Multi-functional hand-held power tool
By introducing a settable clutch and settable collar design into a multi-functional handheld power tool, the problem of complex mode selection in the prior art is solved, enabling quick and easy switching of operating modes and single mode selection, thus improving the user experience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TECHTRONIC CORDLESS GP
- Filing Date
- 2020-09-24
- Publication Date
- 2026-07-31
AI Technical Summary
Existing multi-functional handheld power tools require manual selection of operating modes, and the mode selection device is complex, making it difficult to switch operating modes quickly and accurately.
It adopts a settable clutch and settable collar design, which enables quick switching of operating modes through a single mode selector, and combined with a locking mechanism to ensure single mode selection, simplifying operation.
It enables quick and easy switching between multiple operating modes, ensuring that only one operating mode can be selected at any time, thus improving ease of use and security.
Smart Images
Figure CN116171209B_ABST
Abstract
Description
Background Technology
[0001] This invention relates to multi-functional handheld power tools, and more particularly to multi-functional handheld power tools having two or more, preferably three, operating modes.
[0002] In multi-function handheld power tools with two or more operating modes, the user must manually select the appropriate operating mode and the corresponding cutting head for the task at hand. Some tools have two separate mode selection devices, where one mode selector (e.g., a linear switch) changes the tool between hammer and non-hammer functions, while a second mode selector (e.g., a rotary collar) selects between limited and unlimited torque output. Preferably, multi-function handheld tools have a single mode selector switch, which not only facilitates quick and easy selection between two or more operating modes but also allows for the selection of only one operating mode at any given time. Summary of the Invention
[0003] According to one aspect of the present invention, a multi-functional handheld power tool is provided, the multi-functional handheld power tool comprising:
[0004] A motor housing and a motor located inside the housing, the motor having a motor output section, and a reduction gear installed to the motor output section so as to rotate together with the motor output section;
[0005] A configurable clutch is connected to the reduction gear to transmit torque from the reduction gear to the output spindle connected to the chuck;
[0006] A transmission housing connected to a motor housing, having a first housing portion connected to the motor housing and a second housing portion extending from the first portion toward the chuck, wherein at least a portion of the reduction gear and the clutch are located within the first portion of the transmission housing;
[0007] A setting collar is rotatably mounted on the second housing portion of the transmission housing and is rotatable between a plurality of predetermined angular positions, at least one of which corresponds to the tool’s unrestricted torque first operating mode and the remaining positions correspond to different torque output levels of the tool’s restricted torque second operating mode.
[0008] The configurable clutch includes: a clutch face having a plurality of clutch ramps extending a fixed axial distance from a linear portion of the clutch face; a clutch washer; and a clutch sleeve rotatably positioned axially about a second portion of the transmission housing and positioned between the set collar and the second portion of the transmission housing at a variable axial distance from the clutch washer; a clutch spring biased between the clutch sleeve and the clutch washer; and a follower positioned between the clutch face and the clutch washer, wherein...
[0009] The clutch sleeve is rotatably fixed to and rotatable with the setting ring to move axially on the second part of the transmission housing, such that the variable axial distance depends on a corresponding predetermined angular position among the predetermined angular positions of the plurality of setting rings, wherein the fixed axial distance is greater than the variable axial distance in at least one angular position of the setting ring corresponding to the first unrestricted torque operating mode of the tool, and the variable axial distance is greater than the fixed axial distance in the remaining predetermined angular positions of the setting ring.
[0010] Preferably, at least a second predetermined angular position of the predetermined angular position of the setting collar corresponds to the third unrestricted torque operating mode of the tool, wherein, in the second predetermined angular position of the predetermined angular position, the fixed axial distance is greater than the variable axial distance.
[0011] Preferably, in at least one of the first and second predetermined angular positions of the predetermined angular position of the set collar, corresponding to the first or third unrestricted torque operating mode of the tool, a portion of the clutch sleeve engages with a portion of the clutch washer.
[0012] Preferably, the clutch sleeve and the clutch washer are positioned outside the transmission housing, and the clutch sleeve is threadedly engaged with a second portion of the transmission housing to convert rotational movement of the clutch sleeve into axial movement along the second portion of the transmission housing.
[0013] Preferably, the clutch washer is positioned adjacent to the transition between the first and second portions of the transmission housing, and wherein the driven member includes a pin extending through a hole in the transmission housing.
[0014] Preferably, the multi-functional handheld power tool further includes a pair of opposing ratchet discs positioned within a second portion of the transmission housing and arranged to selectively apply axial vibration or impact to the output spindle; a locking mechanism, a portion of which is rotatable with the setting collar, having engaged positions corresponding to certain angular positions of the setting collar, these angular positions corresponding to different torque output levels of the tool's restricted torque second operating mode; and disengaged positions corresponding to either a first or second angular position of the setting collar, one of which corresponds to the tool's unrestricted torque first or third operating mode, wherein, in the engaged position, axial vibration or impact to the output spindle is suppressed, and in the disengaged position, axial vibration or impact to the output spindle can be achieved.
[0015] Preferably, the locking mechanism includes a ring and an axial arm. The ring is coupled to rotate with the set collar and has a radially outwardly extending recess. The axial arm is coupled to move axially but not rotatably with the output spindle and has a radially outwardly extending tab. In the disengaged position, the radially outwardly extending recess and the radially outwardly extending tab are rotatably aligned, allowing the tab to pass through the recess to allow axial movement of the arm and the output spindle.
[0016] Further aspects of the invention will become apparent from the following description and accompanying drawings, which are illustrated by way of example only. Attached Figure Description
[0017] Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:
[0018] Figure 1 This is a perspective view showing a multi-functional handheld power tool constructed according to the present invention.
[0019] Figure 2 This is a cross-sectional view showing certain features of the gear transmission, clutch mechanism, and hammer mechanism of a multi-functional handheld power tool.
[0020] Figure 3 This is a partially exploded perspective view of the transmission housing, showing some components of the clutch mechanism and the hammer locking mechanism.
[0021] Figure 4 This is a partial view of the gear transmission and clutch mechanism in the tool's first "screwdriver mode".
[0022] Figure 5 This is a partial view of the gear transmission and clutch mechanism in the tool's second "drill-only mode".
[0023] Figure 6 This is a partial view of the gear transmission and clutch mechanism in the tool's third "hammer drill mode".
[0024] Figure 7 This is a partial view of the hammer locking mechanism in the enabled position during the tool's first and second operating modes.
[0025] Figure 8 This is a partial view of the hammer locking mechanism in the deactivated position during the tool's third operating mode, and...
[0026] Figure 9 This is a diagram of the components of a hammer mechanism, including a hammer locking mechanism. Detailed Implementation
[0027] The following description of the invention is intended to be illustrative using language that is more or less specific to the structural or methodological features of handheld power tools. It should be understood that the invention is not limited to the specific features shown or described, as the apparatus described herein includes preferred forms for carrying out the invention. Variations and modifications to the forms disclosed herein may be made based on the description without departing from the scope of the invention as set forth in any of the claims. Furthermore, it will be clearly understood that if references are made herein to prior art publications, such references do not constitute an endorsement that such publications constitute part of common general knowledge.
[0028] Reference Figure 1The diagram generally shows a pistol-shaped multi-function handheld power tool 10, which has a handle 12 for the operator's hand to hold, and a motor housing 11 extending from the top of the handle 12 to define an internal space for housing a motor 11a, which generates and transmits torque from a motor shaft 28. A transmission / gear housing 19 is located at the front of the motor housing and partially surrounds a portion of the planetary transmission 25 and the clutch mechanism 30. The transmission / gear housing 19 has a forward-extending cylindrical extension 21 that partially surrounds a portion of the tool's hammer mechanism 40. A clutch / mode selection collar 18 is rotatably positioned around the gear housing extension 21 and operated by the user to select between operating modes of the multi-function handheld power tool 10. A chuck 16 is rotatably mounted to the output shaft 20 near the front end of the tool 10 adjacent to the collar 18 and has a cutter head receiving hole 17 for accommodating interchangeable cutter heads. Torque is transmitted from the motor shaft 28 to the chuck 16 via the transmission 25, clutch mechanism 30, and output shaft 20. A power switch 15 is located on the handle 12 and accessible to the operator to turn the motor 11a on and off. The motor 11a can be powered by a battery housed in a battery receiver 14 located at the lower distal end 13 of the handle 12. When the operator presses the power switch 15, power is supplied from the battery to the motor 11a to generate torque at the motor output 28. The output torque is transmitted along the tool's output axis between the motor output 28 and the chuck 16 via the transmission 25, clutch 30, and tool spindle 20. A single clutch / mode setting collar 18 can be rotated by the user to select between several limited torque functions or unlimited torque functions, such as a "screwdriver mode," a "drill-only mode," or a "hammer drill mode."
[0029] The multi-step clutch mechanism 30 provides a limited torque output to the shaft 20, or can be deactivated / locked to provide an unlimited torque output. For example... Figures 2 to 4As shown, the multi-step clutch mechanism 30 includes a clutch washer 31 and a sleeve 32, which is axially and rotatably adjustable in response to rotation of the clutch / mode selection collar 18 by the user. The clutch sleeve 32 has a bore with an inner periphery including threads 23 that cooperate with external threads 22 on the outer periphery of the gear housing extension 21. The clutch sleeve 32 is additionally rotatably fixed to the mode selection collar 18. The clutch / mode selection collar 18 can be rotatably adjusted by the user of the multi-tool to select a specific clutch setting or torque setting for the handheld tool, and to allow the tool to switch between screwdriver operation mode, drill-only operation mode, and hammer drill operation mode. When the collar 18 rotates, it rotates the clutch sleeve 32, causing the clutch sleeve 32 to travel axially along the gear housing extension 21 via the interaction of the threads 23 / 22. The clutch coil spring 34 is arranged between the clutch washer 31 and the clutch sleeve 32, such that it pulls the clutch washer 31 away from the clutch sleeve 32 toward the gear transmission 25 rearward (e.g., Figure 2 (As shown, it is offset to the left).
[0030] The clutch mechanism 30 has multiple clutch settings or torque settings in "screwdriver mode," ranging from a first position where the clutch sleeve 32 is axially furthest from the clutch washer 31 to a second position where the clutch sleeve 32 is axially closest to the clutch washer 31. At the first position, axially furthest, the clutch spring 34 is in its minimum compression or preload state, while at the second position, axially closest, the clutch spring 34 is in its maximum compression or preload state. Rotating the clutch sleeve 32 via the clutch / mode selection collar 18 adjusts the preload of the clutch spring 34 acting on the clutch washer 31, thereby adjusting the torque limit, as described in further detail below. When the clutch sleeve 32 is closest to the clutch washer 31, thus applying the maximum preload to the spring 34, the tool is in its drill mode.
[0031] The clutch mechanism 30 also includes a plurality of driven elements, such as cylindrical pins 36 and balls 37. The plurality of cylindrical pins 36 are received within corresponding plurality of circumferentially spaced axial holes 24 in the transmission housing 19. Clutch faces 38 / 39 are defined on the final stage outer ring gear 26 of the transmission 25. A plurality of balls 37 are positioned between the corresponding pins 36 and the clutch faces 38 / 39. The outer ring gear 26 is positioned in the transmission housing 19 of the hammer drill and is part of the third planetary stage of the transmission 25. The clutch faces 38 / 39 include a plurality of ramps 38 on which the balls 37 ride when the clutch mechanism 30 is engaged. The ramps 38 extend axially by a distance D1 from the linear surface portion 39 of the clutch faces 38 / 39, such that the balls 37 must be able to translate axially away from the linear surface portion 39 by at least an axial distance D1 so that the balls ride on the ramps 38, thereby disengaging the multi-tool 10. Therefore, for the clutch to operate, the axial distance D2 between the clutch sleeve 32 and the clutch washer 31 must be greater than the distance D1 between the ramp 38 and the linear surface portion 39 of the clutch face. This allows the clutch washer 31 to translate toward the clutch sleeve 32 when the ball 37 rides on the ramp 38.
[0032] exist Figure 4 In the "screwdriver mode" operation where D2 is greater than D1, torque is transmitted from the motor output 28 through the transmission 25 to the spindle 20. During this time, the outer ring gear 26 of the transmission 25 remains stationary relative to the transmission housing 19 due to the preload applied to the clutch surfaces 38 / 39 by the clutch spring 34, clutch washer 31, pin 36, and ball 37. When, for example, a fastener is tightened to a specific torque, a corresponding reaction torque is applied to the spindle 20, causing a decrease in the rotational speed of the spindle 20. When the reaction torque exceeds the torque limit set by the mode selection / clutch collar 18 and clutch sleeve 32, the motor torque is transmitted to the outer ring gear 26, causing it to rotate relative to the transmission housing 19, thereby engaging the clutch mechanism 30 to disengage the tool by transferring motor torque from the spindle 20. As a result, and because the distance D2 is greater than the first axial distance D1, the ball 37 is allowed to translate axially away from the linear portion 39 of the clutch face far enough to allow the ball 37 to ride up and down the ramp 38, thereby causing the clutch washer 31 to reciprocate along the transmission housing 19 against the bias of the spring 34 between the clutch sleeve 32 and the clutch washer 31. By rotating the clutch / mode collar 18, the clutch sleeve 32 is brought to the first position where the clutch sleeve 32 is axially furthest from the clutch washer 31 (e.g., ...). Figure 4The clutch operating torque is set by axially moving the clutch sleeve 32 between a second position (where distance D2 is greater than distance D1) and the clutch washer 31. The closer the clutch sleeve 32 is to the clutch washer 31, the greater the preload of the clutch spring 34, and correspondingly, the higher the clutch operating torque.
[0033] exist Figure 5 In the "drill only" operation shown, the clutch sleeve 32 is further adjusted to be adjacent to but not engaged with the clutch washer 31, such that the distance D2 is less than D1. This prevents the ball 37 from riding on the ramp 38 and locks the clutch mechanism 30. The motor can then output maximum torque to the spindle 20. Note that in Figure 5 For clarity, spring 34 is omitted, but it will be under a high preload.
[0034] exist Figure 5 In the "hammer drill" mode of operation shown, the clutch sleeve 32 is further adjusted to engage the clutch washer 31 and the distance D2 is zero, so that there is no gap between the clutch sleeve 32 and the clutch washer 31, preventing the ball 37 from riding on the ramp 38 with an axial length D1. Therefore, in the "hammer drill" mode, the clutch mechanism 30 is locked, and the motor is allowed to output maximum torque to the spindle 20. Note that in Figure 6 For clarity, spring 34 is omitted, but it will be under high preload. In hammer mode, the spindle is also allowed to reciprocate axially with a hammer action. See below for reference. Figure 2 and Figures 7 to 9 This will be described further.
[0035] In the attached diagram Figures 7 to 9 The hammer mechanism 40 of the multi-tool 10 is shown. Figure 2 The hammer mechanism 40 includes: a first ratchet 41 coupled to rotate with the spindle 20; a second ratchet 42 rotatably and axially fixed to the drive housing 19 of the hammer drill; and hammer locking mechanisms 43, 44, 45, and 46 for selectively inhibiting engagement of ratchet 41 and 42 when the multi-tool 10 is in "screwdriver mode" or "drill-only mode," otherwise ratchet engagement would exert axial reciprocating motion on the spindle 20. The hammer locking mechanism includes a ring 43 coupled to rotate with and within a clutch / mode collar 18. The ring 43 has a plurality of radially outwardly extending recesses 44. The hammer locking mechanism also includes a plurality of symmetrically arranged axial arms 45, each having a radially outwardly extending tab 46. These arms extend from a hub coupled to move axially but not rotationally with the spindle 20.
[0036] like Figure 7As shown, when the mode collar 18 and the locking ring 43 are rotated to the corresponding position for either the "screwdriver mode" or the "drill-only mode," the tab 46 of the arm 45 is misaligned with the recess 44. In response to the spindle 20 pressing against the workpiece, the arm tab 46 abuts against the locking ring 43 and interferes with the backward sliding movement of the spindle 20, thereby inhibiting the contact between the ratchet wheels 41 and 42, thus activating the hammer locking mechanism 40 and inhibiting the reciprocating motion of the spindle 20. However, as Figure 8 As shown, when the mode collar 18 and the locking ring 43 are rotated to the corresponding position for the "hammer drill mode", the arm tab 46 aligns with the recess 44 within the locking ring 43, thereby allowing the arm tab 46 to pass through the recess 44 during the rearward sliding movement of the spindle 20. This allows the ratchet wheels 41, 42 to contact each other to apply an impact reciprocating motion to the spindle 20, thereby deactivating the hammer locking mechanism 40.
[0037] Advantageously, the use of a single mode setting collar provides users with a quick and easy means of mode setting. This single mode setting collar can be rotated to one of multiple positions to engage two or more torque-limited clutch screw-tightening modes, or unlimited torque drill modes or hammer drill modes. This also ensures that the user can only select a single operating mode without conscious thought; for example, the user cannot activate the torque-limited clutch mode while still in drill or hammer drill mode, which might not be the case if the hammer and drill mode selector is disengaged from the torque clutch setting collar.
Claims
1. A multi-functional handheld power tool, comprising: A motor housing and a motor located inside the housing, the motor having a motor output section, and a reduction gear installed to the motor output section so as to rotate together with the motor output section; A configurable clutch is connected to the reduction gear to transmit torque from the reduction gear to the output spindle connected to the chuck; A transmission housing connected to the motor housing, having a first housing portion connected to the motor housing and a second housing portion extending from the first housing portion toward the chuck, wherein at least a portion of the reduction gear and the clutch are located within the first housing portion of the transmission housing; A setting collar is rotatably mounted on the second housing portion of the transmission housing and is rotatable between a plurality of predetermined angular positions, at least one of which corresponds to the tool’s unrestricted torque first operating mode and the remaining positions correspond to different torque output levels of the tool’s restricted torque second operating mode. The configurable clutch includes: a clutch face having a plurality of clutch ramps extending a fixed axial distance from a linear portion of the clutch face; a clutch washer; and a clutch sleeve rotatably positioned axially about a second housing portion of the transmission housing and positioned at a variable axial distance from the clutch washer between the set collar and the second housing portion of the transmission housing; a clutch spring biased between the clutch sleeve and the clutch washer; and a follower positioned between the clutch face and the clutch washer, wherein... The clutch sleeve is rotatably fixed to and rotatable with the setting collar to move axially on the second housing portion of the transmission housing, such that the variable axial distance depends on a corresponding predetermined angular position among a plurality of predetermined angular positions of the setting collar, wherein the fixed axial distance is greater than the variable axial distance in at least one angular position of the setting collar corresponding to the first unrestricted torque operating mode of the tool, and the variable axial distance is greater than the fixed axial distance in the remaining predetermined angular positions of the setting collar.
2. The multi-functional handheld power tool as described in claim 1, wherein, At least a second predetermined angular position of the setting collar corresponds to the tool's unrestricted torque third operating mode, wherein, in the second predetermined angular position of these predetermined angular positions, the fixed axial distance is greater than the variable axial distance.
3. The multi-functional handheld power tool as described in claim 2, wherein, In at least one of the first and second predetermined angular positions of the predetermined angular position of the set collar, corresponding to the first or third unrestricted torque operating mode of the tool, a portion of the clutch sleeve engages with a portion of the clutch washer.
4. The multi-functional handheld power tool as described in any one of claims 1 to 3, wherein, The clutch sleeve and the clutch washer are positioned outside the transmission housing. The clutch sleeve is threadedly engaged with the second housing portion of the transmission housing to convert the rotational movement of the clutch sleeve into axial movement along the second housing portion of the transmission housing.
5. The multi-functional handheld power tool as described in claim 4, wherein, The clutch washer is positioned adjacent to the transition between a first housing portion and a second housing portion of the transmission housing, and wherein the driven member includes a pin extending through a hole in the transmission housing.
6. The multi-functional handheld power tool as claimed in any one of claims 1 to 3, further comprising a pair of opposing ratchet discs positioned within a second housing portion of the transmission housing and arranged to selectively apply axial vibration or impact to the output spindle; and a locking mechanism, a portion of which is rotatable with the setting collar, the locking mechanism having engagement positions corresponding to certain angular positions of the setting collar, these angular positions corresponding to different torque output levels of a limited torque second operating mode of the tool; and disengagement positions corresponding to one of a first or second angular position of the setting collar, one of the first or second angular positions corresponding to an unlimited torque first or third operating mode of the tool, wherein... In the engaged position, axial vibration or impact on the output spindle is suppressed, while in the disengaged position, axial vibration or impact on the output spindle can be achieved.
7. The multi-functional handheld power tool as described in claim 6, wherein, The locking mechanism includes a ring and an axial arm. The ring is coupled to rotate with the set collar and has a radially outwardly extending recess. The axial arm is coupled to move axially but not rotatably with the output spindle and has a radially outwardly extending tab. In the disengaged position, the radially outwardly extending recess and the radially outwardly extending tab are rotatably aligned, allowing the tab to pass through the recess to allow axial movement of the arm and the output spindle.