Patent Description:
Drills for drilling rails are known, having a body which supports an electric or internal combustion motor, a drilling tool, a reduction gear arranged between the motor and the drilling tool, and means for removably fixing the body with respect to an element to be drilled, wherein means are provided for translating the drilling tool with respect to the element itself.

The drills for drilling rails of the prior art still have some drawbacks.

A problem which is not adequately solved is the difficulty of making holes in bad weather or bad environmental conditions, in which water, sand, soil particles or snow either fall or are carried into the zone of the drill, where they are aspirated by the cooling system of the drill or penetrate into the connections and the electric circuits, with the risk of damaging the drill and injuring the operator. The most typical prohibitive weather or environmental conditions include rain, storms, wind in presence of dust, sand and water.

At the current state, in case of prohibitive weather conditions, the rail drilling works must be interrupted and the drills must be put away, sheltered from the rain and the wind until the weather improves. This implies undesired waste of time and delays in the works. Alternatively, when possible, tents or temporary protective constructions can be erected which protect the construction site from the external conditions. This second solution is particularly useful in climatic zones which are hostile in all cases for the operators, e.g. in case of very cold or very hot temperatures, but is excessively costly for railway construction sites which move rapidly from one point of operation to another and are only occasionally subject to rain and storms.

lt is thus the object of the present invention to provide a protective sheath for a drill for drilling railway rails, as well as a drill provided with said sheath, having features such to allow safe operation of the drill also in bad weather conditions.

This and other objects are achieved by a protective sheath according to claim <NUM> and by the combination of a drill and a protective sheath according to claim <NUM>. The dependent claims relate to advantageous and preferred embodiments.

According to an aspect of the invention, a sheath for a drill is provided, of the type having:.

By virtue of the impermeability of the sheath and of the ventilation channel with air inlet openings facing downwards, the drill can be protected from bad weather conditions, in particular from the rain, without compromising the cooling of the electric motor. The elastomeric material of the sheath allows its easy application onto and, if necessary, removal from the drill.

According to an embodiment
at least one of the openings (<NUM>; <NUM>) or an additional opening formed in the sheath (<NUM>) is adapted for the replacement of at least one removable part (<NUM>), especially a rechargeable battery or an accessory, of the drill (<NUM>) without having to remove the sheath from the drill (<NUM>).

In order to understand the invention and better appreciate its advantages, the description of some embodiments will be provided below by way of non-limiting examples with reference to the accompanying figures, in which:.

For a better understanding of the conditions of use of the protective sheath, a drill <NUM> for drilling railway rails will be firstly described, with particular reference to the features of the drill <NUM> with which the protective sheath must interact, followed by the description of the protective sheath itself.

With reference to <FIG>, a drill <NUM> for drilling railway rails (not shown) comprises an electric motor <NUM>, which may be powered by a battery, a drilling tool <NUM> (shown here as a pilot drill bit, by way of example) defining a tool axis <NUM>, a reduction gear <NUM> arranged between the motor <NUM> and the drilling tool <NUM>, a replaceable and rechargeable battery <NUM> and a support portion <NUM>.

The support portion <NUM> may be substantially "L"-shaped with a first wing <NUM> which forms a connection portion <NUM>, to which the electric motor <NUM> is coupled, and a second wing <NUM> extending in transversal direction, e.g. approximately perpendicular, with respect to the first wing <NUM> and which supports the drilling tool <NUM>. The electric motor <NUM> is arranged above the second wing <NUM> and is vertically distanced from it, and the electric motor <NUM> and the second wing <NUM> both project from the first wing <NUM> in a same drilling direction <NUM> of the drill <NUM>, conferring a U-shape to the drill <NUM>.

The drill <NUM> may further comprise means <NUM> (shown with a dashed line in the figures) for removably fixing the drill <NUM>, in particular the support portion <NUM> with respect to an element (e.g. a rail) to drill.

In order to improve the visibility in the drilling region <NUM> (<FIG>), the drill <NUM> may comprise a lighting system having, for example, two lighting sources <NUM>, <NUM> (e.g. LEDs) mutually spaced apart and arranged on two opposite sides with respect to a hypothetical vertical working plane containing the tool axis <NUM>.

The drill <NUM> comprises means for switching on/manually controlling it, e.g. a button or a lever <NUM>, which may be arranged, for example, on an upper side of the drill <NUM>, e.g. in an upper wall of the electric motor <NUM>.

The drill <NUM> may comprise a display <NUM>, preferably multicolour, to generate one or more visual warnings, e.g. charge state of the battery <NUM>, anomaly during drilling, electric power supply error, need for maintenance, as well as instantaneous drilling conditions. The (multicolour) display <NUM> may be arranged on an upper-rear side (user side) of the drill <NUM>, preferably in an upper and/or rear wall of the electric motor <NUM>.

The drill <NUM> may comprise a speed switch <NUM>, with at least two or three stable switching positions, which makes it possible to select the rotation speed of the motor <NUM>, so as to be able to drill with bits of different diameters, but remaining in all cases within an optimal speed range of the teeth of the bit.

The drill <NUM> may also comprise a switch for activating and deactivating a lighting system of the drill.

The rechargeable battery <NUM> may be reversibly mechanically coupled to a battery interface <NUM> of the drill <NUM> formed in an upper portion of the electric motor <NUM> facing in drilling direction <NUM> (<FIG>) and possibly above the axis <NUM> of the tool <NUM>, e.g. centred with respect to the working plane. In this manner, the battery <NUM> forms the free end of the upper wing of the U shape of the structure of the drill <NUM>, approximates the centre of gravity of the drill <NUM> towards the rail, does not cast shadows in the lighting of the drilling region <NUM>, does not hinder the user who is on the opposite side with respect to the drilling region <NUM> and does not interfere with the ballast under the rail <NUM>.

The battery interface <NUM> and the battery <NUM> may be configured for a mechanical coupling and a electric connection by means of translational sliding of the battery <NUM> from the top downwards or parallel to the extension of the first wing <NUM> of the supporting portion <NUM>.

The drill <NUM> may comprise a further display <NUM> for viewing operating and/or control parameters of the drill <NUM>. The further display may be positioned in a side wall of the motor <NUM>.

The motor <NUM> comprises a cooling system with one or more air intake openings <NUM>, formed for example in a rear wall (user side) or in a rear-side wall of the motor <NUM>, as well as one or more air discharge openings <NUM>, formed for example in a front wall (tool side) or in a front-side wall of the motor <NUM> (<FIG>).

The drill <NUM> may further comprise a handle <NUM>, which can be either fixed or locked to the support portion <NUM> by means of a locking member <NUM>, e.g. a screw.

According to the invention, the drill <NUM> may be equipped with a sheath <NUM> made of flexible elastomeric material, impermeable to liquids, which has a generically tubular shape with a front opening <NUM> and a rear opening <NUM> opposite the front opening <NUM> in the direction of the tool axis <NUM>, so as to be able to be slotted (or inserted) over the electric motor <NUM> and over at least one part of the battery <NUM> to protect them.

The sheath <NUM> forms a ventilation channel <NUM> with one or more first inlet openings <NUM> formed in an outer surface of the sheath <NUM> and facing downwards, and with an inner ventilation section <NUM>, which is concave so as not to adhere to the motor <NUM>, open towards the inside of the sheath <NUM> so as to communicate cooling air from the inlet openings to a cooling system, in particular to the intake openings <NUM>, of the motor <NUM>. The internal ventilation section <NUM> is isolated from the outside by virtue of the wall of the sheath <NUM> in which it is formed.

By virtue of the impermeability of the sheath <NUM> and of the ventilation channel <NUM> with air inlet openings <NUM> facing downwards, the drill <NUM> can be protected from bad weather conditions, in particular from the rain, without however compromising the cooling of the electric motor. The elastomeric material of the sheath <NUM> allows its easy application onto and, if necessary, removal from the drill <NUM>.

ln an embodiment, the ventilation channel <NUM> is formed in a rear portion (user side) of the sheath <NUM>, at intake openings <NUM> of the motor <NUM> of the drill <NUM>.

The ventilation channel <NUM> may be arch- or horseshoe-shaped along two side walls and along an upper wall of the sheath <NUM> so as to be positioned (with the sheath applied on the drill) straddling the electric motor <NUM>. The air inlet openings <NUM> are advantageously formed at the two lower ends of the ventilation channel <NUM>.

The ventilation channel <NUM> may comprise one or more intake filters <NUM>, preferably positioned in replaceable manner at air inlet openings <NUM>. The intake filters <NUM> may comprise nets, fabrics, porous bodies, e.g. made of foam, with mesh or cell size selected according to the desired degree of protection. This further improves the protection from dust and particulate matter. Rain protection is guaranteed by the air intake on the bottom and from the bottom, obtained by positioning and orienting the air inlet openings <NUM>.

According to an embodiment, instead of or in addition to the aforesaid intake filters <NUM>, one or more labyrinth bodies <NUM>' may be envisaged, preferably positioned at the air inlet openings <NUM> and defining a tortuous passage path, such to cause the water drops and dust to be deposited and/or fall back outside before entering into the ventilation channel <NUM>. The labyrinth body <NUM>' may be made separately and then connected to the ventilation channel <NUM>. The labyrinth body <NUM>' may be made of material different from that of the ventilation channel <NUM>, e.g. of a material or of a combination of materials that are water-repellent and/or hydrophilic. The labyrinth body <NUM>' may be made removably accommodated in a specific housing formed in the ventilation channel <NUM>.

According to an embodiment, the sheath <NUM> forms a discharge channel <NUM> with one or more outlet openings <NUM> formed in an outer surface of the sheath <NUM> and facing downwards, and with an inner discharge section <NUM>, which is concave so as not to adhere to the motor <NUM>, and is open towards the inside of the sheath <NUM>, so as to be able to receive air expelled from the cooling system, in particular from the discharge openings <NUM>, of the motor <NUM> and to discharge it through the outlet openings <NUM>. The internal discharge section <NUM> is isolated from the outside by virtue of the wall of the sheath <NUM> in which it is formed.

Similarly to the ventilation channel <NUM>, the discharge channel <NUM> also protects the motor <NUM> of the drill <NUM> from the penetration of rain, dust and particles in case of bad environmental or weather conditions.

In an embodiment, the discharge channel <NUM> is formed in a front portion (tool side) and/or side portion of the sheath <NUM>, at discharge openings <NUM> of the motor <NUM> of the drill <NUM>.

Preferably, the inner discharge section <NUM> comprises two opposite lateral cavities, formed in two lateral walls of the sheath <NUM> and in communication with the at least one outlet opening <NUM> formed in a bottom wall of the sheath <NUM> and facing downwards.

The discharge channel <NUM> may comprise one or more filters <NUM>, preferably positioned in replaceable manner at air outlet openings <NUM>. This further improves the degree of protection from dust and particulate matter. Rain protection is guaranteed by the downward positioning and orientation of the outlet openings <NUM>. A same labyrinth body <NUM>' as described in connection with the inlet openings may be provided instead of or in addition to the filter <NUM>.

The ventilation channels <NUM> and discharge channels <NUM> are preferably spaced apart so as to either prevent or hinder the suction of air from the discharge channel <NUM> into the ventilation channel <NUM>.

The protective sheath <NUM> may form a fixing hole <NUM> for reversibly fixing its correct position on the drill <NUM> by means of a locking member <NUM>, e.g. by means of a same locking member of the handle <NUM> of the drill <NUM>.

In an embodiment, the fixing hole <NUM> is formed in a rear (user side) - upper region of the sheath <NUM>, which is superimposed on a rear (user side) region of the drill <NUM>.

The sheath <NUM> forms a battery opening <NUM>, which can be positioned at the battery <NUM> of the drill <NUM> and delimited by a battery-covering edge <NUM>, which is flexible and can be elastically widened so as to:.

In order to increase adherence of the sheath <NUM> to the battery <NUM>, the battery-covering edge <NUM> may be reinforced by means of a reinforcement edge or rib <NUM> (diagrammatically shown with a dashed line in <FIG>), extending along the battery-covering edge <NUM> and of greater thickness than the wall of the sheath <NUM> adjacent to the battery-covering edge <NUM>. The reinforcement rib <NUM> may project towards the internal of the sheath <NUM> (in direction of the drill) to form a sealing lip which improves sealing with the battery <NUM>.

Advantageously, the battery opening <NUM> is formed by the front opening <NUM> (<FIG>) or, alternatively, by the rear opening <NUM>.

Furthermore, the battery-covering edge <NUM> may form a handle portion <NUM> projecting towards the outside of the sheath <NUM> to facilitate the manual gripping and widening of the battery opening <NUM>. For better ergonomics, the handle portion <NUM> is formed on an upper side of the battery-covering edge <NUM>.

In an embodiment, the sheath <NUM> forms a first portion <NUM> projecting outwards, in a bellows, stepped or thinned wall fashion, positioned at the button/lever <NUM> for switching the drill <NUM> on and off, e.g. on an upper side of the sheath <NUM>, and deformable so as to allow the actuation of the button/lever <NUM> for switching on and off from outside of the sheath <NUM>.

The sheath may also form a first viewing zone <NUM> made of transparent material and which does not substantially alter the visibility of colours, wherein the first viewing zone <NUM> may be positioned at the (multicolour) display <NUM> and formed, e.g. on an upper-rear side (user side) of the sheath <NUM>. The first viewing zone <NUM> may be externally polished and/or thinned (to further increase transparency) with respect to the surrounding walls of the sheath <NUM>.

The sheath <NUM> may form a second portion <NUM> projecting outwards, in a bellows, stepped or thinned wall fashion, positioned at the speed switch <NUM> of the drill <NUM>, e.g. in a side wall of the sheath <NUM>, and deformable so as to allow the manual switching of the speed switch <NUM> from outside of the sheath <NUM>.

In an embodiment, the sheath <NUM> further forms one or more lighting portions <NUM> made of transparent material, which may be externally polished and/or thinned (to further increase transparency) with respect to the surrounding walls of the sheath <NUM>. The one or more lighting portions <NUM> may be positioned at one or more light sources <NUM>, <NUM> of the lighting system of the drill <NUM>. Preferably (<FIG>), there are provided two different lighting portions <NUM> mutually spaced apart and arranged on two opposite sides with respect to a hypothetical vertical median plane of the sheath <NUM> and facing in front direction or in front-lower direction (<FIG>, <FIG>) towards the drilling region of the drill <NUM>.

The sheath <NUM> may form a second viewing zone <NUM> made of transparent material, e.g. in a lateral wall of the sheath <NUM>, which can be positioned at the further display <NUM> of the drill <NUM>. The second viewing zone <NUM> may be externally polished and/or thinned (to further increase transparency) with respect to the surrounding walls of the sheath <NUM>.

The sheath <NUM> may form a third portion <NUM> projecting towards the outside, in a bellows, stepped or thinned wall fashion, which can be positioned at an on/off switch of the lighting system of the drill <NUM>, e.g. in a lateral wall of the sheath <NUM>, and deformable so as to allow the actuation of the button from the outside of the sheath <NUM>.

According to the presence of a single or both the second <NUM> or third <NUM> bellows-like portion, such second <NUM> or third <NUM> bellows-like portion may be formed in the region indicated for the sake of simplicity by means of both reference numbers <NUM> and <NUM> or, if both second <NUM> or third <NUM> bellows-like portions are envisaged, they may be formed in mutually distanced regions of the sheath <NUM>.

Advantageously, the portions <NUM>, <NUM>, <NUM>, <NUM> of the sheath <NUM> which cover switching members (e.g. one or more on, off, speed switch, lighting, programming and viewing buttons) of the drill <NUM>, are defined and visibly highlighted by a step-like or grooved contour.

Similarly, also the transparent viewing zones <NUM>, <NUM> of the sheath <NUM> may be defined and visibly highlighted by means of a step-like or grooved contour.

This makes it possible to immediately recognise all the use interfaces of the drill <NUM> covered by the sheath <NUM> and facilitate its use.

In a preferred embodiment, the protective sheath covers the motor <NUM> and at least one part of the battery <NUM> of the drill <NUM>, so that a handle <NUM> for transporting the drill <NUM>, a tool advancement lever <NUM>, the fixing means <NUM> (if envisaged), and the portion or wing <NUM> which supports the drilling tool <NUM> extend outside the sheath <NUM>.

In the "U"-shaped drill configuration described above, the sheath <NUM> is applied only onto the upper wing of the structure of the drill <NUM>.

The sheath <NUM> is advantageously formed in one piece of elastomeric material, e.g. silicon, for example made by injection moulding.

The sheath <NUM> makes it possible to confer an IP33, IP <NUM> or higher degree of protection (as defined in standard EN <NUM> (CEI <NUM>-<NUM>)) to the drill <NUM>.

Claim 1:
Protective sheath (<NUM>) applicable to a drill (<NUM>) for drilling rails of the type having:
- a support portion (<NUM>) that supports an electric motor (<NUM>) that can be powered by a battery (<NUM>), a drilling tool (<NUM>) defining a tool axis (<NUM>), and a reduction gear (<NUM>) arranged between the motor (<NUM>) and the drilling tool (<NUM>),
- a rechargeable battery (<NUM>) removably coupled with the electric motor (<NUM>),
wherein said sheath (<NUM>) is made of elastomeric flexible material, impermeable to liquids, and has a generically tubular shape with a front opening (<NUM>) and a rear opening (<NUM>) opposite the front opening (<NUM>) in the direction of the tool axis (<NUM>), so as to be able to be slotted over the electric motor (<NUM>) and over at least a part of the battery (<NUM>) to protect them,
wherein the sheath (<NUM>) forms a ventilation channel (<NUM>) with two first inlet openings (<NUM>) formed in an outer surface of the sheath (<NUM>) and facing downwards, and with an inner ventilation section (<NUM>) that is concave and open towards the inside of the sheath (<NUM>) so as to communicate cooling air from the inlet opening (<NUM>) to a cooling system of the drill (<NUM>), characterized in that the ventilation channel (<NUM>) is shaped like an arc extending along two lateral walls and along an upper wall of the sheath (<NUM>) so as to be positioned, when the sheath is applied on the drill, astride of the electric motor (<NUM>), and wherein the air inlet openings (<NUM>) are formed at the two lower ends of the ventilation channel (<NUM>).