drilling device comprising a sliding gear driven by a cam system

Abstract

The invention relates to a drilling device comprising a sliding gear movable between an engaged position and a stationary position, said device comprising first means for moving said fourth gear from said stationary position to said engaged position, said first means of movement comprising a cam system. Fig. 2

Description

Title of the invention: Drilling device comprising a sliding gear actuated by a cam system 1. Scope of the invention

[0001] The field of the invention is that of drilling devices. 2. Prior art

[0002] Drilling devices, also called drills, are commonly used in various industrial sectors, such as aeronautics, to perform various tasks. In this sector, drills with automatic feed are commonly used; that is, drills whose drilling spindle (or output spindle), which carries a cutting tool, can be driven simultaneously in translation and rotation about its longitudinal axis.

[0003] Patent documents FR-A1-2 881 366 and FR-A1-2 918 592 describe such drills, for example.

[0004] With reference to [Fig. 1], a drill of this type classically comprises:

[0005] - a grooved and threaded output pin 10;

[0006] - a pneumatic motor (not shown), connected to a supply valve compressed air, or electric, equipped in both cars with an R rotor;

[0007] - a transmission T capable of transforming a rotational movement of the rotor R into a rotational and / or translational movement of the output spindle 10 along the same axis, i.e. its longitudinal axis.

[0008] This transmission T comprises:

[0009] - a first pinion 11 coaxial with the spindle 10 and provided with internal splines cooperating with the external grooves of spindle 10;

[0010] - a second pinion 12 coaxial with the spindle 10 and provided with an internal thread cooperating with the thread of spindle 10;

[0011] - a third pinion 13 with an axis parallel to the spindle 10, meshing with the first pinion 11 following a first transmission ratio and driven in rotation by the drill motor via a pair of bevel gears 15 and / or one or more epicyclic gear trains and / or spur gears (not shown);

[0012] - a fourth pinion 14 with an axis parallel to the spindle 10, meshing with the second pinion 12 following a second transmission ratio different from the first ratio.

[0013] The fourth pinion 14 includes first ogive-shaped dog clutches 140 capable of cooperating with complementaryly shaped clutch housings 130 provided on the third pinion 13 such that when the dog clutches 140 are housed in the clutch housings 130, the fourth pinion 14 and The third pinion 13 are rotationally linked. As will be described in more detail later, the ogive shape of the first dogs makes them suitable for disengaging the rotational link when the fourth and third pinions have started to move away from each other.

[0014] More specifically, the separation of the third and fourth pinions is used to trigger the supply of a cylinder allowing the fourth pinion to complete its movement towards its immobilized position.

[0015] From the stage where the third and fourth pinions are still glued together, the shape of the ogives allows, under the increase of a torque between the third and fourth pinions, to exert a force between the third and fourth pinions tending to separate them.

[0016] This torque appears when the spindle reaches the end of its extension and the motor continues to exert a driving torque on the third gear. At this point, since the spindle can no longer advance, the first and second gears are locked in rotation relative to each other. Because the reduction ratios between the first and third gears and the second and fourth gears are different, the third and fourth gears tend to rotate at different speeds. Thus, the torque between these third and fourth gears is generated.

[0017] The fourth pinion 14 also includes second dog clutches 141 with a shape complementary to the locking dog clutches 17 fixed relative to the drill housing C. These dog clutches do not have a shape capable of disengaging the fourth pinion from the housing.

[0018] The fourth pinion 14 is fixed in translation to the rod 160 of the piston 161 and free to rotate relative to it. This rod 160 is movable in translation along the axis of rotation of the fourth pinion in a chamber 162 of a monostable cylinder 16 so as to be able to:

[0019] - an engaged position in which the first dogs 140 are housed in the clutch housings 130 and the second dogs 141 do not cooperate with the locking dogs 17, so that the fourth pinion 14 is rotationally linked with the third pinion 13 and is rotationally mobile relative to the housing C, and

[0020] - a stationary position in which the first 140 dog clutches do not cooperate with the clutch housings 130 and the second dogs 141 cooperate with the locking dogs 17 so that the fourth pinion 14 is fixed in rotation relative to the housing C and mobile in rotation relative to the third pinion 13.

[0021] To move the fourth pinion 14 from its engaged position to its immobilized position, the side of the chamber 162 of the cylinder 16, oriented towards the fourth pinion 14, is supplied with compressed air. The fourth pinion 14 then moves away from the third pinion 13 against the effect of the spring 163.

[0022] To move the fourth pinion 14 from its immobilized position to its engaged position, the chamber 162 of the cylinder 16 is opened to the air by means of a distributor (not shown) so as to bring the fourth pinion 14 closer to the third pinion 13 under the effect of the spring 163.

[0023] The spindle 10 is provided with a deployment end stop 18 capable of bearing against a fixed deployment end stop in translation (here the first pinion 11) relative to the housing, and a retraction end stop 19 capable of bearing against a retraction end stop (here the second pinion) fixed relative to the housing.

[0024] When starting the drill to perform a drilling operation with or without countersinking, the end stop for retraction 19 is in contact with the end stop for retraction (i.e. the second pinion 12) so that the spindle 10 is completely retracted.

[0025] The fourth pinion 14 is in the engaged position in which it is rotationally linked with the third pinion 13.

[0026] The motor is supplied in the direction of operation (i.e., drilling) such that the third pinion 13 is driven in rotation. The fourth pinion 14, which is rotationally linked with the third pinion 13, rotates at the same speed.

[0027] The first pinion 11 is driven in rotation by the third pinion 13 so that the spindle 10 is driven in rotation along its longitudinal axis.

[0028] The second pinion 12 is driven in rotation by the fourth pinion 14.

[0029] The reduction ratio between the first 11 and the third pinion 12 is different of the reduction ratio between the second pinion 12 and the fourth pinion 14. Thus, given the helical connection between the second pinion 12 and the spindle 10, the spindle 10 is driven in translation along its axis and extends out of the housing until the end-of-deployment stop 18 is against the end-of-deployment stop (i.e. of the first pinion 11).

[0030] When the deployment end stop 18 is against the deployment end stop, the deployment of the spindle 10 is stopped, so that the second pinion 12 is forced to rotate at the same speed as that of the spindle 10 and that of the first pinion 11. The third 13 and the fourth 14 pinions therefore tend to rotate at different speeds due to the difference in reduction ratios mentioned above. Thus, given the ogive shape of the first dog clutches 140 of the fourth pinion 14, these dog clutches 140 tend to disengage from the clutch housings 130 of the third pinion 13, so that the fourth pinion 14 moves away from the third pinion 13 towards its stationary position.

[0031] This relative distance of the fourth pinion 14 from the third pinion 13 actuates the distributor (not shown) which supplies the side oriented towards the fourth pinion 14 of the chamber 162 of the cylinder 16. As a result, the cylinder 16 drives, against the effect of the spring 163, the fourth pinion 14 into its immobilized position in which it is fixed in rotation relative to the housing without being linked in rotation to the third pinion 13.

[0032] Given that the fourth pinion 14 is prevented from rotating, the second pinion 12 is also prevented from rotating relative to the housing. Thus, the spindle 10, which continues to be driven in rotation by the third 13 and the first 11 pinions, moves in translation along its axis in the direction of a retraction inside the housing.

[0033] The pitch of the threaded area of ​​the spindle 10 and the difference between the reduction ratios mentioned above result in the following: when the fourth pinion 14 is locked, the spindle 10 retracts at an appropriate speed, and when the fourth pinion 14 is engaged with the third pinion 13, the feed per revolution of the spindle 10 conforms to an appropriate value. This transmission principle is known in the prior art and will not be described in further detail.

[0034] The retraction of the spindle 10 is done until the end retraction stop 19 is in contact with the end retraction stop.

[0035] When the end stop of retraction 19 is in contact with the end stop of retraction, it acts on a distributor allowing the chamber of the cylinder 16 to be opened to the air and the motor supply valve to be closed.

[0036] The chamber 162 is no longer pressurized so that the piston 161 moves under the effect of the spring 163. The piston 161 thus drives the fourth pinion 14 into its engaged position in which the first dogs 140 are housed in the clutch housings 130 so that the fourth pinion 14 is again linked in rotation with the third pinion 13.

[0037] The drilling device is thus ready to perform a new drilling operation.

[0038] These drilling devices are very efficient. However, whether the drill motor is pneumatic or electric, a pneumatic actuator is used to move the fourth pinion into its immobilized position after the spindle has been fully extended.

[0039] This therefore systematically implies the need to supply the drill with compressed air, which limits the use of such a drill in places with a compressed air supply infrastructure.

[0040] When the drill has a pneumatic motor, it is logical that it should be used in locations equipped with a compressed air supply infrastructure. The The fact that the actuator used to move the fourth pinion is pneumatic does not in itself pose a difficulty.

[0041] On the other hand, when the drill motor is electric, the fact that the actuator used to move the fourth pinion is pneumatic implies having both a compressed air supply infrastructure and an electricity supply infrastructure.

[0042] These prior art automatic feed drills can thus be improved, in particular so as not to require a pneumatic actuator to ensure the movement of the fourth pinion. 3. Objectives of the invention

[0043] The invention aims in particular to provide an effective solution to at least some of these different problems.

[0044] In particular, according to at least one embodiment, an objective of the invention is to optimize automatic feed drills.

[0045] In particular, the invention aims, according to at least one embodiment, to provide such a drill in which the movement of the fourth pinion does not require a supply of compressed air.

[0046] Another objective of the invention is, according to at least one embodiment, to provide such a drill which can operate entirely electrically without requiring pneumatic power.

[0047] Another objective of the invention is to provide, in at least one embodiment, such a technique which is simple and / or robust and / or economical. 4. Presentation of the invention

[0048] To this end, the invention proposes a drilling device comprising a housing containing:

[0049] - a motor comprising a rotor capable of rotating in a direction of work;

[0050] - a transmission;

[0051] - a drilling spindle capable of being driven in rotation or in rotation and in translation along a longitudinal axis of said spindle via said motor and said transmission;

[0052] said transmission comprising:

[0053] - a first pinion linked in rotation with said spindle and mounted movable in translation along said spindle along said longitudinal axis of said spindle;

[0054] - a second pinion linked to said spindle by a helical connection along said axis longitudinal of said spindle;

[0055] - a third pinion, meshing with said first pinion, guided in rotation by report to said casing and capable of being driven into rotation by said engine;

[0056] - a fourth pinion, guided in rotation and translation relative to said housing meshing with said second pinion, said fourth pinion being movable between:

[0057] - an engaged position in which it is rotationally linked with said third pinion by first means of connection, the rotational drive of said third pinion by said motor in said working direction inducing a deployment of said spindle over a predetermined deployment stroke;

[0058] - an immobilized position in which it is rotationally linked to said housing by second means of connection and it is free in rotation vis-à-vis said third pinion, a rotation of said third pinion by said motor in said working direction inducing a retraction of said spindle following a predetermined retraction stroke.

[0059] According to the invention, such a device comprises first means for moving said fourth pinion from said stationary position to said engaged position, said first means comprising: - means for reversing the direction of rotation of said rotor capable of rotating said rotor in the opposite direction to said working direction; - a sliding shaft carrying said fourth pinion and linked in translation to said fourth pinion along its axis of rotation; - a one-way clutch configured for: - not to link the said third pinion and the said sliding shaft in rotation when the said rotor rotates in the said direction of operation, and - to link in rotation said third pinion and said sliding shaft when said rotor rotates in said opposite direction to said working direction; - a cam shaped to induce, during a rotation of said rotor in said opposite direction to said working direction, a displacement of said sliding shaft and of said fourth pinion from said immobilized position to said engaged position,

[0060] said cam being annular and coaxial with said sliding shaft, said cam having a ramp whose development is parallel to the axis of rotation of said sliding shaft, said ramp being in contact with a lug fixed in rotation to said sliding shaft along the axis of rotation of said sliding shaft and at least partially fixed in translation to said sliding shaft along the axis of rotation of said sliding shaft.

[0061] In this way, a rotation of said rotor in the opposite direction of said working direction induces a displacement of said lug on said cam and a displacement of said sliding shaft and of said fourth pinion from said immobilized position to said engaged position.

[0062] Thus, according to this aspect, the invention consists of implementing a cam system to move the fourth pinion to its engaged position. According to the invention, this The movement of the fourth pinion is thus achieved without the use of pneumatic means.

[0063] The invention can thus make it possible to produce a drilling device which does not need to be connected to a pneumatic power source to operate, and which can operate entirely with an electrical power supply.

[0064] According to one possible feature, said first means of movement comprise a coaxial ring said sliding shaft and movable in translation along the axis of rotation of said sliding shaft relative to said sliding shaft, said lug being linked in translation and in rotation to said ring, linked in rotation to said sliding shaft, and movable in translation relative to said sliding shaft along said axis of rotation, an elastic element being disposed between said ring and a shoulder carried by said sliding shaft.

[0065] In this way, a rotation of said rotor in the opposite direction of said working direction tends to move said ring towards said fourth pinion and to compress said elastic element between said ring and said shoulder if the first dogs of said fourth do not extend in the continuation of the second dogs of said third pinion.

[0066] According to one possible feature, a device according to the invention comprises means for retaining said fourth pinion in its engaged position and in its immobilized position, and second means for moving said fourth pinion from its engaged position to its immobilized position, and vice versa, said retaining means and said second means for moving comprising a bistable elastic element capable of taking two stable states, namely:

[0067] - a clutch state in which it maintains said fourth pinion in its engaged position, and

[0068] - a state of immobilization in which it maintains said fourth pinion in its immobilized position.

[0069] According to one possible feature, a device according to the invention comprises a sliding shaft carrying said fourth pinion and linked in translation to said fourth pinion along its axis of rotation, said bistable elastic element comprising at least one elongated element having two ends, one of said ends being articulated at at least a first articulation point on said housing and the other of said ends being articulated at at least a second articulation point on said sliding shaft, said at least one elongated element being compressible in a direction collinear with a line passing through said two ends and having a predetermined stiffness, said sliding shaft being movable relative to said housing between positions corresponding to said engaged and immobilized positions of said fourth pinion, said second articulation point of said sliding shaft occupying, in said states of engagement and immobilization, of positions substantially symmetrical with respect to a median plane perpendicular to said sliding shaft and passing through said first articulation point of said housing, the distance between said ends of said at least one long element taken in a relaxed state being greater than the distance between said first and second articulation points when said second articulation point of said sliding shaft is in said median plane.

[0070] According to one possible characteristic, said at least one elongated element belongs to the group comprising:

[0071] - a metal blade whose compressibility results from its buckling;

[0072] - a component incorporating a spring whose compressibility results from compression said jurisdiction.

[0073] According to one possible feature, said bistable elastic element comprises a bistable elastic washer.

[0074] According to one possible feature, a device according to the invention comprises second means for moving said fourth pinion from said engaged position to said stationary position, said second means comprising:

[0075] - a first end-of-deployment stop integral with said spindle and intended to come in support against a second end-of-deployment stop linked to said housing, said first and second end-of-deployment stops delimiting the end of said deployment stroke of said spindle,

[0076] - said first means of connection which include pins fixed to said fourth pinion and extending along its axis of rotation, said pins being able to cooperate with clutch housings provided for this purpose in said third pinion in said engaged position to link in rotation said third and fourth pinions, said pins and clutch housings being shaped to induce a displacement of said fourth pinion in the direction of said immobilized position when said first end-of-deployment stop is in contact with said second end-of-deployment stop and said rotor rotates in said working direction, said displacement taking place over a stroke inducing said second articulation point of said sliding shaft to pass said median plane and the passage of said bistable elastic element into said immobilized state.

[0077] According to one possible feature, a device according to the invention comprises second means for moving said fourth pinion from said engaged position to said immobilized position, said second means comprising an actuator capable of transmitting said fourth pinion a displacement force capable of bringing said second articulation point to said sliding shaft exceeding said median plane and to move said bistable elastic element from said clutch state to said immobilization state, said actuator being able to take at least:

[0078] - a neutral state in which it does not transmit said displacement effort to said fourth pinion, said neutral state being maintained when said spindle is moved over said predetermined extension stroke and over said predetermined retraction stroke, and

[0079] - a displacement state in which it transmits to said fourth pinion said force of displacement, said state of displacement being taken, at the end of a deployment of said spindle over the whole of said predetermined deployment stroke, under the effect of a rotation of said rotor in said working direction.

[0080] According to one possible feature, said actuator comprises a movable lever capable of taking:

[0081] - said neutral state in which said pin does not transmit any force to said lever and said lever does not transmit said displacement force to said fourth pinion so that said fourth pinion is held in said engaged position by said bistable elastic element in engagement state, said neutral state being maintained when said spindle is moved on said predetermined deployment stroke and on said predetermined retraction stroke;

[0082] - said state of displacement, taken at the end of a deployment of said spindle on the entirety of said predetermined deployment stroke, under the effect of a rotation of said rotor in said working direction, in which said lever transmits said displacement force to said fourth pinion so as to bring said second articulation point of said sliding shaft beyond said median plane and to cause said bistable elastic element to pass from said engaged state to said immobilized state,

[0083] said device comprising a first deployment end stop integral with said spindle and intended to bear against a second deployment end stop linked to said housing, said first and second deployment end stops delimiting the end of said deployment stroke of said spindle, said device comprising a second elastic return element against the effect of which said first pinion is mounted mobile in translation along said spindle when, a rotation of said spindle in said working direction, when said first deployment end stop is in contact with said second deployment end stop, inducing a translational drive, along said spindle, of said first pinion by said second pinion, said first pinion acting on said lever to place it in its moving state.

[0084] According to one possible feature, a device according to the invention comprises:

[0085] - means for maintaining said fourth pinion in its engaged position, said means of maintaining said fourth pinion in its engaged position comprising a magnetic attraction element exerting on said fourth pinion, when it is in said engaged position, a force maintaining it in said engaged position, and

[0086] - of the second means of moving said fourth pinion from its position engaged in its immobilized position, said second means of movement comprising a first elastic return element exerting on said fourth pinion a force tending to move it from its engaged position to its immobilized position, and when it is in said immobilized position, a force maintaining it in said immobilized position.

[0087] According to one possible characteristic, said magnetic attraction element is a permanent magnet.

[0088] According to one possible characteristic, said permanent magnet is an electromagnet.

[0089] According to one possible feature, a device according to the invention comprises means of deactivating the holding effect of said holding means of said fourth pinion in said engaged position.

[0090] According to one possible feature, said deactivation means include means for supplying electricity to said electromagnet so as to cancel the magnetic attraction it generates.

[0091] According to one possible feature, said means for deactivating the holding effect of said holding means of said fourth pinion in said engaged position comprise an actuator capable of transmitting said fourth pinion a repulsive force greater than the magnetic attraction force transmitted to said fourth pinion by said magnetic attraction element, said actuator being able to take at least:

[0092] - a neutral state in which it does not transmit said repulsive effort to said fourth pinion, said neutral state being maintained when said spindle is moved over said predetermined extension stroke and over said predetermined retraction stroke, and

[0093] - a state of repulsion in which it transmits to said fourth pinion said effort of repulsion, said state of repulsion being taken, at the end of a retraction of said spindle over the whole of said predetermined retraction stroke under the effect of a rotation of said rotor in said working direction.

[0094] According to one possible feature, said actuator comprises a movable lever capable of taking:

[0095] - said neutral state in which said pin does not transmit any force to said lever and said lever does not transmit said repulsive force to said fourth pinion, so that said fourth pinion is held in said engaged position by said magnetic attraction element, said neutral state being maintained when said spindle is moved on said predetermined deployment stroke and on said predetermined retraction stroke;

[0096] - said state of repulsion, taken at the end of a deployment of said pin on the entirety of said predetermined deployment stroke, under the effect of a rotation of said rotor in said working direction, in which said lever transmits said repulsive force to said fourth pinion so as to counteract the magnetic attraction force transmitted by said magnetic attraction element to said fourth pinion,

[0097] said device comprising a first deployment end stop integral with said spindle and intended to bear against a second deployment end stop linked to said housing, said first and second deployment end stops delimiting the end of said deployment stroke of said spindle, said device comprising a second elastic return element against the effect of which said first pinion is mounted movable in translation along said spindle, a rotation of said spindle, in said working direction, when said first deployment end stop is in contact with said second deployment end stop, inducing a translational drive, along said spindle, of said first pinion by said second pinion, said first pinion acting on said lever to place it in its repulsion state.

[0098] According to one possible feature, said ramp of said annular cam includes a projecting end in the direction of the engaged position of said fourth pinion and a recessed end receiving said pin when said fourth pinion is in the immobilized position, said device including means for immobilizing the rotation of said sliding shaft when said fourth pinion is in the engaged position such that the trajectory of said pin during the passage of the fourth pinion from its engaged position to its immobilized position is parallel to the axis of said sliding shaft. 5. Description of the figures

[0099] Other features and advantages of the invention will become apparent from the following description of particular embodiments, given by way of simple illustrative and non-limiting example, and the accompanying drawings, among which:

[0100] [Fig-1] [Fig. 1] illustrates a partial longitudinal cross-sectional view of a drill according to the prior art;

[0101] [Fig.2] Fig.2 (a) illustrates a partial longitudinal view of a drill according a first embodiment of the invention employing a magnet whose fourth pinion is in the engaged position, [Fig.2] (b) illustrates a side detail view of the cam system of this drill, and [Fig.2] (c) illustrates a cross-sectional view along axis AA of [Fig.2] (a);

[0102] [Fig.3] Fig.3 (a) illustrates a partial longitudinal view of a drill according a first embodiment of the invention employing a magnet whose fourth pinion is in immobilized position, [Fig.3] (b) illustrates a side detail view of the cam system of this drill, and [Fig.3] (c) illustrates a cross-sectional view along axis BB of [Fig.3] (a);

[0103] [Fig.4] [Fig.4] illustrates a partial perspective view of the cam system of the drill of figures 2 and 3;

[0104] [Fig.5] [Fig.6] Figures 5 and 6 illustrate partial longitudinal section views of a drill according to a first embodiment, not covered by the set of claims, implementing a fork;

[0105] [Fig.7] [Fig.7] illustrates a partial longitudinal view of a drill according to a second embodiment of the invention implementing a bistable elastic element whose fourth pinion is in the engaged position;

[0106] [Fig.8] [Fig.8] illustrates a partial longitudinal view of a drill according to a second embodiment of the invention implementing a bistable elastic element whose fourth pinion is in an intermediate position between its engaged and immobilized positions;

[0107] [Fig.9] [Fig.9] illustrates a partial longitudinal view of a drill according to a second embodiment of the invention implementing a bistable elastic element whose fourth pinion is in a fixed position;

[0108] [Fig. 10] [Fig. 10] illustrates a perspective view of a bistable elastic washer of a drill according to the second embodiment of the invention.

[0109] 6. Description of particular embodiments

[0110] 6.1. First embodiment: magnet device 6.1.1. Architecture

[0111] An example of an embodiment of a drill according to the invention comprising a magnet is presented in relation to figures 2 to 6. Actuation button

[0112] The drill conventionally includes a start button (not shown).

[0113] Such a start button does not require sustained pressure from the operator as required by a trigger.

[0114] The operator presses the start button once to initiate a drilling operation. The drilling operation then proceeds until the drill stops automatically. However, an emergency stop button is provided for early shutdown if necessary. Ordering methods

[0115] The drill also conventionally includes control means 300, such as a controller internal or external to the drill housing, comprising electronic and logic components, which allow the operation of the drill. Such a controller is in itself conventional except that it is configured and programmed to allow the control of a drill according to the invention.

[0116] Motorized spindle drive transmission

[0117] Such a drill typically comprises a housing 20. It preferably also comprises means for attaching the housing 20 to drilling grids. Such drilling grids are known per se and are therefore not described in further detail here.

[0118] The housing 20 contains a spindle 10 which can be deployed outside the housing 20. This spindle 10 is adapted to carry, at one of its ends, a cutting tool such as a drill bit (not shown). This drill bit is coaxial with the spindle 10 and rotationally linked to it.

[0119] The pin 10 includes longitudinal grooves 101 and is threaded 102 along its entire length.

[0120] Pin 10 is equipped with:

[0121] - of a first end-of-deployment stop 18 capable of providing support against a second fixed end-of-deployment stop in translation relative to the housing 20 along the axis of the spindle 10, in this case the second end-of-deployment stop is constituted here by a ball bearing 37 which will be described in more detail later, and

[0122] - of a first end stop for retraction 19 capable of bearing on a second fixed end stop for retraction in translation relative to the housing 20 along the axis of the spindle, in this case the second end stop for retraction is constituted here by the end of a second pinion 12 which will be described in more detail later.

[0123] The first 18 and second 37 deployment end stops define a predetermined deployment stroke of the pin 10.

[0124] The first 19 and second 12 retraction end stops define a predetermined retraction stroke of the spindle 10.

[0125] The drill bit is intended to be secured to the spindle 10 on the side of the first end stop of retraction 19.

[0126] The drill includes an electric motor (not shown) equipped with a rotor R.

[0127] The drill includes a transmission T. This transmission T is interposed between the motor rotor R and the spindle 10. It is capable of transforming a rotational movement of the rotor in the working direction (i.e. drilling direction) into a rotational movement or a combined rotational and translational movement of the output spindle 10 along the same axis, i.e. its longitudinal axis X.

[0128] This transmission T comprises:

[0129] - a first pinion 11 coaxial with the spindle 10 and provided with internal splines cooperating with the external longitudinal grooves of the spindle 10 (the first pinion 11 and the spindle 10 are thus linked by a linear connection along the longitudinal axis of the spindle 10);

[0130] - the second pinion 12 coaxial with the spindle 10 and provided with an internal thread cooperating with the thread 102 of the spindle 10 (the second pinion 12 and the spindle 10 are thus linked by a helical connection along the longitudinal axis of the spindle 10);

[0131] - a third pinion 13 with an axis parallel to the spindle 10, guided in rotation by relative to the casing 20, engaging with the first pinion 11 according to a first transmission ratio and driven in rotation by the drill motor directly or via any type of gear(s) in particular here a straight pinion 15;

[0132] - a fourth pinion 14 with an axis parallel to the spindle 10, guided in rotation and in translation relative to the casing 20, engaging with the second pinion 12 according to a second transmission ratio different from the first ratio. Optional vibrator

[0133] Optionally, the drill includes a vibrator. The vibrator is a mechanical device which, when used on a drilling device, adds an alternating component to the spindle's feed motion. This component allows the cutting edges of the drill bit attached to the spindle to emerge from the material several times per revolution, thus fragmenting the chips. This makes it easier to extract the chips from the hole during drilling and reduces the risk of clogging or damage to the hole wall.

[0134] The vibrator is in the form of a roller thrust bearing, one of whose tracks has corrugations. Thus, when the tracks rotate relative to each other, the thickness of the vibrator varies between minimum and maximum values, several times per revolution.

[0135] This is achieved in the following manner.

[0136] The assembly consisting of the spindle 10, the first pinion 11 and the second pinion 12, is guided in rotation relative to the housing 20 by means of a bearing 30 and a bearing 31. A ball thrust bearing 32 essentially prevents friction between the first 11 and second 12 pinions.

[0137] The vibrator comprises a first track 33, without surface undulations, bearing against the bearing 30. It also comprises rollers 34 that bear against the first track 33. The vibrator further comprises a second track 35 having surface undulations. This track 35 bears against the first pinion 11 and the rollers 34.

[0138] It is possible not to use a vibrating device. Otherwise, it is provided, where appropriate, to be deactivated during the operation of a countersink.

[0139] The drill includes a ball bearing 37, which acts as a second end-of-extension stop. This ball bearing 37 is mounted on a ring 39 fixed relative to to the housing 20. This ring 39 includes, oriented towards the bearing 30, a surface 390 against which one end of a compression spring 40, called the countersink finishing spring, may bear. This spring 40 is, for example, one or more Belleville washers. The other end of the spring 40 is housed in a ring 41 which bears against the bearing 30.

[0140] A spring 36 is arranged between the bearing 31 and the second pinion 12 to tend to press the elements constituting the vibrating against each other and against the bearing 30.

[0141] Reversible rotational linkage of the third and fourth gears

[0142] The fourth pinion 14 includes pins 140 capable of cooperating with clutch housings 130 of essentially complementary shape provided on the third pinion 13 such that when the pins 140 are housed in the clutch housings 130, the fourth pinion 14 and the third pinion 13 are rotationally linked. The pins 140 and the clutch housings 130 thus constitute means of rotationally linking the third 13 and the fourth 14 pinions.

[0143] The clutch housings 130 each extend along a portion of a circle whose center lies on the axis of rotation of the third pinion 13. They thus form sort of "beans".

[0144] In this embodiment, the pins 140 are cylindrical. In variations, the shape of the pins 140 and the clutch housings 130 may be chosen such that as soon as the fourth pinion 14 tends to rotate relative to the third pinion 13, the pins 140 tend to move out of the clutch housings 130, causing the fourth pinion 14 to move away from the third pinion 13 along its axis of rotation. The pins 140 are then not cylindrical but are ogive-shaped. This principle, known to those skilled in the art, is described, for example, in patent documents FR 2 881 366 and FR 2 918 592. Rotational immobilization of the fourth pinion

[0145] The fourth pinion 14 also includes first locking dogs 141 of complementary shape to second locking dogs 17 fixed relative to the casing 20 of the drill.

[0146] Movement of the fourth pinion between its engaged and immobilized positions

[0147] The device includes a sliding shaft 42. This sliding shaft 4 is housed in the casing 20 and extends parallel to the spindle 10.

[0148] The sliding shaft 42 comprises a first portion 420 and a second portion 421 fitted one into the other and linked in rotation and translation along the longitudinal axis of the sliding shaft 42. The sliding shaft 42 is movable in rotation and translation relative to the housing 20 along its longitudinal axis. For this purpose, it is guided by means of a bearing 422 relative to the housing 20 and is guided by means of bearings 423 relative to the third pinion 13, which is itself guided in rotation relative to the casing 20 by means of a bearing 424.

[0149] The fourth pinion 14 is mounted to rotate freely on the sliding shaft 420 by being placed between the first 420 and second 421 potions in such a way that it is linked in translation to the sliding shaft 42 along the axis of rotation of the latter.

[0150] Thus, the fourth pinion 14, and the sliding shaft 42, can take:

[0151] - an engaged position (illustrated in [Fig.2]) in which the 140 pawns are housed in the clutch housings 130 and the first locking dogs 141 do not cooperate with the second locking dogs 17 so that the fourth pinion 14 is rotationally linked with the third pinion 130 and is free to rotate relative to the housing 20, and

[0152] - an immobilized position (illustrated in [Fig.3]) in which the pawns 140 do not cooperate with the clutch housings 130 and the first locking dogs 141 cooperate with the second locking dogs 17 so that the fourth pinion 14 is immobile in rotation relative to the housing 20 and is not rotationally bound with the third pinion 13.

[0153] The third pinion 13 is guided in rotation and linked in translation relative to the housing 20 by means of the bearing 424.

[0154] The sliding shaft 42 is guided in rotation and translation relative to the third pinion 13 by means of the bearings 423.

[0155] The sliding shaft 42 has a grooved portion along its longitudinal axis on which is mounted a unidirectional clutch 43 which is also linked to the third pinion 13.

[0156] The one-way clutch 43 is configured such that:

[0157] - the third pinion 13 is not rotationally bound with the sliding shaft 42 when the The motor's rotor R rotates in the direction of operation, and

[0158] - the third pinion 13 is rotationally linked with the sliding shaft 42 when the rotor R the motor rotates in the opposite direction to the direction of work.

[0159] Holding the fourth pinion in the immobilized position

[0160] The drill includes means for retaining the fourth pinion 14 in its engaged position. These retaining means include a magnetic attraction element exerting a force on the fourth pinion 14, when it is in its engaged position, to maintain it in that engaged position.

[0161] This magnetic attraction element comprises a permanent magnet 44 coaxial with the sliding shaft 42 and located at one of its ends.

[0162] The end of the sliding shaft 42 oriented towards the side of the magnet 44 carries a washer 45 capable of bearing against the magnet 44 when the fourth pinion 14 is in the engaged position.

[0163] In the preferred embodiment described herein, the magnet 44 therefore acts indirectly on the fourth pinion 14 via the washer 45 and the sliding shaft 42. In a variant, the magnet 44 could act directly on the fourth pinion 14.

[0164] This magnet 44 may be an electromagnet, although this is not mandatory.

[0165] Thus, the magnet can be deactivated at any time during the drilling or deployment stroke without having to change the position of the first deployment end stop and thereby cause premature spindle retraction. This can be useful if the thickness to be drilled varies from one hole to the next. The actual drilling depth can then be programmed for each hole, rather than the depth corresponding to the deepest hole to be drilled. This can prevent the drill bit from overextending beyond the drilled surface and thus reduce the drilling cycle time.

[0166] Displacement of the fourth pinion from its engaged position to its stationary position

[0167] The drill includes means for moving the fourth pinion 14 from its engaged position to its immobilized position. These means of movement include a first elastic return element exerting on the fourth pinion 14 a force tending to move it from its engaged position to its immobilized position, and when it is in its immobilized position, a force maintaining the fourth pinion 14 in its immobilized position.

[0168] This elastic return element comprises, in this embodiment, a compression spring 46 arranged around the magnet 44 and bearing on one side against a calibration stop 47 and on the other side against the washer 45. The calibration stop 47 can be moved in translation relative to the housing 20 by acting on an adjustment knob 470 in order to calibrate the spring 46.

[0169] Deactivation of the means for holding the fourth pinion in its position immobilized by powering the electromagnet

[0170] The drill includes means for deactivating the holding effect of the holding means, i.e. the magnet 44, of the fourth pinion 14 in the engaged position.

[0171] When the magnet 44 is an electromagnet, these deactivation means may include means for supplying electricity to the electromagnet 44 so as to cancel the magnetic attraction it generates. In this case, the drill control means are configured to control the deactivation means so that they supply power to the magnet 44 when it is desired to trigger the retraction of the spindle 10. A spindle position sensor 10 may, for example, be used in this case to detect when the spindle deployment has reached the depth of Desired drilling. Monitoring the evolution of the motor current over time can also be used to detect, during the drilling of a through hole, the moment the drill bit breaks through, in order to trigger retraction. Monitoring the evolution of the motor current over time can also be used when retraction is to be initiated after the spindle 10 has fully extended, that is, when the first 18 and second 37 extension stops are in contact, to detect the moment these stops come into contact with each other.

[0172] Deactivation of the means for holding the fourth pinion in its position immobilized by lever

[0173] Alternatively, the means for deactivating the holding effect of the holding means of the fourth pinion 14 in the engaged position include a lever 48 capable of transmitting to the fourth pinion 14 a repulsive force greater than the magnetic attraction force transmitted to the fourth pinion 14 by the magnetic attraction element 44.

[0174] This lever 48 is mounted to rotate freely relative to the housing 20 on an axis 49 orthogonal to the axis of the spindle 10.

[0175] A first end of the lever 48 is in contact with the ring 4L The second end of the lever 48, opposite to the first end, is housed in a light 500 provided by a pusher 50.

[0176] The pusher 50 is free to move in translation within the housing 20 along the axis of the sliding shaft 42 with which it is coaxial. The pusher 50 includes a housing 501 for the washer 45, which is mounted thereon for translational movement, and includes a bearing surface 502 against which the face of the washer 45 facing the magnet 44 can bear. As will be described in more detail later, the pusher 50 is capable of pushing the washer 45 a short distance sufficient to disengage the washer from the magnet, and then the spring 46 completes the movement of the sliding shaft in its stationary position.

[0177] Lever 48 is capable of taking:

[0178] - a neutral state in which the pin 10 does not transmit any force to the lever 48 and the lever 48 does not transmit the repulsive force to the fourth pinion 14 so that the fourth pinion 14 is held in the engaged position by the magnet 44. The neutral state is maintained when the spindle 10 is moved on the predetermined deployment stroke and on the predetermined retraction stroke.

[0179] - a state of repulsion, taken at the end of a deployment of the pin 10 on the whole of the predetermined deployment stroke, under the effect of a rotation of the rotor R in the working direction, in which the lever 48 transmits the repulsive force to the fourth pinion 14 so as to counter the magnetic attraction force transmitted by the magnet 44 to the fourth pinion 14.

[0180] The first pinion 11 is mounted to move in translation along the spindle 10 against the effect of the spring 40. A rotation of the spindle 10 in the direction of work, when the first end-of-deployment stop 18 is in contact with the second end-of-deployment stop 37 induces a translational drive, along the spindle 10, of the first pinion 11 by the second pinion 12, the first pinion 11 acting via the ring 41 on the lever 48 to place it in its repulsive state.

[0181] This lever 48 constitutes an actuator which could possibly be replaced by an electric cylinder fulfilling the same function.

[0182] Means of moving the fourth pinion from the stationary position to the engaged position - Cam

[0183] The drill includes means for moving the fourth pinion 14 from the stationary position to the engaged position.

[0184] These means of movement include in this embodiment a cam system 51.

[0185] These means of transport include:

[0186] - the control means 300 configured to reverse the direction of rotation of the motor so that the rotor R rotates in the opposite direction to the working direction when the first end stop of retraction 19 comes to rest against the second end stop of retraction, i.e. the second pinion 12;

[0187] - the wandering tree 42;

[0188] - the unidirectional clutch 43, the third pinion 13 and the rotor R;

[0189] - a cam 510 shaped to induce, during a rotation of the rotor R in the direction In the opposite direction of work, a movement of the sliding shaft 42 and the fourth pinion 14 from the immobilized position to the engaged position.

[0190] The cam 510 is annular and coaxial with the sliding shaft 42. It is fixed by relative to the housing 20 and is located on the side of the sliding shaft 42 opposite to the one where the washer 45 is located.

[0191] The cam 510 has a ramp 5100 whose development is parallel to the axis of rotation of the sliding shaft 42. It thus has a projecting end 5101 in the direction of the fourth pinion 14 and a hollow end 5102 in the opposite direction.

[0192] The ramp 5100 is in contact with a lug 52 linked in rotation to the sliding shaft 42 along the axis of rotation of the sliding shaft 42.

[0193] The cam 512 has, at the junction between the protruding end 5101 and the end In recess 5102, a housing 5104 for the lug 52. This housing 5104 is recessed relative to the recessed end 5102 and has a ramp 5105 which rises progressively to the recessed end 5102 of the cam 510.

[0194] These means of displacement also include a ring 53 coaxial with the sliding shaft 42.

[0195] This ring 53 is mobile in translation and rotation along the axis of rotation of the sliding shaft 42 relative to the sliding shaft 42.

[0196] Ergot 52 is:

[0197] - linked in translation and rotation to the ring 53,

[0198] - rotationally linked to the sliding shaft 42, and

[0199] - partially linked in translation with respect to the sliding shaft 42 along the axis of rotation of it.

[0200] As will become clearer later, the lug is partially translationally bound to the sliding shaft 42 in that it is not directly and rigidly bound to it over the entire translational stroke of the lug. However, the lug is indirectly and elastically bound to the sliding shaft in translation due to the use of a spring 54 described below. In an alternative embodiment, the lug could optionally be directly and / or rigidly bound to the sliding shaft in translation.

[0201] For this purpose, the lug 52 is mounted in a groove 423 formed at the end of the sliding shaft 42 opposite to that at which the washer 45 is located.

[0202] An elastic element, such as a compression spring 54, is arranged between the ring 53 and a shoulder of the sliding shaft 42 in such a way that a rotation of the rotor R in the opposite direction to the working direction tends to move the ring 53 towards the sliding shaft 42 and to compress the elastic element 54 between the ring 53 and the shoulder of the sliding shaft 42 if the pins 140 of the fourth pinion 14 do not extend into the clutch housings 131 of the third pinion 13 during the movement of the lug 52 against the cam 510. This will be explained in more detail later with the description of the operation of the drill.

[0203] The drill includes means for preventing the rotation of the sliding shaft 42 when the fourth gear 14 is in the engaged position. These means are configured such that the path of the lug 52, during the transition of the fourth gear 14 from its engaged position to its locked position, is parallel to the axis of the sliding shaft 42. This will be explained in more detail later with the description of the drill's operation.

[0204] This implementation ensures synchronization of the lug 52 to place the lug 52 in the axis, i.e. in the extension along the longitudinal axis of the sliding shaft, of the housing 5104 of the cam 510 when the fourth pinion 14 is in the engaged position, following a rotation of the rotor R in the opposite direction to the working direction which has moved the fourth pinion 14 from its immobilized position to its engaged position.

[0205] These immobilization means include the following elements.

[0206] The ring 53 and the lug 52 are housed in a bell 56 fixed relative to the housing 20 and comprising a light 560 in which the lug 52 can move when it moves along the cam 510.

[0207] This light 560 includes a lateral bearing surface 561 against which the lug 52 comes to rest, or near which the lug 52 comes, when it passes beyond the projecting end 5101 of the cam 510 towards the hollow end 5102 under the effect of a rotation of the rotor R in the opposite direction to the direction of work, as will be explained in more detail later.

[0208] When the fourth pinion 14 is in the engaged position, the lug 52 is in the axis of the housing 5104 of the cam 510 between the lateral bearing surface 561 of the slot 560 and the junction surface 5103 which extends between the protruding end 5101 of the cam 510 and the recessed end 5102 of the cam 510. The sliding shaft 42 is thus immobilized in rotation.

[0209] When the fourth pinion 14 is in the immobilized position, the lug 52 is in the housing 5104 of the cam 512. 6.1.2. Operation

[0210] This type of drill can also be used to make holes with or without countersinking at the hole entry. i. Drill stopped before starting

[0211] Before starting the drill to perform a drilling operation, the drill is, where appropriate, fixed on a drilling grid, in a centering hole located in the axis of the hole to be drilled.

[0212] As long as the start button is not activated by the operator, the spindle 10 is fully retracted so that the first end stop of retraction 19 is in contact with the second pinion 12, which constitutes the second end stop of retraction.

[0213] The fourth pinion 14 is in its engaged position in which it is held in position by the magnet 44 insofar as the washer 45 is in contact with the magnet 44, which exerts on it a magnetic attraction force against the compression spring 46.

[0214] The lug 52 is located in the axis of the housing 5104 of the hollow end 5102 of the cam 510, and is away from it, between the lateral bearing surface 561 of the opening 560 and the junction surface 5103 between the protruding end 5101 of the cam 510 and the hollow end 5102 of the cam 510 (cf. position A).

[0215] Lever 48 is in its neutral state. ii. Drilling operation ii.l. Deployment of the spindle

[0216] To start the drill, an operator activates the start button to initiate the drilling operation.

[0217] The motor starts so that the rotor R is driven in rotation in the working direction, i.e. drilling direction.

[0218] The pinion 15 located at the end of the rotor R drives the third pinion 13 in rotation.

[0219] The fourth pinion 14, which is rotationally linked with the third pinion 13, is driven in rotation.

[0220] The first pinion 11 is driven in rotation by the third pinion 13 so that the spindle 10 is driven in rotation about its longitudinal axis.

[0221] The second pinion 12 is driven in rotation by the fourth pinion 14.

[0222] The reduction ratio between the first 11 and the third pinion 12 is different of the reduction ratio between the second pinion 12 and the fourth pinion 14. Thus, taking into account the helical connection between the second pinion 12 and the spindle 10, the spindle 10 is driven in translation along its axis and deploys out of the housing 20 until the first end-of-deployment stop 18 is in contact with the ball stop 37 which constitutes the second end-of-deployment stop.

[0223] During drilling, the following stacked parts are used to generate the reciprocating feed component (vibrating feed): - the outer ring of the bearing 30, itself linked to the housing 20 of the drilling device; - the first track 33 of the vibrating; - the 34 rollers of the vibrating roller; - the second track 35 of the vibrating; - the first pinion 11 generating the rotation of the spindle 10; - the second pinion 12 generating the feed of the spindle 10, this pinion 12 is separated from the first pinion 11 by a row of balls 320 acting as a stop; - the return spring 36.

[0224] During drilling action, due to the rotation of the first pinion 11 relative to the housing 20, the tracks 33, 35 of the vibrator rotate relative to each other, this inducing an alternating axial movement of the first pinion 11. This movement is transmitted to the second pinion 12 and then to the spindle 10, this inducing the alternating feed component at the level of the drill lips.

[0225] During this period, the drill is driven along a helical trajectory with an appropriate cutting speed and vibrating feed rate, thus achieving the expected drilling.

[0226] ii.2. End of spindle deployment: passage of the fourth pinion into position immobilized

[0227] During the finalization of the countersink, the first end-of-deployment stop 18 comes into contact with the second end-of-deployment stop, i.e., in this embodiment, the ball stop 37. The axial movement of the spindle 10 is interrupted while the spindle 10 continues to rotate through an angle of approximately one revolution. This allows the countersink surface to be finished without waviness.

[0228] Meanwhile, the second pinion 12 continues to rotate. With the spindle 10 axially stationary, the second pinion 12 moves under the action of the spindle 10's thread in the direction of the first deployment end stop 18. To allow this movement, the countersink finishing spring 40 compresses, giving the countersink time to be completed.

[0229] When the milling end-setting spring 40 can no longer be compressed, the second pinion 12 stops moving axially.

[0230] The stiffness of the countersink finishing spring 40 is, however, sufficiently strong so that it does not collapse during the drilling action and does not disrupt the generation of the reciprocating feed component.

[0231] When the spring 40 is compressed, the ring 41 acts on the lever 48 and moves the lever 48 from its neutral state to its repulsive state by pivoting it around the axis 49. During this movement, the lever 48 exerts a force on the movable pusher 50 and translates it in the direction of the fourth pinion 14. The pusher 50 drives the washer 45 in the same direction, which tends to move away from the magnet 44. When the repulsive force transmitted by the lever 48 to the washer 45, combined with the force applied by the spring 46 to the washer 45, becomes greater than the magnetic attraction force exerted by the magnet 44 on the washer 45, the compression spring 46 moves the washer 45, the sliding shaft 42, and the fourth pinion 14 to its immobilized position and holds the fourth pinion 14 in this position.

[0232] As an alternative to using the lever 48, the washer 45 is detached from the magnet 44 by the control means 300 which controls the supply of electricity to the magnet 44 to inhibit the magnetic attraction force it produces:

[0233] - either to the detection by the control means of the arrival of the first deployment end stop 18 on the second deployment end stop 37 by increasing the consumption of the electric motor;

[0234] - either before the first 18 and second 37 deployment end stops are in contact but after drilling to a certain depth measured by the angle of rotation traveled by the rotor R of the motor since the start of the drill.

[0235] During the movement of the fourth pinion 14 from its engaged position to its immobilized position, the lug 52 moves in translation along the axis of the shaft the portable 42 until it comes to rest in the housing 5104 of the cam 510 and being guided there if necessary by the ramp 5105 (see position B). ii.3. Pin retraction

[0236] Given that the fourth pinion 14 is in its immobilized position, the fourth pinion 14 is immobilized in rotation, and the second pinion 12 is also immobilized in rotation.

[0237] Thus, the spindle 10, which continues to be driven in rotation by the third pinion 13 and the first pinion 11, moves in translation along its axis in the direction of a retraction inside the housing 20.

[0238] ii.4. End of spindle retraction: passage of the fourth pinion into position engaged

[0239] The retraction of the spindle 10 takes place until the first end-of-retraction stop 19 comes into contact with the second pinion 12, which constitutes the second end-of-retraction stop.

[0240] The control means 300 detect that the spindle is thus completely retracted, for example by following the evolution over time of the motor current.

[0241] When the control means 300 detect that the spindle 10 is fully retracted, they drive the motor so that the rotor R rotates in the opposite direction to the working direction.

[0242] The sliding shaft 42 is then driven in rotation by the third pinion 13 and by the unidirectional clutch 43.

[0243] The lug 52 is then driven in rotation by the sliding shaft 42. It comes out of the housing 5104 of the cam 510 and then slides against the ramp 5100 of the cam 510 towards its protruding end 5101 and translates towards the washer 45. The movement of the lug 52 along the cam 510 induces a movement of the ring 53 towards the fourth pinion 14.

[0244] If the pins 140 of the fourth pinion 14 extend into the clutch housings 130 of the third pinion 13, then the lug 52, by moving towards the washer 45, pushes the ring 53 and the spring 54, which move the fourth pinion 14 into its engaged position against the effect of the spring 46. The fourth pinion 14 is then held in this engaged position by the magnet 44 with which the washer 45 is in contact. The washer 45 comes into contact with the magnet 44 slightly before the lug 52 passes beyond the protruding end 5101 of the cam 510.Thus, at the end of the movement of the fourth pinion 14 towards its engaged position, the lug 52 passes beyond the protruding end 5101 of the cam 510, then moves slightly towards the cam 512, under the effect of the release of the spring 54 and the movement of the ring 53 towards the cam 510, so that it is in the axis of the housing 5104 of the cam 510 between the bearing surface 561 of the slot 560 and the connecting surface 5103. between the protruding end 5101 and the recessed end 5102 of the cam 510, while remaining away from the housing 5104 (position A). The lug 52 is thus blocked from rotation between these two surfaces 561, 5103 so that the sliding shaft 42 is immobilized from rotation.

[0245] If the pins 140 of the fourth pinion 14 do not extend into the clutch housings 130 of the third pinion 13, then the pins 140 come to rest against the third pinion 13 outside the clutch housings 131 and the ring 53 compresses the spring 54 against the shoulder of the sliding shaft 42. The probability of this situation occurring is very low given the implementation of the "bean-shaped" clutch housings 130 which maximizes the chances that the pins 140 are always opposite the corresponding clutch housings 130.

[0246] Meanwhile, the third pinion 13 continues its rotation, the fourth pinion 14 is driven at a different frequency than the third pinion 13 due to the difference in the number of teeth between the first 11 and second 12 pinions, so that the pins 140 synchronize with the clutch housings 131 of the third pinion 13. When the pins 140 are synchronized with the clutch housings 131, i.e., they are aligned with each other, the spring 54 relaxes and pushes the sliding shaft 42, which completes its movement until its washer 45 comes into contact with the magnet 44. The fourth pinion 14 is then held in its engaged position by the magnet 44. The washer 45 comes into contact with the magnet 44 slightly before the lug 52 passes beyond the protruding end 5101 of the 510 cam.Thus, at the end of the movement of the fourth pinion 14 towards its engaged position, the lug 52 passes beyond the protruding end 5101 of the cam 510, then moves slightly towards the cam 512 under the effect of the release of the spring 54 and the movement of the ring 53 towards the cam 510, so that the lug 52 is located on the axis of the housing 5104 of the cam 510 between the bearing surface 561 of the slot 560 and the connecting surface 5103 between the protruding end 5101 and the recessed end 5102 of the cam 510 while remaining away from the housing 5104 (position A). The lug 52 is thus prevented from rotating between these two surfaces 561, 5103 and the sliding shaft 42 is prevented from rotating.

[0247] The retraction can be stopped after a predetermined angle of rotation of the lug relative to the cam. This angle can be measured by the motor's angle sensor, taking into account the reduction ratio between the motor and the sliding shaft, and is considered by the drill's control means. In the illustrated embodiment, the cam is actually a double cam with two ramps, each extending through 180°, and the lug is a double lug, each end of which acts on a different cam. Therefore, half a turn of the double lug relative to the cam may be sufficient to move the fourth gear from its stationary position to its engaged position. However, a full rotation may be required depending on the reliability of the reset.

[0248] Lever 48 is also in its neutral state.

[0249] The drill is then in the state it was in before its start-up so that a new drilling cycle can be started by pressing the start button. 6.1.3. Variant#: fork

[0250] In a variant illustrated in figures 5 and 6, and not covered by the set of claims, the means for moving the fourth pinion 14 from its immobilized position to its engaged position do not include the cam system described above.

[0251] Alternatively, they include a 60 range.

[0252] This fork 60 is traversed at one of its ends by the pin 10. At the other of its ends, the fork 60 is linked in translation to the sliding shaft 42. The fork 60 is also traversed by a rotating stop shaft 67.

[0253] The fork 60 is movable in translation between:

[0254] - an engaged position, illustrated in [Fig. 5], in which the fourth pinion 14 is in the engaged position, and

[0255] - a stationary position, illustrated in [Fig. 6], in which the fourth pinion 14 is in its immobilized position.

[0256] The device includes a lock 62. This lock 62 includes at one of its ends a hook 620 and at the other of its ends a cam 621.

[0257] The hook 620 is capable of cooperating with an attachment point 64 linked to the fork 60.

[0258] The lock 62 is mounted to rotate freely about an axis 63 linked to the housing 20 between:

[0259] - a release position, illustrated in [Fig. 5], in which the hook 620 does not does not cooperate with the attachment point 64, so it does not hold the fork 60 in its immobilized position, and

[0260] - a locking position, illustrated in [Fig. 6], in which the hook 620 cooperates with the hook point 64 so that it keeps the fork 60 in its immobilized position.

[0261] The fork 60 carries a spring blade 65, which tends to keep the lock 62 in its locked position.

[0262] A compression spring 66 is interposed between the first end stop of retraction 19 and the fork 60.

[0263] The first end stop of retraction 19 includes a conical portion 190 oriented towards the side of the lock 62.

[0264] The hook 620 includes a ramp 6200 intended to act on the hooking point 64.

[0265] Throughout the deployment of the spindle 10 out of the housing 20, the fourth pinion 14 is held in its engaged position by the magnet 44. The fork 60 is in its engaged position, in which it is held by the magnet 44, and in which the hook 620 does not cooperate with the hook point 64, which is in contact with the ramp 6200.

[0266] During the movement of the fourth pinion 14 from its engaged position to its immobilized position under the effect of the release of the spring 46, the fork 60 is progressively driven in translation by the sliding shaft 42 towards the first end stop of retraction 19. During this movement, the hook point 64 slides against the ramp 6200 of the lock 62, which induces a rotation of the lock 62 around the axis 63 allowing the progressive passage of the hook point 64 into the hook 620.

[0267] When the fourth pinion 14 is in its immobilized position, the fork 60 is in its immobilized position and the lock 62 is in its locked position in which it is held by the spring blade 65. The hook point 64 is then trapped in the hook 620 so that the fork 60 is held in its immobilized position.

[0268] Given that the fourth pinion 14 is in its immobilized position, the spindle 10 retracts.

[0269] During the final portion of the spindle 10's retraction stroke, the first end stop compresses the spring 66. Then, the conical portion 190 of the first end stop 19 acts progressively on the cam 621 of the lock 62, causing the lock 62 to rotate around the axis 63. This rotation of the lock 62 induces a progressive movement of the lock 62 from its locked position to its released position. When the lock 62 reaches its released position, the hook 620 releases the engagement point 64, so that the fork 60 is driven in translation along the spindle 10 by the release of the compression spring 66. The fork 60 then drives the sliding shaft 42 in translation, so that the fourth pinion 14 gradually moves from its stationary position to its engaged position.

[0270] If, during the movement of the fourth pinion 14 from its stationary position to its engaged position, the pins 140 of the fourth pinion 14 extend into the continuation of the clutch housings 130 of the third pinion 13, then the fork 60 moves the sliding shaft 42 and the fourth pinion 14 into its engaged position under the effect of the release of the spring 66. The fourth pinion 14 is then held in this engaged position by the magnet 44.

[0271] If, during the movement of the fourth pinion 14 from its stationary position to its engaged position, the pins 140 of the fourth pinion 14 do not extend into the clutch housings 130 of the third pinion 13, then the pins 140 bear against the third pinion 13 outside the clutch housings 131 and the spring 66 partially relaxes. Then, as in the case of the cam system, when the pins 140 synchronize with the clutch housings 131, the spring 66 fully relaxes the fork 60 which moves the sliding shaft 42 until the fourth pinion 14 is placed in its engaged position in which it is held by the magnet 44.

[0272] In this variant, no second retraction end stop is implemented. The retraction end position of the spindle 10 corresponds to its position when the fourth pinion 14 leaves its immobilized position.

[0273] 6.2. Second embodiment: device with bistable element 6.2.1. Architecture

[0274] An example of an embodiment of a drill according to the invention comprising a bistable element is presented in relation to Figures 7 to 10.

[0275] Figures 2 (a), 2 (b), 3 (a), 3 (b) and 4 of the preceding embodiment are also to be taken into consideration with regard to the displacement and positioning of the lug 52 relative to the cam 510. Actuation button

[0276] The drill conventionally includes a start button (not shown).

[0277] Such a start button does not require sustained pressure from the operator as required by a trigger.

[0278] The operator presses the start button once to initiate a drilling operation. The drilling operation then proceeds until the drill stops automatically. However, an emergency stop button is provided for early shutdown if necessary. Ordering methods

[0279] The drill also conventionally includes control means 300, such as a controller internal or external to the drill housing, comprising electronic and logic components, which allow the operation of the drill to be controlled. Such a controller is conventional in itself except that it is configured and programmed to allow the control of a drill according to the invention.

[0280] Motorized spindle drive transmission

[0281] Such a drill conventionally comprises a housing 20. It preferably also comprises means for fixing the housing 20 to grids of Drilling. Such drilling grids are known in themselves and are therefore not described in more detail here.

[0282] The housing 20 contains a spindle 10 that can be deployed outside the housing 20. This spindle 10 is adapted to carry, at one of its ends, a cutting tool such as a drill bit. This drill bit is coaxial with the spindle and rotationally linked to it.

[0283] The pin 10 includes longitudinal grooves 101 and is threaded 102 along its entire length.

[0284] Pin 10 is equipped with:

[0285] - of a first end-of-deployment stop 18 capable of providing support against a second fixed end-of-deployment stop, translationally relative to the housing 20 along the axis of the spindle 10; in this case, the second end-of-deployment stop is constituted by a first pinion 11, and

[0286] - of a first end stop for retraction 19 capable of bearing on a second fixed end stop for retraction in translation relative to the housing 20 along the axis of the spindle 10, in this case the second end stop for retraction is constituted by the end of a second pinion 12.

[0287] The first 18 and second 11 deployment end stops define a predetermined deployment stroke of the pin 10.

[0288] The first 19 and second 12 retraction end stops define a predetermined retraction stroke of the spindle 10.

[0289] The drill bit is intended to be secured to the spindle 10 on the side of the first end stop of retraction 19.

[0290] The drill includes an electric motor (not shown) equipped with a rotor R.

[0291] The drill includes a T-transmission. This T-transmission is interposed between the rotor R of the motor and the spindle 10. It is capable of transforming a rotational movement of the rotor R in the working direction (i.e. drilling direction) into a rotational movement or a combined rotational and translational movement of the output spindle 10 along the same axis, i.e. its longitudinal axis X.

[0292] This transmission T includes:

[0293] - the first pinion 11 coaxial with the spindle 10 and provided with internal splines cooperating with the external longitudinal grooves of the spindle 10 (the first pinion 11 and the spindle 10 are thus linked by a linear connection along the longitudinal axis of the spindle 10);

[0294] - the second pinion 12 coaxial with the spindle 10 and provided with an internal thread cooperating with the thread 102 of the spindle 10 (the second pinion 12 and the spindle 10 are thus linked by a helical connection along the longitudinal axis of the spindle 10);

[0295] - a third pinion 13 with an axis parallel to the spindle 10, guided in rotation by relative to the crankcase, engaging with the first pinion 11 according to a first ratio of transmission and driven in rotation by the drill motor directly or via any type of gear(s), in particular here a pair of 150 bevel gears;

[0296] - a fourth pinion 14 with an axis parallel to the spindle 10, guided in rotation and in translation relative to the casing, engaging with the second pinion 12 according to a second transmission ratio different from the first ratio. Optional vibrator

[0297] In the figures, the drill is shown in its variant without a vibrator. However, as in the first embodiment with a magnet, the drill can optionally include a vibrator.

[0298] The drill can also include, as in the first magnetic embodiment, a ball stop playing in particular the role of a second end-of-deployment stop.

[0299] Such a vibrating and ball stop are not described here in further detail because their structures may be identical to those described in relation to the first magnetic embodiment.

[0300] The assembly consisting of the spindle 10, the first pinion 11 and the second pinion 12 is guided in rotation relative to the housing 20 by means of a bearing 30 and a bearing 31. A ball thrust bearing 32 essentially prevents friction between the first 11 and second 12 pinions.

[0301] A track 33, without surface undulation, comes to rest against the bearing 30. Rollers 34 come to rest against the first track 33.

[0302] A spring 36 is arranged between the bearing 31 and the second pinion 12 to tend to press the first pinion 11, the second pinion 12, the rollers 34 and the track 33 against each other and against the bearing 30.

[0303] Reversible rotational linkage of the third and fourth gears

[0304] The fourth pinion 14 includes pins 140 capable of cooperating with complementaryly shaped clutch housings 130 provided on the third pinion 13 such that when the pins 140 are housed in the clutch housings 130, the fourth pinion 14 and the third pinion 13 are rotationally linked. The pins 140 and the clutch housings 130 thus constitute means of rotationally linking the third 13 and the fourth 14 pinions.

[0305] The clutch housings 130 each extend along a portion of a circle whose center is located on the axis of rotation of the third pinion 13. They thus form sort of "beans".

[0306] The shape of the first pins 140 and the clutch housings 130 is chosen such that as soon as the fourth pin 14 tends to rotate relative to the third pin 13, the pins 140 tend to come out of the clutch housings 130 inducing that the fourth pinion 14 tends to move away, along its axis of rotation, from the third pinion 13. The pins 140 thus appear for example in the form of ogives. This principle, known in itself to a person skilled in the art, is described for example in patent documents FR 2 881 366 and FR 2 918 592. Rotational immobilization of the fourth pinion

[0307] The fourth pinion 14 also includes first locking dogs 141 of complementary shape to second locking dogs 17 fixed relative to the casing 20 of the drill.

[0308] Movement of the fourth pinion between its engaged and immobilized positions

[0309] The device includes a sliding shaft 42. This sliding shaft 42 is housed in the casing 20 and extends parallel to the spindle 10.

[0310] The sliding shaft 42 is free to rotate and translate relative to the housing 20 along its longitudinal axis. For this purpose, it is guided by means of two bearings 420, 421. Bearing 420 guides the sliding shaft 42 relative to the housing 20, while bearing 421 guides the sliding shaft 42 in the third pinion 13, which is itself guided in rotation within the housing by means of bearings 422.

[0311] The fourth pinion 14 is mounted to rotate freely on the sliding shaft 42 and is linked in translation to the sliding shaft 42 along the axis of rotation of the latter in such a way that the fourth pinion 14, and the sliding shaft 42, can take:

[0312] - an engaged position (illustrated in [Fig.7]) in which the 140 pawns are housed in the clutch housings 130 and the first locking dogs 141 do not cooperate with the second locking dogs 17 so that the fourth pinion 14 is rotationally linked with the third pinion 130 and is free to rotate relative to the housing 20, and

[0313] - an immobilized position (illustrated in [Fig.9]) in which the pawns 140 do not cooperate with the clutch housings 130 and the first locking dogs 141 cooperate with the second locking dogs 17 so that the fourth pinion 14 is immobile in rotation relative to the housing 20 and is not rotationally bound with the third pinion 13.

[0314] The third pinion 13 is guided in rotation and linked in translation relative to the housing 20 by means of the bearings 424.

[0315] The sliding shaft 42 is guided in rotation and translation on the one hand relative to the housing 20 and on the other hand relative to the third pinion 13 respectively by means of the bearings 420 and 421.

[0316] The sliding shaft 42 has a grooved portion along its longitudinal axis on which is mounted a unidirectional clutch 43 which is also linked to the third pinion 13.

[0317] The one-way clutch 43 configured such that:

[0318] - the third pinion 13 is not rotationally linked with the sliding shaft 42 when the The motor's rotor R rotates in the direction of operation, and

[0319] - the third pinion 13 is rotationally linked with the sliding shaft 42 when the rotor R the motor rotates in the opposite direction to the direction of work.

[0320] Movement and holding of the fourth pinion in the immobilized position

[0321] The drill includes means for holding the fourth pinion 14 in its engaged position and in its immobilized position, and means for moving the fourth pinion 14 from its engaged position to its immobilized position, and vice versa.

[0322] These holding and displacing means comprise a bistable elastic element 70 capable (illustrated in [Fig. 7]) of assuming two stable states, namely:

[0323] - a clutch state in which it holds the fourth pinion 14 in its engaged position, and

[0324] - a state of immobilization (illustrated in [Fig.9]) in which it maintains the fourth pinion 14 in its immobilized position.

[0325] This bistable elastic element 70 comprises at least one long element having two ends. One end is articulated at at least one first articulation point 700 on the housing 20. The other end is articulated at at least one second articulation point 701 on the sliding shaft 42. The at least one long element is compressible in a direction collinear with a line passing through its two ends and has a predetermined stiffness. The sliding shaft 42 is movable relative to the housing 20 between positions corresponding to the engaged and immobilized positions of the fourth pinion 14. The second articulation point 701 on the sliding shaft 42 occupies, in the engaged and immobilized states, substantially symmetrical positions with respect to a median plane PM perpendicular to the sliding shaft 42 and passing through the first articulation point 700 on the housing 20.The distance between the ends of at least one long element taken in a relaxed state being greater than the distance between the first 700 and second 701 articulation points when the second articulation point 701 to the sliding shaft 42 is in the median plane PM. .

[0326] Between its two stable states, the bistable element 70 can assume a median state, illustrated in [Fig. 8], in which the second articulation point 701 lies in the median plane. Between the median state and the engaged state, the bistable element 70 tends to move the fourth pinion 14 towards its engaged position. Between the median state and the disengaged state, the bistable element 70 tends to move the fourth pinion 14 towards its disengaged position.

[0327] At least one elongated element preferentially belongs to the group comprising:

[0328] - a metal blade whose compressibility results from its buckling;

[0329] - a component incorporating a spring whose compressibility results from compression said jurisdiction.

[0330] In this embodiment, the bistable elastic element comprises a bistable elastic washer 70.

[0331] More specifically, this bistable elastic washer 70 is connected to the housing 20 by a plurality of first articulation points 700. For this purpose, the outer circular peripheral contour 702 of the bistable elastic washer 70 is housed in a groove 200 fixed relative to the housing 20.

[0332] In addition, the bistable elastic washer 70 is connected to the sliding shaft 42 by a plurality of second articulation points 701. For this purpose, it includes a central circular hole 703 whose contour is housed in a groove 423 formed at a first end of the sliding shaft 42.

[0333] When the first end-of-deployment stop 18 is against the second end-of-deployment stop 11 and the rotor R is rotating in the direction of travel, the third 13 and fourth pinions 14 rotate relative to each other such that the ogive-shaped pins 140 and the clutch housings 131 induce a displacement of the fourth pinion 14 towards the immobilized position over a stroke that causes the second pivot points 701 of the bistable washer 70 on the sliding shaft 42 to pass the median plane PM and the bistable spring washer 70 to transition from its engaged state to its immobilized state. For this to occur, the length of the ogives must be greater than half the stroke of the sliding shaft between the engaged and immobilized positions.

[0334] Due to its stiffness, the bistable elastic washer 70 participates, beyond the passage of the median plane PM through the second articulation points 701, in moving the fourth pinion 14 towards its immobilized position.

[0335] When the fourth pinion 14 is in its immobilized position, it is supported against the housing in such a way that the bistable elastic washer 70 exerts on the sliding shaft 42 an elastic restoring force tending to maintain it, and the fourth pinion 14, in the immobilized position.

[0336] Displacement of the fourth pinion from its engaged position to its stationary position

[0337] The means for moving the fourth pinion 14 from its engaged position to its immobilized position include here not only the ogive pins 141 and the clutch housings 131 but also the bistable elastic washer 70.

[0338] However, alternatively, the pins may be cylindrical rather than ogival as in the first magnetic embodiment, and the means for moving the fourth pinion 14 from its engaged position to its position immobilized components may include an actuator capable of transmitting to the fourth pinion 14 a displacement force sufficient to bring the second articulation points 701 on the sliding shaft 42 beyond the median plane PM and to move the bistable elastic element 70 from its engaged state to its immobilized state. Such an actuator may have at least:

[0339] - a neutral state in which it does not transmit the displacement effort to the fourth pinion 14, the neutral state being maintained when the spindle 10 is moved through the predetermined extension stroke and the predetermined retraction stroke, and

[0340] - a state of displacement in which it transmits the force to the fourth pinion 14 of displacement, the state of displacement being taken, at the end of a deployment of the spindle 10 over the entire predetermined deployment stroke, under the effect of a rotation of the rotor R in the direction of work.

[0341] As in the previous embodiment, using the magnet, this actuator can include the lever (not shown here) which will have a first end connected in rotation to the housing 20 along an axis orthogonal to the spindle 10, and a second end capable of acting, directly or indirectly on the fourth pinion 14 to move it from its engaged position to its immobilized position over a sufficient stroke to bring the second articulation points 701 to the sliding shaft 42 to pass the median plane PM and to move the bistable elastic element 70 from its engaged state to its immobilized state.

[0342] In this lever-operated variant, the first pinion 11 is mounted to move linearly along the spindle 10 against the effect of a spring. A rotation of the spindle 10 in the working direction, when the first end-of-extension stop 18 is against the second end-of-extension stop 11, induces a linear drive along the spindle 10 of the first pinion 11 by the second pinion 12, the first pinion 11 acting on the lever to place it in its moving state.

[0343] Means of moving the fourth pinion from the immobilized position towards the Engaged position - Cam

[0344] The drill includes means for moving the fourth pinion 14 from the stationary position to the engaged position.

[0345] These means of movement include in this embodiment a cam system.

[0346] These means of transport include:

[0347] - the control means configured to reverse the direction of rotation of the motor so that the rotor R rotates in the opposite direction to the working direction when the first end stop of retraction 19 comes to rest against the second end stop of retraction 12;

[0348] - the wandering tree 42;

[0349] - the unidirectional clutch 43, the third pinion 13 and the rotor R;

[0350] - a cam 510 shaped to bring, during a rotation of the rotor R in the direction In the opposite direction of work, the second articulation points 701 of the bistable washer 70 to the sliding shaft 42 to pass the median plane PM, to move the bistable washer 70 into its engaged state, and to move the sliding shaft 42 and the fourth pinion 14 from the immobilized position to the engaged position.

[0351] The cam 510 is annular and coaxial with the sliding shaft 42. It is fixed relative to the housing 20 and is located on the side of the sliding shaft 42 where the bistable washer 70 is located.

[0352] The cam 510 has a ramp 5100 whose development is parallel to the axis of rotation of the sliding shaft 42. It thus has a projecting end 5101 in the direction of the fourth pinion 14 and a recessed end 5102 in the opposite direction.

[0353] The ramp 5100 is in contact with a lug 52.

[0354] The cam 512 has, at the junction between the projecting end 5101 and the recessed end 5102, a housing 5104 for the lug 52. This housing 5104 is recessed relative to the recessed end 5102 and has a ramp 5105 which rises progressively to the recessed end 5102 of the cam 510.

[0355] Ergot 52 is:

[0356] - rotationally linked to the sliding shaft 42, and

[0357] - partially linked in translation to the wandering tree 42.

[0358] For this purpose, the lug 52 is mounted in a housing 521 provided for this purpose in the sliding shaft 42 perpendicular to its axis. A compression spring 520 is interposed between the lug 52 and the bottom of the housing 521. This spring 520 tends to compress between the lug 52 and the bottom of the housing 521 when the lug 52 moves inside the housing 521 towards the third pinion 13.

[0359] As will become clearer later, the lug is partially translationally bound to the sliding shaft 42 in that it is not rigidly bound to it over the entire translational stroke of the lug. However, the lug is elastically and indirectly translationally bound to the sliding shaft due to the spring 520. In an alternative embodiment, the lug could optionally be directly and / or rigidly translationally bound to the sliding shaft.

[0360] Rotating the rotor R in the opposite direction to its working direction causes the lug 52 to move on the cam 510. Sliding along the ramp 5100 of the cam 510, the lug 52 follows a helical path along the axis of the sliding shaft 42 and moves the sliding shaft 42 translationally towards the engaged position of the fourth pinion 14. This movement causes the second pivot points 701 of the sliding shaft 42 to pass through the median plane PM and the bistable elastic element 70 to pass through in the engaged state. This induces a movement of the sliding shaft 42 and the fourth pinion 14 from the stationary position to the engaged position.

[0361] During this movement of the sliding shaft 42, the second articulation points 701 of the bistable washer 70 with the sliding shaft 42 pass the median plane PM. From the point of passing this plane, the bistable washer 70, due to its stiffness, contributes to the movement of the sliding shaft 42 to place the fourth pinion 14 in its engaged position.

[0362] When the fourth pinion 14 is in the engaged position, the wing is in contact with the third pinion 13 which acts as a stop in such a way that the bistable washer 70 exerts on the sliding shaft 42 an elastic restoring force tending to maintain the fourth pinion 14 in its engaged position.

[0363] The device includes means for immobilizing the sliding shaft 42 in rotation when the fourth pinion 14 is in the engaged position such that the trajectory of the lug 52 during the passage of the fourth pinion 14 from its engaged position to its immobilized position is parallel to the axis of the sliding shaft 42.

[0364] This implementation ensures synchronization of the lug 52 to position the lug 52 in line with, i.e., in line with, the longitudinal axis of the sliding shaft, the housing 5104 of the cam 510 when the fourth pinion 14 is in the engaged position following a rotation of the rotor R in the opposite direction to the direction of rotation that placed the fourth pinion 14 in its engaged position. This implementation thus prevents the lug from directly striking the cam and the pinion from returning to its immobilized position.

[0365] These immobilization means include the following elements.

[0366] In addition, the lug 52 is housed in a bell 56 fixed relative to the housing 20 and comprising a light 560 in which the lug 52 can move when it moves along the cam 510.

[0367] This light 560 includes a lateral bearing surface 561 against which the lug 52 comes to rest or near which the lug 52 comes when it passes beyond the projecting end 5101 of the cam 510 towards the hollow end 5102 under the effect of a rotation of the rotor R in the opposite direction to the direction of work, as will be explained in more detail later.

[0368] When the fourth pinion 14 is in the engaged position, the lug 52 is located on the axis of the housing 5104 of the cam 510 between the lateral bearing surface 561 of the slot 560 and the junction surface 5103 between the protruding end 5101 of the cam 510 and the recessed end 5102 of the cam 510, while being away from the housing 5104 (position A). The sliding shaft 42 is thus prevented from rotating.

[0369] When the fourth pinion 14 is in the immobilized position, the lug 52 is in the housing 5104 of the cam 510. 6.2.2. Operation

[0370] This type of drill can also be used to make holes with or without countersinking at the hole entry. i. Drill stopped before starting

[0371] Before starting the drill to perform a drilling operation, the drill is, where appropriate, fixed on a drilling grid, in a centering hole located in the axis of the hole to be drilled.

[0372] As long as the start button is not activated by the operator, the spindle 10 is fully retracted so that the first end stop of retraction 19 is in contact with the second pinion 12 which constitutes the second end stop of retraction.

[0373] The fourth pinion 14 is in its engaged position in which it is held in position as long as the bistable washer 70 is in its engaged state.

[0374] The lug 52 is located in the axis of the housing 5104 of the hollow end 5102 of the cam 510, and is away from it, between the lateral bearing surface 561 of the slot 560 and the junction surface 5103 between the protruding end 5101 of the cam 510 and the hollow end 5102 of the cam 510 (position A). ii. Drilling operation ii.l. Deployment of the spindle

[0375] To start the drill, an operator activates the start button to initiate a drilling operation.

[0376] The motor starts so that the rotor R is driven in rotation in the working direction, i.e. drilling direction.

[0377] The conical couple 15 is driven in rotation by the rotor R and drives in rotation the third pinion 13.

[0378] The fourth pinion 14, which is rotationally linked with the third pinion 13, is driven in rotation.

[0379] The first pinion 11 is driven in rotation by the third pinion 13 so that the spindle 10 is driven in rotation about its longitudinal axis.

[0380] The second pinion 12 is driven in rotation by the fourth pinion 14.

[0381] The reduction ratio between the first 11 and the third pinion 12 is different of the reduction ratio between the second pinion 12 and the fourth pinion 14. Thus, taking into account the helical connection between the second pinion 12 and the spindle 10, the spindle 10 is driven in translation along its axis and deploys out of the housing 20 until the first end-of-deployment stop 18 is in contact with the first pinion 11 which constitutes the second end-of-deployment stop.

[0382] During this period, the drill is driven along a helical trajectory with an adequate cutting speed and feed rate, thus achieving the expected drilling.

[0383] ii.2. End of spindle deployment: passage of the fourth pinion into position immobilized

[0384] When the first deployment end stop 18 is against the second deployment end stop 11, the deployment of the spindle 10 is stopped. The third 13 and fourth 14 gears therefore tend to rotate at different speeds. Thus, given the ogive shape of the pins 140 of the fourth gear 14, these pins 140 tend to come out of the clutch housings 130 of the third gear 13, so that the fourth gear 14 moves away from the third gear 13 towards its stationary position.

[0385] The second articulation points 701 of the bistable washer 70 with the sliding shaft 42 extend beyond the median plane PM so that the bistable washer 70 participates in moving the fourth pinion 14 into its immobilized position and then in maintaining it in its immobilized state.

[0386] During the movement of the fourth pinion 14 from its engaged position to its immobilized position, the lug 52 moves in translation along the axis of the sliding shaft 42 until it comes to rest in the housing 5104 of the cam 510 and is guided there if necessary by the ramp 5105 (position B).

[0387] In addition to or as an alternative to the ogive pins 140, the lever could allow the passage of the fourth pinion 14 into its immobilized position and the passage of the bistable washer 70 into its immobilized state. ii.3. Pin retraction

[0388] When the fourth pinion 14 is in its immobilized position, the fourth pinion 14 is immobilized in rotation and the second pinion 12 is also immobilized in rotation.

[0389] Thus, the spindle 10, which continues to be driven in rotation by the third pinion 13 and the first pinion 11, moves in translation along its axis in the direction of a retraction inside the housing 20.

[0390] ii.4. End of spindle retraction: passage of the fourth pinion into position engaged

[0391] The retraction of the spindle 10 takes place until the first end-of-retraction stop 19 comes into contact with the second pinion 12, which constitutes the second end-of-retraction stop.

[0392] The control means detect that the pin 10 is thus completely retracted, for example by following the evolution over time of the motor current.

[0393] When the control means detect that the spindle 10 is fully retracted, they drive the motor so that the rotor R rotates in the opposite direction to the working direction.

[0394] The sliding shaft 42 is then driven in rotation by the third pinion 13 and by the unidirectional clutch 43.

[0395] The lug 52 is then driven in rotation by the sliding shaft 42. It comes out of the housing 5104 of the cam 510 and then slides against the ramp 5100 of the cam from the hollow end 5102 to the protruding end 5101. The movement of the lug 52 along the ramp 5100 of the cam 510 induces a sliding of the sliding shaft 42 and of the fourth pinion 14 towards the engaged position.

[0396] During this movement, the second articulation points 701 of the bistable washer 70 to the sliding shaft 42 pass the median plane PM beyond which the bistable washer 70 exerts on the sliding shaft 42 a force tending to move it, and the fourth pinion 14, towards the engaged position.

[0397] If the pins 140 of the fourth pinion 14 extend into the clutch housings 130 of the third pinion 13, then the fourth pinion 14 moves into its engaged position. The fourth pinion 14 is then held in this engaged position by the bistable washer 70. The fourth pinion 14 is in its engaged position slightly before the lug 52 passes beyond the projecting end 5101 of the cam 510. Thus, at the end of the movement of the fourth pinion 14 towards its engaged position, the lug 52 passes beyond the projecting end 5101 of the cam 510, then moves slightly towards the housing 5104 of the cam 512 under the effect of the release of the spring 520, so that it is in the axis, i.e.in the extension of the housing 5104 of the cam 510 between the bearing surface 561 of the slot 560 and the connecting surface 5103 between the protruding end 5101 and the recessed end 5102 of the cam 510, while remaining away from the housing 5104 of the cam (position A). The lug 52 is thus blocked from rotation between these two surfaces 5103, 561 so that the sliding shaft 42 is immobilized from rotation.

[0398] If the pins 140 of the fourth pinion 14 do not extend into the clutch housings 130 of the third pinion 13, then the pins 140 come to rest against the third pinion 13 outside the clutch housings 130 and the lug 52 compresses the spring 520 in the housing 521 of the sliding shaft 42. The probability of this situation occurring is very low given the implementation of the "bean-shaped" clutch housings 130 which maximizes the chances that the pins 140 are always opposite the corresponding clutch housings 130.

[0399] Meanwhile, the third pinion 13 continues its rotation, the fourth pinion 14 is driven at a different frequency than the third 13 due to the difference The number of teeth between the first 11 and second 12 pinions is such that the pins 140 gradually synchronize with the clutch housings 130 of the third pinion 13. When the pins 140 are synchronized with the clutch housings 130, i.e., they are aligned, the spring 520 relaxes and acts on the bistable washer 70 in such a way that its second points of articulation 701 with the sliding shaft 42 extend beyond the median plane PM. The bistable washer gradually reaches its engaged position by pushing the sliding shaft 42, which completes its movement until the fourth pinion 14 is in its engaged position. The fourth pinion is then held in its engaged position by the bistable washer 70. The fourth pinion 14 is in its engaged position a little before the lug 52 passes beyond the protruding end 5101 of the cam 510.Thus, at the end of the movement of the fourth pinion 14 towards its engaged position, the lug 52 passes beyond the protruding end 5101 of the cam 510 and then moves slightly towards the cam 512 under the effect of the release of the spring 520, so that it is located on the axis of the housing 5104 of the cam 510 between the bearing surface 561 of the slot 560 and the connecting surface 5103 between the protruding end 5101 and the recessed end 5102 of the cam 510, while remaining away from the housing 5104 of the cam 510 (position A). The lug 52 is thus prevented from rotating between these two surfaces 561, 5103 and the sliding shaft 42 is prevented from rotating.

[0400] The bistable washer 70 is in its immobilized state.

[0401] The retraction can be stopped after a predetermined angle of rotation of the lug relative to the cam. This angle can be measured by the motor's angle sensor, taking into account the reduction ratio between the motor and the sliding shaft, and is considered by the drill's control means. In the illustrated embodiment, the cam is actually a double cam with two ramps, each extending through 180°, and the lug is a double lug, each end of which acts on a different cam. Therefore, half a turn of the double lug relative to the cam may be sufficient to move the fourth pinion from its stationary position to its engaged position. However, a full turn may be required depending on the reliability of the reset.

[0402] The drill is then in the state it was in before it was started so that a new drilling cycle can be started by pressing the start button. 6.2.3. Variant#: fork

[0403] In an alternative, not covered by the set of claims, the means for moving the fourth pinion 14 from its immobilized position to its engaged position do not include the cam system described above.

[0404] Alternatively, they include a 60 range.

[0405] Reference is made below to Figures 5 and 6, which illustrate the fork system in the context of the magnet embodiment, insofar as the fork system can be implemented in the same way in the bistable washer embodiment.

[0406] This fork 60 is traversed at one of its ends by the spindle 10. At the other of its ends, the fork 60 is linked in translation to the sliding shaft 42. The fork 60 is also traversed by a rotational stop shaft 67.

[0407] The fork 60 is movable in translation between:

[0408] - an engaged position, illustrated in [Fig. 5], in which the fourth pinion 14 is in the engaged position, and

[0409] - a stationary position, illustrated in [Fig. 6], in which the fourth pinion 14 is in its immobilized position.

[0410] The device includes a lock 62. This lock 62 includes at one of its ends a hook 620 and at the other of its ends a cam 621.

[0411] The hook 620 is capable of cooperating with an attachment point 64 linked to the fork 60.

[0412] The lock 62 is mounted to rotate freely about an axis 63 connected to the housing between:

[0413] - a release position, illustrated in [Fig. 5], in which the hook 620 does not does not cooperate with the attachment point 64, so it does not hold the fork 60 in its immobilized position, and

[0414] - a locking position, illustrated in [Fig. 6], in which the hook 620 cooperates with the hook point 64 so that it keeps the fork 60 in its immobilized position.

[0415] The fork 60 carries a spring blade 65, which tends to keep the lock 62 in its locked position.

[0416] A compression spring 66 is interposed between the first end stop of retraction 19 and the fork 60.

[0417] The first end stop of retraction 19 includes a conical portion 190 oriented towards the side of the lock 62.

[0418] The hook 620 includes a ramp 6200 intended to act on the hooking point 64.

[0419] Throughout the deployment of the spindle 10 out of the housing 20, the fourth pinion 14 is held in its engaged position by the bistable washer 70, which is in its engaged state. The fork 60 is in its engaged position, in which it is held by the bistable washer 70, and in which the hook 620 does not cooperate with the engagement point 64, which is bearing against the ramp 6200.

[0420] During the movement of the fourth pinion 14 from its engaged position to its immobilized position under the effect on the one hand of a relative rotation of the third 13 and fourth 14 pinions and on the other hand of the passage of the bistable washer 70 from its engaged state to its immobilized state, the fork 60 is progressively driven in translation by the sliding shaft 42 towards the first end stop of retraction 19. During this movement, the hook point 64 slides against the ramp 6200 of the lock 62, which induces a rotation of the lock 62 around the axis 63 allowing the progressive passage of the hook point 64 in the hook 620.

[0421] When the fourth pinion 14 is in its immobilized position, in which it is held by the bistable washer 70, the fork 60 is in its immobilized position and the lock 62 is in its locked position in which it is held by the spring blade 65. The hook point 64 is then trapped in the hook 620 so that the fork 60 is held in its immobilized position.

[0422] Given that the fourth pinion 14 is in its immobilized position, the spindle 10 retracts.

[0423] On a final portion of the retraction stroke of the spindle 10, the first end stop of retraction compresses the spring 66, then the conical portion 190 of the first end stop of retraction 19 acts progressively on the cam 621 of the lock 62 so that the lock 62 rotates around the axis 63. This rotation of the lock 62 induces a progressive displacement of the lock 62 from its locking position to its release position. When the lock 62 reaches its release position, the hook 620 releases the hook point 64 so that the fork 60 is driven in translation along the spindle 10 under the effect of the release of the compression spring 66. The fork 60 then drives the sliding shaft 42 in translation by exerting a displacement force on it causing the second articulation points 701 of the bistable washer 70 with the sliding shaft 42 to pass the median plane PM.The bistable washer 70 thus gradually moves from its immobilized state to its engaged state, and the fourth pinion 14 gradually moves from its immobilized position to its engaged position.

[0424] If, during the movement of the fourth pinion 14 from its stationary position to its engaged position, the pins 140 of the fourth pinion 14 extend into the clutch housings 130 of the third pinion 13, then the fork 60, under the effect of the release of the spring 66, and the bistable washer 70 move the sliding shaft 42 and the fourth pinion 14 into its engaged position. The fourth pinion 14 is then held in this engaged position by the bistable washer 70.

[0425] If, during the movement of the fourth pinion 14 from its immobilized position to its engaged position, the pins 140 of the fourth pinion 14 do not extend into the clutch housings 130 of the third pinion 13, then the pins 140 come to rest against the third pinion 13 outside the clutch housings 130 and the spring 66 partially relaxes and exerts a force on the fork 60 and on the sliding shaft 42 tending to press the end of the pins 140 against the third pinion 13. The lock 60 is then in its release position in which the hooking point 64 is not trapped in the hook 620.Then, as in the case of the cam system, when the pins 140 synchronize with the clutch housings 130, the spring 66 continues to unwind, causing the fork 60 to translate towards and the sliding shaft 42 towards their engaged positions, so that the second articulation points 701 of the bistable washer 70 with the sliding shaft 42 gradually pass the median plane PM. The bistable washer 70 then pushes the sliding shaft until the fourth pin 14 is placed in its engaged position, in which it is held by the bistable washer 70.

[0426] In this variant, no second retraction end stop is implemented. The retraction end position of the spindle 10 corresponds to its position when the fourth pinion 14 leaves its immobilized position. 6.3. Variants

[0427] The two embodiments described above, as well as their variants, are wholly or partially combinable with each other. Thus, variants of the magnetic embodiment can be implemented in the bistable washer embodiment, and vice versa.

Claims

1. Demands Drilling device comprising a housing containing: - a motor comprising a rotor capable of rotating in a working direction; - a transmission; - a drilling spindle capable of being driven in rotation or in rotation and translation along a longitudinal axis of said spindle via said motor and said transmission; said transmission comprising: - a first pinion linked in rotation with said spindle and mounted movable in translation along said spindle along said longitudinal axis of said spindle; - a second pinion linked to said spindle by a helical connection along said longitudinal axis of said spindle; - a third pinion, meshing with said first pinion, guided in rotation relative to said casing and capable of being driven in rotation by said motor; - a fourth pinion, guided in rotation and translation relative to said housing, meshing with said second pinion, said fourth pinion being movable between: - an engaged position in which it is linked in rotation with said third pinion by first means of connection, the rotational drive of said third pinion by said motor in said working direction inducing a deployment of said spindle over a predetermined deployment stroke; - a stationary position in which it is rotationally connected to said housing by second connecting means and is free to rotate with respect to said third pinion, a rotation of said third pinion by said motor in said working direction inducing a retraction of said spindle following a predetermined retraction stroke, characterized in that said device comprises first means for moving said fourth pinion from said stationary position to said engaged position, said first means of movement comprising: - means for reversing the direction of rotation of said rotor capable of rotating said rotor in the opposite direction to said working direction; - a sliding shaft carrying said fourth pinion and linked in translation to said fourth pinion along its axis of rotation; - a unidirectional clutch configured to: - not link said third pinion and said sliding shaft in rotation when said rotor rotates in said working direction, and - link said third pinion and said sliding shaft in rotation when said rotor rotates in said opposite direction to said working direction;- a cam shaped to induce, during a rotation of said rotor in said direction opposite to said working direction, a displacement of said sliding shaft and of said fourth pinion from said immobilized position to said engaged position, said cam being annular and coaxial with said sliding shaft, said cam having a ramp whose development is parallel to the axis of rotation of said sliding shaft, said ramp being in contact with a lug fixed in rotation to said sliding shaft along the axis of rotation of said sliding shaft and at least partially fixed in translation to said sliding shaft along the axis of rotation of said sliding shaft.;

2. Device according to claim 1 in which said first means of movement comprise a coaxial ring said sliding shaft and movable in translation along the axis of rotation of said sliding shaft relative to said sliding shaft, said lug being linked in translation and in rotation to said ring, linked in rotation to said sliding shaft, and movable in translation relative to said sliding shaft along said axis of rotation, an elastic element being disposed between said ring and a shoulder carried by said sliding shaft.

3. A device according to claim 1, comprising means for maintaining said fourth pinion in its engaged position and in its immobilized position, and second means for moving said fourth pinion from its engaged position to its immobilized position immobilized, and conversely, said holding means and said second means of movement comprising a bistable elastic element capable of taking two stable states, namely: - a clutch state in which it maintains said fourth pinion in its engaged position, and - an immobilization state in which it maintains said fourth pinion in its immobilized position.

4. Device according to claim 3 comprising a sliding shaft carrying said fourth pinion and linked in translation to said fourth pinion about its axis of rotation, said bistable elastic element comprising at least one longitudinal element having two ends, one of said ends being articulated at at least a first articulation point on said housing and the other of said ends being articulated at at least a second articulation point on said sliding shaft, said at least one longitudinal element being compressible in a direction collinear with a line passing through said two ends and having a predetermined stiffness, said sliding shaft being movable relative to said housing between positions corresponding to said engaged and immobilized positions of said fourth pinion, said second articulation point of said sliding shaft occupying, in said engaged and immobilized states,positions substantially symmetrical with respect to a median plane perpendicular to said sliding shaft and passing through said first articulation point of said housing, the distance between said ends of said at least one longitudinal element in a relaxed state being greater than the distance between said first and second articulation points when said second articulation point of said sliding shaft is in said median plane.

5. Device according to claim 4 in which said at least one elongated element belongs to the group comprising: - a metal blade whose compressibility results from its buckling; - a component integrating a spring whose compressibility results from the compression of said spring.

6. Device according to claim 4 or 5 in which said bistable elastic element comprises a bistable elastic washer.

7. A device according to any one of claims 4 to 6 comprising second means for moving said fourth pinion from said engaged position to said immobilized position, said second means for moving comprising: - a first end-of-deployment stop integral with said spindle and intended to bear against a second end-of-deployment stop connected to said housing, said first and second end-of-deployment stops defining the end of said deployment stroke of said spindle, - said first connecting means comprising pins integral with said fourth pinion and extending along its axis of rotation, said pins being able to cooperate with clutch housings provided for this purpose in said third pinion in said engaged position to link said third and fourth pinions in rotation,said pins and clutch housings being configured to induce a displacement of said fourth pinion in the direction of said immobilized position when said first end-of-deployment stop is abutted against said second end-of-deployment stop and said rotor rotates in said working direction, said displacement occurring over a stroke inducing said second articulation point of said sliding shaft to pass through said median plane and the passage of said bistable elastic element into said immobilized state.

8. A device according to any one of claims 4 to 6 comprising second means for moving said fourth pinion from said engaged position to said immobilized position, said second means comprising an actuator capable of transmitting said fourth pinion a displacement force capable of causing said second articulation point of said sliding shaft to pass said median plane and to move said bistable elastic element from said engaged state to said immobilized state, said actuator being able to assume at least: - a neutral state in which it does not transmit said displacement force to said fourth pinion, said neutral state being maintained when said spindle is moved over said predetermined extension stroke and over said predetermined retraction stroke, and - a displacement state in which it transmits said displacement force to said fourth pinion, said displacement state being taken, at the end of a deployment of said spindle over the entire of said predetermined deployment stroke, under the effect of a rotation of said rotor in said working direction.

9. Device according to claim 8, wherein said actuator comprises a movable lever capable of assuming: - said neutral state in which said spindle does not transmit any force to said lever and said lever does not transmit said displacement force to said fourth pinion, such that said fourth pinion is held in said engaged position by said bistable elastic element in the engaged state, said neutral state being maintained when said spindle is moved over said predetermined extension stroke and over said predetermined retraction stroke; - said displacement state, assumed after deployment of said spindle over the entirety of said predetermined extension stroke, under the effect of a rotation of said rotor in said working direction,in which said lever transmits said displacement force to said fourth pinion so as to bring said second articulation point of said sliding shaft beyond said median plane and to move said bistable elastic element from said engaged state to said immobilized state, said device comprising a first end-of-deployment stop integral with said spindle and intended to bear against a second end-of-deployment stop linked to said housing, said first and second end-of-deployment stops delimiting the end of said deployment stroke of said spindle, said device comprising a second elastic return element against the effect of which said first pinion is mounted to move in translation along said spindle when, a rotation of said spindle in said working direction, when said first end-of-deployment stop is in contact with said second end-of-deployment stop, inducing a translational drive,along said spindle, from said first pinion by said second pinion, said first pinion acting on said lever to place it in its moving position.

10. A device according to claim 1 or 2, comprising: - means for retaining said fourth pinion in its engaged position, said means for retaining said fourth pinion in its engaged position comprising a magnetic attraction element acting on said fourth pinion when it is in said engaged position, a force maintaining it in said engaged position, and - second means of displacement of said fourth pinion from its engaged position to its immobilized position, said second means of displacement comprising a first elastic return element exerting on said fourth pinion a force tending to move it from its engaged position to its immobilized position, and when it is in said immobilized position, a force maintaining it in said immobilized position.

11. Device according to claim 10 wherein said magnetic attraction element is a permanent magnet.

12. Device according to claim 11 wherein said permanent magnet is an electromagnet.

13. Device according to any one of claims 10 to 12 comprising means for deactivating the holding effect of said holding means of said fourth pinion in said engaged position.

14. Device according to claims 12 and 13 wherein said deactivation means comprise means for supplying electricity to said electromagnet so as to cancel the magnetic attraction it generates.

15. A device according to claim 13 or 14 wherein said means for deactivating the holding effect of said holding means of said fourth pinion in said engaged position comprise an actuator capable of transmitting said fourth pinion a repulsive force greater than the magnetic attraction force transmitted to said fourth pinion by said magnetic attraction element, said actuator being able to assume at least: - a neutral state in which it does not transmit said repulsive force to said fourth pinion, said neutral state being maintained when said spindle is moved over said predetermined extension stroke and over said predetermined retraction stroke, and - a repulsive state in which it transmits said repulsive force to said fourth pinion, said repulsive state being assumed,following the retraction of said spindle over the entire predetermined retraction stroke under the effect of a rotation of said rotor in said working direction.

16.

17. Device according to claim 15, wherein said actuator comprises a movable lever capable of taking: - said neutral state in which said spindle does not transmit force to said lever and said lever does not transmit said repulsive force to said fourth pinion so that said fourth pinion is held in said engaged position by said magnetic attraction element, said neutral state being maintained when said spindle is moved on said predetermined deployment stroke and on said predetermined retraction stroke; - said state of repulsion, taken at the end of a deployment of said spindle over the entirety of said predetermined deployment stroke, under the effect of a rotation of said rotor in said working direction, in which said lever transmits said repulsion force to said fourth pinion so as to counter the magnetic attraction force transmitted by said magnetic attraction element to said fourth pinion, said device comprising a first deployment end stop integral with said spindle and intended to bear against a second deployment end stop linked to said housing, said first and second deployment end stops delimiting the end of said deployment stroke of said spindle, said device comprising a second elastic return element against the effect of which said first pinion is mounted movable in translation along said spindle, a rotation of said spindle, in said working direction, when said first deployment end stop is in contact with said second deployment end stop, inducing a translational drive, along said spindle, of said first pinion by said second pinion, said first pinion acting on said lever to place it in its repulsive state.Device according to any one of claims 1 to 16 in which said ramp of said annular cam comprises a projecting end in the direction of the engaged position of said fourth pinion and a recessed end receiving said pin when said fourth pinion is in the immobilized position, said device comprising means for immobilizing in rotation said sliding shaft when said fourth pinion is in the engaged position such as the trajectory of said lug during the passage of the fourth pinion. Its engaged position and its immobilized position are parallel to the axis of said sliding shaft.

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