CN-114843122-B - Trigger switch

CN114843122BCN 114843122 BCN114843122 BCN 114843122BCN-114843122-B

Abstract

The invention provides a trigger switch, which can detect the pressing amount of a trigger receiving a pressing operation in a non-contact manner and exclude the influence of an external environment magnetic field. The Trigger Switch (TS) has a first conductive plate (40) (movable electrode) that moves with the movement of the trigger (1) caused by a pressing operation, and a second fixed electrode (51) (fixed electrode) that is disposed in the vicinity of the movement range of the first conductive plate (40) with a gap therebetween and that forms a capacitance with the first conductive plate (40). The capacitance of the capacitor formed by the first conductive plate (40) and the second fixed electrode (51) of the Trigger Switch (TS) changes with the movement of the first conductive plate (40).

Inventors

FUJIWARA TAKUMI
SHIMIZU RYOJI
FUJIO KOHEI
ISHII AKIHIRO
KOYAMA TAIKI
Front Tian Yizhi

Assignees

欧姆龙株式会社

Dates

Publication Date: 20260508
Application Date: 20220112
Priority Date: 20210202

Claims (5)

1. A trigger switch for a power tool having a trigger that moves upon receiving a pressing operation, the trigger switch comprising: an operation member that receives an operation and operates; A movable electrode which is plate-shaped along a movement direction of the trigger and moves along with the movement of the trigger due to a pressing operation; a fixed electrode having a plate shape along a movement direction of the trigger, and disposed in the vicinity of a movement range of the movable electrode to form a capacitance with the movable electrode; A sub movable electrode that moves in response to the operation of the operation member; A sub-fixed electrode that forms a capacitance with the sub-movable electrode when the sub-movable electrode is located in the vicinity; the movable electrode is isolated from the fixed electrode, The capacitance of the capacitor formed by the movable electrode and the fixed electrode changes with the movement of the movable electrode, By moving with the operation of the operation member, the sub movable electrode moves as a movement range between a position where a capacitance is formed with the sub fixed electrode and a position where a capacitance is not formed.
2. The trigger switch of claim 1, wherein, The fixed electrode is formed in a shape that varies in accordance with the position of the movable electrode within a movement range and the electrode area that forms the capacitor.
3. The trigger switch of claim 2, wherein, The fixed electrode is formed in a shape in which an electrode area forming a capacitance gradually increases along a moving direction based on a pressing operation.
4. The trigger switch according to claim 1 to 3, The assembly can be performed in an electric device having a driving portion driven based on an electric signal, Also has an output part for outputting an electric signal for driving the driving part, The output unit outputs an electric signal for driving the driving unit, with an output corresponding to the capacitance of the capacitor formed by the movable electrode and the fixed electrode.
5. The trigger switch according to claim 1 to 3, The assembly can be performed in an electric device having a driving portion driven based on an electric signal, Also has an output part for outputting an electric signal for driving the driving part, The output section performs the following actions, Outputting an electric signal for driving the driving unit at an output corresponding to the capacitance of the capacitor formed by the movable electrode and the fixed electrode, An electric signal indicating a driving method of the driving unit is output based on the capacitance of the capacitor formed by the sub movable electrode and the sub fixed electrode.

Description

Trigger switch Technical Field The present invention relates to a trigger switch that moves in response to a pressing operation of a trigger. Background A trigger switch that receives a pressing operation to control the operation of the power tool is in use. For example, in patent document 1, a trigger switch that detects the amount of depression of a trigger using a magnetic sensor has been disclosed. The trigger switch described in patent document 1 can realize an increase in lifetime by detecting the amount of depression of the trigger in a noncontact manner by using a magnetic sensor. Prior art literature Patent literature Patent document 1 International publication No. 2020/231974 Disclosure of Invention Technical problem to be solved by the invention However, when the trigger switch using the magnetic sensor described in patent document 1 is assembled and operated in a power tool, malfunction may occur due to a change in the magnetic field of the external environment. For example, the trigger switch of the electric tool may be used in the vicinity of a source of generation of magnetic force lines such as a crane using a strong electromagnet for gripping scrap iron, a motor inside the self-apparatus, and the like, and thus, erroneous operation may occur due to magnetic force lines generated from the source of generation. The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a trigger switch capable of detecting the pressing amount of a trigger in a noncontact manner and not being affected by a magnetic field of an external environment. Technical scheme for solving technical problems In order to solve the above-described problems, the trigger switch according to the present application is a trigger switch having a trigger that moves in response to a pressing operation, and is characterized by comprising a movable electrode that moves in response to the movement of the trigger caused by the pressing operation, and a fixed electrode that is disposed in the vicinity of the movement range of the movable electrode and forms a capacitance with the movable electrode, wherein the capacitance of the capacitance formed by the movable electrode and the fixed electrode changes in response to the movement of the movable electrode. The trigger switch is characterized in that the fixed electrode is formed in a shape that changes an electrode area forming a capacitor according to a position of the movable electrode in a movement range. Further, the trigger switch is characterized in that the fixed electrode is formed in a shape in which an electrode area forming the capacitor gradually increases along a moving direction by the pressing operation. The trigger switch is characterized by further comprising an operation member that is operated in response to an operation, a sub-movable electrode that moves in response to the operation of the operation member, and a sub-fixed electrode that forms a capacitance with the sub-movable electrode when the sub-movable electrode is located in the vicinity thereof, wherein the sub-movable electrode moves as a movement range between a position where the sub-fixed electrode forms a capacitance and a position where the sub-movable electrode does not form a capacitance in response to the movement of the operation member. The trigger switch may be incorporated into an electric device having a driving unit that is driven by an electric signal, and further includes an output unit that outputs the electric signal that drives the driving unit, wherein the output unit outputs the electric signal that drives the driving unit at an output corresponding to the capacitance of a capacitor formed by the movable electrode and the fixed electrode. The trigger switch of the present application changes the electrostatic capacity according to the pressing operation. ADVANTAGEOUS EFFECTS OF INVENTION The trigger switch of the present invention includes a movable electrode that moves in response to a pressing operation of a trigger, and a fixed electrode that forms a capacitance with the movable electrode, wherein the capacitance of the capacitance formed by the movable electrode and the fixed electrode changes in response to the movement of the movable electrode. Therefore, the trigger switch of the present invention can detect the amount of pressing of the trigger by the electrostatic capacity, and thus has a good effect of eliminating the influence of the external environmental magnetic field. Drawings Fig. 1 is a schematic perspective view showing an example of the appearance of a trigger switch according to the present application. Fig. 2 is an exploded perspective view schematically showing an example of the trigger switch according to the present application. Fig. 3 is a schematic side view showing an example of the trigger switch according to the present application. Fig. 4A is a schematic plan view showing an example of t