Patent Description:
<CIT> relates to an input device including a metal member, and discloses a technique of providing an intermediate portion embedded in a resin casing with recessed and projecting portions across the intermediate portion, thereby enhancing adhesiveness between the resin casing and the intermediate portion and suppressing entry of water into a housing portion of the resin casing from a gap between the metal member and the resin casing.

The technique of <CIT> may cause entry of flux into a contact portion of the metal member through travelling of the flux in the intermediate portion of the metal member upon soldering for a terminal of the metal member. <CIT> discloses another example of flux suppressing arrangement.

A switch according to one embodiment includes the features of claim <NUM>.

According to one embodiment, it is possible to suppress entry of flux into a contact portion of a metal terminal upon soldering for the metal terminal.

Hereinafter, referring to the drawings, one embodiment will be described. Note in the following description that, for the sake of convenience, a Z-axis direction in the drawings is referred to as an upward-and-downward direction, a Y-axis direction in the drawings is referred to as a leftward-and-rightward direction, and an X-axis direction in the drawings is referred to as a forward-and-backward direction. However, a positive Z-axis direction is an upward direction, a positive Y-axis direction is a rightward direction, and a positive X-axis direction is a forward direction.

<FIG> is a perspective view of the outer appearance of the switch <NUM> according to one embodiment. As illustrated in <FIG>, the switch <NUM> is formed, as a whole, in a rectangular parallelepiped shape that is thin in the upward-and-downward direction (Z-axis direction). As illustrated in <FIG>, in the switch <NUM>, a top surface 160A and a housing portion 160B of the housing <NUM> are covered with an insulator <NUM> that is transparent. At a central portion of the insulator <NUM>, a bump portion <NUM> is formed in a shape that is projecting upward (positive Z-axis direction). A press body <NUM> is adhered to a rear surface (negative Z-axis side) of the bump portion <NUM>. Thereby, the switch <NUM> allows for a downward (negative Z-axis direction) pressing operation via the press body <NUM>.

The switch <NUM> is in an OFF state when the pressing operation is not applied to the press body. The switch <NUM> switches to be in an ON state when the downward (negative Z-axis direction) pressing operation is applied to the press body <NUM>.

<FIG> is an exploded perspective view of the switch <NUM> according to one embodiment. <FIG> is a cross-sectional perspective view of the switch <NUM> according to one embodiment, taken along the YZ plane. As illustrated in <FIG> and <FIG>, the switch <NUM> includes the housing <NUM>, a metal contact <NUM>, the press body <NUM>, and the insulator <NUM> in order from the downward side (negative Z-axis side) in the drawings.

The housing <NUM> is a member in the form of a container, and the member is formed in a rectangular parallelepiped shape that is thin in the upward-and-downward direction (Z-axis direction). In a plan view from above, the housing <NUM> has a rectangular shape in which the leftward-and-rightward direction (Y-axis direction) is a longitudinal direction and the forward-and-backward direction (X-axis direction) is a transverse direction. The housing <NUM> has a housing portion 160B formed in a shape that is recessed downward from the top surface 160A. In the housing portion 160B, the metal contact <NUM> is housed. For example, the housing <NUM> uses a relatively hard insulating material (e.g., a hard resin) and is integrally formed with the central fixation contact member <NUM> and the peripheral fixation contact member <NUM> through insert molding.

A bottom portion 160C of the housing portion 160B of the housing <NUM> includes a central portion 160Ca and a peripheral portion 160Cb.

The central portion 160Ca is formed at the center of the bottom portion 160C. The central portion 160Ca is provided with a central fixation contact <NUM> included in the central fixation contact member <NUM>.

The peripheral portion 160Cb is formed at an outer side of the central portion 160Ca so as to surround the central portion 160Ca. The peripheral portion 160Cb has a higher height position than the central portion 160Ca. The peripheral portion 160Cb is provided with peripheral fixation contacts <NUM> included in the peripheral fixation contact member <NUM>. The metal contact <NUM> is placed in the peripheral portion 160Cb.

The central fixation contact member <NUM> and the peripheral fixation contact member <NUM> are members that are formed of metal and formed in a generally flat plate. The central fixation contact member <NUM> and the peripheral fixation contact member <NUM> are integrally formed with the housing <NUM> through insert molding. For example, the central fixation contact member <NUM> and the peripheral fixation contact member <NUM> are formed by processing a metal plate with various processing methods (e.g., a pressing process, a bend process, or a laser process).

The central fixation contact member <NUM> is one example of "metal terminal". The central fixation contact member <NUM> includes the central fixation contact <NUM> at a left-hand (negative Y-axis side) end portion and an external connection terminal <NUM> at a right-hand (positive Y-axis side) end portion. The central fixation contact <NUM> is one example of "contact portion" and disposed in the central portion 160Ca of the bottom portion 160C of the housing <NUM>. The external connection terminal <NUM> is provided to project from the right-hand (positive Y-axis side) lateral surface of the housing <NUM> and is to be connected to the exterior. The other portions of the central fixation contact member <NUM> (portions other than the central fixation contact <NUM> and the external connection terminal <NUM>) are embedded in the housing <NUM>.

The peripheral fixation contact member <NUM> includes: at the right-hand (positive Y-axis side) end portion, a pair of peripheral fixation contacts <NUM> that are along the forward-and-backward direction (X-axis direction); and an external connection terminal <NUM> at the left-hand (negative Y-axis side) end portion. The pair of peripheral fixation contacts <NUM> are disposed in the peripheral portion 160Cb of the bottom portion 160C of the housing <NUM>. The external connection terminal <NUM> is provided to project from the left-hand (negative Y-axis side) lateral surface of the housing <NUM> and is to be connected to the exterior. The other portions of the peripheral fixation contact member <NUM> (portions other than the peripheral fixation contacts <NUM> and the external connection terminal <NUM>) are embedded in the housing <NUM>.

The metal contact <NUM> is a dome-shaped member that is projecting upward (positive Z-axis direction) and includes a top portion <NUM> at the central portion thereof. The metal contact <NUM> is formed using one or more thin metal plates. In the present embodiment, as one example, the metal contact <NUM> is formed of two thin metal plates that are overlaid on top of each other. The metal contact <NUM> is housed in the housing portion 160B of the housing <NUM>, and placed at the peripheral portion 160Cb of the bottom portion 160C of the housing portion 160B. Thereby, the metal contact <NUM> contacts the peripheral fixation contacts <NUM> provided at the peripheral portion 160Cb, and is electrically connected to the peripheral fixation contact member <NUM>. The metal contact <NUM> is what is called "reverse spring". In response to application of the pressing operation to the press body <NUM>, the top portion <NUM> is pressed downward via the press body <NUM>, and once a predetermined operation load has been exceeded, the top portion <NUM> rapidly elastically deforms into a recessed shape (reverse motion). Thereby, the metal contact <NUM> contacts the central fixation contact <NUM> at a rear portion of the top portion <NUM>, and further is electrically connected to the central fixation contact member <NUM>. The metal contact <NUM> returns to the original projecting shape by an elastic force upon release of the pressing force from the press body <NUM>.

Note that, in the present embodiment, the metal contact <NUM> is formed by partially cutting a circular dome-shaped metal plate in a plan view from above, and includes four leg portions <NUM> respectively projecting in four mutually different directions in the plan view from above. In the present embodiment, the four leg portions <NUM> of the metal contact <NUM> are placed in the peripheral portion 160Cb of the housing <NUM>, and two leg portions <NUM> thereof contact the peripheral fixation contacts <NUM>.

The press body <NUM> is a member that is disposed above the top portion <NUM> of the metal contact <NUM> and within a rear space of the bump portion <NUM> of the insulator <NUM>. The press body <NUM> is circular in a plan view from above and has a three-dimensional shape projecting upward from the top portion <NUM> of the metal contact <NUM>. The press body <NUM> is formed of a resin material such as polyethylene terephthalate (PET). The press body <NUM> has a curved top surface portion contouring the bump portion <NUM> of the insulator <NUM>. The press body <NUM> is adhered, on the top surface portion thereof, to a rear portion of the bump portion <NUM> of the insulator <NUM> by given adhesion means (e.g., laser welding). In the present embodiment, the press body <NUM> has such a three-dimensional shape that a hemispherical shape is collapsed in the upward-and-downward direction (Z-axis direction). However, this is by no means a limitation. The press body <NUM> may be, for example, a cylindrical shape or an ellipsoidal shape. Also, the press body <NUM> is not limited to the press body that is circular in a plan view from above.

The insulator <NUM> is a thin-sheet member disposed on the top surface 160A of the housing <NUM>. The insulator <NUM> is formed of a resin material such as PET. In a plan view from above, the insulator <NUM> has approximately the same shape as the top surface 160A of the housing <NUM>; i.e., an approximately rectangular shape in which the leftward-and-rightward direction (Y-axis direction) is a longitudinal direction and the forward-and-backward direction (X-axis direction) is a transverse direction. With the insulator <NUM> covering the top surface 160A of the housing <NUM>, the insulator <NUM> is adhered to the top surface 160A of the housing <NUM> by given adhesion means (e.g., laser welding). The insulator <NUM> closes an upper opening of the housing portion 160B of the housing <NUM>, and seals the housing portion 160B. At the central portion of the insulator <NUM>, the bump portion <NUM> formed in a shape projecting upward (positive Z-axis direction) is formed. As illustrated in <FIG>, the press body <NUM> is adhered to the rear portion of the bump portion <NUM>.

According to the switch <NUM> according to one embodiment, when the pressing operation is not applied to the press body <NUM>, the metal contact <NUM> contacts the peripheral fixation contacts <NUM> and does not contact the central fixation contact <NUM>. Therefore, the switch <NUM> according to one embodiment is in an OFF state when the pressing operation is not applied to the press body <NUM>.

According to the switch <NUM> according to one embodiment, when the pressing operation is applied to the press body <NUM>, the press body <NUM> pushes down the top portion <NUM> of the metal contact <NUM>, and elastically deforms the top portion <NUM> of the metal contact <NUM> so as to be in a recessed shape (reverse motion). Thereby, the rear portion of the top portion <NUM> contacts the central fixation contact <NUM>, and the metal contact <NUM> is electrically connected to the central fixation contact member <NUM>. As a result, the switch <NUM> switches to be in an ON state through conduction, via the central fixation contact member <NUM>, between: the central fixation contact member <NUM> and the central fixation contact <NUM>; and the peripheral fixation contact member <NUM> and the peripheral fixation contacts <NUM>.

Note that, according to the switch <NUM> according to one embodiment, when the pressing operation applied to the press body <NUM> has been stopped, the metal contact <NUM> returns to the original projecting shape by its own elastic force. As a result, the metal contact <NUM> ceases being contact with the central fixation contact <NUM>, and the switch <NUM> returns to be in an OFF state.

<FIG> is a perspective view of the outer appearance of the housing <NUM> included in the switch <NUM> according to one embodiment. <FIG> is a perspective view of the outer appearance of the central fixation contact member <NUM> and the peripheral fixation contact member <NUM> included in the switch <NUM> according to one embodiment. <FIG> is a partially enlarged perspective view of the central fixation contact member <NUM> included in the switch <NUM> according to one embodiment. <FIG> is a partially enlarged cross-sectional view of the housing <NUM> included in the switch <NUM> according to one embodiment.

As illustrated in <FIG> and <FIG>, the central fixation contact member <NUM> includes the central fixation contact <NUM> (one example of "contact portion") at the left-hand (negative Y-axis side) end portion and the external connection terminal <NUM> (one example of "external connection portion") at the right-hand (positive Y-axis side) end portion. The central fixation contact <NUM> is disposed in the central portion 160Ca of the bottom portion 160C of the housing <NUM>. The external connection terminal <NUM> is provided to project from the right-hand (positive Y-axis side) lateral surface of the housing <NUM>.

Also, as illustrated in <FIG>, the central fixation contact member <NUM> includes an embedded portion <NUM> between the central fixation contact <NUM> and the external connection terminal <NUM>, the embedded portion <NUM> being to be embedded in the housing <NUM>.

The embedded portion <NUM> is extended in the leftward-and-rightward direction (Y-axis direction) that is an extending direction and in the forward-and-backward direction (X-axis direction) that is a widthwise direction. As illustrated in <FIG>, the embedded portion <NUM> has a plurality of groove portions <NUM> extending in the widthwise direction (X-axis direction), the groove portions <NUM> being alternately formed in a front surface 173A and in a rear surface 173B.

Thereby, in the switch <NUM> according to one embodiment, when the housing <NUM> is insert-molded, the resin of the housing <NUM> enters the plurality of groove portions <NUM>, thereby forming a plurality of wall portions <NUM> in the plurality of groove portions <NUM> (see <FIG>).

According to the switch <NUM> according to one embodiment, therefore, when soldering is performed on the external connection terminal <NUM>, the plurality of wall portions <NUM> can prevent flux from spreading to (i.e., wetting) the central fixation contact <NUM> side (negative Y-axis side) from the external connection terminal <NUM> side (positive Y-axis side) in the front surface 173A and the rear surface 173B of the embedded portion <NUM>.

Also, according to the switch <NUM> according to one embodiment, the outflow path of flux is expanded by the presence of the plurality of groove portions <NUM> in the front surface 173A and the rear surface 173B of the embedded portion <NUM>. This also contributes to suppression of flux from spreading to (i.e., wetting) the central fixation contact <NUM> side (negative Y-axis side) from the external connection terminal <NUM> side (positive Y-axis side).

Moreover, according to the switch <NUM> according to one embodiment, the resin of the housing <NUM> enters the plurality of groove portions <NUM>, thereby increasing adhesiveness between the resin of the housing <NUM> and the front surface 173A and the rear surface 173B of the embedded portion <NUM> (i.e., approximately no gap occurs therebetween). This also contributes to suppression of flux from spreading to (i.e., wetting) the central fixation contact <NUM> side (negative Y-axis side) from the external connection terminal <NUM> side (positive Y-axis side).

According to the switch <NUM> according to one embodiment, therefore, when soldering is performed on the external connection terminal <NUM>, it is possible to suppress entry of flux into the central fixation contact <NUM>.

In particular, the switch <NUM> according to one embodiment has the plurality of groove portions <NUM> that are alternately formed in the front surface 173A and in the rear surface 173B. Therefore, as compared with a case where the groove portions <NUM> are formed at the same positions in the front surface 173A and the rear surface 173B of the embedded portion <NUM>, each of the groove portions can be formed deeper, and thus it is possible to increase the effect of suppressing entry of flux.

In particular, as illustrated in <FIG>, the embedded portion <NUM> includes a narrow-width portion <NUM> that is partially narrow in width, and the plurality of groove portions <NUM> are formed in the narrow-width portion <NUM>.

Thereby, according to the switch <NUM> according to one embodiment, the groove portions <NUM> can be made shorter in length than in a case where the groove portions <NUM> are formed in the other portions of the embedded portion <NUM>.

Note that, in the examples as illustrated in <FIG> and <FIG>, two groove portions <NUM> are formed in each of the front surface 173A and the rear surface 173B of the embedded portion <NUM>, but three or more groove portions <NUM> may be formed.

Also, in the examples as illustrated in <FIG> and <FIG>, the cross-sectional shape of the groove portion <NUM> is a rectangular shape that is open in a top portion thereof. However, the cross-sectional shape of the groove portion <NUM> may be another shape (e.g., a V shape, a U shape, or a trapezoidal shape that is open in a top portion thereof). Also, two groove portions <NUM> may be formed next to each other in each of the front surface 173A and the rear surface 173B of the embedded portion <NUM> such that the two groove portions <NUM> in the front surface 173A are formed at positions different from the two groove portions <NUM> in the rear surface 173B.

Also, the groove portions <NUM> are preferably formed through a laser process. Thereby, according to the switch <NUM> according to one embodiment, it is possible to form the groove portions <NUM> each having a cross-sectional shape becoming narrower in groove width as the groove portions become deeper and having an inner surface that is a coarse surface. This can increase the effect of entry of the resin of the housing <NUM> into the inner surfaces of the groove portions <NUM>.

Also, as illustrated in <FIG> and <FIG>, the groove portions <NUM> have such a length in the forward-and-backward (X-axis direction) that completely traverse the narrow-width portion <NUM> (i.e., a length the same as the width of the narrow-width portion <NUM>). Thereby, according to the switch <NUM> according to one embodiment, it is possible to increase the effect of the groove portions <NUM> on suppression of entry of flux.

Also, as illustrated in <FIG> and <FIG>, the groove portions <NUM> are preferably orthogonal to the extending direction of the narrow-width portion <NUM>. However, it is enough for the groove portions <NUM> to at least intersect the extending direction of the narrow-width portion <NUM>.

Also, the depth of the groove portions <NUM> is preferably equal to or less than <NUM>% of the plate thickness of the narrow-width portion <NUM>. For example, when the plate thickness of the narrow-width portion <NUM> is <NUM> micrometers, the depth of the groove portions <NUM> is preferably equal to or less than <NUM> micrometers. Thereby, the switch <NUM> according to one embodiment can suppress reduction in strength of the narrow-width portion <NUM>.

Also, when the groove portions <NUM> are formed through a laser process, projecting bump portions may be formed along the edge portions of the groove portions <NUM> in the front surface 173A and the rear surface 173B of the embedded portion <NUM>. In this case, according to the switch <NUM> according to one embodiment, it is possible to further increase the effect of suppressing entry of flux by virtue of the bump portions.

<FIG> is a partially enlarged cross-sectional view of one modified example of the configuration of the housing <NUM> included in the switch <NUM> according to one embodiment.

In the example as illustrated in <FIG>, two groove portions <NUM> are formed in each of the front surface 173A and the rear surface 173B in the narrow-width portion <NUM> of the embedded portion <NUM> of the central fixation contact member <NUM>. These groove portions <NUM> are formed alternately in the front surface 173A and in the rear surface 173B in the extending direction (Y-axis direction) of the central fixation contact member <NUM>.

Also, in the example as illustrated in <FIG>, the plurality of groove portions <NUM> are each formed through irradiation with laser light. Thereby, each of the plurality of groove portions <NUM> that have been formed has a cross-sectional shape becoming narrower in groove width as the groove portions become deeper and has an inner surface that is a coarse surface.

Therefore, the switch <NUM> according to one embodiment can increase the effect of entry of the resin of the housing <NUM> into the inner surfaces of the groove portions <NUM>.

Also, in the example as illustrated in <FIG>, since the groove portions <NUM> have been formed through laser irradiation, bump portions <NUM> are formed along both left-hand and right-hand edge portions of each of the groove portions <NUM> in the narrow-width portion <NUM> of the embedded portion <NUM> of the central fixation contact member <NUM>. The bump portions <NUM> are portions that are projecting in the upward-and-downward direction more than the front surface 173A and the rear surface 173B.

The switch <NUM> according to one embodiment includes the bump portions <NUM>, and can increase the effect of entry of the resin of the housing <NUM> and the effect of suppressing entry of flux.

Claim 1:
A switch (<NUM>), comprising:
a housing (<NUM>); and
a metal terminal (<NUM>) that is insert-molded into the housing (<NUM>),
the metal terminal (<NUM>) including
a contact portion (<NUM>) provided on a first side of the metal terminal,
an external connection portion (<NUM>) provided on a second side of the metal terminal (<NUM>), and
an embedded portion (<NUM>) provided between the contact portion (<NUM>) and the external connection portion (<NUM>) and embedded in the housing (<NUM>),
wherein the embedded portion (<NUM>) extends in a leftward-and-rightward direction that is an extending direction and in a forward-and-backward direction that is a widthwise direction,
wherein in the embedded portion (<NUM>),
groove portions (<NUM>) are formed in a front surface (173A) of the metal terminal and a rear surface (173B) of the metal terminal (<NUM>), the groove portions (<NUM>) in the front surface (173A) being formed at positions different from the groove portions (<NUM>) in the rear surface (173B),
the groove portions (<NUM>) extend in the widthwise direction that is a direction intersecting the extending direction of the embedded portion (<NUM>), and
the groove portions (<NUM>) are alternately formed in the front surface (173A) and in the rear surface (173B),
wherein the embedded portion (<NUM>) includes a narrow-width portion (<NUM>) that is partially narrow in width, and the groove portions (<NUM>) are formed in the narrow-width portion (<NUM>), and
wherein the groove portions (<NUM>) have a length in the forward-and-backward direction that is the same as the width of the narrow-width-portion (<NUM>).