This application claims benefit of priority to Japanese Patent Application No. 2016-173992 filed on Sep. 6, 2016, which is hereby incorporated by reference in its entirety.
The present disclosure relates to a pressing input device that operates an operational body by swinging a drive arm to change the state of an electrically variable part such as a switch.
Japanese Unexamined Patent Application Publication No. 2006-92996 describes an arrangement related to a pressing input device (lever driven electrical component). This pressing input device includes, in a case, an operational body that can advance and retreat, a sliding member that is driven by being pushed by the operational body, and a detecting member to which an electric signal is output due to the operation of a sliding member. A drive lever is swingably supported by the case. When an external force is applied to the drive lever and it swings, the operational body is pressed into the interior of the case by the drive lever.
The drive lever of the pressing input device described in Japanese Unexamined Patent Application Publication No. 2006-92996 has a restricting part for preventing an inclination. The driving lever and inclination prevention restricting part abut the contact part of the operational body at an angle. This restricts the inclined operation of the operational body when the operational body is pushed by the drive lever.
The pressing input device described in Japanese Unexamined Patent Application Publication No. 2006-92996 is structured so that when the drive lever is rotated, the operational body is pressed, so an operation force is more easily transmitted to the operational body when compared with a structure in which the operational body is directly pressed. A position at which the operational body is pressed to switch the ON state of a switch mechanism, which is the detecting means provided in the case, to the OFF state or to switch the OFF state to the ON state can be set with respect to the swing angle of the drive lever. This enables a timing to switch the switch mechanism to be easily designed.
However, the structure described in Japanese Unexamined Patent Application Publication No. 2006-92996 lacks a return mechanism that returns the drive lever to its initial orientation as a single component. This is problematic in that the drive lever causes a rattle and rattle noise is likely to occur. Another problem with the structure is that the elastic force of a return spring that protrudes the operational body from the case is used to rotate the drive lever to return it toward its initial orientation, so if a load exerted on the rotational fulcrum of the drive lever is increased, a load used to protrude the operational body from the case becomes excessive, lowering reliability in the operation of the operational body.
A possible solution to the above problems is a structure in which a leaf spring is provided so that the base of the leaf spring is fixed to the case, instead of the drive lever. The leaf spring is warped to press the operational body. In this structure, when the operation force exerted on the leaf string is removed, the leaf spring can return to its initial orientation due to its elastic force.
In this structure, however, the longer a distance by which the leaf string is pressed is, the more the leaf spring is warped and the larger elastic reaction force becomes. This increases the operation load. To reduce the operation load, it is necessary to elongate the leaf string to lower its spring constant. To use the leaf spring in an elastic region for a long time, it is also necessary to elongate the leaf spring to lower internal stress generated when the leaf string is warped. As a result, it becomes difficult to downsize the pressing input device.
A pressing input device that includes: a fixed part; an operational body supported by the fixed part so as to be capable of advancing and retreating; an electrically variable part, the state of the electrically variable part being changed by the operation of the operational body; and a driving arm that swings around a linkage part linked to the fixed part, the linkage part acting as a fulcrum, in a direction in which the drive arm presses the operational body; the pressing input device according to the present invention is characterized in that a spring piece is attached to the drive arm, the bottom end of the spring piece is positioned between the linkage part and a pressing part at which the drive arm presses the operational body, the spring piece is in contact with the fixing part, and when the drive arm swings in the direction in which the drive arm presses the operational body, the spring piece is deformed so as to warp.
As illustrated in
The base 2 is made of a synthetic resin. A first fixed contact 4a and a second fixed contact 4b are buried in the base 2. The first fixed contact 4a and second fixed contact 4b are made of a conductive metal plate. The first fixed contact 4a is positioned on the X2 side, and the second fixed contact 4b is positioned on the X1 side. The first fixed contact 4a is exposed from a resin protrusion 2a formed on the base 2 and extends in the Z1 direction. Similarly, the second fixed contact 4b is exposed from a resin protrusion 2b formed on the base 2 and extends in the Z1 direction. However, an insulative sliding part 2c is formed on the top of the second fixed contact 4b on the Z1 side so as to be continued to the top; the insulative sliding part 2c is integrally formed from the synthetic resin forming the base 2.
An operational body 5 is accommodated in the case 3. The operational body 5 integrally has an operational protrusion 5a extending in the Z1 direction and two sliding parts 5b extending in the Z1-Z2 direction, one of which is formed on the X1 side and the other of which is formed on the X2 side. An operation hole 3a is formed in the upper surface 3b of the case 3 in the Z1 direction. The operational protrusion 5a of the operational body 5 is inserted into the operation hole 3a, and the sliding parts 5b are guided in the Z1-Z2 direction by a guiding part formed in the case 3 so that the operational body 5 is supported in the case 3 so as to be movable in the Z1-Z2 direction.
A movable contact 6 is fixed to the bottom part 5c of the operational body 5. The movable contact 6 is formed from a conductive metallic leaf spring. The movable contact 6 has a first holding part 6a and a second holding part 6b. The first holding part 6a holds the first fixed contact 4a, and the second holding part 6b holds the insulative sliding part 2c and second fixed contact 4b.
A return spring 7, which is a compressing spring, is provided between the base 2 and the movable contact 6. The return spring 7 constantly urges the operational body 5 in the Z1 direction.
In this description, the first fixed contact 4a, second fixed contact 4b, insulative sliding part 2c, and movable contact 6 constitute an electrically variable part. This electrically variable part is a switch mechanism that is switched between an OFF state, in which the first fixed contact 4a and second fixed contact 4b are insulated from each other, and an ON state, in which the first fixed contact 4a and second fixed contact 4b are electrically connected, according to the position of the movable contact 6, which moves together with the operational body 5. The electrically variable part may be any device if its electric state and the state of an electronic signal can be switched or can change. An example of the electrically variable part is a multi-contact switch mechanism in which a plurality of contacts can make a switchover between an insulated state and an electrically connected state, according to the movement of the operational body 5. Another example is a variable resistor the resistance of which changes according to the movement of the operational body 5.
A waterproof cap 8 is attached to the top of the case 3 in the Z1 direction. As illustrated in
A drive arm 10 is attached to the case 3. The drive arm 10 is formed from an elastically deformable metallic plate. The drive arm 10 integrally has a pair of support pieces 11 at the base with a space left between them in the Y1-Y2 direction. The support pieces 11 are bent toward the X2 direction. A linkage hole 11a is made in each support piece 11. A pair of linkage protrusions 3c are integrally formed on the X1 side of the case 3, one of which protrudes in the Y1 direction, and the other of which is protrudes in the Y2 direction. Each linkage hole 11a is swingably (rotatably) supported by the corresponding linkage protrusion 3c. The linkage hole 11a and linkage protrusion 3c form a linkage part (see
Alternatively, the pair of support pieces 11 may be disposed so as to leave the minimum space between each support piece 11 and the case 3.
The drive arm 10 has a stopper piece 13 below the support pieces 11 (on the Z2 side), which is formed so as to be bent. As illustrated in
The drive arm 10 has an operational piece 14, which extends from the support pieces 11 at angle toward the Z1 direction and X2 direction. As illustrated in
The operational piece 14 of the drive arm 10 has a spring piece 16 between the pair of support pieces 11 and the pressing part 15. The spring piece 16 is preferably formed integrally as part of the drive arm 10 by cutting part of the metallic plate, from which the drive arm 10 is formed, and raising the cut portion. The spring piece 16 is bent from its bend bottom end 16a downwardly at an angle. The spring piece 16 is formed to such a dimension that the spring piece 16 is elastically warped. In an embodiment in which the drive arm 10 and a spring piece are integrally formed, the bend bottom end 16a is the bottom end of the spring piece.
As illustrated in
Next, the operation of the pressing input device 1 will be described.
In the initial state illustrated in
In an apparatus in which the pressing input device 1 is installed, when a to-be-detected part, such as a cam or slider, which is moved by a mechanism, moves and abuts the surface of the operational piece 14 of the drive arm 10 on the Z1 side, an operational force F is exerted on the drive arm 10 so as to swing it toward the case 3.
The operational force F causes the drive arm 10 to swing clockwise with the linkage part 12 acting as a swinging fulcrum. In the process in which the drive arm 10 is swung clockwise, the operational piece 14 abuts the operational protrusion 5a at the pressing part 15, as illustrated in
When the operational body 5 is pressed in the interior of the case 3 in the Z2 direction, the second holding part 6b moves from the position at which it has been holding the insulative sliding part 2c to the position at which the second holding part 6b holds the second fixed contact 4b, while the first holding part 6a of the movable contact 6, which moves together with the operational body 5, holds the first fixed contact 4a. Then, the first fixed contact 4a and second fixed contact 4b are electrically interconnected through the movable contact 6, switching the state of the electrically variable part to ON.
While the drive arm 10 is swinging clockwise with the linkage part 12 acting as a swinging fulcrum, the spring piece 16 in contact with the angular part 3e of the case 3 at the contact part 17 is deformed so as to warp with the bend bottom end 16a acting as a fulcrum. Due to the elastic return force generated by the warp of the spring piece 16, a rotational return force f in the counterclockwise direction continues to act on the drive arm 10. Therefore, when the operational force F is removed, the drive arm 10 swings counterclockwise due to the rotational return force f and returns to the initial orientation as illustrated in
With the pressing input device 1 in the first embodiment, the rotational return force f generated by the warp of the spring piece 16 does not become excessive even when the drive arm 10 swings clockwise and the drive arm 10 does not give an excessive operational reaction force even when the drive arm 10 swings as illustrated in
How the spring piece 16 is warped will be described below in details.
As illustrated in
The bend bottom end 16a of the spring piece 16 is positioned between the pressing part 15, which presses the operational protrusion 5a, and the linkage part 12, which acts as the swinging fulcrum. The contact part 17 between the spring piece 16 and the angular part 3e of the case 3 is preferably positioned closer to the linkage part 12 than the bend bottom end 16a is. That is, the contact part 17 is preferably positioned closer to the swinging fulcrum of the drive arm 10 than the bend bottom end 16a is. Therefore, when the drive arm 10 swings clockwise from the initial orientation “a” to the completely swung orientation “d”, the bend bottom end 16a rotates in a direction oriented so as to reduce the amount of warp of the spring piece 16.
In
As illustrated in
Therefore, when the drive arm 10 swings clockwise, the spring piece 16 preferably slides on the angular part 3e of the case 3 at the contact part 17. As a result, a length Ld from the bend bottom end 16a of the spring piece 16 to the contact part 17 in the completely swung orientation “d” illustrated in
While the drive arm 10 swings from the initial orientation “a” to the completely swung orientation “d”, the spring piece 16 causes a warp with an angle of β as illustrated in
In
An angle γ is formed between the orientation of the elastic reaction force fr perpendicularly exerted on the spring piece 16 at the contact part 17 and the tangent of the virtual circle C, the tangent passing the contact part 17. The angle γ is preferably increased as the drive arm 10 swings clockwise as illustrated in
As described above, when the position of the bend bottom end 16a and an angle at which the spring piece 16 of the drive arm 10 extends are set, it is possible to set the rotational return force f so that as the drive arm 10 swings clockwise, the rotational return force f is reduced. In addition, when the position of the bend bottom end 16a is changed and the angle at which the spring piece 16 of the drive arm 10 extends is changed to an arbitrary angle, it is possible to set the rotational return force f so that an amount by which the rotational return force f changes can be changed in response to a change in the swing angle of the drive arm 10.
With the pressing input device 1 in the first embodiment, when the drive arm 10 is swung from the initial orientation “a” to the completely swung orientation “d”, the elastic return force given from the return spring 7, which is a compression spring, to the operational body 5 is increased as illustrated in
With this pressing input device 101, a deformed part is formed at the top end of a spring piece 116 that is bent from the operational piece 14 of the drive arm 10 and extends. The deformed part abuts the upper surface 3b of the case 3, forming a contact part 117. When the drive arm 10 swings from the initial orientation “a” to the completely swung orientation “d”, the top end of the spring piece 116 preferably slides on the upper surface 3b of the case 3, shifting the position of the contact part 117 between the spring piece 116 and the upper surface 3b in the X1-X2 direction.
With this pressing input device 101 as well, the contact part 117 is preferably positioned closer to the linkage part 12 than the bend bottom end 116a of the spring piece 116 is, and the bend bottom end 116a moves on an arc path Φ that has a radius R and also has the center O at the linkage part 12. Therefore, when the drive arm 10 swings from the initial orientation “a” toward the completely swung orientation “d”, the warp angle of the spring piece 116 of the drive arm 10 is small, so the rotational return force f generated by the spring piece 116 can be reduced to a value lower than the initial rotational urging force f0 in the initial orientation “a”.
With the pressing input device 101 in the second embodiment as well, therefore, it is possible to reduce the rotational load of the drive arm 10.
Although the spring piece 16 in the first embodiment and the spring piece 116 in the second embodiment are formed integrally with the operational piece 14 of the drive arm 10, the spring pieces 16 and 116 may be formed separately from the drive arm 10 and may be attached to the operational piece 14. In an embodiment in which a spring piece is formed separately and is attached to a drive arm, a part at which the spring piece is combined with, connected to, or fixed to the drive arm 10 is the base of the spring piece.
Number | Date | Country | Kind |
---|---|---|---|
2016-173992 | Sep 2016 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
2468673 | Kaminky | Apr 1949 | A |
2817725 | Rochfort | Dec 1957 | A |
3484572 | Froyd | Dec 1969 | A |
3648004 | Williams, III | Mar 1972 | A |
4295017 | Kashima | Oct 1981 | A |
Number | Date | Country |
---|---|---|
102014217184 | Mar 2016 | DE |
1 734 548 | Dec 2006 | EP |
52-80484 | Jul 1977 | JP |
2006-092996 | Apr 2016 | JP |
Number | Date | Country | |
---|---|---|---|
20180068814 A1 | Mar 2018 | US |