Power tool

Abstract

A power tool can include a housing including a motor housing portion, a front housing portion coupled to the motor housing portion, and a handle portion extending from the motor housing portion. The power tool can include a motor supported within the motor housing portion. The power tool can include an output driven by the motor to rotate about an axis, the output extending from the front housing portion. The power tool can include an actuator supported by the handle portion and configured to control operation of the motor. The power tool can include a circuit board supported within a containment region between the actuator and the front housing portion. The power tool can include a vibration isolator positioned on the circuit board and between the circuit board and the housing.

Description

Technical Field

[0001] This utility model relates to power tools including circuit boards. Background Technology

[0002] Power tools often generate vibrations during operation. Power tools also typically include electrical and electronic components such as circuit boards, which are easily damaged or have their lifespan shortened when exposed to vibration. Utility Model Content

[0003] There is a need for a solution to protect the circuit boards of power tools from vibration without significantly increasing the size of the power tools.

[0004] In some aspects, the present invention relates to a power tool comprising: a housing including a motor housing portion, a front housing portion coupled to the motor housing portion, and a handle portion extending from the motor housing portion; a motor supported within the motor housing portion; an output member driven by the motor to rotate about an axis, the output member extending from the front housing portion; an actuator supported by the handle portion and configured to control the operation of the motor; a circuit board supported in a receiving area between the actuator and the front housing portion; and a vibration isolator positioned on the circuit board and between the circuit board and the housing.

[0005] In some respects, the technology described in this utility model relates to power tools, wherein vibration isolators are configured to reduce the transmission of vibrations generated by the operation of the power tool to a circuit board.

[0006] In some respects, the technology described in this invention relates to power tools in which the vibration isolator is made of foam.

[0007] In some respects, the technology described in this invention relates to power tools in which a vibration isolator is compressed between a circuit board and a housing.

[0008] In some respects, the technology described in this utility model relates to power tools in which a vibration isolator is bonded to a circuit board.

[0009] In some respects, the technology described in this invention relates to power tools, wherein the circuit board includes a plurality of semiconductor switching elements.

[0010] In some respects, the technology described in this utility model relates to power tools, wherein a circuit board extends parallel to an axis.

[0011] In some respects, the technology described in this invention relates to power tools, wherein the actuator is a trigger that can move in a direction parallel to the axis to change the operating speed of the motor.

[0012] In some aspects, the technology described in this utility model relates to power tools, wherein the housing includes a clamshell half that defines a motor housing portion and a handle portion for mating, wherein the clamshell half defines an upper wall of a receiving area that extends adjacent to the bottom side of a front housing portion, and wherein a vibration isolator is compressed between a circuit board and the upper wall.

[0013] In some aspects, the present invention relates to a power tool comprising: a housing including a motor housing portion, a front housing portion coupled to the motor housing portion, and a handle portion extending from the motor housing portion; a motor supported within the motor housing portion; an impact mechanism driven by the motor to transmit a rotational impact to an output member extending from the front housing portion, the output member being rotatable about an axis; an actuator supported by the handle portion and configured to control the operation of the motor; a circuit board extending parallel to the axis, the circuit board being supported within the housing and including a first side facing the impact mechanism and a second side facing the actuator; and a vibration isolator positioned on the first side of the circuit board.

[0014] In some respects, the technology described in this invention relates to power tools, wherein the vibration isolator is configured to reduce the transmission of vibrations generated by the operation of the power tool to the circuit board.

[0015] In some respects, the technology described in this invention relates to power tools in which the vibration isolator is made of foam.

[0016] In some respects, the technology described in this invention relates to power tools in which a vibration isolator is compressed between a first side of a circuit board and a housing.

[0017] In some respects, the technology described in this utility model relates to power tools in which a circuit board is supported in a receiving area between a front housing portion and an actuator.

[0018] In some aspects, the technology described in this utility model relates to power tools, wherein the housing includes a clamshell half that defines a mating motor housing portion and a handle portion, wherein the clamshell half defines an upper wall of a receiving area that extends adjacent to the bottom side of a front housing portion, and wherein a vibration isolator is compressed between a first side of a circuit board and the upper wall.

[0019] In some respects, the technology described in this utility model relates to power tools, wherein a vibration isolator covers less than 50% of the area on the first side of a circuit board.

[0020] In some aspects, the present invention relates to a power tool comprising: a housing including a clamshell-like half defining a motor housing portion and a handle portion extending from the motor housing portion, the housing further including a front housing portion coupled to the clamshell-like half; a motor supported within the motor housing portion; an output member driven by the motor to rotate about an axis, the output member extending from the front housing portion; an actuator supported by the handle portion and configured to control operation of the motor; a circuit board supported within a receiving area between the actuator and the front housing portion, wherein the clamshell-like half defines an upper wall of the receiving area, the upper wall extending adjacent to the bottom side of the front housing portion; and a vibration isolator located between the circuit board and the upper wall.

[0021] In some respects, the technology described in this utility model relates to power tools, wherein the actuator is a multi-position switch.

[0022] In some respects, the technology described in this invention relates to power tools, wherein the vibration isolator comprises foam compressed between a circuit board and an upper wall.

[0023] In some respects, the technology described in this invention relates to power tools, wherein the actuator is a trigger configured to control the operating speed of a motor. Attached Figure Description

[0024] Figure 1 A perspective view of a power tool is shown.

[0025] Figure 2 It shows Figure 1 A three-dimensional sectional view of a power tool.

[0026] Figure 3 The section cut along line 3-3 is shown. Figure 1 A cross-sectional view of a power tool.

[0027] Figure 4 It shows Figure 1 A magnified 3D view of the circuit board of a power tool.

[0028] Before explaining any embodiment of this utility model in detail, it should be understood that the utility model, in its application, is not limited to the details of the construction and arrangement of the components described in the following description or shown in the drawings. The utility model can have other embodiments and can be practiced or implemented in various ways. Furthermore, it should be understood that the wording and terminology used in this utility model are for illustrative purposes and should not be considered restrictive. Detailed Implementation

[0029] Figure 1An embodiment of a power tool in the form of a rotary impact tool is shown, and more specifically, an impact wrench 10 is shown. The impact wrench 10 includes a housing 14 having a motor housing portion 18, an impact shell or front housing portion 22 coupled to the motor housing portion 18, and a handle portion 26 extending downward from the motor housing portion 18. In the illustrated embodiment, the handle portion 26 and the motor housing portion 18 are defined by mating first and second clamshell halves or housing portions 28a, 28b; however, in other embodiments, the housing 14 may be constructed in other ways.

[0030] See also Figure 1 The clamshell halves 28A and 28B are coupled (e.g., fastened) together at an interface or seam 32. The illustrated housing 14 also includes an end cap 30 coupled to the motor housing portion 18, opposite the front housing portion 22. In other embodiments, the impact wrench 10 may not include a separate end cap, which allows the clamshell halves 28a and 28b to instead define the rear end of the motor housing portion 18. In other embodiments, the front housing portion 22 may be omitted or may be surrounded by the clamshell halves 28a and 28b.

[0031] The illustrated impact wrench 10 includes a battery 36, which is removably coupled to a battery socket 38 in the handle portion 26. A motor 42 is supported within a motor housing portion 18 and receives power from the battery 36 via connectors, pads, and / or battery terminals in the battery socket 38 when the battery 36 is coupled to it. In the illustrated embodiment, the handle portion 26 of the clamshell halves 28a, 28b may be covered or surrounded by a gripping portion 44, which may be molded over the handle portion 26.

[0032] Battery 36 may be a power tool battery pack (e.g., a 12-volt rechargeable battery pack) typically used to power power tools such as drills, chainsaws, etc. Battery 36 may include lithium-ion (Li-ion) battery cells. The 12-volt nominal output voltage of battery 36 provides an optimal balance between weight / size and power in the illustrated impact wrench 10; however, batteries with other nominal voltages may be used in other embodiments.

[0033] See Figures 2-3 In the illustrated embodiment, motor 42 is positioned adjacent to end cap 30 within motor housing portion 18. The illustrated motor 42 is a brushless direct current (“BLDC”) motor having a stator and a rotor or output shaft 54, the rotor or output shaft 54 ​​extending through the stator and rotatable relative to the stator about a rotation axis A1. In other embodiments, motor 42 may be another type of motor, such as a brushed motor, an external rotor motor, etc.

[0034] The gear assembly 46, supported by the motor housing portion 18, receives torque from the output shaft 54 ​​of the motor 42 and provides deceleration between the output shaft 54 ​​and the impact mechanism 50. Figure 3 The gear assembly 46 shown includes a pinion 56 coupled to the output shaft 54 ​​of the motor 42, a plurality of planetary gears 58 meshing with the pinion 56, and a ring gear 62 meshing with the planetary gears 58 and rotatably fixed within the motor housing portion 18. The planetary gears 58 are coupled to the camshaft 66 of the impact mechanism 50, which allows the camshaft 66 to function as a planet carrier. The ring gear 62 shown is directly supported by clamshell halves 28A, 28B; however, the ring gear 62 may alternatively be supported in other ways (e.g., within a gearbox).

[0035] Impact mechanism 50 is configured to convert a constant rotational force or torque provided by motor 42 and gear assembly 46 into intermittent application of impact rotational force or torque. The illustrated impact mechanism 50 includes a camshaft 66, a hammer 70, a spring 74, and an anvil 78. Camshaft 66 is configured to transmit rotation from planetary gear 58 to hammer 70 and includes a cam groove 82 in which a corresponding cam ball 86 is received. Hammer 70 is configured to reciprocate axially along camshaft 66 and apply periodic rotational impacts to anvil 78 in response to rotation of camshaft 66. Spring 74 biases hammer 70 axially toward anvil 78 along axis of rotation A1. Anvil 78 extends from front housing portion 22 and defines the output of impact wrench 10 rotatable about axis A1. The illustrated anvil 78 has a distal end or drive member to which a tool element (e.g., socket, not shown) can be coupled for performing work on a workpiece (e.g., fastener).

[0036] See Figure 2 and Figure 3 The impact wrench 10 also includes a trigger 90, a multi-position switch 94, a first circuit board 98, and a second circuit board 102. The trigger 90 and multi-position switch 94, also referred to as actuators, are supported by the handle portion 26 of the housing 14 and configured to control the operating characteristics of the motor 42 based on user input. Specifically, the trigger 90 can be moved by the user along a trigger axis A2 parallel to the rotation axis A1 to energize and de-energize the motor, and in some embodiments, controls the rotational speed of the motor 42 (e.g., proportional to the movement of the trigger 90 along the trigger axis A2). The multi-position switch 94 can be moved by the user to a plurality of positions along a multi-position switch axis A3 orthogonal to the rotation axis A1 and the trigger axis A2 to control the desired rotational direction of the motor 42.

[0037] In the illustrated embodiment, a first circuit board 98 is supported within the motor housing portion 18, adjacent to the front end of the motor 42. The illustrated first circuit board 98 extends perpendicular to the rotation axis A1 and includes one or more Hall effect sensors, which provide feedback for controlling the motor 42. In some embodiments, the first circuit board 98 may be omitted, and the motor 42 may be configured for sensorless control via a second circuit board 102.

[0038] See Figure 3 The second circuit board 102 extends parallel to the rotation axis A1 and is positioned in a receiving area 101 between the upper end of the handle portion 26 and the bottom side of the front housing portion 22 (and in the illustrated embodiment, between the trigger 90 and the front housing portion 22). In the illustrated embodiment, the circuit board 102 is held in a plurality of recesses 106 formed on the inner surface of each clamshell half 28A, 28B. The recesses 106 support the second circuit board 102 and restrict its movement in a direction parallel to the rotation axis A1. The second circuit board 102 is electrically connected to terminals (not shown) of the motor 42, the trigger 90, and the battery socket 38. In the illustrated embodiment, the second circuit board 102 includes a plurality of semiconductor switching elements (e.g., MOSFETs, IGBTs, etc.), one or more microprocessors, machine-readable non-transitory memory elements, and other electrical or electronic components for providing operational control to the impact wrench 10. Additionally, the second circuit board 102 may be at least partially encapsulated in a potting material (i.e., a transparent epoxy polymer) applied to the selected area or to the selected electrical or electronic components.

[0039] like Figure 4 As shown, the second circuit board 102 further includes a first side 108 facing the impact mechanism 50 and a second side 112 facing the multi-position switch 94. A vibration isolator 116 is disposed on the first side 108 of the second circuit board 102. The vibration isolator 116 shown is made of a non-conductive elastomer (e.g., foam, rubber, or silicone) and is adhesively bonded to the first side 108. The vibration isolator 116 fills the gap between the first side 108 of the second circuit board 102 and the upper wall 111 of the receiving region 101, which, in the illustrated embodiment, extends adjacent to the bottom side of the front housing portion 22. In some embodiments, the vibration isolator 116 may be compressed between the upper wall 111 and the second circuit board 102, allowing the vibration isolator 116 to bias the second circuit board 102 toward the multi-position switch 94.

[0040] In operation, the cam ball 86 engages with the hammer 70, and as the hammer 70 engages with the anvil 78 and the camshaft 66 continues to rotate, the movement of the cam ball 86 within the cam groove 82 allows the hammer 70 to move axially relative to the camshaft 66. The axial movement of the hammer 70 compresses the spring 74, and when the hammer 70 retracts a sufficient distance away from the anvil 78, the spring 74 then releases its stored energy to propel the hammer 70 forward and cause it to rotate. The hammer 70 then strikes the anvil 78 to transmit torque to it, and this process is repeated.

[0041] The elastic properties of the vibration isolator reduce the transmission of vibrations generated by the impact mechanism 50 on an axis orthogonal to the rotation axis A1 during operation of the impact wrench 10. The pressure applied to the second circuit board 102 by the vibration isolator 116 also reduces any oscillations of the circuit board 102 that may be caused by such vibrations. By limiting the exposure of the second circuit board 102 to vibration, the impact wrench 10 can have a longer lifespan. In the illustrated embodiment, the surface area covered by the vibration isolator 116 is less than 50% of the total surface area of ​​the second circuit board 102 and is located only on the first side 108. In other embodiments, the vibration isolator 116 may cover a larger portion of the second circuit board 102 and may be directly attached to the electrical or electronic components of the second circuit board 102. Furthermore, in other embodiments, both the first side 108 and the second side 112, or only the second side 112, may include the vibration isolator 116 bonded to the second circuit board 102 and in contact with a portion of the housing 14.

[0042] The various features and aspects of this utility model are described in the appended claims.

Claims

1. A power tool, characterized in that, include: A housing, the housing including a motor housing portion, a front housing portion coupled to the motor housing portion, and a handle portion extending from the motor housing portion; A motor, which is supported within the motor housing portion; An output element, which is driven by the motor to rotate about an axis, extends from the front housing portion; An actuator, which is supported by the handle portion and configured to control the operation of the motor; A circuit board, which is supported in a receiving area between the actuator and the front housing portion; and A vibration isolator, which is positioned on the circuit board and between the circuit board and the housing.

2. The power tool as described in claim 1, characterized in that, The vibration isolator is configured to reduce the transmission of vibrations generated by the operation of the power tool to the circuit board.

3. The power tool as described in claim 1 or 2, characterized in that, The vibration isolator is made of foam.

4. The power tool according to any one of the preceding claims, characterized in that, The vibration isolator is compressed between the circuit board and the housing.

5. The power tool according to any one of the preceding claims, characterized in that, The vibration isolator is bonded to the circuit board.

6. The power tool according to any one of the preceding claims, characterized in that, The circuit board includes a plurality of semiconductor switching elements.

7. The power tool according to any one of the preceding claims, characterized in that, The circuit board extends parallel to the axis.

8. The power tool according to any one of the preceding claims, characterized in that, The actuator is a trigger that can move in a direction parallel to the axis to change the operating speed of the motor.

9. The power tool according to any one of the preceding claims, characterized in that, The housing includes a clamshell half that defines the mating of the motor housing portion and the handle portion, wherein the clamshell half defines an upper wall of the receiving area, the upper wall extending adjacent to the bottom side of the front housing portion, and wherein the vibration isolator is compressed between the circuit board and the upper wall.

10. A power tool, characterized in that, include: A housing, the housing including a motor housing portion, a front housing portion coupled to the motor housing portion, and a handle portion extending from the motor housing portion; A motor, which is supported within the motor housing portion; An impact mechanism, driven by the motor, transmits a rotational impact to an output member extending from the front housing portion, the output member being rotatable about an axis. An actuator, which is supported by the handle portion and configured to control the operation of the motor; A circuit board extending parallel to the axis, the circuit board being supported within the housing and including a first side facing the impact mechanism and a second side facing the actuator; and A vibration isolator, which is positioned on the first side of the circuit board.

11. The power tool as claimed in claim 10, characterized in that, The vibration isolator is configured to reduce the transmission of vibrations generated by the operation of the power tool to the circuit board.

12. The power tool as claimed in claim 10 or 11, characterized in that, The vibration isolator is made of foam.

13. The power tool as claimed in any one of claims 10-12, characterized in that, The vibration isolator is compressed between the first side of the circuit board and the housing.

14. The power tool as claimed in any one of claims 10-13, characterized in that, The circuit board is supported in the receiving area between the front housing portion and the actuator.

15. The power tool as claimed in claim 14, characterized in that, The housing includes a clamshell half that defines the mating of the motor housing portion and the handle portion, wherein the clamshell half defines an upper wall of the receiving area, the upper wall extending adjacent to the bottom side of the front housing portion, and wherein the vibration isolator is compressed between a first side of the circuit board and the upper wall.

16. The power tool as claimed in any one of claims 10-15, characterized in that, The vibration isolator covers less than 50% of the area on the first side of the circuit board.

17. A power tool, characterized in that, include: A housing, the housing including a clamshell-shaped half that defines a motor housing portion and a handle portion extending from the motor housing portion, the housing further including a front housing portion coupled to the clamshell-shaped half; A motor, which is supported within the motor housing portion; An output element, which is driven by the motor to rotate about an axis, extends from the front housing portion; An actuator, which is supported by the handle portion and configured to control the operation of the motor; A circuit board, the circuit board being supported in a receiving area between the actuator and the front housing portion, wherein the clamshell half defines an upper wall of the receiving area, the upper wall extending adjacent to the bottom side of the front housing portion; and A vibration isolator, the vibration isolator being positioned between the circuit board and the upper wall.

18. The power tool as claimed in claim 17, characterized in that, The actuator is a multi-position switch.

19. The power tool as claimed in claim 17 or 18, characterized in that, The vibration isolator comprises foam compressed between the circuit board and the upper wall.

20. The power tool as claimed in any one of claims 17-19, characterized in that, The actuator is a trigger configured to control the operating speed of the motor.

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