Trigger switch

Abstract

The invention provides a trigger switch capable of improving air tightness of a frame body. The trigger switch includes: a shaft member that receives a press-in operation and moves from a first side to a second side; and a frame housing the second side of the shaft member in a movable manner. The trigger switch includes: a flexible outer tubular member covering the shaft member outside the frame; and a flexible inner tubular member housed inside the frame body and attached to the other end side of the shaft member. The frame body has an insertion hole formed in a front wall portion of a first side, through which the shaft member is inserted, and a vent hole formed in a rear wall portion of a second side. The end of the first side of the outer tubular member is sealed at the first side of the shaft member, and the opening of the second side is in close contact with the periphery of the insertion hole. The opening in the first side of the inner tubular member is sealed, and the opening in the second side is in close contact with the periphery of the vent hole.

Description

Technical Field

[0001] The present invention relates to a trigger switch comprising: a shaft member on which a trigger cover for receiving a pressing operation is mounted; and a frame body through which the shaft member is inserted. Background Art

[0002] A trigger switch is used to operate power tools. It consists of a trigger cap that receives a push from the operator, a shaft (plunger) with the trigger cap attached to one end, and a housing that houses the other end of the shaft. Because the housing houses the contact components that open and close the circuit, the housing must be airtight for waterproofing and dustproofing.

[0003] When an operator presses the trigger switch, the shaft member is pushed into the frame and then pushed out of the frame according to the stroke of the pressing operation. The movement of the shaft member relative to the frame causes changes in the air pressure within the frame. This change in air pressure within the frame adversely affects airtightness, such as waterproofing and dustproofing. Therefore, various countermeasures have been proposed (for example, see Patent Document 1).

[0004] [Prior art literature]

[0005] [Patent Document]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-054310 Summary of the Invention

[0007] [Problems to be solved by the invention]

[0008] As described above, the trigger switch is required to have an airtight housing.

[0009] The present application is completed in view of the above situation, and an object of the present application is to disclose a trigger switch capable of improving airtightness.

[0010] [Technical means to solve the problem]

[0011] In order to solve the above-mentioned problem, the trigger switch disclosed in the present application includes: a shaft member, a trigger cover that is moved from the first side to the second side by a pressing operation and is installed on the first side; and a frame body that accommodates the second side of the shaft member in a movable manner. The trigger switch is characterized in that it includes: a flexible outer tubular member that covers the shaft member on the outside of the frame body; and a flexible inner tubular member that is accommodated inside the frame body and installed on the second side of the shaft member, the frame body having an insertion hole for inserting the shaft member formed on the first wall portion on the first side and a ventilation hole formed on the second wall portion on the second side, the outer tubular member having an end portion on the first side that is sealed on the first side of the shaft member, and an opening on the second side that is in close contact with the periphery of the insertion hole, and the inner tubular member having an end portion on the first side that is sealed, and an opening on the second side that is in close contact with the periphery of the ventilation hole.

[0012] Furthermore, the trigger switch is characterized in that the sum of the volume of the space within the outer tubular member and the volume of the space excluding the space occupied by the inner tubular member from the frame is substantially constant regardless of the position of the shaft member.

[0013] Furthermore, the trigger switch is characterized in that the interior of the external tubular member and the interior of the frame are communicated with each other via the insertion hole so that gas can pass therethrough.

[0014] In addition, the trigger switch is characterized in that it includes: a movable contact, which is accommodated in the frame and installed on the second side of the shaft member; and a fixed contact, which is installed in the frame and is connected to / separated from the movable contact, and the movable contact and the fixed contact are arranged in an area where gas can pass.

[0015] Furthermore, the trigger switch is characterized by including a biasing member that biases the shaft member toward the first side, and the outer tubular member or the inner tubular member covers the biasing member.

[0016] Furthermore, the trigger switch is characterized in that the first side of the outer tubular member is open and is fixed in close contact with the periphery near the end portion on the first side of the shaft member.

[0017] [Effects of the Invention]

[0018] The trigger switch disclosed in the present application exhibits excellent effects such as being able to improve the airtightness of the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic perspective view showing an example of the appearance of the electric device disclosed in the present application.

[0020] Figure 2This is a schematic perspective view showing an example of the appearance of the trigger switch disclosed in the present application.

[0021] Figure 3 This is a schematic perspective view showing an example of the appearance of the trigger switch disclosed in the present application.

[0022] Figure 4 This is an exploded perspective view showing an example of the internal structure of the trigger switch disclosed in the present application.

[0023] Figure 5 This is an exploded perspective view showing an example of the internal structure of the trigger switch disclosed in the present application.

[0024] Figure 6 This is a side sectional view showing an example of the internal structure of the trigger switch disclosed in the present application.

[0025] Figure 7 This is a side sectional view showing an example of the internal structure of the trigger switch disclosed in the present application.

[0026] Figure 8 This is a side sectional view showing an example of the internal structure of the trigger switch disclosed in the present application.

[0027] Explanation of Figure Numbers

[0028] PT: Electric device

[0029] TS: Trigger Switch

[0030] 1: Trigger cover

[0031] 2: Shaft component

[0032] 20: Moving Wall

[0033] 21: Movable contact

[0034] 22: Separation Wall

[0035] 3: Frame

[0036] 30: Front wall (first wall)

[0037] 31: Through hole

[0038] 32: Opening

[0039] 33: rear wall (second wall)

[0040] 33a: vent

[0041] 4: Force-applying component

[0042] 5: External tubular member

[0043] 6: Metal buckle

[0044] 7: Internal tubular member

[0045] 8: Substrate

[0046] 80: Fixed contact DETAILED DESCRIPTION

[0047] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0048] Application Examples

[0049] The trigger switch disclosed in this application is applicable to various electric devices, including electric tools such as electric drills, electric screwdrivers, electric wrenches, and electric grinders, which include a motor as a driving unit. The following describes an electric device PT and a trigger switch TS mounted on the electric device PT, as illustrated in the accompanying drawings.

[0050] <Electric PT Device>

[0051] Figure 1 This is a schematic perspective view showing an example of the appearance of the electric device PT disclosed in this application. The electric device PT disclosed in this application can be applied to power tools such as electric drills, electric screwdrivers, electric wrenches, and electric grinders. Furthermore, it can be applied to various devices including trigger switches TS, such as water guns, paint guns, and model guns. Figure 1 The illustrated electric device PT has a handle attached to a roughly cylindrical main body that houses a drive unit (not shown), such as an electric motor. A trigger switch TS, used to operate the electric device PT, is attached to the handle. In the following description, as shown in the figure, the roughly cylindrical main body is oriented upward, and the handle is oriented downward. Furthermore, the direction in which a rotary tool, such as a drill bit, is attached is oriented forward, and the direction in which the trigger switch TS is pressed in is oriented backward. In other words, in the trigger switch TS assembled into the electric device PT, the direction from front to rear is the direction in which it is pressed in. These directions are for convenience of description and do not limit the directions in which the electric device PT and trigger switch TS are used.

[0052] <Trigger Switch TS>

[0053] Next, the trigger switch TS included in the electric device PT will be described. Figure 1In the illustrated electric device PT, the trigger cover 1 of the trigger switch TS that receives the operator's push operation is exposed to the outside of the electric device PT. The trigger switch TS is a device that receives the operator's push operation and is assembled to the electric device PT in an operable state with the trigger cover 1 exposed. The trigger cover 1 of the trigger switch TS never receives the operator's push operation. Figure 1 The release position in the state of the push-in operation shown receives the push-in operation and moves in the push-in direction (from the front [first side] to the rear [second side]).

[0054] The internal structure of the trigger switch TS will be described. Figure 2 and Figure 3 This is a schematic perspective view showing an example of the appearance of the trigger switch TS disclosed in the present application. Figure 4 and Figure 5 This is an exploded perspective view showing an example of the internal structure of the trigger switch TS disclosed in the present application. Figure 6 This is a side sectional view showing an example of the internal structure of the trigger switch TS disclosed in the present application. Figures 2 to 6 The trigger cover 1 is shown in a state where the trigger switch TS is removed for easier viewing of the structure. The trigger cover 1 can be attached to and detached from the trigger switch TS.

[0055] Trigger switch TS except Figure 1 In addition to the trigger cover 1 shown, the trigger cover also includes various components such as a shaft member 2, a frame 3, a force applying member 4, an outer tubular member 5, a metal buckle 6, an inner tubular member 7, and a base plate 8.

[0056] The shaft member 2 is a plunger that transmits the operation received by the trigger cover 1. The trigger cover 1 is attached to the front side (first side) of the shaft member 2, and the rear side (second side) is housed within a roughly rectangular parallelepiped frame 3. The rear side of the shaft member 2 is housed so as to be movable and inserted through an insertion hole 31 formed in a front wall portion 30 (first wall portion) on the front surface of the frame 3. The outer diameter of the movable shaft member 2 is slightly smaller than the inner diameter of the insertion hole 31. A movable wall 20 is formed at the rear end of the shaft member 2 within the frame 3. The movable wall 20 is an inner wall extending in the thickness direction in the front-to-back direction, and is formed into a hollow rectangular parallelepiped with open rear and bottom surfaces. A pair of movable contacts 21 are mounted on the upper surface of the movable wall 20 in a horizontally aligned manner. A partition wall 22 is formed between the pair of movable contacts 21 and on the outside of the movable contacts 21. The interior of the frame 3 is a roughly rectangular parallelepiped space, and the outer dimensions of the movable wall 20, including the partition wall 22, are slightly smaller than the inner diameter of the frame 3. Therefore, as the shaft member 2 moves forward and backward, the movable wall 20, formed at the rear end of the shaft member 2, moves forward and backward within the frame 3. On the upper surface of the movable wall 20, the area demarcated by the partition wall 22 serves as the area where the movable contact 21 and the fixed contact 80 come into contact and separate. This area forms a gap with the inner top surface of the frame 3 through the partition wall 22. Therefore, the area where the movable contact 21 and the fixed contact 80 are located, as well as the gap between the movable wall 20 and the inner surface of the frame 3, allows gas to pass through.

[0057] A biasing member 4, such as a compression coil spring, is wound around the front portion of the shaft member 2, which is exposed outside the frame 3. This biasing member 4 biases the shaft member 2 forward (toward the first side). The biasing member 4 is secured to the shaft member 2 at its front end by a metal buckle 6, such as an E-ring, while its rear end is secured in contact with the front wall 30 of the front surface of the frame 3. Furthermore, the front portion of the shaft member 2, which is exposed outside the frame 3, and the biasing member 4, which is wound around the front portion of the shaft member 2, are covered by an outer tubular member 5, which is formed into a generally tubular shape from a flexible material such as resin. The outer tubular member 5 has a corrugated shape that expands and contracts in its longitudinal direction. The opening at the front end (first side) is secured in a manner that is tightly and closely attached to the periphery of the shaft member 2 near its front end. In other words, the front end of the outer tubular member 5 is sealed at the front end of the shaft member 2. The rear end (second side) of the outer tubular member 5 is secured in close contact with the periphery of the insertion hole 31 in the front surface of the frame 3. Therefore, the outer tubular member 5 is sealed from the insertion hole 31 on the front surface of the frame 3 to the vicinity of the front end of the shaft member 2. In addition, as mentioned above, the outer diameter of the shaft member 2 is formed to be slightly smaller than the inner diameter of the insertion hole 31. Therefore, the interior of the tube of the outer tubular member 5 is connected to the inside of the frame 3 in a manner that gas can enter and exit through the insertion hole 31. In addition, the so-called state in which the rear end of the outer tubular member 5 is in close contact with the periphery of the insertion hole 31 refers to the state in which the interior of the outer tubular member 5 and the interior of the frame 3 are sealed in a connected state via the opening at the rear end of the outer tubular member 5 and the insertion hole 31. Therefore, the trigger switch TS disclosed in the present application can be realized in various forms, such as making the outer tubular member 5 embedded in the insertion hole 31, in addition to making the opening of the outer tubular member 5 externally embedded in the protrusion around the insertion hole 31 and fixing it as illustrated.

[0058] The frame 3 is formed into a hollow, roughly rectangular parallelepiped shape, housing various components such as the rear side of the shaft member 2, the internal tubular member 7, and the base plate 8. A roughly circular insertion hole 31 is formed in the front wall portion 30 of the front surface of the frame 3, through which the shaft member 2 is inserted. The rear surface of the frame 3 forms an opening 32, which is closed by a rear wall portion 33 (second wall portion). The rear wall portion 33 is formed into a roughly rectangular plate-like shape that matches the shape of the opening 32, and is inserted into the opening 32 to seal it. A roughly circular ventilation hole 33a is formed in the approximate center of the rear wall portion 33.

[0059] The internal tubular member 7 housed within the frame 3 is formed into a roughly tubular shape from a flexible material such as resin. The internal tubular member 7 is corrugated and expands and contracts along its length. Its front end (first side) is sealed and fixed in contact with the rear surface of the movable wall 20 of the shaft member 2. The rear end (second side) of the internal tubular member 7 is fixed in close contact with the periphery of the vent hole 33a in the rear wall portion 33 of the frame 3. Therefore, the front end of the internal tubular member 7 is sealed, while the rear end is open to the outside of the frame 3. Therefore, while air from outside the frame 3 can flow in and out of the tube of the internal tubular member 7, air from within the frame 3 cannot. Furthermore, the state in which the rear end of the internal tubular member 7 is in close contact with the periphery of the vent hole 33a means that the inside of the internal tubular member 7 is connected to the outside of the frame 3 via the opening at the rear end of the internal tubular member 7 and the vent hole 33a, and that the internal tubular member 7 is sealed in such a way that air cannot flow in or out of the frame 3. Therefore, the trigger switch TS disclosed in the present application can be implemented in various forms such as fixing the inner tubular member 7 around the vent hole 33a, in addition to fitting the rear end of the inner tubular member 7 inside the vent hole 33a and fixing it as shown.

[0060] The base plate 8 is plate-shaped and mounted on the inner top surface of the frame 3. A pair of fixed contacts 80 are mounted on the lower surface of the base plate 8. The fixed contacts 80 form an electrical circuit with the movable contact 21 mounted on the movable wall 20 of the shaft member 2. The movable contact 21 moves as the shaft member 2 moves forward and backward. This movement brings the movable contact 21 into contact with and out of contact with the fixed contact 80, thereby opening and closing the electrical circuit.

[0061] Next, the operation of the trigger switch TS will be described. Figure 7 and Figure 8 This is a side sectional view showing an example of the internal structure of the trigger switch TS disclosed in the present application. Figure 7 The trigger switch TS is in a released state where it has not received a push operation. Figure 8 The trigger switch TS receives the push operation. Figure 7 The release state shown is transferred to Figure 8 In addition, when the operator releases the pressing operation, the shaft member 2 is urged by the urging member 4, and the trigger switch TS is released. Figure 8 The pressed state shown is transferred to Figure 7 Release state shown.

[0062] By transitioning from the released state to the pressed-in state, the shaft member 2 moves in the pressing direction. As the shaft member 2 moves, the outer tubular member 5 and the inner tubular member 7 shrink axially, reducing the volume of each tube. As the volume of the outer tubular member 5 decreases, the gas inside the tube flows out into the frame 3, maintaining the pressure inside the tube at a roughly constant level. By reducing the volume of the inner tubular member 7, the gas inside the tube flows out, reducing the space occupied by the inner tubular member 7 within the frame 3. Gas flows into the outer tubular member 5 within the frame 3, reducing the space occupied by the inner tubular member 7, thereby maintaining the pressure inside the frame 3 at a roughly constant level. Furthermore, within the frame 3, as the shaft member 2 moves, the rear end movable wall 20 moves in the pressing direction. However, due to the gap between the movable wall 20 and the inner surface of the frame 3, such as the area where the movable contact 21 and the fixed contact 80 are located, gas can pass through. Therefore, within the frame 3, the pressures before and after the movable wall 20 are roughly equal.

[0063] As described above, in the trigger switch TS disclosed in the present application, the sum of the volume of the space within the outer tubular member 5 (A in the figure) and the volume of the space (B in the figure) excluding the space occupied by the inner tubular member 7 from the frame 3 is substantially constant, regardless of the position of the shaft member 2. In other words, the pressure within the frame 3 is substantially constant. Furthermore, in the trigger switch TS disclosed in the present application, the volume of the space within the outer tubular member 5 and the volume of the space within the inner tubular member 7 (C in the figure) are substantially equal, regardless of the position of the shaft member 2.

[0064] As described above, the trigger switch TS disclosed herein maintains a substantially constant pressure in the space within the housing 3 where the movable contact 21 and the fixed contact 80 are located (excluding the space occupied by the internal tubular member 7 within the housing 3), even when the trigger moves due to a pressing operation. Consequently, the trigger switch TS disclosed herein suppresses the occurrence of a breathing effect, which causes pressure fluctuations within the housing 3, particularly within the area containing the movable contact 21 and the fixed contact 80. Consequently, the trigger switch TS disclosed herein maintains excellent airtightness, including waterproofing and dustproofing.

[0065] The present invention is not limited to the embodiments described above and can be implemented in various other forms. Therefore, the embodiments described are merely illustrative in all respects and cannot be interpreted in a restrictive manner. The scope of the present invention is indicated by the claims and is not restricted by the main text of the specification. Furthermore, all variations or modifications falling within the scope of the equivalents of the claims are within the scope of the present invention.

[0066] For example, the trigger switch of the embodiment shows a form in which the opening on the first side of the external tubular member is in close contact and sealed near the end of the first side of the shaft member, but the present invention is not limited to this and can be expanded to various forms such as using a trigger cover to seal the opening on the first side.

[0067] For example, the trigger switch of the above embodiment shows a configuration in which gas enters and exits through an insertion hole through which the shaft member is inserted, but the present invention is not limited thereto and can be developed into various configurations such as having holes for air to enter and exit in addition to the insertion hole.

[0068] In addition, for example, the trigger switch of the embodiment shows a form in which the urging member is arranged outside the frame and covered with an external tubular member, but the present invention is not limited to this and can be expanded to various forms such as a form in which the urging member is arranged inside the frame and covered with an internal tubular member.

[0069] That is, the trigger switch disclosed in the present application also includes the above-described embodiment and can be developed into various forms described below.

[0070] (Note 1)

[0071] A trigger switch includes: a shaft member, a trigger cover that is moved from a first side to a second side by a pressing operation and is mounted on the first side; and a frame that movably accommodates the second side of the shaft member. The trigger switch includes:

[0072] a flexible outer tubular member covering the shaft member on the exterior of the frame; and

[0073] a flexible inner tubular member received within the frame and mounted on the second side of the shaft member;

[0074] The frame is

[0075] An insertion hole for inserting the shaft member is formed in the first wall portion of the first side.

[0076] A vent hole is formed on the second wall portion of the second side.

[0077] The outer tubular member is

[0078] The end portion of the first side is sealed on the first side of the shaft member,

[0079] The opening on the second side is in close contact with the periphery of the insertion hole.

[0080] The inner tubular member is

[0081] The end of the first side is sealed,

[0082] The opening of the second side is in close contact with the periphery of the vent hole.

[0083] (Note 2)

[0084] The trigger switch according to Supplementary Note 1, wherein:

[0085] The sum of the volume of the space within the outer tubular member and the volume of the space obtained by excluding the space occupied by the inner tubular member from the frame is substantially constant regardless of the position of the shaft member.

[0086] (Note 3)

[0087] The trigger switch according to Supplement 1 or Supplement 2, wherein:

[0088] The interior of the outer tubular member and the interior of the frame are communicated with each other via the insertion hole so that gas can pass therethrough.

[0089] (Note 4)

[0090] The trigger switch according to Supplementary Note 3, comprising:

[0091] a movable contact housed in the frame and mounted on the second side of the shaft member; and

[0092] The fixed contact is installed in the frame and is connected to / separated from the movable contact.

[0093] The movable contact and the fixed contact are arranged in a region where gas can pass.

[0094] (Note 5)

[0095] The trigger switch according to any one of Supplementary Notes 1 to 4, comprising a biasing member,

[0096] The urging member urges the shaft member toward a first side.

[0097] The outer tubular member or the inner tubular member covers the force applying member.

[0098] (Note 6)

[0099] The trigger switch according to any one of Supplementary Notes 1 to 5, wherein:

[0100] The first side of the outer tubular member is open, and

[0101] The shaft member is fixed in close contact with the periphery of the first-side end portion thereof.

Claims

1. A trigger switch comprising: The shaft member is mounted on the first side of a trigger cover that is moved from the first side to the second side by a press-in operation; and a frame for movably accommodating the second side of the shaft member, wherein the trigger switch is characterized by comprising: a flexible outer tubular member covering the shaft member on the exterior of the frame; and a flexible inner tubular member received within the frame and mounted on the second side of the shaft member; The frame is An insertion hole for inserting the shaft member is formed in the first wall portion of the first side. A vent hole is formed on the second wall portion of the second side. The outer tubular member is The end portion of the first side is sealed on the first side of the shaft member, The opening on the second side is in close contact with the periphery of the insertion hole. The inner tubular member is The end of the first side is sealed, The opening of the second side is in close contact with the periphery of the vent hole.

2. The trigger switch according to claim 1, wherein: The sum of the volume of the space within the outer tubular member and the volume of the space obtained by excluding the space occupied by the inner tubular member from the frame is substantially constant regardless of the position of the shaft member.

3. The trigger switch according to claim 1 or 2, characterized in that: The interior of the outer tubular member and the interior of the frame are communicated with each other via the insertion hole so that gas can pass therethrough.

4. The trigger switch according to claim 3, wherein: include: a movable contact received in the frame and mounted on the second side of the shaft member; as well as The fixed contact is installed in the frame and is connected to / separated from the movable contact. The movable contact and the fixed contact are arranged in a region where gas can pass.

5. The trigger switch according to claim 1 or 2, characterized in that: Including force-applying components, The urging member urges the shaft member toward a first side. The outer tubular member or the inner tubular member covers the force applying member.

6. The trigger switch according to claim 1 or 2, characterized in that: The first side of the outer tubular member is open, and The shaft member is fixed in close contact with the periphery of the first-side end portion thereof.

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