Hand-held power tool with a switching unit
10478961 ยท 2019-11-19
Assignee
Inventors
- Daniel Barth (Leinfelden-Echterdingen, DE)
- Cornelius Boeck (Kirchheim, DE)
- Sinisa Andrasic (Schoenaich, DE)
Cpc classification
H01H3/20
ELECTRICITY
H01H9/06
ELECTRICITY
B25F5/02
PERFORMING OPERATIONS; TRANSPORTING
H01H3/14
ELECTRICITY
B24B23/02
PERFORMING OPERATIONS; TRANSPORTING
International classification
B24B23/02
PERFORMING OPERATIONS; TRANSPORTING
H01H3/20
ELECTRICITY
Abstract
A hand-held power tool, in particular an angle-grinding machine, includes a housing, a switching unit, a motor, and at least one first pivot unit and one second pivot unit. The switching unit includes a ratchet element arranged on the housing. The first and second pivot units are configured to mount the ratchet element on the housing so as to be movable. Each of the first and the second pivot units includes at least one housing-side bearing unit and one ratchet-side bearing unit. The hand-held power tool further includes a coupling unit configured to couple the first pivot unit with the one second pivot unit.
Claims
1. A hand-held power tool, comprising: a housing; a switching unit including a ratchet element arranged on the housing; a motor; at least one first pivot unit and one second pivot unit, the first and second pivot units configured to mount the ratchet element on the housing of the hand-held power tool so as to be movable; and a coupling unit configured to couple the first pivot unit with the second pivot unit, wherein each of the first and the second pivot units includes at least one housing-side bearing unit and one ratchet-side bearing unit.
2. The hand-held power tool according to claim 1, wherein: each of the first and the second pivot units includes a first arm configured to connect the housing-side bearing unit to the ratchet-side bearing unit, and the first arm of the first pivot unit and the first arm of the second pivot unit are configured such that first arm of the first pivot unit is always moved parallel to the first arm of the second pivot unit.
3. The hand-held power tool according to claim 1, wherein: each of the first and the second pivot units includes one second arm configured to connect the housing-side bearing unit to a further bearing unit, and the further bearing unit is configured to mount the coupling unit on the first and the second pivot units.
4. The hand-held power tool according to claim 1, wherein: an axial extent of the coupling unit corresponds to a distance between the housing-side bearing unit of the first pivot unit and the housing-side bearing unit of the second pivot unit.
5. The hand-held power tool according to claim 1, wherein: the coupling unit is one of: a rod element, a plastics material part, and a sheet metal bending part.
6. The hand-held power tool according to claim 1, wherein: the first and the second pivot units are rotatably mounted such that rotational movement of the first pivot unit follows rotational movement of the second pivot unit.
7. The hand-held power tool according to claim 1, wherein: at least one of the housing-side bearing units and/or at least one of the ratchet-side bearing unit of the first pivot unit and/or the second pivot unit includes a linear guide.
8. The hand-held power tool according to claim 1, wherein: the first pivot unit is spaced from the second pivot unit by at least a length of 25% of an axial extent of the ratchet element.
9. The hand-held power tool according to claim 1, wherein: in at least one state of the hand-held power tool, a switching element of the switching unit is actuated in a translatory manner by the ratchet element.
10. The hand-held power tool according to claim 1, wherein: the coupling unit includes a toothed wheel element.
11. The hand-held power tool according to claim 10, wherein: an angle between the first arm of the first pivot unit and a radial axis of the hand-held power tool is configured to be set to a value of between 60 and 120.
12. The hand-held power tool according to claim 11, wherein: the value is between 70 and 110.
13. The hand-held power tool according to claim 1, wherein: the coupling unit is a scissors lifting unit.
14. The hand-held power tool according to claim 13, wherein: an angle between the first arm of the first pivot unit and an axial axis of the hand-held power tool is configured to be set to a value of between 0 and 30.
15. The hand-held power tool according to claim 14, wherein: the value is between 0 and 20.
16. The hand-held power tool according to claim 1, further comprising: a resetting element configured to provide a resetting force in opposition to an actuating direction of the ratchet element, wherein the resetting element is arranged on at least one of the first pivot unit and the second pivot unit.
17. The hand-held power tool according to claim 16, wherein: the first and the second pivot units form one structural unit with the coupling unit and with the resetting element.
18. The hand-held power tool according to claim 16, wherein: the resetting element is a leg spring.
19. The hand-held power tool according to claim 1, wherein: the first and the second pivot units are rotatably mounted such that rotational movement of the first pivot is effected in an opposite direction as rotational movement of the second pivot unit.
20. The hand-held power tool according to claim 1, wherein: in at least one state of the hand-held power tool, a switching element of the switching unit is actuated in a rotational manner by at least one of the first pivot unit and the second pivot unit.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Further advantages are produced from the following description of the drawings. Exemplary embodiments of the disclosure are shown in the drawings. The drawing, and the description include numerous features in combination. The person skilled in the art will also look expediently at the features individually and form them into sensible further combinations.
(2) The drawings are as follows:
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DETAILED DESCRIPTION
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(20) The motor housing 30 includes, as an example, two portions. The first portion of the motor housing 30 is realized in the manner of a hollow cylinder. In particular, an electric motor 32 is arranged in the first portion of the motor housing 30. The first portion of the motor housing 30 is loosely connected to the gear head 20 on a first connecting region 31. A fan 34, which is realized for the purpose of generating a cooling air flow for cooling the electric motor 32, is arranged on the motor-housing-side in the first connecting region 31 of the motor housing 30. The electric motor 32 includes a drive shaft 38 which is coupled with the output spindle 26 by means of a crown wheel 28. The drive shaft 38 extends along the axial axis 1 of the hand-held power tool 10. In particular, the rotational axis of the drive shaft 38 corresponds to the axial axis 1 of the hand-held power tool 10. In the second connecting region 39 of the motor housing 30, the outside contour of the motor housing 30 merges into the outside contour of the handle housing 40. The handle housing 40 is realized as a housing cover or rather in a pot-shaped manner The handle housing 40 comprises lateral air inlet openings 45, through which the cooling air is able to enter into the housing 12 of the hand-held power tool 10. As an example, the handle housing 40 includes two housing half-shells which can be fastened together and to the motor housing by means of a fastening element, as an example screws. The second portion of the motor housing 30 is realized as a continuation which is encased by the handle housing 40. The second portion of the motor housing 30 is provided for the bearing arrangement or receiving of hand-held power tool components, in particular, the electronics 46, the switching unit 100 and the power supply unit 42. The hand-held power tool 10 is shown in the form of a mains-operated hand-held power tool which comprises a mains cable 44 for the power supply on the rear end 41 of the hand-held power tool 10. However, it is also conceivable for the power supply unit 42 to comprise a rechargeable battery pack interface which is connectable mechanically and electrically to a rechargeable battery pack interface of a rechargeable battery pack. A rechargeable battery pack is to be understood, in this case, as one or several battery cells which are connected together and are arranged in a housing. The housing of the rechargeable battery pack, in this case, comprises a rechargeable battery pack interface on its outside surface.
(21) The switching unit 100 of the hand-held power tool 10 includes a ratchet element 102 and a switching element 104. The ratchet element 102 is arranged at least in part in a recess of the motor housing 30 and of the handle housing 40. The ratchet element 102 forms at least in part the outside contour 13 of the housing 12 of the hand-held power tool 10. The ratchet element 102 comprises a control surface 103, which is actuated by a user, in particular, by the fingertips of a hand of the user, for actuating the ratchet element 102. The transition from the outside contour 13 of the motor housing 30 to the outside contour 103 of the ratchet element 102, in particular of the control surface 103 of the ratchet element 102, is realized as a step. In an advantageous manner, the control surface 103 of the ratchet element 103 is realized so as to be identifiable by the hand of a user when it touches the step.
(22) The ratchet element 102 is connected by means of a first pivot unit 110 and a second pivot unit 130 to the housing 12, in particular to the motor housing 30, of the hand-held power tool 10 so as to be movable.
(23) The first and the second pivot units 110, 130 are connected to the housing 12, in particular to the motor housing 30, of the hand-held power tool in each case by means of a housing-side bearing unit 112, 113. The housing-side bearing unit 112, 132 comprises, as an example, a receiving bore 113, 133 which is provided for receiving a bolt or a pin 111, 131. The pin 111, 131 forms a housing-side rotational axis 114, 134 about which the first and the second pivot units 110, 130 are mounted in each case so as to be rotatable relative to the housing 12 of the hand-held power tool 10.
(24) The first and the second pivot units 110, 130 are connected to the ratchet element 102 in each case by means of a ratchet-side bearing unit 118, 138. The ratchet-side bearing unit 118, 138 comprises, as an example, a receiving bore 119, 139 which is provided for receiving a bolt or a pin 117, 137. The pin 117, 137 forms a ratchet-side rotational axis 115, 135 about which the first and the second pivot units 110, 130 are mounted in each case so as to be rotatable relative to the ratchet element 102.
(25) The housing-side rotational axis 114 of the first pivot unit 110 extends parallel to the housing-side rotational axis 134 of the second pivot unit 130. The ratchet-side rotational axis 115 of the first pivot unit 110 extends parallel to the ratchet-side rotational axis 135 of the second pivot unit 130. In particular, the housing-side rotational axes 114, 134 of the first and of the second pivot units 110, 130 extend parallel to the ratchet-side rotational axes 115, 135 of the first and of the second pivot units 110, 130.
(26) The first and the second pivot units 110, 130 comprise in each case another further bearing unit 120, 140 which is realized for the purpose of mounting a coupling unit 150 at least in part. The coupling unit 150 is realized, as an example, as a rod element 152. As shown in
(27) The housing-side bearing units 112, 132 of the first and of the second pivot units 110, 130 are connected in each case to the ratchet-side bearing units 118, 138 of the first and of the second pivot units 110, 130 by means of a first arm 122, 142. The pivot units 110, 130 are formed, as an example, from a hard elastic plastics material. A second arm 124, 144 connects the housing-side bearing units 112, 132 of the first and of the second pivot units 110, 130 in each case to the further bearing units 120, 140 of the first and of the second pivot units 110, 130. The first 122, 142 arm is connected, as an example, to the second arm 124, 144, in particular is realized integrally or rather as one component.
(28) The first arm 122, 142 and the second arm 124, 144 are arranged advantageously within an angular range of between 65 and 115 with respect to one another, as an example at an angle of substantially 90. To calculate the angle, in this case, a straight line is produced through the first arm 122, 142, which line extends perpendicular from the housing-side rotational axis 114, 134 to the ratchet-side rotational axis 115, 135, and a straight line is produced through the second arm, which line extends perpendicular from the housing-side rotational axis 114, 134 to the rotational axis of the further bearing unit 120, 140.
(29) The first arm 122 of the first pivot unit 110 is realized advantageously parallel to the first arm 142 of the second pivot unit 130. In addition, the distance between the housing-side bearing unit 112 of the first pivot unit 110 and the ratchet-side bearing unit 118 of the first pivot unit is realized so as to be substantially identical to the distance between the housing-side bearing unit 132 of the second pivot unit 130 and the ratchet-side bearing unit 138 of the second pivot unit 130, as a result of which a parallelogram arrangement is realized.
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(31) The force to be expended to actuate the switching unit 100 is able to be advantageously reduced as a result of lever transmission. The force to be expended is produced from the ratio between the distance between the housing-side rotational axis 134 of the second pivot unit 130 and the ratchet-side rotational axis 135 of the second pivot unit 130, on the one side, and the distance between the housing-side rotational axis 134 of the second pivot unit 130 and the contact surface of the further arm 146 of the second pivot unit 130 on the push button 106 of the switching element 104, on the other side. A smaller engagement force is possible as a result of said transmission ratio. The two arms 142, 146 comprise, in particular, a length ratio of 12.7 mm to 16.5 mm with respect to one another. The stroke of the push button 106 of the switching element 104 is, as an example, 5 mm. Consequently, a stroke of 6.6 mm is produced, as an example, on the ratchet 102.
(32) The first pivot unit 110 is spaced, in particular, in an axial manner, from the second pivot unit 130 by at least 35% of the axial extent of the ratchet element 102. In an advantageous manner, a substantially constant movement of the ratchet element 102 can be realized as a result of the mounting of the ratchet element 102 on the first and the second pivot units 110, 130. In particular, during actuation, the control surface 103 of the ratchet element 102 is moved toward the axial axis 1 in a manner substantially parallel to the axial axis 1 of the hand-held power tool 10. The axial axis 1 of the hand-held power tool extends through the drive shaft 38 of the motor 32.
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(37) The coupling unit 350 comprises a coupling element 352 in the form of a toothed wheel which is arranged along the axial axis 1 of the hand-held power tool 10 between the first and the second pivot units 310, 330. In addition, the coupling unit 350 includes the toothed wheel elements 351, 353 of the first and of the second pivot units 310, 330. The coupling element 352 is rotatably connected, as an example, to the housing 12 of the hand-held power tool 10. The coupling element 352 is rotatably mounted, as an example, by means of a bolt 355 of the housing 12 of the hand-held power tool 10. The coupling element 352 is arranged in such a manner that the teeth of the coupling element 352 engage between the teeth of the toothed wheel elements 351, 353 of the first and second pivot units 310, 330. As an alternative to this, it is also conceivable for the coupling element 352 to be rotatably connected to the ratchet 102.
(38) As an alternative to this, it is also conceivable for the coupling element 352 to be realized in the form of a toothed wheel which is formed in a flattened manner and comprises a toothing only in part along the circumference. This results in an advantageous manner in installation space being able to be saved.
(39) As a result of actuating the ratchet element 102 of the switching unit 100, in a manner analogous to the embodiment according to
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(43) When the ratchet element 102 is actuated, a rotational movement of the first and of the second pivot units 510, 530 is effected about the coupling element 552. In this case, the distance, in particular the distance along a parallel line to the radial axis 2 of the hand-held power tool, between the housing-side bearing unit 532 of the second pivot unit 530 and the ratchet-side bearing unit 518 of the first pivot unit 510 is continuously reduced. In the actuated state, the two bearing units can overlap in a radial manner.
(44) When the ratchet element 102 is actuated, the angle c between the first arm of the first pivot unit 510 and the first arm of the second pivot unit 530 decreases, as an example, from a value of 50 in the non-actuated state (see
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