Band guide for a saw blade and band saw

Abstract

Band guide (1) for a saw band (2), comprising a guide body (3) on which a first metallic guide layer (51) and a second metallic guide layer (52) are formed, wherein the first guide layer (51) and the second guide layer (52) are opposite each other and define a guide gap (9) which is designed to receive a saw band section, wherein the first guide layer (51) and the second guide layer (52) are each formed as a microporous coating, and wherein a first air supply channel (39) is assigned to the first guide layer (51) to allow air to flow through the first guide layer (51), and wherein a second air supply channel (89) is assigned to the second guide layer (52) to allow air to flow through the second guide layer (52), wherein the guide body (3) has a U-shaped profile.wherein the first guide layer (51) is arranged on a first inner side (12) of a first U-leg (10) of the guide body (3) and wherein the second guide layer (52) is formed on a second inner side (14) of a second U-leg (11) of the guide body (3), wherein the second inner side (14) is arranged opposite the first inner side (12), characterized in that the first guide layer (51) is embedded in a first recess (35) of a first support plate (4) which is attached to the first inner side (12) and wherein the second guide layer (52) is embedded in a second recess (85) of a second support plate (5) which is attached to the second inner side (14).

Description

From DE 101 15 615 A1, a saw band guide for a band saw, in particular for a high-speed band saw for cutting metallic products, is known, which has guide rollers assigned to the surface of the driven saw band on the cutting-active side of the band running and at least one support roller facing the rear end edge of the saw band, wherein the support roller is designed as a truncated cone roller and its conical surface rests against the end edge of the saw band. DE 10 2019 105 959 A1 discloses a guide insert for a saw band guide for guiding a saw band with at least two band guide elements held in the guide insert, wherein at least one pair of lateral band guide elements arranged parallel and at the same height is received in the guide insert, wherein in a use position a slot for lateral guidance of the saw band is formed between a first lateral band guide element and a second lateral band guide element, wherein the band guide elements have a rotationally symmetric shape with respect to an axis of symmetry with a cylindrical friction surface,wherein the band guide elements in the operating position are each held in a cylindrical recess of the guide insert by means of releasable clamping means in a force-locking and / or form-locking manner and clamped against rotation about the axis of symmetry, and wherein by releasing the clamping means the band guide elements can be moved from a first rotational position to further rotational positions by rotation about the axis of symmetry. DE 22 36 229 A discloses a guide for supporting band-shaped tools, in particular band saw blades on band saw machines, with guide jaws arranged above and below the workpiece, on one or both sides of the band saw blade, opposite each other, on a machine-fixed and height-adjustable guide arm, the length and width of which can be selected as appropriate, wherein these guide jaws are provided with one or more air supply bores and with outlet openings (nozzles) on the guide surfaces facing the band-shaped tool and parallel to its broad sides, through which the air flows between the guide jaws and the band-shaped tool and supports the latter without contact by means of the thin air layers that form between the two. From DE 38 31 501 A1 a guide for band saws, in particular for high-speed band saws, such as diamond saws for stone processing, is known, which comprises a metal block with opposing surfaces, wherein the surfaces define a slot with a slightly greater width than the saw band thickness and are provided with nozzles that can be pressurized with a pressure medium. DE 37 34 965 A1 discloses a fluid-permeable object that allows the passage of a fluid through the object and consists of a porous ceramic structure comprising a plurality of hollow elements made of a ceramic material, which are connected or linked together in such a way as to form a framework in which a continuous capillary passage system is located, wherein the porous ceramic structure has a continuous space formed outside the framework and delimited by outer surfaces of the hollow elements, wherein a matrix material fills the continuous space formed outside the framework of the porous ceramic structure and forms a continuous matrix that interacts with the porous ceramic structure in such a way that a continuous or continuousA one-piece composite structure is provided, consisting of the ceramic material and the matrix material, wherein the continuous flow system is open at least in part of the free surfaces of the object and allows the fluid to flow through the object. DE 10 2010 015 558 A1 discloses a method for producing composite bodies from a permanently bonded, rigid, fluid-impermeable carrier body and a hard, porous molded body provided with a plurality of channels for the passage of fluids, comprising the following steps: providing salt powder and / or metal powder and binder powder as well as a rigid, fluid-impermeable carrier body; mixing the salt powder and / or metal powder and the binder powder into a powder mixture in a ratio of salt powder and / or metal powder to binder powder in the powder mixture ranging from 5 parts salt powder and / or metal powder to 1 part binder powder to 7 parts salt powder and / or metal powder to 1 part binder powder; loading the carrier body with the powder mixture.- Tempering the carrier body loaded with uncompressed powder mixture in an oven to a temperature at which the binder particles soften but do not flow off, forming binder bridges that connect adjacent salt and / or metal particles, and subsequently the binder hardens, creating a composite body of carrier body and molded body. JP 2008 - 231 576 A describes a bearing material consisting of a base metal and a fired and sintered porous metal layer on the surface of the base metal, wherein the sintered porous metal layer contains, among other things, particles of an inorganic material, in particular tin, nickel, phosphorus and copper, which in turn contain at least one of the following materials: graphite, boron nitride, graphite fluoride, calcium fluoride, aluminum oxide, silicon oxide and silicon carbide. JP H08-39343A discloses a band saw guide for a band saw machine with a lateral pair of saw blade guides to hold the saw blade in a vertical cutting position, and a lifting and lowering guide with a lifting and lowering body and a guide to prevent the saw blade from falling. The lifting and lowering guide is supported by a lifting and lowering frame on which the saw blade rests. The saw blade guide, which is attached to the lower end of the lifting and lowering body, has a saw blade clamping guide into which the rear part of the saw blade, guided in a vertical cutting position between the saw blade guides, can slide. When the saw blade is lowered for the working cut, it is separated from the saw blade and received on the top of a workpiece. The object of the invention is to provide a band guide for a saw band and a band saw, with which improved guidance of the saw band can be achieved. This problem is solved for the band guide with the features of claim 1. It is provided that the band guide has a guide body on which a first metallic guide layer and a second metallic guide layer are formed, wherein the first guide layer and the second guide layer are opposite each other and define a guide gap which is designed to receive a saw band section, wherein the first guide layer and the second guide layer are each designed as a microporous coating, and wherein a first air supply channel is assigned to the first guide layer to allow air to flow through the first guide layer, and wherein a second air supply channel is assigned to the second guide layer to allow air to flow through the second guide layer. The guide body is designed for mounting on the machine frame of a band saw and thus enables the transmission of forces from the saw blade to the first and second guide layers. These forces, which in turn are caused by the interaction of the saw blade with the workpiece being cut, must be transmitted via the blade guide to the machine frame of the band saw in order to prevent undesirable deformation of the saw blade, which would otherwise impair the cutting quality of the saw cut produced by the saw blade. In the aforementioned prior art, a contact-based force transmission between the saw blade and the guide elements, which are designed, for example, as guide rollers or as carbide sliding elements, is provided.This results in load-dependent wear phenomena on both the saw band and the guide elements due to the friction (rolling friction and / or sliding friction) between the high-speed saw band and the guide elements. In the band guide according to the invention, however, there is no direct contact between the saw blade and the first guide layer or the second guide layer. Instead, each of the two guide layers is designed to form an air cushion that extends between the respective guide layer and the saw blade, thereby enabling contactless power transmission between the saw blade and the guide body. To ensure the provision of a large and uniform air cushion, each of the two guide layers is designed as a microporous coating, which is designed to be permeated with compressed air.Thus, the compressed air supplied to the guide layer via the respective supply air duct can escape through a multitude of air channels formed in the microporous coating, thereby providing an air cushion with at least a largely homogeneous pressure distribution and a largely homogeneous mass flow distribution over the entire guide layer. Both the first guide layer and the second guide layer are made of a metallic material, which ensures high resilience for both guide layers even against possible frictional contacts with the saw band. The guide gap, bounded by the two guide layers, has a cross-section in a plane perpendicular to both the first and second guide layers that essentially corresponds to the cross-section of the saw blade being guided. A typical guide gap width, dependent on the saw blade thickness, ranges from 0.5 mm to 5 mm. A typical guide gap depth, dependent on the saw blade width, ranges from 10 mm to 100 mm. The microporous coating for the first and second guide layers is designed such that, when compressed air is applied to the first and second air supply channels at a working pressure between 1 bar and 8 bar, the air channels formed within the coating create an air cushion with the saw blade. These air cushions, located on both sides of the saw blade, prevent, and in particular eliminate, unwanted deformation of the saw blade and direct mechanical contact between the saw blade and the respective guide layer. This results in low-wear, and preferably wear-free, saw blade guidance, with wear prevention applying to both the saw blade and the first and second guide layers. Another advantage of using an air cushion to guide a saw blade is that the compressed air flow between the guide layer and the saw blade provides a cooling effect and removes chips. Chips and other contaminants adhering to the saw blade are likely to be prevented by the air cushion from entering the guide gap. Since the first and second guide layers are opposite each other, the first airflow direction exiting the first guide layer opposes the second airflow direction exiting the second guide layer. Thus, when a saw blade section is positioned in the guide slot of the guide body, an opposing airflow is achieved on the oppositely oriented side surfaces of the saw blade, thereby producing the desired stabilizing effect. Preferably, the first distance between the first guide layer and a first side surface of the saw blade, and the second distance between the second guide layer and a second side surface of the saw blade, are at least largely identical and are in an interval between 0.05 mm and 1 mm. It is advantageous if a first front face of the first guide layer is aligned parallel to a second front face of the second guide layer arranged opposite it. A parallel alignment of the second front face of the second guide layer with respect to the first front face of the first guide layer is advantageous at least when the saw blade has a rectangular cross-section in a cross-sectional plane that is oriented perpendicular to a direction of saw blade movement.In this case, the band guide and the saw blade can be coordinated such that both the first cross-section of the first air cushion formed between the first front surface of the first guide layer and the first side surface of the saw blade, and the second cross-section of the second air cushion formed between the second front surface of the second guide layer and the second side surface of the saw blade, are at least substantially rectangular. Provided that the respective microporous coatings, i.e., the first and second guide layers, are substantially homogeneous across their front surfaces, this ensures the desired uniform support for the saw blade. According to the invention, the guide body has a U-shaped profile, wherein the first guide layer is arranged on a first inner side of a first leg of the U-body, and wherein the second guide layer is formed on a second inner side of a second leg of the U-body, the second inner side being opposite the first inner side. The U-shaped profile of the guide body, taking into account the arrangement of the guide layers on the inner sides of the respective legs of the U-body, ensures an advantageous force flow within the guide body, since the reaction forces exerted by the saw blade on the guide layers are essentially opposite to each other and therefore largely cancel each other out within the guide body, so that only a small proportion of these reaction forces needs to be transferred from the blade guide to the machine frame. Furthermore, according to the invention, the first guide layer is embedded in a first recess of a first carrier plate, in particular made of metal, wherein the first carrier plate is attached to the first inner side, and the second guide layer is embedded in a second recess of a second carrier plate, in particular made of metal, wherein the second carrier plate is attached to the second inner side. The use of separately formed carrier plates simplifies the production of the guide layers, since the guide layers do not have to be inserted into the relatively narrow guide gap, but rather can be applied to the respective carrier plate independently of the guide body. It is preferred that the microporous coating is produced by a metal powder sintering process or a metal foaming process.For a preferably material-bonded connection between the microporous coating and the carrier plate, it is advantageous if the carrier plate is made of a metallic material, for example, steel. After the carrier plate has been coated with the guide layer, it can be attached to the inside of the respective leg of the guide body with the guide layer facing inwards. The microporous coating is embedded in a recess in the carrier plate, thus creating a sealing boundary for the microporous coating. This boundary prevents any of the compressed air introduced into the microporous coating from escaping in directions where it cannot provide guidance for the saw blade. The thickness of the microporous coating depends on the material selection and manufacturing technology used. Typical manufacturing processes for a microporous coating made from a metal material include foaming and sintering, which allow the microporous coating to be bonded to the substrate. Preferably, the microporous coating is a metal foam layer or a sintered metal layer. The pore size for air channels formed in the microporous coating can be specified with a mean diameter between 1 micrometer and 100 micrometers, expediently less than 50 micrometers. In a further development of the invention, an adjustment device is arranged between the second leg and the second support plate. This adjustment device is designed to adjust the spatial orientation of the first support plate, in particular its distance, relative to the first support plate. The adjustment device allows the cross-section of the guide gap to be adapted to the cross-section of the saw blade. Furthermore, the adjustment device compensates for geometric deviations that may occur in the saw blade, the guide layers, and the guide body, ensuring advantageous alignment of the two guide layers with respect to the saw blade and thus providing effective protection through the two air cushions. Preferably, the adjustment device can be operated both when the saw blade is stationary and when it is moving.For example, when the saw blade is stationary, a static adjustment for the spatial alignment of the second support plate relative to the second support plate can be made by, for instance, using a feeler gauge to determine the gap width between the respective guide layer and the saw blade at several points and, if necessary, adjusting the spatial alignment of the second support plate. Additionally or alternatively, when the saw blade is moving, a dynamic adjustment for the spatial alignment of the second support plate relative to the second support plate can be made. For this purpose, the gap width between the respective guide layer and the saw blade can be determined using a non-contact optical method or by other means. The adjustment device can, for example, be designed to set a distance between the first and second support plates.Alternatively, the adjustment device can also be designed to pivot the second support plate relative to the first support plate about two mutually perpendicular pivot axes, as well as to adjust the distance. This allows for the fulfillment of high parallelism requirements for the alignment of the opposing guide layers. The objective of the adjustment device is to ensure that the two air cushions formed between the first guide layer and the saw blade, and between the second guide layer and the saw blade, guarantee a symmetrical force transmission to the saw blade. In a further embodiment of the invention, the adjusting device comprises at least one adjusting screw fixed to the second support plate, which extends through the second leg with a guide section. A spring is arranged between the second support plate and the second leg for elastic support of the second support plate relative to the second leg, and an adjusting nut is screwed onto a threaded section of the adjusting screw projecting beyond the second leg. Preferably, the guide section of the adjusting screw and a recess in the second leg are adapted to each other such that the adjusting screw is guided linearly in the recess without significant radial play.Furthermore, a spring is arranged between the second support plate and the second leg, designed to provide elastic preload to the second support plate in the direction of the opposite first support plate. An adjusting nut is screwed onto a threaded section of the adjusting screw on the outer side of the second leg, allowing the axial position of the adjusting screw and thus the distance between the first and second support plates to be set. It is advantageous if the guide section of the adjusting screw passes through a stop that is adjustable along a longitudinal axis of the adjusting screw and is mounted in the second leg, against which the spring and the adjusting nut bear. The adjustable stop mounted in the second leg allows for decoupling between the axial position of the adjusting screw relative to the second leg and the spring preload. By way of example, the stop is designed as a threaded sleeve that is screwed with an external thread into a corresponding internal thread in the second leg, with the guide section of the adjusting screw passing through a bore formed centrally in the stop. Preferably, an end region of the stop facing away from the second support plate is designed as an actuation area that allows a torque to be applied to the stop to enable a screwing movement of the stop.For example, the actuation area may have pairs of parallel wrench flats that allow torque to be applied to the stop using an open-end wrench. The spring of the adjusting device rests against an axial end face of the stop facing the second support plate. The adjusting nut, screwed onto the adjusting screw, rests against an axial end face of the stop facing away from the second support plate. In an advantageous embodiment of the invention, the first supply air duct extends between a first front surface of the first support plate and a first rear surface of the first support plate, wherein several distribution grooves are provided in the first front surface, at least one distribution groove intersecting the first supply air duct, and wherein the first guide layer is bonded to the first front surface, in particular with a layer thickness of 0.5 mm to 5 mm, and covers the distribution grooves. The supply air duct can, for example, be provided as a bore, in particular as a blind hole, in the first support plate. Preferably, an axis of extension of the supply air duct is aligned parallel to the front and rear surfaces of the first support plate. The purpose of the distribution grooves is to pre-distribute the compressed air supplied via the supply air duct, which then flows through the first guide layer. For example, the distribution grooves can be arranged parallel to each other or in a grid pattern on the first front surface of the first carrier plate, and at least one, preferably several, of the distribution grooves intersects the first supply air duct to ensure a fluidic connection between the first supply air duct and the distribution grooves. For example, the first front surface of the first carrier plate is designed as a flat surface into which the distribution grooves are arranged, and the microporous coating is then applied to the front surface, forming a material-bonded connection with the front surface of the first carrier plate.In this process, the distribution grooves are also at least partially filled with the microporous coating, so that air channels running through the microporous coating can be supplied with compressed air from the distribution grooves. The second carrier plate is preferably identical in design to the first carrier plate. Preferably, the first guide layer and the second guide layer each have a width extent that corresponds to at least 70 percent of the saw blade width, and each has a length extent that is greater than its width extent. The saw blade width is the extent that the saw blade has in a spatial direction parallel to the direction of movement in which the workpiece is moved relative to the saw blade during the sawing process. In order to provide advantageous support for the saw blade, the first guide layer and the second guide layer cover at least 70 percent of the saw blade width.The length of the first guide layer and the second guide layer is aligned parallel to a direction of movement in which the saw band is moved during the sawing process and is chosen to be greater than the width. According to a further aspect, the object of the invention is solved by a band saw comprising a machine frame on which a first deflection roller is rotatably mounted about a first axis of rotation and on which a second deflection roller is rotatably mounted about a second axis of rotation, wherein the first axis of rotation and the second axis of rotation are aligned parallel to each other, as well as a drive device designed to introduce a rotational movement onto the first deflection roller, and a saw band which wraps around the first deflection roller and the second deflection roller in a portion thereof and which is guided between the first deflection roller and the second deflection roller in a band guide according to one of the preceding claims. An advantageous embodiment of a band guide is shown in the drawing. Here, Fig. 1 shows a perspective view of a band guide for a saw blade for use on a band saw (not shown), with a guide body and support plates mounted thereon; Fig. 2 shows a perspective view of the support plates according to Fig. 1; Fig. 3 shows a sectional front view of the band guide according to Fig. 1; Fig. 4 shows a sectional top view of the band guide according to Fig. 1; and Fig. 5 shows a sectional view of an adjustment device of the band guide according to Fig. 1. A band guide 1 shown in Fig. 1 serves for the contactless guidance of a saw blade 2, which forms part of a band saw (not shown in detail) with which sawing operations can be carried out on workpieces (not shown). The band guide 1 comprises a U-shaped profiled guide body 3, on which a first support plate 4 and a second support plate 5 are mounted. The spatial orientation of the first support plate 4, in particular its distance, relative to the second support plate 5 can be adjusted by means of adjusting devices 6. A first compressed air line 7, which is mostly concealed by the guide body 3, is associated with the first support plate 4. A second compressed air line 8 is associated with the second support plate 5. The saw blade 2 is moved in a sawing direction 21 relative to the blade guide 1 to perform a sawing operation. A workpiece (not shown) is moved transversely to the sawing direction 21 in a feed direction 22 to perform the sawing operation. The extent of the saw blade 2 in the sawing direction 21 is also referred to as the saw blade width. The extent of the saw blade 2 in a spatial direction that is oriented both transversely to the sawing direction 21 and transversely to the feed direction 22 is referred to as the saw blade thickness 23. A first front face 31 of the first support plate 4, hidden by the saw band 2 in the illustration of Fig. 1, faces the saw band 2, while a first back face 32 of the first support plate 4 is arranged opposite a first inner face 12 of a first U-shaped leg 10 of the guide body 3. For illustrative purposes only, the first support plate 4 is essentially cuboid in shape. A second front surface 33 of the second support plate 5 faces the saw band 2, a second back surface 33 of the second support plate 5 is arranged opposite a second inner surface 13 of a second U-shaped leg 11 of the guide body 3. For illustrative purposes only, the second support plate 5 is essentially cuboid in shape. The first front face 31 of the first support plate 4 and the second front face 33 of the second support plate 5 define a guide gap 9, which is shown in more detail in Fig. 3 and Fig. 4. Compressed air can be supplied to the first support plate 4 and the second support plate 5 via the first compressed air line 7 and the second compressed air line 8 in order to form air cushions in the guide gap 9 between the first front surface 31 and the saw band 2 and between the second front surface 33 and the saw band 2 respectively, with which a contactless force transmission between the saw band 2 and the support plates 4, 5 can be effected in order to ensure low-friction guidance of the saw band 2 during the sawing process. As can be seen in Figures 2, 3 to 4, the first support plate 4 is provided with a first microporous coating, also referred to as the first metallic guide layer 51. Furthermore, the second support plate 5 is provided with a second microporous coating, also referred to as the second metallic guide layer 52. The design of the first support plate 4 is described in detail below; a detailed description of the second support plate 5 is omitted, as it is identical to the first support plate 4. In the illustration of Fig. 2, the first metallic guide layer 51 is partially cut away to reveal the underlying geometry of the first support plate 4. For illustrative purposes, only the cut edge of the first metallic guide layer 51 is hatched to symbolize the foam-like microporous structure. In practice, the entire metallic guide layer 51, including the first front surface 31, exhibits the same structure. The first front surface 31 is provided with a first recess 35, which creates a first surface 36 that is, for illustrative purposes, flat and bordered by a circumferential first frame 37. First distribution grooves 38, arranged at equal intervals, are incorporated into the first surface 36 and are each fluidically connected to a first supply air duct 39, as can be seen in Fig. 3. The first supply air duct 39 is, for illustrative purposes, designed as a blind bore between the first front surface 31 and the first back surface 32, closed at its end by a first plug 40. A first bore axis 41 of the first supply air duct 39 is, for illustrative purposes, aligned parallel to the first front surface 31 and the first back surface 32. The first metallic guide layer 51 is inserted into the first recess 35 such that it is flush with a first end face 42 of the first frame 37. This ensures that the compressed air flows exiting the first support plate 4 through the air channels (not shown) of the first metallic guide layer 51, preferably with homogeneous volume flow and pressure distribution, strike the saw blade 2 at an angle of approximately 90 degrees, thus achieving a high efficiency for the desired guiding effect of the saw blade 2. As an example, it is provided that the first metallic guide layer 51 is introduced into the first recess 35 in a material-bonded manner using a sintering process. For illustrative purposes only, a first chamfer 43 is formed at opposite end regions of the first front face 31, extending approximately twice the width of the first frame 37. Between the two first chamfers 43, the first front face 31 of the first support plate 4 is, for illustrative purposes only, flat. The second support plate 5, which is identical to the first support plate 4, has a second recess 85, a second surface 86, a second frame 87, second distribution grooves 88 and a second supply air duct 89. As can be seen in Fig. 2, four second threaded bores 46 and a second connecting bore 47 are provided on the second rear side 34 of the second support plate 5, purely by way of example. Similarly, the first support plate 4 is provided with first threaded bores 44, which are shown in more detail in Fig. 5, and a first connecting bore 45, which is shown in Figs. 3 and 4. As can be seen in Fig. 3, the first compressed air line 7 is screwed directly into the first connection bore 45 of the first support plate 4. The second compressed air line 8 is screwed into an adapter piece 81, which is screwed into the second connection bore 47 via a threaded fitting 82 and passes through a stepped bore 16 that is formed in the second leg of the U-shape 11. The adapter piece 81 is designed to be linearly movable within the stepped bore 16. At an end region of the adapter piece 81 facing away from the threaded fitting 82, the adapter piece 81 is provided with an external thread 83 onto which an adjusting ring 84 is screwed, bearing against the second outer surface 15 of the second leg of the U-shape 11. To implement a rotation lock for the adapter piece 81, a guide rod 91 is fixed in the second support plate 5, which passes through the adapter piece 81 and prevents rotation of the adapter piece 81.By way of example, the guide body 3 is provided with threaded bores 53, 54, which enable the guide body 3 to be fixed to a machine frame of a band saw (not shown). As can be seen in Fig. 4, the first distribution grooves 38, which were cut into the first surface 36 of the first support plate 4 using a circular saw (not shown) and therefore have a circular segment-shaped profile in the sectional view of Fig. 4, each intersect the first supply air duct 39, so that each of the first distribution grooves 38 is in direct fluidic communication with the first supply air duct 39. In contrast to the illustration in Fig. 4, in the practical implementation of the first support plate 4, it may also be provided that the first metallic guide layer 51 partially or completely fills the respective first distribution grooves 38.For the homogeneous formation of an air cushion between the respective metallic guide layer 51, 52 and the saw band 2, it is only important that the air channels not shown are arranged as evenly as possible within the respective metallic guide layer 51, 52 and that the air channels not shown have cross-sections that lie within a specified cross-sectional interval. The detailed view in Fig. 5 shows that each of the adjustment devices 6 has an adjusting screw 61, which is screwed into the second threaded bore 46 of the second support plate 5 by means of a first threaded section 62. The adjusting screw 61 rests against the second rear side 34 of the second support plate 5 with an annular collar 65, so that the annular collar 65 serves as a depth stop for the adjusting screw 61. Adjacent to the annular collar 65 extends a guide section 63, which is shown to be cylindrical for illustrative purposes only, and to which a second threaded section 64 is attached. The guide section 63 and the second threaded section 64 each partially penetrate a sleeve-shaped stop 72, which is screwed into a threaded bore 17 formed in the second leg of the U 11 by means of an external thread 75. A spring 71, formed (purely by way of example) from several oppositely oriented disc springs, is supported between a first end face 73 of the stop 72 and the annular collar 65 of the adjusting screw 61. This spring 71 is designed to provide a preload for the adjusting screw 61 and the second support plate 5 coupled to it. An adjusting nut 66 rests against the second end face 74 of the stop 72, which is opposite the first end face 73. This nut allows adjustment of the distance between the annular collar 65 and the first end face 73 of the stop 72, and thus a spring preload for the spring 71. An axial change in position of the entire assembly, consisting of the second support plate 5, adjusting screw 61 with adjusting nut 66, spring 71, and stop 72, can be achieved by means of the actuating section 76 of the stop 72 (purely by way of example), in order to achieve a position shown in the figure.3 to set the indicated distance 23 between the two metallic guide layers 51 and 52, whereby this distance 23 is also referred to as the gap width of the guide gap 9.

Claims

Band guide (1) for a saw band (2), comprising a guide body (3) on which a first metallic guide layer (51) and a second metallic guide layer (52) are formed, wherein the first guide layer (51) and the second guide layer (52) are opposite each other and define a guide gap (9) which is designed to receive a saw band section, wherein the first guide layer (51) and the second guide layer (52) are each formed as a microporous coating, and wherein a first air supply channel (39) is assigned to the first guide layer (51) to allow air to flow through the first guide layer (51), and wherein a second air supply channel (89) is assigned to the second guide layer (52) to allow air to flow through the second guide layer (52), wherein the guide body (3) has a U-shaped profile.wherein the first guide layer (51) is arranged on a first inner side (12) of a first U-leg (10) of the guide body (3) and wherein the second guide layer (52) is formed on a second inner side (14) of a second U-leg (11) of the guide body (3), the second inner side (14) being arranged opposite the first inner side (12), characterized in that the first guide layer (51) is embedded in a first recess (35) of a first support plate (4) attached to the first inner side (12) and wherein the second guide layer (52) is embedded in a second recess (85) of a second support plate (5) attached to the second inner side (14). Belt guide (1) according to claim 1, characterized in that a first front side (31) of the first guide layer (51) is aligned parallel to an oppositely arranged, second front side (33) of the second guide layer (52). Belt guide (1) according to claim 1, characterized in that the first support plate (4) is made of metal and that the second support plate (5) is made of metal. Belt guide (1) according to claim 1, 2 or 3, characterized in that an adjustment device (6) is arranged between the second leg (11) and the second support plate (5), which is designed for adjusting a spatial orientation of the second support plate (5), in particular a distance, relative to the first support plate (4). Band guide (1) according to claim 4, characterized in that the adjusting device (6) has at least one adjusting screw (61) fixed to the second support plate (5), which extends through the second leg (11) with a guide section (63), wherein a spring (71) for elastic support of the second support plate (5) relative to the second leg (11) is arranged between the second support plate (5) and the second leg (11), and wherein an adjusting nut (66) is screwed onto a threaded section (64) of the adjusting screw (61) projecting beyond the second leg (11). Band guide (1) according to claim 5, characterized in that the guide section (63) of the adjusting screw (61) passes through a stop (72) adjustable along a longitudinal axis of the adjusting screw (61) in the second leg (11), against which the spring (71) and the adjusting nut (66) bear. Belt guide (1) according to one of the preceding claims, characterized in that the first supply air channel (39) extends between a first front (31) of the first carrier plate (4) and a first back (32) of the first carrier plate (4), wherein several distribution grooves (38) are provided in the first front (31), wherein at least one distribution groove (38) intersects the first supply air channel (39) and wherein the first guide layer (51) is bonded to the first front (31), in particular with a layer thickness of 0.5 mm to 5 mm, and covers the distribution grooves (38). Band guide (1) according to one of the preceding claims, characterized in that the first guide layer (51) and the second guide layer (52) each have a width extent which corresponds to at least 70 percent of a saw band width and that the first guide layer (51) and the second guide layer (52) each have a length extent which is greater than the width extent. Band saw with machine frame on which a first deflection roller is rotatably mounted about a first axis of rotation and on which a second deflection roller is rotatably mounted about a second axis of rotation, wherein the first axis of rotation and the second axis of rotation are aligned parallel to each other, as well as with a drive device designed for initiating a rotational movement on the first deflection roller, and with a saw band which wraps around the first deflection roller and the second deflection roller in a portion thereof and which is guided between the first deflection roller and the second deflection roller in a band guide according to one of the preceding claims.

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