Switch mechanism

Abstract

Switch mechanism The device (401) for providing a switch mechanism includes a housing (402) and a pressure-sensitive device (403) attached to the housing. An actuator (405) is movably connected to the housing such that the actuator can move toward and away from the pressure-sensitive device along an axis (406). The resilient member (406) has a first end (407) connected to the actuator and a second end (408) connected to the pressure-sensitive device.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to Chinese Utility Model Patent No. ZL2019 22 194 117.9, filed on December 13, 2019, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] The present invention relates to an apparatus for providing a switch mechanism, a power tool and a method for operating a power tool. Power tools, such as power drills or power screwdrivers, are often provided in a handheld format and are utilized with an operating switch that provides an on / off mechanism or a variable switch that allows adjustment of the rotational speed of the work head of the power tool. These types of power tools typically have a housing that can be grasped and held by an operator, and often have a power source such as a battery located at the bottom of the housing. An input device such as a push button is typically provided on the exterior of the housing so that it can be pressed by the operator. A speed control switch is connected to the input device to operate the speed of the work head. Summary of the Invention [Problem to be solved by the invention]

[0003] Conventional power tool switches of this type utilize a reed switch having contacts and a resistor plate, the resistance being controlled by adjusting the position of the contacts on the resistor plate. The present invention aims to solve the problem that repeated wear on the contacts and resistor plates during use can lead to switch failure. [Means for solving the problem]

[0004] [Brief description of the invention] According to a first aspect of the present invention, there is provided a method for producing a pressure sensing device comprising: a housing; a pressure sensing device mounted to said housing, said pressure sensing device comprising a resistive pressure sensor responsive to a force applied thereto; and a first actuator movably connected to said housing such that the first actuator can move along an axis toward and away from said pressure sensing device. ; a first elastic member having a first end connected to the first actuator and a second end connected to the pressure sensitive device; further comprising a second actuator, a first end of said second actuator abutting said pressure sensitive device; , an apparatus is provided that provides a switch mechanism.

[0005] According to a second aspect of the present invention, Regarding the first aspect A method of operating a power tool including a device is provided, comprising: applying a force to the first actuator movably connected to the housing of the device; moving the first actuator to compress the first resilient member and connect the first resilient member to the pressure-sensitive device; transmitting the force to the pressure-sensitive device; determining a change in an electrical signal from the pressure-sensitive device; and varying an output of the power tool in response to the change in the electrical signal. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 shows an operator operating a power tool. [Figure 2] FIG. 2 is a schematic diagram of a power tool. [Figure 3] FIG. 3 is an exploded view of the pressure sensing device. [Figure 4] FIG. 4 is a cross-sectional diagram of an apparatus providing a switch mechanism. [Figure 5] FIG. 5 is a cross-sectional schematic view of the device of FIG. [Figure 6] FIG. 6 shows the device of FIG. 5 in a compressed configuration after application of a force. [Figure 7] FIG. 7 is a diagram showing a method of operating a power tool incorporating the device described above. [Figure 8] FIG. 8 shows a further embodiment of an apparatus for providing a switching mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0007] Embodiments of the present invention will now be described, by way of example only, with reference to the drawings. The detailed embodiments illustrate the best mode known to the inventors and support the invention as claimed. However, they are merely exemplary and should not be used to interpret or limit the scope of the claims. Their purpose is to provide instruction to those skilled in the art. Elements and processes distinguished by ordinal phrases such as "first" or "second" do not necessarily define any order or ranking.

[0008] [Detailed Description of the Invention] (Figure 1) 1 shows a power tool 101, in this case a power drill, configured to be held in the hand of an operator 102 and operated by an input device 103 including push buttons. In use, an operator 102 operates the power tool 101 by applying a force to an input device 103 that enables rotation of a drill bit 104 . In conventional applications, the input device 103 acts as a switch to turn on / off the rotation of the drill bit 104. However, the present invention provides an improved input device 103 that allows an operator to control the rotation of the drill 104 via the input device 103.

[0009] (Figure 2) FIG. 2 shows a schematic diagram of a power tool 101 according to the present invention. In an embodiment, the power tool 101 comprises an electrical circuit 201 connected to a pressure sensitive device 202 which is connected to the input device 103 . The electrical circuit 201 is further connected to the drill bit 104 of the power tool 101 so that a signal can be sent to the drill bit 104 indicating its rotation. In an embodiment, when the operator 102 applies force to the input device 103, pressure is applied to the pressure sensitive device 202, which communicates with the electrical circuit 201, causing a signal to be sent from the electrical circuit 201 to provide an output, such as rotation of the drill bit 104.

[0010] It will be understood that the invention described herein relates to power tools, but is particularly not limited to rotating electric drills and drill bits, and therefore that the devices described herein, and in particular the switch mechanisms, can be utilized in alternative embodiments and alternative power tools, and further, for alternative operations other than rotating the device. For example, in an alternative embodiment, the switch mechanism is incorporated into a power screwdriver that outputs screwdriver rotation in accordance with the invention. In yet another embodiment, the power tool may provide output through hammer movement.

[0011] (Figure 3) FIG. 3 shows an exploded view 202 of an exemplary pressure-sensing device. In an embodiment, the pressure sensitive device 202 is a single point pressure sensor, which in this embodiment is a resistive pressure sensor. In an embodiment, the pressure sensitive device 202 includes a first conductive layer 301 , a second conductive layer 302 and a force sensitive resistive layer 303 . In an embodiment, the force-sensitive resistive layer 303 comprises a quantum tunneling material available under the name of the assignee, Peratec Holdings Limited.

[0012] Conductive layers 301 and 302 each comprise a conductive material, which in one embodiment comprises a carbon ink and / or a silver-based ink. When a force is applied in the direction of arrow 304 , the force is transmitted from conductive layer 301 through force-sensitive resistive layer 303 to conductive layer 302 . The pressure-sensitive resistive layer 303 responds to an applied force resistance Thus, by connecting the pressure sensitive device to an appropriate electrical circuit and measuring the output resistance, the magnitude and / or position of the force can be calculated from the output resistance.

[0013] (Figure 4) FIG. 4 is a cross-sectional diagram of an apparatus providing a switch mechanism. Device 401 comprises a housing 402 and a pressure-sensing device 403 attached to housing 402. In an embodiment, pressure-sensing device 403 includes a resistive pressure sensor, which may be substantially similar to pressure-sensing device 202 described above with respect to FIG. In an embodiment, the housing 402 is provided with a groove 404 configured to receive the pressure sensitive device 403, thereby providing a means for producing a precisely positioned pressure sensitive device 403.

[0014] The device 401 further comprises an actuator 405 movably connected to the housing 402. In an embodiment, the actuator 405 is axially movable towards and away from the pressure sensitive device 403. 412 is configured to move along The device 401 further includes a resilient member 406, which in this embodiment is a spring. The resilient member 406 has a first end 407 connected to the actuator 405 and a second end 408 connected to the pressure-sensitive device 403. The actuator 405 is further connected to an input device 409 which comprises a push button substantially similar to a push button on a conventional power tool.

[0015] In one embodiment, device 401 further comprises a guide rod attached to housing 402 and secured to actuator 405. 410 The guide rod 410 is disposed perpendicular to the pressure surface 305 of the pressure-sensing device 403. The second elastic member 411 is sleeved onto the guide rod 410. In the embodiment, Second The resilient member 411 again comprises a spring and is utilized to increase resilience when a force is applied to the input device 409 . In one embodiment, Second The elastic member 411 is provided between the actuator 405 and the housing 402 .

[0016] (Figure 5) FIG. 5 is a schematic cross-sectional view of the device 401. In an embodiment, when an operator applies force 501 to input device 409 , this force is transmitted to actuator 405 , which moves along an axis in the direction of arrow 502 . The device 401 further comprises a positioning structure 503 which forms part of and is attached to the pressure-sensitive device 403. The positioning structure 503 is configured to receive the resilient member 406 at an end 408. The actuator 405 further comprises a positioning hole 504 at an end 407 in which the resilient member 406 is also disposed. This ensures that the resilient member 406 is securely disposed on the actuator 405, so that as the actuator 405 moves in the direction of arrow 502, the resilient member 406 is substantially held by the actuator 405 and the pressure-sensitive device 403.

[0017] The arrangement 503 is provided on the pressure surface 305 of the pressure sensitive device 403 . The embodiment of Figure 5 further shows a guide rod 410 that is disposed perpendicular to the pressure surface 305 and the pressure sensing device 403. As shown, the guide rod 403 is fixed to the actuator 405 at an end 505. At an end 506 of the guide rod 410, the pressure sensing device 403 includes an opening 507 through which the guide rod 410 is inserted. In this way, the guide rod 410 does not affect the resistance output from the pressure sensing device 403.

[0018] 5, device 401 is shown in a rest position with resilient member 406 and actuator 405 resiliently biased away from pressure-sensitive device 403 by resilient member 406. Resilient member 411, provided between actuator 405 and the housing of device 401, also acts to bias actuator 405 away from pressure-sensitive device 403. Thus, in this rest position, force 501 is not transmitted to pressure sensitive device 403 and no output from pressure sensitive device 403 activates the power tool through its electrical circuitry. When force 501 is applied, an output is produced from the pressure sensitive device as will be further described with respect to FIG.

[0019] (Figure 6) 6 shows a substantially similar view of device 401, in which force 501 is applied to actuator 405 by input device 409. The force applied to actuator 405 is directed to elastic members 406 and 411, which are compressed as shown, and force 501 is transmitted to pressure sensitive device 403. In this manner, changes in the electrical signal from the pressure sensitive device 403 can be recorded by the electrical circuit 201, which can be used to operate the power tool, for example, by indicating the rotational speed of the drill bit 104.

[0020] (Figure 7) FIG. 7 illustrates the operation of a power tool incorporating the device 401 described above. In step 701, a force, such as force 501, is applied to actuator 405. In practice, operator 102 applies a force to input device 409 that communicates to actuator 405. In step 702, the actuator 405 412 7, in the direction of arrow 502, toward pressure-sensitive device 403. This causes elastic member 403 to compress, so that a force is transmitted to pressure-sensitive device 403 in step 703.

[0021] In step 704 , a change in the electrical signal from the pressure sensitive device 403 is determined by the electrical circuit 201 using the change in resistance recorded from the pressure sensitive device 403 . In step 705, the output of the power tool is changed in response to the change in the electrical signal. In this manner, the pressure sensitive device allows changes in applied pressure to affect the speed, rotation or other parameters of the power tool's output.

[0022] (Figure 8) FIG. 8 shows a further embodiment according to the invention. Device 801 provides a switch mechanism suitable for a power tool. In an embodiment, device 801 includes a housing 802 and a pressure sensitive device 803 attached to housing 802. In an embodiment, pressure sensitive device 803 includes a resistive pressure sensor, which in this embodiment is a dual point sensor, meaning that the pressure sensitive device registers pressure applied to two points on the sensing device.

[0023] The device 801 includes a first actuator 804 movably connected to the housing 802 such that the actuator 804 can move along an axis toward and away from the pressure-sensing device 803 in a manner substantially similar to the device 401 embodiment. The device 801 further comprises a first resilient member 805 that is substantially similar to the previously described resilient member 406. The resilient member 805 is thus connected at a first end to the actuator 804 and at a second end to the pressure sensitive device 803.

[0024] In a substantially similar manner, the housing 802 includes a groove 806 configured to receive the pressure-sensitive device 803. The groove 806 is provided in an inner wall of the housing 802. In an embodiment, device 801 includes a guide rod 807 attached to housing 802 and positioned perpendicular to the pressure surface of pressure-sensing device 803. Guide rod 807 is fixed at one end to actuator 804 and at the other end to housing 802. Resilient member 808 is sleeved onto guide rod 807. Actuator 804 is resiliently biased away from pressure-sensing device 803 by resilient members 805 and 808.

[0025] In an embodiment, the device 801 further comprises a further elastic member 809 disposed between the actuator 804 and the pressure sensitive device 803 . A second actuator 810 is also provided, with one end connected to the input device 811 and the opposite end of the actuator 810 abutting the pressure sensitive device 803 . Thus, the device 801 thus includes first and second input devices 811 and 812 that can be operated by the operator 102 . In this embodiment, when a force is applied to the input device 812, the elastic members 805, 808, and 809 compress, simultaneously activating distinct points on the pressure sensitive device 803. This allows the operator 102 greater control over the input device 812.

[0026] When the operator 102 applies a force to the input device 811, pressure is applied to the pressure sensitive device 803 in area 813, thereby providing an alternative response. Thus, the device 801 is given two distinct modes that provide a wider range. The lack of an included elastic member reduces the effort required by the operator 102 when applying a force to the input device 811. However, to increase sensitivity, the input device 812 can be utilized to increase control.

Claims

1. An apparatus for providing a switching mechanism, comprising: Housing included: a pressure sensitive device mounted on the housing, the pressure sensitive device including a resistive pressure sensor responsive to an applied force; a first actuator movably connected to the housing such that the first actuator can move along an axis toward and away from the pressure sensitive device; a first resilient member having a first end connected to the first actuator and a second end connected to the pressure sensitive device; the device providing the switch mechanism further comprises: a second actuator; A first end of the second actuator abuts the pressure-sensitive device. Device.

2. The apparatus of claim 1 , wherein the housing includes a groove configured to receive the pressure-sensing device.

3. 3. The apparatus of claim 2, wherein said groove is provided in an inner wall of said housing.

4. 4. The apparatus of claim 1, wherein the first resilient member comprises a spring.

5. 5. An apparatus according to any one of claims 1 to 4, wherein the pressure sensitive device includes an arrangement configured to receive the first resilient member.

6. 6. The device of claim 5, wherein the first actuator includes a mounting hole, and the first elastic member is disposed within the mounting hole at the first end and within the mounting structure at the second end.

7. 7. The device according to claim 5 or claim 6, wherein the arrangement is provided on a pressure surface of the pressure-sensitive device.

8. 8. The apparatus of claim 1, further comprising a guide rod attached to the housing, the guide rod being oriented perpendicular to a pressure surface of the pressure-sensing device.

9. 9. The apparatus of claim 8, wherein the guide rod is fixed to the first actuator.

10. 10. Apparatus according to claim 8 or claim 9, wherein a second resilient member is sleeved onto the guide rod.

11. 11. The device of claim 1, wherein the first actuator is biased resiliently away from the pressure sensitive device by the first resilient member.

12. 12. The device according to claim 1, further comprising a second elastic member disposed between the first actuator and the housing.

13. 13. The device of claim 12, wherein the first actuator is biased resiliently away from the pressure sensitive device by the second resilient member.

14. 14. The apparatus of claim 12 or claim 13, wherein the second resilient member comprises a spring.

15. 15. The apparatus of any one of claims 1 to 14, further comprising a first input device connected to the first actuator.

16. 10. The apparatus of claim 1, further comprising a second input device connected to the second actuator.

17. 17. The device of any one of claims 1 to 16, further comprising a third elastic member disposed between the first actuator and the pressure sensitive device.

18. 18. An apparatus according to any one of claims 1 to 17, wherein the pressure sensitive device is connected to the electrical circuit of a power tool.

19. A power tool including a device according to any one of claims 1 to 18.

20. A method of operating a power tool including the device of claim 1, comprising: applying a force to the first actuator movably connected to the housing of the device; moving the first actuator to compress the first resilient member and connect the first resilient member to the pressure sensitive device; transmitting the force to the pressure sensitive device; determining a change in an electrical signal from the pressure sensing device; Varying the output of the power tool in response to changes in the electrical signal method.

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