JP5678195B2 - Hand-held machine tool clamping device - Google Patents

Description

  The present invention relates to a hand-held machine tool clamping device, ie a clamping device used in a hand-held machine tool, comprising at least one clamping unit provided for clamping a tool to a spindle, a clamping unit from the spindle, and / or Alternatively, the present invention relates to a hand-held machine tool clamping device provided with at least one drop-off prevention unit for avoiding tool drop-off.

  Furthermore, the invention relates to a hand-held machine tool, in particular an angle grinding machine.

BACKGROUND ART A hand-held machine tool clamping device having a clamping unit provided for clamping a tool to a spindle is already known. Furthermore, this known hand-held machine tool clamping device has a clamping unit from the spindle and / or a drop-off preventing unit for avoiding the tool from falling off.

DISCLOSURE OF THE INVENTION According to a hand-held machine tool clamping device according to the present invention, a drop-off prevention unit causes at least partly a second relative movement between at least two clamping elements of a clamping unit during braking operation. It has at least one motion change unit provided for converting into relative motion.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the invention, a motion change unit is provided for generating a relative motion along the axial direction of at least one of the two clamping elements during the braking operation. It is formed as a stroke unit.

  According to an advantageous embodiment of the hand-held machine tool clamping device according to the invention, the stroke unit has at least one stroke element formed at least partly integrally with one of the two clamping elements.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the present invention, the stroke unit is formed in a slope shape.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the invention, the hand-held machine tool clamping device is provided with at least one provided to limit the relative movement of at least one of the two clamping elements. It has a contact element.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the invention, the stroke unit is formed as a cam transmission device, the cam transmission device comprising at least one stroke element formed as a control notch. And at least one control element of the cam transmission is at least partially engaged in the stroke element.

  According to an advantageous embodiment of the hand-held machine tool clamping device according to the invention, the control element is formed in the shape of a pin.

  According to an advantageous embodiment of the hand-held machine tool clamping device according to the invention, the control notch is arranged in one clamping element of the clamping unit.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the invention, the cam transmission is at least provided for preloading at least one clamping element of the clamping unit relative to the control element. It has one spring element.

  According to an advantageous aspect of the hand-held machine tool clamping device according to the invention, the control notch extends in a predetermined plane of the clamping element along the circumferential direction along an angular range smaller than 40 °. have.

  According to the hand-held machine tool according to the present invention, the hand-held machine tool fastening device according to the present invention is provided.

  The present invention is a hand-held machine tool clamping device comprising at least one clamping unit provided for clamping a tool to a spindle, and at least one clamping unit and / or a tool for avoiding falling off the spindle. The present invention relates to a hand-held machine tool clamping device provided with a drop-off prevention unit.

  According to the invention, a fall-off prevention unit is provided at least for converting at least partly a first relative movement between at least two clamping elements of the clamping unit into a second relative movement during braking operation. It is proposed to have one motion change unit. Here, the “clamping unit” means a unit that is provided in particular for clamping the tool to the spindle against the mounting flange in the axial direction. Advantageously, the clamping unit is screwed onto the spindle via a screw thread. However, it is also possible for the tool to be clamped to the spindle by the clamping unit being coupled by another coupling manner that would be advantageous to those skilled in the art. In this context, “provided” means in particular “specially equipped” and / or “specially designed”. Here, the “drop-off prevention unit” means a unit provided to prevent at least almost the disappearance of the fastening force of the fixed unit in the axial direction, particularly during braking operation, particularly an increase in fastening force acting on the tool from the fastening unit. It means a unit provided to make it. Here, a “motion changing unit” has in particular a predetermined motion mode, for example a mechanism that can convert rotation into another motion mode, for example translation, in particular a thread or another mechanism that may be advantageous to the person skilled in the art A unit is defined. Here, the term “braking operation” means that a spindle of a hand-held machine tool, in particular, a spindle of a hand-held machine tool is braked by a braking device, and this is advantageous, for example, for the inertial rotation of the spindle when power supply to the electric motor is interrupted Means at least the operation of a hand-held machine tool, in particular the operation of the spindle, which can be sufficiently prevented. During braking operation, the mass inertia moment of a tool, particularly a disk-shaped tool, causes a relative movement between the tool fixed to the spindle and a clamping unit provided for clamping the tool to the spindle. End up. This relative movement between the tool and the clamping unit reduces the clamping force of the clamping unit and thus causes the clamping unit and / or tool to fall off the spindle. With the hand-held machine tool clamping device according to the invention, such a drop-off of the clamping unit from the spindle and thus the disengagement of the tool from the spindle can be advantageously avoided.

  Furthermore, it is proposed that the movement changing unit is formed as a stroke unit provided for generating a relative movement along the axial direction of at least one of the two clamping elements during braking operation. Here, the “stroke unit” means a unit capable of generating movement of one element, in particular along one axis of the clamping unit, in particular along a straight section, in particular along the axis of rotation of the spindle. ing. Here, the “axial direction” means a direction along the central axis of the tightening unit. The tightening unit is at least substantially rotationally symmetrical about the central axis. The arrangement according to the invention advantageously makes it possible to generate an axial stroke of one clamping element.

  In an advantageous manner, the stroke unit has at least one stroke element formed at least partly in one piece with one of the two clamping elements. Here, “integral” is in particular connected and / or advantageous in material connection, for example by a welding process, an adhesive process, a fixing process by injection molding and / or another process that would be advantageous to the person skilled in the art. For example, in one piece, ie as a single piece, for example by production from one casting and / or by one-component injection molding or multi-component injection molding and preferably from a single material It means that This advantageously saves construction space, assembly effort and costs.

  Furthermore, it is proposed that the stroke unit is formed in a slope shape. Here, the “slope shape” has a slope defined mathematically along a predetermined section in the direction from the start point to the end point. It means a geometric shape with a difference. Advantageously, the stroke unit has at least one further stroke element. The other stroke element generates a second relative movement based on the first relative movement in cooperation with one of the stroke elements. The inclination of the stroke element is advantageously greater than the inclination of the thread of one tightening element of the tightening unit and the inclination of the thread of the spindle which can be screwed or unscrewed, ie screwed off Is set to the size of In this case, the inclination of the stroke element is in particular 100 to 150% of the inclination of the clamping element and the spindle thread, preferably 110 to 140% of the inclination of the clamping element and the spindle thread, particularly preferably the clamping element and This corresponds to 120 to 130% of the inclination of the spindle thread. In order to increase the friction within the thread of the fixing unit and the spindle compared to the friction between the stroke elements, a means of increased lubricity in the thread of the fixing unit and the spindle, for example rubber elements, spring elements, coating layers Etc. can be inserted. In an alternative embodiment of the drop-off prevention device according to the present invention, one stroke element of the stroke unit has a second stroke element for generating an axial stroke between the first transmission element and the second transmission element. It may be formed as a rolling element that rolls along a sloped travel element when the first transmission element rotates relative to the transmission element. The relative movement for generating and / or maintaining the clamping force during the braking operation can be simply achieved structurally.

  Advantageously, the fall-off prevention device according to the invention comprises at least one abutment element provided to limit the relative movement between the two clamping elements. Advantageously, this abutment element is formed integrally with one of the clamping elements. In this case, the other of the clamping elements has at least one recess provided for accommodating the abutment element. The aspect according to the invention advantageously limits the angular range in which the clamping elements can be rotated relative to one another. This angular range is set in particular below 25 °, preferably below 15 °, particularly preferably below 7 °.

  In an alternative embodiment of the hand-held machine tool clamping device according to the invention, the stroke unit is formed as a cam transmission device, the cam transmission device comprising at least one stroke element formed as a control notch. And at least one control element of the cam transmission is at least partially engaged in the stroke element. Here, the “cam transmission” is based on the movement of the first cam element, in particular the movement of the control element around one axis and in cooperation with the second cam element, in particular the control notch. Based on this, it means a mechanism for controlling a component that performs a movement set by the cooperation of both cam elements. Here, the “control notch” means a material removal portion with which the control element is engaged in order to generate movement. The control element and the control notch are particularly movable relative to each other. With the drop-off prevention device according to the invention, the guide of the control element in the control notch can be achieved structurally simply. Furthermore, it is advantageous to prevent the tool from falling off.

  Furthermore, it is proposed that the control element is formed in a pin shape. Here, “pin-shaped” means a geometrical shape that has at least approximately the main extension length, in particular the main extension length along the central axis. This geometric shape is formed rotationally symmetrically about the central axis. The main extension length is set to be at least the same size as the extension length, especially the diameter, of the geometric shape extending perpendicular to the main extension length. The control element is particularly preferably formed by a cylindrical pin. However, it is also possible for the control element to be formed in other shapes that would be advantageous to those skilled in the art. The main extension length of the control element extends at least substantially perpendicular to the central axis of the clamping unit and / or the rotational axis of the spindle in the assembled state. Here, the expression “substantially vertical” defines the direction of one direction relative to the reference direction. In this case, this direction and the reference direction form an angle of 90 °, especially in one plane, and the angle is in particular less than 8 °, preferably less than 5 °, particularly preferably 2 °. Has a maximum deviation of less than.

  However, the main extension length of the control element extends along another axis and / or direction that would be advantageous to the person skilled in the art, for example at least approximately parallel to the central axis of the clamping unit and / or the rotational axis of the spindle. It is also possible. When the main extension length extends parallel to the spindle axis of rotation, the pin-like control element is engaged in the control notch in which the sloped running path is arranged. It becomes possible to be. If the main extension length is oriented parallel to the rotational axis, the control notch extends at least in a plane extending substantially perpendicular to the central axis of the transmission unit and / or the rotational axis of the spindle. ing. The control element has a slip coating layer, in particular on the surface facing the control notch, and the sloped travel path also has a slip cover layer, so that there is a gap between the travel path and the control element. Less friction can be achieved. However, the spindle and the transmission element of the transmission unit, each of which is arranged on the spindle, in particular the transmission element connected in form connection to the spindle, each have a groove so that the control element forms an interface. It can also be formed as a rolling element inserted in the groove, in particular a ball. The control element is formed as a screw thread between the spindle and a transmission element arranged on this spindle, in particular directly contacting this spindle, so that one transmission element of the transmission unit along the axis of rotation of the spindle It is also possible to generate a relative movement between the spindle and the spindle. Other configurations of the control element and / or the interface between the spindle and the transmission element are possible which would be advantageous to the person skilled in the art. Due to the pin-like configuration of the control element, a stable control element can advantageously be achieved. Furthermore, a position fixing function, for example, in particular to fix the position of the transmission unit in the axial direction on the spindle and / or to fix the position relative to the rotation, can be achieved structurally easily.

  Advantageously, a control notch is arranged in one clamping element of the clamping unit. The control notch is particularly preferably arranged in the clamping element. In this case, the control notch is formed in particular by a groove. Advantageously, the clamping element has a material thickness in the area of the control notch that is less than the area of the clamping element adjacent to the control notch, in particular a material thickness of 0 mm. However, it is also possible for the outer surface of the clamping element to have at least two ribs on which the control element engages at least partially. These at least two ribs may extend in the direction of the control element, at least approximately vertically, in particular starting from the outer surface, so that at least two ribs can form a guide for the control element. The control element advantageously extends at least partially through the clamping element in the area of the control notch. Here, the concept of “extending through” is in particular along the direction in which the control element extends at least substantially perpendicular to the central axis of the clamping element and at least substantially perpendicular to the central axis. It means that the main extension length is larger than the extension length of the control notch. Advantageously, a secure connection between the control element and the control notch and clamping element can be achieved.

  Advantageously, the cam transmission has at least one spring element provided for preloading at least one clamping element of the clamping unit relative to the control element. Here, the “spring element” means an element that can be elastically deformed particularly under a load. This element can store potential energy, and after relaxation, the stored potential energy can automatically return to the shape that the element had before the load was applied. The spring elements are preferably formed as tension springs and compression springs. However, it is also possible that the spring element is formed by another element that would be advantageous to the person skilled in the art. Advantageously, a structurally simple return of the cam transmission and / or the transmission element relative to the spindle to the starting position can be achieved.

  Furthermore, it is proposed that the control notch has an extending length along an angular range of less than 40 ° along the circumferential direction on a predetermined surface of the clamping element. Advantageously, the control notch is arranged on the circumferential surface of the clamping element along an angular range of less than 30 °, particularly preferably along an angular range of less than 20 °. The peripheral surface preferably extends concentrically about the central axis of the clamping unit. Particularly preferably, the circumferential surface is at least partly formed by the circumferential wall surface of the hollow cylindrical spindle receiving area of the clamping element. The circumferential direction advantageously extends in a plane that extends at least partially perpendicular to the central axis of the clamping unit. Particularly preferably, the control notch has a mathematically defined inclination in the axial direction along the circumferential direction. The inclination of the control notch is in particular 100 to 150% of the inclination of the thread between the clamping nut and the spindle, preferably 110 to 140% of the inclination of the thread between the clamping nut and the spindle, particularly preferably. Corresponds to 120 to 130% of the inclination of the thread between the clamping nut and the spindle. Advantageously, a compact drop-off prevention device can be achieved.

  Furthermore, the invention relates to a hand-held machine tool, in particular an angle grinding machine. This hand-held machine tool includes the hand-held machine tool fastening device according to the present invention. Advantageously, the falling off of the tool from the spindle of the hand-held machine tool can be avoided.

  Further advantages are apparent from the following illustration. In the drawings, a plurality of embodiments of the present invention are shown. The drawings, specification, and claims include numerous features in combination. Those skilled in the art may advantageously consider these features individually or combine them in other advantageous combinations.

It is the schematic of the handheld machine tool provided with the handheld machine tool clamping apparatus which concerns on this invention. It is a figure which shows roughly the detail of the spindle by which the hand-held machine tool clamping apparatus which concerns on this invention of the hand-held machine tool shown in FIG. 1 is arrange | positioned. It is a figure which shows schematically the detail of the side opposite to a tool in the assembled state of the hand-held machine tool clamping device according to the present invention. It is a figure which shows schematically the detail of the side orient | assigned to the tool in the assembled state of the hand-held type machine tool clamping device which concerns on this invention. FIG. 5 is a detailed perspective view of the hand-held machine tool clamping device according to the present invention in an open state including a cross section taken along line VV in FIG. 4. FIG. 5 is another perspective detail view of the hand-held machine tool clamping device according to the present invention in an open state including a cross section taken along line VV in FIG. 4. FIG. 5 is a perspective detail view of an alternative hand-held machine tool clamping device according to the present invention in an open state including a similar cross-section along line VV in FIG. 4. It is a schematic sectional drawing along the axis of rotation of the spindle of the hand-held machine tool device in the present invention. It is a schematic sectional view along the axis of rotation of the spindle of the hand-held machine tool device in the present invention after the hand-held machine tool is switched off. It is a figure which shows roughly the detail of the control notch of the cam transmission apparatus of a hand-held machine tool clamping device.

Description of Embodiments FIG. 1 schematically shows a hand-held machine tool 62a formed as an angle grinding machine 60a. The hand-held machine tool 62a includes the hand-held machine tool fastening device 10a according to the present invention. The angle grinding machine 60a includes a protective hood unit 64a, a hand-held machine tool housing 66a, and a main hand grip 68a. The main hand grip 68a extends in the direction of the main extending direction 72a of the angle grinding machine 60a on the side 70a opposite to the tool 14a. The hand-held machine tool housing 66a includes a motor housing 74a for housing an electric motor (not shown) and a transmission device housing 76a for supporting a transmission device (not shown). An auxiliary hand grip 78a in the angle grinding machine 60a is disposed in the transmission housing 76a. The auxiliary handgrip 78a extends in the lateral direction with respect to the main extending direction 72a of the angle grinding machine 60a.

  FIG. 2 schematically shows details of the spindle 16a on which the hand-held machine tool clamping device 10a of the hand-held machine tool 62a formed as an angle grinding machine 60a is arranged. The spindle 16a extends from a transmission housing 76a (not shown here) perpendicular to the main extending direction 72a. The hand-held machine tool fastening device 10a has a fastening unit 12a provided for fastening a disk-shaped tool 14a to a spindle 16a. The spindle 16a has two flat processed portions 82a on the outer peripheral surface for attaching the attachment flange 80a. Both flattened portions 82a are arranged on opposite sides in the diametrical direction, and thus form a two-surface cut portion 84a. In FIG. 2, only one of the flattened portions 82a is shown. The outer peripheral surface of the spindle 16a is disposed on a plane extending perpendicular to the rotation axis 86a of the spindle 16a. However, the spindle 16a is conically formed in the mounting range relative to the mounting flange 80a, and the mounting flange 80a has a mounting opening corresponding to the conical configuration, so that the spindle in the assembled state A conical fit can also be formed between 16a and mounting flange 80a. The spindle 16a is driven to rotate about a rotation axis 86a by a transmission device (not shown) and an electric motor (not shown) of the angle grinding machine 60a. During the operation of the angle grinding machine 60a, the spindle 16a is driven to rotate clockwise as viewed from the angle grinding machine 60a. At that time, the hand-held machine tool fastening device 10a is also driven to rotate clockwise in the assembled state.

  The tightening unit 12a of the hand-held machine tool tightening device 10a includes a first tightening element 22a and a second tightening element 24a that can move relative to the first tightening element 22a ( (See FIG. 5). The first tightening element 22a is formed in a disk shape. Further, the first tightening element 22a has a contact surface 92a. The contact surface 92a is in contact with the tool 14a in an assembled state. The tool 14a is inserted into the spindle 16a along the axial direction 28a at the center opening at the time of assembly, and then comes into contact with the mounting flange 80a. The tightening unit 12a is then screwed onto the thread 90a of the spindle 16a by the female thread 88a of the second tightening element 24a, after which the contact surface 92a of the first tightening element 22a contacts the tool 14a. Therefore, the tool 14a is fastened to the mounting flange 80a with respect to the spindle 16a by the fastening unit 12a. The abutting surface 92a of the first clamping element 22a and the surface of the tool 14a that contacts the abutting surface 92a may have an adhesion coating layer (not shown), whereby the first clamping element Friction between the contact surface 92a of the element 22a and the surface of the tool 14a that contacts the contact surface 92a is increased. However, it is also possible for the contact surface 92a and the surface of the tool 14a that contacts the contact surface 92a to have a corresponding beveled geometric shape that engages inside and outside. Other means and configurations of abrasiveness that would be advantageous to those skilled in the art are also possible for the abutment surface 92a and the surface of the tool 14a that contacts the abutment surface 92a.

  By tightening the tool 14a against the spindle 16a between the tightening unit 12a and the mounting flange 80a, torque is transmitted from the spindle 16a to the tool 14a. The tool 14a is rotationally driven in the clockwise direction when viewed from the angle grinding machine 60a during the operation of the angle grinding machine 60a. During the operation of the angle grinding machine 60a, the tightening force of the tightening unit 12a for tightening the tool 14a is based on the friction between the tightening unit 12a and the surface of the tool 14a that contacts the contact surface 92a. Maintained. The tightening unit 12a has two rotational force transmission holes 176a and 178a on a surface 174a opposite to the abutting surface 92a. A pin wrench (crab wrench) for generating a tightening torque and / or a loosening torque can be engaged in the rotational force transmission holes 176a and 178a. Each of the rotational force transmission holes 176a and 178a has one central axis. This central axis extends substantially parallel to at least the rotational axis 86a in the assembled state of the hand-held machine tool clamping device 10a.

  The angle grinding machine 60a has a braking device (not shown) for avoiding inertial rotation of the spindle 16a due to, for example, interruption of power supply when the angle grinding machine 60a is switched off. During the switch-off operation, the angle grinding machine 60a is switched to the braking operation, and the spindle 16a is braked by the braking device. During the braking operation, the tool 14a is continuously moved in the clockwise direction based on the mass inertia or is continuously moved around the rotation axis 86a of the spindle 16a, whereby the tool 14a, the spindle 16a and the clamping unit are moved. A torque difference is generated between the motor 12a and 12a. This torque difference causes a relative movement between the tool 14a and the tightening unit 12a. Based on the friction between the clamping unit 12a and the inertial tool 14a, the clamping unit 12a is rotated together with the tool 14a in a direction opposite to the rotational direction formed during the operation of the angle grinding machine 60a. As a result, the thread preload formed by the pitch of the female thread 88a of the second tightening element 24a and the pitch of the thread 90a of the spindle 16a is eliminated. As a result, the tightening force of the tightening unit 12a is reduced, and the tightening unit 12a falls off the spindle 16a together with the tool 14a.

  In order to avoid the dropout of the tightening unit 12a and / or the tool 14a, the hand-held machine tool fastening device 10a has a dropout prevention unit 18a. The dropout prevention unit 18a has a motion change unit 20a. This movement changing unit 20a is provided for at least partially converting the first relative movement between the first clamping element 22a and the second clamping element 24a of the clamping unit 12a into a second relative movement. (See FIG. 5). The first relative movement between the first tightening element 22a and the second tightening element 24a is rotation about the rotation axis 86a. The second relative movement between the first clamping element 22a and the second clamping element 24a is translation along the axial direction 28a. The rotation between the first tightening element 22a and the second tightening element 24a is generated from the torque difference between the tool 14a and the tightening unit 12a during the braking operation. The tool 14a rotates the first clamping element 22a together by friction formed between the tool 14a and the contact surface 92a of the first clamping element 22a. The second clamping element 24a is coupled to the spindle 16a by an internal thread 88a. The first tightening element 22a is movably supported in a second tightening element 24a formed in a pot shape. The first tightening element 22a is supported in the second tightening element 24a so as to be movable along the circumferential direction 58a and the axial direction 28a.

  The motion change unit 20a is formed as a stroke unit 26a. This stroke unit 26a is provided for moving the first clamping element 22a in the axial direction 28a based on a first relative movement, in particular rotation, relative to the second clamping element 24a. The stroke unit 26a has three first stroke elements 30a, 32a, 34a formed integrally with the first tightening element 22a. These three first stroke elements 30a, 32a, 34a are formed in a slope shape. Furthermore, the stroke unit 26a has three second stroke elements 36a, 38a, 40a. These three second stroke elements 36a, 38a, 40a are based on the first relative movement or rotation of the first clamping element 22a relative to the second clamping element 24a, and the first stroke element 30a. , 32a, 34a, the second relative movement or translation of the first clamping element 22a relative to the second clamping element 24a is generated by cooperation, ie, interaction. The second stroke elements 36a, 38a, 40a are also formed in a slope shape. Further, the second stroke elements 36a, 38a, 40a are formed integrally with the second tightening element 24a (see FIG. 5). The first stroke elements 30a, 32a, and 34a correspond to the second stroke elements 36a, 38a, and 40a, respectively. However, the first clamping element 22a is provided with more or less than three first stroke elements 30a, 32a, 34a, and the second clamping element 24a has three second strokes. It is also possible to provide elements 36a, 38a, 40a. The number of stroke elements 30a, 32a, 34a, 36a, 38a, and 40a that are advantageous for the first tightening element 22a and the second tightening element 24a is determined by a person skilled in the art upon request. . The first stroke elements 30a, 32a, 34a are evenly distributed along one 360 ° ring of the first clamping element 22a to accommodate the spindle 16a of the first clamping element 22a, respectively. It extends along an angle range of 30 ° to 60 ° with a central opening 94a provided in the center. The central opening 94a is formed as a fitting hole.

  The second stroke elements 36a, 38a, 40a are evenly distributed along one 360 ° ring of the second clamping element 24a to accommodate the spindle 16a of the second clamping element 24a, respectively. It extends along an angle range of 30 ° to 60 ° with a central opening 96a provided in the center (see FIG. 5). The second stroke elements 36a, 38a, 40a have a mathematically defined inclination in the direction of the first clamping element 22a starting from the inner surface 98a of the second clamping element 24a. In this case, the second stroke elements 36a, 38a, 40a have inclinations corresponding to the first stroke elements 30a, 32a, 34a. The inclinations of the first stroke elements 30a, 32a, 34a and the inclinations of the second stroke elements 36a, 38a, 40a are equal in magnitude, or the inclination of the thread 90a of the spindle 16a or the second tightening element. It is set larger than the inclination of the female thread 88a of 24a. During rotation of the first clamping element 22a relative to the second clamping element 24a based on the braking operation, the first stroke elements 30a, 32a, 34a slide on the second stroke elements 36a, 38a, 40a. To do. This generates an axial stroke of the first clamping element 22a relative to the second clamping element 24a along the axial direction 28a. This axial stroke maintains and / or increases the clamping force between the female thread 88a of the second clamping element 24a and the thread 90a of the spindle 16a, so that the clamping unit 12a from the spindle 16a. And / or dropping of the tool 14a can be prevented.

  The hand-held machine tool clamping device 10a has three contact elements 42a, 44a, and 46a. These abutment elements 42a, 44a, 46a have a first relative movement between the first clamping element 22a and the second clamping element 24a or a first relative to the second clamping element 24a. It is provided to limit the rotation of the tightening element 22a (see FIG. 5). The abutment elements 42a, 44a, 46a are arranged on the inner surface 98a of the second clamping element 24a facing the first clamping element 22a. The first tightening element 22a has three recesses 100a, 102a, and 104a (see FIG. 6). These recesses 100a, 102a, 104a are provided to accommodate the contact elements 42a, 44a, 46a. However, the second tightening element 24a is provided with more or less than three contact elements 42a, 44a, 46a, and the first tightening element 22a has three recesses 100a, 102a, 104a. Can be provided. It should be noted that those skilled in the art require how many abutment elements 42a, 44a, 46a are advantageous for the second clamping element 24a and how many recesses 100a, 102a, 104a are advantageous for the first clamping element 22a. It is decided according to.

  The three abutment elements 42a, 44a, 46a are evenly distributed along one 360 ° ring of the second clamping element 24a, spaced apart from each other and the second clamping element 24a is spaced from the three second stroke elements 36a, 38a, 40a. Further, the three contact elements 42a, 44a, 46a have an axially extending length extending along the axial direction 28a. This axially extending length is selected such that the three abutment elements 42a, 44a, 46a extend into the three recesses 100a, 102a, 104a of the first clamping element 22a. These three recesses 100a, 102a, 104a are evenly distributed in one 360 ° ring of the first clamping element 22a and extend along an angular range of 15 ° to 30 °, respectively. Are arranged at a distance from each other around a central opening 94a of the clamping element 22a and at a distance from the first stroke elements 30a, 32a, 34a.

  The abutment elements 42a, 44a, 46a rotate between the first clamping element 22a and the second clamping element 24a according to the dimensions of the recesses 100a, 102a, 104a and the dimensions of the abutment elements 42a, 44a, 46a. Is limited to the angular range defined by. Thereby, for example, the desired disengagement of the tightening unit 12a at the time of tool change becomes possible. When the tightening unit 12a is rotated in the clockwise direction or the rotation direction during the operation as viewed from the angle grinding machine 60a, the first tightening element 22a is relative to the second tightening element 24a. The contact elements 42a, 44a, 46a of the second tightening element 24a then contact the edge areas 106a, 108a, 110a of the recesses 100a, 102a, 104a of the first tightening element 22a. Touch. The first tightening element 22a is firmly connected to the second tightening element 24a by contact or contact of the contact elements 42a, 44a, 46a with the edge areas 106a, 108a, 110a of the recesses 100a, 102a, 104a. Yes.

  Furthermore, the hand-held machine tool clamping device 10a includes a number of lubricants for containing a lubricant for reducing friction during the first relative movement between the first clamping element 22a and the second clamping element 24a. A lubricant accommodating chamber 112a is provided. These lubricant accommodating chambers 112a are formed by a lubricant pocket 114a. These lubricant pockets 114a are equally spaced from each other along one circular ring centered on the opening 94a at the center of the first tightening element 22a (see FIG. 6). The lubricant pocket 114a is disposed on the surface 116a of the first tightening element 22a opposite to the contact surface 92a. Further, the slant-like first stroke elements 30a, 32a, 34a and the slant-like second stroke elements 36a, 38a, 40a are also provided with lubricant pockets (not shown). Slope-like first stroke elements 30a, 32a on the slope-like second stroke elements 36a, 38a, 40a during rotation of the first clamping element 22a relative to the second clamping element 24a, A low frictional resistance is achieved when sliding 34a.

  Furthermore, the second clamping element 24a has a bearing element 118a. The support element 118a is disposed in an annular recess 120a provided on the inner surface 98a of the second tightening element 24a. The bearing element 118a is formed as a sliding bearing. However, it is also possible for the bearing element 118a to be formed as a rolling bearing in an alternative form. Similarly, in the annular recess 120a, a plurality of lubricant pockets (not shown) for containing the lubricant are equally spaced from each other. Further, the bearing element 118a is made of an elastic material, for example, a spring elastic material, and is loaded in the annular recess 120a of the second tightening element 24a in a state where a preload is applied along the axial direction 28a. It is also possible to be housed in As a result, the surface pressure between the first stroke elements 30a, 32a, 34a and the second stroke elements 36a, 38a, 40a can be reduced, so that the first stroke elements 30a, 32a, 34a and the first stroke elements 30a, 32a, 34a Less friction between the two stroke elements 36a, 38a, 40a can be achieved. Furthermore, by forming the bearing element 118a from an elastic material, the first clamping element 22a and the second clamping element 24a are at least substantially unloaded, eg, after being removed from the spindle 16a. In the meantime, a return of the first clamping element 22a relative to the second clamping element 24a can be achieved.

  Further, the tightening unit 12a includes a first seal element 122a and a second seal element 124a. Both sealing elements 122a and 124a are provided to protect the tightening unit 12a from dust intrusion from the outside environment and to prevent lubricant from flowing out from the inside. The first seal element 122a is disposed in the first groove 126a of the second tightening element 24a, and the second seal element 124a is disposed in the second groove 128a of the second tightening element 24a. (See FIG. 5). The first groove 126a is disposed on the side surface 130a of the second clamping element 24a. The side surface 130a extends perpendicularly to the inner surface 98a of the second clamping element 24a and extends along the entire circumference of the second clamping element 24a extending in a plane parallel to the inner surface 98a. The second groove 128a is disposed on a surface 132a of the hollow cylinder 134a that faces the side surface 130a of the hollow cylinder 134a that surrounds the central opening 96a of the second clamping element 24a. The first seal element 122a is press-fitted in a state of being accurately fitted in the first groove 126a, and the second seal element 124a is press-fitted in a state of being accurately fitted in the second groove 128a. Has been.

  The first tightening element 22a similarly has a first groove 136a for accommodating the first sealing element 122a. The first groove 136a of the first tightening element 22a is disposed along the outer peripheral surface of the first tightening element 22a and extends along the entire outer peripheral surface. The outer peripheral surface of the first tightening element 22a extends at least in a plane extending substantially parallel to the contact surface 92a. The first groove 136a has an extending length along the axial direction 28a that is greater than the extending length of the first sealing element 122a along the axial direction 28a. This ensures a sealing function during the axial stroke of the first clamping element 22a relative to the second clamping element 24a.

  Furthermore, the first tightening element 22a has a second groove 138a for receiving the second sealing element 124a. The second groove 138a is disposed on the inner surface 140a of the central opening 94a of the first tightening element 22a and extends along the entire peripheral surface of the central opening 94a. The peripheral surface of the central opening 94a extends at least in a plane extending substantially parallel to the contact surface 92a of the first tightening element 22a. The second groove 138a has an extending length along the axial direction 28a that is greater than the extending length of the second sealing element 124a along the axial direction 28a. This also ensures a sealing function during the axial stroke of the first sealing element 122a relative to the second clamping element 24a. The first tightening element 22a and the second tightening element 24a are coupled to each other by the first seal element 122a and the second seal element 124a, and are fixed in position in the axial direction.

  7 to 10 show two alternative embodiments. Almost unchanged components, features and functions are basically labeled with the same reference numerals. In order to distinguish the embodiments, letters a to c are added to the reference numerals of the embodiments. The following description is mainly limited to the difference from the first embodiment shown in FIGS. Constituent components, features and functions are described in the description of the first embodiment shown in FIGS.

  FIG. 7 shows a perspective detail view of an alternative hand-held machine tool clamping device 10b according to the present invention in an open state including a similar cross section along line VV in FIG. . This hand-held machine tool fastening device 10b has a fastening unit 12b. The tightening unit 12b is provided for tightening the tool 14b to the spindle 16b. The tightening unit 12b includes a first tightening element 22b and a second tightening element 24b that can move relative to the first tightening element 22b. Furthermore, the hand-held machine tool clamping device 10b has a dropout prevention unit 18b for avoiding the dropout of the clamping unit 12b and / or the tool 14b from the spindle 16b. The dropout prevention unit 18b has a motion change unit 20b formed as a stroke unit 26b. The motion changing unit 20b is provided for converting the first relative motion between the first tightening element 22b and the second tightening element 24b into the second relative motion during the braking operation.

  The stroke unit 26b includes three first stroke elements 30b, 32b, and 34b disposed on the surface 116b of the first tightening element 22b opposite to the contact surface 92b. Further, the stroke unit 26b has three second stroke elements 36b, 38b, 40b formed integrally with the second tightening element 24b. These second stroke elements 36b, 38b, 40b are formed in a slope shape. The first stroke elements 30b, 32b, 34b are formed as rolling elements 142b, 144b, 146b. These rolling elements 142b, 144b, 146b are disposed in recesses 148b, 150b, 152b provided on the surface 116b of the first tightening element 22b on the side opposite to the contact surface 92b. These recesses 148b, 150b, and 152b are evenly distributed along one circular ring, and are disposed on the first tightening element 22b at a distance from each other. The rolling elements 142b, 144b, 146b of the first tightening element 22b correspond to the inclined second stroke elements 36b, 38b, 40b of the second tightening element 24b. However, in an alternative form, the first stroke elements 30b, 32b, 34b are integrally formed on the first clamping element 22b in a slanted manner, and the second stroke elements 36b, 38b, 40b are rolled. It is also possible to be formed as a moving body and to be arranged in a recess provided in the second clamping element 24b. When the first tightening element 22b rotates relative to the second tightening element 24b based on the braking operation, the rolling elements 142b, 144b, 146b move along the inclined second stroke elements 36b, 38b, 40b. Rolling, thus generating an axial stroke along the axial direction 28b of the first clamping element 22b relative to the second clamping element 24b.

  FIG. 8 shows another alternative hand-held machine tool clamping device 10c. This hand-held machine tool fastening device 10c has a fastening unit 12c. The tightening unit 12c is provided for tightening the tool 14c to the spindle 16c in the axial direction 28c. In order to avoid dropping of the tightening unit 12c and / or the tool 14c from the spindle 16c during the braking operation, the hand-held machine tool tightening device 10c has a drop-off preventing unit 18c. The dropout prevention unit 18c has a motion change unit 20c. This movement changing unit 20c is provided for converting the first relative movement between the first clamping element 22c and the second clamping element 24c of the clamping unit 12c into a second relative movement during braking operation. ing. The motion change unit 20c is formed as a stroke unit 26c. The stroke unit 26c is provided for generating relative movement of the first clamping element 22c relative to the second clamping element 24c at least along the axial direction 28c during braking operation. The stroke unit 26c is formed as a cam transmission 154c. The cam transmission 154c has two stroke elements 30c and 32c formed as control notches 48c and 50c. One of the two control elements 52c and 54c of the cam transmission 154c is engaged in both the stroke elements 30c and 32c. However, it is also possible for the cam transmission 154c to have a different number of control elements 52c, 54c and control notches 48c, 50c that would be advantageous to those skilled in the art. A person skilled in the art will provide an appropriate number of control elements 52c, 54c and control notches 48c, 50c depending on the mode of use.

  The control elements 52c and 54c are movably disposed in the control notches 48c and 50c. Further, the control elements 52c and 54c are formed in a pin shape. The control elements 52c and 54c are fixed to the two recesses 158c and 160c of the second tightening element 24c by press fitting, respectively. However, the control elements 52c, 54c are fixed in position on the spindle 16c by other forms of coupling that may be advantageous to those skilled in the art, for example, frictional connection or force transmission and / or material connection. It is also possible. The recesses 158c and 160c are arranged on the diametrically opposite sides of the surface 162c of the second tightening element 24c extending along the circumferential direction 58c. Accordingly, the recesses 158c and 160c are evenly distributed along the circumferential direction 58c and arranged in the second tightening element 24c. The control notches 48c and 50c of the cam transmission 154c are arranged in the first tightening element 22c. The control cutouts 48c and 50c have a length extending over an angular range of about 20 ° along the circumferential direction 58c on the surface 156c of the first clamping element 22c extending along the circumferential direction 58c. Further, the control notches 48c and 50c have a mathematically defined inclination in the axial direction 28c when viewed along the circumferential direction 58c. The control elements 52c and 54c extend into the control cutouts 48c and 50c starting from the second tightening element 24c.

  The control elements 52c, 54c cooperate with the control notches 48c, 50c so that the first clamping element 22c and the second clamping element 24c of the clamping unit 12c during the braking operation of the angle grinding machine 60c. Is provided to convert the relative motion of the second to the second relative motion. The first clamping element 22c is based on a rotational movement relative to the second clamping element 24c and the spindle 16c, and relative to the second clamping element 24c, along the rotation axis 86c of the spindle 16c. It is translated in the direction of the tool 14c. Translational movement of the first clamping element 22c along the section x is limited by the dimensions of the control notches 48c, 50c.

  During the working operation of the angle grinding machine 60c, the control elements 52c and 54c are arranged in the tool-side range 164c of the control notches 48c and 50c, respectively. In this case, the first clamping element 22c and the second clamping element 24c are in contact with the surface 166c of the tool 14c, which is directed to the clamping unit 12c. However, during work operation, the second clamping element 24c is spaced from the surface 166c of the tool 14c facing the clamping unit 12c, and only the first clamping element 22c is present. It is also possible to contact the surface 166c of the tool 14c, which is directed to the clamping unit 12c. The abutment surface 92c of the tool 14c that contacts the surface 166c of the tool 14c that faces the clamping unit 12c is provided with an adhesive coating layer having a high coefficient of friction. The surface 166c of the tool 14c facing the clamping unit 12c is also provided with an adhesion coating layer. As a result, it is possible to guarantee the transmission of the rotational force at the time of detachment and / or during braking operation.

  During the braking operation, the rotation between the first tightening element 22c and the second tightening element 24c is generated from the torque difference between the tool 14c and the tightening unit 12c. The tool 14c rotates the first clamping element 22c together by friction formed between the tool 14c and the contact surface 92c of the first clamping element 22c. Due to the engagement of the control elements 52c, 54c into the control notches 48c, 50c and the inclination of the control notches 48c, 50c, the first tightening element 22c is relative to the second tightening element 24c. Based on the rotation, it is translated along the axial direction 28c. At that time, the first tightening element 22c applies force to the tool 14c along the axial direction 28c. Accordingly, the tool 14c is pressed toward the spindle 16c along the axial direction 28c, whereby the clamping force continues to be maintained at the thread 90c of the spindle 16c and the female thread 88c of the second clamping element 24c, and / Or increased. As a result, it is possible to prevent the tool 14c from being loosened during the braking operation, and thus the tool 14c and / or the fastening unit 12c from falling off.

  Due to the torque difference between the tool 14c and the tightening unit 12c during the braking operation, the control elements 52c and 54c are controlled based on the first relative movement between the first tightening element 22c and the second tightening element 24c. Inside the notches 48c and 50c, the control notches 48c and 50c are moved in the direction of the range 168c on the tightening element side. This clamping element side area 168c of the control cutouts 48c, 50c is arranged on the side of the control cutouts 48c, 50c closer to the second fastening element 24c, respectively. In this case, the second clamping element 24c is separated from the surface 166c of the tool 14c directed to the clamping unit 12c. When the control elements 52c and 54c come into contact with the machine-side range 168c of the control notches 48c and 50c, the first tightening element 22c has advanced in the section x along the axial direction 86c. Similarly, the control elements 52c and 54c have moved in the section x along the axial direction 86c with respect to the tool-side range 164c of the control notches 48c and 50c. Accordingly, the translational movement of the first clamping element 22c is limited by the distance between the tool-side range 164c and the clamping element-side range 168c along the inclination of the control notches 48c and 50c (see FIG. 10).

  In order to ensure torque transmission and / or force transmission between the first tightening element 22c and the tool 14c during braking operation, the cam transmission 154c has two spring elements 56c. Both spring elements 56c are provided to preload the first clamping element 22c relative to the control elements 52c, 54c (FIG. 10 shows only one spring element). The spring element 56c is formed as a tension spring 172c. However, it is also possible for the spring element 56c to be formed in another form that would be advantageous to those skilled in the art, such as an elastomer element or the like. The tension spring 172c is located in one of the control cutouts 48c and 50c, along the circumferential direction 58c, and within the range 168c on the tightening element side of the control cutouts 48c and 50c and within each control cutout 48c and 50c. It arrange | positions between the engaged control elements 52c and 54c. Accordingly, the tension spring 172c applies a spring force along the circumferential direction 58c to the first clamping element 22c. A preload is applied to the first tightening element 22c in the direction of the second tightening element 24c based on the spring force of the tension spring 172c. Accordingly, the tightening unit 12c is returned to the basic position in a substantially unloaded state, thereby reliably performing relative movement between the first tightening element 22c and the second tightening element 24c during the braking operation. be able to.

  Furthermore, the first clamping element 22c has a lubricant containing element (not shown) on a surface 170c directed to the second clamping element 24c. This lubricant containing element is provided to allow relative movement between the first tightening element 22c and the second tightening element 24c with less friction. It is also possible for the lubricant containing element to be arranged on the second clamping element 24c or on both the first transmission element 22c and the second clamping element 24c.

  The hand-held machine tool clamping device 10c has two contact elements 42c and 44c. Both abutment elements 42c, 44c are either a first relative movement between the first clamping element 22c and the second clamping element 24c or a first clamping element 22c relative to the second clamping element 24c. It is provided to limit the rotation. The abutment elements 42c and 44c are arranged to reach the end positions when the first clamping element 22c is rotated relative to the ends of the control cutouts 48c and 50c, that is, relative to the second clamping element 24c. The control elements 52c and 54c are formed by end portions that come into contact.

10a, 10b, 10c Handheld machine tool clamping device 12a, 12b, 12c Tightening unit 14a, 14b, 14c Tool 16a, 16b, 16c Spindle 18a, 18b, 18c Fall-off prevention unit 20a, 20b, 20c Motion change unit 22a, 22b, 22c first clamping element 24a, 24b, 24c second clamping element 26a, 26b, 26c stroke unit 28a, 28b, 28c axial direction 30a, 32a, 34a, 30b, 32b, 34b, 30c, 32c first stroke element 36a, 38a, 40a, 36b, 38b, 40b Second stroke element 42a, 44a, 46a, 42c, 44c Abutment element 48c, 50c Control notch 52c, 54c Control element 56c Spring element 58 , 58c Circumferential direction 60a, 60c Angle grinding machine 62a Hand-held machine tool 64a Protective hood unit 66a Hand-held machine tool housing 68a Main hand grip 70a Opposite to the tool 72a Main extension direction 74a Motor housing 76a Transmission housing 78a Auxiliary hand Grip 80a Mounting flange 82a Flattened portion 84a Two-sided cut portion 86a, 86c Rotating axis 88a, 88c Female thread 90a, 90c Screw thread 92a, 92b, 92c Abutting surface 94a Opening 96a Opening 98a Inner surface 100a, 102a, 104a Concave 106a, 108a, 110a Edge range 112a Lubricant storage chamber 114a Lubricant pocket 116a, 116b Surface opposite to the contact surface 118a Bearing element 120a Recessed portion 122a First Seal element 124a Second seal element 126a First groove 128a Second groove 130a Side surface 132a Side surface 134a Hollow cylindrical body 136a First groove 138a Second groove 140a Inner surface 142b, 144b, 146b Rolling element 148b, 150b, 152b Recessed portion 154c Cam transmission device 156c Surface extending along the circumferential direction 158c, 160c Recessed portion 162c Surface extending along the circumferential direction 164c Range on the tool side 166c Surface facing the tightening unit 168c Range on the tightening element side 170c Surface directed to the second clamping element 172c Tension spring 174a Surface opposite to the contact surface 176a Rotational force transmission hole 178a Rotational force transmission hole x section

Claims (11)

A hand-held machine tool clamping device comprising at least one clamping unit (12a; 12b; 12c) provided for clamping the tool (14a; 14b; 14c) to the spindle (16a; 16b; 16c) The clamping unit (12a; 12b; 12c) is provided for clamping the tool (14a; 14b; 14c) axially to the spindle (16a; 16b; 16c) against the mounting flange (80a; 80c). And at least one drop-off prevention unit (18a; 18b) for avoiding dropping of the clamping unit (12a; 12b; 12c) and / or the tool (14a; 14b; 14c) from the spindle (16a; 16b; 16c). ; 18c) is provided, said disengagement prevention unit (18a; 18b; 18 c) at least partly a first relative movement between at least two clamping elements (22a, 24a; 22b, 24b; 22c, 24c) of the clamping unit (12a; 12b; 12c) during braking operation. Having at least one motion change unit (20a; 20b; 20c) provided for conversion into two relative motions , the first clamping element (22a; 22b; 24c) being circumferential (58a; 58b; 58c) and a hand-held machine tool clamping device supported on the second clamping element (24a; 24b; 22c) movably along the axial direction (28a; 28b; 28c) At least one relative movement between the two clamping elements (22a, 24a; 22b, 24b; 22c, 24c) At least one abutment element is provided for limiting to (42a, 44a, 46a; 42c , 44c) , characterized in that it has a hand-held machine tool clamping device.   A motion change unit (20a; 20b; 20c) is adapted to axially move (28a; 28b; 28c) relative movement of at least one of the two clamping elements (22a, 24a; 22b, 24b; 22c, 24c) during the braking operation. 2. Hand-held machine tool clamping device according to claim 1, wherein the device is formed as a stroke unit (26 a; 26 b; 26 c) provided for generation along the line.   The stroke unit (26a; 26b; 26c) has at least one stroke element (30a, 32a, 30b) formed at least partially integral with one of the two clamping elements (22a, 24a; 22b, 24b; 22c, 24c). 34a, 36a, 38a, 40a; 30b, 32b, 34b; 30c, 32c).   The hand-held machine tool clamping device according to claim 3, wherein the stroke units (30a, 32a, 34a, 36a, 38a, 40a; 30b, 32b, 34b; 30c, 32c) are formed in a slope shape. The stroke unit (26c) is formed as a cam transmission (154c), and the cam transmission (154c) is at least one stroke element (30c, 32c) formed as a control notch (48c, 50c). the has at least one control element (52c, 54c) of about the row element (30c, 32c) cam gear in (154c) is at least partially engaged, claims 1 to 4 The hand-held machine tool clamping device according to any one of the above. The hand-held machine tool clamping device according to claim 5 , wherein the control element (52c, 54c) is formed in a pin shape. The hand-held machine tool clamping device according to claim 5 , wherein the control notch (48c, 50c) is arranged in one clamping element (22c) of the clamping unit (12c). At least one spring element provided with a cam transmission (154c) for preloading said one clamping element (22c) of the clamping unit (12c) relative to the control element (52c, 54c) The hand-held machine tool clamping device according to claim 7 , comprising (56c). The control notch (48c, 50c) has an extension length along an angular range smaller than 40 ° on the surface (156c) extending along the circumferential direction (58c) of the one clamping element (22c). The hand-held machine tool clamping device according to claim 7 . A hand-held machine tool, wherein the hand-held machine tool fastening device according to any one of claims 1 to 9 is provided. The hand-held machine tool according to claim 10 , wherein the hand-held machine tool is an angle grinding machine.

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