Dismantling robot

Abstract

The invention relates to a demolition robot (1) comprising a robot arm (2) with a saw tool (3) with an exchangeable saw blade (5), wherein the saw tool comprises a rotatable spindle (4) with an end portion (4.1) and a saw blade with a hub (6), and the hub of the saw blade is arranged in a torque-transmitting connection (7) on the end portion (4.1) of the spindle in a releasable manner, wherein a release mechanism (30) for automatic exchange of the saw blade (5) is arranged on the robot arm.

Description

Technical Field

[0001] This invention relates to a remotely controllable demolition robot carrying a tool with replaceable parts, particularly a remotely controllable demolition robot including a saw tool with replaceable rotatable saw blades, and to a method for remotely and automatically changing saw blades on the saw tool. Background Technology

[0002] Remotely controlled demolition robots can be equipped with various types of demolition tools. For example, a demolition robot can carry a cutting saw tool, which has rotating blades or saw blades for cutting steel and other materials in various forms. The saw blades are consumable materials that wear down and must be replaced when they are depleted; therefore, the saw blades are usually replaced manually by the operator. However, in hazardous working environments where demolition robots are frequently used, it is highly inappropriate for operators to be near the robot's working area. This problem arises, for example, when the demolition robot is used in or around environments where there is a risk of radioactive radiation or hazardous gases. In environments where the level of radioactive radiation is so high that there is a risk of operator exposure or that the cumulative radiation dose the operator may be exposed to exceeds permissible levels, it is difficult to manually perform the replacement of the saw blades of the cutting saw tool in an effective manner. Summary of the Invention

[0003] The purpose of this invention is to provide a remotely controllable demolition robot that includes a cutting saw tool with replaceable blades. This demolition robot can reliably and automatically replace the rotatable saw blades without requiring manual operation by the operator, thereby improving safety and reducing the operator's working environment risks.

[0004] According to the invention, this objective is achieved by a demolition robot having the features and characteristics set forth in one aspect of the invention. This objective is also achieved by a method for remotely controlled automatic replacement of saw blades on a sawing tool associated with a demolition robot having the features and characteristics according to various aspects of the invention.

[0005] This invention means that worn parts associated with sawing tools carried by a remotely controlled demolition robot can be replaced with new parts in a remotely controlled, automatic, and reliable manner without the need for manual operation by the operator. Therefore, when the demolition robot is in operation, the operator does not have to be exposed to radioactive or hazardous gases, for example, in a hazardous working environment.

[0006] The following is a detailed description of the invention, from which further advantages will become apparent. Attached Figure Description

[0007] The following describes a demolition robot according to the present invention, in the accompanying drawings:

[0008] Figure 1 The illustration shows a demolition robot with a cutting saw according to the present invention.

[0009] Figures 2A to 2B An enlarged and simplified view of the robotic arm of a demolition robot with a cutting saw according to the present invention is shown. These figures show the cutting saw tool in a longitudinal sectional view. Detailed Implementation

[0010] Figure 1 A remotely controlled demolition robot 1 with a sawing tool 3 is shown, the sawing tool 3 being carried by the free end of a maneuverable robotic arm 2 associated with the demolition robot. An operator walks alongside the demolition robot and remotely controls the demolition robot via a radio link using a portable control cabinet equipped with the required joysticks and adjusters.

[0011] Figures 2A to 2B The illustration shows a robotic arm 2 of a demolition robot, which carries a cutting saw tool 3 with replaceable, rotatable saw blades 5. The saw blades are typically disc-shaped, rotationally symmetrical blades with hubs 6, which are releasably mounted on an end portion 4.1 associated with a rotatable spindle 4 of the cutting saw tool. The saw blades 5 with hubs 6 are releasably arranged on the spindle end portion 4.1 via torque transmission connections 7. A release mechanism 30 is arranged on the robotic arm 2 for remotely controlled automatic replacement of the saw blades. The release mechanism 30, including a remotely controllable hydraulic cylinder, is arranged adjacent to the spindle on the robotic arm and on the same side of the spindle relative to the saw blades.

[0012] The saw blade hub 6 has a first end connected to the saw blade 5, a hub flange 8 connected to the saw blade 5, and a second end 9 facing the spindle 4. The second hub end 9 has a truncated conical shape, having an outer conical envelope surface 9.1 and a planar end surface 9.2 in a radial plane, the outer conical envelope surface 9.1 having a decreasing diameter in the direction away from the saw blade 5.

[0013] Figure 2B The hub end 9 is shown to be configured as an annular end portion 9.10, the outer tapered enveloping surface 9.1 of which is configured to mate in form with the inner tapered clamping surface 4.10 associated with the spindle, and wherein the hub end surface 9.2 abuts against and mates in form with the inner support surface 4.18 associated with the spindle when the hub 6 is inserted into the spindle end portion 4.1 to obtain the correct radial and axial position of the saw blade on the spindle.

[0014] The saw blade hub has a central longitudinal opening 9.3 extending between the ends of the hub and having an inner limiting surface 9.4 with varying cross-section. An annular end portion 9.10 has a support surface 9.11 facing the axis of rotation and configured to abut against an intermediate member 12 associated with the blocking element 10, wherein the longitudinal opening 9.3 has a first inner diameter d1 along the support surface 9.11. The inner limiting surface 9.4 expands radially within the second hub end 9 to form an axially extending cavity 9.6 having a second inner diameter d2 greater than d1. Within the cavity 9.6, adjacent to the support surface 9.11, the saw blade hub has a tapered inner engagement surface 9.5 arranged internally, which is circumferential and configured to have a diameter that increases toward the saw blade. The engagement surface 9.5 of the hub is configured to engage with the blocking element 10 via a reverse engagement, such that the saw blade 5 can be releasably held on the spindle 4 under the influence of an applied tension force, generated, for example, by a drive spring 50, which clamps the hub of the saw blade against the end of the spindle in a fixed manner. The longitudinal opening 9.3 and the inner cavity 9.6 of the hub are arranged to receive the operating sleeve 15 and the blocking element 10 having a corresponding plurality of pawls 11, wherein the blocking element 10 is adapted to be inserted through the longitudinal opening 9.3 terminating at the second end 9 of the hub and extending into the cavity 9.6 to connect the hub of the saw blade to the spindle.

[0015] The cutting saw tool has a rotatable spindle 4 mounted in a bearing housing 20, which is arranged on a robotic arm. The spindle has a first end portion 4.1 projecting from the bearing housing and arranged adjacent to a hub 6. The first end portion 4.1 has a first impact surface 4.17 in a radial plane (i.e., a radial plane perpendicular to the axis of rotation of the spindle), the first impact surface 4.17 being arranged to abut against a receiving portion 4.5 and a flange 8 associated with the hub, the receiving portion 4.5 being configured as a recess located at the spindle end portion 4.1. The receiving portion 4.5 has an inner tapered clamping surface 4.10 connected to the impact surface 4.17 and an inner planar support surface 4.18 in the radial plane surrounding a central opening 4.15. The tapered clamping surface 4.10 of the spindle is configured to receive the saw blade and, in terms of shape, mates with the outer tapered envelope surface 9.1 associated with the hub to form a torque transmission connection 7 configured as a tapered clamping connection, which transmits the torque that occurs during the operation of the cutting saw tool from the spindle to the blade.

[0016] The spindle 4 includes at least two rotationally symmetric cavities 4.2 and 4.3, which are arranged internally and separated by a partition wall 4.8. The partition wall 4.8 includes a through central bore 4.20 arranged along the axis of rotation of the spindle, wherein a central opening 4.15 leads to the first cavity 4.2.

[0017] The first cavity 4.2 is intended to receive a sleeve-shaped blocking element 10 and has an inner limiting surface with varying shape and cross-section, the inner limiting surface corresponding in shape to the configuration of the blocking element so as to retain the blocking element 10 by rotational drive, the blocking element 10 being coupled in a spindle and capable of rotating with the spindle. The cavity includes a reduced-diameter channel 4.6 connected to the receiving portion 4.5. This channel is arranged to receive an intermediate piece 12 associated with the blocking element 10. The channel 4.6 is expanded into an inner compartment arranged to receive the rear end 13 of the blocking device. The inner compartment has an inner conical impact surface 4.4 intended to abut against the rear blocking device 13 of the blocking element. Adjacent to the partition wall 4.8, the first cavity 4.2 has a cylindrical compartment with a reduced cross-section compared to the inner compartment arranged to receive the rear end of the blocking element. This cylindrical compartment is configured to receive a compression spring 51 with an associated housing. The second cavity 4.3, which is closest to the second end of the main shaft, is a cylindrical shape with a uniform cross-section, in which a tension spring 50 connected to the tie rod 18 is arranged.

[0018] The spindle has a second end 4.11, which is connected to a transmission device, namely pulley 26. The pulley is connected to a drive motor (not shown) via a belt, such that torque from the drive motor is transmitted via the belt to pulley 26, which is mounted on the spindle 4, thereby rotating the spindle. The second end 4.11 of the spindle faces a remotely controllable hydraulic cylinder 25, which is arranged to activate the release of the saw blade when automatic blade changing is to be performed.

[0019] Figure 2B A sleeve-shaped blocking element 10 is shown, having a first end and a second annular end. The first end has a plurality of radially outwardly pointing pawls 11 arranged around the circumference, the pawls 11 being resiliently and radially actuated. The second annular end has an intermediate member 12 and at least one radially outwardly pointing rear blocking device 13, the intermediate member 12 connecting the first end and the second end. The blocking element 10 is incorporated into the spindle by being partially arranged within a first cavity 4.2 of the spindle.

[0020] The blocking element has an axially oriented central feed opening 14, and an operating device 18 connected to the operating sleeve 15 is inserted into the central feed opening 14, thereby causing the operating sleeve 15 to protrude from the feed opening in the longitudinal cavity of the hub toward the saw blade.

[0021] The rear blocking device 13 of the blocking element has an abutting surface that mates in shape with the inner conical impact surface 4.4 of the cavity disposed in the inner compartment of the cavity, and a portion of the intermediate part 12 of the blocking element is disposed in the channel 4.6. The first end of the blocking element carrying the pawl 11 protrudes from the central opening 4.15 of the spindle toward the receiving portion 4.5 of the spindle, such that the pawl 11 is positioned axially between the first impact surface 4.17 and the inner support surface 4.18 of the spindle. Figures 2A to 2B As shown, when the saw blade hub is inserted into the receiving portion 4.5 of the spindle, the blocking element is inserted through the longitudinal opening 9.3 of the hub into the enlarged inner cavity 9.6 at the second end 9 of the hub. The function of the blocking element 10 is to workably and reliably connect the saw blade hub to the spindle 4 in a radially and axially locked state, together with the operating sleeve 15, and to block and prevent the saw blade hub 6 from being released from the spindle. The radially outward-pointing pawl 11 is elastically and radially actuated and configured to engage and capture the inner tapered engagement surface of the hub. The operating sleeve is arranged to operate the blocking element 10 in the activated, locked state by releasably retaining the saw blade hub by radially outward pressing the pawl to engage the engagement surface 9.5 of the hub, and thereby releasably holding the saw blade hub 6 against the spindle.

[0022] Therefore, the blocking element 10 and the operating sleeve 15 apply a clamping force against the inner mating surface 9.5 of the hub. Under the influence of the tension force along the operating device 18 generated by, for example, the tension spring 50, this clamping force clamps the saw blade hub 6 against the spindle 4 in a releasable manner, thereby forming a tapered torque transmission clamping connection 7 between the inner tapered clamping surface 4.10 of the spindle and the outer tapered envelope surface 9.1 of the hub.

[0023] Under the influence of the tension spring 50 or the hydraulic cylinder 25, the saw blade hub 6 and the spindle 4 are connected by the torque transmission tapered clamping connection 7, together with the engagement surface 9.5 of the hub captured by the pawl 11, and by the reverse engagement of the hub end 9 around the blocking element 10, so that the hub of the saw blade is fixedly abutted against the spindle and thus the saw blade 5 is locked onto the spindle in a releasable manner.

[0024] Figures 2A to 2B The demolition robot also includes a release mechanism 30 for releasing or releasing a rotatable saw blade during a remotely controlled, automated blade replacement by an operator. The release mechanism includes a remotely controlled hydraulic cylinder 25 mounted on the robot arm 2, a manipulator 18 displaceably mounted on the spindle, and a manipulator sleeve 15. The hydraulic cylinder is connected to the manipulator sleeve 15 via the displaceable manipulator.

[0025] The operating device 18 includes an elongated pull rod connected to a hydraulic piston of a hydraulic cylinder, and extends along the axis of rotation of the spindle through the cavities 4.2, 4.3 of the spindle and through a drilled hole 4.20 in the partition wall, thereby connecting the end facing the saw blade to the operating sleeve 15. The operating device is preferably inserted into and connected to the operating sleeve through the central opening 15.4. The operating device 18 is displaceably housed in the spindle along the axis of rotation to enable automatic saw blade changing. A tension spring 50, arranged in the second cavity 4.3 of the spindle, is connected to the operating device to apply tension to the operating device 18 and the operating sleeve 15, thereby maintaining the torque transmission tapered clamping connection 7 during operation.

[0026] Figures 2A to 2B It is also shown that the end 4.1 of the spindle is arranged coaxially with the hub 6, the end 9 of the saw blade, the blocking element 10, the operating sleeve 15, and the operating device, whereby the blocking element is also arranged coaxially around the operating sleeve 15, such that the blocking element 10 is arranged between the operating sleeve and the inner limiting surface 9.4 of the hub. This results in a compact and reliable release mechanism.

[0027] Figures 2A to 2B As shown, the operating sleeve 15 is arranged in a blocking element located within the cavity of the spindle and has a first end 15.1, a second end 15.2, and an intermediate member 15.3. The first end 15.1 protrudes toward the saw blade in a longitudinal opening 9.3 of the hub. The second end 15.2 is coaxially arranged in a feed opening 14 of the blocking element and is slidably displaceable within this feed opening 14. The second end 15.2 is coupled to the operating device 18. The intermediate member 15.3 connects the first and second ends of the operating sleeve. The operating sleeve has a longitudinal central opening 15.4 between its ends for receiving the operating device 18. The operating sleeve is cylindrical with a varying outer cross-section, whereby the first end 15.1 has a larger diameter than the second end 15.2. The outer diameter of the first end is smaller than the inner diameter d1 of the hub, allowing the operating sleeve to move out through the longitudinal opening 9.3 of the hub to retrieve unused saw blades.

[0028] The intermediate part 15.3 of the operating sleeve is constructed with an arched comb-like surface 16, which is arranged circumferentially on the outside. The diameter of the comb-like surface 16 increases towards the saw blade, and the comb-like surface 16 extends along the first end into a straight cylindrical surface. The operating sleeve is displaceably received within the blocking element 10 and is displaceable through the longitudinal opening 9.3 of the hub. Through the longitudinal opening 9.3, the operating sleeve can be in an engaged state, a locked state, thereby releasably locking the saw blade hub onto the spindle, or in a disengaged released state, thereby releasing the saw blade hub from the spindle.

[0029] The comb-like surface 16 is arranged such that when the operating sleeve is moved toward the spindle 4 to the first state, i.e., the locked state, under the influence of the tension force from the tension spring 50, the operating sleeve can operate or press the pawls to move radially outward and lock them against the inner engagement surface 9.5 of the hub. In the locked state, the comb-like surface 16 effectively acts to prevent the radially resilient pawls 11 from moving radially inward toward the axis of rotation. By remotely activating the release mechanism and hydraulic cylinder, the operating sleeve 15 is moved forward toward the saw blade 5 or pressed by the hydraulic cylinder through the blocking element 10 and the saw blade hub 6 to present the second state, i.e., the released state. Thus, the pawls 11 of the blocking element are released from the engagement surface 9.5, and the resilient pawls are disengaged radially toward the axis of rotation, thereby making the saw blade hub 6 releasable and detached from the spindle 4.

[0030] The release mechanism 30 also includes a remotely controllable hydraulic cylinder 25, with its second end 4.11 adjacent to the spindle and disposed on a robot arm connected to the spindle. The hydraulic cylinder is connected to an operating sleeve 15 via an actuating device 18. The hydraulic cylinder has a hydraulic piston, which can be single-acting or double-acting. The hydraulic cylinder can be activated remotely by an operator to perform automatic saw blade replacement. When the release mechanism 30 is activated remotely, the hydraulic piston in the hydraulic cylinder 25 is displaced, wherein the actuating device 18 and the operating sleeve 15 are compressed to axially displace along the axis of rotation toward the saw blade, thereby performing automatic saw blade release, after which a new, unused saw blade is picked up and automatically attached to the spindle.

[0031] According to a method, remotely controlled automatic replacement of saw blades on a saw tool arranged on a robotic arm is performed, thereby activating a release mechanism 30 arranged on the robotic arm 2 of a demolition robot, and releasing the torque transmission connection 7 between the spindle and the saw blade hub via the release mechanism. Used saw blades 5 are released from the spindle 4 and fall via the release mechanism 30, and then unused saw blades 5' are picked up from a box 60 containing at least one unused saw blade 5' via the end portion 4.1 of the spindle. The picked-up saw blade 5' is attached to the end portion 4.1 of the spindle via the torque transmission connection 7 and releasably locked to the end portion 4.1 of the spindle.

[0032] For example, by remotely controlling and activating the hydraulic cylinder 25, the release mechanism 30 is activated, thereby acting on the operating sleeve 15 to release the torque transmission connection 7 by moving the operating sleeve 15 toward the saw blade 5 through the activated hydraulic cylinder.

[0033] When changing the saw blade, the actuating device 18 is pressed outward toward the hub 6 by means of the hydraulic cylinder 25. This causes the pawl 11 to disengage from the tapered engagement surface 9.5 in the hub and allows the blade 5 to fall out of the receiving portion of the spindle. The new blade 5' is picked up from the pre-assembled box 60 and locked, for example, by releasing the hydraulic pressure on the hydraulic cylinder to the can or by the action of the tension spring 50.

[0034] Under the influence of the tension spring 50 and / or the hydraulic cylinder 25, the picked-up unused saw blade 5′ is releasably locked to the end portion 4.1 of the spindle via the torque transmission connection 7 by engaging and forming a reverse engagement between the plurality of pawls 11 associated with the blocking element 10 and the tapered engagement surface 9.5 associated with the saw blade hub 6.

[0035] The picked-up unused saw blade 5′ is releasably connected and locked to the end portion 4.1 of the spindle via an actuating device 18. The actuating device 18, under the influence of a tension spring 50 and / or a hydraulic cylinder 25, displaces the actuating sleeve 15 in a direction away from the saw blade 5. The actuating sleeve 15 presses the blocking element against the mating surface 9.5 arranged internally in the saw blade hub, and connects the outer tapered envelope surface 9.1 associated with the hub and the inner tapered clamping surface 4.10 associated with the spindle, thereby clamping the hub against the spindle in a fixed manner.

Claims

1. A demolition robot (1) comprising a robot arm (2) having a saw tool (3) with replaceable saw blades (5), wherein, The saw tool includes a rotatable spindle (4) having an end portion (4.1) and a saw blade having a hub (6), wherein the hub of the saw blade is arranged on the end portion (4.1) of the spindle via a torque transmission connection (7), characterized in that a release mechanism (30) for automatically changing the saw blade (5) is arranged on the robot arm (2), wherein the release mechanism (30) includes an operating sleeve (15) and a remotely controllable hydraulic cylinder (25) arranged on the robot arm, the operating sleeve (15) being connected to the hydraulic cylinder via a movable operating device (18) arranged in the spindle (4), and the torque transmission connection (7) is configured as a tapered connection, the tapered connection including an outer tapered envelope surface (9.1) associated with the hub and an inner tapered clamping surface (4.10) associated with the spindle. The operating sleeve (15) is arranged to cooperate with the blocking element (10) integrated in the main shaft (4). The blocking element (10) has a first end with a plurality of radially outwardly pointing pawls (11) arranged around the circumference, and the pawls (11) are elastic and maneuverable in a radially outward direction and configured to engage with and capture the inner conical engagement surface (9.5) of the hub. In the locked state, the operating sleeve is arranged to operate the blocking element (10) along the operating device (18) under the influence of tension. In the locked state, the blocking element (10) is arranged to releasably retain the hub (6) of the saw blade by radially outward pressing the pawl (11) into engagement with the engagement surface (9.5) of the hub. In the released state, the hydraulic cylinder is activated, and the operating sleeve (15) is caused by the influence of the hydraulic cylinder to move forward or be pressed toward the saw blade (5) by the blocking element (10) and the hub (6) of the saw blade, wherein the blocking element is caused by the influence of the operating sleeve to release the hub (6), and the hub (6) of the saw blade is caused to be released from the end portion (4.1) of the spindle, wherein the saw blade is detached from the spindle (4).

2. The demolition robot according to claim 1, wherein, The blocking element (10) is inserted into the longitudinal opening (9.3) in the hub (6) of the saw blade.

3. The demolition robot according to claim 2, wherein, The conical engagement surface (9.5) of the hub of the saw blade is arranged internally to engage with the blocking element (10) by reverse engagement, wherein the saw blade (5) can be releasably held on the spindle (4).

4. The demolition robot according to claim 3, wherein, In the locked state, the pawl is pressed against the engagement surface (9.5) of the hub by the operating sleeve (15) under the influence of the tension force acting on the operating device (18), wherein a torque transmission conical clamping connection (7) is formed.

5. The demolition robot according to claim 4, wherein, In the locked state, the end portion (4.1) of the spindle is arranged coaxially with the hub (6) of the saw blade, wherein the hub (6) of the saw blade is arranged to receive the operating sleeve (15) and the blocking element (10) having an associated plurality of pawls (11), wherein the hub of the saw blade is arranged coaxially with and around the blocking element (10) and the operating sleeve (15), and the blocking element (10) is arranged between the hub and the operating sleeve.

6. The demolition robot according to claim 4 or 5, wherein, The operating sleeve (15) is disposed in the blocking element (10) in a displaceable manner, the blocking element (10) being located in an inner cavity disposed in the spindle, wherein the operating sleeve (15) includes a longitudinal central opening (15.4) for receiving the operating device (18) and is connected to the operating device (18), wherein the operating sleeve is displaceable through a feed opening (14) disposed in the blocking element and is displaceable through the longitudinal opening (9.3) of the hub toward the saw blade, wherein the operating sleeve is configured with an outer comb-like surface (16) arranged to engage with the pawl (11) of the blocking element.

7. The demolition robot according to claim 6, wherein, The outer comb-shaped surface (16) of the operating sleeve is arranged to press the pawl into a radially outward displacement and lock the pawl against the engagement surface (9.5) of the hub when the operating sleeve (15) is moved toward the spindle (4) to the locked state. In the released state, when the operating sleeve (15) is moved toward the saw blade (5), the outer comb-shaped surface is disengaged from the pawl (11), thereby releasing the pawl from the engagement surface (9.5), wherein the hub (6) of the saw blade is releaseable from the spindle (4).

8. The demolition robot according to claim 7, wherein, In the locked state, under the influence of the operating sleeve displaced by the tension spring (50) or the hydraulic cylinder (25), the saw blade (5) is releasably locked onto the spindle (4) by means of the torque transmission tapered clamping connection (7) formed between the hub (6) of the saw blade and the spindle (4), together with the engagement surface (9.5) of the hub captured by the pawl (11), by means of the end (9) of the hub engaging in reverse around the blocking element (10).

9. The demolition robot according to claim 8, wherein, In the released state, the hydraulic cylinder is activated, and the operating sleeve is displaced by the spindle (4) and the hub (6) of the saw blade under the influence of the hydraulic cylinder, wherein the pawl (11) of the blocking element is disengaged from engagement with the hub (6), and the saw blade is disengaged from the spindle.

10. The demolition robot according to claim 8, wherein, The tension spring (50) is arranged in the spindle and connected to the operating device (18), wherein the tension spring affects the operating device and the operating sleeve (15) by tension to maintain the torque transmission tapered clamping connection (7).

11. A method for remotely controlled automatic replacement of saw blades (5) on a saw tool (3) associated with a demolition robot (1) according to claim 1, wherein, The saw blade (5) is releasably arranged on the spindle associated with the saw tool via a torque transmission connection (7), wherein the method includes the following steps: - In the released state, the release mechanism (30) arranged on the robot arm of the demolition robot is activated by remote control of the hydraulic cylinder (25), thereby causing the hydraulic cylinder to move the operating sleeve (15) toward the saw blade; - The torque transmission connection (7) is released by the release mechanism (30) under the influence of the operating sleeve, causing the blocking element (10) to release from engagement with the hub (6), thereby causing the hub (6) of the saw blade to release from the end portion (4.1) of the spindle, so that the used saw blade is released and falls off the spindle. - Unused saw blades (5') are picked up from a box (60) containing at least one unused saw blade (5') by the spindle (4). - In the locked state, by causing the blocking element (10) coupled in the spindle (4) to be releasably engaged with the hub (6) of the saw blade by means of the operating sleeve which is displaced in a direction away from the saw blade by means of the tension spring (50) and / or the hydraulic cylinder (25), the picked-up unused saw blade (5′) is releasably connected to the end portion (4.1) of the spindle by means of the torque transmission connection (7).

12. The method according to claim 11, wherein, The blocking element (10) is arranged to engage with the hub (6) of the saw blade by reverse engagement.

13. The method according to claim 11 or 12, wherein, The operating sleeve (15) presses the blocking element (10) against the engagement surface (9.5) arranged inside the hub (6) of the saw blade, so that the hub is clamped against the end portion (4.1) of the spindle in a fixed manner by connecting the outer conical envelope surface (9.1) associated with the hub and the inner conical clamping surface (4.10) associated with the spindle, and forms a torque transmission conical clamping connection (7).

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