Electric handheld tool with compact electronics

Abstract

The present invention relates to a portable electric tool comprising a casing housing: an electric motor; an electronic card housed in a portion of said casing, said portion extending along a main axis. According to the invention, said electronic card comprises at least two printed circuits interconnected with each other, said at least two printed circuits being arranged essentially circumferentially around said main axis. Fig. 8

Description

Title of the invention: Electric portable tool with compact electronics 1. Field of the invention

[0001] The field of the invention is that of portable electric tools, corded or battery-powered. 2. Prior art

[0002] Portable power tools, such as screwdrivers, drills or the like, require an external power source for their operation and / or for data transmission.

[0003] This energy supply can be achieved via a battery or via a cable connected to the tool temporarily by a connector (male or female) generally located at one end of the tool.

[0004] These tools also require one or more electronic cards for their operation. These different electronic cards are used to manage: - the power supply of the tool, - management of screwing, drilling or other cycles... - communication with an external box, - a display of reports to the operator,

[0005] These electronic cards can possibly be superimposed.

[0006] Conventionally, a portable electric tool comprises a casing at one end of which there is a rotating terminal member capable of driving in rotation and / or translation an accessory such as a drill bit or a screw socket.

[0007] The terminal member is connected to the output of a transmission whose input is connected to the rotor of a motor.

[0008] In the extension of the motor extend one or more electronic cards, to which the motor is connected, then a connector connected to the electronic cards.

[0009] Generally, the connector part is separate from the electronic card and is connected to it by a cable harness. It is positioned longitudinally after the electronic card part.

[0010] There are also tools in which the connector pins are soldered to a connector circuit board transverse to the tool. This connector circuit board is itself soldered to the main electronic board of the tool.

[0011] Furthermore, there are several solutions for positioning and maintaining electronic cards inside the housing of a tool.

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[0023] The card can be held by screws directly on the housing, possibly with elastomer elements to limit vibrations on the card. Another solution is to hold the electronic card by wedging it between two portions of the casing assembled together to form the casing. Another solution is to place the electronic card in a sheath (holding it for example with screws), then insert the sheath into the tool housing. Whatever solution is implemented, integrating electronic cards into existing tools poses some problems. In particular, the integration of electronic cards into power tools is detrimental to the compactness of the tools. This results from several constraints, including the following. First, the low-voltage electronic cards must maintain minimum insulation distances from the three power cables (high voltage) supplying the three phases of the motor. This distance between the connector and the electronic cards results in an elongation of the tool casing. Secondly, to be comfortably grippable by an operator working daily to carry out tasks, the body of the tools must have a small diameter gripping portion. This small diameter of the tool body, in a region where the connector and the electronic cards are installed, means that it is difficult to install them while respecting the required isolation distances unless the electronic cards are moved away from the connector. In order to comply with these constraints, a sufficient distance in the longitudinal direction is prescribed between the electronic cards and the connector, which means that the body of the tools is relatively long. Furthermore, the systems for holding electronic cards in the body of the tools are quite bulky: - the screws traditionally used to hold the cards take up a lot of space inside the tool; - sliding / pinning card holding systems require a significant thickness of electronic cards to ensure that they are not damaged during assembly; - sheath systems require additional parts that also take up space in the tool body; - card stacks require inter-card connectors and elements to hold them together. All this has the effect of harming the compactness of the different elements and therefore in particular of lengthening the tools. There is therefore a need to improve the integration of electronic cards within

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[0033] power tools. 3. Objectives of the invention The invention aims in particular to provide an effective solution to at least some of these different problems. In particular, according to at least one embodiment, an objective of the invention is to provide a technique for integrating electronic cards into an electrical tool which makes it possible to satisfy the constraints in terms of compliance with the insulation distances between the electronic cards and the connector while offering good comfort of use. In particular, the invention aims, according to at least one embodiment, to provide such a technique which makes it possible to compact, i.e. reduce the size, the integration of electronic cards. Another objective of the invention is, according to at least one embodiment, to provide such a technique which contributes to guaranteeing good reliability, in particular by providing a technique which avoids damage to the cards. Another objective of the invention is, according to at least one embodiment, to provide such a technique which is simple to implement and / or robust and / or reliable and / or economical. 4. Presentation of the invention For this, the invention proposes a portable electric tool comprising a housing housing: - an electric motor; - an electronic card housed in a portion of said housing, said portion extending along a main axis. According to the invention, said electronic card comprises at least two printed circuits interconnected with each other, said at least two printed circuits being arranged essentially circumferentially around said main axis. Thus, according to this aspect of the invention, the printed circuits making up the electronic card of an electric tool are “wound” around the main axis of a portion of the casing. It is thus possible to reduce the length of the electronic card, and therefore that of the tool while: - respecting a minimum isolation distance between the card and the connector, and - providing a small casing diameter. The invention thus makes it possible to provide a tool that respects the required insulation distance between the electronic card and the connector while being compact, which makes it comfortable to use for an operator who works with it to carry out operations.

[0034] According to a possible characteristic, said printed circuits are connected two by two by means of deformable conductive tabs.

[0035] According to a possible characteristic, said portion of said casing houses a support for said electronic card, said support having at least as many support faces as said electronic card comprises printed circuits, said faces extending in planes substantially parallel to said main axis.

[0036] According to a possible characteristic, a tool according to the invention comprises means for securing said electronic card to said support.

[0037] According to a possible characteristic, said securing means comprise holding elements projecting from the surface of said support, said tabs comprising fixing openings each allowing the passage of one of said holding elements.

[0038] According to a possible characteristic, said fixing openings are provided at free ends of said tabs.

[0039] According to a possible characteristic, said holding elements are provided at the junction between two consecutive support faces of said support.

[0040] According to a possible characteristic, a tool according to the invention comprises means for locking said holding elements in said fixing openings.

[0041] According to a possible characteristic, said locking means comprise pins extending laterally to said holding elements along axes parallel to said support surfaces.

[0042] According to a possible characteristic, said locking means comprise slots provided in each of said holding elements along a plane parallel to a support surface from which said holding element projects.

[0043] According to a possible characteristic, at least some of said fixing openings have at least one softening slot at their periphery.

[0044] According to a possible characteristic, a tool according to the invention comprises means for positioning said printed circuits on said support faces.

[0045] According to a possible characteristic, said positioning means comprise pins forming projections on the surface of at least some of said support faces, said pins being capable of cooperating with housings of complementary shape provided in said printed circuits or in said tabs.

[0046] According to a possible characteristic, said support comprises a connector provided with at least one electronic contact capable of being connected to a power source, said support being crossed at least in part substantially along said main axis by at least one cable connected to said motor and / or to said electronic card.

[0047] According to a possible characteristic, said casing comprises a portion housing said motor extending along a main axis, the main axes of the housing portions housing said motor and said electronic card being merged or forming an angle. 5. Description of figures

[0048] Other characteristics and advantages of the invention will appear on reading the following description of particular embodiments, given as a simple illustrative and non-limiting example, and the appended drawings among which:

[0049] [Fig-1] [Fig.l] illustrates a perspective view of an example of a tool according to the invention;

[0050] [Fig.2] [Fig.2] illustrates an example of an electronic card of a tool according to the invention, laid flat;

[0051] [Fig.3] [Fig.3] illustrates a detail of [Fig.2];

[0052] [Fig.4] [Fig.4] illustrates another detail of [Fig.2];

[0053] [Fig.5] [Fig.5] illustrates the electronic card illustrated in [Fig.2] but rolled up around an axis;

[0054] [Fig.6] [Fig.6] illustrates an electronic card support of a tool according to the invention;

[0055] [Fig.7] [Fig.7] illustrates a detail of [Fig.6];

[0056] [Fig.8] [Fig.8] illustrates an electronic card wrapped around the support illustrated in [Fig.6];

[0057] [Fig.9] [Fig.9] illustrates a longitudinal section of a tool according to the prior art;

[0058] [Fig. 10] [Fig. 10] illustrates a partial perspective view of a tool according to the invention in which the support of the electronic card is cut away so as to make the holes passing through it visible;

[0059] [Fig. 11] [Fig. 11] illustrates an electronic card wrapped around the support illustrated in [Fig.6];

[0060] [Fig. 12] [Fig. 12] illustrates a cross-section of a tool according to the prior art.

[0061] 6. Description of particular embodiments 6.1. Structure 6.1.1. Cable power supply

[0062] An example of a portable electric tool according to the invention is presented in relation to Figures 1 to 8 and 10 to 12. It may in particular be a screwdriver, a drill or the like.

[0063] Such a tool comprises a housing 10.

[0064] This casing 10 houses, at one of its ends, a connector 11 which allows the tool to be connected to a cable 12 for electrical power supply and / or data exchange.

[0065] This cable 12 is connected to a controller (not shown) which integrates the intelligence allowing, among other things, the motor to be powered and controlled.

[0066] At the other end of the casing 10 is located a terminal member 13 capable of driving in rotation and / or in translation an accessory such as for example a cutting tool (such as a drill bit, etc.) or a screw socket, etc.

[0067] Between the connector 11 and the terminal member 13, the casing 10 comprises: - a portion of handle 14, - a portion of 15 motorization, and - a transmission portion 16.

[0068] The transmission portion 16 houses a transmission T, generally with gears. This transmission T is connected on the one hand to the terminal member 13 and on the other hand to the rotor R of a motor M housed in the motorization portion 15.

[0069] The handle portion 14 is intended to be held by an operator so as to manipulate the tool.

[0070] This handle portion 14 can extend along a main axis essentially coincident with the axis of the rotor of the motor, as shown in [Fig.l]. Alternatively, it can extend along an axis forming an angle relative to the axis of the rotor. This is then a so-called pistol grip type tool.

[0071] The handle portion 14 houses an electronic card 17. This electronic card 17 may be designed to perform various functions such as, for example, the display of information, the control of torque and / or angle measuring means, the exchange of information with an actuation trigger, the bidirectional exchange of information with the controller, etc.

[0072] In this embodiment, the electronic card 17 comprises four printed circuits 170. However, in variants, the number of printed circuits 170 of the electronic card 17 may be different and will be at least equal to two. It may thus be greater than four, and thus for example be equal to 2, 3, 4, 5, 6...

[0073] The printed circuits 170 are arranged essentially circumferentially around the main axis of the handle portion 14. In other words, they are “wound” around this axis.

[0074] For this, the printed circuits 170 are connected two by two by means of deformable conductive tabs 18.

[0075] More precisely, the electronic card 17 comprises two tabs 18 which extend essentially parallel to each other and to which the printed circuits 170 are secured, by gluing or otherwise, preferably at regular intervals.

[0076] The portions 180 of tabs 18 located at the junction between two consecutive printed circuits 17 can be folded to wind the printed circuits 17 around an axis, and thus form hinges of some sort.

[0077] The portion of casing 10 which houses the electronic card 17, in this case the portion of handle 14, also houses a support 19 for the electronic card 17.

[0078] This support 19 has at least as many support faces 190 as the electronic card 17 comprises printed circuits 170. In the present embodiment, the support 19 therefore comprises four support faces 190. These support faces 190 extend in planes substantially parallel to the main axis of the casing portion 10 housing the electronic card 17, in this case the handle portion 14.

[0079] The tool comprises means for securing the electronic card 17 to the support 19.

[0080] These securing means, reversible or not, could for example be: - an elastic ring of the toric joint type surrounding the printed circuits and keeping them pressed against the support faces; - glue for sticking each printed circuit 170 to the corresponding support face 190; - screws; - rivets; - clips...

[0081] In the illustrated embodiment, these securing means comprise holding elements 191 projecting from the surface of the support 19.

[0082] In this embodiment, these holding elements 191 are two in number and are positioned at the junction between two consecutive support faces 190. They are spaced apart by a center distance substantially identical to the center distance of the tabs 18.

[0083] The tabs 18 comprise, at each of their free ends, not connected to a printed circuit 170, a fixing opening 181 allowing the passage of one of these holding elements 191.

[0084] Each holding element 191 has a first end extending to the surface of a first support face 190 and a second end extending to the surface of the second support face 190 following the first.

[0085] The first of these ends comprises a locking slot 192 arranged along a plane essentially parallel to the plane of the first support face 190.

[0086] The second of these ends comprises pins 193 extending laterally to the holding elements 191 along axes parallel to the support faces 190.

[0087] The slots 192 and the pins 193 constitute means for locking the holding elements 191 in the fixing openings 181, as will become more clear later in the description.

[0088] At least two of the openings 181 may have at their periphery at least one softening slot 182. These softening slots 182 are preferably provided on two end tabs 180 located on the same side of the electronic card.

[0089] In variants: - the slots 192 may be replaced by pins 193, in which case there will be no slots 192; - the nipples 193 may be replaced by slots 192, in which case there will be no nipples 193; - the position of the nipples 193 and the slots 192 may be reversed with respect to that shown in the drawings.

[0090] In this embodiment, the tool comprises means for positioning the printed circuits 170 on the support faces 190.

[0091] In this embodiment, these positioning means comprise pins 194 forming projections on the surface of at least some of the support faces 190. These pins 194 are capable of cooperating with housings 171 of complementary shape provided in the printed circuits 17 or in the tabs 18.

[0092] Preferably, at least one housing 171 will be provided in each printed circuit 17, and more preferably at least two. As many pins 194 will be provided as there are housings 171.

[0093] The support 19 comprises the connector 11, or at least its terminal block-forming part 110, provided with at least one electronic (or electrical) contact.

[0094] In the present embodiment, the terminal block 110 comprises three electrical contacts 111 capable of being connected to an electricity supply source to supply the phases of the motor M. These contacts 111 are connected to the phases of the motor M by wires protected in a sheath 20 which passes through a hole 21 passing longitudinally through the support 19.

[0095] The terminal block 110 also comprises electrical contacts 112, of any number, some of which are capable of being connected to a power supply source and others to the controller. These contacts 112 are connected to the electronic card 17 by wires 22 which pass through a hole 23 provided for this purpose in the support 19 and preferably opening at the periphery thereof through an orifice 24. These contacts 112 allow the electronic card 17 to be supplied with power and to exchange information with the controller. 6.1.2. Battery power supply

[0096] When the connector 11 is not used to connect the tool to a cable 12 but to at least one battery, all the wires connected to the contacts 111, 112 are connected to the electronic card 17 and the electronic card 17 is connected to the motor M to enable, in addition to its other functions, to provide power and control. 6.2. Assembly

[0097] The assembly of the electronic card 17 to the casing 10 is obtained in the manner next.

[0098] Before being assembled to the tool, the electronic card 17 extends in a plane as shown in [Fig.2].

[0099] To assemble the electronic card 17 to the tool, the two holding elements 191 are engaged in two of the openings 181 of its tabs 18, located on the same side of the electronic card 17, taking care to slide the edge of the openings 181 into the slots 192. Thus, these two ends of the tabs 18 are held integral with the holding elements 191.

[0100] The first printed circuit 170, connected to the ends of the tabs 18 secured to the holding elements 191, is then applied against the corresponding support face 190, taking care to introduce the pins 194 of this support face 190 into the housings 171 of this printed circuit 170.

[0101] The portions 180 of tabs 18 located between the printed circuit 170 which has just been pressed against the support face 190, are folded so as to apply the following printed circuit 17 against the corresponding support surface 190, taking care to introduce the pins 194 of this support face 190 into the housings 171 of this printed circuit 170.

[0102] This type of operation is repeated twice to press the other two printed circuits 170 against the two following support faces 190.

[0103] The two holding elements 191 are then introduced into the openings 181 of the two free ends of the tabs 18. The softening slots 182 make it easier for the pins 193 to pass through the openings 181.

[0104] The electronic card 17 is then secured and locked onto the support 19 of the tool. 6.3. Advantages

[0105] The technique according to the invention provides numerous advantages, including in particular: - the provision of a compact and comfortable tool to use since the implementation of an electronic card wrapped around the tool makes it possible to reduce the length of the card, and to reduce the length and diameter of the tool; - to improve the insulation of the motor power cables from the electronic card by causing them to pass inside the electronic card support, which avoids having to, as is the case with the prior art illustrated in [Fig.9], move the electronic card away from the connector to satisfy the insulation level; this also contributes to reducing the length of the tool.

Claims

Claims

1. Portable electric tool comprising a casing housing: - an electric motor; - an electronic card housed in a portion of said casing, said portion extending along a main axis, characterized in that said electronic card comprises at least two printed circuits interconnected with each other, said at least two printed circuits being arranged essentially circumferentially around said main axis.

2. Tool according to claim 1 wherein said printed circuits are connected two by two by means of deformable conductive tabs.

3. Tool according to claim 1 or 2 characterized in that said portion of said casing houses a support for said electronic card, said support having at least as many support faces as said electronic card comprises printed circuits, said faces extending in planes substantially parallel to said main axis.

4. Tool according to claim 3 comprising means for securing said electronic card to said support.

5. Tool according to claims 2 and 4 wherein said securing means comprise holding elements projecting from the surface of said support, said tabs comprising fixing openings each allowing the passage of one of said holding elements.

6. A tool according to claim 5 wherein said fixing openings are provided at free ends of said tabs.

7. Tool according to claim 5 or 6 wherein said holding elements are provided at the junction between two consecutive support faces of said support.

8. Tool according to claim 5 or 6 comprising means for locking said holding elements in said fixing openings.

9. A tool according to claim 8 wherein said locking means comprise pins extending laterally to said holding members along axes parallel to said support surfaces.

10. A tool according to claim 8 or 9 wherein said ver- rusting comprises slots formed in each of said holding elements along a plane parallel to a support surface from which said holding element projects.

11. Tool according to claim 9 or 10 in which at least some of said fixing openings have at least one softening slot at their periphery.

12. Tool according to any one of claims 3 to 11 comprising means for positioning said printed circuits on said support faces.

13. Tool according to claim 12 wherein said positioning means comprise pins forming projections on the surface of at least some of said support faces, said pins being capable of cooperating with complementary shaped housings provided in said printed circuits or in said tabs.

14. Tool according to any one of claims 3 to 13 in which said support comprises a connector provided with at least one electronic contact capable of being connected to a power source, said support being crossed at least in part substantially along said main axis by at least one cable connected to said motor and / or to said electronic card.

15. Tool according to any one of claims 1 to 14 wherein said casing comprises a portion housing said motor extending along a main axis, the main axes of the casing portions housing said motor and said electronic card being merged or forming an angle.

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