Multi-directional input device

Abstract

A multi-directional input device 1 includes an upper housing 61, a first pivot member 62a held by the upper housing 61 so that the first pivot member 62a can be pivotally moved around a first axis direction, a second pivot member 62b held by the upper housing 61 so that the second pivot member 62b can be pivotally moved around a second axis direction, an operation shaft 63 for pivotally moving the first pivot member 62a and the second pivot member 62b according to a tilting operation applied from a user, and a holding mechanism 66 held by the upper housing 61 and elastically holding the operation shaft 63 in a neutral state. The holding mechanism 66 includes at least one upper leaf spring 9a and at least one lower leaf spring 9b which are fixedly held by the upper housing 61 so that the at least one upper leaf spring 9a and the at least one lower leaf spring 9b are spaced apart from each other in a height direction. The operation shaft 63 is connected to inner frames 92 of the at least one upper leaf spring 9a and the at least one lower leaf spring 9b.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priorities to Japanese Patent Application No. 2023-146209 filed on September 8, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-146210 filed on September 8, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-146211 filed on September 8, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-146212 filed on September 8, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-146213 filed on September 8, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-158273 filed on September 22, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-158274 filed on September 22, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-158275 filed on September 22, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", Japanese Patent Application No. 2023-158276 filed on September 22, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE", and Japanese Patent Application No. 2023-158277 filed on September 22, 2023, entitled "MULTI-DIRECTIONAL INPUT DEVICE". The contents of the above-listed applications are incorporated by reference for all purposes.TECHNICAL FIELD

[0002] The present invention generally relates to multi-directional input devices, in particular to a multi-directional input device which can provide input of direction information according to a tilting operation with respect to an operation shaft.BACKGROUND ART

[0003] Conventionally, a multi-directional input device for enabling a tilting operation with respect to an operation shaft has been known as a multi-directional input device used in an electronic device such as a game machine. This type of multi-directional input device is called a joystick or a stick controller. A user can perform the tilting operation for tilting the operation shaft from a neutral state toward an arbitrary direction to input direction information according to the tilting operation with respect to the operation shaft.

[0004] For example, patent document 1 discloses a multi-directional input device 500 shown in Fig. 1. The multi-directional input device 500 includes a housing 520 fixed on a bottom plate 510, a first pivot member 530 held by the housing 520 so that the first pivot member 530 can be pivotally moved around a first axis direction (the Y direction), a second pivot member 540 held by the housing 520 so that the second pivot member 540 can be pivotally moved around a second axis direction (the X direction) perpendicular to the first axis direction, an operation shaft 550 which is passed through a slit hole 531 of the first pivot member 530 and a slit hole 541 of the second pivot member 540 for pivotally moving the first pivot member 530 and the second pivot member 540 according to a tilting operation applied from a user and which can be displaced toward a lower side according to a pressing operation applied from the user, a movable member 560 provided on a lower end portion of the operation shaft 550 so that the movable member 560 can be moved along an axis direction of the operation shaft 550, a coil spring 570 provided between the operation shaft 550 and the movable member 560, a sensor 580 provided on the housing 520 for detecting pivot angles of the first pivot member 530 and the second pivot member 540, and a push switch 590 provided in a component attachment portion 510a protruding from one side wall of the bottom plate 510 toward the outer side.

[0005] When the user applies the tilting operation with respect to the operation shaft 550 toward an arbitrary direction, the first pivot member 530 and the second pivot member 540 are pivotally moved according to a tilting movement of the operation shaft 550. The pivot angles of the first pivot member 530 and the second pivot member 540 are respectively detected by the sensor 580 and thus the multi-directional input device 500 can provide the input of the direction information according to the tilting operation with respect to the operation shaft 550 from the user. Further, when the user applies the pressing operation with respect to the operation shaft 550, the second pivot member 540 engaged with the operation shaft 550 is displaced toward the lower side, and then the second pivot member 540 presses the push switch 590. Thus, the multi-directional input device 500 can provide the input of pressing information according to the pressing operation with respect to the operation shaft 550 from the user.

[0006] The movable member 560 includes a base portion 561 having a bottom surface curved in a dish shape, a cylindrical boss portion 562 which is formed on a central portion of the base portion 561 and into which the lower end portion of the operation shaft 550 is inserted, and an arcuate portion 563 protruding from an outer peripheral portion of the base portion 561 toward the outer side. In this multi-directional input device 500, when the user applies the tilting operation to the operation shaft 550, the movable member 560 slides on the bottom plate 510 in an initial state in which a tilt angle of the operation shaft 550 is small. When the tilt angle of the operation shaft 550 then exceeds a certain value, the movable member 560 is tilted while a lower surface of the arcuate portion 563 of the movable member 560 abuts against a protruding portion 510b formed on the bottom plate 510, and the movable member 560 is lifted along the axis direction of the operation shaft 550 against elastic force of the coil spring 570. After that, when the tilting operation with respect to the operation shaft 550 is released, the operation shaft 550 returns to a neutral state by elastic restoring force of the coil spring 570 and an action provided by a shape of the bottom surface of the base portion 561. As described above, the movable member 560 provides a function of elastically holding the operation shaft 550 in the upright neutral state.

[0007] Since the movable member 560 slides on the bottom plate 510 in the initial stage of the tilting operation with respect to the operation shaft 550, friction between the movable member 560 and the bottom plate 510 generates strong reaction force (reverse torque) against the tilting operation to the operation shaft 550 from the user. When the tilt angle of the operation shaft 550 then exceeds the certain value, the reaction force against the tilting operation to the operation shaft 550 from the user increases according to a lifting amount of the movable member 560 and the elastic force of the coil spring 570. Fig. 2 shows reaction force characteristics of the multi-directional input device 500 against the tilting operation to the operation shaft 550. As shown in Fig. 2, when the user applies the tilting operation to the operation shaft 550, the reaction force against the tilting operation of the user sharply increases according to an increase of the tilt angle of the operation shaft 550 in the initial stage in which the tilt angle of the operation shaft 550 is small. When the tilt angle of the operation shaft 550 then exceeds the certain value, an increase of the reaction force according to the increase of the tilt angle of the operation shaft 550 becomes extremely small.

[0008] The above-mentioned non-linear reaction force characteristics are particularly useful when the multi-directional input device 500 is used in a handheld controller of a game machine. When the user operates the handheld controller, the user applies the tilting operation to the multi-directional input device 500 with an arbitrary finger such as a thumb. In some cases, the user applies another operation (such as a pressing operation with respect to a button of the controller) with another finger to the controller independently of the tilting operation. When the other operation is applied to the controller, there is a risk that the user unintentionally applies a slight tilting operation to the multi-directional input device 500 in conjunction with the other operation of the other finger. If the multi-directional input device 500 sensitively responds to this slight tilting operation, the multi-directional input device 500 may perform an unintended behavior that the user does not desire. The above-mentioned non-linear reaction force characteristics can prevent the unintended behavior of the multi-directional input device 500 that the user does not desire.

[0009] However, in the multi-directional input device 500, since the movable member 560 slides on the bottom plate 510 when the operation shaft 550 performs the tilting movement, the friction is generated between the movable member 560 and the bottom plate 510. Further, since the movable member 560 moves along the axis direction of the operation shaft 550, another friction is also generated between the movable member 560 and the operation shaft 550. Therefore, there is a problem that the movable member 560 wears away and a product life of the multi-directional input device 500 is shortened if the tilting operation with respect to the operation shaft 550 is repeatedly performed.RELATED ART DOCUMENT PATENT DOCUMENT

[0010] Patent document 1: JP 2000-305650ASUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION

[0011] The present invention has been made in view of the above-mentioned problem. Accordingly, it is an object of the present invention to provide a multi-directional input device whose product life is long and which has desired non-linear reaction force characteristics against a tilting operation with respect to an operation shaft.MEANS FOR SOLVING THE PROBLEMS

[0012] The above object is achieved by the first to tenth aspects of the present inventions respectively defined by the following (1) to (10). (1) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, and wherein the operation shaft is connected with the inner frames of the at least one upper leaf spring and the at least one lower leaf spring in a state that the operation shaft is passed through the through-holes of the inner frames of the at least one upper leaf spring and the at least one lower leaf spring. (2) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, and wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring, wherein each of the plurality of spring portions of each of the at least one upper leaf spring and the at least one lower leaf spring includes: a first connecting portion connected to the outer frame, a second connecting portion connected to the inner frame, and an arm portion extending in an arcuate shape so as to connect between the first connecting portion and the second connecting portion, wherein the arm portion of each of the plurality of spring portions of the at least one upper leaf spring extends in the arcuate shape in one of a clockwise direction and a counterclockwise direction from the first connecting portion toward the second connecting portion in a planar view from the height direction, and wherein the arm portion of each of the plurality of spring portions of the at least one lower leaf spring extends in the arcuate shape in another one of the clockwise direction and the counterclockwise direction from the first connecting portion toward the second connecting portion in the planar view from the height direction. (3) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user and which can be displaced toward a lower side according to a pressing operation applied from the user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member; and a push switch located below the operation shaft and which should be pressed according to a downward displacement of the operation shaft, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, and wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring. (4) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft includes: an operation portion which should be operated by the user, and a spring connection portion linearly extending from a lower end portion of the operation portion toward a lower side, and wherein the inner frame of the at least one upper leaf spring and the inner frame of the at least one lower leaf spring are connected to the spring connection portion of the operation shaft in a state that the inner frame of the at least one upper leaf spring and the inner frame of the at least one lower leaf spring are spaced apart from each other in the height direction. (5) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes: at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, and a bush which is located between the at least one upper leaf spring and the at least one lower leaf spring, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the housing is located between the outer frame of the at least one upper leaf spring and the outer frame of the at least one lower leaf spring, wherein the bush is located between the inner frame of the at least one upper leaf spring and the inner frame of the at least one lower leaf spring, and wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring. (6) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring, and wherein the at least one upper leaf spring and the at least one lower leaf spring have planar shapes which are upside down relative to each other in a planar view from the height direction. (7) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring, wherein each of the at least one upper leaf spring and the at least one lower leaf spring is configured so that the outer frame and the inner frame are concentric to each other and the inner frame is located on an inner side of an inner peripheral surface of the outer frame, and wherein when a straight line is drawn toward the outer side from a center of the inner frame to an arbitrary point on the inner peripheral surface of the outer frame, each of the at least one upper leaf spring and the at least one lower leaf spring is configured so that at least one of the spring portions and two spaces which are respectively located on the outer side and the inner side of the at least one of the spring portions and in which the at least one of spring portions does not exist are located on the straight line. (8) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring, and wherein a rotational center of a tilting movement of the operation shaft performed according to the tilting operation applied from the user is located between the at least one upper leaf spring and the at least one lower leaf spring. (9) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the at least one upper leaf spring and the at least one lower leaf spring, wherein each of motion equations of a lateral-direction displacement of the operation shaft and a torsional-direction displacement of the operation shaft of the tilting movement of the operation shaft performed according to the tilting operation applied from the user can be expressed by a following equation (1), and F t = m d 2 x t d t 2 = − k sp x t wherein "F" is force applied to the operation shaft, "m" is a weight of the operation shaft, "x" is a displacement amount of the operation shaft, "t" is time, and "k sp " is a spring constant of the holding mechanism in the equation (1). (10) A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes a plurality of upper leaf springs and a plurality of lower leaf springs which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the plurality of upper leaf springs and the plurality of lower leaf springs includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, wherein the operation shaft is elastically held by the plurality of upper leaf springs and the plurality of lower leaf springs, each of the plurality of spring portions of each of the plurality of upper leaf springs and the plurality of lower leaf springs includes: a first connecting portion connected to the outer frame, a second connecting portion connected to the inner frame, and an arm portion extending in an arcuate shape so as to connect between the first connecting portion and the second connecting portion, wherein the first connecting portions, the second connecting portions, and the arm portions of the plurality of spring portions of the plurality of upper leaf springs overlap each other in a vertical direction, and wherein the first connecting portions, the second connecting portions, and the arm portions of the plurality of spring portions of the plurality of lower leaf springs overlap each other in the vertical direction. EFFECTS OF THE INVENTION

[0013] The multi-directional input device according to each aspect of the present invention is configured so that the operation shaft is elastically held in the neutral state by the upper leaf spring and the lower leaf spring fixedly held by the housing so as to face each other with being spaced apart from each other in the height direction. In addition, when the operation shaft performs the tilting movement, the upper leaf spring and the lower leaf spring do not slide on other members in the housing. Therefore, even if the user repeatedly applies the tilting operation to the multi-directional input device of the present invention, the upper leaf spring and the lower leaf spring do not wear away, and thereby it is possible to significantly increase a product life of the multi-directional input device. Further, reaction force characteristics against the tilting operation to the operation shaft, which is provided by the upper leaf spring and the lower leaf spring facing each other with being spaced apart from each other in the height direction, become non-linear characteristics which are preferable as a controller of a game machine.

[0014] Further, in the multi-directional input device according to the second aspect of the present invention, an extending direction of each arm portion of the upper leaf spring is opposite to an extending direction of each arm portion of the lower leaf spring. Thus, the upper leaf spring and the lower leaf spring are configured to be vertically symmetrical to each other (configured so that its front and back are symmetrical). Thus, an anisotropy of a stiffness of the upper leaf spring and an anisotropy of a stiffness of the lower leaf spring cancel out each other. As a result, a stiffness of the holding mechanism obtained by combining the stiffnesses of the upper leaf spring and the stiffnesses of the lower leaf spring does not have anisotropy. Thus, in the multi-directional input device of the present invention, reaction force against the tilting operation to the operation shaft does not have anisotropy, and thereby the multi-directional input device can be preferably used as a joystick for the controller of the game machine.

[0015] Further, in the multi-directional input device according to the third aspect of the present invention, the operation shaft is elastically held by the upper leaf spring and the lower leaf spring so that the operation shaft can be displaced in the height direction. Thus, it is possible to displace the operation shaft toward the lower side according to the pressing operation applied to the operation shaft from the user to press the push switch. Therefore, the multi-directional input device can accept not only the tilting operation with respect to the operation shaft from the user but also the pressing operation with respect to the operation shaft from the user.

[0016] Further, in the multi-directional input device according to the fourth aspect of the present invention, the inner frames of the upper leaf spring and the lower leaf spring are connected to the spring connection portion of the operation shaft in the state that the inner frames of the upper leaf spring and the lower leaf spring are spaced apart from each other in the height direction. The holding mechanism is configured by using the upper leaf spring and the lower leaf spring which are spaced apart from each other in the height direction and each of which has a torsional stiffness and a lateral stiffness which are significantly different from each other as described above, and thereby the lateral stiffness of the holding mechanism becomes significantly larger than the torsional stiffness of the holding mechanism. As a result, it is possible to make the reaction force characteristic with respect to the tilting operation to the operation shaft preferable for being used as the joystick used for the controller of the game machine.

[0017] Further, in the multi-directional input device according to the fifth aspect of the present invention, an upper housing is provided between the outer frame of the upper leaf spring and the outer frame of the lower leaf spring, and the bush is provided between the inner frame of the upper leaf spring and the inner frame of the lower leaf spring. Thus, the outer frame of the upper leaf spring faces the outer frame of the lower leaf spring in parallel, and the inner frame of the upper leaf spring faces the inner frame of the lower leaf spring in parallel. Namely, the upper leaf spring and the lower leaf spring face each other in parallel. With this configuration, a separation distance between the upper leaf spring and the lower leaf spring can be kept constant, and thereby it is possible to stabilize the reaction force characteristic against the tilting operation to the operation shaft.

[0018] Further, in the multi-directional input device according to the sixth aspect of the present invention, the upper leaf spring and the lower leaf spring are configured and arranged so that the upper leaf spring and the lower leaf spring have the planar shapes which are upside down relative to each other in the planar view from the height direction. Thus, the anisotropy of the stiffness of the upper leaf spring and the anisotropy of the stiffness of the lower leaf spring cancel out each other. As a result, the stiffness of the holding mechanism obtained by combining the stiffnesses of the upper leaf spring and the stiffnesses of the lower leaf spring does not have anisotropy. The reaction force against the tilting operation to the operation shaft which is elastically held by the holding mechanism does not have anisotropy, and thereby the multi-directional input device can be preferably used as the joystick for the controller of the game machine.

[0019] Further, in the multi-directional input device according to the seventh aspect of the present invention, when the straight line is drawn toward the outer side from the center of the inner frame to the arbitrary point on the inner peripheral surface of the outer frame, each of the upper leaf spring and the lower leaf spring is configured so that the at least one of the spring portions and the two spaces which are respectively located on the outer side and the inner side of the at least one of the spring portions and in which the at least one of the spring portions does not exist are always located on the straight line. The two spaces respectively located on the outer side and the inner side of the at least one of the spring portions allow the at least one of the spring portions to elastically buckle (elastically bend) in the height direction. Thus, it is possible to configure the upper leaf spring and the lower leaf spring so that a torsional stiffness with respect to a torsional-direction displacement that the inner frame is tilted with respect to the outer frame is significantly less than a lateral stiffness with respect to a lateral-direction displacement of the inner frame with respect to the outer frame. As a result, it is possible to make the reaction force characteristic with respect to the tilting operation to the operation shaft preferable for being used as the joystick used for the controller of the game machine.

[0020] Further, in the multi-directional input device according to the tenth aspect of the present invention, the first connecting portions, the second connecting portions, and the plurality of arm portions of the plurality of spring portions of the plurality of upper leaf springs which are held so as to be spaced apart from each other in the height direction overlap each other in the vertical direction. Further, the first connecting portions, the second connecting portions, and the plurality of arm portions of the plurality of spring portions of the plurality of lower leaf springs which are held so as to be spaced apart from each other in the height direction overlap each other in the vertical direction. With this configuration, when the operation shaft is tilted, the arm portions of the plurality of upper leaf springs or the plurality of lower leaf springs located on an upper side and the lower side are subjected to the same stresses at the same position and the same torsional motion is generated, so that it is possible to prevent the arm portions located on the upper side and the lower side from interfering with each other.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] [Fig. 1] Fig. 1 is a schematic cross-sectional view of a conventional multi-directional input device. [Fig. 2] Fig. 2 is a graph showing reaction force characteristics of the multi-directional input device shown in Fig. 1 against a tilting operation to an operation shaft. [Fig. 3] Fig. 3 is a perspective view of a multi-directional input device according to an embodiment of the present invention. [Fig. 4] Fig. 4 is a cross-sectional perspective view of the multi-directional input device shown in Fig. 3. [Fig. 5] Fig. 5 is a longitudinal cross-sectional view of the multi-directional input device shown in Fig. 3. [Fig. 6] Fig. 6 is an exploded perspective view of the multi-directional input device shown in Fig. 3. [Fig. 7] Fig. 7 is an exploded perspective view of a push switch shown in Fig. 6. [Fig. 8] Fig. 8 is a perspective view showing a pressing member shown in Fig. 7 viewed from another angle. [Fig. 9] Fig. 9 is a perspective view showing a lower housing shown in Fig. 6 viewed from another angle. [Fig. 10] Fig. 10 is an exploded perspective view of an operation shaft assembly shown in Fig. 6. [Fig. 11] Fig. 11 is a perspective view showing a first pivot member shown in Fig. 6 viewed from another angle. [Fig. 12] Fig. 12 is an exploded perspective view of the operation shaft and a holding mechanism shown in Fig. 6. [Fig. 13] Fig. 13 is an exploded perspective view of an upper leaf spring assembly shown in Fig. 12. [Fig. 14] Fig. 14 is a planar view of the upper leaf spring shown in Fig. 13. [Fig. 15] Fig. 15 is an exploded perspective view of a lower leaf spring assembly shown in Fig. 12. [Fig. 16] Fig. 16 is a planar view of a lower leaf spring shown in Fig. 15. [Fig. 17] Fig. 17 is a cross-sectional perspective view for explaining a state that the operation shaft is held by the holding mechanism. [Fig. 18] Fig. 18 is a diagram for explaining a dynamic model of a displacement of the operation shaft held by the holding mechanism. [Fig. 19] Fig. 19 is a diagram showing stress distributions of the upper leaf spring and the lower leaf spring in an initial state of a tilting movement. [Fig. 20] Fig. 20 is a diagram showing stress distributions of the upper leaf spring and the lower leaf spring in a second state of the tilting movement. [Fig. 21] Fig. 21 is a diagram for explaining reaction force characteristics against the tilting operation to the operation shaft. DETAILED DESCRIPTION

[0022] Hereinafter, a multi-directional input device of the present invention will be described with reference to a preferred embodiment shown in Figs. 3 to 21. Note that each of the figures referred in the following description is a schematic diagram prepared for explaining the present invention. A dimension (such as a length, a width, and a thickness) of each component shown in the drawings is not necessarily identical to an actual dimension. Further, the same reference numbers are used throughout the drawings to refer to the same or similar elements. In the following description, the positive direction of the Z axis of each figure may be referred to as "an upper side", and the negative direction of the Z axis of each figure may be referred to as "a lower side".

[0023] Fig. 3 is a perspective view of the multi-directional input device according to the embodiment of the present invention. Fig. 4 is a cross-sectional perspective view of the multi-directional input device shown in Fig. 3. Fig. 5 is a longitudinal cross-sectional view of the multi-directional input device shown in Fig. 3. Fig. 6 is an exploded perspective view of the multi-directional input device shown in Fig. 3. Fig. 7 is an exploded perspective view of a push switch shown in Fig. 6. Fig. 8 is a perspective view showing a pressing member shown in Fig. 7 viewed from another angle. Fig. 9 is a perspective view showing a lower housing shown in Fig. 6 viewed from another angle. Fig. 10 is an exploded perspective view of an operation shaft assembly shown in Fig. 6. Fig. 11 is a perspective view showing a first pivot member shown in Fig. 6 viewed from another angle. Fig. 12 is an exploded perspective view of the operation shaft and a holding mechanism shown in Fig. 6. Fig. 13 is an exploded perspective view of an upper leaf spring assembly shown in Fig. 12. Fig. 14 is a planar view of the upper leaf spring shown in Fig. 13. Fig. 15 is an exploded perspective view of a lower leaf spring assembly shown in Fig. 12. Fig. 16 is a planar view of a lower leaf spring shown in Fig. 15. Fig. 17 is a cross-sectional perspective view for explaining a state that the operation shaft is held by the holding mechanism. Fig. 18 is a diagram for explaining a dynamic model of a displacement of the operation shaft held by the holding mechanism. Fig. 19 is a diagram showing stress distributions of the upper leaf spring and the lower leaf spring in an initial state of a tilting movement. Fig. 20 is a diagram showing stress distributions of the upper leaf spring and the lower leaf spring in a second state of the tilting movement. Fig. 21 is a diagram for explaining reaction force characteristics against the tilting operation to the operation shaft.

[0024] A multi-directional input device 1 according to the embodiment of the present invention shown in Figs. 3 to 6 should be mounted on a circuit board of an arbitrary electronic device. When a tilting operation and a pressing operation are applied to the multi-directional input device 1 from a user, the multi-directional input device 1 inputs direction information according to the tilting operation and pressing information according to the pressing operation to the electronic device. In one embodiment, the multi-directional input device 1 has a vertical length of 18 mm, a horizontal length of 18 mm, and a height of 18 mm, and receives the tilting operation and the pressing operation of about 25 degrees in an arbitrary direction from the user. Typically, the multi-directional input device 1 can be used as a joystick of a handheld controller of a game machine.

[0025] As shown in Fig. 6, the multi-directional input device 1 includes a lower cover 2L to be placed on the circuit board of the arbitrary electronic device, an upper cover 2U coupled with the lower cover 2L, a circuit board 3 on which electronic components of the multi-directional input device 1 are mounted, a push switch 4 provided on the circuit board 3, a lower housing 5 fixed on the circuit board 3, an operation shaft assembly 6 containing an upper housing 61, a first pivot member 62a held by the upper housing 61 so that the first pivot member 62a can be pivotally moved around a first axis direction, a second pivot member 62b held by the upper housing 61 so that the second pivot member 62b can be pivotally moved around a second axis direction perpendicular to the first axis direction, and an operation shaft 63 which is held in a neutral state and to which the tilting operation and the pressing operation are applied from the user, and a detection mechanism 7 for detecting a pivot angle of each of the first pivot member 62a and the second pivot member 62b. Here, the words of "neutral state" of the operation shaft 63 refers to a state that the operation shaft 63 remains at rest at a steady position in an upright posture in which an axis direction of the operation shaft 63 substantially coincides with the height direction.

[0026] The lower cover 2L has a function of supporting the circuit board 3 from the lower side to support an inner structure of the multi-directional input device 1 from the upper side and the lower side together with the upper cover 2U. The lower cover 2L is formed from hard non-magnetic material such as stainless steel. The lower cover 2L includes a bottom plate 21, a plurality of through-holes 22 formed in the bottom plate 21, and four lower cover pieces 23 extending from the bottom plate 21 toward the upper side. The bottom plate 21 is a plate-like portion having a planar shape corresponding to a planar shape of the circuit board 3 (in the illustrated aspect, an approximately octagonal planar shape). The bottom plate 21 should be positioned between the circuit board 3 and the circuit board of the electronic device when the multi-directional input device 1 is mounted on the circuit board of the electronic device. The plurality of through-holes 22 are respectively formed at positions respectively corresponding to a plurality of terminal pins 31 of the circuit board 3 for enabling the terminal pins 31 to respectively pass through the bottom plate 21 in the height direction. The lower cover 2L is attached to the circuit board 3 from the lower side by arbitrary fixing means such as an adhesive so that each of the terminal pins 31 is passed through the corresponding through-hole 22. The four lower cover pieces 23 are plate-like portions linearly extending from two pairs of opposite sides of the bottom plate 21 toward the upper side, respectively. The four lower cover pieces 23 are respectively coupled with four upper cover pieces 27 of the upper cover 2U by jointing such as welding, and thereby the lower cover 2L and the upper cover 2U are firmly integrated with each other. Since the inner structure of the multi-directional input device 1 is supported from the upper side and the lower side by the lower cover 2L and the upper cover 2U firmly integrated with each other as described above, it is possible to reliably prevent the inner structure of the multi-directional input device 1 from swinging (rattling) in the height direction.

[0027] The upper cover 2U includes an upper plate 24, an opening 25 formed in the upper plate 24, four wall portions 26 extending from the upper plate 24 toward the lower side, and the four upper cover pieces 27 extending from the upper plate 24 toward the lower side. The upper plate 24 is a plate-like portion having a planar shape corresponding to the planar shape of the bottom plate 21 of the lower cover 2L. The opening 25 is a circular opening formed in a central portion of the upper plate 24. As shown in Fig. 3, an operation portion 631 of the operation shaft 63 protrudes toward the upper side through the opening 25. Referring back to Fig. 6, the four wall portions 26 are plate-like portions formed on an outer edge of the upper plate 24 at regular angular intervals of 90 degrees so as to linearly extend from the upper plate 24 toward the lower side. The four upper cover pieces 27 are plate-like portions formed on the outer edge of the upper plate 24 at regular angular intervals of 90 degrees so as to linearly extend from the upper plate 24 toward the lower side. The four wall portions 26 and the four upper cover pieces 27 linearly extend toward the lower side with being spaced apart from each other. Thus, the wall portions 26 and the upper cover pieces 27 are alternately provided on the upper plate 24 along a circumferential direction of the upper plate 24.

[0028] The circuit board 3 is a plate-like rigid circuit board formed from material and a configuration known in the electronic device field. The circuit board 3 includes a circuit pattern (not shown) covered by a protective layer, and the plurality of terminal pins 31 passing through the circuit board 3. Two magnetic sensors (for example, Hall IC sensors) 71 of the detection mechanism 7 and the push switch 4 are mounted on the circuit board 3. The two magnetic sensors 71 and the push switch 4 are electrically connected to the corresponding terminal pins 31 through the circuit pattern, respectively. The terminal pins 31 respectively corresponding to the two magnetic sensors 71 and the push switch 4 are connected to corresponding terminals of the circuit board of the electronic device. With this configuration, the electronic device can receive input from the multi-directional input device 1.

[0029] The push switch 4 is a switch which should be pressed according to a downward displacement of the operation shaft 63 when the pressing operation is applied to the operation shaft 63 from the user and the operation shaft 63 is displaced toward the lower side. When pressing force exceeding operating force of the push switch 4 is applied from the user with respect to the operation shaft 63, the push switch 4 is turned on. After that, when the pressing force applied from the user is released, the push switch 4 is turned off. As shown in Figs. 4 and 5, in a state that the multi-directional input device 1 is assembled, the push switch 4 is provided on the circuit board 3 so as to be located immediately below the operation shaft 63. When the operation shaft 63 is displaced toward the lower side according to the pressing operation applied from the user, the push switch 4 is pressed by the operation shaft 63.

[0030] As shown in Fig. 7, the push switch 4 includes a central contact 41 formed on the circuit board 3 so as to be exposed toward the outside, an annular outer contact 42 formed on the circuit board 3 with being spaced apart from the central contact 41 so as to surround the central contact 41, a dome-shaped movable contact 43, a hollow elastic member 44 provided on the circuit board 3 so as to surround the movable contact 43, and a pressing member 45 provided on the elastic member 44.

[0031] The central contact 41 and the outer contact 42 are formed on the circuit board 3 so as to be insulated from each other. The central contact 41 is formed on a substantially central portion of the circuit board 3 so as to have a circular shape. The central contact 41 is arranged so as to be concentric with the outer contact 42. A state that the central contact 41 and the outer contact 42 are not electrically connected to each other is an off state of the push switch 4. On the other hand, a state that the central contact 41 and the outer contact 42 are electrically connected to each other through the movable contact 43 is an on state of the push switch 4. The movable contact 43 is an upper convex dome-shaped member formed from conductive material. For example, the movable contact 43 can be obtained by punching and bending a thin metal plate. The movable contact 43 includes a central movable portion 431 and an outer edge portion 432 surrounding an outer edge of the central movable portion 431.

[0032] The central movable portion 431 has a circular dome shape protruding toward the upper side in a natural state. The central movable portion 431 can be elastically deformed so as to protrude toward the lower side when pressing force is applied to the central movable portion 431 from the upper side. The outer edge portion 432 is an annular portion linearly extending from the outer edge of the central movable portion 431 toward the outer and lower side. The outer edge portion 432 has an outer diameter which is larger than or equal to an inner diameter of the outer contact 42 and less than or equal to an outer diameter of the outer contact 42 in a planar view from the height direction. The movable contact 43 is provided on the circuit board 3 so that the movable contact 43 is concentric with the central contact 41 and the outer contact 42 and the outer edge portion 432 contacts with the outer contact 42. The movable contact 43 may be fixed on the circuit board 3 by arbitrary fixing means such as an adhesive and a retainer in order to prevent the movable contact 43 from shifting on the circuit board 3.

[0033] As shown in Figs. 4 and 5, when the operation shaft 63 is in the neutral state, the outer edge portion 432 contacts with the outer contact 42. The central movable portion 431 faces the central contact 41 with a gap therebetween, and does not contact the central contact 41. Thus, when the operation shaft 63 is in the neutral state, the central contact 41 and the outer contact 42 are not electrically connected to each other, and the push switch 4 is in the off state. On the other hand, when the user applies the pressing operation with respect to the operation shaft 63, downward pressing force is applied to the central movable portion 431 through the operation shaft 63 and the pressing member 45. When the pressing force applied to the central movable portion 431 becomes equal to or larger than a predetermined magnitude, the central movable portion 431 is elastically deformed rapidly so as to protrude toward the lower side and then contacts with the central contact 41. In this state, the movable contact 43 serves as an electrical path between the central contact 41 and the outer contact 42, and thereby the central contact 41 and the outer contact 42 are electrically connected to each other. With this operation, the push switch 4 is turned on.

[0034] Referring back to Fig. 7, the elastic member 44 has a function of elastically supporting the pressing member 45 from the lower side. The elastic member 44 has a cylindrical shape whose inner diameter is larger than the outer diameter of the outer contact 42 in the planar view from the height direction and whose height is higher than a height of the movable contact 43. Typically, a coil spring or a wave washer formed from non-magnetic spring material (e.g., stainless steel) can be used as the elastic member 44.

[0035] As shown in Figs. 4 and 5, the elastic member 44 is provided on the circuit board 3 so as to be concentric with the central contact 41 and the outer contact 42. Thus, the central contact 41, the outer contact 42, and the movable contact 43 are located in an inner space of the elastic member 44. The elastic member 44 may be fixed on the circuit board 3 by arbitrary fixing means such as an adhesive and a retainer in order to prevent the elastic member 44 from shifting on the circuit board 3.

[0036] Referring back to Fig. 7, the pressing member 45 has a function of applying uniform pressing force with respect to the central movable portion 431 of the movable contact 43. The pressing member 45 is formed from hard non-magnetic material such as polyacetal resin. When the pressing operation is applied to the operation shaft 63 from the user, the pressing member 45 is pressed toward the lower side by the operation shaft 63 and then makes point contact with the central movable portion 431 to apply the uniform pressing force to the central movable portion 431.

[0037] As shown in Figs. 7 and 8, the pressing member 45 includes a disk-like body portion 451, a tapered portion 452 formed on an upper surface of the body portion 451, a flat pressed surface 453 formed on a top portion of the tapered portion 452, an annular flange portion 454 extending from a lower end portion of an outer edge of the body portion 451 toward the outer side, an annular receiving groove 455 formed on a lower surface of the body portion 451, a circular recessed portion 456 formed on the lower surface of the body portion 451, and a pressing protrusion 457 protruding from a center of the circular recessed portion 456 toward the lower side.

[0038] The body portion 451 is a plate-like portion whose upper surface and lower surface are flat surfaces perpendicular to the height direction and which has a circular shape in the planar view from the height direction. The tapered portion 452 is a truncated cone portion which is formed on a central portion of the upper surface of the body portion 451 so as to be concentric with the body portion 451 and have a diameter gradually decreasing from the lower side toward the upper side. The pressed surface 453 is a flat surface formed on the top portion of the tapered portion 452 so as to be perpendicular to the height direction. When the pressing operation is applied to the operation shaft 63 from the user, the operation shaft 63 presses the pressed surface 453 toward the lower side, and thereby the tapered portion 452 is displaced toward the lower side. The flange portion 454 is an annular portion protruding from the lower end portion of the outer edge of the body portion 451 toward the outer side and surrounding the outer edge of the body portion 451. As shown in Figs. 4 and 5, the flange portion 454 engages with the lower housing 5 to restrict an upward displacement of the pressing member 45.

[0039] Referring back to Fig. 8, the receiving groove 455 is an annular recess formed on an area of the lower surface of the body portion 451 adjacent to the flange portion 454. The receiving groove 455 is formed so that an upper end portion of the elastic member 44 can be fitted into the receiving groove 455. By placing the pressing member 45 on the elastic member 44 so as to fit the upper end portion of the elastic member 44 into the receiving groove 455, the pressing member 45 is elastically supported by the elastic member 44 from the lower side. The circular recessed portion 456 is formed on the central portion of the lower surface of the body portion 451 so as to be concentric with the body portion 451 to facilitate a downward displacement of the tapered portion 452. The pressing protrusion 457 is a columnar portion formed on the center of the circular recessed portion 456 so as to protrude toward the lower side and be concentric with the circular recessed portion 456. In addition, a center of the pressing protrusion 457 and a center of the pressed surface 453 are aligned on one straight line. A lower surface of the pressing protrusion 457 is a flat surface perpendicular to the height direction. As shown in Figs. 4 and 5, the pressing protrusion 457 faces the central movable portion 431 of the movable contact 43 with a gap therebetween in the natural state. When the pressing member 45 is pressed toward the lower side by the operation shaft 63 and the tapered portion 452 is displaced toward the lower side, the lower surface of the pressing protrusion 457 makes point contact with the central movable portion 431 of the movable contact 43 to apply the uniform pressing force to the central movable portion 431. With this configuration, it is possible to stabilize deformation characteristics of the movable contact 43.

[0040] As shown in Fig. 7, all of the central contact 41, the outer contact 42, the movable contact 43, the elastic member 44, and the pressing member 45, which are components of the push switch 4, are arranged on the circuit board 3 so as to be rotationally symmetrical to each other and concentric to each other. Further, as shown in Figs. 4 and 5, when the operation shaft 63 is in the neutral state, an axis center of the operation shaft 63 and centers of all of the components of the push switch 4 are located on the one straight line. Thus, the push switch 4 is provided immediately below the operation shaft 63.

[0041] Referring back to Fig. 6, the lower housing 5 has functions of containing the push switch 4 provided on the circuit board 3 therein and supporting the operation shaft assembly 6 from the lower side to fix the operation shaft assembly 6 with respect to the circuit board 3. The lower housing 5 is formed from hard non-magnetic material such as polybutylene terephthalate. As shown in Figs. 6 and 9, the lower housing 5 includes a cylindrical body portion 51, a first circular recessed portion 52 formed on an upper surface of the body portion 51, a second circular recessed portion 53 formed on the first circular recessed portion 52, a circular through-hole 54 formed so as to pass through the second circular recessed portion 53 in the height direction, an annular locking portion 55 extending from an inner surface of the through-hole 54 toward the inner side, two containing portion 56a, 56b formed in the body portion 51 so as to pass through the body portion 51 in the height direction, and a relief portion 57 formed on a lower surface of the body portion 51.

[0042] As shown in Fig. 6, the body portion 51 is a cylindrical portion which is placed on the circuit board 3 and has a planar outer shape corresponding to the planar shape of the circuit board 3. Further, the upper surface and the lower surface of the body portion 51 are flat surfaces perpendicular to the height direction. The body portion 51 includes a tapered surface 511 provided on an outer peripheral surface of the body portion 51 and extending from an upper end portion of the body portion 51 toward the lower and outer side, an arcuate surface 512 located on the lower side of the tapered surface 511, four flat abutting surfaces 513 respectively formed on both X direction side surfaces and both Y direction side surfaces of the body portion 51, and a cutout portion 514 formed at a +Y direction side lower end portion of the body portion 51. As shown in Fig. 3, the tapered surface 511 is a portion on which the four wall portions 26 of the upper cover 2U are placed. Since the tapered surface 511 is a flat surface extending toward the lower and outer side, the four wall portions 26 are opened toward the outer side when the four wall portions 26 are pressed against the tapered surface 511 to firmly sandwich the body portion 51 from the outer side. With this configuration, it is possible to prevent the lower housing 5 from swinging (rattling) on the circuit board 3.

[0043] Referring back to Fig. 6, the arcuate surface 512 is an arcuate portion linearly extending from a lower end portion of the tapered surface 511 toward the lower side. The four abutting surfaces 513 are flat surfaces perpendicular to the X direction or the Y direction. The four abutting surfaces 513 can be respectively formed by linearly cutting out both X direction side surfaces and both Y direction side surfaces of the body portion 51 along the height direction. As shown in Fig. 3, the four abutting surfaces 513 are portions respectively making surface-contacts with the four upper cover pieces 27 of the upper cover 2U. Since the four abutting surfaces 513 and the four upper cover pieces 27 make the surface-contacts, the lower housing 5 is firmly held by the upper cover 2U. Further, as shown in Fig. 3, two of the terminal pins 31 of the circuit board 3 located on the +Y direction side are located below the cutout portion 514 in order to prevent the body portion 51 from interfering with the two of the terminal pins 31 of the circuit board 3 located on the +Y direction side.

[0044] Referring back to Fig. 6, the first circular recessed portion 52 is formed on the central portion of the upper surface of the body portion 51 so as to be concentric with the body portion 51. The second circular recessed portion 53 is formed on the central portion of the first circular recessed portion 52 so as to be concentric with the first circular recessed portion 52. The through-hole 54 is a circular opening formed in the substantially central portion of the second circular recessed portion 53 so as to pass through the second circular recessed portion 53 in the height direction. The locking portion 55 is an annular portion protruding from an upper end portion of the inner peripheral surface of the through-hole 54 toward the inner side. As shown in Figs. 4 and 5, a diameter of the through-hole 54 is substantially equal to a diameter of the flange portion 454 of the pressing member 45, and an inner diameter of the locking portion 55 is substantially equal to an outer diameter of the body portion 451 of the pressing member 45. Thus, in the state that the multi-directional input device 1 is assembled, the body portion 451 is fitly engaged with the locking portion 55 to prevent the pressing member 45 from swinging in the lateral direction in the lower housing 5. Further, since the locking portion 55 engages with the flange portion 454, the upward displacement of the pressing member 45 is restricted.

[0045] Referring back to Fig. 9, the relief portion 57 is a recess formed on the lower surface of the body portion 451. As shown in Figs. 4 and 5, in the state that the multi-directional input device 1 is assembled, the plurality of terminal pins 31 of the circuit board 3 are located in the relief portion 57, so that the body portion 51 and the plurality of terminal pins 31 do not interfere with each other. Referring back to Figs. 6 and 9, the containing portion 56a is an opening formed in a portion of the body portion 51 located on the +Y direction side of the first circular recessed portion 52 so as to pass through the body portion 51 in the height direction. Similarly, the containing portion 56b is an opening formed on a portion of the body portion 51 located on the +X direction side of the first circular recessed portion 52 so as to pass through the body portion 51 in the height direction. A magnet assembly 72 (see Fig. 6) attached to the first pivot member 62a is contained in the containing portion 56a so that the magnet assembly 72 can be displaced in the X direction. Similarly, another magnet assembly 72 attached to the second pivot member 62b is contained in the containing portion 56b so that the other magnet assembly 72 can be displaced in the Y direction.

[0046] Referring back to Fig. 6, the operation shaft assembly 6 has a function of elastically holding the operation shaft 63 in the neutral state to perform the tilting movement of the operation shaft 63 according to the tilting operation applied from the user, and a function of displacing the operation shaft 63 toward the lower side according to the pressing operation applied from the user. The operation shaft assembly 6 is fixed on the upper surface of the body portion 51 of the lower housing 5 by any fixing means such as an adhesive and a retainer. As shown in Fig. 10, the operation shaft assembly 6 includes the upper housing 61 provided on the lower housing 5, the first pivot member 62a held by the upper housing 61 so that the first pivot member 62a can be pivotally moved around the first axis direction (the Y direction), the second pivot member 62b held by the upper housing 61 so that the second pivot member 62b can be pivotally moved around the second axis direction (the X direction) perpendicular to the first axis direction, the operation shaft 63 which can perform the tilting movement according to the tilting operation applied from the user and can be displaced toward the lower side according to the pressing operation applied from the user, two shaft members 64a serving as pivot shafts for the first pivot member 62a, two shaft members 64b serving as pivot shafts for the second pivot member 62b, a housing cover 65 attached to the upper housing 61 from the upper side, and a holding mechanism 66 held by the upper housing 61 to elastically hold the operation shaft 63 in the neutral state.

[0047] The upper housing 61 is a cylindrical member provided on the lower housing 5 and fixed with respect to the circuit board 3. Similar to the lower housing 5, the upper housing 61 is formed from hard non-magnetic material. The upper housing 61 has a function of holding the first pivot member 62a, the second pivot member 62b, and the holding mechanism 66. The upper housing 61 includes a cylindrical body portion 611, a pair of protruding surfaces 612 provided on an outer peripheral surface of the body portion 611 so as to face each other, four shaft holes 613 formed in the outer peripheral surface of the body portion 611, and six locking pieces 614 provided on an inner peripheral surface of the body portion 611.

[0048] The body portion 611 defines a cylindrical inner space linearly extending in the height direction. An upper surface and a lower surface of the body portion 611 are flat surfaces perpendicular to the height direction. The pair of protruding surfaces 612 are provided on the outer peripheral surface of the body portion 611 at angular intervals of 180 degrees so as to face each other. Each of the protruding surfaces 612 protrudes from the outer peripheral surface of the body portion 611 toward the outer side. An outer surface of each of the protruding surfaces 612 is a flat surface perpendicular to the X direction. An upper surface and a lower surface of the outer surface of each of the protruding surfaces 612 are flat surfaces perpendicular to the height direction and are respectively located on the same planes as the upper surface and the lower surface of the body portion 611, and thus they are respectively continuous with the upper surface and the lower surface of the body portion 611.

[0049] The four shaft holes 613 are circular openings formed in the outer peripheral surface of the body portion 611 at regular angular intervals of 90 degrees so as to pass through the body portion 611. In this regard, each of the two shaft holes 613 located on the +X direction side and the -X direction side is formed so as to pass through not only the body portion 611 but also the protruding surface 612. The two shaft members 64a are respectively inserted into and fixed to the two shaft holes 613 located on the +Y direction side and the -Y direction side, and thereby the two shaft members 64a serve as the pivot shafts for the first pivot member 62a. Similarly, the two shaft members 64b are respectively inserted into and fixed to the two shaft holes 613 located on the +X direction side and the -X direction side, and thereby the two shaft members 64b serve as the pivot shafts for the second pivot member 62b. The six locking pieces 614 are plate-like members elongated in the height direction and provided on the inner peripheral surface of the body portion 611 at regular angular intervals of 60 degrees. A length of each locking piece 614 in the height direction is longer than a length of the body portion 611 in the height direction. An upper end portion and a lower end portion of each locking piece 614 protrude from the body portion 611 in the height direction. Further, hook structures are respectively formed on outer surfaces of the upper end portion and the lower end portion of each locking piece 614. As shown in Fig. 4, the hook structures of the upper end portion and the lower end portion of each locking piece 614 sandwich the body portion 611 from the upper side and the lower side.

[0050] Referring back to Fig. 10, the first pivot member 62a is held by the upper housing 61 so that the first pivot member 62a can be pivotally moved around the first axial direction (the Y direction). The second pivot member 62b is held by the upper housing 61 so that the second pivot member 62b can be pivotally moved around the second axial direction (the X direction) perpendicular to the first axial direction (the Y direction). Since the first pivot member 62a and the second pivot member 62b have the same structure except that attachment postures with respect to the upper housing 61 are different from each other, the configuration of the first pivot member 62a will be described in detail as a representative.

[0051] As shown in Fig. 11, the first pivot member 62a includes an arch portion 621 protruding toward the upper side, a slit hole 622 formed in the arch portion 621, a pair of horizontally extending portions 623 respectively extending from both end portions of the arch portion 621, a pair of downwardly extending portions 624 respectively extending from the pair of horizontally extending portions 623 toward the lower side, a pair of shaft holes 625 respectively formed in the pair of downwardly extending portions 624, and a bearing portion 626 formed at a lower end portion of one of the downwardly extending portions 624.

[0052] The arch portion 621 is a portion having a curved shape protruding toward the upper side and elongated in the Y direction. The arch portion 621 of the first pivot member 62a contacts with a pair of second locking surfaces 635 (see Figs. 12 and 17) of the operation shaft 63 from the upper side. The arch portion 621 of the second pivot member 62b engages with a pair of first locking surfaces 634 (see Fig. 12) of the operation shaft 63 from the upper side. With this configuration, it is possible to restrict an upward displacement of the operation shaft 63 with respect to the upper housing 61. Referring back to Fig. 11, the slit hole 622 is an elongated through-hole extending from one end portion toward another end portion of the arch portion 621 along a longitudinal direction of the arch portion 621 so as to pass through the arch portion 621 in the height direction. The operation shaft 63 is passed through the slit hole 622, and thus the tilting movement of the operation shaft 63 along the longitudinal direction of the arch portion 621 is enabled. Lengths of the arch portion 621 and the slit hole 622 in the longitudinal direction are set depending on a maximum value of a tilt angle of the operation shaft 63. In the illustrated aspect, the tilting movement of about 25 degrees of the operation shaft 63 is enabled.

[0053] Each of the horizontally extending portions 623 is a plate-like portion linearly extending from the end portion of the arch portion 621 toward the outer side. One end portion of the horizontally extending portion 623 is connected to the end portion of the arch portion 621 and another end portion of the horizontally extending portion 623 is connected to the downwardly extending portion 624. Each of the downwardly extending portions 624 is a plate-like portion linearly extending from the other end portion of the horizontally extending portion 623 toward the lower side. The pair of shaft holes 625 are respectively formed in the pair of downwardly extending portions 624 so as to face each other. The two shaft members 64a are respectively inserted into and fixed to the two shaft holes 613 of the upper housing 61 respectively located on the +Y direction side and the -Y direction side in a state that the two shaft members 64a are respectively passed through the pair of shaft holes 625 of the first pivot member 62a. As a result, the first pivot member 62a is held by the upper housing 61 so that the first pivot member 62a can be pivotally moved around the first axial direction (the Y direction). Similarly, the two shaft members 64b are respectively inserted into and fixed to the two shaft holes 613 of the upper housing 61 respectively located on the +X direction side and the -X direction side in a state that the two shaft members 64b are respectively passed through the pair of shaft holes 625 of the second pivot member 62b. As a result, the second pivot member 62b is held by the upper housing 61 so that the second pivot member 62b can be pivotally moved around the second axial direction (the X direction). The bearing portion 626 is an elongated circular opening formed in the lower end portion of the one of the downwardly extending portions 624 so as to be opened toward the lower side. An after-mentioned magnet assembly 72 of the detection mechanism 7 is supported by the bearing portion 626.

[0054] Referring back to Fig. 10, the operation shaft 63 has a function of pivotally moving the first pivot member 62a and the second pivot member 62b according to the tilting operation applied from the user, and a function of displacing toward the lower side according to the pressing operation applied from the user to press the push switch 4. As shown in Fig. 12, the operation shaft 63 is a rod-like member extending in the height direction. The operation shaft 63 includes the operation portion 631 which protrudes from the opening 25 of the upper cover 2U toward the upper side and should be operated by the user, a spring connection portion 632 extending from a lower end portion of the operation portion 631 toward the lower side, a pair of D-cut surfaces 633 formed on outer peripheral surfaces of the operation portion 631 and the spring connection portion 632, the pair of first locking surfaces 634 extending from the lower end portion of the operation portion 631 toward the outer side, the pair of second locking surfaces 635 (see Fig.17) formed on the outer peripheral surface of the spring connection portion 632, a circular flange portion 636 extending from the outer peripheral surface of the spring connection portion 632 toward the outer side, a press-fitting hole 637 (see Figs. 4 and 5) formed on a lower surface of the spring connection portion 632, and a pressing portion 638 attached to the lower surface of the spring connection portion 632 by press-fitting the pressing portion 638 into the press-fitting hole 637.

[0055] The operation portion 631 is a columnar portion linearly extending in the height direction. The spring connection portion 632 is connected to the lower end portion of the operation portion 631. The spring connection portion 632 is a columnar portion linearly extending from the lower end portion of the operation portion 631 toward the lower side. The spring connection portion 632 is formed so as to be concentric with the operation portion 631 and has a diameter larger than a diameter of the operation portion 631. The pair of D-cut surfaces 633 can be formed by linearly cutting out a +X direction side portion and a -X direction side portion of the outer peripheral surface of the operation portion 631 and a +X direction side portion and a -X direction side portion of the outer peripheral surface of the spring connection portion 632 in the height direction. The pair of D-cut surfaces 633 are flat surfaces perpendicular to the X direction and face each other. As shown in Fig. 3, in the state that the multi-directional input device 1 is assembled, the pair of D-cut surfaces 633 make surface-contacts with the slit hole 622 of the first pivot member 62a. With this configuration, even if the user applies a torsion operation with respect to the operation shaft 63 so as to rotate the operation shaft 63 around the axis of the operation shaft 63, engagements between the pair of D-cut surfaces 633 and the slit hole 622 prevent rotation of the operation shaft 63.

[0056] Referring back to Fig. 12, the pair of first locking surfaces 634 are an upper surface of the spring connection portion 632 and are flat surface perpendicular to the height direction. The pair of first locking surfaces 634 linearly extend from the lower end portion of the operation portion 631 in the Y direction. As described above, the arch portion 621 of the second pivot member 62b contacts with the pair of first locking surfaces 634 from the upper side. The pair of second locking surfaces 635 are flat surfaces linearly extending from lower end portions of the pair of D-cut surfaces 633 in the X direction and perpendicular to the height direction. As described above, the arch portion 621 of the first pivot member 62a contacts with the pair of second locking surfaces 635 from the upper side. The arch portion 621 of the second pivot member 62b contacts with the pair of first locking surfaces 634 from the upper side and the arch portion 621 of the first pivot member 62a contacts with the pair of second locking surfaces 635 from the upper side as described above, and thereby it is possible to restrict the upward displacement of the operation shaft 63.

[0057] The flange portion 636 is an annular portion linearly extending toward the outer side at a position on the outer peripheral surface of the spring connection portion 632 located on the lower side of the pair of second locking surfaces 635. A portion of the spring connection portion 632 located on the lower side of the flange portion 636 serves as an attachment portion for attaching the holding mechanism 66 thereon. As shown in Figs. 4 and 5, the press-fitting hole 637 is a circular recess formed on the lower surface of the spring connection portion 632 so as to extend toward the upper side. Referring back to Fig. 12, the pressing portion 638 has a function of pressing the pressed surface 453 of the pressing member 45 of the push switch 4. The pressing portion 638 is formed from hard non-magnetic material. The pressing portion 638 includes a shaft portion 6381 press-fitted into the press-fitting hole 637 and a bottom portion 6382 formed on a lower end portion of the shaft portion 6381 so as to extend toward the outer side.

[0058] The shaft portion 6381 has a diameter slightly larger than a diameter of the press-fitting hole 637. Thus, the shaft portion 6381 is press-fitted into the press-fitting hole 637. By press-fitting the shaft portion 6381 into the press-fitting hole 637, the pressing portion 638 is attached to the lower surface of the spring connection portion 632. The bottom portion 6382 is a disk-like portion formed on the lower end portion of the shaft portion 6381 so as to extend toward the outer side. An upper surface of the bottom portion 6382 is a flat surface perpendicular to the height direction. On the other hand, a lower surface of the bottom portion 6382 (that is, a lower surface of the operation shaft 63) is a curved surface protruding toward the lower side. More specifically, the lower surface of the bottom portion 6382 has a spherical shape whose downward protruding amount gradually decreases from its center toward the outer side. Thus, the lower surface of the bottom portion 6382 makes a point contact with the pressed surface 453 of the pressing member 45. Further, since the lower surface of the bottom portion 6382 has the spherical shape, the lower surface of the bottom portion 6382 does not slide on the pressed surface 453 of the pressing member 45 when the operation shaft 63 performs the tilting movement, and thereby the point contact between the lower surface of the bottom portion 6382 and the pressed surface 453 is maintained. Further, even when the operation shaft 63 performs the tilting movement, the point contact between the lower surface of the bottom portion 6382 and the pressed surface 453 of the pressing member 45 is maintained. Thus, even in a state that the operation shaft 63 is tilted, the operation shaft 63 is displaced toward the lower side according to the pressing operation applied to the operation shaft 63 from the user to press the push switch 4.

[0059] Further, a rotational center of the tilting movement of the operation shaft 63 is located between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b. Further, in the multi-directional input device 1 of the present invention, the bottom surface of the bottom portion 6382 is formed so that a center (a center of curvature) of a circle of curvature (a contact circle) of the spherical shape of the lower surface of the bottom portion 6382 is located so as to substantially coincide with the rotational center of the tilting movement of the operation shaft 63. Thus, even if the operation shaft 63 is tilted from the upright neutral state, a height-direction position of the point contact between the lower surface of the bottom portion 6382 and the pressed surface 453 of the pressing member 45 does not change. Therefore, a downward displacement amount of the operation shaft 63 required for turning on the push switch 4 when the operation shaft 63 is in the upright neutral state is substantially equal to a downward displacement amount of the operation shaft 63 required for turning on the push switch 4 when the operation shaft 63 is tilted.

[0060] Referring back to Fig. 10, the housing cover 65 is a member attached to the upper housing 61 from the upper side. Similar to the upper housing 61, the housing cover 65 is formed from hard non-magnetic material. The housing cover 65 includes an upper plate 651, a circular opening 652 formed in the upper plate 651, four wall portions 653 extending from the upper plate 651 toward the lower side with being spaced apart from each other, and four cutout portions 654 separating the four wall portions 653 from each other.

[0061] The upper plate 651 is a plate-like portion having an upper surface and a lower surface perpendicular to the height direction. The upper plate 651 has a planar shape corresponding to an upper surface of the upper housing 61. The upper plate 651 is located on the upper side of the upper housing 61, and thus the upper leaf spring assembly 8a (see Fig. 12) of the holding mechanism 66, which will be described later, is sandwiched between a lower surface of the upper plate 651 and the upper surface of the upper housing 61. The opening 652 is formed in a center of the upper plate 651 so as to pass through the upper plate 651 in the height direction. The four wall portions 653 are curved portions linearly extending from an edge portion of the lower surface of the upper plate 651 at regular angular intervals of 90 degrees toward the lower side with being spaced apart from each other. The four cutout portions 654 are provided between the wall portions 653 to separate the four wall portions 653 from each other. The four wall portions 653 support the outer peripheral surface of the body portion 611 of the upper housing 61 from the outer side. Further, the four shaft holes 613 of the upper housing 61 are exposed to the outside through the four cutout portions 654. When the housing cover 65 is attached to the upper housing 61, the pair of protruding surfaces 612 of the upper housing 61 are respectively contained in the two cutout portions 654 which face each other in the X direction. The protruding surfaces 612 respectively engage with the cutout portions 654 to prevent rotation of the housing cover 65 on the upper housing 61.

[0062] The holding mechanism 66 has a function of elastically holding the operation shaft 63 in the upright neutral state. As shown in Fig. 12, the holding mechanism 66 includes the upper leaf spring assembly 8a, the lower leaf spring assembly 8b held so as to be spaced apart from the upper leaf spring assembly 8a in the height direction, a cylindrical bush 67 located between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b, an upper rivet 68a for supporting the upper leaf spring assembly 8a from the upper side, and a lower rivet 68b for supporting the lower leaf spring assembly 8b from the lower side.

[0063] As shown in Fig. 13, the upper leaf spring assembly 8a includes a plurality of upper leaf springs 9a (in the illustrated aspect, two upper leaf springs 9a) held so as to be spaced apart from each other in the height direction, an inner spacer 81, and an outer spacer 82. The inner spacer 81 and the outer spacer 82 connect between the plurality of upper leaf springs 9a. The plurality of upper leaf springs 9a are formed from non-magnetic spring material such as stainless steel. The plurality of upper leaf springs 9a are held by the inner spacer 81 and the outer spacer 82 so as to be spaced apart from each other in the height direction and face each other in the height direction in parallel.

[0064] As shown in Fig. 14, each of the upper leaf springs 9a includes an annular outer frame 91 fixedly held on the upper surface or a lower surface of the upper housing 61, an inner frame 92 located on the inner side of the outer frame 91 and having a through-hole 93, a plurality of spring portions 94 (in the illustrated aspect, three spring portions 94) connecting between the outer frame 91 and the inner frame 92, and a plurality of locking portions 95 (in the illustrated aspect, three locking portions 95) formed on an inner peripheral surface of the outer frame 91.

[0065] The outer frame 91 is an annular portion having an upper surface and a lower surface perpendicular to the height direction. The outer frame 91 is fixed to the upper housing 61. The inner frame 92 is a disk-like portion located on the inner side of the outer frame 91 so as to be concentric with the outer frame 91. The inner frame 92 has the circular through-hole 93 formed concentrically with the inner frame 92. As shown in Fig.17, the lower portion of the spring connection portion 632 of the operation shaft 63 located on the lower side of the flange portion 636 passes through the through-hole 93. Referring back to Fig. 14, the plurality of spring portions 94 connect between the outer frame 91 and the inner frame 92 so that the inner frame 92 can be displaced with respect to the outer frame 91. In this regard, the term of "displacement" or "displace" means a height-direction displacement of the inner frame 92 with respect to the outer frame 91 and a lateral-direction (X direction or Y direction) displacement of the inner frame 92 with respect to the outer frame 91 as well as a tortional-direction displacement of the inner frame 92 that the inner frame 92 is tilted around the X direction or the Y direction and the inner frame 92 is tilted with respect to the outer frame 91.

[0066] Each of the spring portions 94 includes a first connecting portion 941 connected to the inner peripheral surface of the outer frame 91, a second connecting portion 942 connected to an outer peripheral surface of the inner frame 92, and an arm portion 943 connecting between the first connecting portion 941 and the second connecting portion 942. The first connecting portion 941 is a plate-like portion extending in a radial direction of the outer frame 91 and the inner frame 92. One end portion of the first connecting portion 941 is connected to the inner peripheral surface of the outer frame 91. Another end portion of the first connecting portion 941 is connected to an outer surface of one end portion of the arm portion 943. The second connecting portion 942 is a plate-like portion extending in the radial direction of the outer frame 91 and the inner frame 92. One end portion of the second connecting portion 942 is connected to the outer peripheral surface of the inner frame 92. Another end portion of the second connecting portion 942 is connected to an outer surface of another end portion of the arm portion 943.

[0067] The arm portion 943 is a portion extending in an arcuate shape so as to connect between the first connecting portion 941 and the second connecting portion 942. The arm portion 943 extends from the first connecting portion 941 toward the second connecting portion 942 in one of a clockwise direction and a counterclockwise direction. In the illustrated aspect in Fig. 14, each of the arm portions 943 of each upper leaf spring 9a extends in the clockwise direction in the arcuate shape from the first connecting portion 941 toward the second connecting portion 942. The plurality of arm portions 943 extend in the arcuate shape so as not to be in contact with each other in a space between the outer frame 91 and the inner frame 92.

[0068] The arm portion 943 includes a first narrow portion 9431a connected to the first connecting portion 941, a second narrow portion 9431b connected to the second connecting portion 942, and a wide portion 9432 connecting between the first narrow portion 9431a and the second narrow portion 9431b. The first narrow portion 9431a, the second narrow portion 9431b, and the wide portion 9432 are continuously formed and extend with the same radius of curvature. The first narrow portion 9431a and the second narrow portion 9431b have the same width (a length in the radial direction of the outer frame 91 and the inner frame 92) as each other. The wide portion 9432 has a width wider than widths of the first narrow portion 9431a and the second narrow portion 9431b. One end portion of the first narrow portion 9431a is connected to the first connecting portion 941 and another end portion of the first narrow portion 9431a is connected to the wide portion 9432. One end portion of the second narrow portion 9431b is connected to the second connecting portion 942 and another end portion of the second narrow portion 9431b is connected to the wide portion 9432. When the inner frame 92 is displaced with respect to the outer frame 91, the plurality of spring portions 94 are elastically deformed, and thereby spring force for returning the inner frame 92 to a steady position is generated. Although the number of the spring portions 94 of the upper leaf spring 9a is three in the illustrated aspect, the present invention is not limited thereto. The scope of the present invention also involves an aspect in which the upper leaf spring 9a has four or more spring portions 94.

[0069] Each of the locking portions 95 is formed on the inner peripheral surface of the outer frame 91 so as to extend from a portion adjacent to the first connecting portion 941 from an opposite side of the arm portion 943 in the radial direction of the outer frame 91 and the inner frame 92. When the upper leaf spring assembly 8a is placed on the upper surface of the upper housing 61, the locking portions 95 respectively engage with the upper end portions of the locking pieces 614 protruding from the body portion 611 of the upper housing 61 toward the upper side to provide positioning and anti-rotation of the upper leaf spring assembly 8a on the upper surface of the upper housing 61.

[0070] The plurality of upper leaf spring 9a held so as to be spaced apart from each other in the height direction and face each other in parallel are arranged so that the first connecting portions 941, the second connecting portions 942, the plurality of arm portions 943, and the locking portions 95 of the spring portions 94 of the upper leaf springs 9a overlap each other in the vertical direction. With this configuration, when the operation shaft 63 is tilted, the arm portions 943 of the plurality of upper leaf springs 9a located on the upper side and the lower side are subjected to the same stresses at the same position and the same torsional motion is generated, so that it is possible to prevent the arm portions 943 located on the upper side and the lower side from interfering with each other.

[0071] Referring back to Fig. 13, the inner spacer 81 and the outer spacer 82 are members for connecting between the plurality of upper leaf springs 9a in order to integrate the plurality of upper leaf springs 9a with each other. The inner spacer 81 is an annular member having an inner diameter and an outer diameter which are respectively equal to an inner diameter and an outer diameter of the inner frame 92 of each upper leaf spring 9a. The inner spacer 81 has a flat upper surface and a flat lower surface perpendicular to the height direction. The upper surface of the inner spacer 81 is fixed on a lower surface of the inner frame 92 of the upper leaf spring 9a located on the upper side, and the lower surface of the inner spacer 81 is fixed on an upper surface of the inner frame 92 of the upper leaf spring 9a located on the lower side by arbitrary fixing means such as an adhesive. The outer spacer 82 is an annular member having an inner diameter and an outer diameter which are respectively equal to an inner diameter and an outer diameter of the outer frame 91 of each upper leaf spring 9a. The outer spacer 82 has a flat upper surface and a flat lower surface perpendicular to the height direction. The upper surface of the outer spacer 82 is fixed on a lower surface of the outer frame 91 of the upper leaf spring 9a located on the upper side and the lower surface of the outer spacer 82 is fixed on an upper surface of the outer frame 91 of the upper leaf spring 9a located on the lower side by arbitrary fixing means such as an adhesive. With this configuration, the plurality of upper leaf springs 9a are integrated with each other, and thus the plurality of upper leaf springs 9a serve as one leaf spring.

[0072] Referring back to Fig. 12, the lower leaf spring assembly 8b is provided so as to be located on the lower side of the upper leaf spring assembly 8a and spaced apart from the upper leaf spring assembly 8a in the height direction. As shown in Fig. 15, the lower leaf spring assembly 8b includes a plurality of lower leaf springs 9b (in the illustrated aspect, two lower leaf springs 9b) held so as to be spaced apart from each other in the height direction, an inner spacer 81, and an outer spacer 82. The inner spacer 81 and the outer spacer 82 connect between the plurality of lower leaf springs 9b. Since the inner spacer 81 and the outer spacer 82 of the lower leaf spring assembly 8b have the same configurations as the inner spacer 81 and the outer spacer 82 of the upper leaf spring assembly 8a described above, description for the inner spacer 81 and the outer spacer 82 of the lower leaf spring assembly 8b will be omitted.

[0073] As shown in Fig. 16, the lower leaf spring 9b has the same configuration as the configuration of the upper leaf spring 9a except that the extending direction of each arm portion 943 of the spring portions 94 is changed. Thus, differences between the upper leaf spring 9a and the lower leaf spring 9b will be described in detail, and description for the same points of the lower leaf spring 9b as the upper leaf spring 9a will be omitted.

[0074] Each of the arm portions 943 of the spring portions 94 of the lower leaf spring 9b extends from the first connecting portion 941 toward the second connecting portion 942 in another one of the clockwise direction and the counterclockwise direction. In the illustrated aspect in Fig. 16, each of the arm portions 943 of the spring portions 94 of the lower leaf spring 9b extends from the first connecting portion 941 toward the second connecting portion 942 in the counterclockwise direction in the arcuate shape. Namely, an extending direction of each arm portion 943 of the upper leaf spring 9a is opposite to an extending direction of each arm portion 943 of the lower leaf spring 9b. Thus, the upper leaf spring 9a and the lower leaf spring 9b are configured to be vertically symmetrical to each other (configured so that its front and back are symmetrical). In other words, the lower leaf spring 9b corresponds to the upper leaf spring 9a provided on the lower side of the upper housing 61 in a state that the upper leaf spring 9a is upside down.

[0075] As shown in Figs. 4 and 5, the upper leaf spring assembly 8a is sandwiched between the upper surface of the upper housing 61 and the lower surface of the upper plate 651 of the housing cover 65. With this configuration, the plurality of upper leaf springs 9a of the upper leaf spring assembly 8a can be fixedly held by the upper housing 61. On the other hand, the lower leaf spring assembly 8b is held between the lower surface of the upper housing 61 and the upper surface of the body portion 51 of the lower housing 5. With this configuration, the plurality of lower leaf springs 9b of the lower leaf spring assembly 8b can be fixedly held by the upper housing 61.

[0076] Further, the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are provided so that the first connecting portions 941 of the upper leaf springs 9a overlap with the first connecting portions 941 of the lower leaf springs 9b and the second connecting portions 942 of the upper leaf springs 9a overlap with the second connecting portions 942 of the lower leaf springs 9b in the planar view from the height direction. Thus, the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are attached to the operation shaft 63 in a state that the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are completely vertically symmetrical to each other (so that their fronts and backs are completely symmetrical to each other).

[0077] Although the outer frame 91 of each of the upper leaf springs 9a and the lower leaf springs 9b has the annular shape in the illustrated aspect, the present invention is not limited thereto. The shape of the outer frame 91 can be appropriately changed according to the shapes of the body portion 51 of the lower housing 5 and the body portion 611 of the upper housing 61. For example, the scope of the present invention also involves an aspect in which the outer frame 91 of each of the upper leaf springs 9a and the lower leaf springs 9b has an elliptical annular shape or a polygonal annular shape. Further, the number of the spring portions 94 of each of the upper leaf springs 9a and the lower leaf springs 9b is not particularly limited as long as the number of the spring portions 94 of each of the upper leaf springs 9a and the lower leaf springs 9b is three or more and the inner frame 92 is connected to the outer frame 91 by the spring portions 94 so that the inner frame 92 can be displaced with respect to the outer frame 91. The scope of the present invention also involves an aspect in which each of the upper leaf springs 9a and the lower leaf springs 9b includes four, five, or more spring portions 94.

[0078] As is clear from Figs. 14 and 16, each of the upper leaf springs 9a and the lower leaf springs 9b has a rotationally asymmetric shape in the planar view from the height direction. Thus, a stiffness of each of the upper leaf springs 9a and the lower leaf springs 9b becomes anisotropic. For example, a lateral stiffness of the upper leaf spring 9a when the inner frame 92 is displaced in the +X direction differs from a lateral stiffness of the upper leaf spring 9a when the inner frame 92 is displaced in the -X direction. In the multi-directional input device 1 of the present invention, the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are attached to the operation shaft 63 so that the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are completely vertically symmetrical to each other (so that their fronts and backs are symmetrical to each other). Thus, the anisotropy of the stiffness of each upper leaf spring 9a and the anisotropy of the stiffness of each lower leaf spring 9b cancel out each other. As a result, a stiffness of the holding mechanism 66 obtained by combining the stiffnesses of the upper leaf springs 9a and the stiffnesses of the lower leaf springs 9b does not have anisotropy. Thus, reaction force against the tilting operation to the operation shaft 63 which is elastically held by the holding mechanism 66 does not have anisotropy, and thereby the multi-directional input device 1 can be preferably used as the joystick for the controller of the game machine.

[0079] Further, when a straight line is drawn toward the outer side from a center of the inner frame 92 to an arbitrary point on the inner peripheral surface of the outer frame 91 along the radial direction of the inner frame 92 in the planar view from the height direction of each of the upper leaf springs 9a and the lower leaf springs 9b, at least one of the arm portions 943 and two spaces which are respectively located on the outer side and the inner side of the at least one of the arm portions 943 and in which the components (such as the arm portions 943) of the upper leaf spring 9a or the lower leaf spring 9b do not exist are always located on the straight line. The two spaces respectively located on the outer side and the inner side of the at least one of the arm portions 943 allow the at least one of the arm portions 943 to elastically buckle (elastically bend) in the height direction. Thus, it is possible to configure each of the upper leaf springs 9a and the lower leaf springs 9b so that a torsional stiffness with respect to the torsional-direction displacement that the inner frame 92 is tilted with respect to the outer frame 91 is significantly different from a lateral stiffness with respect to the lateral-direction displacement of the inner frame 92 with respect to the outer frame 91. More specifically, each of the upper leaf springs 9a and the lower leaf springs 9b is configured so that the torsional stiffness is significantly less than the lateral stiffness.

[0080] Further, a longitudinal stiffness of each of the upper leaf springs 9a and the lower leaf springs 9b with respect to the height-direction displacement of the inner frame 92 to the outer frame 91 is determined by a shape (a length and a width) of each of the arm portions 943. Due to the shape of each of the upper leaf springs 9a and the lower leaf springs 9b respectively shown in Figs. 14 and 16, the longitudinal stiffness of each of the upper leaf springs 9a and the lower leaf springs 9b is significantly less than the torsional stiffness and the lateral stiffness. Thus, each of the upper leaf springs 9a and the lower leaf springs 9b is configured so that the longitudinal stiffness is significantly less than the torsional stiffness and the lateral stiffness.

[0081] Further, the operation shaft assembly 6 of the present embodiment is provided on the upper surface of the body portion 51 of the lower housing 5 so that the outer frame 91 of each of the upper leaf springs 9a and the lower leaf springs 9b is located on the lower side of the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b when the operation shaft 63 is in the neutral state. With this configuration, a downward pretension is applied to the operation shaft 63 when the operation shaft 63 is in the neutral state. Since the downward pretension is applied to the operation shaft 63 when the operation shaft 63 is in the neutral state as described above, it is possible to prevent backlash of the operation shaft 63. Thus, it is possible to reduce friction between the lower surface of the bottom portion 6382 and the pressed surface 453 when the operation shaft 63 performs the tilting movement. As a result, it is possible to prevent the friction between the lower surface of the bottom portion 6382 and the pressed surface 453 from affecting the tilting operation to the operation shaft 63. Further, it is possible to prevent the operation shaft 63 and the pressing member 45 from wearing away, and thereby it is possible to increase a product life of the multi-directional input device 1.

[0082] Further, as shown in Figs. 4 and 5, the lower surface of the bottom portion 6382 contacts with the pressed surface 453 of the pressing member 45 in the state that the operation shaft 63 is held in the neutral state. Since the multi-directional input device 1 is configured so that the downward pretension is applied to the operation shaft 63 as described above, a steady position of the operation shaft 63 in the height direction is determined by a balance between the downward pretension with respect to the operation shaft 63 and a sum of upward repulsive force from the pressing member 45 and upward elastic restoring force of the holding mechanism 66 with respect to the operation shaft 63.

[0083] Further, when the operation shaft 63 is in the neutral position, the outer frames 91 of the upper leaf springs 9a face the outer frames 91 of the lower leaf springs 9b in parallel and the inner frames 92 of the upper leaf springs 9a face the inner frames 92 of the lower leaf springs 9b in parallel. Thus, the upper leaf springs 9a and the lower leaf springs 9b face each other in parallel.

[0084] Referring back to Fig. 12, the bush 67 is a cylindrical member formed from hard non-magnetic material. The bush 67 has an inner diameter and an outer diameter which are substantially equal to the inner diameter and the outer diameter of the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b, respectively. The bush 67 is located between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b. An upper surface of the bush 67 contacts with the lower surface of the inner frame 92 of the lower one of the upper leaf springs 9a of the upper leaf spring assembly 8a. A lower surface of the bush 67 contacts with the upper surface of the inner frame 92 of the upper one of the upper lower leaf springs 9b of the lower leaf spring assembly 8b. Thus, the upper leaf spring assembly 8a and the lower leaf spring assembly 8b are connected to the operation shaft 63 with being spaced apart from each other in the height direction by a height of the bush 67.

[0085] The upper rivet 68a and the lower rivet 68b have the same configuration except that attachment postures with respect to the operation shaft 63 are different from each other. Thus, a configuration of the upper rivet 68a will be described in detail as a representative. The upper rivet 68a is a member formed from hard non-magnetic material. The upper rivet 68a includes a cylindrical portion 681 extending in the height direction and a flange portion 682 linearly extending from an upper end portion of the cylindrical portion 681 (in the case of the lower rivet 68b, a lower end portion of the cylindrical portion 681) toward the outer side. The cylindrical portion 681 has an inner diameter substantially equal to the diameter of the spring connection portion 632 of the operation shaft 63 and an outer diameter substantially equal to the inner diameter of the bush 67. The flange portion 682 has an outer diameter substantially equal to the outer diameter of the flange portion 636 of the operation shaft 63.

[0086] Fig. 17 is a cross-sectional perspective view for explaining a state that the operation shaft 63 is held by the holding mechanism 66 having the above-described configuration. For simplifying the drawing, only the operation shaft 63 and the holding mechanism 66 are shown in Fig. 17. As shown in Fig. 17, the portion of the spring connection portion 632 of the operation shaft 63 located on the lower side of the flange portion 636 passes through the cylindrical portions 681 of the upper rivet 68a and the lower rivet 68b. The flange portion 682 of the upper rivet 68a is supported from the upper side by the flange portion 636. The flange portion 682 of the lower rivet 68b is supported from the lower side by the bottom portion 6382 of the pressing portion 638 press-fitted into the press-fitting hole 637 of the operation shaft 63. Further, the cylindrical portions 681 of the upper rivet 68a and the lower rivet 68b are inserted into the through-holes 93 of the upper leaf springs 9a or the lower leaf springs 9b and an opening of the bush 67. The inner frames 92 of the upper leaf springs 9a are sandwiched between the lower surface of the flange portion 682 of the upper rivet 68a and the upper surface of the bush 67. The inner frames 92 of the lower leaf springs 9b are sandwiched between the upper surface of the flange portion 682 of the lower rivet 68b and the lower surface of the bush 67.

[0087] As described above, the spring connection portion 632 of the operation shaft 63 is connected to the inner frames 92 of the upper leaf springs 9a and the lower leaf springs 9b through the upper rivet 68a and the lower rivet 68b in the state that the spring connection portion 632 is passed through the through-holes 93 of the upper leaf springs 9a and the lower leaf springs 9b. With this configuration, the operation shaft 63 can be elastically held by the upper leaf springs 9a and the lower leaf springs 9b.

[0088] The outer frames 91 of the upper leaf springs 9a and the lower leaf springs 9b are fixed to the upper housing 61 as described above, and the inner frames 92 and the spring portions 94 of the upper leaf springs 9a and the lower leaf springs 9b are suspended by the upper housing 61. With this configuration, the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b can perform the height-direction displacement with respect to the outer frame 91, the lateral-direction (the X direction or the Y direction) displacement with respect to the outer frame 91, and the torsional-direction displacement that the inner frame 92 is tilted around the X direction or the Y direction and tilted with respect to the outer frame 91. Thus, the holding mechanism 66 has a longitudinal stiffness with respect to the height-direction displacement of the operation shaft 63, a lateral stiffness with respect to the lateral-direction displacement of the operation shaft 63, and a torsional stiffness with respect to the torsional-direction displacement of the operation shaft 63. In the multi-directional input device 1 of the present invention, the holding mechanism 66 is configured so that the lateral stiffness and the torsional stiffness which are associated with the tilting movement of the operation shaft 63 are significantly different from each other. More specifically, the holding mechanism 66 is configured so that the lateral stiffness is larger than the torsional stiffness.

[0089] The lateral stiffness of the holding mechanism 66 increases as either one of the width of the arm portion 943 of each spring portion 94 of each upper leaf spring 9a and each lower leaf spring 9b and a height-direction separation distance between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b (i.e., the height of the bush 67) increases. On the other hand, the torsional stiffness of the holding mechanism 66 increases as a thickness of each upper leaf spring 9a and each lower leaf spring 9b increases. Thus, by adjusting the width of each arm portion 943 of each upper leaf spring 9a and each lower leaf spring 9b, the height-direction separation distance between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b, and the thicknesses of each upper leaf spring 9a and each lower leaf spring 9b, it is possible to adjust a balance between the lateral stiffness and the torsional stiffness of the holding mechanism 66.

[0090] Further, the above-mentioned wide portions 9432 of the arm portions 943 of the upper leaf springs 9a and the lower leaf springs 9b are formed to adjust the lateral stiffness of the holding mechanism 66. Thus, the balance between the lateral stiffness and the torsional stiffness can be also adjusted by changing a shape of each wide portion 9432. Further, by adjusting the numbers of the upper leaf springs 9a and the lower leaf springs 9b, it is also possible to adjust the balance between the lateral stiffness and torsional stiffness of the holding mechanism 66. As the numbers of the upper leaf springs 9a and the lower leaf springs 9b increase, the lateral stiffness of the holding mechanism 66 becomes much larger relative to the torsional stiffness. Thus, the number of the upper leaf springs 9a of the upper leaf spring assembly 8a and the number of the lower leaf springs 9b of the lower leaf spring assembly 8b can be appropriately changed as needed. For example, the scope of the present invention also involves an aspect in which the number of the upper leaf springs 9a of the upper leaf spring assembly 8a is one and the number of the lower leaf springs 9b of the lower leaf spring assembly 8b is one. In this case, the inner spacers 81 and the outer spacers 82 of the upper leaf spring assembly 8a and the lower leaf spring assembly 8b can be omitted.

[0091] Further, the scope of the present invention also involves another aspect in which the number of the upper leaf springs 9a of the upper leaf spring assembly 8a is three and the number of the lower leaf springs 9b of the lower leaf spring assembly 8b is three. In this case, the upper leaf spring 9a located between the upper leaf spring 9a located at the uppermost position and the upper leaf spring 9a at the lowermost position serves as a balancer for correcting non-uniformity between the stiffness (the longitudinal stiffness, the lateral stiffness, and the torsional stiffness) of the upper leaf spring 9a located at the uppermost position and the stiffness of the upper leaf spring 9a located at the lowermost position to balance between the upper leaf spring 9a located at the uppermost position and the upper leaf spring 9a located at the lowermost position. Similarly, the lower leaf spring 9b located between the lower leaf spring 9b located at the uppermost position and the lower leaf spring 9b located at the lowermost position serves as a balancer for correcting non-uniformity between the stiffness of the lower leaf spring 9b located at the uppermost position and the stiffness of the lower leaf spring 9b located at the lowermost position to balance between the lower leaf spring 9b located at the uppermost position and the lower leaf spring 9b located at the lowermost position.

[0092] When the operation shaft 63 performs the tilting movement according to the tilting operation applied from the user, the lateral-direction displacement and the torsional-direction displacement of the operation shaft 63 occur. Thus, reaction force against the tilting movement of the operation shaft 63 is a sum of reaction force against the lateral-direction displacement of the operation shaft 63 and reaction force against the torsional-direction displacement of the operation shaft 63. Fig. 18 shows a dynamic model for the lateral-direction displacement of the operation shaft 63 and a dynamic model for the torsional-direction displacement of the operation shaft 63. A motion equation of the lateral-direction displacement and a motion equation of the torsional-direction displacement shown in Fig. 18 can be expressed by the following equation (1). In the following equation (1), "F" is force [N] applied to the operation shaft 63, "m" is a weight [g] of the operation shaft 63, "x" is a displacement amount [m] of the operation shaft 63, "t" is time [s], and "k sp " is a lateral-direction or torsional-direction spring constant [N / m] of the holding mechanism 66. [Equation 1] F t = m d 2 x t d t 2 = − k sp x t m: weight k sp : spring constant

[0093] Since the holding mechanism 66 is configured so that the lateral stiffness is larger than the torsional stiffness as described above, a lateral spring constant "k" in Fig. 18 is larger than a torsional spring constant "k T ". Since the lateral spring constant "k" is large, an increase amount of the reaction force according to an increase of the tilt angle of the operation shaft 63 when the operation shaft 63 performs the tilting movement becomes large in a phase in which the lateral-direction displacement of the operation shaft 63 is dominant. On the other hand, since the torsional spring constant "k T " is smaller than the lateral spring constant "k", the increase amount of the reaction force according to the increase of the tilt angle of the operation shaft 63 becomes small in a phase in which the torsional-direction displacement of the operation shaft 63 is dominant.

[0094] Each of Figs. 19 and 20 is a diagram showing a stress distribution of each of the spring portions 94 of the upper leaf springs 9a and the lower leaf springs 9b when the user applies the tilting operation to the operation shaft 63. Fig. 19 shows the stress distribution of each of the spring portions 94 of the upper leaf springs 9a and the lower leaf springs 9b in an initial state of the tilting movement in which the tilt angle of the operation shaft 63 is small. Fig. 20 shows the stress distribution of each of the spring portions 94 of the upper leaf springs 9a and the lower leaf springs 9b in a second state of the tilting movement in which the tilt angle of the operation shaft 63 is larger than a predetermined value. In each of Figs. 19 and 20, the stress is indicated with a gray scale bar normalized so that a maximum value of the stress generated in the upper leaf springs 9a and the lower leaf springs 9b is set to 1.

[0095] In the initial state shown in Fig. 19 in which the tilt angle of the operation shaft 63 is small, the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b is displaced in the lateral direction. On the other hand, the torsional-direction displacement of the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b does not substantially occur. Thus, as shown in Fig. 19, strong compressive stress is generated in an inner side portion of each of the spring portions 94 and strong tensile stress is generated in an outer side portion of each of the spring portions 94 in the initial state. As a result, the operation shaft 63 is mainly displaced in the lateral direction in the initial state. Thus, the increase amount of the reaction force according to the increase of the tilt angle of the operation shaft 63 becomes large in the initial state.

[0096] After that, when the tilt angle of the operation shaft 63 increases, the upper leaf springs 9a and the lower leaf springs 9b are shifted from the initial state to the second state shown in Fig. 20. In the second state, each of the spring portions 94 of the upper leaf springs 9a and the lower leaf springs 9b is elastically buckled (elastically bent). Thus, in the second state, a further lateral-direction displacement of the inner frame 92 of each of the upper leaf springs 9a and the lower leaf springs 9b does not substantially occur. On the other hand, elastic buckling of each of the spring portions 94 causes the torsional-direction displacement of the inner frame 92. Thus, as shown in Fig. 20, buckling (bending) stress is generated in each of the spring portions 94 in the second state. On the other hand, the compressive stress and the tensile stress generated in the initial state do not substantially occur in each of the spring portions 94. Thus, the operation shaft 63 is mainly displaced in the torsional direction in the second state. As a result, the increase amount of the reaction force according to the increase of the tilt angle of the operation shaft 63 becomes relatively small in the second state.

[0097] Fig. 21 is a graph showing reaction force characteristics against the tilting operation to the operation shaft 63. In the graph of Fig. 21, a horizontal axis represents the tilt angle of the operation shaft 63 and a vertical axis represents the reaction force against the tilting operation to the operation shaft 63. As shown in Fig. 21, the reaction force rapidly increases according to the increase of the tilt angle of the operation shaft 63 in the initial state. After that, when the tilt angle of the operation shaft 63 exceeds the predetermined value and the upper leaf springs 9a and the lower leaf springs 9b are shifted from the initial state to the second state, the increase of the reaction force according to the increase of the tilt angle of the operation shaft 63 becomes suddenly gradual. As mentioned in the section of "BACKGROUND ART", such non-linear reaction force characteristics are particularly useful when the multi-directional input device 1 is used in the handheld controller of the game machine.

[0098] Referring back to Fig. 6, the detection mechanism 7 has a function of detecting each of the pivot angles of the first pivot member 62a and the second pivot member 62b. The detection mechanism 7 includes the two magnetic sensors 71 provided on the circuit board 3 and the two magnet assemblies 72 respectively provided on the first pivot member 62a and the second pivot member 62b so as to respectively face the two magnetic sensors 71 when the operation shaft 63 is held in the neutral state.

[0099] As shown in Figs. 4 and 5, each of the two magnet assemblies 72 has a magnet 721 facing the corresponding magnetic sensor 71 when the operation shaft 63 is held in the neutral state. One of the magnet assemblies 72 is attached to the bearing portion 626 of the first pivot member 62a. Similarly, another one of the magnet assemblies 72 is attached to the bearing portion 626 of the second pivot member 62b. When the first pivot member 62a is pivotally moved, a positional relationship between the magnet 721 of the magnet assembly 72 attached to the first pivot member 62a and the corresponding magnetic sensor 71 changes. Thus, the corresponding magnetic sensor 71 can detect the pivot angle of the first pivot member 62a. Similarly, when the second pivot member 62b is pivotally moved, a positional relationship between the magnet 721 of the magnet assembly 72 attached to the second pivot member 62b and the corresponding magnetic sensor 71 changes. Thus, the corresponding magnetic sensor 71 can detect the pivot angle of the second pivot member 62b.

[0100] As described above, in the multi-directional input device 1 of the present invention, the holding mechanism 66 for elastically holding the operation shaft 63 in the neutral state is configured by using the upper leaf springs 9a and the lower leaf springs 9b, and thereby it is possible to provide the non-linear reaction force characteristics which are useful when the multi-directional input device 1 is used in the handheld controller of the game machine. Further, the inner frame 92 and the spring portions 94 of each of the upper leaf springs 9a and the lower leaf springs 9b are suspended by the upper housing 61 as described above. Thus, when the operation shaft 63 performs the tilting movement, the inner frame 92 and the spring portions 94 do not slide on the other members in the upper housing 61. Therefore, even if the tilting operation with respect to the operation shaft 63 is repeatedly applied, the upper leaf springs 9a and the lower leaf springs 9b do not wear away, and thereby it is possible to significantly increase the product life of the multi-directional input device 1. Further, since the inner frame 92 and the spring portions 94 do not slide on the other members during a returning movement of the operation shaft 63, there is no frictional force which disturbs the returning of the operation shaft 63 to the neutral state. Therefore, it is possible to reduce a hysteresis of the multi-directional input device 1.

[0101] Further, in the multi-directional input device 1 of the present invention, the extending direction of the arm portions 943 of each of the upper leaf springs 9a and the extending direction of the arm portions 943 of each of the lower leaf springs 9b are opposite to each other. Thus, the upper leaf springs 9a and the lower leaf springs 9b are configured and arranged so that the upper leaf springs 9a and the lower leaf springs 9b are vertically symmetric to each other (so that the fronts and backs of the upper leaf springs 9a and the lower leaf springs 9b are symmetric to each other). Therefore, the anisotropies of the stiffnesses of the upper leaf springs 9a and the anisotropies of the stiffnesses of the lower leaf springs 9b cancel out each other. As a result, the stiffness of the holding mechanism 66 obtained by combining the stiffnesses of the upper leaf springs 9a and the stiffnesses of the lower leaf springs 9b does not have the anisotropy. Therefore, the reaction force against the tilting operation to the operation shaft 63 elastically held by the holding mechanism 66 does not have the anisotropy, and thereby the multi-directional input device 1 can be preferably used as the joystick used for the controller of the game machine.

[0102] Further, in the multi-directional input device 1 of the present invention, the operation shaft 63 is elastically held by the upper leaf springs 9a and the lower leaf springs 9b so that the operation shaft 63 can be displaced in the height direction. Thus, it is possible to displace the operation shaft 63 toward the lower side according to the pressing operation applied to the operation shaft 63 from the user to press the push switch 4. Therefore, the multi-directional input device 1 can accept not only the tilting operation with respect to the operation shaft 63 from the user but also the pressing operation with respect to the operation shaft 63 from the user. As described above, each of the upper leaf springs 9a and the lower leaf springs 9b is configured so that the longitudinal stiffness is significantly smaller than the torsional stiffness and the lateral stiffness. Therefore, reaction force against the pressing operation with respect to the operation shaft 63 is mainly determined by a stiffness of the movable contact 43 of the push switch 4.

[0103] Further, in the multi-directional input device 1 of the present invention, when the straight line is drawn toward the outer side from the center of the inner frame 92 to the arbitrary point on the inner peripheral surface of the outer frame 91 along the radial direction of the inner frame 92 in the planar view from the height direction of each of the upper leaf springs 9a and the lower leaf springs 9b, the at least one arm portion 943 and the two spaces which are respectively located on the outer side and the inner side of the at least one arm portion 943 and in which the components (such as the arm portions 943 of the upper leaf spring 9a or the lower leaf spring 9b do not exist are always located on the straight line. The two spaces respectively located on the outer side and the inner side of the at least one arm portion 943 allow the at least one arm portion 943 to elastically buckle (elastically bend) in the height direction. Therefore, each of the upper leaf springs 9a and the lower leaf springs 9b can be configured so that the torsional stiffness with respect to the torsional-direction displacement in which the inner frame 92 is tilted with respect to the outer frame 91 is significantly smaller than the lateral stiffness with respect to the lateral-direction displacement of the inner frame 92 with respect to the outer frame 91.

[0104] Further, in the multi-directional input device 1 of the present invention, the inner frames 92 of the upper leaf springs 9a and the inner frames 92 of the lower leaf springs 9b are connected to the spring connection portion 632 of the operation shaft 63 in the state that the inner frames 92 of the upper leaf springs 9a and the inner frames 92 of the lower leaf springs 9b are spaced apart from each other in the height direction. The holding mechanism 66 is configured by using the upper leaf springs 9a and the lower leaf springs 9b which are spaced apart from each other in the height direction and each of which has the torsional stiffness and the lateral stiffness which are significantly different from each other as described above, and thereby the lateral stiffness of the holding mechanism 66 becomes significantly larger than the torsional stiffness of the holding mechanism 66. As a result, it is possible to make the reaction force characteristic with respect to the tilting operation to the operation shaft 63 preferable for being used as the joystick used for the controller of the game machine.

[0105] Further, in the multi-directional input device 1 of the present invention, the upper housing 61 is provided between the outer frame 91 of the upper leaf spring 9a and the outer frame 91 of the lower leaf spring 9b, and the bush 67 is provided between the inner frame 92 of the upper leaf spring 9a and the inner frame 92 of the lower leaf spring 9b. Thus, the outer frame 91 of the upper leaf spring 9a faces the outer frame 91 of the lower leaf spring 9b in parallel, and the inner frame 92 of the upper leaf spring 9a faces the inner frame 92 of the lower leaf spring 9b in parallel. Namely, the upper leaf spring 9a and the lower leaf spring 9b face each other. With this configuration in parallel, a separation distance between the upper leaf spring 9a and the lower leaf spring 9b can be kept constant, and thereby it is possible to stabilize the reaction force characteristic against the tilting operation to the operation shaft 63.

[0106] Further, in the multi-directional input device 1 of the present invention, the rotational center of the tilting movement of the operation shaft 63 is located between the upper leaf spring assembly 8a and the lower leaf spring assembly 8b. Further, the lower surface of the bottom portion 6382 is formed so that the center of the radius of curvature of the spherical shape of the lower surface of the bottom portion 6382 is located at the substantially same height position as the rotation center of the tilting movement of the operation shaft 63. Therefore, even if the operation shaft 63 is tilted from the upright neutral state, the height position of the point contact between the lower surface of the bottom portion 6382 and the pressed surface 453 of the pressing member 45 does not change.

[0107] Although the multi-directional input device of the embodiment of the present invention has been described based on the illustrated embodiment, the present invention is not limited thereto. Each configuration of the embodiment of the present invention can be replaced by any configuration capable of performing the same function or any configuration can be added to each configuration of the embodiment of the present invention.

[0108] A person having ordinary skill in the art and field and art would be able to perform modifications to the described configuration of the multi-directional input device of the embodiment of the present invention without significantly departing from the principle, concept and scope of the present invention and the multi-directional input device having the modified configuration is also involved within the scope of the present invention.

[0109] In addition, the number and types of the components of the multi-directional input device shown in Figs. 3 to 17 are merely illustrative examples and the present invention is not necessarily limited thereto. An aspect in which any component is added or combined or any component is omitted without departing from the principle and intent of the present invention is also involved within the scope of the present invention.INDUSTRIAL APPLICABILITY

[0110] In the multi-directional input device of the present invention, the operation shaft is elastically held in the neutral state by the upper leaf spring and the lower leaf spring fixedly held by the housing so as to face each other with being spaced apart from each other in the height direction. In addition, when the operation shaft performs the tilting movement, the upper leaf spring and the lower leaf spring do not slide on the other members in the housing. Therefore, even if the user repeatedly applies the tilting operation to the multi-directional input device of the present invention, the upper leaf spring and the lower leaf spring do not wear away, and thereby it is possible to greatly increase the product life of the multi-directional input device. Further, the reaction force characteristics with respect to the tilting operation to the operation shaft provided by the upper leaf spring and the lower leaf spring facing each other with being spaced apart from each other in the height direction become the non-linear characteristics which are preferable as the controller of the game machine. Accordingly, the present invention has industrial applicability.

Claims

1. A multi-directional input device, comprising: a housing; a first pivot member having a first slit hole and held by the housing so that the first pivot member can be pivotally moved around a first axis direction; a second pivot member having a second slit hole and held by the housing so that the second pivot member can be pivotally moved around a second axis direction perpendicular to the first axis direction; an operation shaft which is passed through the first slit hole and the second slit hole for pivotally moving the first pivot member and the second pivot member according to a tilting operation applied from a user; a holding mechanism held by the housing and elastically holding the operation shaft in a neutral state; and a detection mechanism for detecting a pivot angle of each of the first pivot member and the second pivot member, wherein the holding mechanism includes at least one upper leaf spring and at least one lower leaf spring which are fixedly held by the housing so as to face each other with being spaced apart from each other in a height direction, wherein each of the at least one upper leaf spring and the at least one lower leaf spring includes: an outer frame fixedly held by the housing, an inner frame located on an inner side of the outer frame and having a through-hole, and a plurality of spring portions for connecting between the outer frame and the inner frame so that the inner frame can be displaced with respect to the outer frame, and wherein the operation shaft is connected to the inner frames of the at least one upper leaf spring and the at least one lower leaf spring in a state that the operation shaft is passed through the through-holes of the inner frames of the at least one upper leaf spring and the at least one lower leaf spring.

2. The multi-directional input device as claimed in claim 1, wherein each of the plurality of spring portions of each of the at least one upper leaf spring and the at least one lower leaf spring includes: a first connecting portion connected to the outer frame, a second connecting portion connected to the inner frame, and an arm portion extending in an arcuate shape so as to connect between the first connecting portion and the second connecting portion.

3. The multi-directional input device as claimed in claim 2, wherein the arm portion of each of the plurality of spring portions of the at least one upper leaf spring extends in the arcuate shape in one of a clockwise direction and a counterclockwise direction from the first connecting portion toward the second connecting portion in a planar view from the height direction, and wherein the arm portion of each of the plurality of spring portions of the at least one lower leaf spring extends in the arcuate shape in another one of the clockwise direction and the counterclockwise direction from the first connecting portion toward the second connecting portion in the planar view from the height direction.

4. The multi-directional input device as claimed in claim 2, wherein the arm portion includes: a first narrow portion connected to the first connecting portion, a second narrow portion connected to the second connecting portion, and a wide portion connecting between the first narrow portion and the second narrow portion and having a width wider than widths of the first narrow portion and the second narrow portion.

5. The multi-directional input device as claimed in claim 2, wherein each of the at least one upper leaf spring and the at least one lower leaf spring further includes a locking portion formed on an inner peripheral surface of the outer frame so as to protrude from a portion adjacent to the first connecting portion in a radial direction of the outer frame.

6. The multi-directional input device as claimed in claim 2, wherein the arm portions of the plurality of spring portions extend in a space between the outer frame and the inner frame so as not to be in contact with each other.

7. The multi-directional input device as claimed in claim 2, wherein the at least one upper leaf spring and the at least one lower leaf spring are provided so that the first connecting portion of the at least one upper leaf spring overlaps with the first connecting portion of the at least one lower leaf spring and the second connecting portion of the at least one upper leaf spring overlaps with the second connecting portion of the at least one lower leaf spring in a planar view from the height direction.

8. The multi-directional input device as claimed in claim 2, wherein the number of the plurality of spring portions of each of the at least one upper leaf spring and the at least one lower leaf spring is three or more.

9. The multi-directional input device as claimed in claim 1, wherein the at least one upper leaf spring and the at least one lower leaf spring are configured so that the at least one upper leaf spring and the at least one lower leaf spring are vertically symmetric to each other.

10. The multi-directional input device as claimed in claim 1, wherein the at least one upper leaf spring contains a plurality of upper leaf springs, wherein the at least one lower leaf spring contains a plurality of lower leaf springs, wherein the holding mechanism includes: the plurality of upper leaf springs spaced apart from each other in the height direction and facing each other, and the plurality of lower leaf springs spaced apart from each other in the height direction and facing each other, wherein the plurality of upper leaf springs face each other in parallel, and wherein the plurality of lower leaf springs face each other in parallel.

11. The multi-directional input device as claimed in claim 10, wherein the holding mechanism further includes: a first spacer located between the plurality of upper leaf springs for holding the plurality of upper leaf springs in a state that the plurality of upper leaf springs are spaced apart from each other in the height direction, and a second spacer located between the plurality of lower leaf springs for holding the plurality of lower leaf springs in a state that the plurality of lower leaf springs are spaced apart from each other in the height direction.

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