The invention relates to a wire saw according to the preamble of claim 1 and to a wire saw according to the preamble of claim 18.

JPH07153724A discloses a wire saw for slicing silicon ingots. The wire saw comprises wire guide rollers supporting a wire web and spools for supplying cutting wire to the wire web and for taking-up cutting wire from the wire web. A housing cassette is provided with grooves for accommodating the silicon wafers

WO2013018556A1 discloses a wire saw comprising wire guide rollers across which the cutting wire is suspended in multiple loops. Bobbins are provided on the supply side and winding side of the wire web. Sensors are provided to measure the tension of cutting wire between the wire guide rollers and the bobbins.

Disadvantages in prior art occur due to the fact that the foot print of such wire saws and thus the space required for installation is very large. Moreover the cutting area (comprising the wire guide rollers and the wire web) is not sufficiently separated from the area in which the pulleys and/or spools for (temporarily) storing cutting wire are arranged. Cutting liquid, dirt and material particles have an adverse impact on spools, and the wire thereon, deflection pulleys and tension means. Cleaning and maintenance of wire saws are time wasting and expensive procedures. Moreover, damages at the force measuring system and the pulley bearing may occur.

EP2650070A1 discloses a wire saw comprising wire guide rollers spanning a wire web a storage spools for unused wire on one side and used wire on the other side of the wire web. The storage spools are arranged in lateral housings.

The disadvantage of such a solution consists in the fact, that the accessibility of component parts such as the wire guide rollers and pulleys from outside the wire saw is very poor. In addition the housing is very complex.

The object of the invention is to overcome the problems mentioned above and to provide a wire saw in which cutting wire that is not part of the cutting field as well as pulleys and/or spools for guiding and/or storing the cutting wire are efficiently protected from the adverse effects of cutting liquid, dirt and material particles. Further, the wire saw should allow for optimal accessibility to the wire saw, particularly to the cutting wire path extending between the wire web (i.e. cutting field) and a storage spool.

The object is achieved by means of a wire saw for cutting a piece of material, particularly for slicing, squaring and/or bricking a piece of semiconductor material and/or for cutting a plurality of wafers from a workpiece, comprising:

a first compartment in which wire guide rollers for supporting a cutting field formed from a cutting wire are arranged, wherein the wire saw further comprises a second compartment in which a first cutting wire spool for storing, at least temporarily, cutting wire in multiple loops is arranged,

a first cutting wire path extending from one of the wire guide rollers to the first cutting wire spool,

wherein the second compartment is arranged at least partially below, preferably directly below and/or completely below, the first compartment

and/or wherein the first cutting wire spool is arranged below, preferably in vertical direction below the first compartment

and/or wherein the first cutting wire spool is at least partially, preferably completely arranged below, preferably in vertical direction below, the cutting field.

Such an arrangement allows for a space-saving design with effectively reduced foot print.

"directly below" means "in vertical direction below", i.e. that the second compartment is arranged in vertical direction below the first compartment.

Due to the arrangement of the first cutting wire spool in the immediate vicinity of the wire guide rollers (i.e. below), the cutting wire path extending between a wire guide roller and the first cutting wire spool may be effectively reduced. Shorter "free wire" reduces vibrations in the system, while keeping the foot print low and the component parts that require maintenance (such as spools) accessible.

In a preferred embodiment the first cutting wire spool is mostly arranged in vertical direction below the cutting field.

In a preferred embodiment the first cutting wire spool completely overlaps with the first compartment in vertical direction.

In a further preferred embodiment the first cutting wire spool at least partially, preferably completely, overlaps with the cutting field (wire web) in vertical direction. In a preferred embodiment the length of the first cutting wire path - beginning at the wire guide roller and ending at the first cutting wire spool - is less than three times the length of the wire guide roller, preferably less than two times the length of the wire guide roller. Due to the design of the wire saw it is possible to reduce the cutting wire path(s) between the wire guide rollers and the cutting wire spools. It is very advantageous to have a short wire transfer path. Particularly, time and efforts for maintenance, exchange of wire and/or cleaning are efficiently reduced. In addition thinner cutting wires can be used because the wire vibrates less resulting in less kerf and thus more efficient cutting. In a preferred embodiment the length of the first cutting wire path - beginning at the wire guide roller and ending at the first cutting wire spool - is shorter than 1,5 meter, preferably shorter than 1 meter.

In a preferred embodiment at least 50%, preferably at least 60% of the first cutting wire path extends besides the wire guide roller and/or parallel to the wire guide roller.

Preferably, the first cutting wire path does not extend - in axial direction of the wire guide roller(s) - beyond the wire guide roller(s). Preferably, the second cutting wire path does not extend - in axial direction of the wire guide roller(s) - beyond the wire guide roller(s). With other words: the cutting wire path(s) does/do not extend to the "left and right" of the wire guide roller(s). Also here the footprint of the wire saw may be efficiently reduced, particularly in axial direction of the wire guide rollers.

In a preferred embodiment the wire saw comprises

a third compartment in which a second cutting wire spool for storing, at least temporarily, cutting wire in multiple loops is arranged,

a second cutting wire path extending from one of the wire guide rollers to the second cutting wire spool,

wherein the third compartment is arranged at least partially below, preferably directly below, the first compartment,

and/or wherein the second cutting wire spool is arranged below, preferably in vertical direction below the first compartment. In an alternative the first and/or second cutting wire spool may be at least partially, preferably completely arranged below, preferably in vertical direction below, the cutting field.

In the following embodiments will be described by means of the second compartment, first cutting wire spool, first cutting wire path, first opening, etc. However, in alternative embodiments the same features may be transferred to the third compartment, second cutting wire spool, second cutting wire path, second opening.

Preferably, the first cutting wire spool and/or the second cutting wire spool is/are arranged in vertical direction below the first compartment.

Preferably, the first cutting wire spool and/or the second cutting wire spool is/are arranged in vertical direction below the cutting field.

In a preferred embodiment the first cutting wire spool and/or the second cutting wire spool completely overlap(s) with the first compartment in vertical direction. Preferably, the first cutting wire spool and/or the second cutting wire spool completely overlap with the cutting field (in vertical direction).

In a preferred embodiment the length of the second cutting wire path - beginning at the wire guide roller and ending at the second cutting wire spool - is less than three times the length of the wire guide roller, preferably less than two times the length of the wire guide roller.

In a preferred embodiment the length of the second cutting wire path - beginning at the wire guide roller and ending at the second cutting wire spool - is shorter than 1,5 meter, preferably shorter than 1 meter.

In a preferred embodiment at least 50%, preferably at least 60% of the second cutting wire path extends besides the wire guide roller and/or parallel to the wire guide roller.

Preferably, the bottom wall of the first compartment forms the ceiling of the second compartment and/or the ceiling of the third compartment. The bottom wall may be part of or mounted to the (load carrying) frame of the wire saw. Preferably, the second compartment and the third compartment are arranged side by side and separated from each other by a, preferably vertical, partition wall, wherein preferably the partition wall extends below, preferably centrally below, the first compartment.

In a preferred embodiment the second compartment and the third compartment are in communication with each other. For this purpose the partition wall separating the compartments from each other may have at least one opening.

Preferably, the first cutting wire spool is rotatably mounted to a first side of the partition wall, preferably by means of at least one screw, and the second cutting wire spool is rotatably mounted to a second side of the partition wall, preferably by means of at least one screw, which second side is opposite to the first side. Preferably, the wire saw comprises a frame supporting the wire guide rollers, wherein the partition wall forms a load carrying portion of the frame. Here, the partition wall is used for two functions: carrying load, particularly load of the wire guide rollers; and, at least partially separating the second compartment from the third compartments. Overall weight of the wire saw may be reduced efficiently, while keeping the frame stiff, what is needed for accurate cutting.

Preferably, the partition wall has at least one foot, which is arranged vertically below the first compartment. The foot effectively and preferably symmetrically transfers forces into the ground.

In preferred embodiments

the first cutting wire spool has or is connected to a first drive, preferably a motor, wherein preferably the first drive is arranged in the second compartment, and/or the second cutting wire spool has or is connected to a second drive, preferably a motor, wherein preferably the second drive is arranged in the third compartment. Preferably, the wire saw comprises a cutting wire forming the cutting field and extending along the first cutting wire path, wherein preferably the cutting wire is a fixed abrasive wire, more preferred a diamond wire.

Preferably, the weight of the wire saw amounts to at least 4000 kg, preferably to at least 5500 kg.

Preferably, the weight carried by the foot (of the partition wall), which is arranged vertically below the first compartment, amounts to at least 1800 kg, preferably to at least 2200 kg. Preferably, the diameter of at least one of the wire guide rollers amounts to at least 12 cm, preferably to at least 15 cm.

Preferably, the wire receiving surface of at least one of the wire guide rollers is formed from a plurality of wire guiding grooves.

Preferably, at least one of the wire guiding rollers is rotatably mounted to the frame of the wire saw by means of at least one ball bearing and/or at least one roller bearing.

Preferably, at least one of the wire guiding rollers and/or the first cutting wire spool and/or the second cutting wire spool is/are at least partially formed from metal, preferably steel, and/or from polymer, preferably reinforced polymer.

Preferably, a horizontal cross-section of the wire saw's frame is T-shaped. The middle leg of the T-shape is formed by the partition wall. Here, a stable construction is achieved.

Preferably, a horizontal cross-section of the wire saw's frame comprises a T-shaped portion, wherein preferably the T-shaped portion forms at least a part of the partition wall.

Preferably, the partition wall is made from metal, preferably steel, and/or from mineral casting.

Preferably, the thickness of the partition wall amounts to at least 4 cm, preferably at least 7 cm .

Preferably, the partition wall has a hollow profile.

Preferably, the partition wall and at least parts of the walls enclosing the first compartment are made from mineral casting, wherein preferably the partition wall and at least parts of the walls enclosing the first compartment are casted as to form one massive part, preferably being casted in one go.

Preferably, the second compartment and/or the third compartment is/are (respectively) delimited by at least one door that delimits that compartment in a first direction and in a second direction which is different from the first direction, wherein preferably the angle between the first direction and the second direction amounts to at least 45°, even more preferably to at least 80°, such as essentially 90°. Preferably, the second compartment and/or third compartment is/are (respectively) delimited by at least one door that has a general L-shape, both legs of the "L" delimiting the compartment.

The object may be also achieved - also independent of the foregoing invention and aspects - by a wire saw for cutting a piece of material, particularly for slicing, squaring and/or bricking a piece of semiconductor material and/or for cutting a plurality of wafers from a workpiece, particularly according to one of the preceding claims, comprising:

a housing and

a first compartment in which wire guide rollers for supporting a cutting field formed from a cutting wire are arranged,

wherein the wire saw comprises:

a second compartment in which a first cutting wire spool for storing, at least temporarily, cutting wire in multiple loops is arranged,

a first cutting wire path extending from one of the wire guide rollers to the first cutting wire spool,

wherein at least a portion of the first cutting wire path, preferably the entire first cutting wire path, is accessible, preferably continuously accessible, from outside the wire saw through a first opening formed in the housing of the wire saw. The second compartment is separated from the first compartment. The cutting wire extends from the first compartment to the second compartment. By the first opening the accessibility is highly increased. The cutting wire path, that may include deflection pulleys for deflecting the cutting wire, and its surroundings may be cleaned and maintained easily. Exchange of the cutting wire becomes uncomplicated and time saving.

The first cutting wire path extends from one of the wire guide rollers to the first cutting wire spool. I.e. the first cutting wire path is defined as a cutting wire path which starts at one of the wire guide rollers and ends at the first cutting wire spool. In the same way the second cutting wire path (see below) is defined as cutting wire path which starts at one of the wire guide rollers and ends at the second cutting wire spool.

In the present application "accessible from outside the wire saw" means: accessible by an operator who stands outside the wire saw. With other words: an operator standing outside the wire saw is able to handle - i.e. clean, remove, exchange and/or maintain - corresponding part(s), i.e. at least parts extending and/or arranged along said portion of the first cutting wire path, preferably the complete wire in the first cutting wire path, particularly the cutting wire itself and/or deflection pulleys and/or a (linear) guide e.g. for guiding a deflection pulley and/or the cutting wire spool. It is preferred if the operator is able to see the complete first cutting wire path from outside the wire saw.

"Continuously accessible from outside the wire saw" means that a continuous access is provided to the cutting wire path without interruptions. The overall cutting wire path is not hidden by any obstacles and/or not guided through holes. Particularly, the cutting wire or an imaginary wire can be drawn from the cutting wire spool to the wire guide rollers, possibly passing pulleys, but without guiding it through holes and preferably without letting it pass behind frame parts from the point of view of the operator (which stands outside the wire saw). Moreover, the end portion of the cutting wire can be held by the operator, e.g. by means of a gripper or by his hand, and brought from the cutting wire spool to the wire guide rollers without letting it go (possibly giving it over to another griper or hand) and thus place it in its position for cutting.

Preferably, said accessible portion of the first cutting wire path is arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the opening plane (plane of the housing in which the first opening is formed) and/or behind an openable cover covering the first opening (in the operational state). Here, the operator has to put only his hands and arms into the wire saw.

In a preferred embodiment the entire first cutting wire path is accessible, preferably continuously accessible, from outside the wire saw through the first opening formed in the housing of the wire saw.

In a preferred embodiment each point of the first cutting wire path beginning at the wire guide roller and ending at the first cutting wire spool is arranged less than 40 cm, preferably less than 30 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening. In a preferred embodiment each point of the first cutting wire path beginning at the wire guide roller and ending at the first cutting wire spool is visible from outside the wire saw through the first opening, preferably from one point outside the wire saw. In a preferred embodiment a surface portion of the wire guide roller from which the first cutting wire path extends to the first cutting wire spool is arranged less than 40 cm, preferably less than 30 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening. In a preferred embodiment a portion of the first cutting wire path begins at the wire guide roller and ends at a first deflection pulley, which along the first cutting wire path is the closest pulley to the wire guide roller, and wherein this portion of the first cutting wire path is accessible, preferably continuously accessible, from outside the wire saw through the first opening, wherein preferably each point of this portion of the first cutting wire path is arranged less than 40 cm, preferably less than 30 cm, more preferred less than 20 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening.

In a preferred embodiment the length of the first cutting wire path - beginning at the wire guide roller and ending at the second cutting wire spool - is less than three times the length of the wire guide roller, preferably less than two times the length of the wire guide roller.

In a preferred embodiment the length of the first cutting wire path - beginning at the wire guide roller and ending at the first cutting wire spool - is shorter than 1,5 meter, preferably shorter than 1 meter. In a preferred embodiment at least 50%, preferably at least 60% of the first cutting wire path extends besides the wire guide roller and/or parallel to the wire guide roller.

In a preferred embodiment the wire saw comprises a third compartment in which a second cutting wire spool for storing, at least temporarily, cutting wire in multiple loops is arranged, and a second cutting wire path extending from one of the wire guide rollers to the second cutting wire spool, wherein the second cutting wire path is accessible, preferably continuously accessible, from outside the wire saw through a second opening formed in the housing of the wire saw. While the one of the second and third compartments accommodates the spool for supplying (unused) cutting wire to the wire web, the other compartment accommodates the spool for receiving (used) cutting wire from the wire web.

Preferably, said accessible portion of the second cutting wire path is arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the opening plane (plane of the housing in which the second opening is formed) and/or behind an openable cover covering the second opening (in the operational state). Here, the operator has to put only his hands and arms into the wire saw.

In the following embodiments will be described by means of the second compartment, first cutting wire spool, first cutting wire path, first opening, etc. However, in alternative embodiments the same features may be transferred to the third compartment, second cutting wire spool, second cutting wire path, second opening.

Preferably, the first opening is formed on a first side of the wire saw and the second opening is formed on a second side of the wire saw, wherein preferably the second side is opposite to the first side and wherein preferably the first side and the second side extend along, preferably essentially parallel to, the rotational axes of the wire guide rollers. While the first and second cutting wire paths are spatially separated from each other, high accessibility and a space-saving design may be achieved. In a preferred embodiment the first cutting wire path comprises at least one, preferably at least two, more preferred at least three, rotatable deflection pulley(s) for deflecting the cutting wire, wherein the at least one, preferably at least two, more preferred at least three, deflection pulley(s), is/are accessible from outside the wire saw through the first opening.

Preferably, the at least one deflection pulley is arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening.

In such a way the deflection pulleys, which are prone to wear and contamination, may be easily cleaned, exchanged and maintained. Preferably, the first cutting wire path comprises rotatable deflection pulleys for deflecting the cutting wire, wherein each of the deflection pulleys is accessible by an operator from outside the wire saw through the first opening, wherein preferably the at least three deflection pulleys are arranged less than 40 cm, preferably less than 30 cm, more preferred less than 20 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening.

Preferably, a main portion of the first cutting wire path extends between a first deflection pulley, which along the first cutting wire path is closest to one of the wire guide rollers, and a second deflection pulley, which along the first cutting wire path is closest to the first cutting wire spool, and wherein the main portion of the first cutting wire path is accessible, preferably continuously accessible, from outside the wire saw through the first opening.

Preferably, each point of the main portion of the first cutting wire path is arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the plane of the first opening and/or behind an openable cover covering the first opening.

Preferably, the first cutting wire path comprises a third deflection pulley which along the first cutting wire path is arranged between the first deflection pulley and the second deflection pulley, wherein preferably the third deflection pulley is a tensioning pulley for tensioning the cutting wire.

Preferably, the rotational axis of the at least one deflection pulley extends transverse, preferably perpendicular, to the rotational axis of the cutting wire spool. In such a way a space saving design may be achieved, since the run of the cutting wire path may be oriented along the rotational axis of the wire guide rollers (spanning the cutting field).

Preferably, the at least one deflection pulley, preferably all deflection pulleys, of the first cutting wire path is/are arranged in the second compartment. Here, they are optimally protected from dirt, moisture, and particles emanating from the first compartment (i.e. cutting compartment).

Preferably, at least 25%, preferably at least 50% of the first cutting wire path extends along, preferably essentially parallel to, the rotational axes of the wire guide rollers, preferably at least in one position of deflection pulley(s), preferably of second deflection pulley. This results in a space-saving design, since the dimensions of the wire saw perpendicular to the rotational of the wire guide rollers may be significantly reduced. Preferably, the first opening is formed on a first side of the wire saw, wherein the first side extends along, preferably parallel to, the rotational axes of the wire guide rollers. This aspect also optimized space-saving design.

Preferably, at least one of the wire guide rollers is accessible, preferably continuously accessible, preferably along its entire length, through the first opening. Here, the first opening gives not only access to the second compartment but also to the first compartment.

Preferably, the first cutting wire spool is accessible, preferably continuously accessible, preferably along its entire length, through the first opening. Preferably, the first cutting wire spool is accessible, preferably through the first opening, along its entire length from a first side of the wire saw, said first side extending along, preferably essentially parallel to, the rotational axes of the wire guide rollers.

Preferably, an end face of the first cutting wire spool is accessible, preferably through the first opening, from a third side of the wire saw, wherein the third side extends transverse, preferably perpendicular to the rotational axes of the wire guide rollers.

Preferably, the first cutting wire spool is removably mounted to the wire saw wherein the first cutting wire spool may be removed from the wire saw by axial movement only. This facilitates exchange of spools, since only one movement in one direction is necessary.

Preferably, the rotational axis of the first cutting wire spool is essentially parallel to the rotational axes of the wire guide rollers. Here also a space-saving design may be achieved. Preferably, the housing comprises at least one openable cover which in the closed state covers the first opening at least partially. The cover may be e.g. a slidable cover, a hinged cover (e.g. in form of a door), a flexible cover or a (roller) shutter.

Preferably, the wire saw comprises a cutting wire feedthrough for guiding the cutting wire from the first compartment to the second compartment.

The cutting wire feedthrough may be e.g. formed as an opening or a duct, preferably a (straight) tube. The second compartment which is separated from the first compartment allows to accommodate a portion of the cutting wire, preferably also (deflection and/or tension) pulleys and/or spools for storing cutting wire. The cutting wire coming from the cutting field extends through the feedthrough and runs and/or is (temporarily) stored within the second compartment. The cutting wire feedthrough may protect the cutting wire when passing from the first compartment to the second compartment. The feedthrough may be provided in a (openable) wall separating the second compartment from the first compartment.

Preferably, the wire saw comprises a first openable cover having a first (i.e. closing) edge, preferably in form of a flexible sealing or lip, which in the closed state of the first cover faces or lies against a second, preferably stationary edge, preferably in form of a flexible sealing or lip, and which in the opened state of the first cover is distanced from the second edge, wherein the cutting wire feedthrough extends between the first edge and the second edge. Here, direct access is provided to the corresponding cutting wire portion when opening the first cover. This allows for simple exchange of cutting wire. The flexible sealing or lip prevents cutting liquid, dirt and moisture from entering the second compartment.

Preferably, the housing comprises a first openable cover and a second openable cover, wherein the first cover covers at least partially, preferably mainly, the first compartment and the second cover covers at least partially, preferably mainly, the second compartment. It is preferred if the covers may be opened independently of each other.

Preferably, in the closed state of the covers the first cover and the second cover are adjacent to each other, preferably touch each other. Further embodiments of the invention are indicated in the figures and in the dependent claims. The list of reference marks forms part of the disclosure. The invention will now be explained in detail by the drawings. In the drawings:

Fig. 1 shows a wire saw according to the invention,

Fig.2 shows a preferred embodiment of an inventive wire saw, Fig.3 shows parts of a wire saw from a top view,

Fig.4 shows a side view of a wire saw, Fig. 5 the transition area of cutting wire between first and second

compartment with openable cover,

Fig. 6 a view through the opening giving access to the cutting wire path,

Fig. 7 a wire saw with an operator gripping through the opening. Fig. 1 schematically shows a wire saw 10 for cutting a piece of material (indicated as square in the area of the cutting field 5), particularly for slicing, squaring and/or bricking a piece of semiconductor material and/or for cutting a plurality of wafers from a workpiece. The wire saw 10 comprises a housing 4. In the housing 4 wire guide rollers 13, 14 are arranged within a first compartment 1. Wire guide rollers 13, 14 support a cutting field 5 formed from a cutting wire 6.

The wire saw 10 also comprises a second compartment 2 in which a first cutting wire spool 11 for storing, at least temporarily, cutting wire 6 in multiple loops (also called: storage spool; e.g. for unused wire) is arranged. A first cutting wire path 7 extends from one of thewire guide rollers 13 to the first cutting wire spool 11. The wire saw 10 also comprises a third compartment 3 in which a second cutting wire spool 12 for storing, at least temporarily, cutting wire 6 in multiple loops (also called: storage spool; e.g. for used wire) is arranged. A second cutting wire path 8 extends from one of the wire guide rollers 14 to the second cutting wire spool 12.

It would be possible to have an additional spool attached to the first and or second cutting wire spool 11 which additional spool may be used for temporarily receiving cutting wire (which is currently in use) in non-overlapping wires.

The rotational axis of the first cutting wire spool 11 and the rotational axis of the second cutting wire spool 12 are essentially parallel to the rotational axes of the wire guide rollers 13, 14. As can be seen from Fig. 1 and 3 at least a portion of the first cutting wire path 7 (here: the entire first cutting wire path 7) is accessible from outside the wire saw 10 through a first opening 19 formed in the housing 4.

In the preferred embodiment of Fig. 3 at least a portion of the second cutting wire path 8 (here: the entire second cutting wire path 8) is accessible through a second opening 20 formed in the housing 4. As can be seen, the respective cutting wire path is not hidden by any obstacles and/or not guided through holes so that it can be completely accessed through the respective opening 19, 20.

It is preferred if said accessible portion of the second cutting wire path 8 is arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the plane of the respective opening 20 and/or behind an openable cover 16 (see Fig. 1 and 4) covering the respective opening 20.

As can be seen particularly from Fig. 3 the first opening 19 is formed on a first side of the wire saw 10 and the second opening 20 is formed on a second side of the wire saw 10. The second side is opposite to the first side. The first side and the second side extend along (here: essentially parallel to) the rotational axes of the wire guide rollers 13, 14.

As can be seen from Fig. 1-3 the first cutting wire path 7 comprises three rotatable deflection pulleys 9a, 9b, 9c for deflecting the cutting wire 6. The deflection pulleys 9a, 9b, 9c are accessible from outside the wire saw 10 through the first opening 19. It is preferred if the deflection pulleys 9a, 9b, 9c are arranged less than 40 cm, preferably less than 30 cm preferably less than 20 cm, behind the plane of the first opening 19 and/or behind an openable cover 16 covering the first opening 19.

A main portion of the first cutting wire path 7 extends between a first deflection pulley 9a, which along the first cutting wire path 7 is closest to one of the wire guide rollers 13, and a second deflection pulley 9c, which along the first cutting wire path 7 is closest to the first cutting wire spool 11. The main portion of the first cutting wire path 7 is accessible from outside the wire saw 10 through the first opening 19. The first cutting wire path 7 also comprises a third deflection pulley 9b which along the first cutting wire path 7 is arranged between the first deflection pulley 9a and the second deflection pulley 9c. The third deflection pulley 9c is a tensioning pulley (i.e. an adjustable or moveable pulley) for tensioning the cutting wire 6.

The rotational axes of the deflection pulleys 9a, 9b, 9c extend transverse, preferably perpendicular, to the rotational axis of the first cutting wire spool 11 and/or to the rotational axes of the wire guide rollers 13, 14. As can be seen from Figs. 1-3 all deflection pulleys 9a, 9b, 9c of the first cutting wire path 7 are arranged in the second compartment 2. As can be seen from Fig. 3 at least 50% of the first cutting wire path 7 extends along, preferably essentially parallel to, the rotational axes of the wire guide rollers 13, 14. As can be seen from Fig. 2 one of the wire guide rollers 13 is accessible along its entire length through the first opening 19. Also, the first cutting wire spool 11 is accessible along its entire length through the first opening 19.

As can be seen from Fig. 2 the first cutting wire spool 11 is accessible through the first opening 19 not only along its entire length from a first side but also from a third side, wherein the third side extends transverse, preferably perpendicular to the rotational axes of the wire guide rollers 13, 14.

The first cutting wire spool 11 is removably mounted to the wire saw 10. It is preferred if the first cutting wire spool 15 is removable from the wire saw 10 by axial movement only (Fig.2). In a preferred aspect of the invention housing 4 comprises at least one openable cover 15, 16 which in the closed state covers the first opening 19 at least partially. The cover(s) are not shown in Fig.2 and 3, but are apparent from Figs. 1 and 4.

As can be seen from the wire saw 10 comprises at least one cutting wire feedthrough 21 for guiding the cutting wire 6 from the first compartment 1 to the second compartment 2 (or to the third compartment 3). In the embodiment of Fig. 5 the wire saw 10 comprises a first openable cover 15 having a first (closing) edge 17, preferably in form of a flexible sealing or lip, which in the closed state of the first cover 15 faces or lies against a second stationary edge 18, preferably also in form of a flexible sealing or lip. The cutting wire feedthrough 21 - and thus also the cutting wire 6 - extends between the first edge 17 and the second edge 18. In the opened state of the first cover 15 (dashed line in Fig. 5) the first edge 17 is distanced from the second edge 18.

In the embodiments of Fig. 1 and 4 housing 4 comprises a first openable cover 15 and a second openable cover 16, wherein the first cover 15 covers the first compartment 1 and the second cover 16 covers the second compartment 2. In the closed state of the covers 15, 16 the first cover 15 and the second cover 16 may be adjacent to each other, preferably touch each other. In a preferred aspect of the invention which may be also realized independent of the foregoing embodiments a wire saw 10 comprises:

a first compartment 1 in which wire guide rollers 13, 14 for supporting a cutting field 5 formed from a cutting wire 6 are arranged,

a second compartment 2 in which a first cutting wire spool 11 for storing, at least temporarily, cutting wire 6 in multiple loops is arranged, and

a first cutting wire path 7 extending from one of the wire guide rollers 13, 14 to the first cutting wire spool 11.

The second compartment 2 is arranged below, preferably directly below (i.e. in vertical direction below), the first compartment 1.

It is preferred if also the third compartment 3 is arranged below, preferably directly below, the first compartment 1 (see Fig. 1 and 2). Here, also the first cutting wire spool 11 and the second cutting wire spool 12 are arranged in vertical direction below the first compartment 1. The bottom wall of the first compartment 1 may form the ceiling of the second compartment 2 and/or the ceiling of the third compartment 3.

In an alternative characterization of the present invention the first cutting wire spool 11, preferably also the second cutting wire spool 12, is/are arranged below, preferably in vertical direction below the first compartment 1; and/or is/are at least partially, preferably completely arranged below, preferably in vertical direction below, the cutting field 5.

As can be seen particularly from the figs. 1 and 2 the first cutting wire spool 11 and the second cutting wire spool 12 completely overlap with the first compartment 1 in vertical direction (i.e. as seen from above). Alternatively it could be also preferred if the first cutting wire spool 11 and/or the second cutting wire spool 12 at least partially, preferably completely, overlap(s) with the cutting field 5 in vertical direction.

As can be seen in Fig.2 the length of the first cutting wire path 7 - beginning at the wire guide roller and ending at the first cutting wire spool - may be less than three times the length of the wire guide roller 13, preferably less than two times the length of the wire guide roller 13. Analogously, the length of the second cutting wire path 8 - beginning at the wire guide roller 14 and ending at the second cutting wire spool 12 - may be less than three times the length of the wire guide roller 14, preferably less than two times the length of the wire guide roller 14. In fact on this side the length can be much shorter since the cutting wire leaves wire guide roller 14 close to its deflection pulley (not shown).

In a preferred embodiment the length of the first cutting wire path 7 - beginning at the wire guide roller 13 and ending at the first cutting wire spool 11 - is shorter than 1,5 meter, preferably shorter than 1 meter.

In a preferred embodiment at least 50%, preferably at least 60% of the first cutting wire path 7 extends besides the wire guide roller 13 and/or parallel to the wire guide roller 13.

The same may hold for the second cutting wire path 8. As can be seen from Fig. 1 and 2 the second compartment 2 and the third compartment 3 are arranged side by side and separated from each other by a, preferably vertical, partition wall 22. The partition wall 22 extends below, preferably centrally below, the first compartment 1.

The first cutting wire spool 11 is rotatably mounted to a first side of the partition wall 22 (e.g. by means of screws) and the second cutting wire spool 12 is rotatably mounted to a second side of the partition wall 22 (e.g. by means of screws), which second side is opposite to the first side.

It is preferred if the partition wall 22 forms a load carrying portion of the frame 23 which also supports the wire guide rollers 13, 14. The partition wall 22 may have at least one foot 24, which is arranged vertically below the first compartment 1.

In the following further preferred embodiments are described:

The first cutting wire spool 11 may have or be connected to a first drive, preferably a motor, wherein preferably the first drive is arranged in the second compartment 2.

The second cutting wire spool 12 may have or be connected to a second drive, preferably a motor, wherein preferably the second drive is arranged in the third compartment 3.

The wire saw 10 may of course (in the operational state) comprise a cutting wire 6 forming the cutting field 5 and extending along the first cutting wire path 7. The cutting wire 6 may be a fixed abrasive wire, preferably a diamond wire. Preferably, the weight of the wire saw amounts to at least 4000 kg, preferably to at least 5500 kg.

Preferably, the weight carried by the foot (of the partition wall), which is arranged vertically below the first compartment, amounts to at least 1800 kg, preferably to at least 2200 kg.

Preferably, the diameter of at least one of the wire guide rollers amounts to at least 12 cm, preferably to at least 15 cm.

The wire receiving surface of at least one of the wire guide rollers 13, 14 is formed from a plurality of wire guiding groove.

At least one of the wire guiding rollers 13, 14 may be rotatably mounted to the frame 23 of the wire saw 10 by means of at least one ball bearing and/or at least one roller bearing.

At least one of the wire guiding rollers 13, 14 and/or the first cutting wire spool 11 and/or the second cutting wire spool 12 is/are at least partially formed from metal, preferably steel, and/or from a (reinforced) polymer.

As can be seen from Fig. 2 a horizontal cross-section of the wire saw's frame 23 may be T-shaped.

The partition wall 22 may be made from metal, preferably steel, and/or from mineral casting.

The thickness of the partition wall 22 may amount to at least 4 cm, preferably to at least 7 cm .

The partition wall 22 may have a hollow profile.

It is stated that the third compartment including the second cutting wire spool, the second cutting wire path and the second opening may be formed according to individual embodiments described and claimed for the second compartment including the first cutting wire spool, the first cutting wire path and the first opening.

Fig. 4 shows a side view of a wire saw 10 with first cover 15 and second cover 16 closing the first opening 19. The dashed line in Fig. 4 indicates that the second cover 16 may (partially) overlap with the first cover 15.

Fig. 6 shows (from outside the wire saw 10) a view through the opening 19 giving access to the cutting wire path 7. The situation for the operator standing outside the wire saw 10 is seen in Fig. 7. As can be seen from these figures the accessibility is increased, since the operator may handle the cutting wire 6 as well as deflection pulleys 9a, 9b, 9c - preferably also the cutting wire spool 11 - from outside the wire saw 10.

The invention is not restricted to the embodiments described above. Other variants will be obvious for the person skilled in the art and are considered to lie within the scope of the invention as formulated in the following claims. Individual features described in all parts of the above specification, particularly with respect to the figures may be combined with each other to form other embodiments and/or applied mutatis mutandis to what is described in the claims and to the rest of the description, even if the features are described in respect to or in combination with other features.

List of reference signs

1 first compartment

2 second compartment

3 third compartment

4 housing

5 cutting field

6 cutting wire

7 first cutting wire path

8 second cutting wire path

9a, 9b, 9c pulley

10 wire saw

11 first cutting wire spool

12 second cutting wire spool

13 wire guide roller

14 wire guide roller

15 first cover

16 second cover

17 first (closing) edge

18 second (stationary) edge

19 first opening

20 second opening

21 cutting wire feedthrough

22 partition wall

23 frame

24 foot