Patent Description:
Several different embodiments of arrangements for bringing a clamping element fastened to a railroad sleeper and forming part of a clamping unit to a position in which it fastens said rail section to said sleeper are known in the art.

Example of conventional such arrangements are found in <CIT>, <CIT> and <CIT>.

These arrangements include large structures carried by wheel equipped wagons intended to be moved along a rail track. As is evident such an arrangement is heavy, and it is therefore a need for lifting machines to move it onto and away from a rail track.

Also, smaller arrangements are known for bringing a clamping element fastened to a railroad sleeper, e.g. <CIT> and <CIT>, but also these known arrangements are relatively heavy and will therefore need some kind of lifting aid for movement thereof.

The object of the present invention is to provide a solution to the issues mentioned above by providing an improved rail clamp handling arrangement, as well as an improved method for handling clamps.

The object according to the invention is achieved by a rail clamp handling arrangement according to claim <NUM>.

Thanks to the invention a rail clamp handling arrangement is provided that is substantially lighter than prior art machines, enabling a single person to carry the machine. Further, the invention in the basic principle may completely utilize mechanical drive, which provides an environmental advantage compared to prior art machines that conventionally use hydraulics.

Further beneficial aspects of the invention are apparent from the description and also from what is defined in the dependent claims.

The invention will be described in more detail in the following with reference to the accompanying drawings, which for the purpose of exemplification illustrate a schematic embodiment of the invention and some basic details of the power and transmission arrangement.

The invention provides a rail clamp handling arrangement <NUM> of a lightweight kind that may be lifted and moved by one person, possibly without use of any lifting aid.

In <FIG> there are shown schematic views of a rail clamp handling arrangement <NUM> according to the invention. There is shown a rail <NUM> that is attached to the ground in a traditional way by means of clamping elements <NUM>.

The rail clamp handling arrangement <NUM> comprises a support structure <NUM>, <NUM>, <NUM>, preferably covered by a housing <NUM>. The support structure <NUM>, <NUM>, <NUM> includes a lower part <NUM> and an upper part <NUM> horizontally extending in a transvers direction in relation to the extension of the rail <NUM>. Further, the support structure includes a fixed support wall <NUM> (schematically shown in <FIG>) attached to the upper part <NUM> and horizontally extending in a transverse direction in relation to the upper part <NUM>. A motor <NUM> and a first part <NUM> of a transmission is attached to the support wall <NUM>. The first part <NUM> of the transmission has an output shaft <NUM> that drives a chain <NUM> (or belt, see <FIG>).

The lower part <NUM> of the support structure extends symmetrically in the transversal direction in relation to the fixed support wall <NUM> and the longitudinal extension of the rail <NUM>, i.e. mirror symmetrically in relation to a central plane C. The lower part <NUM> of the support structure, at each outer end portion <NUM> is arranged with connection means (e.g. through holes provided with shafts) that provide pivot points <NUM> for first lever arms <NUM>, that are arranged mirror symmetrically. The pivot points <NUM> are arranged at an intermediate position of each first lever arm <NUM>. Further the lower part <NUM> of the support structure, at a position inside of the outer portion <NUM> is arranged with connection means (e.g. through holes provided with shafts) that provide pivot points <NUM> for second lever arms <NUM>, that are also arranged mirror symmetrically. The pivot points <NUM> are arranged at an intermediate position of each second lever arm <NUM>.

The power and transmission means <NUM>, <NUM> rotatably drives a threaded shaft <NUM> included in the invention. The threaded shaft <NUM> is rotated by means of a drive sleeve <NUM>, that has a fixed central position in relation to the support structure <NUM>, <NUM>, e.g. within the housing <NUM>, by means of bearings (not shown). The shaft <NUM> is positioned such that the driving sleeve <NUM> is at the centre of the extension of the drive shaft <NUM>. A substantial portion of each threaded shaft <NUM> will protrude on each side of an upper part of the housing <NUM>.

At each outer portion of the threaded shaft <NUM> there are positioned first displacing nuts <NUM> which also interfit with the threaded shaft <NUM>. The displacing nuts <NUM> are attached to one first lever arm <NUM> each, by means of an upper pivotal connection <NUM> arranged adjacent the upper end of an upper part <NUM> of each lever arm <NUM>.

At the other end of the first lever arm <NUM>, adjacent a lower end of a lower part <NUM> of the first lever arm <NUM>, there is arranged a contact member <NUM> for active contact with a clamping element <NUM>.

Further at intermediate positions, between the sleeve <NUM> and the first displacing nuts <NUM>, there are positioned second displacing nuts <NUM> which also interfit with the threaded shaft <NUM>. The second displacing nuts <NUM> are attached to an upper part <NUM> of each second lever arm <NUM> each, by means of an upper second pivotal connection <NUM> arranged adjacent the upper end of the upper part <NUM> of each second lever arm <NUM>.

At the other end of the second lever arm <NUM>, adjacent a lower end of a lower part <NUM> of the second lever arm <NUM>, there is arranged a contact member <NUM> for active contact with a clamping element <NUM>.

The threads of the threaded shaft <NUM> are arranged mirror symmetrically on each side of the driving sleeve <NUM>. Accordingly, the contact members <NUM>, <NUM> of the lever arms <NUM>, <NUM> will move towards or away from each other dependent on the direction of rotation of the shaft <NUM>. Thanks to having exactly the same configuration, but mirror symmetrically, the movement will be synchronized on both sides, i.e. moving the contact devices <NUM>,<NUM> outwards simultaneously or inwardly simultaneously.

Hence, when driving the transmission in a first direction the contact members <NUM> of the first lever arms <NUM> may be used to push clamps <NUM> into clamping action for a rail <NUM>, whereas when driving the transmission in a second direction the contact members <NUM> of the second lever arms <NUM> may be used to push clamps <NUM> into clamping action for a rail <NUM>, thanks to providing a sufficient distance between each pair of facing contact members <NUM>, <NUM> that enables the positioning of a clamp <NUM> in between. It is evident for the skilled person that merely one pair of lever arms <NUM> may suffice to both push clamps <NUM> into place and remove clamps <NUM>, respectively, by adjusting the position of the contact members <NUM> to a desired position (inside of or outside of the clamps <NUM>) prior to use.

By use of basically the same power and transmission means <NUM>, <NUM> for rotatably driving the threaded shaft <NUM> as is used for driving weld cutting jaws, as disclosed in <CIT> the machine may be made substantially lighter than known machines. In the following the principle of using that power and transmission means <NUM>, <NUM> will be described in relation to schematically revised figures used in <CIT>, i.e. originally showing a weld cutting machine. In <FIG> there is shown a perspective view of such a weld cutting machine <NUM> and in and in <FIG> there is shown a perspective view of an outgoing part <NUM> of a preferred transmission mechanism <NUM>.

It is to be noted that in a preferred embodiment according to the invention, see <FIG>, there is merely needed one threaded shaft <NUM>, i.e. not two shafts as shown in <FIG>, <FIG>. It is evident that the skilled person will have no problem in understanding that a single shaft <NUM> may preferably be positioned centrally, i.e. below the central chain wheel <NUM> (shown in <FIG>) and that then there will merely be needed one central chain wheel <NUM>.

However, it is not excluded that two parallel shafts <NUM> may be of use in an alternate embodiment, i.e. having two parallel shafts <NUM> assisting in driving each lever arm <NUM>.

A relatively small high-speed electric motor <NUM> operates the transmission mechanism <NUM> adapted for the purpose of providing a desired transmission.

The transmission mechanism <NUM> comprises, two parts. On the one hand, a planetary gear <NUM> (preferably including an arrangement, shown in <FIG>) driven by the output shaft <NUM> of the motor <NUM> and a chain/wheel mechanism <NUM> (see <FIG>) driven by the output <NUM> from the planetary gear <NUM>.

The drive shaft/s <NUM> extend along the same longitudinal direction as the motor <NUM> and as shown in <FIG> in both directions away from the driving sleeve <NUM>.

The driving sleeve <NUM> may be rotation wise fixed onto the shaft <NUM> by means of form fitting, e.g. splines. However, it is evident for the skilled person that the driving sleeve <NUM> may be fixed to the shaft <NUM> in various manners, e.g. by means of welding, fixation screws, etc. Further, it is evident for the skilled person that the shaft <NUM> will have to protrude the same distance on both sides of the driving sleeve <NUM> in accordance with actual invention, wherein the direction of the threads on each side of the driving sleeve <NUM> are opposite to each other. As a consequence, upon rotation of the drive shaft <NUM>, the lever arms <NUM> will move in the desired directions either increasing or decreasing the distance between the contact members <NUM>, depending on the rotational direction.

The support structure/housing <NUM> may include a separate housing <NUM>, <NUM>, <NUM> of the transmission mechanism <NUM>, similarly as shown in <FIG>. Inside, that housing or a common housing <NUM>, there is a chain/wheel mechanism <NUM>, which in the preferred embodiment will merely drive one drive sleeve <NUM> (see <FIG>), i.e. to transfer torque from the chain/wheel mechanism <NUM> to the drive shaft <NUM>.

The output shaft <NUM> from the planetary gear <NUM> may preferably have a fixed position within the support structure. There may preferably be arranged a transversal wall <NUM> providing support for bearings/parts of the transmission mechanism <NUM>, e.g. a first supporting structure <NUM> for the motor <NUM> that is attached to an inner side of the transversal wall <NUM>. Further there may be a second supporting structures <NUM>, providing support for the drive member <NUM> of the drive shaft <NUM>.

The output <NUM> of the planetary gear <NUM> drives a shaft having one central chain wheel <NUM> fixed thereto that drives the chain <NUM> that drives the chain wheel <NUM> attached to the driving sleeve <NUM>. (Alternatively, if two shafts <NUM>, one chain 321A drives an output chain wheel <NUM> at one side of the housing, and another chain 321B symmetrically positioned drives another chain wheel <NUM> at the opposite side of the upper part of the housing). The chain/wheel mechanism <NUM> thereby may transfers an output rotating torque to the (torque transmitting) drive sleeve <NUM> connected the shaft <NUM>, which thereby moves the lever arms <NUM>, <NUM> synchronously.

In <FIG> the design of the planetary gear <NUM> is shown in more detail. The motor <NUM> and the planetary gear <NUM> are attached to opposite sides of the fixed support wall <NUM>, i.e. the planetary gear <NUM> is attached to a first side of the support wall <NUM>, whereas the motor <NUM> is attached to the second side of the support wall <NUM>. Hence the output shaft <NUM> of the motor <NUM> passes through the support wall <NUM> through central passages <NUM> of the shaft with the central chain wheel <NUM>.

At the outer end of the motor output shaft <NUM> there are dents forming a sun wheel <NUM> that mesh with dents <NUM> at the inner side of planet wheels <NUM> of the planet assembly <NUM>. The planet assembly <NUM> includes three circular planet wheels <NUM> symmetrically attached to a planet carrier <NUM>, having a central collar <NUM> providing support/bearing (not shown). Hence, the planet carrier <NUM> may rotate together with the planet wheels <NUM>. The planet wheels <NUM> at their outer sides mesh with dents of a fixed ring wheel (not shown) and also with dents <NUM> of a rotatable ring wheel <NUM>. The rotatable ring wheel <NUM> is non rotatably attached via dents <NUM> at its inner periphery to a shaft (not shown) carrying the two central chain wheels <NUM> and thereby drives the chain/wheel mechanism <NUM>. In the preferred embodiment the planetary gear is a harmonic gear, i.e. the rotatable ring wheel <NUM> and the fixed ring wheel have different amounts of dents, e.g. <NUM> and <NUM> respectively, which provides for a drastic reduction of the rotational speed from the motor shaft <NUM> to the rotate able sun wheel <NUM>.

In an exemplary embodiment the number of dents <NUM> of the motor shaft <NUM> is <NUM> and each planet (3pcs) has <NUM> dents. In combination with a ring wheel (first outer ring) that is fixed having <NUM> dents and a rotatable ring wheel (second outer ring) having <NUM> dents there will be achieved a gear ratio of <NUM>:<NUM>, i.e. when the sun wheel has made <NUM> turns, each planet has made one turn (<NUM> degrees) and thereby have driven the rotate able outer ring <NUM>/<NUM> of a turn.

Thanks to the transmission mechanism <NUM> and its combination of the (preferably harmonic kind) planetary gear <NUM> and the chain/wheel mechanism <NUM>, an extra reliable and compact torque transfer/rotational motion may be provided to the drive shaft/s <NUM>.

The use of an electric motor <NUM> may further provide the advantage that an adaptive torque/speed is automatically created to the drive shaft <NUM>, in that the higher the resistance the lower the transmitted speed to the drive rods <NUM>, i.e. when the resistance increases the rotational speed is reduced and the torque of the motor <NUM> increases and thus the force that effect the moving lever arms <NUM>, <NUM>. Preferably an out board electric motor <NUM> is used that may provide a larger torque than traditional motors.

<FIG> indicates that there is a kind of support structure that fixates basics parts of machine <NUM>, e.g. the electric motor <NUM>, the fixed wall <NUM> of the chain/wheel gearing <NUM>, the planetary gearing <NUM> and other parts that need to be fixated. Moreover, there may be a housing <NUM> that have grips/handles (not shown) attached thereto for ease of carrying and lifting the machine.

In operation of the machine is transported to a desired rail part, having clamping members <NUM> that are to be handled. The transportation may easily be performed by carrying the machine by hand. A protective plate may be arranged at the bottom of the gear wheel housing <NUM>, <NUM>, <NUM>, or the larger housing <NUM>, in order to enable the machine to be put down also on uneven ground without risk of causing damages. The machine is then lifted on to the rail <NUM> having the clamping members <NUM> that is to be handled. The rail <NUM> will fit into a rail fit recess <NUM> of the machine <NUM>, which has the form of an inverted U.

A batterie, (not shown), which may be carried separately, is positioned in a batterie holder <NUM>, see <FIG>, preferably positioned on top (not shown) of the housing <NUM>. The batterie provides power to the electric motor <NUM> and also a control unit <NUM>, e.g. attached to upper side of the housing <NUM>.

Now the machine <NUM> is ready to be operated. First it is operated to position the contact members <NUM>, <NUM> at a desired position in relation to the clamping member that are to be handled, e.g. to be pushed in as shown in <FIG>. Once the machine is started the electric motor <NUM> starts spinning whereby the rotation will be transmitted first to the planetary gearing <NUM> and then to the chain/wheel gear <NUM> to rotate the drive shaft <NUM> in a first direction, whereby the lever arms <NUM>, <NUM> will start moving towards each other and start pushing the clamping elements <NUM> against each other to securely clamp the rail <NUM>.

To remove clamps <NUM> from the rail <NUM> the machine is operated in a similar manner, but starting with the lever arms <NUM>, <NUM> in an inner position to have the contact devices <NUM> of the second lever arms <NUM> to be inside of and in level with the clamping members <NUM>. Thereafter the machine <NUM> is started and rotated in a second direction.

Claim 1:
Rail clamp handling arrangement, for moving a clamping element (<NUM>) from a position in which said element fastens a rail (<NUM>) to a railroad sleeper to a sleeper releasing position or vice-versa, comprising a support structure (<NUM>, <NUM>) having a lower part (<NUM>) and an upper part (<NUM>), said lower part (<NUM>) having a central rail fitting recess (<NUM>) and arranged to extend transversally in relation to a central plane (C) common with the longitudinal extension of the rail (<NUM>) when in operation, wherein there is arranged a pair of mirror symmetrically arranged pivotable lever arms (<NUM>, <NUM>) and wherein said lower part (<NUM>) is arranged with connection means providing pivot points (<NUM>, <NUM>) at an intermediate point of said pair of pivotable lever arms (<NUM>, <NUM>), a power and transmission arrangement (<NUM>, <NUM>, <NUM>) arranged to simultaneously move an upper part (<NUM>, <NUM>) of said lever arms (<NUM>,<NUM>) via an upper pivotal connection (<NUM>, <NUM>), a lower part (<NUM>,<NUM>) of said lever arms (<NUM>, <NUM>) comprising contact devices (<NUM>, <NUM>) arranged to move a clamping element (<NUM>), wherein said power and transmission arrangement (<NUM>, <NUM>, <NUM>) includes a power unit in the form of an electric motor (<NUM>) attached to said upper part (<NUM>) and a rotatable threaded shaft (<NUM>) having oppositely arranged threads to transfer torque applied via said power and transmission arrangement (<NUM>, <NUM>, <NUM>) into pivotal mirror wise movement of said lever arms (<NUM>, <NUM>), wherein said transmission arrangement (<NUM>, <NUM>, <NUM>) includes a first part attached to said upper part (<NUM>).