Mobile saw for solid, stone-like building materials, especially paving stones

Abstract

Mobile saw (S) for solid, stone-like building material bodies (T), especially paving stones, with - a worktop (U3) with a support surface (U31) for a building material body (T) to be sawn, - a linear guide (L) which is arranged above the support surface (U31) and aligned along it, - a saw unit (E) comprising a cutting disc (E3) and a main motor (E2) for driving the cutting disc (E3), and which is slidably held on the linear guide (L), - a feed drive (V), - with which the saw unit (E) can be moved along the linear guide (L) by motor drive, and - which is designed such that the feed rate applied to the saw unit (E) - is reduced with increasing load on the cutting disc (E3) during a sawing process, and / or - is increased with decreasing load on the cutting disc (E3) during a sawing process, - a clamping device (K) for clamping the building material body (T) onto the support surface (U31), and - a protective hood (H) which, above the support surface (U31), limits a working area (R) around the linear guide (L), saw unit (E) and feed drive (V).

Description

[0001] The invention relates to a mobile saw for solid, stone-like building material bodies, in particular paving stones.

[0002] Such a saw is known by way of example from DE 20 2017 100 769 U1. This saw has a cutting head with a cutting disc and a drive motor, a frame with a tray for holding a coolant, a cutting table movable on the tray and a coolant supply to the cutting disc.

[0003] To perform a sawing operation with such a saw, an operator places and aligns the material to be cut on the cutting table and then manually pushes the cutting table under the rotating cutting disc. Throughout the entire sawing process, the operator must ensure that the material does not slip on the cutting table and must also adjust the speed of the manual feed of the cutting table, relying on their own judgment, to ensure that the load on the cutting disc is not excessively high. During this manual execution of the sawing process, the operator is undesirably exposed to the emissions generated, particularly dust and granular fragments, as well as a high level of noise.To reduce physical strain caused by such emissions, operators must independently use appropriate personal protective equipment. Furthermore, after sawing, it is necessary to clean and dry both the saw and the material being cut to remove contaminants associated with water use, particularly sludge. All of this is very time-consuming for the operator.

[0004] The invention is therefore based on the objective of demonstrating a saw that enables the sawing of solid, stone-like building material bodies with reduced effort for one person.

[0005] The problem is solved with the saw specified in claim 1. Advantageous further embodiments of the invention are specified in the dependent claims.

[0006] According to the invention, the mobile saw for solid, stone-like building materials, in particular paving stones, has a worktop with a support surface for a building material to be sawn. This material is placed on the support surface to carry out a sawing operation.

[0007] The saw according to the invention further comprises a linear guide which is arranged above the support surface and aligned along it. The linear guide is arranged above the support surface and spaced apart from it. The linear guide runs largely parallel to the support surface.

[0008] The saw according to the invention further comprises a sawing unit, which includes a cutting disc and a main motor for driving the cutting disc, and which is slidably mounted on the linear guide. The cutting disc is set in rotation by means of the main motor, thus generating a relative movement to the building material to be sawn, enabling a sawing operation. The cutting disc can either be held directly on the main motor, e.g., directly on the motor shaft, or coupled to the main motor via a device for transmitting motion and power, e.g., a gearbox or a belt drive. The sawing unit with the main motor and cutting disc is held on the linear guide and is slidable along it. This makes it possible to move the rotating cutting disc along the path defined by the linear guide during the sawing operation, thus performing a straight sawing operation on a building material.

[0009] The distance between the linear guide and the support surface, as well as the diameter of the cutting disc, are precisely matched to allow the cutting disc to fully penetrate the material and thus cut through it completely. For this purpose, the worktop may have a groove that runs along the cutting disc's path. The distance between the linear guide and the support surface can be dimensioned so that the outer edge of the cutting disc is positioned slightly below the support surface, causing the cutting disc to penetrate the worktop slightly. This facilitates complete cutting of the material and simultaneously reduces the risk of unwanted collisions between the worktop and the cutting disc.

[0010] The saw according to the invention further comprises a feed drive with which the saw unit can be moved along the linear guide by motor. The feed device thus enables independent movement of the saw unit and automated or autonomous execution of sawing operations. It is therefore no longer necessary for an operator to move the saw unit manually along the linear guide. This advantageously reduces the effort required from an operator when using a saw according to the invention.

[0011] According to the invention, the feed drive is designed such that the feed rate exerted on the saw unit is reduced with increasing load on the cutting disc during a sawing operation, and / or increased with decreasing load on the cutting disc during a sawing operation. During a sawing operation, loads act on the cutting disc. The extent of these loads is significantly influenced by the type and properties of the material being sawn, particularly its hardness, as well as its dimensions, the degree of wear of the cutting disc, and the feed rate exerted on the cutting disc by the feed drive. A high hardness and thickness of the material being sawn, a high degree of wear of the cutting disc, and a high feed rate all result in an increase in the load acting on the cutting disc during a sawing operation.

[0012] A high load on the cutting disc leads to heat generation due to friction between the disc and the workpiece, and thus to an increase in the disc's temperature. Particularly with cutting discs coated with diamond particles, this temperature increase results in rapid wear of the diamond particles and consequently, rapid wear of the cutting disc. Therefore, it is desirable that the cutting disc's temperature does not exceed a certain range during the sawing process.

[0013] To prevent this, it has been standard practice for decades with stone saws to supply water as a cooling medium. However, this increases the effort required to prepare and execute a sawing operation, as water must be provided as an additional operating medium and the continuous water supply must be monitored by an operator. Furthermore, the addition of water to a sawing operation causes significant contamination or sludge buildup on the saw and the material being cut. This results in undesirable additional work for the operator in cleaning and drying the saw and the material.

[0014] In order to reduce such undesirable effort for an operator when using a saw according to the invention, the feed drive of a saw according to the invention is designed in such a way that the feed speed exerted on the saw unit is reduced with increasing load on the cutting disc during a sawing process, and / or can be increased again with decreasing load on the cutting disc during a sawing process.

[0015] This can be achieved in particular by appropriately controlling the feed drive. The basis for such control can be, for example, the motor current of the main motor, which it draws to maintain a constant speed, or the motor current of the feed motor, which it draws to maintain a constant speed, or a supporting force or passive force acting on the feed drive during a sawing operation.

[0016] This type of feed drive operation offers several advantages. Firstly, it allows for temperature regulation of the cutting disc during sawing, thus reducing disc wear. This results in a significantly longer service life for the cutting disc, thereby reducing the effort required for its replacement.

[0017] Furthermore, this operating method regulates the load acting on the cutting disc during a sawing operation, thus preventing an undesirably high temperature increase of the cutting disc. This offers the particular advantage that an additional cooling medium, especially water, can be dispensed with. The exceptional effect is that so-called "dry cuts" can be performed on building materials without the risk of excessive wear on the cutting disc.

[0018] Furthermore, this achieves the advantageous effect that the saw automatically applies an ideal feed rate appropriate to each individual case during every sawing operation. Such a saw, so to speak, automatically adjusts the applied feed rate as needed. This is particularly advantageous when performing sawing operations on building materials with widely varying thicknesses. When sawing a relatively thick building material, such as a paving stone, the saw applies a relatively slow feed rate, and when sawing a relatively thin building material, such as a tile, a relatively fast feed rate.In this way, a saw according to the invention, equipped according to this advantageous embodiment, can always be operated with the most ideal and economical operating parameters possible, without requiring any presetting or adjustments by an operator. This significantly reduces the effort required by the operator when performing sawing operations.

[0019] The saw according to the invention further comprises a clamping device for securing the building material to the support surface. A clamping force is exerted on the building material by means of the clamping device, thus fixing it to the support surface. This reduces the risk of unwanted slippage of the building material due to passive forces occurring during the sawing process, and thus reduces the risk of an undesirable decrease in the accuracy of the cut made in the building material. Furthermore, it is no longer necessary for the operator to manually hold down the building material during the sawing process. This advantageously reduces the effort required by the operator when using a saw according to the invention.

[0020] The saw according to the invention further comprises a protective hood that, above the support surface, defines a working space around the linear guide, saw unit, and feed drive. The protective hood is a hollow body open on one side, which is placed over the work surface. Thus, the protective hood and the support surface of the work surface define an almost enclosed working space in which the components of the saw required for carrying out a sawing operation, in particular the linear guide, the saw unit with main motor and cutting disc, and the feed drive, as well as the building material to be sawn, are arranged. A sawing operation carried out with such a saw therefore takes place within an enclosed volume. Consequently, emissions that regularly occur during the sawing operation, in particular dust or granular fragments and a high noise level, remain as far as possible within the working space.The protective hood thus shields the environment from the emissions of the sawing process. This advantageously reduces the release of such emissions into the environment and simultaneously the physical strain on an operator of a saw according to the invention. In particular, this advantageously reduces the effort required by an operator to protect themselves from such emissions when using a saw according to the invention.

[0021] To perform a sawing operation on a solid, stone-like building material, in particular a paving stone, by an operator on a saw according to the invention, the building material is placed on the support surface and aligned so that the desired cutting line in the building material aligns with the displacement path of the cutting disc along the linear guide. The clamping device is then engaged with the building material, thus fixing it to the support surface. The protective hood is then closed to shield the working area of ​​the saw according to the invention from the environment and thus reduce the release of emissions from the sawing process into the environment. Subsequently, the sawing process is started by an operator by activating the main motor and the feed drive and is carried out automatically by the saw according to the invention without any additional effort on the part of the operator.This relieves the operator of the responsibility of carrying out or closely monitoring the sawing process, reduces their exposure to emissions, and allows them to perform other tasks while the sawing process is underway.

[0022] A saw according to the invention is particularly advantageous when designed as a mobile device for operation on a construction site. Such a saw can be loaded and transported to a construction site by one person with minimal effort, preferably manually, without the need for complex transport and / or lifting equipment, and operated there using the operating resources typically available on a construction site. This also reduces the effort required by the operator when using a saw according to the invention.

[0023] A saw designed according to the invention thus offers the particular advantage that sawing solid, stone-like building material bodies is possible with reduced effort for an operator.

[0024] In a further advantageous embodiment of the invention, the clamping device has a pivotable clamping bracket that is arranged above the support surface and can be pivoted down onto a building material body on the support surface and locked in this pivoted position. The force for clamping the building material body is thus applied downwards from above. This clamping force acts in the same direction as the weight of the building material body, so that it is held down on the support surface by both its own weight and the applied clamping force. This advantageously achieves a particularly secure fixation of the building material body. It is therefore unnecessary to provide complex fixing devices that exert a lateral clamping force on the building material body and require a higher clamping force to achieve the same clamping effect.This further reduces the effort required by an operator when using a saw according to the invention.

[0025] In the state where the clamping device is not engaged with the material, it is pivoted upwards away from the support surface. In this state, the support surface is freely accessible, so that an operator is not hindered by the clamping device when handling, positioning, and aligning a material. This further reduces the effort required by the operator when using a saw according to the invention.

[0026] In a further advantageous embodiment of the invention, the worktop has a continuous cutting slot into which the cutting disc is inserted, and the saw has a suction device for removing air from the working area with a suction nozzle located on the underside of the worktop below the cutting disc. The cutting slot is formed as a slot-shaped opening in the worktop that completely penetrates the thickness of the worktop. The outer edge of the cutting disc is inserted at least partially into the cutting slot without coming into contact with the worktop. This achieves the advantageous effect that a building material placed on the support surface can be reliably and completely cut through by the cutting disc without the risk of a collision between the cutting disc and the support surface.The cutting gap in the worktop follows a path that corresponds to the path of the cutting disc along the linear guide. This allows the cutting disc to move along the linear guide without the risk of collision between the cutting disc and the support surface.

[0027] The saw also advantageously features an extraction device for removing air from the working area via an extraction port. This port is arranged on the saw according to the invention such that its intake side is located on the underside of the worktable, ideally directly below the cutting disc. This makes it possible to extract air containing particles from the working area as close as possible to the point of their release by the rotating cutting disc through the cutting gap during sawing, before the particles can accumulate in the saw's working area. This advantageously enables particularly effective removal of particles from the working area. As a result, the physical strain on the operator and the effort required to clean the saw according to the invention are further reduced.

[0028] A particularly advantageous feature is the design of the extraction port at its free end, which is located away from the work area, such that a standard hose or nozzle of a conventional vacuum cleaner can be attached to this end. This allows for extraction using simple, widely available devices, eliminating the need for complex, specialized extraction equipment. This further reduces the operator's workload when using a saw according to the invention.

[0029] In a further advantageous embodiment of the invention, the main motor is mounted on the saw unit such that it is positioned between the linear guide and the support surface. The main motor for rotating the cutting disc is suspended in the area of ​​the underside of the saw unit. This lowers the center of gravity of the saw unit on the linear guide, improves the balance of the saw unit on the linear guide, and simultaneously improves the damping of unwanted vibrations during the sawing process. In this way, the risk of an undesirable decrease in the accuracy of the cut in the building material is advantageously reduced. This also advantageously reduces the effort required by the operator when using a saw according to the invention.

[0030] According to a further advantageous embodiment of the invention, the saw has a base frame that is positioned so that the support surface is approximately at the operator's hip height. The base frame serves as a statically supporting structure beneath the saw. The base frame can be separate from the saw, allowing the saw to be placed on the base frame, or it can be an integral part of the saw's supporting structure. The base frame allows the saw according to the invention to be placed on a surface.

[0031] The base advantageously has a height such that the saw's support surface is positioned approximately at the operator's hip height. This allows the operator to use a saw according to the invention and handle building materials without having to assume an awkward physical position. In this way, sawing operations can be performed in a particularly ergonomic and effortless manner. This further reduces the physical strain on the operator when using a saw according to the invention.

[0032] In a further advantageous embodiment of the invention, the saw is designed to operate with a supply voltage of 230V. The saw according to the invention can thus be operated with a widely used standard voltage. This makes the saw according to the invention advantageously versatile. In particular, it is not necessary to provide special higher voltages for the operation of a saw according to the invention. This further reduces the effort required by the operator when using a saw according to the invention.

[0033] The invention and further advantageous embodiments thereof are explained in more detail below with reference to the briefly mentioned figures. These figures show Fig. 1 an advantageous embodiment of a saw S according to the invention in a schematic front view, Fig. 2 the advantageous embodiment of a saw S according to the invention Fig. 1 in a schematic top view, Fig. 3 the advantageous embodiment of a saw S according to the invention Fig. 1 in a schematic side sectional view along the section axis X1 of Fig. 1, and Fig. 4 the advantageous embodiment of a saw S according to the invention Fig. 1 in a schematic rear view.

[0034] The advantageous embodiment of a saw S according to the invention is described in the Fig. 1, Fig. 2, Fig. 3 to Fig. 4. To improve recognizability, only schematic and technically simplified representations are shown.

[0035] According to the representation in Fig. Figure 1 shows that the saw S has a frame consisting of a table-like base U and an upper frame O mounted on it. The base U has a frame made of four frame struts arranged in a rectangle. Fig. In Figure 1, only the front frame member U2a is visible in perspective. In the subsequent figures, the second and third frame members U2b and U2c are visible. The fourth frame member U2d is obscured by perspective in the figures and is therefore not shown.

[0036] Four vertical feet are arranged at the corners of the frame struts, allowing the S saw to be placed on a surface. Fig. In Figure 1, only the first foot U1a and the fourth foot U1d are visible from this perspective. In subsequent figures, the second and third feet U1b and U1c are visible. Advantageously, the feet have a length such that the base advantageously has a height such that the support surface U31 is positioned approximately at the operator's hip height. For clarity, the feet are shown in foreshortened form in the figures. In further advantageous embodiments of the invention, the feet can also be significantly shortened, allowing a saw S according to the invention to be positioned as a table-top device at an elevated position. Furthermore, the length of the feet can also be telescopically adjustable.

[0037] The saw S has four wheels U4 on its base U. These are each held at the lower ends of the first, second, third and fourth feet U1a, U1b, U1c, U1d. This allows the saw S according to the invention to be easily moved by an operator on a surface.

[0038] According to the invention, the saw S has a worktop U3 with a support surface U31 for a building material body T to be sawn. The worktop U3 is placed on the frame struts U2a, U2b, U2c, U2d. The building material body T placed on the support surface U31 is shown by way of example as a paving stone.

[0039] The upper frame O is arranged above the worktop U3 and, in the advantageous embodiment of a saw S designed according to the invention, also has a frame made of four horizontal struts arranged in a rectangle. Fig. In Figure 1, only the front first horizontal strut O2a is visible in perspective. In the subsequent figures, the second, third, and fourth horizontal struts O2b, O2c, and O2d are visible. Four vertical supports are arranged at the corners of the horizontal struts, which support the upper frame O on the lower frame U. Fig. In Figure 1, only the first vertical support O1a and the fourth vertical support O1d are visible. In the subsequent figures, the second and third vertical supports O1b and O1c are visible.

[0040] According to the invention, the saw S further comprises a linear guide L, which is arranged above the support surface U31 and aligned approximately along it. This means that the direction of extension of the linear guide L corresponds approximately to the course of the support surface U31. It is particularly advantageous for the direction of extension of the linear guide L to run approximately parallel to the course of the support surface U31. In the advantageous embodiment of a saw S designed according to the invention, shown in the figures, the linear guide L is arranged on the upper frame O, with the linear guide L running along the first and third horizontal struts O2a, O2c of the upper frame.

[0041] The linear guide L has two parallel, spaced-apart guide rails L1a, L1b. In the representation of Fig. Figure 1 shows only the first guide rail L1a, which is arranged on the first horizontal strut O2a of the upper frame, visible from this perspective. The exact structure of the linear guide L is shown in the top view of Fig. 2 and the sectional view of Fig. 3 will be explained in more detail.

[0042] According to the invention, the saw S further comprises a saw unit E, which includes a cutting disc E3 and a main motor E2 for driving the cutting disc, and which is slidably mounted on the linear guide L. The cutting disc E3 is, in particular, a diamond cutting disc suitable for solid, stone-like building materials. Such a cutting disc has a rigid base body with high inherent stability and sharp cutting edges coated with diamond particles, and is thus particularly suitable for low-vibration and precise sawing operations on solid, stone-like building materials. The cutting disc E3 is set in rotation by a main motor E2 and, in the illustrated embodiment of a saw S according to the invention, is arranged directly on the motor shaft E21 of the main motor E2. The upper half of the cutting disc E3 is covered with a protective cover E4.The cutting disc E3 is positioned above the worktop U3 such that its outer edge extends into the worktop U3, below the support surface U31. For this purpose, the worktop U3 has a continuous cutting gap U32 into which the outer edge of the cutting disc E3 can plunge without coming into contact with the worktop U3. The cutting gap U32 is shown in the top view of [reference missing]. Fig. 2 particularly noticeable.

[0043] The saw unit E is displaceable along the linear guide L. The advantageous saw S, as shown in the figures and designed according to the invention, has a four-sided profile slide E1, over which the saw unit is displaceably arranged on the linear guide. The linear guide L runs through the profile slide E1. In the advantageous saw S, as shown in the figures and designed according to the invention, the main motor E2 is advantageously held on the saw unit E such that it is arranged between the linear guide L and the support surface U31. The main motor E2 is thus suspended from the underside of the profile slide E1. The further construction of the profile slide E1 and its arrangement on the linear guide L are shown in the top view of the figures. Fig. 2 and the sectional view of Fig. 3 will be explained in more detail.

[0044] According to the invention, the saw S further comprises a feed drive V with which the saw unit E can be moved along the linear guide L by motor. The construction of the feed drive V and its operation are illustrated by reference to the top view of Fig. 2 will be explained in more detail. To generate a motorized feed motion, the feed drive V has a feed motor V2, whose rotary motion is advantageously transmitted by means of a belt drive V3 with a belt V33. The feed motor V2 is held on the upper frame O by an angled mounting bracket V4.

[0045] The saw S also has a control unit M for controlling the sawing process, in particular the main motor E2 and the feed motor V2. In the advantageous saw S shown in the figures, designed according to the invention, the control unit M is located on the underside of the worktop U3 in the front region of the first frame strut U2a and the fourth foot U1d of the base U. The control unit S has, by way of example, a first switch M1a, which can be used to activate the main motor E2, and a second switch M1b, which can be used to activate the feed motor V2.

[0046] According to the invention, the feed drive V is designed such that the feed speed exerted on the saw unit E is reduced with increasing load on the cutting disc E3 during a sawing operation and / or, conversely, can be increased again with decreasing load on the cutting disc E3 during a sawing operation. In the advantageous embodiment of a saw S shown according to the invention, this is implemented such that the control unit M continuously determines the load condition of the saw S based on the motor current drawn by the main motor E2 to maintain the cutting disc E3 within a predetermined speed range and adjusts the feed speed exerted on the saw unit E accordingly. This means that if the current drawn by the main motor E2 increases, the control unit M detects an increasing load condition and continuously reduces the speed of the feed motor V2 accordingly.Conversely, in the opposite case, where the current drawn by the main motor E2 decreases, and the controller M thus detects a decreasing load, the speed of the feed motor V2 is continuously increased accordingly. In the sawing process depicted in the figures, using a paving stone as the building material T, this results, among other things, in the saw unit E moving along the linear guide L at a higher feed rate after activation of the main motor E2 and feed motor V2, since no load is yet acting on the cutting disc E3. As the cutting disc E3 impacts the paving stone T and continuously penetrates it, the current drawn by the main motor E2, and thus the load acting on the saw S, also increases continuously. Consequently, the feed rate is continuously reduced by the controller M.The highest load condition, and thus the lowest feed rate, is reached when the cutting disc E3 is completely immersed in the paving stone T. The saw unit E then continues to move at a reduced feed rate appropriate to the prevailing load condition until the cutting disc E3 begins to emerge from the other side of the paving stone T. During this process, the saw cross-section decreases continuously, so the load acting on the saw S decreases continuously. The motor current drawn by the main motor E2 then decreases, causing the feed rate to be continuously increased by the controller M until the cutting disc E3 has completely emerged from the paving stone T and thus no load is acting on the saw S. The saw unit E then continues to move at the increased feed rate until the end of the feed path provided by the linear guide L.This method allows for particularly fast and wear-reduced sawing processes, making them especially economical. Before the cutting disc enters the material, the saw unit is moved at high speed, reducing the time it takes to start up along the linear guide. During the sawing process, the control system continuously generates a reduced feed rate, individually adjusted to minimize wear on the cutting disc. After the cutting disc exits the material, the saw unit is again moved at high speed, reducing the time it takes to travel along the linear guide.

[0047] According to the invention, the saw S further comprises a clamping device K for clamping the building material body T onto the support surface U31. The clamping device K is advantageously designed as a pivotable clamping bracket K1, which is arranged above the support surface U31 and can be pivoted down onto the building material body T on the support surface U31. The clamping bracket K1 is pivotally held on one side by a pivot joint K3 on a support strut K2, which is anchored to the work surface U3. The clamping bracket K1 can thus be pivoted down onto the building material body T along the first pivot direction X4 and locked in this position, so that the building material body T is clamped onto the work surface U31. Locking in the pivoted position can be achieved, for example, by means of a toggle clamp. The exact design of the clamping bracket K1 and its precise positioning are described by reference to Fig. 2 will be explained in more detail.

[0048] According to the invention, the saw S further comprises a protective hood H, which, above the support surface U31, delimits a working space R at least around the linear guide L, saw unit E, and feed drive V. To improve the visibility of the components behind it, the protective hood H is represented symbolically in the figures by a thick, dashed line. In the advantageous embodiment of a saw S according to the invention shown, the protective hood H is designed as a five-sided hollow cuboid with approximately flat sides, the open underside of which is arranged on the work surface U3, so that the latter closes the hollow cuboid. The protective hood H thus forms an enclosed working space R in which at least the components of the saw necessary for a sawing operation, in particular the linear guide L, the saw unit E, the feed drive V, and also the clamping bracket K, are arranged. In the front view of Fig. Figure 1 shows the first side wall H1 on the left side of the saw S, the second side wall H2 on the right side of the saw S, and the top cover plate H5. The protective hood H shields the work area R from the environment. This reduces emissions into the environment that occur during sawing operations, particularly dust and noise. The protective hood H can be sealed dust- and / or airtight with the work surface U3. The protective hood H can be made of a rigid, thin material, particularly a sheet of metal, with an additional insulating layer, particularly sound insulation, on its inner side facing the work area, and transparent windows for the operator to see inside.Furthermore, the protective hood H can be either completely removable from the work surface, swivelled away from it and held on the saw, or have a closable access opening in a surface for handling the building material body by an operator.

[0049] The saw S also advantageously features an extraction device A for removing air from the work area. This device has an extraction port A1, which is located on the underside of the worktop U3 below the cutting disc E3. In the advantageous embodiment shown in the figures, the extraction port A1 is designed as a pipe section with a conically widening intake end located on the underside of the worktop U3. The extraction port A1 is positioned on the underside of the worktop U3 such that the intake end of the extraction port A1 is located as centrally as possible at the cutting gap U32 and as directly as possible below the lowest point of the cutting disc E3. The other free end of the extraction port A1, facing away from the worktop U3, is advantageously designed as a tubular connector, which is configured so that a nozzle or hose of a standard vacuum cleaner A3 can be attached to it.The vacuum cleaner A3 is represented symbolically in the figures by means of a box. The base U advantageously has a receptacle for the vacuum cleaner A3, so that it can be held on or placed on a saw S according to the invention.

[0050] According to the invention, the saw S is designed as a mobile saw, particularly for use on a construction site. For this purpose, the saw S has a frame that is as light and stable as possible, consisting of an upper frame O and a lower frame U, so that the saw S can be moved and put into operation manually by an operator without special aids. Furthermore, the saw S, in particular the control unit, the feed motor V2, and the main motor E2, is advantageously designed so that it can be operated with a generally available and standard supply voltage of 230V.

[0051] From above Fig. Figure 2 shows that the linear guide L on the saw S has two parallel, spaced-apart guide rails L1a and L1b, along which the saw unit E is guided. The first guide rail L1a is located on the first horizontal strut O2a of the upper frame O, and the second guide rail L1b is located on the third horizontal strut O2c of the upper frame O. The first and second guide rails L1a and L1b are parallel and spaced apart.

[0052] Furthermore, in the top view of Fig. 2. It is particularly evident on the saw S that the guide rails L1a and L1b are arranged on opposite sides of the saw unit E. The first guide rail L1a is located on the side of the saw unit E facing the cutting disc E3, and the second guide rail L1b is located on the opposite side of the saw unit E in the area of ​​the third horizontal strut O2c of the upper frame O. This maximizes the distance between the guide rails L1a and L1b.

[0053] In the advantageous saw S shown in the figures, designed according to the invention, the first and second guide rails L1a, L1b are designed as profile rails, advantageously with a specifically matched counterpart. A first carriage L2a is mounted on the first guide rail L1a and a second carriage L2b is mounted on the second guide rail L1b. The first and second carriages L2a, L2b are held on the four-sided profile slide E1 of the saw unit E. This is shown in the sectional view of Fig. 3 will be explained in more detail.

[0054] Furthermore, in the top view of Fig. Figure 2 shows that the feed drive V has a linear drive element V1, which is arranged approximately centrally between the first and second guide rails L1a, L1b and runs along them. In the advantageous saw S shown in the figures, designed according to the invention, the linear drive element V1 is advantageously designed as a threaded spindle V11, wherein the thread is Fig. 2 is shown schematically with diagonal lines.

[0055] The threaded spindle V11 is advantageously rotatably mounted at its ends on the second horizontal strut O2b and the fourth horizontal strut O2d of the upper frame O. A spindle nut V12 is arranged on the threaded spindle V11 and is advantageously held against rotation on the saw unit E.

[0056] Furthermore, in the top view of Fig. 2. It is particularly evident on the saw S that the clamping bracket K1 is composed of a first clamping profile K11 and a second clamping profile K12, each advantageously having an L-shaped cross-section. The lower legs of the clamping profiles K11 and K12, which extend horizontally along the support surface U31, are placed on the material body T to clamp it. The upper legs of the clamping profiles K11 and K12, which extend vertically, are held on the support strut K2. The clamping profiles K11 and K12 are arranged on opposite sides of the support strut K2 and are thus abutting each other. In this way, a gap K13 is formed between the clamping profiles K11 and K12. The clamping bracket K1 is advantageously arranged on the saw S such that the gap K13 is aligned with the path of the cutting disc E3 along the linear guide, and the cutting disc E3 thus enters the gap K13 during a sawing operation.This offers the particular advantage that both halves of the cut material T are held down by the clamping device K during and after the sawing process. This reduces the risk of the cut halves slipping unintentionally.

[0057] Furthermore, in the top view of Fig. 2 on the saw S the surfaces of the protective hood H, i.e. the first side wall H1, the second side wall H2, the back wall H3, the top plate H5 and the diagonally aligned front wall H4 are recognizable.

[0058] Furthermore, in the top view of Fig. 2. It is particularly noticeable on the saw S that the extraction nozzle A1 is located in the middle of the cutting gap U32 and at the lowest point of the cutting disc E3, i.e., in a vertical perspective, below the motor shaft E21.

[0059] Furthermore, in the top view of Fig. 2 on the saw S the four wheels U4 on the feet of the base U are particularly recognizable.

[0060] Finally, in the top view of Fig. 2 on the saw S it is particularly noticeable that the cutting gap U32 in the worktop U3 also runs in the same direction as the linear guide L, so that the cutting disc E3 is arranged in the cutting gap U32 in every position along the linear guide.

[0061] The in the Fig. 1, Fig. 2, Fig. 3 to Fig. The advantageous saw S shown in Figure 4, designed according to the invention, functions as follows: Before the start of a sawing process, the saw unit E is arranged on the linear guide L in a starting position in the area of ​​the first vertical support O1a. The building material to be sawn, in particular a paving stone T, is placed on the support surface U31 and aligned so that the desired cutting path is aligned with the feed direction of the cutting disc E3. The main motor E2 is then activated, causing the cutting disc E3, which is held on the motor shaft E21, to rotate. To initiate the feed movement of the saw unit E, the feed motor V2 is activated. The rotation of the feed motor V2 is transmitted via a drive wheel arranged on the motor shaft first to a belt V33 and then to an output wheel that is fixedly mounted on the threaded spindle V11.The rotation of the feed motor V2 is transferred to the threaded spindle V11, setting it into rotation. Since the spindle nut V12 is held rotationally fixed to the saw unit E1, the rotation of the threaded spindle V11 is converted via the thread into a longitudinal movement of the spindle nut V12, causing the spindle nut V12 to move axially along the threaded spindle V11. In this way, a uniform feed motion is applied to the saw unit E along the linear guide L, and a sawing operation is performed on the material T on the support surface U31. The feed motion of the saw unit E can be controlled by the controller M such that the saw unit E is automatically returned to its starting position after reaching a predefined reversal point on the linear guide L.

[0062] In the sectional view of Fig. 3 along the intersection axis X1 of Fig. The construction of the linear guide L and saw unit E is particularly evident in the side view of the saw S. The first guide rail L1a is arranged on the first horizontal strut O2a, and the second guide rail L1b, spaced apart from and running parallel to it, is arranged on the third horizontal strut O2c. It is particularly noticeable that the guide rails L1a and L1b are advantageously aligned such that the plane spanned by the guide rails L1a and L1b runs parallel to the support surface U31. Depending on the design of the saw unit, the plane spanned by the guide rails L1a and L1b can also be perpendicular to the support surface U31 or be tilted relative to it. The first carriage L2a is arranged on the first guide rail L1a, and the second carriage L2b is arranged on the second guide rail L1b. The carriages L2a and L2b are held on the inside of the upper profile section E11 of the profile slide E1.This profile also features a parallel lower profile section E12, which runs below the first and second guide rails L1a and L1b. The upper and lower profile sections E11 and E12 are connected to each other via lateral profile sections, so that the profile slide E1 is designed in the form of a hollow rectangular tube through which the linear guide L passes.

[0063] The first and second guide rails L1a, L1b are designed as profile rails, with grooves on their lateral flanks into which the first and second carriages L2a, L2b laterally engage. The carriages are thus secured against lifting off the profile rails, enabling the guide rails L1a, L1b to absorb forces directed vertically upwards. For clarity, the grooves in the flanks of the first and second guide rails L1a, L1b are not shown in the figures.

[0064] Furthermore, in Fig. 3 The linear drive element V1 of the feed drive V is particularly recognizable. The linear drive element V1 does not have to be arranged directly in the middle between the guide rails L1a, L2b or directly in the plane defined by them. In the advantageous embodiment of a saw S according to the invention shown in the figures, the linear drive element V1 is arranged slightly below the plane defined by the guide rails L1a, L2b.

[0065] In the representation of Fig. Figure 3 further shows that the threaded spindle V11 is driven via the belt drive V3 by means of the feed motor V2, which is held on the retaining bracket V4. Fig. 3 are drive wheel V31, which is located on the motor shaft of the feed motor V2, the driven wheel V32, which is fixed to the threaded spindle V12 and the belt V33 connecting the two wheels, which are clearly visible.

[0066] Furthermore, in Fig. 3. It is particularly evident that the main motor E2 for driving the cutting disc E3 is advantageously suspended from the lower profile section E12 of the profile slide E1 in such a way that the latter is arranged between the linear guide L and the support surface U31. The center of gravity of the saw unit E is thus arranged as low as possible below the linear guide L, resulting in particularly stable and smooth guidance of the saw unit E on the linear guide.

[0067] Furthermore, in the section view of Fig. 3 on the saw S it is particularly noticeable that the extraction nozzle A1 is located on the underside of the worktop3 U3 in the middle to the cutting gap U32 and also to the cutting disc E3.

[0068] Furthermore, in the section view of Fig. 3. It is particularly evident on the saw S that the front wall H4 of the protective hood H runs at an angle. In the advantageous embodiment of a saw S designed according to the invention, the entire front wall H4 is designed as a flap, pivotably held on the cover plate H5 and thus pivotable upwards along the second pivot direction X5, so that the working area R is accessible to an operator.

[0069] Finally, in Fig. 3. It is particularly evident that the disc guard E4 is held on the side of the profile slide E1 by means of ribs and that the cutting disc E4 engages in the cutting gap U32 in the worktop U3.

[0070] In Fig. Figure 4 shows an advantageous embodiment of a saw S designed according to the invention in a top view of its rear side during the execution of a sawing operation. The cutting disc E3 is set in rotation by means of the main motor E2, wherein the direction of rotation X3 of the cutting disc E3 is in Fig. 4 is symbolically represented by an arrow. The cutting disc E3 is engaged with the building material body T. The saw unit E is moved from its starting position by means of the feed drive V. Fig. 1 and Fig. 2 moved to a mean instantaneous position along the linear guide L, with the direction X2 of the feed movement symbolically represented by an arrow.

[0071] The extraction device A is operated such that a vacuum cleaner A3 is connected to the outer end of the extraction nozzle A1, through which air is drawn in. This results in an extraction flow A2 through the extraction nozzle A1, which is directed into Fig.4 is symbolically represented with an arrow. Reference symbol list S saw for solid, stone-like building material bodies U-shaped base U1a, U1b, U1c, U1d first, second, third, fourth foot U2a, U2b, U2c, U2d first, second, third, fourth frame strut U3 worktop U31 contact surface U32 cutting gap U4 Rad O Upper frame O1a, O1b, O1c, O1d first, second, third, fourth vertical support O2a, O2b, O2c, O2d first, second, third, fourth horizontal strut L linear guide L1a, L1b first, second guide rail, in particular profile rail L2a, L2b first, second carriage E saw unit E1 four-sided profile slide E11, E12 upper, lower profile piece E2 Main Engine E21 Motor shaft E3 cutting disc E4 Windscreen cover V feed drive V1 linear drive element, in particular threaded spindle drive V11 threaded spindle V12 spindle nut, twist-resistant V2 feed motor V3 belt drive V31 drive wheel V32 output gear V33 belt V4 retaining bracket T Building material body, especially paving stone M control M1a, M1b first, second switch K clamping device K1 swivel clamping bracket K11, K12 first, second clamping profile, especially L-shaped K13 Gap between clamping profiles K11, K12 K2 support strut K3 swivel joint H Protective cover H1, H2 first, second side wall H3 back panel H4 front panel, especially swiveling H5 Cover plate A suction device A1 extraction port A2 extraction flow A3 vacuum cleaner R workspace X1 first intersection axis X2 Feed direction X3 Rotation direction X4, X5 first, second swivel direction QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 20 2017 100 769 U1

[0002]

Claims

[1] Mobile saw (S) for solid, stone-like building material bodies (T), in particular paving stones, with - a worktop (U3) with a support surface (U31) for a building material body (T) to be sawn, - a linear guide (L) which is arranged above the support surface (U31) and aligned along it, - a saw unit (E) comprising a cutting disc (E3) and a main motor (E2) for driving the cutting disc (E3), and which is slidably held on the linear guide (L), - a feed drive (V), - with which the saw unit (E) can be moved along the linear guide (L) by motor drive, and - which is designed such that the feed rate applied to the saw unit (E) - is reduced with increasing load on the cutting disc (E3) during a sawing process, and / or - is increased with decreasing load on the cutting disc (E3) during a sawing process, - a clamping device (K) for clamping the building material body (T) onto the support surface (U31), and - a protective hood (H) which, above the support surface (U31), limits a working area (R) around the linear guide (L), saw unit (E) and feed drive (V). [2] Saw (S) according to claim 1, wherein the clamping device (K) has a pivotable clamping bracket (K1) which is arranged above the support surface (U31) and can be pivoted down onto a building material body (T) on the support surface (U31) and locked in this pivoted position. [3] Saw (S) according to claim 1 or 2, wherein - the worktop (U3) has a continuous cutting gap (U32) into which the cutting disc (E3) plunges, and wherein - the saw (S, S') has an extraction device (A) for removing air from the working space (R) with an extraction nozzle (A1) which is located on the underside of the worktop (U3) below the cutting disc (E3). [4] Saw (S) according to one of the preceding claims, wherein the main motor (E2) is held on the saw unit (E) such that it is arranged between the linear guide (L) and the support surface (U31). [5] Saw (S) according to one of the preceding claims, with a base (U) having a height such that the support surface (U31) is arranged approximately at hip height of an operator. [6] Saw (S) according to one of the preceding claims, designed to be operated with a supply voltage of 230V.

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