior verification of the distance conditions and in which the authorization data are recorded in a memory.

5. Assembly according to any one of the preceding claims, which comprises means for emitting an audible or visual alarm positioned on the portable power tool (100) or positioned on the portable accessory (200) and in which said means emits an alarm when the value representative of the distance separating the first and second means for emitting or receiving an electromagnetic signal is less than a predetermined threshold, called the alert threshold.

6. An assembly according to any preceding claim, wherein the first antenna and the second antenna are configured to exchange an ultra-wideband (UWB) type signal.

7. An assembly according to any one of the preceding claims, which comprises: - at least one additional portable accessory (300), said additional portable accessory comprising a third antenna, - means for estimating a value representative of the distance (D2) separating the additional portable accessory and the power tool, as a function of the strength of a signal exchanged between the first antenna positioned on the power tool and a third antenna positioned on the portable accessory and in which the blades or jaws are moved or kept in the open position unless the following additional condition is satisfied: - the value representative of the distance (D2) separating the additional portable accessory and the power tool is greater than a predetermined threshold.

8. An assembly according to any one of the preceding claims wherein the power tool is chosen from: pruning shears, a cable cutting tool, a crimping tool, a punching tool or a shear head screw tightening tool.

9. An assembly according to any preceding claim, wherein the wearable accessory is a bracelet, a ring or a glove.

10. An assembly according to any one of the preceding claims in which the power tool is a pruning shears (100) comprising a counter-blade (13) and a cutting blade (14) made movable by a drive means comprising a brushless motor, a planetary reducer, a bevel or spiral bevel gear and an engaged gear with the cutting blade.

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